sysfs: reorganize sysfs_new_indoe() and sysfs_create()

Reorganize/clean up sysfs_new_inode() and sysfs_create().

* sysfs_init_inode() is separated out from sysfs_new_inode() and is
  responsible for basic initialization.
* sysfs_instantiate() replaces the last step of sysfs_create() and is
  responsible for dentry instantitaion.
* type-specific initialization is moved out to the callers.
* mode is specified only once when creating a sysfs_dirent.
* spurious list_del_init(&sd->s_sibling) dropped from create_dir()

This change is to

* prepare for inode allocation fix.
* separate alloc and init code for synchronization update.
* make dentry/inode initialization more flexible for later changes.

This patch doesn't introduce visible behavior change.

Signed-off-by: Tejun Heo <htejun@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

1 files changed, 10 insertions, 8 deletions

diff --git a/fs/sysfs/mount.c b/fs/sysfs/mount.c
index 37ff9ffc55f0..6d3a6249d21c 100644
--- a/fs/sysfs/mount.c
+++ b/fs/sysfs/mount.c
@@ -29,6 +29,7 @@ static struct sysfs_dirent sysfs_root = {
         .s_sibling      = LIST_HEAD_INIT(sysfs_root.s_sibling),
         .s_children     = LIST_HEAD_INIT(sysfs_root.s_children),
         .s_type         = SYSFS_ROOT,
+        .s_mode         = S_IFDIR | S_IRWXU | S_IRUGO | S_IXUGO,
         .s_iattr        = NULL,
         .s_ino          = 1,
 };
@@ -45,18 +46,19 @@ static int sysfs_fill_super(struct super_block *sb, void *data, int silent)
         sb->s_time_gran = 1;
         sysfs_sb = sb;
 
-        inode = sysfs_new_inode(S_IFDIR | S_IRWXU | S_IRUGO | S_IXUGO,
-                                 &sysfs_root);
-        if (inode) {
-                inode->i_op = &sysfs_dir_inode_operations;
-                inode->i_fop = &sysfs_dir_operations;
-                /* directory inodes start off with i_nlink == 2 (for "." entry) */
-                inc_nlink(inode);
-        } else {
+        inode = new_inode(sysfs_sb);
+        if (!inode) {
                 pr_debug("sysfs: could not get root inode\n");
                 return -ENOMEM;
         }
 
+        sysfs_init_inode(&sysfs_root, inode);
+
+        inode->i_op = &sysfs_dir_inode_operations;
+        inode->i_fop = &sysfs_dir_operations;
+        /* directory inodes start off with i_nlink == 2 (for "." entry) */
+        inc_nlink(inode);
+
         root = d_alloc_root(inode);
         if (!root) {
                 pr_debug("%s: could not get root dentry!\n",__FUNCTION__);