[linux-2.6-block.git] / fs / lockd / svcsubs.c

/*
 * 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 NFSD_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 = file_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 nlm_host	 *lockhost;

again:
	file->f_locks = 0;
	spin_lock(&inode->i_lock);
	for (fl = inode->i_flock; fl; fl = fl->fl_next) {
		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(&inode->i_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(&inode->i_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;

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

	spin_lock(&inode->i_lock);
	for (fl = inode->i_flock; fl; fl = fl->fl_next) {
		if (fl->fl_lmops == &nlmsvc_lock_operations) {
			spin_unlock(&inode->i_lock);
			return 1;
		}
	}
	spin_unlock(&inode->i_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: nlmsvc_mark_resources for net %p\n", net);
	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 == file->f_file->f_path.dentry->d_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
1da177e4 LT	1	/*
	2	* linux/fs/lockd/svcsubs.c
	3	*
	4	* Various support routines for the NLM server.
	5	*
	6	* Copyright (C) 1996, Olaf Kirch <okir@monad.swb.de>
	7	*/
	8
1da177e4 LT	9	#include <linux/types.h>
	10	#include <linux/string.h>
	11	#include <linux/time.h>
	12	#include <linux/in.h>
5a0e3ad6	13	#include <linux/slab.h>
353ab6e9	14	#include <linux/mutex.h>
1da177e4	15	#include <linux/sunrpc/svc.h>
5976687a	16	#include <linux/sunrpc/addr.h>
1da177e4 LT	17	#include <linux/lockd/lockd.h>
1da177e4 LT	18	#include <linux/lockd/share.h>
4373ea84 WC	19	#include <linux/module.h>
4373ea84 WC	20	#include <linux/mount.h>
9c69de4c	21	#include <uapi/linux/nfs2.h>
1da177e4 LT	22
	23	#define NLMDBG_FACILITY NLMDBG_SVCSUBS
	24
	25
	26	/*
	27	* Global file hash table
	28	*/
07ba8063	29	#define FILE_HASH_BITS 7
1da177e4	30	#define FILE_NRHASH (1<<FILE_HASH_BITS)
07ba8063	31	static struct hlist_head nlm_files[FILE_NRHASH];
353ab6e9	32	static DEFINE_MUTEX(nlm_file_mutex);
1da177e4	33
0bbacc40 CL	34	#ifdef NFSD_DEBUG
	35	static inline void nlm_debug_print_fh(char msg, struct nfs_fh f)
	36	{
	37	u32 fhp = (u32)f->data;
	38
	39	/* print the first 32 bytes of the fh */
	40	dprintk("lockd: %s (%08x %08x %08x %08x %08x %08x %08x %08x)\n",
	41	msg, fhp[0], fhp[1], fhp[2], fhp[3],
	42	fhp[4], fhp[5], fhp[6], fhp[7]);
	43	}
	44
	45	static inline void nlm_debug_print_file(char msg, struct nlm_file file)
	46	{
496ad9aa	47	struct inode *inode = file_inode(file->f_file);
0bbacc40 CL	48
	49	dprintk("lockd: %s %s/%ld\n",
	50	msg, inode->i_sb->s_id, inode->i_ino);
	51	}
	52	#else
	53	static inline void nlm_debug_print_fh(char msg, struct nfs_fh f)
	54	{
	55	return;
	56	}
	57
	58	static inline void nlm_debug_print_file(char msg, struct nlm_file file)
	59	{
	60	return;
	61	}
	62	#endif
	63
1da177e4 LT	64	static inline unsigned int file_hash(struct nfs_fh *f)
	65	{
	66	unsigned int tmp=0;
	67	int i;
	68	for (i=0; i<NFS2_FHSIZE;i++)
	69	tmp += f->data[i];
	70	return tmp & (FILE_NRHASH - 1);
	71	}
	72
	73	/*
	74	* Lookup file info. If it doesn't exist, create a file info struct
	75	* and open a (VFS) file for the given inode.
	76	*
	77	* FIXME:
	78	* Note that we open the file O_RDONLY even when creating write locks.
	79	* This is not quite right, but for now, we assume the client performs
	80	* the proper R/W checking.
	81	*/
52921e02	82	__be32
1da177e4 LT	83	nlm_lookup_file(struct svc_rqst rqstp, struct nlm_file *result,
	84	struct nfs_fh *f)
	85	{
	86	struct nlm_file *file;
	87	unsigned int hash;
52921e02	88	__be32 nfserr;
1da177e4	89
50431d94	90	nlm_debug_print_fh("nlm_lookup_file", f);
1da177e4 LT	91
	92	hash = file_hash(f);
	93
	94	/* Lock file table */
353ab6e9	95	mutex_lock(&nlm_file_mutex);
1da177e4	96
b67bfe0d	97	hlist_for_each_entry(file, &nlm_files[hash], f_list)
1da177e4 LT	98	if (!nfs_compare_fh(&file->f_handle, f))
	99	goto found;
	100
0bbacc40	101	nlm_debug_print_fh("creating file for", f);
1da177e4 LT	102
1da177e4 LT	103	nfserr = nlm_lck_denied_nolocks;
f8314dc6	104	file = kzalloc(sizeof(*file), GFP_KERNEL);
1da177e4 LT	105	if (!file)
	106	goto out_unlock;
	107
1da177e4	108	memcpy(&file->f_handle, f, sizeof(struct nfs_fh));
89e63ef6	109	mutex_init(&file->f_mutex);
07ba8063	110	INIT_HLIST_NODE(&file->f_list);
68a2d76c	111	INIT_LIST_HEAD(&file->f_blocks);
1da177e4 LT	112
	113	/* Open the file. Note that this must not sleep for too long, else
	114	* we would lock up lockd:-) So no NFS re-exports, folks.
	115	*
	116	* We have to make sure we have the right credential to open
	117	* the file.
	118	*/
	119	if ((nfserr = nlmsvc_ops->fopen(rqstp, f, &file->f_file)) != 0) {
f0737a39	120	dprintk("lockd: open failed (error %d)\n", nfserr);
1da177e4 LT	121	goto out_free;
	122	}
	123
07ba8063	124	hlist_add_head(&file->f_list, &nlm_files[hash]);
1da177e4 LT	125
	126	found:
	127	dprintk("lockd: found file %p (count %d)\n", file, file->f_count);
	128	*result = file;
	129	file->f_count++;
	130	nfserr = 0;
	131
	132	out_unlock:
353ab6e9	133	mutex_unlock(&nlm_file_mutex);
1da177e4 LT	134	return nfserr;
	135
	136	out_free:
	137	kfree(file);
1da177e4 LT	138	goto out_unlock;
	139	}
	140
	141	/*
	142	* Delete a file after having released all locks, blocks and shares
	143	*/
	144	static inline void
	145	nlm_delete_file(struct nlm_file *file)
	146	{
0bbacc40	147	nlm_debug_print_file("closing file", file);
07ba8063 OK	148	if (!hlist_unhashed(&file->f_list)) {
	149	hlist_del(&file->f_list);
	150	nlmsvc_ops->fclose(file->f_file);
	151	kfree(file);
	152	} else {
	153	printk(KERN_WARNING "lockd: attempt to release unknown file!\n");
1da177e4	154	}
1da177e4 LT	155	}
	156
	157	/*
	158	* Loop over all locks on the given file and perform the specified
	159	* action.
	160	*/
	161	static int
f2af793d OK	162	nlm_traverse_locks(struct nlm_host host, struct nlm_file file,
f2af793d OK	163	nlm_host_match_fn_t match)
1da177e4 LT	164	{
	165	struct inode *inode = nlmsvc_file_inode(file);
	166	struct file_lock *fl;
	167	struct nlm_host *lockhost;
	168
	169	again:
	170	file->f_locks = 0;
1c8c601a	171	spin_lock(&inode->i_lock);
1da177e4	172	for (fl = inode->i_flock; fl; fl = fl->fl_next) {
7117bf3d	173	if (fl->fl_lmops != &nlmsvc_lock_operations)
1da177e4 LT	174	continue;
	175
	176	/* update current lock count */
	177	file->f_locks++;
f2af793d	178
1da177e4	179	lockhost = (struct nlm_host *) fl->fl_owner;
f2af793d	180	if (match(lockhost, host)) {
1da177e4 LT	181	struct file_lock lock = *fl;
1da177e4 LT	182
1c8c601a	183	spin_unlock(&inode->i_lock);
1da177e4 LT	184	lock.fl_type = F_UNLCK;
	185	lock.fl_start = 0;
	186	lock.fl_end = OFFSET_MAX;
1a8322b2	187	if (vfs_lock_file(file->f_file, F_SETLK, &lock, NULL) < 0) {
1da177e4 LT	188	printk("lockd: unlock failure in %s:%d\n",
	189	__FILE__, __LINE__);
	190	return 1;
	191	}
	192	goto again;
	193	}
	194	}
1c8c601a	195	spin_unlock(&inode->i_lock);
1da177e4 LT	196
	197	return 0;
	198	}
	199
17efa372 WC	200	static int
	201	nlmsvc_always_match(void dummy1, struct nlm_host dummy2)
	202	{
	203	return 1;
	204	}
	205
1da177e4	206	/*
f2af793d OK	207	* Inspect a single file
	208	*/
	209	static inline int
	210	nlm_inspect_file(struct nlm_host host, struct nlm_file file, nlm_host_match_fn_t match)
	211	{
	212	nlmsvc_traverse_blocks(host, file, match);
	213	nlmsvc_traverse_shares(host, file, match);
	214	return nlm_traverse_locks(host, file, match);
	215	}
	216
	217	/*
	218	* Quick check whether there are still any locks, blocks or
	219	* shares on a given file.
1da177e4 LT	220	*/
1da177e4 LT	221	static inline int
f2af793d	222	nlm_file_inuse(struct nlm_file *file)
1da177e4	223	{
f2af793d OK	224	struct inode *inode = nlmsvc_file_inode(file);
	225	struct file_lock *fl;
	226
	227	if (file->f_count \|\| !list_empty(&file->f_blocks) \|\| file->f_shares)
	228	return 1;
	229
1c8c601a	230	spin_lock(&inode->i_lock);
f2af793d	231	for (fl = inode->i_flock; fl; fl = fl->fl_next) {
763641d8	232	if (fl->fl_lmops == &nlmsvc_lock_operations) {
1c8c601a	233	spin_unlock(&inode->i_lock);
1da177e4	234	return 1;
763641d8	235	}
1da177e4	236	}
1c8c601a	237	spin_unlock(&inode->i_lock);
f2af793d OK	238	file->f_locks = 0;
f2af793d OK	239	return 0;
1da177e4 LT	240	}
	241
	242	/*
	243	* Loop over all files in the file table.
	244	*/
	245	static int
17efa372 WC	246	nlm_traverse_files(void *data, nlm_host_match_fn_t match,
17efa372 WC	247	int (is_failover_file)(void data, struct nlm_file *file))
1da177e4	248	{
b67bfe0d	249	struct hlist_node *next;
07ba8063	250	struct nlm_file *file;
01df9c5e	251	int i, ret = 0;
1da177e4	252
353ab6e9	253	mutex_lock(&nlm_file_mutex);
1da177e4	254	for (i = 0; i < FILE_NRHASH; i++) {
b67bfe0d	255	hlist_for_each_entry_safe(file, next, &nlm_files[i], f_list) {
17efa372 WC	256	if (is_failover_file && !is_failover_file(data, file))
17efa372 WC	257	continue;
01df9c5e TM	258	file->f_count++;
	259	mutex_unlock(&nlm_file_mutex);
	260
1da177e4 LT	261	/* Traverse locks, blocks and shares of this file
1da177e4 LT	262	* and update file->f_locks count */
4373ea84	263	if (nlm_inspect_file(data, file, match))
01df9c5e	264	ret = 1;
1da177e4	265
01df9c5e TM	266	mutex_lock(&nlm_file_mutex);
01df9c5e TM	267	file->f_count--;
1da177e4	268	/* No more references to this file. Let go of it. */
68a2d76c	269	if (list_empty(&file->f_blocks) && !file->f_locks
1da177e4	270	&& !file->f_shares && !file->f_count) {
07ba8063	271	hlist_del(&file->f_list);
1da177e4 LT	272	nlmsvc_ops->fclose(file->f_file);
1da177e4 LT	273	kfree(file);
1da177e4 LT	274	}
	275	}
	276	}
353ab6e9	277	mutex_unlock(&nlm_file_mutex);
01df9c5e	278	return ret;
1da177e4 LT	279	}
	280
	281	/*
	282	* Release file. If there are no more remote locks on this file,
	283	* close it and free the handle.
	284	*
	285	* Note that we can't do proper reference counting without major
	286	* contortions because the code in fs/locks.c creates, deletes and
	287	* splits locks without notification. Our only way is to walk the
	288	* entire lock list each time we remove a lock.
	289	*/
	290	void
	291	nlm_release_file(struct nlm_file *file)
	292	{
	293	dprintk("lockd: nlm_release_file(%p, ct = %d)\n",
	294	file, file->f_count);
	295
	296	/* Lock file table */
353ab6e9	297	mutex_lock(&nlm_file_mutex);
1da177e4 LT	298
1da177e4 LT	299	/* If there are no more locks etc, delete the file */
f2af793d OK	300	if (--file->f_count == 0 && !nlm_file_inuse(file))
f2af793d OK	301	nlm_delete_file(file);
1da177e4	302
353ab6e9	303	mutex_unlock(&nlm_file_mutex);
1da177e4 LT	304	}
1da177e4 LT	305
f2af793d OK	306	/*
	307	* Helpers function for resource traversal
	308	*
	309	* nlmsvc_mark_host:
b26411f8 SK	310	* used by the garbage collector; simply sets h_inuse only for those
b26411f8 SK	311	* hosts, which passed network check.
f2af793d OK	312	* Always returns 0.
	313	*
	314	* nlmsvc_same_host:
	315	* returns 1 iff the two hosts match. Used to release
	316	* all resources bound to a specific host.
	317	*
	318	* nlmsvc_is_client:
	319	* returns 1 iff the host is a client.
	320	* Used by nlmsvc_invalidate_all
	321	*/
b26411f8	322
f2af793d	323	static int
b26411f8	324	nlmsvc_mark_host(void data, struct nlm_host hint)
f2af793d	325	{
4373ea84 WC	326	struct nlm_host *host = data;
4373ea84 WC	327
b26411f8 SK	328	if ((hint->net == NULL) \|\|
	329	(host->net == hint->net))
	330	host->h_inuse = 1;
f2af793d OK	331	return 0;
	332	}
	333
	334	static int
4373ea84	335	nlmsvc_same_host(void data, struct nlm_host other)
f2af793d	336	{
4373ea84 WC	337	struct nlm_host *host = data;
4373ea84 WC	338
f2af793d OK	339	return host == other;
	340	}
	341
	342	static int
4373ea84	343	nlmsvc_is_client(void data, struct nlm_host dummy)
f2af793d	344	{
4373ea84 WC	345	struct nlm_host *host = data;
4373ea84 WC	346
4481d103 N	347	if (host->h_server) {
	348	/* we are destroying locks even though the client
	349	* hasn't asked us too, so don't unmonitor the
	350	* client
	351	*/
	352	if (host->h_nsmhandle)
	353	host->h_nsmhandle->sm_sticky = 1;
	354	return 1;
	355	} else
	356	return 0;
f2af793d OK	357	}
f2af793d OK	358
1da177e4 LT	359	/*
	360	* Mark all hosts that still hold resources
	361	*/
	362	void
b26411f8	363	nlmsvc_mark_resources(struct net *net)
1da177e4	364	{
b26411f8 SK	365	struct nlm_host hint;
	366
	367	dprintk("lockd: nlmsvc_mark_resources for net %p\n", net);
	368	hint.net = net;
	369	nlm_traverse_files(&hint, nlmsvc_mark_host, NULL);
1da177e4 LT	370	}
	371
	372	/*
	373	* Release all resources held by the given client
	374	*/
	375	void
	376	nlmsvc_free_host_resources(struct nlm_host *host)
	377	{
	378	dprintk("lockd: nlmsvc_free_host_resources\n");
	379
17efa372	380	if (nlm_traverse_files(host, nlmsvc_same_host, NULL)) {
1da177e4	381	printk(KERN_WARNING
f0737a39	382	"lockd: couldn't remove all locks held by %s\n",
1da177e4	383	host->h_name);
f0737a39 OK	384	BUG();
f0737a39 OK	385	}
1da177e4 LT	386	}
1da177e4 LT	387
367c8c7b CL	388	/**
	389	* nlmsvc_invalidate_all - remove all locks held for clients
	390	*
	391	* Release all locks held by NFS clients.
	392	*
1da177e4 LT	393	*/
	394	void
	395	nlmsvc_invalidate_all(void)
	396	{
367c8c7b	397	/*
f2af793d OK	398	* Previously, the code would call
	399	* nlmsvc_free_host_resources for each client in
	400	* turn, which is about as inefficient as it gets.
	401	* Now we just do it once in nlm_traverse_files.
	402	*/
17efa372 WC	403	nlm_traverse_files(NULL, nlmsvc_is_client, NULL);
	404	}
	405
	406	static int
	407	nlmsvc_match_sb(void datap, struct nlm_file file)
	408	{
	409	struct super_block *sb = datap;
	410
d8c9584e	411	return sb == file->f_file->f_path.dentry->d_sb;
17efa372 WC	412	}
17efa372 WC	413
367c8c7b CL	414	/**
	415	* nlmsvc_unlock_all_by_sb - release locks held on this file system
	416	* @sb: super block
	417	*
	418	* Release all locks held by clients accessing this file system.
	419	*/
17efa372 WC	420	int
	421	nlmsvc_unlock_all_by_sb(struct super_block *sb)
	422	{
	423	int ret;
	424
	425	ret = nlm_traverse_files(sb, nlmsvc_always_match, nlmsvc_match_sb);
	426	return ret ? -EIO : 0;
1da177e4	427	}
17efa372	428	EXPORT_SYMBOL_GPL(nlmsvc_unlock_all_by_sb);
4373ea84 WC	429
	430	static int
	431	nlmsvc_match_ip(void datap, struct nlm_host host)
	432	{
4516fc04	433	return rpc_cmp_addr(nlm_srcaddr(host), datap);
4373ea84 WC	434	}
4373ea84 WC	435
367c8c7b CL	436	/**
	437	* nlmsvc_unlock_all_by_ip - release local locks by IP address
	438	* @server_addr: server's IP address as seen by clients
	439	*
	440	* Release all locks held by clients accessing this host
	441	* via the passed in IP address.
	442	*/
4373ea84	443	int
367c8c7b	444	nlmsvc_unlock_all_by_ip(struct sockaddr *server_addr)
4373ea84 WC	445	{
4373ea84 WC	446	int ret;
4373ea84	447
367c8c7b CL	448	ret = nlm_traverse_files(server_addr, nlmsvc_match_ip, NULL);
367c8c7b CL	449	return ret ? -EIO : 0;
4373ea84 WC	450	}
4373ea84 WC	451	EXPORT_SYMBOL_GPL(nlmsvc_unlock_all_by_ip);