[PATCH 03/11] sysfs: Implement __sysfs_get_dentry

Benjamin Thery
2008-06-06T15:48:47Z

sysfs: Implement __sysfs_get_dentry

This function is similar but much simpler to sysfs_get_dentry
returns a sysfs dentry if one curently exists.

Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Signed-off-by: Benjamin Thery <benjamin.thery@bull.net>
---
fs/sysfs/dir.c | 39 +++++++++++++++++++++++++++++++++++++++
1 file changed, 39 insertions(+)

Index: linux-mm/fs/sysfs/dir.c
===================================================================
--- linux-mm.orig/fs/sysfs/dir.c
+++ linux-mm/fs/sysfs/dir.c
@@ -777,6 +777,45 @@ void sysfs_remove_dir(struct kobject * k
__sysfs_remove_dir(sd);
}

+/**
+ * __sysfs_get_dentry - get dentry for the given sysfs_dirent
+ * @sb: superblock of the dentry to return
+ * @sd: sysfs_dirent of interest
+ *
+ * Get dentry for @sd. Only return a dentry if one currently
+ * exists.
+ *
+ * LOCKING:
+ * Kernel thread context (may sleep)
+ *
+ * RETURNS:
+ * Pointer to found dentry on success, NULL on failure.
+ */
+static struct dentry *__sysfs_get_dentry(struct super_block *sb,
+ struct sysfs_dirent *sd)
+{
+ struct inode *inode;
+ struct dentry *dentry = NULL;
+
+ inode = ilookup5_nowait(sysfs_sb, sd->s_ino, sysfs_ilookup_test, sd);
+ if (inode && !(inode->i_state & I_NEW)) {
+ struct dentry *alias;
+ spin_lock(&dcache_lock);
+ list_for_each_entry(alias, &inode->i_dentry, d_alias) {
+ if (!IS_ROOT(alias) && d_unhashed(alias))
+ continue;
+ if (alias->d_sb != sb)
+ continue;
+ dentry = alias;
+ dget_locked(dentry);
+ break;
+ }
+ spin_unlock(&dcache_lock);
+ }
+ iput(inode);
+ return dentry;
+}
+
int sysfs_rename_dir(struct kobject * kobj, const char *new_name)
{
struct sysfs_dirent *sd = kobj->sd;

--