[GFS2] Alter direct I/O path

As per comments received, alter the GFS2 direct I/O path so that
it uses the standard read functions "out of the box". Needs a
small change to one of the VFS functions. This reduces the size
of the code quite a lot and also removes the need for one new export.

Some more work remains to be done, but this is the bones of the
thing.

Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>

1 files changed, 2 insertions, 2 deletions

diff --git a/mm/filemap.c b/mm/filemap.c
index b9c91ab7f0f8..a92d690b3ae5 100644
--- a/mm/filemap.c
+++ b/mm/filemap.c
@@ -1122,7 +1122,6 @@ success:
         desc->arg.buf += size;
         return size;
 }
-EXPORT_SYMBOL_GPL(file_read_actor);
 
 /**
  * __generic_file_aio_read - generic filesystem read routine
@@ -1184,7 +1183,8 @@ __generic_file_aio_read(struct kiocb *iocb, const struct iovec *iov,
                                 *ppos = pos + retval;
                 }
                 file_accessed(filp);
-                goto out;
+                if (retval != 0)
+                        goto out;
         }
 
         retval = 0;