mm: introduce __GFP_MEMALLOC to allow access to emergency reserves

[deliverable/linux.git] / include / linux / gfp.h

diff --git a/include/linux/gfp.h b/include/linux/gfp.h
index 1e49be49d3247cb74cc798aa2772a085102851a5..cbd7400e58620bf303ec216b6abd47200668c574 100644 (file)
--- a/include/linux/gfp.h
+++ b/include/linux/gfp.h
@@ -23,6 +23,7 @@ struct vm_area_struct;
 #define ___GFP_REPEAT          0x400u
 #define ___GFP_NOFAIL          0x800u
 #define ___GFP_NORETRY         0x1000u
+#define ___GFP_MEMALLOC                0x2000u
 #define ___GFP_COMP            0x4000u
 #define ___GFP_ZERO            0x8000u
 #define ___GFP_NOMEMALLOC      0x10000u
@@ -76,9 +77,14 @@ struct vm_area_struct;
 #define __GFP_REPEAT   ((__force gfp_t)___GFP_REPEAT)  /* See above */
 #define __GFP_NOFAIL   ((__force gfp_t)___GFP_NOFAIL)  /* See above */
 #define __GFP_NORETRY  ((__force gfp_t)___GFP_NORETRY) /* See above */
+#define __GFP_MEMALLOC ((__force gfp_t)___GFP_MEMALLOC)/* Allow access to emergency reserves */
 #define __GFP_COMP     ((__force gfp_t)___GFP_COMP)    /* Add compound page metadata */
 #define __GFP_ZERO     ((__force gfp_t)___GFP_ZERO)    /* Return zeroed page on success */
-#define __GFP_NOMEMALLOC ((__force gfp_t)___GFP_NOMEMALLOC) /* Don't use emergency reserves */
+#define __GFP_NOMEMALLOC ((__force gfp_t)___GFP_NOMEMALLOC) /* Don't use emergency reserves.
+                                                        * This takes precedence over the
+                                                        * __GFP_MEMALLOC flag if both are
+                                                        * set
+                                                        */
 #define __GFP_HARDWALL   ((__force gfp_t)___GFP_HARDWALL) /* Enforce hardwall cpuset memory allocs */
 #define __GFP_THISNODE ((__force gfp_t)___GFP_THISNODE)/* No fallback, no policies */
 #define __GFP_RECLAIMABLE ((__force gfp_t)___GFP_RECLAIMABLE) /* Page is reclaimable */
@@ -129,7 +135,7 @@ struct vm_area_struct;
 /* Control page allocator reclaim behavior */
 #define GFP_RECLAIM_MASK (__GFP_WAIT|__GFP_HIGH|__GFP_IO|__GFP_FS|\
                        __GFP_NOWARN|__GFP_REPEAT|__GFP_NOFAIL|\
-                       __GFP_NORETRY|__GFP_NOMEMALLOC)
+                       __GFP_NORETRY|__GFP_MEMALLOC|__GFP_NOMEMALLOC)
 
 /* Control slab gfp mask during early boot */
 #define GFP_BOOT_MASK (__GFP_BITS_MASK & ~(__GFP_WAIT|__GFP_IO|__GFP_FS))