From fae994276f87f9222d4d95c446298e2514fc2666 Mon Sep 17 00:00:00 2001
From: Josef Bacik <josef@redhat.com>
Date: Wed, 13 Apr 2011 15:15:59 -0400
Subject: [PATCH] --- yaml --- r: 253078 b: refs/heads/master c:
 2a1eb4614d984d5cd4c928784e9afcf5c07f93be h: refs/heads/master v: v3

---
 [refs]                       |  2 +-
 trunk/fs/btrfs/transaction.c | 17 +++++++++++++++++
 trunk/fs/btrfs/transaction.h |  2 ++
 3 files changed, 20 insertions(+), 1 deletion(-)

diff --git a/[refs] b/[refs]
index e2ce3a833bdb..5aa5fd1373d1 100644
--- a/[refs]
+++ b/[refs]
@@ -1,2 +1,2 @@
 ---
-refs/heads/master: 7a7eaa40a39bde4eefc91aadeb1ce3dc4e6a1252
+refs/heads/master: 2a1eb4614d984d5cd4c928784e9afcf5c07f93be
diff --git a/trunk/fs/btrfs/transaction.c b/trunk/fs/btrfs/transaction.c
index 70bfb26df967..46f40564c168 100644
--- a/trunk/fs/btrfs/transaction.c
+++ b/trunk/fs/btrfs/transaction.c
@@ -184,6 +184,15 @@ static struct btrfs_trans_handle *start_transaction(struct btrfs_root *root,
 
 	if (root->fs_info->fs_state & BTRFS_SUPER_FLAG_ERROR)
 		return ERR_PTR(-EROFS);
+
+	if (current->journal_info) {
+		WARN_ON(type != TRANS_JOIN && type != TRANS_JOIN_NOLOCK);
+		h = current->journal_info;
+		h->use_count++;
+		h->orig_rsv = h->block_rsv;
+		h->block_rsv = NULL;
+		goto got_it;
+	}
 again:
 	h = kmem_cache_alloc(btrfs_trans_handle_cachep, GFP_NOFS);
 	if (!h)
@@ -213,7 +222,9 @@ static struct btrfs_trans_handle *start_transaction(struct btrfs_root *root,
 	h->block_group = 0;
 	h->bytes_reserved = 0;
 	h->delayed_ref_updates = 0;
+	h->use_count = 1;
 	h->block_rsv = NULL;
+	h->orig_rsv = NULL;
 
 	smp_mb();
 	if (cur_trans->blocked && may_wait_transaction(root, type)) {
@@ -241,6 +252,7 @@ static struct btrfs_trans_handle *start_transaction(struct btrfs_root *root,
 		}
 	}
 
+got_it:
 	if (type != TRANS_JOIN_NOLOCK)
 		mutex_lock(&root->fs_info->trans_mutex);
 	record_root_in_trans(h, root);
@@ -428,6 +440,11 @@ static int __btrfs_end_transaction(struct btrfs_trans_handle *trans,
 	struct btrfs_fs_info *info = root->fs_info;
 	int count = 0;
 
+	if (--trans->use_count) {
+		trans->block_rsv = trans->orig_rsv;
+		return 0;
+	}
+
 	while (count < 4) {
 		unsigned long cur = trans->delayed_ref_updates;
 		trans->delayed_ref_updates = 0;
diff --git a/trunk/fs/btrfs/transaction.h b/trunk/fs/btrfs/transaction.h
index 1f573f09dba2..154314f80f8d 100644
--- a/trunk/fs/btrfs/transaction.h
+++ b/trunk/fs/btrfs/transaction.h
@@ -47,11 +47,13 @@ struct btrfs_trans_handle {
 	u64 transid;
 	u64 block_group;
 	u64 bytes_reserved;
+	unsigned long use_count;
 	unsigned long blocks_reserved;
 	unsigned long blocks_used;
 	unsigned long delayed_ref_updates;
 	struct btrfs_transaction *transaction;
 	struct btrfs_block_rsv *block_rsv;
+	struct btrfs_block_rsv *orig_rsv;
 };
 
 struct btrfs_pending_snapshot {