/*
- * 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
#include <linux/idr.h>
#include <linux/completion.h>
#include <linux/mutex.h>
+#include <linux/slab.h>
#include "sysfs.h"
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);
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
- *
- * 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);
- d_rehash(dentry);
-}
-
static int sysfs_ilookup_test(struct inode *inode, void *arg)
{
struct sysfs_dirent *sd = arg;
memset(acxt, 0, sizeof(*acxt));
acxt->parent_sd = parent_sd;
- /* Lookup parent inode. inode initialization and I_NEW
- * clearing are protected by sysfs_mutex. By grabbing it and
- * looking up with _nowait variant, inode state can be
- * determined reliably.
+ /* Lookup parent inode. inode initialization is protected by
+ * sysfs_mutex, so inode existence can be determined by
+ * looking up inode while holding sysfs_mutex.
*/
mutex_lock(&sysfs_mutex);
- inode = ilookup5_nowait(sysfs_sb, parent_sd->s_ino, sysfs_ilookup_test,
- parent_sd);
+ inode = ilookup5(sysfs_sb, parent_sd->s_ino, sysfs_ilookup_test,
+ parent_sd);
+ if (inode) {
+ WARN_ON(inode->i_state & I_NEW);
- if (inode && !(inode->i_state & I_NEW)) {
/* parent inode available */
acxt->parent_inode = inode;
mutex_lock(&inode->i_mutex);
mutex_lock(&sysfs_mutex);
}
- } else
- iput(inode);
+ }
}
/**
- * sysfs_add_one - add sysfs_dirent to parent
+ * __sysfs_add_one - add sysfs_dirent to parent without warning
* @acxt: addrm context to use
* @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
* 0 on success, -EEXIST if entry with the given name already
* exists.
*/
-int sysfs_add_one(struct sysfs_addrm_cxt *acxt, struct sysfs_dirent *sd)
+int __sysfs_add_one(struct sysfs_addrm_cxt *acxt, struct sysfs_dirent *sd)
{
if (sysfs_find_dirent(acxt->parent_sd, sd->s_name))
return -EEXIST;
}
/**
- * sysfs_remove_one - remove sysfs_dirent from parent
+ * sysfs_add_one - add sysfs_dirent to parent
* @acxt: addrm context to use
* @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 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
+ * passed the same @acxt as passed to sysfs_addrm_start().
+ *
+ * LOCKING:
+ * Determined by sysfs_addrm_start().
+ *
+ * RETURNS:
+ * 0 on success, -EEXIST if entry with the given name already
+ * exists.
+ */
+int sysfs_add_one(struct sysfs_addrm_cxt *acxt, struct sysfs_dirent *sd)
+{
+ int ret;
+
+ ret = __sysfs_add_one(acxt, sd);
+ WARN(ret == -EEXIST, KERN_WARNING "sysfs: duplicate filename '%s' "
+ "can not be created\n", sd->s_name);
+ return ret;
+}
+
+/**
+ * sysfs_remove_one - remove sysfs_dirent from parent
+ * @acxt: addrm context to use
+ * @sd: sysfs_dirent to be removed
+ *
* 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;
return sd;
}
+EXPORT_SYMBOL_GPL(sysfs_get_dirent);
static int create_dir(struct kobject *kobj, struct sysfs_dirent *parent_sd,
const char *name, struct sysfs_dirent **p_sd)
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;
old_dentry = sysfs_get_dentry(sd);
if (IS_ERR(old_dentry)) {
error = PTR_ERR(old_dentry);
+ old_dentry = NULL;
goto out;
}
if (!new_dentry)
goto out_unlock;
- /* rename kobject and sysfs_dirent */
+ /* rename sysfs_dirent */
error = -ENOMEM;
new_name = dup_name = kstrdup(new_name, GFP_KERNEL);
if (!new_name)
goto out_unlock;
- error = kobject_set_name(kobj, "%s", new_name);
- if (error)
- goto out_unlock;
-
dup_name = sd->s_name;
sd->s_name = new_name;
old_dentry = sysfs_get_dentry(sd);
if (IS_ERR(old_dentry)) {
error = PTR_ERR(old_dentry);
+ old_dentry = NULL;
goto out;
}
old_parent = old_dentry->d_parent;
new_parent = sysfs_get_dentry(new_parent_sd);
if (IS_ERR(new_parent)) {
error = PTR_ERR(new_parent);
+ new_parent = NULL;
goto out;
}
error = 0;
d_add(new_dentry, NULL);
d_move(old_dentry, new_dentry);
- dput(new_dentry);
/* Remove from old parent's list and insert into new parent's list. */
sysfs_unlink_sibling(sd);
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;
const struct file_operations sysfs_dir_operations = {
.read = generic_read_dir,
.readdir = sysfs_readdir,
+ .llseek = generic_file_llseek,
};
git://ftp.safe.ca / safe / jmp / linux-2.6 / blobdiff