ceph: Don't use ceph-sync-mode for synchronous-fs.

Sending reads and writes through the sync read/write paths bypasses the
page cache, which is not expected or generally a good idea.  Removing
the write check is safe as there is a conditional vfs_fsync_range() later
in ceph_aio_write that already checks for the same flag (via
IS_SYNC(inode)).

Signed-off-by: Jianpeng Ma <majianpeng@gmail.com>
Reviewed-by: Sage Weil <sage@inktank.com>

1 files changed, 0 insertions, 2 deletions

diff --git a/fs/ceph/file.c b/fs/ceph/file.c
index 7d4e769f1d3d..63ec830b9306 100644
--- a/fs/ceph/file.c
+++ b/fs/ceph/file.c
@@ -659,7 +659,6 @@ again:
 
         if ((got & (CEPH_CAP_FILE_CACHE|CEPH_CAP_FILE_LAZYIO)) == 0 ||
             (iocb->ki_filp->f_flags & O_DIRECT) ||
-            (inode->i_sb->s_flags & MS_SYNCHRONOUS) ||
             (fi->flags & CEPH_F_SYNC))
                 /* hmm, this isn't really async... */
                 ret = ceph_sync_read(filp, base, len, ppos, &checkeof);
@@ -763,7 +762,6 @@ retry_snap:
 
         if ((got & (CEPH_CAP_FILE_BUFFER|CEPH_CAP_FILE_LAZYIO)) == 0 ||
             (iocb->ki_filp->f_flags & O_DIRECT) ||
-            (inode->i_sb->s_flags & MS_SYNCHRONOUS) ||
             (fi->flags & CEPH_F_SYNC)) {
                 mutex_unlock(&inode->i_mutex);
                 written = ceph_sync_write(file, iov->iov_base, count,