Btrfs: fill ->last_trans for delayed inode in btrfs_fill_inode.

We need to fill inode when we found a node for it in delayed_nodes_tree.
But we did not fill the ->last_trans currently, it will cause the test
of xfstest/generic/311 fail. Scenario of the 311 is shown as below:

Problem:
	(1). test_fd = open(fname, O_RDWR|O_DIRECT)
	(2). pwrite(test_fd, buf, 4096, 0)
	(3). close(test_fd)
	(4). drop_all_caches()	<-------- "echo 3 > /proc/sys/vm/drop_caches"
	(5). test_fd = open(fname, O_RDWR|O_DIRECT)
	(6). fsync(test_fd);
				<-------- we did not get the correct log entry for the file
Reason:
	When we re-open this file in (5), we would find a node
in delayed_nodes_tree and fill the inode we are lookup with the
information. But the ->last_trans is not filled, then the fsync()
will check the ->last_trans and found it's 0 then say this inode
is already in our tree which is commited, not recording the extents
for it.

Fix:
	This patch fill the ->last_trans properly and set the
runtime_flags if needed in this situation. Then we can get the
log entries we expected after (6) and generic/311 passed.

Signed-off-by: Dongsheng Yang <yangds.fnst@cn.fujitsu.com>
Reviewed-by: Miao Xie <miaoxie@huawei.com>
Signed-off-by: Chris Mason <clm@fb.com>

diff --git a/fs/btrfs/delayed-inode.c b/fs/btrfs/delayed-inode.c
index cde698a..a2ae427 100644 (file)
--- a/fs/btrfs/delayed-inode.c
+++ b/fs/btrfs/delayed-inode.c
@@ -1802,6 +1802,8 @@ int btrfs_fill_inode(struct inode *inode, u32 *rdev)
        set_nlink(inode, btrfs_stack_inode_nlink(inode_item));
        inode_set_bytes(inode, btrfs_stack_inode_nbytes(inode_item));
        BTRFS_I(inode)->generation = btrfs_stack_inode_generation(inode_item);
+        BTRFS_I(inode)->last_trans = btrfs_stack_inode_transid(inode_item);
+
        inode->i_version = btrfs_stack_inode_sequence(inode_item);
        inode->i_rdev = 0;
        *rdev = btrfs_stack_inode_rdev(inode_item);

diff --git a/fs/btrfs/inode.c b/fs/btrfs/inode.c
index 27b59b8..0020b56 100644 (file)
--- a/fs/btrfs/inode.c
+++ b/fs/btrfs/inode.c
@@ -3633,25 +3633,28 @@ static void btrfs_read_locked_inode(struct inode *inode)
        BTRFS_I(inode)->generation = btrfs_inode_generation(leaf, inode_item);
        BTRFS_I(inode)->last_trans = btrfs_inode_transid(leaf, inode_item);
 
+       inode->i_version = btrfs_inode_sequence(leaf, inode_item);
+       inode->i_generation = BTRFS_I(inode)->generation;
+       inode->i_rdev = 0;
+       rdev = btrfs_inode_rdev(leaf, inode_item);
+
+       BTRFS_I(inode)->index_cnt = (u64)-1;
+       BTRFS_I(inode)->flags = btrfs_inode_flags(leaf, inode_item);
+
+cache_index:
        /*
         * If we were modified in the current generation and evicted from memory
         * and then re-read we need to do a full sync since we don't have any
         * idea about which extents were modified before we were evicted from
         * cache.
+        *
+        * This is required for both inode re-read from disk and delayed inode
+        * in delayed_nodes_tree.
         */
        if (BTRFS_I(inode)->last_trans == root->fs_info->generation)
                set_bit(BTRFS_INODE_NEEDS_FULL_SYNC,
                        &BTRFS_I(inode)->runtime_flags);
 
-       inode->i_version = btrfs_inode_sequence(leaf, inode_item);
-       inode->i_generation = BTRFS_I(inode)->generation;
-       inode->i_rdev = 0;
-       rdev = btrfs_inode_rdev(leaf, inode_item);
-
-       BTRFS_I(inode)->index_cnt = (u64)-1;
-       BTRFS_I(inode)->flags = btrfs_inode_flags(leaf, inode_item);
-
-cache_index:
        path->slots[0]++;
        if (inode->i_nlink != 1 ||
            path->slots[0] >= btrfs_header_nritems(leaf))