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author | Linus Torvalds <torvalds@woody.linux-foundation.org> | 2007-07-12 22:40:20 +0200 |
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committer | Linus Torvalds <torvalds@woody.linux-foundation.org> | 2007-07-12 22:40:20 +0200 |
commit | dc690d8ef842b464f1c429a376ca16cb8dbee6ae (patch) | |
tree | 77955849af5a15755f5e55e24ae4b9c520583a72 /fs/sysfs/symlink.c | |
parent | Merge branch 'upstream-linus' of master.kernel.org:/pub/scm/linux/kernel/git/... (diff) | |
parent | sysfs: add parameter "struct bin_attribute *" in .read/.write methods for sys... (diff) | |
download | linux-dc690d8ef842b464f1c429a376ca16cb8dbee6ae.tar.xz linux-dc690d8ef842b464f1c429a376ca16cb8dbee6ae.zip |
Merge master.kernel.org:/pub/scm/linux/kernel/git/gregkh/driver-2.6
* master.kernel.org:/pub/scm/linux/kernel/git/gregkh/driver-2.6: (61 commits)
sysfs: add parameter "struct bin_attribute *" in .read/.write methods for sysfs binary attributes
sysfs: make directory dentries and inodes reclaimable
sysfs: implement sysfs_get_dentry()
sysfs: move sysfs_drop_dentry() to dir.c and make it static
sysfs: restructure add/remove paths and fix inode update
sysfs: use sysfs_mutex to protect the sysfs_dirent tree
sysfs: consolidate sysfs spinlocks
sysfs: make kobj point to sysfs_dirent instead of dentry
sysfs: implement sysfs_find_dirent() and sysfs_get_dirent()
sysfs: implement SYSFS_FLAG_REMOVED flag
sysfs: rename sysfs_dirent->s_type to s_flags and make room for flags
sysfs: make sysfs_drop_dentry() access inodes using ilookup()
sysfs: Fix oops in sysfs_drop_dentry on x86_64
sysfs: use singly-linked list for sysfs_dirent tree
sysfs: slim down sysfs_dirent->s_active
sysfs: move s_active functions to fs/sysfs/dir.c
sysfs: fix root sysfs_dirent -> root dentry association
sysfs: use iget_locked() instead of new_inode()
sysfs: reorganize sysfs_new_indoe() and sysfs_create()
sysfs: fix parent refcounting during rename and move
...
Diffstat (limited to 'fs/sysfs/symlink.c')
-rw-r--r-- | fs/sysfs/symlink.c | 150 |
1 files changed, 70 insertions, 80 deletions
diff --git a/fs/sysfs/symlink.c b/fs/sysfs/symlink.c index 7b9c5bfde920..2f86e0422290 100644 --- a/fs/sysfs/symlink.c +++ b/fs/sysfs/symlink.c @@ -11,71 +11,39 @@ #include "sysfs.h" -static int object_depth(struct kobject * kobj) +static int object_depth(struct sysfs_dirent *sd) { - struct kobject * p = kobj; int depth = 0; - do { depth++; } while ((p = p->parent)); + + for (; sd->s_parent; sd = sd->s_parent) + depth++; + return depth; } -static int object_path_length(struct kobject * kobj) +static int object_path_length(struct sysfs_dirent * sd) { - struct kobject * p = kobj; int length = 1; - do { - length += strlen(kobject_name(p)) + 1; - p = p->parent; - } while (p); + + for (; sd->s_parent; sd = sd->s_parent) + length += strlen(sd->s_name) + 1; + return length; } -static void fill_object_path(struct kobject * kobj, char * buffer, int length) +static void fill_object_path(struct sysfs_dirent *sd, char *buffer, int length) { - struct kobject * p; - --length; - for (p = kobj; p; p = p->parent) { - int cur = strlen(kobject_name(p)); + for (; sd->s_parent; sd = sd->s_parent) { + int cur = strlen(sd->s_name); /* back up enough to print this bus id with '/' */ length -= cur; - strncpy(buffer + length,kobject_name(p),cur); + strncpy(buffer + length, sd->s_name, cur); *(buffer + --length) = '/'; } } -static int sysfs_add_link(struct dentry * parent, const char * name, struct kobject * target) -{ - struct sysfs_dirent * parent_sd = parent->d_fsdata; - struct sysfs_symlink * sl; - int error = 0; - - error = -ENOMEM; - sl = kmalloc(sizeof(*sl), GFP_KERNEL); - if (!sl) - goto exit1; - - sl->link_name = kmalloc(strlen(name) + 1, GFP_KERNEL); - if (!sl->link_name) - goto exit2; - - strcpy(sl->link_name, name); - sl->target_kobj = kobject_get(target); - - error = sysfs_make_dirent(parent_sd, NULL, sl, S_IFLNK|S_IRWXUGO, - SYSFS_KOBJ_LINK); - if (!error) - return 0; - - kobject_put(target); - kfree(sl->link_name); -exit2: - kfree(sl); -exit1: - return error; -} - /** * sysfs_create_link - create symlink between two objects. * @kobj: object whose directory we're creating the link in. @@ -84,24 +52,57 @@ exit1: */ int sysfs_create_link(struct kobject * kobj, struct kobject * target, const char * name) { - struct dentry *dentry = NULL; - int error = -EEXIST; + struct sysfs_dirent *parent_sd = NULL; + struct sysfs_dirent *target_sd = NULL; + struct sysfs_dirent *sd = NULL; + struct sysfs_addrm_cxt acxt; + int error; BUG_ON(!name); if (!kobj) { if (sysfs_mount && sysfs_mount->mnt_sb) - dentry = sysfs_mount->mnt_sb->s_root; + parent_sd = sysfs_mount->mnt_sb->s_root->d_fsdata; } else - dentry = kobj->dentry; + parent_sd = kobj->sd; + + error = -EFAULT; + if (!parent_sd) + goto out_put; + + /* target->sd can go away beneath us but is protected with + * sysfs_assoc_lock. Fetch target_sd from it. + */ + spin_lock(&sysfs_assoc_lock); + if (target->sd) + target_sd = sysfs_get(target->sd); + spin_unlock(&sysfs_assoc_lock); + + error = -ENOENT; + if (!target_sd) + goto out_put; + + error = -ENOMEM; + sd = sysfs_new_dirent(name, S_IFLNK|S_IRWXUGO, SYSFS_KOBJ_LINK); + if (!sd) + goto out_put; + sd->s_elem.symlink.target_sd = target_sd; - if (!dentry) - return -EFAULT; + sysfs_addrm_start(&acxt, parent_sd); - mutex_lock(&dentry->d_inode->i_mutex); - if (!sysfs_dirent_exist(dentry->d_fsdata, name)) - error = sysfs_add_link(dentry, name, target); - mutex_unlock(&dentry->d_inode->i_mutex); + if (!sysfs_find_dirent(parent_sd, name)) { + sysfs_add_one(&acxt, sd); + sysfs_link_sibling(sd); + } + + if (sysfs_addrm_finish(&acxt)) + return 0; + + error = -EEXIST; + /* fall through */ + out_put: + sysfs_put(target_sd); + sysfs_put(sd); return error; } @@ -114,17 +115,17 @@ int sysfs_create_link(struct kobject * kobj, struct kobject * target, const char void sysfs_remove_link(struct kobject * kobj, const char * name) { - sysfs_hash_and_remove(kobj->dentry,name); + sysfs_hash_and_remove(kobj->sd, name); } -static int sysfs_get_target_path(struct kobject * kobj, struct kobject * target, - char *path) +static int sysfs_get_target_path(struct sysfs_dirent * parent_sd, + struct sysfs_dirent * target_sd, char *path) { char * s; int depth, size; - depth = object_depth(kobj); - size = object_path_length(target) + depth * 3 - 1; + depth = object_depth(parent_sd); + size = object_path_length(target_sd) + depth * 3 - 1; if (size > PATH_MAX) return -ENAMETOOLONG; @@ -133,7 +134,7 @@ static int sysfs_get_target_path(struct kobject * kobj, struct kobject * target, for (s = path; depth--; s += 3) strcpy(s,"../"); - fill_object_path(target, path, size); + fill_object_path(target_sd, path, size); pr_debug("%s: path = '%s'\n", __FUNCTION__, path); return 0; @@ -141,27 +142,16 @@ static int sysfs_get_target_path(struct kobject * kobj, struct kobject * target, static int sysfs_getlink(struct dentry *dentry, char * path) { - struct kobject *kobj, *target_kobj; - int error = 0; + struct sysfs_dirent *sd = dentry->d_fsdata; + struct sysfs_dirent *parent_sd = sd->s_parent; + struct sysfs_dirent *target_sd = sd->s_elem.symlink.target_sd; + int error; - kobj = sysfs_get_kobject(dentry->d_parent); - if (!kobj) - return -EINVAL; + mutex_lock(&sysfs_mutex); + error = sysfs_get_target_path(parent_sd, target_sd, path); + mutex_unlock(&sysfs_mutex); - target_kobj = sysfs_get_kobject(dentry); - if (!target_kobj) { - kobject_put(kobj); - return -EINVAL; - } - - down_read(&sysfs_rename_sem); - error = sysfs_get_target_path(kobj, target_kobj, path); - up_read(&sysfs_rename_sem); - - kobject_put(kobj); - kobject_put(target_kobj); return error; - } static void *sysfs_follow_link(struct dentry *dentry, struct nameidata *nd) |