1 files changed, 48 insertions, 12 deletions

diff --git a/fs/btrfs/inode.c b/fs/btrfs/inode.c
index 1af1ea88e8a8..f2fb974ed8f0 100644
--- a/fs/btrfs/inode.c
+++ b/fs/btrfs/inode.c
@@ -764,6 +764,7 @@ static noinline int cow_file_range(struct inode *inode,
         struct extent_map_tree *em_tree = &BTRFS_I(inode)->extent_tree;
         int ret = 0;
 
+        BUG_ON(root == root->fs_info->tree_root);
         trans = btrfs_join_transaction(root, 1);
         BUG_ON(!trans);
         btrfs_set_trans_block_group(trans, inode);
@@ -1035,10 +1036,16 @@ static noinline int run_delalloc_nocow(struct inode *inode,
         int type;
         int nocow;
         int check_prev = 1;
+        bool nolock = false;
 
         path = btrfs_alloc_path();
         BUG_ON(!path);
-        trans = btrfs_join_transaction(root, 1);
+        if (root == root->fs_info->tree_root) {
+                nolock = true;
+                trans = btrfs_join_transaction_nolock(root, 1);
+        } else {
+                trans = btrfs_join_transaction(root, 1);
+        }
         BUG_ON(!trans);
 
         cow_start = (u64)-1;
@@ -1211,8 +1218,13 @@ out_check:
                 BUG_ON(ret);
         }
 
-        ret = btrfs_end_transaction(trans, root);
-        BUG_ON(ret);
+        if (nolock) {
+                ret = btrfs_end_transaction_nolock(trans, root);
+                BUG_ON(ret);
+        } else {
+                ret = btrfs_end_transaction(trans, root);
+                BUG_ON(ret);
+        }
         btrfs_free_path(path);
         return 0;
 }
@@ -1289,6 +1301,8 @@ static int btrfs_set_bit_hook(struct inode *inode,
         if (!(state->state & EXTENT_DELALLOC) && (*bits & EXTENT_DELALLOC)) {
                 struct btrfs_root *root = BTRFS_I(inode)->root;
                 u64 len = state->end + 1 - state->start;
+                int do_list = (root->root_key.objectid !=
+                               BTRFS_ROOT_TREE_OBJECTID);
 
                 if (*bits & EXTENT_FIRST_DELALLOC)
                         *bits &= ~EXTENT_FIRST_DELALLOC;
@@ -1298,7 +1312,7 @@ static int btrfs_set_bit_hook(struct inode *inode,
                 spin_lock(&root->fs_info->delalloc_lock);
                 BTRFS_I(inode)->delalloc_bytes += len;
                 root->fs_info->delalloc_bytes += len;
-                if (list_empty(&BTRFS_I(inode)->delalloc_inodes)) {
+                if (do_list && list_empty(&BTRFS_I(inode)->delalloc_inodes)) {
                         list_add_tail(&BTRFS_I(inode)->delalloc_inodes,
                                       &root->fs_info->delalloc_inodes);
                 }
@@ -1321,6 +1335,8 @@ static int btrfs_clear_bit_hook(struct inode *inode,
         if ((state->state & EXTENT_DELALLOC) && (*bits & EXTENT_DELALLOC)) {
                 struct btrfs_root *root = BTRFS_I(inode)->root;
                 u64 len = state->end + 1 - state->start;
+                int do_list = (root->root_key.objectid !=
+                               BTRFS_ROOT_TREE_OBJECTID);
 
                 if (*bits & EXTENT_FIRST_DELALLOC)
                         *bits &= ~EXTENT_FIRST_DELALLOC;
@@ -1330,14 +1346,15 @@ static int btrfs_clear_bit_hook(struct inode *inode,
                 if (*bits & EXTENT_DO_ACCOUNTING)
                         btrfs_delalloc_release_metadata(inode, len);
 
-                if (root->root_key.objectid != BTRFS_DATA_RELOC_TREE_OBJECTID)
+                if (root->root_key.objectid != BTRFS_DATA_RELOC_TREE_OBJECTID
+                    && do_list)
                         btrfs_free_reserved_data_space(inode, len);
 
                 spin_lock(&root->fs_info->delalloc_lock);
                 root->fs_info->delalloc_bytes -= len;
                 BTRFS_I(inode)->delalloc_bytes -= len;
 
-                if (BTRFS_I(inode)->delalloc_bytes == 0 &&
+                if (do_list && BTRFS_I(inode)->delalloc_bytes == 0 &&
                     !list_empty(&BTRFS_I(inode)->delalloc_inodes)) {
                         list_del_init(&BTRFS_I(inode)->delalloc_inodes);
                 }
@@ -1426,7 +1443,10 @@ static int btrfs_submit_bio_hook(struct inode *inode, int rw, struct bio *bio,
 
         skip_sum = BTRFS_I(inode)->flags & BTRFS_INODE_NODATASUM;
 
-        ret = btrfs_bio_wq_end_io(root->fs_info, bio, 0);
+        if (root == root->fs_info->tree_root)
+                ret = btrfs_bio_wq_end_io(root->fs_info, bio, 2);
+        else
+                ret = btrfs_bio_wq_end_io(root->fs_info, bio, 0);
         BUG_ON(ret);
 
         if (!(rw & REQ_WRITE)) {
@@ -1662,6 +1682,7 @@ static int btrfs_finish_ordered_io(struct inode *inode, u64 start, u64 end)
         struct extent_state *cached_state = NULL;
         int compressed = 0;
         int ret;
+        bool nolock = false;
 
         ret = btrfs_dec_test_ordered_pending(inode, &ordered_extent, start,
                                              end - start + 1);
@@ -1669,11 +1690,17 @@ static int btrfs_finish_ordered_io(struct inode *inode, u64 start, u64 end)
                 return 0;
         BUG_ON(!ordered_extent);
 
+        nolock = (root == root->fs_info->tree_root);
+
         if (test_bit(BTRFS_ORDERED_NOCOW, &ordered_extent->flags)) {
                 BUG_ON(!list_empty(&ordered_extent->list));
                 ret = btrfs_ordered_update_i_size(inode, 0, ordered_extent);
                 if (!ret) {
-                        trans = btrfs_join_transaction(root, 1);
+                        if (nolock)
+                                trans = btrfs_join_transaction_nolock(root, 1);
+                        else
+                                trans = btrfs_join_transaction(root, 1);
+                        BUG_ON(!trans);
                         btrfs_set_trans_block_group(trans, inode);
                         trans->block_rsv = &root->fs_info->delalloc_block_rsv;
                         ret = btrfs_update_inode(trans, root, inode);
@@ -1686,7 +1713,10 @@ static int btrfs_finish_ordered_io(struct inode *inode, u64 start, u64 end)
                          ordered_extent->file_offset + ordered_extent->len - 1,
                          0, &cached_state, GFP_NOFS);
 
-        trans = btrfs_join_transaction(root, 1);
+        if (nolock)
+                trans = btrfs_join_transaction_nolock(root, 1);
+        else
+                trans = btrfs_join_transaction(root, 1);
         btrfs_set_trans_block_group(trans, inode);
         trans->block_rsv = &root->fs_info->delalloc_block_rsv;
 
@@ -1725,9 +1755,15 @@ static int btrfs_finish_ordered_io(struct inode *inode, u64 start, u64 end)
         ret = btrfs_update_inode(trans, root, inode);
         BUG_ON(ret);
 out:
-        btrfs_delalloc_release_metadata(inode, ordered_extent->len);
-        if (trans)
-                btrfs_end_transaction(trans, root);
+        if (nolock) {
+                if (trans)
+                        btrfs_end_transaction_nolock(trans, root);
+        } else {
+                btrfs_delalloc_release_metadata(inode, ordered_extent->len);
+                if (trans)
+                        btrfs_end_transaction(trans, root);
+        }
+
         /* once for us */
         btrfs_put_ordered_extent(ordered_extent);
         /* once for the tree */