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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 LT |
15 | #include <linux/sunrpc/svc.h> |
16 | #include <linux/sunrpc/clnt.h> | |
17 | #include <linux/nfsd/nfsfh.h> | |
18 | #include <linux/nfsd/export.h> | |
19 | #include <linux/lockd/lockd.h> | |
20 | #include <linux/lockd/share.h> | |
4373ea84 WC |
21 | #include <linux/module.h> |
22 | #include <linux/mount.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 | |
0bbacc40 CL |
35 | #ifdef NFSD_DEBUG |
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 | { | |
225a719f | 48 | struct inode *inode = file->f_file->f_path.dentry->d_inode; |
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 | { | |
07ba8063 | 87 | struct hlist_node *pos; |
1da177e4 LT |
88 | struct nlm_file *file; |
89 | unsigned int hash; | |
52921e02 | 90 | __be32 nfserr; |
1da177e4 | 91 | |
50431d94 | 92 | nlm_debug_print_fh("nlm_lookup_file", f); |
1da177e4 LT |
93 | |
94 | hash = file_hash(f); | |
95 | ||
96 | /* Lock file table */ | |
353ab6e9 | 97 | mutex_lock(&nlm_file_mutex); |
1da177e4 | 98 | |
07ba8063 | 99 | hlist_for_each_entry(file, pos, &nlm_files[hash], f_list) |
1da177e4 LT |
100 | if (!nfs_compare_fh(&file->f_handle, f)) |
101 | goto found; | |
102 | ||
0bbacc40 | 103 | nlm_debug_print_fh("creating file for", f); |
1da177e4 LT |
104 | |
105 | nfserr = nlm_lck_denied_nolocks; | |
f8314dc6 | 106 | file = kzalloc(sizeof(*file), GFP_KERNEL); |
1da177e4 LT |
107 | if (!file) |
108 | goto out_unlock; | |
109 | ||
1da177e4 | 110 | memcpy(&file->f_handle, f, sizeof(struct nfs_fh)); |
89e63ef6 | 111 | mutex_init(&file->f_mutex); |
07ba8063 | 112 | INIT_HLIST_NODE(&file->f_list); |
68a2d76c | 113 | INIT_LIST_HEAD(&file->f_blocks); |
1da177e4 LT |
114 | |
115 | /* Open the file. Note that this must not sleep for too long, else | |
116 | * we would lock up lockd:-) So no NFS re-exports, folks. | |
117 | * | |
118 | * We have to make sure we have the right credential to open | |
119 | * the file. | |
120 | */ | |
121 | if ((nfserr = nlmsvc_ops->fopen(rqstp, f, &file->f_file)) != 0) { | |
f0737a39 | 122 | dprintk("lockd: open failed (error %d)\n", nfserr); |
1da177e4 LT |
123 | goto out_free; |
124 | } | |
125 | ||
07ba8063 | 126 | hlist_add_head(&file->f_list, &nlm_files[hash]); |
1da177e4 LT |
127 | |
128 | found: | |
129 | dprintk("lockd: found file %p (count %d)\n", file, file->f_count); | |
130 | *result = file; | |
131 | file->f_count++; | |
132 | nfserr = 0; | |
133 | ||
134 | out_unlock: | |
353ab6e9 | 135 | mutex_unlock(&nlm_file_mutex); |
1da177e4 LT |
136 | return nfserr; |
137 | ||
138 | out_free: | |
139 | kfree(file); | |
1da177e4 LT |
140 | goto out_unlock; |
141 | } | |
142 | ||
143 | /* | |
144 | * Delete a file after having released all locks, blocks and shares | |
145 | */ | |
146 | static inline void | |
147 | nlm_delete_file(struct nlm_file *file) | |
148 | { | |
0bbacc40 | 149 | nlm_debug_print_file("closing file", file); |
07ba8063 OK |
150 | if (!hlist_unhashed(&file->f_list)) { |
151 | hlist_del(&file->f_list); | |
152 | nlmsvc_ops->fclose(file->f_file); | |
153 | kfree(file); | |
154 | } else { | |
155 | printk(KERN_WARNING "lockd: attempt to release unknown file!\n"); | |
1da177e4 | 156 | } |
1da177e4 LT |
157 | } |
158 | ||
159 | /* | |
160 | * Loop over all locks on the given file and perform the specified | |
161 | * action. | |
162 | */ | |
163 | static int | |
f2af793d OK |
164 | nlm_traverse_locks(struct nlm_host *host, struct nlm_file *file, |
165 | nlm_host_match_fn_t match) | |
1da177e4 LT |
166 | { |
167 | struct inode *inode = nlmsvc_file_inode(file); | |
168 | struct file_lock *fl; | |
169 | struct nlm_host *lockhost; | |
170 | ||
171 | again: | |
172 | file->f_locks = 0; | |
763641d8 | 173 | lock_flocks(); /* protects i_flock list */ |
1da177e4 | 174 | for (fl = inode->i_flock; fl; fl = fl->fl_next) { |
7117bf3d | 175 | if (fl->fl_lmops != &nlmsvc_lock_operations) |
1da177e4 LT |
176 | continue; |
177 | ||
178 | /* update current lock count */ | |
179 | file->f_locks++; | |
f2af793d | 180 | |
1da177e4 | 181 | lockhost = (struct nlm_host *) fl->fl_owner; |
f2af793d | 182 | if (match(lockhost, host)) { |
1da177e4 LT |
183 | struct file_lock lock = *fl; |
184 | ||
763641d8 | 185 | unlock_flocks(); |
1da177e4 LT |
186 | lock.fl_type = F_UNLCK; |
187 | lock.fl_start = 0; | |
188 | lock.fl_end = OFFSET_MAX; | |
1a8322b2 | 189 | if (vfs_lock_file(file->f_file, F_SETLK, &lock, NULL) < 0) { |
1da177e4 LT |
190 | printk("lockd: unlock failure in %s:%d\n", |
191 | __FILE__, __LINE__); | |
192 | return 1; | |
193 | } | |
194 | goto again; | |
195 | } | |
196 | } | |
763641d8 | 197 | unlock_flocks(); |
1da177e4 LT |
198 | |
199 | return 0; | |
200 | } | |
201 | ||
17efa372 WC |
202 | static int |
203 | nlmsvc_always_match(void *dummy1, struct nlm_host *dummy2) | |
204 | { | |
205 | return 1; | |
206 | } | |
207 | ||
1da177e4 | 208 | /* |
f2af793d OK |
209 | * Inspect a single file |
210 | */ | |
211 | static inline int | |
212 | nlm_inspect_file(struct nlm_host *host, struct nlm_file *file, nlm_host_match_fn_t match) | |
213 | { | |
214 | nlmsvc_traverse_blocks(host, file, match); | |
215 | nlmsvc_traverse_shares(host, file, match); | |
216 | return nlm_traverse_locks(host, file, match); | |
217 | } | |
218 | ||
219 | /* | |
220 | * Quick check whether there are still any locks, blocks or | |
221 | * shares on a given file. | |
1da177e4 LT |
222 | */ |
223 | static inline int | |
f2af793d | 224 | nlm_file_inuse(struct nlm_file *file) |
1da177e4 | 225 | { |
f2af793d OK |
226 | struct inode *inode = nlmsvc_file_inode(file); |
227 | struct file_lock *fl; | |
228 | ||
229 | if (file->f_count || !list_empty(&file->f_blocks) || file->f_shares) | |
230 | return 1; | |
231 | ||
763641d8 | 232 | lock_flocks(); |
f2af793d | 233 | for (fl = inode->i_flock; fl; fl = fl->fl_next) { |
763641d8 AB |
234 | if (fl->fl_lmops == &nlmsvc_lock_operations) { |
235 | unlock_flocks(); | |
1da177e4 | 236 | return 1; |
763641d8 | 237 | } |
1da177e4 | 238 | } |
763641d8 | 239 | unlock_flocks(); |
f2af793d OK |
240 | file->f_locks = 0; |
241 | return 0; | |
1da177e4 LT |
242 | } |
243 | ||
244 | /* | |
245 | * Loop over all files in the file table. | |
246 | */ | |
247 | static int | |
17efa372 WC |
248 | nlm_traverse_files(void *data, nlm_host_match_fn_t match, |
249 | int (*is_failover_file)(void *data, struct nlm_file *file)) | |
1da177e4 | 250 | { |
07ba8063 OK |
251 | struct hlist_node *pos, *next; |
252 | struct nlm_file *file; | |
01df9c5e | 253 | int i, ret = 0; |
1da177e4 | 254 | |
353ab6e9 | 255 | mutex_lock(&nlm_file_mutex); |
1da177e4 | 256 | for (i = 0; i < FILE_NRHASH; i++) { |
07ba8063 | 257 | hlist_for_each_entry_safe(file, pos, next, &nlm_files[i], f_list) { |
17efa372 WC |
258 | if (is_failover_file && !is_failover_file(data, file)) |
259 | continue; | |
01df9c5e TM |
260 | file->f_count++; |
261 | mutex_unlock(&nlm_file_mutex); | |
262 | ||
1da177e4 LT |
263 | /* Traverse locks, blocks and shares of this file |
264 | * and update file->f_locks count */ | |
4373ea84 | 265 | if (nlm_inspect_file(data, file, match)) |
01df9c5e | 266 | ret = 1; |
1da177e4 | 267 | |
01df9c5e TM |
268 | mutex_lock(&nlm_file_mutex); |
269 | file->f_count--; | |
1da177e4 | 270 | /* No more references to this file. Let go of it. */ |
68a2d76c | 271 | if (list_empty(&file->f_blocks) && !file->f_locks |
1da177e4 | 272 | && !file->f_shares && !file->f_count) { |
07ba8063 | 273 | hlist_del(&file->f_list); |
1da177e4 LT |
274 | nlmsvc_ops->fclose(file->f_file); |
275 | kfree(file); | |
1da177e4 LT |
276 | } |
277 | } | |
278 | } | |
353ab6e9 | 279 | mutex_unlock(&nlm_file_mutex); |
01df9c5e | 280 | return ret; |
1da177e4 LT |
281 | } |
282 | ||
283 | /* | |
284 | * Release file. If there are no more remote locks on this file, | |
285 | * close it and free the handle. | |
286 | * | |
287 | * Note that we can't do proper reference counting without major | |
288 | * contortions because the code in fs/locks.c creates, deletes and | |
289 | * splits locks without notification. Our only way is to walk the | |
290 | * entire lock list each time we remove a lock. | |
291 | */ | |
292 | void | |
293 | nlm_release_file(struct nlm_file *file) | |
294 | { | |
295 | dprintk("lockd: nlm_release_file(%p, ct = %d)\n", | |
296 | file, file->f_count); | |
297 | ||
298 | /* Lock file table */ | |
353ab6e9 | 299 | mutex_lock(&nlm_file_mutex); |
1da177e4 LT |
300 | |
301 | /* If there are no more locks etc, delete the file */ | |
f2af793d OK |
302 | if (--file->f_count == 0 && !nlm_file_inuse(file)) |
303 | nlm_delete_file(file); | |
1da177e4 | 304 | |
353ab6e9 | 305 | mutex_unlock(&nlm_file_mutex); |
1da177e4 LT |
306 | } |
307 | ||
f2af793d OK |
308 | /* |
309 | * Helpers function for resource traversal | |
310 | * | |
311 | * nlmsvc_mark_host: | |
312 | * used by the garbage collector; simply sets h_inuse. | |
313 | * Always returns 0. | |
314 | * | |
315 | * nlmsvc_same_host: | |
316 | * returns 1 iff the two hosts match. Used to release | |
317 | * all resources bound to a specific host. | |
318 | * | |
319 | * nlmsvc_is_client: | |
320 | * returns 1 iff the host is a client. | |
321 | * Used by nlmsvc_invalidate_all | |
322 | */ | |
323 | static int | |
4373ea84 | 324 | nlmsvc_mark_host(void *data, struct nlm_host *dummy) |
f2af793d | 325 | { |
4373ea84 WC |
326 | struct nlm_host *host = data; |
327 | ||
f2af793d OK |
328 | host->h_inuse = 1; |
329 | return 0; | |
330 | } | |
331 | ||
332 | static int | |
4373ea84 | 333 | nlmsvc_same_host(void *data, struct nlm_host *other) |
f2af793d | 334 | { |
4373ea84 WC |
335 | struct nlm_host *host = data; |
336 | ||
f2af793d OK |
337 | return host == other; |
338 | } | |
339 | ||
340 | static int | |
4373ea84 | 341 | nlmsvc_is_client(void *data, struct nlm_host *dummy) |
f2af793d | 342 | { |
4373ea84 WC |
343 | struct nlm_host *host = data; |
344 | ||
4481d103 N |
345 | if (host->h_server) { |
346 | /* we are destroying locks even though the client | |
347 | * hasn't asked us too, so don't unmonitor the | |
348 | * client | |
349 | */ | |
350 | if (host->h_nsmhandle) | |
351 | host->h_nsmhandle->sm_sticky = 1; | |
352 | return 1; | |
353 | } else | |
354 | return 0; | |
f2af793d OK |
355 | } |
356 | ||
1da177e4 LT |
357 | /* |
358 | * Mark all hosts that still hold resources | |
359 | */ | |
360 | void | |
361 | nlmsvc_mark_resources(void) | |
362 | { | |
363 | dprintk("lockd: nlmsvc_mark_resources\n"); | |
17efa372 | 364 | nlm_traverse_files(NULL, nlmsvc_mark_host, NULL); |
1da177e4 LT |
365 | } |
366 | ||
367 | /* | |
368 | * Release all resources held by the given client | |
369 | */ | |
370 | void | |
371 | nlmsvc_free_host_resources(struct nlm_host *host) | |
372 | { | |
373 | dprintk("lockd: nlmsvc_free_host_resources\n"); | |
374 | ||
17efa372 | 375 | if (nlm_traverse_files(host, nlmsvc_same_host, NULL)) { |
1da177e4 | 376 | printk(KERN_WARNING |
f0737a39 | 377 | "lockd: couldn't remove all locks held by %s\n", |
1da177e4 | 378 | host->h_name); |
f0737a39 OK |
379 | BUG(); |
380 | } | |
1da177e4 LT |
381 | } |
382 | ||
367c8c7b CL |
383 | /** |
384 | * nlmsvc_invalidate_all - remove all locks held for clients | |
385 | * | |
386 | * Release all locks held by NFS clients. | |
387 | * | |
1da177e4 LT |
388 | */ |
389 | void | |
390 | nlmsvc_invalidate_all(void) | |
391 | { | |
367c8c7b | 392 | /* |
f2af793d OK |
393 | * Previously, the code would call |
394 | * nlmsvc_free_host_resources for each client in | |
395 | * turn, which is about as inefficient as it gets. | |
396 | * Now we just do it once in nlm_traverse_files. | |
397 | */ | |
17efa372 WC |
398 | nlm_traverse_files(NULL, nlmsvc_is_client, NULL); |
399 | } | |
400 | ||
401 | static int | |
402 | nlmsvc_match_sb(void *datap, struct nlm_file *file) | |
403 | { | |
404 | struct super_block *sb = datap; | |
405 | ||
406 | return sb == file->f_file->f_path.mnt->mnt_sb; | |
407 | } | |
408 | ||
367c8c7b CL |
409 | /** |
410 | * nlmsvc_unlock_all_by_sb - release locks held on this file system | |
411 | * @sb: super block | |
412 | * | |
413 | * Release all locks held by clients accessing this file system. | |
414 | */ | |
17efa372 WC |
415 | int |
416 | nlmsvc_unlock_all_by_sb(struct super_block *sb) | |
417 | { | |
418 | int ret; | |
419 | ||
420 | ret = nlm_traverse_files(sb, nlmsvc_always_match, nlmsvc_match_sb); | |
421 | return ret ? -EIO : 0; | |
1da177e4 | 422 | } |
17efa372 | 423 | EXPORT_SYMBOL_GPL(nlmsvc_unlock_all_by_sb); |
4373ea84 WC |
424 | |
425 | static int | |
426 | nlmsvc_match_ip(void *datap, struct nlm_host *host) | |
427 | { | |
4516fc04 | 428 | return rpc_cmp_addr(nlm_srcaddr(host), datap); |
4373ea84 WC |
429 | } |
430 | ||
367c8c7b CL |
431 | /** |
432 | * nlmsvc_unlock_all_by_ip - release local locks by IP address | |
433 | * @server_addr: server's IP address as seen by clients | |
434 | * | |
435 | * Release all locks held by clients accessing this host | |
436 | * via the passed in IP address. | |
437 | */ | |
4373ea84 | 438 | int |
367c8c7b | 439 | nlmsvc_unlock_all_by_ip(struct sockaddr *server_addr) |
4373ea84 WC |
440 | { |
441 | int ret; | |
4373ea84 | 442 | |
367c8c7b CL |
443 | ret = nlm_traverse_files(server_addr, nlmsvc_match_ip, NULL); |
444 | return ret ? -EIO : 0; | |
4373ea84 WC |
445 | } |
446 | EXPORT_SYMBOL_GPL(nlmsvc_unlock_all_by_ip); |