Btrfs: rename

Signed-off-by: Chris Mason <chris.mason@oracle.com>

4 files changed, 143 insertions, 18 deletions

diff --git a/fs/btrfs/TODO b/fs/btrfs/TODO
index f6df246f26c3..861e34ae0979 100644
--- a/fs/btrfs/TODO
+++ b/fs/btrfs/TODO
@@ -8,6 +8,7 @@
 * Add generation number to key pointer in nodes
 * Add generation number to inode
 * Add ability to switch a block group from data to metadata or vice versa
+* forbid cross subvolume renames and hardlinks
 * Release
 * Do real tree locking
 * Add extent mirroring (backup copies of blocks)
diff --git a/fs/btrfs/ctree.h b/fs/btrfs/ctree.h
index da12d8275817..3330004af1a6 100644
--- a/fs/btrfs/ctree.h
+++ b/fs/btrfs/ctree.h
@@ -32,6 +32,7 @@ extern struct kmem_cache *btrfs_path_cachep;
 #define BTRFS_CSUM_SIZE 32
 /* four bytes for CRC32 */
 #define BTRFS_CRC32_SIZE 4
+#define BTRFS_EMPTY_DIR_SIZE 6
 
 /*
  * the key defines the order in the tree, and so it also defines (optimal)
diff --git a/fs/btrfs/dir-item.c b/fs/btrfs/dir-item.c
index 00a28d90fea6..b408a3d20c7b 100644
--- a/fs/btrfs/dir-item.c
+++ b/fs/btrfs/dir-item.c
@@ -9,7 +9,9 @@ static struct btrfs_dir_item *insert_with_overflow(struct btrfs_trans_handle
                                                    struct btrfs_root *root,
                                                    struct btrfs_path *path,
                                                    struct btrfs_key *cpu_key,
-                                                   u32 data_size)
+                                                   u32 data_size,
+                                                   const char *name,
+                                                   int name_len)
 {
         int ret;
         char *ptr;
@@ -18,6 +20,10 @@ static struct btrfs_dir_item *insert_with_overflow(struct btrfs_trans_handle
 
         ret = btrfs_insert_empty_item(trans, root, path, cpu_key, data_size);
         if (ret == -EEXIST) {
+                struct btrfs_dir_item *di;
+                di = btrfs_match_dir_item_name(root, path, name, name_len);
+                if (di)
+                        return ERR_PTR(-EEXIST);
                 ret = btrfs_extend_item(trans, root, path, data_size);
                 WARN_ON(ret > 0);
                 if (ret)
@@ -37,6 +43,7 @@ int btrfs_insert_dir_item(struct btrfs_trans_handle *trans, struct btrfs_root
                           struct btrfs_key *location, u8 type)
 {
         int ret = 0;
+        int ret2 = 0;
         struct btrfs_path *path;
         struct btrfs_dir_item *dir_item;
         char *name_ptr;
@@ -51,9 +58,12 @@ int btrfs_insert_dir_item(struct btrfs_trans_handle *trans, struct btrfs_root
         path = btrfs_alloc_path();
         btrfs_init_path(path);
         data_size = sizeof(*dir_item) + name_len;
-        dir_item = insert_with_overflow(trans, root, path, &key, data_size);
+        dir_item = insert_with_overflow(trans, root, path, &key, data_size,
+                                        name, name_len);
         if (IS_ERR(dir_item)) {
                 ret = PTR_ERR(dir_item);
+                if (ret == -EEXIST)
+                        goto second_insert;
                 goto out;
         }
 
@@ -66,19 +76,20 @@ int btrfs_insert_dir_item(struct btrfs_trans_handle *trans, struct btrfs_root
         btrfs_memcpy(root, path->nodes[0]->b_data, name_ptr, name, name_len);
         btrfs_mark_buffer_dirty(path->nodes[0]);
 
+second_insert:
         /* FIXME, use some real flag for selecting the extra index */
         if (root == root->fs_info->tree_root) {
                 ret = 0;
                 goto out;
         }
-
         btrfs_release_path(root, path);
 
         btrfs_set_key_type(&key, BTRFS_DIR_INDEX_KEY);
         key.offset = location->objectid;
-        dir_item = insert_with_overflow(trans, root, path, &key, data_size);
+        dir_item = insert_with_overflow(trans, root, path, &key, data_size,
+                                        name, name_len);
         if (IS_ERR(dir_item)) {
-                ret = PTR_ERR(dir_item);
+                ret2 = PTR_ERR(dir_item);
                 goto out;
         }
         btrfs_cpu_key_to_disk(&dir_item->location, location);
@@ -90,7 +101,11 @@ int btrfs_insert_dir_item(struct btrfs_trans_handle *trans, struct btrfs_root
         btrfs_mark_buffer_dirty(path->nodes[0]);
 out:
         btrfs_free_path(path);
-        return ret;
+        if (ret)
+                return ret;
+        if (ret2)
+                return ret2;
+        return 0;
 }
 
 struct btrfs_dir_item *btrfs_lookup_dir_item(struct btrfs_trans_handle *trans,
diff --git a/fs/btrfs/super.c b/fs/btrfs/super.c
index 0220c82841ad..f49cad603ee8 100644
--- a/fs/btrfs/super.c
+++ b/fs/btrfs/super.c
@@ -375,6 +375,7 @@ static int btrfs_truncate_in_trans(struct btrfs_trans_handle *trans,
         struct btrfs_path *path;
         struct btrfs_key key;
         struct btrfs_disk_key *found_key;
+        u32 found_type;
         struct btrfs_leaf *leaf;
         struct btrfs_file_extent_item *fi = NULL;
         u64 extent_start = 0;
@@ -386,12 +387,7 @@ static int btrfs_truncate_in_trans(struct btrfs_trans_handle *trans,
         /* FIXME, add redo link to tree so we don't leak on crash */
         key.objectid = inode->i_ino;
         key.offset = (u64)-1;
-        key.flags = 0;
-        /*
-         * use BTRFS_CSUM_ITEM_KEY because it is larger than inline keys
-         * or extent data
-         */
-        btrfs_set_key_type(&key, BTRFS_CSUM_ITEM_KEY);
+        key.flags = (u32)-1;
         while(1) {
                 btrfs_init_path(path);
                 ret = btrfs_search_slot(trans, root, &key, path, -1, 1);
@@ -405,10 +401,13 @@ static int btrfs_truncate_in_trans(struct btrfs_trans_handle *trans,
                 reada_truncate(root, path, inode->i_ino);
                 leaf = btrfs_buffer_leaf(path->nodes[0]);
                 found_key = &leaf->items[path->slots[0]].key;
+                found_type = btrfs_disk_key_type(found_key);
                 if (btrfs_disk_key_objectid(found_key) != inode->i_ino)
                         break;
-                if (btrfs_disk_key_type(found_key) != BTRFS_CSUM_ITEM_KEY &&
-                    btrfs_disk_key_type(found_key) != BTRFS_EXTENT_DATA_KEY)
+                if (found_type != BTRFS_CSUM_ITEM_KEY &&
+                    found_type != BTRFS_DIR_ITEM_KEY &&
+                    found_type != BTRFS_DIR_INDEX_KEY &&
+                    found_type != BTRFS_EXTENT_DATA_KEY)
                         break;
                 if (btrfs_disk_key_offset(found_key) < inode->i_size)
                         break;
@@ -460,10 +459,8 @@ static void btrfs_delete_inode(struct inode *inode)
         mutex_lock(&root->fs_info->fs_mutex);
         trans = btrfs_start_transaction(root, 1);
         btrfs_set_trans_block_group(trans, inode);
-        if (S_ISREG(inode->i_mode)) {
-                ret = btrfs_truncate_in_trans(trans, root, inode);
-                BUG_ON(ret);
-        }
+        ret = btrfs_truncate_in_trans(trans, root, inode);
+        BUG_ON(ret);
         btrfs_free_inode(trans, root, inode);
         btrfs_end_transaction(trans, root);
         mutex_unlock(&root->fs_info->fs_mutex);
@@ -2504,6 +2501,116 @@ static int btrfs_statfs(struct dentry *dentry, struct kstatfs *buf)
         return 0;
 }
 
+static int btrfs_rename(struct inode * old_dir, struct dentry *old_dentry,
+                           struct inode * new_dir,struct dentry *new_dentry)
+{
+        struct btrfs_trans_handle *trans;
+        struct btrfs_root *root = BTRFS_I(old_dir)->root;
+        struct inode *new_inode = new_dentry->d_inode;
+        struct inode *old_inode = old_dentry->d_inode;
+        struct timespec ctime = CURRENT_TIME;
+        struct btrfs_path *path;
+        struct btrfs_dir_item *di;
+        int ret;
+
+        if (S_ISDIR(old_inode->i_mode) && new_inode &&
+            new_inode->i_size > BTRFS_EMPTY_DIR_SIZE) {
+                return -ENOTEMPTY;
+        }
+        mutex_lock(&root->fs_info->fs_mutex);
+        trans = btrfs_start_transaction(root, 1);
+        btrfs_set_trans_block_group(trans, new_dir);
+        path = btrfs_alloc_path();
+        if (!path) {
+                ret = -ENOMEM;
+                goto out_fail;
+        }
+
+        old_dentry->d_inode->i_nlink++;
+        old_dir->i_ctime = old_dir->i_mtime = ctime;
+        new_dir->i_ctime = new_dir->i_mtime = ctime;
+        old_inode->i_ctime = ctime;
+        if (S_ISDIR(old_inode->i_mode) && old_dir != new_dir) {
+                struct btrfs_key *location = &BTRFS_I(new_dir)->location;
+                u64 old_parent_oid;
+                di = btrfs_lookup_dir_item(trans, root, path, old_inode->i_ino,
+                                           "..", 2, -1);
+                if (IS_ERR(di)) {
+                        ret = PTR_ERR(di);
+                        goto out_fail;
+                }
+                if (!di) {
+                        ret = -ENOENT;
+                        goto out_fail;
+                }
+                old_parent_oid = btrfs_disk_key_objectid(&di->location);
+                ret = btrfs_del_item(trans, root, path);
+                if (ret) {
+                        ret = -EIO;
+                        goto out_fail;
+                }
+                btrfs_release_path(root, path);
+
+                di = btrfs_lookup_dir_index_item(trans, root, path,
+                                                 old_inode->i_ino,
+                                                 old_parent_oid,
+                                                 "..", 2, -1);
+                if (IS_ERR(di)) {
+                        ret = PTR_ERR(di);
+                        goto out_fail;
+                }
+                if (!di) {
+                        ret = -ENOENT;
+                        goto out_fail;
+                }
+                ret = btrfs_del_item(trans, root, path);
+                if (ret) {
+                        ret = -EIO;
+                        goto out_fail;
+                }
+                btrfs_release_path(root, path);
+
+                ret = btrfs_insert_dir_item(trans, root, "..", 2,
+                                            old_inode->i_ino, location, 0);
+                if (ret)
+                        goto out_fail;
+        }
+
+
+        ret = btrfs_add_link(trans, new_dentry, old_inode);
+        if (ret == -EEXIST && new_inode)
+                ret = 0;
+        else if (ret)
+                goto out_fail;
+
+        ret = btrfs_unlink_trans(trans, root, old_dir, old_dentry);
+        if (ret)
+                goto out_fail;
+
+        if (new_inode) {
+                new_inode->i_ctime = CURRENT_TIME;
+                di = btrfs_lookup_dir_index_item(trans, root, path,
+                                                 new_dir->i_ino,
+                                                 new_inode->i_ino,
+                                                 new_dentry->d_name.name,
+                                                 new_dentry->d_name.len, -1);
+                if (di && !IS_ERR(di)) {
+                        btrfs_del_item(trans, root, path);
+                        btrfs_release_path(root, path);
+                }
+                if (S_ISDIR(new_inode->i_mode))
+                        clear_nlink(new_inode);
+                else
+                        drop_nlink(new_inode);
+                btrfs_update_inode(trans, root, new_inode);
+        }
+out_fail:
+        btrfs_free_path(path);
+        btrfs_end_transaction(trans, root);
+        mutex_unlock(&root->fs_info->fs_mutex);
+        return ret;
+}
+
 static struct file_system_type btrfs_fs_type = {
         .owner          = THIS_MODULE,
         .name           = "btrfs",
@@ -2531,6 +2638,7 @@ static struct inode_operations btrfs_dir_inode_operations = {
         .unlink         = btrfs_unlink,
         .mkdir          = btrfs_mkdir,
         .rmdir          = btrfs_rmdir,
+        .rename         = btrfs_rename,
 };
 
 static struct inode_operations btrfs_dir_ro_inode_operations = {