blob: 821b2b955dac2c7b847a91d7abc91d4e0162c838 [file] [log] [blame]
Linus Torvalds1da177e2005-04-16 15:20:36 -07001/* -*- c -*- --------------------------------------------------------------- *
2 *
3 * linux/fs/autofs/inode.c
4 *
5 * Copyright 1997-1998 Transmeta Corporation -- All Rights Reserved
Ian Kent34ca9592006-03-27 01:14:54 -08006 * Copyright 2005-2006 Ian Kent <raven@themaw.net>
Linus Torvalds1da177e2005-04-16 15:20:36 -07007 *
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>
Ian Kentd7c4a5f2006-03-27 01:14:49 -080017#include <linux/seq_file.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070018#include <linux/pagemap.h>
19#include <linux/parser.h>
20#include <linux/bitops.h>
Jeff Garzike18fa702006-09-24 11:13:19 -040021#include <linux/magic.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070022#include "autofs_i.h"
23#include <linux/module.h>
24
25static void ino_lnkfree(struct autofs_info *ino)
26{
Ian Kent25767372008-07-23 21:30:12 -070027 if (ino->u.symlink) {
28 kfree(ino->u.symlink);
29 ino->u.symlink = NULL;
30 }
Linus Torvalds1da177e2005-04-16 15:20:36 -070031}
32
33struct autofs_info *autofs4_init_ino(struct autofs_info *ino,
34 struct autofs_sb_info *sbi, mode_t mode)
35{
36 int reinit = 1;
37
38 if (ino == NULL) {
39 reinit = 0;
40 ino = kmalloc(sizeof(*ino), GFP_KERNEL);
41 }
42
43 if (ino == NULL)
44 return NULL;
45
Ian Kent25767372008-07-23 21:30:12 -070046 if (!reinit) {
47 ino->flags = 0;
48 ino->inode = NULL;
49 ino->dentry = NULL;
50 ino->size = 0;
51 INIT_LIST_HEAD(&ino->active);
Ian Kent4f8427d2009-12-15 16:45:42 -080052 ino->active_count = 0;
Ian Kent25767372008-07-23 21:30:12 -070053 INIT_LIST_HEAD(&ino->expiring);
54 atomic_set(&ino->count, 0);
55 }
56
Ian Kentc0f54d32008-10-15 22:02:52 -070057 ino->uid = 0;
58 ino->gid = 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -070059 ino->mode = mode;
Linus Torvalds1da177e2005-04-16 15:20:36 -070060 ino->last_used = jiffies;
61
62 ino->sbi = sbi;
63
64 if (reinit && ino->free)
65 (ino->free)(ino);
66
67 memset(&ino->u, 0, sizeof(ino->u));
68
69 ino->free = NULL;
70
71 if (S_ISLNK(mode))
72 ino->free = ino_lnkfree;
73
74 return ino;
75}
76
77void autofs4_free_ino(struct autofs_info *ino)
78{
Ian Kent1aff3c82006-03-27 01:14:46 -080079 struct autofs_info *p_ino;
80
Linus Torvalds1da177e2005-04-16 15:20:36 -070081 if (ino->dentry) {
82 ino->dentry->d_fsdata = NULL;
Ian Kent1aff3c82006-03-27 01:14:46 -080083 if (ino->dentry->d_inode) {
84 struct dentry *parent = ino->dentry->d_parent;
85 if (atomic_dec_and_test(&ino->count)) {
86 p_ino = autofs4_dentry_ino(parent);
87 if (p_ino && parent != ino->dentry)
88 atomic_dec(&p_ino->count);
89 }
Linus Torvalds1da177e2005-04-16 15:20:36 -070090 dput(ino->dentry);
Ian Kent1aff3c82006-03-27 01:14:46 -080091 }
Linus Torvalds1da177e2005-04-16 15:20:36 -070092 ino->dentry = NULL;
93 }
94 if (ino->free)
95 (ino->free)(ino);
96 kfree(ino);
97}
98
David Howells6ce31522006-10-11 01:22:15 -070099void autofs4_kill_sb(struct super_block *sb)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700100{
101 struct autofs_sb_info *sbi = autofs4_sbi(sb);
102
Ian Kentba8df432006-11-14 02:03:29 -0800103 /*
104 * In the event of a failure in get_sb_nodev the superblock
105 * info is not present so nothing else has been setup, so
Jiri Kosinac949d4e2006-12-06 20:39:38 -0800106 * just call kill_anon_super when we are called from
107 * deactivate_super.
Ian Kentba8df432006-11-14 02:03:29 -0800108 */
109 if (!sbi)
Jiri Kosinac949d4e2006-12-06 20:39:38 -0800110 goto out_kill_sb;
Ian Kentba8df432006-11-14 02:03:29 -0800111
Ian Kent5a11d4d2008-07-23 21:30:17 -0700112 /* Free wait queues, close pipe */
113 autofs4_catatonic_mode(sbi);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700114
Ian Kentf50b6f82007-02-20 13:58:10 -0800115 sb->s_fs_info = NULL;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700116 kfree(sbi);
117
Jiri Kosinac949d4e2006-12-06 20:39:38 -0800118out_kill_sb:
Linus Torvalds1da177e2005-04-16 15:20:36 -0700119 DPRINTK("shutting down");
Al Viro5b7e9342010-01-24 00:28:52 -0500120 kill_litter_super(sb);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700121}
122
Ian Kentd7c4a5f2006-03-27 01:14:49 -0800123static int autofs4_show_options(struct seq_file *m, struct vfsmount *mnt)
124{
125 struct autofs_sb_info *sbi = autofs4_sbi(mnt->mnt_sb);
Miklos Szerediaef97cb2008-02-08 04:21:37 -0800126 struct inode *root_inode = mnt->mnt_sb->s_root->d_inode;
Ian Kentd7c4a5f2006-03-27 01:14:49 -0800127
128 if (!sbi)
129 return 0;
130
131 seq_printf(m, ",fd=%d", sbi->pipefd);
Miklos Szerediaef97cb2008-02-08 04:21:37 -0800132 if (root_inode->i_uid != 0)
133 seq_printf(m, ",uid=%u", root_inode->i_uid);
134 if (root_inode->i_gid != 0)
135 seq_printf(m, ",gid=%u", root_inode->i_gid);
Ian Kentd7c4a5f2006-03-27 01:14:49 -0800136 seq_printf(m, ",pgrp=%d", sbi->oz_pgrp);
137 seq_printf(m, ",timeout=%lu", sbi->exp_timeout/HZ);
138 seq_printf(m, ",minproto=%d", sbi->min_proto);
139 seq_printf(m, ",maxproto=%d", sbi->max_proto);
140
Ian Kenta92daf62009-01-06 14:42:08 -0800141 if (autofs_type_offset(sbi->type))
Ian Kent34ca9592006-03-27 01:14:54 -0800142 seq_printf(m, ",offset");
Ian Kenta92daf62009-01-06 14:42:08 -0800143 else if (autofs_type_direct(sbi->type))
Ian Kent34ca9592006-03-27 01:14:54 -0800144 seq_printf(m, ",direct");
145 else
146 seq_printf(m, ",indirect");
147
Ian Kentd7c4a5f2006-03-27 01:14:49 -0800148 return 0;
149}
150
Josef 'Jeff' Sipekee9b6d62007-02-12 00:55:41 -0800151static const struct super_operations autofs4_sops = {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700152 .statfs = simple_statfs,
Ian Kentd7c4a5f2006-03-27 01:14:49 -0800153 .show_options = autofs4_show_options,
Linus Torvalds1da177e2005-04-16 15:20:36 -0700154};
155
Ian Kent34ca9592006-03-27 01:14:54 -0800156enum {Opt_err, Opt_fd, Opt_uid, Opt_gid, Opt_pgrp, Opt_minproto, Opt_maxproto,
157 Opt_indirect, Opt_direct, Opt_offset};
Linus Torvalds1da177e2005-04-16 15:20:36 -0700158
Steven Whitehousea447c092008-10-13 10:46:57 +0100159static const match_table_t tokens = {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700160 {Opt_fd, "fd=%u"},
161 {Opt_uid, "uid=%u"},
162 {Opt_gid, "gid=%u"},
163 {Opt_pgrp, "pgrp=%u"},
164 {Opt_minproto, "minproto=%u"},
165 {Opt_maxproto, "maxproto=%u"},
Ian Kent34ca9592006-03-27 01:14:54 -0800166 {Opt_indirect, "indirect"},
167 {Opt_direct, "direct"},
168 {Opt_offset, "offset"},
Linus Torvalds1da177e2005-04-16 15:20:36 -0700169 {Opt_err, NULL}
170};
171
172static int parse_options(char *options, int *pipefd, uid_t *uid, gid_t *gid,
Sukadev Bhattiprolud78e53c2007-05-10 22:23:06 -0700173 pid_t *pgrp, unsigned int *type, int *minproto, int *maxproto)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700174{
175 char *p;
176 substring_t args[MAX_OPT_ARGS];
177 int option;
178
David Howells0eb790e2008-11-14 10:38:46 +1100179 *uid = current_uid();
180 *gid = current_gid();
Pavel Emelianova47afb02007-10-18 23:39:46 -0700181 *pgrp = task_pgrp_nr(current);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700182
183 *minproto = AUTOFS_MIN_PROTO_VERSION;
184 *maxproto = AUTOFS_MAX_PROTO_VERSION;
185
186 *pipefd = -1;
187
188 if (!options)
189 return 1;
190
191 while ((p = strsep(&options, ",")) != NULL) {
192 int token;
193 if (!*p)
194 continue;
195
196 token = match_token(p, tokens, args);
197 switch (token) {
198 case Opt_fd:
199 if (match_int(args, pipefd))
200 return 1;
201 break;
202 case Opt_uid:
203 if (match_int(args, &option))
204 return 1;
205 *uid = option;
206 break;
207 case Opt_gid:
208 if (match_int(args, &option))
209 return 1;
210 *gid = option;
211 break;
212 case Opt_pgrp:
213 if (match_int(args, &option))
214 return 1;
215 *pgrp = option;
216 break;
217 case Opt_minproto:
218 if (match_int(args, &option))
219 return 1;
220 *minproto = option;
221 break;
222 case Opt_maxproto:
223 if (match_int(args, &option))
224 return 1;
225 *maxproto = option;
226 break;
Ian Kent34ca9592006-03-27 01:14:54 -0800227 case Opt_indirect:
Ian Kenta92daf62009-01-06 14:42:08 -0800228 set_autofs_type_indirect(type);
Ian Kent34ca9592006-03-27 01:14:54 -0800229 break;
230 case Opt_direct:
Ian Kenta92daf62009-01-06 14:42:08 -0800231 set_autofs_type_direct(type);
Ian Kent34ca9592006-03-27 01:14:54 -0800232 break;
233 case Opt_offset:
Ian Kenta92daf62009-01-06 14:42:08 -0800234 set_autofs_type_offset(type);
Ian Kent34ca9592006-03-27 01:14:54 -0800235 break;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700236 default:
237 return 1;
238 }
239 }
240 return (*pipefd < 0);
241}
242
243static struct autofs_info *autofs4_mkroot(struct autofs_sb_info *sbi)
244{
245 struct autofs_info *ino;
246
247 ino = autofs4_init_ino(NULL, sbi, S_IFDIR | 0755);
248 if (!ino)
249 return NULL;
250
251 return ino;
252}
253
Al Viro08f11512009-02-20 05:56:19 +0000254static const struct dentry_operations autofs4_sb_dentry_operations = {
Ian Kent34ca9592006-03-27 01:14:54 -0800255 .d_release = autofs4_dentry_release,
256};
257
Linus Torvalds1da177e2005-04-16 15:20:36 -0700258int autofs4_fill_super(struct super_block *s, void *data, int silent)
259{
260 struct inode * root_inode;
261 struct dentry * root;
262 struct file * pipe;
263 int pipefd;
264 struct autofs_sb_info *sbi;
265 struct autofs_info *ino;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700266
Mariusz Kozlowskib63d50c2007-10-16 23:26:44 -0700267 sbi = kzalloc(sizeof(*sbi), GFP_KERNEL);
Sukadev Bhattiprolud78e53c2007-05-10 22:23:06 -0700268 if (!sbi)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700269 goto fail_unlock;
270 DPRINTK("starting up, sbi = %p",sbi);
271
Linus Torvalds1da177e2005-04-16 15:20:36 -0700272 s->s_fs_info = sbi;
273 sbi->magic = AUTOFS_SBI_MAGIC;
Ian Kentd7c4a5f2006-03-27 01:14:49 -0800274 sbi->pipefd = -1;
Ian Kentba8df432006-11-14 02:03:29 -0800275 sbi->pipe = NULL;
276 sbi->catatonic = 1;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700277 sbi->exp_timeout = 0;
Pavel Emelianova47afb02007-10-18 23:39:46 -0700278 sbi->oz_pgrp = task_pgrp_nr(current);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700279 sbi->sb = s;
280 sbi->version = 0;
281 sbi->sub_version = 0;
Ian Kenta92daf62009-01-06 14:42:08 -0800282 set_autofs_type_indirect(&sbi->type);
Ian Kentd7c4a5f2006-03-27 01:14:49 -0800283 sbi->min_proto = 0;
284 sbi->max_proto = 0;
Ingo Molnar1d5599e2006-03-23 03:00:41 -0800285 mutex_init(&sbi->wq_mutex);
Ian Kent3a9720c2005-05-01 08:59:17 -0700286 spin_lock_init(&sbi->fs_lock);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700287 sbi->queues = NULL;
Ian Kent5f6f4f22008-07-23 21:30:09 -0700288 spin_lock_init(&sbi->lookup_lock);
Ian Kent25767372008-07-23 21:30:12 -0700289 INIT_LIST_HEAD(&sbi->active_list);
Ian Kent5f6f4f22008-07-23 21:30:09 -0700290 INIT_LIST_HEAD(&sbi->expiring_list);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700291 s->s_blocksize = 1024;
292 s->s_blocksize_bits = 10;
293 s->s_magic = AUTOFS_SUPER_MAGIC;
294 s->s_op = &autofs4_sops;
295 s->s_time_gran = 1;
296
297 /*
298 * Get the root inode and dentry, but defer checking for errors.
299 */
300 ino = autofs4_mkroot(sbi);
301 if (!ino)
302 goto fail_free;
303 root_inode = autofs4_get_inode(s, ino);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700304 if (!root_inode)
Ian Kent34ca9592006-03-27 01:14:54 -0800305 goto fail_ino;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700306
Linus Torvalds1da177e2005-04-16 15:20:36 -0700307 root = d_alloc_root(root_inode);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700308 if (!root)
309 goto fail_iput;
Ian Kent34ca9592006-03-27 01:14:54 -0800310 pipe = NULL;
311
312 root->d_op = &autofs4_sb_dentry_operations;
313 root->d_fsdata = ino;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700314
315 /* Can this call block? */
Sukadev Bhattiprolud78e53c2007-05-10 22:23:06 -0700316 if (parse_options(data, &pipefd, &root_inode->i_uid, &root_inode->i_gid,
317 &sbi->oz_pgrp, &sbi->type, &sbi->min_proto,
318 &sbi->max_proto)) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700319 printk("autofs: called with bogus options\n");
320 goto fail_dput;
321 }
322
Ian Kent34ca9592006-03-27 01:14:54 -0800323 root_inode->i_fop = &autofs4_root_operations;
Ian Kenta92daf62009-01-06 14:42:08 -0800324 root_inode->i_op = autofs_type_trigger(sbi->type) ?
Ian Kent34ca9592006-03-27 01:14:54 -0800325 &autofs4_direct_root_inode_operations :
326 &autofs4_indirect_root_inode_operations;
327
Linus Torvalds1da177e2005-04-16 15:20:36 -0700328 /* Couldn't this be tested earlier? */
Ian Kentd7c4a5f2006-03-27 01:14:49 -0800329 if (sbi->max_proto < AUTOFS_MIN_PROTO_VERSION ||
330 sbi->min_proto > AUTOFS_MAX_PROTO_VERSION) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700331 printk("autofs: kernel does not match daemon version "
332 "daemon (%d, %d) kernel (%d, %d)\n",
Ian Kentd7c4a5f2006-03-27 01:14:49 -0800333 sbi->min_proto, sbi->max_proto,
Linus Torvalds1da177e2005-04-16 15:20:36 -0700334 AUTOFS_MIN_PROTO_VERSION, AUTOFS_MAX_PROTO_VERSION);
335 goto fail_dput;
336 }
337
Ian Kentd7c4a5f2006-03-27 01:14:49 -0800338 /* Establish highest kernel protocol version */
339 if (sbi->max_proto > AUTOFS_MAX_PROTO_VERSION)
340 sbi->version = AUTOFS_MAX_PROTO_VERSION;
341 else
342 sbi->version = sbi->max_proto;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700343 sbi->sub_version = AUTOFS_PROTO_SUBVERSION;
344
345 DPRINTK("pipe fd = %d, pgrp = %u", pipefd, sbi->oz_pgrp);
346 pipe = fget(pipefd);
347
Sukadev Bhattiprolud78e53c2007-05-10 22:23:06 -0700348 if (!pipe) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700349 printk("autofs: could not open pipe file descriptor\n");
350 goto fail_dput;
351 }
Sukadev Bhattiprolud78e53c2007-05-10 22:23:06 -0700352 if (!pipe->f_op || !pipe->f_op->write)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700353 goto fail_fput;
354 sbi->pipe = pipe;
Ian Kentd7c4a5f2006-03-27 01:14:49 -0800355 sbi->pipefd = pipefd;
Ian Kentba8df432006-11-14 02:03:29 -0800356 sbi->catatonic = 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700357
358 /*
Linus Torvalds1da177e2005-04-16 15:20:36 -0700359 * Success! Install the root dentry now to indicate completion.
360 */
361 s->s_root = root;
362 return 0;
363
364 /*
365 * Failure ... clean up.
366 */
367fail_fput:
368 printk("autofs: pipe file descriptor does not contain proper ops\n");
369 fput(pipe);
370 /* fall through */
371fail_dput:
372 dput(root);
373 goto fail_free;
374fail_iput:
375 printk("autofs: get root dentry failed\n");
376 iput(root_inode);
Ian Kent34ca9592006-03-27 01:14:54 -0800377fail_ino:
378 kfree(ino);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700379fail_free:
380 kfree(sbi);
Ian Kentba8df432006-11-14 02:03:29 -0800381 s->s_fs_info = NULL;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700382fail_unlock:
383 return -EINVAL;
384}
385
386struct inode *autofs4_get_inode(struct super_block *sb,
387 struct autofs_info *inf)
388{
389 struct inode *inode = new_inode(sb);
390
391 if (inode == NULL)
392 return NULL;
393
394 inf->inode = inode;
395 inode->i_mode = inf->mode;
396 if (sb->s_root) {
397 inode->i_uid = sb->s_root->d_inode->i_uid;
398 inode->i_gid = sb->s_root->d_inode->i_gid;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700399 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700400 inode->i_atime = inode->i_mtime = inode->i_ctime = CURRENT_TIME;
401
402 if (S_ISDIR(inf->mode)) {
403 inode->i_nlink = 2;
404 inode->i_op = &autofs4_dir_inode_operations;
405 inode->i_fop = &autofs4_dir_operations;
406 } else if (S_ISLNK(inf->mode)) {
407 inode->i_size = inf->size;
408 inode->i_op = &autofs4_symlink_inode_operations;
409 }
410
411 return inode;
412}