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Diffstat (limited to 'include/linux/gfp.h')
| -rw-r--r-- | include/linux/gfp.h | 584 |
1 files changed, 584 insertions, 0 deletions
diff --git a/include/linux/gfp.h b/include/linux/gfp.h new file mode 100644 index 000000000000..a5f251d76018 --- /dev/null +++ b/include/linux/gfp.h @@ -0,0 +1,584 @@ +#ifndef __LINUX_GFP_H +#define __LINUX_GFP_H + +#include <linux/mmdebug.h> +#include <linux/mmzone.h> +#include <linux/stddef.h> +#include <linux/linkage.h> +#include <linux/topology.h> + +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_RECLAIMABLE 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_MEMALLOC 0x2000u +#define ___GFP_COMP 0x4000u +#define ___GFP_ZERO 0x8000u +#define ___GFP_NOMEMALLOC 0x10000u +#define ___GFP_HARDWALL 0x20000u +#define ___GFP_THISNODE 0x40000u +#define ___GFP_ATOMIC 0x80000u +#define ___GFP_NOACCOUNT 0x100000u +#define ___GFP_NOTRACK 0x200000u +#define ___GFP_DIRECT_RECLAIM 0x400000u +#define ___GFP_OTHER_NODE 0x800000u +#define ___GFP_WRITE 0x1000000u +#define ___GFP_KSWAPD_RECLAIM 0x2000000u +#define ___GFP_CMA 0x4000000u +/* If the above are modified, __GFP_BITS_SHIFT may need updating */ + +/* + * Physical address zone modifiers (see linux/mmzone.h - low four bits) + * + * Do not put any conditional on these. If necessary modify the definitions + * without the underscores and use them consistently. The definitions here may + * be used in bit comparisons. + */ +#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_MOVABLE ((__force gfp_t)___GFP_MOVABLE) /* ZONE_MOVABLE allowed */ +#define __GFP_CMA ((__force gfp_t)___GFP_CMA) +#define GFP_ZONEMASK (__GFP_DMA|__GFP_HIGHMEM|__GFP_DMA32|__GFP_MOVABLE| \ + __GFP_CMA) +/* + * Page mobility and placement hints + * + * These flags provide hints about how mobile the page is. Pages with similar + * mobility are placed within the same pageblocks to minimise problems due + * to external fragmentation. + * + * __GFP_MOVABLE (also a zone modifier) indicates that the page can be + * moved by page migration during memory compaction or can be reclaimed. + * + * __GFP_RECLAIMABLE is used for slab allocations that specify + * SLAB_RECLAIM_ACCOUNT and whose pages can be freed via shrinkers. + * + * __GFP_WRITE indicates the caller intends to dirty the page. Where possible, + * these pages will be spread between local zones to avoid all the dirty + * pages being in one zone (fair zone allocation policy). + * + * __GFP_HARDWALL enforces the cpuset memory allocation policy. + * + * __GFP_THISNODE forces the allocation to be satisified from the requested + * node with no fallbacks or placement policy enforcements. + */ +#define __GFP_RECLAIMABLE ((__force gfp_t)___GFP_RECLAIMABLE) +#define __GFP_WRITE ((__force gfp_t)___GFP_WRITE) +#define __GFP_HARDWALL ((__force gfp_t)___GFP_HARDWALL) +#define __GFP_THISNODE ((__force gfp_t)___GFP_THISNODE) + +/* + * Watermark modifiers -- controls access to emergency reserves + * + * __GFP_HIGH indicates that the caller is high-priority and that granting + * the request is necessary before the system can make forward progress. + * For example, creating an IO context to clean pages. + * + * __GFP_ATOMIC indicates that the caller cannot reclaim or sleep and is + * high priority. Users are typically interrupt handlers. This may be + * used in conjunction with __GFP_HIGH + * + * __GFP_MEMALLOC allows access to all memory. This should only be used when + * the caller guarantees the allocation will allow more memory to be freed + * very shortly e.g. process exiting or swapping. Users either should + * be the MM or co-ordinating closely with the VM (e.g. swap over NFS). + * + * __GFP_NOMEMALLOC is used to explicitly forbid access to emergency reserves. + * This takes precedence over the __GFP_MEMALLOC flag if both are set. + * + * __GFP_NOACCOUNT ignores the accounting for kmemcg limit enforcement. + */ +#define __GFP_ATOMIC ((__force gfp_t)___GFP_ATOMIC) +#define __GFP_HIGH ((__force gfp_t)___GFP_HIGH) +#define __GFP_MEMALLOC ((__force gfp_t)___GFP_MEMALLOC) +#define __GFP_NOMEMALLOC ((__force gfp_t)___GFP_NOMEMALLOC) +#define __GFP_NOACCOUNT ((__force gfp_t)___GFP_NOACCOUNT) + +/* + * Reclaim modifiers + * + * __GFP_IO can start physical IO. + * + * __GFP_FS can call down to the low-level FS. Clearing the flag avoids the + * allocator recursing into the filesystem which might already be holding + * locks. + * + * __GFP_DIRECT_RECLAIM indicates that the caller may enter direct reclaim. + * This flag can be cleared to avoid unnecessary delays when a fallback + * option is available. + * + * __GFP_KSWAPD_RECLAIM indicates that the caller wants to wake kswapd when + * the low watermark is reached and have it reclaim pages until the high + * watermark is reached. A caller may wish to clear this flag when fallback + * options are available and the reclaim is likely to disrupt the system. The + * canonical example is THP allocation where a fallback is cheap but + * reclaim/compaction may cause indirect stalls. + * + * __GFP_RECLAIM is shorthand to allow/forbid both direct and kswapd reclaim. + * + * __GFP_REPEAT: Try hard to allocate the memory, but the allocation attempt + * _might_ fail. This depends upon the particular VM implementation. + * + * __GFP_NOFAIL: The VM implementation _must_ retry infinitely: the caller + * cannot handle allocation failures. New users should be evaluated carefully + * (and the flag should be used only when there is no reasonable failure + * policy) but it is definitely preferable to use the flag rather than + * opencode endless loop around allocator. + * + * __GFP_NORETRY: The VM implementation must not retry indefinitely and will + * return NULL when direct reclaim and memory compaction have failed to allow + * the allocation to succeed. The OOM killer is not called with the current + * implementation. + */ +#define __GFP_IO ((__force gfp_t)___GFP_IO) +#define __GFP_FS ((__force gfp_t)___GFP_FS) +#define __GFP_DIRECT_RECLAIM ((__force gfp_t)___GFP_DIRECT_RECLAIM) /* Caller can reclaim */ +#define __GFP_KSWAPD_RECLAIM ((__force gfp_t)___GFP_KSWAPD_RECLAIM) /* kswapd can wake */ +#define __GFP_RECLAIM ((__force gfp_t)(___GFP_DIRECT_RECLAIM|___GFP_KSWAPD_RECLAIM)) +#define __GFP_REPEAT ((__force gfp_t)___GFP_REPEAT) +#define __GFP_NOFAIL ((__force gfp_t)___GFP_NOFAIL) +#define __GFP_NORETRY ((__force gfp_t)___GFP_NORETRY) + +/* + * Action modifiers + * + * __GFP_COLD indicates that the caller does not expect to be used in the near + * future. Where possible, a cache-cold page will be returned. + * + * __GFP_NOWARN suppresses allocation failure reports. + * + * __GFP_COMP address compound page metadata. + * + * __GFP_ZERO returns a zeroed page on success. + * + * __GFP_NOTRACK avoids tracking with kmemcheck. + * + * __GFP_NOTRACK_FALSE_POSITIVE is an alias of __GFP_NOTRACK. It's a means of + * distinguishing in the source between false positives and allocations that + * cannot be supported (e.g. page tables). + * + * __GFP_OTHER_NODE is for allocations that are on a remote node but that + * should not be accounted for as a remote allocation in vmstat. A + * typical user would be khugepaged collapsing a huge page on a remote + * node. + */ +#define __GFP_COLD ((__force gfp_t)___GFP_COLD) +#define __GFP_NOWARN ((__force gfp_t)___GFP_NOWARN) +#define __GFP_COMP ((__force gfp_t)___GFP_COMP) +#define __GFP_ZERO ((__force gfp_t)___GFP_ZERO) +#define __GFP_NOTRACK ((__force gfp_t)___GFP_NOTRACK) +#define __GFP_NOTRACK_FALSE_POSITIVE (__GFP_NOTRACK) +#define __GFP_OTHER_NODE ((__force gfp_t)___GFP_OTHER_NODE) + +/* Room for N __GFP_FOO bits */ +#define __GFP_BITS_SHIFT 27 +#define __GFP_BITS_MASK ((__force gfp_t)((1 << __GFP_BITS_SHIFT) - 1)) + +/* + * Useful GFP flag combinations that are commonly used. It is recommended + * that subsystems start with one of these combinations and then set/clear + * __GFP_FOO flags as necessary. + * + * GFP_ATOMIC users can not sleep and need the allocation to succeed. A lower + * watermark is applied to allow access to "atomic reserves" + * + * GFP_KERNEL is typical for kernel-internal allocations. The caller requires + * ZONE_NORMAL or a lower zone for direct access but can direct reclaim. + * + * GFP_NOWAIT is for kernel allocations that should not stall for direct + * reclaim, start physical IO or use any filesystem callback. + * + * GFP_NOIO will use direct reclaim to discard clean pages or slab pages + * that do not require the starting of any physical IO. + * + * GFP_NOFS will use direct reclaim but will not use any filesystem interfaces. + * + * GFP_USER is for userspace allocations that also need to be directly + * accessibly by the kernel or hardware. It is typically used by hardware + * for buffers that are mapped to userspace (e.g. graphics) that hardware + * still must DMA to. cpuset limits are enforced for these allocations. + * + * GFP_DMA exists for historical reasons and should be avoided where possible. + * The flags indicates that the caller requires that the lowest zone be + * used (ZONE_DMA or 16M on x86-64). Ideally, this would be removed but + * it would require careful auditing as some users really require it and + * others use the flag to avoid lowmem reserves in ZONE_DMA and treat the + * lowest zone as a type of emergency reserve. + * + * GFP_DMA32 is similar to GFP_DMA except that the caller requires a 32-bit + * address. + * + * GFP_HIGHUSER is for userspace allocations that may be mapped to userspace, + * do not need to be directly accessible by the kernel but that cannot + * move once in use. An example may be a hardware allocation that maps + * data directly into userspace but has no addressing limitations. + * + * GFP_HIGHUSER_MOVABLE is for userspace allocations that the kernel does not + * need direct access to but can use kmap() when access is required. They + * are expected to be movable via page reclaim or page migration. Typically, + * pages on the LRU would also be allocated with GFP_HIGHUSER_MOVABLE. + * + * GFP_TRANSHUGE is used for THP allocations. They are compound allocations + * that will fail quickly if memory is not available and will not wake + * kswapd on failure. + */ +#define GFP_ATOMIC (__GFP_HIGH|__GFP_ATOMIC|__GFP_KSWAPD_RECLAIM) +#define GFP_KERNEL (__GFP_RECLAIM | __GFP_IO | __GFP_FS) +#define GFP_NOWAIT (__GFP_KSWAPD_RECLAIM) +#define GFP_NOIO (__GFP_RECLAIM) +#define GFP_NOFS (__GFP_RECLAIM | __GFP_IO) +#define GFP_TEMPORARY (__GFP_RECLAIM | __GFP_IO | __GFP_FS | \ + __GFP_RECLAIMABLE) +#define GFP_USER (__GFP_RECLAIM | __GFP_IO | __GFP_FS | __GFP_HARDWALL) +#define GFP_DMA __GFP_DMA +#define GFP_DMA32 __GFP_DMA32 +#define GFP_HIGHUSER (GFP_USER | __GFP_HIGHMEM) +#define GFP_HIGHUSER_MOVABLE (GFP_HIGHUSER | __GFP_MOVABLE) +#define GFP_TRANSHUGE ((GFP_HIGHUSER_MOVABLE | __GFP_COMP | \ + __GFP_NOMEMALLOC | __GFP_NORETRY | __GFP_NOWARN) & \ + ~__GFP_KSWAPD_RECLAIM) + +/* Convert GFP flags to their corresponding migrate type */ +#define GFP_MOVABLE_MASK (__GFP_RECLAIMABLE|__GFP_MOVABLE) +#define GFP_MOVABLE_SHIFT 3 + +static inline int gfpflags_to_migratetype(const gfp_t gfp_flags) +{ + VM_WARN_ON((gfp_flags & GFP_MOVABLE_MASK) == GFP_MOVABLE_MASK); + BUILD_BUG_ON((1UL << GFP_MOVABLE_SHIFT) != ___GFP_MOVABLE); + BUILD_BUG_ON((___GFP_MOVABLE >> GFP_MOVABLE_SHIFT) != MIGRATE_MOVABLE); + + if (unlikely(page_group_by_mobility_disabled)) + return MIGRATE_UNMOVABLE; + + /* Group based on mobility */ +#ifndef CONFIG_CMA + return (gfp_flags & GFP_MOVABLE_MASK) >> GFP_MOVABLE_SHIFT; +#else + return ((gfp_flags & GFP_MOVABLE_MASK) >> GFP_MOVABLE_SHIFT) | + ((gfp_flags & __GFP_CMA) != 0); +#endif +} +#undef GFP_MOVABLE_MASK +#undef GFP_MOVABLE_SHIFT + +static inline bool gfpflags_allow_blocking(const gfp_t gfp_flags) +{ + return (bool __force)(gfp_flags & __GFP_DIRECT_RECLAIM); +} + +/** + * gfpflags_normal_context - is gfp_flags a normal sleepable context? + * @gfp_flags: gfp_flags to test + * + * Test whether @gfp_flags indicates that the allocation is from the + * %current context and allowed to sleep. + * + * An allocation being allowed to block doesn't mean it owns the %current + * context. When direct reclaim path tries to allocate memory, the + * allocation context is nested inside whatever %current was doing at the + * time of the original allocation. The nested allocation may be allowed + * to block but modifying anything %current owns can corrupt the outer + * context's expectations. + * + * %true result from this function indicates that the allocation context + * can sleep and use anything that's associated with %current. + */ +static inline bool gfpflags_normal_context(const gfp_t gfp_flags) +{ + return (gfp_flags & (__GFP_DIRECT_RECLAIM | __GFP_MEMALLOC)) == + __GFP_DIRECT_RECLAIM; +} + +#ifdef CONFIG_HIGHMEM +#define OPT_ZONE_HIGHMEM ZONE_HIGHMEM +#else +#define OPT_ZONE_HIGHMEM ZONE_NORMAL +#endif + +#ifdef CONFIG_ZONE_DMA +#define OPT_ZONE_DMA ZONE_DMA +#else +#define OPT_ZONE_DMA ZONE_NORMAL +#endif + +#ifdef CONFIG_ZONE_DMA32 +#define OPT_ZONE_DMA32 ZONE_DMA32 +#else +#define OPT_ZONE_DMA32 ZONE_NORMAL +#endif + +/* + * 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 1 bit of the lowest 3 bits (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+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 combinations 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 = (__force int) (flags & GFP_ZONEMASK); + + z = (GFP_ZONE_TABLE >> (bit * ZONES_SHIFT)) & + ((1 << ZONES_SHIFT) - 1); + VM_BUG_ON((GFP_ZONE_BAD >> bit) & 1); + return z; +} + +/* + * There is only one page-allocator function, and two main namespaces to + * it. The alloc_page*() variants return 'struct page *' and as such + * can allocate highmem pages, the *get*page*() variants return + * virtual kernel addresses to the allocated page(s). + */ + +static inline int gfp_zonelist(gfp_t flags) +{ + if (IS_ENABLED(CONFIG_NUMA) && unlikely(flags & __GFP_THISNODE)) + return 1; + + return 0; +} + +/* + * We get the zone list from the current node and the gfp_mask. + * This zone list contains a maximum of MAXNODES*MAX_NR_ZONES zones. + * There are two zonelists per node, one for all zones with memory and + * one containing just zones from the node the zonelist belongs to. + * + * For the normal case of non-DISCONTIGMEM systems the NODE_DATA() gets + * optimized to &contig_page_data at compile-time. + */ +static inline struct zonelist *node_zonelist(int nid, gfp_t flags) +{ + return NODE_DATA(nid)->node_zonelists + gfp_zonelist(flags); +} + +#ifndef HAVE_ARCH_FREE_PAGE +static inline void arch_free_page(struct page *page, int order) { } +#endif +#ifndef HAVE_ARCH_ALLOC_PAGE +static inline void arch_alloc_page(struct page *page, int order) { } +#endif + +struct page * +__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_nodemask(gfp_mask, order, zonelist, NULL); +} + +/* + * Allocate pages, preferring the node given as nid. The node must be valid and + * online. For more general interface, see alloc_pages_node(). + */ +static inline struct page * +__alloc_pages_node(int nid, gfp_t gfp_mask, unsigned int order) +{ + VM_BUG_ON(nid < 0 || nid >= MAX_NUMNODES); + VM_WARN_ON(!node_online(nid)); + + return __alloc_pages(gfp_mask, order, node_zonelist(nid, gfp_mask)); +} + +/* + * Allocate pages, preferring the node given as nid. When nid == NUMA_NO_NODE, + * prefer the current CPU's closest node. Otherwise node must be valid and + * online. + */ +static inline struct page *alloc_pages_node(int nid, gfp_t gfp_mask, + unsigned int order) +{ + if (nid == NUMA_NO_NODE) + nid = numa_mem_id(); + + return __alloc_pages_node(nid, gfp_mask, order); +} + +#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) +{ + return alloc_pages_current(gfp_mask, order); +} +extern struct page *alloc_pages_vma(gfp_t gfp_mask, int order, + struct vm_area_struct *vma, unsigned long addr, + int node, bool hugepage); +#define alloc_hugepage_vma(gfp_mask, vma, addr, order) \ + alloc_pages_vma(gfp_mask, order, vma, addr, numa_node_id(), true) +#else +#define alloc_pages(gfp_mask, order) \ + alloc_pages_node(numa_node_id(), gfp_mask, order) +#define alloc_pages_vma(gfp_mask, order, vma, addr, node, false)\ + alloc_pages(gfp_mask, order) +#define alloc_hugepage_vma(gfp_mask, vma, addr, order) \ + alloc_pages(gfp_mask, order) +#endif +#define alloc_page(gfp_mask) alloc_pages(gfp_mask, 0) +#define alloc_page_vma(gfp_mask, vma, addr) \ + alloc_pages_vma(gfp_mask, 0, vma, addr, numa_node_id(), false) +#define alloc_page_vma_node(gfp_mask, vma, addr, node) \ + alloc_pages_vma(gfp_mask, 0, vma, addr, node, false) + +extern struct page *alloc_kmem_pages(gfp_t gfp_mask, unsigned int order); +extern struct page *alloc_kmem_pages_node(int nid, gfp_t gfp_mask, + unsigned int order); + +extern unsigned long __get_free_pages(gfp_t gfp_mask, unsigned int order); +extern unsigned long get_zeroed_page(gfp_t gfp_mask); + +void *alloc_pages_exact(size_t size, gfp_t gfp_mask); +void free_pages_exact(void *virt, size_t size); +void * __meminit alloc_pages_exact_nid(int nid, size_t size, gfp_t gfp_mask); + +#define __get_free_page(gfp_mask) \ + __get_free_pages((gfp_mask), 0) + +#define __get_dma_pages(gfp_mask, order) \ + __get_free_pages((gfp_mask) | GFP_DMA, (order)) + +extern void __free_pages(struct page *page, unsigned int order); +extern void free_pages(unsigned long addr, unsigned int order); +extern void free_hot_cold_page(struct page *page, bool cold); +extern void free_hot_cold_page_list(struct list_head *list, bool cold); + +struct page_frag_cache; +extern void *__alloc_page_frag(struct page_frag_cache *nc, + unsigned int fragsz, gfp_t gfp_mask); +extern void __free_page_frag(void *addr); + +extern void __free_kmem_pages(struct page *page, unsigned int order); +extern void free_kmem_pages(unsigned long addr, unsigned int order); + +#define __free_page(page) __free_pages((page), 0) +#define free_page(addr) free_pages((addr), 0) + +void page_alloc_init(void); +void drain_zone_pages(struct zone *zone, struct per_cpu_pages *pcp); +void drain_all_pages(struct zone *zone); +void drain_local_pages(struct zone *zone); + +#ifdef CONFIG_DEFERRED_STRUCT_PAGE_INIT +void page_alloc_init_late(void); +#else +static inline void page_alloc_init_late(void) +{ +} +#endif + +/* + * gfp_allowed_mask is set to GFP_BOOT_MASK during early boot to restrict what + * GFP flags are used before interrupts are enabled. Once interrupts are + * enabled, it is set to __GFP_BITS_MASK while the system is running. During + * hibernation, it is used by PM to avoid I/O during memory allocation while + * devices are suspended. + */ +extern gfp_t gfp_allowed_mask; + +/* Returns true if the gfp_mask allows use of ALLOC_NO_WATERMARK */ +bool gfp_pfmemalloc_allowed(gfp_t gfp_mask); + +extern void pm_restrict_gfp_mask(void); +extern void pm_restore_gfp_mask(void); + +#ifdef CONFIG_PM_SLEEP +extern bool pm_suspended_storage(void); +#else +static inline bool pm_suspended_storage(void) +{ + return false; +} +#endif /* CONFIG_PM_SLEEP */ + +#ifdef CONFIG_CMA + +/* The below functions must be run on a range from a single zone. */ +extern int alloc_contig_range(unsigned long start, unsigned long end, + unsigned migratetype); +extern void free_contig_range(unsigned long pfn, unsigned nr_pages); + +/* CMA stuff */ +extern void init_cma_reserved_pageblock(struct page *page); + +#endif + +#endif /* __LINUX_GFP_H */ |