Merge tag 's390-6.0-4' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux

[people/ms/linux.git] / fs / cifs / smb2ops.c

// SPDX-License-Identifier: GPL-2.0
/*
 *  SMB2 version specific operations
 *
 *  Copyright (c) 2012, Jeff Layton <jlayton@redhat.com>
 */

#include <linux/pagemap.h>
#include <linux/vfs.h>
#include <linux/falloc.h>
#include <linux/scatterlist.h>
#include <linux/uuid.h>
#include <linux/sort.h>
#include <crypto/aead.h>
#include <linux/fiemap.h>
#include <uapi/linux/magic.h>
#include "cifsfs.h"
#include "cifsglob.h"
#include "smb2pdu.h"
#include "smb2proto.h"
#include "cifsproto.h"
#include "cifs_debug.h"
#include "cifs_unicode.h"
#include "smb2status.h"
#include "smb2glob.h"
#include "cifs_ioctl.h"
#include "smbdirect.h"
#include "fscache.h"
#include "fs_context.h"
#include "cached_dir.h"

/* Change credits for different ops and return the total number of credits */
static int
change_conf(struct TCP_Server_Info *server)
{
        server->credits += server->echo_credits + server->oplock_credits;
        server->oplock_credits = server->echo_credits = 0;
        switch (server->credits) {
        case 0:
                return 0;
        case 1:
                server->echoes = false;
                server->oplocks = false;
                break;
        case 2:
                server->echoes = true;
                server->oplocks = false;
                server->echo_credits = 1;
                break;
        default:
                server->echoes = true;
                if (enable_oplocks) {
                        server->oplocks = true;
                        server->oplock_credits = 1;
                } else
                        server->oplocks = false;

                server->echo_credits = 1;
        }
        server->credits -= server->echo_credits + server->oplock_credits;
        return server->credits + server->echo_credits + server->oplock_credits;
}

static void
smb2_add_credits(struct TCP_Server_Info *server,
                 const struct cifs_credits *credits, const int optype)
{
        int *val, rc = -1;
        int scredits, in_flight;
        unsigned int add = credits->value;
        unsigned int instance = credits->instance;
        bool reconnect_detected = false;
        bool reconnect_with_invalid_credits = false;

        spin_lock(&server->req_lock);
        val = server->ops->get_credits_field(server, optype);

        /* eg found case where write overlapping reconnect messed up credits */
        if (((optype & CIFS_OP_MASK) == CIFS_NEG_OP) && (*val != 0))
                reconnect_with_invalid_credits = true;

        if ((instance == 0) || (instance == server->reconnect_instance))
                *val += add;
        else
                reconnect_detected = true;

        if (*val > 65000) {
                *val = 65000; /* Don't get near 64K credits, avoid srv bugs */
                pr_warn_once("server overflowed SMB3 credits\n");
                trace_smb3_overflow_credits(server->CurrentMid,
                                            server->conn_id, server->hostname, *val,
                                            add, server->in_flight);
        }
        server->in_flight--;
        if (server->in_flight == 0 &&
           ((optype & CIFS_OP_MASK) != CIFS_NEG_OP) &&
           ((optype & CIFS_OP_MASK) != CIFS_SESS_OP))
                rc = change_conf(server);
        /*
         * Sometimes server returns 0 credits on oplock break ack - we need to
         * rebalance credits in this case.
         */
        else if (server->in_flight > 0 && server->oplock_credits == 0 &&
                 server->oplocks) {
                if (server->credits > 1) {
                        server->credits--;
                        server->oplock_credits++;
                }
        }
        scredits = *val;
        in_flight = server->in_flight;
        spin_unlock(&server->req_lock);
        wake_up(&server->request_q);

        if (reconnect_detected) {
                trace_smb3_reconnect_detected(server->CurrentMid,
                        server->conn_id, server->hostname, scredits, add, in_flight);

                cifs_dbg(FYI, "trying to put %d credits from the old server instance %d\n",
                         add, instance);
        }

        if (reconnect_with_invalid_credits) {
                trace_smb3_reconnect_with_invalid_credits(server->CurrentMid,
                        server->conn_id, server->hostname, scredits, add, in_flight);
                cifs_dbg(FYI, "Negotiate operation when server credits is non-zero. Optype: %d, server credits: %d, credits added: %d\n",
                         optype, scredits, add);
        }

        spin_lock(&server->srv_lock);
        if (server->tcpStatus == CifsNeedReconnect
            || server->tcpStatus == CifsExiting) {
                spin_unlock(&server->srv_lock);
                return;
        }
        spin_unlock(&server->srv_lock);

        switch (rc) {
        case -1:
                /* change_conf hasn't been executed */
                break;
        case 0:
                cifs_server_dbg(VFS, "Possible client or server bug - zero credits\n");
                break;
        case 1:
                cifs_server_dbg(VFS, "disabling echoes and oplocks\n");
                break;
        case 2:
                cifs_dbg(FYI, "disabling oplocks\n");
                break;
        default:
                /* change_conf rebalanced credits for different types */
                break;
        }

        trace_smb3_add_credits(server->CurrentMid,
                        server->conn_id, server->hostname, scredits, add, in_flight);
        cifs_dbg(FYI, "%s: added %u credits total=%d\n", __func__, add, scredits);
}

static void
smb2_set_credits(struct TCP_Server_Info *server, const int val)
{
        int scredits, in_flight;

        spin_lock(&server->req_lock);
        server->credits = val;
        if (val == 1)
                server->reconnect_instance++;
        scredits = server->credits;
        in_flight = server->in_flight;
        spin_unlock(&server->req_lock);

        trace_smb3_set_credits(server->CurrentMid,
                        server->conn_id, server->hostname, scredits, val, in_flight);
        cifs_dbg(FYI, "%s: set %u credits\n", __func__, val);

        /* don't log while holding the lock */
        if (val == 1)
                cifs_dbg(FYI, "set credits to 1 due to smb2 reconnect\n");
}

static int *
smb2_get_credits_field(struct TCP_Server_Info *server, const int optype)
{
        switch (optype) {
        case CIFS_ECHO_OP:
                return &server->echo_credits;
        case CIFS_OBREAK_OP:
                return &server->oplock_credits;
        default:
                return &server->credits;
        }
}

static unsigned int
smb2_get_credits(struct mid_q_entry *mid)
{
        return mid->credits_received;
}

static int
smb2_wait_mtu_credits(struct TCP_Server_Info *server, unsigned int size,
                      unsigned int *num, struct cifs_credits *credits)
{
        int rc = 0;
        unsigned int scredits, in_flight;

        spin_lock(&server->req_lock);
        while (1) {
                if (server->credits <= 0) {
                        spin_unlock(&server->req_lock);
                        cifs_num_waiters_inc(server);
                        rc = wait_event_killable(server->request_q,
                                has_credits(server, &server->credits, 1));
                        cifs_num_waiters_dec(server);
                        if (rc)
                                return rc;
                        spin_lock(&server->req_lock);
                } else {
                        spin_unlock(&server->req_lock);
                        spin_lock(&server->srv_lock);
                        if (server->tcpStatus == CifsExiting) {
                                spin_unlock(&server->srv_lock);
                                return -ENOENT;
                        }
                        spin_unlock(&server->srv_lock);

                        spin_lock(&server->req_lock);
                        scredits = server->credits;
                        /* can deadlock with reopen */
                        if (scredits <= 8) {
                                *num = SMB2_MAX_BUFFER_SIZE;
                                credits->value = 0;
                                credits->instance = 0;
                                break;
                        }

                        /* leave some credits for reopen and other ops */
                        scredits -= 8;
                        *num = min_t(unsigned int, size,
                                     scredits * SMB2_MAX_BUFFER_SIZE);

                        credits->value =
                                DIV_ROUND_UP(*num, SMB2_MAX_BUFFER_SIZE);
                        credits->instance = server->reconnect_instance;
                        server->credits -= credits->value;
                        server->in_flight++;
                        if (server->in_flight > server->max_in_flight)
                                server->max_in_flight = server->in_flight;
                        break;
                }
        }
        scredits = server->credits;
        in_flight = server->in_flight;
        spin_unlock(&server->req_lock);

        trace_smb3_wait_credits(server->CurrentMid,
                        server->conn_id, server->hostname, scredits, -(credits->value), in_flight);
        cifs_dbg(FYI, "%s: removed %u credits total=%d\n",
                        __func__, credits->value, scredits);

        return rc;
}

static int
smb2_adjust_credits(struct TCP_Server_Info *server,
                    struct cifs_credits *credits,
                    const unsigned int payload_size)
{
        int new_val = DIV_ROUND_UP(payload_size, SMB2_MAX_BUFFER_SIZE);
        int scredits, in_flight;

        if (!credits->value || credits->value == new_val)
                return 0;

        if (credits->value < new_val) {
                trace_smb3_too_many_credits(server->CurrentMid,
                                server->conn_id, server->hostname, 0, credits->value - new_val, 0);
                cifs_server_dbg(VFS, "request has less credits (%d) than required (%d)",
                                credits->value, new_val);

                return -ENOTSUPP;
        }

        spin_lock(&server->req_lock);

        if (server->reconnect_instance != credits->instance) {
                scredits = server->credits;
                in_flight = server->in_flight;
                spin_unlock(&server->req_lock);

                trace_smb3_reconnect_detected(server->CurrentMid,
                        server->conn_id, server->hostname, scredits,
                        credits->value - new_val, in_flight);
                cifs_server_dbg(VFS, "trying to return %d credits to old session\n",
                         credits->value - new_val);
                return -EAGAIN;
        }

        server->credits += credits->value - new_val;
        scredits = server->credits;
        in_flight = server->in_flight;
        spin_unlock(&server->req_lock);
        wake_up(&server->request_q);

        trace_smb3_adj_credits(server->CurrentMid,
                        server->conn_id, server->hostname, scredits,
                        credits->value - new_val, in_flight);
        cifs_dbg(FYI, "%s: adjust added %u credits total=%d\n",
                        __func__, credits->value - new_val, scredits);

        credits->value = new_val;

        return 0;
}

static __u64
smb2_get_next_mid(struct TCP_Server_Info *server)
{
        __u64 mid;
        /* for SMB2 we need the current value */
        spin_lock(&server->mid_lock);
        mid = server->CurrentMid++;
        spin_unlock(&server->mid_lock);
        return mid;
}

static void
smb2_revert_current_mid(struct TCP_Server_Info *server, const unsigned int val)
{
        spin_lock(&server->mid_lock);
        if (server->CurrentMid >= val)
                server->CurrentMid -= val;
        spin_unlock(&server->mid_lock);
}

static struct mid_q_entry *
__smb2_find_mid(struct TCP_Server_Info *server, char *buf, bool dequeue)
{
        struct mid_q_entry *mid;
        struct smb2_hdr *shdr = (struct smb2_hdr *)buf;
        __u64 wire_mid = le64_to_cpu(shdr->MessageId);

        if (shdr->ProtocolId == SMB2_TRANSFORM_PROTO_NUM) {
                cifs_server_dbg(VFS, "Encrypted frame parsing not supported yet\n");
                return NULL;
        }

        spin_lock(&server->mid_lock);
        list_for_each_entry(mid, &server->pending_mid_q, qhead) {
                if ((mid->mid == wire_mid) &&
                    (mid->mid_state == MID_REQUEST_SUBMITTED) &&
                    (mid->command == shdr->Command)) {
                        kref_get(&mid->refcount);
                        if (dequeue) {
                                list_del_init(&mid->qhead);
                                mid->mid_flags |= MID_DELETED;
                        }
                        spin_unlock(&server->mid_lock);
                        return mid;
                }
        }
        spin_unlock(&server->mid_lock);
        return NULL;
}

static struct mid_q_entry *
smb2_find_mid(struct TCP_Server_Info *server, char *buf)
{
        return __smb2_find_mid(server, buf, false);
}

static struct mid_q_entry *
smb2_find_dequeue_mid(struct TCP_Server_Info *server, char *buf)
{
        return __smb2_find_mid(server, buf, true);
}

static void
smb2_dump_detail(void *buf, struct TCP_Server_Info *server)
{
#ifdef CONFIG_CIFS_DEBUG2
        struct smb2_hdr *shdr = (struct smb2_hdr *)buf;

        cifs_server_dbg(VFS, "Cmd: %d Err: 0x%x Flags: 0x%x Mid: %llu Pid: %d\n",
                 shdr->Command, shdr->Status, shdr->Flags, shdr->MessageId,
                 shdr->Id.SyncId.ProcessId);
        cifs_server_dbg(VFS, "smb buf %p len %u\n", buf,
                 server->ops->calc_smb_size(buf));
#endif
}

static bool
smb2_need_neg(struct TCP_Server_Info *server)
{
        return server->max_read == 0;
}

static int
smb2_negotiate(const unsigned int xid,
               struct cifs_ses *ses,
               struct TCP_Server_Info *server)
{
        int rc;

        spin_lock(&server->mid_lock);
        server->CurrentMid = 0;
        spin_unlock(&server->mid_lock);
        rc = SMB2_negotiate(xid, ses, server);
        /* BB we probably don't need to retry with modern servers */
        if (rc == -EAGAIN)
                rc = -EHOSTDOWN;
        return rc;
}

static unsigned int
smb2_negotiate_wsize(struct cifs_tcon *tcon, struct smb3_fs_context *ctx)
{
        struct TCP_Server_Info *server = tcon->ses->server;
        unsigned int wsize;

        /* start with specified wsize, or default */
        wsize = ctx->wsize ? ctx->wsize : CIFS_DEFAULT_IOSIZE;
        wsize = min_t(unsigned int, wsize, server->max_write);
        if (!(server->capabilities & SMB2_GLOBAL_CAP_LARGE_MTU))
                wsize = min_t(unsigned int, wsize, SMB2_MAX_BUFFER_SIZE);

        return wsize;
}

static unsigned int
smb3_negotiate_wsize(struct cifs_tcon *tcon, struct smb3_fs_context *ctx)
{
        struct TCP_Server_Info *server = tcon->ses->server;
        unsigned int wsize;

        /* start with specified wsize, or default */
        wsize = ctx->wsize ? ctx->wsize : SMB3_DEFAULT_IOSIZE;
        wsize = min_t(unsigned int, wsize, server->max_write);
#ifdef CONFIG_CIFS_SMB_DIRECT
        if (server->rdma) {
                if (server->sign)
                        /*
                         * Account for SMB2 data transfer packet header and
                         * possible encryption header
                         */
                        wsize = min_t(unsigned int,
                                wsize,
                                server->smbd_conn->max_fragmented_send_size -
                                        SMB2_READWRITE_PDU_HEADER_SIZE -
                                        sizeof(struct smb2_transform_hdr));
                else
                        wsize = min_t(unsigned int,
                                wsize, server->smbd_conn->max_readwrite_size);
        }
#endif
        if (!(server->capabilities & SMB2_GLOBAL_CAP_LARGE_MTU))
                wsize = min_t(unsigned int, wsize, SMB2_MAX_BUFFER_SIZE);

        return wsize;
}

static unsigned int
smb2_negotiate_rsize(struct cifs_tcon *tcon, struct smb3_fs_context *ctx)
{
        struct TCP_Server_Info *server = tcon->ses->server;
        unsigned int rsize;

        /* start with specified rsize, or default */
        rsize = ctx->rsize ? ctx->rsize : CIFS_DEFAULT_IOSIZE;
        rsize = min_t(unsigned int, rsize, server->max_read);

        if (!(server->capabilities & SMB2_GLOBAL_CAP_LARGE_MTU))
                rsize = min_t(unsigned int, rsize, SMB2_MAX_BUFFER_SIZE);

        return rsize;
}

static unsigned int
smb3_negotiate_rsize(struct cifs_tcon *tcon, struct smb3_fs_context *ctx)
{
        struct TCP_Server_Info *server = tcon->ses->server;
        unsigned int rsize;

        /* start with specified rsize, or default */
        rsize = ctx->rsize ? ctx->rsize : SMB3_DEFAULT_IOSIZE;
        rsize = min_t(unsigned int, rsize, server->max_read);
#ifdef CONFIG_CIFS_SMB_DIRECT
        if (server->rdma) {
                if (server->sign)
                        /*
                         * Account for SMB2 data transfer packet header and
                         * possible encryption header
                         */
                        rsize = min_t(unsigned int,
                                rsize,
                                server->smbd_conn->max_fragmented_recv_size -
                                        SMB2_READWRITE_PDU_HEADER_SIZE -
                                        sizeof(struct smb2_transform_hdr));
                else
                        rsize = min_t(unsigned int,
                                rsize, server->smbd_conn->max_readwrite_size);
        }
#endif

        if (!(server->capabilities & SMB2_GLOBAL_CAP_LARGE_MTU))
                rsize = min_t(unsigned int, rsize, SMB2_MAX_BUFFER_SIZE);

        return rsize;
}

static int
parse_server_interfaces(struct network_interface_info_ioctl_rsp *buf,
                        size_t buf_len,
                        struct cifs_ses *ses)
{
        struct network_interface_info_ioctl_rsp *p;
        struct sockaddr_in *addr4;
        struct sockaddr_in6 *addr6;
        struct iface_info_ipv4 *p4;
        struct iface_info_ipv6 *p6;
        struct cifs_server_iface *info = NULL, *iface = NULL, *niface = NULL;
        struct cifs_server_iface tmp_iface;
        ssize_t bytes_left;
        size_t next = 0;
        int nb_iface = 0;
        int rc = 0, ret = 0;

        bytes_left = buf_len;
        p = buf;

        spin_lock(&ses->iface_lock);
        /*
         * Go through iface_list and do kref_put to remove
         * any unused ifaces. ifaces in use will be removed
         * when the last user calls a kref_put on it
         */
        list_for_each_entry_safe(iface, niface, &ses->iface_list,
                                 iface_head) {
                iface->is_active = 0;
                kref_put(&iface->refcount, release_iface);
        }
        spin_unlock(&ses->iface_lock);

        while (bytes_left >= sizeof(*p)) {
                memset(&tmp_iface, 0, sizeof(tmp_iface));
                tmp_iface.speed = le64_to_cpu(p->LinkSpeed);
                tmp_iface.rdma_capable = le32_to_cpu(p->Capability & RDMA_CAPABLE) ? 1 : 0;
                tmp_iface.rss_capable = le32_to_cpu(p->Capability & RSS_CAPABLE) ? 1 : 0;

                switch (p->Family) {
                /*
                 * The kernel and wire socket structures have the same
                 * layout and use network byte order but make the
                 * conversion explicit in case either one changes.
                 */
                case INTERNETWORK:
                        addr4 = (struct sockaddr_in *)&tmp_iface.sockaddr;
                        p4 = (struct iface_info_ipv4 *)p->Buffer;
                        addr4->sin_family = AF_INET;
                        memcpy(&addr4->sin_addr, &p4->IPv4Address, 4);

                        /* [MS-SMB2] 2.2.32.5.1.1 Clients MUST ignore these */
                        addr4->sin_port = cpu_to_be16(CIFS_PORT);

                        cifs_dbg(FYI, "%s: ipv4 %pI4\n", __func__,
                                 &addr4->sin_addr);
                        break;
                case INTERNETWORKV6:
                        addr6 = (struct sockaddr_in6 *)&tmp_iface.sockaddr;
                        p6 = (struct iface_info_ipv6 *)p->Buffer;
                        addr6->sin6_family = AF_INET6;
                        memcpy(&addr6->sin6_addr, &p6->IPv6Address, 16);

                        /* [MS-SMB2] 2.2.32.5.1.2 Clients MUST ignore these */
                        addr6->sin6_flowinfo = 0;
                        addr6->sin6_scope_id = 0;
                        addr6->sin6_port = cpu_to_be16(CIFS_PORT);

                        cifs_dbg(FYI, "%s: ipv6 %pI6\n", __func__,
                                 &addr6->sin6_addr);
                        break;
                default:
                        cifs_dbg(VFS,
                                 "%s: skipping unsupported socket family\n",
                                 __func__);
                        goto next_iface;
                }

                /*
                 * The iface_list is assumed to be sorted by speed.
                 * Check if the new interface exists in that list.
                 * NEVER change iface. it could be in use.
                 * Add a new one instead
                 */
                spin_lock(&ses->iface_lock);
                iface = niface = NULL;
                list_for_each_entry_safe(iface, niface, &ses->iface_list,
                                         iface_head) {
                        ret = iface_cmp(iface, &tmp_iface);
                        if (!ret) {
                                /* just get a ref so that it doesn't get picked/freed */
                                iface->is_active = 1;
                                kref_get(&iface->refcount);
                                spin_unlock(&ses->iface_lock);
                                goto next_iface;
                        } else if (ret < 0) {
                                /* all remaining ifaces are slower */
                                kref_get(&iface->refcount);
                                break;
                        }
                }
                spin_unlock(&ses->iface_lock);

                /* no match. insert the entry in the list */
                info = kmalloc(sizeof(struct cifs_server_iface),
                               GFP_KERNEL);
                if (!info) {
                        rc = -ENOMEM;
                        goto out;
                }
                memcpy(info, &tmp_iface, sizeof(tmp_iface));

                /* add this new entry to the list */
                kref_init(&info->refcount);
                info->is_active = 1;

                cifs_dbg(FYI, "%s: adding iface %zu\n", __func__, ses->iface_count);
                cifs_dbg(FYI, "%s: speed %zu bps\n", __func__, info->speed);
                cifs_dbg(FYI, "%s: capabilities 0x%08x\n", __func__,
                         le32_to_cpu(p->Capability));

                spin_lock(&ses->iface_lock);
                if (!list_entry_is_head(iface, &ses->iface_list, iface_head)) {
                        list_add_tail(&info->iface_head, &iface->iface_head);
                        kref_put(&iface->refcount, release_iface);
                } else
                        list_add_tail(&info->iface_head, &ses->iface_list);
                spin_unlock(&ses->iface_lock);

                ses->iface_count++;
                ses->iface_last_update = jiffies;
next_iface:
                nb_iface++;
                next = le32_to_cpu(p->Next);
                if (!next) {
                        bytes_left -= sizeof(*p);
                        break;
                }
                p = (struct network_interface_info_ioctl_rsp *)((u8 *)p+next);
                bytes_left -= next;
        }

        if (!nb_iface) {
                cifs_dbg(VFS, "%s: malformed interface info\n", __func__);
                rc = -EINVAL;
                goto out;
        }

        /* Azure rounds the buffer size up 8, to a 16 byte boundary */
        if ((bytes_left > 8) || p->Next)
                cifs_dbg(VFS, "%s: incomplete interface info\n", __func__);


        if (!ses->iface_count) {
                rc = -EINVAL;
                goto out;
        }

out:
        return rc;
}

int
SMB3_request_interfaces(const unsigned int xid, struct cifs_tcon *tcon)
{
        int rc;
        unsigned int ret_data_len = 0;
        struct network_interface_info_ioctl_rsp *out_buf = NULL;
        struct cifs_ses *ses = tcon->ses;

        rc = SMB2_ioctl(xid, tcon, NO_FILE_ID, NO_FILE_ID,
                        FSCTL_QUERY_NETWORK_INTERFACE_INFO,
                        NULL /* no data input */, 0 /* no data input */,
                        CIFSMaxBufSize, (char **)&out_buf, &ret_data_len);
        if (rc == -EOPNOTSUPP) {
                cifs_dbg(FYI,
                         "server does not support query network interfaces\n");
                goto out;
        } else if (rc != 0) {
                cifs_tcon_dbg(VFS, "error %d on ioctl to get interface list\n", rc);
                goto out;
        }

        rc = parse_server_interfaces(out_buf, ret_data_len, ses);
        if (rc)
                goto out;

out:
        kfree(out_buf);
        return rc;
}

static void
smb3_qfs_tcon(const unsigned int xid, struct cifs_tcon *tcon,
              struct cifs_sb_info *cifs_sb)
{
        int rc;
        __le16 srch_path = 0; /* Null - open root of share */
        u8 oplock = SMB2_OPLOCK_LEVEL_NONE;
        struct cifs_open_parms oparms;
        struct cifs_fid fid;
        struct cached_fid *cfid = NULL;

        oparms.tcon = tcon;
        oparms.desired_access = FILE_READ_ATTRIBUTES;
        oparms.disposition = FILE_OPEN;
        oparms.create_options = cifs_create_options(cifs_sb, 0);
        oparms.fid = &fid;
        oparms.reconnect = false;

        rc = open_cached_dir(xid, tcon, "", cifs_sb, false, &cfid);
        if (rc == 0)
                memcpy(&fid, &cfid->fid, sizeof(struct cifs_fid));
        else
                rc = SMB2_open(xid, &oparms, &srch_path, &oplock, NULL, NULL,
                               NULL, NULL);
        if (rc)
                return;

        SMB3_request_interfaces(xid, tcon);

        SMB2_QFS_attr(xid, tcon, fid.persistent_fid, fid.volatile_fid,
                        FS_ATTRIBUTE_INFORMATION);
        SMB2_QFS_attr(xid, tcon, fid.persistent_fid, fid.volatile_fid,
                        FS_DEVICE_INFORMATION);
        SMB2_QFS_attr(xid, tcon, fid.persistent_fid, fid.volatile_fid,
                        FS_VOLUME_INFORMATION);
        SMB2_QFS_attr(xid, tcon, fid.persistent_fid, fid.volatile_fid,
                        FS_SECTOR_SIZE_INFORMATION); /* SMB3 specific */
        if (cfid == NULL)
                SMB2_close(xid, tcon, fid.persistent_fid, fid.volatile_fid);
        else
                close_cached_dir(cfid);
}

static void
smb2_qfs_tcon(const unsigned int xid, struct cifs_tcon *tcon,
              struct cifs_sb_info *cifs_sb)
{
        int rc;
        __le16 srch_path = 0; /* Null - open root of share */
        u8 oplock = SMB2_OPLOCK_LEVEL_NONE;
        struct cifs_open_parms oparms;
        struct cifs_fid fid;

        oparms.tcon = tcon;
        oparms.desired_access = FILE_READ_ATTRIBUTES;
        oparms.disposition = FILE_OPEN;
        oparms.create_options = cifs_create_options(cifs_sb, 0);
        oparms.fid = &fid;
        oparms.reconnect = false;

        rc = SMB2_open(xid, &oparms, &srch_path, &oplock, NULL, NULL,
                       NULL, NULL);
        if (rc)
                return;

        SMB2_QFS_attr(xid, tcon, fid.persistent_fid, fid.volatile_fid,
                        FS_ATTRIBUTE_INFORMATION);
        SMB2_QFS_attr(xid, tcon, fid.persistent_fid, fid.volatile_fid,
                        FS_DEVICE_INFORMATION);
        SMB2_close(xid, tcon, fid.persistent_fid, fid.volatile_fid);
}

static int
smb2_is_path_accessible(const unsigned int xid, struct cifs_tcon *tcon,
                        struct cifs_sb_info *cifs_sb, const char *full_path)
{
        int rc;
        __le16 *utf16_path;
        __u8 oplock = SMB2_OPLOCK_LEVEL_NONE;
        struct cifs_open_parms oparms;
        struct cifs_fid fid;
        struct cached_fid *cfid;

        rc = open_cached_dir(xid, tcon, full_path, cifs_sb, true, &cfid);
        if (!rc) {
                if (cfid->is_valid) {
                        close_cached_dir(cfid);
                        return 0;
                }
                close_cached_dir(cfid);
        }

        utf16_path = cifs_convert_path_to_utf16(full_path, cifs_sb);
        if (!utf16_path)
                return -ENOMEM;

        oparms.tcon = tcon;
        oparms.desired_access = FILE_READ_ATTRIBUTES;
        oparms.disposition = FILE_OPEN;
        oparms.create_options = cifs_create_options(cifs_sb, 0);
        oparms.fid = &fid;
        oparms.reconnect = false;

        rc = SMB2_open(xid, &oparms, utf16_path, &oplock, NULL, NULL, NULL,
                       NULL);
        if (rc) {
                kfree(utf16_path);
                return rc;
        }

        rc = SMB2_close(xid, tcon, fid.persistent_fid, fid.volatile_fid);
        kfree(utf16_path);
        return rc;
}

static int
smb2_get_srv_inum(const unsigned int xid, struct cifs_tcon *tcon,
                  struct cifs_sb_info *cifs_sb, const char *full_path,
                  u64 *uniqueid, FILE_ALL_INFO *data)
{
        *uniqueid = le64_to_cpu(data->IndexNumber);
        return 0;
}

static int
smb2_query_file_info(const unsigned int xid, struct cifs_tcon *tcon,
                     struct cifs_fid *fid, FILE_ALL_INFO *data)
{
        int rc;
        struct smb2_file_all_info *smb2_data;

        smb2_data = kzalloc(sizeof(struct smb2_file_all_info) + PATH_MAX * 2,
                            GFP_KERNEL);
        if (smb2_data == NULL)
                return -ENOMEM;

        rc = SMB2_query_info(xid, tcon, fid->persistent_fid, fid->volatile_fid,
                             smb2_data);
        if (!rc)
                move_smb2_info_to_cifs(data, smb2_data);
        kfree(smb2_data);
        return rc;
}

#ifdef CONFIG_CIFS_XATTR
static ssize_t
move_smb2_ea_to_cifs(char *dst, size_t dst_size,
                     struct smb2_file_full_ea_info *src, size_t src_size,
                     const unsigned char *ea_name)
{
        int rc = 0;
        unsigned int ea_name_len = ea_name ? strlen(ea_name) : 0;
        char *name, *value;
        size_t buf_size = dst_size;
        size_t name_len, value_len, user_name_len;

        while (src_size > 0) {
                name_len = (size_t)src->ea_name_length;
                value_len = (size_t)le16_to_cpu(src->ea_value_length);

                if (name_len == 0)
                        break;

                if (src_size < 8 + name_len + 1 + value_len) {
                        cifs_dbg(FYI, "EA entry goes beyond length of list\n");
                        rc = -EIO;
                        goto out;
                }

                name = &src->ea_data[0];
                value = &src->ea_data[src->ea_name_length + 1];

                if (ea_name) {
                        if (ea_name_len == name_len &&
                            memcmp(ea_name, name, name_len) == 0) {
                                rc = value_len;
                                if (dst_size == 0)
                                        goto out;
                                if (dst_size < value_len) {
                                        rc = -ERANGE;
                                        goto out;
                                }
                                memcpy(dst, value, value_len);
                                goto out;
                        }
                } else {
                        /* 'user.' plus a terminating null */
                        user_name_len = 5 + 1 + name_len;

                        if (buf_size == 0) {
                                /* skip copy - calc size only */
                                rc += user_name_len;
                        } else if (dst_size >= user_name_len) {
                                dst_size -= user_name_len;
                                memcpy(dst, "user.", 5);
                                dst += 5;
                                memcpy(dst, src->ea_data, name_len);
                                dst += name_len;
                                *dst = 0;
                                ++dst;
                                rc += user_name_len;
                        } else {
                                /* stop before overrun buffer */
                                rc = -ERANGE;
                                break;
                        }
                }

                if (!src->next_entry_offset)
                        break;

                if (src_size < le32_to_cpu(src->next_entry_offset)) {
                        /* stop before overrun buffer */
                        rc = -ERANGE;
                        break;
                }
                src_size -= le32_to_cpu(src->next_entry_offset);
                src = (void *)((char *)src +
                               le32_to_cpu(src->next_entry_offset));
        }

        /* didn't find the named attribute */
        if (ea_name)
                rc = -ENODATA;

out:
        return (ssize_t)rc;
}

static ssize_t
smb2_query_eas(const unsigned int xid, struct cifs_tcon *tcon,
               const unsigned char *path, const unsigned char *ea_name,
               char *ea_data, size_t buf_size,
               struct cifs_sb_info *cifs_sb)
{
        int rc;
        struct kvec rsp_iov = {NULL, 0};
        int buftype = CIFS_NO_BUFFER;
        struct smb2_query_info_rsp *rsp;
        struct smb2_file_full_ea_info *info = NULL;

        rc = smb2_query_info_compound(xid, tcon, path,
                                      FILE_READ_EA,
                                      FILE_FULL_EA_INFORMATION,
                                      SMB2_O_INFO_FILE,
                                      CIFSMaxBufSize -
                                      MAX_SMB2_CREATE_RESPONSE_SIZE -
                                      MAX_SMB2_CLOSE_RESPONSE_SIZE,
                                      &rsp_iov, &buftype, cifs_sb);
        if (rc) {
                /*
                 * If ea_name is NULL (listxattr) and there are no EAs,
                 * return 0 as it's not an error. Otherwise, the specified
                 * ea_name was not found.
                 */
                if (!ea_name && rc == -ENODATA)
                        rc = 0;
                goto qeas_exit;
        }

        rsp = (struct smb2_query_info_rsp *)rsp_iov.iov_base;
        rc = smb2_validate_iov(le16_to_cpu(rsp->OutputBufferOffset),
                               le32_to_cpu(rsp->OutputBufferLength),
                               &rsp_iov,
                               sizeof(struct smb2_file_full_ea_info));
        if (rc)
                goto qeas_exit;

        info = (struct smb2_file_full_ea_info *)(
                        le16_to_cpu(rsp->OutputBufferOffset) + (char *)rsp);
        rc = move_smb2_ea_to_cifs(ea_data, buf_size, info,
                        le32_to_cpu(rsp->OutputBufferLength), ea_name);

 qeas_exit:
        free_rsp_buf(buftype, rsp_iov.iov_base);
        return rc;
}


static int
smb2_set_ea(const unsigned int xid, struct cifs_tcon *tcon,
            const char *path, const char *ea_name, const void *ea_value,
            const __u16 ea_value_len, const struct nls_table *nls_codepage,
            struct cifs_sb_info *cifs_sb)
{
        struct cifs_ses *ses = tcon->ses;
        struct TCP_Server_Info *server = cifs_pick_channel(ses);
        __le16 *utf16_path = NULL;
        int ea_name_len = strlen(ea_name);
        int flags = CIFS_CP_CREATE_CLOSE_OP;
        int len;
        struct smb_rqst rqst[3];
        int resp_buftype[3];
        struct kvec rsp_iov[3];
        struct kvec open_iov[SMB2_CREATE_IOV_SIZE];
        struct cifs_open_parms oparms;
        __u8 oplock = SMB2_OPLOCK_LEVEL_NONE;
        struct cifs_fid fid;
        struct kvec si_iov[SMB2_SET_INFO_IOV_SIZE];
        unsigned int size[1];
        void *data[1];
        struct smb2_file_full_ea_info *ea = NULL;
        struct kvec close_iov[1];
        struct smb2_query_info_rsp *rsp;
        int rc, used_len = 0;

        if (smb3_encryption_required(tcon))
                flags |= CIFS_TRANSFORM_REQ;

        if (ea_name_len > 255)
                return -EINVAL;

        utf16_path = cifs_convert_path_to_utf16(path, cifs_sb);
        if (!utf16_path)
                return -ENOMEM;

        memset(rqst, 0, sizeof(rqst));
        resp_buftype[0] = resp_buftype[1] = resp_buftype[2] = CIFS_NO_BUFFER;
        memset(rsp_iov, 0, sizeof(rsp_iov));

        if (ses->server->ops->query_all_EAs) {
                if (!ea_value) {
                        rc = ses->server->ops->query_all_EAs(xid, tcon, path,
                                                             ea_name, NULL, 0,
                                                             cifs_sb);
                        if (rc == -ENODATA)
                                goto sea_exit;
                } else {
                        /* If we are adding a attribute we should first check
                         * if there will be enough space available to store
                         * the new EA. If not we should not add it since we
                         * would not be able to even read the EAs back.
                         */
                        rc = smb2_query_info_compound(xid, tcon, path,
                                      FILE_READ_EA,
                                      FILE_FULL_EA_INFORMATION,
                                      SMB2_O_INFO_FILE,
                                      CIFSMaxBufSize -
                                      MAX_SMB2_CREATE_RESPONSE_SIZE -
                                      MAX_SMB2_CLOSE_RESPONSE_SIZE,
                                      &rsp_iov[1], &resp_buftype[1], cifs_sb);
                        if (rc == 0) {
                                rsp = (struct smb2_query_info_rsp *)rsp_iov[1].iov_base;
                                used_len = le32_to_cpu(rsp->OutputBufferLength);
                        }
                        free_rsp_buf(resp_buftype[1], rsp_iov[1].iov_base);
                        resp_buftype[1] = CIFS_NO_BUFFER;
                        memset(&rsp_iov[1], 0, sizeof(rsp_iov[1]));
                        rc = 0;

                        /* Use a fudge factor of 256 bytes in case we collide
                         * with a different set_EAs command.
                         */
                        if(CIFSMaxBufSize - MAX_SMB2_CREATE_RESPONSE_SIZE -
                           MAX_SMB2_CLOSE_RESPONSE_SIZE - 256 <
                           used_len + ea_name_len + ea_value_len + 1) {
                                rc = -ENOSPC;
                                goto sea_exit;
                        }
                }
        }

        /* Open */
        memset(&open_iov, 0, sizeof(open_iov));
        rqst[0].rq_iov = open_iov;
        rqst[0].rq_nvec = SMB2_CREATE_IOV_SIZE;

        memset(&oparms, 0, sizeof(oparms));
        oparms.tcon = tcon;
        oparms.desired_access = FILE_WRITE_EA;
        oparms.disposition = FILE_OPEN;
        oparms.create_options = cifs_create_options(cifs_sb, 0);
        oparms.fid = &fid;
        oparms.reconnect = false;

        rc = SMB2_open_init(tcon, server,
                            &rqst[0], &oplock, &oparms, utf16_path);
        if (rc)
                goto sea_exit;
        smb2_set_next_command(tcon, &rqst[0]);


        /* Set Info */
        memset(&si_iov, 0, sizeof(si_iov));
        rqst[1].rq_iov = si_iov;
        rqst[1].rq_nvec = 1;

        len = sizeof(*ea) + ea_name_len + ea_value_len + 1;
        ea = kzalloc(len, GFP_KERNEL);
        if (ea == NULL) {
                rc = -ENOMEM;
                goto sea_exit;
        }

        ea->ea_name_length = ea_name_len;
        ea->ea_value_length = cpu_to_le16(ea_value_len);
        memcpy(ea->ea_data, ea_name, ea_name_len + 1);
        memcpy(ea->ea_data + ea_name_len + 1, ea_value, ea_value_len);

        size[0] = len;
        data[0] = ea;

        rc = SMB2_set_info_init(tcon, server,
                                &rqst[1], COMPOUND_FID,
                                COMPOUND_FID, current->tgid,
                                FILE_FULL_EA_INFORMATION,
                                SMB2_O_INFO_FILE, 0, data, size);
        smb2_set_next_command(tcon, &rqst[1]);
        smb2_set_related(&rqst[1]);


        /* Close */
        memset(&close_iov, 0, sizeof(close_iov));
        rqst[2].rq_iov = close_iov;
        rqst[2].rq_nvec = 1;
        rc = SMB2_close_init(tcon, server,
                             &rqst[2], COMPOUND_FID, COMPOUND_FID, false);
        smb2_set_related(&rqst[2]);

        rc = compound_send_recv(xid, ses, server,
                                flags, 3, rqst,
                                resp_buftype, rsp_iov);
        /* no need to bump num_remote_opens because handle immediately closed */

 sea_exit:
        kfree(ea);
        kfree(utf16_path);
        SMB2_open_free(&rqst[0]);
        SMB2_set_info_free(&rqst[1]);
        SMB2_close_free(&rqst[2]);
        free_rsp_buf(resp_buftype[0], rsp_iov[0].iov_base);
        free_rsp_buf(resp_buftype[1], rsp_iov[1].iov_base);
        free_rsp_buf(resp_buftype[2], rsp_iov[2].iov_base);
        return rc;
}
#endif

static bool
smb2_can_echo(struct TCP_Server_Info *server)
{
        return server->echoes;
}

static void
smb2_clear_stats(struct cifs_tcon *tcon)
{
        int i;

        for (i = 0; i < NUMBER_OF_SMB2_COMMANDS; i++) {
                atomic_set(&tcon->stats.smb2_stats.smb2_com_sent[i], 0);
                atomic_set(&tcon->stats.smb2_stats.smb2_com_failed[i], 0);
        }
}

static void
smb2_dump_share_caps(struct seq_file *m, struct cifs_tcon *tcon)
{
        seq_puts(m, "\n\tShare Capabilities:");
        if (tcon->capabilities & SMB2_SHARE_CAP_DFS)
                seq_puts(m, " DFS,");
        if (tcon->capabilities & SMB2_SHARE_CAP_CONTINUOUS_AVAILABILITY)
                seq_puts(m, " CONTINUOUS AVAILABILITY,");
        if (tcon->capabilities & SMB2_SHARE_CAP_SCALEOUT)
                seq_puts(m, " SCALEOUT,");
        if (tcon->capabilities & SMB2_SHARE_CAP_CLUSTER)
                seq_puts(m, " CLUSTER,");
        if (tcon->capabilities & SMB2_SHARE_CAP_ASYMMETRIC)
                seq_puts(m, " ASYMMETRIC,");
        if (tcon->capabilities == 0)
                seq_puts(m, " None");
        if (tcon->ss_flags & SSINFO_FLAGS_ALIGNED_DEVICE)
                seq_puts(m, " Aligned,");
        if (tcon->ss_flags & SSINFO_FLAGS_PARTITION_ALIGNED_ON_DEVICE)
                seq_puts(m, " Partition Aligned,");
        if (tcon->ss_flags & SSINFO_FLAGS_NO_SEEK_PENALTY)
                seq_puts(m, " SSD,");
        if (tcon->ss_flags & SSINFO_FLAGS_TRIM_ENABLED)
                seq_puts(m, " TRIM-support,");

        seq_printf(m, "\tShare Flags: 0x%x", tcon->share_flags);
        seq_printf(m, "\n\ttid: 0x%x", tcon->tid);
        if (tcon->perf_sector_size)
                seq_printf(m, "\tOptimal sector size: 0x%x",
                           tcon->perf_sector_size);
        seq_printf(m, "\tMaximal Access: 0x%x", tcon->maximal_access);
}

static void
smb2_print_stats(struct seq_file *m, struct cifs_tcon *tcon)
{
        atomic_t *sent = tcon->stats.smb2_stats.smb2_com_sent;
        atomic_t *failed = tcon->stats.smb2_stats.smb2_com_failed;

        /*
         *  Can't display SMB2_NEGOTIATE, SESSION_SETUP, LOGOFF, CANCEL and ECHO
         *  totals (requests sent) since those SMBs are per-session not per tcon
         */
        seq_printf(m, "\nBytes read: %llu  Bytes written: %llu",
                   (long long)(tcon->bytes_read),
                   (long long)(tcon->bytes_written));
        seq_printf(m, "\nOpen files: %d total (local), %d open on server",
                   atomic_read(&tcon->num_local_opens),
                   atomic_read(&tcon->num_remote_opens));
        seq_printf(m, "\nTreeConnects: %d total %d failed",
                   atomic_read(&sent[SMB2_TREE_CONNECT_HE]),
                   atomic_read(&failed[SMB2_TREE_CONNECT_HE]));
        seq_printf(m, "\nTreeDisconnects: %d total %d failed",
                   atomic_read(&sent[SMB2_TREE_DISCONNECT_HE]),
                   atomic_read(&failed[SMB2_TREE_DISCONNECT_HE]));
        seq_printf(m, "\nCreates: %d total %d failed",
                   atomic_read(&sent[SMB2_CREATE_HE]),
                   atomic_read(&failed[SMB2_CREATE_HE]));
        seq_printf(m, "\nCloses: %d total %d failed",
                   atomic_read(&sent[SMB2_CLOSE_HE]),
                   atomic_read(&failed[SMB2_CLOSE_HE]));
        seq_printf(m, "\nFlushes: %d total %d failed",
                   atomic_read(&sent[SMB2_FLUSH_HE]),
                   atomic_read(&failed[SMB2_FLUSH_HE]));
        seq_printf(m, "\nReads: %d total %d failed",
                   atomic_read(&sent[SMB2_READ_HE]),
                   atomic_read(&failed[SMB2_READ_HE]));
        seq_printf(m, "\nWrites: %d total %d failed",
                   atomic_read(&sent[SMB2_WRITE_HE]),
                   atomic_read(&failed[SMB2_WRITE_HE]));
        seq_printf(m, "\nLocks: %d total %d failed",
                   atomic_read(&sent[SMB2_LOCK_HE]),
                   atomic_read(&failed[SMB2_LOCK_HE]));
        seq_printf(m, "\nIOCTLs: %d total %d failed",
                   atomic_read(&sent[SMB2_IOCTL_HE]),
                   atomic_read(&failed[SMB2_IOCTL_HE]));
        seq_printf(m, "\nQueryDirectories: %d total %d failed",
                   atomic_read(&sent[SMB2_QUERY_DIRECTORY_HE]),
                   atomic_read(&failed[SMB2_QUERY_DIRECTORY_HE]));
        seq_printf(m, "\nChangeNotifies: %d total %d failed",
                   atomic_read(&sent[SMB2_CHANGE_NOTIFY_HE]),
                   atomic_read(&failed[SMB2_CHANGE_NOTIFY_HE]));
        seq_printf(m, "\nQueryInfos: %d total %d failed",
                   atomic_read(&sent[SMB2_QUERY_INFO_HE]),
                   atomic_read(&failed[SMB2_QUERY_INFO_HE]));
        seq_printf(m, "\nSetInfos: %d total %d failed",
                   atomic_read(&sent[SMB2_SET_INFO_HE]),
                   atomic_read(&failed[SMB2_SET_INFO_HE]));
        seq_printf(m, "\nOplockBreaks: %d sent %d failed",
                   atomic_read(&sent[SMB2_OPLOCK_BREAK_HE]),
                   atomic_read(&failed[SMB2_OPLOCK_BREAK_HE]));
}

static void
smb2_set_fid(struct cifsFileInfo *cfile, struct cifs_fid *fid, __u32 oplock)
{
        struct cifsInodeInfo *cinode = CIFS_I(d_inode(cfile->dentry));
        struct TCP_Server_Info *server = tlink_tcon(cfile->tlink)->ses->server;

        cfile->fid.persistent_fid = fid->persistent_fid;
        cfile->fid.volatile_fid = fid->volatile_fid;
        cfile->fid.access = fid->access;
#ifdef CONFIG_CIFS_DEBUG2
        cfile->fid.mid = fid->mid;
#endif /* CIFS_DEBUG2 */
        server->ops->set_oplock_level(cinode, oplock, fid->epoch,
                                      &fid->purge_cache);
        cinode->can_cache_brlcks = CIFS_CACHE_WRITE(cinode);
        memcpy(cfile->fid.create_guid, fid->create_guid, 16);
}

static void
smb2_close_file(const unsigned int xid, struct cifs_tcon *tcon,
                struct cifs_fid *fid)
{
        SMB2_close(xid, tcon, fid->persistent_fid, fid->volatile_fid);
}

static void
smb2_close_getattr(const unsigned int xid, struct cifs_tcon *tcon,
                   struct cifsFileInfo *cfile)
{
        struct smb2_file_network_open_info file_inf;
        struct inode *inode;
        int rc;

        rc = __SMB2_close(xid, tcon, cfile->fid.persistent_fid,
                   cfile->fid.volatile_fid, &file_inf);
        if (rc)
                return;

        inode = d_inode(cfile->dentry);

        spin_lock(&inode->i_lock);
        CIFS_I(inode)->time = jiffies;

        /* Creation time should not need to be updated on close */
        if (file_inf.LastWriteTime)
                inode->i_mtime = cifs_NTtimeToUnix(file_inf.LastWriteTime);
        if (file_inf.ChangeTime)
                inode->i_ctime = cifs_NTtimeToUnix(file_inf.ChangeTime);
        if (file_inf.LastAccessTime)
                inode->i_atime = cifs_NTtimeToUnix(file_inf.LastAccessTime);

        /*
         * i_blocks is not related to (i_size / i_blksize),
         * but instead 512 byte (2**9) size is required for
         * calculating num blocks.
         */
        if (le64_to_cpu(file_inf.AllocationSize) > 4096)
                inode->i_blocks =
                        (512 - 1 + le64_to_cpu(file_inf.AllocationSize)) >> 9;

        /* End of file and Attributes should not have to be updated on close */
        spin_unlock(&inode->i_lock);
}

static int
SMB2_request_res_key(const unsigned int xid, struct cifs_tcon *tcon,
                     u64 persistent_fid, u64 volatile_fid,
                     struct copychunk_ioctl *pcchunk)
{
        int rc;
        unsigned int ret_data_len;
        struct resume_key_req *res_key;

        rc = SMB2_ioctl(xid, tcon, persistent_fid, volatile_fid,
                        FSCTL_SRV_REQUEST_RESUME_KEY, NULL, 0 /* no input */,
                        CIFSMaxBufSize, (char **)&res_key, &ret_data_len);

        if (rc == -EOPNOTSUPP) {
                pr_warn_once("Server share %s does not support copy range\n", tcon->treeName);
                goto req_res_key_exit;
        } else if (rc) {
                cifs_tcon_dbg(VFS, "refcpy ioctl error %d getting resume key\n", rc);
                goto req_res_key_exit;
        }
        if (ret_data_len < sizeof(struct resume_key_req)) {
                cifs_tcon_dbg(VFS, "Invalid refcopy resume key length\n");
                rc = -EINVAL;
                goto req_res_key_exit;
        }
        memcpy(pcchunk->SourceKey, res_key->ResumeKey, COPY_CHUNK_RES_KEY_SIZE);

req_res_key_exit:
        kfree(res_key);
        return rc;
}

struct iqi_vars {
        struct smb_rqst rqst[3];
        struct kvec rsp_iov[3];
        struct kvec open_iov[SMB2_CREATE_IOV_SIZE];
        struct kvec qi_iov[1];
        struct kvec io_iov[SMB2_IOCTL_IOV_SIZE];
        struct kvec si_iov[SMB2_SET_INFO_IOV_SIZE];
        struct kvec close_iov[1];
};

static int
smb2_ioctl_query_info(const unsigned int xid,
                      struct cifs_tcon *tcon,
                      struct cifs_sb_info *cifs_sb,
                      __le16 *path, int is_dir,
                      unsigned long p)
{
        struct iqi_vars *vars;
        struct smb_rqst *rqst;
        struct kvec *rsp_iov;
        struct cifs_ses *ses = tcon->ses;
        struct TCP_Server_Info *server = cifs_pick_channel(ses);
        char __user *arg = (char __user *)p;
        struct smb_query_info qi;
        struct smb_query_info __user *pqi;
        int rc = 0;
        int flags = CIFS_CP_CREATE_CLOSE_OP;
        struct smb2_query_info_rsp *qi_rsp = NULL;
        struct smb2_ioctl_rsp *io_rsp = NULL;
        void *buffer = NULL;
        int resp_buftype[3];
        struct cifs_open_parms oparms;
        u8 oplock = SMB2_OPLOCK_LEVEL_NONE;
        struct cifs_fid fid;
        unsigned int size[2];
        void *data[2];
        int create_options = is_dir ? CREATE_NOT_FILE : CREATE_NOT_DIR;
        void (*free_req1_func)(struct smb_rqst *r);

        vars = kzalloc(sizeof(*vars), GFP_ATOMIC);
        if (vars == NULL)
                return -ENOMEM;
        rqst = &vars->rqst[0];
        rsp_iov = &vars->rsp_iov[0];

        resp_buftype[0] = resp_buftype[1] = resp_buftype[2] = CIFS_NO_BUFFER;

        if (copy_from_user(&qi, arg, sizeof(struct smb_query_info))) {
                rc = -EFAULT;
                goto free_vars;
        }
        if (qi.output_buffer_length > 1024) {
                rc = -EINVAL;
                goto free_vars;
        }

        if (!ses || !server) {
                rc = -EIO;
                goto free_vars;
        }

        if (smb3_encryption_required(tcon))
                flags |= CIFS_TRANSFORM_REQ;

        if (qi.output_buffer_length) {
                buffer = memdup_user(arg + sizeof(struct smb_query_info), qi.output_buffer_length);
                if (IS_ERR(buffer)) {
                        rc = PTR_ERR(buffer);
                        goto free_vars;
                }
        }

        /* Open */
        rqst[0].rq_iov = &vars->open_iov[0];
        rqst[0].rq_nvec = SMB2_CREATE_IOV_SIZE;

        memset(&oparms, 0, sizeof(oparms));
        oparms.tcon = tcon;
        oparms.disposition = FILE_OPEN;
        oparms.create_options = cifs_create_options(cifs_sb, create_options);
        oparms.fid = &fid;
        oparms.reconnect = false;

        if (qi.flags & PASSTHRU_FSCTL) {
                switch (qi.info_type & FSCTL_DEVICE_ACCESS_MASK) {
                case FSCTL_DEVICE_ACCESS_FILE_READ_WRITE_ACCESS:
                        oparms.desired_access = FILE_READ_DATA | FILE_WRITE_DATA | FILE_READ_ATTRIBUTES | SYNCHRONIZE;
                        break;
                case FSCTL_DEVICE_ACCESS_FILE_ANY_ACCESS:
                        oparms.desired_access = GENERIC_ALL;
                        break;
                case FSCTL_DEVICE_ACCESS_FILE_READ_ACCESS:
                        oparms.desired_access = GENERIC_READ;
                        break;
                case FSCTL_DEVICE_ACCESS_FILE_WRITE_ACCESS:
                        oparms.desired_access = GENERIC_WRITE;
                        break;
                }
        } else if (qi.flags & PASSTHRU_SET_INFO) {
                oparms.desired_access = GENERIC_WRITE;
        } else {
                oparms.desired_access = FILE_READ_ATTRIBUTES | READ_CONTROL;
        }

        rc = SMB2_open_init(tcon, server,
                            &rqst[0], &oplock, &oparms, path);
        if (rc)
                goto free_output_buffer;
        smb2_set_next_command(tcon, &rqst[0]);

        /* Query */
        if (qi.flags & PASSTHRU_FSCTL) {
                /* Can eventually relax perm check since server enforces too */
                if (!capable(CAP_SYS_ADMIN)) {
                        rc = -EPERM;
                        goto free_open_req;
                }
                rqst[1].rq_iov = &vars->io_iov[0];
                rqst[1].rq_nvec = SMB2_IOCTL_IOV_SIZE;

                rc = SMB2_ioctl_init(tcon, server, &rqst[1], COMPOUND_FID, COMPOUND_FID,
                                     qi.info_type, buffer, qi.output_buffer_length,
                                     CIFSMaxBufSize - MAX_SMB2_CREATE_RESPONSE_SIZE -
                                     MAX_SMB2_CLOSE_RESPONSE_SIZE);
                free_req1_func = SMB2_ioctl_free;
        } else if (qi.flags == PASSTHRU_SET_INFO) {
                /* Can eventually relax perm check since server enforces too */
                if (!capable(CAP_SYS_ADMIN)) {
                        rc = -EPERM;
                        goto free_open_req;
                }
                if (qi.output_buffer_length < 8) {
                        rc = -EINVAL;
                        goto free_open_req;
                }
                rqst[1].rq_iov = &vars->si_iov[0];
                rqst[1].rq_nvec = 1;

                /* MS-FSCC 2.4.13 FileEndOfFileInformation */
                size[0] = 8;
                data[0] = buffer;

                rc = SMB2_set_info_init(tcon, server, &rqst[1], COMPOUND_FID, COMPOUND_FID,
                                        current->tgid, FILE_END_OF_FILE_INFORMATION,
                                        SMB2_O_INFO_FILE, 0, data, size);
                free_req1_func = SMB2_set_info_free;
        } else if (qi.flags == PASSTHRU_QUERY_INFO) {
                rqst[1].rq_iov = &vars->qi_iov[0];
                rqst[1].rq_nvec = 1;

                rc = SMB2_query_info_init(tcon, server,
                                  &rqst[1], COMPOUND_FID,
                                  COMPOUND_FID, qi.file_info_class,
                                  qi.info_type, qi.additional_information,
                                  qi.input_buffer_length,
                                  qi.output_buffer_length, buffer);
                free_req1_func = SMB2_query_info_free;
        } else { /* unknown flags */
                cifs_tcon_dbg(VFS, "Invalid passthru query flags: 0x%x\n",
                              qi.flags);
                rc = -EINVAL;
        }

        if (rc)
                goto free_open_req;
        smb2_set_next_command(tcon, &rqst[1]);
        smb2_set_related(&rqst[1]);

        /* Close */
        rqst[2].rq_iov = &vars->close_iov[0];
        rqst[2].rq_nvec = 1;

        rc = SMB2_close_init(tcon, server,
                             &rqst[2], COMPOUND_FID, COMPOUND_FID, false);
        if (rc)
                goto free_req_1;
        smb2_set_related(&rqst[2]);

        rc = compound_send_recv(xid, ses, server,
                                flags, 3, rqst,
                                resp_buftype, rsp_iov);
        if (rc)
                goto out;

        /* No need to bump num_remote_opens since handle immediately closed */
        if (qi.flags & PASSTHRU_FSCTL) {
                pqi = (struct smb_query_info __user *)arg;
                io_rsp = (struct smb2_ioctl_rsp *)rsp_iov[1].iov_base;
                if (le32_to_cpu(io_rsp->OutputCount) < qi.input_buffer_length)
                        qi.input_buffer_length = le32_to_cpu(io_rsp->OutputCount);
                if (qi.input_buffer_length > 0 &&
                    le32_to_cpu(io_rsp->OutputOffset) + qi.input_buffer_length
                    > rsp_iov[1].iov_len) {
                        rc = -EFAULT;
                        goto out;
                }

                if (copy_to_user(&pqi->input_buffer_length,
                                 &qi.input_buffer_length,
                                 sizeof(qi.input_buffer_length))) {
                        rc = -EFAULT;
                        goto out;
                }

                if (copy_to_user((void __user *)pqi + sizeof(struct smb_query_info),
                                 (const void *)io_rsp + le32_to_cpu(io_rsp->OutputOffset),
                                 qi.input_buffer_length))
                        rc = -EFAULT;
        } else {
                pqi = (struct smb_query_info __user *)arg;
                qi_rsp = (struct smb2_query_info_rsp *)rsp_iov[1].iov_base;
                if (le32_to_cpu(qi_rsp->OutputBufferLength) < qi.input_buffer_length)
                        qi.input_buffer_length = le32_to_cpu(qi_rsp->OutputBufferLength);
                if (copy_to_user(&pqi->input_buffer_length,
                                 &qi.input_buffer_length,
                                 sizeof(qi.input_buffer_length))) {
                        rc = -EFAULT;
                        goto out;
                }

                if (copy_to_user(pqi + 1, qi_rsp->Buffer,
                                 qi.input_buffer_length))
                        rc = -EFAULT;
        }

out:
        free_rsp_buf(resp_buftype[0], rsp_iov[0].iov_base);
        free_rsp_buf(resp_buftype[1], rsp_iov[1].iov_base);
        free_rsp_buf(resp_buftype[2], rsp_iov[2].iov_base);
        SMB2_close_free(&rqst[2]);
free_req_1:
        free_req1_func(&rqst[1]);
free_open_req:
        SMB2_open_free(&rqst[0]);
free_output_buffer:
        kfree(buffer);
free_vars:
        kfree(vars);
        return rc;
}

static ssize_t
smb2_copychunk_range(const unsigned int xid,
                        struct cifsFileInfo *srcfile,
                        struct cifsFileInfo *trgtfile, u64 src_off,
                        u64 len, u64 dest_off)
{
        int rc;
        unsigned int ret_data_len;
        struct copychunk_ioctl *pcchunk;
        struct copychunk_ioctl_rsp *retbuf = NULL;
        struct cifs_tcon *tcon;
        int chunks_copied = 0;
        bool chunk_sizes_updated = false;
        ssize_t bytes_written, total_bytes_written = 0;

        pcchunk = kmalloc(sizeof(struct copychunk_ioctl), GFP_KERNEL);
        if (pcchunk == NULL)
                return -ENOMEM;

        cifs_dbg(FYI, "%s: about to call request res key\n", __func__);
        /* Request a key from the server to identify the source of the copy */
        rc = SMB2_request_res_key(xid, tlink_tcon(srcfile->tlink),
                                srcfile->fid.persistent_fid,
                                srcfile->fid.volatile_fid, pcchunk);

        /* Note: request_res_key sets res_key null only if rc !=0 */
        if (rc)
                goto cchunk_out;

        /* For now array only one chunk long, will make more flexible later */
        pcchunk->ChunkCount = cpu_to_le32(1);
        pcchunk->Reserved = 0;
        pcchunk->Reserved2 = 0;

        tcon = tlink_tcon(trgtfile->tlink);

        while (len > 0) {
                pcchunk->SourceOffset = cpu_to_le64(src_off);
                pcchunk->TargetOffset = cpu_to_le64(dest_off);
                pcchunk->Length =
                        cpu_to_le32(min_t(u32, len, tcon->max_bytes_chunk));

                /* Request server copy to target from src identified by key */
                kfree(retbuf);
                retbuf = NULL;
                rc = SMB2_ioctl(xid, tcon, trgtfile->fid.persistent_fid,
                        trgtfile->fid.volatile_fid, FSCTL_SRV_COPYCHUNK_WRITE,
                        (char *)pcchunk, sizeof(struct copychunk_ioctl),
                        CIFSMaxBufSize, (char **)&retbuf, &ret_data_len);
                if (rc == 0) {
                        if (ret_data_len !=
                                        sizeof(struct copychunk_ioctl_rsp)) {
                                cifs_tcon_dbg(VFS, "Invalid cchunk response size\n");
                                rc = -EIO;
                                goto cchunk_out;
                        }
                        if (retbuf->TotalBytesWritten == 0) {
                                cifs_dbg(FYI, "no bytes copied\n");
                                rc = -EIO;
                                goto cchunk_out;
                        }
                        /*
                         * Check if server claimed to write more than we asked
                         */
                        if (le32_to_cpu(retbuf->TotalBytesWritten) >
                            le32_to_cpu(pcchunk->Length)) {
                                cifs_tcon_dbg(VFS, "Invalid copy chunk response\n");
                                rc = -EIO;
                                goto cchunk_out;
                        }
                        if (le32_to_cpu(retbuf->ChunksWritten) != 1) {
                                cifs_tcon_dbg(VFS, "Invalid num chunks written\n");
                                rc = -EIO;
                                goto cchunk_out;
                        }
                        chunks_copied++;

                        bytes_written = le32_to_cpu(retbuf->TotalBytesWritten);
                        src_off += bytes_written;
                        dest_off += bytes_written;
                        len -= bytes_written;
                        total_bytes_written += bytes_written;

                        cifs_dbg(FYI, "Chunks %d PartialChunk %d Total %zu\n",
                                le32_to_cpu(retbuf->ChunksWritten),
                                le32_to_cpu(retbuf->ChunkBytesWritten),
                                bytes_written);
                } else if (rc == -EINVAL) {
                        if (ret_data_len != sizeof(struct copychunk_ioctl_rsp))
                                goto cchunk_out;

                        cifs_dbg(FYI, "MaxChunks %d BytesChunk %d MaxCopy %d\n",
                                le32_to_cpu(retbuf->ChunksWritten),
                                le32_to_cpu(retbuf->ChunkBytesWritten),
                                le32_to_cpu(retbuf->TotalBytesWritten));

                        /*
                         * Check if this is the first request using these sizes,
                         * (ie check if copy succeed once with original sizes
                         * and check if the server gave us different sizes after
                         * we already updated max sizes on previous request).
                         * if not then why is the server returning an error now
                         */
                        if ((chunks_copied != 0) || chunk_sizes_updated)
                                goto cchunk_out;

                        /* Check that server is not asking us to grow size */
                        if (le32_to_cpu(retbuf->ChunkBytesWritten) <
                                        tcon->max_bytes_chunk)
                                tcon->max_bytes_chunk =
                                        le32_to_cpu(retbuf->ChunkBytesWritten);
                        else
                                goto cchunk_out; /* server gave us bogus size */

                        /* No need to change MaxChunks since already set to 1 */
                        chunk_sizes_updated = true;
                } else
                        goto cchunk_out;
        }

cchunk_out:
        kfree(pcchunk);
        kfree(retbuf);
        if (rc)
                return rc;
        else
                return total_bytes_written;
}

static int
smb2_flush_file(const unsigned int xid, struct cifs_tcon *tcon,
                struct cifs_fid *fid)
{
        return SMB2_flush(xid, tcon, fid->persistent_fid, fid->volatile_fid);
}

static unsigned int
smb2_read_data_offset(char *buf)
{
        struct smb2_read_rsp *rsp = (struct smb2_read_rsp *)buf;

        return rsp->DataOffset;
}

static unsigned int
smb2_read_data_length(char *buf, bool in_remaining)
{
        struct smb2_read_rsp *rsp = (struct smb2_read_rsp *)buf;

        if (in_remaining)
                return le32_to_cpu(rsp->DataRemaining);

        return le32_to_cpu(rsp->DataLength);
}


static int
smb2_sync_read(const unsigned int xid, struct cifs_fid *pfid,
               struct cifs_io_parms *parms, unsigned int *bytes_read,
               char **buf, int *buf_type)
{
        parms->persistent_fid = pfid->persistent_fid;
        parms->volatile_fid = pfid->volatile_fid;
        return SMB2_read(xid, parms, bytes_read, buf, buf_type);
}

static int
smb2_sync_write(const unsigned int xid, struct cifs_fid *pfid,
                struct cifs_io_parms *parms, unsigned int *written,
                struct kvec *iov, unsigned long nr_segs)
{

        parms->persistent_fid = pfid->persistent_fid;
        parms->volatile_fid = pfid->volatile_fid;
        return SMB2_write(xid, parms, written, iov, nr_segs);
}

/* Set or clear the SPARSE_FILE attribute based on value passed in setsparse */
static bool smb2_set_sparse(const unsigned int xid, struct cifs_tcon *tcon,
                struct cifsFileInfo *cfile, struct inode *inode, __u8 setsparse)
{
        struct cifsInodeInfo *cifsi;
        int rc;

        cifsi = CIFS_I(inode);

        /* if file already sparse don't bother setting sparse again */
        if ((cifsi->cifsAttrs & FILE_ATTRIBUTE_SPARSE_FILE) && setsparse)
                return true; /* already sparse */

        if (!(cifsi->cifsAttrs & FILE_ATTRIBUTE_SPARSE_FILE) && !setsparse)
                return true; /* already not sparse */

        /*
         * Can't check for sparse support on share the usual way via the
         * FS attribute info (FILE_SUPPORTS_SPARSE_FILES) on the share
         * since Samba server doesn't set the flag on the share, yet
         * supports the set sparse FSCTL and returns sparse correctly
         * in the file attributes. If we fail setting sparse though we
         * mark that server does not support sparse files for this share
         * to avoid repeatedly sending the unsupported fsctl to server
         * if the file is repeatedly extended.
         */
        if (tcon->broken_sparse_sup)
                return false;

        rc = SMB2_ioctl(xid, tcon, cfile->fid.persistent_fid,
                        cfile->fid.volatile_fid, FSCTL_SET_SPARSE,
                        &setsparse, 1, CIFSMaxBufSize, NULL, NULL);
        if (rc) {
                tcon->broken_sparse_sup = true;
                cifs_dbg(FYI, "set sparse rc = %d\n", rc);
                return false;
        }

        if (setsparse)
                cifsi->cifsAttrs |= FILE_ATTRIBUTE_SPARSE_FILE;
        else
                cifsi->cifsAttrs &= (~FILE_ATTRIBUTE_SPARSE_FILE);

        return true;
}

static int
smb2_set_file_size(const unsigned int xid, struct cifs_tcon *tcon,
                   struct cifsFileInfo *cfile, __u64 size, bool set_alloc)
{
        __le64 eof = cpu_to_le64(size);
        struct inode *inode;

        /*
         * If extending file more than one page make sparse. Many Linux fs
         * make files sparse by default when extending via ftruncate
         */
        inode = d_inode(cfile->dentry);

        if (!set_alloc && (size > inode->i_size + 8192)) {
                __u8 set_sparse = 1;

                /* whether set sparse succeeds or not, extend the file */
                smb2_set_sparse(xid, tcon, cfile, inode, set_sparse);
        }

        return SMB2_set_eof(xid, tcon, cfile->fid.persistent_fid,
                            cfile->fid.volatile_fid, cfile->pid, &eof);
}

static int
smb2_duplicate_extents(const unsigned int xid,
                        struct cifsFileInfo *srcfile,
                        struct cifsFileInfo *trgtfile, u64 src_off,
                        u64 len, u64 dest_off)
{
        int rc;
        unsigned int ret_data_len;
        struct inode *inode;
        struct duplicate_extents_to_file dup_ext_buf;
        struct cifs_tcon *tcon = tlink_tcon(trgtfile->tlink);

        /* server fileays advertise duplicate extent support with this flag */
        if ((le32_to_cpu(tcon->fsAttrInfo.Attributes) &
             FILE_SUPPORTS_BLOCK_REFCOUNTING) == 0)
                return -EOPNOTSUPP;

        dup_ext_buf.VolatileFileHandle = srcfile->fid.volatile_fid;
        dup_ext_buf.PersistentFileHandle = srcfile->fid.persistent_fid;
        dup_ext_buf.SourceFileOffset = cpu_to_le64(src_off);
        dup_ext_buf.TargetFileOffset = cpu_to_le64(dest_off);
        dup_ext_buf.ByteCount = cpu_to_le64(len);
        cifs_dbg(FYI, "Duplicate extents: src off %lld dst off %lld len %lld\n",
                src_off, dest_off, len);

        inode = d_inode(trgtfile->dentry);
        if (inode->i_size < dest_off + len) {
                rc = smb2_set_file_size(xid, tcon, trgtfile, dest_off + len, false);
                if (rc)
                        goto duplicate_extents_out;

                /*
                 * Although also could set plausible allocation size (i_blocks)
                 * here in addition to setting the file size, in reflink
                 * it is likely that the target file is sparse. Its allocation
                 * size will be queried on next revalidate, but it is important
                 * to make sure that file's cached size is updated immediately
                 */
                cifs_setsize(inode, dest_off + len);
        }
        rc = SMB2_ioctl(xid, tcon, trgtfile->fid.persistent_fid,
                        trgtfile->fid.volatile_fid,
                        FSCTL_DUPLICATE_EXTENTS_TO_FILE,
                        (char *)&dup_ext_buf,
                        sizeof(struct duplicate_extents_to_file),
                        CIFSMaxBufSize, NULL,
                        &ret_data_len);

        if (ret_data_len > 0)
                cifs_dbg(FYI, "Non-zero response length in duplicate extents\n");

duplicate_extents_out:
        return rc;
}

static int
smb2_set_compression(const unsigned int xid, struct cifs_tcon *tcon,
                   struct cifsFileInfo *cfile)
{
        return SMB2_set_compression(xid, tcon, cfile->fid.persistent_fid,
                            cfile->fid.volatile_fid);
}

static int
smb3_set_integrity(const unsigned int xid, struct cifs_tcon *tcon,
                   struct cifsFileInfo *cfile)
{
        struct fsctl_set_integrity_information_req integr_info;
        unsigned int ret_data_len;

        integr_info.ChecksumAlgorithm = cpu_to_le16(CHECKSUM_TYPE_UNCHANGED);
        integr_info.Flags = 0;
        integr_info.Reserved = 0;

        return SMB2_ioctl(xid, tcon, cfile->fid.persistent_fid,
                        cfile->fid.volatile_fid,
                        FSCTL_SET_INTEGRITY_INFORMATION,
                        (char *)&integr_info,
                        sizeof(struct fsctl_set_integrity_information_req),
                        CIFSMaxBufSize, NULL,
                        &ret_data_len);

}

/* GMT Token is @GMT-YYYY.MM.DD-HH.MM.SS Unicode which is 48 bytes + null */
#define GMT_TOKEN_SIZE 50

#define MIN_SNAPSHOT_ARRAY_SIZE 16 /* See MS-SMB2 section 3.3.5.15.1 */

/*
 * Input buffer contains (empty) struct smb_snapshot array with size filled in
 * For output see struct SRV_SNAPSHOT_ARRAY in MS-SMB2 section 2.2.32.2
 */
static int
smb3_enum_snapshots(const unsigned int xid, struct cifs_tcon *tcon,
                   struct cifsFileInfo *cfile, void __user *ioc_buf)
{
        char *retbuf = NULL;
        unsigned int ret_data_len = 0;
        int rc;
        u32 max_response_size;
        struct smb_snapshot_array snapshot_in;

        /*
         * On the first query to enumerate the list of snapshots available
         * for this volume the buffer begins with 0 (number of snapshots
         * which can be returned is zero since at that point we do not know
         * how big the buffer needs to be). On the second query,
         * it (ret_data_len) is set to number of snapshots so we can
         * know to set the maximum response size larger (see below).
         */
        if (get_user(ret_data_len, (unsigned int __user *)ioc_buf))
                return -EFAULT;

        /*
         * Note that for snapshot queries that servers like Azure expect that
         * the first query be minimal size (and just used to get the number/size
         * of previous versions) so response size must be specified as EXACTLY
         * sizeof(struct snapshot_array) which is 16 when rounded up to multiple
         * of eight bytes.
         */
        if (ret_data_len == 0)
                max_response_size = MIN_SNAPSHOT_ARRAY_SIZE;
        else
                max_response_size = CIFSMaxBufSize;

        rc = SMB2_ioctl(xid, tcon, cfile->fid.persistent_fid,
                        cfile->fid.volatile_fid,
                        FSCTL_SRV_ENUMERATE_SNAPSHOTS,
                        NULL, 0 /* no input data */, max_response_size,
                        (char **)&retbuf,
                        &ret_data_len);
        cifs_dbg(FYI, "enum snaphots ioctl returned %d and ret buflen is %d\n",
                        rc, ret_data_len);
        if (rc)
                return rc;

        if (ret_data_len && (ioc_buf != NULL) && (retbuf != NULL)) {
                /* Fixup buffer */
                if (copy_from_user(&snapshot_in, ioc_buf,
                    sizeof(struct smb_snapshot_array))) {
                        rc = -EFAULT;
                        kfree(retbuf);
                        return rc;
                }

                /*
                 * Check for min size, ie not large enough to fit even one GMT
                 * token (snapshot).  On the first ioctl some users may pass in
                 * smaller size (or zero) to simply get the size of the array
                 * so the user space caller can allocate sufficient memory
                 * and retry the ioctl again with larger array size sufficient
                 * to hold all of the snapshot GMT tokens on the second try.
                 */
                if (snapshot_in.snapshot_array_size < GMT_TOKEN_SIZE)
                        ret_data_len = sizeof(struct smb_snapshot_array);

                /*
                 * We return struct SRV_SNAPSHOT_ARRAY, followed by
                 * the snapshot array (of 50 byte GMT tokens) each
                 * representing an available previous version of the data
                 */
                if (ret_data_len > (snapshot_in.snapshot_array_size +
                                        sizeof(struct smb_snapshot_array)))
                        ret_data_len = snapshot_in.snapshot_array_size +
                                        sizeof(struct smb_snapshot_array);

                if (copy_to_user(ioc_buf, retbuf, ret_data_len))
                        rc = -EFAULT;
        }

        kfree(retbuf);
        return rc;
}



static int
smb3_notify(const unsigned int xid, struct file *pfile,
            void __user *ioc_buf)
{
        struct smb3_notify notify;
        struct dentry *dentry = pfile->f_path.dentry;
        struct inode *inode = file_inode(pfile);
        struct cifs_sb_info *cifs_sb = CIFS_SB(inode->i_sb);
        struct cifs_open_parms oparms;
        struct cifs_fid fid;
        struct cifs_tcon *tcon;
        const unsigned char *path;
        void *page = alloc_dentry_path();
        __le16 *utf16_path = NULL;
        u8 oplock = SMB2_OPLOCK_LEVEL_NONE;
        int rc = 0;

        path = build_path_from_dentry(dentry, page);
        if (IS_ERR(path)) {
                rc = PTR_ERR(path);
                goto notify_exit;
        }

        utf16_path = cifs_convert_path_to_utf16(path, cifs_sb);
        if (utf16_path == NULL) {
                rc = -ENOMEM;
                goto notify_exit;
        }

        if (copy_from_user(&notify, ioc_buf, sizeof(struct smb3_notify))) {
                rc = -EFAULT;
                goto notify_exit;
        }

        tcon = cifs_sb_master_tcon(cifs_sb);
        oparms.tcon = tcon;
        oparms.desired_access = FILE_READ_ATTRIBUTES | FILE_READ_DATA;
        oparms.disposition = FILE_OPEN;
        oparms.create_options = cifs_create_options(cifs_sb, 0);
        oparms.fid = &fid;
        oparms.reconnect = false;

        rc = SMB2_open(xid, &oparms, utf16_path, &oplock, NULL, NULL, NULL,
                       NULL);
        if (rc)
                goto notify_exit;

        rc = SMB2_change_notify(xid, tcon, fid.persistent_fid, fid.volatile_fid,
                                notify.watch_tree, notify.completion_filter);

        SMB2_close(xid, tcon, fid.persistent_fid, fid.volatile_fid);

        cifs_dbg(FYI, "change notify for path %s rc %d\n", path, rc);

notify_exit:
        free_dentry_path(page);
        kfree(utf16_path);
        return rc;
}

static int
smb2_query_dir_first(const unsigned int xid, struct cifs_tcon *tcon,
                     const char *path, struct cifs_sb_info *cifs_sb,
                     struct cifs_fid *fid, __u16 search_flags,
                     struct cifs_search_info *srch_inf)
{
        __le16 *utf16_path;
        struct smb_rqst rqst[2];
        struct kvec rsp_iov[2];
        int resp_buftype[2];
        struct kvec open_iov[SMB2_CREATE_IOV_SIZE];
        struct kvec qd_iov[SMB2_QUERY_DIRECTORY_IOV_SIZE];
        int rc, flags = 0;
        u8 oplock = SMB2_OPLOCK_LEVEL_NONE;
        struct cifs_open_parms oparms;
        struct smb2_query_directory_rsp *qd_rsp = NULL;
        struct smb2_create_rsp *op_rsp = NULL;
        struct TCP_Server_Info *server = cifs_pick_channel(tcon->ses);
        int retry_count = 0;

        utf16_path = cifs_convert_path_to_utf16(path, cifs_sb);
        if (!utf16_path)
                return -ENOMEM;

        if (smb3_encryption_required(tcon))
                flags |= CIFS_TRANSFORM_REQ;

        memset(rqst, 0, sizeof(rqst));
        resp_buftype[0] = resp_buftype[1] = CIFS_NO_BUFFER;
        memset(rsp_iov, 0, sizeof(rsp_iov));

        /* Open */
        memset(&open_iov, 0, sizeof(open_iov));
        rqst[0].rq_iov = open_iov;
        rqst[0].rq_nvec = SMB2_CREATE_IOV_SIZE;

        oparms.tcon = tcon;
        oparms.desired_access = FILE_READ_ATTRIBUTES | FILE_READ_DATA;
        oparms.disposition = FILE_OPEN;
        oparms.create_options = cifs_create_options(cifs_sb, 0);
        oparms.fid = fid;
        oparms.reconnect = false;

        rc = SMB2_open_init(tcon, server,
                            &rqst[0], &oplock, &oparms, utf16_path);
        if (rc)
                goto qdf_free;
        smb2_set_next_command(tcon, &rqst[0]);

        /* Query directory */
        srch_inf->entries_in_buffer = 0;
        srch_inf->index_of_last_entry = 2;

        memset(&qd_iov, 0, sizeof(qd_iov));
        rqst[1].rq_iov = qd_iov;
        rqst[1].rq_nvec = SMB2_QUERY_DIRECTORY_IOV_SIZE;

        rc = SMB2_query_directory_init(xid, tcon, server,
                                       &rqst[1],
                                       COMPOUND_FID, COMPOUND_FID,
                                       0, srch_inf->info_level);
        if (rc)
                goto qdf_free;

        smb2_set_related(&rqst[1]);

again:
        rc = compound_send_recv(xid, tcon->ses, server,
                                flags, 2, rqst,
                                resp_buftype, rsp_iov);

        if (rc == -EAGAIN && retry_count++ < 10)
                goto again;

        /* If the open failed there is nothing to do */
        op_rsp = (struct smb2_create_rsp *)rsp_iov[0].iov_base;
        if (op_rsp == NULL || op_rsp->hdr.Status != STATUS_SUCCESS) {
                cifs_dbg(FYI, "query_dir_first: open failed rc=%d\n", rc);
                goto qdf_free;
        }
        fid->persistent_fid = op_rsp->PersistentFileId;
        fid->volatile_fid = op_rsp->VolatileFileId;

        /* Anything else than ENODATA means a genuine error */
        if (rc && rc != -ENODATA) {
                SMB2_close(xid, tcon, fid->persistent_fid, fid->volatile_fid);
                cifs_dbg(FYI, "query_dir_first: query directory failed rc=%d\n", rc);
                trace_smb3_query_dir_err(xid, fid->persistent_fid,
                                         tcon->tid, tcon->ses->Suid, 0, 0, rc);
                goto qdf_free;
        }

        atomic_inc(&tcon->num_remote_opens);

        qd_rsp = (struct smb2_query_directory_rsp *)rsp_iov[1].iov_base;
        if (qd_rsp->hdr.Status == STATUS_NO_MORE_FILES) {
                trace_smb3_query_dir_done(xid, fid->persistent_fid,
                                          tcon->tid, tcon->ses->Suid, 0, 0);
                srch_inf->endOfSearch = true;
                rc = 0;
                goto qdf_free;
        }

        rc = smb2_parse_query_directory(tcon, &rsp_iov[1], resp_buftype[1],
                                        srch_inf);
        if (rc) {
                trace_smb3_query_dir_err(xid, fid->persistent_fid, tcon->tid,
                        tcon->ses->Suid, 0, 0, rc);
                goto qdf_free;
        }
        resp_buftype[1] = CIFS_NO_BUFFER;

        trace_smb3_query_dir_done(xid, fid->persistent_fid, tcon->tid,
                        tcon->ses->Suid, 0, srch_inf->entries_in_buffer);

 qdf_free:
        kfree(utf16_path);
        SMB2_open_free(&rqst[0]);
        SMB2_query_directory_free(&rqst[1]);
        free_rsp_buf(resp_buftype[0], rsp_iov[0].iov_base);
        free_rsp_buf(resp_buftype[1], rsp_iov[1].iov_base);
        return rc;
}

static int
smb2_query_dir_next(const unsigned int xid, struct cifs_tcon *tcon,
                    struct cifs_fid *fid, __u16 search_flags,
                    struct cifs_search_info *srch_inf)
{
        return SMB2_query_directory(xid, tcon, fid->persistent_fid,
                                    fid->volatile_fid, 0, srch_inf);
}

static int
smb2_close_dir(const unsigned int xid, struct cifs_tcon *tcon,
               struct cifs_fid *fid)
{
        return SMB2_close(xid, tcon, fid->persistent_fid, fid->volatile_fid);
}

/*
 * If we negotiate SMB2 protocol and get STATUS_PENDING - update
 * the number of credits and return true. Otherwise - return false.
 */
static bool
smb2_is_status_pending(char *buf, struct TCP_Server_Info *server)
{
        struct smb2_hdr *shdr = (struct smb2_hdr *)buf;
        int scredits, in_flight;

        if (shdr->Status != STATUS_PENDING)
                return false;

        if (shdr->CreditRequest) {
                spin_lock(&server->req_lock);
                server->credits += le16_to_cpu(shdr->CreditRequest);
                scredits = server->credits;
                in_flight = server->in_flight;
                spin_unlock(&server->req_lock);
                wake_up(&server->request_q);

                trace_smb3_pend_credits(server->CurrentMid,
                                server->conn_id, server->hostname, scredits,
                                le16_to_cpu(shdr->CreditRequest), in_flight);
                cifs_dbg(FYI, "%s: status pending add %u credits total=%d\n",
                                __func__, le16_to_cpu(shdr->CreditRequest), scredits);
        }

        return true;
}

static bool
smb2_is_session_expired(char *buf)
{
        struct smb2_hdr *shdr = (struct smb2_hdr *)buf;

        if (shdr->Status != STATUS_NETWORK_SESSION_EXPIRED &&
            shdr->Status != STATUS_USER_SESSION_DELETED)
                return false;

        trace_smb3_ses_expired(le32_to_cpu(shdr->Id.SyncId.TreeId),
                               le64_to_cpu(shdr->SessionId),
                               le16_to_cpu(shdr->Command),
                               le64_to_cpu(shdr->MessageId));
        cifs_dbg(FYI, "Session expired or deleted\n");

        return true;
}

static bool
smb2_is_status_io_timeout(char *buf)
{
        struct smb2_hdr *shdr = (struct smb2_hdr *)buf;

        if (shdr->Status == STATUS_IO_TIMEOUT)
                return true;
        else
                return false;
}

static void
smb2_is_network_name_deleted(char *buf, struct TCP_Server_Info *server)
{
        struct smb2_hdr *shdr = (struct smb2_hdr *)buf;
        struct cifs_ses *ses;
        struct cifs_tcon *tcon;

        if (shdr->Status != STATUS_NETWORK_NAME_DELETED)
                return;

        spin_lock(&cifs_tcp_ses_lock);
        list_for_each_entry(ses, &server->smb_ses_list, smb_ses_list) {
                list_for_each_entry(tcon, &ses->tcon_list, tcon_list) {
                        if (tcon->tid == le32_to_cpu(shdr->Id.SyncId.TreeId)) {
                                spin_lock(&tcon->tc_lock);
                                tcon->need_reconnect = true;
                                spin_unlock(&tcon->tc_lock);
                                spin_unlock(&cifs_tcp_ses_lock);
                                pr_warn_once("Server share %s deleted.\n",
                                             tcon->treeName);
                                return;
                        }
                }
        }
        spin_unlock(&cifs_tcp_ses_lock);
}

static int
smb2_oplock_response(struct cifs_tcon *tcon, struct cifs_fid *fid,
                     struct cifsInodeInfo *cinode)
{
        if (tcon->ses->server->capabilities & SMB2_GLOBAL_CAP_LEASING)
                return SMB2_lease_break(0, tcon, cinode->lease_key,
                                        smb2_get_lease_state(cinode));

        return SMB2_oplock_break(0, tcon, fid->persistent_fid,
                                 fid->volatile_fid,
                                 CIFS_CACHE_READ(cinode) ? 1 : 0);
}

void
smb2_set_related(struct smb_rqst *rqst)
{
        struct smb2_hdr *shdr;

        shdr = (struct smb2_hdr *)(rqst->rq_iov[0].iov_base);
        if (shdr == NULL) {
                cifs_dbg(FYI, "shdr NULL in smb2_set_related\n");
                return;
        }
        shdr->Flags |= SMB2_FLAGS_RELATED_OPERATIONS;
}

char smb2_padding[7] = {0, 0, 0, 0, 0, 0, 0};

void
smb2_set_next_command(struct cifs_tcon *tcon, struct smb_rqst *rqst)
{
        struct smb2_hdr *shdr;
        struct cifs_ses *ses = tcon->ses;
        struct TCP_Server_Info *server = ses->server;
        unsigned long len = smb_rqst_len(server, rqst);
        int i, num_padding;

        shdr = (struct smb2_hdr *)(rqst->rq_iov[0].iov_base);
        if (shdr == NULL) {
                cifs_dbg(FYI, "shdr NULL in smb2_set_next_command\n");
                return;
        }

        /* SMB headers in a compound are 8 byte aligned. */

        /* No padding needed */
        if (!(len & 7))
                goto finished;

        num_padding = 8 - (len & 7);
        if (!smb3_encryption_required(tcon)) {
                /*
                 * If we do not have encryption then we can just add an extra
                 * iov for the padding.
                 */
                rqst->rq_iov[rqst->rq_nvec].iov_base = smb2_padding;
                rqst->rq_iov[rqst->rq_nvec].iov_len = num_padding;
                rqst->rq_nvec++;
                len += num_padding;
        } else {
                /*
                 * We can not add a small padding iov for the encryption case
                 * because the encryption framework can not handle the padding
                 * iovs.
                 * We have to flatten this into a single buffer and add
                 * the padding to it.
                 */
                for (i = 1; i < rqst->rq_nvec; i++) {
                        memcpy(rqst->rq_iov[0].iov_base +
                               rqst->rq_iov[0].iov_len,
                               rqst->rq_iov[i].iov_base,
                               rqst->rq_iov[i].iov_len);
                        rqst->rq_iov[0].iov_len += rqst->rq_iov[i].iov_len;
                }
                memset(rqst->rq_iov[0].iov_base + rqst->rq_iov[0].iov_len,
                       0, num_padding);
                rqst->rq_iov[0].iov_len += num_padding;
                len += num_padding;
                rqst->rq_nvec = 1;
        }

 finished:
        shdr->NextCommand = cpu_to_le32(len);
}

/*
 * Passes the query info response back to the caller on success.
 * Caller need to free this with free_rsp_buf().
 */
int
smb2_query_info_compound(const unsigned int xid, struct cifs_tcon *tcon,
                         const char *path, u32 desired_access,
                         u32 class, u32 type, u32 output_len,
                         struct kvec *rsp, int *buftype,
                         struct cifs_sb_info *cifs_sb)
{
        struct cifs_ses *ses = tcon->ses;
        struct TCP_Server_Info *server = cifs_pick_channel(ses);
        int flags = CIFS_CP_CREATE_CLOSE_OP;
        struct smb_rqst rqst[3];
        int resp_buftype[3];
        struct kvec rsp_iov[3];
        struct kvec open_iov[SMB2_CREATE_IOV_SIZE];
        struct kvec qi_iov[1];
        struct kvec close_iov[1];
        u8 oplock = SMB2_OPLOCK_LEVEL_NONE;
        struct cifs_open_parms oparms;
        struct cifs_fid fid;
        int rc;
        __le16 *utf16_path;
        struct cached_fid *cfid = NULL;

        if (!path)
                path = "";
        utf16_path = cifs_convert_path_to_utf16(path, cifs_sb);
        if (!utf16_path)
                return -ENOMEM;

        if (smb3_encryption_required(tcon))
                flags |= CIFS_TRANSFORM_REQ;

        memset(rqst, 0, sizeof(rqst));
        resp_buftype[0] = resp_buftype[1] = resp_buftype[2] = CIFS_NO_BUFFER;
        memset(rsp_iov, 0, sizeof(rsp_iov));

        /*
         * We can only call this for things we know are directories.
         */
        if (!strcmp(path, ""))
                open_cached_dir(xid, tcon, path, cifs_sb, false,
                                &cfid); /* cfid null if open dir failed */

        memset(&open_iov, 0, sizeof(open_iov));
        rqst[0].rq_iov = open_iov;
        rqst[0].rq_nvec = SMB2_CREATE_IOV_SIZE;

        oparms.tcon = tcon;
        oparms.desired_access = desired_access;
        oparms.disposition = FILE_OPEN;
        oparms.create_options = cifs_create_options(cifs_sb, 0);
        oparms.fid = &fid;
        oparms.reconnect = false;

        rc = SMB2_open_init(tcon, server,
                            &rqst[0], &oplock, &oparms, utf16_path);
        if (rc)
                goto qic_exit;
        smb2_set_next_command(tcon, &rqst[0]);

        memset(&qi_iov, 0, sizeof(qi_iov));
        rqst[1].rq_iov = qi_iov;
        rqst[1].rq_nvec = 1;

        if (cfid) {
                rc = SMB2_query_info_init(tcon, server,
                                          &rqst[1],
                                          cfid->fid.persistent_fid,
                                          cfid->fid.volatile_fid,
                                          class, type, 0,
                                          output_len, 0,
                                          NULL);
        } else {
                rc = SMB2_query_info_init(tcon, server,
                                          &rqst[1],
                                          COMPOUND_FID,
                                          COMPOUND_FID,
                                          class, type, 0,
                                          output_len, 0,
                                          NULL);
        }
        if (rc)
                goto qic_exit;
        if (!cfid) {
                smb2_set_next_command(tcon, &rqst[1]);
                smb2_set_related(&rqst[1]);
        }

        memset(&close_iov, 0, sizeof(close_iov));
        rqst[2].rq_iov = close_iov;
        rqst[2].rq_nvec = 1;

        rc = SMB2_close_init(tcon, server,
                             &rqst[2], COMPOUND_FID, COMPOUND_FID, false);
        if (rc)
                goto qic_exit;
        smb2_set_related(&rqst[2]);

        if (cfid) {
                rc = compound_send_recv(xid, ses, server,
                                        flags, 1, &rqst[1],
                                        &resp_buftype[1], &rsp_iov[1]);
        } else {
                rc = compound_send_recv(xid, ses, server,
                                        flags, 3, rqst,
                                        resp_buftype, rsp_iov);
        }
        if (rc) {
                free_rsp_buf(resp_buftype[1], rsp_iov[1].iov_base);
                if (rc == -EREMCHG) {
                        tcon->need_reconnect = true;
                        pr_warn_once("server share %s deleted\n",
                                     tcon->treeName);
                }
                goto qic_exit;
        }
        *rsp = rsp_iov[1];
        *buftype = resp_buftype[1];

 qic_exit:
        kfree(utf16_path);
        SMB2_open_free(&rqst[0]);
        SMB2_query_info_free(&rqst[1]);
        SMB2_close_free(&rqst[2]);
        free_rsp_buf(resp_buftype[0], rsp_iov[0].iov_base);
        free_rsp_buf(resp_buftype[2], rsp_iov[2].iov_base);
        if (cfid)
                close_cached_dir(cfid);
        return rc;
}

static int
smb2_queryfs(const unsigned int xid, struct cifs_tcon *tcon,
             struct cifs_sb_info *cifs_sb, struct kstatfs *buf)
{
        struct smb2_query_info_rsp *rsp;
        struct smb2_fs_full_size_info *info = NULL;
        struct kvec rsp_iov = {NULL, 0};
        int buftype = CIFS_NO_BUFFER;
        int rc;


        rc = smb2_query_info_compound(xid, tcon, "",
                                      FILE_READ_ATTRIBUTES,
                                      FS_FULL_SIZE_INFORMATION,
                                      SMB2_O_INFO_FILESYSTEM,
                                      sizeof(struct smb2_fs_full_size_info),
                                      &rsp_iov, &buftype, cifs_sb);
        if (rc)
                goto qfs_exit;

        rsp = (struct smb2_query_info_rsp *)rsp_iov.iov_base;
        buf->f_type = SMB2_SUPER_MAGIC;
        info = (struct smb2_fs_full_size_info *)(
                le16_to_cpu(rsp->OutputBufferOffset) + (char *)rsp);
        rc = smb2_validate_iov(le16_to_cpu(rsp->OutputBufferOffset),
                               le32_to_cpu(rsp->OutputBufferLength),
                               &rsp_iov,
                               sizeof(struct smb2_fs_full_size_info));
        if (!rc)
                smb2_copy_fs_info_to_kstatfs(info, buf);

qfs_exit:
        free_rsp_buf(buftype, rsp_iov.iov_base);
        return rc;
}

static int
smb311_queryfs(const unsigned int xid, struct cifs_tcon *tcon,
               struct cifs_sb_info *cifs_sb, struct kstatfs *buf)
{
        int rc;
        __le16 srch_path = 0; /* Null - open root of share */
        u8 oplock = SMB2_OPLOCK_LEVEL_NONE;
        struct cifs_open_parms oparms;
        struct cifs_fid fid;

        if (!tcon->posix_extensions)
                return smb2_queryfs(xid, tcon, cifs_sb, buf);

        oparms.tcon = tcon;
        oparms.desired_access = FILE_READ_ATTRIBUTES;
        oparms.disposition = FILE_OPEN;
        oparms.create_options = cifs_create_options(cifs_sb, 0);
        oparms.fid = &fid;
        oparms.reconnect = false;

        rc = SMB2_open(xid, &oparms, &srch_path, &oplock, NULL, NULL,
                       NULL, NULL);
        if (rc)
                return rc;

        rc = SMB311_posix_qfs_info(xid, tcon, fid.persistent_fid,
                                   fid.volatile_fid, buf);
        buf->f_type = SMB2_SUPER_MAGIC;
        SMB2_close(xid, tcon, fid.persistent_fid, fid.volatile_fid);
        return rc;
}

static bool
smb2_compare_fids(struct cifsFileInfo *ob1, struct cifsFileInfo *ob2)
{
        return ob1->fid.persistent_fid == ob2->fid.persistent_fid &&
               ob1->fid.volatile_fid == ob2->fid.volatile_fid;
}

static int
smb2_mand_lock(const unsigned int xid, struct cifsFileInfo *cfile, __u64 offset,
               __u64 length, __u32 type, int lock, int unlock, bool wait)
{
        if (unlock && !lock)
                type = SMB2_LOCKFLAG_UNLOCK;
        return SMB2_lock(xid, tlink_tcon(cfile->tlink),
                         cfile->fid.persistent_fid, cfile->fid.volatile_fid,
                         current->tgid, length, offset, type, wait);
}

static void
smb2_get_lease_key(struct inode *inode, struct cifs_fid *fid)
{
        memcpy(fid->lease_key, CIFS_I(inode)->lease_key, SMB2_LEASE_KEY_SIZE);
}

static void
smb2_set_lease_key(struct inode *inode, struct cifs_fid *fid)
{
        memcpy(CIFS_I(inode)->lease_key, fid->lease_key, SMB2_LEASE_KEY_SIZE);
}

static void
smb2_new_lease_key(struct cifs_fid *fid)
{
        generate_random_uuid(fid->lease_key);
}

static int
smb2_get_dfs_refer(const unsigned int xid, struct cifs_ses *ses,
                   const char *search_name,
                   struct dfs_info3_param **target_nodes,
                   unsigned int *num_of_nodes,
                   const struct nls_table *nls_codepage, int remap)
{
        int rc;
        __le16 *utf16_path = NULL;
        int utf16_path_len = 0;
        struct cifs_tcon *tcon;
        struct fsctl_get_dfs_referral_req *dfs_req = NULL;
        struct get_dfs_referral_rsp *dfs_rsp = NULL;
        u32 dfs_req_size = 0, dfs_rsp_size = 0;
        int retry_count = 0;

        cifs_dbg(FYI, "%s: path: %s\n", __func__, search_name);

        /*
         * Try to use the IPC tcon, otherwise just use any
         */
        tcon = ses->tcon_ipc;
        if (tcon == NULL) {
                spin_lock(&cifs_tcp_ses_lock);
                tcon = list_first_entry_or_null(&ses->tcon_list,
                                                struct cifs_tcon,
                                                tcon_list);
                if (tcon)
                        tcon->tc_count++;
                spin_unlock(&cifs_tcp_ses_lock);
        }

        if (tcon == NULL) {
                cifs_dbg(VFS, "session %p has no tcon available for a dfs referral request\n",
                         ses);
                rc = -ENOTCONN;
                goto out;
        }

        utf16_path = cifs_strndup_to_utf16(search_name, PATH_MAX,
                                           &utf16_path_len,
                                           nls_codepage, remap);
        if (!utf16_path) {
                rc = -ENOMEM;
                goto out;
        }

        dfs_req_size = sizeof(*dfs_req) + utf16_path_len;
        dfs_req = kzalloc(dfs_req_size, GFP_KERNEL);
        if (!dfs_req) {
                rc = -ENOMEM;
                goto out;
        }

        /* Highest DFS referral version understood */
        dfs_req->MaxReferralLevel = DFS_VERSION;

        /* Path to resolve in an UTF-16 null-terminated string */
        memcpy(dfs_req->RequestFileName, utf16_path, utf16_path_len);

        do {
                rc = SMB2_ioctl(xid, tcon, NO_FILE_ID, NO_FILE_ID,
                                FSCTL_DFS_GET_REFERRALS,
                                (char *)dfs_req, dfs_req_size, CIFSMaxBufSize,
                                (char **)&dfs_rsp, &dfs_rsp_size);
                if (!is_retryable_error(rc))
                        break;
                usleep_range(512, 2048);
        } while (++retry_count < 5);

        if (rc) {
                if (!is_retryable_error(rc) && rc != -ENOENT && rc != -EOPNOTSUPP)
                        cifs_tcon_dbg(VFS, "%s: ioctl error: rc=%d\n", __func__, rc);
                goto out;
        }

        rc = parse_dfs_referrals(dfs_rsp, dfs_rsp_size,
                                 num_of_nodes, target_nodes,
                                 nls_codepage, remap, search_name,
                                 true /* is_unicode */);
        if (rc) {
                cifs_tcon_dbg(VFS, "parse error in %s rc=%d\n", __func__, rc);
                goto out;
        }

 out:
        if (tcon && !tcon->ipc) {
                /* ipc tcons are not refcounted */
                spin_lock(&cifs_tcp_ses_lock);
                tcon->tc_count--;
                /* tc_count can never go negative */
                WARN_ON(tcon->tc_count < 0);
                spin_unlock(&cifs_tcp_ses_lock);
        }
        kfree(utf16_path);
        kfree(dfs_req);
        kfree(dfs_rsp);
        return rc;
}

static int
parse_reparse_posix(struct reparse_posix_data *symlink_buf,
                      u32 plen, char **target_path,
                      struct cifs_sb_info *cifs_sb)
{
        unsigned int len;

        /* See MS-FSCC 2.1.2.6 for the 'NFS' style reparse tags */
        len = le16_to_cpu(symlink_buf->ReparseDataLength);

        if (le64_to_cpu(symlink_buf->InodeType) != NFS_SPECFILE_LNK) {
                cifs_dbg(VFS, "%lld not a supported symlink type\n",
                        le64_to_cpu(symlink_buf->InodeType));
                return -EOPNOTSUPP;
        }

        *target_path = cifs_strndup_from_utf16(
                                symlink_buf->PathBuffer,
                                len, true, cifs_sb->local_nls);
        if (!(*target_path))
                return -ENOMEM;

        convert_delimiter(*target_path, '/');
        cifs_dbg(FYI, "%s: target path: %s\n", __func__, *target_path);

        return 0;
}

static int
parse_reparse_symlink(struct reparse_symlink_data_buffer *symlink_buf,
                      u32 plen, char **target_path,
                      struct cifs_sb_info *cifs_sb)
{
        unsigned int sub_len;
        unsigned int sub_offset;

        /* We handle Symbolic Link reparse tag here. See: MS-FSCC 2.1.2.4 */

        sub_offset = le16_to_cpu(symlink_buf->SubstituteNameOffset);
        sub_len = le16_to_cpu(symlink_buf->SubstituteNameLength);
        if (sub_offset + 20 > plen ||
            sub_offset + sub_len + 20 > plen) {
                cifs_dbg(VFS, "srv returned malformed symlink buffer\n");
                return -EIO;
        }

        *target_path = cifs_strndup_from_utf16(
                                symlink_buf->PathBuffer + sub_offset,
                                sub_len, true, cifs_sb->local_nls);
        if (!(*target_path))
                return -ENOMEM;

        convert_delimiter(*target_path, '/');
        cifs_dbg(FYI, "%s: target path: %s\n", __func__, *target_path);

        return 0;
}

static int
parse_reparse_point(struct reparse_data_buffer *buf,
                    u32 plen, char **target_path,
                    struct cifs_sb_info *cifs_sb)
{
        if (plen < sizeof(struct reparse_data_buffer)) {
                cifs_dbg(VFS, "reparse buffer is too small. Must be at least 8 bytes but was %d\n",
                         plen);
                return -EIO;
        }

        if (plen < le16_to_cpu(buf->ReparseDataLength) +
            sizeof(struct reparse_data_buffer)) {
                cifs_dbg(VFS, "srv returned invalid reparse buf length: %d\n",
                         plen);
                return -EIO;
        }

        /* See MS-FSCC 2.1.2 */
        switch (le32_to_cpu(buf->ReparseTag)) {
        case IO_REPARSE_TAG_NFS:
                return parse_reparse_posix(
                        (struct reparse_posix_data *)buf,
                        plen, target_path, cifs_sb);
        case IO_REPARSE_TAG_SYMLINK:
                return parse_reparse_symlink(
                        (struct reparse_symlink_data_buffer *)buf,
                        plen, target_path, cifs_sb);
        default:
                cifs_dbg(VFS, "srv returned unknown symlink buffer tag:0x%08x\n",
                         le32_to_cpu(buf->ReparseTag));
                return -EOPNOTSUPP;
        }
}

#define SMB2_SYMLINK_STRUCT_SIZE \
        (sizeof(struct smb2_err_rsp) - 1 + sizeof(struct smb2_symlink_err_rsp))

static int
smb2_query_symlink(const unsigned int xid, struct cifs_tcon *tcon,
                   struct cifs_sb_info *cifs_sb, const char *full_path,
                   char **target_path, bool is_reparse_point)
{
        int rc;
        __le16 *utf16_path = NULL;
        __u8 oplock = SMB2_OPLOCK_LEVEL_NONE;
        struct cifs_open_parms oparms;
        struct cifs_fid fid;
        struct kvec err_iov = {NULL, 0};
        struct smb2_err_rsp *err_buf = NULL;
        struct smb2_symlink_err_rsp *symlink;
        struct TCP_Server_Info *server = cifs_pick_channel(tcon->ses);
        unsigned int sub_len;
        unsigned int sub_offset;
        unsigned int print_len;
        unsigned int print_offset;
        int flags = CIFS_CP_CREATE_CLOSE_OP;
        struct smb_rqst rqst[3];
        int resp_buftype[3];
        struct kvec rsp_iov[3];
        struct kvec open_iov[SMB2_CREATE_IOV_SIZE];
        struct kvec io_iov[SMB2_IOCTL_IOV_SIZE];
        struct kvec close_iov[1];
        struct smb2_create_rsp *create_rsp;
        struct smb2_ioctl_rsp *ioctl_rsp;
        struct reparse_data_buffer *reparse_buf;
        int create_options = is_reparse_point ? OPEN_REPARSE_POINT : 0;
        u32 plen;

        cifs_dbg(FYI, "%s: path: %s\n", __func__, full_path);

        *target_path = NULL;

        if (smb3_encryption_required(tcon))
                flags |= CIFS_TRANSFORM_REQ;

        memset(rqst, 0, sizeof(rqst));
        resp_buftype[0] = resp_buftype[1] = resp_buftype[2] = CIFS_NO_BUFFER;
        memset(rsp_iov, 0, sizeof(rsp_iov));

        utf16_path = cifs_convert_path_to_utf16(full_path, cifs_sb);
        if (!utf16_path)
                return -ENOMEM;

        /* Open */
        memset(&open_iov, 0, sizeof(open_iov));
        rqst[0].rq_iov = open_iov;
        rqst[0].rq_nvec = SMB2_CREATE_IOV_SIZE;

        memset(&oparms, 0, sizeof(oparms));
        oparms.tcon = tcon;
        oparms.desired_access = FILE_READ_ATTRIBUTES;
        oparms.disposition = FILE_OPEN;
        oparms.create_options = cifs_create_options(cifs_sb, create_options);
        oparms.fid = &fid;
        oparms.reconnect = false;

        rc = SMB2_open_init(tcon, server,
                            &rqst[0], &oplock, &oparms, utf16_path);
        if (rc)
                goto querty_exit;
        smb2_set_next_command(tcon, &rqst[0]);


        /* IOCTL */
        memset(&io_iov, 0, sizeof(io_iov));
        rqst[1].rq_iov = io_iov;
        rqst[1].rq_nvec = SMB2_IOCTL_IOV_SIZE;

        rc = SMB2_ioctl_init(tcon, server,
                             &rqst[1], fid.persistent_fid,
                             fid.volatile_fid, FSCTL_GET_REPARSE_POINT, NULL, 0,
                             CIFSMaxBufSize -
                             MAX_SMB2_CREATE_RESPONSE_SIZE -
                             MAX_SMB2_CLOSE_RESPONSE_SIZE);
        if (rc)
                goto querty_exit;

        smb2_set_next_command(tcon, &rqst[1]);
        smb2_set_related(&rqst[1]);


        /* Close */
        memset(&close_iov, 0, sizeof(close_iov));
        rqst[2].rq_iov = close_iov;
        rqst[2].rq_nvec = 1;

        rc = SMB2_close_init(tcon, server,
                             &rqst[2], COMPOUND_FID, COMPOUND_FID, false);
        if (rc)
                goto querty_exit;

        smb2_set_related(&rqst[2]);

        rc = compound_send_recv(xid, tcon->ses, server,
                                flags, 3, rqst,
                                resp_buftype, rsp_iov);

        create_rsp = rsp_iov[0].iov_base;
        if (create_rsp && create_rsp->hdr.Status)
                err_iov = rsp_iov[0];
        ioctl_rsp = rsp_iov[1].iov_base;

        /*
         * Open was successful and we got an ioctl response.
         */
        if ((rc == 0) && (is_reparse_point)) {
                /* See MS-FSCC 2.3.23 */

                reparse_buf = (struct reparse_data_buffer *)
                        ((char *)ioctl_rsp +
                         le32_to_cpu(ioctl_rsp->OutputOffset));
                plen = le32_to_cpu(ioctl_rsp->OutputCount);

                if (plen + le32_to_cpu(ioctl_rsp->OutputOffset) >
                    rsp_iov[1].iov_len) {
                        cifs_tcon_dbg(VFS, "srv returned invalid ioctl len: %d\n",
                                 plen);
                        rc = -EIO;
                        goto querty_exit;
                }

                rc = parse_reparse_point(reparse_buf, plen, target_path,
                                         cifs_sb);
                goto querty_exit;
        }

        if (!rc || !err_iov.iov_base) {
                rc = -ENOENT;
                goto querty_exit;
        }

        err_buf = err_iov.iov_base;
        if (le32_to_cpu(err_buf->ByteCount) < sizeof(struct smb2_symlink_err_rsp) ||
            err_iov.iov_len < SMB2_SYMLINK_STRUCT_SIZE) {
                rc = -EINVAL;
                goto querty_exit;
        }

        symlink = (struct smb2_symlink_err_rsp *)err_buf->ErrorData;
        if (le32_to_cpu(symlink->SymLinkErrorTag) != SYMLINK_ERROR_TAG ||
            le32_to_cpu(symlink->ReparseTag) != IO_REPARSE_TAG_SYMLINK) {
                rc = -EINVAL;
                goto querty_exit;
        }

        /* open must fail on symlink - reset rc */
        rc = 0;
        sub_len = le16_to_cpu(symlink->SubstituteNameLength);
        sub_offset = le16_to_cpu(symlink->SubstituteNameOffset);
        print_len = le16_to_cpu(symlink->PrintNameLength);
        print_offset = le16_to_cpu(symlink->PrintNameOffset);

        if (err_iov.iov_len < SMB2_SYMLINK_STRUCT_SIZE + sub_offset + sub_len) {
                rc = -EINVAL;
                goto querty_exit;
        }

        if (err_iov.iov_len <
            SMB2_SYMLINK_STRUCT_SIZE + print_offset + print_len) {
                rc = -EINVAL;
                goto querty_exit;
        }

        *target_path = cifs_strndup_from_utf16(
                                (char *)symlink->PathBuffer + sub_offset,
                                sub_len, true, cifs_sb->local_nls);
        if (!(*target_path)) {
                rc = -ENOMEM;
                goto querty_exit;
        }
        convert_delimiter(*target_path, '/');
        cifs_dbg(FYI, "%s: target path: %s\n", __func__, *target_path);

 querty_exit:
        cifs_dbg(FYI, "query symlink rc %d\n", rc);
        kfree(utf16_path);
        SMB2_open_free(&rqst[0]);
        SMB2_ioctl_free(&rqst[1]);
        SMB2_close_free(&rqst[2]);
        free_rsp_buf(resp_buftype[0], rsp_iov[0].iov_base);
        free_rsp_buf(resp_buftype[1], rsp_iov[1].iov_base);
        free_rsp_buf(resp_buftype[2], rsp_iov[2].iov_base);
        return rc;
}

int
smb2_query_reparse_tag(const unsigned int xid, struct cifs_tcon *tcon,
                   struct cifs_sb_info *cifs_sb, const char *full_path,
                   __u32 *tag)
{
        int rc;
        __le16 *utf16_path = NULL;
        __u8 oplock = SMB2_OPLOCK_LEVEL_NONE;
        struct cifs_open_parms oparms;
        struct cifs_fid fid;
        struct TCP_Server_Info *server = cifs_pick_channel(tcon->ses);
        int flags = CIFS_CP_CREATE_CLOSE_OP;
        struct smb_rqst rqst[3];
        int resp_buftype[3];
        struct kvec rsp_iov[3];
        struct kvec open_iov[SMB2_CREATE_IOV_SIZE];
        struct kvec io_iov[SMB2_IOCTL_IOV_SIZE];
        struct kvec close_iov[1];
        struct smb2_ioctl_rsp *ioctl_rsp;
        struct reparse_data_buffer *reparse_buf;
        u32 plen;

        cifs_dbg(FYI, "%s: path: %s\n", __func__, full_path);

        if (smb3_encryption_required(tcon))
                flags |= CIFS_TRANSFORM_REQ;

        memset(rqst, 0, sizeof(rqst));
        resp_buftype[0] = resp_buftype[1] = resp_buftype[2] = CIFS_NO_BUFFER;
        memset(rsp_iov, 0, sizeof(rsp_iov));

        utf16_path = cifs_convert_path_to_utf16(full_path, cifs_sb);
        if (!utf16_path)
                return -ENOMEM;

        /*
         * setup smb2open - TODO add optimization to call cifs_get_readable_path
         * to see if there is a handle already open that we can use
         */
        memset(&open_iov, 0, sizeof(open_iov));
        rqst[0].rq_iov = open_iov;
        rqst[0].rq_nvec = SMB2_CREATE_IOV_SIZE;

        memset(&oparms, 0, sizeof(oparms));
        oparms.tcon = tcon;
        oparms.desired_access = FILE_READ_ATTRIBUTES;
        oparms.disposition = FILE_OPEN;
        oparms.create_options = cifs_create_options(cifs_sb, OPEN_REPARSE_POINT);
        oparms.fid = &fid;
        oparms.reconnect = false;

        rc = SMB2_open_init(tcon, server,
                            &rqst[0], &oplock, &oparms, utf16_path);
        if (rc)
                goto query_rp_exit;
        smb2_set_next_command(tcon, &rqst[0]);


        /* IOCTL */
        memset(&io_iov, 0, sizeof(io_iov));
        rqst[1].rq_iov = io_iov;
        rqst[1].rq_nvec = SMB2_IOCTL_IOV_SIZE;

        rc = SMB2_ioctl_init(tcon, server,
                             &rqst[1], COMPOUND_FID,
                             COMPOUND_FID, FSCTL_GET_REPARSE_POINT, NULL, 0,
                             CIFSMaxBufSize -
                             MAX_SMB2_CREATE_RESPONSE_SIZE -
                             MAX_SMB2_CLOSE_RESPONSE_SIZE);
        if (rc)
                goto query_rp_exit;

        smb2_set_next_command(tcon, &rqst[1]);
        smb2_set_related(&rqst[1]);


        /* Close */
        memset(&close_iov, 0, sizeof(close_iov));
        rqst[2].rq_iov = close_iov;
        rqst[2].rq_nvec = 1;

        rc = SMB2_close_init(tcon, server,
                             &rqst[2], COMPOUND_FID, COMPOUND_FID, false);
        if (rc)
                goto query_rp_exit;

        smb2_set_related(&rqst[2]);

        rc = compound_send_recv(xid, tcon->ses, server,
                                flags, 3, rqst,
                                resp_buftype, rsp_iov);

        ioctl_rsp = rsp_iov[1].iov_base;

        /*
         * Open was successful and we got an ioctl response.
         */
        if (rc == 0) {
                /* See MS-FSCC 2.3.23 */

                reparse_buf = (struct reparse_data_buffer *)
                        ((char *)ioctl_rsp +
                         le32_to_cpu(ioctl_rsp->OutputOffset));
                plen = le32_to_cpu(ioctl_rsp->OutputCount);

                if (plen + le32_to_cpu(ioctl_rsp->OutputOffset) >
                    rsp_iov[1].iov_len) {
                        cifs_tcon_dbg(FYI, "srv returned invalid ioctl len: %d\n",
                                 plen);
                        rc = -EIO;
                        goto query_rp_exit;
                }
                *tag = le32_to_cpu(reparse_buf->ReparseTag);
        }

 query_rp_exit:
        kfree(utf16_path);
        SMB2_open_free(&rqst[0]);
        SMB2_ioctl_free(&rqst[1]);
        SMB2_close_free(&rqst[2]);
        free_rsp_buf(resp_buftype[0], rsp_iov[0].iov_base);
        free_rsp_buf(resp_buftype[1], rsp_iov[1].iov_base);
        free_rsp_buf(resp_buftype[2], rsp_iov[2].iov_base);
        return rc;
}

static struct cifs_ntsd *
get_smb2_acl_by_fid(struct cifs_sb_info *cifs_sb,
                    const struct cifs_fid *cifsfid, u32 *pacllen, u32 info)
{
        struct cifs_ntsd *pntsd = NULL;
        unsigned int xid;
        int rc = -EOPNOTSUPP;
        struct tcon_link *tlink = cifs_sb_tlink(cifs_sb);

        if (IS_ERR(tlink))
                return ERR_CAST(tlink);

        xid = get_xid();
        cifs_dbg(FYI, "trying to get acl\n");

        rc = SMB2_query_acl(xid, tlink_tcon(tlink), cifsfid->persistent_fid,
                            cifsfid->volatile_fid, (void **)&pntsd, pacllen,
                            info);
        free_xid(xid);

        cifs_put_tlink(tlink);

        cifs_dbg(FYI, "%s: rc = %d ACL len %d\n", __func__, rc, *pacllen);
        if (rc)
                return ERR_PTR(rc);
        return pntsd;

}

static struct cifs_ntsd *
get_smb2_acl_by_path(struct cifs_sb_info *cifs_sb,
                     const char *path, u32 *pacllen, u32 info)
{
        struct cifs_ntsd *pntsd = NULL;
        u8 oplock = SMB2_OPLOCK_LEVEL_NONE;
        unsigned int xid;
        int rc;
        struct cifs_tcon *tcon;
        struct tcon_link *tlink = cifs_sb_tlink(cifs_sb);
        struct cifs_fid fid;
        struct cifs_open_parms oparms;
        __le16 *utf16_path;

        cifs_dbg(FYI, "get smb3 acl for path %s\n", path);
        if (IS_ERR(tlink))
                return ERR_CAST(tlink);

        tcon = tlink_tcon(tlink);
        xid = get_xid();

        utf16_path = cifs_convert_path_to_utf16(path, cifs_sb);
        if (!utf16_path) {
                rc = -ENOMEM;
                free_xid(xid);
                return ERR_PTR(rc);
        }

        oparms.tcon = tcon;
        oparms.desired_access = READ_CONTROL;
        oparms.disposition = FILE_OPEN;
        /*
         * When querying an ACL, even if the file is a symlink we want to open
         * the source not the target, and so the protocol requires that the
         * client specify this flag when opening a reparse point
         */
        oparms.create_options = cifs_create_options(cifs_sb, 0) | OPEN_REPARSE_POINT;
        oparms.fid = &fid;
        oparms.reconnect = false;

        if (info & SACL_SECINFO)
                oparms.desired_access |= SYSTEM_SECURITY;

        rc = SMB2_open(xid, &oparms, utf16_path, &oplock, NULL, NULL, NULL,
                       NULL);
        kfree(utf16_path);
        if (!rc) {
                rc = SMB2_query_acl(xid, tlink_tcon(tlink), fid.persistent_fid,
                                    fid.volatile_fid, (void **)&pntsd, pacllen,
                                    info);
                SMB2_close(xid, tcon, fid.persistent_fid, fid.volatile_fid);
        }

        cifs_put_tlink(tlink);
        free_xid(xid);

        cifs_dbg(FYI, "%s: rc = %d ACL len %d\n", __func__, rc, *pacllen);
        if (rc)
                return ERR_PTR(rc);
        return pntsd;
}

static int
set_smb2_acl(struct cifs_ntsd *pnntsd, __u32 acllen,
                struct inode *inode, const char *path, int aclflag)
{
        u8 oplock = SMB2_OPLOCK_LEVEL_NONE;
        unsigned int xid;
        int rc, access_flags = 0;
        struct cifs_tcon *tcon;
        struct cifs_sb_info *cifs_sb = CIFS_SB(inode->i_sb);
        struct tcon_link *tlink = cifs_sb_tlink(cifs_sb);
        struct cifs_fid fid;
        struct cifs_open_parms oparms;
        __le16 *utf16_path;

        cifs_dbg(FYI, "set smb3 acl for path %s\n", path);
        if (IS_ERR(tlink))
                return PTR_ERR(tlink);

        tcon = tlink_tcon(tlink);
        xid = get_xid();

        if (aclflag & CIFS_ACL_OWNER || aclflag & CIFS_ACL_GROUP)
                access_flags |= WRITE_OWNER;
        if (aclflag & CIFS_ACL_SACL)
                access_flags |= SYSTEM_SECURITY;
        if (aclflag & CIFS_ACL_DACL)
                access_flags |= WRITE_DAC;

        utf16_path = cifs_convert_path_to_utf16(path, cifs_sb);
        if (!utf16_path) {
                rc = -ENOMEM;
                free_xid(xid);
                return rc;
        }

        oparms.tcon = tcon;
        oparms.desired_access = access_flags;
        oparms.create_options = cifs_create_options(cifs_sb, 0);
        oparms.disposition = FILE_OPEN;
        oparms.path = path;
        oparms.fid = &fid;
        oparms.reconnect = false;

        rc = SMB2_open(xid, &oparms, utf16_path, &oplock, NULL, NULL,
                       NULL, NULL);
        kfree(utf16_path);
        if (!rc) {
                rc = SMB2_set_acl(xid, tlink_tcon(tlink), fid.persistent_fid,
                            fid.volatile_fid, pnntsd, acllen, aclflag);
                SMB2_close(xid, tcon, fid.persistent_fid, fid.volatile_fid);
        }

        cifs_put_tlink(tlink);
        free_xid(xid);
        return rc;
}

/* Retrieve an ACL from the server */
static struct cifs_ntsd *
get_smb2_acl(struct cifs_sb_info *cifs_sb,
             struct inode *inode, const char *path,
             u32 *pacllen, u32 info)
{
        struct cifs_ntsd *pntsd = NULL;
        struct cifsFileInfo *open_file = NULL;

        if (inode && !(info & SACL_SECINFO))
                open_file = find_readable_file(CIFS_I(inode), true);
        if (!open_file || (info & SACL_SECINFO))
                return get_smb2_acl_by_path(cifs_sb, path, pacllen, info);

        pntsd = get_smb2_acl_by_fid(cifs_sb, &open_file->fid, pacllen, info);
        cifsFileInfo_put(open_file);
        return pntsd;
}

static long smb3_zero_data(struct file *file, struct cifs_tcon *tcon,
                             loff_t offset, loff_t len, unsigned int xid)
{
        struct cifsFileInfo *cfile = file->private_data;
        struct file_zero_data_information fsctl_buf;

        cifs_dbg(FYI, "Offset %lld len %lld\n", offset, len);

        fsctl_buf.FileOffset = cpu_to_le64(offset);
        fsctl_buf.BeyondFinalZero = cpu_to_le64(offset + len);

        return SMB2_ioctl(xid, tcon, cfile->fid.persistent_fid,
                          cfile->fid.volatile_fid, FSCTL_SET_ZERO_DATA,
                          (char *)&fsctl_buf,
                          sizeof(struct file_zero_data_information),
                          0, NULL, NULL);
}

static long smb3_zero_range(struct file *file, struct cifs_tcon *tcon,
                            loff_t offset, loff_t len, bool keep_size)
{
        struct cifs_ses *ses = tcon->ses;
        struct inode *inode = file_inode(file);
        struct cifsInodeInfo *cifsi = CIFS_I(inode);
        struct cifsFileInfo *cfile = file->private_data;
        long rc;
        unsigned int xid;
        __le64 eof;

        xid = get_xid();

        trace_smb3_zero_enter(xid, cfile->fid.persistent_fid, tcon->tid,
                              ses->Suid, offset, len);

        inode_lock(inode);
        filemap_invalidate_lock(inode->i_mapping);

        /*
         * We zero the range through ioctl, so we need remove the page caches
         * first, otherwise the data may be inconsistent with the server.
         */
        truncate_pagecache_range(inode, offset, offset + len - 1);

        /* if file not oplocked can't be sure whether asking to extend size */
        rc = -EOPNOTSUPP;
        if (keep_size == false && !CIFS_CACHE_READ(cifsi))
                goto zero_range_exit;

        rc = smb3_zero_data(file, tcon, offset, len, xid);
        if (rc < 0)
                goto zero_range_exit;

        /*
         * do we also need to change the size of the file?
         */
        if (keep_size == false && i_size_read(inode) < offset + len) {
                eof = cpu_to_le64(offset + len);
                rc = SMB2_set_eof(xid, tcon, cfile->fid.persistent_fid,
                                  cfile->fid.volatile_fid, cfile->pid, &eof);
        }

 zero_range_exit:
        filemap_invalidate_unlock(inode->i_mapping);
        inode_unlock(inode);
        free_xid(xid);
        if (rc)
                trace_smb3_zero_err(xid, cfile->fid.persistent_fid, tcon->tid,
                              ses->Suid, offset, len, rc);
        else
                trace_smb3_zero_done(xid, cfile->fid.persistent_fid, tcon->tid,
                              ses->Suid, offset, len);
        return rc;
}

static long smb3_punch_hole(struct file *file, struct cifs_tcon *tcon,
                            loff_t offset, loff_t len)
{
        struct inode *inode = file_inode(file);
        struct cifsFileInfo *cfile = file->private_data;
        struct file_zero_data_information fsctl_buf;
        long rc;
        unsigned int xid;
        __u8 set_sparse = 1;

        xid = get_xid();

        inode_lock(inode);
        /* Need to make file sparse, if not already, before freeing range. */
        /* Consider adding equivalent for compressed since it could also work */
        if (!smb2_set_sparse(xid, tcon, cfile, inode, set_sparse)) {
                rc = -EOPNOTSUPP;
                goto out;
        }

        filemap_invalidate_lock(inode->i_mapping);
        /*
         * We implement the punch hole through ioctl, so we need remove the page
         * caches first, otherwise the data may be inconsistent with the server.
         */
        truncate_pagecache_range(inode, offset, offset + len - 1);

        cifs_dbg(FYI, "Offset %lld len %lld\n", offset, len);

        fsctl_buf.FileOffset = cpu_to_le64(offset);
        fsctl_buf.BeyondFinalZero = cpu_to_le64(offset + len);

        rc = SMB2_ioctl(xid, tcon, cfile->fid.persistent_fid,
                        cfile->fid.volatile_fid, FSCTL_SET_ZERO_DATA,
                        (char *)&fsctl_buf,
                        sizeof(struct file_zero_data_information),
                        CIFSMaxBufSize, NULL, NULL);
        filemap_invalidate_unlock(inode->i_mapping);
out:
        inode_unlock(inode);
        free_xid(xid);
        return rc;
}

static int smb3_simple_fallocate_write_range(unsigned int xid,
                                             struct cifs_tcon *tcon,
                                             struct cifsFileInfo *cfile,
                                             loff_t off, loff_t len,
                                             char *buf)
{
        struct cifs_io_parms io_parms = {0};
        int nbytes;
        int rc = 0;
        struct kvec iov[2];

        io_parms.netfid = cfile->fid.netfid;
        io_parms.pid = current->tgid;
        io_parms.tcon = tcon;
        io_parms.persistent_fid = cfile->fid.persistent_fid;
        io_parms.volatile_fid = cfile->fid.volatile_fid;

        while (len) {
                io_parms.offset = off;
                io_parms.length = len;
                if (io_parms.length > SMB2_MAX_BUFFER_SIZE)
                        io_parms.length = SMB2_MAX_BUFFER_SIZE;
                /* iov[0] is reserved for smb header */
                iov[1].iov_base = buf;
                iov[1].iov_len = io_parms.length;
                rc = SMB2_write(xid, &io_parms, &nbytes, iov, 1);
                if (rc)
                        break;
                if (nbytes > len)
                        return -EINVAL;
                buf += nbytes;
                off += nbytes;
                len -= nbytes;
        }
        return rc;
}

static int smb3_simple_fallocate_range(unsigned int xid,
                                       struct cifs_tcon *tcon,
                                       struct cifsFileInfo *cfile,
                                       loff_t off, loff_t len)
{
        struct file_allocated_range_buffer in_data, *out_data = NULL, *tmp_data;
        u32 out_data_len;
        char *buf = NULL;
        loff_t l;
        int rc;

        in_data.file_offset = cpu_to_le64(off);
        in_data.length = cpu_to_le64(len);
        rc = SMB2_ioctl(xid, tcon, cfile->fid.persistent_fid,
                        cfile->fid.volatile_fid,
                        FSCTL_QUERY_ALLOCATED_RANGES,
                        (char *)&in_data, sizeof(in_data),
                        1024 * sizeof(struct file_allocated_range_buffer),
                        (char **)&out_data, &out_data_len);
        if (rc)
                goto out;

        buf = kzalloc(1024 * 1024, GFP_KERNEL);
        if (buf == NULL) {
                rc = -ENOMEM;
                goto out;
        }

        tmp_data = out_data;
        while (len) {
                /*
                 * The rest of the region is unmapped so write it all.
                 */
                if (out_data_len == 0) {
                        rc = smb3_simple_fallocate_write_range(xid, tcon,
                                               cfile, off, len, buf);
                        goto out;
                }

                if (out_data_len < sizeof(struct file_allocated_range_buffer)) {
                        rc = -EINVAL;
                        goto out;
                }

                if (off < le64_to_cpu(tmp_data->file_offset)) {
                        /*
                         * We are at a hole. Write until the end of the region
                         * or until the next allocated data,
                         * whichever comes next.
                         */
                        l = le64_to_cpu(tmp_data->file_offset) - off;
                        if (len < l)
                                l = len;
                        rc = smb3_simple_fallocate_write_range(xid, tcon,
                                               cfile, off, l, buf);
                        if (rc)
                                goto out;
                        off = off + l;
                        len = len - l;
                        if (len == 0)
                                goto out;
                }
                /*
                 * We are at a section of allocated data, just skip forward
                 * until the end of the data or the end of the region
                 * we are supposed to fallocate, whichever comes first.
                 */
                l = le64_to_cpu(tmp_data->length);
                if (len < l)
                        l = len;
                off += l;
                len -= l;

                tmp_data = &tmp_data[1];
                out_data_len -= sizeof(struct file_allocated_range_buffer);
        }

 out:
        kfree(out_data);
        kfree(buf);
        return rc;
}


static long smb3_simple_falloc(struct file *file, struct cifs_tcon *tcon,
                            loff_t off, loff_t len, bool keep_size)
{
        struct inode *inode;
        struct cifsInodeInfo *cifsi;
        struct cifsFileInfo *cfile = file->private_data;
        long rc = -EOPNOTSUPP;
        unsigned int xid;
        __le64 eof;

        xid = get_xid();

        inode = d_inode(cfile->dentry);
        cifsi = CIFS_I(inode);

        trace_smb3_falloc_enter(xid, cfile->fid.persistent_fid, tcon->tid,
                                tcon->ses->Suid, off, len);
        /* if file not oplocked can't be sure whether asking to extend size */
        if (!CIFS_CACHE_READ(cifsi))
                if (keep_size == false) {
                        trace_smb3_falloc_err(xid, cfile->fid.persistent_fid,
                                tcon->tid, tcon->ses->Suid, off, len, rc);
                        free_xid(xid);
                        return rc;
                }

        /*
         * Extending the file
         */
        if ((keep_size == false) && i_size_read(inode) < off + len) {
                rc = inode_newsize_ok(inode, off + len);
                if (rc)
                        goto out;

                if (cifsi->cifsAttrs & FILE_ATTRIBUTE_SPARSE_FILE)
                        smb2_set_sparse(xid, tcon, cfile, inode, false);

                eof = cpu_to_le64(off + len);
                rc = SMB2_set_eof(xid, tcon, cfile->fid.persistent_fid,
                                  cfile->fid.volatile_fid, cfile->pid, &eof);
                if (rc == 0) {
                        cifsi->server_eof = off + len;
                        cifs_setsize(inode, off + len);
                        cifs_truncate_page(inode->i_mapping, inode->i_size);
                        truncate_setsize(inode, off + len);
                }
                goto out;
        }

        /*
         * Files are non-sparse by default so falloc may be a no-op
         * Must check if file sparse. If not sparse, and since we are not
         * extending then no need to do anything since file already allocated
         */
        if ((cifsi->cifsAttrs & FILE_ATTRIBUTE_SPARSE_FILE) == 0) {
                rc = 0;
                goto out;
        }

        if (keep_size == true) {
                /*
                 * We can not preallocate pages beyond the end of the file
                 * in SMB2
                 */
                if (off >= i_size_read(inode)) {
                        rc = 0;
                        goto out;
                }
                /*
                 * For fallocates that are partially beyond the end of file,
                 * clamp len so we only fallocate up to the end of file.
                 */
                if (off + len > i_size_read(inode)) {
                        len = i_size_read(inode) - off;
                }
        }

        if ((keep_size == true) || (i_size_read(inode) >= off + len)) {
                /*
                 * At this point, we are trying to fallocate an internal
                 * regions of a sparse file. Since smb2 does not have a
                 * fallocate command we have two otions on how to emulate this.
                 * We can either turn the entire file to become non-sparse
                 * which we only do if the fallocate is for virtually
                 * the whole file,  or we can overwrite the region with zeroes
                 * using SMB2_write, which could be prohibitevly expensive
                 * if len is large.
                 */
                /*
                 * We are only trying to fallocate a small region so
                 * just write it with zero.
                 */
                if (len <= 1024 * 1024) {
                        rc = smb3_simple_fallocate_range(xid, tcon, cfile,
                                                         off, len);
                        goto out;
                }

                /*
                 * Check if falloc starts within first few pages of file
                 * and ends within a few pages of the end of file to
                 * ensure that most of file is being forced to be
                 * fallocated now. If so then setting whole file sparse
                 * ie potentially making a few extra pages at the beginning
                 * or end of the file non-sparse via set_sparse is harmless.
                 */
                if ((off > 8192) || (off + len + 8192 < i_size_read(inode))) {
                        rc = -EOPNOTSUPP;
                        goto out;
                }
        }

        smb2_set_sparse(xid, tcon, cfile, inode, false);
        rc = 0;

out:
        if (rc)
                trace_smb3_falloc_err(xid, cfile->fid.persistent_fid, tcon->tid,
                                tcon->ses->Suid, off, len, rc);
        else
                trace_smb3_falloc_done(xid, cfile->fid.persistent_fid, tcon->tid,
                                tcon->ses->Suid, off, len);

        free_xid(xid);
        return rc;
}

static long smb3_collapse_range(struct file *file, struct cifs_tcon *tcon,
                            loff_t off, loff_t len)
{
        int rc;
        unsigned int xid;
        struct inode *inode = file_inode(file);
        struct cifsFileInfo *cfile = file->private_data;
        struct cifsInodeInfo *cifsi = CIFS_I(inode);
        __le64 eof;
        loff_t old_eof;

        xid = get_xid();

        inode_lock(inode);

        old_eof = i_size_read(inode);
        if ((off >= old_eof) ||
            off + len >= old_eof) {
                rc = -EINVAL;
                goto out;
        }

        filemap_invalidate_lock(inode->i_mapping);
        rc = filemap_write_and_wait_range(inode->i_mapping, off, old_eof - 1);
        if (rc < 0)
                goto out_2;

        truncate_pagecache_range(inode, off, old_eof);

        rc = smb2_copychunk_range(xid, cfile, cfile, off + len,
                                  old_eof - off - len, off);
        if (rc < 0)
                goto out_2;

        eof = cpu_to_le64(old_eof - len);
        rc = SMB2_set_eof(xid, tcon, cfile->fid.persistent_fid,
                          cfile->fid.volatile_fid, cfile->pid, &eof);
        if (rc < 0)
                goto out_2;

        rc = 0;

        cifsi->server_eof = i_size_read(inode) - len;
        truncate_setsize(inode, cifsi->server_eof);
        fscache_resize_cookie(cifs_inode_cookie(inode), cifsi->server_eof);
out_2:
        filemap_invalidate_unlock(inode->i_mapping);
 out:
        inode_unlock(inode);
        free_xid(xid);
        return rc;
}

static long smb3_insert_range(struct file *file, struct cifs_tcon *tcon,
                              loff_t off, loff_t len)
{
        int rc;
        unsigned int xid;
        struct cifsFileInfo *cfile = file->private_data;
        struct inode *inode = file_inode(file);
        __le64 eof;
        __u64  count, old_eof;

        xid = get_xid();

        inode_lock(inode);

        old_eof = i_size_read(inode);
        if (off >= old_eof) {
                rc = -EINVAL;
                goto out;
        }

        count = old_eof - off;
        eof = cpu_to_le64(old_eof + len);

        filemap_invalidate_lock(inode->i_mapping);
        rc = filemap_write_and_wait_range(inode->i_mapping, off, old_eof + len - 1);
        if (rc < 0)
                goto out_2;
        truncate_pagecache_range(inode, off, old_eof);

        rc = SMB2_set_eof(xid, tcon, cfile->fid.persistent_fid,
                          cfile->fid.volatile_fid, cfile->pid, &eof);
        if (rc < 0)
                goto out_2;

        rc = smb2_copychunk_range(xid, cfile, cfile, off, count, off + len);
        if (rc < 0)
                goto out_2;

        rc = smb3_zero_data(file, tcon, off, len, xid);
        if (rc < 0)
                goto out_2;

        rc = 0;
out_2:
        filemap_invalidate_unlock(inode->i_mapping);
 out:
        inode_unlock(inode);
        free_xid(xid);
        return rc;
}

static loff_t smb3_llseek(struct file *file, struct cifs_tcon *tcon, loff_t offset, int whence)
{
        struct cifsFileInfo *wrcfile, *cfile = file->private_data;
        struct cifsInodeInfo *cifsi;
        struct inode *inode;
        int rc = 0;
        struct file_allocated_range_buffer in_data, *out_data = NULL;
        u32 out_data_len;
        unsigned int xid;

        if (whence != SEEK_HOLE && whence != SEEK_DATA)
                return generic_file_llseek(file, offset, whence);

        inode = d_inode(cfile->dentry);
        cifsi = CIFS_I(inode);

        if (offset < 0 || offset >= i_size_read(inode))
                return -ENXIO;

        xid = get_xid();
        /*
         * We need to be sure that all dirty pages are written as they
         * might fill holes on the server.
         * Note that we also MUST flush any written pages since at least
         * some servers (Windows2016) will not reflect recent writes in
         * QUERY_ALLOCATED_RANGES until SMB2_flush is called.
         */
        wrcfile = find_writable_file(cifsi, FIND_WR_ANY);
        if (wrcfile) {
                filemap_write_and_wait(inode->i_mapping);
                smb2_flush_file(xid, tcon, &wrcfile->fid);
                cifsFileInfo_put(wrcfile);
        }

        if (!(cifsi->cifsAttrs & FILE_ATTRIBUTE_SPARSE_FILE)) {
                if (whence == SEEK_HOLE)
                        offset = i_size_read(inode);
                goto lseek_exit;
        }

        in_data.file_offset = cpu_to_le64(offset);
        in_data.length = cpu_to_le64(i_size_read(inode));

        rc = SMB2_ioctl(xid, tcon, cfile->fid.persistent_fid,
                        cfile->fid.volatile_fid,
                        FSCTL_QUERY_ALLOCATED_RANGES,
                        (char *)&in_data, sizeof(in_data),
                        sizeof(struct file_allocated_range_buffer),
                        (char **)&out_data, &out_data_len);
        if (rc == -E2BIG)
                rc = 0;
        if (rc)
                goto lseek_exit;

        if (whence == SEEK_HOLE && out_data_len == 0)
                goto lseek_exit;

        if (whence == SEEK_DATA && out_data_len == 0) {
                rc = -ENXIO;
                goto lseek_exit;
        }

        if (out_data_len < sizeof(struct file_allocated_range_buffer)) {
                rc = -EINVAL;
                goto lseek_exit;
        }
        if (whence == SEEK_DATA) {
                offset = le64_to_cpu(out_data->file_offset);
                goto lseek_exit;
        }
        if (offset < le64_to_cpu(out_data->file_offset))
                goto lseek_exit;

        offset = le64_to_cpu(out_data->file_offset) + le64_to_cpu(out_data->length);

 lseek_exit:
        free_xid(xid);
        kfree(out_data);
        if (!rc)
                return vfs_setpos(file, offset, inode->i_sb->s_maxbytes);
        else
                return rc;
}

static int smb3_fiemap(struct cifs_tcon *tcon,
                       struct cifsFileInfo *cfile,
                       struct fiemap_extent_info *fei, u64 start, u64 len)
{
        unsigned int xid;
        struct file_allocated_range_buffer in_data, *out_data;
        u32 out_data_len;
        int i, num, rc, flags, last_blob;
        u64 next;

        rc = fiemap_prep(d_inode(cfile->dentry), fei, start, &len, 0);
        if (rc)
                return rc;

        xid = get_xid();
 again:
        in_data.file_offset = cpu_to_le64(start);
        in_data.length = cpu_to_le64(len);

        rc = SMB2_ioctl(xid, tcon, cfile->fid.persistent_fid,
                        cfile->fid.volatile_fid,
                        FSCTL_QUERY_ALLOCATED_RANGES,
                        (char *)&in_data, sizeof(in_data),
                        1024 * sizeof(struct file_allocated_range_buffer),
                        (char **)&out_data, &out_data_len);
        if (rc == -E2BIG) {
                last_blob = 0;
                rc = 0;
        } else
                last_blob = 1;
        if (rc)
                goto out;

        if (out_data_len && out_data_len < sizeof(struct file_allocated_range_buffer)) {
                rc = -EINVAL;
                goto out;
        }
        if (out_data_len % sizeof(struct file_allocated_range_buffer)) {
                rc = -EINVAL;
                goto out;
        }

        num = out_data_len / sizeof(struct file_allocated_range_buffer);
        for (i = 0; i < num; i++) {
                flags = 0;
                if (i == num - 1 && last_blob)
                        flags |= FIEMAP_EXTENT_LAST;

                rc = fiemap_fill_next_extent(fei,
                                le64_to_cpu(out_data[i].file_offset),
                                le64_to_cpu(out_data[i].file_offset),
                                le64_to_cpu(out_data[i].length),
                                flags);
                if (rc < 0)
                        goto out;
                if (rc == 1) {
                        rc = 0;
                        goto out;
                }
        }

        if (!last_blob) {
                next = le64_to_cpu(out_data[num - 1].file_offset) +
                  le64_to_cpu(out_data[num - 1].length);
                len = len - (next - start);
                start = next;
                goto again;
        }

 out:
        free_xid(xid);
        kfree(out_data);
        return rc;
}

static long smb3_fallocate(struct file *file, struct cifs_tcon *tcon, int mode,
                           loff_t off, loff_t len)
{
        /* KEEP_SIZE already checked for by do_fallocate */
        if (mode & FALLOC_FL_PUNCH_HOLE)
                return smb3_punch_hole(file, tcon, off, len);
        else if (mode & FALLOC_FL_ZERO_RANGE) {
                if (mode & FALLOC_FL_KEEP_SIZE)
                        return smb3_zero_range(file, tcon, off, len, true);
                return smb3_zero_range(file, tcon, off, len, false);
        } else if (mode == FALLOC_FL_KEEP_SIZE)
                return smb3_simple_falloc(file, tcon, off, len, true);
        else if (mode == FALLOC_FL_COLLAPSE_RANGE)
                return smb3_collapse_range(file, tcon, off, len);
        else if (mode == FALLOC_FL_INSERT_RANGE)
                return smb3_insert_range(file, tcon, off, len);
        else if (mode == 0)
                return smb3_simple_falloc(file, tcon, off, len, false);

        return -EOPNOTSUPP;
}

static void
smb2_downgrade_oplock(struct TCP_Server_Info *server,
                      struct cifsInodeInfo *cinode, __u32 oplock,
                      unsigned int epoch, bool *purge_cache)
{
        server->ops->set_oplock_level(cinode, oplock, 0, NULL);
}

static void
smb21_set_oplock_level(struct cifsInodeInfo *cinode, __u32 oplock,
                       unsigned int epoch, bool *purge_cache);

static void
smb3_downgrade_oplock(struct TCP_Server_Info *server,
                       struct cifsInodeInfo *cinode, __u32 oplock,
                       unsigned int epoch, bool *purge_cache)
{
        unsigned int old_state = cinode->oplock;
        unsigned int old_epoch = cinode->epoch;
        unsigned int new_state;

        if (epoch > old_epoch) {
                smb21_set_oplock_level(cinode, oplock, 0, NULL);
                cinode->epoch = epoch;
        }

        new_state = cinode->oplock;
        *purge_cache = false;

        if ((old_state & CIFS_CACHE_READ_FLG) != 0 &&
            (new_state & CIFS_CACHE_READ_FLG) == 0)
                *purge_cache = true;
        else if (old_state == new_state && (epoch - old_epoch > 1))
                *purge_cache = true;
}

static void
smb2_set_oplock_level(struct cifsInodeInfo *cinode, __u32 oplock,
                      unsigned int epoch, bool *purge_cache)
{
        oplock &= 0xFF;
        cinode->lease_granted = false;
        if (oplock == SMB2_OPLOCK_LEVEL_NOCHANGE)
                return;
        if (oplock == SMB2_OPLOCK_LEVEL_BATCH) {
                cinode->oplock = CIFS_CACHE_RHW_FLG;
                cifs_dbg(FYI, "Batch Oplock granted on inode %p\n",
                         &cinode->netfs.inode);
        } else if (oplock == SMB2_OPLOCK_LEVEL_EXCLUSIVE) {
                cinode->oplock = CIFS_CACHE_RW_FLG;
                cifs_dbg(FYI, "Exclusive Oplock granted on inode %p\n",
                         &cinode->netfs.inode);
        } else if (oplock == SMB2_OPLOCK_LEVEL_II) {
                cinode->oplock = CIFS_CACHE_READ_FLG;
                cifs_dbg(FYI, "Level II Oplock granted on inode %p\n",
                         &cinode->netfs.inode);
        } else
                cinode->oplock = 0;
}

static void
smb21_set_oplock_level(struct cifsInodeInfo *cinode, __u32 oplock,
                       unsigned int epoch, bool *purge_cache)
{
        char message[5] = {0};
        unsigned int new_oplock = 0;

        oplock &= 0xFF;
        cinode->lease_granted = true;
        if (oplock == SMB2_OPLOCK_LEVEL_NOCHANGE)
                return;

        /* Check if the server granted an oplock rather than a lease */
        if (oplock & SMB2_OPLOCK_LEVEL_EXCLUSIVE)
                return smb2_set_oplock_level(cinode, oplock, epoch,
                                             purge_cache);

        if (oplock & SMB2_LEASE_READ_CACHING_HE) {
                new_oplock |= CIFS_CACHE_READ_FLG;
                strcat(message, "R");
        }
        if (oplock & SMB2_LEASE_HANDLE_CACHING_HE) {
                new_oplock |= CIFS_CACHE_HANDLE_FLG;
                strcat(message, "H");
        }
        if (oplock & SMB2_LEASE_WRITE_CACHING_HE) {
                new_oplock |= CIFS_CACHE_WRITE_FLG;
                strcat(message, "W");
        }
        if (!new_oplock)
                strncpy(message, "None", sizeof(message));

        cinode->oplock = new_oplock;
        cifs_dbg(FYI, "%s Lease granted on inode %p\n", message,
                 &cinode->netfs.inode);
}

static void
smb3_set_oplock_level(struct cifsInodeInfo *cinode, __u32 oplock,
                      unsigned int epoch, bool *purge_cache)
{
        unsigned int old_oplock = cinode->oplock;

        smb21_set_oplock_level(cinode, oplock, epoch, purge_cache);

        if (purge_cache) {
                *purge_cache = false;
                if (old_oplock == CIFS_CACHE_READ_FLG) {
                        if (cinode->oplock == CIFS_CACHE_READ_FLG &&
                            (epoch - cinode->epoch > 0))
                                *purge_cache = true;
                        else if (cinode->oplock == CIFS_CACHE_RH_FLG &&
                                 (epoch - cinode->epoch > 1))
                                *purge_cache = true;
                        else if (cinode->oplock == CIFS_CACHE_RHW_FLG &&
                                 (epoch - cinode->epoch > 1))
                                *purge_cache = true;
                        else if (cinode->oplock == 0 &&
                                 (epoch - cinode->epoch > 0))
                                *purge_cache = true;
                } else if (old_oplock == CIFS_CACHE_RH_FLG) {
                        if (cinode->oplock == CIFS_CACHE_RH_FLG &&
                            (epoch - cinode->epoch > 0))
                                *purge_cache = true;
                        else if (cinode->oplock == CIFS_CACHE_RHW_FLG &&
                                 (epoch - cinode->epoch > 1))
                                *purge_cache = true;
                }
                cinode->epoch = epoch;
        }
}

#ifdef CONFIG_CIFS_ALLOW_INSECURE_LEGACY
static bool
smb2_is_read_op(__u32 oplock)
{
        return oplock == SMB2_OPLOCK_LEVEL_II;
}
#endif /* CIFS_ALLOW_INSECURE_LEGACY */

static bool
smb21_is_read_op(__u32 oplock)
{
        return (oplock & SMB2_LEASE_READ_CACHING_HE) &&
               !(oplock & SMB2_LEASE_WRITE_CACHING_HE);
}

static __le32
map_oplock_to_lease(u8 oplock)
{
        if (oplock == SMB2_OPLOCK_LEVEL_EXCLUSIVE)
                return SMB2_LEASE_WRITE_CACHING_LE | SMB2_LEASE_READ_CACHING_LE;
        else if (oplock == SMB2_OPLOCK_LEVEL_II)
                return SMB2_LEASE_READ_CACHING_LE;
        else if (oplock == SMB2_OPLOCK_LEVEL_BATCH)
                return SMB2_LEASE_HANDLE_CACHING_LE | SMB2_LEASE_READ_CACHING_LE |
                       SMB2_LEASE_WRITE_CACHING_LE;
        return 0;
}

static char *
smb2_create_lease_buf(u8 *lease_key, u8 oplock)
{
        struct create_lease *buf;

        buf = kzalloc(sizeof(struct create_lease), GFP_KERNEL);
        if (!buf)
                return NULL;

        memcpy(&buf->lcontext.LeaseKey, lease_key, SMB2_LEASE_KEY_SIZE);
        buf->lcontext.LeaseState = map_oplock_to_lease(oplock);

        buf->ccontext.DataOffset = cpu_to_le16(offsetof
                                        (struct create_lease, lcontext));
        buf->ccontext.DataLength = cpu_to_le32(sizeof(struct lease_context));
        buf->ccontext.NameOffset = cpu_to_le16(offsetof
                                (struct create_lease, Name));
        buf->ccontext.NameLength = cpu_to_le16(4);
        /* SMB2_CREATE_REQUEST_LEASE is "RqLs" */
        buf->Name[0] = 'R';
        buf->Name[1] = 'q';
        buf->Name[2] = 'L';
        buf->Name[3] = 's';
        return (char *)buf;
}

static char *
smb3_create_lease_buf(u8 *lease_key, u8 oplock)
{
        struct create_lease_v2 *buf;

        buf = kzalloc(sizeof(struct create_lease_v2), GFP_KERNEL);
        if (!buf)
                return NULL;

        memcpy(&buf->lcontext.LeaseKey, lease_key, SMB2_LEASE_KEY_SIZE);
        buf->lcontext.LeaseState = map_oplock_to_lease(oplock);

        buf->ccontext.DataOffset = cpu_to_le16(offsetof
                                        (struct create_lease_v2, lcontext));
        buf->ccontext.DataLength = cpu_to_le32(sizeof(struct lease_context_v2));
        buf->ccontext.NameOffset = cpu_to_le16(offsetof
                                (struct create_lease_v2, Name));
        buf->ccontext.NameLength = cpu_to_le16(4);
        /* SMB2_CREATE_REQUEST_LEASE is "RqLs" */
        buf->Name[0] = 'R';
        buf->Name[1] = 'q';
        buf->Name[2] = 'L';
        buf->Name[3] = 's';
        return (char *)buf;
}

static __u8
smb2_parse_lease_buf(void *buf, unsigned int *epoch, char *lease_key)
{
        struct create_lease *lc = (struct create_lease *)buf;

        *epoch = 0; /* not used */
        if (lc->lcontext.LeaseFlags & SMB2_LEASE_FLAG_BREAK_IN_PROGRESS_LE)
                return SMB2_OPLOCK_LEVEL_NOCHANGE;
        return le32_to_cpu(lc->lcontext.LeaseState);
}

static __u8
smb3_parse_lease_buf(void *buf, unsigned int *epoch, char *lease_key)
{
        struct create_lease_v2 *lc = (struct create_lease_v2 *)buf;

        *epoch = le16_to_cpu(lc->lcontext.Epoch);
        if (lc->lcontext.LeaseFlags & SMB2_LEASE_FLAG_BREAK_IN_PROGRESS_LE)
                return SMB2_OPLOCK_LEVEL_NOCHANGE;
        if (lease_key)
                memcpy(lease_key, &lc->lcontext.LeaseKey, SMB2_LEASE_KEY_SIZE);
        return le32_to_cpu(lc->lcontext.LeaseState);
}

static unsigned int
smb2_wp_retry_size(struct inode *inode)
{
        return min_t(unsigned int, CIFS_SB(inode->i_sb)->ctx->wsize,
                     SMB2_MAX_BUFFER_SIZE);
}

static bool
smb2_dir_needs_close(struct cifsFileInfo *cfile)
{
        return !cfile->invalidHandle;
}

static void
fill_transform_hdr(struct smb2_transform_hdr *tr_hdr, unsigned int orig_len,
                   struct smb_rqst *old_rq, __le16 cipher_type)
{
        struct smb2_hdr *shdr =
                        (struct smb2_hdr *)old_rq->rq_iov[0].iov_base;

        memset(tr_hdr, 0, sizeof(struct smb2_transform_hdr));
        tr_hdr->ProtocolId = SMB2_TRANSFORM_PROTO_NUM;
        tr_hdr->OriginalMessageSize = cpu_to_le32(orig_len);
        tr_hdr->Flags = cpu_to_le16(0x01);
        if ((cipher_type == SMB2_ENCRYPTION_AES128_GCM) ||
            (cipher_type == SMB2_ENCRYPTION_AES256_GCM))
                get_random_bytes(&tr_hdr->Nonce, SMB3_AES_GCM_NONCE);
        else
                get_random_bytes(&tr_hdr->Nonce, SMB3_AES_CCM_NONCE);
        memcpy(&tr_hdr->SessionId, &shdr->SessionId, 8);
}

/* We can not use the normal sg_set_buf() as we will sometimes pass a
 * stack object as buf.
 */
static inline void smb2_sg_set_buf(struct scatterlist *sg, const void *buf,
                                   unsigned int buflen)
{
        void *addr;
        /*
         * VMAP_STACK (at least) puts stack into the vmalloc address space
         */
        if (is_vmalloc_addr(buf))
                addr = vmalloc_to_page(buf);
        else
                addr = virt_to_page(buf);
        sg_set_page(sg, addr, buflen, offset_in_page(buf));
}

/* Assumes the first rqst has a transform header as the first iov.
 * I.e.
 * rqst[0].rq_iov[0]  is transform header
 * rqst[0].rq_iov[1+] data to be encrypted/decrypted
 * rqst[1+].rq_iov[0+] data to be encrypted/decrypted
 */
static struct scatterlist *
init_sg(int num_rqst, struct smb_rqst *rqst, u8 *sign)
{
        unsigned int sg_len;
        struct scatterlist *sg;
        unsigned int i;
        unsigned int j;
        unsigned int idx = 0;
        int skip;

        sg_len = 1;
        for (i = 0; i < num_rqst; i++)
                sg_len += rqst[i].rq_nvec + rqst[i].rq_npages;

        sg = kmalloc_array(sg_len, sizeof(struct scatterlist), GFP_KERNEL);
        if (!sg)
                return NULL;

        sg_init_table(sg, sg_len);
        for (i = 0; i < num_rqst; i++) {
                for (j = 0; j < rqst[i].rq_nvec; j++) {
                        /*
                         * The first rqst has a transform header where the
                         * first 20 bytes are not part of the encrypted blob
                         */
                        skip = (i == 0) && (j == 0) ? 20 : 0;
                        smb2_sg_set_buf(&sg[idx++],
                                        rqst[i].rq_iov[j].iov_base + skip,
                                        rqst[i].rq_iov[j].iov_len - skip);
                        }

                for (j = 0; j < rqst[i].rq_npages; j++) {
                        unsigned int len, offset;

                        rqst_page_get_length(&rqst[i], j, &len, &offset);
                        sg_set_page(&sg[idx++], rqst[i].rq_pages[j], len, offset);
                }
        }
        smb2_sg_set_buf(&sg[idx], sign, SMB2_SIGNATURE_SIZE);
        return sg;
}

static int
smb2_get_enc_key(struct TCP_Server_Info *server, __u64 ses_id, int enc, u8 *key)
{
        struct cifs_ses *ses;
        u8 *ses_enc_key;

        spin_lock(&cifs_tcp_ses_lock);
        list_for_each_entry(server, &cifs_tcp_ses_list, tcp_ses_list) {
                list_for_each_entry(ses, &server->smb_ses_list, smb_ses_list) {
                        if (ses->Suid == ses_id) {
                                spin_lock(&ses->ses_lock);
                                ses_enc_key = enc ? ses->smb3encryptionkey :
                                        ses->smb3decryptionkey;
                                memcpy(key, ses_enc_key, SMB3_ENC_DEC_KEY_SIZE);
                                spin_unlock(&ses->ses_lock);
                                spin_unlock(&cifs_tcp_ses_lock);
                                return 0;
                        }
                }
        }
        spin_unlock(&cifs_tcp_ses_lock);

        return -EAGAIN;
}
/*
 * Encrypt or decrypt @rqst message. @rqst[0] has the following format:
 * iov[0]   - transform header (associate data),
 * iov[1-N] - SMB2 header and pages - data to encrypt.
 * On success return encrypted data in iov[1-N] and pages, leave iov[0]
 * untouched.
 */
static int
crypt_message(struct TCP_Server_Info *server, int num_rqst,
              struct smb_rqst *rqst, int enc)
{
        struct smb2_transform_hdr *tr_hdr =
                (struct smb2_transform_hdr *)rqst[0].rq_iov[0].iov_base;
        unsigned int assoc_data_len = sizeof(struct smb2_transform_hdr) - 20;
        int rc = 0;
        struct scatterlist *sg;
        u8 sign[SMB2_SIGNATURE_SIZE] = {};
        u8 key[SMB3_ENC_DEC_KEY_SIZE];
        struct aead_request *req;
        char *iv;
        unsigned int iv_len;
        DECLARE_CRYPTO_WAIT(wait);
        struct crypto_aead *tfm;
        unsigned int crypt_len = le32_to_cpu(tr_hdr->OriginalMessageSize);

        rc = smb2_get_enc_key(server, le64_to_cpu(tr_hdr->SessionId), enc, key);
        if (rc) {
                cifs_server_dbg(VFS, "%s: Could not get %scryption key\n", __func__,
                         enc ? "en" : "de");
                return rc;
        }

        rc = smb3_crypto_aead_allocate(server);
        if (rc) {
                cifs_server_dbg(VFS, "%s: crypto alloc failed\n", __func__);
                return rc;
        }

        tfm = enc ? server->secmech.ccmaesencrypt :
                                                server->secmech.ccmaesdecrypt;

        if ((server->cipher_type == SMB2_ENCRYPTION_AES256_CCM) ||
                (server->cipher_type == SMB2_ENCRYPTION_AES256_GCM))
                rc = crypto_aead_setkey(tfm, key, SMB3_GCM256_CRYPTKEY_SIZE);
        else
                rc = crypto_aead_setkey(tfm, key, SMB3_GCM128_CRYPTKEY_SIZE);

        if (rc) {
                cifs_server_dbg(VFS, "%s: Failed to set aead key %d\n", __func__, rc);
                return rc;
        }

        rc = crypto_aead_setauthsize(tfm, SMB2_SIGNATURE_SIZE);
        if (rc) {
                cifs_server_dbg(VFS, "%s: Failed to set authsize %d\n", __func__, rc);
                return rc;
        }

        req = aead_request_alloc(tfm, GFP_KERNEL);
        if (!req) {
                cifs_server_dbg(VFS, "%s: Failed to alloc aead request\n", __func__);
                return -ENOMEM;
        }

        if (!enc) {
                memcpy(sign, &tr_hdr->Signature, SMB2_SIGNATURE_SIZE);
                crypt_len += SMB2_SIGNATURE_SIZE;
        }

        sg = init_sg(num_rqst, rqst, sign);
        if (!sg) {
                cifs_server_dbg(VFS, "%s: Failed to init sg\n", __func__);
                rc = -ENOMEM;
                goto free_req;
        }

        iv_len = crypto_aead_ivsize(tfm);
        iv = kzalloc(iv_len, GFP_KERNEL);
        if (!iv) {
                cifs_server_dbg(VFS, "%s: Failed to alloc iv\n", __func__);
                rc = -ENOMEM;
                goto free_sg;
        }

        if ((server->cipher_type == SMB2_ENCRYPTION_AES128_GCM) ||
            (server->cipher_type == SMB2_ENCRYPTION_AES256_GCM))
                memcpy(iv, (char *)tr_hdr->Nonce, SMB3_AES_GCM_NONCE);
        else {
                iv[0] = 3;
                memcpy(iv + 1, (char *)tr_hdr->Nonce, SMB3_AES_CCM_NONCE);
        }

        aead_request_set_crypt(req, sg, sg, crypt_len, iv);
        aead_request_set_ad(req, assoc_data_len);

        aead_request_set_callback(req, CRYPTO_TFM_REQ_MAY_BACKLOG,
                                  crypto_req_done, &wait);

        rc = crypto_wait_req(enc ? crypto_aead_encrypt(req)
                                : crypto_aead_decrypt(req), &wait);

        if (!rc && enc)
                memcpy(&tr_hdr->Signature, sign, SMB2_SIGNATURE_SIZE);

        kfree(iv);
free_sg:
        kfree(sg);
free_req:
        kfree(req);
        return rc;
}

void
smb3_free_compound_rqst(int num_rqst, struct smb_rqst *rqst)
{
        int i, j;

        for (i = 0; i < num_rqst; i++) {
                if (rqst[i].rq_pages) {
                        for (j = rqst[i].rq_npages - 1; j >= 0; j--)
                                put_page(rqst[i].rq_pages[j]);
                        kfree(rqst[i].rq_pages);
                }
        }
}

/*
 * This function will initialize new_rq and encrypt the content.
 * The first entry, new_rq[0], only contains a single iov which contains
 * a smb2_transform_hdr and is pre-allocated by the caller.
 * This function then populates new_rq[1+] with the content from olq_rq[0+].
 *
 * The end result is an array of smb_rqst structures where the first structure
 * only contains a single iov for the transform header which we then can pass
 * to crypt_message().
 *
 * new_rq[0].rq_iov[0] :  smb2_transform_hdr pre-allocated by the caller
 * new_rq[1+].rq_iov[*] == old_rq[0+].rq_iov[*] : SMB2/3 requests
 */
static int
smb3_init_transform_rq(struct TCP_Server_Info *server, int num_rqst,
                       struct smb_rqst *new_rq, struct smb_rqst *old_rq)
{
        struct page **pages;
        struct smb2_transform_hdr *tr_hdr = new_rq[0].rq_iov[0].iov_base;
        unsigned int npages;
        unsigned int orig_len = 0;
        int i, j;
        int rc = -ENOMEM;

        for (i = 1; i < num_rqst; i++) {
                npages = old_rq[i - 1].rq_npages;
                pages = kmalloc_array(npages, sizeof(struct page *),
                                      GFP_KERNEL);
                if (!pages)
                        goto err_free;

                new_rq[i].rq_pages = pages;
                new_rq[i].rq_npages = npages;
                new_rq[i].rq_offset = old_rq[i - 1].rq_offset;
                new_rq[i].rq_pagesz = old_rq[i - 1].rq_pagesz;
                new_rq[i].rq_tailsz = old_rq[i - 1].rq_tailsz;
                new_rq[i].rq_iov = old_rq[i - 1].rq_iov;
                new_rq[i].rq_nvec = old_rq[i - 1].rq_nvec;

                orig_len += smb_rqst_len(server, &old_rq[i - 1]);

                for (j = 0; j < npages; j++) {
                        pages[j] = alloc_page(GFP_KERNEL|__GFP_HIGHMEM);
                        if (!pages[j])
                                goto err_free;
                }

                /* copy pages form the old */
                for (j = 0; j < npages; j++) {
                        char *dst, *src;
                        unsigned int offset, len;

                        rqst_page_get_length(&new_rq[i], j, &len, &offset);

                        dst = (char *) kmap(new_rq[i].rq_pages[j]) + offset;
                        src = (char *) kmap(old_rq[i - 1].rq_pages[j]) + offset;

                        memcpy(dst, src, len);
                        kunmap(new_rq[i].rq_pages[j]);
                        kunmap(old_rq[i - 1].rq_pages[j]);
                }
        }

        /* fill the 1st iov with a transform header */
        fill_transform_hdr(tr_hdr, orig_len, old_rq, server->cipher_type);

        rc = crypt_message(server, num_rqst, new_rq, 1);
        cifs_dbg(FYI, "Encrypt message returned %d\n", rc);
        if (rc)
                goto err_free;

        return rc;

err_free:
        smb3_free_compound_rqst(num_rqst - 1, &new_rq[1]);
        return rc;
}

static int
smb3_is_transform_hdr(void *buf)
{
        struct smb2_transform_hdr *trhdr = buf;

        return trhdr->ProtocolId == SMB2_TRANSFORM_PROTO_NUM;
}

static int
decrypt_raw_data(struct TCP_Server_Info *server, char *buf,
                 unsigned int buf_data_size, struct page **pages,
                 unsigned int npages, unsigned int page_data_size,
                 bool is_offloaded)
{
        struct kvec iov[2];
        struct smb_rqst rqst = {NULL};
        int rc;

        iov[0].iov_base = buf;
        iov[0].iov_len = sizeof(struct smb2_transform_hdr);
        iov[1].iov_base = buf + sizeof(struct smb2_transform_hdr);
        iov[1].iov_len = buf_data_size;

        rqst.rq_iov = iov;
        rqst.rq_nvec = 2;
        rqst.rq_pages = pages;
        rqst.rq_npages = npages;
        rqst.rq_pagesz = PAGE_SIZE;
        rqst.rq_tailsz = (page_data_size % PAGE_SIZE) ? : PAGE_SIZE;

        rc = crypt_message(server, 1, &rqst, 0);
        cifs_dbg(FYI, "Decrypt message returned %d\n", rc);

        if (rc)
                return rc;

        memmove(buf, iov[1].iov_base, buf_data_size);

        if (!is_offloaded)
                server->total_read = buf_data_size + page_data_size;

        return rc;
}

static int
read_data_into_pages(struct TCP_Server_Info *server, struct page **pages,
                     unsigned int npages, unsigned int len)
{
        int i;
        int length;

        for (i = 0; i < npages; i++) {
                struct page *page = pages[i];
                size_t n;

                n = len;
                if (len >= PAGE_SIZE) {
                        /* enough data to fill the page */
                        n = PAGE_SIZE;
                        len -= n;
                } else {
                        zero_user(page, len, PAGE_SIZE - len);
                        len = 0;
                }
                length = cifs_read_page_from_socket(server, page, 0, n);
                if (length < 0)
                        return length;
                server->total_read += length;
        }

        return 0;
}

static int
init_read_bvec(struct page **pages, unsigned int npages, unsigned int data_size,
               unsigned int cur_off, struct bio_vec **page_vec)
{
        struct bio_vec *bvec;
        int i;

        bvec = kcalloc(npages, sizeof(struct bio_vec), GFP_KERNEL);
        if (!bvec)
                return -ENOMEM;

        for (i = 0; i < npages; i++) {
                bvec[i].bv_page = pages[i];
                bvec[i].bv_offset = (i == 0) ? cur_off : 0;
                bvec[i].bv_len = min_t(unsigned int, PAGE_SIZE, data_size);
                data_size -= bvec[i].bv_len;
        }

        if (data_size != 0) {
                cifs_dbg(VFS, "%s: something went wrong\n", __func__);
                kfree(bvec);
                return -EIO;
        }

        *page_vec = bvec;
        return 0;
}

static int
handle_read_data(struct TCP_Server_Info *server, struct mid_q_entry *mid,
                 char *buf, unsigned int buf_len, struct page **pages,
                 unsigned int npages, unsigned int page_data_size,
                 bool is_offloaded)
{
        unsigned int data_offset;
        unsigned int data_len;
        unsigned int cur_off;
        unsigned int cur_page_idx;
        unsigned int pad_len;
        struct cifs_readdata *rdata = mid->callback_data;
        struct smb2_hdr *shdr = (struct smb2_hdr *)buf;
        struct bio_vec *bvec = NULL;
        struct iov_iter iter;
        struct kvec iov;
        int length;
        bool use_rdma_mr = false;

        if (shdr->Command != SMB2_READ) {
                cifs_server_dbg(VFS, "only big read responses are supported\n");
                return -ENOTSUPP;
        }

        if (server->ops->is_session_expired &&
            server->ops->is_session_expired(buf)) {
                if (!is_offloaded)
                        cifs_reconnect(server, true);
                return -1;
        }

        if (server->ops->is_status_pending &&
                        server->ops->is_status_pending(buf, server))
                return -1;

        /* set up first two iov to get credits */
        rdata->iov[0].iov_base = buf;
        rdata->iov[0].iov_len = 0;
        rdata->iov[1].iov_base = buf;
        rdata->iov[1].iov_len =
                min_t(unsigned int, buf_len, server->vals->read_rsp_size);
        cifs_dbg(FYI, "0: iov_base=%p iov_len=%zu\n",
                 rdata->iov[0].iov_base, rdata->iov[0].iov_len);
        cifs_dbg(FYI, "1: iov_base=%p iov_len=%zu\n",
                 rdata->iov[1].iov_base, rdata->iov[1].iov_len);

        rdata->result = server->ops->map_error(buf, true);
        if (rdata->result != 0) {
                cifs_dbg(FYI, "%s: server returned error %d\n",
                         __func__, rdata->result);
                /* normal error on read response */
                if (is_offloaded)
                        mid->mid_state = MID_RESPONSE_RECEIVED;
                else
                        dequeue_mid(mid, false);
                return 0;
        }

        data_offset = server->ops->read_data_offset(buf);
#ifdef CONFIG_CIFS_SMB_DIRECT
        use_rdma_mr = rdata->mr;
#endif
        data_len = server->ops->read_data_length(buf, use_rdma_mr);

        if (data_offset < server->vals->read_rsp_size) {
                /*
                 * win2k8 sometimes sends an offset of 0 when the read
                 * is beyond the EOF. Treat it as if the data starts just after
                 * the header.
                 */
                cifs_dbg(FYI, "%s: data offset (%u) inside read response header\n",
                         __func__, data_offset);
                data_offset = server->vals->read_rsp_size;
        } else if (data_offset > MAX_CIFS_SMALL_BUFFER_SIZE) {
                /* data_offset is beyond the end of smallbuf */
                cifs_dbg(FYI, "%s: data offset (%u) beyond end of smallbuf\n",
                         __func__, data_offset);
                rdata->result = -EIO;
                if (is_offloaded)
                        mid->mid_state = MID_RESPONSE_MALFORMED;
                else
                        dequeue_mid(mid, rdata->result);
                return 0;
        }

        pad_len = data_offset - server->vals->read_rsp_size;

        if (buf_len <= data_offset) {
                /* read response payload is in pages */
                cur_page_idx = pad_len / PAGE_SIZE;
                cur_off = pad_len % PAGE_SIZE;

                if (cur_page_idx != 0) {
                        /* data offset is beyond the 1st page of response */
                        cifs_dbg(FYI, "%s: data offset (%u) beyond 1st page of response\n",
                                 __func__, data_offset);
                        rdata->result = -EIO;
                        if (is_offloaded)
                                mid->mid_state = MID_RESPONSE_MALFORMED;
                        else
                                dequeue_mid(mid, rdata->result);
                        return 0;
                }

                if (data_len > page_data_size - pad_len) {
                        /* data_len is corrupt -- discard frame */
                        rdata->result = -EIO;
                        if (is_offloaded)
                                mid->mid_state = MID_RESPONSE_MALFORMED;
                        else
                                dequeue_mid(mid, rdata->result);
                        return 0;
                }

                rdata->result = init_read_bvec(pages, npages, page_data_size,
                                               cur_off, &bvec);
                if (rdata->result != 0) {
                        if (is_offloaded)
                                mid->mid_state = MID_RESPONSE_MALFORMED;
                        else
                                dequeue_mid(mid, rdata->result);
                        return 0;
                }

                iov_iter_bvec(&iter, WRITE, bvec, npages, data_len);
        } else if (buf_len >= data_offset + data_len) {
                /* read response payload is in buf */
                WARN_ONCE(npages > 0, "read data can be either in buf or in pages");
                iov.iov_base = buf + data_offset;
                iov.iov_len = data_len;
                iov_iter_kvec(&iter, WRITE, &iov, 1, data_len);
        } else {
                /* read response payload cannot be in both buf and pages */
                WARN_ONCE(1, "buf can not contain only a part of read data");
                rdata->result = -EIO;
                if (is_offloaded)
                        mid->mid_state = MID_RESPONSE_MALFORMED;
                else
                        dequeue_mid(mid, rdata->result);
                return 0;
        }

        length = rdata->copy_into_pages(server, rdata, &iter);

        kfree(bvec);

        if (length < 0)
                return length;

        if (is_offloaded)
                mid->mid_state = MID_RESPONSE_RECEIVED;
        else
                dequeue_mid(mid, false);
        return length;
}

struct smb2_decrypt_work {
        struct work_struct decrypt;
        struct TCP_Server_Info *server;
        struct page **ppages;
        char *buf;
        unsigned int npages;
        unsigned int len;
};


static void smb2_decrypt_offload(struct work_struct *work)
{
        struct smb2_decrypt_work *dw = container_of(work,
                                struct smb2_decrypt_work, decrypt);
        int i, rc;
        struct mid_q_entry *mid;

        rc = decrypt_raw_data(dw->server, dw->buf, dw->server->vals->read_rsp_size,
                              dw->ppages, dw->npages, dw->len, true);
        if (rc) {
                cifs_dbg(VFS, "error decrypting rc=%d\n", rc);
                goto free_pages;
        }

        dw->server->lstrp = jiffies;
        mid = smb2_find_dequeue_mid(dw->server, dw->buf);
        if (mid == NULL)
                cifs_dbg(FYI, "mid not found\n");
        else {
                mid->decrypted = true;
                rc = handle_read_data(dw->server, mid, dw->buf,
                                      dw->server->vals->read_rsp_size,
                                      dw->ppages, dw->npages, dw->len,
                                      true);
                if (rc >= 0) {
#ifdef CONFIG_CIFS_STATS2
                        mid->when_received = jiffies;
#endif
                        if (dw->server->ops->is_network_name_deleted)
                                dw->server->ops->is_network_name_deleted(dw->buf,
                                                                         dw->server);

                        mid->callback(mid);
                } else {
                        spin_lock(&dw->server->srv_lock);
                        if (dw->server->tcpStatus == CifsNeedReconnect) {
                                spin_lock(&dw->server->mid_lock);
                                mid->mid_state = MID_RETRY_NEEDED;
                                spin_unlock(&dw->server->mid_lock);
                                spin_unlock(&dw->server->srv_lock);
                                mid->callback(mid);
                        } else {
                                spin_lock(&dw->server->mid_lock);
                                mid->mid_state = MID_REQUEST_SUBMITTED;
                                mid->mid_flags &= ~(MID_DELETED);
                                list_add_tail(&mid->qhead,
                                        &dw->server->pending_mid_q);
                                spin_unlock(&dw->server->mid_lock);
                                spin_unlock(&dw->server->srv_lock);
                        }
                }
                release_mid(mid);
        }

free_pages:
        for (i = dw->npages-1; i >= 0; i--)
                put_page(dw->ppages[i]);

        kfree(dw->ppages);
        cifs_small_buf_release(dw->buf);
        kfree(dw);
}


static int
receive_encrypted_read(struct TCP_Server_Info *server, struct mid_q_entry **mid,
                       int *num_mids)
{
        char *buf = server->smallbuf;
        struct smb2_transform_hdr *tr_hdr = (struct smb2_transform_hdr *)buf;
        unsigned int npages;
        struct page **pages;
        unsigned int len;
        unsigned int buflen = server->pdu_size;
        int rc;
        int i = 0;
        struct smb2_decrypt_work *dw;

        *num_mids = 1;
        len = min_t(unsigned int, buflen, server->vals->read_rsp_size +
                sizeof(struct smb2_transform_hdr)) - HEADER_SIZE(server) + 1;

        rc = cifs_read_from_socket(server, buf + HEADER_SIZE(server) - 1, len);
        if (rc < 0)
                return rc;
        server->total_read += rc;

        len = le32_to_cpu(tr_hdr->OriginalMessageSize) -
                server->vals->read_rsp_size;
        npages = DIV_ROUND_UP(len, PAGE_SIZE);

        pages = kmalloc_array(npages, sizeof(struct page *), GFP_KERNEL);
        if (!pages) {
                rc = -ENOMEM;
                goto discard_data;
        }

        for (; i < npages; i++) {
                pages[i] = alloc_page(GFP_KERNEL|__GFP_HIGHMEM);
                if (!pages[i]) {
                        rc = -ENOMEM;
                        goto discard_data;
                }
        }

        /* read read data into pages */
        rc = read_data_into_pages(server, pages, npages, len);
        if (rc)
                goto free_pages;

        rc = cifs_discard_remaining_data(server);
        if (rc)
                goto free_pages;

        /*
         * For large reads, offload to different thread for better performance,
         * use more cores decrypting which can be expensive
         */

        if ((server->min_offload) && (server->in_flight > 1) &&
            (server->pdu_size >= server->min_offload)) {
                dw = kmalloc(sizeof(struct smb2_decrypt_work), GFP_KERNEL);
                if (dw == NULL)
                        goto non_offloaded_decrypt;

                dw->buf = server->smallbuf;
                server->smallbuf = (char *)cifs_small_buf_get();

                INIT_WORK(&dw->decrypt, smb2_decrypt_offload);

                dw->npages = npages;
                dw->server = server;
                dw->ppages = pages;
                dw->len = len;
                queue_work(decrypt_wq, &dw->decrypt);
                *num_mids = 0; /* worker thread takes care of finding mid */
                return -1;
        }

non_offloaded_decrypt:
        rc = decrypt_raw_data(server, buf, server->vals->read_rsp_size,
                              pages, npages, len, false);
        if (rc)
                goto free_pages;

        *mid = smb2_find_mid(server, buf);
        if (*mid == NULL)
                cifs_dbg(FYI, "mid not found\n");
        else {
                cifs_dbg(FYI, "mid found\n");
                (*mid)->decrypted = true;
                rc = handle_read_data(server, *mid, buf,
                                      server->vals->read_rsp_size,
                                      pages, npages, len, false);
                if (rc >= 0) {
                        if (server->ops->is_network_name_deleted) {
                                server->ops->is_network_name_deleted(buf,
                                                                server);
                        }
                }
        }

free_pages:
        for (i = i - 1; i >= 0; i--)
                put_page(pages[i]);
        kfree(pages);
        return rc;
discard_data:
        cifs_discard_remaining_data(server);
        goto free_pages;
}

static int
receive_encrypted_standard(struct TCP_Server_Info *server,
                           struct mid_q_entry **mids, char **bufs,
                           int *num_mids)
{
        int ret, length;
        char *buf = server->smallbuf;
        struct smb2_hdr *shdr;
        unsigned int pdu_length = server->pdu_size;
        unsigned int buf_size;
        struct mid_q_entry *mid_entry;
        int next_is_large;
        char *next_buffer = NULL;

        *num_mids = 0;

        /* switch to large buffer if too big for a small one */
        if (pdu_length > MAX_CIFS_SMALL_BUFFER_SIZE) {
                server->large_buf = true;
                memcpy(server->bigbuf, buf, server->total_read);
                buf = server->bigbuf;
        }

        /* now read the rest */
        length = cifs_read_from_socket(server, buf + HEADER_SIZE(server) - 1,
                                pdu_length - HEADER_SIZE(server) + 1);
        if (length < 0)
                return length;
        server->total_read += length;

        buf_size = pdu_length - sizeof(struct smb2_transform_hdr);
        length = decrypt_raw_data(server, buf, buf_size, NULL, 0, 0, false);
        if (length)
                return length;

        next_is_large = server->large_buf;
one_more:
        shdr = (struct smb2_hdr *)buf;
        if (shdr->NextCommand) {
                if (next_is_large)
                        next_buffer = (char *)cifs_buf_get();
                else
                        next_buffer = (char *)cifs_small_buf_get();
                memcpy(next_buffer,
                       buf + le32_to_cpu(shdr->NextCommand),
                       pdu_length - le32_to_cpu(shdr->NextCommand));
        }

        mid_entry = smb2_find_mid(server, buf);
        if (mid_entry == NULL)
                cifs_dbg(FYI, "mid not found\n");
        else {
                cifs_dbg(FYI, "mid found\n");
                mid_entry->decrypted = true;
                mid_entry->resp_buf_size = server->pdu_size;
        }

        if (*num_mids >= MAX_COMPOUND) {
                cifs_server_dbg(VFS, "too many PDUs in compound\n");
                return -1;
        }
        bufs[*num_mids] = buf;
        mids[(*num_mids)++] = mid_entry;

        if (mid_entry && mid_entry->handle)
                ret = mid_entry->handle(server, mid_entry);
        else
                ret = cifs_handle_standard(server, mid_entry);

        if (ret == 0 && shdr->NextCommand) {
                pdu_length -= le32_to_cpu(shdr->NextCommand);
                server->large_buf = next_is_large;
                if (next_is_large)
                        server->bigbuf = buf = next_buffer;
                else
                        server->smallbuf = buf = next_buffer;
                goto one_more;
        } else if (ret != 0) {
                /*
                 * ret != 0 here means that we didn't get to handle_mid() thus
                 * server->smallbuf and server->bigbuf are still valid. We need
                 * to free next_buffer because it is not going to be used
                 * anywhere.
                 */
                if (next_is_large)
                        free_rsp_buf(CIFS_LARGE_BUFFER, next_buffer);
                else
                        free_rsp_buf(CIFS_SMALL_BUFFER, next_buffer);
        }

        return ret;
}

static int
smb3_receive_transform(struct TCP_Server_Info *server,
                       struct mid_q_entry **mids, char **bufs, int *num_mids)
{
        char *buf = server->smallbuf;
        unsigned int pdu_length = server->pdu_size;
        struct smb2_transform_hdr *tr_hdr = (struct smb2_transform_hdr *)buf;
        unsigned int orig_len = le32_to_cpu(tr_hdr->OriginalMessageSize);

        if (pdu_length < sizeof(struct smb2_transform_hdr) +
                                                sizeof(struct smb2_hdr)) {
                cifs_server_dbg(VFS, "Transform message is too small (%u)\n",
                         pdu_length);
                cifs_reconnect(server, true);
                return -ECONNABORTED;
        }

        if (pdu_length < orig_len + sizeof(struct smb2_transform_hdr)) {
                cifs_server_dbg(VFS, "Transform message is broken\n");
                cifs_reconnect(server, true);
                return -ECONNABORTED;
        }

        /* TODO: add support for compounds containing READ. */
        if (pdu_length > CIFSMaxBufSize + MAX_HEADER_SIZE(server)) {
                return receive_encrypted_read(server, &mids[0], num_mids);
        }

        return receive_encrypted_standard(server, mids, bufs, num_mids);
}

int
smb3_handle_read_data(struct TCP_Server_Info *server, struct mid_q_entry *mid)
{
        char *buf = server->large_buf ? server->bigbuf : server->smallbuf;

        return handle_read_data(server, mid, buf, server->pdu_size,
                                NULL, 0, 0, false);
}

static int
smb2_next_header(char *buf)
{
        struct smb2_hdr *hdr = (struct smb2_hdr *)buf;
        struct smb2_transform_hdr *t_hdr = (struct smb2_transform_hdr *)buf;

        if (hdr->ProtocolId == SMB2_TRANSFORM_PROTO_NUM)
                return sizeof(struct smb2_transform_hdr) +
                  le32_to_cpu(t_hdr->OriginalMessageSize);

        return le32_to_cpu(hdr->NextCommand);
}

static int
smb2_make_node(unsigned int xid, struct inode *inode,
               struct dentry *dentry, struct cifs_tcon *tcon,
               const char *full_path, umode_t mode, dev_t dev)
{
        struct cifs_sb_info *cifs_sb = CIFS_SB(inode->i_sb);
        int rc = -EPERM;
        FILE_ALL_INFO *buf = NULL;
        struct cifs_io_parms io_parms = {0};
        __u32 oplock = 0;
        struct cifs_fid fid;
        struct cifs_open_parms oparms;
        unsigned int bytes_written;
        struct win_dev *pdev;
        struct kvec iov[2];

        /*
         * Check if mounted with mount parm 'sfu' mount parm.
         * SFU emulation should work with all servers, but only
         * supports block and char device (no socket & fifo),
         * and was used by default in earlier versions of Windows
         */
        if (!(cifs_sb->mnt_cifs_flags & CIFS_MOUNT_UNX_EMUL))
                goto out;

        /*
         * TODO: Add ability to create instead via reparse point. Windows (e.g.
         * their current NFS server) uses this approach to expose special files
         * over SMB2/SMB3 and Samba will do this with SMB3.1.1 POSIX Extensions
         */

        if (!S_ISCHR(mode) && !S_ISBLK(mode))
                goto out;

        cifs_dbg(FYI, "sfu compat create special file\n");

        buf = kmalloc(sizeof(FILE_ALL_INFO), GFP_KERNEL);
        if (buf == NULL) {
                rc = -ENOMEM;
                goto out;
        }

        oparms.tcon = tcon;
        oparms.cifs_sb = cifs_sb;
        oparms.desired_access = GENERIC_WRITE;
        oparms.create_options = cifs_create_options(cifs_sb, CREATE_NOT_DIR |
                                                    CREATE_OPTION_SPECIAL);
        oparms.disposition = FILE_CREATE;
        oparms.path = full_path;
        oparms.fid = &fid;
        oparms.reconnect = false;

        if (tcon->ses->server->oplocks)
                oplock = REQ_OPLOCK;
        else
                oplock = 0;
        rc = tcon->ses->server->ops->open(xid, &oparms, &oplock, buf);
        if (rc)
                goto out;

        /*
         * BB Do not bother to decode buf since no local inode yet to put
         * timestamps in, but we can reuse it safely.
         */

        pdev = (struct win_dev *)buf;
        io_parms.pid = current->tgid;
        io_parms.tcon = tcon;
        io_parms.offset = 0;
        io_parms.length = sizeof(struct win_dev);
        iov[1].iov_base = buf;
        iov[1].iov_len = sizeof(struct win_dev);
        if (S_ISCHR(mode)) {
                memcpy(pdev->type, "IntxCHR", 8);
                pdev->major = cpu_to_le64(MAJOR(dev));
                pdev->minor = cpu_to_le64(MINOR(dev));
                rc = tcon->ses->server->ops->sync_write(xid, &fid, &io_parms,
                                                        &bytes_written, iov, 1);
        } else if (S_ISBLK(mode)) {
                memcpy(pdev->type, "IntxBLK", 8);
                pdev->major = cpu_to_le64(MAJOR(dev));
                pdev->minor = cpu_to_le64(MINOR(dev));
                rc = tcon->ses->server->ops->sync_write(xid, &fid, &io_parms,
                                                        &bytes_written, iov, 1);
        }
        tcon->ses->server->ops->close(xid, tcon, &fid);
        d_drop(dentry);

        /* FIXME: add code here to set EAs */
out:
        kfree(buf);
        return rc;
}

#ifdef CONFIG_CIFS_ALLOW_INSECURE_LEGACY
struct smb_version_operations smb20_operations = {
        .compare_fids = smb2_compare_fids,
        .setup_request = smb2_setup_request,
        .setup_async_request = smb2_setup_async_request,
        .check_receive = smb2_check_receive,
        .add_credits = smb2_add_credits,
        .set_credits = smb2_set_credits,
        .get_credits_field = smb2_get_credits_field,
        .get_credits = smb2_get_credits,
        .wait_mtu_credits = cifs_wait_mtu_credits,
        .get_next_mid = smb2_get_next_mid,
        .revert_current_mid = smb2_revert_current_mid,
        .read_data_offset = smb2_read_data_offset,
        .read_data_length = smb2_read_data_length,
        .map_error = map_smb2_to_linux_error,
        .find_mid = smb2_find_mid,
        .check_message = smb2_check_message,
        .dump_detail = smb2_dump_detail,
        .clear_stats = smb2_clear_stats,
        .print_stats = smb2_print_stats,
        .is_oplock_break = smb2_is_valid_oplock_break,
        .handle_cancelled_mid = smb2_handle_cancelled_mid,
        .downgrade_oplock = smb2_downgrade_oplock,
        .need_neg = smb2_need_neg,
        .negotiate = smb2_negotiate,
        .negotiate_wsize = smb2_negotiate_wsize,
        .negotiate_rsize = smb2_negotiate_rsize,
        .sess_setup = SMB2_sess_setup,
        .logoff = SMB2_logoff,
        .tree_connect = SMB2_tcon,
        .tree_disconnect = SMB2_tdis,
        .qfs_tcon = smb2_qfs_tcon,
        .is_path_accessible = smb2_is_path_accessible,
        .can_echo = smb2_can_echo,
        .echo = SMB2_echo,
        .query_path_info = smb2_query_path_info,
        .get_srv_inum = smb2_get_srv_inum,
        .query_file_info = smb2_query_file_info,
        .set_path_size = smb2_set_path_size,
        .set_file_size = smb2_set_file_size,
        .set_file_info = smb2_set_file_info,
        .set_compression = smb2_set_compression,
        .mkdir = smb2_mkdir,
        .mkdir_setinfo = smb2_mkdir_setinfo,
        .rmdir = smb2_rmdir,
        .unlink = smb2_unlink,
        .rename = smb2_rename_path,
        .create_hardlink = smb2_create_hardlink,
        .query_symlink = smb2_query_symlink,
        .query_mf_symlink = smb3_query_mf_symlink,
        .create_mf_symlink = smb3_create_mf_symlink,
        .open = smb2_open_file,
        .set_fid = smb2_set_fid,
        .close = smb2_close_file,
        .flush = smb2_flush_file,
        .async_readv = smb2_async_readv,
        .async_writev = smb2_async_writev,
        .sync_read = smb2_sync_read,
        .sync_write = smb2_sync_write,
        .query_dir_first = smb2_query_dir_first,
        .query_dir_next = smb2_query_dir_next,
        .close_dir = smb2_close_dir,
        .calc_smb_size = smb2_calc_size,
        .is_status_pending = smb2_is_status_pending,
        .is_session_expired = smb2_is_session_expired,
        .oplock_response = smb2_oplock_response,
        .queryfs = smb2_queryfs,
        .mand_lock = smb2_mand_lock,
        .mand_unlock_range = smb2_unlock_range,
        .push_mand_locks = smb2_push_mandatory_locks,
        .get_lease_key = smb2_get_lease_key,
        .set_lease_key = smb2_set_lease_key,
        .new_lease_key = smb2_new_lease_key,
        .calc_signature = smb2_calc_signature,
        .is_read_op = smb2_is_read_op,
        .set_oplock_level = smb2_set_oplock_level,
        .create_lease_buf = smb2_create_lease_buf,
        .parse_lease_buf = smb2_parse_lease_buf,
        .copychunk_range = smb2_copychunk_range,
        .wp_retry_size = smb2_wp_retry_size,
        .dir_needs_close = smb2_dir_needs_close,
        .get_dfs_refer = smb2_get_dfs_refer,
        .select_sectype = smb2_select_sectype,
#ifdef CONFIG_CIFS_XATTR
        .query_all_EAs = smb2_query_eas,
        .set_EA = smb2_set_ea,
#endif /* CIFS_XATTR */
        .get_acl = get_smb2_acl,
        .get_acl_by_fid = get_smb2_acl_by_fid,
        .set_acl = set_smb2_acl,
        .next_header = smb2_next_header,
        .ioctl_query_info = smb2_ioctl_query_info,
        .make_node = smb2_make_node,
        .fiemap = smb3_fiemap,
        .llseek = smb3_llseek,
        .is_status_io_timeout = smb2_is_status_io_timeout,
        .is_network_name_deleted = smb2_is_network_name_deleted,
};
#endif /* CIFS_ALLOW_INSECURE_LEGACY */

struct smb_version_operations smb21_operations = {
        .compare_fids = smb2_compare_fids,
        .setup_request = smb2_setup_request,
        .setup_async_request = smb2_setup_async_request,
        .check_receive = smb2_check_receive,
        .add_credits = smb2_add_credits,
        .set_credits = smb2_set_credits,
        .get_credits_field = smb2_get_credits_field,
        .get_credits = smb2_get_credits,
        .wait_mtu_credits = smb2_wait_mtu_credits,
        .adjust_credits = smb2_adjust_credits,
        .get_next_mid = smb2_get_next_mid,
        .revert_current_mid = smb2_revert_current_mid,
        .read_data_offset = smb2_read_data_offset,
        .read_data_length = smb2_read_data_length,
        .map_error = map_smb2_to_linux_error,
        .find_mid = smb2_find_mid,
        .check_message = smb2_check_message,
        .dump_detail = smb2_dump_detail,
        .clear_stats = smb2_clear_stats,
        .print_stats = smb2_print_stats,
        .is_oplock_break = smb2_is_valid_oplock_break,
        .handle_cancelled_mid = smb2_handle_cancelled_mid,
        .downgrade_oplock = smb2_downgrade_oplock,
        .need_neg = smb2_need_neg,
        .negotiate = smb2_negotiate,
        .negotiate_wsize = smb2_negotiate_wsize,
        .negotiate_rsize = smb2_negotiate_rsize,
        .sess_setup = SMB2_sess_setup,
        .logoff = SMB2_logoff,
        .tree_connect = SMB2_tcon,
        .tree_disconnect = SMB2_tdis,
        .qfs_tcon = smb2_qfs_tcon,
        .is_path_accessible = smb2_is_path_accessible,
        .can_echo = smb2_can_echo,
        .echo = SMB2_echo,
        .query_path_info = smb2_query_path_info,
        .get_srv_inum = smb2_get_srv_inum,
        .query_file_info = smb2_query_file_info,
        .set_path_size = smb2_set_path_size,
        .set_file_size = smb2_set_file_size,
        .set_file_info = smb2_set_file_info,
        .set_compression = smb2_set_compression,
        .mkdir = smb2_mkdir,
        .mkdir_setinfo = smb2_mkdir_setinfo,
        .rmdir = smb2_rmdir,
        .unlink = smb2_unlink,
        .rename = smb2_rename_path,
        .create_hardlink = smb2_create_hardlink,
        .query_symlink = smb2_query_symlink,
        .query_mf_symlink = smb3_query_mf_symlink,
        .create_mf_symlink = smb3_create_mf_symlink,
        .open = smb2_open_file,
        .set_fid = smb2_set_fid,
        .close = smb2_close_file,
        .flush = smb2_flush_file,
        .async_readv = smb2_async_readv,
        .async_writev = smb2_async_writev,
        .sync_read = smb2_sync_read,
        .sync_write = smb2_sync_write,
        .query_dir_first = smb2_query_dir_first,
        .query_dir_next = smb2_query_dir_next,
        .close_dir = smb2_close_dir,
        .calc_smb_size = smb2_calc_size,
        .is_status_pending = smb2_is_status_pending,
        .is_session_expired = smb2_is_session_expired,
        .oplock_response = smb2_oplock_response,
        .queryfs = smb2_queryfs,
        .mand_lock = smb2_mand_lock,
        .mand_unlock_range = smb2_unlock_range,
        .push_mand_locks = smb2_push_mandatory_locks,
        .get_lease_key = smb2_get_lease_key,
        .set_lease_key = smb2_set_lease_key,
        .new_lease_key = smb2_new_lease_key,
        .calc_signature = smb2_calc_signature,
        .is_read_op = smb21_is_read_op,
        .set_oplock_level = smb21_set_oplock_level,
        .create_lease_buf = smb2_create_lease_buf,
        .parse_lease_buf = smb2_parse_lease_buf,
        .copychunk_range = smb2_copychunk_range,
        .wp_retry_size = smb2_wp_retry_size,
        .dir_needs_close = smb2_dir_needs_close,
        .enum_snapshots = smb3_enum_snapshots,
        .notify = smb3_notify,
        .get_dfs_refer = smb2_get_dfs_refer,
        .select_sectype = smb2_select_sectype,
#ifdef CONFIG_CIFS_XATTR
        .query_all_EAs = smb2_query_eas,
        .set_EA = smb2_set_ea,
#endif /* CIFS_XATTR */
        .get_acl = get_smb2_acl,
        .get_acl_by_fid = get_smb2_acl_by_fid,
        .set_acl = set_smb2_acl,
        .next_header = smb2_next_header,
        .ioctl_query_info = smb2_ioctl_query_info,
        .make_node = smb2_make_node,
        .fiemap = smb3_fiemap,
        .llseek = smb3_llseek,
        .is_status_io_timeout = smb2_is_status_io_timeout,
        .is_network_name_deleted = smb2_is_network_name_deleted,
};

struct smb_version_operations smb30_operations = {
        .compare_fids = smb2_compare_fids,
        .setup_request = smb2_setup_request,
        .setup_async_request = smb2_setup_async_request,
        .check_receive = smb2_check_receive,
        .add_credits = smb2_add_credits,
        .set_credits = smb2_set_credits,
        .get_credits_field = smb2_get_credits_field,
        .get_credits = smb2_get_credits,
        .wait_mtu_credits = smb2_wait_mtu_credits,
        .adjust_credits = smb2_adjust_credits,
        .get_next_mid = smb2_get_next_mid,
        .revert_current_mid = smb2_revert_current_mid,
        .read_data_offset = smb2_read_data_offset,
        .read_data_length = smb2_read_data_length,
        .map_error = map_smb2_to_linux_error,
        .find_mid = smb2_find_mid,
        .check_message = smb2_check_message,
        .dump_detail = smb2_dump_detail,
        .clear_stats = smb2_clear_stats,
        .print_stats = smb2_print_stats,
        .dump_share_caps = smb2_dump_share_caps,
        .is_oplock_break = smb2_is_valid_oplock_break,
        .handle_cancelled_mid = smb2_handle_cancelled_mid,
        .downgrade_oplock = smb3_downgrade_oplock,
        .need_neg = smb2_need_neg,
        .negotiate = smb2_negotiate,
        .negotiate_wsize = smb3_negotiate_wsize,
        .negotiate_rsize = smb3_negotiate_rsize,
        .sess_setup = SMB2_sess_setup,
        .logoff = SMB2_logoff,
        .tree_connect = SMB2_tcon,
        .tree_disconnect = SMB2_tdis,
        .qfs_tcon = smb3_qfs_tcon,
        .is_path_accessible = smb2_is_path_accessible,
        .can_echo = smb2_can_echo,
        .echo = SMB2_echo,
        .query_path_info = smb2_query_path_info,
        /* WSL tags introduced long after smb2.1, enable for SMB3, 3.11 only */
        .query_reparse_tag = smb2_query_reparse_tag,
        .get_srv_inum = smb2_get_srv_inum,
        .query_file_info = smb2_query_file_info,
        .set_path_size = smb2_set_path_size,
        .set_file_size = smb2_set_file_size,
        .set_file_info = smb2_set_file_info,
        .set_compression = smb2_set_compression,
        .mkdir = smb2_mkdir,
        .mkdir_setinfo = smb2_mkdir_setinfo,
        .rmdir = smb2_rmdir,
        .unlink = smb2_unlink,
        .rename = smb2_rename_path,
        .create_hardlink = smb2_create_hardlink,
        .query_symlink = smb2_query_symlink,
        .query_mf_symlink = smb3_query_mf_symlink,
        .create_mf_symlink = smb3_create_mf_symlink,
        .open = smb2_open_file,
        .set_fid = smb2_set_fid,
        .close = smb2_close_file,
        .close_getattr = smb2_close_getattr,
        .flush = smb2_flush_file,
        .async_readv = smb2_async_readv,
        .async_writev = smb2_async_writev,
        .sync_read = smb2_sync_read,
        .sync_write = smb2_sync_write,
        .query_dir_first = smb2_query_dir_first,
        .query_dir_next = smb2_query_dir_next,
        .close_dir = smb2_close_dir,
        .calc_smb_size = smb2_calc_size,
        .is_status_pending = smb2_is_status_pending,
        .is_session_expired = smb2_is_session_expired,
        .oplock_response = smb2_oplock_response,
        .queryfs = smb2_queryfs,
        .mand_lock = smb2_mand_lock,
        .mand_unlock_range = smb2_unlock_range,
        .push_mand_locks = smb2_push_mandatory_locks,
        .get_lease_key = smb2_get_lease_key,
        .set_lease_key = smb2_set_lease_key,
        .new_lease_key = smb2_new_lease_key,
        .generate_signingkey = generate_smb30signingkey,
        .calc_signature = smb3_calc_signature,
        .set_integrity  = smb3_set_integrity,
        .is_read_op = smb21_is_read_op,
        .set_oplock_level = smb3_set_oplock_level,
        .create_lease_buf = smb3_create_lease_buf,
        .parse_lease_buf = smb3_parse_lease_buf,
        .copychunk_range = smb2_copychunk_range,
        .duplicate_extents = smb2_duplicate_extents,
        .validate_negotiate = smb3_validate_negotiate,
        .wp_retry_size = smb2_wp_retry_size,
        .dir_needs_close = smb2_dir_needs_close,
        .fallocate = smb3_fallocate,
        .enum_snapshots = smb3_enum_snapshots,
        .notify = smb3_notify,
        .init_transform_rq = smb3_init_transform_rq,
        .is_transform_hdr = smb3_is_transform_hdr,
        .receive_transform = smb3_receive_transform,
        .get_dfs_refer = smb2_get_dfs_refer,
        .select_sectype = smb2_select_sectype,
#ifdef CONFIG_CIFS_XATTR
        .query_all_EAs = smb2_query_eas,
        .set_EA = smb2_set_ea,
#endif /* CIFS_XATTR */
        .get_acl = get_smb2_acl,
        .get_acl_by_fid = get_smb2_acl_by_fid,
        .set_acl = set_smb2_acl,
        .next_header = smb2_next_header,
        .ioctl_query_info = smb2_ioctl_query_info,
        .make_node = smb2_make_node,
        .fiemap = smb3_fiemap,
        .llseek = smb3_llseek,
        .is_status_io_timeout = smb2_is_status_io_timeout,
        .is_network_name_deleted = smb2_is_network_name_deleted,
};

struct smb_version_operations smb311_operations = {
        .compare_fids = smb2_compare_fids,
        .setup_request = smb2_setup_request,
        .setup_async_request = smb2_setup_async_request,
        .check_receive = smb2_check_receive,
        .add_credits = smb2_add_credits,
        .set_credits = smb2_set_credits,
        .get_credits_field = smb2_get_credits_field,
        .get_credits = smb2_get_credits,
        .wait_mtu_credits = smb2_wait_mtu_credits,
        .adjust_credits = smb2_adjust_credits,
        .get_next_mid = smb2_get_next_mid,
        .revert_current_mid = smb2_revert_current_mid,
        .read_data_offset = smb2_read_data_offset,
        .read_data_length = smb2_read_data_length,
        .map_error = map_smb2_to_linux_error,
        .find_mid = smb2_find_mid,
        .check_message = smb2_check_message,
        .dump_detail = smb2_dump_detail,
        .clear_stats = smb2_clear_stats,
        .print_stats = smb2_print_stats,
        .dump_share_caps = smb2_dump_share_caps,
        .is_oplock_break = smb2_is_valid_oplock_break,
        .handle_cancelled_mid = smb2_handle_cancelled_mid,
        .downgrade_oplock = smb3_downgrade_oplock,
        .need_neg = smb2_need_neg,
        .negotiate = smb2_negotiate,
        .negotiate_wsize = smb3_negotiate_wsize,
        .negotiate_rsize = smb3_negotiate_rsize,
        .sess_setup = SMB2_sess_setup,
        .logoff = SMB2_logoff,
        .tree_connect = SMB2_tcon,
        .tree_disconnect = SMB2_tdis,
        .qfs_tcon = smb3_qfs_tcon,
        .is_path_accessible = smb2_is_path_accessible,
        .can_echo = smb2_can_echo,
        .echo = SMB2_echo,
        .query_path_info = smb2_query_path_info,
        .query_reparse_tag = smb2_query_reparse_tag,
        .get_srv_inum = smb2_get_srv_inum,
        .query_file_info = smb2_query_file_info,
        .set_path_size = smb2_set_path_size,
        .set_file_size = smb2_set_file_size,
        .set_file_info = smb2_set_file_info,
        .set_compression = smb2_set_compression,
        .mkdir = smb2_mkdir,
        .mkdir_setinfo = smb2_mkdir_setinfo,
        .posix_mkdir = smb311_posix_mkdir,
        .rmdir = smb2_rmdir,
        .unlink = smb2_unlink,
        .rename = smb2_rename_path,
        .create_hardlink = smb2_create_hardlink,
        .query_symlink = smb2_query_symlink,
        .query_mf_symlink = smb3_query_mf_symlink,
        .create_mf_symlink = smb3_create_mf_symlink,
        .open = smb2_open_file,
        .set_fid = smb2_set_fid,
        .close = smb2_close_file,
        .close_getattr = smb2_close_getattr,
        .flush = smb2_flush_file,
        .async_readv = smb2_async_readv,
        .async_writev = smb2_async_writev,
        .sync_read = smb2_sync_read,
        .sync_write = smb2_sync_write,
        .query_dir_first = smb2_query_dir_first,
        .query_dir_next = smb2_query_dir_next,
        .close_dir = smb2_close_dir,
        .calc_smb_size = smb2_calc_size,
        .is_status_pending = smb2_is_status_pending,
        .is_session_expired = smb2_is_session_expired,
        .oplock_response = smb2_oplock_response,
        .queryfs = smb311_queryfs,
        .mand_lock = smb2_mand_lock,
        .mand_unlock_range = smb2_unlock_range,
        .push_mand_locks = smb2_push_mandatory_locks,
        .get_lease_key = smb2_get_lease_key,
        .set_lease_key = smb2_set_lease_key,
        .new_lease_key = smb2_new_lease_key,
        .generate_signingkey = generate_smb311signingkey,
        .calc_signature = smb3_calc_signature,
        .set_integrity  = smb3_set_integrity,
        .is_read_op = smb21_is_read_op,
        .set_oplock_level = smb3_set_oplock_level,
        .create_lease_buf = smb3_create_lease_buf,
        .parse_lease_buf = smb3_parse_lease_buf,
        .copychunk_range = smb2_copychunk_range,
        .duplicate_extents = smb2_duplicate_extents,
/*      .validate_negotiate = smb3_validate_negotiate, */ /* not used in 3.11 */
        .wp_retry_size = smb2_wp_retry_size,
        .dir_needs_close = smb2_dir_needs_close,
        .fallocate = smb3_fallocate,
        .enum_snapshots = smb3_enum_snapshots,
        .notify = smb3_notify,
        .init_transform_rq = smb3_init_transform_rq,
        .is_transform_hdr = smb3_is_transform_hdr,
        .receive_transform = smb3_receive_transform,
        .get_dfs_refer = smb2_get_dfs_refer,
        .select_sectype = smb2_select_sectype,
#ifdef CONFIG_CIFS_XATTR
        .query_all_EAs = smb2_query_eas,
        .set_EA = smb2_set_ea,
#endif /* CIFS_XATTR */
        .get_acl = get_smb2_acl,
        .get_acl_by_fid = get_smb2_acl_by_fid,
        .set_acl = set_smb2_acl,
        .next_header = smb2_next_header,
        .ioctl_query_info = smb2_ioctl_query_info,
        .make_node = smb2_make_node,
        .fiemap = smb3_fiemap,
        .llseek = smb3_llseek,
        .is_status_io_timeout = smb2_is_status_io_timeout,
        .is_network_name_deleted = smb2_is_network_name_deleted,
};

#ifdef CONFIG_CIFS_ALLOW_INSECURE_LEGACY
struct smb_version_values smb20_values = {
        .version_string = SMB20_VERSION_STRING,
        .protocol_id = SMB20_PROT_ID,
        .req_capabilities = 0, /* MBZ */
        .large_lock_type = 0,
        .exclusive_lock_type = SMB2_LOCKFLAG_EXCLUSIVE,
        .shared_lock_type = SMB2_LOCKFLAG_SHARED,
        .unlock_lock_type = SMB2_LOCKFLAG_UNLOCK,
        .header_size = sizeof(struct smb2_hdr),
        .header_preamble_size = 0,
        .max_header_size = MAX_SMB2_HDR_SIZE,
        .read_rsp_size = sizeof(struct smb2_read_rsp) - 1,
        .lock_cmd = SMB2_LOCK,
        .cap_unix = 0,
        .cap_nt_find = SMB2_NT_FIND,
        .cap_large_files = SMB2_LARGE_FILES,
        .signing_enabled = SMB2_NEGOTIATE_SIGNING_ENABLED | SMB2_NEGOTIATE_SIGNING_REQUIRED,
        .signing_required = SMB2_NEGOTIATE_SIGNING_REQUIRED,
        .create_lease_size = sizeof(struct create_lease),
};
#endif /* ALLOW_INSECURE_LEGACY */

struct smb_version_values smb21_values = {
        .version_string = SMB21_VERSION_STRING,
        .protocol_id = SMB21_PROT_ID,
        .req_capabilities = 0, /* MBZ on negotiate req until SMB3 dialect */
        .large_lock_type = 0,
        .exclusive_lock_type = SMB2_LOCKFLAG_EXCLUSIVE,
        .shared_lock_type = SMB2_LOCKFLAG_SHARED,
        .unlock_lock_type = SMB2_LOCKFLAG_UNLOCK,
        .header_size = sizeof(struct smb2_hdr),
        .header_preamble_size = 0,
        .max_header_size = MAX_SMB2_HDR_SIZE,
        .read_rsp_size = sizeof(struct smb2_read_rsp) - 1,
        .lock_cmd = SMB2_LOCK,
        .cap_unix = 0,
        .cap_nt_find = SMB2_NT_FIND,
        .cap_large_files = SMB2_LARGE_FILES,
        .signing_enabled = SMB2_NEGOTIATE_SIGNING_ENABLED | SMB2_NEGOTIATE_SIGNING_REQUIRED,
        .signing_required = SMB2_NEGOTIATE_SIGNING_REQUIRED,
        .create_lease_size = sizeof(struct create_lease),
};

struct smb_version_values smb3any_values = {
        .version_string = SMB3ANY_VERSION_STRING,
        .protocol_id = SMB302_PROT_ID, /* doesn't matter, send protocol array */
        .req_capabilities = SMB2_GLOBAL_CAP_DFS | SMB2_GLOBAL_CAP_LEASING | SMB2_GLOBAL_CAP_LARGE_MTU | SMB2_GLOBAL_CAP_PERSISTENT_HANDLES | SMB2_GLOBAL_CAP_ENCRYPTION | SMB2_GLOBAL_CAP_DIRECTORY_LEASING,
        .large_lock_type = 0,
        .exclusive_lock_type = SMB2_LOCKFLAG_EXCLUSIVE,
        .shared_lock_type = SMB2_LOCKFLAG_SHARED,
        .unlock_lock_type = SMB2_LOCKFLAG_UNLOCK,
        .header_size = sizeof(struct smb2_hdr),
        .header_preamble_size = 0,
        .max_header_size = MAX_SMB2_HDR_SIZE,
        .read_rsp_size = sizeof(struct smb2_read_rsp) - 1,
        .lock_cmd = SMB2_LOCK,
        .cap_unix = 0,
        .cap_nt_find = SMB2_NT_FIND,
        .cap_large_files = SMB2_LARGE_FILES,
        .signing_enabled = SMB2_NEGOTIATE_SIGNING_ENABLED | SMB2_NEGOTIATE_SIGNING_REQUIRED,
        .signing_required = SMB2_NEGOTIATE_SIGNING_REQUIRED,
        .create_lease_size = sizeof(struct create_lease_v2),
};

struct smb_version_values smbdefault_values = {
        .version_string = SMBDEFAULT_VERSION_STRING,
        .protocol_id = SMB302_PROT_ID, /* doesn't matter, send protocol array */
        .req_capabilities = SMB2_GLOBAL_CAP_DFS | SMB2_GLOBAL_CAP_LEASING | SMB2_GLOBAL_CAP_LARGE_MTU | SMB2_GLOBAL_CAP_PERSISTENT_HANDLES | SMB2_GLOBAL_CAP_ENCRYPTION | SMB2_GLOBAL_CAP_DIRECTORY_LEASING,
        .large_lock_type = 0,
        .exclusive_lock_type = SMB2_LOCKFLAG_EXCLUSIVE,
        .shared_lock_type = SMB2_LOCKFLAG_SHARED,
        .unlock_lock_type = SMB2_LOCKFLAG_UNLOCK,
        .header_size = sizeof(struct smb2_hdr),
        .header_preamble_size = 0,
        .max_header_size = MAX_SMB2_HDR_SIZE,
        .read_rsp_size = sizeof(struct smb2_read_rsp) - 1,
        .lock_cmd = SMB2_LOCK,
        .cap_unix = 0,
        .cap_nt_find = SMB2_NT_FIND,
        .cap_large_files = SMB2_LARGE_FILES,
        .signing_enabled = SMB2_NEGOTIATE_SIGNING_ENABLED | SMB2_NEGOTIATE_SIGNING_REQUIRED,
        .signing_required = SMB2_NEGOTIATE_SIGNING_REQUIRED,
        .create_lease_size = sizeof(struct create_lease_v2),
};

struct smb_version_values smb30_values = {
        .version_string = SMB30_VERSION_STRING,
        .protocol_id = SMB30_PROT_ID,
        .req_capabilities = SMB2_GLOBAL_CAP_DFS | SMB2_GLOBAL_CAP_LEASING | SMB2_GLOBAL_CAP_LARGE_MTU | SMB2_GLOBAL_CAP_PERSISTENT_HANDLES | SMB2_GLOBAL_CAP_ENCRYPTION | SMB2_GLOBAL_CAP_DIRECTORY_LEASING,
        .large_lock_type = 0,
        .exclusive_lock_type = SMB2_LOCKFLAG_EXCLUSIVE,
        .shared_lock_type = SMB2_LOCKFLAG_SHARED,
        .unlock_lock_type = SMB2_LOCKFLAG_UNLOCK,
        .header_size = sizeof(struct smb2_hdr),
        .header_preamble_size = 0,
        .max_header_size = MAX_SMB2_HDR_SIZE,
        .read_rsp_size = sizeof(struct smb2_read_rsp) - 1,
        .lock_cmd = SMB2_LOCK,
        .cap_unix = 0,
        .cap_nt_find = SMB2_NT_FIND,
        .cap_large_files = SMB2_LARGE_FILES,
        .signing_enabled = SMB2_NEGOTIATE_SIGNING_ENABLED | SMB2_NEGOTIATE_SIGNING_REQUIRED,
        .signing_required = SMB2_NEGOTIATE_SIGNING_REQUIRED,
        .create_lease_size = sizeof(struct create_lease_v2),
};

struct smb_version_values smb302_values = {
        .version_string = SMB302_VERSION_STRING,
        .protocol_id = SMB302_PROT_ID,
        .req_capabilities = SMB2_GLOBAL_CAP_DFS | SMB2_GLOBAL_CAP_LEASING | SMB2_GLOBAL_CAP_LARGE_MTU | SMB2_GLOBAL_CAP_PERSISTENT_HANDLES | SMB2_GLOBAL_CAP_ENCRYPTION | SMB2_GLOBAL_CAP_DIRECTORY_LEASING,
        .large_lock_type = 0,
        .exclusive_lock_type = SMB2_LOCKFLAG_EXCLUSIVE,
        .shared_lock_type = SMB2_LOCKFLAG_SHARED,
        .unlock_lock_type = SMB2_LOCKFLAG_UNLOCK,
        .header_size = sizeof(struct smb2_hdr),
        .header_preamble_size = 0,
        .max_header_size = MAX_SMB2_HDR_SIZE,
        .read_rsp_size = sizeof(struct smb2_read_rsp) - 1,
        .lock_cmd = SMB2_LOCK,
        .cap_unix = 0,
        .cap_nt_find = SMB2_NT_FIND,
        .cap_large_files = SMB2_LARGE_FILES,
        .signing_enabled = SMB2_NEGOTIATE_SIGNING_ENABLED | SMB2_NEGOTIATE_SIGNING_REQUIRED,
        .signing_required = SMB2_NEGOTIATE_SIGNING_REQUIRED,
        .create_lease_size = sizeof(struct create_lease_v2),
};

struct smb_version_values smb311_values = {
        .version_string = SMB311_VERSION_STRING,
        .protocol_id = SMB311_PROT_ID,
        .req_capabilities = SMB2_GLOBAL_CAP_DFS | SMB2_GLOBAL_CAP_LEASING | SMB2_GLOBAL_CAP_LARGE_MTU | SMB2_GLOBAL_CAP_PERSISTENT_HANDLES | SMB2_GLOBAL_CAP_ENCRYPTION | SMB2_GLOBAL_CAP_DIRECTORY_LEASING,
        .large_lock_type = 0,
        .exclusive_lock_type = SMB2_LOCKFLAG_EXCLUSIVE,
        .shared_lock_type = SMB2_LOCKFLAG_SHARED,
        .unlock_lock_type = SMB2_LOCKFLAG_UNLOCK,
        .header_size = sizeof(struct smb2_hdr),
        .header_preamble_size = 0,
        .max_header_size = MAX_SMB2_HDR_SIZE,
        .read_rsp_size = sizeof(struct smb2_read_rsp) - 1,
        .lock_cmd = SMB2_LOCK,
        .cap_unix = 0,
        .cap_nt_find = SMB2_NT_FIND,
        .cap_large_files = SMB2_LARGE_FILES,
        .signing_enabled = SMB2_NEGOTIATE_SIGNING_ENABLED | SMB2_NEGOTIATE_SIGNING_REQUIRED,
        .signing_required = SMB2_NEGOTIATE_SIGNING_REQUIRED,
        .create_lease_size = sizeof(struct create_lease_v2),
};