blob: dda510d31f840dbba96834619a668f723bc99e16 [file] [log] [blame]
Linus Torvalds1da177e2005-04-16 15:20:36 -07001/* -*- linux-c -*- --------------------------------------------------------- *
2 *
3 * linux/fs/autofs/inode.c
4 *
5 * Copyright 1997-1998 Transmeta Corporation -- All Rights Reserved
6 *
7 * This file is part of the Linux kernel and is made available under
8 * the terms of the GNU General Public License, version 2, or at your
9 * option, any later version, incorporated herein by reference.
10 *
11 * ------------------------------------------------------------------------- */
12
13#include <linux/kernel.h>
14#include <linux/mm.h>
15#include <linux/slab.h>
16#include <linux/file.h>
17#include <linux/parser.h>
18#include <linux/bitops.h>
Jeff Garzike18fa702006-09-24 11:13:19 -040019#include <linux/magic.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070020#include "autofs_i.h"
21#include <linux/module.h>
22
David Howells0e7d7382006-10-19 23:28:36 -070023void autofs_kill_sb(struct super_block *sb)
Linus Torvalds1da177e2005-04-16 15:20:36 -070024{
25 struct autofs_sb_info *sbi = autofs_sbi(sb);
26 unsigned int n;
27
Ian Kentba8df432006-11-14 02:03:29 -080028 /*
29 * In the event of a failure in get_sb_nodev the superblock
30 * info is not present so nothing else has been setup, so
Jiri Kosinac949d4e2006-12-06 20:39:38 -080031 * just call kill_anon_super when we are called from
32 * deactivate_super.
Ian Kentba8df432006-11-14 02:03:29 -080033 */
34 if (!sbi)
Jiri Kosinac949d4e2006-12-06 20:39:38 -080035 goto out_kill_sb;
Ian Kentba8df432006-11-14 02:03:29 -080036
Sukadev Bhattiprolud78e53c2007-05-10 22:23:06 -070037 if (!sbi->catatonic)
Linus Torvalds1da177e2005-04-16 15:20:36 -070038 autofs_catatonic_mode(sbi); /* Free wait queues, close pipe */
39
Sukadev Bhattiprolufa0334f2007-05-10 22:23:08 -070040 put_pid(sbi->oz_pgrp);
41
Alexander Krizhanovskyf76baf92005-09-09 13:01:59 -070042 autofs_hash_nuke(sbi);
Sukadev Bhattiprolud78e53c2007-05-10 22:23:06 -070043 for (n = 0; n < AUTOFS_MAX_SYMLINKS; n++) {
44 if (test_bit(n, sbi->symlink_bitmap))
Linus Torvalds1da177e2005-04-16 15:20:36 -070045 kfree(sbi->symlink[n].data);
46 }
47
48 kfree(sb->s_fs_info);
49
Jiri Kosinac949d4e2006-12-06 20:39:38 -080050out_kill_sb:
Linus Torvalds1da177e2005-04-16 15:20:36 -070051 DPRINTK(("autofs: shutting down\n"));
David Howells0e7d7382006-10-19 23:28:36 -070052 kill_anon_super(sb);
Linus Torvalds1da177e2005-04-16 15:20:36 -070053}
54
Josef 'Jeff' Sipekee9b6d62007-02-12 00:55:41 -080055static const struct super_operations autofs_sops = {
Linus Torvalds1da177e2005-04-16 15:20:36 -070056 .statfs = simple_statfs,
Miklos Szeredi979db752008-02-08 04:21:38 -080057 .show_options = generic_show_options,
Linus Torvalds1da177e2005-04-16 15:20:36 -070058};
59
60enum {Opt_err, Opt_fd, Opt_uid, Opt_gid, Opt_pgrp, Opt_minproto, Opt_maxproto};
61
62static match_table_t autofs_tokens = {
63 {Opt_fd, "fd=%u"},
64 {Opt_uid, "uid=%u"},
65 {Opt_gid, "gid=%u"},
66 {Opt_pgrp, "pgrp=%u"},
67 {Opt_minproto, "minproto=%u"},
68 {Opt_maxproto, "maxproto=%u"},
69 {Opt_err, NULL}
70};
71
Sukadev Bhattiprolud78e53c2007-05-10 22:23:06 -070072static int parse_options(char *options, int *pipefd, uid_t *uid, gid_t *gid,
73 pid_t *pgrp, int *minproto, int *maxproto)
Linus Torvalds1da177e2005-04-16 15:20:36 -070074{
75 char *p;
76 substring_t args[MAX_OPT_ARGS];
77 int option;
78
79 *uid = current->uid;
80 *gid = current->gid;
Pavel Emelianova47afb02007-10-18 23:39:46 -070081 *pgrp = task_pgrp_nr(current);
Linus Torvalds1da177e2005-04-16 15:20:36 -070082
83 *minproto = *maxproto = AUTOFS_PROTO_VERSION;
84
85 *pipefd = -1;
86
87 if (!options)
88 return 1;
89
90 while ((p = strsep(&options, ",")) != NULL) {
91 int token;
92 if (!*p)
93 continue;
94
95 token = match_token(p, autofs_tokens, args);
96 switch (token) {
97 case Opt_fd:
98 if (match_int(&args[0], &option))
99 return 1;
100 *pipefd = option;
101 break;
102 case Opt_uid:
103 if (match_int(&args[0], &option))
104 return 1;
105 *uid = option;
106 break;
107 case Opt_gid:
108 if (match_int(&args[0], &option))
109 return 1;
110 *gid = option;
111 break;
112 case Opt_pgrp:
113 if (match_int(&args[0], &option))
114 return 1;
115 *pgrp = option;
116 break;
117 case Opt_minproto:
118 if (match_int(&args[0], &option))
119 return 1;
120 *minproto = option;
121 break;
122 case Opt_maxproto:
123 if (match_int(&args[0], &option))
124 return 1;
125 *maxproto = option;
126 break;
127 default:
128 return 1;
129 }
130 }
131 return (*pipefd < 0);
132}
133
134int autofs_fill_super(struct super_block *s, void *data, int silent)
135{
136 struct inode * root_inode;
137 struct dentry * root;
138 struct file * pipe;
139 int pipefd;
140 struct autofs_sb_info *sbi;
141 int minproto, maxproto;
Sukadev Bhattiprolufa0334f2007-05-10 22:23:08 -0700142 pid_t pgid;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700143
Miklos Szeredi979db752008-02-08 04:21:38 -0800144 save_mount_options(s, data);
145
Panagiotis Issarisf8314dc2006-09-27 01:49:37 -0700146 sbi = kzalloc(sizeof(*sbi), GFP_KERNEL);
Sukadev Bhattiprolud78e53c2007-05-10 22:23:06 -0700147 if (!sbi)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700148 goto fail_unlock;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700149 DPRINTK(("autofs: starting up, sbi = %p\n",sbi));
150
151 s->s_fs_info = sbi;
152 sbi->magic = AUTOFS_SBI_MAGIC;
Ian Kentba8df432006-11-14 02:03:29 -0800153 sbi->pipe = NULL;
154 sbi->catatonic = 1;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700155 sbi->exp_timeout = 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700156 autofs_initialize_hash(&sbi->dirhash);
157 sbi->queues = NULL;
158 memset(sbi->symlink_bitmap, 0, sizeof(long)*AUTOFS_SYMLINK_BITMAP_LEN);
159 sbi->next_dir_ino = AUTOFS_FIRST_DIR_INO;
160 s->s_blocksize = 1024;
161 s->s_blocksize_bits = 10;
162 s->s_magic = AUTOFS_SUPER_MAGIC;
163 s->s_op = &autofs_sops;
164 s->s_time_gran = 1;
Alexander Krizhanovskyf76baf92005-09-09 13:01:59 -0700165 sbi->sb = s;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700166
David Howells62328a02008-02-07 00:15:30 -0800167 root_inode = autofs_iget(s, AUTOFS_ROOT_INO);
168 if (IS_ERR(root_inode))
169 goto fail_free;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700170 root = d_alloc_root(root_inode);
171 pipe = NULL;
172
173 if (!root)
174 goto fail_iput;
175
176 /* Can this call block? - WTF cares? s is locked. */
Sukadev Bhattiprolud78e53c2007-05-10 22:23:06 -0700177 if (parse_options(data, &pipefd, &root_inode->i_uid,
Sukadev Bhattiprolufa0334f2007-05-10 22:23:08 -0700178 &root_inode->i_gid, &pgid, &minproto,
Sukadev Bhattiprolud78e53c2007-05-10 22:23:06 -0700179 &maxproto)) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700180 printk("autofs: called with bogus options\n");
181 goto fail_dput;
182 }
183
184 /* Couldn't this be tested earlier? */
Sukadev Bhattiprolud78e53c2007-05-10 22:23:06 -0700185 if (minproto > AUTOFS_PROTO_VERSION ||
186 maxproto < AUTOFS_PROTO_VERSION) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700187 printk("autofs: kernel does not match daemon version\n");
188 goto fail_dput;
189 }
190
Sukadev Bhattiprolufa0334f2007-05-10 22:23:08 -0700191 DPRINTK(("autofs: pipe fd = %d, pgrp = %u\n", pipefd, pgid));
192 sbi->oz_pgrp = find_get_pid(pgid);
193
194 if (!sbi->oz_pgrp) {
195 printk("autofs: could not find process group %d\n", pgid);
196 goto fail_dput;
197 }
198
Linus Torvalds1da177e2005-04-16 15:20:36 -0700199 pipe = fget(pipefd);
200
Sukadev Bhattiprolud78e53c2007-05-10 22:23:06 -0700201 if (!pipe) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700202 printk("autofs: could not open pipe file descriptor\n");
Sukadev Bhattiprolufa0334f2007-05-10 22:23:08 -0700203 goto fail_put_pid;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700204 }
Sukadev Bhattiprolufa0334f2007-05-10 22:23:08 -0700205
Sukadev Bhattiprolud78e53c2007-05-10 22:23:06 -0700206 if (!pipe->f_op || !pipe->f_op->write)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700207 goto fail_fput;
208 sbi->pipe = pipe;
Ian Kentba8df432006-11-14 02:03:29 -0800209 sbi->catatonic = 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700210
211 /*
212 * Success! Install the root dentry now to indicate completion.
213 */
214 s->s_root = root;
215 return 0;
216
217fail_fput:
218 printk("autofs: pipe file descriptor does not contain proper ops\n");
219 fput(pipe);
Sukadev Bhattiprolufa0334f2007-05-10 22:23:08 -0700220fail_put_pid:
221 put_pid(sbi->oz_pgrp);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700222fail_dput:
223 dput(root);
224 goto fail_free;
225fail_iput:
226 printk("autofs: get root dentry failed\n");
227 iput(root_inode);
228fail_free:
229 kfree(sbi);
Ian Kentba8df432006-11-14 02:03:29 -0800230 s->s_fs_info = NULL;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700231fail_unlock:
232 return -EINVAL;
233}
234
David Howells62328a02008-02-07 00:15:30 -0800235struct inode *autofs_iget(struct super_block *sb, unsigned long ino)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700236{
Linus Torvalds1da177e2005-04-16 15:20:36 -0700237 unsigned int n;
David Howells62328a02008-02-07 00:15:30 -0800238 struct autofs_sb_info *sbi = autofs_sbi(sb);
239 struct inode *inode;
240
241 inode = iget_locked(sb, ino);
242 if (!inode)
243 return ERR_PTR(-ENOMEM);
244 if (!(inode->i_state & I_NEW))
245 return inode;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700246
247 /* Initialize to the default case (stub directory) */
248
249 inode->i_op = &simple_dir_inode_operations;
250 inode->i_fop = &simple_dir_operations;
251 inode->i_mode = S_IFDIR | S_IRUGO | S_IXUGO;
252 inode->i_nlink = 2;
253 inode->i_mtime = inode->i_atime = inode->i_ctime = CURRENT_TIME;
254 inode->i_blocks = 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700255
Sukadev Bhattiprolud78e53c2007-05-10 22:23:06 -0700256 if (ino == AUTOFS_ROOT_INO) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700257 inode->i_mode = S_IFDIR | S_IRUGO | S_IXUGO | S_IWUSR;
258 inode->i_op = &autofs_root_inode_operations;
259 inode->i_fop = &autofs_root_operations;
260 inode->i_uid = inode->i_gid = 0; /* Changed in read_super */
David Howells62328a02008-02-07 00:15:30 -0800261 goto done;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700262 }
263
264 inode->i_uid = inode->i_sb->s_root->d_inode->i_uid;
265 inode->i_gid = inode->i_sb->s_root->d_inode->i_gid;
266
Sukadev Bhattiprolud78e53c2007-05-10 22:23:06 -0700267 if (ino >= AUTOFS_FIRST_SYMLINK && ino < AUTOFS_FIRST_DIR_INO) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700268 /* Symlink inode - should be in symlink list */
269 struct autofs_symlink *sl;
270
271 n = ino - AUTOFS_FIRST_SYMLINK;
Sukadev Bhattiprolud78e53c2007-05-10 22:23:06 -0700272 if (n >= AUTOFS_MAX_SYMLINKS || !test_bit(n,sbi->symlink_bitmap)) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700273 printk("autofs: Looking for bad symlink inode %u\n", (unsigned int) ino);
David Howells62328a02008-02-07 00:15:30 -0800274 goto done;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700275 }
276
277 inode->i_op = &autofs_symlink_inode_operations;
278 sl = &sbi->symlink[n];
Theodore Ts'o8e18e292006-09-27 01:50:46 -0700279 inode->i_private = sl;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700280 inode->i_mode = S_IFLNK | S_IRWXUGO;
281 inode->i_mtime.tv_sec = inode->i_ctime.tv_sec = sl->mtime;
282 inode->i_mtime.tv_nsec = inode->i_ctime.tv_nsec = 0;
283 inode->i_size = sl->len;
284 inode->i_nlink = 1;
285 }
David Howells62328a02008-02-07 00:15:30 -0800286
287done:
288 unlock_new_inode(inode);
289 return inode;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700290}