Commit | Line | Data |
---|---|---|
1da177e4 LT |
1 | /* -*- c -*- --------------------------------------------------------------- * |
2 | * | |
3 | * linux/fs/autofs/inode.c | |
4 | * | |
5 | * Copyright 1997-1998 Transmeta Corporation -- All Rights Reserved | |
34ca959c | 6 | * Copyright 2005-2006 Ian Kent <raven@themaw.net> |
1da177e4 LT |
7 | * |
8 | * This file is part of the Linux kernel and is made available under | |
9 | * the terms of the GNU General Public License, version 2, or at your | |
10 | * option, any later version, incorporated herein by reference. | |
11 | * | |
12 | * ------------------------------------------------------------------------- */ | |
13 | ||
14 | #include <linux/kernel.h> | |
15 | #include <linux/slab.h> | |
16 | #include <linux/file.h> | |
d7c4a5f1 | 17 | #include <linux/seq_file.h> |
1da177e4 LT |
18 | #include <linux/pagemap.h> |
19 | #include <linux/parser.h> | |
20 | #include <linux/bitops.h> | |
104e49fc | 21 | #include <linux/smp_lock.h> |
e18fa700 | 22 | #include <linux/magic.h> |
1da177e4 LT |
23 | #include "autofs_i.h" |
24 | #include <linux/module.h> | |
25 | ||
26 | static void ino_lnkfree(struct autofs_info *ino) | |
27 | { | |
f99d49ad JJ |
28 | kfree(ino->u.symlink); |
29 | ino->u.symlink = NULL; | |
1da177e4 LT |
30 | } |
31 | ||
32 | struct autofs_info *autofs4_init_ino(struct autofs_info *ino, | |
33 | struct autofs_sb_info *sbi, mode_t mode) | |
34 | { | |
35 | int reinit = 1; | |
36 | ||
37 | if (ino == NULL) { | |
38 | reinit = 0; | |
39 | ino = kmalloc(sizeof(*ino), GFP_KERNEL); | |
40 | } | |
41 | ||
42 | if (ino == NULL) | |
43 | return NULL; | |
44 | ||
45 | ino->flags = 0; | |
46 | ino->mode = mode; | |
47 | ino->inode = NULL; | |
48 | ino->dentry = NULL; | |
49 | ino->size = 0; | |
50 | ||
51 | ino->last_used = jiffies; | |
1aff3c8b | 52 | atomic_set(&ino->count, 0); |
1da177e4 LT |
53 | |
54 | ino->sbi = sbi; | |
55 | ||
56 | if (reinit && ino->free) | |
57 | (ino->free)(ino); | |
58 | ||
59 | memset(&ino->u, 0, sizeof(ino->u)); | |
60 | ||
61 | ino->free = NULL; | |
62 | ||
63 | if (S_ISLNK(mode)) | |
64 | ino->free = ino_lnkfree; | |
65 | ||
66 | return ino; | |
67 | } | |
68 | ||
69 | void autofs4_free_ino(struct autofs_info *ino) | |
70 | { | |
1aff3c8b IK |
71 | struct autofs_info *p_ino; |
72 | ||
1da177e4 LT |
73 | if (ino->dentry) { |
74 | ino->dentry->d_fsdata = NULL; | |
1aff3c8b IK |
75 | if (ino->dentry->d_inode) { |
76 | struct dentry *parent = ino->dentry->d_parent; | |
77 | if (atomic_dec_and_test(&ino->count)) { | |
78 | p_ino = autofs4_dentry_ino(parent); | |
79 | if (p_ino && parent != ino->dentry) | |
80 | atomic_dec(&p_ino->count); | |
81 | } | |
1da177e4 | 82 | dput(ino->dentry); |
1aff3c8b | 83 | } |
1da177e4 LT |
84 | ino->dentry = NULL; |
85 | } | |
86 | if (ino->free) | |
87 | (ino->free)(ino); | |
88 | kfree(ino); | |
89 | } | |
90 | ||
104e49fc IK |
91 | /* |
92 | * Deal with the infamous "Busy inodes after umount ..." message. | |
93 | * | |
94 | * Clean up the dentry tree. This happens with autofs if the user | |
95 | * space program goes away due to a SIGKILL, SIGSEGV etc. | |
96 | */ | |
97 | static void autofs4_force_release(struct autofs_sb_info *sbi) | |
98 | { | |
6ce31523 | 99 | struct dentry *this_parent = sbi->sb->s_root; |
104e49fc IK |
100 | struct list_head *next; |
101 | ||
102 | spin_lock(&dcache_lock); | |
103 | repeat: | |
104 | next = this_parent->d_subdirs.next; | |
105 | resume: | |
106 | while (next != &this_parent->d_subdirs) { | |
5160ee6f | 107 | struct dentry *dentry = list_entry(next, struct dentry, d_u.d_child); |
104e49fc IK |
108 | |
109 | /* Negative dentry - don`t care */ | |
110 | if (!simple_positive(dentry)) { | |
111 | next = next->next; | |
112 | continue; | |
113 | } | |
114 | ||
115 | if (!list_empty(&dentry->d_subdirs)) { | |
116 | this_parent = dentry; | |
117 | goto repeat; | |
118 | } | |
119 | ||
120 | next = next->next; | |
121 | spin_unlock(&dcache_lock); | |
122 | ||
123 | DPRINTK("dentry %p %.*s", | |
124 | dentry, (int)dentry->d_name.len, dentry->d_name.name); | |
125 | ||
126 | dput(dentry); | |
127 | spin_lock(&dcache_lock); | |
128 | } | |
129 | ||
6ce31523 | 130 | if (this_parent != sbi->sb->s_root) { |
104e49fc IK |
131 | struct dentry *dentry = this_parent; |
132 | ||
5160ee6f | 133 | next = this_parent->d_u.d_child.next; |
104e49fc IK |
134 | this_parent = this_parent->d_parent; |
135 | spin_unlock(&dcache_lock); | |
136 | DPRINTK("parent dentry %p %.*s", | |
137 | dentry, (int)dentry->d_name.len, dentry->d_name.name); | |
138 | dput(dentry); | |
139 | spin_lock(&dcache_lock); | |
140 | goto resume; | |
141 | } | |
142 | spin_unlock(&dcache_lock); | |
104e49fc IK |
143 | } |
144 | ||
6ce31523 | 145 | void autofs4_kill_sb(struct super_block *sb) |
1da177e4 LT |
146 | { |
147 | struct autofs_sb_info *sbi = autofs4_sbi(sb); | |
148 | ||
149 | sb->s_fs_info = NULL; | |
150 | ||
151 | if ( !sbi->catatonic ) | |
152 | autofs4_catatonic_mode(sbi); /* Free wait queues, close pipe */ | |
153 | ||
104e49fc | 154 | /* Clean up and release dangling references */ |
3370c74b | 155 | autofs4_force_release(sbi); |
104e49fc | 156 | |
1da177e4 LT |
157 | kfree(sbi); |
158 | ||
159 | DPRINTK("shutting down"); | |
6ce31523 | 160 | kill_anon_super(sb); |
1da177e4 LT |
161 | } |
162 | ||
d7c4a5f1 IK |
163 | static int autofs4_show_options(struct seq_file *m, struct vfsmount *mnt) |
164 | { | |
165 | struct autofs_sb_info *sbi = autofs4_sbi(mnt->mnt_sb); | |
166 | ||
167 | if (!sbi) | |
168 | return 0; | |
169 | ||
170 | seq_printf(m, ",fd=%d", sbi->pipefd); | |
171 | seq_printf(m, ",pgrp=%d", sbi->oz_pgrp); | |
172 | seq_printf(m, ",timeout=%lu", sbi->exp_timeout/HZ); | |
173 | seq_printf(m, ",minproto=%d", sbi->min_proto); | |
174 | seq_printf(m, ",maxproto=%d", sbi->max_proto); | |
175 | ||
44d53eb0 | 176 | if (sbi->type & AUTOFS_TYPE_OFFSET) |
34ca959c | 177 | seq_printf(m, ",offset"); |
44d53eb0 | 178 | else if (sbi->type & AUTOFS_TYPE_DIRECT) |
34ca959c IK |
179 | seq_printf(m, ",direct"); |
180 | else | |
181 | seq_printf(m, ",indirect"); | |
182 | ||
d7c4a5f1 IK |
183 | return 0; |
184 | } | |
185 | ||
1da177e4 | 186 | static struct super_operations autofs4_sops = { |
1da177e4 | 187 | .statfs = simple_statfs, |
d7c4a5f1 | 188 | .show_options = autofs4_show_options, |
1da177e4 LT |
189 | }; |
190 | ||
34ca959c IK |
191 | enum {Opt_err, Opt_fd, Opt_uid, Opt_gid, Opt_pgrp, Opt_minproto, Opt_maxproto, |
192 | Opt_indirect, Opt_direct, Opt_offset}; | |
1da177e4 LT |
193 | |
194 | static match_table_t tokens = { | |
195 | {Opt_fd, "fd=%u"}, | |
196 | {Opt_uid, "uid=%u"}, | |
197 | {Opt_gid, "gid=%u"}, | |
198 | {Opt_pgrp, "pgrp=%u"}, | |
199 | {Opt_minproto, "minproto=%u"}, | |
200 | {Opt_maxproto, "maxproto=%u"}, | |
34ca959c IK |
201 | {Opt_indirect, "indirect"}, |
202 | {Opt_direct, "direct"}, | |
203 | {Opt_offset, "offset"}, | |
1da177e4 LT |
204 | {Opt_err, NULL} |
205 | }; | |
206 | ||
207 | static int parse_options(char *options, int *pipefd, uid_t *uid, gid_t *gid, | |
34ca959c IK |
208 | pid_t *pgrp, unsigned int *type, |
209 | int *minproto, int *maxproto) | |
1da177e4 LT |
210 | { |
211 | char *p; | |
212 | substring_t args[MAX_OPT_ARGS]; | |
213 | int option; | |
214 | ||
215 | *uid = current->uid; | |
216 | *gid = current->gid; | |
217 | *pgrp = process_group(current); | |
218 | ||
219 | *minproto = AUTOFS_MIN_PROTO_VERSION; | |
220 | *maxproto = AUTOFS_MAX_PROTO_VERSION; | |
221 | ||
222 | *pipefd = -1; | |
223 | ||
224 | if (!options) | |
225 | return 1; | |
226 | ||
227 | while ((p = strsep(&options, ",")) != NULL) { | |
228 | int token; | |
229 | if (!*p) | |
230 | continue; | |
231 | ||
232 | token = match_token(p, tokens, args); | |
233 | switch (token) { | |
234 | case Opt_fd: | |
235 | if (match_int(args, pipefd)) | |
236 | return 1; | |
237 | break; | |
238 | case Opt_uid: | |
239 | if (match_int(args, &option)) | |
240 | return 1; | |
241 | *uid = option; | |
242 | break; | |
243 | case Opt_gid: | |
244 | if (match_int(args, &option)) | |
245 | return 1; | |
246 | *gid = option; | |
247 | break; | |
248 | case Opt_pgrp: | |
249 | if (match_int(args, &option)) | |
250 | return 1; | |
251 | *pgrp = option; | |
252 | break; | |
253 | case Opt_minproto: | |
254 | if (match_int(args, &option)) | |
255 | return 1; | |
256 | *minproto = option; | |
257 | break; | |
258 | case Opt_maxproto: | |
259 | if (match_int(args, &option)) | |
260 | return 1; | |
261 | *maxproto = option; | |
262 | break; | |
34ca959c | 263 | case Opt_indirect: |
44d53eb0 | 264 | *type = AUTOFS_TYPE_INDIRECT; |
34ca959c IK |
265 | break; |
266 | case Opt_direct: | |
44d53eb0 | 267 | *type = AUTOFS_TYPE_DIRECT; |
34ca959c IK |
268 | break; |
269 | case Opt_offset: | |
44d53eb0 | 270 | *type = AUTOFS_TYPE_DIRECT | AUTOFS_TYPE_OFFSET; |
34ca959c | 271 | break; |
1da177e4 LT |
272 | default: |
273 | return 1; | |
274 | } | |
275 | } | |
276 | return (*pipefd < 0); | |
277 | } | |
278 | ||
279 | static struct autofs_info *autofs4_mkroot(struct autofs_sb_info *sbi) | |
280 | { | |
281 | struct autofs_info *ino; | |
282 | ||
283 | ino = autofs4_init_ino(NULL, sbi, S_IFDIR | 0755); | |
284 | if (!ino) | |
285 | return NULL; | |
286 | ||
287 | return ino; | |
288 | } | |
289 | ||
34ca959c IK |
290 | static struct dentry_operations autofs4_sb_dentry_operations = { |
291 | .d_release = autofs4_dentry_release, | |
292 | }; | |
293 | ||
1da177e4 LT |
294 | int autofs4_fill_super(struct super_block *s, void *data, int silent) |
295 | { | |
296 | struct inode * root_inode; | |
297 | struct dentry * root; | |
298 | struct file * pipe; | |
299 | int pipefd; | |
300 | struct autofs_sb_info *sbi; | |
301 | struct autofs_info *ino; | |
1da177e4 LT |
302 | |
303 | sbi = (struct autofs_sb_info *) kmalloc(sizeof(*sbi), GFP_KERNEL); | |
304 | if ( !sbi ) | |
305 | goto fail_unlock; | |
306 | DPRINTK("starting up, sbi = %p",sbi); | |
307 | ||
308 | memset(sbi, 0, sizeof(*sbi)); | |
309 | ||
310 | s->s_fs_info = sbi; | |
311 | sbi->magic = AUTOFS_SBI_MAGIC; | |
d7c4a5f1 | 312 | sbi->pipefd = -1; |
1da177e4 LT |
313 | sbi->catatonic = 0; |
314 | sbi->exp_timeout = 0; | |
315 | sbi->oz_pgrp = process_group(current); | |
316 | sbi->sb = s; | |
317 | sbi->version = 0; | |
318 | sbi->sub_version = 0; | |
34ca959c | 319 | sbi->type = 0; |
d7c4a5f1 IK |
320 | sbi->min_proto = 0; |
321 | sbi->max_proto = 0; | |
1d5599e3 | 322 | mutex_init(&sbi->wq_mutex); |
3a9720ce | 323 | spin_lock_init(&sbi->fs_lock); |
1da177e4 LT |
324 | sbi->queues = NULL; |
325 | s->s_blocksize = 1024; | |
326 | s->s_blocksize_bits = 10; | |
327 | s->s_magic = AUTOFS_SUPER_MAGIC; | |
328 | s->s_op = &autofs4_sops; | |
329 | s->s_time_gran = 1; | |
330 | ||
331 | /* | |
332 | * Get the root inode and dentry, but defer checking for errors. | |
333 | */ | |
334 | ino = autofs4_mkroot(sbi); | |
335 | if (!ino) | |
336 | goto fail_free; | |
337 | root_inode = autofs4_get_inode(s, ino); | |
1da177e4 | 338 | if (!root_inode) |
34ca959c | 339 | goto fail_ino; |
1da177e4 | 340 | |
1da177e4 | 341 | root = d_alloc_root(root_inode); |
1da177e4 LT |
342 | if (!root) |
343 | goto fail_iput; | |
34ca959c IK |
344 | pipe = NULL; |
345 | ||
346 | root->d_op = &autofs4_sb_dentry_operations; | |
347 | root->d_fsdata = ino; | |
1da177e4 LT |
348 | |
349 | /* Can this call block? */ | |
350 | if (parse_options(data, &pipefd, | |
351 | &root_inode->i_uid, &root_inode->i_gid, | |
34ca959c | 352 | &sbi->oz_pgrp, &sbi->type, |
d7c4a5f1 | 353 | &sbi->min_proto, &sbi->max_proto)) { |
1da177e4 LT |
354 | printk("autofs: called with bogus options\n"); |
355 | goto fail_dput; | |
356 | } | |
357 | ||
34ca959c | 358 | root_inode->i_fop = &autofs4_root_operations; |
44d53eb0 | 359 | root_inode->i_op = sbi->type & AUTOFS_TYPE_DIRECT ? |
34ca959c IK |
360 | &autofs4_direct_root_inode_operations : |
361 | &autofs4_indirect_root_inode_operations; | |
362 | ||
1da177e4 | 363 | /* Couldn't this be tested earlier? */ |
d7c4a5f1 IK |
364 | if (sbi->max_proto < AUTOFS_MIN_PROTO_VERSION || |
365 | sbi->min_proto > AUTOFS_MAX_PROTO_VERSION) { | |
1da177e4 LT |
366 | printk("autofs: kernel does not match daemon version " |
367 | "daemon (%d, %d) kernel (%d, %d)\n", | |
d7c4a5f1 | 368 | sbi->min_proto, sbi->max_proto, |
1da177e4 LT |
369 | AUTOFS_MIN_PROTO_VERSION, AUTOFS_MAX_PROTO_VERSION); |
370 | goto fail_dput; | |
371 | } | |
372 | ||
d7c4a5f1 IK |
373 | /* Establish highest kernel protocol version */ |
374 | if (sbi->max_proto > AUTOFS_MAX_PROTO_VERSION) | |
375 | sbi->version = AUTOFS_MAX_PROTO_VERSION; | |
376 | else | |
377 | sbi->version = sbi->max_proto; | |
1da177e4 LT |
378 | sbi->sub_version = AUTOFS_PROTO_SUBVERSION; |
379 | ||
380 | DPRINTK("pipe fd = %d, pgrp = %u", pipefd, sbi->oz_pgrp); | |
381 | pipe = fget(pipefd); | |
382 | ||
383 | if ( !pipe ) { | |
384 | printk("autofs: could not open pipe file descriptor\n"); | |
385 | goto fail_dput; | |
386 | } | |
387 | if ( !pipe->f_op || !pipe->f_op->write ) | |
388 | goto fail_fput; | |
389 | sbi->pipe = pipe; | |
d7c4a5f1 | 390 | sbi->pipefd = pipefd; |
1da177e4 LT |
391 | |
392 | /* | |
393 | * Success! Install the root dentry now to indicate completion. | |
394 | */ | |
395 | s->s_root = root; | |
396 | return 0; | |
397 | ||
398 | /* | |
399 | * Failure ... clean up. | |
400 | */ | |
401 | fail_fput: | |
402 | printk("autofs: pipe file descriptor does not contain proper ops\n"); | |
403 | fput(pipe); | |
404 | /* fall through */ | |
405 | fail_dput: | |
406 | dput(root); | |
407 | goto fail_free; | |
408 | fail_iput: | |
409 | printk("autofs: get root dentry failed\n"); | |
410 | iput(root_inode); | |
34ca959c IK |
411 | fail_ino: |
412 | kfree(ino); | |
1da177e4 LT |
413 | fail_free: |
414 | kfree(sbi); | |
415 | fail_unlock: | |
416 | return -EINVAL; | |
417 | } | |
418 | ||
419 | struct inode *autofs4_get_inode(struct super_block *sb, | |
420 | struct autofs_info *inf) | |
421 | { | |
422 | struct inode *inode = new_inode(sb); | |
423 | ||
424 | if (inode == NULL) | |
425 | return NULL; | |
426 | ||
427 | inf->inode = inode; | |
428 | inode->i_mode = inf->mode; | |
429 | if (sb->s_root) { | |
430 | inode->i_uid = sb->s_root->d_inode->i_uid; | |
431 | inode->i_gid = sb->s_root->d_inode->i_gid; | |
432 | } else { | |
433 | inode->i_uid = 0; | |
434 | inode->i_gid = 0; | |
435 | } | |
1da177e4 LT |
436 | inode->i_blocks = 0; |
437 | inode->i_atime = inode->i_mtime = inode->i_ctime = CURRENT_TIME; | |
438 | ||
439 | if (S_ISDIR(inf->mode)) { | |
440 | inode->i_nlink = 2; | |
441 | inode->i_op = &autofs4_dir_inode_operations; | |
442 | inode->i_fop = &autofs4_dir_operations; | |
443 | } else if (S_ISLNK(inf->mode)) { | |
444 | inode->i_size = inf->size; | |
445 | inode->i_op = &autofs4_symlink_inode_operations; | |
446 | } | |
447 | ||
448 | return inode; | |
449 | } |