1 files changed, 17 insertions, 19 deletions

diff --git a/fs/btrfs/transaction.c b/fs/btrfs/transaction.c
index 51dcec86757f..654755b18951 100644
--- a/fs/btrfs/transaction.c
+++ b/fs/btrfs/transaction.c
@@ -260,7 +260,7 @@ static struct btrfs_trans_handle *start_transaction(struct btrfs_root *root,
 {
         struct btrfs_trans_handle *h;
         struct btrfs_transaction *cur_trans;
-        int retries = 0;
+        u64 num_bytes = 0;
         int ret;
 
         if (root->fs_info->fs_state & BTRFS_SUPER_FLAG_ERROR)
@@ -274,6 +274,19 @@ static struct btrfs_trans_handle *start_transaction(struct btrfs_root *root,
                 h->block_rsv = NULL;
                 goto got_it;
         }
+
+        /*
+         * Do the reservation before we join the transaction so we can do all
+         * the appropriate flushing if need be.
+         */
+        if (num_items > 0 && root != root->fs_info->chunk_root) {
+                num_bytes = btrfs_calc_trans_metadata_size(root, num_items);
+                ret = btrfs_block_rsv_add(NULL, root,
+                                          &root->fs_info->trans_block_rsv,
+                                          num_bytes);
+                if (ret)
+                        return ERR_PTR(ret);
+        }
 again:
         h = kmem_cache_alloc(btrfs_trans_handle_cachep, GFP_NOFS);
         if (!h)
@@ -310,24 +323,9 @@ again:
                 goto again;
         }
 
-        if (num_items > 0) {
-                ret = btrfs_trans_reserve_metadata(h, root, num_items);
-                if (ret == -EAGAIN && !retries) {
-                        retries++;
-                        btrfs_commit_transaction(h, root);
-                        goto again;
-                } else if (ret == -EAGAIN) {
-                        /*
-                         * We have already retried and got EAGAIN, so really we
-                         * don't have space, so set ret to -ENOSPC.
-                         */
-                        ret = -ENOSPC;
-                }
-
-                if (ret < 0) {
-                        btrfs_end_transaction(h, root);
-                        return ERR_PTR(ret);
-                }
+        if (num_bytes) {
+                h->block_rsv = &root->fs_info->trans_block_rsv;
+                h->bytes_reserved = num_bytes;
         }
 
 got_it: