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v4.6
 
  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
  9#include <linux/types.h>
 10#include <linux/string.h>
 11#include <linux/time.h>
 12#include <linux/in.h>
 13#include <linux/slab.h>
 14#include <linux/mutex.h>
 15#include <linux/sunrpc/svc.h>
 16#include <linux/sunrpc/addr.h>
 17#include <linux/lockd/lockd.h>
 18#include <linux/lockd/share.h>
 19#include <linux/module.h>
 20#include <linux/mount.h>
 21#include <uapi/linux/nfs2.h>
 22
 23#define NLMDBG_FACILITY		NLMDBG_SVCSUBS
 24
 25
 26/*
 27 * Global file hash table
 28 */
 29#define FILE_HASH_BITS		7
 30#define FILE_NRHASH		(1<<FILE_HASH_BITS)
 31static struct hlist_head	nlm_files[FILE_NRHASH];
 32static DEFINE_MUTEX(nlm_file_mutex);
 33
 34#ifdef CONFIG_SUNRPC_DEBUG
 35static 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
 45static inline void nlm_debug_print_file(char *msg, struct nlm_file *file)
 46{
 47	struct inode *inode = file_inode(file->f_file);
 48
 49	dprintk("lockd: %s %s/%ld\n",
 50		msg, inode->i_sb->s_id, inode->i_ino);
 51}
 52#else
 53static inline void nlm_debug_print_fh(char *msg, struct nfs_fh *f)
 54{
 55	return;
 56}
 57
 58static inline void nlm_debug_print_file(char *msg, struct nlm_file *file)
 59{
 60	return;
 61}
 62#endif
 63
 64static 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 */
 82__be32
 83nlm_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;
 88	__be32		nfserr;
 89
 90	nlm_debug_print_fh("nlm_lookup_file", f);
 91
 92	hash = file_hash(f);
 93
 94	/* Lock file table */
 95	mutex_lock(&nlm_file_mutex);
 96
 97	hlist_for_each_entry(file, &nlm_files[hash], f_list)
 98		if (!nfs_compare_fh(&file->f_handle, f))
 99			goto found;
100
101	nlm_debug_print_fh("creating file for", f);
102
103	nfserr = nlm_lck_denied_nolocks;
104	file = kzalloc(sizeof(*file), GFP_KERNEL);
105	if (!file)
106		goto out_unlock;
107
108	memcpy(&file->f_handle, f, sizeof(struct nfs_fh));
109	mutex_init(&file->f_mutex);
110	INIT_HLIST_NODE(&file->f_list);
111	INIT_LIST_HEAD(&file->f_blocks);
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) {
120		dprintk("lockd: open failed (error %d)\n", nfserr);
121		goto out_free;
122	}
123
124	hlist_add_head(&file->f_list, &nlm_files[hash]);
125
126found:
127	dprintk("lockd: found file %p (count %d)\n", file, file->f_count);
128	*result = file;
129	file->f_count++;
130	nfserr = 0;
131
132out_unlock:
133	mutex_unlock(&nlm_file_mutex);
134	return nfserr;
135
136out_free:
137	kfree(file);
138	goto out_unlock;
139}
140
141/*
142 * Delete a file after having released all locks, blocks and shares
143 */
144static inline void
145nlm_delete_file(struct nlm_file *file)
146{
147	nlm_debug_print_file("closing file", file);
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");
154	}
155}
156
157/*
158 * Loop over all locks on the given file and perform the specified
159 * action.
160 */
161static int
162nlm_traverse_locks(struct nlm_host *host, struct nlm_file *file,
163			nlm_host_match_fn_t match)
164{
165	struct inode	 *inode = nlmsvc_file_inode(file);
166	struct file_lock *fl;
167	struct file_lock_context *flctx = inode->i_flctx;
168	struct nlm_host	 *lockhost;
169
170	if (!flctx || list_empty_careful(&flctx->flc_posix))
171		return 0;
172again:
173	file->f_locks = 0;
174	spin_lock(&flctx->flc_lock);
175	list_for_each_entry(fl, &flctx->flc_posix, fl_list) {
176		if (fl->fl_lmops != &nlmsvc_lock_operations)
177			continue;
178
179		/* update current lock count */
180		file->f_locks++;
181
182		lockhost = (struct nlm_host *) fl->fl_owner;
183		if (match(lockhost, host)) {
184			struct file_lock lock = *fl;
185
186			spin_unlock(&flctx->flc_lock);
187			lock.fl_type  = F_UNLCK;
188			lock.fl_start = 0;
189			lock.fl_end   = OFFSET_MAX;
190			if (vfs_lock_file(file->f_file, F_SETLK, &lock, NULL) < 0) {
191				printk("lockd: unlock failure in %s:%d\n",
192						__FILE__, __LINE__);
193				return 1;
194			}
195			goto again;
196		}
197	}
198	spin_unlock(&flctx->flc_lock);
199
200	return 0;
201}
202
203static int
204nlmsvc_always_match(void *dummy1, struct nlm_host *dummy2)
205{
206	return 1;
207}
208
209/*
210 * Inspect a single file
211 */
212static inline int
213nlm_inspect_file(struct nlm_host *host, struct nlm_file *file, nlm_host_match_fn_t match)
214{
215	nlmsvc_traverse_blocks(host, file, match);
216	nlmsvc_traverse_shares(host, file, match);
217	return nlm_traverse_locks(host, file, match);
218}
219
220/*
221 * Quick check whether there are still any locks, blocks or
222 * shares on a given file.
223 */
224static inline int
225nlm_file_inuse(struct nlm_file *file)
226{
227	struct inode	 *inode = nlmsvc_file_inode(file);
228	struct file_lock *fl;
229	struct file_lock_context *flctx = inode->i_flctx;
230
231	if (file->f_count || !list_empty(&file->f_blocks) || file->f_shares)
232		return 1;
233
234	if (flctx && !list_empty_careful(&flctx->flc_posix)) {
235		spin_lock(&flctx->flc_lock);
236		list_for_each_entry(fl, &flctx->flc_posix, fl_list) {
237			if (fl->fl_lmops == &nlmsvc_lock_operations) {
238				spin_unlock(&flctx->flc_lock);
239				return 1;
240			}
241		}
242		spin_unlock(&flctx->flc_lock);
243	}
244	file->f_locks = 0;
245	return 0;
246}
247
248/*
249 * Loop over all files in the file table.
250 */
251static int
252nlm_traverse_files(void *data, nlm_host_match_fn_t match,
253		int (*is_failover_file)(void *data, struct nlm_file *file))
254{
255	struct hlist_node *next;
256	struct nlm_file	*file;
257	int i, ret = 0;
258
259	mutex_lock(&nlm_file_mutex);
260	for (i = 0; i < FILE_NRHASH; i++) {
261		hlist_for_each_entry_safe(file, next, &nlm_files[i], f_list) {
262			if (is_failover_file && !is_failover_file(data, file))
263				continue;
264			file->f_count++;
265			mutex_unlock(&nlm_file_mutex);
266
267			/* Traverse locks, blocks and shares of this file
268			 * and update file->f_locks count */
269			if (nlm_inspect_file(data, file, match))
270				ret = 1;
271
272			mutex_lock(&nlm_file_mutex);
273			file->f_count--;
274			/* No more references to this file. Let go of it. */
275			if (list_empty(&file->f_blocks) && !file->f_locks
276			 && !file->f_shares && !file->f_count) {
277				hlist_del(&file->f_list);
278				nlmsvc_ops->fclose(file->f_file);
279				kfree(file);
280			}
281		}
282	}
283	mutex_unlock(&nlm_file_mutex);
284	return ret;
285}
286
287/*
288 * Release file. If there are no more remote locks on this file,
289 * close it and free the handle.
290 *
291 * Note that we can't do proper reference counting without major
292 * contortions because the code in fs/locks.c creates, deletes and
293 * splits locks without notification. Our only way is to walk the
294 * entire lock list each time we remove a lock.
295 */
296void
297nlm_release_file(struct nlm_file *file)
298{
299	dprintk("lockd: nlm_release_file(%p, ct = %d)\n",
300				file, file->f_count);
301
302	/* Lock file table */
303	mutex_lock(&nlm_file_mutex);
304
305	/* If there are no more locks etc, delete the file */
306	if (--file->f_count == 0 && !nlm_file_inuse(file))
307		nlm_delete_file(file);
308
309	mutex_unlock(&nlm_file_mutex);
310}
311
312/*
313 * Helpers function for resource traversal
314 *
315 * nlmsvc_mark_host:
316 *	used by the garbage collector; simply sets h_inuse only for those
317 *	hosts, which passed network check.
318 *	Always returns 0.
319 *
320 * nlmsvc_same_host:
321 *	returns 1 iff the two hosts match. Used to release
322 *	all resources bound to a specific host.
323 *
324 * nlmsvc_is_client:
325 *	returns 1 iff the host is a client.
326 *	Used by nlmsvc_invalidate_all
327 */
328
329static int
330nlmsvc_mark_host(void *data, struct nlm_host *hint)
331{
332	struct nlm_host *host = data;
333
334	if ((hint->net == NULL) ||
335	    (host->net == hint->net))
336		host->h_inuse = 1;
337	return 0;
338}
339
340static int
341nlmsvc_same_host(void *data, struct nlm_host *other)
342{
343	struct nlm_host *host = data;
344
345	return host == other;
346}
347
348static int
349nlmsvc_is_client(void *data, struct nlm_host *dummy)
350{
351	struct nlm_host *host = data;
352
353	if (host->h_server) {
354		/* we are destroying locks even though the client
355		 * hasn't asked us too, so don't unmonitor the
356		 * client
357		 */
358		if (host->h_nsmhandle)
359			host->h_nsmhandle->sm_sticky = 1;
360		return 1;
361	} else
362		return 0;
363}
364
365/*
366 * Mark all hosts that still hold resources
367 */
368void
369nlmsvc_mark_resources(struct net *net)
370{
371	struct nlm_host hint;
372
373	dprintk("lockd: nlmsvc_mark_resources for net %p\n", net);
374	hint.net = net;
375	nlm_traverse_files(&hint, nlmsvc_mark_host, NULL);
376}
377
378/*
379 * Release all resources held by the given client
380 */
381void
382nlmsvc_free_host_resources(struct nlm_host *host)
383{
384	dprintk("lockd: nlmsvc_free_host_resources\n");
385
386	if (nlm_traverse_files(host, nlmsvc_same_host, NULL)) {
387		printk(KERN_WARNING
388			"lockd: couldn't remove all locks held by %s\n",
389			host->h_name);
390		BUG();
391	}
392}
393
394/**
395 * nlmsvc_invalidate_all - remove all locks held for clients
396 *
397 * Release all locks held by NFS clients.
398 *
399 */
400void
401nlmsvc_invalidate_all(void)
402{
403	/*
404	 * Previously, the code would call
405	 * nlmsvc_free_host_resources for each client in
406	 * turn, which is about as inefficient as it gets.
407	 * Now we just do it once in nlm_traverse_files.
408	 */
409	nlm_traverse_files(NULL, nlmsvc_is_client, NULL);
410}
411
412static int
413nlmsvc_match_sb(void *datap, struct nlm_file *file)
414{
415	struct super_block *sb = datap;
416
417	return sb == file_inode(file->f_file)->i_sb;
418}
419
420/**
421 * nlmsvc_unlock_all_by_sb - release locks held on this file system
422 * @sb: super block
423 *
424 * Release all locks held by clients accessing this file system.
425 */
426int
427nlmsvc_unlock_all_by_sb(struct super_block *sb)
428{
429	int ret;
430
431	ret = nlm_traverse_files(sb, nlmsvc_always_match, nlmsvc_match_sb);
432	return ret ? -EIO : 0;
433}
434EXPORT_SYMBOL_GPL(nlmsvc_unlock_all_by_sb);
435
436static int
437nlmsvc_match_ip(void *datap, struct nlm_host *host)
438{
439	return rpc_cmp_addr(nlm_srcaddr(host), datap);
440}
441
442/**
443 * nlmsvc_unlock_all_by_ip - release local locks by IP address
444 * @server_addr: server's IP address as seen by clients
445 *
446 * Release all locks held by clients accessing this host
447 * via the passed in IP address.
448 */
449int
450nlmsvc_unlock_all_by_ip(struct sockaddr *server_addr)
451{
452	int ret;
453
454	ret = nlm_traverse_files(server_addr, nlmsvc_match_ip, NULL);
455	return ret ? -EIO : 0;
456}
457EXPORT_SYMBOL_GPL(nlmsvc_unlock_all_by_ip);
v5.9
  1// SPDX-License-Identifier: GPL-2.0-only
  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
 10#include <linux/types.h>
 11#include <linux/string.h>
 12#include <linux/time.h>
 13#include <linux/in.h>
 14#include <linux/slab.h>
 15#include <linux/mutex.h>
 16#include <linux/sunrpc/svc.h>
 17#include <linux/sunrpc/addr.h>
 18#include <linux/lockd/lockd.h>
 19#include <linux/lockd/share.h>
 20#include <linux/module.h>
 21#include <linux/mount.h>
 22#include <uapi/linux/nfs2.h>
 23
 24#define NLMDBG_FACILITY		NLMDBG_SVCSUBS
 25
 26
 27/*
 28 * Global file hash table
 29 */
 30#define FILE_HASH_BITS		7
 31#define FILE_NRHASH		(1<<FILE_HASH_BITS)
 32static struct hlist_head	nlm_files[FILE_NRHASH];
 33static DEFINE_MUTEX(nlm_file_mutex);
 34
 35#ifdef CONFIG_SUNRPC_DEBUG
 36static 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
 46static inline void nlm_debug_print_file(char *msg, struct nlm_file *file)
 47{
 48	struct inode *inode = locks_inode(file->f_file);
 49
 50	dprintk("lockd: %s %s/%ld\n",
 51		msg, inode->i_sb->s_id, inode->i_ino);
 52}
 53#else
 54static inline void nlm_debug_print_fh(char *msg, struct nfs_fh *f)
 55{
 56	return;
 57}
 58
 59static inline void nlm_debug_print_file(char *msg, struct nlm_file *file)
 60{
 61	return;
 62}
 63#endif
 64
 65static 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 */
 83__be32
 84nlm_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;
 89	__be32		nfserr;
 90
 91	nlm_debug_print_fh("nlm_lookup_file", f);
 92
 93	hash = file_hash(f);
 94
 95	/* Lock file table */
 96	mutex_lock(&nlm_file_mutex);
 97
 98	hlist_for_each_entry(file, &nlm_files[hash], f_list)
 99		if (!nfs_compare_fh(&file->f_handle, f))
100			goto found;
101
102	nlm_debug_print_fh("creating file for", f);
103
104	nfserr = nlm_lck_denied_nolocks;
105	file = kzalloc(sizeof(*file), GFP_KERNEL);
106	if (!file)
107		goto out_unlock;
108
109	memcpy(&file->f_handle, f, sizeof(struct nfs_fh));
110	mutex_init(&file->f_mutex);
111	INIT_HLIST_NODE(&file->f_list);
112	INIT_LIST_HEAD(&file->f_blocks);
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) {
121		dprintk("lockd: open failed (error %d)\n", nfserr);
122		goto out_free;
123	}
124
125	hlist_add_head(&file->f_list, &nlm_files[hash]);
126
127found:
128	dprintk("lockd: found file %p (count %d)\n", file, file->f_count);
129	*result = file;
130	file->f_count++;
131	nfserr = 0;
132
133out_unlock:
134	mutex_unlock(&nlm_file_mutex);
135	return nfserr;
136
137out_free:
138	kfree(file);
139	goto out_unlock;
140}
141
142/*
143 * Delete a file after having released all locks, blocks and shares
144 */
145static inline void
146nlm_delete_file(struct nlm_file *file)
147{
148	nlm_debug_print_file("closing file", file);
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");
155	}
156}
157
158/*
159 * Loop over all locks on the given file and perform the specified
160 * action.
161 */
162static int
163nlm_traverse_locks(struct nlm_host *host, struct nlm_file *file,
164			nlm_host_match_fn_t match)
165{
166	struct inode	 *inode = nlmsvc_file_inode(file);
167	struct file_lock *fl;
168	struct file_lock_context *flctx = inode->i_flctx;
169	struct nlm_host	 *lockhost;
170
171	if (!flctx || list_empty_careful(&flctx->flc_posix))
172		return 0;
173again:
174	file->f_locks = 0;
175	spin_lock(&flctx->flc_lock);
176	list_for_each_entry(fl, &flctx->flc_posix, fl_list) {
177		if (fl->fl_lmops != &nlmsvc_lock_operations)
178			continue;
179
180		/* update current lock count */
181		file->f_locks++;
182
183		lockhost = ((struct nlm_lockowner *)fl->fl_owner)->host;
184		if (match(lockhost, host)) {
185			struct file_lock lock = *fl;
186
187			spin_unlock(&flctx->flc_lock);
188			lock.fl_type  = F_UNLCK;
189			lock.fl_start = 0;
190			lock.fl_end   = OFFSET_MAX;
191			if (vfs_lock_file(file->f_file, F_SETLK, &lock, NULL) < 0) {
192				printk("lockd: unlock failure in %s:%d\n",
193						__FILE__, __LINE__);
194				return 1;
195			}
196			goto again;
197		}
198	}
199	spin_unlock(&flctx->flc_lock);
200
201	return 0;
202}
203
204static int
205nlmsvc_always_match(void *dummy1, struct nlm_host *dummy2)
206{
207	return 1;
208}
209
210/*
211 * Inspect a single file
212 */
213static inline int
214nlm_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.
224 */
225static inline int
226nlm_file_inuse(struct nlm_file *file)
227{
228	struct inode	 *inode = nlmsvc_file_inode(file);
229	struct file_lock *fl;
230	struct file_lock_context *flctx = inode->i_flctx;
231
232	if (file->f_count || !list_empty(&file->f_blocks) || file->f_shares)
233		return 1;
234
235	if (flctx && !list_empty_careful(&flctx->flc_posix)) {
236		spin_lock(&flctx->flc_lock);
237		list_for_each_entry(fl, &flctx->flc_posix, fl_list) {
238			if (fl->fl_lmops == &nlmsvc_lock_operations) {
239				spin_unlock(&flctx->flc_lock);
240				return 1;
241			}
242		}
243		spin_unlock(&flctx->flc_lock);
244	}
245	file->f_locks = 0;
246	return 0;
247}
248
249/*
250 * Loop over all files in the file table.
251 */
252static int
253nlm_traverse_files(void *data, nlm_host_match_fn_t match,
254		int (*is_failover_file)(void *data, struct nlm_file *file))
255{
256	struct hlist_node *next;
257	struct nlm_file	*file;
258	int i, ret = 0;
259
260	mutex_lock(&nlm_file_mutex);
261	for (i = 0; i < FILE_NRHASH; i++) {
262		hlist_for_each_entry_safe(file, next, &nlm_files[i], f_list) {
263			if (is_failover_file && !is_failover_file(data, file))
264				continue;
265			file->f_count++;
266			mutex_unlock(&nlm_file_mutex);
267
268			/* Traverse locks, blocks and shares of this file
269			 * and update file->f_locks count */
270			if (nlm_inspect_file(data, file, match))
271				ret = 1;
272
273			mutex_lock(&nlm_file_mutex);
274			file->f_count--;
275			/* No more references to this file. Let go of it. */
276			if (list_empty(&file->f_blocks) && !file->f_locks
277			 && !file->f_shares && !file->f_count) {
278				hlist_del(&file->f_list);
279				nlmsvc_ops->fclose(file->f_file);
280				kfree(file);
281			}
282		}
283	}
284	mutex_unlock(&nlm_file_mutex);
285	return ret;
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 */
297void
298nlm_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 */
304	mutex_lock(&nlm_file_mutex);
305
306	/* If there are no more locks etc, delete the file */
307	if (--file->f_count == 0 && !nlm_file_inuse(file))
308		nlm_delete_file(file);
309
310	mutex_unlock(&nlm_file_mutex);
311}
312
313/*
314 * Helpers function for resource traversal
315 *
316 * nlmsvc_mark_host:
317 *	used by the garbage collector; simply sets h_inuse only for those
318 *	hosts, which passed network check.
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 */
329
330static int
331nlmsvc_mark_host(void *data, struct nlm_host *hint)
332{
333	struct nlm_host *host = data;
334
335	if ((hint->net == NULL) ||
336	    (host->net == hint->net))
337		host->h_inuse = 1;
338	return 0;
339}
340
341static int
342nlmsvc_same_host(void *data, struct nlm_host *other)
343{
344	struct nlm_host *host = data;
345
346	return host == other;
347}
348
349static int
350nlmsvc_is_client(void *data, struct nlm_host *dummy)
351{
352	struct nlm_host *host = data;
353
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;
364}
365
366/*
367 * Mark all hosts that still hold resources
368 */
369void
370nlmsvc_mark_resources(struct net *net)
371{
372	struct nlm_host hint;
373
374	dprintk("lockd: %s for net %x\n", __func__, net ? net->ns.inum : 0);
375	hint.net = net;
376	nlm_traverse_files(&hint, nlmsvc_mark_host, NULL);
377}
378
379/*
380 * Release all resources held by the given client
381 */
382void
383nlmsvc_free_host_resources(struct nlm_host *host)
384{
385	dprintk("lockd: nlmsvc_free_host_resources\n");
386
387	if (nlm_traverse_files(host, nlmsvc_same_host, NULL)) {
388		printk(KERN_WARNING
389			"lockd: couldn't remove all locks held by %s\n",
390			host->h_name);
391		BUG();
392	}
393}
394
395/**
396 * nlmsvc_invalidate_all - remove all locks held for clients
397 *
398 * Release all locks held by NFS clients.
399 *
400 */
401void
402nlmsvc_invalidate_all(void)
403{
404	/*
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	 */
410	nlm_traverse_files(NULL, nlmsvc_is_client, NULL);
411}
412
413static int
414nlmsvc_match_sb(void *datap, struct nlm_file *file)
415{
416	struct super_block *sb = datap;
417
418	return sb == locks_inode(file->f_file)->i_sb;
419}
420
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 */
427int
428nlmsvc_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;
434}
435EXPORT_SYMBOL_GPL(nlmsvc_unlock_all_by_sb);
436
437static int
438nlmsvc_match_ip(void *datap, struct nlm_host *host)
439{
440	return rpc_cmp_addr(nlm_srcaddr(host), datap);
441}
442
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 */
450int
451nlmsvc_unlock_all_by_ip(struct sockaddr *server_addr)
452{
453	int ret;
454
455	ret = nlm_traverse_files(server_addr, nlmsvc_match_ip, NULL);
456	return ret ? -EIO : 0;
457}
458EXPORT_SYMBOL_GPL(nlmsvc_unlock_all_by_ip);