---

yaml --- r: 360460 b: refs/heads/master c: d4edf39 h: refs/heads/master v: v3
git-mirror · Feb 20, 2013 · 23b4194 · 23b4194
1 parent 899cf57
commit 23b4194
Show file tree

Hide file tree

Showing 5 changed files with 38 additions and 4 deletions.
diff --git a/[refs] b/[refs]
@@ -1,2 +1,2 @@
 ---
-refs/heads/master: 178260b2c14969f29ba39a78df74ed485abc6203
+refs/heads/master: d4edf39bd5db443151efc993dac67ec9d6b5b8c1
diff --git a/trunk/fs/btrfs/ioctl.c b/trunk/fs/btrfs/ioctl.c
@@ -3114,7 +3114,7 @@ static noinline long btrfs_ioctl_start_sync(struct btrfs_root *root,
 	u64 transid;
 	int ret;
 
-	trans = btrfs_attach_transaction(root);
+	trans = btrfs_attach_transaction_barrier(root);
 	if (IS_ERR(trans)) {
 		if (PTR_ERR(trans) != -ENOENT)
 			return PTR_ERR(trans);

diff --git a/trunk/fs/btrfs/super.c b/trunk/fs/btrfs/super.c
@@ -878,7 +878,7 @@ int btrfs_sync_fs(struct super_block *sb, int wait)
 
 	btrfs_wait_ordered_extents(root, 0);
 
-	trans = btrfs_attach_transaction(root);
+	trans = btrfs_attach_transaction_barrier(root);
 	if (IS_ERR(trans)) {
 		/* no transaction, don't bother */
 		if (PTR_ERR(trans) == -ENOENT)
@@ -1563,7 +1563,7 @@ static int btrfs_freeze(struct super_block *sb)
 	struct btrfs_trans_handle *trans;
 	struct btrfs_root *root = btrfs_sb(sb)->tree_root;
 
-	trans = btrfs_attach_transaction(root);
+	trans = btrfs_attach_transaction_barrier(root);
 	if (IS_ERR(trans)) {
 		/* no transaction, don't bother */
 		if (PTR_ERR(trans) == -ENOENT)

diff --git a/trunk/fs/btrfs/transaction.c b/trunk/fs/btrfs/transaction.c
@@ -469,11 +469,43 @@ struct btrfs_trans_handle *btrfs_start_ioctl_transaction(struct btrfs_root *root
 	return start_transaction(root, 0, TRANS_USERSPACE, 0);
 }
 
+/*
+ * btrfs_attach_transaction() - catch the running transaction
+ *
+ * It is used when we want to commit the current the transaction, but
+ * don't want to start a new one.
+ *
+ * Note: If this function return -ENOENT, it just means there is no
+ * running transaction. But it is possible that the inactive transaction
+ * is still in the memory, not fully on disk. If you hope there is no
+ * inactive transaction in the fs when -ENOENT is returned, you should
+ * invoke
+ *     btrfs_attach_transaction_barrier()
+ */
 struct btrfs_trans_handle *btrfs_attach_transaction(struct btrfs_root *root)
 {
 	return start_transaction(root, 0, TRANS_ATTACH, 0);
 }
 
+/*
+ * btrfs_attach_transaction() - catch the running transaction
+ *
+ * It is similar to the above function, the differentia is this one
+ * will wait for all the inactive transactions until they fully
+ * complete.
+ */
+struct btrfs_trans_handle *
+btrfs_attach_transaction_barrier(struct btrfs_root *root)
+{
+	struct btrfs_trans_handle *trans;
+
+	trans = start_transaction(root, 0, TRANS_ATTACH, 0);
+	if (IS_ERR(trans) && PTR_ERR(trans) == -ENOENT)
+		btrfs_wait_for_commit(root, 0);
+
+	return trans;
+}
+
 /* wait for a transaction commit to be fully complete */
 static noinline void wait_for_commit(struct btrfs_root *root,
 				    struct btrfs_transaction *commit)

diff --git a/trunk/fs/btrfs/transaction.h b/trunk/fs/btrfs/transaction.h
@@ -112,6 +112,8 @@ struct btrfs_trans_handle *btrfs_start_transaction_lflush(
 struct btrfs_trans_handle *btrfs_join_transaction(struct btrfs_root *root);
 struct btrfs_trans_handle *btrfs_join_transaction_nolock(struct btrfs_root *root);
 struct btrfs_trans_handle *btrfs_attach_transaction(struct btrfs_root *root);
+struct btrfs_trans_handle *btrfs_attach_transaction_barrier(
+					struct btrfs_root *root);
 struct btrfs_trans_handle *btrfs_start_ioctl_transaction(struct btrfs_root *root);
 int btrfs_wait_for_commit(struct btrfs_root *root, u64 transid);
 int btrfs_write_and_wait_transaction(struct btrfs_trans_handle *trans,