forked from KolibriOS/kolibrios
349 lines
14 KiB
C
349 lines
14 KiB
C
#ifndef __LINUX_GFP_H
|
|
#define __LINUX_GFP_H
|
|
|
|
#include <linux/mmdebug.h>
|
|
#include <linux/types.h>
|
|
#include <linux/stddef.h>
|
|
#include <linux/linkage.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
|
|
/* 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_ZONEMASK (__GFP_DMA|__GFP_HIGHMEM|__GFP_DMA32|__GFP_MOVABLE)
|
|
|
|
/*
|
|
* 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 26
|
|
#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
|
|
|
|
#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);
|
|
}
|
|
|
|
#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) \
|
|
)
|
|
|
|
|
|
#endif /* __LINUX_GFP_H */
|