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); |
Eric W. Biederman | 932ea2e | 2007-08-20 21:36:30 +0900 | [diff] [blame] | 18 | DEFINE_MUTEX(sysfs_rename_mutex); |
Tejun Heo | 5f99532 | 2007-06-14 04:27:23 +0900 | [diff] [blame] | 19 | spinlock_t sysfs_assoc_lock = SPIN_LOCK_UNLOCKED; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 20 | |
Tejun Heo | 2b611bb | 2007-06-14 03:45:13 +0900 | [diff] [blame] | 21 | static spinlock_t sysfs_ino_lock = SPIN_LOCK_UNLOCKED; |
| 22 | static DEFINE_IDA(sysfs_ino_ida); |
| 23 | |
Tejun Heo | b6b4a43 | 2007-06-14 03:45:18 +0900 | [diff] [blame] | 24 | /** |
Tejun Heo | 0c73f18 | 2007-06-14 03:45:18 +0900 | [diff] [blame] | 25 | * sysfs_link_sibling - link sysfs_dirent into sibling list |
| 26 | * @sd: sysfs_dirent of interest |
| 27 | * |
| 28 | * Link @sd into its sibling list which starts from |
Tejun Heo | bc747f3 | 2007-09-20 16:05:12 +0900 | [diff] [blame^] | 29 | * sd->s_parent->s_dir.children. |
Tejun Heo | 0c73f18 | 2007-06-14 03:45:18 +0900 | [diff] [blame] | 30 | * |
| 31 | * Locking: |
Tejun Heo | 3007e99 | 2007-06-14 04:27:23 +0900 | [diff] [blame] | 32 | * mutex_lock(sysfs_mutex) |
Tejun Heo | 0c73f18 | 2007-06-14 03:45:18 +0900 | [diff] [blame] | 33 | */ |
Tejun Heo | 41fc1c2 | 2007-08-02 21:38:03 +0900 | [diff] [blame] | 34 | static void sysfs_link_sibling(struct sysfs_dirent *sd) |
Tejun Heo | 0c73f18 | 2007-06-14 03:45:18 +0900 | [diff] [blame] | 35 | { |
| 36 | struct sysfs_dirent *parent_sd = sd->s_parent; |
Eric W. Biederman | 3efa65b | 2007-08-20 21:36:30 +0900 | [diff] [blame] | 37 | struct sysfs_dirent **pos; |
Tejun Heo | 0c73f18 | 2007-06-14 03:45:18 +0900 | [diff] [blame] | 38 | |
| 39 | BUG_ON(sd->s_sibling); |
Eric W. Biederman | 3efa65b | 2007-08-20 21:36:30 +0900 | [diff] [blame] | 40 | |
| 41 | /* Store directory entries in order by ino. This allows |
| 42 | * readdir to properly restart without having to add a |
Tejun Heo | bc747f3 | 2007-09-20 16:05:12 +0900 | [diff] [blame^] | 43 | * cursor into the s_dir.children list. |
Eric W. Biederman | 3efa65b | 2007-08-20 21:36:30 +0900 | [diff] [blame] | 44 | */ |
Tejun Heo | bc747f3 | 2007-09-20 16:05:12 +0900 | [diff] [blame^] | 45 | for (pos = &parent_sd->s_dir.children; *pos; pos = &(*pos)->s_sibling) { |
Eric W. Biederman | 3efa65b | 2007-08-20 21:36:30 +0900 | [diff] [blame] | 46 | if (sd->s_ino < (*pos)->s_ino) |
| 47 | break; |
| 48 | } |
| 49 | sd->s_sibling = *pos; |
| 50 | *pos = sd; |
Tejun Heo | 0c73f18 | 2007-06-14 03:45:18 +0900 | [diff] [blame] | 51 | } |
| 52 | |
| 53 | /** |
| 54 | * sysfs_unlink_sibling - unlink sysfs_dirent from sibling list |
| 55 | * @sd: sysfs_dirent of interest |
| 56 | * |
| 57 | * Unlink @sd from its sibling list which starts from |
Tejun Heo | bc747f3 | 2007-09-20 16:05:12 +0900 | [diff] [blame^] | 58 | * sd->s_parent->s_dir.children. |
Tejun Heo | 0c73f18 | 2007-06-14 03:45:18 +0900 | [diff] [blame] | 59 | * |
| 60 | * Locking: |
Tejun Heo | 3007e99 | 2007-06-14 04:27:23 +0900 | [diff] [blame] | 61 | * mutex_lock(sysfs_mutex) |
Tejun Heo | 0c73f18 | 2007-06-14 03:45:18 +0900 | [diff] [blame] | 62 | */ |
Tejun Heo | 41fc1c2 | 2007-08-02 21:38:03 +0900 | [diff] [blame] | 63 | static void sysfs_unlink_sibling(struct sysfs_dirent *sd) |
Tejun Heo | 0c73f18 | 2007-06-14 03:45:18 +0900 | [diff] [blame] | 64 | { |
| 65 | struct sysfs_dirent **pos; |
| 66 | |
Tejun Heo | bc747f3 | 2007-09-20 16:05:12 +0900 | [diff] [blame^] | 67 | for (pos = &sd->s_parent->s_dir.children; *pos; |
| 68 | pos = &(*pos)->s_sibling) { |
Tejun Heo | 0c73f18 | 2007-06-14 03:45:18 +0900 | [diff] [blame] | 69 | if (*pos == sd) { |
| 70 | *pos = sd->s_sibling; |
| 71 | sd->s_sibling = NULL; |
| 72 | break; |
| 73 | } |
| 74 | } |
| 75 | } |
| 76 | |
| 77 | /** |
Tejun Heo | 53e0ae9 | 2007-06-14 04:27:25 +0900 | [diff] [blame] | 78 | * sysfs_get_dentry - get dentry for the given sysfs_dirent |
| 79 | * @sd: sysfs_dirent of interest |
| 80 | * |
| 81 | * Get dentry for @sd. Dentry is looked up if currently not |
Tejun Heo | e0712bb | 2007-08-20 21:36:30 +0900 | [diff] [blame] | 82 | * present. This function descends from the root looking up |
| 83 | * dentry for each step. |
Tejun Heo | 53e0ae9 | 2007-06-14 04:27:25 +0900 | [diff] [blame] | 84 | * |
| 85 | * LOCKING: |
Eric W. Biederman | 932ea2e | 2007-08-20 21:36:30 +0900 | [diff] [blame] | 86 | * mutex_lock(sysfs_rename_mutex) |
Tejun Heo | 53e0ae9 | 2007-06-14 04:27:25 +0900 | [diff] [blame] | 87 | * |
| 88 | * RETURNS: |
| 89 | * Pointer to found dentry on success, ERR_PTR() value on error. |
| 90 | */ |
| 91 | struct dentry *sysfs_get_dentry(struct sysfs_dirent *sd) |
| 92 | { |
Tejun Heo | e0712bb | 2007-08-20 21:36:30 +0900 | [diff] [blame] | 93 | struct dentry *dentry = dget(sysfs_sb->s_root); |
Tejun Heo | 53e0ae9 | 2007-06-14 04:27:25 +0900 | [diff] [blame] | 94 | |
Tejun Heo | e0712bb | 2007-08-20 21:36:30 +0900 | [diff] [blame] | 95 | while (dentry->d_fsdata != sd) { |
| 96 | struct sysfs_dirent *cur; |
| 97 | struct dentry *parent; |
Tejun Heo | 53e0ae9 | 2007-06-14 04:27:25 +0900 | [diff] [blame] | 98 | |
Tejun Heo | e0712bb | 2007-08-20 21:36:30 +0900 | [diff] [blame] | 99 | /* find the first ancestor which hasn't been looked up */ |
| 100 | cur = sd; |
| 101 | while (cur->s_parent != dentry->d_fsdata) |
Tejun Heo | 53e0ae9 | 2007-06-14 04:27:25 +0900 | [diff] [blame] | 102 | cur = cur->s_parent; |
| 103 | |
Tejun Heo | 53e0ae9 | 2007-06-14 04:27:25 +0900 | [diff] [blame] | 104 | /* look it up */ |
Tejun Heo | e0712bb | 2007-08-20 21:36:30 +0900 | [diff] [blame] | 105 | parent = dentry; |
| 106 | mutex_lock(&parent->d_inode->i_mutex); |
| 107 | dentry = lookup_one_len_kern(cur->s_name, parent, |
Tejun Heo | 53e0ae9 | 2007-06-14 04:27:25 +0900 | [diff] [blame] | 108 | strlen(cur->s_name)); |
Tejun Heo | e0712bb | 2007-08-20 21:36:30 +0900 | [diff] [blame] | 109 | mutex_unlock(&parent->d_inode->i_mutex); |
| 110 | dput(parent); |
Tejun Heo | 53e0ae9 | 2007-06-14 04:27:25 +0900 | [diff] [blame] | 111 | |
Tejun Heo | e0712bb | 2007-08-20 21:36:30 +0900 | [diff] [blame] | 112 | if (IS_ERR(dentry)) |
| 113 | break; |
Tejun Heo | 53e0ae9 | 2007-06-14 04:27:25 +0900 | [diff] [blame] | 114 | } |
Tejun Heo | 53e0ae9 | 2007-06-14 04:27:25 +0900 | [diff] [blame] | 115 | return dentry; |
| 116 | } |
| 117 | |
| 118 | /** |
Tejun Heo | b6b4a43 | 2007-06-14 03:45:18 +0900 | [diff] [blame] | 119 | * sysfs_get_active - get an active reference to sysfs_dirent |
| 120 | * @sd: sysfs_dirent to get an active reference to |
| 121 | * |
| 122 | * Get an active reference of @sd. This function is noop if @sd |
| 123 | * is NULL. |
| 124 | * |
| 125 | * RETURNS: |
| 126 | * Pointer to @sd on success, NULL on failure. |
| 127 | */ |
| 128 | struct sysfs_dirent *sysfs_get_active(struct sysfs_dirent *sd) |
| 129 | { |
Tejun Heo | 8619f97 | 2007-06-14 03:45:18 +0900 | [diff] [blame] | 130 | if (unlikely(!sd)) |
| 131 | return NULL; |
| 132 | |
| 133 | while (1) { |
| 134 | int v, t; |
| 135 | |
| 136 | v = atomic_read(&sd->s_active); |
| 137 | if (unlikely(v < 0)) |
| 138 | return NULL; |
| 139 | |
| 140 | t = atomic_cmpxchg(&sd->s_active, v, v + 1); |
| 141 | if (likely(t == v)) |
| 142 | return sd; |
| 143 | if (t < 0) |
| 144 | return NULL; |
| 145 | |
| 146 | cpu_relax(); |
Tejun Heo | b6b4a43 | 2007-06-14 03:45:18 +0900 | [diff] [blame] | 147 | } |
Tejun Heo | b6b4a43 | 2007-06-14 03:45:18 +0900 | [diff] [blame] | 148 | } |
| 149 | |
| 150 | /** |
| 151 | * sysfs_put_active - put an active reference to sysfs_dirent |
| 152 | * @sd: sysfs_dirent to put an active reference to |
| 153 | * |
| 154 | * Put an active reference to @sd. This function is noop if @sd |
| 155 | * is NULL. |
| 156 | */ |
| 157 | void sysfs_put_active(struct sysfs_dirent *sd) |
| 158 | { |
Tejun Heo | 8619f97 | 2007-06-14 03:45:18 +0900 | [diff] [blame] | 159 | struct completion *cmpl; |
| 160 | int v; |
| 161 | |
| 162 | if (unlikely(!sd)) |
| 163 | return; |
| 164 | |
| 165 | v = atomic_dec_return(&sd->s_active); |
| 166 | if (likely(v != SD_DEACTIVATED_BIAS)) |
| 167 | return; |
| 168 | |
| 169 | /* atomic_dec_return() is a mb(), we'll always see the updated |
Tejun Heo | 0c73f18 | 2007-06-14 03:45:18 +0900 | [diff] [blame] | 170 | * sd->s_sibling. |
Tejun Heo | 8619f97 | 2007-06-14 03:45:18 +0900 | [diff] [blame] | 171 | */ |
Tejun Heo | 0c73f18 | 2007-06-14 03:45:18 +0900 | [diff] [blame] | 172 | cmpl = (void *)sd->s_sibling; |
Tejun Heo | 8619f97 | 2007-06-14 03:45:18 +0900 | [diff] [blame] | 173 | complete(cmpl); |
Tejun Heo | b6b4a43 | 2007-06-14 03:45:18 +0900 | [diff] [blame] | 174 | } |
| 175 | |
| 176 | /** |
| 177 | * sysfs_get_active_two - get active references to sysfs_dirent and parent |
| 178 | * @sd: sysfs_dirent of interest |
| 179 | * |
| 180 | * Get active reference to @sd and its parent. Parent's active |
| 181 | * reference is grabbed first. This function is noop if @sd is |
| 182 | * NULL. |
| 183 | * |
| 184 | * RETURNS: |
| 185 | * Pointer to @sd on success, NULL on failure. |
| 186 | */ |
| 187 | struct sysfs_dirent *sysfs_get_active_two(struct sysfs_dirent *sd) |
| 188 | { |
| 189 | if (sd) { |
| 190 | if (sd->s_parent && unlikely(!sysfs_get_active(sd->s_parent))) |
| 191 | return NULL; |
| 192 | if (unlikely(!sysfs_get_active(sd))) { |
| 193 | sysfs_put_active(sd->s_parent); |
| 194 | return NULL; |
| 195 | } |
| 196 | } |
| 197 | return sd; |
| 198 | } |
| 199 | |
| 200 | /** |
| 201 | * sysfs_put_active_two - put active references to sysfs_dirent and parent |
| 202 | * @sd: sysfs_dirent of interest |
| 203 | * |
| 204 | * Put active references to @sd and its parent. This function is |
| 205 | * noop if @sd is NULL. |
| 206 | */ |
| 207 | void sysfs_put_active_two(struct sysfs_dirent *sd) |
| 208 | { |
| 209 | if (sd) { |
| 210 | sysfs_put_active(sd); |
| 211 | sysfs_put_active(sd->s_parent); |
| 212 | } |
| 213 | } |
| 214 | |
| 215 | /** |
| 216 | * sysfs_deactivate - deactivate sysfs_dirent |
| 217 | * @sd: sysfs_dirent to deactivate |
| 218 | * |
Tejun Heo | 8619f97 | 2007-06-14 03:45:18 +0900 | [diff] [blame] | 219 | * Deny new active references and drain existing ones. |
Tejun Heo | b6b4a43 | 2007-06-14 03:45:18 +0900 | [diff] [blame] | 220 | */ |
Tejun Heo | fb6896da | 2007-06-14 04:27:24 +0900 | [diff] [blame] | 221 | static void sysfs_deactivate(struct sysfs_dirent *sd) |
Tejun Heo | b6b4a43 | 2007-06-14 03:45:18 +0900 | [diff] [blame] | 222 | { |
Tejun Heo | 8619f97 | 2007-06-14 03:45:18 +0900 | [diff] [blame] | 223 | DECLARE_COMPLETION_ONSTACK(wait); |
| 224 | int v; |
Tejun Heo | b6b4a43 | 2007-06-14 03:45:18 +0900 | [diff] [blame] | 225 | |
Tejun Heo | 380e6fb | 2007-06-14 04:27:22 +0900 | [diff] [blame] | 226 | BUG_ON(sd->s_sibling || !(sd->s_flags & SYSFS_FLAG_REMOVED)); |
Tejun Heo | 0c73f18 | 2007-06-14 03:45:18 +0900 | [diff] [blame] | 227 | sd->s_sibling = (void *)&wait; |
Tejun Heo | 8619f97 | 2007-06-14 03:45:18 +0900 | [diff] [blame] | 228 | |
| 229 | /* atomic_add_return() is a mb(), put_active() will always see |
Tejun Heo | 0c73f18 | 2007-06-14 03:45:18 +0900 | [diff] [blame] | 230 | * the updated sd->s_sibling. |
Tejun Heo | b6b4a43 | 2007-06-14 03:45:18 +0900 | [diff] [blame] | 231 | */ |
Tejun Heo | 8619f97 | 2007-06-14 03:45:18 +0900 | [diff] [blame] | 232 | v = atomic_add_return(SD_DEACTIVATED_BIAS, &sd->s_active); |
| 233 | |
| 234 | if (v != SD_DEACTIVATED_BIAS) |
| 235 | wait_for_completion(&wait); |
| 236 | |
Tejun Heo | 0c73f18 | 2007-06-14 03:45:18 +0900 | [diff] [blame] | 237 | sd->s_sibling = NULL; |
Tejun Heo | b6b4a43 | 2007-06-14 03:45:18 +0900 | [diff] [blame] | 238 | } |
| 239 | |
Tejun Heo | 42b37df | 2007-06-14 03:45:17 +0900 | [diff] [blame] | 240 | static int sysfs_alloc_ino(ino_t *pino) |
Tejun Heo | 2b611bb | 2007-06-14 03:45:13 +0900 | [diff] [blame] | 241 | { |
| 242 | int ino, rc; |
| 243 | |
| 244 | retry: |
| 245 | spin_lock(&sysfs_ino_lock); |
| 246 | rc = ida_get_new_above(&sysfs_ino_ida, 2, &ino); |
| 247 | spin_unlock(&sysfs_ino_lock); |
| 248 | |
| 249 | if (rc == -EAGAIN) { |
| 250 | if (ida_pre_get(&sysfs_ino_ida, GFP_KERNEL)) |
| 251 | goto retry; |
| 252 | rc = -ENOMEM; |
| 253 | } |
| 254 | |
| 255 | *pino = ino; |
| 256 | return rc; |
| 257 | } |
| 258 | |
| 259 | static void sysfs_free_ino(ino_t ino) |
| 260 | { |
| 261 | spin_lock(&sysfs_ino_lock); |
| 262 | ida_remove(&sysfs_ino_ida, ino); |
| 263 | spin_unlock(&sysfs_ino_lock); |
| 264 | } |
| 265 | |
Tejun Heo | fa7f912 | 2007-06-14 03:45:13 +0900 | [diff] [blame] | 266 | void release_sysfs_dirent(struct sysfs_dirent * sd) |
| 267 | { |
Tejun Heo | 13b3086 | 2007-06-14 03:45:14 +0900 | [diff] [blame] | 268 | struct sysfs_dirent *parent_sd; |
| 269 | |
| 270 | repeat: |
Tejun Heo | 3007e99 | 2007-06-14 04:27:23 +0900 | [diff] [blame] | 271 | /* Moving/renaming is always done while holding reference. |
| 272 | * sd->s_parent won't change beneath us. |
| 273 | */ |
Tejun Heo | 13b3086 | 2007-06-14 03:45:14 +0900 | [diff] [blame] | 274 | parent_sd = sd->s_parent; |
| 275 | |
Tejun Heo | b402d72 | 2007-06-14 04:27:21 +0900 | [diff] [blame] | 276 | if (sysfs_type(sd) == SYSFS_KOBJ_LINK) |
Tejun Heo | b1fc3d6 | 2007-09-20 16:05:11 +0900 | [diff] [blame] | 277 | sysfs_put(sd->s_symlink.target_sd); |
Tejun Heo | b402d72 | 2007-06-14 04:27:21 +0900 | [diff] [blame] | 278 | if (sysfs_type(sd) & SYSFS_COPY_NAME) |
Tejun Heo | 0c096b5 | 2007-06-14 03:45:15 +0900 | [diff] [blame] | 279 | kfree(sd->s_name); |
Tejun Heo | fa7f912 | 2007-06-14 03:45:13 +0900 | [diff] [blame] | 280 | kfree(sd->s_iattr); |
Tejun Heo | 2b611bb | 2007-06-14 03:45:13 +0900 | [diff] [blame] | 281 | sysfs_free_ino(sd->s_ino); |
Tejun Heo | fa7f912 | 2007-06-14 03:45:13 +0900 | [diff] [blame] | 282 | kmem_cache_free(sysfs_dir_cachep, sd); |
Tejun Heo | 13b3086 | 2007-06-14 03:45:14 +0900 | [diff] [blame] | 283 | |
| 284 | sd = parent_sd; |
| 285 | if (sd && atomic_dec_and_test(&sd->s_count)) |
| 286 | goto repeat; |
Tejun Heo | fa7f912 | 2007-06-14 03:45:13 +0900 | [diff] [blame] | 287 | } |
| 288 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 289 | static void sysfs_d_iput(struct dentry * dentry, struct inode * inode) |
| 290 | { |
| 291 | struct sysfs_dirent * sd = dentry->d_fsdata; |
| 292 | |
Eric W. Biederman | 5a26b79 | 2007-08-20 21:36:30 +0900 | [diff] [blame] | 293 | sysfs_put(sd); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 294 | iput(inode); |
| 295 | } |
| 296 | |
| 297 | static struct dentry_operations sysfs_dentry_ops = { |
| 298 | .d_iput = sysfs_d_iput, |
| 299 | }; |
| 300 | |
Tejun Heo | 3e51903 | 2007-06-14 03:45:15 +0900 | [diff] [blame] | 301 | 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] | 302 | { |
Tejun Heo | 0c096b5 | 2007-06-14 03:45:15 +0900 | [diff] [blame] | 303 | char *dup_name = NULL; |
Akinobu Mita | 01da242 | 2007-07-14 11:03:35 +0900 | [diff] [blame] | 304 | struct sysfs_dirent *sd; |
Tejun Heo | 0c096b5 | 2007-06-14 03:45:15 +0900 | [diff] [blame] | 305 | |
| 306 | if (type & SYSFS_COPY_NAME) { |
| 307 | name = dup_name = kstrdup(name, GFP_KERNEL); |
| 308 | if (!name) |
Akinobu Mita | 01da242 | 2007-07-14 11:03:35 +0900 | [diff] [blame] | 309 | return NULL; |
Tejun Heo | 0c096b5 | 2007-06-14 03:45:15 +0900 | [diff] [blame] | 310 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 311 | |
Robert P. J. Day | c376222 | 2007-02-10 01:45:03 -0800 | [diff] [blame] | 312 | sd = kmem_cache_zalloc(sysfs_dir_cachep, GFP_KERNEL); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 313 | if (!sd) |
Akinobu Mita | 01da242 | 2007-07-14 11:03:35 +0900 | [diff] [blame] | 314 | goto err_out1; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 315 | |
Tejun Heo | 0c096b5 | 2007-06-14 03:45:15 +0900 | [diff] [blame] | 316 | if (sysfs_alloc_ino(&sd->s_ino)) |
Akinobu Mita | 01da242 | 2007-07-14 11:03:35 +0900 | [diff] [blame] | 317 | goto err_out2; |
Tejun Heo | 2b611bb | 2007-06-14 03:45:13 +0900 | [diff] [blame] | 318 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 319 | atomic_set(&sd->s_count, 1); |
Tejun Heo | 8619f97 | 2007-06-14 03:45:18 +0900 | [diff] [blame] | 320 | atomic_set(&sd->s_active, 0); |
Juha Yrjölä | eea3f89 | 2006-08-03 19:06:25 +0300 | [diff] [blame] | 321 | atomic_set(&sd->s_event, 1); |
Tejun Heo | a26cd72 | 2007-06-14 03:45:14 +0900 | [diff] [blame] | 322 | |
Tejun Heo | 0c096b5 | 2007-06-14 03:45:15 +0900 | [diff] [blame] | 323 | sd->s_name = name; |
Tejun Heo | a26cd72 | 2007-06-14 03:45:14 +0900 | [diff] [blame] | 324 | sd->s_mode = mode; |
Tejun Heo | b402d72 | 2007-06-14 04:27:21 +0900 | [diff] [blame] | 325 | sd->s_flags = type; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 326 | |
| 327 | return sd; |
Tejun Heo | 0c096b5 | 2007-06-14 03:45:15 +0900 | [diff] [blame] | 328 | |
Akinobu Mita | 01da242 | 2007-07-14 11:03:35 +0900 | [diff] [blame] | 329 | err_out2: |
Tejun Heo | 0c096b5 | 2007-06-14 03:45:15 +0900 | [diff] [blame] | 330 | kmem_cache_free(sysfs_dir_cachep, sd); |
Akinobu Mita | 01da242 | 2007-07-14 11:03:35 +0900 | [diff] [blame] | 331 | err_out1: |
| 332 | kfree(dup_name); |
Tejun Heo | 0c096b5 | 2007-06-14 03:45:15 +0900 | [diff] [blame] | 333 | return NULL; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 334 | } |
| 335 | |
Tejun Heo | fb6896da | 2007-06-14 04:27:24 +0900 | [diff] [blame] | 336 | static int sysfs_ilookup_test(struct inode *inode, void *arg) |
| 337 | { |
| 338 | struct sysfs_dirent *sd = arg; |
| 339 | return inode->i_ino == sd->s_ino; |
| 340 | } |
| 341 | |
Tejun Heo | 3007e99 | 2007-06-14 04:27:23 +0900 | [diff] [blame] | 342 | /** |
Tejun Heo | fb6896da | 2007-06-14 04:27:24 +0900 | [diff] [blame] | 343 | * sysfs_addrm_start - prepare for sysfs_dirent add/remove |
| 344 | * @acxt: pointer to sysfs_addrm_cxt to be used |
| 345 | * @parent_sd: parent sysfs_dirent |
Tejun Heo | 3007e99 | 2007-06-14 04:27:23 +0900 | [diff] [blame] | 346 | * |
Tejun Heo | fb6896da | 2007-06-14 04:27:24 +0900 | [diff] [blame] | 347 | * This function is called when the caller is about to add or |
| 348 | * remove sysfs_dirent under @parent_sd. This function acquires |
| 349 | * sysfs_mutex, grabs inode for @parent_sd if available and lock |
| 350 | * i_mutex of it. @acxt is used to keep and pass context to |
| 351 | * other addrm functions. |
Tejun Heo | 3007e99 | 2007-06-14 04:27:23 +0900 | [diff] [blame] | 352 | * |
| 353 | * LOCKING: |
Tejun Heo | fb6896da | 2007-06-14 04:27:24 +0900 | [diff] [blame] | 354 | * Kernel thread context (may sleep). sysfs_mutex is locked on |
| 355 | * return. i_mutex of parent inode is locked on return if |
| 356 | * available. |
Tejun Heo | 3007e99 | 2007-06-14 04:27:23 +0900 | [diff] [blame] | 357 | */ |
Tejun Heo | fb6896da | 2007-06-14 04:27:24 +0900 | [diff] [blame] | 358 | void sysfs_addrm_start(struct sysfs_addrm_cxt *acxt, |
| 359 | struct sysfs_dirent *parent_sd) |
Eric W. Biederman | b592fcf | 2007-01-24 12:35:52 -0700 | [diff] [blame] | 360 | { |
Tejun Heo | fb6896da | 2007-06-14 04:27:24 +0900 | [diff] [blame] | 361 | struct inode *inode; |
Tejun Heo | a26cd72 | 2007-06-14 03:45:14 +0900 | [diff] [blame] | 362 | |
Tejun Heo | fb6896da | 2007-06-14 04:27:24 +0900 | [diff] [blame] | 363 | memset(acxt, 0, sizeof(*acxt)); |
| 364 | acxt->parent_sd = parent_sd; |
| 365 | |
| 366 | /* Lookup parent inode. inode initialization and I_NEW |
| 367 | * clearing are protected by sysfs_mutex. By grabbing it and |
| 368 | * looking up with _nowait variant, inode state can be |
| 369 | * determined reliably. |
| 370 | */ |
| 371 | mutex_lock(&sysfs_mutex); |
| 372 | |
| 373 | inode = ilookup5_nowait(sysfs_sb, parent_sd->s_ino, sysfs_ilookup_test, |
| 374 | parent_sd); |
| 375 | |
| 376 | if (inode && !(inode->i_state & I_NEW)) { |
| 377 | /* parent inode available */ |
| 378 | acxt->parent_inode = inode; |
| 379 | |
| 380 | /* sysfs_mutex is below i_mutex in lock hierarchy. |
| 381 | * First, trylock i_mutex. If fails, unlock |
| 382 | * sysfs_mutex and lock them in order. |
| 383 | */ |
| 384 | if (!mutex_trylock(&inode->i_mutex)) { |
| 385 | mutex_unlock(&sysfs_mutex); |
| 386 | mutex_lock(&inode->i_mutex); |
| 387 | mutex_lock(&sysfs_mutex); |
| 388 | } |
| 389 | } else |
| 390 | iput(inode); |
| 391 | } |
| 392 | |
| 393 | /** |
| 394 | * sysfs_add_one - add sysfs_dirent to parent |
| 395 | * @acxt: addrm context to use |
| 396 | * @sd: sysfs_dirent to be added |
| 397 | * |
| 398 | * Get @acxt->parent_sd and set sd->s_parent to it and increment |
Tejun Heo | 181b2e4 | 2007-09-20 16:05:09 +0900 | [diff] [blame] | 399 | * nlink of parent inode if @sd is a directory and link into the |
| 400 | * children list of the parent. |
Tejun Heo | fb6896da | 2007-06-14 04:27:24 +0900 | [diff] [blame] | 401 | * |
| 402 | * This function should be called between calls to |
| 403 | * sysfs_addrm_start() and sysfs_addrm_finish() and should be |
| 404 | * passed the same @acxt as passed to sysfs_addrm_start(). |
| 405 | * |
| 406 | * LOCKING: |
| 407 | * Determined by sysfs_addrm_start(). |
Tejun Heo | 23dc279 | 2007-08-02 21:38:03 +0900 | [diff] [blame] | 408 | * |
| 409 | * RETURNS: |
| 410 | * 0 on success, -EEXIST if entry with the given name already |
| 411 | * exists. |
Tejun Heo | fb6896da | 2007-06-14 04:27:24 +0900 | [diff] [blame] | 412 | */ |
Tejun Heo | 23dc279 | 2007-08-02 21:38:03 +0900 | [diff] [blame] | 413 | int sysfs_add_one(struct sysfs_addrm_cxt *acxt, struct sysfs_dirent *sd) |
Tejun Heo | fb6896da | 2007-06-14 04:27:24 +0900 | [diff] [blame] | 414 | { |
Greg Kroah-Hartman | 5c3e896 | 2007-09-13 02:53:13 -0700 | [diff] [blame] | 415 | if (sysfs_find_dirent(acxt->parent_sd, sd->s_name)) { |
| 416 | printk(KERN_WARNING "sysfs: duplicate filename '%s' " |
| 417 | "can not be created\n", sd->s_name); |
| 418 | WARN_ON(1); |
Tejun Heo | 23dc279 | 2007-08-02 21:38:03 +0900 | [diff] [blame] | 419 | return -EEXIST; |
Greg Kroah-Hartman | 5c3e896 | 2007-09-13 02:53:13 -0700 | [diff] [blame] | 420 | } |
Tejun Heo | 23dc279 | 2007-08-02 21:38:03 +0900 | [diff] [blame] | 421 | |
Tejun Heo | fb6896da | 2007-06-14 04:27:24 +0900 | [diff] [blame] | 422 | sd->s_parent = sysfs_get(acxt->parent_sd); |
| 423 | |
| 424 | if (sysfs_type(sd) == SYSFS_DIR && acxt->parent_inode) |
| 425 | inc_nlink(acxt->parent_inode); |
| 426 | |
| 427 | acxt->cnt++; |
Tejun Heo | 41fc1c2 | 2007-08-02 21:38:03 +0900 | [diff] [blame] | 428 | |
| 429 | sysfs_link_sibling(sd); |
Tejun Heo | 23dc279 | 2007-08-02 21:38:03 +0900 | [diff] [blame] | 430 | |
| 431 | return 0; |
Tejun Heo | fb6896da | 2007-06-14 04:27:24 +0900 | [diff] [blame] | 432 | } |
| 433 | |
| 434 | /** |
| 435 | * sysfs_remove_one - remove sysfs_dirent from parent |
| 436 | * @acxt: addrm context to use |
| 437 | * @sd: sysfs_dirent to be added |
| 438 | * |
| 439 | * Mark @sd removed and drop nlink of parent inode if @sd is a |
Tejun Heo | 181b2e4 | 2007-09-20 16:05:09 +0900 | [diff] [blame] | 440 | * directory. @sd is unlinked from the children list. |
Tejun Heo | fb6896da | 2007-06-14 04:27:24 +0900 | [diff] [blame] | 441 | * |
| 442 | * This function should be called between calls to |
| 443 | * sysfs_addrm_start() and sysfs_addrm_finish() and should be |
| 444 | * passed the same @acxt as passed to sysfs_addrm_start(). |
| 445 | * |
| 446 | * LOCKING: |
| 447 | * Determined by sysfs_addrm_start(). |
| 448 | */ |
| 449 | void sysfs_remove_one(struct sysfs_addrm_cxt *acxt, struct sysfs_dirent *sd) |
| 450 | { |
Tejun Heo | 41fc1c2 | 2007-08-02 21:38:03 +0900 | [diff] [blame] | 451 | BUG_ON(sd->s_flags & SYSFS_FLAG_REMOVED); |
| 452 | |
| 453 | sysfs_unlink_sibling(sd); |
Tejun Heo | fb6896da | 2007-06-14 04:27:24 +0900 | [diff] [blame] | 454 | |
| 455 | sd->s_flags |= SYSFS_FLAG_REMOVED; |
| 456 | sd->s_sibling = acxt->removed; |
| 457 | acxt->removed = sd; |
| 458 | |
| 459 | if (sysfs_type(sd) == SYSFS_DIR && acxt->parent_inode) |
| 460 | drop_nlink(acxt->parent_inode); |
| 461 | |
| 462 | acxt->cnt++; |
| 463 | } |
| 464 | |
| 465 | /** |
Tejun Heo | a0edd7c | 2007-06-14 04:27:24 +0900 | [diff] [blame] | 466 | * sysfs_drop_dentry - drop dentry for the specified sysfs_dirent |
| 467 | * @sd: target sysfs_dirent |
| 468 | * |
| 469 | * Drop dentry for @sd. @sd must have been unlinked from its |
| 470 | * parent on entry to this function such that it can't be looked |
| 471 | * up anymore. |
Tejun Heo | a0edd7c | 2007-06-14 04:27:24 +0900 | [diff] [blame] | 472 | */ |
| 473 | static void sysfs_drop_dentry(struct sysfs_dirent *sd) |
| 474 | { |
Tejun Heo | a0edd7c | 2007-06-14 04:27:24 +0900 | [diff] [blame] | 475 | struct inode *inode; |
Eric W. Biederman | 89bec09 | 2007-08-20 21:36:30 +0900 | [diff] [blame] | 476 | struct dentry *dentry; |
Tejun Heo | a0edd7c | 2007-06-14 04:27:24 +0900 | [diff] [blame] | 477 | |
Eric W. Biederman | 89bec09 | 2007-08-20 21:36:30 +0900 | [diff] [blame] | 478 | inode = ilookup(sysfs_sb, sd->s_ino); |
| 479 | if (!inode) |
| 480 | return; |
| 481 | |
| 482 | /* Drop any existing dentries associated with sd. |
| 483 | * |
| 484 | * For the dentry to be properly freed we need to grab a |
| 485 | * reference to the dentry under the dcache lock, unhash it, |
| 486 | * and then put it. The playing with the dentry count allows |
| 487 | * dput to immediately free the dentry if it is not in use. |
Tejun Heo | a0edd7c | 2007-06-14 04:27:24 +0900 | [diff] [blame] | 488 | */ |
Eric W. Biederman | 89bec09 | 2007-08-20 21:36:30 +0900 | [diff] [blame] | 489 | repeat: |
Tejun Heo | a0edd7c | 2007-06-14 04:27:24 +0900 | [diff] [blame] | 490 | spin_lock(&dcache_lock); |
Eric W. Biederman | 89bec09 | 2007-08-20 21:36:30 +0900 | [diff] [blame] | 491 | list_for_each_entry(dentry, &inode->i_dentry, d_alias) { |
| 492 | if (d_unhashed(dentry)) |
| 493 | continue; |
| 494 | dget_locked(dentry); |
Tejun Heo | a0edd7c | 2007-06-14 04:27:24 +0900 | [diff] [blame] | 495 | spin_lock(&dentry->d_lock); |
| 496 | __d_drop(dentry); |
| 497 | spin_unlock(&dentry->d_lock); |
Eric W. Biederman | 89bec09 | 2007-08-20 21:36:30 +0900 | [diff] [blame] | 498 | spin_unlock(&dcache_lock); |
| 499 | dput(dentry); |
| 500 | goto repeat; |
Tejun Heo | a0edd7c | 2007-06-14 04:27:24 +0900 | [diff] [blame] | 501 | } |
Tejun Heo | a0edd7c | 2007-06-14 04:27:24 +0900 | [diff] [blame] | 502 | spin_unlock(&dcache_lock); |
Tejun Heo | a0edd7c | 2007-06-14 04:27:24 +0900 | [diff] [blame] | 503 | |
| 504 | /* adjust nlink and update timestamp */ |
Eric W. Biederman | 89bec09 | 2007-08-20 21:36:30 +0900 | [diff] [blame] | 505 | mutex_lock(&inode->i_mutex); |
Tejun Heo | a0edd7c | 2007-06-14 04:27:24 +0900 | [diff] [blame] | 506 | |
Eric W. Biederman | 89bec09 | 2007-08-20 21:36:30 +0900 | [diff] [blame] | 507 | inode->i_ctime = CURRENT_TIME; |
| 508 | drop_nlink(inode); |
| 509 | if (sysfs_type(sd) == SYSFS_DIR) |
Tejun Heo | a0edd7c | 2007-06-14 04:27:24 +0900 | [diff] [blame] | 510 | drop_nlink(inode); |
Tejun Heo | a0edd7c | 2007-06-14 04:27:24 +0900 | [diff] [blame] | 511 | |
Eric W. Biederman | 89bec09 | 2007-08-20 21:36:30 +0900 | [diff] [blame] | 512 | mutex_unlock(&inode->i_mutex); |
| 513 | |
| 514 | iput(inode); |
Tejun Heo | a0edd7c | 2007-06-14 04:27:24 +0900 | [diff] [blame] | 515 | } |
| 516 | |
| 517 | /** |
Tejun Heo | fb6896da | 2007-06-14 04:27:24 +0900 | [diff] [blame] | 518 | * sysfs_addrm_finish - finish up sysfs_dirent add/remove |
| 519 | * @acxt: addrm context to finish up |
| 520 | * |
| 521 | * Finish up sysfs_dirent add/remove. Resources acquired by |
| 522 | * sysfs_addrm_start() are released and removed sysfs_dirents are |
| 523 | * cleaned up. Timestamps on the parent inode are updated. |
| 524 | * |
| 525 | * LOCKING: |
| 526 | * All mutexes acquired by sysfs_addrm_start() are released. |
Tejun Heo | fb6896da | 2007-06-14 04:27:24 +0900 | [diff] [blame] | 527 | */ |
Tejun Heo | 990e53f | 2007-08-02 21:38:03 +0900 | [diff] [blame] | 528 | void sysfs_addrm_finish(struct sysfs_addrm_cxt *acxt) |
Tejun Heo | fb6896da | 2007-06-14 04:27:24 +0900 | [diff] [blame] | 529 | { |
| 530 | /* release resources acquired by sysfs_addrm_start() */ |
| 531 | mutex_unlock(&sysfs_mutex); |
| 532 | if (acxt->parent_inode) { |
| 533 | struct inode *inode = acxt->parent_inode; |
| 534 | |
| 535 | /* if added/removed, update timestamps on the parent */ |
| 536 | if (acxt->cnt) |
| 537 | inode->i_ctime = inode->i_mtime = CURRENT_TIME; |
| 538 | |
| 539 | mutex_unlock(&inode->i_mutex); |
| 540 | iput(inode); |
Tejun Heo | 13b3086 | 2007-06-14 03:45:14 +0900 | [diff] [blame] | 541 | } |
Tejun Heo | fb6896da | 2007-06-14 04:27:24 +0900 | [diff] [blame] | 542 | |
| 543 | /* kill removed sysfs_dirents */ |
| 544 | while (acxt->removed) { |
| 545 | struct sysfs_dirent *sd = acxt->removed; |
| 546 | |
| 547 | acxt->removed = sd->s_sibling; |
| 548 | sd->s_sibling = NULL; |
| 549 | |
| 550 | sysfs_drop_dentry(sd); |
| 551 | sysfs_deactivate(sd); |
| 552 | sysfs_put(sd); |
| 553 | } |
Eric W. Biederman | b592fcf | 2007-01-24 12:35:52 -0700 | [diff] [blame] | 554 | } |
| 555 | |
Tejun Heo | f0b0af4 | 2007-06-14 04:27:22 +0900 | [diff] [blame] | 556 | /** |
| 557 | * sysfs_find_dirent - find sysfs_dirent with the given name |
| 558 | * @parent_sd: sysfs_dirent to search under |
| 559 | * @name: name to look for |
Maneesh Soni | c516865 | 2006-03-09 19:40:14 +0530 | [diff] [blame] | 560 | * |
Tejun Heo | f0b0af4 | 2007-06-14 04:27:22 +0900 | [diff] [blame] | 561 | * Look for sysfs_dirent with name @name under @parent_sd. |
Maneesh Soni | c516865 | 2006-03-09 19:40:14 +0530 | [diff] [blame] | 562 | * |
Tejun Heo | f0b0af4 | 2007-06-14 04:27:22 +0900 | [diff] [blame] | 563 | * LOCKING: |
Tejun Heo | 3007e99 | 2007-06-14 04:27:23 +0900 | [diff] [blame] | 564 | * mutex_lock(sysfs_mutex) |
Tejun Heo | f0b0af4 | 2007-06-14 04:27:22 +0900 | [diff] [blame] | 565 | * |
| 566 | * RETURNS: |
| 567 | * Pointer to sysfs_dirent if found, NULL if not. |
Maneesh Soni | c516865 | 2006-03-09 19:40:14 +0530 | [diff] [blame] | 568 | */ |
Tejun Heo | f0b0af4 | 2007-06-14 04:27:22 +0900 | [diff] [blame] | 569 | struct sysfs_dirent *sysfs_find_dirent(struct sysfs_dirent *parent_sd, |
| 570 | const unsigned char *name) |
Maneesh Soni | c516865 | 2006-03-09 19:40:14 +0530 | [diff] [blame] | 571 | { |
Tejun Heo | f0b0af4 | 2007-06-14 04:27:22 +0900 | [diff] [blame] | 572 | struct sysfs_dirent *sd; |
Maneesh Soni | c516865 | 2006-03-09 19:40:14 +0530 | [diff] [blame] | 573 | |
Tejun Heo | bc747f3 | 2007-09-20 16:05:12 +0900 | [diff] [blame^] | 574 | for (sd = parent_sd->s_dir.children; sd; sd = sd->s_sibling) |
Eric W. Biederman | 3efa65b | 2007-08-20 21:36:30 +0900 | [diff] [blame] | 575 | if (!strcmp(sd->s_name, name)) |
Tejun Heo | f0b0af4 | 2007-06-14 04:27:22 +0900 | [diff] [blame] | 576 | return sd; |
| 577 | return NULL; |
| 578 | } |
Maneesh Soni | c516865 | 2006-03-09 19:40:14 +0530 | [diff] [blame] | 579 | |
Tejun Heo | f0b0af4 | 2007-06-14 04:27:22 +0900 | [diff] [blame] | 580 | /** |
| 581 | * sysfs_get_dirent - find and get sysfs_dirent with the given name |
| 582 | * @parent_sd: sysfs_dirent to search under |
| 583 | * @name: name to look for |
| 584 | * |
| 585 | * Look for sysfs_dirent with name @name under @parent_sd and get |
| 586 | * it if found. |
| 587 | * |
| 588 | * LOCKING: |
Tejun Heo | 3007e99 | 2007-06-14 04:27:23 +0900 | [diff] [blame] | 589 | * Kernel thread context (may sleep). Grabs sysfs_mutex. |
Tejun Heo | f0b0af4 | 2007-06-14 04:27:22 +0900 | [diff] [blame] | 590 | * |
| 591 | * RETURNS: |
| 592 | * Pointer to sysfs_dirent if found, NULL if not. |
| 593 | */ |
| 594 | struct sysfs_dirent *sysfs_get_dirent(struct sysfs_dirent *parent_sd, |
| 595 | const unsigned char *name) |
| 596 | { |
| 597 | struct sysfs_dirent *sd; |
| 598 | |
Tejun Heo | 3007e99 | 2007-06-14 04:27:23 +0900 | [diff] [blame] | 599 | mutex_lock(&sysfs_mutex); |
Tejun Heo | f0b0af4 | 2007-06-14 04:27:22 +0900 | [diff] [blame] | 600 | sd = sysfs_find_dirent(parent_sd, name); |
| 601 | sysfs_get(sd); |
Tejun Heo | 3007e99 | 2007-06-14 04:27:23 +0900 | [diff] [blame] | 602 | mutex_unlock(&sysfs_mutex); |
Tejun Heo | f0b0af4 | 2007-06-14 04:27:22 +0900 | [diff] [blame] | 603 | |
| 604 | return sd; |
Maneesh Soni | c516865 | 2006-03-09 19:40:14 +0530 | [diff] [blame] | 605 | } |
| 606 | |
Tejun Heo | 608e266 | 2007-06-14 04:27:22 +0900 | [diff] [blame] | 607 | static int create_dir(struct kobject *kobj, struct sysfs_dirent *parent_sd, |
| 608 | const char *name, struct sysfs_dirent **p_sd) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 609 | { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 610 | umode_t mode = S_IFDIR| S_IRWXU | S_IRUGO | S_IXUGO; |
Tejun Heo | 5122503 | 2007-06-14 04:27:25 +0900 | [diff] [blame] | 611 | struct sysfs_addrm_cxt acxt; |
Tejun Heo | dfeb9fb | 2007-06-14 03:45:14 +0900 | [diff] [blame] | 612 | struct sysfs_dirent *sd; |
Tejun Heo | 23dc279 | 2007-08-02 21:38:03 +0900 | [diff] [blame] | 613 | int rc; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 614 | |
Tejun Heo | fc9f54b | 2007-06-14 03:45:17 +0900 | [diff] [blame] | 615 | /* allocate */ |
Tejun Heo | 3e51903 | 2007-06-14 03:45:15 +0900 | [diff] [blame] | 616 | sd = sysfs_new_dirent(name, mode, SYSFS_DIR); |
Tejun Heo | a26cd72 | 2007-06-14 03:45:14 +0900 | [diff] [blame] | 617 | if (!sd) |
Tejun Heo | 5122503 | 2007-06-14 04:27:25 +0900 | [diff] [blame] | 618 | return -ENOMEM; |
Tejun Heo | b1fc3d6 | 2007-09-20 16:05:11 +0900 | [diff] [blame] | 619 | sd->s_dir.kobj = kobj; |
Tejun Heo | dfeb9fb | 2007-06-14 03:45:14 +0900 | [diff] [blame] | 620 | |
Tejun Heo | 5122503 | 2007-06-14 04:27:25 +0900 | [diff] [blame] | 621 | /* link in */ |
| 622 | sysfs_addrm_start(&acxt, parent_sd); |
Tejun Heo | 23dc279 | 2007-08-02 21:38:03 +0900 | [diff] [blame] | 623 | rc = sysfs_add_one(&acxt, sd); |
| 624 | sysfs_addrm_finish(&acxt); |
Tejun Heo | 967e35d | 2007-07-18 16:38:11 +0900 | [diff] [blame] | 625 | |
Tejun Heo | 23dc279 | 2007-08-02 21:38:03 +0900 | [diff] [blame] | 626 | if (rc == 0) |
| 627 | *p_sd = sd; |
| 628 | else |
Tejun Heo | 967e35d | 2007-07-18 16:38:11 +0900 | [diff] [blame] | 629 | sysfs_put(sd); |
Tejun Heo | fc9f54b | 2007-06-14 03:45:17 +0900 | [diff] [blame] | 630 | |
Tejun Heo | 23dc279 | 2007-08-02 21:38:03 +0900 | [diff] [blame] | 631 | return rc; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 632 | } |
| 633 | |
Tejun Heo | 608e266 | 2007-06-14 04:27:22 +0900 | [diff] [blame] | 634 | int sysfs_create_subdir(struct kobject *kobj, const char *name, |
| 635 | struct sysfs_dirent **p_sd) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 636 | { |
Tejun Heo | 608e266 | 2007-06-14 04:27:22 +0900 | [diff] [blame] | 637 | return create_dir(kobj, kobj->sd, name, p_sd); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 638 | } |
| 639 | |
| 640 | /** |
| 641 | * sysfs_create_dir - create a directory for an object. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 642 | * @kobj: object we're creating directory for. |
| 643 | */ |
Eric W. Biederman | 90bc613 | 2007-07-31 19:15:08 +0900 | [diff] [blame] | 644 | int sysfs_create_dir(struct kobject * kobj) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 645 | { |
Tejun Heo | 608e266 | 2007-06-14 04:27:22 +0900 | [diff] [blame] | 646 | struct sysfs_dirent *parent_sd, *sd; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 647 | int error = 0; |
| 648 | |
| 649 | BUG_ON(!kobj); |
| 650 | |
Eric W. Biederman | 90bc613 | 2007-07-31 19:15:08 +0900 | [diff] [blame] | 651 | if (kobj->parent) |
Tejun Heo | 608e266 | 2007-06-14 04:27:22 +0900 | [diff] [blame] | 652 | parent_sd = kobj->parent->sd; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 653 | else |
Eric W. Biederman | 7d0c7d6 | 2007-08-20 21:36:30 +0900 | [diff] [blame] | 654 | parent_sd = &sysfs_root; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 655 | |
Tejun Heo | 608e266 | 2007-06-14 04:27:22 +0900 | [diff] [blame] | 656 | error = create_dir(kobj, parent_sd, kobject_name(kobj), &sd); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 657 | if (!error) |
Tejun Heo | 608e266 | 2007-06-14 04:27:22 +0900 | [diff] [blame] | 658 | kobj->sd = sd; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 659 | return error; |
| 660 | } |
| 661 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 662 | static struct dentry * sysfs_lookup(struct inode *dir, struct dentry *dentry, |
| 663 | struct nameidata *nd) |
| 664 | { |
Tejun Heo | 6cb5214 | 2007-07-31 19:15:08 +0900 | [diff] [blame] | 665 | struct dentry *ret = NULL; |
Tejun Heo | a7a0475 | 2007-08-02 21:38:02 +0900 | [diff] [blame] | 666 | struct sysfs_dirent *parent_sd = dentry->d_parent->d_fsdata; |
| 667 | struct sysfs_dirent *sd; |
Tejun Heo | fc9f54b | 2007-06-14 03:45:17 +0900 | [diff] [blame] | 668 | struct inode *inode; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 669 | |
Tejun Heo | 6cb5214 | 2007-07-31 19:15:08 +0900 | [diff] [blame] | 670 | mutex_lock(&sysfs_mutex); |
| 671 | |
Eric W. Biederman | 94777e0 | 2007-08-20 21:36:30 +0900 | [diff] [blame] | 672 | sd = sysfs_find_dirent(parent_sd, dentry->d_name.name); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 673 | |
Tejun Heo | fc9f54b | 2007-06-14 03:45:17 +0900 | [diff] [blame] | 674 | /* no such entry */ |
Tejun Heo | a7a0475 | 2007-08-02 21:38:02 +0900 | [diff] [blame] | 675 | if (!sd) |
Tejun Heo | 6cb5214 | 2007-07-31 19:15:08 +0900 | [diff] [blame] | 676 | goto out_unlock; |
Tejun Heo | fc9f54b | 2007-06-14 03:45:17 +0900 | [diff] [blame] | 677 | |
| 678 | /* attach dentry and inode */ |
Tejun Heo | 8312a8d | 2007-06-14 03:45:17 +0900 | [diff] [blame] | 679 | inode = sysfs_get_inode(sd); |
Tejun Heo | 6cb5214 | 2007-07-31 19:15:08 +0900 | [diff] [blame] | 680 | if (!inode) { |
| 681 | ret = ERR_PTR(-ENOMEM); |
| 682 | goto out_unlock; |
| 683 | } |
Tejun Heo | 3007e99 | 2007-06-14 04:27:23 +0900 | [diff] [blame] | 684 | |
Tejun Heo | d6b4fd2 | 2007-09-20 16:05:11 +0900 | [diff] [blame] | 685 | /* instantiate and hash dentry */ |
| 686 | dentry->d_op = &sysfs_dentry_ops; |
| 687 | dentry->d_fsdata = sysfs_get(sd); |
Eric W. Biederman | 119dd52 | 2007-08-20 21:36:29 +0900 | [diff] [blame] | 688 | d_instantiate(dentry, inode); |
Tejun Heo | d6b4fd2 | 2007-09-20 16:05:11 +0900 | [diff] [blame] | 689 | d_rehash(dentry); |
Tejun Heo | fc9f54b | 2007-06-14 03:45:17 +0900 | [diff] [blame] | 690 | |
Tejun Heo | 6cb5214 | 2007-07-31 19:15:08 +0900 | [diff] [blame] | 691 | out_unlock: |
Tejun Heo | 3007e99 | 2007-06-14 04:27:23 +0900 | [diff] [blame] | 692 | mutex_unlock(&sysfs_mutex); |
Tejun Heo | 6cb5214 | 2007-07-31 19:15:08 +0900 | [diff] [blame] | 693 | return ret; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 694 | } |
| 695 | |
Arjan van de Ven | c5ef1c4 | 2007-02-12 00:55:40 -0800 | [diff] [blame] | 696 | const struct inode_operations sysfs_dir_inode_operations = { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 697 | .lookup = sysfs_lookup, |
Maneesh Soni | 988d186 | 2005-05-31 10:39:14 +0530 | [diff] [blame] | 698 | .setattr = sysfs_setattr, |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 699 | }; |
| 700 | |
Tejun Heo | 608e266 | 2007-06-14 04:27:22 +0900 | [diff] [blame] | 701 | static void remove_dir(struct sysfs_dirent *sd) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 702 | { |
Tejun Heo | fb6896da | 2007-06-14 04:27:24 +0900 | [diff] [blame] | 703 | struct sysfs_addrm_cxt acxt; |
| 704 | |
| 705 | sysfs_addrm_start(&acxt, sd->s_parent); |
Tejun Heo | fb6896da | 2007-06-14 04:27:24 +0900 | [diff] [blame] | 706 | sysfs_remove_one(&acxt, sd); |
| 707 | sysfs_addrm_finish(&acxt); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 708 | } |
| 709 | |
Tejun Heo | 608e266 | 2007-06-14 04:27:22 +0900 | [diff] [blame] | 710 | void sysfs_remove_subdir(struct sysfs_dirent *sd) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 711 | { |
Tejun Heo | 608e266 | 2007-06-14 04:27:22 +0900 | [diff] [blame] | 712 | remove_dir(sd); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 713 | } |
| 714 | |
| 715 | |
Tejun Heo | 608e266 | 2007-06-14 04:27:22 +0900 | [diff] [blame] | 716 | static void __sysfs_remove_dir(struct sysfs_dirent *dir_sd) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 717 | { |
Tejun Heo | fb6896da | 2007-06-14 04:27:24 +0900 | [diff] [blame] | 718 | struct sysfs_addrm_cxt acxt; |
Tejun Heo | 0c73f18 | 2007-06-14 03:45:18 +0900 | [diff] [blame] | 719 | struct sysfs_dirent **pos; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 720 | |
Tejun Heo | 608e266 | 2007-06-14 04:27:22 +0900 | [diff] [blame] | 721 | if (!dir_sd) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 722 | return; |
| 723 | |
Tejun Heo | 608e266 | 2007-06-14 04:27:22 +0900 | [diff] [blame] | 724 | pr_debug("sysfs %s: removing dir\n", dir_sd->s_name); |
Tejun Heo | fb6896da | 2007-06-14 04:27:24 +0900 | [diff] [blame] | 725 | sysfs_addrm_start(&acxt, dir_sd); |
Tejun Heo | bc747f3 | 2007-09-20 16:05:12 +0900 | [diff] [blame^] | 726 | pos = &dir_sd->s_dir.children; |
Tejun Heo | 0c73f18 | 2007-06-14 03:45:18 +0900 | [diff] [blame] | 727 | while (*pos) { |
| 728 | struct sysfs_dirent *sd = *pos; |
| 729 | |
Eric W. Biederman | 3efa65b | 2007-08-20 21:36:30 +0900 | [diff] [blame] | 730 | if (sysfs_type(sd) != SYSFS_DIR) |
Tejun Heo | fb6896da | 2007-06-14 04:27:24 +0900 | [diff] [blame] | 731 | sysfs_remove_one(&acxt, sd); |
Tejun Heo | 41fc1c2 | 2007-08-02 21:38:03 +0900 | [diff] [blame] | 732 | else |
Tejun Heo | 0c73f18 | 2007-06-14 03:45:18 +0900 | [diff] [blame] | 733 | pos = &(*pos)->s_sibling; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 734 | } |
Tejun Heo | fb6896da | 2007-06-14 04:27:24 +0900 | [diff] [blame] | 735 | sysfs_addrm_finish(&acxt); |
Tejun Heo | 0ab6608 | 2007-06-14 03:45:16 +0900 | [diff] [blame] | 736 | |
Tejun Heo | 608e266 | 2007-06-14 04:27:22 +0900 | [diff] [blame] | 737 | remove_dir(dir_sd); |
Eric W. Biederman | b592fcf | 2007-01-24 12:35:52 -0700 | [diff] [blame] | 738 | } |
| 739 | |
| 740 | /** |
| 741 | * sysfs_remove_dir - remove an object's directory. |
| 742 | * @kobj: object. |
| 743 | * |
| 744 | * The only thing special about this is that we remove any files in |
| 745 | * the directory before we remove the directory, and we've inlined |
| 746 | * what used to be sysfs_rmdir() below, instead of calling separately. |
| 747 | */ |
| 748 | |
| 749 | void sysfs_remove_dir(struct kobject * kobj) |
| 750 | { |
Tejun Heo | 608e266 | 2007-06-14 04:27:22 +0900 | [diff] [blame] | 751 | struct sysfs_dirent *sd = kobj->sd; |
Tejun Heo | aecdced | 2007-06-14 03:45:15 +0900 | [diff] [blame] | 752 | |
Tejun Heo | 5f99532 | 2007-06-14 04:27:23 +0900 | [diff] [blame] | 753 | spin_lock(&sysfs_assoc_lock); |
Tejun Heo | 608e266 | 2007-06-14 04:27:22 +0900 | [diff] [blame] | 754 | kobj->sd = NULL; |
Tejun Heo | 5f99532 | 2007-06-14 04:27:23 +0900 | [diff] [blame] | 755 | spin_unlock(&sysfs_assoc_lock); |
Tejun Heo | aecdced | 2007-06-14 03:45:15 +0900 | [diff] [blame] | 756 | |
Tejun Heo | 608e266 | 2007-06-14 04:27:22 +0900 | [diff] [blame] | 757 | __sysfs_remove_dir(sd); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 758 | } |
| 759 | |
Eric W. Biederman | 90bc613 | 2007-07-31 19:15:08 +0900 | [diff] [blame] | 760 | int sysfs_rename_dir(struct kobject * kobj, const char *new_name) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 761 | { |
Eric W. Biederman | 9918f9a | 2007-08-20 21:36:31 +0900 | [diff] [blame] | 762 | struct sysfs_dirent *sd = kobj->sd; |
Eric W. Biederman | 90bc613 | 2007-07-31 19:15:08 +0900 | [diff] [blame] | 763 | struct dentry *parent = NULL; |
Tejun Heo | 5122503 | 2007-06-14 04:27:25 +0900 | [diff] [blame] | 764 | struct dentry *old_dentry = NULL, *new_dentry = NULL; |
| 765 | const char *dup_name = NULL; |
Tejun Heo | 996b737 | 2007-06-14 03:45:14 +0900 | [diff] [blame] | 766 | int error; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 767 | |
Eric W. Biederman | 932ea2e | 2007-08-20 21:36:30 +0900 | [diff] [blame] | 768 | mutex_lock(&sysfs_rename_mutex); |
| 769 | |
Eric W. Biederman | 9918f9a | 2007-08-20 21:36:31 +0900 | [diff] [blame] | 770 | error = 0; |
| 771 | if (strcmp(sd->s_name, new_name) == 0) |
| 772 | goto out; /* nothing to rename */ |
| 773 | |
Tejun Heo | ff869de | 2007-08-02 21:38:02 +0900 | [diff] [blame] | 774 | /* get the original dentry */ |
Tejun Heo | 5122503 | 2007-06-14 04:27:25 +0900 | [diff] [blame] | 775 | old_dentry = sysfs_get_dentry(sd); |
| 776 | if (IS_ERR(old_dentry)) { |
| 777 | error = PTR_ERR(old_dentry); |
Eric W. Biederman | 9918f9a | 2007-08-20 21:36:31 +0900 | [diff] [blame] | 778 | goto out; |
Tejun Heo | 5122503 | 2007-06-14 04:27:25 +0900 | [diff] [blame] | 779 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 780 | |
Tejun Heo | ff869de | 2007-08-02 21:38:02 +0900 | [diff] [blame] | 781 | parent = old_dentry->d_parent; |
Tejun Heo | 5122503 | 2007-06-14 04:27:25 +0900 | [diff] [blame] | 782 | |
Eric W. Biederman | 90bc613 | 2007-07-31 19:15:08 +0900 | [diff] [blame] | 783 | /* lock parent and get dentry for new name */ |
| 784 | mutex_lock(&parent->d_inode->i_mutex); |
Eric W. Biederman | 9918f9a | 2007-08-20 21:36:31 +0900 | [diff] [blame] | 785 | mutex_lock(&sysfs_mutex); |
Tejun Heo | 996b737 | 2007-06-14 03:45:14 +0900 | [diff] [blame] | 786 | |
| 787 | error = -EEXIST; |
Eric W. Biederman | 9918f9a | 2007-08-20 21:36:31 +0900 | [diff] [blame] | 788 | if (sysfs_find_dirent(sd->s_parent, new_name)) |
| 789 | goto out_unlock; |
| 790 | |
| 791 | error = -ENOMEM; |
| 792 | new_dentry = d_alloc_name(parent, new_name); |
| 793 | if (!new_dentry) |
Tejun Heo | 5122503 | 2007-06-14 04:27:25 +0900 | [diff] [blame] | 794 | goto out_unlock; |
Tejun Heo | 996b737 | 2007-06-14 03:45:14 +0900 | [diff] [blame] | 795 | |
Tejun Heo | 0c096b5 | 2007-06-14 03:45:15 +0900 | [diff] [blame] | 796 | /* rename kobject and sysfs_dirent */ |
| 797 | error = -ENOMEM; |
| 798 | new_name = dup_name = kstrdup(new_name, GFP_KERNEL); |
| 799 | if (!new_name) |
Eric W. Biederman | 9918f9a | 2007-08-20 21:36:31 +0900 | [diff] [blame] | 800 | goto out_unlock; |
Tejun Heo | 996b737 | 2007-06-14 03:45:14 +0900 | [diff] [blame] | 801 | |
Tejun Heo | 0c096b5 | 2007-06-14 03:45:15 +0900 | [diff] [blame] | 802 | error = kobject_set_name(kobj, "%s", new_name); |
| 803 | if (error) |
Eric W. Biederman | 9918f9a | 2007-08-20 21:36:31 +0900 | [diff] [blame] | 804 | goto out_unlock; |
Tejun Heo | 0c096b5 | 2007-06-14 03:45:15 +0900 | [diff] [blame] | 805 | |
Tejun Heo | 5122503 | 2007-06-14 04:27:25 +0900 | [diff] [blame] | 806 | dup_name = sd->s_name; |
Tejun Heo | 0c096b5 | 2007-06-14 03:45:15 +0900 | [diff] [blame] | 807 | sd->s_name = new_name; |
| 808 | |
Tejun Heo | ff869de | 2007-08-02 21:38:02 +0900 | [diff] [blame] | 809 | /* rename */ |
Tejun Heo | 996b737 | 2007-06-14 03:45:14 +0900 | [diff] [blame] | 810 | d_add(new_dentry, NULL); |
Eric W. Biederman | 5a26b79 | 2007-08-20 21:36:30 +0900 | [diff] [blame] | 811 | d_move(old_dentry, new_dentry); |
Tejun Heo | 996b737 | 2007-06-14 03:45:14 +0900 | [diff] [blame] | 812 | |
Tejun Heo | 996b737 | 2007-06-14 03:45:14 +0900 | [diff] [blame] | 813 | error = 0; |
Tejun Heo | 996b737 | 2007-06-14 03:45:14 +0900 | [diff] [blame] | 814 | out_unlock: |
Eric W. Biederman | 9918f9a | 2007-08-20 21:36:31 +0900 | [diff] [blame] | 815 | mutex_unlock(&sysfs_mutex); |
Eric W. Biederman | 90bc613 | 2007-07-31 19:15:08 +0900 | [diff] [blame] | 816 | mutex_unlock(&parent->d_inode->i_mutex); |
Tejun Heo | 5122503 | 2007-06-14 04:27:25 +0900 | [diff] [blame] | 817 | kfree(dup_name); |
Tejun Heo | 5122503 | 2007-06-14 04:27:25 +0900 | [diff] [blame] | 818 | dput(old_dentry); |
| 819 | dput(new_dentry); |
Eric W. Biederman | 9918f9a | 2007-08-20 21:36:31 +0900 | [diff] [blame] | 820 | out: |
Eric W. Biederman | 932ea2e | 2007-08-20 21:36:30 +0900 | [diff] [blame] | 821 | mutex_unlock(&sysfs_rename_mutex); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 822 | return error; |
| 823 | } |
| 824 | |
Tejun Heo | 5122503 | 2007-06-14 04:27:25 +0900 | [diff] [blame] | 825 | int sysfs_move_dir(struct kobject *kobj, struct kobject *new_parent_kobj) |
Cornelia Huck | 8a82472 | 2006-11-20 17:07:51 +0100 | [diff] [blame] | 826 | { |
Tejun Heo | 5122503 | 2007-06-14 04:27:25 +0900 | [diff] [blame] | 827 | struct sysfs_dirent *sd = kobj->sd; |
| 828 | struct sysfs_dirent *new_parent_sd; |
| 829 | struct dentry *old_parent, *new_parent = NULL; |
| 830 | struct dentry *old_dentry = NULL, *new_dentry = NULL; |
Cornelia Huck | 8a82472 | 2006-11-20 17:07:51 +0100 | [diff] [blame] | 831 | int error; |
| 832 | |
Eric W. Biederman | 932ea2e | 2007-08-20 21:36:30 +0900 | [diff] [blame] | 833 | mutex_lock(&sysfs_rename_mutex); |
Tejun Heo | 5122503 | 2007-06-14 04:27:25 +0900 | [diff] [blame] | 834 | BUG_ON(!sd->s_parent); |
| 835 | 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] | 836 | |
Eric W. Biederman | 45aaae9 | 2007-08-20 21:36:31 +0900 | [diff] [blame] | 837 | error = 0; |
| 838 | if (sd->s_parent == new_parent_sd) |
| 839 | goto out; /* nothing to move */ |
| 840 | |
Tejun Heo | 5122503 | 2007-06-14 04:27:25 +0900 | [diff] [blame] | 841 | /* get dentries */ |
| 842 | old_dentry = sysfs_get_dentry(sd); |
| 843 | if (IS_ERR(old_dentry)) { |
| 844 | error = PTR_ERR(old_dentry); |
Eric W. Biederman | 45aaae9 | 2007-08-20 21:36:31 +0900 | [diff] [blame] | 845 | goto out; |
Tejun Heo | 5122503 | 2007-06-14 04:27:25 +0900 | [diff] [blame] | 846 | } |
Eric W. Biederman | 5a26b79 | 2007-08-20 21:36:30 +0900 | [diff] [blame] | 847 | old_parent = old_dentry->d_parent; |
Tejun Heo | 5122503 | 2007-06-14 04:27:25 +0900 | [diff] [blame] | 848 | |
| 849 | new_parent = sysfs_get_dentry(new_parent_sd); |
| 850 | if (IS_ERR(new_parent)) { |
| 851 | error = PTR_ERR(new_parent); |
Eric W. Biederman | 45aaae9 | 2007-08-20 21:36:31 +0900 | [diff] [blame] | 852 | goto out; |
Tejun Heo | 5122503 | 2007-06-14 04:27:25 +0900 | [diff] [blame] | 853 | } |
| 854 | |
Cornelia Huck | 8a82472 | 2006-11-20 17:07:51 +0100 | [diff] [blame] | 855 | again: |
Tejun Heo | 5122503 | 2007-06-14 04:27:25 +0900 | [diff] [blame] | 856 | mutex_lock(&old_parent->d_inode->i_mutex); |
| 857 | if (!mutex_trylock(&new_parent->d_inode->i_mutex)) { |
| 858 | mutex_unlock(&old_parent->d_inode->i_mutex); |
Cornelia Huck | 8a82472 | 2006-11-20 17:07:51 +0100 | [diff] [blame] | 859 | goto again; |
| 860 | } |
Eric W. Biederman | 45aaae9 | 2007-08-20 21:36:31 +0900 | [diff] [blame] | 861 | mutex_lock(&sysfs_mutex); |
Cornelia Huck | 8a82472 | 2006-11-20 17:07:51 +0100 | [diff] [blame] | 862 | |
Eric W. Biederman | 45aaae9 | 2007-08-20 21:36:31 +0900 | [diff] [blame] | 863 | error = -EEXIST; |
| 864 | if (sysfs_find_dirent(new_parent_sd, sd->s_name)) |
Tejun Heo | 5122503 | 2007-06-14 04:27:25 +0900 | [diff] [blame] | 865 | goto out_unlock; |
Eric W. Biederman | 45aaae9 | 2007-08-20 21:36:31 +0900 | [diff] [blame] | 866 | |
| 867 | error = -ENOMEM; |
| 868 | new_dentry = d_alloc_name(new_parent, sd->s_name); |
| 869 | if (!new_dentry) |
| 870 | goto out_unlock; |
| 871 | |
| 872 | error = 0; |
Cornelia Huck | 8a82472 | 2006-11-20 17:07:51 +0100 | [diff] [blame] | 873 | d_add(new_dentry, NULL); |
Eric W. Biederman | 5a26b79 | 2007-08-20 21:36:30 +0900 | [diff] [blame] | 874 | d_move(old_dentry, new_dentry); |
Cornelia Huck | 8a82472 | 2006-11-20 17:07:51 +0100 | [diff] [blame] | 875 | dput(new_dentry); |
| 876 | |
| 877 | /* Remove from old parent's list and insert into new parent's list. */ |
Tejun Heo | 0c73f18 | 2007-06-14 03:45:18 +0900 | [diff] [blame] | 878 | sysfs_unlink_sibling(sd); |
Tejun Heo | 7f7cfff | 2007-06-14 03:45:17 +0900 | [diff] [blame] | 879 | sysfs_get(new_parent_sd); |
| 880 | sysfs_put(sd->s_parent); |
| 881 | sd->s_parent = new_parent_sd; |
Tejun Heo | 0c73f18 | 2007-06-14 03:45:18 +0900 | [diff] [blame] | 882 | sysfs_link_sibling(sd); |
Cornelia Huck | 8a82472 | 2006-11-20 17:07:51 +0100 | [diff] [blame] | 883 | |
Tejun Heo | 5122503 | 2007-06-14 04:27:25 +0900 | [diff] [blame] | 884 | out_unlock: |
Eric W. Biederman | 45aaae9 | 2007-08-20 21:36:31 +0900 | [diff] [blame] | 885 | mutex_unlock(&sysfs_mutex); |
Tejun Heo | 5122503 | 2007-06-14 04:27:25 +0900 | [diff] [blame] | 886 | mutex_unlock(&new_parent->d_inode->i_mutex); |
| 887 | mutex_unlock(&old_parent->d_inode->i_mutex); |
Eric W. Biederman | 45aaae9 | 2007-08-20 21:36:31 +0900 | [diff] [blame] | 888 | out: |
Tejun Heo | 5122503 | 2007-06-14 04:27:25 +0900 | [diff] [blame] | 889 | dput(new_parent); |
| 890 | dput(old_dentry); |
| 891 | dput(new_dentry); |
Eric W. Biederman | 932ea2e | 2007-08-20 21:36:30 +0900 | [diff] [blame] | 892 | mutex_unlock(&sysfs_rename_mutex); |
Cornelia Huck | 8a82472 | 2006-11-20 17:07:51 +0100 | [diff] [blame] | 893 | return error; |
| 894 | } |
| 895 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 896 | /* Relationship between s_mode and the DT_xxx types */ |
| 897 | static inline unsigned char dt_type(struct sysfs_dirent *sd) |
| 898 | { |
| 899 | return (sd->s_mode >> 12) & 15; |
| 900 | } |
| 901 | |
| 902 | static int sysfs_readdir(struct file * filp, void * dirent, filldir_t filldir) |
| 903 | { |
Josef "Jeff" Sipek | f427f5d | 2006-12-08 02:36:36 -0800 | [diff] [blame] | 904 | struct dentry *dentry = filp->f_path.dentry; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 905 | struct sysfs_dirent * parent_sd = dentry->d_fsdata; |
Eric W. Biederman | 3efa65b | 2007-08-20 21:36:30 +0900 | [diff] [blame] | 906 | struct sysfs_dirent *pos; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 907 | ino_t ino; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 908 | |
Eric W. Biederman | 3efa65b | 2007-08-20 21:36:30 +0900 | [diff] [blame] | 909 | if (filp->f_pos == 0) { |
| 910 | ino = parent_sd->s_ino; |
| 911 | if (filldir(dirent, ".", 1, filp->f_pos, ino, DT_DIR) == 0) |
| 912 | filp->f_pos++; |
| 913 | } |
| 914 | if (filp->f_pos == 1) { |
| 915 | if (parent_sd->s_parent) |
| 916 | ino = parent_sd->s_parent->s_ino; |
| 917 | else |
Eric Sandeen | dc35125 | 2007-06-11 14:02:45 +0900 | [diff] [blame] | 918 | ino = parent_sd->s_ino; |
Eric W. Biederman | 3efa65b | 2007-08-20 21:36:30 +0900 | [diff] [blame] | 919 | if (filldir(dirent, "..", 2, filp->f_pos, ino, DT_DIR) == 0) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 920 | filp->f_pos++; |
Eric W. Biederman | 3efa65b | 2007-08-20 21:36:30 +0900 | [diff] [blame] | 921 | } |
| 922 | if ((filp->f_pos > 1) && (filp->f_pos < INT_MAX)) { |
| 923 | mutex_lock(&sysfs_mutex); |
| 924 | |
| 925 | /* Skip the dentries we have already reported */ |
Tejun Heo | bc747f3 | 2007-09-20 16:05:12 +0900 | [diff] [blame^] | 926 | pos = parent_sd->s_dir.children; |
Eric W. Biederman | 3efa65b | 2007-08-20 21:36:30 +0900 | [diff] [blame] | 927 | while (pos && (filp->f_pos > pos->s_ino)) |
| 928 | pos = pos->s_sibling; |
| 929 | |
| 930 | for ( ; pos; pos = pos->s_sibling) { |
| 931 | const char * name; |
| 932 | int len; |
| 933 | |
| 934 | name = pos->s_name; |
| 935 | len = strlen(name); |
| 936 | filp->f_pos = ino = pos->s_ino; |
| 937 | |
| 938 | if (filldir(dirent, name, len, filp->f_pos, ino, |
| 939 | dt_type(pos)) < 0) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 940 | break; |
Eric W. Biederman | 3efa65b | 2007-08-20 21:36:30 +0900 | [diff] [blame] | 941 | } |
| 942 | if (!pos) |
| 943 | filp->f_pos = INT_MAX; |
| 944 | mutex_unlock(&sysfs_mutex); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 945 | } |
| 946 | return 0; |
| 947 | } |
| 948 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 949 | |
Arjan van de Ven | 4b6f5d2 | 2006-03-28 01:56:42 -0800 | [diff] [blame] | 950 | const struct file_operations sysfs_dir_operations = { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 951 | .read = generic_read_dir, |
| 952 | .readdir = sysfs_readdir, |
| 953 | }; |