quota: reorder flags in quota state

Flags in struct quota_state keep flags for each quota type and
some common flags. This patch reorders typed flags:

Before:

0 USRQUOTA DQUOT_USAGE_ENABLED
1 USRQUOTA DQUOT_LIMITS_ENABLED
2 USRQUOTA DQUOT_SUSPENDED
3 GRPQUOTA DQUOT_USAGE_ENABLED
4 GRPQUOTA DQUOT_LIMITS_ENABLED
5 GRPQUOTA DQUOT_SUSPENDED
6          DQUOT_QUOTA_SYS_FILE
7          DQUOT_NEGATIVE_USAGE

After:

0 USRQUOTA DQUOT_USAGE_ENABLED
1 GRPQUOTA DQUOT_USAGE_ENABLED
2 USRQUOTA DQUOT_LIMITS_ENABLED
3 GRPQUOTA DQUOT_LIMITS_ENABLED
4 USRQUOTA DQUOT_SUSPENDED
5 GRPQUOTA DQUOT_SUSPENDED
6          DQUOT_QUOTA_SYS_FILE
7          DQUOT_NEGATIVE_USAGE

Now we can get bitmap of all enabled/suspended quota types without loop.
For example suspended: (flags / DQUOT_SUSPENDED) & ((1 << MAXQUOTAS) - 1).

add/remove: 0/1 grow/shrink: 3/11 up/down: 56/-215 (-159)
function                                     old     new   delta
__dquot_initialize                           423     447     +24
dquot_transfer                               181     197     +16
dquot_alloc_inode                            286     302     +16
dquot_reclaim_space_nodirty                  316     313      -3
dquot_claim_space_nodirty                    314     311      -3
dquot_resume                                 286     281      -5
dquot_free_inode                             332     324      -8
__dquot_alloc_space                          500     492      -8
dquot_disable                               1944    1929     -15
dquot_quota_enable                           252     236     -16
__dquot_free_space                           750     734     -16
dquot_writeback_dquots                       625     608     -17
__dquot_transfer                            1186    1154     -32
dquot_quota_sync                             299     261     -38
dquot_active.isra                             54       -     -54

Signed-off-by: Konstantin Khlebnikov <khlebnikov@yandex-team.ru>
Signed-off-by: Jan Kara <jack@suse.cz>

1 files changed, 25 insertions, 7 deletions

diff --git a/include/linux/quota.h b/include/linux/quota.h
index d534e8ed308a..a3374dc3a91b 100644
--- a/include/linux/quota.h
+++ b/include/linux/quota.h
@@ -389,7 +389,19 @@ struct quota_format_type {
         struct quota_format_type *qf_next;
 };
 
-/* Quota state flags - they actually come in two flavors - for users and groups */
+/**
+ * Quota state flags - they actually come in two flavors - for users and groups.
+ *
+ * Actual typed flags layout:
+ *                              USRQUOTA        GRPQUOTA
+ *  DQUOT_USAGE_ENABLED         0x0001          0x0002
+ *  DQUOT_LIMITS_ENABLED        0x0004          0x0008
+ *  DQUOT_SUSPENDED             0x0010          0x0020
+ *
+ * Following bits are used for non-typed flags:
+ *  DQUOT_QUOTA_SYS_FILE        0x0040
+ *  DQUOT_NEGATIVE_USAGE        0x0080
+ */
 enum {
         _DQUOT_USAGE_ENABLED = 0,               /* Track disk usage for users */
         _DQUOT_LIMITS_ENABLED,                  /* Enforce quota limits for users */
@@ -398,9 +410,9 @@ enum {
                                                  * memory to turn them on */
         _DQUOT_STATE_FLAGS
 };
-#define DQUOT_USAGE_ENABLED     (1 << _DQUOT_USAGE_ENABLED)
-#define DQUOT_LIMITS_ENABLED    (1 << _DQUOT_LIMITS_ENABLED)
-#define DQUOT_SUSPENDED         (1 << _DQUOT_SUSPENDED)
+#define DQUOT_USAGE_ENABLED     (1 << _DQUOT_USAGE_ENABLED * MAXQUOTAS)
+#define DQUOT_LIMITS_ENABLED    (1 << _DQUOT_LIMITS_ENABLED * MAXQUOTAS)
+#define DQUOT_SUSPENDED         (1 << _DQUOT_SUSPENDED * MAXQUOTAS)
 #define DQUOT_STATE_FLAGS       (DQUOT_USAGE_ENABLED | DQUOT_LIMITS_ENABLED | \
                                  DQUOT_SUSPENDED)
 /* Other quota flags */
@@ -414,15 +426,21 @@ enum {
                                                  */
 #define DQUOT_NEGATIVE_USAGE    (1 << (DQUOT_STATE_LAST + 1))
                                                /* Allow negative quota usage */
-
 static inline unsigned int dquot_state_flag(unsigned int flags, int type)
 {
-        return flags << _DQUOT_STATE_FLAGS * type;
+        return flags << type;
 }
 
 static inline unsigned int dquot_generic_flag(unsigned int flags, int type)
 {
-        return (flags >> _DQUOT_STATE_FLAGS * type) & DQUOT_STATE_FLAGS;
+        return (flags >> type) & DQUOT_STATE_FLAGS;
+}
+
+/* Bitmap of quota types where flag is set in flags */
+static __always_inline unsigned dquot_state_types(unsigned flags, unsigned flag)
+{
+        BUILD_BUG_ON_NOT_POWER_OF_2(flag);
+        return (flags / flag) & ((1 << MAXQUOTAS) - 1);
 }
 
 #ifdef CONFIG_QUOTA_NETLINK_INTERFACE