[people/ms/linux.git] / fs / lockd / svcsubs.c

// SPDX-License-Identifier: GPL-2.0-only
/*
 * linux/fs/lockd/svcsubs.c
 *
 * Various support routines for the NLM server.
 *
 * Copyright (C) 1996, Olaf Kirch <okir@monad.swb.de>
 */

#include <linux/types.h>
#include <linux/string.h>
#include <linux/time.h>
#include <linux/in.h>
#include <linux/slab.h>
#include <linux/mutex.h>
#include <linux/sunrpc/svc.h>
#include <linux/sunrpc/addr.h>
#include <linux/lockd/lockd.h>
#include <linux/lockd/share.h>
#include <linux/module.h>
#include <linux/mount.h>
#include <uapi/linux/nfs2.h>

#define NLMDBG_FACILITY		NLMDBG_SVCSUBS


/*
 * Global file hash table
 */
#define FILE_HASH_BITS		7
#define FILE_NRHASH		(1<<FILE_HASH_BITS)
static struct hlist_head	nlm_files[FILE_NRHASH];
static DEFINE_MUTEX(nlm_file_mutex);

#ifdef CONFIG_SUNRPC_DEBUG
static inline void nlm_debug_print_fh(char *msg, struct nfs_fh *f)
{
	u32 *fhp = (u32*)f->data;

	/* print the first 32 bytes of the fh */
	dprintk("lockd: %s (%08x %08x %08x %08x %08x %08x %08x %08x)\n",
		msg, fhp[0], fhp[1], fhp[2], fhp[3],
		fhp[4], fhp[5], fhp[6], fhp[7]);
}

static inline void nlm_debug_print_file(char *msg, struct nlm_file *file)
{
	struct inode *inode = nlmsvc_file_inode(file);

	dprintk("lockd: %s %s/%ld\n",
		msg, inode->i_sb->s_id, inode->i_ino);
}
#else
static inline void nlm_debug_print_fh(char *msg, struct nfs_fh *f)
{
	return;
}

static inline void nlm_debug_print_file(char *msg, struct nlm_file *file)
{
	return;
}
#endif

static inline unsigned int file_hash(struct nfs_fh *f)
{
	unsigned int tmp=0;
	int i;
	for (i=0; i<NFS2_FHSIZE;i++)
		tmp += f->data[i];
	return tmp & (FILE_NRHASH - 1);
}

int lock_to_openmode(struct file_lock *lock)
{
	return (lock->fl_type == F_WRLCK) ? O_WRONLY : O_RDONLY;
}

/*
 * Open the file. Note that if we're reexporting, for example,
 * this could block the lockd thread for a while.
 *
 * We have to make sure we have the right credential to open
 * the file.
 */
static __be32 nlm_do_fopen(struct svc_rqst *rqstp,
			   struct nlm_file *file, int mode)
{
	struct file **fp = &file->f_file[mode];
	__be32	nfserr;

	if (*fp)
		return 0;
	nfserr = nlmsvc_ops->fopen(rqstp, &file->f_handle, fp, mode);
	if (nfserr)
		dprintk("lockd: open failed (error %d)\n", nfserr);
	return nfserr;
}

/*
 * Lookup file info. If it doesn't exist, create a file info struct
 * and open a (VFS) file for the given inode.
 */
__be32
nlm_lookup_file(struct svc_rqst *rqstp, struct nlm_file **result,
					struct nlm_lock *lock)
{
	struct nlm_file	*file;
	unsigned int	hash;
	__be32		nfserr;
	int		mode;

	nlm_debug_print_fh("nlm_lookup_file", &lock->fh);

	hash = file_hash(&lock->fh);
	mode = lock_to_openmode(&lock->fl);

	/* Lock file table */
	mutex_lock(&nlm_file_mutex);

	hlist_for_each_entry(file, &nlm_files[hash], f_list)
		if (!nfs_compare_fh(&file->f_handle, &lock->fh)) {
			mutex_lock(&file->f_mutex);
			nfserr = nlm_do_fopen(rqstp, file, mode);
			mutex_unlock(&file->f_mutex);
			goto found;
		}
	nlm_debug_print_fh("creating file for", &lock->fh);

	nfserr = nlm_lck_denied_nolocks;
	file = kzalloc(sizeof(*file), GFP_KERNEL);
	if (!file)
		goto out_free;

	memcpy(&file->f_handle, &lock->fh, sizeof(struct nfs_fh));
	mutex_init(&file->f_mutex);
	INIT_HLIST_NODE(&file->f_list);
	INIT_LIST_HEAD(&file->f_blocks);

	nfserr = nlm_do_fopen(rqstp, file, mode);
	if (nfserr)
		goto out_unlock;

	hlist_add_head(&file->f_list, &nlm_files[hash]);

found:
	dprintk("lockd: found file %p (count %d)\n", file, file->f_count);
	*result = file;
	file->f_count++;

out_unlock:
	mutex_unlock(&nlm_file_mutex);
	return nfserr;

out_free:
	kfree(file);
	goto out_unlock;
}

/*
 * Delete a file after having released all locks, blocks and shares
 */
static inline void
nlm_delete_file(struct nlm_file *file)
{
	nlm_debug_print_file("closing file", file);
	if (!hlist_unhashed(&file->f_list)) {
		hlist_del(&file->f_list);
		if (file->f_file[O_RDONLY])
			nlmsvc_ops->fclose(file->f_file[O_RDONLY]);
		if (file->f_file[O_WRONLY])
			nlmsvc_ops->fclose(file->f_file[O_WRONLY]);
		kfree(file);
	} else {
		printk(KERN_WARNING "lockd: attempt to release unknown file!\n");
	}
}

static int nlm_unlock_files(struct nlm_file *file, fl_owner_t owner)
{
	struct file_lock lock;

	locks_init_lock(&lock);
	lock.fl_type  = F_UNLCK;
	lock.fl_start = 0;
	lock.fl_end   = OFFSET_MAX;
	lock.fl_owner = owner;
	if (file->f_file[O_RDONLY] &&
	    vfs_lock_file(file->f_file[O_RDONLY], F_SETLK, &lock, NULL))
		goto out_err;
	if (file->f_file[O_WRONLY] &&
	    vfs_lock_file(file->f_file[O_WRONLY], F_SETLK, &lock, NULL))
		goto out_err;
	return 0;
out_err:
	pr_warn("lockd: unlock failure in %s:%d\n", __FILE__, __LINE__);
	return 1;
}

/*
 * Loop over all locks on the given file and perform the specified
 * action.
 */
static int
nlm_traverse_locks(struct nlm_host *host, struct nlm_file *file,
			nlm_host_match_fn_t match)
{
	struct inode	 *inode = nlmsvc_file_inode(file);
	struct file_lock *fl;
	struct file_lock_context *flctx = inode->i_flctx;
	struct nlm_host	 *lockhost;

	if (!flctx || list_empty_careful(&flctx->flc_posix))
		return 0;
again:
	file->f_locks = 0;
	spin_lock(&flctx->flc_lock);
	list_for_each_entry(fl, &flctx->flc_posix, fl_list) {
		if (fl->fl_lmops != &nlmsvc_lock_operations)
			continue;

		/* update current lock count */
		file->f_locks++;

		lockhost = ((struct nlm_lockowner *)fl->fl_owner)->host;
		if (match(lockhost, host)) {

			spin_unlock(&flctx->flc_lock);
			if (nlm_unlock_files(file, fl->fl_owner))
				return 1;
			goto again;
		}
	}
	spin_unlock(&flctx->flc_lock);

	return 0;
}

static int
nlmsvc_always_match(void *dummy1, struct nlm_host *dummy2)
{
	return 1;
}

/*
 * Inspect a single file
 */
static inline int
nlm_inspect_file(struct nlm_host *host, struct nlm_file *file, nlm_host_match_fn_t match)
{
	nlmsvc_traverse_blocks(host, file, match);
	nlmsvc_traverse_shares(host, file, match);
	return nlm_traverse_locks(host, file, match);
}

/*
 * Quick check whether there are still any locks, blocks or
 * shares on a given file.
 */
static inline int
nlm_file_inuse(struct nlm_file *file)
{
	struct inode	 *inode = nlmsvc_file_inode(file);
	struct file_lock *fl;
	struct file_lock_context *flctx = inode->i_flctx;

	if (file->f_count || !list_empty(&file->f_blocks) || file->f_shares)
		return 1;

	if (flctx && !list_empty_careful(&flctx->flc_posix)) {
		spin_lock(&flctx->flc_lock);
		list_for_each_entry(fl, &flctx->flc_posix, fl_list) {
			if (fl->fl_lmops == &nlmsvc_lock_operations) {
				spin_unlock(&flctx->flc_lock);
				return 1;
			}
		}
		spin_unlock(&flctx->flc_lock);
	}
	file->f_locks = 0;
	return 0;
}

static void nlm_close_files(struct nlm_file *file)
{
	if (file->f_file[O_RDONLY])
		nlmsvc_ops->fclose(file->f_file[O_RDONLY]);
	if (file->f_file[O_WRONLY])
		nlmsvc_ops->fclose(file->f_file[O_WRONLY]);
}

/*
 * Loop over all files in the file table.
 */
static int
nlm_traverse_files(void *data, nlm_host_match_fn_t match,
		int (*is_failover_file)(void *data, struct nlm_file *file))
{
	struct hlist_node *next;
	struct nlm_file	*file;
	int i, ret = 0;

	mutex_lock(&nlm_file_mutex);
	for (i = 0; i < FILE_NRHASH; i++) {
		hlist_for_each_entry_safe(file, next, &nlm_files[i], f_list) {
			if (is_failover_file && !is_failover_file(data, file))
				continue;
			file->f_count++;
			mutex_unlock(&nlm_file_mutex);

			/* Traverse locks, blocks and shares of this file
			 * and update file->f_locks count */
			if (nlm_inspect_file(data, file, match))
				ret = 1;

			mutex_lock(&nlm_file_mutex);
			file->f_count--;
			/* No more references to this file. Let go of it. */
			if (list_empty(&file->f_blocks) && !file->f_locks
			 && !file->f_shares && !file->f_count) {
				hlist_del(&file->f_list);
				nlm_close_files(file);
				kfree(file);
			}
		}
	}
	mutex_unlock(&nlm_file_mutex);
	return ret;
}

/*
 * Release file. If there are no more remote locks on this file,
 * close it and free the handle.
 *
 * Note that we can't do proper reference counting without major
 * contortions because the code in fs/locks.c creates, deletes and
 * splits locks without notification. Our only way is to walk the
 * entire lock list each time we remove a lock.
 */
void
nlm_release_file(struct nlm_file *file)
{
	dprintk("lockd: nlm_release_file(%p, ct = %d)\n",
				file, file->f_count);

	/* Lock file table */
	mutex_lock(&nlm_file_mutex);

	/* If there are no more locks etc, delete the file */
	if (--file->f_count == 0 && !nlm_file_inuse(file))
		nlm_delete_file(file);

	mutex_unlock(&nlm_file_mutex);
}

/*
 * Helpers function for resource traversal
 *
 * nlmsvc_mark_host:
 *	used by the garbage collector; simply sets h_inuse only for those
 *	hosts, which passed network check.
 *	Always returns 0.
 *
 * nlmsvc_same_host:
 *	returns 1 iff the two hosts match. Used to release
 *	all resources bound to a specific host.
 *
 * nlmsvc_is_client:
 *	returns 1 iff the host is a client.
 *	Used by nlmsvc_invalidate_all
 */

static int
nlmsvc_mark_host(void *data, struct nlm_host *hint)
{
	struct nlm_host *host = data;

	if ((hint->net == NULL) ||
	    (host->net == hint->net))
		host->h_inuse = 1;
	return 0;
}

static int
nlmsvc_same_host(void *data, struct nlm_host *other)
{
	struct nlm_host *host = data;

	return host == other;
}

static int
nlmsvc_is_client(void *data, struct nlm_host *dummy)
{
	struct nlm_host *host = data;

	if (host->h_server) {
		/* we are destroying locks even though the client
		 * hasn't asked us too, so don't unmonitor the
		 * client
		 */
		if (host->h_nsmhandle)
			host->h_nsmhandle->sm_sticky = 1;
		return 1;
	} else
		return 0;
}

/*
 * Mark all hosts that still hold resources
 */
void
nlmsvc_mark_resources(struct net *net)
{
	struct nlm_host hint;

	dprintk("lockd: %s for net %x\n", __func__, net ? net->ns.inum : 0);
	hint.net = net;
	nlm_traverse_files(&hint, nlmsvc_mark_host, NULL);
}

/*
 * Release all resources held by the given client
 */
void
nlmsvc_free_host_resources(struct nlm_host *host)
{
	dprintk("lockd: nlmsvc_free_host_resources\n");

	if (nlm_traverse_files(host, nlmsvc_same_host, NULL)) {
		printk(KERN_WARNING
			"lockd: couldn't remove all locks held by %s\n",
			host->h_name);
		BUG();
	}
}

/**
 * nlmsvc_invalidate_all - remove all locks held for clients
 *
 * Release all locks held by NFS clients.
 *
 */
void
nlmsvc_invalidate_all(void)
{
	/*
	 * Previously, the code would call
	 * nlmsvc_free_host_resources for each client in
	 * turn, which is about as inefficient as it gets.
	 * Now we just do it once in nlm_traverse_files.
	 */
	nlm_traverse_files(NULL, nlmsvc_is_client, NULL);
}


static int
nlmsvc_match_sb(void *datap, struct nlm_file *file)
{
	struct super_block *sb = datap;

	return sb == nlmsvc_file_inode(file)->i_sb;
}

/**
 * nlmsvc_unlock_all_by_sb - release locks held on this file system
 * @sb: super block
 *
 * Release all locks held by clients accessing this file system.
 */
int
nlmsvc_unlock_all_by_sb(struct super_block *sb)
{
	int ret;

	ret = nlm_traverse_files(sb, nlmsvc_always_match, nlmsvc_match_sb);
	return ret ? -EIO : 0;
}
EXPORT_SYMBOL_GPL(nlmsvc_unlock_all_by_sb);

static int
nlmsvc_match_ip(void *datap, struct nlm_host *host)
{
	return rpc_cmp_addr(nlm_srcaddr(host), datap);
}

/**
 * nlmsvc_unlock_all_by_ip - release local locks by IP address
 * @server_addr: server's IP address as seen by clients
 *
 * Release all locks held by clients accessing this host
 * via the passed in IP address.
 */
int
nlmsvc_unlock_all_by_ip(struct sockaddr *server_addr)
{
	int ret;

	ret = nlm_traverse_files(server_addr, nlmsvc_match_ip, NULL);
	return ret ? -EIO : 0;
}
EXPORT_SYMBOL_GPL(nlmsvc_unlock_all_by_ip);
Commit	Line	Data
457c8996	1	// SPDX-License-Identifier: GPL-2.0-only
1da177e4 LT	2	/*
	3	* linux/fs/lockd/svcsubs.c
	4	*
	5	* Various support routines for the NLM server.
	6	*
	7	* Copyright (C) 1996, Olaf Kirch <okir@monad.swb.de>
	8	*/
	9
1da177e4 LT	10	#include <linux/types.h>
	11	#include <linux/string.h>
	12	#include <linux/time.h>
	13	#include <linux/in.h>
5a0e3ad6	14	#include <linux/slab.h>
353ab6e9	15	#include <linux/mutex.h>
1da177e4	16	#include <linux/sunrpc/svc.h>
5976687a	17	#include <linux/sunrpc/addr.h>
1da177e4 LT	18	#include <linux/lockd/lockd.h>
1da177e4 LT	19	#include <linux/lockd/share.h>
4373ea84 WC	20	#include <linux/module.h>
4373ea84 WC	21	#include <linux/mount.h>
9c69de4c	22	#include <uapi/linux/nfs2.h>
1da177e4 LT	23
	24	#define NLMDBG_FACILITY NLMDBG_SVCSUBS
	25
	26
	27	/*
	28	* Global file hash table
	29	*/
07ba8063	30	#define FILE_HASH_BITS 7
1da177e4	31	#define FILE_NRHASH (1<<FILE_HASH_BITS)
07ba8063	32	static struct hlist_head nlm_files[FILE_NRHASH];
353ab6e9	33	static DEFINE_MUTEX(nlm_file_mutex);
1da177e4	34
135dd002	35	#ifdef CONFIG_SUNRPC_DEBUG
0bbacc40 CL	36	static inline void nlm_debug_print_fh(char msg, struct nfs_fh f)
	37	{
	38	u32 fhp = (u32)f->data;
	39
	40	/* print the first 32 bytes of the fh */
	41	dprintk("lockd: %s (%08x %08x %08x %08x %08x %08x %08x %08x)\n",
	42	msg, fhp[0], fhp[1], fhp[2], fhp[3],
	43	fhp[4], fhp[5], fhp[6], fhp[7]);
	44	}
	45
	46	static inline void nlm_debug_print_file(char msg, struct nlm_file file)
	47	{
a81041b7	48	struct inode *inode = nlmsvc_file_inode(file);
0bbacc40 CL	49
	50	dprintk("lockd: %s %s/%ld\n",
	51	msg, inode->i_sb->s_id, inode->i_ino);
	52	}
	53	#else
	54	static inline void nlm_debug_print_fh(char msg, struct nfs_fh f)
	55	{
	56	return;
	57	}
	58
	59	static inline void nlm_debug_print_file(char msg, struct nlm_file file)
	60	{
	61	return;
	62	}
	63	#endif
	64
1da177e4 LT	65	static inline unsigned int file_hash(struct nfs_fh *f)
	66	{
	67	unsigned int tmp=0;
	68	int i;
	69	for (i=0; i<NFS2_FHSIZE;i++)
	70	tmp += f->data[i];
	71	return tmp & (FILE_NRHASH - 1);
	72	}
	73
7f024fcd BF	74	int lock_to_openmode(struct file_lock *lock)
	75	{
	76	return (lock->fl_type == F_WRLCK) ? O_WRONLY : O_RDONLY;
	77	}
	78
	79	/*
	80	* Open the file. Note that if we're reexporting, for example,
	81	* this could block the lockd thread for a while.
	82	*
	83	* We have to make sure we have the right credential to open
	84	* the file.
	85	*/
	86	static __be32 nlm_do_fopen(struct svc_rqst *rqstp,
	87	struct nlm_file *file, int mode)
	88	{
	89	struct file **fp = &file->f_file[mode];
	90	__be32 nfserr;
	91
	92	if (*fp)
	93	return 0;
	94	nfserr = nlmsvc_ops->fopen(rqstp, &file->f_handle, fp, mode);
	95	if (nfserr)
	96	dprintk("lockd: open failed (error %d)\n", nfserr);
	97	return nfserr;
	98	}
	99
1da177e4 LT	100	/*
	101	* Lookup file info. If it doesn't exist, create a file info struct
	102	* and open a (VFS) file for the given inode.
1da177e4	103	*/
52921e02	104	__be32
1da177e4	105	nlm_lookup_file(struct svc_rqst rqstp, struct nlm_file *result,
2dc6f19e	106	struct nlm_lock *lock)
1da177e4 LT	107	{
	108	struct nlm_file *file;
	109	unsigned int hash;
52921e02	110	__be32 nfserr;
7f024fcd	111	int mode;
1da177e4	112
2dc6f19e	113	nlm_debug_print_fh("nlm_lookup_file", &lock->fh);
1da177e4	114
2dc6f19e	115	hash = file_hash(&lock->fh);
7f024fcd	116	mode = lock_to_openmode(&lock->fl);
1da177e4 LT	117
1da177e4 LT	118	/* Lock file table */
353ab6e9	119	mutex_lock(&nlm_file_mutex);
1da177e4	120
b67bfe0d	121	hlist_for_each_entry(file, &nlm_files[hash], f_list)
7f024fcd BF	122	if (!nfs_compare_fh(&file->f_handle, &lock->fh)) {
	123	mutex_lock(&file->f_mutex);
	124	nfserr = nlm_do_fopen(rqstp, file, mode);
	125	mutex_unlock(&file->f_mutex);
1da177e4	126	goto found;
7f024fcd	127	}
2dc6f19e	128	nlm_debug_print_fh("creating file for", &lock->fh);
1da177e4 LT	129
1da177e4 LT	130	nfserr = nlm_lck_denied_nolocks;
f8314dc6	131	file = kzalloc(sizeof(*file), GFP_KERNEL);
1da177e4	132	if (!file)
7f024fcd	133	goto out_free;
1da177e4	134
2dc6f19e	135	memcpy(&file->f_handle, &lock->fh, sizeof(struct nfs_fh));
89e63ef6	136	mutex_init(&file->f_mutex);
07ba8063	137	INIT_HLIST_NODE(&file->f_list);
68a2d76c	138	INIT_LIST_HEAD(&file->f_blocks);
1da177e4	139
7f024fcd BF	140	nfserr = nlm_do_fopen(rqstp, file, mode);
	141	if (nfserr)
	142	goto out_unlock;
1da177e4	143
07ba8063	144	hlist_add_head(&file->f_list, &nlm_files[hash]);
1da177e4 LT	145
	146	found:
	147	dprintk("lockd: found file %p (count %d)\n", file, file->f_count);
	148	*result = file;
	149	file->f_count++;
1da177e4 LT	150
1da177e4 LT	151	out_unlock:
353ab6e9	152	mutex_unlock(&nlm_file_mutex);
1da177e4 LT	153	return nfserr;
	154
	155	out_free:
	156	kfree(file);
1da177e4 LT	157	goto out_unlock;
	158	}
	159
	160	/*
	161	* Delete a file after having released all locks, blocks and shares
	162	*/
	163	static inline void
	164	nlm_delete_file(struct nlm_file *file)
	165	{
0bbacc40	166	nlm_debug_print_file("closing file", file);
07ba8063 OK	167	if (!hlist_unhashed(&file->f_list)) {
07ba8063 OK	168	hlist_del(&file->f_list);
7f024fcd BF	169	if (file->f_file[O_RDONLY])
	170	nlmsvc_ops->fclose(file->f_file[O_RDONLY]);
	171	if (file->f_file[O_WRONLY])
	172	nlmsvc_ops->fclose(file->f_file[O_WRONLY]);
07ba8063 OK	173	kfree(file);
	174	} else {
	175	printk(KERN_WARNING "lockd: attempt to release unknown file!\n");
1da177e4	176	}
1da177e4 LT	177	}
1da177e4 LT	178
aec15824	179	static int nlm_unlock_files(struct nlm_file *file, fl_owner_t owner)
7f024fcd BF	180	{
7f024fcd BF	181	struct file_lock lock;
7f024fcd	182
d19a7af7	183	locks_init_lock(&lock);
7f024fcd BF	184	lock.fl_type = F_UNLCK;
	185	lock.fl_start = 0;
	186	lock.fl_end = OFFSET_MAX;
aec15824	187	lock.fl_owner = owner;
6e7f90d1 BF	188	if (file->f_file[O_RDONLY] &&
	189	vfs_lock_file(file->f_file[O_RDONLY], F_SETLK, &lock, NULL))
	190	goto out_err;
	191	if (file->f_file[O_WRONLY] &&
	192	vfs_lock_file(file->f_file[O_WRONLY], F_SETLK, &lock, NULL))
	193	goto out_err;
7f024fcd	194	return 0;
6e7f90d1 BF	195	out_err:
	196	pr_warn("lockd: unlock failure in %s:%d\n", __FILE__, __LINE__);
	197	return 1;
7f024fcd BF	198	}
7f024fcd BF	199
1da177e4 LT	200	/*
	201	* Loop over all locks on the given file and perform the specified
	202	* action.
	203	*/
	204	static int
f2af793d OK	205	nlm_traverse_locks(struct nlm_host host, struct nlm_file file,
f2af793d OK	206	nlm_host_match_fn_t match)
1da177e4 LT	207	{
	208	struct inode *inode = nlmsvc_file_inode(file);
	209	struct file_lock *fl;
bd61e0a9	210	struct file_lock_context *flctx = inode->i_flctx;
1da177e4 LT	211	struct nlm_host *lockhost;
1da177e4 LT	212
bd61e0a9 JL	213	if (!flctx \|\| list_empty_careful(&flctx->flc_posix))
bd61e0a9 JL	214	return 0;
1da177e4 LT	215	again:
1da177e4 LT	216	file->f_locks = 0;
6109c850	217	spin_lock(&flctx->flc_lock);
bd61e0a9	218	list_for_each_entry(fl, &flctx->flc_posix, fl_list) {
7117bf3d	219	if (fl->fl_lmops != &nlmsvc_lock_operations)
1da177e4 LT	220	continue;
	221
	222	/* update current lock count */
	223	file->f_locks++;
f2af793d	224
89e0edfb	225	lockhost = ((struct nlm_lockowner *)fl->fl_owner)->host;
f2af793d	226	if (match(lockhost, host)) {
1da177e4	227
6109c850	228	spin_unlock(&flctx->flc_lock);
aec15824	229	if (nlm_unlock_files(file, fl->fl_owner))
1da177e4	230	return 1;
1da177e4 LT	231	goto again;
	232	}
	233	}
6109c850	234	spin_unlock(&flctx->flc_lock);
1da177e4 LT	235
	236	return 0;
	237	}
	238
17efa372 WC	239	static int
	240	nlmsvc_always_match(void dummy1, struct nlm_host dummy2)
	241	{
	242	return 1;
	243	}
	244
1da177e4	245	/*
f2af793d OK	246	* Inspect a single file
	247	*/
	248	static inline int
	249	nlm_inspect_file(struct nlm_host host, struct nlm_file file, nlm_host_match_fn_t match)
	250	{
	251	nlmsvc_traverse_blocks(host, file, match);
	252	nlmsvc_traverse_shares(host, file, match);
	253	return nlm_traverse_locks(host, file, match);
	254	}
	255
	256	/*
	257	* Quick check whether there are still any locks, blocks or
	258	* shares on a given file.
1da177e4 LT	259	*/
1da177e4 LT	260	static inline int
f2af793d	261	nlm_file_inuse(struct nlm_file *file)
1da177e4	262	{
f2af793d OK	263	struct inode *inode = nlmsvc_file_inode(file);
f2af793d OK	264	struct file_lock *fl;
bd61e0a9	265	struct file_lock_context *flctx = inode->i_flctx;
f2af793d OK	266
	267	if (file->f_count \|\| !list_empty(&file->f_blocks) \|\| file->f_shares)
	268	return 1;
	269
bd61e0a9	270	if (flctx && !list_empty_careful(&flctx->flc_posix)) {
6109c850	271	spin_lock(&flctx->flc_lock);
bd61e0a9 JL	272	list_for_each_entry(fl, &flctx->flc_posix, fl_list) {
bd61e0a9 JL	273	if (fl->fl_lmops == &nlmsvc_lock_operations) {
6109c850	274	spin_unlock(&flctx->flc_lock);
bd61e0a9 JL	275	return 1;
bd61e0a9 JL	276	}
763641d8	277	}
6109c850	278	spin_unlock(&flctx->flc_lock);
1da177e4	279	}
f2af793d OK	280	file->f_locks = 0;
f2af793d OK	281	return 0;
1da177e4 LT	282	}
1da177e4 LT	283
7f024fcd BF	284	static void nlm_close_files(struct nlm_file *file)
7f024fcd BF	285	{
1197eb59 JL	286	if (file->f_file[O_RDONLY])
	287	nlmsvc_ops->fclose(file->f_file[O_RDONLY]);
	288	if (file->f_file[O_WRONLY])
	289	nlmsvc_ops->fclose(file->f_file[O_WRONLY]);
7f024fcd BF	290	}
7f024fcd BF	291
1da177e4 LT	292	/*
	293	* Loop over all files in the file table.
	294	*/
	295	static int
17efa372 WC	296	nlm_traverse_files(void *data, nlm_host_match_fn_t match,
17efa372 WC	297	int (is_failover_file)(void data, struct nlm_file *file))
1da177e4	298	{
b67bfe0d	299	struct hlist_node *next;
07ba8063	300	struct nlm_file *file;
01df9c5e	301	int i, ret = 0;
1da177e4	302
353ab6e9	303	mutex_lock(&nlm_file_mutex);
1da177e4	304	for (i = 0; i < FILE_NRHASH; i++) {
b67bfe0d	305	hlist_for_each_entry_safe(file, next, &nlm_files[i], f_list) {
17efa372 WC	306	if (is_failover_file && !is_failover_file(data, file))
17efa372 WC	307	continue;
01df9c5e TM	308	file->f_count++;
	309	mutex_unlock(&nlm_file_mutex);
	310
1da177e4 LT	311	/* Traverse locks, blocks and shares of this file
1da177e4 LT	312	* and update file->f_locks count */
4373ea84	313	if (nlm_inspect_file(data, file, match))
01df9c5e	314	ret = 1;
1da177e4	315
01df9c5e TM	316	mutex_lock(&nlm_file_mutex);
01df9c5e TM	317	file->f_count--;
1da177e4	318	/* No more references to this file. Let go of it. */
68a2d76c	319	if (list_empty(&file->f_blocks) && !file->f_locks
1da177e4	320	&& !file->f_shares && !file->f_count) {
07ba8063	321	hlist_del(&file->f_list);
7f024fcd	322	nlm_close_files(file);
1da177e4	323	kfree(file);
1da177e4 LT	324	}
	325	}
	326	}
353ab6e9	327	mutex_unlock(&nlm_file_mutex);
01df9c5e	328	return ret;
1da177e4 LT	329	}
	330
	331	/*
	332	* Release file. If there are no more remote locks on this file,
	333	* close it and free the handle.
	334	*
	335	* Note that we can't do proper reference counting without major
	336	* contortions because the code in fs/locks.c creates, deletes and
	337	* splits locks without notification. Our only way is to walk the
	338	* entire lock list each time we remove a lock.
	339	*/
	340	void
	341	nlm_release_file(struct nlm_file *file)
	342	{
	343	dprintk("lockd: nlm_release_file(%p, ct = %d)\n",
	344	file, file->f_count);
	345
	346	/* Lock file table */
353ab6e9	347	mutex_lock(&nlm_file_mutex);
1da177e4 LT	348
1da177e4 LT	349	/* If there are no more locks etc, delete the file */
f2af793d OK	350	if (--file->f_count == 0 && !nlm_file_inuse(file))
f2af793d OK	351	nlm_delete_file(file);
1da177e4	352
353ab6e9	353	mutex_unlock(&nlm_file_mutex);
1da177e4 LT	354	}
1da177e4 LT	355
f2af793d OK	356	/*
	357	* Helpers function for resource traversal
	358	*
	359	* nlmsvc_mark_host:
b26411f8 SK	360	* used by the garbage collector; simply sets h_inuse only for those
b26411f8 SK	361	* hosts, which passed network check.
f2af793d OK	362	* Always returns 0.
	363	*
	364	* nlmsvc_same_host:
	365	* returns 1 iff the two hosts match. Used to release
	366	* all resources bound to a specific host.
	367	*
	368	* nlmsvc_is_client:
	369	* returns 1 iff the host is a client.
	370	* Used by nlmsvc_invalidate_all
	371	*/
b26411f8	372
f2af793d	373	static int
b26411f8	374	nlmsvc_mark_host(void data, struct nlm_host hint)
f2af793d	375	{
4373ea84 WC	376	struct nlm_host *host = data;
4373ea84 WC	377
b26411f8 SK	378	if ((hint->net == NULL) \|\|
	379	(host->net == hint->net))
	380	host->h_inuse = 1;
f2af793d OK	381	return 0;
	382	}
	383
	384	static int
4373ea84	385	nlmsvc_same_host(void data, struct nlm_host other)
f2af793d	386	{
4373ea84 WC	387	struct nlm_host *host = data;
4373ea84 WC	388
f2af793d OK	389	return host == other;
	390	}
	391
	392	static int
4373ea84	393	nlmsvc_is_client(void data, struct nlm_host dummy)
f2af793d	394	{
4373ea84 WC	395	struct nlm_host *host = data;
4373ea84 WC	396
4481d103 N	397	if (host->h_server) {
	398	/* we are destroying locks even though the client
	399	* hasn't asked us too, so don't unmonitor the
	400	* client
	401	*/
	402	if (host->h_nsmhandle)
	403	host->h_nsmhandle->sm_sticky = 1;
	404	return 1;
	405	} else
	406	return 0;
f2af793d OK	407	}
f2af793d OK	408
1da177e4 LT	409	/*
	410	* Mark all hosts that still hold resources
	411	*/
	412	void
b26411f8	413	nlmsvc_mark_resources(struct net *net)
1da177e4	414	{
b26411f8 SK	415	struct nlm_host hint;
b26411f8 SK	416
e919b076	417	dprintk("lockd: %s for net %x\n", __func__, net ? net->ns.inum : 0);
b26411f8 SK	418	hint.net = net;
b26411f8 SK	419	nlm_traverse_files(&hint, nlmsvc_mark_host, NULL);
1da177e4 LT	420	}
	421
	422	/*
	423	* Release all resources held by the given client
	424	*/
	425	void
	426	nlmsvc_free_host_resources(struct nlm_host *host)
	427	{
	428	dprintk("lockd: nlmsvc_free_host_resources\n");
	429
17efa372	430	if (nlm_traverse_files(host, nlmsvc_same_host, NULL)) {
1da177e4	431	printk(KERN_WARNING
f0737a39	432	"lockd: couldn't remove all locks held by %s\n",
1da177e4	433	host->h_name);
f0737a39 OK	434	BUG();
f0737a39 OK	435	}
1da177e4 LT	436	}
1da177e4 LT	437
367c8c7b CL	438	/**
	439	* nlmsvc_invalidate_all - remove all locks held for clients
	440	*
	441	* Release all locks held by NFS clients.
	442	*
1da177e4 LT	443	*/
	444	void
	445	nlmsvc_invalidate_all(void)
	446	{
367c8c7b	447	/*
f2af793d OK	448	* Previously, the code would call
	449	* nlmsvc_free_host_resources for each client in
	450	* turn, which is about as inefficient as it gets.
	451	* Now we just do it once in nlm_traverse_files.
	452	*/
17efa372 WC	453	nlm_traverse_files(NULL, nlmsvc_is_client, NULL);
	454	}
	455
7f024fcd	456
17efa372 WC	457	static int
	458	nlmsvc_match_sb(void datap, struct nlm_file file)
	459	{
	460	struct super_block *sb = datap;
	461
a81041b7	462	return sb == nlmsvc_file_inode(file)->i_sb;
17efa372 WC	463	}
17efa372 WC	464
367c8c7b CL	465	/**
	466	* nlmsvc_unlock_all_by_sb - release locks held on this file system
	467	* @sb: super block
	468	*
	469	* Release all locks held by clients accessing this file system.
	470	*/
17efa372 WC	471	int
	472	nlmsvc_unlock_all_by_sb(struct super_block *sb)
	473	{
	474	int ret;
	475
	476	ret = nlm_traverse_files(sb, nlmsvc_always_match, nlmsvc_match_sb);
	477	return ret ? -EIO : 0;
1da177e4	478	}
17efa372	479	EXPORT_SYMBOL_GPL(nlmsvc_unlock_all_by_sb);
4373ea84 WC	480
	481	static int
	482	nlmsvc_match_ip(void datap, struct nlm_host host)
	483	{
4516fc04	484	return rpc_cmp_addr(nlm_srcaddr(host), datap);
4373ea84 WC	485	}
4373ea84 WC	486
367c8c7b CL	487	/**
	488	* nlmsvc_unlock_all_by_ip - release local locks by IP address
	489	* @server_addr: server's IP address as seen by clients
	490	*
	491	* Release all locks held by clients accessing this host
	492	* via the passed in IP address.
	493	*/
4373ea84	494	int
367c8c7b	495	nlmsvc_unlock_all_by_ip(struct sockaddr *server_addr)
4373ea84 WC	496	{
4373ea84 WC	497	int ret;
4373ea84	498
367c8c7b CL	499	ret = nlm_traverse_files(server_addr, nlmsvc_match_ip, NULL);
367c8c7b CL	500	return ret ? -EIO : 0;
4373ea84 WC	501	}
4373ea84 WC	502	EXPORT_SYMBOL_GPL(nlmsvc_unlock_all_by_ip);