quota: Allow disabling tracking of dirty dquots in a list

Filesystems that are journalling quotas generally don't need tracking of
dirty dquots in a list since forcing a transaction commit flushes all
quotas anyway. Allow filesystem to say it doesn't want dquots to be
tracked as it reduces contention on the dq_list_lock.

Signed-off-by: Jan Kara <jack@suse.cz>

1 files changed, 3 insertions, 0 deletions

diff --git a/include/linux/quota.h b/include/linux/quota.h
index ad6809f099ac..eccc1cb6274e 100644
--- a/include/linux/quota.h
+++ b/include/linux/quota.h
@@ -490,6 +490,9 @@ enum {
                                                  */
 #define DQUOT_NEGATIVE_USAGE    (1 << (DQUOT_STATE_LAST + 1))
                                                /* Allow negative quota usage */
+/* Do not track dirty dquots in a list */
+#define DQUOT_NOLIST_DIRTY      (1 << (DQUOT_STATE_LAST + 2))
+
 static inline unsigned int dquot_state_flag(unsigned int flags, int type)
 {
         return flags << type;