[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/mutex.h>
#include <linux/sunrpc/svc.h>
#include <linux/sunrpc/clnt.h>
#include <linux/nfsd/nfsfh.h>
#include <linux/nfsd/export.h>
#include <linux/lockd/lockd.h>
#include <linux/lockd/share.h>
#include <linux/module.h>
#include <linux/mount.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->f_file->f_path.dentry->d_inode;

	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 hlist_node *pos;
	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, pos, &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;
	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;

			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;
		}
	}

	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;

	for (fl = inode->i_flock; fl; fl = fl->fl_next) {
		if (fl->fl_lmops == &nlmsvc_lock_operations)
			return 1;
	}
	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 *pos, *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, pos, 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.
 *	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 *dummy)
{
	struct nlm_host *host = data;

	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(void)
{
	dprintk("lockd: nlmsvc_mark_resources\n");
	nlm_traverse_files(NULL, 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.mnt->mnt_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>
353ab6e9	13	#include <linux/mutex.h>
1da177e4 LT	14	#include <linux/sunrpc/svc.h>
	15	#include <linux/sunrpc/clnt.h>
	16	#include <linux/nfsd/nfsfh.h>
	17	#include <linux/nfsd/export.h>
	18	#include <linux/lockd/lockd.h>
	19	#include <linux/lockd/share.h>
4373ea84 WC	20	#include <linux/module.h>
4373ea84 WC	21	#include <linux/mount.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	{
225a719f	47	struct inode *inode = file->f_file->f_path.dentry->d_inode;
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	{
07ba8063	86	struct hlist_node *pos;
1da177e4 LT	87	struct nlm_file *file;
1da177e4 LT	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
07ba8063	98	hlist_for_each_entry(file, pos, &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;
	168	struct nlm_host *lockhost;
	169
	170	again:
	171	file->f_locks = 0;
	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
1da177e4 LT	183	lock.fl_type = F_UNLCK;
	184	lock.fl_start = 0;
	185	lock.fl_end = OFFSET_MAX;
1a8322b2	186	if (vfs_lock_file(file->f_file, F_SETLK, &lock, NULL) < 0) {
1da177e4 LT	187	printk("lockd: unlock failure in %s:%d\n",
	188	__FILE__, __LINE__);
	189	return 1;
	190	}
	191	goto again;
	192	}
	193	}
	194
	195	return 0;
	196	}
	197
17efa372 WC	198	static int
	199	nlmsvc_always_match(void dummy1, struct nlm_host dummy2)
	200	{
	201	return 1;
	202	}
	203
1da177e4	204	/*
f2af793d OK	205	* Inspect a single file
	206	*/
	207	static inline int
	208	nlm_inspect_file(struct nlm_host host, struct nlm_file file, nlm_host_match_fn_t match)
	209	{
	210	nlmsvc_traverse_blocks(host, file, match);
	211	nlmsvc_traverse_shares(host, file, match);
	212	return nlm_traverse_locks(host, file, match);
	213	}
	214
	215	/*
	216	* Quick check whether there are still any locks, blocks or
	217	* shares on a given file.
1da177e4 LT	218	*/
1da177e4 LT	219	static inline int
f2af793d	220	nlm_file_inuse(struct nlm_file *file)
1da177e4	221	{
f2af793d OK	222	struct inode *inode = nlmsvc_file_inode(file);
	223	struct file_lock *fl;
	224
	225	if (file->f_count \|\| !list_empty(&file->f_blocks) \|\| file->f_shares)
	226	return 1;
	227
	228	for (fl = inode->i_flock; fl; fl = fl->fl_next) {
	229	if (fl->fl_lmops == &nlmsvc_lock_operations)
1da177e4	230	return 1;
1da177e4	231	}
f2af793d OK	232	file->f_locks = 0;
f2af793d OK	233	return 0;
1da177e4 LT	234	}
	235
	236	/*
	237	* Loop over all files in the file table.
	238	*/
	239	static int
17efa372 WC	240	nlm_traverse_files(void *data, nlm_host_match_fn_t match,
17efa372 WC	241	int (is_failover_file)(void data, struct nlm_file *file))
1da177e4	242	{
07ba8063 OK	243	struct hlist_node pos, next;
07ba8063 OK	244	struct nlm_file *file;
01df9c5e	245	int i, ret = 0;
1da177e4	246
353ab6e9	247	mutex_lock(&nlm_file_mutex);
1da177e4	248	for (i = 0; i < FILE_NRHASH; i++) {
07ba8063	249	hlist_for_each_entry_safe(file, pos, next, &nlm_files[i], f_list) {
17efa372 WC	250	if (is_failover_file && !is_failover_file(data, file))
17efa372 WC	251	continue;
01df9c5e TM	252	file->f_count++;
	253	mutex_unlock(&nlm_file_mutex);
	254
1da177e4 LT	255	/* Traverse locks, blocks and shares of this file
1da177e4 LT	256	* and update file->f_locks count */
4373ea84	257	if (nlm_inspect_file(data, file, match))
01df9c5e	258	ret = 1;
1da177e4	259
01df9c5e TM	260	mutex_lock(&nlm_file_mutex);
01df9c5e TM	261	file->f_count--;
1da177e4	262	/* No more references to this file. Let go of it. */
68a2d76c	263	if (list_empty(&file->f_blocks) && !file->f_locks
1da177e4	264	&& !file->f_shares && !file->f_count) {
07ba8063	265	hlist_del(&file->f_list);
1da177e4 LT	266	nlmsvc_ops->fclose(file->f_file);
1da177e4 LT	267	kfree(file);
1da177e4 LT	268	}
	269	}
	270	}
353ab6e9	271	mutex_unlock(&nlm_file_mutex);
01df9c5e	272	return ret;
1da177e4 LT	273	}
	274
	275	/*
	276	* Release file. If there are no more remote locks on this file,
	277	* close it and free the handle.
	278	*
	279	* Note that we can't do proper reference counting without major
	280	* contortions because the code in fs/locks.c creates, deletes and
	281	* splits locks without notification. Our only way is to walk the
	282	* entire lock list each time we remove a lock.
	283	*/
	284	void
	285	nlm_release_file(struct nlm_file *file)
	286	{
	287	dprintk("lockd: nlm_release_file(%p, ct = %d)\n",
	288	file, file->f_count);
	289
	290	/* Lock file table */
353ab6e9	291	mutex_lock(&nlm_file_mutex);
1da177e4 LT	292
1da177e4 LT	293	/* If there are no more locks etc, delete the file */
f2af793d OK	294	if (--file->f_count == 0 && !nlm_file_inuse(file))
f2af793d OK	295	nlm_delete_file(file);
1da177e4	296
353ab6e9	297	mutex_unlock(&nlm_file_mutex);
1da177e4 LT	298	}
1da177e4 LT	299
f2af793d OK	300	/*
	301	* Helpers function for resource traversal
	302	*
	303	* nlmsvc_mark_host:
	304	* used by the garbage collector; simply sets h_inuse.
	305	* Always returns 0.
	306	*
	307	* nlmsvc_same_host:
	308	* returns 1 iff the two hosts match. Used to release
	309	* all resources bound to a specific host.
	310	*
	311	* nlmsvc_is_client:
	312	* returns 1 iff the host is a client.
	313	* Used by nlmsvc_invalidate_all
	314	*/
	315	static int
4373ea84	316	nlmsvc_mark_host(void data, struct nlm_host dummy)
f2af793d	317	{
4373ea84 WC	318	struct nlm_host *host = data;
4373ea84 WC	319
f2af793d OK	320	host->h_inuse = 1;
	321	return 0;
	322	}
	323
	324	static int
4373ea84	325	nlmsvc_same_host(void data, struct nlm_host other)
f2af793d	326	{
4373ea84 WC	327	struct nlm_host *host = data;
4373ea84 WC	328
f2af793d OK	329	return host == other;
	330	}
	331
	332	static int
4373ea84	333	nlmsvc_is_client(void data, struct nlm_host dummy)
f2af793d	334	{
4373ea84 WC	335	struct nlm_host *host = data;
4373ea84 WC	336
4481d103 N	337	if (host->h_server) {
	338	/* we are destroying locks even though the client
	339	* hasn't asked us too, so don't unmonitor the
	340	* client
	341	*/
	342	if (host->h_nsmhandle)
	343	host->h_nsmhandle->sm_sticky = 1;
	344	return 1;
	345	} else
	346	return 0;
f2af793d OK	347	}
f2af793d OK	348
1da177e4 LT	349	/*
	350	* Mark all hosts that still hold resources
	351	*/
	352	void
	353	nlmsvc_mark_resources(void)
	354	{
	355	dprintk("lockd: nlmsvc_mark_resources\n");
17efa372	356	nlm_traverse_files(NULL, nlmsvc_mark_host, NULL);
1da177e4 LT	357	}
	358
	359	/*
	360	* Release all resources held by the given client
	361	*/
	362	void
	363	nlmsvc_free_host_resources(struct nlm_host *host)
	364	{
	365	dprintk("lockd: nlmsvc_free_host_resources\n");
	366
17efa372	367	if (nlm_traverse_files(host, nlmsvc_same_host, NULL)) {
1da177e4	368	printk(KERN_WARNING
f0737a39	369	"lockd: couldn't remove all locks held by %s\n",
1da177e4	370	host->h_name);
f0737a39 OK	371	BUG();
f0737a39 OK	372	}
1da177e4 LT	373	}
1da177e4 LT	374
367c8c7b CL	375	/**
	376	* nlmsvc_invalidate_all - remove all locks held for clients
	377	*
	378	* Release all locks held by NFS clients.
	379	*
1da177e4 LT	380	*/
	381	void
	382	nlmsvc_invalidate_all(void)
	383	{
367c8c7b	384	/*
f2af793d OK	385	* Previously, the code would call
	386	* nlmsvc_free_host_resources for each client in
	387	* turn, which is about as inefficient as it gets.
	388	* Now we just do it once in nlm_traverse_files.
	389	*/
17efa372 WC	390	nlm_traverse_files(NULL, nlmsvc_is_client, NULL);
	391	}
	392
	393	static int
	394	nlmsvc_match_sb(void datap, struct nlm_file file)
	395	{
	396	struct super_block *sb = datap;
	397
	398	return sb == file->f_file->f_path.mnt->mnt_sb;
	399	}
	400
367c8c7b CL	401	/**
	402	* nlmsvc_unlock_all_by_sb - release locks held on this file system
	403	* @sb: super block
	404	*
	405	* Release all locks held by clients accessing this file system.
	406	*/
17efa372 WC	407	int
	408	nlmsvc_unlock_all_by_sb(struct super_block *sb)
	409	{
	410	int ret;
	411
	412	ret = nlm_traverse_files(sb, nlmsvc_always_match, nlmsvc_match_sb);
	413	return ret ? -EIO : 0;
1da177e4	414	}
17efa372	415	EXPORT_SYMBOL_GPL(nlmsvc_unlock_all_by_sb);
4373ea84 WC	416
	417	static int
	418	nlmsvc_match_ip(void datap, struct nlm_host host)
	419	{
4516fc04	420	return rpc_cmp_addr(nlm_srcaddr(host), datap);
4373ea84 WC	421	}
4373ea84 WC	422
367c8c7b CL	423	/**
	424	* nlmsvc_unlock_all_by_ip - release local locks by IP address
	425	* @server_addr: server's IP address as seen by clients
	426	*
	427	* Release all locks held by clients accessing this host
	428	* via the passed in IP address.
	429	*/
4373ea84	430	int
367c8c7b	431	nlmsvc_unlock_all_by_ip(struct sockaddr *server_addr)
4373ea84 WC	432	{
4373ea84 WC	433	int ret;
4373ea84	434
367c8c7b CL	435	ret = nlm_traverse_files(server_addr, nlmsvc_match_ip, NULL);
367c8c7b CL	436	return ret ? -EIO : 0;
4373ea84 WC	437	}
4373ea84 WC	438	EXPORT_SYMBOL_GPL(nlmsvc_unlock_all_by_ip);