/*
- * dir.c - Operations for sysfs directories.
+ * fs/sysfs/dir.c - sysfs core and dir operation implementation
+ *
+ * Copyright (c) 2001-3 Patrick Mochel
+ * Copyright (c) 2007 SUSE Linux Products GmbH
+ * Copyright (c) 2007 Tejun Heo <teheo@suse.de>
+ *
+ * This file is released under the GPLv2.
+ *
+ * Please see Documentation/filesystems/sysfs.txt for more information.
*/
#undef DEBUG
DEFINE_MUTEX(sysfs_mutex);
DEFINE_MUTEX(sysfs_rename_mutex);
-spinlock_t sysfs_assoc_lock = SPIN_LOCK_UNLOCKED;
+DEFINE_SPINLOCK(sysfs_assoc_lock);
-static spinlock_t sysfs_ino_lock = SPIN_LOCK_UNLOCKED;
+static DEFINE_SPINLOCK(sysfs_ino_lock);
static DEFINE_IDA(sysfs_ino_ida);
/**
* @sd: sysfs_dirent of interest
*
* Link @sd into its sibling list which starts from
- * sd->s_parent->s_children.
+ * sd->s_parent->s_dir.children.
*
* Locking:
* mutex_lock(sysfs_mutex)
/* Store directory entries in order by ino. This allows
* readdir to properly restart without having to add a
- * cursor into the s_children list.
+ * cursor into the s_dir.children list.
*/
- for (pos = &parent_sd->s_children; *pos; pos = &(*pos)->s_sibling) {
+ for (pos = &parent_sd->s_dir.children; *pos; pos = &(*pos)->s_sibling) {
if (sd->s_ino < (*pos)->s_ino)
break;
}
* @sd: sysfs_dirent of interest
*
* Unlink @sd from its sibling list which starts from
- * sd->s_parent->s_children.
+ * sd->s_parent->s_dir.children.
*
* Locking:
* mutex_lock(sysfs_mutex)
{
struct sysfs_dirent **pos;
- for (pos = &sd->s_parent->s_children; *pos; pos = &(*pos)->s_sibling) {
+ for (pos = &sd->s_parent->s_dir.children; *pos;
+ pos = &(*pos)->s_sibling) {
if (*pos == sd) {
*pos = sd->s_sibling;
sd->s_sibling = NULL;
/* look it up */
parent = dentry;
mutex_lock(&parent->d_inode->i_mutex);
- dentry = lookup_one_len_kern(cur->s_name, parent,
- strlen(cur->s_name));
+ dentry = lookup_one_noperm(cur->s_name, parent);
mutex_unlock(&parent->d_inode->i_mutex);
dput(parent);
* RETURNS:
* Pointer to @sd on success, NULL on failure.
*/
-struct sysfs_dirent *sysfs_get_active(struct sysfs_dirent *sd)
+static struct sysfs_dirent *sysfs_get_active(struct sysfs_dirent *sd)
{
if (unlikely(!sd))
return NULL;
* Put an active reference to @sd. This function is noop if @sd
* is NULL.
*/
-void sysfs_put_active(struct sysfs_dirent *sd)
+static void sysfs_put_active(struct sysfs_dirent *sd)
{
struct completion *cmpl;
int v;
parent_sd = sd->s_parent;
if (sysfs_type(sd) == SYSFS_KOBJ_LINK)
- sysfs_put(sd->s_elem.symlink.target_sd);
+ sysfs_put(sd->s_symlink.target_sd);
if (sysfs_type(sd) & SYSFS_COPY_NAME)
kfree(sd->s_name);
kfree(sd->s_iattr);
{
struct sysfs_dirent * sd = dentry->d_fsdata;
- if (sd) {
- /* sd->s_dentry is protected with sysfs_assoc_lock.
- * This allows sysfs_drop_dentry() to dereference it.
- */
- spin_lock(&sysfs_assoc_lock);
-
- /* The dentry might have been deleted or another
- * lookup could have happened updating sd->s_dentry to
- * point the new dentry. Ignore if it isn't pointing
- * to this dentry.
- */
- if (sd->s_dentry == dentry)
- sd->s_dentry = NULL;
- spin_unlock(&sysfs_assoc_lock);
- sysfs_put(sd);
- }
+ sysfs_put(sd);
iput(inode);
}
atomic_set(&sd->s_count, 1);
atomic_set(&sd->s_active, 0);
- atomic_set(&sd->s_event, 1);
sd->s_name = name;
sd->s_mode = mode;
return NULL;
}
-/**
- * sysfs_attach_dentry - associate sysfs_dirent with dentry
- * @sd: target sysfs_dirent
- * @dentry: dentry to associate
- *
- * Associate @sd with @dentry. This is protected by
- * sysfs_assoc_lock to avoid race with sysfs_d_iput().
- *
- * LOCKING:
- * mutex_lock(sysfs_mutex)
- */
-static void sysfs_attach_dentry(struct sysfs_dirent *sd, struct dentry *dentry)
-{
- dentry->d_op = &sysfs_dentry_ops;
- dentry->d_fsdata = sysfs_get(sd);
-
- /* protect sd->s_dentry against sysfs_d_iput */
- spin_lock(&sysfs_assoc_lock);
- sd->s_dentry = dentry;
- spin_unlock(&sysfs_assoc_lock);
-
- d_rehash(dentry);
-}
-
static int sysfs_ilookup_test(struct inode *inode, void *arg)
{
struct sysfs_dirent *sd = arg;
* @sd: sysfs_dirent to be added
*
* Get @acxt->parent_sd and set sd->s_parent to it and increment
- * nlink of parent inode if @sd is a directory. @sd is NOT
- * linked into the children list of the parent. The caller
- * should invoke sysfs_link_sibling() after this function
- * completes if @sd needs to be on the children list.
+ * nlink of parent inode if @sd is a directory and link into the
+ * children list of the parent.
*
* This function should be called between calls to
* sysfs_addrm_start() and sysfs_addrm_finish() and should be
*/
int sysfs_add_one(struct sysfs_addrm_cxt *acxt, struct sysfs_dirent *sd)
{
- if (sysfs_find_dirent(acxt->parent_sd, sd->s_name))
+ if (sysfs_find_dirent(acxt->parent_sd, sd->s_name)) {
+ printk(KERN_WARNING "sysfs: duplicate filename '%s' "
+ "can not be created\n", sd->s_name);
+ WARN_ON(1);
return -EEXIST;
+ }
sd->s_parent = sysfs_get(acxt->parent_sd);
* @sd: sysfs_dirent to be added
*
* Mark @sd removed and drop nlink of parent inode if @sd is a
- * directory. @sd is NOT unlinked from the children list of the
- * parent. The caller is repsonsible for removing @sd from the
- * children list before calling this function.
+ * directory. @sd is unlinked from the children list.
*
* This function should be called between calls to
* sysfs_addrm_start() and sysfs_addrm_finish() and should be
{
struct sysfs_dirent *sd;
- for (sd = parent_sd->s_children; sd; sd = sd->s_sibling)
+ for (sd = parent_sd->s_dir.children; sd; sd = sd->s_sibling)
if (!strcmp(sd->s_name, name))
return sd;
return NULL;
sd = sysfs_new_dirent(name, mode, SYSFS_DIR);
if (!sd)
return -ENOMEM;
- sd->s_elem.dir.kobj = kobj;
+ sd->s_dir.kobj = kobj;
/* link in */
sysfs_addrm_start(&acxt, parent_sd);
sd = sysfs_find_dirent(parent_sd, dentry->d_name.name);
/* no such entry */
- if (!sd)
+ if (!sd) {
+ ret = ERR_PTR(-ENOENT);
goto out_unlock;
+ }
/* attach dentry and inode */
inode = sysfs_get_inode(sd);
goto out_unlock;
}
+ /* instantiate and hash dentry */
+ dentry->d_op = &sysfs_dentry_ops;
+ dentry->d_fsdata = sysfs_get(sd);
d_instantiate(dentry, inode);
- sysfs_attach_dentry(sd, dentry);
+ d_rehash(dentry);
out_unlock:
mutex_unlock(&sysfs_mutex);
pr_debug("sysfs %s: removing dir\n", dir_sd->s_name);
sysfs_addrm_start(&acxt, dir_sd);
- pos = &dir_sd->s_children;
+ pos = &dir_sd->s_dir.children;
while (*pos) {
struct sysfs_dirent *sd = *pos;
int sysfs_rename_dir(struct kobject * kobj, const char *new_name)
{
- struct sysfs_dirent *sd;
+ struct sysfs_dirent *sd = kobj->sd;
struct dentry *parent = NULL;
struct dentry *old_dentry = NULL, *new_dentry = NULL;
const char *dup_name = NULL;
mutex_lock(&sysfs_rename_mutex);
+ error = 0;
+ if (strcmp(sd->s_name, new_name) == 0)
+ goto out; /* nothing to rename */
+
/* get the original dentry */
- sd = kobj->sd;
old_dentry = sysfs_get_dentry(sd);
if (IS_ERR(old_dentry)) {
error = PTR_ERR(old_dentry);
- goto out_dput;
+ old_dentry = NULL;
+ goto out;
}
parent = old_dentry->d_parent;
/* lock parent and get dentry for new name */
mutex_lock(&parent->d_inode->i_mutex);
+ mutex_lock(&sysfs_mutex);
- new_dentry = lookup_one_len(new_name, parent, strlen(new_name));
- if (IS_ERR(new_dentry)) {
- error = PTR_ERR(new_dentry);
- goto out_unlock;
- }
-
- error = -EINVAL;
- if (old_dentry == new_dentry)
+ error = -EEXIST;
+ if (sysfs_find_dirent(sd->s_parent, new_name))
goto out_unlock;
- error = -EEXIST;
- if (new_dentry->d_inode)
+ error = -ENOMEM;
+ new_dentry = d_alloc_name(parent, new_name);
+ if (!new_dentry)
goto out_unlock;
/* rename kobject and sysfs_dirent */
error = -ENOMEM;
new_name = dup_name = kstrdup(new_name, GFP_KERNEL);
if (!new_name)
- goto out_drop;
+ goto out_unlock;
error = kobject_set_name(kobj, "%s", new_name);
if (error)
- goto out_drop;
+ goto out_unlock;
- mutex_lock(&sysfs_mutex);
dup_name = sd->s_name;
sd->s_name = new_name;
- mutex_unlock(&sysfs_mutex);
/* rename */
d_add(new_dentry, NULL);
- d_move(sd->s_dentry, new_dentry);
+ d_move(old_dentry, new_dentry);
error = 0;
- goto out_unlock;
-
- out_drop:
- d_drop(new_dentry);
out_unlock:
+ mutex_unlock(&sysfs_mutex);
mutex_unlock(&parent->d_inode->i_mutex);
- out_dput:
kfree(dup_name);
dput(old_dentry);
dput(new_dentry);
+ out:
mutex_unlock(&sysfs_rename_mutex);
return error;
}
BUG_ON(!sd->s_parent);
new_parent_sd = new_parent_kobj->sd ? new_parent_kobj->sd : &sysfs_root;
+ error = 0;
+ if (sd->s_parent == new_parent_sd)
+ goto out; /* nothing to move */
+
/* get dentries */
old_dentry = sysfs_get_dentry(sd);
if (IS_ERR(old_dentry)) {
error = PTR_ERR(old_dentry);
- goto out_dput;
+ old_dentry = NULL;
+ goto out;
}
- old_parent = sd->s_parent->s_dentry;
+ old_parent = old_dentry->d_parent;
new_parent = sysfs_get_dentry(new_parent_sd);
if (IS_ERR(new_parent)) {
error = PTR_ERR(new_parent);
- goto out_dput;
+ new_parent = NULL;
+ goto out;
}
- if (old_parent->d_inode == new_parent->d_inode) {
- error = 0;
- goto out_dput; /* nothing to move */
- }
again:
mutex_lock(&old_parent->d_inode->i_mutex);
if (!mutex_trylock(&new_parent->d_inode->i_mutex)) {
mutex_unlock(&old_parent->d_inode->i_mutex);
goto again;
}
+ mutex_lock(&sysfs_mutex);
+
+ error = -EEXIST;
+ if (sysfs_find_dirent(new_parent_sd, sd->s_name))
+ goto out_unlock;
- new_dentry = lookup_one_len(kobject_name(kobj), new_parent, strlen(kobject_name(kobj)));
- if (IS_ERR(new_dentry)) {
- error = PTR_ERR(new_dentry);
+ error = -ENOMEM;
+ new_dentry = d_alloc_name(new_parent, sd->s_name);
+ if (!new_dentry)
goto out_unlock;
- } else
- error = 0;
+
+ error = 0;
d_add(new_dentry, NULL);
- d_move(sd->s_dentry, new_dentry);
- dput(new_dentry);
+ d_move(old_dentry, new_dentry);
/* Remove from old parent's list and insert into new parent's list. */
- mutex_lock(&sysfs_mutex);
-
sysfs_unlink_sibling(sd);
sysfs_get(new_parent_sd);
sysfs_put(sd->s_parent);
sd->s_parent = new_parent_sd;
sysfs_link_sibling(sd);
- mutex_unlock(&sysfs_mutex);
-
out_unlock:
+ mutex_unlock(&sysfs_mutex);
mutex_unlock(&new_parent->d_inode->i_mutex);
mutex_unlock(&old_parent->d_inode->i_mutex);
- out_dput:
+ out:
dput(new_parent);
dput(old_dentry);
dput(new_dentry);
mutex_lock(&sysfs_mutex);
/* Skip the dentries we have already reported */
- pos = parent_sd->s_children;
+ pos = parent_sd->s_dir.children;
while (pos && (filp->f_pos > pos->s_ino))
pos = pos->s_sibling;
projects / linux-2.6-omap-h63xx.git / blobdiff