sysfs: use ilookup5() instead of ilookup5_nowait()

As inode creation is protected by sysfs_mutex, ilookup5_nowait()
always either fails to find at all or finds one which is fully
initialized, so using ilookup5_nowait() or ilookup5() doesn't make any
difference.  Switch to ilookup5() as it's planned to be removed.  This
change also makes lookup return value handling a bit simpler.

This change was suggested by Al Viro.

Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Al Viro <viro@hera.kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

1 files changed, 8 insertions, 9 deletions

diff --git a/fs/sysfs/dir.c b/fs/sysfs/dir.c
index 53bc7fc31af3..c18342641cec 100644
--- a/fs/sysfs/dir.c
+++ b/fs/sysfs/dir.c
@@ -370,17 +370,17 @@ void sysfs_addrm_start(struct sysfs_addrm_cxt *acxt,
         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;
 
@@ -393,8 +393,7 @@ void sysfs_addrm_start(struct sysfs_addrm_cxt *acxt,
                         mutex_lock(&inode->i_mutex);
                         mutex_lock(&sysfs_mutex);
                 }
-        } else
-                iput(inode);
+        }
 }
 
 /**