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> |
Eric W. Biederman | 4c3da22 | 2009-11-04 02:50:06 -0800 | [diff] [blame] | 24 | #include <linux/security.h> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 25 | #include "sysfs.h" |
| 26 | |
Tejun Heo | 3007e99 | 2007-06-14 04:27:23 +0900 | [diff] [blame] | 27 | DEFINE_MUTEX(sysfs_mutex); |
Eric W. Biederman | 932ea2e | 2007-08-20 21:36:30 +0900 | [diff] [blame] | 28 | DEFINE_MUTEX(sysfs_rename_mutex); |
Roel Kluin | f7a75f0 | 2007-10-16 23:30:25 -0700 | [diff] [blame] | 29 | DEFINE_SPINLOCK(sysfs_assoc_lock); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 30 | |
Roel Kluin | f7a75f0 | 2007-10-16 23:30:25 -0700 | [diff] [blame] | 31 | static DEFINE_SPINLOCK(sysfs_ino_lock); |
Tejun Heo | 2b611bb | 2007-06-14 03:45:13 +0900 | [diff] [blame] | 32 | static DEFINE_IDA(sysfs_ino_ida); |
| 33 | |
Tejun Heo | b6b4a43 | 2007-06-14 03:45:18 +0900 | [diff] [blame] | 34 | /** |
Tejun Heo | 0c73f18 | 2007-06-14 03:45:18 +0900 | [diff] [blame] | 35 | * sysfs_link_sibling - link sysfs_dirent into sibling list |
| 36 | * @sd: sysfs_dirent of interest |
| 37 | * |
| 38 | * Link @sd into its sibling list which starts from |
Tejun Heo | bc747f3 | 2007-09-20 16:05:12 +0900 | [diff] [blame] | 39 | * sd->s_parent->s_dir.children. |
Tejun Heo | 0c73f18 | 2007-06-14 03:45:18 +0900 | [diff] [blame] | 40 | * |
| 41 | * Locking: |
Tejun Heo | 3007e99 | 2007-06-14 04:27:23 +0900 | [diff] [blame] | 42 | * mutex_lock(sysfs_mutex) |
Tejun Heo | 0c73f18 | 2007-06-14 03:45:18 +0900 | [diff] [blame] | 43 | */ |
Tejun Heo | 41fc1c2 | 2007-08-02 21:38:03 +0900 | [diff] [blame] | 44 | static void sysfs_link_sibling(struct sysfs_dirent *sd) |
Tejun Heo | 0c73f18 | 2007-06-14 03:45:18 +0900 | [diff] [blame] | 45 | { |
| 46 | struct sysfs_dirent *parent_sd = sd->s_parent; |
Eric W. Biederman | 3efa65b | 2007-08-20 21:36:30 +0900 | [diff] [blame] | 47 | struct sysfs_dirent **pos; |
Tejun Heo | 0c73f18 | 2007-06-14 03:45:18 +0900 | [diff] [blame] | 48 | |
| 49 | BUG_ON(sd->s_sibling); |
Eric W. Biederman | 3efa65b | 2007-08-20 21:36:30 +0900 | [diff] [blame] | 50 | |
| 51 | /* Store directory entries in order by ino. This allows |
| 52 | * readdir to properly restart without having to add a |
Tejun Heo | bc747f3 | 2007-09-20 16:05:12 +0900 | [diff] [blame] | 53 | * cursor into the s_dir.children list. |
Eric W. Biederman | 3efa65b | 2007-08-20 21:36:30 +0900 | [diff] [blame] | 54 | */ |
Tejun Heo | bc747f3 | 2007-09-20 16:05:12 +0900 | [diff] [blame] | 55 | 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] | 56 | if (sd->s_ino < (*pos)->s_ino) |
| 57 | break; |
| 58 | } |
| 59 | sd->s_sibling = *pos; |
| 60 | *pos = sd; |
Tejun Heo | 0c73f18 | 2007-06-14 03:45:18 +0900 | [diff] [blame] | 61 | } |
| 62 | |
| 63 | /** |
| 64 | * sysfs_unlink_sibling - unlink sysfs_dirent from sibling list |
| 65 | * @sd: sysfs_dirent of interest |
| 66 | * |
| 67 | * Unlink @sd from its sibling list which starts from |
Tejun Heo | bc747f3 | 2007-09-20 16:05:12 +0900 | [diff] [blame] | 68 | * sd->s_parent->s_dir.children. |
Tejun Heo | 0c73f18 | 2007-06-14 03:45:18 +0900 | [diff] [blame] | 69 | * |
| 70 | * Locking: |
Tejun Heo | 3007e99 | 2007-06-14 04:27:23 +0900 | [diff] [blame] | 71 | * mutex_lock(sysfs_mutex) |
Tejun Heo | 0c73f18 | 2007-06-14 03:45:18 +0900 | [diff] [blame] | 72 | */ |
Tejun Heo | 41fc1c2 | 2007-08-02 21:38:03 +0900 | [diff] [blame] | 73 | static void sysfs_unlink_sibling(struct sysfs_dirent *sd) |
Tejun Heo | 0c73f18 | 2007-06-14 03:45:18 +0900 | [diff] [blame] | 74 | { |
| 75 | struct sysfs_dirent **pos; |
| 76 | |
Tejun Heo | bc747f3 | 2007-09-20 16:05:12 +0900 | [diff] [blame] | 77 | for (pos = &sd->s_parent->s_dir.children; *pos; |
| 78 | pos = &(*pos)->s_sibling) { |
Tejun Heo | 0c73f18 | 2007-06-14 03:45:18 +0900 | [diff] [blame] | 79 | if (*pos == sd) { |
| 80 | *pos = sd->s_sibling; |
| 81 | sd->s_sibling = NULL; |
| 82 | break; |
| 83 | } |
| 84 | } |
| 85 | } |
| 86 | |
| 87 | /** |
Tejun Heo | 53e0ae9 | 2007-06-14 04:27:25 +0900 | [diff] [blame] | 88 | * sysfs_get_dentry - get dentry for the given sysfs_dirent |
| 89 | * @sd: sysfs_dirent of interest |
| 90 | * |
| 91 | * Get dentry for @sd. Dentry is looked up if currently not |
Tejun Heo | e0712bb | 2007-08-20 21:36:30 +0900 | [diff] [blame] | 92 | * present. This function descends from the root looking up |
| 93 | * dentry for each step. |
Tejun Heo | 53e0ae9 | 2007-06-14 04:27:25 +0900 | [diff] [blame] | 94 | * |
| 95 | * LOCKING: |
Eric W. Biederman | 932ea2e | 2007-08-20 21:36:30 +0900 | [diff] [blame] | 96 | * mutex_lock(sysfs_rename_mutex) |
Tejun Heo | 53e0ae9 | 2007-06-14 04:27:25 +0900 | [diff] [blame] | 97 | * |
| 98 | * RETURNS: |
| 99 | * Pointer to found dentry on success, ERR_PTR() value on error. |
| 100 | */ |
| 101 | struct dentry *sysfs_get_dentry(struct sysfs_dirent *sd) |
| 102 | { |
Tejun Heo | e0712bb | 2007-08-20 21:36:30 +0900 | [diff] [blame] | 103 | struct dentry *dentry = dget(sysfs_sb->s_root); |
Tejun Heo | 53e0ae9 | 2007-06-14 04:27:25 +0900 | [diff] [blame] | 104 | |
Tejun Heo | e0712bb | 2007-08-20 21:36:30 +0900 | [diff] [blame] | 105 | while (dentry->d_fsdata != sd) { |
| 106 | struct sysfs_dirent *cur; |
| 107 | struct dentry *parent; |
Tejun Heo | 53e0ae9 | 2007-06-14 04:27:25 +0900 | [diff] [blame] | 108 | |
Tejun Heo | e0712bb | 2007-08-20 21:36:30 +0900 | [diff] [blame] | 109 | /* find the first ancestor which hasn't been looked up */ |
| 110 | cur = sd; |
| 111 | while (cur->s_parent != dentry->d_fsdata) |
Tejun Heo | 53e0ae9 | 2007-06-14 04:27:25 +0900 | [diff] [blame] | 112 | cur = cur->s_parent; |
| 113 | |
Tejun Heo | 53e0ae9 | 2007-06-14 04:27:25 +0900 | [diff] [blame] | 114 | /* look it up */ |
Tejun Heo | e0712bb | 2007-08-20 21:36:30 +0900 | [diff] [blame] | 115 | parent = dentry; |
| 116 | mutex_lock(&parent->d_inode->i_mutex); |
Christoph Hellwig | eead191 | 2007-10-16 23:25:38 -0700 | [diff] [blame] | 117 | dentry = lookup_one_noperm(cur->s_name, parent); |
Tejun Heo | e0712bb | 2007-08-20 21:36:30 +0900 | [diff] [blame] | 118 | mutex_unlock(&parent->d_inode->i_mutex); |
| 119 | dput(parent); |
Tejun Heo | 53e0ae9 | 2007-06-14 04:27:25 +0900 | [diff] [blame] | 120 | |
Tejun Heo | e0712bb | 2007-08-20 21:36:30 +0900 | [diff] [blame] | 121 | if (IS_ERR(dentry)) |
| 122 | break; |
Tejun Heo | 53e0ae9 | 2007-06-14 04:27:25 +0900 | [diff] [blame] | 123 | } |
Tejun Heo | 53e0ae9 | 2007-06-14 04:27:25 +0900 | [diff] [blame] | 124 | return dentry; |
| 125 | } |
| 126 | |
| 127 | /** |
Tejun Heo | b6b4a43 | 2007-06-14 03:45:18 +0900 | [diff] [blame] | 128 | * sysfs_get_active - get an active reference to sysfs_dirent |
| 129 | * @sd: sysfs_dirent to get an active reference to |
| 130 | * |
| 131 | * Get an active reference of @sd. This function is noop if @sd |
| 132 | * is NULL. |
| 133 | * |
| 134 | * RETURNS: |
| 135 | * Pointer to @sd on success, NULL on failure. |
| 136 | */ |
Adrian Bunk | 78e9d36 | 2007-10-24 18:23:32 +0200 | [diff] [blame] | 137 | static struct sysfs_dirent *sysfs_get_active(struct sysfs_dirent *sd) |
Tejun Heo | b6b4a43 | 2007-06-14 03:45:18 +0900 | [diff] [blame] | 138 | { |
Tejun Heo | 8619f97 | 2007-06-14 03:45:18 +0900 | [diff] [blame] | 139 | if (unlikely(!sd)) |
| 140 | return NULL; |
| 141 | |
| 142 | while (1) { |
| 143 | int v, t; |
| 144 | |
| 145 | v = atomic_read(&sd->s_active); |
| 146 | if (unlikely(v < 0)) |
| 147 | return NULL; |
| 148 | |
| 149 | t = atomic_cmpxchg(&sd->s_active, v, v + 1); |
| 150 | if (likely(t == v)) |
| 151 | return sd; |
| 152 | if (t < 0) |
| 153 | return NULL; |
| 154 | |
| 155 | cpu_relax(); |
Tejun Heo | b6b4a43 | 2007-06-14 03:45:18 +0900 | [diff] [blame] | 156 | } |
Tejun Heo | b6b4a43 | 2007-06-14 03:45:18 +0900 | [diff] [blame] | 157 | } |
| 158 | |
| 159 | /** |
| 160 | * sysfs_put_active - put an active reference to sysfs_dirent |
| 161 | * @sd: sysfs_dirent to put an active reference to |
| 162 | * |
| 163 | * Put an active reference to @sd. This function is noop if @sd |
| 164 | * is NULL. |
| 165 | */ |
Adrian Bunk | 78e9d36 | 2007-10-24 18:23:32 +0200 | [diff] [blame] | 166 | static void sysfs_put_active(struct sysfs_dirent *sd) |
Tejun Heo | b6b4a43 | 2007-06-14 03:45:18 +0900 | [diff] [blame] | 167 | { |
Tejun Heo | 8619f97 | 2007-06-14 03:45:18 +0900 | [diff] [blame] | 168 | struct completion *cmpl; |
| 169 | int v; |
| 170 | |
| 171 | if (unlikely(!sd)) |
| 172 | return; |
| 173 | |
| 174 | v = atomic_dec_return(&sd->s_active); |
| 175 | if (likely(v != SD_DEACTIVATED_BIAS)) |
| 176 | return; |
| 177 | |
| 178 | /* atomic_dec_return() is a mb(), we'll always see the updated |
Tejun Heo | 0c73f18 | 2007-06-14 03:45:18 +0900 | [diff] [blame] | 179 | * sd->s_sibling. |
Tejun Heo | 8619f97 | 2007-06-14 03:45:18 +0900 | [diff] [blame] | 180 | */ |
Tejun Heo | 0c73f18 | 2007-06-14 03:45:18 +0900 | [diff] [blame] | 181 | cmpl = (void *)sd->s_sibling; |
Tejun Heo | 8619f97 | 2007-06-14 03:45:18 +0900 | [diff] [blame] | 182 | complete(cmpl); |
Tejun Heo | b6b4a43 | 2007-06-14 03:45:18 +0900 | [diff] [blame] | 183 | } |
| 184 | |
| 185 | /** |
| 186 | * sysfs_get_active_two - get active references to sysfs_dirent and parent |
| 187 | * @sd: sysfs_dirent of interest |
| 188 | * |
| 189 | * Get active reference to @sd and its parent. Parent's active |
| 190 | * reference is grabbed first. This function is noop if @sd is |
| 191 | * NULL. |
| 192 | * |
| 193 | * RETURNS: |
| 194 | * Pointer to @sd on success, NULL on failure. |
| 195 | */ |
| 196 | struct sysfs_dirent *sysfs_get_active_two(struct sysfs_dirent *sd) |
| 197 | { |
| 198 | if (sd) { |
| 199 | if (sd->s_parent && unlikely(!sysfs_get_active(sd->s_parent))) |
| 200 | return NULL; |
| 201 | if (unlikely(!sysfs_get_active(sd))) { |
| 202 | sysfs_put_active(sd->s_parent); |
| 203 | return NULL; |
| 204 | } |
| 205 | } |
| 206 | return sd; |
| 207 | } |
| 208 | |
| 209 | /** |
| 210 | * sysfs_put_active_two - put active references to sysfs_dirent and parent |
| 211 | * @sd: sysfs_dirent of interest |
| 212 | * |
| 213 | * Put active references to @sd and its parent. This function is |
| 214 | * noop if @sd is NULL. |
| 215 | */ |
| 216 | void sysfs_put_active_two(struct sysfs_dirent *sd) |
| 217 | { |
| 218 | if (sd) { |
| 219 | sysfs_put_active(sd); |
| 220 | sysfs_put_active(sd->s_parent); |
| 221 | } |
| 222 | } |
| 223 | |
| 224 | /** |
| 225 | * sysfs_deactivate - deactivate sysfs_dirent |
| 226 | * @sd: sysfs_dirent to deactivate |
| 227 | * |
Tejun Heo | 8619f97 | 2007-06-14 03:45:18 +0900 | [diff] [blame] | 228 | * Deny new active references and drain existing ones. |
Tejun Heo | b6b4a43 | 2007-06-14 03:45:18 +0900 | [diff] [blame] | 229 | */ |
Tejun Heo | fb6896d | 2007-06-14 04:27:24 +0900 | [diff] [blame] | 230 | static void sysfs_deactivate(struct sysfs_dirent *sd) |
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 | DECLARE_COMPLETION_ONSTACK(wait); |
| 233 | int v; |
Tejun Heo | b6b4a43 | 2007-06-14 03:45:18 +0900 | [diff] [blame] | 234 | |
Tejun Heo | 380e6fb | 2007-06-14 04:27:22 +0900 | [diff] [blame] | 235 | BUG_ON(sd->s_sibling || !(sd->s_flags & SYSFS_FLAG_REMOVED)); |
Tejun Heo | 0c73f18 | 2007-06-14 03:45:18 +0900 | [diff] [blame] | 236 | sd->s_sibling = (void *)&wait; |
Tejun Heo | 8619f97 | 2007-06-14 03:45:18 +0900 | [diff] [blame] | 237 | |
| 238 | /* atomic_add_return() is a mb(), put_active() will always see |
Tejun Heo | 0c73f18 | 2007-06-14 03:45:18 +0900 | [diff] [blame] | 239 | * the updated sd->s_sibling. |
Tejun Heo | b6b4a43 | 2007-06-14 03:45:18 +0900 | [diff] [blame] | 240 | */ |
Tejun Heo | 8619f97 | 2007-06-14 03:45:18 +0900 | [diff] [blame] | 241 | v = atomic_add_return(SD_DEACTIVATED_BIAS, &sd->s_active); |
| 242 | |
| 243 | if (v != SD_DEACTIVATED_BIAS) |
| 244 | wait_for_completion(&wait); |
| 245 | |
Tejun Heo | 0c73f18 | 2007-06-14 03:45:18 +0900 | [diff] [blame] | 246 | sd->s_sibling = NULL; |
Tejun Heo | b6b4a43 | 2007-06-14 03:45:18 +0900 | [diff] [blame] | 247 | } |
| 248 | |
Tejun Heo | 42b37df | 2007-06-14 03:45:17 +0900 | [diff] [blame] | 249 | static int sysfs_alloc_ino(ino_t *pino) |
Tejun Heo | 2b611bb | 2007-06-14 03:45:13 +0900 | [diff] [blame] | 250 | { |
| 251 | int ino, rc; |
| 252 | |
| 253 | retry: |
| 254 | spin_lock(&sysfs_ino_lock); |
| 255 | rc = ida_get_new_above(&sysfs_ino_ida, 2, &ino); |
| 256 | spin_unlock(&sysfs_ino_lock); |
| 257 | |
| 258 | if (rc == -EAGAIN) { |
| 259 | if (ida_pre_get(&sysfs_ino_ida, GFP_KERNEL)) |
| 260 | goto retry; |
| 261 | rc = -ENOMEM; |
| 262 | } |
| 263 | |
| 264 | *pino = ino; |
| 265 | return rc; |
| 266 | } |
| 267 | |
| 268 | static void sysfs_free_ino(ino_t ino) |
| 269 | { |
| 270 | spin_lock(&sysfs_ino_lock); |
| 271 | ida_remove(&sysfs_ino_ida, ino); |
| 272 | spin_unlock(&sysfs_ino_lock); |
| 273 | } |
| 274 | |
Tejun Heo | fa7f912 | 2007-06-14 03:45:13 +0900 | [diff] [blame] | 275 | void release_sysfs_dirent(struct sysfs_dirent * sd) |
| 276 | { |
Tejun Heo | 13b3086 | 2007-06-14 03:45:14 +0900 | [diff] [blame] | 277 | struct sysfs_dirent *parent_sd; |
| 278 | |
| 279 | repeat: |
Tejun Heo | 3007e99 | 2007-06-14 04:27:23 +0900 | [diff] [blame] | 280 | /* Moving/renaming is always done while holding reference. |
| 281 | * sd->s_parent won't change beneath us. |
| 282 | */ |
Tejun Heo | 13b3086 | 2007-06-14 03:45:14 +0900 | [diff] [blame] | 283 | parent_sd = sd->s_parent; |
| 284 | |
Tejun Heo | b402d72 | 2007-06-14 04:27:21 +0900 | [diff] [blame] | 285 | if (sysfs_type(sd) == SYSFS_KOBJ_LINK) |
Tejun Heo | b1fc3d6 | 2007-09-20 16:05:11 +0900 | [diff] [blame] | 286 | sysfs_put(sd->s_symlink.target_sd); |
Tejun Heo | b402d72 | 2007-06-14 04:27:21 +0900 | [diff] [blame] | 287 | if (sysfs_type(sd) & SYSFS_COPY_NAME) |
Tejun Heo | 0c096b5 | 2007-06-14 03:45:15 +0900 | [diff] [blame] | 288 | kfree(sd->s_name); |
Eric W. Biederman | 4c3da22 | 2009-11-04 02:50:06 -0800 | [diff] [blame] | 289 | if (sd->s_iattr && sd->s_iattr->ia_secdata) |
| 290 | security_release_secctx(sd->s_iattr->ia_secdata, |
| 291 | sd->s_iattr->ia_secdata_len); |
Tejun Heo | fa7f912 | 2007-06-14 03:45:13 +0900 | [diff] [blame] | 292 | kfree(sd->s_iattr); |
Tejun Heo | 2b611bb | 2007-06-14 03:45:13 +0900 | [diff] [blame] | 293 | sysfs_free_ino(sd->s_ino); |
Tejun Heo | fa7f912 | 2007-06-14 03:45:13 +0900 | [diff] [blame] | 294 | kmem_cache_free(sysfs_dir_cachep, sd); |
Tejun Heo | 13b3086 | 2007-06-14 03:45:14 +0900 | [diff] [blame] | 295 | |
| 296 | sd = parent_sd; |
| 297 | if (sd && atomic_dec_and_test(&sd->s_count)) |
| 298 | goto repeat; |
Tejun Heo | fa7f912 | 2007-06-14 03:45:13 +0900 | [diff] [blame] | 299 | } |
| 300 | |
Eric W. Biederman | e8f077c | 2009-11-07 23:27:01 -0800 | [diff] [blame^] | 301 | static int sysfs_dentry_delete(struct dentry *dentry) |
| 302 | { |
| 303 | struct sysfs_dirent *sd = dentry->d_fsdata; |
| 304 | return !!(sd->s_flags & SYSFS_FLAG_REMOVED); |
| 305 | } |
| 306 | |
| 307 | static int sysfs_dentry_revalidate(struct dentry *dentry, struct nameidata *nd) |
| 308 | { |
| 309 | struct sysfs_dirent *sd = dentry->d_fsdata; |
| 310 | int is_dir; |
| 311 | |
| 312 | mutex_lock(&sysfs_mutex); |
| 313 | |
| 314 | /* The sysfs dirent has been deleted */ |
| 315 | if (sd->s_flags & SYSFS_FLAG_REMOVED) |
| 316 | goto out_bad; |
| 317 | |
| 318 | mutex_unlock(&sysfs_mutex); |
| 319 | out_valid: |
| 320 | return 1; |
| 321 | out_bad: |
| 322 | /* Remove the dentry from the dcache hashes. |
| 323 | * If this is a deleted dentry we use d_drop instead of d_delete |
| 324 | * so sysfs doesn't need to cope with negative dentries. |
| 325 | */ |
| 326 | is_dir = (sysfs_type(sd) == SYSFS_DIR); |
| 327 | mutex_unlock(&sysfs_mutex); |
| 328 | if (is_dir) { |
| 329 | /* If we have submounts we must allow the vfs caches |
| 330 | * to lie about the state of the filesystem to prevent |
| 331 | * leaks and other nasty things. |
| 332 | */ |
| 333 | if (have_submounts(dentry)) |
| 334 | goto out_valid; |
| 335 | shrink_dcache_parent(dentry); |
| 336 | } |
| 337 | d_drop(dentry); |
| 338 | return 0; |
| 339 | } |
| 340 | |
Eric W. Biederman | 28a027c | 2009-11-07 23:27:00 -0800 | [diff] [blame] | 341 | static void sysfs_dentry_iput(struct dentry *dentry, struct inode *inode) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 342 | { |
| 343 | struct sysfs_dirent * sd = dentry->d_fsdata; |
| 344 | |
Eric W. Biederman | 5a26b79 | 2007-08-20 21:36:30 +0900 | [diff] [blame] | 345 | sysfs_put(sd); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 346 | iput(inode); |
| 347 | } |
| 348 | |
Al Viro | ee1ec32 | 2009-02-20 06:01:46 +0000 | [diff] [blame] | 349 | static const struct dentry_operations sysfs_dentry_ops = { |
Eric W. Biederman | e8f077c | 2009-11-07 23:27:01 -0800 | [diff] [blame^] | 350 | .d_revalidate = sysfs_dentry_revalidate, |
| 351 | .d_delete = sysfs_dentry_delete, |
Eric W. Biederman | 28a027c | 2009-11-07 23:27:00 -0800 | [diff] [blame] | 352 | .d_iput = sysfs_dentry_iput, |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 353 | }; |
| 354 | |
Tejun Heo | 3e51903 | 2007-06-14 03:45:15 +0900 | [diff] [blame] | 355 | 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] | 356 | { |
Tejun Heo | 0c096b5 | 2007-06-14 03:45:15 +0900 | [diff] [blame] | 357 | char *dup_name = NULL; |
Akinobu Mita | 01da242 | 2007-07-14 11:03:35 +0900 | [diff] [blame] | 358 | struct sysfs_dirent *sd; |
Tejun Heo | 0c096b5 | 2007-06-14 03:45:15 +0900 | [diff] [blame] | 359 | |
| 360 | if (type & SYSFS_COPY_NAME) { |
| 361 | name = dup_name = kstrdup(name, GFP_KERNEL); |
| 362 | if (!name) |
Akinobu Mita | 01da242 | 2007-07-14 11:03:35 +0900 | [diff] [blame] | 363 | return NULL; |
Tejun Heo | 0c096b5 | 2007-06-14 03:45:15 +0900 | [diff] [blame] | 364 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 365 | |
Robert P. J. Day | c376222 | 2007-02-10 01:45:03 -0800 | [diff] [blame] | 366 | sd = kmem_cache_zalloc(sysfs_dir_cachep, GFP_KERNEL); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 367 | if (!sd) |
Akinobu Mita | 01da242 | 2007-07-14 11:03:35 +0900 | [diff] [blame] | 368 | goto err_out1; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 369 | |
Tejun Heo | 0c096b5 | 2007-06-14 03:45:15 +0900 | [diff] [blame] | 370 | if (sysfs_alloc_ino(&sd->s_ino)) |
Akinobu Mita | 01da242 | 2007-07-14 11:03:35 +0900 | [diff] [blame] | 371 | goto err_out2; |
Tejun Heo | 2b611bb | 2007-06-14 03:45:13 +0900 | [diff] [blame] | 372 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 373 | atomic_set(&sd->s_count, 1); |
Tejun Heo | 8619f97 | 2007-06-14 03:45:18 +0900 | [diff] [blame] | 374 | atomic_set(&sd->s_active, 0); |
Tejun Heo | a26cd72 | 2007-06-14 03:45:14 +0900 | [diff] [blame] | 375 | |
Tejun Heo | 0c096b5 | 2007-06-14 03:45:15 +0900 | [diff] [blame] | 376 | sd->s_name = name; |
Tejun Heo | a26cd72 | 2007-06-14 03:45:14 +0900 | [diff] [blame] | 377 | sd->s_mode = mode; |
Tejun Heo | b402d72 | 2007-06-14 04:27:21 +0900 | [diff] [blame] | 378 | sd->s_flags = type; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 379 | |
| 380 | return sd; |
Tejun Heo | 0c096b5 | 2007-06-14 03:45:15 +0900 | [diff] [blame] | 381 | |
Akinobu Mita | 01da242 | 2007-07-14 11:03:35 +0900 | [diff] [blame] | 382 | err_out2: |
Tejun Heo | 0c096b5 | 2007-06-14 03:45:15 +0900 | [diff] [blame] | 383 | kmem_cache_free(sysfs_dir_cachep, sd); |
Akinobu Mita | 01da242 | 2007-07-14 11:03:35 +0900 | [diff] [blame] | 384 | err_out1: |
| 385 | kfree(dup_name); |
Tejun Heo | 0c096b5 | 2007-06-14 03:45:15 +0900 | [diff] [blame] | 386 | return NULL; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 387 | } |
| 388 | |
Tejun Heo | fb6896d | 2007-06-14 04:27:24 +0900 | [diff] [blame] | 389 | static int sysfs_ilookup_test(struct inode *inode, void *arg) |
| 390 | { |
| 391 | struct sysfs_dirent *sd = arg; |
| 392 | return inode->i_ino == sd->s_ino; |
| 393 | } |
| 394 | |
Tejun Heo | 3007e99 | 2007-06-14 04:27:23 +0900 | [diff] [blame] | 395 | /** |
Tejun Heo | fb6896d | 2007-06-14 04:27:24 +0900 | [diff] [blame] | 396 | * sysfs_addrm_start - prepare for sysfs_dirent add/remove |
| 397 | * @acxt: pointer to sysfs_addrm_cxt to be used |
| 398 | * @parent_sd: parent sysfs_dirent |
Tejun Heo | 3007e99 | 2007-06-14 04:27:23 +0900 | [diff] [blame] | 399 | * |
Tejun Heo | fb6896d | 2007-06-14 04:27:24 +0900 | [diff] [blame] | 400 | * This function is called when the caller is about to add or |
| 401 | * remove sysfs_dirent under @parent_sd. This function acquires |
| 402 | * sysfs_mutex, grabs inode for @parent_sd if available and lock |
| 403 | * i_mutex of it. @acxt is used to keep and pass context to |
| 404 | * other addrm functions. |
Tejun Heo | 3007e99 | 2007-06-14 04:27:23 +0900 | [diff] [blame] | 405 | * |
| 406 | * LOCKING: |
Tejun Heo | fb6896d | 2007-06-14 04:27:24 +0900 | [diff] [blame] | 407 | * Kernel thread context (may sleep). sysfs_mutex is locked on |
| 408 | * return. i_mutex of parent inode is locked on return if |
| 409 | * available. |
Tejun Heo | 3007e99 | 2007-06-14 04:27:23 +0900 | [diff] [blame] | 410 | */ |
Tejun Heo | fb6896d | 2007-06-14 04:27:24 +0900 | [diff] [blame] | 411 | void sysfs_addrm_start(struct sysfs_addrm_cxt *acxt, |
| 412 | struct sysfs_dirent *parent_sd) |
Eric W. Biederman | b592fcf | 2007-01-24 12:35:52 -0700 | [diff] [blame] | 413 | { |
Tejun Heo | fb6896d | 2007-06-14 04:27:24 +0900 | [diff] [blame] | 414 | struct inode *inode; |
Tejun Heo | a26cd72 | 2007-06-14 03:45:14 +0900 | [diff] [blame] | 415 | |
Tejun Heo | fb6896d | 2007-06-14 04:27:24 +0900 | [diff] [blame] | 416 | memset(acxt, 0, sizeof(*acxt)); |
| 417 | acxt->parent_sd = parent_sd; |
| 418 | |
Tejun Heo | 45c076c | 2008-09-28 07:48:08 +0900 | [diff] [blame] | 419 | /* Lookup parent inode. inode initialization is protected by |
| 420 | * sysfs_mutex, so inode existence can be determined by |
| 421 | * looking up inode while holding sysfs_mutex. |
Tejun Heo | fb6896d | 2007-06-14 04:27:24 +0900 | [diff] [blame] | 422 | */ |
| 423 | mutex_lock(&sysfs_mutex); |
| 424 | |
Tejun Heo | 45c076c | 2008-09-28 07:48:08 +0900 | [diff] [blame] | 425 | inode = ilookup5(sysfs_sb, parent_sd->s_ino, sysfs_ilookup_test, |
| 426 | parent_sd); |
| 427 | if (inode) { |
| 428 | WARN_ON(inode->i_state & I_NEW); |
Tejun Heo | fb6896d | 2007-06-14 04:27:24 +0900 | [diff] [blame] | 429 | |
Tejun Heo | fb6896d | 2007-06-14 04:27:24 +0900 | [diff] [blame] | 430 | /* parent inode available */ |
| 431 | acxt->parent_inode = inode; |
| 432 | |
| 433 | /* sysfs_mutex is below i_mutex in lock hierarchy. |
| 434 | * First, trylock i_mutex. If fails, unlock |
| 435 | * sysfs_mutex and lock them in order. |
| 436 | */ |
| 437 | if (!mutex_trylock(&inode->i_mutex)) { |
| 438 | mutex_unlock(&sysfs_mutex); |
| 439 | mutex_lock(&inode->i_mutex); |
| 440 | mutex_lock(&sysfs_mutex); |
| 441 | } |
Tejun Heo | 45c076c | 2008-09-28 07:48:08 +0900 | [diff] [blame] | 442 | } |
Tejun Heo | fb6896d | 2007-06-14 04:27:24 +0900 | [diff] [blame] | 443 | } |
| 444 | |
| 445 | /** |
Cornelia Huck | 36ce6da | 2008-06-10 11:09:08 +0200 | [diff] [blame] | 446 | * __sysfs_add_one - add sysfs_dirent to parent without warning |
| 447 | * @acxt: addrm context to use |
| 448 | * @sd: sysfs_dirent to be added |
| 449 | * |
| 450 | * Get @acxt->parent_sd and set sd->s_parent to it and increment |
| 451 | * nlink of parent inode if @sd is a directory and link into the |
| 452 | * children list of the parent. |
| 453 | * |
| 454 | * This function should be called between calls to |
| 455 | * sysfs_addrm_start() and sysfs_addrm_finish() and should be |
| 456 | * passed the same @acxt as passed to sysfs_addrm_start(). |
| 457 | * |
| 458 | * LOCKING: |
| 459 | * Determined by sysfs_addrm_start(). |
| 460 | * |
| 461 | * RETURNS: |
| 462 | * 0 on success, -EEXIST if entry with the given name already |
| 463 | * exists. |
| 464 | */ |
| 465 | int __sysfs_add_one(struct sysfs_addrm_cxt *acxt, struct sysfs_dirent *sd) |
| 466 | { |
| 467 | if (sysfs_find_dirent(acxt->parent_sd, sd->s_name)) |
| 468 | return -EEXIST; |
| 469 | |
| 470 | sd->s_parent = sysfs_get(acxt->parent_sd); |
| 471 | |
| 472 | if (sysfs_type(sd) == SYSFS_DIR && acxt->parent_inode) |
| 473 | inc_nlink(acxt->parent_inode); |
| 474 | |
| 475 | acxt->cnt++; |
| 476 | |
| 477 | sysfs_link_sibling(sd); |
| 478 | |
| 479 | return 0; |
| 480 | } |
| 481 | |
| 482 | /** |
Alex Chiang | 425cb02 | 2009-02-12 10:56:59 -0700 | [diff] [blame] | 483 | * sysfs_pathname - return full path to sysfs dirent |
| 484 | * @sd: sysfs_dirent whose path we want |
| 485 | * @path: caller allocated buffer |
| 486 | * |
| 487 | * Gives the name "/" to the sysfs_root entry; any path returned |
| 488 | * is relative to wherever sysfs is mounted. |
| 489 | * |
| 490 | * XXX: does no error checking on @path size |
| 491 | */ |
| 492 | static char *sysfs_pathname(struct sysfs_dirent *sd, char *path) |
| 493 | { |
| 494 | if (sd->s_parent) { |
| 495 | sysfs_pathname(sd->s_parent, path); |
| 496 | strcat(path, "/"); |
| 497 | } |
| 498 | strcat(path, sd->s_name); |
| 499 | return path; |
| 500 | } |
| 501 | |
| 502 | /** |
Tejun Heo | fb6896d | 2007-06-14 04:27:24 +0900 | [diff] [blame] | 503 | * sysfs_add_one - add sysfs_dirent to parent |
| 504 | * @acxt: addrm context to use |
| 505 | * @sd: sysfs_dirent to be added |
| 506 | * |
| 507 | * 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] | 508 | * nlink of parent inode if @sd is a directory and link into the |
| 509 | * children list of the parent. |
Tejun Heo | fb6896d | 2007-06-14 04:27:24 +0900 | [diff] [blame] | 510 | * |
| 511 | * This function should be called between calls to |
| 512 | * sysfs_addrm_start() and sysfs_addrm_finish() and should be |
| 513 | * passed the same @acxt as passed to sysfs_addrm_start(). |
| 514 | * |
| 515 | * LOCKING: |
| 516 | * Determined by sysfs_addrm_start(). |
Tejun Heo | 23dc279 | 2007-08-02 21:38:03 +0900 | [diff] [blame] | 517 | * |
| 518 | * RETURNS: |
| 519 | * 0 on success, -EEXIST if entry with the given name already |
| 520 | * exists. |
Tejun Heo | fb6896d | 2007-06-14 04:27:24 +0900 | [diff] [blame] | 521 | */ |
Tejun Heo | 23dc279 | 2007-08-02 21:38:03 +0900 | [diff] [blame] | 522 | 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] | 523 | { |
Cornelia Huck | 36ce6da | 2008-06-10 11:09:08 +0200 | [diff] [blame] | 524 | int ret; |
Tejun Heo | 23dc279 | 2007-08-02 21:38:03 +0900 | [diff] [blame] | 525 | |
Cornelia Huck | 36ce6da | 2008-06-10 11:09:08 +0200 | [diff] [blame] | 526 | ret = __sysfs_add_one(acxt, sd); |
Alex Chiang | 425cb02 | 2009-02-12 10:56:59 -0700 | [diff] [blame] | 527 | if (ret == -EEXIST) { |
| 528 | char *path = kzalloc(PATH_MAX, GFP_KERNEL); |
| 529 | WARN(1, KERN_WARNING |
| 530 | "sysfs: cannot create duplicate filename '%s'\n", |
| 531 | (path == NULL) ? sd->s_name : |
| 532 | strcat(strcat(sysfs_pathname(acxt->parent_sd, path), "/"), |
| 533 | sd->s_name)); |
| 534 | kfree(path); |
| 535 | } |
| 536 | |
Cornelia Huck | 36ce6da | 2008-06-10 11:09:08 +0200 | [diff] [blame] | 537 | return ret; |
Tejun Heo | fb6896d | 2007-06-14 04:27:24 +0900 | [diff] [blame] | 538 | } |
| 539 | |
| 540 | /** |
| 541 | * sysfs_remove_one - remove sysfs_dirent from parent |
| 542 | * @acxt: addrm context to use |
Jean Delvare | 9fd5b1c | 2008-01-08 18:11:24 +0100 | [diff] [blame] | 543 | * @sd: sysfs_dirent to be removed |
Tejun Heo | fb6896d | 2007-06-14 04:27:24 +0900 | [diff] [blame] | 544 | * |
| 545 | * 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] | 546 | * directory. @sd is unlinked from the children list. |
Tejun Heo | fb6896d | 2007-06-14 04:27:24 +0900 | [diff] [blame] | 547 | * |
| 548 | * This function should be called between calls to |
| 549 | * sysfs_addrm_start() and sysfs_addrm_finish() and should be |
| 550 | * passed the same @acxt as passed to sysfs_addrm_start(). |
| 551 | * |
| 552 | * LOCKING: |
| 553 | * Determined by sysfs_addrm_start(). |
| 554 | */ |
| 555 | void sysfs_remove_one(struct sysfs_addrm_cxt *acxt, struct sysfs_dirent *sd) |
| 556 | { |
Tejun Heo | 41fc1c2 | 2007-08-02 21:38:03 +0900 | [diff] [blame] | 557 | BUG_ON(sd->s_flags & SYSFS_FLAG_REMOVED); |
| 558 | |
| 559 | sysfs_unlink_sibling(sd); |
Tejun Heo | fb6896d | 2007-06-14 04:27:24 +0900 | [diff] [blame] | 560 | |
| 561 | sd->s_flags |= SYSFS_FLAG_REMOVED; |
| 562 | sd->s_sibling = acxt->removed; |
| 563 | acxt->removed = sd; |
| 564 | |
| 565 | if (sysfs_type(sd) == SYSFS_DIR && acxt->parent_inode) |
| 566 | drop_nlink(acxt->parent_inode); |
| 567 | |
| 568 | acxt->cnt++; |
| 569 | } |
| 570 | |
| 571 | /** |
Eric W. Biederman | e8f077c | 2009-11-07 23:27:01 -0800 | [diff] [blame^] | 572 | * sysfs_dec_nlink - Decrement link count for the specified sysfs_dirent |
Tejun Heo | a0edd7c | 2007-06-14 04:27:24 +0900 | [diff] [blame] | 573 | * @sd: target sysfs_dirent |
| 574 | * |
Eric W. Biederman | e8f077c | 2009-11-07 23:27:01 -0800 | [diff] [blame^] | 575 | * Decrement nlink for @sd. @sd must have been unlinked from its |
Tejun Heo | a0edd7c | 2007-06-14 04:27:24 +0900 | [diff] [blame] | 576 | * parent on entry to this function such that it can't be looked |
| 577 | * up anymore. |
Tejun Heo | a0edd7c | 2007-06-14 04:27:24 +0900 | [diff] [blame] | 578 | */ |
Eric W. Biederman | e8f077c | 2009-11-07 23:27:01 -0800 | [diff] [blame^] | 579 | static void sysfs_dec_nlink(struct sysfs_dirent *sd) |
Tejun Heo | a0edd7c | 2007-06-14 04:27:24 +0900 | [diff] [blame] | 580 | { |
Tejun Heo | a0edd7c | 2007-06-14 04:27:24 +0900 | [diff] [blame] | 581 | struct inode *inode; |
| 582 | |
Eric W. Biederman | 89bec09 | 2007-08-20 21:36:30 +0900 | [diff] [blame] | 583 | inode = ilookup(sysfs_sb, sd->s_ino); |
| 584 | if (!inode) |
| 585 | return; |
| 586 | |
Tejun Heo | a0edd7c | 2007-06-14 04:27:24 +0900 | [diff] [blame] | 587 | /* adjust nlink and update timestamp */ |
Eric W. Biederman | 89bec09 | 2007-08-20 21:36:30 +0900 | [diff] [blame] | 588 | mutex_lock(&inode->i_mutex); |
Tejun Heo | a0edd7c | 2007-06-14 04:27:24 +0900 | [diff] [blame] | 589 | |
Eric W. Biederman | 89bec09 | 2007-08-20 21:36:30 +0900 | [diff] [blame] | 590 | inode->i_ctime = CURRENT_TIME; |
| 591 | drop_nlink(inode); |
| 592 | if (sysfs_type(sd) == SYSFS_DIR) |
Tejun Heo | a0edd7c | 2007-06-14 04:27:24 +0900 | [diff] [blame] | 593 | drop_nlink(inode); |
Tejun Heo | a0edd7c | 2007-06-14 04:27:24 +0900 | [diff] [blame] | 594 | |
Eric W. Biederman | 89bec09 | 2007-08-20 21:36:30 +0900 | [diff] [blame] | 595 | mutex_unlock(&inode->i_mutex); |
| 596 | |
| 597 | iput(inode); |
Tejun Heo | a0edd7c | 2007-06-14 04:27:24 +0900 | [diff] [blame] | 598 | } |
| 599 | |
| 600 | /** |
Tejun Heo | fb6896d | 2007-06-14 04:27:24 +0900 | [diff] [blame] | 601 | * sysfs_addrm_finish - finish up sysfs_dirent add/remove |
| 602 | * @acxt: addrm context to finish up |
| 603 | * |
| 604 | * Finish up sysfs_dirent add/remove. Resources acquired by |
| 605 | * sysfs_addrm_start() are released and removed sysfs_dirents are |
| 606 | * cleaned up. Timestamps on the parent inode are updated. |
| 607 | * |
| 608 | * LOCKING: |
| 609 | * All mutexes acquired by sysfs_addrm_start() are released. |
Tejun Heo | fb6896d | 2007-06-14 04:27:24 +0900 | [diff] [blame] | 610 | */ |
Tejun Heo | 990e53f | 2007-08-02 21:38:03 +0900 | [diff] [blame] | 611 | void sysfs_addrm_finish(struct sysfs_addrm_cxt *acxt) |
Tejun Heo | fb6896d | 2007-06-14 04:27:24 +0900 | [diff] [blame] | 612 | { |
| 613 | /* release resources acquired by sysfs_addrm_start() */ |
| 614 | mutex_unlock(&sysfs_mutex); |
| 615 | if (acxt->parent_inode) { |
| 616 | struct inode *inode = acxt->parent_inode; |
| 617 | |
| 618 | /* if added/removed, update timestamps on the parent */ |
| 619 | if (acxt->cnt) |
| 620 | inode->i_ctime = inode->i_mtime = CURRENT_TIME; |
| 621 | |
| 622 | mutex_unlock(&inode->i_mutex); |
| 623 | iput(inode); |
Tejun Heo | 13b3086 | 2007-06-14 03:45:14 +0900 | [diff] [blame] | 624 | } |
Tejun Heo | fb6896d | 2007-06-14 04:27:24 +0900 | [diff] [blame] | 625 | |
| 626 | /* kill removed sysfs_dirents */ |
| 627 | while (acxt->removed) { |
| 628 | struct sysfs_dirent *sd = acxt->removed; |
| 629 | |
| 630 | acxt->removed = sd->s_sibling; |
| 631 | sd->s_sibling = NULL; |
| 632 | |
Eric W. Biederman | e8f077c | 2009-11-07 23:27:01 -0800 | [diff] [blame^] | 633 | sysfs_dec_nlink(sd); |
Tejun Heo | fb6896d | 2007-06-14 04:27:24 +0900 | [diff] [blame] | 634 | sysfs_deactivate(sd); |
Eric W. Biederman | e0edd3c | 2009-03-04 11:57:20 -0800 | [diff] [blame] | 635 | unmap_bin_file(sd); |
Tejun Heo | fb6896d | 2007-06-14 04:27:24 +0900 | [diff] [blame] | 636 | sysfs_put(sd); |
| 637 | } |
Eric W. Biederman | b592fcf | 2007-01-24 12:35:52 -0700 | [diff] [blame] | 638 | } |
| 639 | |
Tejun Heo | f0b0af4 | 2007-06-14 04:27:22 +0900 | [diff] [blame] | 640 | /** |
| 641 | * sysfs_find_dirent - find sysfs_dirent with the given name |
| 642 | * @parent_sd: sysfs_dirent to search under |
| 643 | * @name: name to look for |
Maneesh Soni | c516865 | 2006-03-09 19:40:14 +0530 | [diff] [blame] | 644 | * |
Tejun Heo | f0b0af4 | 2007-06-14 04:27:22 +0900 | [diff] [blame] | 645 | * Look for sysfs_dirent with name @name under @parent_sd. |
Maneesh Soni | c516865 | 2006-03-09 19:40:14 +0530 | [diff] [blame] | 646 | * |
Tejun Heo | f0b0af4 | 2007-06-14 04:27:22 +0900 | [diff] [blame] | 647 | * LOCKING: |
Tejun Heo | 3007e99 | 2007-06-14 04:27:23 +0900 | [diff] [blame] | 648 | * mutex_lock(sysfs_mutex) |
Tejun Heo | f0b0af4 | 2007-06-14 04:27:22 +0900 | [diff] [blame] | 649 | * |
| 650 | * RETURNS: |
| 651 | * Pointer to sysfs_dirent if found, NULL if not. |
Maneesh Soni | c516865 | 2006-03-09 19:40:14 +0530 | [diff] [blame] | 652 | */ |
Tejun Heo | f0b0af4 | 2007-06-14 04:27:22 +0900 | [diff] [blame] | 653 | struct sysfs_dirent *sysfs_find_dirent(struct sysfs_dirent *parent_sd, |
| 654 | const unsigned char *name) |
Maneesh Soni | c516865 | 2006-03-09 19:40:14 +0530 | [diff] [blame] | 655 | { |
Tejun Heo | f0b0af4 | 2007-06-14 04:27:22 +0900 | [diff] [blame] | 656 | struct sysfs_dirent *sd; |
Maneesh Soni | c516865 | 2006-03-09 19:40:14 +0530 | [diff] [blame] | 657 | |
Tejun Heo | bc747f3 | 2007-09-20 16:05:12 +0900 | [diff] [blame] | 658 | 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] | 659 | if (!strcmp(sd->s_name, name)) |
Tejun Heo | f0b0af4 | 2007-06-14 04:27:22 +0900 | [diff] [blame] | 660 | return sd; |
| 661 | return NULL; |
| 662 | } |
Maneesh Soni | c516865 | 2006-03-09 19:40:14 +0530 | [diff] [blame] | 663 | |
Tejun Heo | f0b0af4 | 2007-06-14 04:27:22 +0900 | [diff] [blame] | 664 | /** |
| 665 | * sysfs_get_dirent - find and get sysfs_dirent with the given name |
| 666 | * @parent_sd: sysfs_dirent to search under |
| 667 | * @name: name to look for |
| 668 | * |
| 669 | * Look for sysfs_dirent with name @name under @parent_sd and get |
| 670 | * it if found. |
| 671 | * |
| 672 | * LOCKING: |
Tejun Heo | 3007e99 | 2007-06-14 04:27:23 +0900 | [diff] [blame] | 673 | * Kernel thread context (may sleep). Grabs sysfs_mutex. |
Tejun Heo | f0b0af4 | 2007-06-14 04:27:22 +0900 | [diff] [blame] | 674 | * |
| 675 | * RETURNS: |
| 676 | * Pointer to sysfs_dirent if found, NULL if not. |
| 677 | */ |
| 678 | struct sysfs_dirent *sysfs_get_dirent(struct sysfs_dirent *parent_sd, |
| 679 | const unsigned char *name) |
| 680 | { |
| 681 | struct sysfs_dirent *sd; |
| 682 | |
Tejun Heo | 3007e99 | 2007-06-14 04:27:23 +0900 | [diff] [blame] | 683 | mutex_lock(&sysfs_mutex); |
Tejun Heo | f0b0af4 | 2007-06-14 04:27:22 +0900 | [diff] [blame] | 684 | sd = sysfs_find_dirent(parent_sd, name); |
| 685 | sysfs_get(sd); |
Tejun Heo | 3007e99 | 2007-06-14 04:27:23 +0900 | [diff] [blame] | 686 | mutex_unlock(&sysfs_mutex); |
Tejun Heo | f0b0af4 | 2007-06-14 04:27:22 +0900 | [diff] [blame] | 687 | |
| 688 | return sd; |
Maneesh Soni | c516865 | 2006-03-09 19:40:14 +0530 | [diff] [blame] | 689 | } |
Neil Brown | f1282c8 | 2008-07-16 08:58:04 +1000 | [diff] [blame] | 690 | EXPORT_SYMBOL_GPL(sysfs_get_dirent); |
Maneesh Soni | c516865 | 2006-03-09 19:40:14 +0530 | [diff] [blame] | 691 | |
Tejun Heo | 608e266 | 2007-06-14 04:27:22 +0900 | [diff] [blame] | 692 | static int create_dir(struct kobject *kobj, struct sysfs_dirent *parent_sd, |
| 693 | const char *name, struct sysfs_dirent **p_sd) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 694 | { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 695 | umode_t mode = S_IFDIR| S_IRWXU | S_IRUGO | S_IXUGO; |
Tejun Heo | 5122503 | 2007-06-14 04:27:25 +0900 | [diff] [blame] | 696 | struct sysfs_addrm_cxt acxt; |
Tejun Heo | dfeb9fb | 2007-06-14 03:45:14 +0900 | [diff] [blame] | 697 | struct sysfs_dirent *sd; |
Tejun Heo | 23dc279 | 2007-08-02 21:38:03 +0900 | [diff] [blame] | 698 | int rc; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 699 | |
Tejun Heo | fc9f54b | 2007-06-14 03:45:17 +0900 | [diff] [blame] | 700 | /* allocate */ |
Tejun Heo | 3e51903 | 2007-06-14 03:45:15 +0900 | [diff] [blame] | 701 | sd = sysfs_new_dirent(name, mode, SYSFS_DIR); |
Tejun Heo | a26cd72 | 2007-06-14 03:45:14 +0900 | [diff] [blame] | 702 | if (!sd) |
Tejun Heo | 5122503 | 2007-06-14 04:27:25 +0900 | [diff] [blame] | 703 | return -ENOMEM; |
Tejun Heo | b1fc3d6 | 2007-09-20 16:05:11 +0900 | [diff] [blame] | 704 | sd->s_dir.kobj = kobj; |
Tejun Heo | dfeb9fb | 2007-06-14 03:45:14 +0900 | [diff] [blame] | 705 | |
Tejun Heo | 5122503 | 2007-06-14 04:27:25 +0900 | [diff] [blame] | 706 | /* link in */ |
| 707 | sysfs_addrm_start(&acxt, parent_sd); |
Tejun Heo | 23dc279 | 2007-08-02 21:38:03 +0900 | [diff] [blame] | 708 | rc = sysfs_add_one(&acxt, sd); |
| 709 | sysfs_addrm_finish(&acxt); |
Tejun Heo | 967e35d | 2007-07-18 16:38:11 +0900 | [diff] [blame] | 710 | |
Tejun Heo | 23dc279 | 2007-08-02 21:38:03 +0900 | [diff] [blame] | 711 | if (rc == 0) |
| 712 | *p_sd = sd; |
| 713 | else |
Tejun Heo | 967e35d | 2007-07-18 16:38:11 +0900 | [diff] [blame] | 714 | sysfs_put(sd); |
Tejun Heo | fc9f54b | 2007-06-14 03:45:17 +0900 | [diff] [blame] | 715 | |
Tejun Heo | 23dc279 | 2007-08-02 21:38:03 +0900 | [diff] [blame] | 716 | return rc; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 717 | } |
| 718 | |
Tejun Heo | 608e266 | 2007-06-14 04:27:22 +0900 | [diff] [blame] | 719 | int sysfs_create_subdir(struct kobject *kobj, const char *name, |
| 720 | struct sysfs_dirent **p_sd) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 721 | { |
Tejun Heo | 608e266 | 2007-06-14 04:27:22 +0900 | [diff] [blame] | 722 | return create_dir(kobj, kobj->sd, name, p_sd); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 723 | } |
| 724 | |
| 725 | /** |
| 726 | * sysfs_create_dir - create a directory for an object. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 727 | * @kobj: object we're creating directory for. |
| 728 | */ |
Eric W. Biederman | 90bc613 | 2007-07-31 19:15:08 +0900 | [diff] [blame] | 729 | int sysfs_create_dir(struct kobject * kobj) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 730 | { |
Tejun Heo | 608e266 | 2007-06-14 04:27:22 +0900 | [diff] [blame] | 731 | struct sysfs_dirent *parent_sd, *sd; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 732 | int error = 0; |
| 733 | |
| 734 | BUG_ON(!kobj); |
| 735 | |
Eric W. Biederman | 90bc613 | 2007-07-31 19:15:08 +0900 | [diff] [blame] | 736 | if (kobj->parent) |
Tejun Heo | 608e266 | 2007-06-14 04:27:22 +0900 | [diff] [blame] | 737 | parent_sd = kobj->parent->sd; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 738 | else |
Eric W. Biederman | 7d0c7d6 | 2007-08-20 21:36:30 +0900 | [diff] [blame] | 739 | parent_sd = &sysfs_root; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 740 | |
Tejun Heo | 608e266 | 2007-06-14 04:27:22 +0900 | [diff] [blame] | 741 | error = create_dir(kobj, parent_sd, kobject_name(kobj), &sd); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 742 | if (!error) |
Tejun Heo | 608e266 | 2007-06-14 04:27:22 +0900 | [diff] [blame] | 743 | kobj->sd = sd; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 744 | return error; |
| 745 | } |
| 746 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 747 | static struct dentry * sysfs_lookup(struct inode *dir, struct dentry *dentry, |
| 748 | struct nameidata *nd) |
| 749 | { |
Tejun Heo | 6cb5214 | 2007-07-31 19:15:08 +0900 | [diff] [blame] | 750 | struct dentry *ret = NULL; |
Tejun Heo | a7a0475 | 2007-08-02 21:38:02 +0900 | [diff] [blame] | 751 | struct sysfs_dirent *parent_sd = dentry->d_parent->d_fsdata; |
| 752 | struct sysfs_dirent *sd; |
Tejun Heo | fc9f54b | 2007-06-14 03:45:17 +0900 | [diff] [blame] | 753 | struct inode *inode; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 754 | |
Tejun Heo | 6cb5214 | 2007-07-31 19:15:08 +0900 | [diff] [blame] | 755 | mutex_lock(&sysfs_mutex); |
| 756 | |
Eric W. Biederman | 94777e0 | 2007-08-20 21:36:30 +0900 | [diff] [blame] | 757 | sd = sysfs_find_dirent(parent_sd, dentry->d_name.name); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 758 | |
Tejun Heo | fc9f54b | 2007-06-14 03:45:17 +0900 | [diff] [blame] | 759 | /* no such entry */ |
Tejun Heo | e49452c | 2008-01-16 12:06:14 +0900 | [diff] [blame] | 760 | if (!sd) { |
| 761 | ret = ERR_PTR(-ENOENT); |
Tejun Heo | 6cb5214 | 2007-07-31 19:15:08 +0900 | [diff] [blame] | 762 | goto out_unlock; |
Tejun Heo | e49452c | 2008-01-16 12:06:14 +0900 | [diff] [blame] | 763 | } |
Tejun Heo | fc9f54b | 2007-06-14 03:45:17 +0900 | [diff] [blame] | 764 | |
| 765 | /* attach dentry and inode */ |
Tejun Heo | 8312a8d | 2007-06-14 03:45:17 +0900 | [diff] [blame] | 766 | inode = sysfs_get_inode(sd); |
Tejun Heo | 6cb5214 | 2007-07-31 19:15:08 +0900 | [diff] [blame] | 767 | if (!inode) { |
| 768 | ret = ERR_PTR(-ENOMEM); |
| 769 | goto out_unlock; |
| 770 | } |
Tejun Heo | 3007e99 | 2007-06-14 04:27:23 +0900 | [diff] [blame] | 771 | |
Tejun Heo | d6b4fd2 | 2007-09-20 16:05:11 +0900 | [diff] [blame] | 772 | /* instantiate and hash dentry */ |
| 773 | dentry->d_op = &sysfs_dentry_ops; |
| 774 | dentry->d_fsdata = sysfs_get(sd); |
Eric W. Biederman | 119dd52 | 2007-08-20 21:36:29 +0900 | [diff] [blame] | 775 | d_instantiate(dentry, inode); |
Tejun Heo | d6b4fd2 | 2007-09-20 16:05:11 +0900 | [diff] [blame] | 776 | d_rehash(dentry); |
Tejun Heo | fc9f54b | 2007-06-14 03:45:17 +0900 | [diff] [blame] | 777 | |
Tejun Heo | 6cb5214 | 2007-07-31 19:15:08 +0900 | [diff] [blame] | 778 | out_unlock: |
Tejun Heo | 3007e99 | 2007-06-14 04:27:23 +0900 | [diff] [blame] | 779 | mutex_unlock(&sysfs_mutex); |
Tejun Heo | 6cb5214 | 2007-07-31 19:15:08 +0900 | [diff] [blame] | 780 | return ret; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 781 | } |
| 782 | |
Arjan van de Ven | c5ef1c4 | 2007-02-12 00:55:40 -0800 | [diff] [blame] | 783 | const struct inode_operations sysfs_dir_inode_operations = { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 784 | .lookup = sysfs_lookup, |
Maneesh Soni | 988d186 | 2005-05-31 10:39:14 +0530 | [diff] [blame] | 785 | .setattr = sysfs_setattr, |
David P. Quigley | ddd29ec | 2009-09-09 14:25:37 -0400 | [diff] [blame] | 786 | .setxattr = sysfs_setxattr, |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 787 | }; |
| 788 | |
Tejun Heo | 608e266 | 2007-06-14 04:27:22 +0900 | [diff] [blame] | 789 | static void remove_dir(struct sysfs_dirent *sd) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 790 | { |
Tejun Heo | fb6896d | 2007-06-14 04:27:24 +0900 | [diff] [blame] | 791 | struct sysfs_addrm_cxt acxt; |
| 792 | |
| 793 | sysfs_addrm_start(&acxt, sd->s_parent); |
Tejun Heo | fb6896d | 2007-06-14 04:27:24 +0900 | [diff] [blame] | 794 | sysfs_remove_one(&acxt, sd); |
| 795 | sysfs_addrm_finish(&acxt); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 796 | } |
| 797 | |
Tejun Heo | 608e266 | 2007-06-14 04:27:22 +0900 | [diff] [blame] | 798 | void sysfs_remove_subdir(struct sysfs_dirent *sd) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 799 | { |
Tejun Heo | 608e266 | 2007-06-14 04:27:22 +0900 | [diff] [blame] | 800 | remove_dir(sd); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 801 | } |
| 802 | |
| 803 | |
Tejun Heo | 608e266 | 2007-06-14 04:27:22 +0900 | [diff] [blame] | 804 | static void __sysfs_remove_dir(struct sysfs_dirent *dir_sd) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 805 | { |
Tejun Heo | fb6896d | 2007-06-14 04:27:24 +0900 | [diff] [blame] | 806 | struct sysfs_addrm_cxt acxt; |
Tejun Heo | 0c73f18 | 2007-06-14 03:45:18 +0900 | [diff] [blame] | 807 | struct sysfs_dirent **pos; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 808 | |
Tejun Heo | 608e266 | 2007-06-14 04:27:22 +0900 | [diff] [blame] | 809 | if (!dir_sd) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 810 | return; |
| 811 | |
Tejun Heo | 608e266 | 2007-06-14 04:27:22 +0900 | [diff] [blame] | 812 | pr_debug("sysfs %s: removing dir\n", dir_sd->s_name); |
Tejun Heo | fb6896d | 2007-06-14 04:27:24 +0900 | [diff] [blame] | 813 | sysfs_addrm_start(&acxt, dir_sd); |
Tejun Heo | bc747f3 | 2007-09-20 16:05:12 +0900 | [diff] [blame] | 814 | pos = &dir_sd->s_dir.children; |
Tejun Heo | 0c73f18 | 2007-06-14 03:45:18 +0900 | [diff] [blame] | 815 | while (*pos) { |
| 816 | struct sysfs_dirent *sd = *pos; |
| 817 | |
Eric W. Biederman | 3efa65b | 2007-08-20 21:36:30 +0900 | [diff] [blame] | 818 | if (sysfs_type(sd) != SYSFS_DIR) |
Tejun Heo | fb6896d | 2007-06-14 04:27:24 +0900 | [diff] [blame] | 819 | sysfs_remove_one(&acxt, sd); |
Tejun Heo | 41fc1c2 | 2007-08-02 21:38:03 +0900 | [diff] [blame] | 820 | else |
Tejun Heo | 0c73f18 | 2007-06-14 03:45:18 +0900 | [diff] [blame] | 821 | pos = &(*pos)->s_sibling; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 822 | } |
Tejun Heo | fb6896d | 2007-06-14 04:27:24 +0900 | [diff] [blame] | 823 | sysfs_addrm_finish(&acxt); |
Tejun Heo | 0ab6608 | 2007-06-14 03:45:16 +0900 | [diff] [blame] | 824 | |
Tejun Heo | 608e266 | 2007-06-14 04:27:22 +0900 | [diff] [blame] | 825 | remove_dir(dir_sd); |
Eric W. Biederman | b592fcf | 2007-01-24 12:35:52 -0700 | [diff] [blame] | 826 | } |
| 827 | |
| 828 | /** |
| 829 | * sysfs_remove_dir - remove an object's directory. |
| 830 | * @kobj: object. |
| 831 | * |
| 832 | * The only thing special about this is that we remove any files in |
| 833 | * the directory before we remove the directory, and we've inlined |
| 834 | * what used to be sysfs_rmdir() below, instead of calling separately. |
| 835 | */ |
| 836 | |
| 837 | void sysfs_remove_dir(struct kobject * kobj) |
| 838 | { |
Tejun Heo | 608e266 | 2007-06-14 04:27:22 +0900 | [diff] [blame] | 839 | struct sysfs_dirent *sd = kobj->sd; |
Tejun Heo | aecdced | 2007-06-14 03:45:15 +0900 | [diff] [blame] | 840 | |
Tejun Heo | 5f99532 | 2007-06-14 04:27:23 +0900 | [diff] [blame] | 841 | spin_lock(&sysfs_assoc_lock); |
Tejun Heo | 608e266 | 2007-06-14 04:27:22 +0900 | [diff] [blame] | 842 | kobj->sd = NULL; |
Tejun Heo | 5f99532 | 2007-06-14 04:27:23 +0900 | [diff] [blame] | 843 | spin_unlock(&sysfs_assoc_lock); |
Tejun Heo | aecdced | 2007-06-14 03:45:15 +0900 | [diff] [blame] | 844 | |
Tejun Heo | 608e266 | 2007-06-14 04:27:22 +0900 | [diff] [blame] | 845 | __sysfs_remove_dir(sd); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 846 | } |
| 847 | |
Eric W. Biederman | 90bc613 | 2007-07-31 19:15:08 +0900 | [diff] [blame] | 848 | int sysfs_rename_dir(struct kobject * kobj, const char *new_name) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 849 | { |
Eric W. Biederman | 9918f9a | 2007-08-20 21:36:31 +0900 | [diff] [blame] | 850 | struct sysfs_dirent *sd = kobj->sd; |
Eric W. Biederman | 90bc613 | 2007-07-31 19:15:08 +0900 | [diff] [blame] | 851 | struct dentry *parent = NULL; |
Tejun Heo | 5122503 | 2007-06-14 04:27:25 +0900 | [diff] [blame] | 852 | struct dentry *old_dentry = NULL, *new_dentry = NULL; |
| 853 | const char *dup_name = NULL; |
Tejun Heo | 996b737 | 2007-06-14 03:45:14 +0900 | [diff] [blame] | 854 | int error; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 855 | |
Eric W. Biederman | 932ea2e | 2007-08-20 21:36:30 +0900 | [diff] [blame] | 856 | mutex_lock(&sysfs_rename_mutex); |
| 857 | |
Eric W. Biederman | 9918f9a | 2007-08-20 21:36:31 +0900 | [diff] [blame] | 858 | error = 0; |
| 859 | if (strcmp(sd->s_name, new_name) == 0) |
| 860 | goto out; /* nothing to rename */ |
| 861 | |
Tejun Heo | ff869de | 2007-08-02 21:38:02 +0900 | [diff] [blame] | 862 | /* get the original dentry */ |
Tejun Heo | 5122503 | 2007-06-14 04:27:25 +0900 | [diff] [blame] | 863 | old_dentry = sysfs_get_dentry(sd); |
| 864 | if (IS_ERR(old_dentry)) { |
| 865 | error = PTR_ERR(old_dentry); |
Tejun Heo | 456ef15 | 2008-01-16 12:10:53 +0900 | [diff] [blame] | 866 | old_dentry = NULL; |
Eric W. Biederman | 9918f9a | 2007-08-20 21:36:31 +0900 | [diff] [blame] | 867 | goto out; |
Tejun Heo | 5122503 | 2007-06-14 04:27:25 +0900 | [diff] [blame] | 868 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 869 | |
Tejun Heo | ff869de | 2007-08-02 21:38:02 +0900 | [diff] [blame] | 870 | parent = old_dentry->d_parent; |
Tejun Heo | 5122503 | 2007-06-14 04:27:25 +0900 | [diff] [blame] | 871 | |
Eric W. Biederman | 90bc613 | 2007-07-31 19:15:08 +0900 | [diff] [blame] | 872 | /* lock parent and get dentry for new name */ |
| 873 | mutex_lock(&parent->d_inode->i_mutex); |
Eric W. Biederman | 9918f9a | 2007-08-20 21:36:31 +0900 | [diff] [blame] | 874 | mutex_lock(&sysfs_mutex); |
Tejun Heo | 996b737 | 2007-06-14 03:45:14 +0900 | [diff] [blame] | 875 | |
| 876 | error = -EEXIST; |
Eric W. Biederman | 9918f9a | 2007-08-20 21:36:31 +0900 | [diff] [blame] | 877 | if (sysfs_find_dirent(sd->s_parent, new_name)) |
| 878 | goto out_unlock; |
| 879 | |
| 880 | error = -ENOMEM; |
| 881 | new_dentry = d_alloc_name(parent, new_name); |
| 882 | if (!new_dentry) |
Tejun Heo | 5122503 | 2007-06-14 04:27:25 +0900 | [diff] [blame] | 883 | goto out_unlock; |
Tejun Heo | 996b737 | 2007-06-14 03:45:14 +0900 | [diff] [blame] | 884 | |
Eric W. Biederman | 0b4a4fe | 2008-07-03 18:05:28 -0700 | [diff] [blame] | 885 | /* rename sysfs_dirent */ |
Tejun Heo | 0c096b5 | 2007-06-14 03:45:15 +0900 | [diff] [blame] | 886 | error = -ENOMEM; |
| 887 | new_name = dup_name = kstrdup(new_name, GFP_KERNEL); |
| 888 | if (!new_name) |
Eric W. Biederman | 9918f9a | 2007-08-20 21:36:31 +0900 | [diff] [blame] | 889 | goto out_unlock; |
Tejun Heo | 996b737 | 2007-06-14 03:45:14 +0900 | [diff] [blame] | 890 | |
Tejun Heo | 5122503 | 2007-06-14 04:27:25 +0900 | [diff] [blame] | 891 | dup_name = sd->s_name; |
Tejun Heo | 0c096b5 | 2007-06-14 03:45:15 +0900 | [diff] [blame] | 892 | sd->s_name = new_name; |
| 893 | |
Tejun Heo | ff869de | 2007-08-02 21:38:02 +0900 | [diff] [blame] | 894 | /* rename */ |
Tejun Heo | 996b737 | 2007-06-14 03:45:14 +0900 | [diff] [blame] | 895 | d_add(new_dentry, NULL); |
Eric W. Biederman | 5a26b79 | 2007-08-20 21:36:30 +0900 | [diff] [blame] | 896 | d_move(old_dentry, new_dentry); |
Tejun Heo | 996b737 | 2007-06-14 03:45:14 +0900 | [diff] [blame] | 897 | |
Tejun Heo | 996b737 | 2007-06-14 03:45:14 +0900 | [diff] [blame] | 898 | error = 0; |
Tejun Heo | 996b737 | 2007-06-14 03:45:14 +0900 | [diff] [blame] | 899 | out_unlock: |
Eric W. Biederman | 9918f9a | 2007-08-20 21:36:31 +0900 | [diff] [blame] | 900 | mutex_unlock(&sysfs_mutex); |
Eric W. Biederman | 90bc613 | 2007-07-31 19:15:08 +0900 | [diff] [blame] | 901 | mutex_unlock(&parent->d_inode->i_mutex); |
Tejun Heo | 5122503 | 2007-06-14 04:27:25 +0900 | [diff] [blame] | 902 | kfree(dup_name); |
Tejun Heo | 5122503 | 2007-06-14 04:27:25 +0900 | [diff] [blame] | 903 | dput(old_dentry); |
| 904 | dput(new_dentry); |
Eric W. Biederman | 9918f9a | 2007-08-20 21:36:31 +0900 | [diff] [blame] | 905 | out: |
Eric W. Biederman | 932ea2e | 2007-08-20 21:36:30 +0900 | [diff] [blame] | 906 | mutex_unlock(&sysfs_rename_mutex); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 907 | return error; |
| 908 | } |
| 909 | |
Tejun Heo | 5122503 | 2007-06-14 04:27:25 +0900 | [diff] [blame] | 910 | int sysfs_move_dir(struct kobject *kobj, struct kobject *new_parent_kobj) |
Cornelia Huck | 8a82472 | 2006-11-20 17:07:51 +0100 | [diff] [blame] | 911 | { |
Tejun Heo | 5122503 | 2007-06-14 04:27:25 +0900 | [diff] [blame] | 912 | struct sysfs_dirent *sd = kobj->sd; |
| 913 | struct sysfs_dirent *new_parent_sd; |
| 914 | struct dentry *old_parent, *new_parent = NULL; |
| 915 | struct dentry *old_dentry = NULL, *new_dentry = NULL; |
Cornelia Huck | 8a82472 | 2006-11-20 17:07:51 +0100 | [diff] [blame] | 916 | int error; |
| 917 | |
Eric W. Biederman | 932ea2e | 2007-08-20 21:36:30 +0900 | [diff] [blame] | 918 | mutex_lock(&sysfs_rename_mutex); |
Tejun Heo | 5122503 | 2007-06-14 04:27:25 +0900 | [diff] [blame] | 919 | BUG_ON(!sd->s_parent); |
Cornelia Huck | a6a8357 | 2009-10-06 15:33:35 +0200 | [diff] [blame] | 920 | new_parent_sd = (new_parent_kobj && new_parent_kobj->sd) ? |
| 921 | new_parent_kobj->sd : &sysfs_root; |
Cornelia Huck | 8a82472 | 2006-11-20 17:07:51 +0100 | [diff] [blame] | 922 | |
Eric W. Biederman | 45aaae9 | 2007-08-20 21:36:31 +0900 | [diff] [blame] | 923 | error = 0; |
| 924 | if (sd->s_parent == new_parent_sd) |
| 925 | goto out; /* nothing to move */ |
| 926 | |
Tejun Heo | 5122503 | 2007-06-14 04:27:25 +0900 | [diff] [blame] | 927 | /* get dentries */ |
| 928 | old_dentry = sysfs_get_dentry(sd); |
| 929 | if (IS_ERR(old_dentry)) { |
| 930 | error = PTR_ERR(old_dentry); |
Tejun Heo | 456ef15 | 2008-01-16 12:10:53 +0900 | [diff] [blame] | 931 | old_dentry = NULL; |
Eric W. Biederman | 45aaae9 | 2007-08-20 21:36:31 +0900 | [diff] [blame] | 932 | goto out; |
Tejun Heo | 5122503 | 2007-06-14 04:27:25 +0900 | [diff] [blame] | 933 | } |
Eric W. Biederman | 5a26b79 | 2007-08-20 21:36:30 +0900 | [diff] [blame] | 934 | old_parent = old_dentry->d_parent; |
Tejun Heo | 5122503 | 2007-06-14 04:27:25 +0900 | [diff] [blame] | 935 | |
| 936 | new_parent = sysfs_get_dentry(new_parent_sd); |
| 937 | if (IS_ERR(new_parent)) { |
| 938 | error = PTR_ERR(new_parent); |
Tejun Heo | 456ef15 | 2008-01-16 12:10:53 +0900 | [diff] [blame] | 939 | new_parent = NULL; |
Eric W. Biederman | 45aaae9 | 2007-08-20 21:36:31 +0900 | [diff] [blame] | 940 | goto out; |
Tejun Heo | 5122503 | 2007-06-14 04:27:25 +0900 | [diff] [blame] | 941 | } |
| 942 | |
Cornelia Huck | 8a82472 | 2006-11-20 17:07:51 +0100 | [diff] [blame] | 943 | again: |
Tejun Heo | 5122503 | 2007-06-14 04:27:25 +0900 | [diff] [blame] | 944 | mutex_lock(&old_parent->d_inode->i_mutex); |
| 945 | if (!mutex_trylock(&new_parent->d_inode->i_mutex)) { |
| 946 | mutex_unlock(&old_parent->d_inode->i_mutex); |
Cornelia Huck | 8a82472 | 2006-11-20 17:07:51 +0100 | [diff] [blame] | 947 | goto again; |
| 948 | } |
Eric W. Biederman | 45aaae9 | 2007-08-20 21:36:31 +0900 | [diff] [blame] | 949 | mutex_lock(&sysfs_mutex); |
Cornelia Huck | 8a82472 | 2006-11-20 17:07:51 +0100 | [diff] [blame] | 950 | |
Eric W. Biederman | 45aaae9 | 2007-08-20 21:36:31 +0900 | [diff] [blame] | 951 | error = -EEXIST; |
| 952 | if (sysfs_find_dirent(new_parent_sd, sd->s_name)) |
Tejun Heo | 5122503 | 2007-06-14 04:27:25 +0900 | [diff] [blame] | 953 | goto out_unlock; |
Eric W. Biederman | 45aaae9 | 2007-08-20 21:36:31 +0900 | [diff] [blame] | 954 | |
| 955 | error = -ENOMEM; |
| 956 | new_dentry = d_alloc_name(new_parent, sd->s_name); |
| 957 | if (!new_dentry) |
| 958 | goto out_unlock; |
| 959 | |
| 960 | error = 0; |
Cornelia Huck | 8a82472 | 2006-11-20 17:07:51 +0100 | [diff] [blame] | 961 | d_add(new_dentry, NULL); |
Eric W. Biederman | 5a26b79 | 2007-08-20 21:36:30 +0900 | [diff] [blame] | 962 | d_move(old_dentry, new_dentry); |
Cornelia Huck | 8a82472 | 2006-11-20 17:07:51 +0100 | [diff] [blame] | 963 | |
| 964 | /* 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] | 965 | sysfs_unlink_sibling(sd); |
Tejun Heo | 7f7cfff | 2007-06-14 03:45:17 +0900 | [diff] [blame] | 966 | sysfs_get(new_parent_sd); |
Peter Oberparleiter | 0f58b44 | 2009-07-14 17:56:15 +0200 | [diff] [blame] | 967 | drop_nlink(old_parent->d_inode); |
Tejun Heo | 7f7cfff | 2007-06-14 03:45:17 +0900 | [diff] [blame] | 968 | sysfs_put(sd->s_parent); |
| 969 | sd->s_parent = new_parent_sd; |
Peter Oberparleiter | 0f58b44 | 2009-07-14 17:56:15 +0200 | [diff] [blame] | 970 | inc_nlink(new_parent->d_inode); |
Tejun Heo | 0c73f18 | 2007-06-14 03:45:18 +0900 | [diff] [blame] | 971 | sysfs_link_sibling(sd); |
Cornelia Huck | 8a82472 | 2006-11-20 17:07:51 +0100 | [diff] [blame] | 972 | |
Tejun Heo | 5122503 | 2007-06-14 04:27:25 +0900 | [diff] [blame] | 973 | out_unlock: |
Eric W. Biederman | 45aaae9 | 2007-08-20 21:36:31 +0900 | [diff] [blame] | 974 | mutex_unlock(&sysfs_mutex); |
Tejun Heo | 5122503 | 2007-06-14 04:27:25 +0900 | [diff] [blame] | 975 | mutex_unlock(&new_parent->d_inode->i_mutex); |
| 976 | mutex_unlock(&old_parent->d_inode->i_mutex); |
Eric W. Biederman | 45aaae9 | 2007-08-20 21:36:31 +0900 | [diff] [blame] | 977 | out: |
Tejun Heo | 5122503 | 2007-06-14 04:27:25 +0900 | [diff] [blame] | 978 | dput(new_parent); |
| 979 | dput(old_dentry); |
| 980 | dput(new_dentry); |
Eric W. Biederman | 932ea2e | 2007-08-20 21:36:30 +0900 | [diff] [blame] | 981 | mutex_unlock(&sysfs_rename_mutex); |
Cornelia Huck | 8a82472 | 2006-11-20 17:07:51 +0100 | [diff] [blame] | 982 | return error; |
| 983 | } |
| 984 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 985 | /* Relationship between s_mode and the DT_xxx types */ |
| 986 | static inline unsigned char dt_type(struct sysfs_dirent *sd) |
| 987 | { |
| 988 | return (sd->s_mode >> 12) & 15; |
| 989 | } |
| 990 | |
| 991 | static int sysfs_readdir(struct file * filp, void * dirent, filldir_t filldir) |
| 992 | { |
Josef "Jeff" Sipek | f427f5d | 2006-12-08 02:36:36 -0800 | [diff] [blame] | 993 | struct dentry *dentry = filp->f_path.dentry; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 994 | struct sysfs_dirent * parent_sd = dentry->d_fsdata; |
Eric W. Biederman | 3efa65b | 2007-08-20 21:36:30 +0900 | [diff] [blame] | 995 | struct sysfs_dirent *pos; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 996 | ino_t ino; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 997 | |
Eric W. Biederman | 3efa65b | 2007-08-20 21:36:30 +0900 | [diff] [blame] | 998 | if (filp->f_pos == 0) { |
| 999 | ino = parent_sd->s_ino; |
| 1000 | if (filldir(dirent, ".", 1, filp->f_pos, ino, DT_DIR) == 0) |
| 1001 | filp->f_pos++; |
| 1002 | } |
| 1003 | if (filp->f_pos == 1) { |
| 1004 | if (parent_sd->s_parent) |
| 1005 | ino = parent_sd->s_parent->s_ino; |
| 1006 | else |
Eric Sandeen | dc35125 | 2007-06-11 14:02:45 +0900 | [diff] [blame] | 1007 | ino = parent_sd->s_ino; |
Eric W. Biederman | 3efa65b | 2007-08-20 21:36:30 +0900 | [diff] [blame] | 1008 | if (filldir(dirent, "..", 2, filp->f_pos, ino, DT_DIR) == 0) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1009 | filp->f_pos++; |
Eric W. Biederman | 3efa65b | 2007-08-20 21:36:30 +0900 | [diff] [blame] | 1010 | } |
| 1011 | if ((filp->f_pos > 1) && (filp->f_pos < INT_MAX)) { |
| 1012 | mutex_lock(&sysfs_mutex); |
| 1013 | |
| 1014 | /* Skip the dentries we have already reported */ |
Tejun Heo | bc747f3 | 2007-09-20 16:05:12 +0900 | [diff] [blame] | 1015 | pos = parent_sd->s_dir.children; |
Eric W. Biederman | 3efa65b | 2007-08-20 21:36:30 +0900 | [diff] [blame] | 1016 | while (pos && (filp->f_pos > pos->s_ino)) |
| 1017 | pos = pos->s_sibling; |
| 1018 | |
| 1019 | for ( ; pos; pos = pos->s_sibling) { |
| 1020 | const char * name; |
| 1021 | int len; |
| 1022 | |
| 1023 | name = pos->s_name; |
| 1024 | len = strlen(name); |
| 1025 | filp->f_pos = ino = pos->s_ino; |
| 1026 | |
| 1027 | if (filldir(dirent, name, len, filp->f_pos, ino, |
| 1028 | dt_type(pos)) < 0) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1029 | break; |
Eric W. Biederman | 3efa65b | 2007-08-20 21:36:30 +0900 | [diff] [blame] | 1030 | } |
| 1031 | if (!pos) |
| 1032 | filp->f_pos = INT_MAX; |
| 1033 | mutex_unlock(&sysfs_mutex); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1034 | } |
| 1035 | return 0; |
| 1036 | } |
| 1037 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1038 | |
Arjan van de Ven | 4b6f5d2 | 2006-03-28 01:56:42 -0800 | [diff] [blame] | 1039 | const struct file_operations sysfs_dir_operations = { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1040 | .read = generic_read_dir, |
| 1041 | .readdir = sysfs_readdir, |
Christoph Hellwig | 3222a3e | 2008-09-03 21:53:01 +0200 | [diff] [blame] | 1042 | .llseek = generic_file_llseek, |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1043 | }; |