cifs: ensure that we always do cifsFileInfo_get under the spinlock
The readpages bug is a regression that was introduced in 6993f74a5.
This also fixes a couple of similar bugs in the uncached read and write
codepaths.
Also, prevent this sort of thing in the future by having cifsFileInfo_get
take the spinlock itself, and adding a _locked variant for use in places
that are already holding the lock. The _put code has always done that
so this makes for a less confusing interface.
Cc: <stable@vger.kernel.org> # 3.5.x
Reviewed-by: Pavel Shilovsky <pshilovsky@samba.org>
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Steve French <smfrench@gmail.com>
diff --git a/fs/cifs/cifsglob.h b/fs/cifs/cifsglob.h
index bcdf4d4..497da5c 100644
--- a/fs/cifs/cifsglob.h
+++ b/fs/cifs/cifsglob.h
@@ -765,13 +765,13 @@
* Take a reference on the file private data. Must be called with
* cifs_file_list_lock held.
*/
-static inline
-struct cifsFileInfo *cifsFileInfo_get(struct cifsFileInfo *cifs_file)
+static inline void
+cifsFileInfo_get_locked(struct cifsFileInfo *cifs_file)
{
++cifs_file->count;
- return cifs_file;
}
+struct cifsFileInfo *cifsFileInfo_get(struct cifsFileInfo *cifs_file);
void cifsFileInfo_put(struct cifsFileInfo *cifs_file);
/*