Btrfs: unlink and delete_inode

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

diff --git a/fs/btrfs/super.c b/fs/btrfs/super.c
index 094a66c..f96bd92 100644 (file)
--- a/fs/btrfs/super.c
+++ b/fs/btrfs/super.c
@@ -187,6 +187,104 @@ static void btrfs_read_locked_inode(struct inode *inode)
        return;
 }
 
+static int btrfs_unlink(struct inode *dir, struct dentry *dentry)
+{
+       struct btrfs_path path;
+       struct btrfs_root *root;
+       struct btrfs_trans_handle *trans;
+       const char *name = dentry->d_name.name;
+       int name_len = dentry->d_name.len;
+       int ret;
+       u64 objectid;
+       struct btrfs_dir_item *di;
+
+       btrfs_init_path(&path);
+       root = btrfs_sb(dir->i_sb);
+       mutex_lock(&root->fs_info->fs_mutex);
+       trans = btrfs_start_transaction(root, 1);
+
+       ret = btrfs_lookup_dir_item(trans, root, &path, dir->i_ino,
+                                   name, name_len, -1);
+       if (ret < 0)
+               goto err;
+       if (ret > 0) {
+               ret = -ENOENT;
+               goto err;
+       }
+       di = btrfs_item_ptr(btrfs_buffer_leaf(path.nodes[0]), path.slots[0],
+                           struct btrfs_dir_item);
+       objectid = btrfs_dir_objectid(di);
+
+       ret = btrfs_del_item(trans, root, &path);
+       BUG_ON(ret);
+       dentry->d_inode->i_ctime = dir->i_ctime;
+err:
+       btrfs_release_path(root, &path);
+       btrfs_end_transaction(trans, root);
+       mutex_unlock(&root->fs_info->fs_mutex);
+       if (ret == 0)
+               inode_dec_link_count(dentry->d_inode);
+       return ret;
+}
+
+static int btrfs_free_inode(struct btrfs_trans_handle *trans,
+                           struct btrfs_root *root,
+                           struct inode *inode)
+{
+       u64 objectid = inode->i_ino;
+       struct btrfs_path path;
+       struct btrfs_inode_map_item *map;
+       struct btrfs_key stat_data_key;
+       int ret;
+       clear_inode(inode);
+       btrfs_init_path(&path);
+       ret = btrfs_lookup_inode_map(trans, root, &path, objectid, -1);
+       if (ret) {
+               if (ret > 0)
+                       ret = -ENOENT;
+               btrfs_release_path(root, &path);
+               goto error;
+       }
+       map = btrfs_item_ptr(btrfs_buffer_leaf(path.nodes[0]), path.slots[0],
+                           struct btrfs_inode_map_item);
+       btrfs_disk_key_to_cpu(&stat_data_key, &map->key);
+       ret = btrfs_del_item(trans, root->fs_info->inode_root, &path);
+       BUG_ON(ret);
+       btrfs_release_path(root, &path);
+       btrfs_init_path(&path);
+
+       ret = btrfs_lookup_inode(trans, root, &path, objectid, -1);
+       BUG_ON(ret);
+       ret = btrfs_del_item(trans, root, &path);
+       BUG_ON(ret);
+       btrfs_release_path(root, &path);
+error:
+       return ret;
+}
+
+static void btrfs_delete_inode(struct inode *inode)
+{
+       struct btrfs_trans_handle *trans;
+       struct btrfs_root *root = btrfs_sb(inode->i_sb);
+       truncate_inode_pages(&inode->i_data, 0);
+       if (is_bad_inode(inode)) {
+               goto no_delete;
+       }
+       inode->i_size = 0;
+       if (inode->i_blocks)
+               WARN_ON(1);
+
+       mutex_lock(&root->fs_info->fs_mutex);
+       trans = btrfs_start_transaction(root, 1);
+       btrfs_free_inode(trans, root, inode);
+       btrfs_end_transaction(trans, root);
+       mutex_unlock(&root->fs_info->fs_mutex);
+       return;
+no_delete:
+       clear_inode(inode);
+}
+
+
 static int btrfs_inode_by_name(struct inode *dir, struct dentry *dentry,
                              ino_t *ino)
 {
@@ -272,6 +370,13 @@ static int btrfs_readdir(struct file *filp, void *dirent, filldir_t filldir)
                                leaf = btrfs_buffer_leaf(path.nodes[0]);
                                nritems = btrfs_header_nritems(&leaf->header);
                                slot = path.slots[0];
+#if 0
+                               page_cache_readahead(
+                                    inode->i_sb->s_bdev->bd_inode->i_mapping,
+                                    &filp->f_ra, filp,
+                                    path.nodes[0]->b_blocknr >>
+                                    (PAGE_CACHE_SHIFT - inode->i_blkbits), 1);
+#endif
                        } else {
                                slot++;
                                path.slots[0]++;
@@ -441,8 +546,6 @@ static int btrfs_add_nondir(struct btrfs_trans_handle *trans,
                d_instantiate(dentry, inode);
                return 0;
        }
-       inode_dec_link_count(inode);
-       iput(inode);
        return err;
 }
 
@@ -453,6 +556,7 @@ static int btrfs_create(struct inode *dir, struct dentry *dentry,
        struct btrfs_root *root = btrfs_sb(dir->i_sb);
        struct inode *inode;
        int err;
+       int drop_inode = 0;
 
        mutex_lock(&root->fs_info->fs_mutex);
        trans = btrfs_start_transaction(root, 1);
@@ -462,10 +566,16 @@ static int btrfs_create(struct inode *dir, struct dentry *dentry,
                goto out_unlock;
        // FIXME mark the inode dirty
        err = btrfs_add_nondir(trans, dentry, inode);
+       if (err)
+               drop_inode = 1;
        dir->i_sb->s_dirt = 1;
        btrfs_end_transaction(trans, root);
 out_unlock:
        mutex_unlock(&root->fs_info->fs_mutex);
+       if (drop_inode) {
+               inode_dec_link_count(inode);
+               iput(inode);
+       }
        return err;
 }
 
@@ -516,7 +626,7 @@ static struct file_system_type btrfs_fs_type = {
 
 static struct super_operations btrfs_super_ops = {
        .statfs         = simple_statfs,
-       .drop_inode     = generic_delete_inode,
+       .delete_inode   = btrfs_delete_inode,
        .put_super      = btrfs_put_super,
        .read_inode     = btrfs_read_locked_inode,
        .write_super    = btrfs_write_super,
@@ -526,6 +636,7 @@ static struct super_operations btrfs_super_ops = {
 static struct inode_operations btrfs_dir_inode_operations = {
        .lookup         = btrfs_lookup,
        .create         = btrfs_create,
+       .unlink         = btrfs_unlink,
 };
 
 static struct file_operations btrfs_dir_file_operations = {