Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1 | /* |
| 2 | * dir.c - Operations for sysfs directories. |
| 3 | */ |
| 4 | |
| 5 | #undef DEBUG |
| 6 | |
| 7 | #include <linux/fs.h> |
| 8 | #include <linux/mount.h> |
| 9 | #include <linux/module.h> |
| 10 | #include <linux/kobject.h> |
Christoph Hellwig | 5f45f1a | 2005-06-23 00:09:12 -0700 | [diff] [blame] | 11 | #include <linux/namei.h> |
Tejun Heo | 2b611bb | 2007-06-14 03:45:13 +0900 | [diff] [blame] | 12 | #include <linux/idr.h> |
Tejun Heo | 8619f97 | 2007-06-14 03:45:18 +0900 | [diff] [blame] | 13 | #include <linux/completion.h> |
Dave Young | 869512a | 2007-07-26 14:53:53 +0000 | [diff] [blame] | 14 | #include <linux/mutex.h> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 15 | #include "sysfs.h" |
| 16 | |
Tejun Heo | 3007e99 | 2007-06-14 04:27:23 +0900 | [diff] [blame] | 17 | DEFINE_MUTEX(sysfs_mutex); |
Tejun Heo | 5f99532 | 2007-06-14 04:27:23 +0900 | [diff] [blame] | 18 | spinlock_t sysfs_assoc_lock = SPIN_LOCK_UNLOCKED; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 19 | |
Tejun Heo | 2b611bb | 2007-06-14 03:45:13 +0900 | [diff] [blame] | 20 | static spinlock_t sysfs_ino_lock = SPIN_LOCK_UNLOCKED; |
| 21 | static DEFINE_IDA(sysfs_ino_ida); |
| 22 | |
Tejun Heo | b6b4a43 | 2007-06-14 03:45:18 +0900 | [diff] [blame] | 23 | /** |
Tejun Heo | 0c73f18 | 2007-06-14 03:45:18 +0900 | [diff] [blame] | 24 | * sysfs_link_sibling - link sysfs_dirent into sibling list |
| 25 | * @sd: sysfs_dirent of interest |
| 26 | * |
| 27 | * Link @sd into its sibling list which starts from |
| 28 | * sd->s_parent->s_children. |
| 29 | * |
| 30 | * Locking: |
Tejun Heo | 3007e99 | 2007-06-14 04:27:23 +0900 | [diff] [blame] | 31 | * mutex_lock(sysfs_mutex) |
Tejun Heo | 0c73f18 | 2007-06-14 03:45:18 +0900 | [diff] [blame] | 32 | */ |
Tejun Heo | 41fc1c2 | 2007-08-02 21:38:03 +0900 | [diff] [blame] | 33 | static void sysfs_link_sibling(struct sysfs_dirent *sd) |
Tejun Heo | 0c73f18 | 2007-06-14 03:45:18 +0900 | [diff] [blame] | 34 | { |
| 35 | struct sysfs_dirent *parent_sd = sd->s_parent; |
Eric W. Biederman | 3efa65b | 2007-08-20 21:36:30 +0900 | [diff] [blame^] | 36 | struct sysfs_dirent **pos; |
Tejun Heo | 0c73f18 | 2007-06-14 03:45:18 +0900 | [diff] [blame] | 37 | |
| 38 | BUG_ON(sd->s_sibling); |
Eric W. Biederman | 3efa65b | 2007-08-20 21:36:30 +0900 | [diff] [blame^] | 39 | |
| 40 | /* Store directory entries in order by ino. This allows |
| 41 | * readdir to properly restart without having to add a |
| 42 | * cursor into the s_children list. |
| 43 | */ |
| 44 | for (pos = &parent_sd->s_children; *pos; pos = &(*pos)->s_sibling) { |
| 45 | if (sd->s_ino < (*pos)->s_ino) |
| 46 | break; |
| 47 | } |
| 48 | sd->s_sibling = *pos; |
| 49 | *pos = sd; |
Tejun Heo | 0c73f18 | 2007-06-14 03:45:18 +0900 | [diff] [blame] | 50 | } |
| 51 | |
| 52 | /** |
| 53 | * sysfs_unlink_sibling - unlink sysfs_dirent from sibling list |
| 54 | * @sd: sysfs_dirent of interest |
| 55 | * |
| 56 | * Unlink @sd from its sibling list which starts from |
| 57 | * sd->s_parent->s_children. |
| 58 | * |
| 59 | * Locking: |
Tejun Heo | 3007e99 | 2007-06-14 04:27:23 +0900 | [diff] [blame] | 60 | * mutex_lock(sysfs_mutex) |
Tejun Heo | 0c73f18 | 2007-06-14 03:45:18 +0900 | [diff] [blame] | 61 | */ |
Tejun Heo | 41fc1c2 | 2007-08-02 21:38:03 +0900 | [diff] [blame] | 62 | static void sysfs_unlink_sibling(struct sysfs_dirent *sd) |
Tejun Heo | 0c73f18 | 2007-06-14 03:45:18 +0900 | [diff] [blame] | 63 | { |
| 64 | struct sysfs_dirent **pos; |
| 65 | |
| 66 | for (pos = &sd->s_parent->s_children; *pos; pos = &(*pos)->s_sibling) { |
| 67 | if (*pos == sd) { |
| 68 | *pos = sd->s_sibling; |
| 69 | sd->s_sibling = NULL; |
| 70 | break; |
| 71 | } |
| 72 | } |
| 73 | } |
| 74 | |
| 75 | /** |
Tejun Heo | 53e0ae9 | 2007-06-14 04:27:25 +0900 | [diff] [blame] | 76 | * sysfs_get_dentry - get dentry for the given sysfs_dirent |
| 77 | * @sd: sysfs_dirent of interest |
| 78 | * |
| 79 | * Get dentry for @sd. Dentry is looked up if currently not |
| 80 | * present. This function climbs sysfs_dirent tree till it |
| 81 | * reaches a sysfs_dirent with valid dentry attached and descends |
| 82 | * down from there looking up dentry for each step. |
| 83 | * |
| 84 | * LOCKING: |
| 85 | * Kernel thread context (may sleep) |
| 86 | * |
| 87 | * RETURNS: |
| 88 | * Pointer to found dentry on success, ERR_PTR() value on error. |
| 89 | */ |
| 90 | struct dentry *sysfs_get_dentry(struct sysfs_dirent *sd) |
| 91 | { |
| 92 | struct sysfs_dirent *cur; |
| 93 | struct dentry *parent_dentry, *dentry; |
| 94 | int i, depth; |
| 95 | |
| 96 | /* Find the first parent which has valid s_dentry and get the |
| 97 | * dentry. |
| 98 | */ |
| 99 | mutex_lock(&sysfs_mutex); |
| 100 | restart0: |
| 101 | spin_lock(&sysfs_assoc_lock); |
| 102 | restart1: |
| 103 | spin_lock(&dcache_lock); |
| 104 | |
| 105 | dentry = NULL; |
| 106 | depth = 0; |
| 107 | cur = sd; |
| 108 | while (!cur->s_dentry || !cur->s_dentry->d_inode) { |
| 109 | if (cur->s_flags & SYSFS_FLAG_REMOVED) { |
| 110 | dentry = ERR_PTR(-ENOENT); |
| 111 | depth = 0; |
| 112 | break; |
| 113 | } |
| 114 | cur = cur->s_parent; |
| 115 | depth++; |
| 116 | } |
| 117 | if (!IS_ERR(dentry)) |
| 118 | dentry = dget_locked(cur->s_dentry); |
| 119 | |
| 120 | spin_unlock(&dcache_lock); |
| 121 | spin_unlock(&sysfs_assoc_lock); |
| 122 | |
| 123 | /* from the found dentry, look up depth times */ |
| 124 | while (depth--) { |
| 125 | /* find and get depth'th ancestor */ |
| 126 | for (cur = sd, i = 0; cur && i < depth; i++) |
| 127 | cur = cur->s_parent; |
| 128 | |
| 129 | /* This can happen if tree structure was modified due |
| 130 | * to move/rename. Restart. |
| 131 | */ |
| 132 | if (i != depth) { |
| 133 | dput(dentry); |
| 134 | goto restart0; |
| 135 | } |
| 136 | |
| 137 | sysfs_get(cur); |
| 138 | |
| 139 | mutex_unlock(&sysfs_mutex); |
| 140 | |
| 141 | /* look it up */ |
| 142 | parent_dentry = dentry; |
Tejun Heo | 2532802 | 2007-08-20 21:36:29 +0900 | [diff] [blame] | 143 | mutex_lock(&parent_dentry->d_inode->i_mutex); |
Tejun Heo | 53e0ae9 | 2007-06-14 04:27:25 +0900 | [diff] [blame] | 144 | dentry = lookup_one_len_kern(cur->s_name, parent_dentry, |
| 145 | strlen(cur->s_name)); |
Tejun Heo | 2532802 | 2007-08-20 21:36:29 +0900 | [diff] [blame] | 146 | mutex_unlock(&parent_dentry->d_inode->i_mutex); |
Tejun Heo | 53e0ae9 | 2007-06-14 04:27:25 +0900 | [diff] [blame] | 147 | dput(parent_dentry); |
| 148 | |
| 149 | if (IS_ERR(dentry)) { |
| 150 | sysfs_put(cur); |
| 151 | return dentry; |
| 152 | } |
| 153 | |
| 154 | mutex_lock(&sysfs_mutex); |
| 155 | spin_lock(&sysfs_assoc_lock); |
| 156 | |
| 157 | /* This, again, can happen if tree structure has |
| 158 | * changed and we looked up the wrong thing. Restart. |
| 159 | */ |
| 160 | if (cur->s_dentry != dentry) { |
| 161 | dput(dentry); |
| 162 | sysfs_put(cur); |
| 163 | goto restart1; |
| 164 | } |
| 165 | |
| 166 | spin_unlock(&sysfs_assoc_lock); |
| 167 | |
| 168 | sysfs_put(cur); |
| 169 | } |
| 170 | |
| 171 | mutex_unlock(&sysfs_mutex); |
| 172 | return dentry; |
| 173 | } |
| 174 | |
| 175 | /** |
Tejun Heo | b6b4a43 | 2007-06-14 03:45:18 +0900 | [diff] [blame] | 176 | * sysfs_get_active - get an active reference to sysfs_dirent |
| 177 | * @sd: sysfs_dirent to get an active reference to |
| 178 | * |
| 179 | * Get an active reference of @sd. This function is noop if @sd |
| 180 | * is NULL. |
| 181 | * |
| 182 | * RETURNS: |
| 183 | * Pointer to @sd on success, NULL on failure. |
| 184 | */ |
| 185 | struct sysfs_dirent *sysfs_get_active(struct sysfs_dirent *sd) |
| 186 | { |
Tejun Heo | 8619f97 | 2007-06-14 03:45:18 +0900 | [diff] [blame] | 187 | if (unlikely(!sd)) |
| 188 | return NULL; |
| 189 | |
| 190 | while (1) { |
| 191 | int v, t; |
| 192 | |
| 193 | v = atomic_read(&sd->s_active); |
| 194 | if (unlikely(v < 0)) |
| 195 | return NULL; |
| 196 | |
| 197 | t = atomic_cmpxchg(&sd->s_active, v, v + 1); |
| 198 | if (likely(t == v)) |
| 199 | return sd; |
| 200 | if (t < 0) |
| 201 | return NULL; |
| 202 | |
| 203 | cpu_relax(); |
Tejun Heo | b6b4a43 | 2007-06-14 03:45:18 +0900 | [diff] [blame] | 204 | } |
Tejun Heo | b6b4a43 | 2007-06-14 03:45:18 +0900 | [diff] [blame] | 205 | } |
| 206 | |
| 207 | /** |
| 208 | * sysfs_put_active - put an active reference to sysfs_dirent |
| 209 | * @sd: sysfs_dirent to put an active reference to |
| 210 | * |
| 211 | * Put an active reference to @sd. This function is noop if @sd |
| 212 | * is NULL. |
| 213 | */ |
| 214 | void sysfs_put_active(struct sysfs_dirent *sd) |
| 215 | { |
Tejun Heo | 8619f97 | 2007-06-14 03:45:18 +0900 | [diff] [blame] | 216 | struct completion *cmpl; |
| 217 | int v; |
| 218 | |
| 219 | if (unlikely(!sd)) |
| 220 | return; |
| 221 | |
| 222 | v = atomic_dec_return(&sd->s_active); |
| 223 | if (likely(v != SD_DEACTIVATED_BIAS)) |
| 224 | return; |
| 225 | |
| 226 | /* atomic_dec_return() is a mb(), we'll always see the updated |
Tejun Heo | 0c73f18 | 2007-06-14 03:45:18 +0900 | [diff] [blame] | 227 | * sd->s_sibling. |
Tejun Heo | 8619f97 | 2007-06-14 03:45:18 +0900 | [diff] [blame] | 228 | */ |
Tejun Heo | 0c73f18 | 2007-06-14 03:45:18 +0900 | [diff] [blame] | 229 | cmpl = (void *)sd->s_sibling; |
Tejun Heo | 8619f97 | 2007-06-14 03:45:18 +0900 | [diff] [blame] | 230 | complete(cmpl); |
Tejun Heo | b6b4a43 | 2007-06-14 03:45:18 +0900 | [diff] [blame] | 231 | } |
| 232 | |
| 233 | /** |
| 234 | * sysfs_get_active_two - get active references to sysfs_dirent and parent |
| 235 | * @sd: sysfs_dirent of interest |
| 236 | * |
| 237 | * Get active reference to @sd and its parent. Parent's active |
| 238 | * reference is grabbed first. This function is noop if @sd is |
| 239 | * NULL. |
| 240 | * |
| 241 | * RETURNS: |
| 242 | * Pointer to @sd on success, NULL on failure. |
| 243 | */ |
| 244 | struct sysfs_dirent *sysfs_get_active_two(struct sysfs_dirent *sd) |
| 245 | { |
| 246 | if (sd) { |
| 247 | if (sd->s_parent && unlikely(!sysfs_get_active(sd->s_parent))) |
| 248 | return NULL; |
| 249 | if (unlikely(!sysfs_get_active(sd))) { |
| 250 | sysfs_put_active(sd->s_parent); |
| 251 | return NULL; |
| 252 | } |
| 253 | } |
| 254 | return sd; |
| 255 | } |
| 256 | |
| 257 | /** |
| 258 | * sysfs_put_active_two - put active references to sysfs_dirent and parent |
| 259 | * @sd: sysfs_dirent of interest |
| 260 | * |
| 261 | * Put active references to @sd and its parent. This function is |
| 262 | * noop if @sd is NULL. |
| 263 | */ |
| 264 | void sysfs_put_active_two(struct sysfs_dirent *sd) |
| 265 | { |
| 266 | if (sd) { |
| 267 | sysfs_put_active(sd); |
| 268 | sysfs_put_active(sd->s_parent); |
| 269 | } |
| 270 | } |
| 271 | |
| 272 | /** |
| 273 | * sysfs_deactivate - deactivate sysfs_dirent |
| 274 | * @sd: sysfs_dirent to deactivate |
| 275 | * |
Tejun Heo | 8619f97 | 2007-06-14 03:45:18 +0900 | [diff] [blame] | 276 | * Deny new active references and drain existing ones. |
Tejun Heo | b6b4a43 | 2007-06-14 03:45:18 +0900 | [diff] [blame] | 277 | */ |
Tejun Heo | fb6896d | 2007-06-14 04:27:24 +0900 | [diff] [blame] | 278 | static void sysfs_deactivate(struct sysfs_dirent *sd) |
Tejun Heo | b6b4a43 | 2007-06-14 03:45:18 +0900 | [diff] [blame] | 279 | { |
Tejun Heo | 8619f97 | 2007-06-14 03:45:18 +0900 | [diff] [blame] | 280 | DECLARE_COMPLETION_ONSTACK(wait); |
| 281 | int v; |
Tejun Heo | b6b4a43 | 2007-06-14 03:45:18 +0900 | [diff] [blame] | 282 | |
Tejun Heo | 380e6fb | 2007-06-14 04:27:22 +0900 | [diff] [blame] | 283 | BUG_ON(sd->s_sibling || !(sd->s_flags & SYSFS_FLAG_REMOVED)); |
Tejun Heo | 0c73f18 | 2007-06-14 03:45:18 +0900 | [diff] [blame] | 284 | sd->s_sibling = (void *)&wait; |
Tejun Heo | 8619f97 | 2007-06-14 03:45:18 +0900 | [diff] [blame] | 285 | |
| 286 | /* atomic_add_return() is a mb(), put_active() will always see |
Tejun Heo | 0c73f18 | 2007-06-14 03:45:18 +0900 | [diff] [blame] | 287 | * the updated sd->s_sibling. |
Tejun Heo | b6b4a43 | 2007-06-14 03:45:18 +0900 | [diff] [blame] | 288 | */ |
Tejun Heo | 8619f97 | 2007-06-14 03:45:18 +0900 | [diff] [blame] | 289 | v = atomic_add_return(SD_DEACTIVATED_BIAS, &sd->s_active); |
| 290 | |
| 291 | if (v != SD_DEACTIVATED_BIAS) |
| 292 | wait_for_completion(&wait); |
| 293 | |
Tejun Heo | 0c73f18 | 2007-06-14 03:45:18 +0900 | [diff] [blame] | 294 | sd->s_sibling = NULL; |
Tejun Heo | b6b4a43 | 2007-06-14 03:45:18 +0900 | [diff] [blame] | 295 | } |
| 296 | |
Tejun Heo | 42b37df | 2007-06-14 03:45:17 +0900 | [diff] [blame] | 297 | static int sysfs_alloc_ino(ino_t *pino) |
Tejun Heo | 2b611bb | 2007-06-14 03:45:13 +0900 | [diff] [blame] | 298 | { |
| 299 | int ino, rc; |
| 300 | |
| 301 | retry: |
| 302 | spin_lock(&sysfs_ino_lock); |
| 303 | rc = ida_get_new_above(&sysfs_ino_ida, 2, &ino); |
| 304 | spin_unlock(&sysfs_ino_lock); |
| 305 | |
| 306 | if (rc == -EAGAIN) { |
| 307 | if (ida_pre_get(&sysfs_ino_ida, GFP_KERNEL)) |
| 308 | goto retry; |
| 309 | rc = -ENOMEM; |
| 310 | } |
| 311 | |
| 312 | *pino = ino; |
| 313 | return rc; |
| 314 | } |
| 315 | |
| 316 | static void sysfs_free_ino(ino_t ino) |
| 317 | { |
| 318 | spin_lock(&sysfs_ino_lock); |
| 319 | ida_remove(&sysfs_ino_ida, ino); |
| 320 | spin_unlock(&sysfs_ino_lock); |
| 321 | } |
| 322 | |
Tejun Heo | fa7f912 | 2007-06-14 03:45:13 +0900 | [diff] [blame] | 323 | void release_sysfs_dirent(struct sysfs_dirent * sd) |
| 324 | { |
Tejun Heo | 13b3086 | 2007-06-14 03:45:14 +0900 | [diff] [blame] | 325 | struct sysfs_dirent *parent_sd; |
| 326 | |
| 327 | repeat: |
Tejun Heo | 3007e99 | 2007-06-14 04:27:23 +0900 | [diff] [blame] | 328 | /* Moving/renaming is always done while holding reference. |
| 329 | * sd->s_parent won't change beneath us. |
| 330 | */ |
Tejun Heo | 13b3086 | 2007-06-14 03:45:14 +0900 | [diff] [blame] | 331 | parent_sd = sd->s_parent; |
| 332 | |
Tejun Heo | b402d72 | 2007-06-14 04:27:21 +0900 | [diff] [blame] | 333 | if (sysfs_type(sd) == SYSFS_KOBJ_LINK) |
Tejun Heo | 2b29ac2 | 2007-06-14 03:45:15 +0900 | [diff] [blame] | 334 | sysfs_put(sd->s_elem.symlink.target_sd); |
Tejun Heo | b402d72 | 2007-06-14 04:27:21 +0900 | [diff] [blame] | 335 | if (sysfs_type(sd) & SYSFS_COPY_NAME) |
Tejun Heo | 0c096b5 | 2007-06-14 03:45:15 +0900 | [diff] [blame] | 336 | kfree(sd->s_name); |
Tejun Heo | fa7f912 | 2007-06-14 03:45:13 +0900 | [diff] [blame] | 337 | kfree(sd->s_iattr); |
Tejun Heo | 2b611bb | 2007-06-14 03:45:13 +0900 | [diff] [blame] | 338 | sysfs_free_ino(sd->s_ino); |
Tejun Heo | fa7f912 | 2007-06-14 03:45:13 +0900 | [diff] [blame] | 339 | kmem_cache_free(sysfs_dir_cachep, sd); |
Tejun Heo | 13b3086 | 2007-06-14 03:45:14 +0900 | [diff] [blame] | 340 | |
| 341 | sd = parent_sd; |
| 342 | if (sd && atomic_dec_and_test(&sd->s_count)) |
| 343 | goto repeat; |
Tejun Heo | fa7f912 | 2007-06-14 03:45:13 +0900 | [diff] [blame] | 344 | } |
| 345 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 346 | static void sysfs_d_iput(struct dentry * dentry, struct inode * inode) |
| 347 | { |
| 348 | struct sysfs_dirent * sd = dentry->d_fsdata; |
| 349 | |
| 350 | if (sd) { |
Tejun Heo | 5f99532 | 2007-06-14 04:27:23 +0900 | [diff] [blame] | 351 | /* sd->s_dentry is protected with sysfs_assoc_lock. |
| 352 | * This allows sysfs_drop_dentry() to dereference it. |
Tejun Heo | dd14cbc | 2007-06-11 14:04:01 +0900 | [diff] [blame] | 353 | */ |
Tejun Heo | 5f99532 | 2007-06-14 04:27:23 +0900 | [diff] [blame] | 354 | spin_lock(&sysfs_assoc_lock); |
Tejun Heo | dd14cbc | 2007-06-11 14:04:01 +0900 | [diff] [blame] | 355 | |
| 356 | /* The dentry might have been deleted or another |
| 357 | * lookup could have happened updating sd->s_dentry to |
| 358 | * point the new dentry. Ignore if it isn't pointing |
| 359 | * to this dentry. |
| 360 | */ |
| 361 | if (sd->s_dentry == dentry) |
| 362 | sd->s_dentry = NULL; |
Tejun Heo | 5f99532 | 2007-06-14 04:27:23 +0900 | [diff] [blame] | 363 | spin_unlock(&sysfs_assoc_lock); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 364 | sysfs_put(sd); |
| 365 | } |
| 366 | iput(inode); |
| 367 | } |
| 368 | |
| 369 | static struct dentry_operations sysfs_dentry_ops = { |
| 370 | .d_iput = sysfs_d_iput, |
| 371 | }; |
| 372 | |
Tejun Heo | 3e51903 | 2007-06-14 03:45:15 +0900 | [diff] [blame] | 373 | struct sysfs_dirent *sysfs_new_dirent(const char *name, umode_t mode, int type) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 374 | { |
Tejun Heo | 0c096b5 | 2007-06-14 03:45:15 +0900 | [diff] [blame] | 375 | char *dup_name = NULL; |
Akinobu Mita | 01da242 | 2007-07-14 11:03:35 +0900 | [diff] [blame] | 376 | struct sysfs_dirent *sd; |
Tejun Heo | 0c096b5 | 2007-06-14 03:45:15 +0900 | [diff] [blame] | 377 | |
| 378 | if (type & SYSFS_COPY_NAME) { |
| 379 | name = dup_name = kstrdup(name, GFP_KERNEL); |
| 380 | if (!name) |
Akinobu Mita | 01da242 | 2007-07-14 11:03:35 +0900 | [diff] [blame] | 381 | return NULL; |
Tejun Heo | 0c096b5 | 2007-06-14 03:45:15 +0900 | [diff] [blame] | 382 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 383 | |
Robert P. J. Day | c376222 | 2007-02-10 01:45:03 -0800 | [diff] [blame] | 384 | sd = kmem_cache_zalloc(sysfs_dir_cachep, GFP_KERNEL); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 385 | if (!sd) |
Akinobu Mita | 01da242 | 2007-07-14 11:03:35 +0900 | [diff] [blame] | 386 | goto err_out1; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 387 | |
Tejun Heo | 0c096b5 | 2007-06-14 03:45:15 +0900 | [diff] [blame] | 388 | if (sysfs_alloc_ino(&sd->s_ino)) |
Akinobu Mita | 01da242 | 2007-07-14 11:03:35 +0900 | [diff] [blame] | 389 | goto err_out2; |
Tejun Heo | 2b611bb | 2007-06-14 03:45:13 +0900 | [diff] [blame] | 390 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 391 | atomic_set(&sd->s_count, 1); |
Tejun Heo | 8619f97 | 2007-06-14 03:45:18 +0900 | [diff] [blame] | 392 | atomic_set(&sd->s_active, 0); |
Juha Yrjölä | eea3f89 | 2006-08-03 19:06:25 +0300 | [diff] [blame] | 393 | atomic_set(&sd->s_event, 1); |
Tejun Heo | a26cd72 | 2007-06-14 03:45:14 +0900 | [diff] [blame] | 394 | |
Tejun Heo | 0c096b5 | 2007-06-14 03:45:15 +0900 | [diff] [blame] | 395 | sd->s_name = name; |
Tejun Heo | a26cd72 | 2007-06-14 03:45:14 +0900 | [diff] [blame] | 396 | sd->s_mode = mode; |
Tejun Heo | b402d72 | 2007-06-14 04:27:21 +0900 | [diff] [blame] | 397 | sd->s_flags = type; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 398 | |
| 399 | return sd; |
Tejun Heo | 0c096b5 | 2007-06-14 03:45:15 +0900 | [diff] [blame] | 400 | |
Akinobu Mita | 01da242 | 2007-07-14 11:03:35 +0900 | [diff] [blame] | 401 | err_out2: |
Tejun Heo | 0c096b5 | 2007-06-14 03:45:15 +0900 | [diff] [blame] | 402 | kmem_cache_free(sysfs_dir_cachep, sd); |
Akinobu Mita | 01da242 | 2007-07-14 11:03:35 +0900 | [diff] [blame] | 403 | err_out1: |
| 404 | kfree(dup_name); |
Tejun Heo | 0c096b5 | 2007-06-14 03:45:15 +0900 | [diff] [blame] | 405 | return NULL; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 406 | } |
| 407 | |
Tejun Heo | 3007e99 | 2007-06-14 04:27:23 +0900 | [diff] [blame] | 408 | /** |
| 409 | * sysfs_attach_dentry - associate sysfs_dirent with dentry |
| 410 | * @sd: target sysfs_dirent |
| 411 | * @dentry: dentry to associate |
| 412 | * |
| 413 | * Associate @sd with @dentry. This is protected by |
| 414 | * sysfs_assoc_lock to avoid race with sysfs_d_iput(). |
| 415 | * |
| 416 | * LOCKING: |
| 417 | * mutex_lock(sysfs_mutex) |
| 418 | */ |
Tejun Heo | 198a2a8 | 2007-06-14 03:45:16 +0900 | [diff] [blame] | 419 | static void sysfs_attach_dentry(struct sysfs_dirent *sd, struct dentry *dentry) |
| 420 | { |
| 421 | dentry->d_op = &sysfs_dentry_ops; |
| 422 | dentry->d_fsdata = sysfs_get(sd); |
| 423 | |
| 424 | /* protect sd->s_dentry against sysfs_d_iput */ |
Tejun Heo | 5f99532 | 2007-06-14 04:27:23 +0900 | [diff] [blame] | 425 | spin_lock(&sysfs_assoc_lock); |
Tejun Heo | 198a2a8 | 2007-06-14 03:45:16 +0900 | [diff] [blame] | 426 | sd->s_dentry = dentry; |
Tejun Heo | 5f99532 | 2007-06-14 04:27:23 +0900 | [diff] [blame] | 427 | spin_unlock(&sysfs_assoc_lock); |
Tejun Heo | 198a2a8 | 2007-06-14 03:45:16 +0900 | [diff] [blame] | 428 | |
| 429 | d_rehash(dentry); |
| 430 | } |
| 431 | |
Tejun Heo | fb6896d | 2007-06-14 04:27:24 +0900 | [diff] [blame] | 432 | static int sysfs_ilookup_test(struct inode *inode, void *arg) |
| 433 | { |
| 434 | struct sysfs_dirent *sd = arg; |
| 435 | return inode->i_ino == sd->s_ino; |
| 436 | } |
| 437 | |
Tejun Heo | 3007e99 | 2007-06-14 04:27:23 +0900 | [diff] [blame] | 438 | /** |
Tejun Heo | fb6896d | 2007-06-14 04:27:24 +0900 | [diff] [blame] | 439 | * sysfs_addrm_start - prepare for sysfs_dirent add/remove |
| 440 | * @acxt: pointer to sysfs_addrm_cxt to be used |
| 441 | * @parent_sd: parent sysfs_dirent |
Tejun Heo | 3007e99 | 2007-06-14 04:27:23 +0900 | [diff] [blame] | 442 | * |
Tejun Heo | fb6896d | 2007-06-14 04:27:24 +0900 | [diff] [blame] | 443 | * This function is called when the caller is about to add or |
| 444 | * remove sysfs_dirent under @parent_sd. This function acquires |
| 445 | * sysfs_mutex, grabs inode for @parent_sd if available and lock |
| 446 | * i_mutex of it. @acxt is used to keep and pass context to |
| 447 | * other addrm functions. |
Tejun Heo | 3007e99 | 2007-06-14 04:27:23 +0900 | [diff] [blame] | 448 | * |
| 449 | * LOCKING: |
Tejun Heo | fb6896d | 2007-06-14 04:27:24 +0900 | [diff] [blame] | 450 | * Kernel thread context (may sleep). sysfs_mutex is locked on |
| 451 | * return. i_mutex of parent inode is locked on return if |
| 452 | * available. |
Tejun Heo | 3007e99 | 2007-06-14 04:27:23 +0900 | [diff] [blame] | 453 | */ |
Tejun Heo | fb6896d | 2007-06-14 04:27:24 +0900 | [diff] [blame] | 454 | void sysfs_addrm_start(struct sysfs_addrm_cxt *acxt, |
| 455 | struct sysfs_dirent *parent_sd) |
Eric W. Biederman | b592fcf | 2007-01-24 12:35:52 -0700 | [diff] [blame] | 456 | { |
Tejun Heo | fb6896d | 2007-06-14 04:27:24 +0900 | [diff] [blame] | 457 | struct inode *inode; |
Tejun Heo | a26cd72 | 2007-06-14 03:45:14 +0900 | [diff] [blame] | 458 | |
Tejun Heo | fb6896d | 2007-06-14 04:27:24 +0900 | [diff] [blame] | 459 | memset(acxt, 0, sizeof(*acxt)); |
| 460 | acxt->parent_sd = parent_sd; |
| 461 | |
| 462 | /* Lookup parent inode. inode initialization and I_NEW |
| 463 | * clearing are protected by sysfs_mutex. By grabbing it and |
| 464 | * looking up with _nowait variant, inode state can be |
| 465 | * determined reliably. |
| 466 | */ |
| 467 | mutex_lock(&sysfs_mutex); |
| 468 | |
| 469 | inode = ilookup5_nowait(sysfs_sb, parent_sd->s_ino, sysfs_ilookup_test, |
| 470 | parent_sd); |
| 471 | |
| 472 | if (inode && !(inode->i_state & I_NEW)) { |
| 473 | /* parent inode available */ |
| 474 | acxt->parent_inode = inode; |
| 475 | |
| 476 | /* sysfs_mutex is below i_mutex in lock hierarchy. |
| 477 | * First, trylock i_mutex. If fails, unlock |
| 478 | * sysfs_mutex and lock them in order. |
| 479 | */ |
| 480 | if (!mutex_trylock(&inode->i_mutex)) { |
| 481 | mutex_unlock(&sysfs_mutex); |
| 482 | mutex_lock(&inode->i_mutex); |
| 483 | mutex_lock(&sysfs_mutex); |
| 484 | } |
| 485 | } else |
| 486 | iput(inode); |
| 487 | } |
| 488 | |
| 489 | /** |
| 490 | * sysfs_add_one - add sysfs_dirent to parent |
| 491 | * @acxt: addrm context to use |
| 492 | * @sd: sysfs_dirent to be added |
| 493 | * |
| 494 | * Get @acxt->parent_sd and set sd->s_parent to it and increment |
| 495 | * nlink of parent inode if @sd is a directory. @sd is NOT |
| 496 | * linked into the children list of the parent. The caller |
| 497 | * should invoke sysfs_link_sibling() after this function |
| 498 | * completes if @sd needs to be on the children list. |
| 499 | * |
| 500 | * This function should be called between calls to |
| 501 | * sysfs_addrm_start() and sysfs_addrm_finish() and should be |
| 502 | * passed the same @acxt as passed to sysfs_addrm_start(). |
| 503 | * |
| 504 | * LOCKING: |
| 505 | * Determined by sysfs_addrm_start(). |
Tejun Heo | 23dc279 | 2007-08-02 21:38:03 +0900 | [diff] [blame] | 506 | * |
| 507 | * RETURNS: |
| 508 | * 0 on success, -EEXIST if entry with the given name already |
| 509 | * exists. |
Tejun Heo | fb6896d | 2007-06-14 04:27:24 +0900 | [diff] [blame] | 510 | */ |
Tejun Heo | 23dc279 | 2007-08-02 21:38:03 +0900 | [diff] [blame] | 511 | int sysfs_add_one(struct sysfs_addrm_cxt *acxt, struct sysfs_dirent *sd) |
Tejun Heo | fb6896d | 2007-06-14 04:27:24 +0900 | [diff] [blame] | 512 | { |
Tejun Heo | 23dc279 | 2007-08-02 21:38:03 +0900 | [diff] [blame] | 513 | if (sysfs_find_dirent(acxt->parent_sd, sd->s_name)) |
| 514 | return -EEXIST; |
| 515 | |
Tejun Heo | fb6896d | 2007-06-14 04:27:24 +0900 | [diff] [blame] | 516 | sd->s_parent = sysfs_get(acxt->parent_sd); |
| 517 | |
| 518 | if (sysfs_type(sd) == SYSFS_DIR && acxt->parent_inode) |
| 519 | inc_nlink(acxt->parent_inode); |
| 520 | |
| 521 | acxt->cnt++; |
Tejun Heo | 41fc1c2 | 2007-08-02 21:38:03 +0900 | [diff] [blame] | 522 | |
| 523 | sysfs_link_sibling(sd); |
Tejun Heo | 23dc279 | 2007-08-02 21:38:03 +0900 | [diff] [blame] | 524 | |
| 525 | return 0; |
Tejun Heo | fb6896d | 2007-06-14 04:27:24 +0900 | [diff] [blame] | 526 | } |
| 527 | |
| 528 | /** |
| 529 | * sysfs_remove_one - remove sysfs_dirent from parent |
| 530 | * @acxt: addrm context to use |
| 531 | * @sd: sysfs_dirent to be added |
| 532 | * |
| 533 | * Mark @sd removed and drop nlink of parent inode if @sd is a |
| 534 | * directory. @sd is NOT unlinked from the children list of the |
| 535 | * parent. The caller is repsonsible for removing @sd from the |
| 536 | * children list before calling this function. |
| 537 | * |
| 538 | * This function should be called between calls to |
| 539 | * sysfs_addrm_start() and sysfs_addrm_finish() and should be |
| 540 | * passed the same @acxt as passed to sysfs_addrm_start(). |
| 541 | * |
| 542 | * LOCKING: |
| 543 | * Determined by sysfs_addrm_start(). |
| 544 | */ |
| 545 | void sysfs_remove_one(struct sysfs_addrm_cxt *acxt, struct sysfs_dirent *sd) |
| 546 | { |
Tejun Heo | 41fc1c2 | 2007-08-02 21:38:03 +0900 | [diff] [blame] | 547 | BUG_ON(sd->s_flags & SYSFS_FLAG_REMOVED); |
| 548 | |
| 549 | sysfs_unlink_sibling(sd); |
Tejun Heo | fb6896d | 2007-06-14 04:27:24 +0900 | [diff] [blame] | 550 | |
| 551 | sd->s_flags |= SYSFS_FLAG_REMOVED; |
| 552 | sd->s_sibling = acxt->removed; |
| 553 | acxt->removed = sd; |
| 554 | |
| 555 | if (sysfs_type(sd) == SYSFS_DIR && acxt->parent_inode) |
| 556 | drop_nlink(acxt->parent_inode); |
| 557 | |
| 558 | acxt->cnt++; |
| 559 | } |
| 560 | |
| 561 | /** |
Tejun Heo | a0edd7c | 2007-06-14 04:27:24 +0900 | [diff] [blame] | 562 | * sysfs_drop_dentry - drop dentry for the specified sysfs_dirent |
| 563 | * @sd: target sysfs_dirent |
| 564 | * |
| 565 | * Drop dentry for @sd. @sd must have been unlinked from its |
| 566 | * parent on entry to this function such that it can't be looked |
| 567 | * up anymore. |
| 568 | * |
| 569 | * @sd->s_dentry which is protected with sysfs_assoc_lock points |
| 570 | * to the currently associated dentry but we're not holding a |
| 571 | * reference to it and racing with dput(). Grab dcache_lock and |
| 572 | * verify dentry before dropping it. If @sd->s_dentry is NULL or |
| 573 | * dput() beats us, no need to bother. |
| 574 | */ |
| 575 | static void sysfs_drop_dentry(struct sysfs_dirent *sd) |
| 576 | { |
| 577 | struct dentry *dentry = NULL; |
| 578 | struct inode *inode; |
| 579 | |
| 580 | /* We're not holding a reference to ->s_dentry dentry but the |
| 581 | * field will stay valid as long as sysfs_assoc_lock is held. |
| 582 | */ |
| 583 | spin_lock(&sysfs_assoc_lock); |
| 584 | spin_lock(&dcache_lock); |
| 585 | |
| 586 | /* drop dentry if it's there and dput() didn't kill it yet */ |
| 587 | if (sd->s_dentry && sd->s_dentry->d_inode) { |
| 588 | dentry = dget_locked(sd->s_dentry); |
| 589 | spin_lock(&dentry->d_lock); |
| 590 | __d_drop(dentry); |
| 591 | spin_unlock(&dentry->d_lock); |
| 592 | } |
| 593 | |
| 594 | spin_unlock(&dcache_lock); |
| 595 | spin_unlock(&sysfs_assoc_lock); |
| 596 | |
Tejun Heo | 5122503 | 2007-06-14 04:27:25 +0900 | [diff] [blame] | 597 | dput(dentry); |
Tejun Heo | a0edd7c | 2007-06-14 04:27:24 +0900 | [diff] [blame] | 598 | |
| 599 | /* adjust nlink and update timestamp */ |
| 600 | inode = ilookup(sysfs_sb, sd->s_ino); |
| 601 | if (inode) { |
| 602 | mutex_lock(&inode->i_mutex); |
| 603 | |
| 604 | inode->i_ctime = CURRENT_TIME; |
| 605 | drop_nlink(inode); |
| 606 | if (sysfs_type(sd) == SYSFS_DIR) |
| 607 | drop_nlink(inode); |
| 608 | |
| 609 | mutex_unlock(&inode->i_mutex); |
| 610 | iput(inode); |
| 611 | } |
| 612 | } |
| 613 | |
| 614 | /** |
Tejun Heo | fb6896d | 2007-06-14 04:27:24 +0900 | [diff] [blame] | 615 | * sysfs_addrm_finish - finish up sysfs_dirent add/remove |
| 616 | * @acxt: addrm context to finish up |
| 617 | * |
| 618 | * Finish up sysfs_dirent add/remove. Resources acquired by |
| 619 | * sysfs_addrm_start() are released and removed sysfs_dirents are |
| 620 | * cleaned up. Timestamps on the parent inode are updated. |
| 621 | * |
| 622 | * LOCKING: |
| 623 | * All mutexes acquired by sysfs_addrm_start() are released. |
Tejun Heo | fb6896d | 2007-06-14 04:27:24 +0900 | [diff] [blame] | 624 | */ |
Tejun Heo | 990e53f | 2007-08-02 21:38:03 +0900 | [diff] [blame] | 625 | void sysfs_addrm_finish(struct sysfs_addrm_cxt *acxt) |
Tejun Heo | fb6896d | 2007-06-14 04:27:24 +0900 | [diff] [blame] | 626 | { |
| 627 | /* release resources acquired by sysfs_addrm_start() */ |
| 628 | mutex_unlock(&sysfs_mutex); |
| 629 | if (acxt->parent_inode) { |
| 630 | struct inode *inode = acxt->parent_inode; |
| 631 | |
| 632 | /* if added/removed, update timestamps on the parent */ |
| 633 | if (acxt->cnt) |
| 634 | inode->i_ctime = inode->i_mtime = CURRENT_TIME; |
| 635 | |
| 636 | mutex_unlock(&inode->i_mutex); |
| 637 | iput(inode); |
Tejun Heo | 13b3086 | 2007-06-14 03:45:14 +0900 | [diff] [blame] | 638 | } |
Tejun Heo | fb6896d | 2007-06-14 04:27:24 +0900 | [diff] [blame] | 639 | |
| 640 | /* kill removed sysfs_dirents */ |
| 641 | while (acxt->removed) { |
| 642 | struct sysfs_dirent *sd = acxt->removed; |
| 643 | |
| 644 | acxt->removed = sd->s_sibling; |
| 645 | sd->s_sibling = NULL; |
| 646 | |
| 647 | sysfs_drop_dentry(sd); |
| 648 | sysfs_deactivate(sd); |
| 649 | sysfs_put(sd); |
| 650 | } |
Eric W. Biederman | b592fcf | 2007-01-24 12:35:52 -0700 | [diff] [blame] | 651 | } |
| 652 | |
Tejun Heo | f0b0af4 | 2007-06-14 04:27:22 +0900 | [diff] [blame] | 653 | /** |
| 654 | * sysfs_find_dirent - find sysfs_dirent with the given name |
| 655 | * @parent_sd: sysfs_dirent to search under |
| 656 | * @name: name to look for |
Maneesh Soni | c516865 | 2006-03-09 19:40:14 +0530 | [diff] [blame] | 657 | * |
Tejun Heo | f0b0af4 | 2007-06-14 04:27:22 +0900 | [diff] [blame] | 658 | * Look for sysfs_dirent with name @name under @parent_sd. |
Maneesh Soni | c516865 | 2006-03-09 19:40:14 +0530 | [diff] [blame] | 659 | * |
Tejun Heo | f0b0af4 | 2007-06-14 04:27:22 +0900 | [diff] [blame] | 660 | * LOCKING: |
Tejun Heo | 3007e99 | 2007-06-14 04:27:23 +0900 | [diff] [blame] | 661 | * mutex_lock(sysfs_mutex) |
Tejun Heo | f0b0af4 | 2007-06-14 04:27:22 +0900 | [diff] [blame] | 662 | * |
| 663 | * RETURNS: |
| 664 | * Pointer to sysfs_dirent if found, NULL if not. |
Maneesh Soni | c516865 | 2006-03-09 19:40:14 +0530 | [diff] [blame] | 665 | */ |
Tejun Heo | f0b0af4 | 2007-06-14 04:27:22 +0900 | [diff] [blame] | 666 | struct sysfs_dirent *sysfs_find_dirent(struct sysfs_dirent *parent_sd, |
| 667 | const unsigned char *name) |
Maneesh Soni | c516865 | 2006-03-09 19:40:14 +0530 | [diff] [blame] | 668 | { |
Tejun Heo | f0b0af4 | 2007-06-14 04:27:22 +0900 | [diff] [blame] | 669 | struct sysfs_dirent *sd; |
Maneesh Soni | c516865 | 2006-03-09 19:40:14 +0530 | [diff] [blame] | 670 | |
Tejun Heo | f0b0af4 | 2007-06-14 04:27:22 +0900 | [diff] [blame] | 671 | for (sd = parent_sd->s_children; sd; sd = sd->s_sibling) |
Eric W. Biederman | 3efa65b | 2007-08-20 21:36:30 +0900 | [diff] [blame^] | 672 | if (!strcmp(sd->s_name, name)) |
Tejun Heo | f0b0af4 | 2007-06-14 04:27:22 +0900 | [diff] [blame] | 673 | return sd; |
| 674 | return NULL; |
| 675 | } |
Maneesh Soni | c516865 | 2006-03-09 19:40:14 +0530 | [diff] [blame] | 676 | |
Tejun Heo | f0b0af4 | 2007-06-14 04:27:22 +0900 | [diff] [blame] | 677 | /** |
| 678 | * sysfs_get_dirent - find and get sysfs_dirent with the given name |
| 679 | * @parent_sd: sysfs_dirent to search under |
| 680 | * @name: name to look for |
| 681 | * |
| 682 | * Look for sysfs_dirent with name @name under @parent_sd and get |
| 683 | * it if found. |
| 684 | * |
| 685 | * LOCKING: |
Tejun Heo | 3007e99 | 2007-06-14 04:27:23 +0900 | [diff] [blame] | 686 | * Kernel thread context (may sleep). Grabs sysfs_mutex. |
Tejun Heo | f0b0af4 | 2007-06-14 04:27:22 +0900 | [diff] [blame] | 687 | * |
| 688 | * RETURNS: |
| 689 | * Pointer to sysfs_dirent if found, NULL if not. |
| 690 | */ |
| 691 | struct sysfs_dirent *sysfs_get_dirent(struct sysfs_dirent *parent_sd, |
| 692 | const unsigned char *name) |
| 693 | { |
| 694 | struct sysfs_dirent *sd; |
| 695 | |
Tejun Heo | 3007e99 | 2007-06-14 04:27:23 +0900 | [diff] [blame] | 696 | mutex_lock(&sysfs_mutex); |
Tejun Heo | f0b0af4 | 2007-06-14 04:27:22 +0900 | [diff] [blame] | 697 | sd = sysfs_find_dirent(parent_sd, name); |
| 698 | sysfs_get(sd); |
Tejun Heo | 3007e99 | 2007-06-14 04:27:23 +0900 | [diff] [blame] | 699 | mutex_unlock(&sysfs_mutex); |
Tejun Heo | f0b0af4 | 2007-06-14 04:27:22 +0900 | [diff] [blame] | 700 | |
| 701 | return sd; |
Maneesh Soni | c516865 | 2006-03-09 19:40:14 +0530 | [diff] [blame] | 702 | } |
| 703 | |
Tejun Heo | 608e266 | 2007-06-14 04:27:22 +0900 | [diff] [blame] | 704 | static int create_dir(struct kobject *kobj, struct sysfs_dirent *parent_sd, |
| 705 | const char *name, struct sysfs_dirent **p_sd) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 706 | { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 707 | umode_t mode = S_IFDIR| S_IRWXU | S_IRUGO | S_IXUGO; |
Tejun Heo | 5122503 | 2007-06-14 04:27:25 +0900 | [diff] [blame] | 708 | struct sysfs_addrm_cxt acxt; |
Tejun Heo | dfeb9fb | 2007-06-14 03:45:14 +0900 | [diff] [blame] | 709 | struct sysfs_dirent *sd; |
Tejun Heo | 23dc279 | 2007-08-02 21:38:03 +0900 | [diff] [blame] | 710 | int rc; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 711 | |
Tejun Heo | fc9f54b | 2007-06-14 03:45:17 +0900 | [diff] [blame] | 712 | /* allocate */ |
Tejun Heo | 3e51903 | 2007-06-14 03:45:15 +0900 | [diff] [blame] | 713 | sd = sysfs_new_dirent(name, mode, SYSFS_DIR); |
Tejun Heo | a26cd72 | 2007-06-14 03:45:14 +0900 | [diff] [blame] | 714 | if (!sd) |
Tejun Heo | 5122503 | 2007-06-14 04:27:25 +0900 | [diff] [blame] | 715 | return -ENOMEM; |
Tejun Heo | 3e51903 | 2007-06-14 03:45:15 +0900 | [diff] [blame] | 716 | sd->s_elem.dir.kobj = kobj; |
Tejun Heo | dfeb9fb | 2007-06-14 03:45:14 +0900 | [diff] [blame] | 717 | |
Tejun Heo | 5122503 | 2007-06-14 04:27:25 +0900 | [diff] [blame] | 718 | /* link in */ |
| 719 | sysfs_addrm_start(&acxt, parent_sd); |
Tejun Heo | 23dc279 | 2007-08-02 21:38:03 +0900 | [diff] [blame] | 720 | rc = sysfs_add_one(&acxt, sd); |
| 721 | sysfs_addrm_finish(&acxt); |
Tejun Heo | 967e35d | 2007-07-18 16:38:11 +0900 | [diff] [blame] | 722 | |
Tejun Heo | 23dc279 | 2007-08-02 21:38:03 +0900 | [diff] [blame] | 723 | if (rc == 0) |
| 724 | *p_sd = sd; |
| 725 | else |
Tejun Heo | 967e35d | 2007-07-18 16:38:11 +0900 | [diff] [blame] | 726 | sysfs_put(sd); |
Tejun Heo | fc9f54b | 2007-06-14 03:45:17 +0900 | [diff] [blame] | 727 | |
Tejun Heo | 23dc279 | 2007-08-02 21:38:03 +0900 | [diff] [blame] | 728 | return rc; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 729 | } |
| 730 | |
Tejun Heo | 608e266 | 2007-06-14 04:27:22 +0900 | [diff] [blame] | 731 | int sysfs_create_subdir(struct kobject *kobj, const char *name, |
| 732 | struct sysfs_dirent **p_sd) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 733 | { |
Tejun Heo | 608e266 | 2007-06-14 04:27:22 +0900 | [diff] [blame] | 734 | return create_dir(kobj, kobj->sd, name, p_sd); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 735 | } |
| 736 | |
| 737 | /** |
| 738 | * sysfs_create_dir - create a directory for an object. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 739 | * @kobj: object we're creating directory for. |
| 740 | */ |
Eric W. Biederman | 90bc613 | 2007-07-31 19:15:08 +0900 | [diff] [blame] | 741 | int sysfs_create_dir(struct kobject * kobj) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 742 | { |
Tejun Heo | 608e266 | 2007-06-14 04:27:22 +0900 | [diff] [blame] | 743 | struct sysfs_dirent *parent_sd, *sd; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 744 | int error = 0; |
| 745 | |
| 746 | BUG_ON(!kobj); |
| 747 | |
Eric W. Biederman | 90bc613 | 2007-07-31 19:15:08 +0900 | [diff] [blame] | 748 | if (kobj->parent) |
Tejun Heo | 608e266 | 2007-06-14 04:27:22 +0900 | [diff] [blame] | 749 | parent_sd = kobj->parent->sd; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 750 | else |
Eric W. Biederman | 7d0c7d6 | 2007-08-20 21:36:30 +0900 | [diff] [blame] | 751 | parent_sd = &sysfs_root; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 752 | |
Tejun Heo | 608e266 | 2007-06-14 04:27:22 +0900 | [diff] [blame] | 753 | error = create_dir(kobj, parent_sd, kobject_name(kobj), &sd); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 754 | if (!error) |
Tejun Heo | 608e266 | 2007-06-14 04:27:22 +0900 | [diff] [blame] | 755 | kobj->sd = sd; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 756 | return error; |
| 757 | } |
| 758 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 759 | static struct dentry * sysfs_lookup(struct inode *dir, struct dentry *dentry, |
| 760 | struct nameidata *nd) |
| 761 | { |
Tejun Heo | 6cb5214 | 2007-07-31 19:15:08 +0900 | [diff] [blame] | 762 | struct dentry *ret = NULL; |
Tejun Heo | a7a0475 | 2007-08-02 21:38:02 +0900 | [diff] [blame] | 763 | struct sysfs_dirent *parent_sd = dentry->d_parent->d_fsdata; |
| 764 | struct sysfs_dirent *sd; |
Tejun Heo | fc9f54b | 2007-06-14 03:45:17 +0900 | [diff] [blame] | 765 | struct inode *inode; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 766 | |
Tejun Heo | 6cb5214 | 2007-07-31 19:15:08 +0900 | [diff] [blame] | 767 | mutex_lock(&sysfs_mutex); |
| 768 | |
Eric W. Biederman | 94777e0 | 2007-08-20 21:36:30 +0900 | [diff] [blame] | 769 | sd = sysfs_find_dirent(parent_sd, dentry->d_name.name); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 770 | |
Tejun Heo | fc9f54b | 2007-06-14 03:45:17 +0900 | [diff] [blame] | 771 | /* no such entry */ |
Tejun Heo | a7a0475 | 2007-08-02 21:38:02 +0900 | [diff] [blame] | 772 | if (!sd) |
Tejun Heo | 6cb5214 | 2007-07-31 19:15:08 +0900 | [diff] [blame] | 773 | goto out_unlock; |
Tejun Heo | fc9f54b | 2007-06-14 03:45:17 +0900 | [diff] [blame] | 774 | |
| 775 | /* attach dentry and inode */ |
Tejun Heo | 8312a8d | 2007-06-14 03:45:17 +0900 | [diff] [blame] | 776 | inode = sysfs_get_inode(sd); |
Tejun Heo | 6cb5214 | 2007-07-31 19:15:08 +0900 | [diff] [blame] | 777 | if (!inode) { |
| 778 | ret = ERR_PTR(-ENOMEM); |
| 779 | goto out_unlock; |
| 780 | } |
Tejun Heo | 3007e99 | 2007-06-14 04:27:23 +0900 | [diff] [blame] | 781 | |
Eric W. Biederman | 119dd52 | 2007-08-20 21:36:29 +0900 | [diff] [blame] | 782 | d_instantiate(dentry, inode); |
Tejun Heo | fc9f54b | 2007-06-14 03:45:17 +0900 | [diff] [blame] | 783 | sysfs_attach_dentry(sd, dentry); |
| 784 | |
Tejun Heo | 6cb5214 | 2007-07-31 19:15:08 +0900 | [diff] [blame] | 785 | out_unlock: |
Tejun Heo | 3007e99 | 2007-06-14 04:27:23 +0900 | [diff] [blame] | 786 | mutex_unlock(&sysfs_mutex); |
Tejun Heo | 6cb5214 | 2007-07-31 19:15:08 +0900 | [diff] [blame] | 787 | return ret; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 788 | } |
| 789 | |
Arjan van de Ven | c5ef1c4 | 2007-02-12 00:55:40 -0800 | [diff] [blame] | 790 | const struct inode_operations sysfs_dir_inode_operations = { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 791 | .lookup = sysfs_lookup, |
Maneesh Soni | 988d186 | 2005-05-31 10:39:14 +0530 | [diff] [blame] | 792 | .setattr = sysfs_setattr, |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 793 | }; |
| 794 | |
Tejun Heo | 608e266 | 2007-06-14 04:27:22 +0900 | [diff] [blame] | 795 | static void remove_dir(struct sysfs_dirent *sd) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 796 | { |
Tejun Heo | fb6896d | 2007-06-14 04:27:24 +0900 | [diff] [blame] | 797 | struct sysfs_addrm_cxt acxt; |
| 798 | |
| 799 | sysfs_addrm_start(&acxt, sd->s_parent); |
Tejun Heo | fb6896d | 2007-06-14 04:27:24 +0900 | [diff] [blame] | 800 | sysfs_remove_one(&acxt, sd); |
| 801 | sysfs_addrm_finish(&acxt); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 802 | } |
| 803 | |
Tejun Heo | 608e266 | 2007-06-14 04:27:22 +0900 | [diff] [blame] | 804 | void sysfs_remove_subdir(struct sysfs_dirent *sd) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 805 | { |
Tejun Heo | 608e266 | 2007-06-14 04:27:22 +0900 | [diff] [blame] | 806 | remove_dir(sd); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 807 | } |
| 808 | |
| 809 | |
Tejun Heo | 608e266 | 2007-06-14 04:27:22 +0900 | [diff] [blame] | 810 | static void __sysfs_remove_dir(struct sysfs_dirent *dir_sd) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 811 | { |
Tejun Heo | fb6896d | 2007-06-14 04:27:24 +0900 | [diff] [blame] | 812 | struct sysfs_addrm_cxt acxt; |
Tejun Heo | 0c73f18 | 2007-06-14 03:45:18 +0900 | [diff] [blame] | 813 | struct sysfs_dirent **pos; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 814 | |
Tejun Heo | 608e266 | 2007-06-14 04:27:22 +0900 | [diff] [blame] | 815 | if (!dir_sd) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 816 | return; |
| 817 | |
Tejun Heo | 608e266 | 2007-06-14 04:27:22 +0900 | [diff] [blame] | 818 | pr_debug("sysfs %s: removing dir\n", dir_sd->s_name); |
Tejun Heo | fb6896d | 2007-06-14 04:27:24 +0900 | [diff] [blame] | 819 | sysfs_addrm_start(&acxt, dir_sd); |
Tejun Heo | 608e266 | 2007-06-14 04:27:22 +0900 | [diff] [blame] | 820 | pos = &dir_sd->s_children; |
Tejun Heo | 0c73f18 | 2007-06-14 03:45:18 +0900 | [diff] [blame] | 821 | while (*pos) { |
| 822 | struct sysfs_dirent *sd = *pos; |
| 823 | |
Eric W. Biederman | 3efa65b | 2007-08-20 21:36:30 +0900 | [diff] [blame^] | 824 | if (sysfs_type(sd) != SYSFS_DIR) |
Tejun Heo | fb6896d | 2007-06-14 04:27:24 +0900 | [diff] [blame] | 825 | sysfs_remove_one(&acxt, sd); |
Tejun Heo | 41fc1c2 | 2007-08-02 21:38:03 +0900 | [diff] [blame] | 826 | else |
Tejun Heo | 0c73f18 | 2007-06-14 03:45:18 +0900 | [diff] [blame] | 827 | pos = &(*pos)->s_sibling; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 828 | } |
Tejun Heo | fb6896d | 2007-06-14 04:27:24 +0900 | [diff] [blame] | 829 | sysfs_addrm_finish(&acxt); |
Tejun Heo | 0ab6608 | 2007-06-14 03:45:16 +0900 | [diff] [blame] | 830 | |
Tejun Heo | 608e266 | 2007-06-14 04:27:22 +0900 | [diff] [blame] | 831 | remove_dir(dir_sd); |
Eric W. Biederman | b592fcf | 2007-01-24 12:35:52 -0700 | [diff] [blame] | 832 | } |
| 833 | |
| 834 | /** |
| 835 | * sysfs_remove_dir - remove an object's directory. |
| 836 | * @kobj: object. |
| 837 | * |
| 838 | * The only thing special about this is that we remove any files in |
| 839 | * the directory before we remove the directory, and we've inlined |
| 840 | * what used to be sysfs_rmdir() below, instead of calling separately. |
| 841 | */ |
| 842 | |
| 843 | void sysfs_remove_dir(struct kobject * kobj) |
| 844 | { |
Tejun Heo | 608e266 | 2007-06-14 04:27:22 +0900 | [diff] [blame] | 845 | struct sysfs_dirent *sd = kobj->sd; |
Tejun Heo | aecdced | 2007-06-14 03:45:15 +0900 | [diff] [blame] | 846 | |
Tejun Heo | 5f99532 | 2007-06-14 04:27:23 +0900 | [diff] [blame] | 847 | spin_lock(&sysfs_assoc_lock); |
Tejun Heo | 608e266 | 2007-06-14 04:27:22 +0900 | [diff] [blame] | 848 | kobj->sd = NULL; |
Tejun Heo | 5f99532 | 2007-06-14 04:27:23 +0900 | [diff] [blame] | 849 | spin_unlock(&sysfs_assoc_lock); |
Tejun Heo | aecdced | 2007-06-14 03:45:15 +0900 | [diff] [blame] | 850 | |
Tejun Heo | 608e266 | 2007-06-14 04:27:22 +0900 | [diff] [blame] | 851 | __sysfs_remove_dir(sd); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 852 | } |
| 853 | |
Eric W. Biederman | 90bc613 | 2007-07-31 19:15:08 +0900 | [diff] [blame] | 854 | int sysfs_rename_dir(struct kobject * kobj, const char *new_name) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 855 | { |
Eric W. Biederman | 90bc613 | 2007-07-31 19:15:08 +0900 | [diff] [blame] | 856 | struct sysfs_dirent *sd; |
| 857 | struct dentry *parent = NULL; |
Tejun Heo | 5122503 | 2007-06-14 04:27:25 +0900 | [diff] [blame] | 858 | struct dentry *old_dentry = NULL, *new_dentry = NULL; |
| 859 | const char *dup_name = NULL; |
Tejun Heo | 996b737 | 2007-06-14 03:45:14 +0900 | [diff] [blame] | 860 | int error; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 861 | |
Tejun Heo | ff869de | 2007-08-02 21:38:02 +0900 | [diff] [blame] | 862 | /* get the original dentry */ |
Eric W. Biederman | 90bc613 | 2007-07-31 19:15:08 +0900 | [diff] [blame] | 863 | sd = kobj->sd; |
Tejun Heo | 5122503 | 2007-06-14 04:27:25 +0900 | [diff] [blame] | 864 | old_dentry = sysfs_get_dentry(sd); |
| 865 | if (IS_ERR(old_dentry)) { |
| 866 | error = PTR_ERR(old_dentry); |
| 867 | goto out_dput; |
| 868 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 869 | |
Tejun Heo | ff869de | 2007-08-02 21:38:02 +0900 | [diff] [blame] | 870 | parent = old_dentry->d_parent; |
Tejun Heo | 5122503 | 2007-06-14 04:27:25 +0900 | [diff] [blame] | 871 | |
Eric W. Biederman | 90bc613 | 2007-07-31 19:15:08 +0900 | [diff] [blame] | 872 | /* lock parent and get dentry for new name */ |
| 873 | mutex_lock(&parent->d_inode->i_mutex); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 874 | |
Eric W. Biederman | 90bc613 | 2007-07-31 19:15:08 +0900 | [diff] [blame] | 875 | new_dentry = lookup_one_len(new_name, parent, strlen(new_name)); |
Tejun Heo | 996b737 | 2007-06-14 03:45:14 +0900 | [diff] [blame] | 876 | if (IS_ERR(new_dentry)) { |
| 877 | error = PTR_ERR(new_dentry); |
| 878 | goto out_unlock; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 879 | } |
Tejun Heo | 996b737 | 2007-06-14 03:45:14 +0900 | [diff] [blame] | 880 | |
Tejun Heo | 996b737 | 2007-06-14 03:45:14 +0900 | [diff] [blame] | 881 | error = -EINVAL; |
Eric W. Biederman | 90bc613 | 2007-07-31 19:15:08 +0900 | [diff] [blame] | 882 | if (old_dentry == new_dentry) |
Tejun Heo | 5122503 | 2007-06-14 04:27:25 +0900 | [diff] [blame] | 883 | goto out_unlock; |
Tejun Heo | 996b737 | 2007-06-14 03:45:14 +0900 | [diff] [blame] | 884 | |
| 885 | error = -EEXIST; |
| 886 | if (new_dentry->d_inode) |
Tejun Heo | 5122503 | 2007-06-14 04:27:25 +0900 | [diff] [blame] | 887 | goto out_unlock; |
Tejun Heo | 996b737 | 2007-06-14 03:45:14 +0900 | [diff] [blame] | 888 | |
Tejun Heo | 0c096b5 | 2007-06-14 03:45:15 +0900 | [diff] [blame] | 889 | /* rename kobject and sysfs_dirent */ |
| 890 | error = -ENOMEM; |
| 891 | new_name = dup_name = kstrdup(new_name, GFP_KERNEL); |
| 892 | if (!new_name) |
Tejun Heo | 996b737 | 2007-06-14 03:45:14 +0900 | [diff] [blame] | 893 | goto out_drop; |
| 894 | |
Tejun Heo | 0c096b5 | 2007-06-14 03:45:15 +0900 | [diff] [blame] | 895 | error = kobject_set_name(kobj, "%s", new_name); |
| 896 | if (error) |
Tejun Heo | 5122503 | 2007-06-14 04:27:25 +0900 | [diff] [blame] | 897 | goto out_drop; |
Tejun Heo | 0c096b5 | 2007-06-14 03:45:15 +0900 | [diff] [blame] | 898 | |
Tejun Heo | 6cb5214 | 2007-07-31 19:15:08 +0900 | [diff] [blame] | 899 | mutex_lock(&sysfs_mutex); |
Tejun Heo | 5122503 | 2007-06-14 04:27:25 +0900 | [diff] [blame] | 900 | dup_name = sd->s_name; |
Tejun Heo | 0c096b5 | 2007-06-14 03:45:15 +0900 | [diff] [blame] | 901 | sd->s_name = new_name; |
Tejun Heo | ff869de | 2007-08-02 21:38:02 +0900 | [diff] [blame] | 902 | mutex_unlock(&sysfs_mutex); |
Tejun Heo | 0c096b5 | 2007-06-14 03:45:15 +0900 | [diff] [blame] | 903 | |
Tejun Heo | ff869de | 2007-08-02 21:38:02 +0900 | [diff] [blame] | 904 | /* rename */ |
Tejun Heo | 996b737 | 2007-06-14 03:45:14 +0900 | [diff] [blame] | 905 | d_add(new_dentry, NULL); |
Tejun Heo | 608e266 | 2007-06-14 04:27:22 +0900 | [diff] [blame] | 906 | d_move(sd->s_dentry, new_dentry); |
Tejun Heo | 996b737 | 2007-06-14 03:45:14 +0900 | [diff] [blame] | 907 | |
Tejun Heo | 996b737 | 2007-06-14 03:45:14 +0900 | [diff] [blame] | 908 | error = 0; |
| 909 | goto out_unlock; |
| 910 | |
| 911 | out_drop: |
| 912 | d_drop(new_dentry); |
Tejun Heo | 996b737 | 2007-06-14 03:45:14 +0900 | [diff] [blame] | 913 | out_unlock: |
Eric W. Biederman | 90bc613 | 2007-07-31 19:15:08 +0900 | [diff] [blame] | 914 | mutex_unlock(&parent->d_inode->i_mutex); |
Tejun Heo | 5122503 | 2007-06-14 04:27:25 +0900 | [diff] [blame] | 915 | out_dput: |
| 916 | kfree(dup_name); |
Tejun Heo | 5122503 | 2007-06-14 04:27:25 +0900 | [diff] [blame] | 917 | dput(old_dentry); |
| 918 | dput(new_dentry); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 919 | return error; |
| 920 | } |
| 921 | |
Tejun Heo | 5122503 | 2007-06-14 04:27:25 +0900 | [diff] [blame] | 922 | int sysfs_move_dir(struct kobject *kobj, struct kobject *new_parent_kobj) |
Cornelia Huck | 8a82472 | 2006-11-20 17:07:51 +0100 | [diff] [blame] | 923 | { |
Tejun Heo | 5122503 | 2007-06-14 04:27:25 +0900 | [diff] [blame] | 924 | struct sysfs_dirent *sd = kobj->sd; |
| 925 | struct sysfs_dirent *new_parent_sd; |
| 926 | struct dentry *old_parent, *new_parent = NULL; |
| 927 | struct dentry *old_dentry = NULL, *new_dentry = NULL; |
Cornelia Huck | 8a82472 | 2006-11-20 17:07:51 +0100 | [diff] [blame] | 928 | int error; |
| 929 | |
Tejun Heo | 5122503 | 2007-06-14 04:27:25 +0900 | [diff] [blame] | 930 | BUG_ON(!sd->s_parent); |
| 931 | new_parent_sd = new_parent_kobj->sd ? new_parent_kobj->sd : &sysfs_root; |
Cornelia Huck | 8a82472 | 2006-11-20 17:07:51 +0100 | [diff] [blame] | 932 | |
Tejun Heo | 5122503 | 2007-06-14 04:27:25 +0900 | [diff] [blame] | 933 | /* get dentries */ |
| 934 | old_dentry = sysfs_get_dentry(sd); |
| 935 | if (IS_ERR(old_dentry)) { |
| 936 | error = PTR_ERR(old_dentry); |
| 937 | goto out_dput; |
| 938 | } |
| 939 | old_parent = sd->s_parent->s_dentry; |
| 940 | |
| 941 | new_parent = sysfs_get_dentry(new_parent_sd); |
| 942 | if (IS_ERR(new_parent)) { |
| 943 | error = PTR_ERR(new_parent); |
| 944 | goto out_dput; |
| 945 | } |
| 946 | |
| 947 | if (old_parent->d_inode == new_parent->d_inode) { |
| 948 | error = 0; |
| 949 | goto out_dput; /* nothing to move */ |
| 950 | } |
Cornelia Huck | 8a82472 | 2006-11-20 17:07:51 +0100 | [diff] [blame] | 951 | again: |
Tejun Heo | 5122503 | 2007-06-14 04:27:25 +0900 | [diff] [blame] | 952 | mutex_lock(&old_parent->d_inode->i_mutex); |
| 953 | if (!mutex_trylock(&new_parent->d_inode->i_mutex)) { |
| 954 | mutex_unlock(&old_parent->d_inode->i_mutex); |
Cornelia Huck | 8a82472 | 2006-11-20 17:07:51 +0100 | [diff] [blame] | 955 | goto again; |
| 956 | } |
| 957 | |
Greg Kroah-Hartman | 19c38de | 2007-09-12 15:06:57 -0700 | [diff] [blame] | 958 | new_dentry = lookup_one_len(kobject_name(kobj), new_parent, strlen(kobject_name(kobj))); |
Cornelia Huck | 8a82472 | 2006-11-20 17:07:51 +0100 | [diff] [blame] | 959 | if (IS_ERR(new_dentry)) { |
| 960 | error = PTR_ERR(new_dentry); |
Tejun Heo | 5122503 | 2007-06-14 04:27:25 +0900 | [diff] [blame] | 961 | goto out_unlock; |
Cornelia Huck | 8a82472 | 2006-11-20 17:07:51 +0100 | [diff] [blame] | 962 | } else |
| 963 | error = 0; |
| 964 | d_add(new_dentry, NULL); |
Tejun Heo | 608e266 | 2007-06-14 04:27:22 +0900 | [diff] [blame] | 965 | d_move(sd->s_dentry, new_dentry); |
Cornelia Huck | 8a82472 | 2006-11-20 17:07:51 +0100 | [diff] [blame] | 966 | dput(new_dentry); |
| 967 | |
| 968 | /* Remove from old parent's list and insert into new parent's list. */ |
Tejun Heo | 3007e99 | 2007-06-14 04:27:23 +0900 | [diff] [blame] | 969 | mutex_lock(&sysfs_mutex); |
| 970 | |
Tejun Heo | 0c73f18 | 2007-06-14 03:45:18 +0900 | [diff] [blame] | 971 | sysfs_unlink_sibling(sd); |
Tejun Heo | 7f7cfff | 2007-06-14 03:45:17 +0900 | [diff] [blame] | 972 | sysfs_get(new_parent_sd); |
| 973 | sysfs_put(sd->s_parent); |
| 974 | sd->s_parent = new_parent_sd; |
Tejun Heo | 0c73f18 | 2007-06-14 03:45:18 +0900 | [diff] [blame] | 975 | sysfs_link_sibling(sd); |
Cornelia Huck | 8a82472 | 2006-11-20 17:07:51 +0100 | [diff] [blame] | 976 | |
Tejun Heo | 3007e99 | 2007-06-14 04:27:23 +0900 | [diff] [blame] | 977 | mutex_unlock(&sysfs_mutex); |
Cornelia Huck | 8a82472 | 2006-11-20 17:07:51 +0100 | [diff] [blame] | 978 | |
Tejun Heo | 5122503 | 2007-06-14 04:27:25 +0900 | [diff] [blame] | 979 | out_unlock: |
| 980 | mutex_unlock(&new_parent->d_inode->i_mutex); |
| 981 | mutex_unlock(&old_parent->d_inode->i_mutex); |
| 982 | out_dput: |
| 983 | dput(new_parent); |
| 984 | dput(old_dentry); |
| 985 | dput(new_dentry); |
Cornelia Huck | 8a82472 | 2006-11-20 17:07:51 +0100 | [diff] [blame] | 986 | return error; |
| 987 | } |
| 988 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 989 | /* Relationship between s_mode and the DT_xxx types */ |
| 990 | static inline unsigned char dt_type(struct sysfs_dirent *sd) |
| 991 | { |
| 992 | return (sd->s_mode >> 12) & 15; |
| 993 | } |
| 994 | |
| 995 | static int sysfs_readdir(struct file * filp, void * dirent, filldir_t filldir) |
| 996 | { |
Josef "Jeff" Sipek | f427f5d | 2006-12-08 02:36:36 -0800 | [diff] [blame] | 997 | struct dentry *dentry = filp->f_path.dentry; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 998 | struct sysfs_dirent * parent_sd = dentry->d_fsdata; |
Eric W. Biederman | 3efa65b | 2007-08-20 21:36:30 +0900 | [diff] [blame^] | 999 | struct sysfs_dirent *pos; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1000 | ino_t ino; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1001 | |
Eric W. Biederman | 3efa65b | 2007-08-20 21:36:30 +0900 | [diff] [blame^] | 1002 | if (filp->f_pos == 0) { |
| 1003 | ino = parent_sd->s_ino; |
| 1004 | if (filldir(dirent, ".", 1, filp->f_pos, ino, DT_DIR) == 0) |
| 1005 | filp->f_pos++; |
| 1006 | } |
| 1007 | if (filp->f_pos == 1) { |
| 1008 | if (parent_sd->s_parent) |
| 1009 | ino = parent_sd->s_parent->s_ino; |
| 1010 | else |
Eric Sandeen | dc35125 | 2007-06-11 14:02:45 +0900 | [diff] [blame] | 1011 | ino = parent_sd->s_ino; |
Eric W. Biederman | 3efa65b | 2007-08-20 21:36:30 +0900 | [diff] [blame^] | 1012 | if (filldir(dirent, "..", 2, filp->f_pos, ino, DT_DIR) == 0) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1013 | filp->f_pos++; |
Eric W. Biederman | 3efa65b | 2007-08-20 21:36:30 +0900 | [diff] [blame^] | 1014 | } |
| 1015 | if ((filp->f_pos > 1) && (filp->f_pos < INT_MAX)) { |
| 1016 | mutex_lock(&sysfs_mutex); |
| 1017 | |
| 1018 | /* Skip the dentries we have already reported */ |
| 1019 | pos = parent_sd->s_children; |
| 1020 | while (pos && (filp->f_pos > pos->s_ino)) |
| 1021 | pos = pos->s_sibling; |
| 1022 | |
| 1023 | for ( ; pos; pos = pos->s_sibling) { |
| 1024 | const char * name; |
| 1025 | int len; |
| 1026 | |
| 1027 | name = pos->s_name; |
| 1028 | len = strlen(name); |
| 1029 | filp->f_pos = ino = pos->s_ino; |
| 1030 | |
| 1031 | if (filldir(dirent, name, len, filp->f_pos, ino, |
| 1032 | dt_type(pos)) < 0) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1033 | break; |
Eric W. Biederman | 3efa65b | 2007-08-20 21:36:30 +0900 | [diff] [blame^] | 1034 | } |
| 1035 | if (!pos) |
| 1036 | filp->f_pos = INT_MAX; |
| 1037 | mutex_unlock(&sysfs_mutex); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1038 | } |
| 1039 | return 0; |
| 1040 | } |
| 1041 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1042 | |
Arjan van de Ven | 4b6f5d2 | 2006-03-28 01:56:42 -0800 | [diff] [blame] | 1043 | const struct file_operations sysfs_dir_operations = { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1044 | .read = generic_read_dir, |
| 1045 | .readdir = sysfs_readdir, |
| 1046 | }; |