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14#include <linux/kernel.h>
15#include <linux/slab.h>
16#include <linux/file.h>
17#include <linux/seq_file.h>
18#include <linux/pagemap.h>
19#include <linux/parser.h>
20#include <linux/bitops.h>
21#include <linux/magic.h>
22#include "autofs_i.h"
23#include <linux/module.h>
24
25static void ino_lnkfree(struct autofs_info *ino)
26{
27 kfree(ino->u.symlink);
28 ino->u.symlink = NULL;
29}
30
31struct autofs_info *autofs4_init_ino(struct autofs_info *ino,
32 struct autofs_sb_info *sbi, mode_t mode)
33{
34 int reinit = 1;
35
36 if (ino == NULL) {
37 reinit = 0;
38 ino = kmalloc(sizeof(*ino), GFP_KERNEL);
39 }
40
41 if (ino == NULL)
42 return NULL;
43
44 ino->flags = 0;
45 ino->mode = mode;
46 ino->inode = NULL;
47 ino->dentry = NULL;
48 ino->size = 0;
49
50 INIT_LIST_HEAD(&ino->rehash);
51
52 ino->last_used = jiffies;
53 atomic_set(&ino->count, 0);
54
55 ino->sbi = sbi;
56
57 if (reinit && ino->free)
58 (ino->free)(ino);
59
60 memset(&ino->u, 0, sizeof(ino->u));
61
62 ino->free = NULL;
63
64 if (S_ISLNK(mode))
65 ino->free = ino_lnkfree;
66
67 return ino;
68}
69
70void autofs4_free_ino(struct autofs_info *ino)
71{
72 struct autofs_info *p_ino;
73
74 if (ino->dentry) {
75 ino->dentry->d_fsdata = NULL;
76 if (ino->dentry->d_inode) {
77 struct dentry *parent = ino->dentry->d_parent;
78 if (atomic_dec_and_test(&ino->count)) {
79 p_ino = autofs4_dentry_ino(parent);
80 if (p_ino && parent != ino->dentry)
81 atomic_dec(&p_ino->count);
82 }
83 dput(ino->dentry);
84 }
85 ino->dentry = NULL;
86 }
87 if (ino->free)
88 (ino->free)(ino);
89 kfree(ino);
90}
91
92
93
94
95
96
97
98static void autofs4_force_release(struct autofs_sb_info *sbi)
99{
100 struct dentry *this_parent = sbi->sb->s_root;
101 struct list_head *next;
102
103 if (!sbi->sb->s_root)
104 return;
105
106 spin_lock(&dcache_lock);
107repeat:
108 next = this_parent->d_subdirs.next;
109resume:
110 while (next != &this_parent->d_subdirs) {
111 struct dentry *dentry = list_entry(next, struct dentry, d_u.d_child);
112
113
114 if (!simple_positive(dentry)) {
115 next = next->next;
116 continue;
117 }
118
119 if (!list_empty(&dentry->d_subdirs)) {
120 this_parent = dentry;
121 goto repeat;
122 }
123
124 next = next->next;
125 spin_unlock(&dcache_lock);
126
127 DPRINTK("dentry %p %.*s",
128 dentry, (int)dentry->d_name.len, dentry->d_name.name);
129
130 dput(dentry);
131 spin_lock(&dcache_lock);
132 }
133
134 if (this_parent != sbi->sb->s_root) {
135 struct dentry *dentry = this_parent;
136
137 next = this_parent->d_u.d_child.next;
138 this_parent = this_parent->d_parent;
139 spin_unlock(&dcache_lock);
140 DPRINTK("parent dentry %p %.*s",
141 dentry, (int)dentry->d_name.len, dentry->d_name.name);
142 dput(dentry);
143 spin_lock(&dcache_lock);
144 goto resume;
145 }
146 spin_unlock(&dcache_lock);
147}
148
149void autofs4_kill_sb(struct super_block *sb)
150{
151 struct autofs_sb_info *sbi = autofs4_sbi(sb);
152
153
154
155
156
157
158
159 if (!sbi)
160 goto out_kill_sb;
161
162 if (!sbi->catatonic)
163 autofs4_catatonic_mode(sbi);
164
165
166 autofs4_force_release(sbi);
167
168 sb->s_fs_info = NULL;
169 kfree(sbi);
170
171out_kill_sb:
172 DPRINTK("shutting down");
173 kill_anon_super(sb);
174}
175
176static int autofs4_show_options(struct seq_file *m, struct vfsmount *mnt)
177{
178 struct autofs_sb_info *sbi = autofs4_sbi(mnt->mnt_sb);
179
180 if (!sbi)
181 return 0;
182
183 seq_printf(m, ",fd=%d", sbi->pipefd);
184 seq_printf(m, ",pgrp=%d", sbi->oz_pgrp);
185 seq_printf(m, ",timeout=%lu", sbi->exp_timeout/HZ);
186 seq_printf(m, ",minproto=%d", sbi->min_proto);
187 seq_printf(m, ",maxproto=%d", sbi->max_proto);
188
189 if (sbi->type & AUTOFS_TYPE_OFFSET)
190 seq_printf(m, ",offset");
191 else if (sbi->type & AUTOFS_TYPE_DIRECT)
192 seq_printf(m, ",direct");
193 else
194 seq_printf(m, ",indirect");
195
196 return 0;
197}
198
199static const struct super_operations autofs4_sops = {
200 .statfs = simple_statfs,
201 .show_options = autofs4_show_options,
202};
203
204enum {Opt_err, Opt_fd, Opt_uid, Opt_gid, Opt_pgrp, Opt_minproto, Opt_maxproto,
205 Opt_indirect, Opt_direct, Opt_offset};
206
207static match_table_t tokens = {
208 {Opt_fd, "fd=%u"},
209 {Opt_uid, "uid=%u"},
210 {Opt_gid, "gid=%u"},
211 {Opt_pgrp, "pgrp=%u"},
212 {Opt_minproto, "minproto=%u"},
213 {Opt_maxproto, "maxproto=%u"},
214 {Opt_indirect, "indirect"},
215 {Opt_direct, "direct"},
216 {Opt_offset, "offset"},
217 {Opt_err, NULL}
218};
219
220static int parse_options(char *options, int *pipefd, uid_t *uid, gid_t *gid,
221 pid_t *pgrp, unsigned int *type, int *minproto, int *maxproto)
222{
223 char *p;
224 substring_t args[MAX_OPT_ARGS];
225 int option;
226
227 *uid = current->uid;
228 *gid = current->gid;
229 *pgrp = task_pgrp_nr(current);
230
231 *minproto = AUTOFS_MIN_PROTO_VERSION;
232 *maxproto = AUTOFS_MAX_PROTO_VERSION;
233
234 *pipefd = -1;
235
236 if (!options)
237 return 1;
238
239 while ((p = strsep(&options, ",")) != NULL) {
240 int token;
241 if (!*p)
242 continue;
243
244 token = match_token(p, tokens, args);
245 switch (token) {
246 case Opt_fd:
247 if (match_int(args, pipefd))
248 return 1;
249 break;
250 case Opt_uid:
251 if (match_int(args, &option))
252 return 1;
253 *uid = option;
254 break;
255 case Opt_gid:
256 if (match_int(args, &option))
257 return 1;
258 *gid = option;
259 break;
260 case Opt_pgrp:
261 if (match_int(args, &option))
262 return 1;
263 *pgrp = option;
264 break;
265 case Opt_minproto:
266 if (match_int(args, &option))
267 return 1;
268 *minproto = option;
269 break;
270 case Opt_maxproto:
271 if (match_int(args, &option))
272 return 1;
273 *maxproto = option;
274 break;
275 case Opt_indirect:
276 *type = AUTOFS_TYPE_INDIRECT;
277 break;
278 case Opt_direct:
279 *type = AUTOFS_TYPE_DIRECT;
280 break;
281 case Opt_offset:
282 *type = AUTOFS_TYPE_DIRECT | AUTOFS_TYPE_OFFSET;
283 break;
284 default:
285 return 1;
286 }
287 }
288 return (*pipefd < 0);
289}
290
291static struct autofs_info *autofs4_mkroot(struct autofs_sb_info *sbi)
292{
293 struct autofs_info *ino;
294
295 ino = autofs4_init_ino(NULL, sbi, S_IFDIR | 0755);
296 if (!ino)
297 return NULL;
298
299 return ino;
300}
301
302static struct dentry_operations autofs4_sb_dentry_operations = {
303 .d_release = autofs4_dentry_release,
304};
305
306int autofs4_fill_super(struct super_block *s, void *data, int silent)
307{
308 struct inode * root_inode;
309 struct dentry * root;
310 struct file * pipe;
311 int pipefd;
312 struct autofs_sb_info *sbi;
313 struct autofs_info *ino;
314
315 sbi = kzalloc(sizeof(*sbi), GFP_KERNEL);
316 if (!sbi)
317 goto fail_unlock;
318 DPRINTK("starting up, sbi = %p",sbi);
319
320 s->s_fs_info = sbi;
321 sbi->magic = AUTOFS_SBI_MAGIC;
322 sbi->pipefd = -1;
323 sbi->pipe = NULL;
324 sbi->catatonic = 1;
325 sbi->exp_timeout = 0;
326 sbi->oz_pgrp = task_pgrp_nr(current);
327 sbi->sb = s;
328 sbi->version = 0;
329 sbi->sub_version = 0;
330 sbi->type = 0;
331 sbi->min_proto = 0;
332 sbi->max_proto = 0;
333 mutex_init(&sbi->wq_mutex);
334 spin_lock_init(&sbi->fs_lock);
335 sbi->queues = NULL;
336 spin_lock_init(&sbi->rehash_lock);
337 INIT_LIST_HEAD(&sbi->rehash_list);
338 s->s_blocksize = 1024;
339 s->s_blocksize_bits = 10;
340 s->s_magic = AUTOFS_SUPER_MAGIC;
341 s->s_op = &autofs4_sops;
342 s->s_time_gran = 1;
343
344
345
346
347 ino = autofs4_mkroot(sbi);
348 if (!ino)
349 goto fail_free;
350 root_inode = autofs4_get_inode(s, ino);
351 if (!root_inode)
352 goto fail_ino;
353
354 root = d_alloc_root(root_inode);
355 if (!root)
356 goto fail_iput;
357 pipe = NULL;
358
359 root->d_op = &autofs4_sb_dentry_operations;
360 root->d_fsdata = ino;
361
362
363 if (parse_options(data, &pipefd, &root_inode->i_uid, &root_inode->i_gid,
364 &sbi->oz_pgrp, &sbi->type, &sbi->min_proto,
365 &sbi->max_proto)) {
366 printk("autofs: called with bogus options\n");
367 goto fail_dput;
368 }
369
370 root_inode->i_fop = &autofs4_root_operations;
371 root_inode->i_op = sbi->type & AUTOFS_TYPE_DIRECT ?
372 &autofs4_direct_root_inode_operations :
373 &autofs4_indirect_root_inode_operations;
374
375
376 if (sbi->max_proto < AUTOFS_MIN_PROTO_VERSION ||
377 sbi->min_proto > AUTOFS_MAX_PROTO_VERSION) {
378 printk("autofs: kernel does not match daemon version "
379 "daemon (%d, %d) kernel (%d, %d)\n",
380 sbi->min_proto, sbi->max_proto,
381 AUTOFS_MIN_PROTO_VERSION, AUTOFS_MAX_PROTO_VERSION);
382 goto fail_dput;
383 }
384
385
386 if (sbi->max_proto > AUTOFS_MAX_PROTO_VERSION)
387 sbi->version = AUTOFS_MAX_PROTO_VERSION;
388 else
389 sbi->version = sbi->max_proto;
390 sbi->sub_version = AUTOFS_PROTO_SUBVERSION;
391
392 DPRINTK("pipe fd = %d, pgrp = %u", pipefd, sbi->oz_pgrp);
393 pipe = fget(pipefd);
394
395 if (!pipe) {
396 printk("autofs: could not open pipe file descriptor\n");
397 goto fail_dput;
398 }
399 if (!pipe->f_op || !pipe->f_op->write)
400 goto fail_fput;
401 sbi->pipe = pipe;
402 sbi->pipefd = pipefd;
403 sbi->catatonic = 0;
404
405
406
407
408 s->s_root = root;
409 return 0;
410
411
412
413
414fail_fput:
415 printk("autofs: pipe file descriptor does not contain proper ops\n");
416 fput(pipe);
417
418fail_dput:
419 dput(root);
420 goto fail_free;
421fail_iput:
422 printk("autofs: get root dentry failed\n");
423 iput(root_inode);
424fail_ino:
425 kfree(ino);
426fail_free:
427 kfree(sbi);
428 s->s_fs_info = NULL;
429fail_unlock:
430 return -EINVAL;
431}
432
433struct inode *autofs4_get_inode(struct super_block *sb,
434 struct autofs_info *inf)
435{
436 struct inode *inode = new_inode(sb);
437
438 if (inode == NULL)
439 return NULL;
440
441 inf->inode = inode;
442 inode->i_mode = inf->mode;
443 if (sb->s_root) {
444 inode->i_uid = sb->s_root->d_inode->i_uid;
445 inode->i_gid = sb->s_root->d_inode->i_gid;
446 } else {
447 inode->i_uid = 0;
448 inode->i_gid = 0;
449 }
450 inode->i_blocks = 0;
451 inode->i_atime = inode->i_mtime = inode->i_ctime = CURRENT_TIME;
452
453 if (S_ISDIR(inf->mode)) {
454 inode->i_nlink = 2;
455 inode->i_op = &autofs4_dir_inode_operations;
456 inode->i_fop = &autofs4_dir_operations;
457 } else if (S_ISLNK(inf->mode)) {
458 inode->i_size = inf->size;
459 inode->i_op = &autofs4_symlink_inode_operations;
460 }
461
462 return inode;
463}
464
