mm: fix sparse warnings on GFP_ZONE_TABLE/BAD

Introduce ___GFP_* masks in order for gfp_t to not be mixed with plain
integers which causes a lot of warnings like the following:

 warning: restricted gfp_t degrades to integer

Signed-off-by: Namhyung Kim <namhyung@gmail.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

1 files changed, 63 insertions, 42 deletions

diff --git a/include/linux/gfp.h b/include/linux/gfp.h
index 975609cb8548..e8713d55360a 100644
--- a/include/linux/gfp.h
+++ b/include/linux/gfp.h
@@ -9,6 +9,32 @@
 
 struct vm_area_struct;
 
+/* Plain integer GFP bitmasks. Do not use this directly. */
+#define ___GFP_DMA              0x01u
+#define ___GFP_HIGHMEM          0x02u
+#define ___GFP_DMA32            0x04u
+#define ___GFP_MOVABLE          0x08u
+#define ___GFP_WAIT             0x10u
+#define ___GFP_HIGH             0x20u
+#define ___GFP_IO               0x40u
+#define ___GFP_FS               0x80u
+#define ___GFP_COLD             0x100u
+#define ___GFP_NOWARN           0x200u
+#define ___GFP_REPEAT           0x400u
+#define ___GFP_NOFAIL           0x800u
+#define ___GFP_NORETRY          0x1000u
+#define ___GFP_COMP             0x4000u
+#define ___GFP_ZERO             0x8000u
+#define ___GFP_NOMEMALLOC       0x10000u
+#define ___GFP_HARDWALL         0x20000u
+#define ___GFP_THISNODE         0x40000u
+#define ___GFP_RECLAIMABLE      0x80000u
+#ifdef CONFIG_KMEMCHECK
+#define ___GFP_NOTRACK          0x200000u
+#else
+#define ___GFP_NOTRACK          0
+#endif
+
 /*
  * GFP bitmasks..
  *
@@ -18,10 +44,10 @@ struct vm_area_struct;
  * without the underscores and use them consistently. The definitions here may
  * be used in bit comparisons.
  */
-#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_DMA       ((__force gfp_t)___GFP_DMA)
+#define __GFP_HIGHMEM   ((__force gfp_t)___GFP_HIGHMEM)
+#define __GFP_DMA32     ((__force gfp_t)___GFP_DMA32)
+#define __GFP_MOVABLE   ((__force gfp_t)___GFP_MOVABLE)  /* Page is movable */
 #define GFP_ZONEMASK    (__GFP_DMA|__GFP_HIGHMEM|__GFP_DMA32|__GFP_MOVABLE)
 /*
  * Action modifiers - doesn't change the zoning
@@ -38,27 +64,22 @@ struct vm_area_struct;
  * __GFP_MOVABLE: Flag that this page will be movable by the page migration
  * mechanism or reclaimed
  */
-#define __GFP_WAIT      ((__force gfp_t)0x10u)  /* Can wait and reschedule? */
-#define __GFP_HIGH      ((__force gfp_t)0x20u)  /* Should access emergency pools? */
-#define __GFP_IO        ((__force gfp_t)0x40u)  /* Can start physical IO? */
-#define __GFP_FS        ((__force gfp_t)0x80u)  /* Can call down to low-level FS? */
-#define __GFP_COLD      ((__force gfp_t)0x100u) /* Cache-cold page required */
-#define __GFP_NOWARN    ((__force gfp_t)0x200u) /* Suppress page allocation failure warning */
-#define __GFP_REPEAT    ((__force gfp_t)0x400u) /* See above */
-#define __GFP_NOFAIL    ((__force gfp_t)0x800u) /* See above */
-#define __GFP_NORETRY   ((__force gfp_t)0x1000u)/* See above */
-#define __GFP_COMP      ((__force gfp_t)0x4000u)/* Add compound page metadata */
-#define __GFP_ZERO      ((__force gfp_t)0x8000u)/* Return zeroed page on success */
-#define __GFP_NOMEMALLOC ((__force gfp_t)0x10000u) /* Don't use emergency reserves */
-#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 */
-
-#ifdef CONFIG_KMEMCHECK
-#define __GFP_NOTRACK   ((__force gfp_t)0x200000u)  /* Don't track with kmemcheck */
-#else
-#define __GFP_NOTRACK   ((__force gfp_t)0)
-#endif
+#define __GFP_WAIT      ((__force gfp_t)___GFP_WAIT)    /* Can wait and reschedule? */
+#define __GFP_HIGH      ((__force gfp_t)___GFP_HIGH)    /* Should access emergency pools? */
+#define __GFP_IO        ((__force gfp_t)___GFP_IO)      /* Can start physical IO? */
+#define __GFP_FS        ((__force gfp_t)___GFP_FS)      /* Can call down to low-level FS? */
+#define __GFP_COLD      ((__force gfp_t)___GFP_COLD)    /* Cache-cold page required */
+#define __GFP_NOWARN    ((__force gfp_t)___GFP_NOWARN)  /* Suppress page allocation failure warning */
+#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_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_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 */
+#define __GFP_NOTRACK   ((__force gfp_t)___GFP_NOTRACK)  /* Don't track with kmemcheck */
 
 /*
  * This may seem redundant, but it's a way of annotating false positives vs.
@@ -186,14 +207,14 @@ static inline int allocflags_to_migratetype(gfp_t gfp_flags)
 #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)\
+        (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)   \
 )
 
 /*
@@ -203,20 +224,20 @@ static inline int allocflags_to_migratetype(gfp_t gfp_flags)
  * 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)\
+        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;
+        int bit = (__force int) (flags & GFP_ZONEMASK);
 
         z = (GFP_ZONE_TABLE >> (bit * ZONES_SHIFT)) &
                                          ((1 << ZONES_SHIFT) - 1);