NFSD: Clean up the idmapper warning...

[safe/jmp/linux-2.6] / fs / btrfs / export.c

diff --git a/fs/btrfs/export.c b/fs/btrfs/export.c
index a913b9b..9596b40 100644 (file)
--- a/fs/btrfs/export.c
+++ b/fs/btrfs/export.c
@@ -7,15 +7,11 @@
 #include "export.h"
 #include "compat.h"
 
-#if LINUX_VERSION_CODE < KERNEL_VERSION(2,6,28)
-#define FILEID_BTRFS_WITHOUT_PARENT            0x4d
-#define FILEID_BTRFS_WITH_PARENT               0x4e
-#define FILEID_BTRFS_WITH_PARENT_ROOT          0x4f
-#endif
-
-#define BTRFS_FID_SIZE_NON_CONNECTABLE         (offsetof(struct btrfs_fid, parent_objectid)/4)
-#define BTRFS_FID_SIZE_CONNECTABLE             (offsetof(struct btrfs_fid, parent_root_objectid)/4)
-#define BTRFS_FID_SIZE_CONNECTABLE_ROOT                (sizeof(struct btrfs_fid)/4)
+#define BTRFS_FID_SIZE_NON_CONNECTABLE (offsetof(struct btrfs_fid, \
+                                                parent_objectid) / 4)
+#define BTRFS_FID_SIZE_CONNECTABLE (offsetof(struct btrfs_fid, \
+                                            parent_root_objectid) / 4)
+#define BTRFS_FID_SIZE_CONNECTABLE_ROOT (sizeof(struct btrfs_fid) / 4)
 
 static int btrfs_encode_fh(struct dentry *dentry, u32 *fh, int *max_len,
                           int connectable)
@@ -68,15 +64,21 @@ static struct dentry *btrfs_get_dentry(struct super_block *sb, u64 objectid,
 {
        struct btrfs_root *root;
        struct inode *inode;
-       struct dentry *result;
        struct btrfs_key key;
 
+       key.objectid = root_objectid;
+       btrfs_set_key_type(&key, BTRFS_ROOT_ITEM_KEY);
+       key.offset = (u64)-1;
+
+       root = btrfs_read_fs_root_no_name(btrfs_sb(sb)->fs_info, &key);
+       if (IS_ERR(root))
+               return ERR_CAST(root);
+
        key.objectid = objectid;
        btrfs_set_key_type(&key, BTRFS_INODE_ITEM_KEY);
        key.offset = 0;
 
-       root = btrfs_lookup_fs_root(btrfs_sb(sb)->fs_info, root_objectid);
-       inode = btrfs_iget(sb, &key, root, NULL);
+       inode = btrfs_iget(sb, &key, root);
        if (IS_ERR(inode))
                return (void *)inode;
 
@@ -85,11 +87,7 @@ static struct dentry *btrfs_get_dentry(struct super_block *sb, u64 objectid,
                return ERR_PTR(-ESTALE);
        }
 
-       result = d_obtain_alias(inode);
-       if (!result)
-               return ERR_PTR(-ENOMEM);
-
-       return result;
+       return d_obtain_alias(inode);
 }
 
 static struct dentry *btrfs_fh_to_parent(struct super_block *sb, struct fid *fh,
@@ -141,8 +139,6 @@ static struct dentry *btrfs_fh_to_dentry(struct super_block *sb, struct fid *fh,
 static struct dentry *btrfs_get_parent(struct dentry *child)
 {
        struct inode *dir = child->d_inode;
-       struct inode *inode;
-       struct dentry *parent;
        struct btrfs_root *root = BTRFS_I(dir)->root;
        struct btrfs_key key;
        struct btrfs_path *path;
@@ -158,42 +154,45 @@ static struct dentry *btrfs_get_parent(struct dentry *child)
        key.offset = (u64)-1;
 
        ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
+       if (ret < 0) {
+               /* Error */
+               btrfs_free_path(path);
+               return ERR_PTR(ret);
+       }
        leaf = path->nodes[0];
        slot = path->slots[0];
-       if (ret < 0 || slot == 0) {
-               btrfs_free_path(path);
-               goto out;
+       if (ret) {
+               /* btrfs_search_slot() returns the slot where we'd want to
+                  insert a backref for parent inode #0xFFFFFFFFFFFFFFFF.
+                  The _real_ backref, telling us what the parent inode
+                  _actually_ is, will be in the slot _before_ the one
+                  that btrfs_search_slot() returns. */
+               if (!slot) {
+                       /* Unless there is _no_ key in the tree before... */
+                       btrfs_free_path(path);
+                       return ERR_PTR(-EIO);
+               }
+               slot--;
        }
-       /* btrfs_search_slot() returns the slot where we'd want to insert
-          an INODE_REF_KEY for parent inode #0xFFFFFFFFFFFFFFFF. The _real_
-          one, telling us what the parent inode _actually_ is, will be in
-          the slot _before_ the one that btrfs_search_slot() returns. */
-       slot--;
 
        btrfs_item_key_to_cpu(leaf, &key, slot);
        btrfs_free_path(path);
 
        if (key.objectid != dir->i_ino || key.type != BTRFS_INODE_REF_KEY)
-               goto out;
+               return ERR_PTR(-EINVAL);
 
        objectid = key.offset;
 
+       /* If we are already at the root of a subvol, return the real root */
+       if (objectid == dir->i_ino)
+               return dget(dir->i_sb->s_root);
+
        /* Build a new key for the inode item */
        key.objectid = objectid;
        btrfs_set_key_type(&key, BTRFS_INODE_ITEM_KEY);
        key.offset = 0;
 
-       inode = btrfs_iget(root->fs_info->sb, &key, root, NULL);
-
-       parent = d_obtain_alias(inode);
-       if (!parent)
-               parent = ERR_PTR(-ENOMEM);
-
-       return parent;
-
-out:
-       btrfs_free_path(path);
-       return ERR_PTR(-EINVAL);
+       return d_obtain_alias(btrfs_iget(root->fs_info->sb, &key, root));
 }
 
 const struct export_operations btrfs_export_ops = {