2 * Copyright (c) 2002 Red Hat, Inc. All rights reserved.
4 * This software may be freely redistributed under the terms of the
5 * GNU General Public License.
7 * You should have received a copy of the GNU General Public License
8 * along with this program; if not, write to the Free Software
9 * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
11 * Authors: David Howells <dhowells@redhat.com>
12 * David Woodhouse <dwmw2@cambridge.redhat.com>
16 #include <linux/kernel.h>
17 #include <linux/module.h>
18 #include <linux/init.h>
19 #include <linux/slab.h>
21 #include <linux/pagemap.h>
25 #include "cmservice.h"
30 #define AFS_FS_MAGIC 0x6B414653 /* 'kAFS' */
32 struct afs_mount_params
{
34 struct afs_cell
*default_cell
;
35 struct afs_volume
*volume
;
38 static void afs_i_init_once(void *foo
, struct kmem_cache
*cachep
,
41 static int afs_get_sb(struct file_system_type
*fs_type
,
42 int flags
, const char *dev_name
,
43 void *data
, struct vfsmount
*mnt
);
45 static struct inode
*afs_alloc_inode(struct super_block
*sb
);
47 static void afs_put_super(struct super_block
*sb
);
49 static void afs_destroy_inode(struct inode
*inode
);
51 struct file_system_type afs_fs_type
= {
55 .kill_sb
= kill_anon_super
,
56 .fs_flags
= FS_BINARY_MOUNTDATA
,
59 static struct super_operations afs_super_ops
= {
60 .statfs
= simple_statfs
,
61 .alloc_inode
= afs_alloc_inode
,
62 .drop_inode
= generic_delete_inode
,
63 .destroy_inode
= afs_destroy_inode
,
64 .clear_inode
= afs_clear_inode
,
65 .put_super
= afs_put_super
,
68 static struct kmem_cache
*afs_inode_cachep
;
69 static atomic_t afs_count_active_inodes
;
71 /*****************************************************************************/
73 * initialise the filesystem
75 int __init
afs_fs_init(void)
81 afs_timer_init(&afs_mntpt_expiry_timer
, &afs_mntpt_expiry_timer_ops
);
83 /* create ourselves an inode cache */
84 atomic_set(&afs_count_active_inodes
, 0);
87 afs_inode_cachep
= kmem_cache_create("afs_inode_cache",
88 sizeof(struct afs_vnode
),
93 if (!afs_inode_cachep
) {
94 printk(KERN_NOTICE
"kAFS: Failed to allocate inode cache\n");
98 /* now export our filesystem to lesser mortals */
99 ret
= register_filesystem(&afs_fs_type
);
101 kmem_cache_destroy(afs_inode_cachep
);
102 kleave(" = %d", ret
);
108 } /* end afs_fs_init() */
110 /*****************************************************************************/
112 * clean up the filesystem
114 void __exit
afs_fs_exit(void)
116 unregister_filesystem(&afs_fs_type
);
118 if (atomic_read(&afs_count_active_inodes
) != 0) {
119 printk("kAFS: %d active inode objects still present\n",
120 atomic_read(&afs_count_active_inodes
));
124 kmem_cache_destroy(afs_inode_cachep
);
126 } /* end afs_fs_exit() */
128 /*****************************************************************************/
130 * check that an argument has a value
132 static int want_arg(char **_value
, const char *option
)
134 if (!_value
|| !*_value
|| !**_value
) {
135 printk(KERN_NOTICE
"kAFS: %s: argument missing\n", option
);
139 } /* end want_arg() */
141 /*****************************************************************************/
143 * check that there's no subsequent value
145 static int want_no_value(char *const *_value
, const char *option
)
147 if (*_value
&& **_value
) {
148 printk(KERN_NOTICE
"kAFS: %s: Invalid argument: %s\n",
153 } /* end want_no_value() */
155 /*****************************************************************************/
157 * parse the mount options
158 * - this function has been shamelessly adapted from the ext3 fs which
159 * shamelessly adapted it from the msdos fs
161 static int afs_super_parse_options(struct afs_mount_params
*params
,
163 const char **devname
)
168 _enter("%s", options
);
170 options
[PAGE_SIZE
- 1] = 0;
173 while ((key
= strsep(&options
, ",")) != 0)
175 value
= strchr(key
, '=');
179 printk("kAFS: KEY: %s, VAL:%s\n", key
, value
?: "-");
181 if (strcmp(key
, "rwpath") == 0) {
182 if (!want_no_value(&value
, "rwpath"))
187 else if (strcmp(key
, "vol") == 0) {
188 if (!want_arg(&value
, "vol"))
193 else if (strcmp(key
, "cell") == 0) {
194 if (!want_arg(&value
, "cell"))
196 afs_put_cell(params
->default_cell
);
197 ret
= afs_cell_lookup(value
,
199 ¶ms
->default_cell
);
205 printk("kAFS: Unknown mount option: '%s'\n", key
);
213 _leave(" = %d", ret
);
215 } /* end afs_super_parse_options() */
217 /*****************************************************************************/
219 * check a superblock to see if it's the one we're looking for
221 static int afs_test_super(struct super_block
*sb
, void *data
)
223 struct afs_mount_params
*params
= data
;
224 struct afs_super_info
*as
= sb
->s_fs_info
;
226 return as
->volume
== params
->volume
;
227 } /* end afs_test_super() */
229 /*****************************************************************************/
231 * fill in the superblock
233 static int afs_fill_super(struct super_block
*sb
, void *data
, int silent
)
235 struct afs_mount_params
*params
= data
;
236 struct afs_super_info
*as
= NULL
;
238 struct dentry
*root
= NULL
;
239 struct inode
*inode
= NULL
;
244 /* allocate a superblock info record */
245 as
= kzalloc(sizeof(struct afs_super_info
), GFP_KERNEL
);
247 _leave(" = -ENOMEM");
251 afs_get_volume(params
->volume
);
252 as
->volume
= params
->volume
;
254 /* fill in the superblock */
255 sb
->s_blocksize
= PAGE_CACHE_SIZE
;
256 sb
->s_blocksize_bits
= PAGE_CACHE_SHIFT
;
257 sb
->s_magic
= AFS_FS_MAGIC
;
258 sb
->s_op
= &afs_super_ops
;
261 /* allocate the root inode and dentry */
262 fid
.vid
= as
->volume
->vid
;
265 ret
= afs_iget(sb
, &fid
, &inode
);
270 root
= d_alloc_root(inode
);
281 afs_put_volume(as
->volume
);
284 sb
->s_fs_info
= NULL
;
286 kleave(" = %d", ret
);
288 } /* end afs_fill_super() */
290 /*****************************************************************************/
292 * get an AFS superblock
293 * - TODO: don't use get_sb_nodev(), but rather call sget() directly
295 static int afs_get_sb(struct file_system_type
*fs_type
,
297 const char *dev_name
,
299 struct vfsmount
*mnt
)
301 struct afs_mount_params params
;
302 struct super_block
*sb
;
305 _enter(",,%s,%p", dev_name
, options
);
307 memset(¶ms
, 0, sizeof(params
));
309 /* start the cache manager */
312 _leave(" = %d", ret
);
316 /* parse the options */
318 ret
= afs_super_parse_options(¶ms
, options
, &dev_name
);
322 printk("kAFS: no volume name specified\n");
328 /* parse the device name */
329 ret
= afs_volume_lookup(dev_name
,
336 /* allocate a deviceless superblock */
337 sb
= sget(fs_type
, afs_test_super
, set_anon_super
, ¶ms
);
343 ret
= afs_fill_super(sb
, ¶ms
, flags
& MS_SILENT
? 1 : 0);
345 up_write(&sb
->s_umount
);
346 deactivate_super(sb
);
349 sb
->s_flags
|= MS_ACTIVE
;
350 simple_set_mnt(mnt
, sb
);
352 afs_put_volume(params
.volume
);
353 afs_put_cell(params
.default_cell
);
354 _leave(" = 0 [%p]", 0, sb
);
358 afs_put_volume(params
.volume
);
359 afs_put_cell(params
.default_cell
);
361 _leave(" = %d", ret
);
363 } /* end afs_get_sb() */
365 /*****************************************************************************/
367 * finish the unmounting process on the superblock
369 static void afs_put_super(struct super_block
*sb
)
371 struct afs_super_info
*as
= sb
->s_fs_info
;
375 afs_put_volume(as
->volume
);
379 } /* end afs_put_super() */
381 /*****************************************************************************/
383 * initialise an inode cache slab element prior to any use
385 static void afs_i_init_once(void *_vnode
, struct kmem_cache
*cachep
,
388 struct afs_vnode
*vnode
= (struct afs_vnode
*) _vnode
;
390 if ((flags
& (SLAB_CTOR_VERIFY
|SLAB_CTOR_CONSTRUCTOR
)) ==
391 SLAB_CTOR_CONSTRUCTOR
) {
392 memset(vnode
, 0, sizeof(*vnode
));
393 inode_init_once(&vnode
->vfs_inode
);
394 init_waitqueue_head(&vnode
->update_waitq
);
395 spin_lock_init(&vnode
->lock
);
396 INIT_LIST_HEAD(&vnode
->cb_link
);
397 INIT_LIST_HEAD(&vnode
->cb_hash_link
);
398 afs_timer_init(&vnode
->cb_timeout
,
399 &afs_vnode_cb_timed_out_ops
);
402 } /* end afs_i_init_once() */
404 /*****************************************************************************/
406 * allocate an AFS inode struct from our slab cache
408 static struct inode
*afs_alloc_inode(struct super_block
*sb
)
410 struct afs_vnode
*vnode
;
412 vnode
= (struct afs_vnode
*)
413 kmem_cache_alloc(afs_inode_cachep
, GFP_KERNEL
);
417 atomic_inc(&afs_count_active_inodes
);
419 memset(&vnode
->fid
, 0, sizeof(vnode
->fid
));
420 memset(&vnode
->status
, 0, sizeof(vnode
->status
));
422 vnode
->volume
= NULL
;
423 vnode
->update_cnt
= 0;
426 return &vnode
->vfs_inode
;
427 } /* end afs_alloc_inode() */
429 /*****************************************************************************/
431 * destroy an AFS inode struct
433 static void afs_destroy_inode(struct inode
*inode
)
435 _enter("{%lu}", inode
->i_ino
);
437 kmem_cache_free(afs_inode_cachep
, AFS_FS_I(inode
));
439 atomic_dec(&afs_count_active_inodes
);
441 } /* end afs_destroy_inode() */