File: /Users/paulross/dev/linux/linux-3.13/include/linux/gfp.h

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       1: #ifndef __LINUX_GFP_H
       2: #define __LINUX_GFP_H
       3: 
       4: #include <linux/mmzone.h>
       5: #include <linux/stddef.h>
       6: #include <linux/linkage.h>
       7: #include <linux/topology.h>
       8: #include <linux/mmdebug.h>
       9: 
      10: struct vm_area_struct;
      11: 
      12: /* Plain integer GFP bitmasks. Do not use this directly. */
      13: #define ___GFP_DMA        0x01u
      14: #define ___GFP_HIGHMEM        0x02u
      15: #define ___GFP_DMA32        0x04u
      16: #define ___GFP_MOVABLE        0x08u
      17: #define ___GFP_WAIT        0x10u
      18: #define ___GFP_HIGH        0x20u
      19: #define ___GFP_IO        0x40u
      20: #define ___GFP_FS        0x80u
      21: #define ___GFP_COLD        0x100u
      22: #define ___GFP_NOWARN        0x200u
      23: #define ___GFP_REPEAT        0x400u
      24: #define ___GFP_NOFAIL        0x800u
      25: #define ___GFP_NORETRY        0x1000u
      26: #define ___GFP_MEMALLOC        0x2000u
      27: #define ___GFP_COMP        0x4000u
      28: #define ___GFP_ZERO        0x8000u
      29: #define ___GFP_NOMEMALLOC    0x10000u
      30: #define ___GFP_HARDWALL        0x20000u
      31: #define ___GFP_THISNODE        0x40000u
      32: #define ___GFP_RECLAIMABLE    0x80000u
      33: #define ___GFP_KMEMCG        0x100000u
      34: #define ___GFP_NOTRACK        0x200000u
      35: #define ___GFP_NO_KSWAPD    0x400000u
      36: #define ___GFP_OTHER_NODE    0x800000u
      37: #define ___GFP_WRITE        0x1000000u
      38: /* If the above are modified, __GFP_BITS_SHIFT may need updating */
      39: 
      40: /*
      41:  * GFP bitmasks..
      42:  *
      43:  * Zone modifiers (see linux/mmzone.h - low three bits)
      44:  *
      45:  * Do not put any conditional on these. If necessary modify the definitions
      46:  * without the underscores and use them consistently. The definitions here may
      47:  * be used in bit comparisons.
      48:  */
      49: #define __GFP_DMA    ((__force gfp_t)___GFP_DMA)
      50: #define __GFP_HIGHMEM    ((__force gfp_t)___GFP_HIGHMEM)
      51: #define __GFP_DMA32    ((__force gfp_t)___GFP_DMA32)
      52: #define __GFP_MOVABLE    ((__force gfp_t)___GFP_MOVABLE)  /* Page is movable */
      53: #define GFP_ZONEMASK    (__GFP_DMA|__GFP_HIGHMEM|__GFP_DMA32|__GFP_MOVABLE)
      54: /*
      55:  * Action modifiers - doesn't change the zoning
      56:  *
      57:  * __GFP_REPEAT: Try hard to allocate the memory, but the allocation attempt
      58:  * _might_ fail.  This depends upon the particular VM implementation.
      59:  *
      60:  * __GFP_NOFAIL: The VM implementation _must_ retry infinitely: the caller
      61:  * cannot handle allocation failures.  This modifier is deprecated and no new
      62:  * users should be added.
      63:  *
      64:  * __GFP_NORETRY: The VM implementation must not retry indefinitely.
      65:  *
      66:  * __GFP_MOVABLE: Flag that this page will be movable by the page migration
      67:  * mechanism or reclaimed
      68:  */
      69: #define __GFP_WAIT    ((__force gfp_t)___GFP_WAIT)    /* Can wait and reschedule? */
      70: #define __GFP_HIGH    ((__force gfp_t)___GFP_HIGH)    /* Should access emergency pools? */
      71: #define __GFP_IO    ((__force gfp_t)___GFP_IO)    /* Can start physical IO? */
      72: #define __GFP_FS    ((__force gfp_t)___GFP_FS)    /* Can call down to low-level FS? */
      73: #define __GFP_COLD    ((__force gfp_t)___GFP_COLD)    /* Cache-cold page required */
      74: #define __GFP_NOWARN    ((__force gfp_t)___GFP_NOWARN)    /* Suppress page allocation failure warning */
      75: #define __GFP_REPEAT    ((__force gfp_t)___GFP_REPEAT)    /* See above */
      76: #define __GFP_NOFAIL    ((__force gfp_t)___GFP_NOFAIL)    /* See above */
      77: #define __GFP_NORETRY    ((__force gfp_t)___GFP_NORETRY) /* See above */
      78: #define __GFP_MEMALLOC    ((__force gfp_t)___GFP_MEMALLOC)/* Allow access to emergency reserves */
      79: #define __GFP_COMP    ((__force gfp_t)___GFP_COMP)    /* Add compound page metadata */
      80: #define __GFP_ZERO    ((__force gfp_t)___GFP_ZERO)    /* Return zeroed page on success */
      81: #define __GFP_NOMEMALLOC ((__force gfp_t)___GFP_NOMEMALLOC) /* Don't use emergency reserves.
      82:                              * This takes precedence over the
      83:                              * __GFP_MEMALLOC flag if both are
      84:                              * set
      85:                              */
      86: #define __GFP_HARDWALL   ((__force gfp_t)___GFP_HARDWALL) /* Enforce hardwall cpuset memory allocs */
      87: #define __GFP_THISNODE    ((__force gfp_t)___GFP_THISNODE)/* No fallback, no policies */
      88: #define __GFP_RECLAIMABLE ((__force gfp_t)___GFP_RECLAIMABLE) /* Page is reclaimable */
      89: #define __GFP_NOTRACK    ((__force gfp_t)___GFP_NOTRACK)  /* Don't track with kmemcheck */
      90: 
      91: #define __GFP_NO_KSWAPD    ((__force gfp_t)___GFP_NO_KSWAPD)
      92: #define __GFP_OTHER_NODE ((__force gfp_t)___GFP_OTHER_NODE) /* On behalf of other node */
      93: #define __GFP_KMEMCG    ((__force gfp_t)___GFP_KMEMCG) /* Allocation comes from a memcg-accounted resource */
      94: #define __GFP_WRITE    ((__force gfp_t)___GFP_WRITE)    /* Allocator intends to dirty page */
      95: 
      96: /*
      97:  * This may seem redundant, but it's a way of annotating false positives vs.
      98:  * allocations that simply cannot be supported (e.g. page tables).
      99:  */
     100: #define __GFP_NOTRACK_FALSE_POSITIVE (__GFP_NOTRACK)
     101: 
     102: #define __GFP_BITS_SHIFT 25    /* Room for N __GFP_FOO bits */
     103: #define __GFP_BITS_MASK ((__force gfp_t)((1 << __GFP_BITS_SHIFT) - 1))
     104: 
     105: /* This equals 0, but use constants in case they ever change */
     106: #define GFP_NOWAIT    (GFP_ATOMIC & ~__GFP_HIGH)
     107: /* GFP_ATOMIC means both !wait (__GFP_WAIT not set) and use emergency pool */
     108: #define GFP_ATOMIC    (__GFP_HIGH)
     109: #define GFP_NOIO    (__GFP_WAIT)
     110: #define GFP_NOFS    (__GFP_WAIT | __GFP_IO)
     111: #define GFP_KERNEL    (__GFP_WAIT | __GFP_IO | __GFP_FS)
     112: #define GFP_TEMPORARY    (__GFP_WAIT | __GFP_IO | __GFP_FS | \
     113:              __GFP_RECLAIMABLE)
     114: #define GFP_USER    (__GFP_WAIT | __GFP_IO | __GFP_FS | __GFP_HARDWALL)
     115: #define GFP_HIGHUSER    (__GFP_WAIT | __GFP_IO | __GFP_FS | __GFP_HARDWALL | \
     116:              __GFP_HIGHMEM)
     117: #define GFP_HIGHUSER_MOVABLE    (__GFP_WAIT | __GFP_IO | __GFP_FS | \
     118:                  __GFP_HARDWALL | __GFP_HIGHMEM | \
     119:                  __GFP_MOVABLE)
     120: #define GFP_IOFS    (__GFP_IO | __GFP_FS)
     121: #define GFP_TRANSHUGE    (GFP_HIGHUSER_MOVABLE | __GFP_COMP | \
     122:              __GFP_NOMEMALLOC | __GFP_NORETRY | __GFP_NOWARN | \
     123:              __GFP_NO_KSWAPD)
     124: 
     125: #ifdef CONFIG_NUMA
     126: #define GFP_THISNODE    (__GFP_THISNODE | __GFP_NOWARN | __GFP_NORETRY)
     127: #else
     128: #define GFP_THISNODE    ((__force gfp_t)0)
     129: #endif
     130: 
     131: /* This mask makes up all the page movable related flags */
     132: #define GFP_MOVABLE_MASK (__GFP_RECLAIMABLE|__GFP_MOVABLE)
     133: 
     134: /* Control page allocator reclaim behavior */
     135: #define GFP_RECLAIM_MASK (__GFP_WAIT|__GFP_HIGH|__GFP_IO|__GFP_FS|\
            __GFP_NOWARN|__GFP_REPEAT|__GFP_NOFAIL|\
            __GFP_NORETRY|__GFP_MEMALLOC|__GFP_NOMEMALLOC)
     138: 
     139: /* Control slab gfp mask during early boot */
     140: #define GFP_BOOT_MASK (__GFP_BITS_MASK & ~(__GFP_WAIT|__GFP_IO|__GFP_FS))
     141: 
     142: /* Control allocation constraints */
     143: #define GFP_CONSTRAINT_MASK (__GFP_HARDWALL|__GFP_THISNODE)
     144: 
     145: /* Do not use these with a slab allocator */
     146: #define GFP_SLAB_BUG_MASK (__GFP_DMA32|__GFP_HIGHMEM|~__GFP_BITS_MASK)
     147: 
     148: /* Flag - indicates that the buffer will be suitable for DMA.  Ignored on some
     149:    platforms, used as appropriate on others */
     150: 
     151: #define GFP_DMA        __GFP_DMA
     152: 
     153: /* 4GB DMA on some platforms */
     154: #define GFP_DMA32    __GFP_DMA32
     155: 
     156: /* Convert GFP flags to their corresponding migrate type */
     157: static inline int allocflags_to_migratetype(gfp_t gfp_flags)
     158: {
     159:     WARN_ON((gfp_flags & GFP_MOVABLE_MASK) == GFP_MOVABLE_MASK);
     160: 
     161:     if (unlikely(page_group_by_mobility_disabled))
     162:         return MIGRATE_UNMOVABLE;
     163: 
     164:     /* Group based on mobility */
     165:     return (((gfp_flags & __GFP_MOVABLE) != 0) << 1) |
     166:         ((gfp_flags & __GFP_RECLAIMABLE) != 0);
     167: }
     168: 
     169: #ifdef CONFIG_HIGHMEM
     170: #define OPT_ZONE_HIGHMEM ZONE_HIGHMEM
     171: #else
     172: #define OPT_ZONE_HIGHMEM ZONE_NORMAL
     173: #endif
     174: 
     175: #ifdef CONFIG_ZONE_DMA
     176: #define OPT_ZONE_DMA ZONE_DMA
     177: #else
     178: #define OPT_ZONE_DMA ZONE_NORMAL
     179: #endif
     180: 
     181: #ifdef CONFIG_ZONE_DMA32
     182: #define OPT_ZONE_DMA32 ZONE_DMA32
     183: #else
     184: #define OPT_ZONE_DMA32 ZONE_NORMAL
     185: #endif
     186: 
     187: /*
     188:  * GFP_ZONE_TABLE is a word size bitstring that is used for looking up the
     189:  * zone to use given the lowest 4 bits of gfp_t. Entries are ZONE_SHIFT long
     190:  * and there are 16 of them to cover all possible combinations of
     191:  * __GFP_DMA, __GFP_DMA32, __GFP_MOVABLE and __GFP_HIGHMEM.
     192:  *
     193:  * The zone fallback order is MOVABLE=>HIGHMEM=>NORMAL=>DMA32=>DMA.
     194:  * But GFP_MOVABLE is not only a zone specifier but also an allocation
     195:  * policy. Therefore __GFP_MOVABLE plus another zone selector is valid.
     196:  * Only 1 bit of the lowest 3 bits (DMA,DMA32,HIGHMEM) can be set to "1".
     197:  *
     198:  *       bit       result
     199:  *       =================
     200:  *       0x0    => NORMAL
     201:  *       0x1    => DMA or NORMAL
     202:  *       0x2    => HIGHMEM or NORMAL
     203:  *       0x3    => BAD (DMA+HIGHMEM)
     204:  *       0x4    => DMA32 or DMA or NORMAL
     205:  *       0x5    => BAD (DMA+DMA32)
     206:  *       0x6    => BAD (HIGHMEM+DMA32)
     207:  *       0x7    => BAD (HIGHMEM+DMA32+DMA)
     208:  *       0x8    => NORMAL (MOVABLE+0)
     209:  *       0x9    => DMA or NORMAL (MOVABLE+DMA)
     210:  *       0xa    => MOVABLE (Movable is valid only if HIGHMEM is set too)
     211:  *       0xb    => BAD (MOVABLE+HIGHMEM+DMA)
     212:  *       0xc    => DMA32 (MOVABLE+DMA32)
     213:  *       0xd    => BAD (MOVABLE+DMA32+DMA)
     214:  *       0xe    => BAD (MOVABLE+DMA32+HIGHMEM)
     215:  *       0xf    => BAD (MOVABLE+DMA32+HIGHMEM+DMA)
     216:  *
     217:  * ZONES_SHIFT must be <= 2 on 32 bit platforms.
     218:  */
     219: 
     220: #if 16 * ZONES_SHIFT > BITS_PER_LONG
     221: #error ZONES_SHIFT too large to create GFP_ZONE_TABLE integer
     222: #endif
     223: 
     224: #define GFP_ZONE_TABLE ( \
     225:     (ZONE_NORMAL << 0 * ZONES_SHIFT)                      \
     226:     | (OPT_ZONE_DMA << ___GFP_DMA * ZONES_SHIFT)                  \
     227:     | (OPT_ZONE_HIGHMEM << ___GFP_HIGHMEM * ZONES_SHIFT)              \
     228:     | (OPT_ZONE_DMA32 << ___GFP_DMA32 * ZONES_SHIFT)              \
     229:     | (ZONE_NORMAL << ___GFP_MOVABLE * ZONES_SHIFT)                  \
     230:     | (OPT_ZONE_DMA << (___GFP_MOVABLE | ___GFP_DMA) * ZONES_SHIFT)          \
     231:     | (ZONE_MOVABLE << (___GFP_MOVABLE | ___GFP_HIGHMEM) * ZONES_SHIFT)   \
     232:     | (OPT_ZONE_DMA32 << (___GFP_MOVABLE | ___GFP_DMA32) * ZONES_SHIFT)   \
     233: )
     234: 
     235: /*
     236:  * GFP_ZONE_BAD is a bitmap for all combinations of __GFP_DMA, __GFP_DMA32
     237:  * __GFP_HIGHMEM and __GFP_MOVABLE that are not permitted. One flag per
     238:  * entry starting with bit 0. Bit is set if the combination is not
     239:  * allowed.
     240:  */
     241: #define GFP_ZONE_BAD ( \
     242:     1 << (___GFP_DMA | ___GFP_HIGHMEM)                      \
     243:     | 1 << (___GFP_DMA | ___GFP_DMA32)                      \
     244:     | 1 << (___GFP_DMA32 | ___GFP_HIGHMEM)                      \
     245:     | 1 << (___GFP_DMA | ___GFP_DMA32 | ___GFP_HIGHMEM)              \
     246:     | 1 << (___GFP_MOVABLE | ___GFP_HIGHMEM | ___GFP_DMA)              \
     247:     | 1 << (___GFP_MOVABLE | ___GFP_DMA32 | ___GFP_DMA)              \
     248:     | 1 << (___GFP_MOVABLE | ___GFP_DMA32 | ___GFP_HIGHMEM)              \
     249:     | 1 << (___GFP_MOVABLE | ___GFP_DMA32 | ___GFP_DMA | ___GFP_HIGHMEM)  \
     250: )
     251: 
     252: static inline enum zone_type gfp_zone(gfp_t flags)
     253: {
     254:     enum zone_type z;
     255:     int bit = (__force int) (flags & GFP_ZONEMASK);
     256: 
     257:     z = (GFP_ZONE_TABLE >> (bit * ZONES_SHIFT)) &
     258:                      ((1 << ZONES_SHIFT) - 1);
     259:     VM_BUG_ON((GFP_ZONE_BAD >> bit) & 1);
     260:     return z;
     261: }
     262: 
     263: /*
     264:  * There is only one page-allocator function, and two main namespaces to
     265:  * it. The alloc_page*() variants return 'struct page *' and as such
     266:  * can allocate highmem pages, the *get*page*() variants return
     267:  * virtual kernel addresses to the allocated page(s).
     268:  */
     269: 
     270: static inline int gfp_zonelist(gfp_t flags)
     271: {
     272:     if (IS_ENABLED(CONFIG_NUMA) && unlikely(flags & __GFP_THISNODE))
     273:         return 1;
     274: 
     275:     return 0;
     276: }
     277: 
     278: /*
     279:  * We get the zone list from the current node and the gfp_mask.
     280:  * This zone list contains a maximum of MAXNODES*MAX_NR_ZONES zones.
     281:  * There are two zonelists per node, one for all zones with memory and
     282:  * one containing just zones from the node the zonelist belongs to.
     283:  *
     284:  * For the normal case of non-DISCONTIGMEM systems the NODE_DATA() gets
     285:  * optimized to &contig_page_data at compile-time.
     286:  */
     287: static inline struct zonelist *node_zonelist(int nid, gfp_t flags)
     288: {
     289:     return NODE_DATA(nid)->node_zonelists + gfp_zonelist(flags);
     290: }
     291: 
     292: #ifndef HAVE_ARCH_FREE_PAGE
     293: static inline void arch_free_page(struct page *page, int order) { }
     294: #endif
     295: #ifndef HAVE_ARCH_ALLOC_PAGE
     296: static inline void arch_alloc_page(struct page *page, int order) { }
     297: #endif
     298: 
     299: struct page *
     300: __alloc_pages_nodemask(gfp_t gfp_mask, unsigned int order,
     301:                struct zonelist *zonelist, nodemask_t *nodemask);
     302: 
     303: static inline struct page *
     304: __alloc_pages(gfp_t gfp_mask, unsigned int order,
     305:         struct zonelist *zonelist)
     306: {
     307:     return __alloc_pages_nodemask(gfp_mask, order, zonelist, NULL);
     308: }
     309: 
     310: static inline struct page *alloc_pages_node(int nid, gfp_t gfp_mask,
     311:                         unsigned int order)
     312: {
     313:     /* Unknown node is current node */
     314:     if (nid < 0)
     315:         nid = numa_node_id();
     316: 
     317:     return __alloc_pages(gfp_mask, order, node_zonelist(nid, gfp_mask));
     318: }
     319: 
     320: static inline struct page *alloc_pages_exact_node(int nid, gfp_t gfp_mask,
     321:                         unsigned int order)
     322: {
     323:     VM_BUG_ON(nid < 0 || nid >= MAX_NUMNODES || !node_online(nid));
     324: 
     325:     return __alloc_pages(gfp_mask, order, node_zonelist(nid, gfp_mask));
     326: }
     327: 
     328: #ifdef CONFIG_NUMA
     329: extern struct page *alloc_pages_current(gfp_t gfp_mask, unsigned order);
     330: 
     331: static inline struct page *
     332: alloc_pages(gfp_t gfp_mask, unsigned int order)
     333: {
     334:     return alloc_pages_current(gfp_mask, order);
     335: }
     336: extern struct page *alloc_pages_vma(gfp_t gfp_mask, int order,
     337:             struct vm_area_struct *vma, unsigned long addr,
     338:             int node);
     339: #else
     340: #define alloc_pages(gfp_mask, order) \
     341:         alloc_pages_node(numa_node_id(), gfp_mask, order)
     342: #define alloc_pages_vma(gfp_mask, order, vma, addr, node)    \
     343:     alloc_pages(gfp_mask, order)
     344: #endif
     345: #define alloc_page(gfp_mask) alloc_pages(gfp_mask, 0)
     346: #define alloc_page_vma(gfp_mask, vma, addr)            \
     347:     alloc_pages_vma(gfp_mask, 0, vma, addr, numa_node_id())
     348: #define alloc_page_vma_node(gfp_mask, vma, addr, node)        \
     349:     alloc_pages_vma(gfp_mask, 0, vma, addr, node)
     350: 
     351: extern unsigned long __get_free_pages(gfp_t gfp_mask, unsigned int order);
     352: extern unsigned long get_zeroed_page(gfp_t gfp_mask);
     353: 
     354: void *alloc_pages_exact(size_t size, gfp_t gfp_mask);
     355: void free_pages_exact(void *virt, size_t size);
     356: /* This is different from alloc_pages_exact_node !!! */
     357: void *alloc_pages_exact_nid(int nid, size_t size, gfp_t gfp_mask);
     358: 
     359: #define __get_free_page(gfp_mask) \
     360:         __get_free_pages((gfp_mask), 0)
     361: 
     362: #define __get_dma_pages(gfp_mask, order) \
     363:         __get_free_pages((gfp_mask) | GFP_DMA, (order))
     364: 
     365: extern void __free_pages(struct page *page, unsigned int order);
     366: extern void free_pages(unsigned long addr, unsigned int order);
     367: extern void free_hot_cold_page(struct page *page, int cold);
     368: extern void free_hot_cold_page_list(struct list_head *list, int cold);
     369: 
     370: extern void __free_memcg_kmem_pages(struct page *page, unsigned int order);
     371: extern void free_memcg_kmem_pages(unsigned long addr, unsigned int order);
     372: 
     373: #define __free_page(page) __free_pages((page), 0)
     374: #define free_page(addr) free_pages((addr), 0)
     375: 
     376: void page_alloc_init(void);
     377: void drain_zone_pages(struct zone *zone, struct per_cpu_pages *pcp);
     378: void drain_all_pages(void);
     379: void drain_local_pages(void *dummy);
     380: 
     381: /*
     382:  * gfp_allowed_mask is set to GFP_BOOT_MASK during early boot to restrict what
     383:  * GFP flags are used before interrupts are enabled. Once interrupts are
     384:  * enabled, it is set to __GFP_BITS_MASK while the system is running. During
     385:  * hibernation, it is used by PM to avoid I/O during memory allocation while
     386:  * devices are suspended.
     387:  */
     388: extern gfp_t gfp_allowed_mask;
     389: 
     390: /* Returns true if the gfp_mask allows use of ALLOC_NO_WATERMARK */
     391: bool gfp_pfmemalloc_allowed(gfp_t gfp_mask);
     392: 
     393: extern void pm_restrict_gfp_mask(void);
     394: extern void pm_restore_gfp_mask(void);
     395: 
     396: #ifdef CONFIG_PM_SLEEP
     397: extern bool pm_suspended_storage(void);
     398: #else
     399: static inline bool pm_suspended_storage(void)
     400: {
     401:     return false;
     402: }
     403: #endif /* CONFIG_PM_SLEEP */
     404: 
     405: #ifdef CONFIG_CMA
     406: 
     407: /* The below functions must be run on a range from a single zone. */
     408: extern int alloc_contig_range(unsigned long start, unsigned long end,
     409:                   unsigned migratetype);
     410: extern void free_contig_range(unsigned long pfn, unsigned nr_pages);
     411: 
     412: /* CMA stuff */
     413: extern void init_cma_reserved_pageblock(struct page *page);
     414: 
     415: #endif
     416: 
     417: #endif /* __LINUX_GFP_H */
     418: