1 /* -*- c -*- --------------------------------------------------------------- *
3 * linux/fs/autofs/inode.c
5 * Copyright 1997-1998 Transmeta Corporation -- All Rights Reserved
6 * Copyright 2005-2006 Ian Kent <raven@themaw.net>
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.
12 * ------------------------------------------------------------------------- */
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/smp_lock.h>
22 #include <linux/magic.h>
24 #include <linux/module.h>
26 static void ino_lnkfree(struct autofs_info
*ino
)
28 kfree(ino
->u
.symlink
);
29 ino
->u
.symlink
= NULL
;
32 struct autofs_info
*autofs4_init_ino(struct autofs_info
*ino
,
33 struct autofs_sb_info
*sbi
, mode_t mode
)
39 ino
= kmalloc(sizeof(*ino
), GFP_KERNEL
);
51 INIT_LIST_HEAD(&ino
->rehash
);
53 ino
->last_used
= jiffies
;
54 atomic_set(&ino
->count
, 0);
58 if (reinit
&& ino
->free
)
61 memset(&ino
->u
, 0, sizeof(ino
->u
));
66 ino
->free
= ino_lnkfree
;
71 void autofs4_free_ino(struct autofs_info
*ino
)
73 struct autofs_info
*p_ino
;
76 ino
->dentry
->d_fsdata
= NULL
;
77 if (ino
->dentry
->d_inode
) {
78 struct dentry
*parent
= ino
->dentry
->d_parent
;
79 if (atomic_dec_and_test(&ino
->count
)) {
80 p_ino
= autofs4_dentry_ino(parent
);
81 if (p_ino
&& parent
!= ino
->dentry
)
82 atomic_dec(&p_ino
->count
);
94 * Deal with the infamous "Busy inodes after umount ..." message.
96 * Clean up the dentry tree. This happens with autofs if the user
97 * space program goes away due to a SIGKILL, SIGSEGV etc.
99 static void autofs4_force_release(struct autofs_sb_info
*sbi
)
101 struct dentry
*this_parent
= sbi
->sb
->s_root
;
102 struct list_head
*next
;
104 if (!sbi
->sb
->s_root
)
107 spin_lock(&dcache_lock
);
109 next
= this_parent
->d_subdirs
.next
;
111 while (next
!= &this_parent
->d_subdirs
) {
112 struct dentry
*dentry
= list_entry(next
, struct dentry
, d_u
.d_child
);
114 /* Negative dentry - don`t care */
115 if (!simple_positive(dentry
)) {
120 if (!list_empty(&dentry
->d_subdirs
)) {
121 this_parent
= dentry
;
126 spin_unlock(&dcache_lock
);
128 DPRINTK("dentry %p %.*s",
129 dentry
, (int)dentry
->d_name
.len
, dentry
->d_name
.name
);
132 spin_lock(&dcache_lock
);
135 if (this_parent
!= sbi
->sb
->s_root
) {
136 struct dentry
*dentry
= this_parent
;
138 next
= this_parent
->d_u
.d_child
.next
;
139 this_parent
= this_parent
->d_parent
;
140 spin_unlock(&dcache_lock
);
141 DPRINTK("parent dentry %p %.*s",
142 dentry
, (int)dentry
->d_name
.len
, dentry
->d_name
.name
);
144 spin_lock(&dcache_lock
);
147 spin_unlock(&dcache_lock
);
150 void autofs4_kill_sb(struct super_block
*sb
)
152 struct autofs_sb_info
*sbi
= autofs4_sbi(sb
);
155 * In the event of a failure in get_sb_nodev the superblock
156 * info is not present so nothing else has been setup, so
157 * just call kill_anon_super when we are called from
164 autofs4_catatonic_mode(sbi
); /* Free wait queues, close pipe */
166 /* Clean up and release dangling references */
167 autofs4_force_release(sbi
);
169 sb
->s_fs_info
= NULL
;
173 DPRINTK("shutting down");
177 static int autofs4_show_options(struct seq_file
*m
, struct vfsmount
*mnt
)
179 struct autofs_sb_info
*sbi
= autofs4_sbi(mnt
->mnt_sb
);
184 seq_printf(m
, ",fd=%d", sbi
->pipefd
);
185 seq_printf(m
, ",pgrp=%d", sbi
->oz_pgrp
);
186 seq_printf(m
, ",timeout=%lu", sbi
->exp_timeout
/HZ
);
187 seq_printf(m
, ",minproto=%d", sbi
->min_proto
);
188 seq_printf(m
, ",maxproto=%d", sbi
->max_proto
);
190 if (sbi
->type
& AUTOFS_TYPE_OFFSET
)
191 seq_printf(m
, ",offset");
192 else if (sbi
->type
& AUTOFS_TYPE_DIRECT
)
193 seq_printf(m
, ",direct");
195 seq_printf(m
, ",indirect");
200 static const struct super_operations autofs4_sops
= {
201 .statfs
= simple_statfs
,
202 .show_options
= autofs4_show_options
,
205 enum {Opt_err
, Opt_fd
, Opt_uid
, Opt_gid
, Opt_pgrp
, Opt_minproto
, Opt_maxproto
,
206 Opt_indirect
, Opt_direct
, Opt_offset
};
208 static match_table_t tokens
= {
212 {Opt_pgrp
, "pgrp=%u"},
213 {Opt_minproto
, "minproto=%u"},
214 {Opt_maxproto
, "maxproto=%u"},
215 {Opt_indirect
, "indirect"},
216 {Opt_direct
, "direct"},
217 {Opt_offset
, "offset"},
221 static int parse_options(char *options
, int *pipefd
, uid_t
*uid
, gid_t
*gid
,
222 pid_t
*pgrp
, unsigned int *type
,
223 int *minproto
, int *maxproto
)
226 substring_t args
[MAX_OPT_ARGS
];
231 *pgrp
= process_group(current
);
233 *minproto
= AUTOFS_MIN_PROTO_VERSION
;
234 *maxproto
= AUTOFS_MAX_PROTO_VERSION
;
241 while ((p
= strsep(&options
, ",")) != NULL
) {
246 token
= match_token(p
, tokens
, args
);
249 if (match_int(args
, pipefd
))
253 if (match_int(args
, &option
))
258 if (match_int(args
, &option
))
263 if (match_int(args
, &option
))
268 if (match_int(args
, &option
))
273 if (match_int(args
, &option
))
278 *type
= AUTOFS_TYPE_INDIRECT
;
281 *type
= AUTOFS_TYPE_DIRECT
;
284 *type
= AUTOFS_TYPE_DIRECT
| AUTOFS_TYPE_OFFSET
;
290 return (*pipefd
< 0);
293 static struct autofs_info
*autofs4_mkroot(struct autofs_sb_info
*sbi
)
295 struct autofs_info
*ino
;
297 ino
= autofs4_init_ino(NULL
, sbi
, S_IFDIR
| 0755);
304 static struct dentry_operations autofs4_sb_dentry_operations
= {
305 .d_release
= autofs4_dentry_release
,
308 int autofs4_fill_super(struct super_block
*s
, void *data
, int silent
)
310 struct inode
* root_inode
;
311 struct dentry
* root
;
314 struct autofs_sb_info
*sbi
;
315 struct autofs_info
*ino
;
317 sbi
= kmalloc(sizeof(*sbi
), GFP_KERNEL
);
320 DPRINTK("starting up, sbi = %p",sbi
);
322 memset(sbi
, 0, sizeof(*sbi
));
325 sbi
->magic
= AUTOFS_SBI_MAGIC
;
329 sbi
->exp_timeout
= 0;
330 sbi
->oz_pgrp
= process_group(current
);
333 sbi
->sub_version
= 0;
337 mutex_init(&sbi
->wq_mutex
);
338 spin_lock_init(&sbi
->fs_lock
);
340 spin_lock_init(&sbi
->rehash_lock
);
341 INIT_LIST_HEAD(&sbi
->rehash_list
);
342 s
->s_blocksize
= 1024;
343 s
->s_blocksize_bits
= 10;
344 s
->s_magic
= AUTOFS_SUPER_MAGIC
;
345 s
->s_op
= &autofs4_sops
;
349 * Get the root inode and dentry, but defer checking for errors.
351 ino
= autofs4_mkroot(sbi
);
354 root_inode
= autofs4_get_inode(s
, ino
);
358 root
= d_alloc_root(root_inode
);
363 root
->d_op
= &autofs4_sb_dentry_operations
;
364 root
->d_fsdata
= ino
;
366 /* Can this call block? */
367 if (parse_options(data
, &pipefd
,
368 &root_inode
->i_uid
, &root_inode
->i_gid
,
369 &sbi
->oz_pgrp
, &sbi
->type
,
370 &sbi
->min_proto
, &sbi
->max_proto
)) {
371 printk("autofs: called with bogus options\n");
375 root_inode
->i_fop
= &autofs4_root_operations
;
376 root_inode
->i_op
= sbi
->type
& AUTOFS_TYPE_DIRECT
?
377 &autofs4_direct_root_inode_operations
:
378 &autofs4_indirect_root_inode_operations
;
380 /* Couldn't this be tested earlier? */
381 if (sbi
->max_proto
< AUTOFS_MIN_PROTO_VERSION
||
382 sbi
->min_proto
> AUTOFS_MAX_PROTO_VERSION
) {
383 printk("autofs: kernel does not match daemon version "
384 "daemon (%d, %d) kernel (%d, %d)\n",
385 sbi
->min_proto
, sbi
->max_proto
,
386 AUTOFS_MIN_PROTO_VERSION
, AUTOFS_MAX_PROTO_VERSION
);
390 /* Establish highest kernel protocol version */
391 if (sbi
->max_proto
> AUTOFS_MAX_PROTO_VERSION
)
392 sbi
->version
= AUTOFS_MAX_PROTO_VERSION
;
394 sbi
->version
= sbi
->max_proto
;
395 sbi
->sub_version
= AUTOFS_PROTO_SUBVERSION
;
397 DPRINTK("pipe fd = %d, pgrp = %u", pipefd
, sbi
->oz_pgrp
);
401 printk("autofs: could not open pipe file descriptor\n");
404 if ( !pipe
->f_op
|| !pipe
->f_op
->write
)
407 sbi
->pipefd
= pipefd
;
411 * Success! Install the root dentry now to indicate completion.
417 * Failure ... clean up.
420 printk("autofs: pipe file descriptor does not contain proper ops\n");
427 printk("autofs: get root dentry failed\n");
438 struct inode
*autofs4_get_inode(struct super_block
*sb
,
439 struct autofs_info
*inf
)
441 struct inode
*inode
= new_inode(sb
);
447 inode
->i_mode
= inf
->mode
;
449 inode
->i_uid
= sb
->s_root
->d_inode
->i_uid
;
450 inode
->i_gid
= sb
->s_root
->d_inode
->i_gid
;
456 inode
->i_atime
= inode
->i_mtime
= inode
->i_ctime
= CURRENT_TIME
;
458 if (S_ISDIR(inf
->mode
)) {
460 inode
->i_op
= &autofs4_dir_inode_operations
;
461 inode
->i_fop
= &autofs4_dir_operations
;
462 } else if (S_ISLNK(inf
->mode
)) {
463 inode
->i_size
= inf
->size
;
464 inode
->i_op
= &autofs4_symlink_inode_operations
;