Introduce btrfs_iget helper

Date: Mon, 21 Jul 2008 02:01:04 +0530
This patch introduces a btrfs_iget helper to be used in NFS support.

Signed-off-by: Balaji Rao <balajirrao@gmail.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
Signed-off-by: Chris Mason <chris.mason@oracle.com>

diff --git a/fs/btrfs/ctree.h b/fs/btrfs/ctree.h
index 0402133..cecf29e 100644 (file)
--- a/fs/btrfs/ctree.h
+++ b/fs/btrfs/ctree.h
@@ -1700,6 +1700,8 @@ struct inode *btrfs_iget_locked(struct super_block *s, u64 objectid,
                                struct btrfs_root *root);
 struct inode *btrfs_ilookup(struct super_block *s, u64 objectid,
                            u64 root_objectid);
+struct inode *btrfs_iget(struct super_block *s, struct btrfs_key *location,
+                        struct btrfs_root *root, int *is_new);
 int btrfs_commit_write(struct file *file, struct page *page,
                       unsigned from, unsigned to);
 struct extent_map *btrfs_get_extent(struct inode *inode, struct page *page,

diff --git a/fs/btrfs/inode.c b/fs/btrfs/inode.c
index 38d7a81..266ca55 100644 (file)
--- a/fs/btrfs/inode.c
+++ b/fs/btrfs/inode.c
@@ -1840,6 +1840,33 @@ struct inode *btrfs_iget_locked(struct super_block *s, u64 objectid,
        return inode;
 }
 
+/* Get an inode object given its location and corresponding root.
+ * Returns in *is_new if the inode was read from disk
+ */
+struct inode *btrfs_iget(struct super_block *s, struct btrfs_key *location,
+                        struct btrfs_root *root, int *is_new)
+{
+       struct inode *inode;
+
+       inode = btrfs_iget_locked(s, location->objectid, root);
+       if (!inode)
+               return ERR_PTR(-EACCES);
+
+       if (inode->i_state & I_NEW) {
+               BTRFS_I(inode)->root = root;
+               memcpy(&BTRFS_I(inode)->location, location, sizeof(*location));
+               btrfs_read_locked_inode(inode);
+               unlock_new_inode(inode);
+               if (is_new)
+                       *is_new = 1;
+       } else {
+               if (is_new)
+                       *is_new = 0;
+       }
+
+       return inode;
+}
+
 static struct dentry *btrfs_lookup(struct inode *dir, struct dentry *dentry,
                                   struct nameidata *nd)
 {
@@ -1848,7 +1875,7 @@ static struct dentry *btrfs_lookup(struct inode *dir, struct dentry *dentry,
        struct btrfs_root *root = bi->root;
        struct btrfs_root *sub_root = root;
        struct btrfs_key location;
-       int ret, do_orphan = 0;
+       int ret, new, do_orphan = 0;
 
        if (dentry->d_name.len > BTRFS_NAME_LEN)
                return ERR_PTR(-ENAMETOOLONG);
@@ -1866,23 +1893,15 @@ static struct dentry *btrfs_lookup(struct inode *dir, struct dentry *dentry,
                        return ERR_PTR(ret);
                if (ret > 0)
                        return ERR_PTR(-ENOENT);
-
-               inode = btrfs_iget_locked(dir->i_sb, location.objectid,
-                                         sub_root);
-               if (!inode)
-                       return ERR_PTR(-EACCES);
-               if (inode->i_state & I_NEW) {
-                       /* the inode and parent dir are two different roots */
-                       if (sub_root != root) {
-                               igrab(inode);
-                               sub_root->inode = inode;
-                               do_orphan = 1;
-                       }
-                       BTRFS_I(inode)->root = sub_root;
-                       memcpy(&BTRFS_I(inode)->location, &location,
-                              sizeof(location));
-                       btrfs_read_locked_inode(inode);
-                       unlock_new_inode(inode);
+               inode = btrfs_iget(dir->i_sb, &location, sub_root, &new);
+               if (IS_ERR(inode))
+                       return ERR_CAST(inode);
+
+               /* the inode and parent dir are two different roots */
+               if (new && root != sub_root) {
+                       igrab(inode);
+                       sub_root->inode = inode;
+                       do_orphan = 1;
                }
        }