Btrfs: add helper btrfs_fdatawrite_range

To avoid duplicating this double filemap_fdatawrite_range() call for
inodes with async extents (compressed writes) so often.

Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Chris Mason <clm@fb.com>

1 files changed, 2 insertions, 22 deletions

diff --git a/fs/btrfs/ordered-data.c b/fs/btrfs/ordered-data.c
index ac734ec4cc20..1401b1af4f06 100644
--- a/fs/btrfs/ordered-data.c
+++ b/fs/btrfs/ordered-data.c
@@ -725,30 +725,10 @@ int btrfs_wait_ordered_range(struct inode *inode, u64 start, u64 len)
         /* start IO across the range first to instantiate any delalloc
          * extents
          */
-        ret = filemap_fdatawrite_range(inode->i_mapping, start, orig_end);
+        ret = btrfs_fdatawrite_range(inode, start, orig_end);
         if (ret)
                 return ret;
-        /*
-         * So with compression we will find and lock a dirty page and clear the
-         * first one as dirty, setup an async extent, and immediately return
-         * with the entire range locked but with nobody actually marked with
-         * writeback.  So we can't just filemap_write_and_wait_range() and
-         * expect it to work since it will just kick off a thread to do the
-         * actual work.  So we need to call filemap_fdatawrite_range _again_
-         * since it will wait on the page lock, which won't be unlocked until
-         * after the pages have been marked as writeback and so we're good to go
-         * from there.  We have to do this otherwise we'll miss the ordered
-         * extents and that results in badness.  Please Josef, do not think you
-         * know better and pull this out at some point in the future, it is
-         * right and you are wrong.
-         */
-        if (test_bit(BTRFS_INODE_HAS_ASYNC_EXTENT,
-                     &BTRFS_I(inode)->runtime_flags)) {
-                ret = filemap_fdatawrite_range(inode->i_mapping, start,
-                                               orig_end);
-                if (ret)
-                        return ret;
-        }
+
         ret = filemap_fdatawait_range(inode->i_mapping, start, orig_end);
         if (ret)
                 return ret;