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-rw-r--r--include/linux/gfp.h623
1 files changed, 623 insertions, 0 deletions
diff --git a/include/linux/gfp.h b/include/linux/gfp.h
new file mode 100644
index 000000000..f78d1e895
--- /dev/null
+++ b/include/linux/gfp.h
@@ -0,0 +1,623 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+#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;
+
+/*
+ * In case of changes, please don't forget to update
+ * include/trace/events/mmflags.h and tools/perf/builtin-kmem.c
+ */
+
+/* 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_WRITE 0x100u
+#define ___GFP_NOWARN 0x200u
+#define ___GFP_RETRY_MAYFAIL 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_ACCOUNT 0x100000u
+#define ___GFP_DIRECT_RECLAIM 0x200000u
+#define ___GFP_KSWAPD_RECLAIM 0x400000u
+#ifdef CONFIG_LOCKDEP
+#define ___GFP_NOLOCKDEP 0x800000u
+#else
+#define ___GFP_NOLOCKDEP 0
+#endif
+/* 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) /* ZONE_MOVABLE allowed */
+#define GFP_ZONEMASK (__GFP_DMA|__GFP_HIGHMEM|__GFP_DMA32|__GFP_MOVABLE)
+
+/**
+ * DOC: Page mobility and placement hints
+ *
+ * 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.
+ *
+ * %__GFP_ACCOUNT causes the allocation to be accounted to kmemcg.
+ */
+#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)
+#define __GFP_ACCOUNT ((__force gfp_t)___GFP_ACCOUNT)
+
+/**
+ * DOC: Watermark modifiers
+ *
+ * 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.
+ */
+#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)
+
+/**
+ * DOC: Reclaim modifiers
+ *
+ * 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.
+ *
+ * The default allocator behavior depends on the request size. We have a concept
+ * of so called costly allocations (with order > %PAGE_ALLOC_COSTLY_ORDER).
+ * !costly allocations are too essential to fail so they are implicitly
+ * non-failing by default (with some exceptions like OOM victims might fail so
+ * the caller still has to check for failures) while costly requests try to be
+ * not disruptive and back off even without invoking the OOM killer.
+ * The following three modifiers might be used to override some of these
+ * implicit rules
+ *
+ * %__GFP_NORETRY: The VM implementation will try only very lightweight
+ * memory direct reclaim to get some memory under memory pressure (thus
+ * it can sleep). It will avoid disruptive actions like OOM killer. The
+ * caller must handle the failure which is quite likely to happen under
+ * heavy memory pressure. The flag is suitable when failure can easily be
+ * handled at small cost, such as reduced throughput
+ *
+ * %__GFP_RETRY_MAYFAIL: The VM implementation will retry memory reclaim
+ * procedures that have previously failed if there is some indication
+ * that progress has been made else where. It can wait for other
+ * tasks to attempt high level approaches to freeing memory such as
+ * compaction (which removes fragmentation) and page-out.
+ * There is still a definite limit to the number of retries, but it is
+ * a larger limit than with %__GFP_NORETRY.
+ * Allocations with this flag may fail, but only when there is
+ * genuinely little unused memory. While these allocations do not
+ * directly trigger the OOM killer, their failure indicates that
+ * the system is likely to need to use the OOM killer soon. The
+ * caller must handle failure, but can reasonably do so by failing
+ * a higher-level request, or completing it only in a much less
+ * efficient manner.
+ * If the allocation does fail, and the caller is in a position to
+ * free some non-essential memory, doing so could benefit the system
+ * as a whole.
+ *
+ * %__GFP_NOFAIL: The VM implementation _must_ retry infinitely: the caller
+ * cannot handle allocation failures. The allocation could block
+ * indefinitely but will never return with failure. Testing for
+ * failure is pointless.
+ * 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.
+ * Using this flag for costly allocations is _highly_ discouraged.
+ */
+#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_RETRY_MAYFAIL ((__force gfp_t)___GFP_RETRY_MAYFAIL)
+#define __GFP_NOFAIL ((__force gfp_t)___GFP_NOFAIL)
+#define __GFP_NORETRY ((__force gfp_t)___GFP_NORETRY)
+
+/**
+ * DOC: Action modifiers
+ *
+ * Action modifiers
+ * ~~~~~~~~~~~~~~~~
+ *
+ * %__GFP_NOWARN suppresses allocation failure reports.
+ *
+ * %__GFP_COMP address compound page metadata.
+ *
+ * %__GFP_ZERO returns a zeroed page on success.
+ */
+#define __GFP_NOWARN ((__force gfp_t)___GFP_NOWARN)
+#define __GFP_COMP ((__force gfp_t)___GFP_COMP)
+#define __GFP_ZERO ((__force gfp_t)___GFP_ZERO)
+
+/* Disable lockdep for GFP context tracking */
+#define __GFP_NOLOCKDEP ((__force gfp_t)___GFP_NOLOCKDEP)
+
+/* Room for N __GFP_FOO bits */
+#define __GFP_BITS_SHIFT (23 + IS_ENABLED(CONFIG_LOCKDEP))
+#define __GFP_BITS_MASK ((__force gfp_t)((1 << __GFP_BITS_SHIFT) - 1))
+
+/**
+ * DOC: Useful GFP flag combinations
+ *
+ * Useful GFP flag combinations
+ * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+ *
+ * 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_KERNEL_ACCOUNT is the same as GFP_KERNEL, except the allocation is
+ * accounted to kmemcg.
+ *
+ * %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.
+ * Please try to avoid using this flag directly and instead use
+ * memalloc_noio_{save,restore} to mark the whole scope which cannot
+ * perform any IO with a short explanation why. All allocation requests
+ * will inherit GFP_NOIO implicitly.
+ *
+ * %GFP_NOFS will use direct reclaim but will not use any filesystem interfaces.
+ * Please try to avoid using this flag directly and instead use
+ * memalloc_nofs_{save,restore} to mark the whole scope which cannot/shouldn't
+ * recurse into the FS layer with a short explanation why. All allocation
+ * requests will inherit GFP_NOFS implicitly.
+ *
+ * %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 and %GFP_TRANSHUGE_LIGHT are used for THP allocations. They
+ * are compound allocations that will generally fail quickly if memory is not
+ * available and will not wake kswapd/kcompactd on failure. The _LIGHT
+ * version does not attempt reclaim/compaction at all and is by default used
+ * in page fault path, while the non-light is used by khugepaged.
+ */
+#define GFP_ATOMIC (__GFP_HIGH|__GFP_ATOMIC|__GFP_KSWAPD_RECLAIM)
+#define GFP_KERNEL (__GFP_RECLAIM | __GFP_IO | __GFP_FS)
+#define GFP_KERNEL_ACCOUNT (GFP_KERNEL | __GFP_ACCOUNT)
+#define GFP_NOWAIT (__GFP_KSWAPD_RECLAIM)
+#define GFP_NOIO (__GFP_RECLAIM)
+#define GFP_NOFS (__GFP_RECLAIM | __GFP_IO)
+#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_LIGHT ((GFP_HIGHUSER_MOVABLE | __GFP_COMP | \
+ __GFP_NOMEMALLOC | __GFP_NOWARN) & ~__GFP_RECLAIM)
+#define GFP_TRANSHUGE (GFP_TRANSHUGE_LIGHT | __GFP_DIRECT_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 */
+ return (gfp_flags & GFP_MOVABLE_MASK) >> GFP_MOVABLE_SHIFT;
+}
+#undef GFP_MOVABLE_MASK
+#undef GFP_MOVABLE_SHIFT
+
+static inline bool gfpflags_allow_blocking(const gfp_t gfp_flags)
+{
+ return !!(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 GFP_ZONES_SHIFT
+ * bits 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 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 or NORMAL (MOVABLE+DMA32)
+ * 0xd => BAD (MOVABLE+DMA32+DMA)
+ * 0xe => BAD (MOVABLE+DMA32+HIGHMEM)
+ * 0xf => BAD (MOVABLE+DMA32+HIGHMEM+DMA)
+ *
+ * GFP_ZONES_SHIFT must be <= 2 on 32 bit platforms.
+ */
+
+#if defined(CONFIG_ZONE_DEVICE) && (MAX_NR_ZONES-1) <= 4
+/* ZONE_DEVICE is not a valid GFP zone specifier */
+#define GFP_ZONES_SHIFT 2
+#else
+#define GFP_ZONES_SHIFT ZONES_SHIFT
+#endif
+
+#if 16 * GFP_ZONES_SHIFT > BITS_PER_LONG
+#error GFP_ZONES_SHIFT too large to create GFP_ZONE_TABLE integer
+#endif
+
+#define GFP_ZONE_TABLE ( \
+ (ZONE_NORMAL << 0 * GFP_ZONES_SHIFT) \
+ | (OPT_ZONE_DMA << ___GFP_DMA * GFP_ZONES_SHIFT) \
+ | (OPT_ZONE_HIGHMEM << ___GFP_HIGHMEM * GFP_ZONES_SHIFT) \
+ | (OPT_ZONE_DMA32 << ___GFP_DMA32 * GFP_ZONES_SHIFT) \
+ | (ZONE_NORMAL << ___GFP_MOVABLE * GFP_ZONES_SHIFT) \
+ | (OPT_ZONE_DMA << (___GFP_MOVABLE | ___GFP_DMA) * GFP_ZONES_SHIFT) \
+ | (ZONE_MOVABLE << (___GFP_MOVABLE | ___GFP_HIGHMEM) * GFP_ZONES_SHIFT)\
+ | (OPT_ZONE_DMA32 << (___GFP_MOVABLE | ___GFP_DMA32) * GFP_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 * GFP_ZONES_SHIFT)) &
+ ((1 << GFP_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)
+{
+#ifdef CONFIG_NUMA
+ if (unlikely(flags & __GFP_THISNODE))
+ return ZONELIST_NOFALLBACK;
+#endif
+ return ZONELIST_FALLBACK;
+}
+
+/*
+ * 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, int preferred_nid,
+ nodemask_t *nodemask);
+
+static inline struct page *
+__alloc_pages(gfp_t gfp_mask, unsigned int order, int preferred_nid)
+{
+ return __alloc_pages_nodemask(gfp_mask, order, preferred_nid, 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((gfp_mask & __GFP_THISNODE) && !node_online(nid));
+
+ return __alloc_pages(gfp_mask, order, nid);
+}
+
+/*
+ * 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 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_unref_page(struct page *page);
+extern void free_unref_page_list(struct list_head *list);
+
+struct page_frag_cache;
+extern void __page_frag_cache_drain(struct page *page, unsigned int count);
+extern void *page_frag_alloc(struct page_frag_cache *nc,
+ unsigned int fragsz, gfp_t gfp_mask);
+extern void page_frag_free(void *addr);
+
+#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);
+
+void page_alloc_init_late(void);
+
+/*
+ * 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 */
+
+#if (defined(CONFIG_MEMORY_ISOLATION) && defined(CONFIG_COMPACTION)) || defined(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, gfp_t gfp_mask);
+extern void free_contig_range(unsigned long pfn, unsigned nr_pages);
+#endif
+
+#ifdef CONFIG_CMA
+/* CMA stuff */
+extern void init_cma_reserved_pageblock(struct page *page);
+#endif
+
+#endif /* __LINUX_GFP_H */