[people/arne_f/kernel.git] / net / 9p / protocol.c

/*
 * net/9p/protocol.c
 *
 * 9P Protocol Support Code
 *
 *  Copyright (C) 2008 by Eric Van Hensbergen <ericvh@gmail.com>
 *
 *  Base on code from Anthony Liguori <aliguori@us.ibm.com>
 *  Copyright (C) 2008 by IBM, Corp.
 *
 *  This program is free software; you can redistribute it and/or modify
 *  it under the terms of the GNU General Public License version 2
 *  as published by the Free Software Foundation.
 *
 *  This program is distributed in the hope that it will be useful,
 *  but WITHOUT ANY WARRANTY; without even the implied warranty of
 *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 *  GNU General Public License for more details.
 *
 *  You should have received a copy of the GNU General Public License
 *  along with this program; if not, write to:
 *  Free Software Foundation
 *  51 Franklin Street, Fifth Floor
 *  Boston, MA  02111-1301  USA
 *
 */

#include <linux/module.h>
#include <linux/errno.h>
#include <linux/kernel.h>
#include <linux/uaccess.h>
#include <linux/slab.h>
#include <linux/sched.h>
#include <linux/stddef.h>
#include <linux/types.h>
#include <linux/uio.h>
#include <net/9p/9p.h>
#include <net/9p/client.h>
#include "protocol.h"

#include <trace/events/9p.h>

static int
p9pdu_writef(struct p9_fcall *pdu, int proto_version, const char *fmt, ...);

void p9stat_free(struct p9_wstat *stbuf)
{
	kfree(stbuf->name);
	stbuf->name = NULL;
	kfree(stbuf->uid);
	stbuf->uid = NULL;
	kfree(stbuf->gid);
	stbuf->gid = NULL;
	kfree(stbuf->muid);
	stbuf->muid = NULL;
	kfree(stbuf->extension);
	stbuf->extension = NULL;
}
EXPORT_SYMBOL(p9stat_free);

size_t pdu_read(struct p9_fcall *pdu, void *data, size_t size)
{
	size_t len = min(pdu->size - pdu->offset, size);
	memcpy(data, &pdu->sdata[pdu->offset], len);
	pdu->offset += len;
	return size - len;
}

static size_t pdu_write(struct p9_fcall *pdu, const void *data, size_t size)
{
	size_t len = min(pdu->capacity - pdu->size, size);
	memcpy(&pdu->sdata[pdu->size], data, len);
	pdu->size += len;
	return size - len;
}

static size_t
pdu_write_u(struct p9_fcall *pdu, struct iov_iter *from, size_t size)
{
	size_t len = min(pdu->capacity - pdu->size, size);
	struct iov_iter i = *from;
	if (copy_from_iter(&pdu->sdata[pdu->size], len, &i) != len)
		len = 0;

	pdu->size += len;
	return size - len;
}

/*
	b - int8_t
	w - int16_t
	d - int32_t
	q - int64_t
	s - string
	u - numeric uid
	g - numeric gid
	S - stat
	Q - qid
	D - data blob (int32_t size followed by void *, results are not freed)
	T - array of strings (int16_t count, followed by strings)
	R - array of qids (int16_t count, followed by qids)
	A - stat for 9p2000.L (p9_stat_dotl)
	? - if optional = 1, continue parsing
*/

static int
p9pdu_vreadf(struct p9_fcall *pdu, int proto_version, const char *fmt,
	va_list ap)
{
	const char *ptr;
	int errcode = 0;

	for (ptr = fmt; *ptr; ptr++) {
		switch (*ptr) {
		case 'b':{
				int8_t *val = va_arg(ap, int8_t *);
				if (pdu_read(pdu, val, sizeof(*val))) {
					errcode = -EFAULT;
					break;
				}
			}
			break;
		case 'w':{
				int16_t *val = va_arg(ap, int16_t *);
				__le16 le_val;
				if (pdu_read(pdu, &le_val, sizeof(le_val))) {
					errcode = -EFAULT;
					break;
				}
				*val = le16_to_cpu(le_val);
			}
			break;
		case 'd':{
				int32_t *val = va_arg(ap, int32_t *);
				__le32 le_val;
				if (pdu_read(pdu, &le_val, sizeof(le_val))) {
					errcode = -EFAULT;
					break;
				}
				*val = le32_to_cpu(le_val);
			}
			break;
		case 'q':{
				int64_t *val = va_arg(ap, int64_t *);
				__le64 le_val;
				if (pdu_read(pdu, &le_val, sizeof(le_val))) {
					errcode = -EFAULT;
					break;
				}
				*val = le64_to_cpu(le_val);
			}
			break;
		case 's':{
				char **sptr = va_arg(ap, char **);
				uint16_t len;

				errcode = p9pdu_readf(pdu, proto_version,
								"w", &len);
				if (errcode)
					break;

				*sptr = kmalloc(len + 1, GFP_NOFS);
				if (*sptr == NULL) {
					errcode = -EFAULT;
					break;
				}
				if (pdu_read(pdu, *sptr, len)) {
					errcode = -EFAULT;
					kfree(*sptr);
					*sptr = NULL;
				} else
					(*sptr)[len] = 0;
			}
			break;
		case 'u': {
				kuid_t *uid = va_arg(ap, kuid_t *);
				__le32 le_val;
				if (pdu_read(pdu, &le_val, sizeof(le_val))) {
					errcode = -EFAULT;
					break;
				}
				*uid = make_kuid(&init_user_ns,
						 le32_to_cpu(le_val));
			} break;
		case 'g': {
				kgid_t *gid = va_arg(ap, kgid_t *);
				__le32 le_val;
				if (pdu_read(pdu, &le_val, sizeof(le_val))) {
					errcode = -EFAULT;
					break;
				}
				*gid = make_kgid(&init_user_ns,
						 le32_to_cpu(le_val));
			} break;
		case 'Q':{
				struct p9_qid *qid =
				    va_arg(ap, struct p9_qid *);

				errcode = p9pdu_readf(pdu, proto_version, "bdq",
						      &qid->type, &qid->version,
						      &qid->path);
			}
			break;
		case 'S':{
				struct p9_wstat *stbuf =
				    va_arg(ap, struct p9_wstat *);

				memset(stbuf, 0, sizeof(struct p9_wstat));
				stbuf->n_uid = stbuf->n_muid = INVALID_UID;
				stbuf->n_gid = INVALID_GID;

				errcode =
				    p9pdu_readf(pdu, proto_version,
						"wwdQdddqssss?sugu",
						&stbuf->size, &stbuf->type,
						&stbuf->dev, &stbuf->qid,
						&stbuf->mode, &stbuf->atime,
						&stbuf->mtime, &stbuf->length,
						&stbuf->name, &stbuf->uid,
						&stbuf->gid, &stbuf->muid,
						&stbuf->extension,
						&stbuf->n_uid, &stbuf->n_gid,
						&stbuf->n_muid);
				if (errcode)
					p9stat_free(stbuf);
			}
			break;
		case 'D':{
				uint32_t *count = va_arg(ap, uint32_t *);
				void **data = va_arg(ap, void **);

				errcode =
				    p9pdu_readf(pdu, proto_version, "d", count);
				if (!errcode) {
					*count =
					    min_t(uint32_t, *count,
						  pdu->size - pdu->offset);
					*data = &pdu->sdata[pdu->offset];
				}
			}
			break;
		case 'T':{
				uint16_t *nwname = va_arg(ap, uint16_t *);
				char ***wnames = va_arg(ap, char ***);

				errcode = p9pdu_readf(pdu, proto_version,
								"w", nwname);
				if (!errcode) {
					*wnames =
					    kmalloc(sizeof(char *) * *nwname,
						    GFP_NOFS);
					if (!*wnames)
						errcode = -ENOMEM;
				}

				if (!errcode) {
					int i;

					for (i = 0; i < *nwname; i++) {
						errcode =
						    p9pdu_readf(pdu,
								proto_version,
								"s",
								&(*wnames)[i]);
						if (errcode)
							break;
					}
				}

				if (errcode) {
					if (*wnames) {
						int i;

						for (i = 0; i < *nwname; i++)
							kfree((*wnames)[i]);
					}
					kfree(*wnames);
					*wnames = NULL;
				}
			}
			break;
		case 'R':{
				uint16_t *nwqid = va_arg(ap, uint16_t *);
				struct p9_qid **wqids =
				    va_arg(ap, struct p9_qid **);

				*wqids = NULL;

				errcode =
				    p9pdu_readf(pdu, proto_version, "w", nwqid);
				if (!errcode) {
					*wqids =
					    kmalloc(*nwqid *
						    sizeof(struct p9_qid),
						    GFP_NOFS);
					if (*wqids == NULL)
						errcode = -ENOMEM;
				}

				if (!errcode) {
					int i;

					for (i = 0; i < *nwqid; i++) {
						errcode =
						    p9pdu_readf(pdu,
								proto_version,
								"Q",
								&(*wqids)[i]);
						if (errcode)
							break;
					}
				}

				if (errcode) {
					kfree(*wqids);
					*wqids = NULL;
				}
			}
			break;
		case 'A': {
				struct p9_stat_dotl *stbuf =
				    va_arg(ap, struct p9_stat_dotl *);

				memset(stbuf, 0, sizeof(struct p9_stat_dotl));
				errcode =
				    p9pdu_readf(pdu, proto_version,
					"qQdugqqqqqqqqqqqqqqq",
					&stbuf->st_result_mask,
					&stbuf->qid,
					&stbuf->st_mode,
					&stbuf->st_uid, &stbuf->st_gid,
					&stbuf->st_nlink,
					&stbuf->st_rdev, &stbuf->st_size,
					&stbuf->st_blksize, &stbuf->st_blocks,
					&stbuf->st_atime_sec,
					&stbuf->st_atime_nsec,
					&stbuf->st_mtime_sec,
					&stbuf->st_mtime_nsec,
					&stbuf->st_ctime_sec,
					&stbuf->st_ctime_nsec,
					&stbuf->st_btime_sec,
					&stbuf->st_btime_nsec,
					&stbuf->st_gen,
					&stbuf->st_data_version);
			}
			break;
		case '?':
			if ((proto_version != p9_proto_2000u) &&
				(proto_version != p9_proto_2000L))
				return 0;
			break;
		default:
			BUG();
			break;
		}

		if (errcode)
			break;
	}

	return errcode;
}

int
p9pdu_vwritef(struct p9_fcall *pdu, int proto_version, const char *fmt,
	va_list ap)
{
	const char *ptr;
	int errcode = 0;

	for (ptr = fmt; *ptr; ptr++) {
		switch (*ptr) {
		case 'b':{
				int8_t val = va_arg(ap, int);
				if (pdu_write(pdu, &val, sizeof(val)))
					errcode = -EFAULT;
			}
			break;
		case 'w':{
				__le16 val = cpu_to_le16(va_arg(ap, int));
				if (pdu_write(pdu, &val, sizeof(val)))
					errcode = -EFAULT;
			}
			break;
		case 'd':{
				__le32 val = cpu_to_le32(va_arg(ap, int32_t));
				if (pdu_write(pdu, &val, sizeof(val)))
					errcode = -EFAULT;
			}
			break;
		case 'q':{
				__le64 val = cpu_to_le64(va_arg(ap, int64_t));
				if (pdu_write(pdu, &val, sizeof(val)))
					errcode = -EFAULT;
			}
			break;
		case 's':{
				const char *sptr = va_arg(ap, const char *);
				uint16_t len = 0;
				if (sptr)
					len = min_t(size_t, strlen(sptr),
								USHRT_MAX);

				errcode = p9pdu_writef(pdu, proto_version,
								"w", len);
				if (!errcode && pdu_write(pdu, sptr, len))
					errcode = -EFAULT;
			}
			break;
		case 'u': {
				kuid_t uid = va_arg(ap, kuid_t);
				__le32 val = cpu_to_le32(
						from_kuid(&init_user_ns, uid));
				if (pdu_write(pdu, &val, sizeof(val)))
					errcode = -EFAULT;
			} break;
		case 'g': {
				kgid_t gid = va_arg(ap, kgid_t);
				__le32 val = cpu_to_le32(
						from_kgid(&init_user_ns, gid));
				if (pdu_write(pdu, &val, sizeof(val)))
					errcode = -EFAULT;
			} break;
		case 'Q':{
				const struct p9_qid *qid =
				    va_arg(ap, const struct p9_qid *);
				errcode =
				    p9pdu_writef(pdu, proto_version, "bdq",
						 qid->type, qid->version,
						 qid->path);
			} break;
		case 'S':{
				const struct p9_wstat *stbuf =
				    va_arg(ap, const struct p9_wstat *);
				errcode =
				    p9pdu_writef(pdu, proto_version,
						 "wwdQdddqssss?sugu",
						 stbuf->size, stbuf->type,
						 stbuf->dev, &stbuf->qid,
						 stbuf->mode, stbuf->atime,
						 stbuf->mtime, stbuf->length,
						 stbuf->name, stbuf->uid,
						 stbuf->gid, stbuf->muid,
						 stbuf->extension, stbuf->n_uid,
						 stbuf->n_gid, stbuf->n_muid);
			} break;
		case 'V':{
				uint32_t count = va_arg(ap, uint32_t);
				struct iov_iter *from =
						va_arg(ap, struct iov_iter *);
				errcode = p9pdu_writef(pdu, proto_version, "d",
									count);
				if (!errcode && pdu_write_u(pdu, from, count))
					errcode = -EFAULT;
			}
			break;
		case 'T':{
				uint16_t nwname = va_arg(ap, int);
				const char **wnames = va_arg(ap, const char **);

				errcode = p9pdu_writef(pdu, proto_version, "w",
									nwname);
				if (!errcode) {
					int i;

					for (i = 0; i < nwname; i++) {
						errcode =
						    p9pdu_writef(pdu,
								proto_version,
								 "s",
								 wnames[i]);
						if (errcode)
							break;
					}
				}
			}
			break;
		case 'R':{
				uint16_t nwqid = va_arg(ap, int);
				struct p9_qid *wqids =
				    va_arg(ap, struct p9_qid *);

				errcode = p9pdu_writef(pdu, proto_version, "w",
									nwqid);
				if (!errcode) {
					int i;

					for (i = 0; i < nwqid; i++) {
						errcode =
						    p9pdu_writef(pdu,
								proto_version,
								 "Q",
								 &wqids[i]);
						if (errcode)
							break;
					}
				}
			}
			break;
		case 'I':{
				struct p9_iattr_dotl *p9attr = va_arg(ap,
							struct p9_iattr_dotl *);

				errcode = p9pdu_writef(pdu, proto_version,
							"ddugqqqqq",
							p9attr->valid,
							p9attr->mode,
							p9attr->uid,
							p9attr->gid,
							p9attr->size,
							p9attr->atime_sec,
							p9attr->atime_nsec,
							p9attr->mtime_sec,
							p9attr->mtime_nsec);
			}
			break;
		case '?':
			if ((proto_version != p9_proto_2000u) &&
				(proto_version != p9_proto_2000L))
				return 0;
			break;
		default:
			BUG();
			break;
		}

		if (errcode)
			break;
	}

	return errcode;
}

int p9pdu_readf(struct p9_fcall *pdu, int proto_version, const char *fmt, ...)
{
	va_list ap;
	int ret;

	va_start(ap, fmt);
	ret = p9pdu_vreadf(pdu, proto_version, fmt, ap);
	va_end(ap);

	return ret;
}

static int
p9pdu_writef(struct p9_fcall *pdu, int proto_version, const char *fmt, ...)
{
	va_list ap;
	int ret;

	va_start(ap, fmt);
	ret = p9pdu_vwritef(pdu, proto_version, fmt, ap);
	va_end(ap);

	return ret;
}

int p9stat_read(struct p9_client *clnt, char *buf, int len, struct p9_wstat *st)
{
	struct p9_fcall fake_pdu;
	int ret;

	fake_pdu.size = len;
	fake_pdu.capacity = len;
	fake_pdu.sdata = buf;
	fake_pdu.offset = 0;

	ret = p9pdu_readf(&fake_pdu, clnt->proto_version, "S", st);
	if (ret) {
		p9_debug(P9_DEBUG_9P, "<<< p9stat_read failed: %d\n", ret);
		trace_9p_protocol_dump(clnt, &fake_pdu);
		return ret;
	}

	return fake_pdu.offset;
}
EXPORT_SYMBOL(p9stat_read);

int p9pdu_prepare(struct p9_fcall *pdu, int16_t tag, int8_t type)
{
	pdu->id = type;
	return p9pdu_writef(pdu, 0, "dbw", 0, type, tag);
}

int p9pdu_finalize(struct p9_client *clnt, struct p9_fcall *pdu)
{
	int size = pdu->size;
	int err;

	pdu->size = 0;
	err = p9pdu_writef(pdu, 0, "d", size);
	pdu->size = size;

	trace_9p_protocol_dump(clnt, pdu);
	p9_debug(P9_DEBUG_9P, ">>> size=%d type: %d tag: %d\n",
		 pdu->size, pdu->id, pdu->tag);

	return err;
}

void p9pdu_reset(struct p9_fcall *pdu)
{
	pdu->offset = 0;
	pdu->size = 0;
}

int p9dirent_read(struct p9_client *clnt, char *buf, int len,
		  struct p9_dirent *dirent)
{
	struct p9_fcall fake_pdu;
	int ret;
	char *nameptr;

	fake_pdu.size = len;
	fake_pdu.capacity = len;
	fake_pdu.sdata = buf;
	fake_pdu.offset = 0;

	ret = p9pdu_readf(&fake_pdu, clnt->proto_version, "Qqbs", &dirent->qid,
			  &dirent->d_off, &dirent->d_type, &nameptr);
	if (ret) {
		p9_debug(P9_DEBUG_9P, "<<< p9dirent_read failed: %d\n", ret);
		trace_9p_protocol_dump(clnt, &fake_pdu);
		goto out;
	}

	strcpy(dirent->d_name, nameptr);
	kfree(nameptr);

out:
	return fake_pdu.offset;
}
EXPORT_SYMBOL(p9dirent_read);
Commit	Line	Data
ace51c4d EVH	1	/*
	2	* net/9p/protocol.c
	3	*
	4	* 9P Protocol Support Code
	5	*
	6	* Copyright (C) 2008 by Eric Van Hensbergen <ericvh@gmail.com>
	7	*
	8	* Base on code from Anthony Liguori <aliguori@us.ibm.com>
	9	* Copyright (C) 2008 by IBM, Corp.
	10	*
	11	* This program is free software; you can redistribute it and/or modify
	12	* it under the terms of the GNU General Public License version 2
	13	* as published by the Free Software Foundation.
	14	*
	15	* This program is distributed in the hope that it will be useful,
	16	* but WITHOUT ANY WARRANTY; without even the implied warranty of
	17	* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
	18	* GNU General Public License for more details.
	19	*
	20	* You should have received a copy of the GNU General Public License
	21	* along with this program; if not, write to:
	22	* Free Software Foundation
	23	* 51 Franklin Street, Fifth Floor
	24	* Boston, MA 02111-1301 USA
	25	*
	26	*/
	27
	28	#include <linux/module.h>
	29	#include <linux/errno.h>
01b0c5cf	30	#include <linux/kernel.h>
51a87c55	31	#include <linux/uaccess.h>
5a0e3ad6	32	#include <linux/slab.h>
e7f4b8f1	33	#include <linux/sched.h>
01b0c5cf	34	#include <linux/stddef.h>
beeebc92	35	#include <linux/types.h>
4f3b35c1	36	#include <linux/uio.h>
ace51c4d EVH	37	#include <net/9p/9p.h>
	38	#include <net/9p/client.h>
	39	#include "protocol.h"
	40
348b5901 AK	41	#include <trace/events/9p.h>
348b5901 AK	42
ace51c4d	43	static int
342fee1d	44	p9pdu_writef(struct p9_fcall pdu, int proto_version, const char fmt, ...);
ace51c4d EVH	45
	46	void p9stat_free(struct p9_wstat *stbuf)
	47	{
	48	kfree(stbuf->name);
0cf4fa79	49	stbuf->name = NULL;
ace51c4d	50	kfree(stbuf->uid);
0cf4fa79	51	stbuf->uid = NULL;
ace51c4d	52	kfree(stbuf->gid);
0cf4fa79	53	stbuf->gid = NULL;
ace51c4d	54	kfree(stbuf->muid);
0cf4fa79	55	stbuf->muid = NULL;
ace51c4d	56	kfree(stbuf->extension);
0cf4fa79	57	stbuf->extension = NULL;
ace51c4d EVH	58	}
	59	EXPORT_SYMBOL(p9stat_free);
	60
abfa034e	61	size_t pdu_read(struct p9_fcall pdu, void data, size_t size)
ace51c4d	62	{
01b0c5cf	63	size_t len = min(pdu->size - pdu->offset, size);
ace51c4d EVH	64	memcpy(data, &pdu->sdata[pdu->offset], len);
	65	pdu->offset += len;
	66	return size - len;
	67	}
	68
	69	static size_t pdu_write(struct p9_fcall pdu, const void data, size_t size)
	70	{
01b0c5cf	71	size_t len = min(pdu->capacity - pdu->size, size);
ace51c4d EVH	72	memcpy(&pdu->sdata[pdu->size], data, len);
	73	pdu->size += len;
	74	return size - len;
	75	}
	76
51a87c55	77	static size_t
4f3b35c1	78	pdu_write_u(struct p9_fcall pdu, struct iov_iter from, size_t size)
51a87c55	79	{
01b0c5cf	80	size_t len = min(pdu->capacity - pdu->size, size);
4f3b35c1 AV	81	struct iov_iter i = *from;
4f3b35c1 AV	82	if (copy_from_iter(&pdu->sdata[pdu->size], len, &i) != len)
7b3bb3fe	83	len = 0;
51a87c55 EVH	84
	85	pdu->size += len;
	86	return size - len;
	87	}
	88
ace51c4d EVH	89	/*
	90	b - int8_t
	91	w - int16_t
	92	d - int32_t
	93	q - int64_t
	94	s - string
97fc8b1e EB	95	u - numeric uid
97fc8b1e EB	96	g - numeric gid
ace51c4d EVH	97	S - stat
	98	Q - qid
	99	D - data blob (int32_t size followed by void *, results are not freed)
	100	T - array of strings (int16_t count, followed by strings)
	101	R - array of qids (int16_t count, followed by qids)
f0853122	102	A - stat for 9p2000.L (p9_stat_dotl)
ace51c4d EVH	103	? - if optional = 1, continue parsing
	104	*/
	105
	106	static int
342fee1d SK	107	p9pdu_vreadf(struct p9_fcall pdu, int proto_version, const char fmt,
342fee1d SK	108	va_list ap)
ace51c4d EVH	109	{
	110	const char *ptr;
	111	int errcode = 0;
	112
	113	for (ptr = fmt; *ptr; ptr++) {
	114	switch (*ptr) {
	115	case 'b':{
	116	int8_t val = va_arg(ap, int8_t );
	117	if (pdu_read(pdu, val, sizeof(*val))) {
	118	errcode = -EFAULT;
	119	break;
	120	}
	121	}
	122	break;
	123	case 'w':{
	124	int16_t val = va_arg(ap, int16_t );
beeebc92 EVH	125	__le16 le_val;
beeebc92 EVH	126	if (pdu_read(pdu, &le_val, sizeof(le_val))) {
ace51c4d EVH	127	errcode = -EFAULT;
	128	break;
	129	}
beeebc92	130	*val = le16_to_cpu(le_val);
ace51c4d EVH	131	}
	132	break;
	133	case 'd':{
	134	int32_t val = va_arg(ap, int32_t );
beeebc92 EVH	135	__le32 le_val;
beeebc92 EVH	136	if (pdu_read(pdu, &le_val, sizeof(le_val))) {
ace51c4d EVH	137	errcode = -EFAULT;
	138	break;
	139	}
beeebc92	140	*val = le32_to_cpu(le_val);
ace51c4d EVH	141	}
	142	break;
	143	case 'q':{
	144	int64_t val = va_arg(ap, int64_t );
beeebc92 EVH	145	__le64 le_val;
beeebc92 EVH	146	if (pdu_read(pdu, &le_val, sizeof(le_val))) {
ace51c4d EVH	147	errcode = -EFAULT;
	148	break;
	149	}
beeebc92	150	*val = le64_to_cpu(le_val);
ace51c4d EVH	151	}
	152	break;
	153	case 's':{
e45c5405	154	char sptr = va_arg(ap, char );
219fd58b	155	uint16_t len;
ace51c4d	156
342fee1d SK	157	errcode = p9pdu_readf(pdu, proto_version,
342fee1d SK	158	"w", &len);
ace51c4d EVH	159	if (errcode)
	160	break;
	161
eeff66ef	162	*sptr = kmalloc(len + 1, GFP_NOFS);
e45c5405	163	if (*sptr == NULL) {
ace51c4d EVH	164	errcode = -EFAULT;
	165	break;
	166	}
219fd58b	167	if (pdu_read(pdu, *sptr, len)) {
ace51c4d	168	errcode = -EFAULT;
e45c5405 EVH	169	kfree(*sptr);
e45c5405 EVH	170	*sptr = NULL;
ace51c4d	171	} else
219fd58b	172	(*sptr)[len] = 0;
ace51c4d EVH	173	}
ace51c4d EVH	174	break;
97fc8b1e EB	175	case 'u': {
	176	kuid_t uid = va_arg(ap, kuid_t );
	177	__le32 le_val;
	178	if (pdu_read(pdu, &le_val, sizeof(le_val))) {
	179	errcode = -EFAULT;
	180	break;
	181	}
	182	*uid = make_kuid(&init_user_ns,
	183	le32_to_cpu(le_val));
	184	} break;
	185	case 'g': {
	186	kgid_t gid = va_arg(ap, kgid_t );
	187	__le32 le_val;
	188	if (pdu_read(pdu, &le_val, sizeof(le_val))) {
	189	errcode = -EFAULT;
	190	break;
	191	}
	192	*gid = make_kgid(&init_user_ns,
	193	le32_to_cpu(le_val));
	194	} break;
ace51c4d EVH	195	case 'Q':{
	196	struct p9_qid *qid =
	197	va_arg(ap, struct p9_qid *);
	198
342fee1d	199	errcode = p9pdu_readf(pdu, proto_version, "bdq",
ace51c4d EVH	200	&qid->type, &qid->version,
	201	&qid->path);
	202	}
	203	break;
	204	case 'S':{
	205	struct p9_wstat *stbuf =
	206	va_arg(ap, struct p9_wstat *);
	207
f0a0ac2e	208	memset(stbuf, 0, sizeof(struct p9_wstat));
447c5094 EB	209	stbuf->n_uid = stbuf->n_muid = INVALID_UID;
	210	stbuf->n_gid = INVALID_GID;
	211
ace51c4d	212	errcode =
342fee1d	213	p9pdu_readf(pdu, proto_version,
447c5094	214	"wwdQdddqssss?sugu",
ace51c4d EVH	215	&stbuf->size, &stbuf->type,
	216	&stbuf->dev, &stbuf->qid,
	217	&stbuf->mode, &stbuf->atime,
	218	&stbuf->mtime, &stbuf->length,
	219	&stbuf->name, &stbuf->uid,
	220	&stbuf->gid, &stbuf->muid,
	221	&stbuf->extension,
	222	&stbuf->n_uid, &stbuf->n_gid,
	223	&stbuf->n_muid);
	224	if (errcode)
	225	p9stat_free(stbuf);
	226	}
	227	break;
	228	case 'D':{
219fd58b	229	uint32_t count = va_arg(ap, uint32_t );
ace51c4d EVH	230	void data = va_arg(ap, void );
	231
	232	errcode =
342fee1d	233	p9pdu_readf(pdu, proto_version, "d", count);
ace51c4d EVH	234	if (!errcode) {
ace51c4d EVH	235	*count =
219fd58b	236	min_t(uint32_t, *count,
01b0c5cf	237	pdu->size - pdu->offset);
ace51c4d EVH	238	*data = &pdu->sdata[pdu->offset];
	239	}
	240	}
	241	break;
	242	case 'T':{
b76225e2	243	uint16_t nwname = va_arg(ap, uint16_t );
ace51c4d EVH	244	char *wnames = va_arg(ap, char *);
ace51c4d EVH	245
342fee1d SK	246	errcode = p9pdu_readf(pdu, proto_version,
342fee1d SK	247	"w", nwname);
ace51c4d EVH	248	if (!errcode) {
	249	*wnames =
	250	kmalloc(sizeof(char ) *nwname,
eeff66ef	251	GFP_NOFS);
ace51c4d EVH	252	if (!*wnames)
	253	errcode = -ENOMEM;
	254	}
	255
	256	if (!errcode) {
	257	int i;
	258
	259	for (i = 0; i < *nwname; i++) {
	260	errcode =
342fee1d SK	261	p9pdu_readf(pdu,
342fee1d SK	262	proto_version,
ace51c4d EVH	263	"s",
	264	&(*wnames)[i]);
	265	if (errcode)
	266	break;
	267	}
	268	}
	269
	270	if (errcode) {
	271	if (*wnames) {
	272	int i;
	273
	274	for (i = 0; i < *nwname; i++)
	275	kfree((*wnames)[i]);
	276	}
	277	kfree(*wnames);
	278	*wnames = NULL;
	279	}
	280	}
	281	break;
	282	case 'R':{
6250a8ba	283	uint16_t nwqid = va_arg(ap, uint16_t );
ace51c4d EVH	284	struct p9_qid **wqids =
	285	va_arg(ap, struct p9_qid **);
	286
	287	*wqids = NULL;
	288
	289	errcode =
342fee1d	290	p9pdu_readf(pdu, proto_version, "w", nwqid);
ace51c4d EVH	291	if (!errcode) {
	292	*wqids =
	293	kmalloc(nwqid
	294	sizeof(struct p9_qid),
eeff66ef	295	GFP_NOFS);
ace51c4d EVH	296	if (*wqids == NULL)
	297	errcode = -ENOMEM;
	298	}
	299
	300	if (!errcode) {
	301	int i;
	302
	303	for (i = 0; i < *nwqid; i++) {
	304	errcode =
342fee1d SK	305	p9pdu_readf(pdu,
342fee1d SK	306	proto_version,
ace51c4d EVH	307	"Q",
	308	&(*wqids)[i]);
	309	if (errcode)
	310	break;
	311	}
	312	}
	313
	314	if (errcode) {
	315	kfree(*wqids);
	316	*wqids = NULL;
	317	}
	318	}
	319	break;
f0853122 SK	320	case 'A': {
	321	struct p9_stat_dotl *stbuf =
	322	va_arg(ap, struct p9_stat_dotl *);
	323
	324	memset(stbuf, 0, sizeof(struct p9_stat_dotl));
	325	errcode =
	326	p9pdu_readf(pdu, proto_version,
447c5094	327	"qQdugqqqqqqqqqqqqqqq",
f0853122 SK	328	&stbuf->st_result_mask,
	329	&stbuf->qid,
	330	&stbuf->st_mode,
	331	&stbuf->st_uid, &stbuf->st_gid,
	332	&stbuf->st_nlink,
	333	&stbuf->st_rdev, &stbuf->st_size,
	334	&stbuf->st_blksize, &stbuf->st_blocks,
	335	&stbuf->st_atime_sec,
	336	&stbuf->st_atime_nsec,
	337	&stbuf->st_mtime_sec,
	338	&stbuf->st_mtime_nsec,
	339	&stbuf->st_ctime_sec,
	340	&stbuf->st_ctime_nsec,
	341	&stbuf->st_btime_sec,
	342	&stbuf->st_btime_nsec,
	343	&stbuf->st_gen,
	344	&stbuf->st_data_version);
	345	}
	346	break;
ace51c4d	347	case '?':
c56e4acf SK	348	if ((proto_version != p9_proto_2000u) &&
c56e4acf SK	349	(proto_version != p9_proto_2000L))
ace51c4d EVH	350	return 0;
	351	break;
	352	default:
	353	BUG();
	354	break;
	355	}
	356
	357	if (errcode)
	358	break;
	359	}
	360
	361	return errcode;
	362	}
	363
	364	int
342fee1d SK	365	p9pdu_vwritef(struct p9_fcall pdu, int proto_version, const char fmt,
342fee1d SK	366	va_list ap)
ace51c4d EVH	367	{
	368	const char *ptr;
	369	int errcode = 0;
	370
	371	for (ptr = fmt; *ptr; ptr++) {
	372	switch (*ptr) {
	373	case 'b':{
	374	int8_t val = va_arg(ap, int);
	375	if (pdu_write(pdu, &val, sizeof(val)))
	376	errcode = -EFAULT;
	377	}
	378	break;
	379	case 'w':{
beeebc92	380	__le16 val = cpu_to_le16(va_arg(ap, int));
ace51c4d EVH	381	if (pdu_write(pdu, &val, sizeof(val)))
	382	errcode = -EFAULT;
	383	}
	384	break;
	385	case 'd':{
beeebc92	386	__le32 val = cpu_to_le32(va_arg(ap, int32_t));
ace51c4d EVH	387	if (pdu_write(pdu, &val, sizeof(val)))
	388	errcode = -EFAULT;
	389	}
	390	break;
	391	case 'q':{
beeebc92	392	__le64 val = cpu_to_le64(va_arg(ap, int64_t));
ace51c4d EVH	393	if (pdu_write(pdu, &val, sizeof(val)))
	394	errcode = -EFAULT;
	395	}
	396	break;
	397	case 's':{
e45c5405	398	const char sptr = va_arg(ap, const char );
219fd58b	399	uint16_t len = 0;
e45c5405	400	if (sptr)
d31bb4f0	401	len = min_t(size_t, strlen(sptr),
219fd58b	402	USHRT_MAX);
ace51c4d	403
342fee1d SK	404	errcode = p9pdu_writef(pdu, proto_version,
342fee1d SK	405	"w", len);
e45c5405	406	if (!errcode && pdu_write(pdu, sptr, len))
ace51c4d EVH	407	errcode = -EFAULT;
	408	}
	409	break;
97fc8b1e EB	410	case 'u': {
	411	kuid_t uid = va_arg(ap, kuid_t);
	412	__le32 val = cpu_to_le32(
	413	from_kuid(&init_user_ns, uid));
	414	if (pdu_write(pdu, &val, sizeof(val)))
	415	errcode = -EFAULT;
	416	} break;
	417	case 'g': {
	418	kgid_t gid = va_arg(ap, kgid_t);
	419	__le32 val = cpu_to_le32(
	420	from_kgid(&init_user_ns, gid));
	421	if (pdu_write(pdu, &val, sizeof(val)))
	422	errcode = -EFAULT;
	423	} break;
ace51c4d EVH	424	case 'Q':{
	425	const struct p9_qid *qid =
	426	va_arg(ap, const struct p9_qid *);
	427	errcode =
342fee1d	428	p9pdu_writef(pdu, proto_version, "bdq",
ace51c4d EVH	429	qid->type, qid->version,
	430	qid->path);
	431	} break;
	432	case 'S':{
	433	const struct p9_wstat *stbuf =
	434	va_arg(ap, const struct p9_wstat *);
	435	errcode =
342fee1d	436	p9pdu_writef(pdu, proto_version,
447c5094	437	"wwdQdddqssss?sugu",
ace51c4d	438	stbuf->size, stbuf->type,
51a87c55	439	stbuf->dev, &stbuf->qid,
ace51c4d EVH	440	stbuf->mode, stbuf->atime,
	441	stbuf->mtime, stbuf->length,
	442	stbuf->name, stbuf->uid,
	443	stbuf->gid, stbuf->muid,
	444	stbuf->extension, stbuf->n_uid,
	445	stbuf->n_gid, stbuf->n_muid);
	446	} break;
4f3b35c1	447	case 'V':{
6250a8ba	448	uint32_t count = va_arg(ap, uint32_t);
4f3b35c1 AV	449	struct iov_iter *from =
4f3b35c1 AV	450	va_arg(ap, struct iov_iter *);
342fee1d SK	451	errcode = p9pdu_writef(pdu, proto_version, "d",
342fee1d SK	452	count);
4f3b35c1	453	if (!errcode && pdu_write_u(pdu, from, count))
51a87c55 EVH	454	errcode = -EFAULT;
	455	}
	456	break;
ace51c4d	457	case 'T':{
b76225e2	458	uint16_t nwname = va_arg(ap, int);
ace51c4d EVH	459	const char wnames = va_arg(ap, const char );
ace51c4d EVH	460
342fee1d SK	461	errcode = p9pdu_writef(pdu, proto_version, "w",
342fee1d SK	462	nwname);
ace51c4d EVH	463	if (!errcode) {
	464	int i;
	465
	466	for (i = 0; i < nwname; i++) {
	467	errcode =
342fee1d SK	468	p9pdu_writef(pdu,
342fee1d SK	469	proto_version,
ace51c4d EVH	470	"s",
	471	wnames[i]);
	472	if (errcode)
	473	break;
	474	}
	475	}
	476	}
	477	break;
	478	case 'R':{
6250a8ba	479	uint16_t nwqid = va_arg(ap, int);
ace51c4d EVH	480	struct p9_qid *wqids =
	481	va_arg(ap, struct p9_qid *);
	482
342fee1d SK	483	errcode = p9pdu_writef(pdu, proto_version, "w",
342fee1d SK	484	nwqid);
ace51c4d EVH	485	if (!errcode) {
	486	int i;
	487
	488	for (i = 0; i < nwqid; i++) {
	489	errcode =
342fee1d SK	490	p9pdu_writef(pdu,
342fee1d SK	491	proto_version,
ace51c4d EVH	492	"Q",
	493	&wqids[i]);
	494	if (errcode)
	495	break;
	496	}
	497	}
	498	}
	499	break;
87d7845a SK	500	case 'I':{
	501	struct p9_iattr_dotl *p9attr = va_arg(ap,
	502	struct p9_iattr_dotl *);
	503
	504	errcode = p9pdu_writef(pdu, proto_version,
447c5094	505	"ddugqqqqq",
87d7845a SK	506	p9attr->valid,
	507	p9attr->mode,
	508	p9attr->uid,
	509	p9attr->gid,
	510	p9attr->size,
	511	p9attr->atime_sec,
	512	p9attr->atime_nsec,
	513	p9attr->mtime_sec,
	514	p9attr->mtime_nsec);
	515	}
	516	break;
ace51c4d	517	case '?':
c56e4acf SK	518	if ((proto_version != p9_proto_2000u) &&
c56e4acf SK	519	(proto_version != p9_proto_2000L))
ace51c4d EVH	520	return 0;
	521	break;
	522	default:
	523	BUG();
	524	break;
	525	}
	526
	527	if (errcode)
	528	break;
	529	}
	530
	531	return errcode;
	532	}
	533
342fee1d	534	int p9pdu_readf(struct p9_fcall pdu, int proto_version, const char fmt, ...)
ace51c4d EVH	535	{
	536	va_list ap;
	537	int ret;
	538
	539	va_start(ap, fmt);
342fee1d	540	ret = p9pdu_vreadf(pdu, proto_version, fmt, ap);
ace51c4d EVH	541	va_end(ap);
	542
	543	return ret;
	544	}
	545
	546	static int
342fee1d	547	p9pdu_writef(struct p9_fcall pdu, int proto_version, const char fmt, ...)
ace51c4d EVH	548	{
	549	va_list ap;
	550	int ret;
	551
	552	va_start(ap, fmt);
342fee1d	553	ret = p9pdu_vwritef(pdu, proto_version, fmt, ap);
ace51c4d EVH	554	va_end(ap);
	555
	556	return ret;
	557	}
51a87c55	558
348b5901	559	int p9stat_read(struct p9_client clnt, char buf, int len, struct p9_wstat *st)
02da398b EVH	560	{
02da398b EVH	561	struct p9_fcall fake_pdu;
e7f4b8f1	562	int ret;
02da398b EVH	563
	564	fake_pdu.size = len;
	565	fake_pdu.capacity = len;
	566	fake_pdu.sdata = buf;
	567	fake_pdu.offset = 0;
	568
348b5901	569	ret = p9pdu_readf(&fake_pdu, clnt->proto_version, "S", st);
e7f4b8f1	570	if (ret) {
5d385153	571	p9_debug(P9_DEBUG_9P, "<<< p9stat_read failed: %d\n", ret);
348b5901	572	trace_9p_protocol_dump(clnt, &fake_pdu);
fea7d0d3	573	return ret;
e7f4b8f1 EVH	574	}
e7f4b8f1 EVH	575
fea7d0d3	576	return fake_pdu.offset;
02da398b EVH	577	}
	578	EXPORT_SYMBOL(p9stat_read);
	579
51a87c55 EVH	580	int p9pdu_prepare(struct p9_fcall *pdu, int16_t tag, int8_t type)
51a87c55 EVH	581	{
9bb6c10a	582	pdu->id = type;
51a87c55 EVH	583	return p9pdu_writef(pdu, 0, "dbw", 0, type, tag);
	584	}
	585
348b5901	586	int p9pdu_finalize(struct p9_client clnt, struct p9_fcall pdu)
51a87c55 EVH	587	{
	588	int size = pdu->size;
	589	int err;
	590
	591	pdu->size = 0;
	592	err = p9pdu_writef(pdu, 0, "d", size);
	593	pdu->size = size;
	594
348b5901	595	trace_9p_protocol_dump(clnt, pdu);
5d385153 JP	596	p9_debug(P9_DEBUG_9P, ">>> size=%d type: %d tag: %d\n",
5d385153 JP	597	pdu->size, pdu->id, pdu->tag);
e7f4b8f1	598
51a87c55 EVH	599	return err;
	600	}
	601
	602	void p9pdu_reset(struct p9_fcall *pdu)
	603	{
	604	pdu->offset = 0;
	605	pdu->size = 0;
	606	}
7751bdb3	607
348b5901 AK	608	int p9dirent_read(struct p9_client clnt, char buf, int len,
348b5901 AK	609	struct p9_dirent *dirent)
7751bdb3 SK	610	{
	611	struct p9_fcall fake_pdu;
	612	int ret;
	613	char *nameptr;
	614
	615	fake_pdu.size = len;
	616	fake_pdu.capacity = len;
	617	fake_pdu.sdata = buf;
	618	fake_pdu.offset = 0;
	619
348b5901 AK	620	ret = p9pdu_readf(&fake_pdu, clnt->proto_version, "Qqbs", &dirent->qid,
348b5901 AK	621	&dirent->d_off, &dirent->d_type, &nameptr);
7751bdb3	622	if (ret) {
5d385153	623	p9_debug(P9_DEBUG_9P, "<<< p9dirent_read failed: %d\n", ret);
348b5901	624	trace_9p_protocol_dump(clnt, &fake_pdu);
7751bdb3 SK	625	goto out;
	626	}
	627
	628	strcpy(dirent->d_name, nameptr);
1b0bcbcf	629	kfree(nameptr);
7751bdb3 SK	630
	631	out:
	632	return fake_pdu.offset;
	633	}
	634	EXPORT_SYMBOL(p9dirent_read);