sysfs: separate out sysfs_attach_dentry()

Consolidate sd <-> dentry association into sysfs_attach_dentry() and
call it after dentry and inode are properly set up.  This is in
preparation of sysfs_drop_dentry() updates.

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

3 files changed, 30 insertions, 36 deletions

diff --git a/fs/sysfs/dir.c b/fs/sysfs/dir.c
index e0d377aaf2cc..01eeb4b954b1 100644
--- a/fs/sysfs/dir.c
+++ b/fs/sysfs/dir.c
@@ -142,14 +142,24 @@ struct sysfs_dirent *sysfs_new_dirent(const char *name, umode_t mode, int type)
         return NULL;
 }
 
+static void sysfs_attach_dentry(struct sysfs_dirent *sd, struct dentry *dentry)
+{
+        dentry->d_op = &sysfs_dentry_ops;
+        dentry->d_fsdata = sysfs_get(sd);
+
+        /* protect sd->s_dentry against sysfs_d_iput */
+        spin_lock(&sysfs_lock);
+        sd->s_dentry = dentry;
+        spin_unlock(&sysfs_lock);
+
+        d_rehash(dentry);
+}
+
 void sysfs_attach_dirent(struct sysfs_dirent *sd,
                          struct sysfs_dirent *parent_sd, struct dentry *dentry)
 {
-        if (dentry) {
-                sd->s_dentry = dentry;
-                dentry->d_fsdata = sysfs_get(sd);
-                dentry->d_op = &sysfs_dentry_ops;
-        }
+        if (dentry)
+                sysfs_attach_dentry(sd, dentry);
 
         if (parent_sd) {
                 sd->s_parent = sysfs_get(parent_sd);
@@ -229,15 +239,13 @@ static int create_dir(struct kobject *kobj, struct dentry *parent,
         if (!sd)
                 goto out_drop;
         sd->s_elem.dir.kobj = kobj;
-        sysfs_attach_dirent(sd, parent->d_fsdata, dentry);
 
-        error = sysfs_create(dentry, mode, init_dir);
+        error = sysfs_create(sd, dentry, mode, init_dir);
         if (error)
                 goto out_sput;
 
         inc_nlink(parent->d_inode);
-        dentry->d_op = &sysfs_dentry_ops;
-        d_rehash(dentry);
+        sysfs_attach_dirent(sd, parent->d_fsdata, dentry);
 
         *p_dentry = dentry;
         error = 0;
@@ -308,42 +316,28 @@ static int sysfs_attach_attr(struct sysfs_dirent * sd, struct dentry * dentry)
                 init = init_file;
         }
 
-        dentry->d_fsdata = sysfs_get(sd);
-        /* protect sd->s_dentry against sysfs_d_iput */
-        spin_lock(&sysfs_lock);
-        sd->s_dentry = dentry;
-        spin_unlock(&sysfs_lock);
-        error = sysfs_create(dentry, (attr->mode & S_IALLUGO) | S_IFREG, init);
-        if (error) {
-                sysfs_put(sd);
+        error = sysfs_create(sd, dentry,
+                             (attr->mode & S_IALLUGO) | S_IFREG, init);
+        if (error)
                 return error;
-        }
 
         if (bin_attr) {
                 dentry->d_inode->i_size = bin_attr->size;
                 dentry->d_inode->i_fop = &bin_fops;
         }
-        dentry->d_op = &sysfs_dentry_ops;
-        d_rehash(dentry);
+
+        sysfs_attach_dentry(sd, dentry);
 
         return 0;
 }
 
 static int sysfs_attach_link(struct sysfs_dirent * sd, struct dentry * dentry)
 {
-        int err = 0;
+        int err;
 
-        dentry->d_fsdata = sysfs_get(sd);
-        /* protect sd->s_dentry against sysfs_d_iput */
-        spin_lock(&sysfs_lock);
-        sd->s_dentry = dentry;
-        spin_unlock(&sysfs_lock);
-        err = sysfs_create(dentry, S_IFLNK|S_IRWXUGO, init_symlink);
-        if (!err) {
-                dentry->d_op = &sysfs_dentry_ops;
-                d_rehash(dentry);
-        } else
-                sysfs_put(sd);
+        err = sysfs_create(sd, dentry, S_IFLNK|S_IRWXUGO, init_symlink);
+        if (!err)
+                sysfs_attach_dentry(sd, dentry);
 
         return err;
 }
@@ -773,7 +767,6 @@ struct dentry *sysfs_create_shadow_dir(struct kobject *kobj)
         d_instantiate(shadow, igrab(inode));
         inc_nlink(inode);
         inc_nlink(parent->d_inode);
-        shadow->d_op = &sysfs_dentry_ops;
 
         dget(shadow);           /* Extra count - pin the dentry in core */
 
diff --git a/fs/sysfs/inode.c b/fs/sysfs/inode.c
index d9ccc830b73a..88857a399d0c 100644
--- a/fs/sysfs/inode.c
+++ b/fs/sysfs/inode.c
@@ -156,13 +156,13 @@ struct inode * sysfs_new_inode(mode_t mode, struct sysfs_dirent * sd)
         return inode;
 }
 
-int sysfs_create(struct dentry * dentry, int mode, int (*init)(struct inode *))
+int sysfs_create(struct sysfs_dirent *sd, struct dentry *dentry, int mode,
+                 int (*init)(struct inode *))
 {
         int error = 0;
         struct inode * inode = NULL;
         if (dentry) {
                 if (!dentry->d_inode) {
-                        struct sysfs_dirent * sd = dentry->d_fsdata;
                         if ((inode = sysfs_new_inode(mode, sd))) {
                                 if (dentry->d_parent && dentry->d_parent->d_inode) {
                                         struct inode *p_inode = dentry->d_parent->d_inode;
diff --git a/fs/sysfs/sysfs.h b/fs/sysfs/sysfs.h
index 8b09e9d882c2..9fa77d648aa5 100644
--- a/fs/sysfs/sysfs.h
+++ b/fs/sysfs/sysfs.h
@@ -58,7 +58,8 @@ extern struct kmem_cache *sysfs_dir_cachep;
 
 extern void sysfs_delete_inode(struct inode *inode);
 extern struct inode * sysfs_new_inode(mode_t mode, struct sysfs_dirent *);
-extern int sysfs_create(struct dentry *, int mode, int (*init)(struct inode *));
+extern int sysfs_create(struct sysfs_dirent *sd, struct dentry *dentry,
+                        int mode, int (*init)(struct inode *));
 
 extern void release_sysfs_dirent(struct sysfs_dirent * sd);
 extern int sysfs_dirent_exist(struct sysfs_dirent *, const unsigned char *);