[linux-block.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 = locks_inode(file->f_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);
}

/*
 * Lookup file info. If it doesn't exist, create a file info struct
 * and open a (VFS) file for the given inode.
 *
 * FIXME:
 * Note that we open the file O_RDONLY even when creating write locks.
 * This is not quite right, but for now, we assume the client performs
 * the proper R/W checking.
 */
__be32
nlm_lookup_file(struct svc_rqst *rqstp, struct nlm_file **result,
					struct nfs_fh *f)
{
	struct nlm_file	*file;
	unsigned int	hash;
	__be32		nfserr;

	nlm_debug_print_fh("nlm_lookup_file", f);

	hash = file_hash(f);

	/* 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, f))
			goto found;

	nlm_debug_print_fh("creating file for", f);

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

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

	/* Open the file. Note that this must not sleep for too long, else
	 * we would lock up lockd:-) So no NFS re-exports, folks.
	 *
	 * We have to make sure we have the right credential to open
	 * the file.
	 */
	if ((nfserr = nlmsvc_ops->fopen(rqstp, f, &file->f_file)) != 0) {
		dprintk("lockd: open failed (error %d)\n", nfserr);
		goto out_free;
	}

	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++;
	nfserr = 0;

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);
		nlmsvc_ops->fclose(file->f_file);
		kfree(file);
	} else {
		printk(KERN_WARNING "lockd: attempt to release unknown file!\n");
	}
}

/*
 * 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_host *) fl->fl_owner;
		if (match(lockhost, host)) {
			struct file_lock lock = *fl;

			spin_unlock(&flctx->flc_lock);
			lock.fl_type  = F_UNLCK;
			lock.fl_start = 0;
			lock.fl_end   = OFFSET_MAX;
			if (vfs_lock_file(file->f_file, F_SETLK, &lock, NULL) < 0) {
				printk("lockd: unlock failure in %s:%d\n",
						__FILE__, __LINE__);
				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;
}

/*
 * 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);
				nlmsvc_ops->fclose(file->f_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 == locks_inode(file->f_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	{
64bed6cb	48	struct inode *inode = locks_inode(file->f_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
	74	/*
	75	* Lookup file info. If it doesn't exist, create a file info struct
	76	* and open a (VFS) file for the given inode.
	77	*
	78	* FIXME:
	79	* Note that we open the file O_RDONLY even when creating write locks.
	80	* This is not quite right, but for now, we assume the client performs
	81	* the proper R/W checking.
	82	*/
52921e02	83	__be32
1da177e4 LT	84	nlm_lookup_file(struct svc_rqst rqstp, struct nlm_file *result,
	85	struct nfs_fh *f)
	86	{
	87	struct nlm_file *file;
	88	unsigned int hash;
52921e02	89	__be32 nfserr;
1da177e4	90
50431d94	91	nlm_debug_print_fh("nlm_lookup_file", f);
1da177e4 LT	92
	93	hash = file_hash(f);
	94
	95	/* Lock file table */
353ab6e9	96	mutex_lock(&nlm_file_mutex);
1da177e4	97
b67bfe0d	98	hlist_for_each_entry(file, &nlm_files[hash], f_list)
1da177e4 LT	99	if (!nfs_compare_fh(&file->f_handle, f))
	100	goto found;
	101
0bbacc40	102	nlm_debug_print_fh("creating file for", f);
1da177e4 LT	103
1da177e4 LT	104	nfserr = nlm_lck_denied_nolocks;
f8314dc6	105	file = kzalloc(sizeof(*file), GFP_KERNEL);
1da177e4 LT	106	if (!file)
	107	goto out_unlock;
	108
1da177e4	109	memcpy(&file->f_handle, f, sizeof(struct nfs_fh));
89e63ef6	110	mutex_init(&file->f_mutex);
07ba8063	111	INIT_HLIST_NODE(&file->f_list);
68a2d76c	112	INIT_LIST_HEAD(&file->f_blocks);
1da177e4 LT	113
	114	/* Open the file. Note that this must not sleep for too long, else
	115	* we would lock up lockd:-) So no NFS re-exports, folks.
	116	*
	117	* We have to make sure we have the right credential to open
	118	* the file.
	119	*/
	120	if ((nfserr = nlmsvc_ops->fopen(rqstp, f, &file->f_file)) != 0) {
f0737a39	121	dprintk("lockd: open failed (error %d)\n", nfserr);
1da177e4 LT	122	goto out_free;
	123	}
	124
07ba8063	125	hlist_add_head(&file->f_list, &nlm_files[hash]);
1da177e4 LT	126
	127	found:
	128	dprintk("lockd: found file %p (count %d)\n", file, file->f_count);
	129	*result = file;
	130	file->f_count++;
	131	nfserr = 0;
	132
	133	out_unlock:
353ab6e9	134	mutex_unlock(&nlm_file_mutex);
1da177e4 LT	135	return nfserr;
	136
	137	out_free:
	138	kfree(file);
1da177e4 LT	139	goto out_unlock;
	140	}
	141
	142	/*
	143	* Delete a file after having released all locks, blocks and shares
	144	*/
	145	static inline void
	146	nlm_delete_file(struct nlm_file *file)
	147	{
0bbacc40	148	nlm_debug_print_file("closing file", file);
07ba8063 OK	149	if (!hlist_unhashed(&file->f_list)) {
	150	hlist_del(&file->f_list);
	151	nlmsvc_ops->fclose(file->f_file);
	152	kfree(file);
	153	} else {
	154	printk(KERN_WARNING "lockd: attempt to release unknown file!\n");
1da177e4	155	}
1da177e4 LT	156	}
	157
	158	/*
	159	* Loop over all locks on the given file and perform the specified
	160	* action.
	161	*/
	162	static int
f2af793d OK	163	nlm_traverse_locks(struct nlm_host host, struct nlm_file file,
f2af793d OK	164	nlm_host_match_fn_t match)
1da177e4 LT	165	{
	166	struct inode *inode = nlmsvc_file_inode(file);
	167	struct file_lock *fl;
bd61e0a9	168	struct file_lock_context *flctx = inode->i_flctx;
1da177e4 LT	169	struct nlm_host *lockhost;
1da177e4 LT	170
bd61e0a9 JL	171	if (!flctx \|\| list_empty_careful(&flctx->flc_posix))
bd61e0a9 JL	172	return 0;
1da177e4 LT	173	again:
1da177e4 LT	174	file->f_locks = 0;
6109c850	175	spin_lock(&flctx->flc_lock);
bd61e0a9	176	list_for_each_entry(fl, &flctx->flc_posix, fl_list) {
7117bf3d	177	if (fl->fl_lmops != &nlmsvc_lock_operations)
1da177e4 LT	178	continue;
	179
	180	/* update current lock count */
	181	file->f_locks++;
f2af793d	182
1da177e4	183	lockhost = (struct nlm_host *) fl->fl_owner;
f2af793d	184	if (match(lockhost, host)) {
1da177e4 LT	185	struct file_lock lock = *fl;
1da177e4 LT	186
6109c850	187	spin_unlock(&flctx->flc_lock);
1da177e4 LT	188	lock.fl_type = F_UNLCK;
	189	lock.fl_start = 0;
	190	lock.fl_end = OFFSET_MAX;
1a8322b2	191	if (vfs_lock_file(file->f_file, F_SETLK, &lock, NULL) < 0) {
1da177e4 LT	192	printk("lockd: unlock failure in %s:%d\n",
	193	__FILE__, __LINE__);
	194	return 1;
	195	}
	196	goto again;
	197	}
	198	}
6109c850	199	spin_unlock(&flctx->flc_lock);
1da177e4 LT	200
	201	return 0;
	202	}
	203
17efa372 WC	204	static int
	205	nlmsvc_always_match(void dummy1, struct nlm_host dummy2)
	206	{
	207	return 1;
	208	}
	209
1da177e4	210	/*
f2af793d OK	211	* Inspect a single file
	212	*/
	213	static inline int
	214	nlm_inspect_file(struct nlm_host host, struct nlm_file file, nlm_host_match_fn_t match)
	215	{
	216	nlmsvc_traverse_blocks(host, file, match);
	217	nlmsvc_traverse_shares(host, file, match);
	218	return nlm_traverse_locks(host, file, match);
	219	}
	220
	221	/*
	222	* Quick check whether there are still any locks, blocks or
	223	* shares on a given file.
1da177e4 LT	224	*/
1da177e4 LT	225	static inline int
f2af793d	226	nlm_file_inuse(struct nlm_file *file)
1da177e4	227	{
f2af793d OK	228	struct inode *inode = nlmsvc_file_inode(file);
f2af793d OK	229	struct file_lock *fl;
bd61e0a9	230	struct file_lock_context *flctx = inode->i_flctx;
f2af793d OK	231
	232	if (file->f_count \|\| !list_empty(&file->f_blocks) \|\| file->f_shares)
	233	return 1;
	234
bd61e0a9	235	if (flctx && !list_empty_careful(&flctx->flc_posix)) {
6109c850	236	spin_lock(&flctx->flc_lock);
bd61e0a9 JL	237	list_for_each_entry(fl, &flctx->flc_posix, fl_list) {
bd61e0a9 JL	238	if (fl->fl_lmops == &nlmsvc_lock_operations) {
6109c850	239	spin_unlock(&flctx->flc_lock);
bd61e0a9 JL	240	return 1;
bd61e0a9 JL	241	}
763641d8	242	}
6109c850	243	spin_unlock(&flctx->flc_lock);
1da177e4	244	}
f2af793d OK	245	file->f_locks = 0;
f2af793d OK	246	return 0;
1da177e4 LT	247	}
	248
	249	/*
	250	* Loop over all files in the file table.
	251	*/
	252	static int
17efa372 WC	253	nlm_traverse_files(void *data, nlm_host_match_fn_t match,
17efa372 WC	254	int (is_failover_file)(void data, struct nlm_file *file))
1da177e4	255	{
b67bfe0d	256	struct hlist_node *next;
07ba8063	257	struct nlm_file *file;
01df9c5e	258	int i, ret = 0;
1da177e4	259
353ab6e9	260	mutex_lock(&nlm_file_mutex);
1da177e4	261	for (i = 0; i < FILE_NRHASH; i++) {
b67bfe0d	262	hlist_for_each_entry_safe(file, next, &nlm_files[i], f_list) {
17efa372 WC	263	if (is_failover_file && !is_failover_file(data, file))
17efa372 WC	264	continue;
01df9c5e TM	265	file->f_count++;
	266	mutex_unlock(&nlm_file_mutex);
	267
1da177e4 LT	268	/* Traverse locks, blocks and shares of this file
1da177e4 LT	269	* and update file->f_locks count */
4373ea84	270	if (nlm_inspect_file(data, file, match))
01df9c5e	271	ret = 1;
1da177e4	272
01df9c5e TM	273	mutex_lock(&nlm_file_mutex);
01df9c5e TM	274	file->f_count--;
1da177e4	275	/* No more references to this file. Let go of it. */
68a2d76c	276	if (list_empty(&file->f_blocks) && !file->f_locks
1da177e4	277	&& !file->f_shares && !file->f_count) {
07ba8063	278	hlist_del(&file->f_list);
1da177e4 LT	279	nlmsvc_ops->fclose(file->f_file);
1da177e4 LT	280	kfree(file);
1da177e4 LT	281	}
	282	}
	283	}
353ab6e9	284	mutex_unlock(&nlm_file_mutex);
01df9c5e	285	return ret;
1da177e4 LT	286	}
	287
	288	/*
	289	* Release file. If there are no more remote locks on this file,
	290	* close it and free the handle.
	291	*
	292	* Note that we can't do proper reference counting without major
	293	* contortions because the code in fs/locks.c creates, deletes and
	294	* splits locks without notification. Our only way is to walk the
	295	* entire lock list each time we remove a lock.
	296	*/
	297	void
	298	nlm_release_file(struct nlm_file *file)
	299	{
	300	dprintk("lockd: nlm_release_file(%p, ct = %d)\n",
	301	file, file->f_count);
	302
	303	/* Lock file table */
353ab6e9	304	mutex_lock(&nlm_file_mutex);
1da177e4 LT	305
1da177e4 LT	306	/* If there are no more locks etc, delete the file */
f2af793d OK	307	if (--file->f_count == 0 && !nlm_file_inuse(file))
f2af793d OK	308	nlm_delete_file(file);
1da177e4	309
353ab6e9	310	mutex_unlock(&nlm_file_mutex);
1da177e4 LT	311	}
1da177e4 LT	312
f2af793d OK	313	/*
	314	* Helpers function for resource traversal
	315	*
	316	* nlmsvc_mark_host:
b26411f8 SK	317	* used by the garbage collector; simply sets h_inuse only for those
b26411f8 SK	318	* hosts, which passed network check.
f2af793d OK	319	* Always returns 0.
	320	*
	321	* nlmsvc_same_host:
	322	* returns 1 iff the two hosts match. Used to release
	323	* all resources bound to a specific host.
	324	*
	325	* nlmsvc_is_client:
	326	* returns 1 iff the host is a client.
	327	* Used by nlmsvc_invalidate_all
	328	*/
b26411f8	329
f2af793d	330	static int
b26411f8	331	nlmsvc_mark_host(void data, struct nlm_host hint)
f2af793d	332	{
4373ea84 WC	333	struct nlm_host *host = data;
4373ea84 WC	334
b26411f8 SK	335	if ((hint->net == NULL) \|\|
	336	(host->net == hint->net))
	337	host->h_inuse = 1;
f2af793d OK	338	return 0;
	339	}
	340
	341	static int
4373ea84	342	nlmsvc_same_host(void data, struct nlm_host other)
f2af793d	343	{
4373ea84 WC	344	struct nlm_host *host = data;
4373ea84 WC	345
f2af793d OK	346	return host == other;
	347	}
	348
	349	static int
4373ea84	350	nlmsvc_is_client(void data, struct nlm_host dummy)
f2af793d	351	{
4373ea84 WC	352	struct nlm_host *host = data;
4373ea84 WC	353
4481d103 N	354	if (host->h_server) {
	355	/* we are destroying locks even though the client
	356	* hasn't asked us too, so don't unmonitor the
	357	* client
	358	*/
	359	if (host->h_nsmhandle)
	360	host->h_nsmhandle->sm_sticky = 1;
	361	return 1;
	362	} else
	363	return 0;
f2af793d OK	364	}
f2af793d OK	365
1da177e4 LT	366	/*
	367	* Mark all hosts that still hold resources
	368	*/
	369	void
b26411f8	370	nlmsvc_mark_resources(struct net *net)
1da177e4	371	{
b26411f8 SK	372	struct nlm_host hint;
b26411f8 SK	373
e919b076	374	dprintk("lockd: %s for net %x\n", __func__, net ? net->ns.inum : 0);
b26411f8 SK	375	hint.net = net;
b26411f8 SK	376	nlm_traverse_files(&hint, nlmsvc_mark_host, NULL);
1da177e4 LT	377	}
	378
	379	/*
	380	* Release all resources held by the given client
	381	*/
	382	void
	383	nlmsvc_free_host_resources(struct nlm_host *host)
	384	{
	385	dprintk("lockd: nlmsvc_free_host_resources\n");
	386
17efa372	387	if (nlm_traverse_files(host, nlmsvc_same_host, NULL)) {
1da177e4	388	printk(KERN_WARNING
f0737a39	389	"lockd: couldn't remove all locks held by %s\n",
1da177e4	390	host->h_name);
f0737a39 OK	391	BUG();
f0737a39 OK	392	}
1da177e4 LT	393	}
1da177e4 LT	394
367c8c7b CL	395	/**
	396	* nlmsvc_invalidate_all - remove all locks held for clients
	397	*
	398	* Release all locks held by NFS clients.
	399	*
1da177e4 LT	400	*/
	401	void
	402	nlmsvc_invalidate_all(void)
	403	{
367c8c7b	404	/*
f2af793d OK	405	* Previously, the code would call
	406	* nlmsvc_free_host_resources for each client in
	407	* turn, which is about as inefficient as it gets.
	408	* Now we just do it once in nlm_traverse_files.
	409	*/
17efa372 WC	410	nlm_traverse_files(NULL, nlmsvc_is_client, NULL);
	411	}
	412
	413	static int
	414	nlmsvc_match_sb(void datap, struct nlm_file file)
	415	{
	416	struct super_block *sb = datap;
	417
64bed6cb	418	return sb == locks_inode(file->f_file)->i_sb;
17efa372 WC	419	}
17efa372 WC	420
367c8c7b CL	421	/**
	422	* nlmsvc_unlock_all_by_sb - release locks held on this file system
	423	* @sb: super block
	424	*
	425	* Release all locks held by clients accessing this file system.
	426	*/
17efa372 WC	427	int
	428	nlmsvc_unlock_all_by_sb(struct super_block *sb)
	429	{
	430	int ret;
	431
	432	ret = nlm_traverse_files(sb, nlmsvc_always_match, nlmsvc_match_sb);
	433	return ret ? -EIO : 0;
1da177e4	434	}
17efa372	435	EXPORT_SYMBOL_GPL(nlmsvc_unlock_all_by_sb);
4373ea84 WC	436
	437	static int
	438	nlmsvc_match_ip(void datap, struct nlm_host host)
	439	{
4516fc04	440	return rpc_cmp_addr(nlm_srcaddr(host), datap);
4373ea84 WC	441	}
4373ea84 WC	442
367c8c7b CL	443	/**
	444	* nlmsvc_unlock_all_by_ip - release local locks by IP address
	445	* @server_addr: server's IP address as seen by clients
	446	*
	447	* Release all locks held by clients accessing this host
	448	* via the passed in IP address.
	449	*/
4373ea84	450	int
367c8c7b	451	nlmsvc_unlock_all_by_ip(struct sockaddr *server_addr)
4373ea84 WC	452	{
4373ea84 WC	453	int ret;
4373ea84	454
367c8c7b CL	455	ret = nlm_traverse_files(server_addr, nlmsvc_match_ip, NULL);
367c8c7b CL	456	return ret ? -EIO : 0;
4373ea84 WC	457	}
4373ea84 WC	458	EXPORT_SYMBOL_GPL(nlmsvc_unlock_all_by_ip);