Btrfs: Avoid orphan inodes cleanup during committing transaction

btrfs_lookup_dentry may trigger orphan cleanup, so it's not good
to call it while committing a transaction.

Signed-off-by: Yan Zheng <zheng.yan@oracle.com>
Signed-off-by: Chris Mason <chris.mason@oracle.com>

diff --git a/fs/btrfs/ioctl.c b/fs/btrfs/ioctl.c
index a1a8db8..3d6b338 100644 (file)
--- a/fs/btrfs/ioctl.c
+++ b/fs/btrfs/ioctl.c
@@ -237,7 +237,6 @@ static noinline int create_subvol(struct btrfs_root *root,
        u64 objectid;
        u64 new_dirid = BTRFS_FIRST_FREE_OBJECTID;
        u64 index = 0;
-       unsigned long nr = 1;
 
        /*
         * 1 - inode item
@@ -342,24 +341,21 @@ static noinline int create_subvol(struct btrfs_root *root,
 
        d_instantiate(dentry, btrfs_lookup_dentry(dir, dentry));
 fail:
-       nr = trans->blocks_used;
        err = btrfs_commit_transaction(trans, root);
        if (err && !ret)
                ret = err;
 
        btrfs_unreserve_metadata_space(root, 6);
-       btrfs_btree_balance_dirty(root, nr);
        return ret;
 }
 
 static int create_snapshot(struct btrfs_root *root, struct dentry *dentry,
                           char *name, int namelen)
 {
+       struct inode *inode;
        struct btrfs_pending_snapshot *pending_snapshot;
        struct btrfs_trans_handle *trans;
-       int ret = 0;
-       int err;
-       unsigned long nr = 0;
+       int ret;
 
        if (!root->ref_cows)
                return -EINVAL;
@@ -372,20 +368,20 @@ static int create_snapshot(struct btrfs_root *root, struct dentry *dentry,
         */
        ret = btrfs_reserve_metadata_space(root, 6);
        if (ret)
-               goto fail_unlock;
+               goto fail;
 
        pending_snapshot = kzalloc(sizeof(*pending_snapshot), GFP_NOFS);
        if (!pending_snapshot) {
                ret = -ENOMEM;
                btrfs_unreserve_metadata_space(root, 6);
-               goto fail_unlock;
+               goto fail;
        }
        pending_snapshot->name = kmalloc(namelen + 1, GFP_NOFS);
        if (!pending_snapshot->name) {
                ret = -ENOMEM;
                kfree(pending_snapshot);
                btrfs_unreserve_metadata_space(root, 6);
-               goto fail_unlock;
+               goto fail;
        }
        memcpy(pending_snapshot->name, name, namelen);
        pending_snapshot->name[namelen] = '\0';
@@ -395,10 +391,19 @@ static int create_snapshot(struct btrfs_root *root, struct dentry *dentry,
        pending_snapshot->root = root;
        list_add(&pending_snapshot->list,
                 &trans->transaction->pending_snapshots);
-       err = btrfs_commit_transaction(trans, root);
+       ret = btrfs_commit_transaction(trans, root);
+       BUG_ON(ret);
+       btrfs_unreserve_metadata_space(root, 6);
 
-fail_unlock:
-       btrfs_btree_balance_dirty(root, nr);
+       inode = btrfs_lookup_dentry(dentry->d_parent->d_inode, dentry);
+       if (IS_ERR(inode)) {
+               ret = PTR_ERR(inode);
+               goto fail;
+       }
+       BUG_ON(!inode);
+       d_instantiate(dentry, inode);
+       ret = 0;
+fail:
        return ret;
 }
 

diff --git a/fs/btrfs/transaction.c b/fs/btrfs/transaction.c
index b7b22c3..728e8fe 100644 (file)
--- a/fs/btrfs/transaction.c
+++ b/fs/btrfs/transaction.c
@@ -796,7 +796,6 @@ static noinline int create_pending_snapshot(struct btrfs_trans_handle *trans,
        memcpy(&pending->root_key, &key, sizeof(key));
 fail:
        kfree(new_root_item);
-       btrfs_unreserve_metadata_space(root, 6);
        return ret;
 }
 
@@ -808,7 +807,6 @@ static noinline int finish_pending_snapshot(struct btrfs_fs_info *fs_info,
        u64 index = 0;
        struct btrfs_trans_handle *trans;
        struct inode *parent_inode;
-       struct inode *inode;
        struct btrfs_root *parent_root;
 
        parent_inode = pending->dentry->d_parent->d_inode;
@@ -840,8 +838,6 @@ static noinline int finish_pending_snapshot(struct btrfs_fs_info *fs_info,
 
        BUG_ON(ret);
 
-       inode = btrfs_lookup_dentry(parent_inode, pending->dentry);
-       d_instantiate(pending->dentry, inode);
 fail:
        btrfs_end_transaction(trans, fs_info->fs_root);
        return ret;