1 files changed, 119 insertions, 31 deletions

diff --git a/include/linux/gfp.h b/include/linux/gfp.h
index 80e14b8c2e78..cfdb35d71bca 100644
--- a/include/linux/gfp.h
+++ b/include/linux/gfp.h
@@ -5,6 +5,7 @@
 #include <linux/stddef.h>
 #include <linux/linkage.h>
 #include <linux/topology.h>
+#include <linux/mmdebug.h>
 
 struct vm_area_struct;
 
@@ -20,7 +21,8 @@ struct vm_area_struct;
 #define __GFP_DMA       ((__force gfp_t)0x01u)
 #define __GFP_HIGHMEM   ((__force gfp_t)0x02u)
 #define __GFP_DMA32     ((__force gfp_t)0x04u)
-
+#define __GFP_MOVABLE   ((__force gfp_t)0x08u)  /* Page is movable */
+#define GFP_ZONEMASK    (__GFP_DMA|__GFP_HIGHMEM|__GFP_DMA32|__GFP_MOVABLE)
 /*
  * Action modifiers - doesn't change the zoning
  *
@@ -50,7 +52,6 @@ struct vm_area_struct;
 #define __GFP_HARDWALL   ((__force gfp_t)0x20000u) /* Enforce hardwall cpuset memory allocs */
 #define __GFP_THISNODE  ((__force gfp_t)0x40000u)/* No fallback, no policies */
 #define __GFP_RECLAIMABLE ((__force gfp_t)0x80000u) /* Page is reclaimable */
-#define __GFP_MOVABLE   ((__force gfp_t)0x100000u)  /* Page is movable */
 
 #ifdef CONFIG_KMEMCHECK
 #define __GFP_NOTRACK   ((__force gfp_t)0x200000u)  /* Don't track with kmemcheck */
@@ -127,24 +128,105 @@ static inline int allocflags_to_migratetype(gfp_t gfp_flags)
                 ((gfp_flags & __GFP_RECLAIMABLE) != 0);
 }
 
-static inline enum zone_type gfp_zone(gfp_t flags)
-{
+#ifdef CONFIG_HIGHMEM
+#define OPT_ZONE_HIGHMEM ZONE_HIGHMEM
+#else
+#define OPT_ZONE_HIGHMEM ZONE_NORMAL
+#endif
+
 #ifdef CONFIG_ZONE_DMA
-        if (flags & __GFP_DMA)
-                return ZONE_DMA;
+#define OPT_ZONE_DMA ZONE_DMA
+#else
+#define OPT_ZONE_DMA ZONE_NORMAL
 #endif
+
 #ifdef CONFIG_ZONE_DMA32
-        if (flags & __GFP_DMA32)
-                return ZONE_DMA32;
+#define OPT_ZONE_DMA32 ZONE_DMA32
+#else
+#define OPT_ZONE_DMA32 ZONE_NORMAL
 #endif
-        if ((flags & (__GFP_HIGHMEM | __GFP_MOVABLE)) ==
-                        (__GFP_HIGHMEM | __GFP_MOVABLE))
-                return ZONE_MOVABLE;
-#ifdef CONFIG_HIGHMEM
-        if (flags & __GFP_HIGHMEM)
-                return ZONE_HIGHMEM;
+
+/*
+ * GFP_ZONE_TABLE is a word size bitstring that is used for looking up the
+ * zone to use given the lowest 4 bits of gfp_t. Entries are ZONE_SHIFT long
+ * and there are 16 of them to cover all possible combinations of
+ * __GFP_DMA, __GFP_DMA32, __GFP_MOVABLE and __GFP_HIGHMEM
+ *
+ * The zone fallback order is MOVABLE=>HIGHMEM=>NORMAL=>DMA32=>DMA.
+ * But GFP_MOVABLE is not only a zone specifier but also an allocation
+ * policy. Therefore __GFP_MOVABLE plus another zone selector is valid.
+ * Only 1bit of the lowest 3 bit (DMA,DMA32,HIGHMEM) can be set to "1".
+ *
+ *       bit       result
+ *       =================
+ *       0x0    => NORMAL
+ *       0x1    => DMA or NORMAL
+ *       0x2    => HIGHMEM or NORMAL
+ *       0x3    => BAD (DMA+HIGHMEM)
+ *       0x4    => DMA32 or DMA or NORMAL
+ *       0x5    => BAD (DMA+DMA32)
+ *       0x6    => BAD (HIGHMEM+DMA32)
+ *       0x7    => BAD (HIGHMEM+DMA32+DMA)
+ *       0x8    => NORMAL (MOVABLE+0)
+ *       0x9    => DMA or NORMAL (MOVABLE+DMA)
+ *       0xa    => MOVABLE (Movable is valid only if HIGHMEM is set too)
+ *       0xb    => BAD (MOVABLE+HIGHMEM+DMA)
+ *       0xc    => DMA32 (MOVABLE+HIGHMEM+DMA32)
+ *       0xd    => BAD (MOVABLE+DMA32+DMA)
+ *       0xe    => BAD (MOVABLE+DMA32+HIGHMEM)
+ *       0xf    => BAD (MOVABLE+DMA32+HIGHMEM+DMA)
+ *
+ * ZONES_SHIFT must be <= 2 on 32 bit platforms.
+ */
+
+#if 16 * ZONES_SHIFT > BITS_PER_LONG
+#error ZONES_SHIFT too large to create GFP_ZONE_TABLE integer
+#endif
+
+#define GFP_ZONE_TABLE ( \
+        (ZONE_NORMAL << 0 * ZONES_SHIFT)                                \
+        | (OPT_ZONE_DMA << __GFP_DMA * ZONES_SHIFT)                     \
+        | (OPT_ZONE_HIGHMEM << __GFP_HIGHMEM * ZONES_SHIFT)             \
+        | (OPT_ZONE_DMA32 << __GFP_DMA32 * ZONES_SHIFT)                 \
+        | (ZONE_NORMAL << __GFP_MOVABLE * ZONES_SHIFT)                  \
+        | (OPT_ZONE_DMA << (__GFP_MOVABLE | __GFP_DMA) * ZONES_SHIFT)   \
+        | (ZONE_MOVABLE << (__GFP_MOVABLE | __GFP_HIGHMEM) * ZONES_SHIFT)\
+        | (OPT_ZONE_DMA32 << (__GFP_MOVABLE | __GFP_DMA32) * ZONES_SHIFT)\
+)
+
+/*
+ * GFP_ZONE_BAD is a bitmap for all combination of __GFP_DMA, __GFP_DMA32
+ * __GFP_HIGHMEM and __GFP_MOVABLE that are not permitted. One flag per
+ * entry starting with bit 0. Bit is set if the combination is not
+ * allowed.
+ */
+#define GFP_ZONE_BAD ( \
+        1 << (__GFP_DMA | __GFP_HIGHMEM)                                \
+        | 1 << (__GFP_DMA | __GFP_DMA32)                                \
+        | 1 << (__GFP_DMA32 | __GFP_HIGHMEM)                            \
+        | 1 << (__GFP_DMA | __GFP_DMA32 | __GFP_HIGHMEM)                \
+        | 1 << (__GFP_MOVABLE | __GFP_HIGHMEM | __GFP_DMA)              \
+        | 1 << (__GFP_MOVABLE | __GFP_DMA32 | __GFP_DMA)                \
+        | 1 << (__GFP_MOVABLE | __GFP_DMA32 | __GFP_HIGHMEM)            \
+        | 1 << (__GFP_MOVABLE | __GFP_DMA32 | __GFP_DMA | __GFP_HIGHMEM)\
+)
+
+static inline enum zone_type gfp_zone(gfp_t flags)
+{
+        enum zone_type z;
+        int bit = flags & GFP_ZONEMASK;
+
+        z = (GFP_ZONE_TABLE >> (bit * ZONES_SHIFT)) &
+                                         ((1 << ZONES_SHIFT) - 1);
+
+        if (__builtin_constant_p(bit))
+                BUILD_BUG_ON((GFP_ZONE_BAD >> bit) & 1);
+        else {
+#ifdef CONFIG_DEBUG_VM
+                BUG_ON((GFP_ZONE_BAD >> bit) & 1);
 #endif
-        return ZONE_NORMAL;
+        }
+        return z;
 }
 
 /*
@@ -184,30 +266,19 @@ static inline void arch_alloc_page(struct page *page, int order) { }
 #endif
 
 struct page *
-__alloc_pages_internal(gfp_t gfp_mask, unsigned int order,
+__alloc_pages_nodemask(gfp_t gfp_mask, unsigned int order,
                        struct zonelist *zonelist, nodemask_t *nodemask);
 
 static inline struct page *
 __alloc_pages(gfp_t gfp_mask, unsigned int order,
                 struct zonelist *zonelist)
 {
-        return __alloc_pages_internal(gfp_mask, order, zonelist, NULL);
+        return __alloc_pages_nodemask(gfp_mask, order, zonelist, NULL);
 }
 
-static inline struct page *
-__alloc_pages_nodemask(gfp_t gfp_mask, unsigned int order,
-                struct zonelist *zonelist, nodemask_t *nodemask)
-{
-        return __alloc_pages_internal(gfp_mask, order, zonelist, nodemask);
-}
-
-
 static inline struct page *alloc_pages_node(int nid, gfp_t gfp_mask,
                                                 unsigned int order)
 {
-        if (unlikely(order >= MAX_ORDER))
-                return NULL;
-
         /* Unknown node is current node */
         if (nid < 0)
                 nid = numa_node_id();
@@ -215,15 +286,20 @@ static inline struct page *alloc_pages_node(int nid, gfp_t gfp_mask,
         return __alloc_pages(gfp_mask, order, node_zonelist(nid, gfp_mask));
 }
 
+static inline struct page *alloc_pages_exact_node(int nid, gfp_t gfp_mask,
+                                                unsigned int order)
+{
+        VM_BUG_ON(nid < 0 || nid >= MAX_NUMNODES);
+
+        return __alloc_pages(gfp_mask, order, node_zonelist(nid, gfp_mask));
+}
+
 #ifdef CONFIG_NUMA
 extern struct page *alloc_pages_current(gfp_t gfp_mask, unsigned order);
 
 static inline struct page *
 alloc_pages(gfp_t gfp_mask, unsigned int order)
 {
-        if (unlikely(order >= MAX_ORDER))
-                return NULL;
-
         return alloc_pages_current(gfp_mask, order);
 }
 extern struct page *alloc_page_vma(gfp_t gfp_mask,
@@ -260,4 +336,16 @@ void drain_zone_pages(struct zone *zone, struct per_cpu_pages *pcp);
 void drain_all_pages(void);
 void drain_local_pages(void *dummy);
 
+extern bool oom_killer_disabled;
+
+static inline void oom_killer_disable(void)
+{
+        oom_killer_disabled = true;
+}
+
+static inline void oom_killer_enable(void)
+{
+        oom_killer_disabled = false;
+}
+
 #endif /* __LINUX_GFP_H */