Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 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 | |
David Howells | 454e239 | 2006-06-23 02:02:57 -0700 | [diff] [blame] | 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); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 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 | */ |
David Howells | 454e239 | 2006-06-23 02:02:57 -0700 | [diff] [blame] | 297 | static int afs_get_sb(struct file_system_type *fs_type, |
| 298 | int flags, |
| 299 | const char *dev_name, |
| 300 | void *options, |
| 301 | struct vfsmount *mnt) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 302 | { |
| 303 | struct afs_mount_params params; |
| 304 | struct super_block *sb; |
| 305 | int ret; |
| 306 | |
| 307 | _enter(",,%s,%p", dev_name, options); |
| 308 | |
| 309 | memset(¶ms, 0, sizeof(params)); |
| 310 | |
| 311 | /* start the cache manager */ |
| 312 | ret = afscm_start(); |
| 313 | if (ret < 0) { |
| 314 | _leave(" = %d", ret); |
David Howells | 454e239 | 2006-06-23 02:02:57 -0700 | [diff] [blame] | 315 | return ret; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 316 | } |
| 317 | |
| 318 | /* parse the options */ |
| 319 | if (options) { |
| 320 | ret = afs_super_parse_options(¶ms, options, &dev_name); |
| 321 | if (ret < 0) |
| 322 | goto error; |
| 323 | if (!dev_name) { |
| 324 | printk("kAFS: no volume name specified\n"); |
| 325 | ret = -EINVAL; |
| 326 | goto error; |
| 327 | } |
| 328 | } |
| 329 | |
| 330 | /* parse the device name */ |
| 331 | ret = afs_volume_lookup(dev_name, |
| 332 | params.default_cell, |
| 333 | params.rwpath, |
| 334 | ¶ms.volume); |
| 335 | if (ret < 0) |
| 336 | goto error; |
| 337 | |
| 338 | /* allocate a deviceless superblock */ |
| 339 | sb = sget(fs_type, afs_test_super, set_anon_super, ¶ms); |
| 340 | if (IS_ERR(sb)) |
| 341 | goto error; |
| 342 | |
| 343 | sb->s_flags = flags; |
| 344 | |
Theodore Ts'o | 9b04c99 | 2006-03-24 03:15:10 -0800 | [diff] [blame] | 345 | ret = afs_fill_super(sb, ¶ms, flags & MS_SILENT ? 1 : 0); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 346 | if (ret < 0) { |
| 347 | up_write(&sb->s_umount); |
| 348 | deactivate_super(sb); |
| 349 | goto error; |
| 350 | } |
| 351 | sb->s_flags |= MS_ACTIVE; |
David Howells | 454e239 | 2006-06-23 02:02:57 -0700 | [diff] [blame] | 352 | simple_set_mnt(mnt, sb); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 353 | |
| 354 | afs_put_volume(params.volume); |
| 355 | afs_put_cell(params.default_cell); |
David Howells | 454e239 | 2006-06-23 02:02:57 -0700 | [diff] [blame] | 356 | _leave(" = 0 [%p]", 0, sb); |
| 357 | return 0; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 358 | |
| 359 | error: |
| 360 | afs_put_volume(params.volume); |
| 361 | afs_put_cell(params.default_cell); |
| 362 | afscm_stop(); |
| 363 | _leave(" = %d", ret); |
David Howells | 454e239 | 2006-06-23 02:02:57 -0700 | [diff] [blame] | 364 | return ret; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 365 | } /* end afs_get_sb() */ |
| 366 | |
| 367 | /*****************************************************************************/ |
| 368 | /* |
| 369 | * finish the unmounting process on the superblock |
| 370 | */ |
| 371 | static void afs_put_super(struct super_block *sb) |
| 372 | { |
| 373 | struct afs_super_info *as = sb->s_fs_info; |
| 374 | |
| 375 | _enter(""); |
| 376 | |
| 377 | afs_put_volume(as->volume); |
| 378 | afscm_stop(); |
| 379 | |
| 380 | _leave(""); |
| 381 | } /* end afs_put_super() */ |
| 382 | |
| 383 | /*****************************************************************************/ |
| 384 | /* |
| 385 | * initialise an inode cache slab element prior to any use |
| 386 | */ |
| 387 | static void afs_i_init_once(void *_vnode, kmem_cache_t *cachep, |
| 388 | unsigned long flags) |
| 389 | { |
| 390 | struct afs_vnode *vnode = (struct afs_vnode *) _vnode; |
| 391 | |
| 392 | if ((flags & (SLAB_CTOR_VERIFY|SLAB_CTOR_CONSTRUCTOR)) == |
| 393 | SLAB_CTOR_CONSTRUCTOR) { |
| 394 | memset(vnode, 0, sizeof(*vnode)); |
| 395 | inode_init_once(&vnode->vfs_inode); |
| 396 | init_waitqueue_head(&vnode->update_waitq); |
| 397 | spin_lock_init(&vnode->lock); |
| 398 | INIT_LIST_HEAD(&vnode->cb_link); |
| 399 | INIT_LIST_HEAD(&vnode->cb_hash_link); |
| 400 | afs_timer_init(&vnode->cb_timeout, |
| 401 | &afs_vnode_cb_timed_out_ops); |
| 402 | } |
| 403 | |
| 404 | } /* end afs_i_init_once() */ |
| 405 | |
| 406 | /*****************************************************************************/ |
| 407 | /* |
| 408 | * allocate an AFS inode struct from our slab cache |
| 409 | */ |
| 410 | static struct inode *afs_alloc_inode(struct super_block *sb) |
| 411 | { |
| 412 | struct afs_vnode *vnode; |
| 413 | |
| 414 | vnode = (struct afs_vnode *) |
| 415 | kmem_cache_alloc(afs_inode_cachep, SLAB_KERNEL); |
| 416 | if (!vnode) |
| 417 | return NULL; |
| 418 | |
| 419 | atomic_inc(&afs_count_active_inodes); |
| 420 | |
| 421 | memset(&vnode->fid, 0, sizeof(vnode->fid)); |
| 422 | memset(&vnode->status, 0, sizeof(vnode->status)); |
| 423 | |
| 424 | vnode->volume = NULL; |
| 425 | vnode->update_cnt = 0; |
| 426 | vnode->flags = 0; |
| 427 | |
| 428 | return &vnode->vfs_inode; |
| 429 | } /* end afs_alloc_inode() */ |
| 430 | |
| 431 | /*****************************************************************************/ |
| 432 | /* |
| 433 | * destroy an AFS inode struct |
| 434 | */ |
| 435 | static void afs_destroy_inode(struct inode *inode) |
| 436 | { |
| 437 | _enter("{%lu}", inode->i_ino); |
| 438 | |
| 439 | kmem_cache_free(afs_inode_cachep, AFS_FS_I(inode)); |
| 440 | |
| 441 | atomic_dec(&afs_count_active_inodes); |
| 442 | |
| 443 | } /* end afs_destroy_inode() */ |