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> |
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; |
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 | |
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, |
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; |
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 | */ |
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; |
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, |
241 | int (*is_failover_file)(void *data, struct nlm_file *file)) | |
1da177e4 | 242 | { |
07ba8063 OK |
243 | struct hlist_node *pos, *next; |
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)) |
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 |
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); |
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); |
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 | |
293 | /* If there are no more locks etc, delete the file */ | |
f2af793d OK |
294 | if (--file->f_count == 0 && !nlm_file_inuse(file)) |
295 | nlm_delete_file(file); | |
1da177e4 | 296 | |
353ab6e9 | 297 | mutex_unlock(&nlm_file_mutex); |
1da177e4 LT |
298 | } |
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; |
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; |
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; |
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 | } |
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(); |
372 | } | |
1da177e4 LT |
373 | } |
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 | { | |
781b61a6 | 420 | return nlm_cmp_addr(nlm_srcaddr(host), datap); |
4373ea84 WC |
421 | } |
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 | { |
433 | int ret; | |
4373ea84 | 434 | |
367c8c7b CL |
435 | ret = nlm_traverse_files(server_addr, nlmsvc_match_ip, NULL); |
436 | return ret ? -EIO : 0; | |
4373ea84 WC |
437 | } |
438 | EXPORT_SYMBOL_GPL(nlmsvc_unlock_all_by_ip); |