sysfs: make sysfs_add_one() automatically check for duplicate entry
Make sysfs_add_one() check for duplicate entry and return -EEXIST if
such entry exists. This simplifies node addition code a bit.
This patch doesn't introduce any noticeable behavior change.
Signed-off-by: Tejun Heo <htejun@gmail.com>
Acked-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
diff --git a/fs/sysfs/dir.c b/fs/sysfs/dir.c
index 354675ad..6206032 100644
--- a/fs/sysfs/dir.c
+++ b/fs/sysfs/dir.c
@@ -491,9 +491,16 @@
*
* LOCKING:
* Determined by sysfs_addrm_start().
+ *
+ * RETURNS:
+ * 0 on success, -EEXIST if entry with the given name already
+ * exists.
*/
-void 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;
+
sd->s_parent = sysfs_get(acxt->parent_sd);
if (sysfs_type(sd) == SYSFS_DIR && acxt->parent_inode)
@@ -502,6 +509,8 @@
acxt->cnt++;
sysfs_link_sibling(sd);
+
+ return 0;
}
/**
@@ -691,6 +700,7 @@
umode_t mode = S_IFDIR| S_IRWXU | S_IRUGO | S_IXUGO;
struct sysfs_addrm_cxt acxt;
struct sysfs_dirent *sd;
+ int rc;
/* allocate */
sd = sysfs_new_dirent(name, mode, SYSFS_DIR);
@@ -700,17 +710,15 @@
/* link in */
sysfs_addrm_start(&acxt, parent_sd);
+ rc = sysfs_add_one(&acxt, sd);
+ sysfs_addrm_finish(&acxt);
- if (!sysfs_find_dirent(parent_sd, name))
- sysfs_add_one(&acxt, sd);
-
- if (!sysfs_addrm_finish(&acxt)) {
+ if (rc == 0)
+ *p_sd = sd;
+ else
sysfs_put(sd);
- return -EEXIST;
- }
- *p_sd = sd;
- return 0;
+ return rc;
}
int sysfs_create_subdir(struct kobject *kobj, const char *name,