Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1 | /* |
Tejun Heo | 6d66f5c | 2007-09-20 17:31:38 +0900 | [diff] [blame] | 2 | * fs/sysfs/dir.c - sysfs core and dir operation implementation |
| 3 | * |
| 4 | * Copyright (c) 2001-3 Patrick Mochel |
| 5 | * Copyright (c) 2007 SUSE Linux Products GmbH |
| 6 | * Copyright (c) 2007 Tejun Heo <teheo@suse.de> |
| 7 | * |
| 8 | * This file is released under the GPLv2. |
| 9 | * |
| 10 | * Please see Documentation/filesystems/sysfs.txt for more information. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 11 | */ |
| 12 | |
| 13 | #undef DEBUG |
| 14 | |
| 15 | #include <linux/fs.h> |
| 16 | #include <linux/mount.h> |
| 17 | #include <linux/module.h> |
| 18 | #include <linux/kobject.h> |
Christoph Hellwig | 5f45f1a | 2005-06-23 00:09:12 -0700 | [diff] [blame] | 19 | #include <linux/namei.h> |
Tejun Heo | 2b611bb | 2007-06-14 03:45:13 +0900 | [diff] [blame] | 20 | #include <linux/idr.h> |
Tejun Heo | 8619f97 | 2007-06-14 03:45:18 +0900 | [diff] [blame] | 21 | #include <linux/completion.h> |
Dave Young | 869512a | 2007-07-26 14:53:53 +0000 | [diff] [blame] | 22 | #include <linux/mutex.h> |
Robert P. J. Day | c6f8773 | 2008-03-13 22:41:52 -0400 | [diff] [blame] | 23 | #include <linux/slab.h> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 24 | #include "sysfs.h" |
| 25 | |
Tejun Heo | 3007e99 | 2007-06-14 04:27:23 +0900 | [diff] [blame] | 26 | DEFINE_MUTEX(sysfs_mutex); |
Eric W. Biederman | 932ea2e | 2007-08-20 21:36:30 +0900 | [diff] [blame] | 27 | DEFINE_MUTEX(sysfs_rename_mutex); |
Roel Kluin | f7a75f0 | 2007-10-16 23:30:25 -0700 | [diff] [blame] | 28 | DEFINE_SPINLOCK(sysfs_assoc_lock); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 29 | |
Roel Kluin | f7a75f0 | 2007-10-16 23:30:25 -0700 | [diff] [blame] | 30 | static DEFINE_SPINLOCK(sysfs_ino_lock); |
Tejun Heo | 2b611bb | 2007-06-14 03:45:13 +0900 | [diff] [blame] | 31 | static DEFINE_IDA(sysfs_ino_ida); |
| 32 | |
Tejun Heo | b6b4a43 | 2007-06-14 03:45:18 +0900 | [diff] [blame] | 33 | /** |
Tejun Heo | 0c73f18 | 2007-06-14 03:45:18 +0900 | [diff] [blame] | 34 | * sysfs_link_sibling - link sysfs_dirent into sibling list |
| 35 | * @sd: sysfs_dirent of interest |
| 36 | * |
| 37 | * Link @sd into its sibling list which starts from |
Tejun Heo | bc747f3 | 2007-09-20 16:05:12 +0900 | [diff] [blame] | 38 | * sd->s_parent->s_dir.children. |
Tejun Heo | 0c73f18 | 2007-06-14 03:45:18 +0900 | [diff] [blame] | 39 | * |
| 40 | * Locking: |
Tejun Heo | 3007e99 | 2007-06-14 04:27:23 +0900 | [diff] [blame] | 41 | * mutex_lock(sysfs_mutex) |
Tejun Heo | 0c73f18 | 2007-06-14 03:45:18 +0900 | [diff] [blame] | 42 | */ |
Tejun Heo | 41fc1c2 | 2007-08-02 21:38:03 +0900 | [diff] [blame] | 43 | static void sysfs_link_sibling(struct sysfs_dirent *sd) |
Tejun Heo | 0c73f18 | 2007-06-14 03:45:18 +0900 | [diff] [blame] | 44 | { |
| 45 | struct sysfs_dirent *parent_sd = sd->s_parent; |
Eric W. Biederman | 3efa65b | 2007-08-20 21:36:30 +0900 | [diff] [blame] | 46 | struct sysfs_dirent **pos; |
Tejun Heo | 0c73f18 | 2007-06-14 03:45:18 +0900 | [diff] [blame] | 47 | |
| 48 | BUG_ON(sd->s_sibling); |
Eric W. Biederman | 3efa65b | 2007-08-20 21:36:30 +0900 | [diff] [blame] | 49 | |
| 50 | /* Store directory entries in order by ino. This allows |
| 51 | * readdir to properly restart without having to add a |
Tejun Heo | bc747f3 | 2007-09-20 16:05:12 +0900 | [diff] [blame] | 52 | * cursor into the s_dir.children list. |
Eric W. Biederman | 3efa65b | 2007-08-20 21:36:30 +0900 | [diff] [blame] | 53 | */ |
Tejun Heo | bc747f3 | 2007-09-20 16:05:12 +0900 | [diff] [blame] | 54 | 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] | 55 | if (sd->s_ino < (*pos)->s_ino) |
| 56 | break; |
| 57 | } |
| 58 | sd->s_sibling = *pos; |
| 59 | *pos = sd; |
Tejun Heo | 0c73f18 | 2007-06-14 03:45:18 +0900 | [diff] [blame] | 60 | } |
| 61 | |
| 62 | /** |
| 63 | * sysfs_unlink_sibling - unlink sysfs_dirent from sibling list |
| 64 | * @sd: sysfs_dirent of interest |
| 65 | * |
| 66 | * Unlink @sd from its sibling list which starts from |
Tejun Heo | bc747f3 | 2007-09-20 16:05:12 +0900 | [diff] [blame] | 67 | * sd->s_parent->s_dir.children. |
Tejun Heo | 0c73f18 | 2007-06-14 03:45:18 +0900 | [diff] [blame] | 68 | * |
| 69 | * Locking: |
Tejun Heo | 3007e99 | 2007-06-14 04:27:23 +0900 | [diff] [blame] | 70 | * mutex_lock(sysfs_mutex) |
Tejun Heo | 0c73f18 | 2007-06-14 03:45:18 +0900 | [diff] [blame] | 71 | */ |
Tejun Heo | 41fc1c2 | 2007-08-02 21:38:03 +0900 | [diff] [blame] | 72 | static void sysfs_unlink_sibling(struct sysfs_dirent *sd) |
Tejun Heo | 0c73f18 | 2007-06-14 03:45:18 +0900 | [diff] [blame] | 73 | { |
| 74 | struct sysfs_dirent **pos; |
| 75 | |
Tejun Heo | bc747f3 | 2007-09-20 16:05:12 +0900 | [diff] [blame] | 76 | for (pos = &sd->s_parent->s_dir.children; *pos; |
| 77 | pos = &(*pos)->s_sibling) { |
Tejun Heo | 0c73f18 | 2007-06-14 03:45:18 +0900 | [diff] [blame] | 78 | if (*pos == sd) { |
| 79 | *pos = sd->s_sibling; |
| 80 | sd->s_sibling = NULL; |
| 81 | break; |
| 82 | } |
| 83 | } |
| 84 | } |
| 85 | |
| 86 | /** |
Tejun Heo | 53e0ae9 | 2007-06-14 04:27:25 +0900 | [diff] [blame] | 87 | * sysfs_get_dentry - get dentry for the given sysfs_dirent |
| 88 | * @sd: sysfs_dirent of interest |
| 89 | * |
| 90 | * Get dentry for @sd. Dentry is looked up if currently not |
Tejun Heo | e0712bb | 2007-08-20 21:36:30 +0900 | [diff] [blame] | 91 | * present. This function descends from the root looking up |
| 92 | * dentry for each step. |
Tejun Heo | 53e0ae9 | 2007-06-14 04:27:25 +0900 | [diff] [blame] | 93 | * |
| 94 | * LOCKING: |
Eric W. Biederman | 932ea2e | 2007-08-20 21:36:30 +0900 | [diff] [blame] | 95 | * mutex_lock(sysfs_rename_mutex) |
Tejun Heo | 53e0ae9 | 2007-06-14 04:27:25 +0900 | [diff] [blame] | 96 | * |
| 97 | * RETURNS: |
| 98 | * Pointer to found dentry on success, ERR_PTR() value on error. |
| 99 | */ |
| 100 | struct dentry *sysfs_get_dentry(struct sysfs_dirent *sd) |
| 101 | { |
Tejun Heo | e0712bb | 2007-08-20 21:36:30 +0900 | [diff] [blame] | 102 | struct dentry *dentry = dget(sysfs_sb->s_root); |
Tejun Heo | 53e0ae9 | 2007-06-14 04:27:25 +0900 | [diff] [blame] | 103 | |
Tejun Heo | e0712bb | 2007-08-20 21:36:30 +0900 | [diff] [blame] | 104 | while (dentry->d_fsdata != sd) { |
| 105 | struct sysfs_dirent *cur; |
| 106 | struct dentry *parent; |
Tejun Heo | 53e0ae9 | 2007-06-14 04:27:25 +0900 | [diff] [blame] | 107 | |
Tejun Heo | e0712bb | 2007-08-20 21:36:30 +0900 | [diff] [blame] | 108 | /* find the first ancestor which hasn't been looked up */ |
| 109 | cur = sd; |
| 110 | while (cur->s_parent != dentry->d_fsdata) |
Tejun Heo | 53e0ae9 | 2007-06-14 04:27:25 +0900 | [diff] [blame] | 111 | cur = cur->s_parent; |
| 112 | |
Tejun Heo | 53e0ae9 | 2007-06-14 04:27:25 +0900 | [diff] [blame] | 113 | /* look it up */ |
Tejun Heo | e0712bb | 2007-08-20 21:36:30 +0900 | [diff] [blame] | 114 | parent = dentry; |
| 115 | mutex_lock(&parent->d_inode->i_mutex); |
Christoph Hellwig | eead191 | 2007-10-16 23:25:38 -0700 | [diff] [blame] | 116 | dentry = lookup_one_noperm(cur->s_name, parent); |
Tejun Heo | e0712bb | 2007-08-20 21:36:30 +0900 | [diff] [blame] | 117 | mutex_unlock(&parent->d_inode->i_mutex); |
| 118 | dput(parent); |
Tejun Heo | 53e0ae9 | 2007-06-14 04:27:25 +0900 | [diff] [blame] | 119 | |
Tejun Heo | e0712bb | 2007-08-20 21:36:30 +0900 | [diff] [blame] | 120 | if (IS_ERR(dentry)) |
| 121 | break; |
Tejun Heo | 53e0ae9 | 2007-06-14 04:27:25 +0900 | [diff] [blame] | 122 | } |
Tejun Heo | 53e0ae9 | 2007-06-14 04:27:25 +0900 | [diff] [blame] | 123 | return dentry; |
| 124 | } |
| 125 | |
| 126 | /** |
Tejun Heo | b6b4a43 | 2007-06-14 03:45:18 +0900 | [diff] [blame] | 127 | * sysfs_get_active - get an active reference to sysfs_dirent |
| 128 | * @sd: sysfs_dirent to get an active reference to |
| 129 | * |
| 130 | * Get an active reference of @sd. This function is noop if @sd |
| 131 | * is NULL. |
| 132 | * |
| 133 | * RETURNS: |
| 134 | * Pointer to @sd on success, NULL on failure. |
| 135 | */ |
Adrian Bunk | 78e9d36 | 2007-10-24 18:23:32 +0200 | [diff] [blame] | 136 | static struct sysfs_dirent *sysfs_get_active(struct sysfs_dirent *sd) |
Tejun Heo | b6b4a43 | 2007-06-14 03:45:18 +0900 | [diff] [blame] | 137 | { |
Tejun Heo | 8619f97 | 2007-06-14 03:45:18 +0900 | [diff] [blame] | 138 | if (unlikely(!sd)) |
| 139 | return NULL; |
| 140 | |
| 141 | while (1) { |
| 142 | int v, t; |
| 143 | |
| 144 | v = atomic_read(&sd->s_active); |
| 145 | if (unlikely(v < 0)) |
| 146 | return NULL; |
| 147 | |
| 148 | t = atomic_cmpxchg(&sd->s_active, v, v + 1); |
| 149 | if (likely(t == v)) |
| 150 | return sd; |
| 151 | if (t < 0) |
| 152 | return NULL; |
| 153 | |
| 154 | cpu_relax(); |
Tejun Heo | b6b4a43 | 2007-06-14 03:45:18 +0900 | [diff] [blame] | 155 | } |
Tejun Heo | b6b4a43 | 2007-06-14 03:45:18 +0900 | [diff] [blame] | 156 | } |
| 157 | |
| 158 | /** |
| 159 | * sysfs_put_active - put an active reference to sysfs_dirent |
| 160 | * @sd: sysfs_dirent to put an active reference to |
| 161 | * |
| 162 | * Put an active reference to @sd. This function is noop if @sd |
| 163 | * is NULL. |
| 164 | */ |
Adrian Bunk | 78e9d36 | 2007-10-24 18:23:32 +0200 | [diff] [blame] | 165 | static void sysfs_put_active(struct sysfs_dirent *sd) |
Tejun Heo | b6b4a43 | 2007-06-14 03:45:18 +0900 | [diff] [blame] | 166 | { |
Tejun Heo | 8619f97 | 2007-06-14 03:45:18 +0900 | [diff] [blame] | 167 | struct completion *cmpl; |
| 168 | int v; |
| 169 | |
| 170 | if (unlikely(!sd)) |
| 171 | return; |
| 172 | |
| 173 | v = atomic_dec_return(&sd->s_active); |
| 174 | if (likely(v != SD_DEACTIVATED_BIAS)) |
| 175 | return; |
| 176 | |
| 177 | /* atomic_dec_return() is a mb(), we'll always see the updated |
Tejun Heo | 0c73f18 | 2007-06-14 03:45:18 +0900 | [diff] [blame] | 178 | * sd->s_sibling. |
Tejun Heo | 8619f97 | 2007-06-14 03:45:18 +0900 | [diff] [blame] | 179 | */ |
Tejun Heo | 0c73f18 | 2007-06-14 03:45:18 +0900 | [diff] [blame] | 180 | cmpl = (void *)sd->s_sibling; |
Tejun Heo | 8619f97 | 2007-06-14 03:45:18 +0900 | [diff] [blame] | 181 | complete(cmpl); |
Tejun Heo | b6b4a43 | 2007-06-14 03:45:18 +0900 | [diff] [blame] | 182 | } |
| 183 | |
| 184 | /** |
| 185 | * sysfs_get_active_two - get active references to sysfs_dirent and parent |
| 186 | * @sd: sysfs_dirent of interest |
| 187 | * |
| 188 | * Get active reference to @sd and its parent. Parent's active |
| 189 | * reference is grabbed first. This function is noop if @sd is |
| 190 | * NULL. |
| 191 | * |
| 192 | * RETURNS: |
| 193 | * Pointer to @sd on success, NULL on failure. |
| 194 | */ |
| 195 | struct sysfs_dirent *sysfs_get_active_two(struct sysfs_dirent *sd) |
| 196 | { |
| 197 | if (sd) { |
| 198 | if (sd->s_parent && unlikely(!sysfs_get_active(sd->s_parent))) |
| 199 | return NULL; |
| 200 | if (unlikely(!sysfs_get_active(sd))) { |
| 201 | sysfs_put_active(sd->s_parent); |
| 202 | return NULL; |
| 203 | } |
| 204 | } |
| 205 | return sd; |
| 206 | } |
| 207 | |
| 208 | /** |
| 209 | * sysfs_put_active_two - put active references to sysfs_dirent and parent |
| 210 | * @sd: sysfs_dirent of interest |
| 211 | * |
| 212 | * Put active references to @sd and its parent. This function is |
| 213 | * noop if @sd is NULL. |
| 214 | */ |
| 215 | void sysfs_put_active_two(struct sysfs_dirent *sd) |
| 216 | { |
| 217 | if (sd) { |
| 218 | sysfs_put_active(sd); |
| 219 | sysfs_put_active(sd->s_parent); |
| 220 | } |
| 221 | } |
| 222 | |
| 223 | /** |
| 224 | * sysfs_deactivate - deactivate sysfs_dirent |
| 225 | * @sd: sysfs_dirent to deactivate |
| 226 | * |
Tejun Heo | 8619f97 | 2007-06-14 03:45:18 +0900 | [diff] [blame] | 227 | * Deny new active references and drain existing ones. |
Tejun Heo | b6b4a43 | 2007-06-14 03:45:18 +0900 | [diff] [blame] | 228 | */ |
Tejun Heo | fb6896d | 2007-06-14 04:27:24 +0900 | [diff] [blame] | 229 | static void sysfs_deactivate(struct sysfs_dirent *sd) |
Tejun Heo | b6b4a43 | 2007-06-14 03:45:18 +0900 | [diff] [blame] | 230 | { |
Tejun Heo | 8619f97 | 2007-06-14 03:45:18 +0900 | [diff] [blame] | 231 | DECLARE_COMPLETION_ONSTACK(wait); |
| 232 | int v; |
Tejun Heo | b6b4a43 | 2007-06-14 03:45:18 +0900 | [diff] [blame] | 233 | |
Tejun Heo | 380e6fb | 2007-06-14 04:27:22 +0900 | [diff] [blame] | 234 | BUG_ON(sd->s_sibling || !(sd->s_flags & SYSFS_FLAG_REMOVED)); |
Tejun Heo | 0c73f18 | 2007-06-14 03:45:18 +0900 | [diff] [blame] | 235 | sd->s_sibling = (void *)&wait; |
Tejun Heo | 8619f97 | 2007-06-14 03:45:18 +0900 | [diff] [blame] | 236 | |
| 237 | /* atomic_add_return() is a mb(), put_active() will always see |
Tejun Heo | 0c73f18 | 2007-06-14 03:45:18 +0900 | [diff] [blame] | 238 | * the updated sd->s_sibling. |
Tejun Heo | b6b4a43 | 2007-06-14 03:45:18 +0900 | [diff] [blame] | 239 | */ |
Tejun Heo | 8619f97 | 2007-06-14 03:45:18 +0900 | [diff] [blame] | 240 | v = atomic_add_return(SD_DEACTIVATED_BIAS, &sd->s_active); |
| 241 | |
| 242 | if (v != SD_DEACTIVATED_BIAS) |
| 243 | wait_for_completion(&wait); |
| 244 | |
Tejun Heo | 0c73f18 | 2007-06-14 03:45:18 +0900 | [diff] [blame] | 245 | sd->s_sibling = NULL; |
Tejun Heo | b6b4a43 | 2007-06-14 03:45:18 +0900 | [diff] [blame] | 246 | } |
| 247 | |
Tejun Heo | 42b37df | 2007-06-14 03:45:17 +0900 | [diff] [blame] | 248 | static int sysfs_alloc_ino(ino_t *pino) |
Tejun Heo | 2b611bb | 2007-06-14 03:45:13 +0900 | [diff] [blame] | 249 | { |
| 250 | int ino, rc; |
| 251 | |
| 252 | retry: |
| 253 | spin_lock(&sysfs_ino_lock); |
| 254 | rc = ida_get_new_above(&sysfs_ino_ida, 2, &ino); |
| 255 | spin_unlock(&sysfs_ino_lock); |
| 256 | |
| 257 | if (rc == -EAGAIN) { |
| 258 | if (ida_pre_get(&sysfs_ino_ida, GFP_KERNEL)) |
| 259 | goto retry; |
| 260 | rc = -ENOMEM; |
| 261 | } |
| 262 | |
| 263 | *pino = ino; |
| 264 | return rc; |
| 265 | } |
| 266 | |
| 267 | static void sysfs_free_ino(ino_t ino) |
| 268 | { |
| 269 | spin_lock(&sysfs_ino_lock); |
| 270 | ida_remove(&sysfs_ino_ida, ino); |
| 271 | spin_unlock(&sysfs_ino_lock); |
| 272 | } |
| 273 | |
Tejun Heo | fa7f912 | 2007-06-14 03:45:13 +0900 | [diff] [blame] | 274 | void release_sysfs_dirent(struct sysfs_dirent * sd) |
| 275 | { |
Tejun Heo | 13b3086 | 2007-06-14 03:45:14 +0900 | [diff] [blame] | 276 | struct sysfs_dirent *parent_sd; |
| 277 | |
| 278 | repeat: |
Tejun Heo | 3007e99 | 2007-06-14 04:27:23 +0900 | [diff] [blame] | 279 | /* Moving/renaming is always done while holding reference. |
| 280 | * sd->s_parent won't change beneath us. |
| 281 | */ |
Tejun Heo | 13b3086 | 2007-06-14 03:45:14 +0900 | [diff] [blame] | 282 | parent_sd = sd->s_parent; |
| 283 | |
Tejun Heo | b402d72 | 2007-06-14 04:27:21 +0900 | [diff] [blame] | 284 | if (sysfs_type(sd) == SYSFS_KOBJ_LINK) |
Tejun Heo | b1fc3d6 | 2007-09-20 16:05:11 +0900 | [diff] [blame] | 285 | sysfs_put(sd->s_symlink.target_sd); |
Tejun Heo | b402d72 | 2007-06-14 04:27:21 +0900 | [diff] [blame] | 286 | if (sysfs_type(sd) & SYSFS_COPY_NAME) |
Tejun Heo | 0c096b5 | 2007-06-14 03:45:15 +0900 | [diff] [blame] | 287 | kfree(sd->s_name); |
Tejun Heo | fa7f912 | 2007-06-14 03:45:13 +0900 | [diff] [blame] | 288 | kfree(sd->s_iattr); |
Tejun Heo | 2b611bb | 2007-06-14 03:45:13 +0900 | [diff] [blame] | 289 | sysfs_free_ino(sd->s_ino); |
Tejun Heo | fa7f912 | 2007-06-14 03:45:13 +0900 | [diff] [blame] | 290 | kmem_cache_free(sysfs_dir_cachep, sd); |
Tejun Heo | 13b3086 | 2007-06-14 03:45:14 +0900 | [diff] [blame] | 291 | |
| 292 | sd = parent_sd; |
| 293 | if (sd && atomic_dec_and_test(&sd->s_count)) |
| 294 | goto repeat; |
Tejun Heo | fa7f912 | 2007-06-14 03:45:13 +0900 | [diff] [blame] | 295 | } |
| 296 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 297 | static void sysfs_d_iput(struct dentry * dentry, struct inode * inode) |
| 298 | { |
| 299 | struct sysfs_dirent * sd = dentry->d_fsdata; |
| 300 | |
Eric W. Biederman | 5a26b79 | 2007-08-20 21:36:30 +0900 | [diff] [blame] | 301 | sysfs_put(sd); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 302 | iput(inode); |
| 303 | } |
| 304 | |
Al Viro | ee1ec32 | 2009-02-20 06:01:46 +0000 | [diff] [blame] | 305 | static const struct dentry_operations sysfs_dentry_ops = { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 306 | .d_iput = sysfs_d_iput, |
| 307 | }; |
| 308 | |
Tejun Heo | 3e51903 | 2007-06-14 03:45:15 +0900 | [diff] [blame] | 309 | 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] | 310 | { |
Tejun Heo | 0c096b5 | 2007-06-14 03:45:15 +0900 | [diff] [blame] | 311 | char *dup_name = NULL; |
Akinobu Mita | 01da242 | 2007-07-14 11:03:35 +0900 | [diff] [blame] | 312 | struct sysfs_dirent *sd; |
Tejun Heo | 0c096b5 | 2007-06-14 03:45:15 +0900 | [diff] [blame] | 313 | |
| 314 | if (type & SYSFS_COPY_NAME) { |
| 315 | name = dup_name = kstrdup(name, GFP_KERNEL); |
| 316 | if (!name) |
Akinobu Mita | 01da242 | 2007-07-14 11:03:35 +0900 | [diff] [blame] | 317 | return NULL; |
Tejun Heo | 0c096b5 | 2007-06-14 03:45:15 +0900 | [diff] [blame] | 318 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 319 | |
Robert P. J. Day | c376222 | 2007-02-10 01:45:03 -0800 | [diff] [blame] | 320 | sd = kmem_cache_zalloc(sysfs_dir_cachep, GFP_KERNEL); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 321 | if (!sd) |
Akinobu Mita | 01da242 | 2007-07-14 11:03:35 +0900 | [diff] [blame] | 322 | goto err_out1; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 323 | |
Tejun Heo | 0c096b5 | 2007-06-14 03:45:15 +0900 | [diff] [blame] | 324 | if (sysfs_alloc_ino(&sd->s_ino)) |
Akinobu Mita | 01da242 | 2007-07-14 11:03:35 +0900 | [diff] [blame] | 325 | goto err_out2; |
Tejun Heo | 2b611bb | 2007-06-14 03:45:13 +0900 | [diff] [blame] | 326 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 327 | atomic_set(&sd->s_count, 1); |
Tejun Heo | 8619f97 | 2007-06-14 03:45:18 +0900 | [diff] [blame] | 328 | atomic_set(&sd->s_active, 0); |
Tejun Heo | a26cd72 | 2007-06-14 03:45:14 +0900 | [diff] [blame] | 329 | |
Tejun Heo | 0c096b5 | 2007-06-14 03:45:15 +0900 | [diff] [blame] | 330 | sd->s_name = name; |
Tejun Heo | a26cd72 | 2007-06-14 03:45:14 +0900 | [diff] [blame] | 331 | sd->s_mode = mode; |
Tejun Heo | b402d72 | 2007-06-14 04:27:21 +0900 | [diff] [blame] | 332 | sd->s_flags = type; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 333 | |
| 334 | return sd; |
Tejun Heo | 0c096b5 | 2007-06-14 03:45:15 +0900 | [diff] [blame] | 335 | |
Akinobu Mita | 01da242 | 2007-07-14 11:03:35 +0900 | [diff] [blame] | 336 | err_out2: |
Tejun Heo | 0c096b5 | 2007-06-14 03:45:15 +0900 | [diff] [blame] | 337 | kmem_cache_free(sysfs_dir_cachep, sd); |
Akinobu Mita | 01da242 | 2007-07-14 11:03:35 +0900 | [diff] [blame] | 338 | err_out1: |
| 339 | kfree(dup_name); |
Tejun Heo | 0c096b5 | 2007-06-14 03:45:15 +0900 | [diff] [blame] | 340 | return NULL; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 341 | } |
| 342 | |
Tejun Heo | fb6896d | 2007-06-14 04:27:24 +0900 | [diff] [blame] | 343 | static int sysfs_ilookup_test(struct inode *inode, void *arg) |
| 344 | { |
| 345 | struct sysfs_dirent *sd = arg; |
| 346 | return inode->i_ino == sd->s_ino; |
| 347 | } |
| 348 | |
Tejun Heo | 3007e99 | 2007-06-14 04:27:23 +0900 | [diff] [blame] | 349 | /** |
Tejun Heo | fb6896d | 2007-06-14 04:27:24 +0900 | [diff] [blame] | 350 | * sysfs_addrm_start - prepare for sysfs_dirent add/remove |
| 351 | * @acxt: pointer to sysfs_addrm_cxt to be used |
| 352 | * @parent_sd: parent sysfs_dirent |
Tejun Heo | 3007e99 | 2007-06-14 04:27:23 +0900 | [diff] [blame] | 353 | * |
Tejun Heo | fb6896d | 2007-06-14 04:27:24 +0900 | [diff] [blame] | 354 | * This function is called when the caller is about to add or |
| 355 | * remove sysfs_dirent under @parent_sd. This function acquires |
| 356 | * sysfs_mutex, grabs inode for @parent_sd if available and lock |
| 357 | * i_mutex of it. @acxt is used to keep and pass context to |
| 358 | * other addrm functions. |
Tejun Heo | 3007e99 | 2007-06-14 04:27:23 +0900 | [diff] [blame] | 359 | * |
| 360 | * LOCKING: |
Tejun Heo | fb6896d | 2007-06-14 04:27:24 +0900 | [diff] [blame] | 361 | * Kernel thread context (may sleep). sysfs_mutex is locked on |
| 362 | * return. i_mutex of parent inode is locked on return if |
| 363 | * available. |
Tejun Heo | 3007e99 | 2007-06-14 04:27:23 +0900 | [diff] [blame] | 364 | */ |
Tejun Heo | fb6896d | 2007-06-14 04:27:24 +0900 | [diff] [blame] | 365 | void sysfs_addrm_start(struct sysfs_addrm_cxt *acxt, |
| 366 | struct sysfs_dirent *parent_sd) |
Eric W. Biederman | b592fcf | 2007-01-24 12:35:52 -0700 | [diff] [blame] | 367 | { |
Tejun Heo | fb6896d | 2007-06-14 04:27:24 +0900 | [diff] [blame] | 368 | struct inode *inode; |
Tejun Heo | a26cd72 | 2007-06-14 03:45:14 +0900 | [diff] [blame] | 369 | |
Tejun Heo | fb6896d | 2007-06-14 04:27:24 +0900 | [diff] [blame] | 370 | memset(acxt, 0, sizeof(*acxt)); |
| 371 | acxt->parent_sd = parent_sd; |
| 372 | |
Tejun Heo | 45c076c | 2008-09-28 07:48:08 +0900 | [diff] [blame] | 373 | /* Lookup parent inode. inode initialization is protected by |
| 374 | * sysfs_mutex, so inode existence can be determined by |
| 375 | * looking up inode while holding sysfs_mutex. |
Tejun Heo | fb6896d | 2007-06-14 04:27:24 +0900 | [diff] [blame] | 376 | */ |
| 377 | mutex_lock(&sysfs_mutex); |
| 378 | |
Tejun Heo | 45c076c | 2008-09-28 07:48:08 +0900 | [diff] [blame] | 379 | inode = ilookup5(sysfs_sb, parent_sd->s_ino, sysfs_ilookup_test, |
| 380 | parent_sd); |
| 381 | if (inode) { |
| 382 | WARN_ON(inode->i_state & I_NEW); |
Tejun Heo | fb6896d | 2007-06-14 04:27:24 +0900 | [diff] [blame] | 383 | |
Tejun Heo | fb6896d | 2007-06-14 04:27:24 +0900 | [diff] [blame] | 384 | /* parent inode available */ |
| 385 | acxt->parent_inode = inode; |
| 386 | |
| 387 | /* sysfs_mutex is below i_mutex in lock hierarchy. |
| 388 | * First, trylock i_mutex. If fails, unlock |
| 389 | * sysfs_mutex and lock them in order. |
| 390 | */ |
| 391 | if (!mutex_trylock(&inode->i_mutex)) { |
| 392 | mutex_unlock(&sysfs_mutex); |
| 393 | mutex_lock(&inode->i_mutex); |
| 394 | mutex_lock(&sysfs_mutex); |
| 395 | } |
Tejun Heo | 45c076c | 2008-09-28 07:48:08 +0900 | [diff] [blame] | 396 | } |
Tejun Heo | fb6896d | 2007-06-14 04:27:24 +0900 | [diff] [blame] | 397 | } |
| 398 | |
| 399 | /** |
Cornelia Huck | 36ce6da | 2008-06-10 11:09:08 +0200 | [diff] [blame] | 400 | * __sysfs_add_one - add sysfs_dirent to parent without warning |
| 401 | * @acxt: addrm context to use |
| 402 | * @sd: sysfs_dirent to be added |
| 403 | * |
| 404 | * Get @acxt->parent_sd and set sd->s_parent to it and increment |
| 405 | * nlink of parent inode if @sd is a directory and link into the |
| 406 | * children list of the parent. |
| 407 | * |
| 408 | * This function should be called between calls to |
| 409 | * sysfs_addrm_start() and sysfs_addrm_finish() and should be |
| 410 | * passed the same @acxt as passed to sysfs_addrm_start(). |
| 411 | * |
| 412 | * LOCKING: |
| 413 | * Determined by sysfs_addrm_start(). |
| 414 | * |
| 415 | * RETURNS: |
| 416 | * 0 on success, -EEXIST if entry with the given name already |
| 417 | * exists. |
| 418 | */ |
| 419 | int __sysfs_add_one(struct sysfs_addrm_cxt *acxt, struct sysfs_dirent *sd) |
| 420 | { |
| 421 | if (sysfs_find_dirent(acxt->parent_sd, sd->s_name)) |
| 422 | return -EEXIST; |
| 423 | |
| 424 | sd->s_parent = sysfs_get(acxt->parent_sd); |
| 425 | |
| 426 | if (sysfs_type(sd) == SYSFS_DIR && acxt->parent_inode) |
| 427 | inc_nlink(acxt->parent_inode); |
| 428 | |
| 429 | acxt->cnt++; |
| 430 | |
| 431 | sysfs_link_sibling(sd); |
| 432 | |
| 433 | return 0; |
| 434 | } |
| 435 | |
| 436 | /** |
Alex Chiang | 425cb02 | 2009-02-12 10:56:59 -0700 | [diff] [blame] | 437 | * sysfs_pathname - return full path to sysfs dirent |
| 438 | * @sd: sysfs_dirent whose path we want |
| 439 | * @path: caller allocated buffer |
| 440 | * |
| 441 | * Gives the name "/" to the sysfs_root entry; any path returned |
| 442 | * is relative to wherever sysfs is mounted. |
| 443 | * |
| 444 | * XXX: does no error checking on @path size |
| 445 | */ |
| 446 | static char *sysfs_pathname(struct sysfs_dirent *sd, char *path) |
| 447 | { |
| 448 | if (sd->s_parent) { |
| 449 | sysfs_pathname(sd->s_parent, path); |
| 450 | strcat(path, "/"); |
| 451 | } |
| 452 | strcat(path, sd->s_name); |
| 453 | return path; |
| 454 | } |
| 455 | |
| 456 | /** |
Tejun Heo | fb6896d | 2007-06-14 04:27:24 +0900 | [diff] [blame] | 457 | * sysfs_add_one - add sysfs_dirent to parent |
| 458 | * @acxt: addrm context to use |
| 459 | * @sd: sysfs_dirent to be added |
| 460 | * |
| 461 | * 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] | 462 | * nlink of parent inode if @sd is a directory and link into the |
| 463 | * children list of the parent. |
Tejun Heo | fb6896d | 2007-06-14 04:27:24 +0900 | [diff] [blame] | 464 | * |
| 465 | * This function should be called between calls to |
| 466 | * sysfs_addrm_start() and sysfs_addrm_finish() and should be |
| 467 | * passed the same @acxt as passed to sysfs_addrm_start(). |
| 468 | * |
| 469 | * LOCKING: |
| 470 | * Determined by sysfs_addrm_start(). |
Tejun Heo | 23dc279 | 2007-08-02 21:38:03 +0900 | [diff] [blame] | 471 | * |
| 472 | * RETURNS: |
| 473 | * 0 on success, -EEXIST if entry with the given name already |
| 474 | * exists. |
Tejun Heo | fb6896d | 2007-06-14 04:27:24 +0900 | [diff] [blame] | 475 | */ |
Tejun Heo | 23dc279 | 2007-08-02 21:38:03 +0900 | [diff] [blame] | 476 | 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] | 477 | { |
Cornelia Huck | 36ce6da | 2008-06-10 11:09:08 +0200 | [diff] [blame] | 478 | int ret; |
Tejun Heo | 23dc279 | 2007-08-02 21:38:03 +0900 | [diff] [blame] | 479 | |
Cornelia Huck | 36ce6da | 2008-06-10 11:09:08 +0200 | [diff] [blame] | 480 | ret = __sysfs_add_one(acxt, sd); |
Alex Chiang | 425cb02 | 2009-02-12 10:56:59 -0700 | [diff] [blame] | 481 | if (ret == -EEXIST) { |
| 482 | char *path = kzalloc(PATH_MAX, GFP_KERNEL); |
| 483 | WARN(1, KERN_WARNING |
| 484 | "sysfs: cannot create duplicate filename '%s'\n", |
| 485 | (path == NULL) ? sd->s_name : |
| 486 | strcat(strcat(sysfs_pathname(acxt->parent_sd, path), "/"), |
| 487 | sd->s_name)); |
| 488 | kfree(path); |
| 489 | } |
| 490 | |
Cornelia Huck | 36ce6da | 2008-06-10 11:09:08 +0200 | [diff] [blame] | 491 | return ret; |
Tejun Heo | fb6896d | 2007-06-14 04:27:24 +0900 | [diff] [blame] | 492 | } |
| 493 | |
| 494 | /** |
| 495 | * sysfs_remove_one - remove sysfs_dirent from parent |
| 496 | * @acxt: addrm context to use |
Jean Delvare | 9fd5b1c | 2008-01-08 18:11:24 +0100 | [diff] [blame] | 497 | * @sd: sysfs_dirent to be removed |
Tejun Heo | fb6896d | 2007-06-14 04:27:24 +0900 | [diff] [blame] | 498 | * |
| 499 | * 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] | 500 | * directory. @sd is unlinked from the children list. |
Tejun Heo | fb6896d | 2007-06-14 04:27:24 +0900 | [diff] [blame] | 501 | * |
| 502 | * This function should be called between calls to |
| 503 | * sysfs_addrm_start() and sysfs_addrm_finish() and should be |
| 504 | * passed the same @acxt as passed to sysfs_addrm_start(). |
| 505 | * |
| 506 | * LOCKING: |
| 507 | * Determined by sysfs_addrm_start(). |
| 508 | */ |
| 509 | void sysfs_remove_one(struct sysfs_addrm_cxt *acxt, struct sysfs_dirent *sd) |
| 510 | { |
Tejun Heo | 41fc1c2 | 2007-08-02 21:38:03 +0900 | [diff] [blame] | 511 | BUG_ON(sd->s_flags & SYSFS_FLAG_REMOVED); |
| 512 | |
| 513 | sysfs_unlink_sibling(sd); |
Tejun Heo | fb6896d | 2007-06-14 04:27:24 +0900 | [diff] [blame] | 514 | |
| 515 | sd->s_flags |= SYSFS_FLAG_REMOVED; |
| 516 | sd->s_sibling = acxt->removed; |
| 517 | acxt->removed = sd; |
| 518 | |
| 519 | if (sysfs_type(sd) == SYSFS_DIR && acxt->parent_inode) |
| 520 | drop_nlink(acxt->parent_inode); |
| 521 | |
| 522 | acxt->cnt++; |
| 523 | } |
| 524 | |
| 525 | /** |
Tejun Heo | a0edd7c | 2007-06-14 04:27:24 +0900 | [diff] [blame] | 526 | * sysfs_drop_dentry - drop dentry for the specified sysfs_dirent |
| 527 | * @sd: target sysfs_dirent |
| 528 | * |
| 529 | * Drop dentry for @sd. @sd must have been unlinked from its |
| 530 | * parent on entry to this function such that it can't be looked |
| 531 | * up anymore. |
Tejun Heo | a0edd7c | 2007-06-14 04:27:24 +0900 | [diff] [blame] | 532 | */ |
| 533 | static void sysfs_drop_dentry(struct sysfs_dirent *sd) |
| 534 | { |
Tejun Heo | a0edd7c | 2007-06-14 04:27:24 +0900 | [diff] [blame] | 535 | struct inode *inode; |
Eric W. Biederman | 89bec09 | 2007-08-20 21:36:30 +0900 | [diff] [blame] | 536 | struct dentry *dentry; |
Tejun Heo | a0edd7c | 2007-06-14 04:27:24 +0900 | [diff] [blame] | 537 | |
Eric W. Biederman | 89bec09 | 2007-08-20 21:36:30 +0900 | [diff] [blame] | 538 | inode = ilookup(sysfs_sb, sd->s_ino); |
| 539 | if (!inode) |
| 540 | return; |
| 541 | |
| 542 | /* Drop any existing dentries associated with sd. |
| 543 | * |
| 544 | * For the dentry to be properly freed we need to grab a |
| 545 | * reference to the dentry under the dcache lock, unhash it, |
| 546 | * and then put it. The playing with the dentry count allows |
| 547 | * dput to immediately free the dentry if it is not in use. |
Tejun Heo | a0edd7c | 2007-06-14 04:27:24 +0900 | [diff] [blame] | 548 | */ |
Eric W. Biederman | 89bec09 | 2007-08-20 21:36:30 +0900 | [diff] [blame] | 549 | repeat: |
Tejun Heo | a0edd7c | 2007-06-14 04:27:24 +0900 | [diff] [blame] | 550 | spin_lock(&dcache_lock); |
Eric W. Biederman | 89bec09 | 2007-08-20 21:36:30 +0900 | [diff] [blame] | 551 | list_for_each_entry(dentry, &inode->i_dentry, d_alias) { |
| 552 | if (d_unhashed(dentry)) |
| 553 | continue; |
| 554 | dget_locked(dentry); |
Tejun Heo | a0edd7c | 2007-06-14 04:27:24 +0900 | [diff] [blame] | 555 | spin_lock(&dentry->d_lock); |
| 556 | __d_drop(dentry); |
| 557 | spin_unlock(&dentry->d_lock); |
Eric W. Biederman | 89bec09 | 2007-08-20 21:36:30 +0900 | [diff] [blame] | 558 | spin_unlock(&dcache_lock); |
| 559 | dput(dentry); |
| 560 | goto repeat; |
Tejun Heo | a0edd7c | 2007-06-14 04:27:24 +0900 | [diff] [blame] | 561 | } |
Tejun Heo | a0edd7c | 2007-06-14 04:27:24 +0900 | [diff] [blame] | 562 | spin_unlock(&dcache_lock); |
Tejun Heo | a0edd7c | 2007-06-14 04:27:24 +0900 | [diff] [blame] | 563 | |
| 564 | /* adjust nlink and update timestamp */ |
Eric W. Biederman | 89bec09 | 2007-08-20 21:36:30 +0900 | [diff] [blame] | 565 | mutex_lock(&inode->i_mutex); |
Tejun Heo | a0edd7c | 2007-06-14 04:27:24 +0900 | [diff] [blame] | 566 | |
Eric W. Biederman | 89bec09 | 2007-08-20 21:36:30 +0900 | [diff] [blame] | 567 | inode->i_ctime = CURRENT_TIME; |
| 568 | drop_nlink(inode); |
| 569 | if (sysfs_type(sd) == SYSFS_DIR) |
Tejun Heo | a0edd7c | 2007-06-14 04:27:24 +0900 | [diff] [blame] | 570 | drop_nlink(inode); |
Tejun Heo | a0edd7c | 2007-06-14 04:27:24 +0900 | [diff] [blame] | 571 | |
Eric W. Biederman | 89bec09 | 2007-08-20 21:36:30 +0900 | [diff] [blame] | 572 | mutex_unlock(&inode->i_mutex); |
| 573 | |
| 574 | iput(inode); |
Tejun Heo | a0edd7c | 2007-06-14 04:27:24 +0900 | [diff] [blame] | 575 | } |
| 576 | |
| 577 | /** |
Tejun Heo | fb6896d | 2007-06-14 04:27:24 +0900 | [diff] [blame] | 578 | * sysfs_addrm_finish - finish up sysfs_dirent add/remove |
| 579 | * @acxt: addrm context to finish up |
| 580 | * |
| 581 | * Finish up sysfs_dirent add/remove. Resources acquired by |
| 582 | * sysfs_addrm_start() are released and removed sysfs_dirents are |
| 583 | * cleaned up. Timestamps on the parent inode are updated. |
| 584 | * |
| 585 | * LOCKING: |
| 586 | * All mutexes acquired by sysfs_addrm_start() are released. |
Tejun Heo | fb6896d | 2007-06-14 04:27:24 +0900 | [diff] [blame] | 587 | */ |
Tejun Heo | 990e53f | 2007-08-02 21:38:03 +0900 | [diff] [blame] | 588 | void sysfs_addrm_finish(struct sysfs_addrm_cxt *acxt) |
Tejun Heo | fb6896d | 2007-06-14 04:27:24 +0900 | [diff] [blame] | 589 | { |
| 590 | /* release resources acquired by sysfs_addrm_start() */ |
| 591 | mutex_unlock(&sysfs_mutex); |
| 592 | if (acxt->parent_inode) { |
| 593 | struct inode *inode = acxt->parent_inode; |
| 594 | |
| 595 | /* if added/removed, update timestamps on the parent */ |
| 596 | if (acxt->cnt) |
| 597 | inode->i_ctime = inode->i_mtime = CURRENT_TIME; |
| 598 | |
| 599 | mutex_unlock(&inode->i_mutex); |
| 600 | iput(inode); |
Tejun Heo | 13b3086 | 2007-06-14 03:45:14 +0900 | [diff] [blame] | 601 | } |
Tejun Heo | fb6896d | 2007-06-14 04:27:24 +0900 | [diff] [blame] | 602 | |
| 603 | /* kill removed sysfs_dirents */ |
| 604 | while (acxt->removed) { |
| 605 | struct sysfs_dirent *sd = acxt->removed; |
| 606 | |
| 607 | acxt->removed = sd->s_sibling; |
| 608 | sd->s_sibling = NULL; |
| 609 | |
| 610 | sysfs_drop_dentry(sd); |
| 611 | sysfs_deactivate(sd); |
Eric W. Biederman | e0edd3c | 2009-03-04 11:57:20 -0800 | [diff] [blame] | 612 | unmap_bin_file(sd); |
Tejun Heo | fb6896d | 2007-06-14 04:27:24 +0900 | [diff] [blame] | 613 | sysfs_put(sd); |
| 614 | } |
Eric W. Biederman | b592fcf | 2007-01-24 12:35:52 -0700 | [diff] [blame] | 615 | } |
| 616 | |
Tejun Heo | f0b0af4 | 2007-06-14 04:27:22 +0900 | [diff] [blame] | 617 | /** |
| 618 | * sysfs_find_dirent - find sysfs_dirent with the given name |
| 619 | * @parent_sd: sysfs_dirent to search under |
| 620 | * @name: name to look for |
Maneesh Soni | c516865 | 2006-03-09 19:40:14 +0530 | [diff] [blame] | 621 | * |
Tejun Heo | f0b0af4 | 2007-06-14 04:27:22 +0900 | [diff] [blame] | 622 | * Look for sysfs_dirent with name @name under @parent_sd. |
Maneesh Soni | c516865 | 2006-03-09 19:40:14 +0530 | [diff] [blame] | 623 | * |
Tejun Heo | f0b0af4 | 2007-06-14 04:27:22 +0900 | [diff] [blame] | 624 | * LOCKING: |
Tejun Heo | 3007e99 | 2007-06-14 04:27:23 +0900 | [diff] [blame] | 625 | * mutex_lock(sysfs_mutex) |
Tejun Heo | f0b0af4 | 2007-06-14 04:27:22 +0900 | [diff] [blame] | 626 | * |
| 627 | * RETURNS: |
| 628 | * Pointer to sysfs_dirent if found, NULL if not. |
Maneesh Soni | c516865 | 2006-03-09 19:40:14 +0530 | [diff] [blame] | 629 | */ |
Tejun Heo | f0b0af4 | 2007-06-14 04:27:22 +0900 | [diff] [blame] | 630 | struct sysfs_dirent *sysfs_find_dirent(struct sysfs_dirent *parent_sd, |
| 631 | const unsigned char *name) |
Maneesh Soni | c516865 | 2006-03-09 19:40:14 +0530 | [diff] [blame] | 632 | { |
Tejun Heo | f0b0af4 | 2007-06-14 04:27:22 +0900 | [diff] [blame] | 633 | struct sysfs_dirent *sd; |
Maneesh Soni | c516865 | 2006-03-09 19:40:14 +0530 | [diff] [blame] | 634 | |
Tejun Heo | bc747f3 | 2007-09-20 16:05:12 +0900 | [diff] [blame] | 635 | 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] | 636 | if (!strcmp(sd->s_name, name)) |
Tejun Heo | f0b0af4 | 2007-06-14 04:27:22 +0900 | [diff] [blame] | 637 | return sd; |
| 638 | return NULL; |
| 639 | } |
Maneesh Soni | c516865 | 2006-03-09 19:40:14 +0530 | [diff] [blame] | 640 | |
Tejun Heo | f0b0af4 | 2007-06-14 04:27:22 +0900 | [diff] [blame] | 641 | /** |
| 642 | * sysfs_get_dirent - find and get sysfs_dirent with the given name |
| 643 | * @parent_sd: sysfs_dirent to search under |
| 644 | * @name: name to look for |
| 645 | * |
| 646 | * Look for sysfs_dirent with name @name under @parent_sd and get |
| 647 | * it if found. |
| 648 | * |
| 649 | * LOCKING: |
Tejun Heo | 3007e99 | 2007-06-14 04:27:23 +0900 | [diff] [blame] | 650 | * Kernel thread context (may sleep). Grabs sysfs_mutex. |
Tejun Heo | f0b0af4 | 2007-06-14 04:27:22 +0900 | [diff] [blame] | 651 | * |
| 652 | * RETURNS: |
| 653 | * Pointer to sysfs_dirent if found, NULL if not. |
| 654 | */ |
| 655 | struct sysfs_dirent *sysfs_get_dirent(struct sysfs_dirent *parent_sd, |
| 656 | const unsigned char *name) |
| 657 | { |
| 658 | struct sysfs_dirent *sd; |
| 659 | |
Tejun Heo | 3007e99 | 2007-06-14 04:27:23 +0900 | [diff] [blame] | 660 | mutex_lock(&sysfs_mutex); |
Tejun Heo | f0b0af4 | 2007-06-14 04:27:22 +0900 | [diff] [blame] | 661 | sd = sysfs_find_dirent(parent_sd, name); |
| 662 | sysfs_get(sd); |
Tejun Heo | 3007e99 | 2007-06-14 04:27:23 +0900 | [diff] [blame] | 663 | mutex_unlock(&sysfs_mutex); |
Tejun Heo | f0b0af4 | 2007-06-14 04:27:22 +0900 | [diff] [blame] | 664 | |
| 665 | return sd; |
Maneesh Soni | c516865 | 2006-03-09 19:40:14 +0530 | [diff] [blame] | 666 | } |
Neil Brown | f1282c8 | 2008-07-16 08:58:04 +1000 | [diff] [blame] | 667 | EXPORT_SYMBOL_GPL(sysfs_get_dirent); |
Maneesh Soni | c516865 | 2006-03-09 19:40:14 +0530 | [diff] [blame] | 668 | |
Tejun Heo | 608e266 | 2007-06-14 04:27:22 +0900 | [diff] [blame] | 669 | static int create_dir(struct kobject *kobj, struct sysfs_dirent *parent_sd, |
| 670 | const char *name, struct sysfs_dirent **p_sd) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 671 | { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 672 | umode_t mode = S_IFDIR| S_IRWXU | S_IRUGO | S_IXUGO; |
Tejun Heo | 5122503 | 2007-06-14 04:27:25 +0900 | [diff] [blame] | 673 | struct sysfs_addrm_cxt acxt; |
Tejun Heo | dfeb9fb | 2007-06-14 03:45:14 +0900 | [diff] [blame] | 674 | struct sysfs_dirent *sd; |
Tejun Heo | 23dc279 | 2007-08-02 21:38:03 +0900 | [diff] [blame] | 675 | int rc; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 676 | |
Tejun Heo | fc9f54b | 2007-06-14 03:45:17 +0900 | [diff] [blame] | 677 | /* allocate */ |
Tejun Heo | 3e51903 | 2007-06-14 03:45:15 +0900 | [diff] [blame] | 678 | sd = sysfs_new_dirent(name, mode, SYSFS_DIR); |
Tejun Heo | a26cd72 | 2007-06-14 03:45:14 +0900 | [diff] [blame] | 679 | if (!sd) |
Tejun Heo | 5122503 | 2007-06-14 04:27:25 +0900 | [diff] [blame] | 680 | return -ENOMEM; |
Tejun Heo | b1fc3d6 | 2007-09-20 16:05:11 +0900 | [diff] [blame] | 681 | sd->s_dir.kobj = kobj; |
Tejun Heo | dfeb9fb | 2007-06-14 03:45:14 +0900 | [diff] [blame] | 682 | |
Tejun Heo | 5122503 | 2007-06-14 04:27:25 +0900 | [diff] [blame] | 683 | /* link in */ |
| 684 | sysfs_addrm_start(&acxt, parent_sd); |
Tejun Heo | 23dc279 | 2007-08-02 21:38:03 +0900 | [diff] [blame] | 685 | rc = sysfs_add_one(&acxt, sd); |
| 686 | sysfs_addrm_finish(&acxt); |
Tejun Heo | 967e35d | 2007-07-18 16:38:11 +0900 | [diff] [blame] | 687 | |
Tejun Heo | 23dc279 | 2007-08-02 21:38:03 +0900 | [diff] [blame] | 688 | if (rc == 0) |
| 689 | *p_sd = sd; |
| 690 | else |
Tejun Heo | 967e35d | 2007-07-18 16:38:11 +0900 | [diff] [blame] | 691 | sysfs_put(sd); |
Tejun Heo | fc9f54b | 2007-06-14 03:45:17 +0900 | [diff] [blame] | 692 | |
Tejun Heo | 23dc279 | 2007-08-02 21:38:03 +0900 | [diff] [blame] | 693 | return rc; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 694 | } |
| 695 | |
Tejun Heo | 608e266 | 2007-06-14 04:27:22 +0900 | [diff] [blame] | 696 | int sysfs_create_subdir(struct kobject *kobj, const char *name, |
| 697 | struct sysfs_dirent **p_sd) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 698 | { |
Tejun Heo | 608e266 | 2007-06-14 04:27:22 +0900 | [diff] [blame] | 699 | return create_dir(kobj, kobj->sd, name, p_sd); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 700 | } |
| 701 | |
| 702 | /** |
| 703 | * sysfs_create_dir - create a directory for an object. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 704 | * @kobj: object we're creating directory for. |
| 705 | */ |
Eric W. Biederman | 90bc613 | 2007-07-31 19:15:08 +0900 | [diff] [blame] | 706 | int sysfs_create_dir(struct kobject * kobj) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 707 | { |
Tejun Heo | 608e266 | 2007-06-14 04:27:22 +0900 | [diff] [blame] | 708 | struct sysfs_dirent *parent_sd, *sd; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 709 | int error = 0; |
| 710 | |
| 711 | BUG_ON(!kobj); |
| 712 | |
Eric W. Biederman | 90bc613 | 2007-07-31 19:15:08 +0900 | [diff] [blame] | 713 | if (kobj->parent) |
Tejun Heo | 608e266 | 2007-06-14 04:27:22 +0900 | [diff] [blame] | 714 | parent_sd = kobj->parent->sd; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 715 | else |
Eric W. Biederman | 7d0c7d6 | 2007-08-20 21:36:30 +0900 | [diff] [blame] | 716 | parent_sd = &sysfs_root; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 717 | |
Tejun Heo | 608e266 | 2007-06-14 04:27:22 +0900 | [diff] [blame] | 718 | error = create_dir(kobj, parent_sd, kobject_name(kobj), &sd); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 719 | if (!error) |
Tejun Heo | 608e266 | 2007-06-14 04:27:22 +0900 | [diff] [blame] | 720 | kobj->sd = sd; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 721 | return error; |
| 722 | } |
| 723 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 724 | static struct dentry * sysfs_lookup(struct inode *dir, struct dentry *dentry, |
| 725 | struct nameidata *nd) |
| 726 | { |
Tejun Heo | 6cb5214 | 2007-07-31 19:15:08 +0900 | [diff] [blame] | 727 | struct dentry *ret = NULL; |
Tejun Heo | a7a0475 | 2007-08-02 21:38:02 +0900 | [diff] [blame] | 728 | struct sysfs_dirent *parent_sd = dentry->d_parent->d_fsdata; |
| 729 | struct sysfs_dirent *sd; |
Tejun Heo | fc9f54b | 2007-06-14 03:45:17 +0900 | [diff] [blame] | 730 | struct inode *inode; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 731 | |
Tejun Heo | 6cb5214 | 2007-07-31 19:15:08 +0900 | [diff] [blame] | 732 | mutex_lock(&sysfs_mutex); |
| 733 | |
Eric W. Biederman | 94777e0 | 2007-08-20 21:36:30 +0900 | [diff] [blame] | 734 | sd = sysfs_find_dirent(parent_sd, dentry->d_name.name); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 735 | |
Tejun Heo | fc9f54b | 2007-06-14 03:45:17 +0900 | [diff] [blame] | 736 | /* no such entry */ |
Tejun Heo | e49452c | 2008-01-16 12:06:14 +0900 | [diff] [blame] | 737 | if (!sd) { |
| 738 | ret = ERR_PTR(-ENOENT); |
Tejun Heo | 6cb5214 | 2007-07-31 19:15:08 +0900 | [diff] [blame] | 739 | goto out_unlock; |
Tejun Heo | e49452c | 2008-01-16 12:06:14 +0900 | [diff] [blame] | 740 | } |
Tejun Heo | fc9f54b | 2007-06-14 03:45:17 +0900 | [diff] [blame] | 741 | |
| 742 | /* attach dentry and inode */ |
Tejun Heo | 8312a8d | 2007-06-14 03:45:17 +0900 | [diff] [blame] | 743 | inode = sysfs_get_inode(sd); |
Tejun Heo | 6cb5214 | 2007-07-31 19:15:08 +0900 | [diff] [blame] | 744 | if (!inode) { |
| 745 | ret = ERR_PTR(-ENOMEM); |
| 746 | goto out_unlock; |
| 747 | } |
Tejun Heo | 3007e99 | 2007-06-14 04:27:23 +0900 | [diff] [blame] | 748 | |
Tejun Heo | d6b4fd2 | 2007-09-20 16:05:11 +0900 | [diff] [blame] | 749 | /* instantiate and hash dentry */ |
| 750 | dentry->d_op = &sysfs_dentry_ops; |
| 751 | dentry->d_fsdata = sysfs_get(sd); |
Eric W. Biederman | 119dd52 | 2007-08-20 21:36:29 +0900 | [diff] [blame] | 752 | d_instantiate(dentry, inode); |
Tejun Heo | d6b4fd2 | 2007-09-20 16:05:11 +0900 | [diff] [blame] | 753 | d_rehash(dentry); |
Tejun Heo | fc9f54b | 2007-06-14 03:45:17 +0900 | [diff] [blame] | 754 | |
Tejun Heo | 6cb5214 | 2007-07-31 19:15:08 +0900 | [diff] [blame] | 755 | out_unlock: |
Tejun Heo | 3007e99 | 2007-06-14 04:27:23 +0900 | [diff] [blame] | 756 | mutex_unlock(&sysfs_mutex); |
Tejun Heo | 6cb5214 | 2007-07-31 19:15:08 +0900 | [diff] [blame] | 757 | return ret; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 758 | } |
| 759 | |
Arjan van de Ven | c5ef1c4 | 2007-02-12 00:55:40 -0800 | [diff] [blame] | 760 | const struct inode_operations sysfs_dir_inode_operations = { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 761 | .lookup = sysfs_lookup, |
Maneesh Soni | 988d186 | 2005-05-31 10:39:14 +0530 | [diff] [blame] | 762 | .setattr = sysfs_setattr, |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 763 | }; |
| 764 | |
Tejun Heo | 608e266 | 2007-06-14 04:27:22 +0900 | [diff] [blame] | 765 | static void remove_dir(struct sysfs_dirent *sd) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 766 | { |
Tejun Heo | fb6896d | 2007-06-14 04:27:24 +0900 | [diff] [blame] | 767 | struct sysfs_addrm_cxt acxt; |
| 768 | |
| 769 | sysfs_addrm_start(&acxt, sd->s_parent); |
Tejun Heo | fb6896d | 2007-06-14 04:27:24 +0900 | [diff] [blame] | 770 | sysfs_remove_one(&acxt, sd); |
| 771 | sysfs_addrm_finish(&acxt); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 772 | } |
| 773 | |
Tejun Heo | 608e266 | 2007-06-14 04:27:22 +0900 | [diff] [blame] | 774 | void sysfs_remove_subdir(struct sysfs_dirent *sd) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 775 | { |
Tejun Heo | 608e266 | 2007-06-14 04:27:22 +0900 | [diff] [blame] | 776 | remove_dir(sd); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 777 | } |
| 778 | |
| 779 | |
Tejun Heo | 608e266 | 2007-06-14 04:27:22 +0900 | [diff] [blame] | 780 | static void __sysfs_remove_dir(struct sysfs_dirent *dir_sd) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 781 | { |
Tejun Heo | fb6896d | 2007-06-14 04:27:24 +0900 | [diff] [blame] | 782 | struct sysfs_addrm_cxt acxt; |
Tejun Heo | 0c73f18 | 2007-06-14 03:45:18 +0900 | [diff] [blame] | 783 | struct sysfs_dirent **pos; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 784 | |
Tejun Heo | 608e266 | 2007-06-14 04:27:22 +0900 | [diff] [blame] | 785 | if (!dir_sd) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 786 | return; |
| 787 | |
Tejun Heo | 608e266 | 2007-06-14 04:27:22 +0900 | [diff] [blame] | 788 | pr_debug("sysfs %s: removing dir\n", dir_sd->s_name); |
Tejun Heo | fb6896d | 2007-06-14 04:27:24 +0900 | [diff] [blame] | 789 | sysfs_addrm_start(&acxt, dir_sd); |
Tejun Heo | bc747f3 | 2007-09-20 16:05:12 +0900 | [diff] [blame] | 790 | pos = &dir_sd->s_dir.children; |
Tejun Heo | 0c73f18 | 2007-06-14 03:45:18 +0900 | [diff] [blame] | 791 | while (*pos) { |
| 792 | struct sysfs_dirent *sd = *pos; |
| 793 | |
Eric W. Biederman | 3efa65b | 2007-08-20 21:36:30 +0900 | [diff] [blame] | 794 | if (sysfs_type(sd) != SYSFS_DIR) |
Tejun Heo | fb6896d | 2007-06-14 04:27:24 +0900 | [diff] [blame] | 795 | sysfs_remove_one(&acxt, sd); |
Tejun Heo | 41fc1c2 | 2007-08-02 21:38:03 +0900 | [diff] [blame] | 796 | else |
Tejun Heo | 0c73f18 | 2007-06-14 03:45:18 +0900 | [diff] [blame] | 797 | pos = &(*pos)->s_sibling; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 798 | } |
Tejun Heo | fb6896d | 2007-06-14 04:27:24 +0900 | [diff] [blame] | 799 | sysfs_addrm_finish(&acxt); |
Tejun Heo | 0ab6608 | 2007-06-14 03:45:16 +0900 | [diff] [blame] | 800 | |
Tejun Heo | 608e266 | 2007-06-14 04:27:22 +0900 | [diff] [blame] | 801 | remove_dir(dir_sd); |
Eric W. Biederman | b592fcf | 2007-01-24 12:35:52 -0700 | [diff] [blame] | 802 | } |
| 803 | |
| 804 | /** |
| 805 | * sysfs_remove_dir - remove an object's directory. |
| 806 | * @kobj: object. |
| 807 | * |
| 808 | * The only thing special about this is that we remove any files in |
| 809 | * the directory before we remove the directory, and we've inlined |
| 810 | * what used to be sysfs_rmdir() below, instead of calling separately. |
| 811 | */ |
| 812 | |
| 813 | void sysfs_remove_dir(struct kobject * kobj) |
| 814 | { |
Tejun Heo | 608e266 | 2007-06-14 04:27:22 +0900 | [diff] [blame] | 815 | struct sysfs_dirent *sd = kobj->sd; |
Tejun Heo | aecdced | 2007-06-14 03:45:15 +0900 | [diff] [blame] | 816 | |
Tejun Heo | 5f99532 | 2007-06-14 04:27:23 +0900 | [diff] [blame] | 817 | spin_lock(&sysfs_assoc_lock); |
Tejun Heo | 608e266 | 2007-06-14 04:27:22 +0900 | [diff] [blame] | 818 | kobj->sd = NULL; |
Tejun Heo | 5f99532 | 2007-06-14 04:27:23 +0900 | [diff] [blame] | 819 | spin_unlock(&sysfs_assoc_lock); |
Tejun Heo | aecdced | 2007-06-14 03:45:15 +0900 | [diff] [blame] | 820 | |
Tejun Heo | 608e266 | 2007-06-14 04:27:22 +0900 | [diff] [blame] | 821 | __sysfs_remove_dir(sd); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 822 | } |
| 823 | |
Eric W. Biederman | 90bc613 | 2007-07-31 19:15:08 +0900 | [diff] [blame] | 824 | int sysfs_rename_dir(struct kobject * kobj, const char *new_name) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 825 | { |
Eric W. Biederman | 9918f9a | 2007-08-20 21:36:31 +0900 | [diff] [blame] | 826 | struct sysfs_dirent *sd = kobj->sd; |
Eric W. Biederman | 90bc613 | 2007-07-31 19:15:08 +0900 | [diff] [blame] | 827 | struct dentry *parent = NULL; |
Tejun Heo | 5122503 | 2007-06-14 04:27:25 +0900 | [diff] [blame] | 828 | struct dentry *old_dentry = NULL, *new_dentry = NULL; |
| 829 | const char *dup_name = NULL; |
Tejun Heo | 996b737 | 2007-06-14 03:45:14 +0900 | [diff] [blame] | 830 | int error; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 831 | |
Eric W. Biederman | 932ea2e | 2007-08-20 21:36:30 +0900 | [diff] [blame] | 832 | mutex_lock(&sysfs_rename_mutex); |
| 833 | |
Eric W. Biederman | 9918f9a | 2007-08-20 21:36:31 +0900 | [diff] [blame] | 834 | error = 0; |
| 835 | if (strcmp(sd->s_name, new_name) == 0) |
| 836 | goto out; /* nothing to rename */ |
| 837 | |
Tejun Heo | ff869de | 2007-08-02 21:38:02 +0900 | [diff] [blame] | 838 | /* get the original dentry */ |
Tejun Heo | 5122503 | 2007-06-14 04:27:25 +0900 | [diff] [blame] | 839 | old_dentry = sysfs_get_dentry(sd); |
| 840 | if (IS_ERR(old_dentry)) { |
| 841 | error = PTR_ERR(old_dentry); |
Tejun Heo | 456ef15 | 2008-01-16 12:10:53 +0900 | [diff] [blame] | 842 | old_dentry = NULL; |
Eric W. Biederman | 9918f9a | 2007-08-20 21:36:31 +0900 | [diff] [blame] | 843 | goto out; |
Tejun Heo | 5122503 | 2007-06-14 04:27:25 +0900 | [diff] [blame] | 844 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 845 | |
Tejun Heo | ff869de | 2007-08-02 21:38:02 +0900 | [diff] [blame] | 846 | parent = old_dentry->d_parent; |
Tejun Heo | 5122503 | 2007-06-14 04:27:25 +0900 | [diff] [blame] | 847 | |
Eric W. Biederman | 90bc613 | 2007-07-31 19:15:08 +0900 | [diff] [blame] | 848 | /* lock parent and get dentry for new name */ |
| 849 | mutex_lock(&parent->d_inode->i_mutex); |
Eric W. Biederman | 9918f9a | 2007-08-20 21:36:31 +0900 | [diff] [blame] | 850 | mutex_lock(&sysfs_mutex); |
Tejun Heo | 996b737 | 2007-06-14 03:45:14 +0900 | [diff] [blame] | 851 | |
| 852 | error = -EEXIST; |
Eric W. Biederman | 9918f9a | 2007-08-20 21:36:31 +0900 | [diff] [blame] | 853 | if (sysfs_find_dirent(sd->s_parent, new_name)) |
| 854 | goto out_unlock; |
| 855 | |
| 856 | error = -ENOMEM; |
| 857 | new_dentry = d_alloc_name(parent, new_name); |
| 858 | if (!new_dentry) |
Tejun Heo | 5122503 | 2007-06-14 04:27:25 +0900 | [diff] [blame] | 859 | goto out_unlock; |
Tejun Heo | 996b737 | 2007-06-14 03:45:14 +0900 | [diff] [blame] | 860 | |
Eric W. Biederman | 0b4a4fe | 2008-07-03 18:05:28 -0700 | [diff] [blame] | 861 | /* rename sysfs_dirent */ |
Tejun Heo | 0c096b5 | 2007-06-14 03:45:15 +0900 | [diff] [blame] | 862 | error = -ENOMEM; |
| 863 | new_name = dup_name = kstrdup(new_name, GFP_KERNEL); |
| 864 | if (!new_name) |
Eric W. Biederman | 9918f9a | 2007-08-20 21:36:31 +0900 | [diff] [blame] | 865 | goto out_unlock; |
Tejun Heo | 996b737 | 2007-06-14 03:45:14 +0900 | [diff] [blame] | 866 | |
Tejun Heo | 5122503 | 2007-06-14 04:27:25 +0900 | [diff] [blame] | 867 | dup_name = sd->s_name; |
Tejun Heo | 0c096b5 | 2007-06-14 03:45:15 +0900 | [diff] [blame] | 868 | sd->s_name = new_name; |
| 869 | |
Tejun Heo | ff869de | 2007-08-02 21:38:02 +0900 | [diff] [blame] | 870 | /* rename */ |
Tejun Heo | 996b737 | 2007-06-14 03:45:14 +0900 | [diff] [blame] | 871 | d_add(new_dentry, NULL); |
Eric W. Biederman | 5a26b79 | 2007-08-20 21:36:30 +0900 | [diff] [blame] | 872 | d_move(old_dentry, new_dentry); |
Tejun Heo | 996b737 | 2007-06-14 03:45:14 +0900 | [diff] [blame] | 873 | |
Tejun Heo | 996b737 | 2007-06-14 03:45:14 +0900 | [diff] [blame] | 874 | error = 0; |
Tejun Heo | 996b737 | 2007-06-14 03:45:14 +0900 | [diff] [blame] | 875 | out_unlock: |
Eric W. Biederman | 9918f9a | 2007-08-20 21:36:31 +0900 | [diff] [blame] | 876 | mutex_unlock(&sysfs_mutex); |
Eric W. Biederman | 90bc613 | 2007-07-31 19:15:08 +0900 | [diff] [blame] | 877 | mutex_unlock(&parent->d_inode->i_mutex); |
Tejun Heo | 5122503 | 2007-06-14 04:27:25 +0900 | [diff] [blame] | 878 | kfree(dup_name); |
Tejun Heo | 5122503 | 2007-06-14 04:27:25 +0900 | [diff] [blame] | 879 | dput(old_dentry); |
| 880 | dput(new_dentry); |
Eric W. Biederman | 9918f9a | 2007-08-20 21:36:31 +0900 | [diff] [blame] | 881 | out: |
Eric W. Biederman | 932ea2e | 2007-08-20 21:36:30 +0900 | [diff] [blame] | 882 | mutex_unlock(&sysfs_rename_mutex); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 883 | return error; |
| 884 | } |
| 885 | |
Tejun Heo | 5122503 | 2007-06-14 04:27:25 +0900 | [diff] [blame] | 886 | int sysfs_move_dir(struct kobject *kobj, struct kobject *new_parent_kobj) |
Cornelia Huck | 8a82472 | 2006-11-20 17:07:51 +0100 | [diff] [blame] | 887 | { |
Tejun Heo | 5122503 | 2007-06-14 04:27:25 +0900 | [diff] [blame] | 888 | struct sysfs_dirent *sd = kobj->sd; |
| 889 | struct sysfs_dirent *new_parent_sd; |
| 890 | struct dentry *old_parent, *new_parent = NULL; |
| 891 | struct dentry *old_dentry = NULL, *new_dentry = NULL; |
Cornelia Huck | 8a82472 | 2006-11-20 17:07:51 +0100 | [diff] [blame] | 892 | int error; |
| 893 | |
Eric W. Biederman | 932ea2e | 2007-08-20 21:36:30 +0900 | [diff] [blame] | 894 | mutex_lock(&sysfs_rename_mutex); |
Tejun Heo | 5122503 | 2007-06-14 04:27:25 +0900 | [diff] [blame] | 895 | BUG_ON(!sd->s_parent); |
| 896 | 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] | 897 | |
Eric W. Biederman | 45aaae9 | 2007-08-20 21:36:31 +0900 | [diff] [blame] | 898 | error = 0; |
| 899 | if (sd->s_parent == new_parent_sd) |
| 900 | goto out; /* nothing to move */ |
| 901 | |
Tejun Heo | 5122503 | 2007-06-14 04:27:25 +0900 | [diff] [blame] | 902 | /* get dentries */ |
| 903 | old_dentry = sysfs_get_dentry(sd); |
| 904 | if (IS_ERR(old_dentry)) { |
| 905 | error = PTR_ERR(old_dentry); |
Tejun Heo | 456ef15 | 2008-01-16 12:10:53 +0900 | [diff] [blame] | 906 | old_dentry = NULL; |
Eric W. Biederman | 45aaae9 | 2007-08-20 21:36:31 +0900 | [diff] [blame] | 907 | goto out; |
Tejun Heo | 5122503 | 2007-06-14 04:27:25 +0900 | [diff] [blame] | 908 | } |
Eric W. Biederman | 5a26b79 | 2007-08-20 21:36:30 +0900 | [diff] [blame] | 909 | old_parent = old_dentry->d_parent; |
Tejun Heo | 5122503 | 2007-06-14 04:27:25 +0900 | [diff] [blame] | 910 | |
| 911 | new_parent = sysfs_get_dentry(new_parent_sd); |
| 912 | if (IS_ERR(new_parent)) { |
| 913 | error = PTR_ERR(new_parent); |
Tejun Heo | 456ef15 | 2008-01-16 12:10:53 +0900 | [diff] [blame] | 914 | new_parent = NULL; |
Eric W. Biederman | 45aaae9 | 2007-08-20 21:36:31 +0900 | [diff] [blame] | 915 | goto out; |
Tejun Heo | 5122503 | 2007-06-14 04:27:25 +0900 | [diff] [blame] | 916 | } |
| 917 | |
Cornelia Huck | 8a82472 | 2006-11-20 17:07:51 +0100 | [diff] [blame] | 918 | again: |
Tejun Heo | 5122503 | 2007-06-14 04:27:25 +0900 | [diff] [blame] | 919 | mutex_lock(&old_parent->d_inode->i_mutex); |
| 920 | if (!mutex_trylock(&new_parent->d_inode->i_mutex)) { |
| 921 | mutex_unlock(&old_parent->d_inode->i_mutex); |
Cornelia Huck | 8a82472 | 2006-11-20 17:07:51 +0100 | [diff] [blame] | 922 | goto again; |
| 923 | } |
Eric W. Biederman | 45aaae9 | 2007-08-20 21:36:31 +0900 | [diff] [blame] | 924 | mutex_lock(&sysfs_mutex); |
Cornelia Huck | 8a82472 | 2006-11-20 17:07:51 +0100 | [diff] [blame] | 925 | |
Eric W. Biederman | 45aaae9 | 2007-08-20 21:36:31 +0900 | [diff] [blame] | 926 | error = -EEXIST; |
| 927 | if (sysfs_find_dirent(new_parent_sd, sd->s_name)) |
Tejun Heo | 5122503 | 2007-06-14 04:27:25 +0900 | [diff] [blame] | 928 | goto out_unlock; |
Eric W. Biederman | 45aaae9 | 2007-08-20 21:36:31 +0900 | [diff] [blame] | 929 | |
| 930 | error = -ENOMEM; |
| 931 | new_dentry = d_alloc_name(new_parent, sd->s_name); |
| 932 | if (!new_dentry) |
| 933 | goto out_unlock; |
| 934 | |
| 935 | error = 0; |
Cornelia Huck | 8a82472 | 2006-11-20 17:07:51 +0100 | [diff] [blame] | 936 | d_add(new_dentry, NULL); |
Eric W. Biederman | 5a26b79 | 2007-08-20 21:36:30 +0900 | [diff] [blame] | 937 | d_move(old_dentry, new_dentry); |
Cornelia Huck | 8a82472 | 2006-11-20 17:07:51 +0100 | [diff] [blame] | 938 | |
| 939 | /* 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] | 940 | sysfs_unlink_sibling(sd); |
Tejun Heo | 7f7cfff | 2007-06-14 03:45:17 +0900 | [diff] [blame] | 941 | sysfs_get(new_parent_sd); |
| 942 | sysfs_put(sd->s_parent); |
| 943 | sd->s_parent = new_parent_sd; |
Tejun Heo | 0c73f18 | 2007-06-14 03:45:18 +0900 | [diff] [blame] | 944 | sysfs_link_sibling(sd); |
Cornelia Huck | 8a82472 | 2006-11-20 17:07:51 +0100 | [diff] [blame] | 945 | |
Tejun Heo | 5122503 | 2007-06-14 04:27:25 +0900 | [diff] [blame] | 946 | out_unlock: |
Eric W. Biederman | 45aaae9 | 2007-08-20 21:36:31 +0900 | [diff] [blame] | 947 | mutex_unlock(&sysfs_mutex); |
Tejun Heo | 5122503 | 2007-06-14 04:27:25 +0900 | [diff] [blame] | 948 | mutex_unlock(&new_parent->d_inode->i_mutex); |
| 949 | mutex_unlock(&old_parent->d_inode->i_mutex); |
Eric W. Biederman | 45aaae9 | 2007-08-20 21:36:31 +0900 | [diff] [blame] | 950 | out: |
Tejun Heo | 5122503 | 2007-06-14 04:27:25 +0900 | [diff] [blame] | 951 | dput(new_parent); |
| 952 | dput(old_dentry); |
| 953 | dput(new_dentry); |
Eric W. Biederman | 932ea2e | 2007-08-20 21:36:30 +0900 | [diff] [blame] | 954 | mutex_unlock(&sysfs_rename_mutex); |
Cornelia Huck | 8a82472 | 2006-11-20 17:07:51 +0100 | [diff] [blame] | 955 | return error; |
| 956 | } |
| 957 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 958 | /* Relationship between s_mode and the DT_xxx types */ |
| 959 | static inline unsigned char dt_type(struct sysfs_dirent *sd) |
| 960 | { |
| 961 | return (sd->s_mode >> 12) & 15; |
| 962 | } |
| 963 | |
| 964 | static int sysfs_readdir(struct file * filp, void * dirent, filldir_t filldir) |
| 965 | { |
Josef "Jeff" Sipek | f427f5d | 2006-12-08 02:36:36 -0800 | [diff] [blame] | 966 | struct dentry *dentry = filp->f_path.dentry; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 967 | struct sysfs_dirent * parent_sd = dentry->d_fsdata; |
Eric W. Biederman | 3efa65b | 2007-08-20 21:36:30 +0900 | [diff] [blame] | 968 | struct sysfs_dirent *pos; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 969 | ino_t ino; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 970 | |
Eric W. Biederman | 3efa65b | 2007-08-20 21:36:30 +0900 | [diff] [blame] | 971 | if (filp->f_pos == 0) { |
| 972 | ino = parent_sd->s_ino; |
| 973 | if (filldir(dirent, ".", 1, filp->f_pos, ino, DT_DIR) == 0) |
| 974 | filp->f_pos++; |
| 975 | } |
| 976 | if (filp->f_pos == 1) { |
| 977 | if (parent_sd->s_parent) |
| 978 | ino = parent_sd->s_parent->s_ino; |
| 979 | else |
Eric Sandeen | dc35125 | 2007-06-11 14:02:45 +0900 | [diff] [blame] | 980 | ino = parent_sd->s_ino; |
Eric W. Biederman | 3efa65b | 2007-08-20 21:36:30 +0900 | [diff] [blame] | 981 | if (filldir(dirent, "..", 2, filp->f_pos, ino, DT_DIR) == 0) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 982 | filp->f_pos++; |
Eric W. Biederman | 3efa65b | 2007-08-20 21:36:30 +0900 | [diff] [blame] | 983 | } |
| 984 | if ((filp->f_pos > 1) && (filp->f_pos < INT_MAX)) { |
| 985 | mutex_lock(&sysfs_mutex); |
| 986 | |
| 987 | /* Skip the dentries we have already reported */ |
Tejun Heo | bc747f3 | 2007-09-20 16:05:12 +0900 | [diff] [blame] | 988 | pos = parent_sd->s_dir.children; |
Eric W. Biederman | 3efa65b | 2007-08-20 21:36:30 +0900 | [diff] [blame] | 989 | while (pos && (filp->f_pos > pos->s_ino)) |
| 990 | pos = pos->s_sibling; |
| 991 | |
| 992 | for ( ; pos; pos = pos->s_sibling) { |
| 993 | const char * name; |
| 994 | int len; |
| 995 | |
| 996 | name = pos->s_name; |
| 997 | len = strlen(name); |
| 998 | filp->f_pos = ino = pos->s_ino; |
| 999 | |
| 1000 | if (filldir(dirent, name, len, filp->f_pos, ino, |
| 1001 | dt_type(pos)) < 0) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1002 | break; |
Eric W. Biederman | 3efa65b | 2007-08-20 21:36:30 +0900 | [diff] [blame] | 1003 | } |
| 1004 | if (!pos) |
| 1005 | filp->f_pos = INT_MAX; |
| 1006 | mutex_unlock(&sysfs_mutex); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1007 | } |
| 1008 | return 0; |
| 1009 | } |
| 1010 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1011 | |
Arjan van de Ven | 4b6f5d2 | 2006-03-28 01:56:42 -0800 | [diff] [blame] | 1012 | const struct file_operations sysfs_dir_operations = { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1013 | .read = generic_read_dir, |
| 1014 | .readdir = sysfs_readdir, |
Christoph Hellwig | 3222a3e | 2008-09-03 21:53:01 +0200 | [diff] [blame] | 1015 | .llseek = generic_file_llseek, |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1016 | }; |