diff options
Diffstat (limited to 'fs/afs/super.c')
-rw-r--r-- | fs/afs/super.c | 441 |
1 files changed, 441 insertions, 0 deletions
diff --git a/fs/afs/super.c b/fs/afs/super.c new file mode 100644 index 000000000000..d6fa8e5999df --- /dev/null +++ b/fs/afs/super.c | |||
@@ -0,0 +1,441 @@ | |||
1 | /* | ||
2 | * Copyright (c) 2002 Red Hat, Inc. All rights reserved. | ||
3 | * | ||
4 | * This software may be freely redistributed under the terms of the | ||
5 | * GNU General Public License. | ||
6 | * | ||
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. | ||
10 | * | ||
11 | * Authors: David Howells <dhowells@redhat.com> | ||
12 | * David Woodhouse <dwmw2@cambridge.redhat.com> | ||
13 | * | ||
14 | */ | ||
15 | |||
16 | #include <linux/kernel.h> | ||
17 | #include <linux/module.h> | ||
18 | #include <linux/init.h> | ||
19 | #include <linux/slab.h> | ||
20 | #include <linux/fs.h> | ||
21 | #include <linux/pagemap.h> | ||
22 | #include "vnode.h" | ||
23 | #include "volume.h" | ||
24 | #include "cell.h" | ||
25 | #include "cmservice.h" | ||
26 | #include "fsclient.h" | ||
27 | #include "super.h" | ||
28 | #include "internal.h" | ||
29 | |||
30 | #define AFS_FS_MAGIC 0x6B414653 /* 'kAFS' */ | ||
31 | |||
32 | struct afs_mount_params { | ||
33 | int rwpath; | ||
34 | struct afs_cell *default_cell; | ||
35 | struct afs_volume *volume; | ||
36 | }; | ||
37 | |||
38 | static void afs_i_init_once(void *foo, kmem_cache_t *cachep, | ||
39 | unsigned long flags); | ||
40 | |||
41 | static struct super_block *afs_get_sb(struct file_system_type *fs_type, | ||
42 | int flags, const char *dev_name, | ||
43 | void *data); | ||
44 | |||
45 | static struct inode *afs_alloc_inode(struct super_block *sb); | ||
46 | |||
47 | static void afs_put_super(struct super_block *sb); | ||
48 | |||
49 | static void afs_destroy_inode(struct inode *inode); | ||
50 | |||
51 | static struct file_system_type afs_fs_type = { | ||
52 | .owner = THIS_MODULE, | ||
53 | .name = "afs", | ||
54 | .get_sb = afs_get_sb, | ||
55 | .kill_sb = kill_anon_super, | ||
56 | .fs_flags = FS_BINARY_MOUNTDATA, | ||
57 | }; | ||
58 | |||
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, | ||
66 | }; | ||
67 | |||
68 | static kmem_cache_t *afs_inode_cachep; | ||
69 | static atomic_t afs_count_active_inodes; | ||
70 | |||
71 | /*****************************************************************************/ | ||
72 | /* | ||
73 | * initialise the filesystem | ||
74 | */ | ||
75 | int __init afs_fs_init(void) | ||
76 | { | ||
77 | int ret; | ||
78 | |||
79 | _enter(""); | ||
80 | |||
81 | afs_timer_init(&afs_mntpt_expiry_timer, &afs_mntpt_expiry_timer_ops); | ||
82 | |||
83 | /* create ourselves an inode cache */ | ||
84 | atomic_set(&afs_count_active_inodes, 0); | ||
85 | |||
86 | ret = -ENOMEM; | ||
87 | afs_inode_cachep = kmem_cache_create("afs_inode_cache", | ||
88 | sizeof(struct afs_vnode), | ||
89 | 0, | ||
90 | SLAB_HWCACHE_ALIGN, | ||
91 | afs_i_init_once, | ||
92 | NULL); | ||
93 | if (!afs_inode_cachep) { | ||
94 | printk(KERN_NOTICE "kAFS: Failed to allocate inode cache\n"); | ||
95 | return ret; | ||
96 | } | ||
97 | |||
98 | /* now export our filesystem to lesser mortals */ | ||
99 | ret = register_filesystem(&afs_fs_type); | ||
100 | if (ret < 0) { | ||
101 | kmem_cache_destroy(afs_inode_cachep); | ||
102 | kleave(" = %d", ret); | ||
103 | return ret; | ||
104 | } | ||
105 | |||
106 | kleave(" = 0"); | ||
107 | return 0; | ||
108 | } /* end afs_fs_init() */ | ||
109 | |||
110 | /*****************************************************************************/ | ||
111 | /* | ||
112 | * clean up the filesystem | ||
113 | */ | ||
114 | void __exit afs_fs_exit(void) | ||
115 | { | ||
116 | unregister_filesystem(&afs_fs_type); | ||
117 | |||
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)); | ||
121 | BUG(); | ||
122 | } | ||
123 | |||
124 | kmem_cache_destroy(afs_inode_cachep); | ||
125 | |||
126 | } /* end afs_fs_exit() */ | ||
127 | |||
128 | /*****************************************************************************/ | ||
129 | /* | ||
130 | * check that an argument has a value | ||
131 | */ | ||
132 | static int want_arg(char **_value, const char *option) | ||
133 | { | ||
134 | if (!_value || !*_value || !**_value) { | ||
135 | printk(KERN_NOTICE "kAFS: %s: argument missing\n", option); | ||
136 | return 0; | ||
137 | } | ||
138 | return 1; | ||
139 | } /* end want_arg() */ | ||
140 | |||
141 | /*****************************************************************************/ | ||
142 | /* | ||
143 | * check that there's no subsequent value | ||
144 | */ | ||
145 | static int want_no_value(char *const *_value, const char *option) | ||
146 | { | ||
147 | if (*_value && **_value) { | ||
148 | printk(KERN_NOTICE "kAFS: %s: Invalid argument: %s\n", | ||
149 | option, *_value); | ||
150 | return 0; | ||
151 | } | ||
152 | return 1; | ||
153 | } /* end want_no_value() */ | ||
154 | |||
155 | /*****************************************************************************/ | ||
156 | /* | ||
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 | ||
160 | */ | ||
161 | static int afs_super_parse_options(struct afs_mount_params *params, | ||
162 | char *options, | ||
163 | const char **devname) | ||
164 | { | ||
165 | char *key, *value; | ||
166 | int ret; | ||
167 | |||
168 | _enter("%s", options); | ||
169 | |||
170 | options[PAGE_SIZE - 1] = 0; | ||
171 | |||
172 | ret = 0; | ||
173 | while ((key = strsep(&options, ",")) != 0) | ||
174 | { | ||
175 | value = strchr(key, '='); | ||
176 | if (value) | ||
177 | *value++ = 0; | ||
178 | |||
179 | printk("kAFS: KEY: %s, VAL:%s\n", key, value ?: "-"); | ||
180 | |||
181 | if (strcmp(key, "rwpath") == 0) { | ||
182 | if (!want_no_value(&value, "rwpath")) | ||
183 | return -EINVAL; | ||
184 | params->rwpath = 1; | ||
185 | continue; | ||
186 | } | ||
187 | else if (strcmp(key, "vol") == 0) { | ||
188 | if (!want_arg(&value, "vol")) | ||
189 | return -EINVAL; | ||
190 | *devname = value; | ||
191 | continue; | ||
192 | } | ||
193 | else if (strcmp(key, "cell") == 0) { | ||
194 | if (!want_arg(&value, "cell")) | ||
195 | return -EINVAL; | ||
196 | afs_put_cell(params->default_cell); | ||
197 | ret = afs_cell_lookup(value, | ||
198 | strlen(value), | ||
199 | ¶ms->default_cell); | ||
200 | if (ret < 0) | ||
201 | return -EINVAL; | ||
202 | continue; | ||
203 | } | ||
204 | |||
205 | printk("kAFS: Unknown mount option: '%s'\n", key); | ||
206 | ret = -EINVAL; | ||
207 | goto error; | ||
208 | } | ||
209 | |||
210 | ret = 0; | ||
211 | |||
212 | error: | ||
213 | _leave(" = %d", ret); | ||
214 | return ret; | ||
215 | } /* end afs_super_parse_options() */ | ||
216 | |||
217 | /*****************************************************************************/ | ||
218 | /* | ||
219 | * check a superblock to see if it's the one we're looking for | ||
220 | */ | ||
221 | static int afs_test_super(struct super_block *sb, void *data) | ||
222 | { | ||
223 | struct afs_mount_params *params = data; | ||
224 | struct afs_super_info *as = sb->s_fs_info; | ||
225 | |||
226 | return as->volume == params->volume; | ||
227 | } /* end afs_test_super() */ | ||
228 | |||
229 | /*****************************************************************************/ | ||
230 | /* | ||
231 | * fill in the superblock | ||
232 | */ | ||
233 | static int afs_fill_super(struct super_block *sb, void *data, int silent) | ||
234 | { | ||
235 | struct afs_mount_params *params = data; | ||
236 | struct afs_super_info *as = NULL; | ||
237 | struct afs_fid fid; | ||
238 | struct dentry *root = NULL; | ||
239 | struct inode *inode = NULL; | ||
240 | int ret; | ||
241 | |||
242 | kenter(""); | ||
243 | |||
244 | /* allocate a superblock info record */ | ||
245 | as = kmalloc(sizeof(struct afs_super_info), GFP_KERNEL); | ||
246 | if (!as) { | ||
247 | _leave(" = -ENOMEM"); | ||
248 | return -ENOMEM; | ||
249 | } | ||
250 | |||
251 | memset(as, 0, sizeof(struct afs_super_info)); | ||
252 | |||
253 | afs_get_volume(params->volume); | ||
254 | as->volume = params->volume; | ||
255 | |||
256 | /* fill in the superblock */ | ||
257 | sb->s_blocksize = PAGE_CACHE_SIZE; | ||
258 | sb->s_blocksize_bits = PAGE_CACHE_SHIFT; | ||
259 | sb->s_magic = AFS_FS_MAGIC; | ||
260 | sb->s_op = &afs_super_ops; | ||
261 | sb->s_fs_info = as; | ||
262 | |||
263 | /* allocate the root inode and dentry */ | ||
264 | fid.vid = as->volume->vid; | ||
265 | fid.vnode = 1; | ||
266 | fid.unique = 1; | ||
267 | ret = afs_iget(sb, &fid, &inode); | ||
268 | if (ret < 0) | ||
269 | goto error; | ||
270 | |||
271 | ret = -ENOMEM; | ||
272 | root = d_alloc_root(inode); | ||
273 | if (!root) | ||
274 | goto error; | ||
275 | |||
276 | sb->s_root = root; | ||
277 | |||
278 | kleave(" = 0"); | ||
279 | return 0; | ||
280 | |||
281 | error: | ||
282 | iput(inode); | ||
283 | afs_put_volume(as->volume); | ||
284 | kfree(as); | ||
285 | |||
286 | sb->s_fs_info = NULL; | ||
287 | |||
288 | kleave(" = %d", ret); | ||
289 | return ret; | ||
290 | } /* end afs_fill_super() */ | ||
291 | |||
292 | /*****************************************************************************/ | ||
293 | /* | ||
294 | * get an AFS superblock | ||
295 | * - TODO: don't use get_sb_nodev(), but rather call sget() directly | ||
296 | */ | ||
297 | static struct super_block *afs_get_sb(struct file_system_type *fs_type, | ||
298 | int flags, | ||
299 | const char *dev_name, | ||
300 | void *options) | ||
301 | { | ||
302 | struct afs_mount_params params; | ||
303 | struct super_block *sb; | ||
304 | int ret; | ||
305 | |||
306 | _enter(",,%s,%p", dev_name, options); | ||
307 | |||
308 | memset(¶ms, 0, sizeof(params)); | ||
309 | |||
310 | /* start the cache manager */ | ||
311 | ret = afscm_start(); | ||
312 | if (ret < 0) { | ||
313 | _leave(" = %d", ret); | ||
314 | return ERR_PTR(ret); | ||
315 | } | ||
316 | |||
317 | /* parse the options */ | ||
318 | if (options) { | ||
319 | ret = afs_super_parse_options(¶ms, options, &dev_name); | ||
320 | if (ret < 0) | ||
321 | goto error; | ||
322 | if (!dev_name) { | ||
323 | printk("kAFS: no volume name specified\n"); | ||
324 | ret = -EINVAL; | ||
325 | goto error; | ||
326 | } | ||
327 | } | ||
328 | |||
329 | /* parse the device name */ | ||
330 | ret = afs_volume_lookup(dev_name, | ||
331 | params.default_cell, | ||
332 | params.rwpath, | ||
333 | ¶ms.volume); | ||
334 | if (ret < 0) | ||
335 | goto error; | ||
336 | |||
337 | /* allocate a deviceless superblock */ | ||
338 | sb = sget(fs_type, afs_test_super, set_anon_super, ¶ms); | ||
339 | if (IS_ERR(sb)) | ||
340 | goto error; | ||
341 | |||
342 | sb->s_flags = flags; | ||
343 | |||
344 | ret = afs_fill_super(sb, ¶ms, flags & MS_VERBOSE ? 1 : 0); | ||
345 | if (ret < 0) { | ||
346 | up_write(&sb->s_umount); | ||
347 | deactivate_super(sb); | ||
348 | goto error; | ||
349 | } | ||
350 | sb->s_flags |= MS_ACTIVE; | ||
351 | |||
352 | afs_put_volume(params.volume); | ||
353 | afs_put_cell(params.default_cell); | ||
354 | _leave(" = %p", sb); | ||
355 | return sb; | ||
356 | |||
357 | error: | ||
358 | afs_put_volume(params.volume); | ||
359 | afs_put_cell(params.default_cell); | ||
360 | afscm_stop(); | ||
361 | _leave(" = %d", ret); | ||
362 | return ERR_PTR(ret); | ||
363 | } /* end afs_get_sb() */ | ||
364 | |||
365 | /*****************************************************************************/ | ||
366 | /* | ||
367 | * finish the unmounting process on the superblock | ||
368 | */ | ||
369 | static void afs_put_super(struct super_block *sb) | ||
370 | { | ||
371 | struct afs_super_info *as = sb->s_fs_info; | ||
372 | |||
373 | _enter(""); | ||
374 | |||
375 | afs_put_volume(as->volume); | ||
376 | afscm_stop(); | ||
377 | |||
378 | _leave(""); | ||
379 | } /* end afs_put_super() */ | ||
380 | |||
381 | /*****************************************************************************/ | ||
382 | /* | ||
383 | * initialise an inode cache slab element prior to any use | ||
384 | */ | ||
385 | static void afs_i_init_once(void *_vnode, kmem_cache_t *cachep, | ||
386 | unsigned long flags) | ||
387 | { | ||
388 | struct afs_vnode *vnode = (struct afs_vnode *) _vnode; | ||
389 | |||
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); | ||
400 | } | ||
401 | |||
402 | } /* end afs_i_init_once() */ | ||
403 | |||
404 | /*****************************************************************************/ | ||
405 | /* | ||
406 | * allocate an AFS inode struct from our slab cache | ||
407 | */ | ||
408 | static struct inode *afs_alloc_inode(struct super_block *sb) | ||
409 | { | ||
410 | struct afs_vnode *vnode; | ||
411 | |||
412 | vnode = (struct afs_vnode *) | ||
413 | kmem_cache_alloc(afs_inode_cachep, SLAB_KERNEL); | ||
414 | if (!vnode) | ||
415 | return NULL; | ||
416 | |||
417 | atomic_inc(&afs_count_active_inodes); | ||
418 | |||
419 | memset(&vnode->fid, 0, sizeof(vnode->fid)); | ||
420 | memset(&vnode->status, 0, sizeof(vnode->status)); | ||
421 | |||
422 | vnode->volume = NULL; | ||
423 | vnode->update_cnt = 0; | ||
424 | vnode->flags = 0; | ||
425 | |||
426 | return &vnode->vfs_inode; | ||
427 | } /* end afs_alloc_inode() */ | ||
428 | |||
429 | /*****************************************************************************/ | ||
430 | /* | ||
431 | * destroy an AFS inode struct | ||
432 | */ | ||
433 | static void afs_destroy_inode(struct inode *inode) | ||
434 | { | ||
435 | _enter("{%lu}", inode->i_ino); | ||
436 | |||
437 | kmem_cache_free(afs_inode_cachep, AFS_FS_I(inode)); | ||
438 | |||
439 | atomic_dec(&afs_count_active_inodes); | ||
440 | |||
441 | } /* end afs_destroy_inode() */ | ||