quota: Introduce DQUOT_QUOTA_SYS_FILE flag

If filesystem can handle quota files as system files hidden from users, we can
skip a lot of cache invalidation, syncing, inode flags setting etc. when
turning quotas on, off and quota_sync. Allow filesystem to indicate that it is
hiding quota files from users by DQUOT_QUOTA_SYS_FILE flag.

Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Mark Fasheh <mfasheh@suse.com>

1 files changed, 7 insertions, 0 deletions

diff --git a/include/linux/quota.h b/include/linux/quota.h
index 93717abcd35b..80b8807b4988 100644
--- a/include/linux/quota.h
+++ b/include/linux/quota.h
@@ -332,6 +332,13 @@ enum {
 #define DQUOT_SUSPENDED         (1 << _DQUOT_SUSPENDED)
 #define DQUOT_STATE_FLAGS       (DQUOT_USAGE_ENABLED | DQUOT_LIMITS_ENABLED | \
                                  DQUOT_SUSPENDED)
+/* Other quota flags */
+#define DQUOT_QUOTA_SYS_FILE    (1 << 6)        /* Quota file is a special
+                                                 * system file and user cannot
+                                                 * touch it. Filesystem is
+                                                 * responsible for setting
+                                                 * S_NOQUOTA, S_NOATIME flags
+                                                 */
 
 static inline unsigned int dquot_state_flag(unsigned int flags, int type)
 {