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authorLinus Torvalds <torvalds@woody.linux-foundation.org>2007-07-12 22:40:20 +0200
committerLinus Torvalds <torvalds@woody.linux-foundation.org>2007-07-12 22:40:20 +0200
commitdc690d8ef842b464f1c429a376ca16cb8dbee6ae (patch)
tree77955849af5a15755f5e55e24ae4b9c520583a72 /fs/sysfs/symlink.c
parentMerge branch 'upstream-linus' of master.kernel.org:/pub/scm/linux/kernel/git/... (diff)
parentsysfs: add parameter "struct bin_attribute *" in .read/.write methods for sys... (diff)
downloadlinux-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.c150
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)