1/* SPDX-License-Identifier: GPL-2.0 */ 2#ifndef __LINUX_GFP_H 3#define __LINUX_GFP_H 4 5#include <linux/mmdebug.h> 6#include <linux/mmzone.h> 7#include <linux/stddef.h> 8#include <linux/linkage.h> 9#include <linux/topology.h> 10 11/* The typedef is in types.h but we want the documentation here */ 12#if 0 13/** 14 * typedef gfp_t - Memory allocation flags. 15 * 16 * GFP flags are commonly used throughout Linux to indicate how memory 17 * should be allocated. The GFP acronym stands for get_free_pages(), 18 * the underlying memory allocation function. Not every GFP flag is 19 * supported by every function which may allocate memory. Most users 20 * will want to use a plain ``GFP_KERNEL``. 21 */ 22typedef unsigned int __bitwise gfp_t; 23#endif 24 25struct vm_area_struct; 26 27/* 28 * In case of changes, please don't forget to update 29 * include/trace/events/mmflags.h and tools/perf/builtin-kmem.c 30 */ 31 32/* Plain integer GFP bitmasks. Do not use this directly. */ 33#define ___GFP_DMA 0x01u 34#define ___GFP_HIGHMEM 0x02u 35#define ___GFP_DMA32 0x04u 36#define ___GFP_MOVABLE 0x08u 37#define ___GFP_RECLAIMABLE 0x10u 38#define ___GFP_HIGH 0x20u 39#define ___GFP_IO 0x40u 40#define ___GFP_FS 0x80u 41#define ___GFP_ZERO 0x100u 42#define ___GFP_ATOMIC 0x200u 43#define ___GFP_DIRECT_RECLAIM 0x400u 44#define ___GFP_KSWAPD_RECLAIM 0x800u 45#define ___GFP_WRITE 0x1000u 46#define ___GFP_NOWARN 0x2000u 47#define ___GFP_RETRY_MAYFAIL 0x4000u 48#define ___GFP_NOFAIL 0x8000u 49#define ___GFP_NORETRY 0x10000u 50#define ___GFP_MEMALLOC 0x20000u 51#define ___GFP_COMP 0x40000u 52#define ___GFP_NOMEMALLOC 0x80000u 53#define ___GFP_HARDWALL 0x100000u 54#define ___GFP_THISNODE 0x200000u 55#define ___GFP_ACCOUNT 0x400000u 56#define ___GFP_ZEROTAGS 0x800000u 57#define ___GFP_SKIP_KASAN_POISON 0x1000000u 58#ifdef CONFIG_LOCKDEP 59#define ___GFP_NOLOCKDEP 0x2000000u 60#else 61#define ___GFP_NOLOCKDEP 0 62#endif 63/* If the above are modified, __GFP_BITS_SHIFT may need updating */ 64 65/* 66 * Physical address zone modifiers (see linux/mmzone.h - low four bits) 67 * 68 * Do not put any conditional on these. If necessary modify the definitions 69 * without the underscores and use them consistently. The definitions here may 70 * be used in bit comparisons. 71 */ 72#define __GFP_DMA ((__force gfp_t)___GFP_DMA) 73#define __GFP_HIGHMEM ((__force gfp_t)___GFP_HIGHMEM) 74#define __GFP_DMA32 ((__force gfp_t)___GFP_DMA32) 75#define __GFP_MOVABLE ((__force gfp_t)___GFP_MOVABLE) /* ZONE_MOVABLE allowed */ 76#define GFP_ZONEMASK (__GFP_DMA|__GFP_HIGHMEM|__GFP_DMA32|__GFP_MOVABLE) 77 78/** 79 * DOC: Page mobility and placement hints 80 * 81 * Page mobility and placement hints 82 * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ 83 * 84 * These flags provide hints about how mobile the page is. Pages with similar 85 * mobility are placed within the same pageblocks to minimise problems due 86 * to external fragmentation. 87 * 88 * %__GFP_MOVABLE (also a zone modifier) indicates that the page can be 89 * moved by page migration during memory compaction or can be reclaimed. 90 * 91 * %__GFP_RECLAIMABLE is used for slab allocations that specify 92 * SLAB_RECLAIM_ACCOUNT and whose pages can be freed via shrinkers. 93 * 94 * %__GFP_WRITE indicates the caller intends to dirty the page. Where possible, 95 * these pages will be spread between local zones to avoid all the dirty 96 * pages being in one zone (fair zone allocation policy). 97 * 98 * %__GFP_HARDWALL enforces the cpuset memory allocation policy. 99 * 100 * %__GFP_THISNODE forces the allocation to be satisfied from the requested 101 * node with no fallbacks or placement policy enforcements. 102 * 103 * %__GFP_ACCOUNT causes the allocation to be accounted to kmemcg. 104 */ 105#define __GFP_RECLAIMABLE ((__force gfp_t)___GFP_RECLAIMABLE) 106#define __GFP_WRITE ((__force gfp_t)___GFP_WRITE) 107#define __GFP_HARDWALL ((__force gfp_t)___GFP_HARDWALL) 108#define __GFP_THISNODE ((__force gfp_t)___GFP_THISNODE) 109#define __GFP_ACCOUNT ((__force gfp_t)___GFP_ACCOUNT) 110 111/** 112 * DOC: Watermark modifiers 113 * 114 * Watermark modifiers -- controls access to emergency reserves 115 * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ 116 * 117 * %__GFP_HIGH indicates that the caller is high-priority and that granting 118 * the request is necessary before the system can make forward progress. 119 * For example, creating an IO context to clean pages. 120 * 121 * %__GFP_ATOMIC indicates that the caller cannot reclaim or sleep and is 122 * high priority. Users are typically interrupt handlers. This may be 123 * used in conjunction with %__GFP_HIGH 124 * 125 * %__GFP_MEMALLOC allows access to all memory. This should only be used when 126 * the caller guarantees the allocation will allow more memory to be freed 127 * very shortly e.g. process exiting or swapping. Users either should 128 * be the MM or co-ordinating closely with the VM (e.g. swap over NFS). 129 * Users of this flag have to be extremely careful to not deplete the reserve 130 * completely and implement a throttling mechanism which controls the 131 * consumption of the reserve based on the amount of freed memory. 132 * Usage of a pre-allocated pool (e.g. mempool) should be always considered 133 * before using this flag. 134 * 135 * %__GFP_NOMEMALLOC is used to explicitly forbid access to emergency reserves. 136 * This takes precedence over the %__GFP_MEMALLOC flag if both are set. 137 */ 138#define __GFP_ATOMIC ((__force gfp_t)___GFP_ATOMIC) 139#define __GFP_HIGH ((__force gfp_t)___GFP_HIGH) 140#define __GFP_MEMALLOC ((__force gfp_t)___GFP_MEMALLOC) 141#define __GFP_NOMEMALLOC ((__force gfp_t)___GFP_NOMEMALLOC) 142 143/** 144 * DOC: Reclaim modifiers 145 * 146 * Reclaim modifiers 147 * ~~~~~~~~~~~~~~~~~ 148 * Please note that all the following flags are only applicable to sleepable 149 * allocations (e.g. %GFP_NOWAIT and %GFP_ATOMIC will ignore them). 150 * 151 * %__GFP_IO can start physical IO. 152 * 153 * %__GFP_FS can call down to the low-level FS. Clearing the flag avoids the 154 * allocator recursing into the filesystem which might already be holding 155 * locks. 156 * 157 * %__GFP_DIRECT_RECLAIM indicates that the caller may enter direct reclaim. 158 * This flag can be cleared to avoid unnecessary delays when a fallback 159 * option is available. 160 * 161 * %__GFP_KSWAPD_RECLAIM indicates that the caller wants to wake kswapd when 162 * the low watermark is reached and have it reclaim pages until the high 163 * watermark is reached. A caller may wish to clear this flag when fallback 164 * options are available and the reclaim is likely to disrupt the system. The 165 * canonical example is THP allocation where a fallback is cheap but 166 * reclaim/compaction may cause indirect stalls. 167 * 168 * %__GFP_RECLAIM is shorthand to allow/forbid both direct and kswapd reclaim. 169 * 170 * The default allocator behavior depends on the request size. We have a concept 171 * of so called costly allocations (with order > %PAGE_ALLOC_COSTLY_ORDER). 172 * !costly allocations are too essential to fail so they are implicitly 173 * non-failing by default (with some exceptions like OOM victims might fail so 174 * the caller still has to check for failures) while costly requests try to be 175 * not disruptive and back off even without invoking the OOM killer. 176 * The following three modifiers might be used to override some of these 177 * implicit rules 178 * 179 * %__GFP_NORETRY: The VM implementation will try only very lightweight 180 * memory direct reclaim to get some memory under memory pressure (thus 181 * it can sleep). It will avoid disruptive actions like OOM killer. The 182 * caller must handle the failure which is quite likely to happen under 183 * heavy memory pressure. The flag is suitable when failure can easily be 184 * handled at small cost, such as reduced throughput 185 * 186 * %__GFP_RETRY_MAYFAIL: The VM implementation will retry memory reclaim 187 * procedures that have previously failed if there is some indication 188 * that progress has been made else where. It can wait for other 189 * tasks to attempt high level approaches to freeing memory such as 190 * compaction (which removes fragmentation) and page-out. 191 * There is still a definite limit to the number of retries, but it is 192 * a larger limit than with %__GFP_NORETRY. 193 * Allocations with this flag may fail, but only when there is 194 * genuinely little unused memory. While these allocations do not 195 * directly trigger the OOM killer, their failure indicates that 196 * the system is likely to need to use the OOM killer soon. The 197 * caller must handle failure, but can reasonably do so by failing 198 * a higher-level request, or completing it only in a much less 199 * efficient manner. 200 * If the allocation does fail, and the caller is in a position to 201 * free some non-essential memory, doing so could benefit the system 202 * as a whole. 203 * 204 * %__GFP_NOFAIL: The VM implementation _must_ retry infinitely: the caller 205 * cannot handle allocation failures. The allocation could block 206 * indefinitely but will never return with failure. Testing for 207 * failure is pointless. 208 * New users should be evaluated carefully (and the flag should be 209 * used only when there is no reasonable failure policy) but it is 210 * definitely preferable to use the flag rather than opencode endless 211 * loop around allocator. 212 * Using this flag for costly allocations is _highly_ discouraged. 213 */ 214#define __GFP_IO ((__force gfp_t)___GFP_IO) 215#define __GFP_FS ((__force gfp_t)___GFP_FS) 216#define __GFP_DIRECT_RECLAIM ((__force gfp_t)___GFP_DIRECT_RECLAIM) /* Caller can reclaim */ 217#define __GFP_KSWAPD_RECLAIM ((__force gfp_t)___GFP_KSWAPD_RECLAIM) /* kswapd can wake */ 218#define __GFP_RECLAIM ((__force gfp_t)(___GFP_DIRECT_RECLAIM|___GFP_KSWAPD_RECLAIM)) 219#define __GFP_RETRY_MAYFAIL ((__force gfp_t)___GFP_RETRY_MAYFAIL) 220#define __GFP_NOFAIL ((__force gfp_t)___GFP_NOFAIL) 221#define __GFP_NORETRY ((__force gfp_t)___GFP_NORETRY) 222 223/** 224 * DOC: Action modifiers 225 * 226 * Action modifiers 227 * ~~~~~~~~~~~~~~~~ 228 * 229 * %__GFP_NOWARN suppresses allocation failure reports. 230 * 231 * %__GFP_COMP address compound page metadata. 232 * 233 * %__GFP_ZERO returns a zeroed page on success. 234 * 235 * %__GFP_ZEROTAGS returns a page with zeroed memory tags on success, if 236 * __GFP_ZERO is set. 237 * 238 * %__GFP_SKIP_KASAN_POISON returns a page which does not need to be poisoned 239 * on deallocation. Typically used for userspace pages. Currently only has an 240 * effect in HW tags mode. 241 */ 242#define __GFP_NOWARN ((__force gfp_t)___GFP_NOWARN) 243#define __GFP_COMP ((__force gfp_t)___GFP_COMP) 244#define __GFP_ZERO ((__force gfp_t)___GFP_ZERO) 245#define __GFP_ZEROTAGS ((__force gfp_t)___GFP_ZEROTAGS) 246#define __GFP_SKIP_KASAN_POISON ((__force gfp_t)___GFP_SKIP_KASAN_POISON) 247 248/* Disable lockdep for GFP context tracking */ 249#define __GFP_NOLOCKDEP ((__force gfp_t)___GFP_NOLOCKDEP) 250 251/* Room for N __GFP_FOO bits */ 252#define __GFP_BITS_SHIFT (25 + IS_ENABLED(CONFIG_LOCKDEP)) 253#define __GFP_BITS_MASK ((__force gfp_t)((1 << __GFP_BITS_SHIFT) - 1)) 254 255/** 256 * DOC: Useful GFP flag combinations 257 * 258 * Useful GFP flag combinations 259 * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~ 260 * 261 * Useful GFP flag combinations that are commonly used. It is recommended 262 * that subsystems start with one of these combinations and then set/clear 263 * %__GFP_FOO flags as necessary. 264 * 265 * %GFP_ATOMIC users can not sleep and need the allocation to succeed. A lower 266 * watermark is applied to allow access to "atomic reserves". 267 * The current implementation doesn't support NMI and few other strict 268 * non-preemptive contexts (e.g. raw_spin_lock). The same applies to %GFP_NOWAIT. 269 * 270 * %GFP_KERNEL is typical for kernel-internal allocations. The caller requires 271 * %ZONE_NORMAL or a lower zone for direct access but can direct reclaim. 272 * 273 * %GFP_KERNEL_ACCOUNT is the same as GFP_KERNEL, except the allocation is 274 * accounted to kmemcg. 275 * 276 * %GFP_NOWAIT is for kernel allocations that should not stall for direct 277 * reclaim, start physical IO or use any filesystem callback. 278 * 279 * %GFP_NOIO will use direct reclaim to discard clean pages or slab pages 280 * that do not require the starting of any physical IO. 281 * Please try to avoid using this flag directly and instead use 282 * memalloc_noio_{save,restore} to mark the whole scope which cannot 283 * perform any IO with a short explanation why. All allocation requests 284 * will inherit GFP_NOIO implicitly. 285 * 286 * %GFP_NOFS will use direct reclaim but will not use any filesystem interfaces. 287 * Please try to avoid using this flag directly and instead use 288 * memalloc_nofs_{save,restore} to mark the whole scope which cannot/shouldn't 289 * recurse into the FS layer with a short explanation why. All allocation 290 * requests will inherit GFP_NOFS implicitly. 291 * 292 * %GFP_USER is for userspace allocations that also need to be directly 293 * accessibly by the kernel or hardware. It is typically used by hardware 294 * for buffers that are mapped to userspace (e.g. graphics) that hardware 295 * still must DMA to. cpuset limits are enforced for these allocations. 296 * 297 * %GFP_DMA exists for historical reasons and should be avoided where possible. 298 * The flags indicates that the caller requires that the lowest zone be 299 * used (%ZONE_DMA or 16M on x86-64). Ideally, this would be removed but 300 * it would require careful auditing as some users really require it and 301 * others use the flag to avoid lowmem reserves in %ZONE_DMA and treat the 302 * lowest zone as a type of emergency reserve. 303 * 304 * %GFP_DMA32 is similar to %GFP_DMA except that the caller requires a 32-bit 305 * address. 306 * 307 * %GFP_HIGHUSER is for userspace allocations that may be mapped to userspace, 308 * do not need to be directly accessible by the kernel but that cannot 309 * move once in use. An example may be a hardware allocation that maps 310 * data directly into userspace but has no addressing limitations. 311 * 312 * %GFP_HIGHUSER_MOVABLE is for userspace allocations that the kernel does not 313 * need direct access to but can use kmap() when access is required. They 314 * are expected to be movable via page reclaim or page migration. Typically, 315 * pages on the LRU would also be allocated with %GFP_HIGHUSER_MOVABLE. 316 * 317 * %GFP_TRANSHUGE and %GFP_TRANSHUGE_LIGHT are used for THP allocations. They 318 * are compound allocations that will generally fail quickly if memory is not 319 * available and will not wake kswapd/kcompactd on failure. The _LIGHT 320 * version does not attempt reclaim/compaction at all and is by default used 321 * in page fault path, while the non-light is used by khugepaged. 322 */ 323#define GFP_ATOMIC (__GFP_HIGH|__GFP_ATOMIC|__GFP_KSWAPD_RECLAIM) 324#define GFP_KERNEL (__GFP_RECLAIM | __GFP_IO | __GFP_FS) 325#define GFP_KERNEL_ACCOUNT (GFP_KERNEL | __GFP_ACCOUNT) 326#define GFP_NOWAIT (__GFP_KSWAPD_RECLAIM) 327#define GFP_NOIO (__GFP_RECLAIM) 328#define GFP_NOFS (__GFP_RECLAIM | __GFP_IO) 329#define GFP_USER (__GFP_RECLAIM | __GFP_IO | __GFP_FS | __GFP_HARDWALL) 330#define GFP_DMA __GFP_DMA 331#define GFP_DMA32 __GFP_DMA32 332#define GFP_HIGHUSER (GFP_USER | __GFP_HIGHMEM) 333#define GFP_HIGHUSER_MOVABLE (GFP_HIGHUSER | __GFP_MOVABLE | \ 334 __GFP_SKIP_KASAN_POISON) 335#define GFP_TRANSHUGE_LIGHT ((GFP_HIGHUSER_MOVABLE | __GFP_COMP | \ 336 __GFP_NOMEMALLOC | __GFP_NOWARN) & ~__GFP_RECLAIM) 337#define GFP_TRANSHUGE (GFP_TRANSHUGE_LIGHT | __GFP_DIRECT_RECLAIM) 338 339/* Convert GFP flags to their corresponding migrate type */ 340#define GFP_MOVABLE_MASK (__GFP_RECLAIMABLE|__GFP_MOVABLE) 341#define GFP_MOVABLE_SHIFT 3 342 343static inline int gfp_migratetype(const gfp_t gfp_flags) 344{ 345 VM_WARN_ON((gfp_flags & GFP_MOVABLE_MASK) == GFP_MOVABLE_MASK); 346 BUILD_BUG_ON((1UL << GFP_MOVABLE_SHIFT) != ___GFP_MOVABLE); 347 BUILD_BUG_ON((___GFP_MOVABLE >> GFP_MOVABLE_SHIFT) != MIGRATE_MOVABLE); 348 349 if (unlikely(page_group_by_mobility_disabled)) 350 return MIGRATE_UNMOVABLE; 351 352 /* Group based on mobility */ 353 return (gfp_flags & GFP_MOVABLE_MASK) >> GFP_MOVABLE_SHIFT; 354} 355#undef GFP_MOVABLE_MASK 356#undef GFP_MOVABLE_SHIFT 357 358static inline bool gfpflags_allow_blocking(const gfp_t gfp_flags) 359{ 360 return !!(gfp_flags & __GFP_DIRECT_RECLAIM); 361} 362 363/** 364 * gfpflags_normal_context - is gfp_flags a normal sleepable context? 365 * @gfp_flags: gfp_flags to test 366 * 367 * Test whether @gfp_flags indicates that the allocation is from the 368 * %current context and allowed to sleep. 369 * 370 * An allocation being allowed to block doesn't mean it owns the %current 371 * context. When direct reclaim path tries to allocate memory, the 372 * allocation context is nested inside whatever %current was doing at the 373 * time of the original allocation. The nested allocation may be allowed 374 * to block but modifying anything %current owns can corrupt the outer 375 * context's expectations. 376 * 377 * %true result from this function indicates that the allocation context 378 * can sleep and use anything that's associated with %current. 379 */ 380static inline bool gfpflags_normal_context(const gfp_t gfp_flags) 381{ 382 return (gfp_flags & (__GFP_DIRECT_RECLAIM | __GFP_MEMALLOC)) == 383 __GFP_DIRECT_RECLAIM; 384} 385 386#ifdef CONFIG_HIGHMEM 387#define OPT_ZONE_HIGHMEM ZONE_HIGHMEM 388#else 389#define OPT_ZONE_HIGHMEM ZONE_NORMAL 390#endif 391 392#ifdef CONFIG_ZONE_DMA 393#define OPT_ZONE_DMA ZONE_DMA 394#else 395#define OPT_ZONE_DMA ZONE_NORMAL 396#endif 397 398#ifdef CONFIG_ZONE_DMA32 399#define OPT_ZONE_DMA32 ZONE_DMA32 400#else 401#define OPT_ZONE_DMA32 ZONE_NORMAL 402#endif 403 404/* 405 * GFP_ZONE_TABLE is a word size bitstring that is used for looking up the 406 * zone to use given the lowest 4 bits of gfp_t. Entries are GFP_ZONES_SHIFT 407 * bits long and there are 16 of them to cover all possible combinations of 408 * __GFP_DMA, __GFP_DMA32, __GFP_MOVABLE and __GFP_HIGHMEM. 409 * 410 * The zone fallback order is MOVABLE=>HIGHMEM=>NORMAL=>DMA32=>DMA. 411 * But GFP_MOVABLE is not only a zone specifier but also an allocation 412 * policy. Therefore __GFP_MOVABLE plus another zone selector is valid. 413 * Only 1 bit of the lowest 3 bits (DMA,DMA32,HIGHMEM) can be set to "1". 414 * 415 * bit result 416 * ================= 417 * 0x0 => NORMAL 418 * 0x1 => DMA or NORMAL 419 * 0x2 => HIGHMEM or NORMAL 420 * 0x3 => BAD (DMA+HIGHMEM) 421 * 0x4 => DMA32 or NORMAL 422 * 0x5 => BAD (DMA+DMA32) 423 * 0x6 => BAD (HIGHMEM+DMA32) 424 * 0x7 => BAD (HIGHMEM+DMA32+DMA) 425 * 0x8 => NORMAL (MOVABLE+0) 426 * 0x9 => DMA or NORMAL (MOVABLE+DMA) 427 * 0xa => MOVABLE (Movable is valid only if HIGHMEM is set too) 428 * 0xb => BAD (MOVABLE+HIGHMEM+DMA) 429 * 0xc => DMA32 or NORMAL (MOVABLE+DMA32) 430 * 0xd => BAD (MOVABLE+DMA32+DMA) 431 * 0xe => BAD (MOVABLE+DMA32+HIGHMEM) 432 * 0xf => BAD (MOVABLE+DMA32+HIGHMEM+DMA) 433 * 434 * GFP_ZONES_SHIFT must be <= 2 on 32 bit platforms. 435 */ 436 437#if defined(CONFIG_ZONE_DEVICE) && (MAX_NR_ZONES-1) <= 4 438/* ZONE_DEVICE is not a valid GFP zone specifier */ 439#define GFP_ZONES_SHIFT 2 440#else 441#define GFP_ZONES_SHIFT ZONES_SHIFT 442#endif 443 444#if 16 * GFP_ZONES_SHIFT > BITS_PER_LONG 445#error GFP_ZONES_SHIFT too large to create GFP_ZONE_TABLE integer 446#endif 447 448#define GFP_ZONE_TABLE ( \ 449 (ZONE_NORMAL << 0 * GFP_ZONES_SHIFT) \ 450 | (OPT_ZONE_DMA << ___GFP_DMA * GFP_ZONES_SHIFT) \ 451 | (OPT_ZONE_HIGHMEM << ___GFP_HIGHMEM * GFP_ZONES_SHIFT) \ 452 | (OPT_ZONE_DMA32 << ___GFP_DMA32 * GFP_ZONES_SHIFT) \ 453 | (ZONE_NORMAL << ___GFP_MOVABLE * GFP_ZONES_SHIFT) \ 454 | (OPT_ZONE_DMA << (___GFP_MOVABLE | ___GFP_DMA) * GFP_ZONES_SHIFT) \ 455 | (ZONE_MOVABLE << (___GFP_MOVABLE | ___GFP_HIGHMEM) * GFP_ZONES_SHIFT)\ 456 | (OPT_ZONE_DMA32 << (___GFP_MOVABLE | ___GFP_DMA32) * GFP_ZONES_SHIFT)\ 457) 458 459/* 460 * GFP_ZONE_BAD is a bitmap for all combinations of __GFP_DMA, __GFP_DMA32 461 * __GFP_HIGHMEM and __GFP_MOVABLE that are not permitted. One flag per 462 * entry starting with bit 0. Bit is set if the combination is not 463 * allowed. 464 */ 465#define GFP_ZONE_BAD ( \ 466 1 << (___GFP_DMA | ___GFP_HIGHMEM) \ 467 | 1 << (___GFP_DMA | ___GFP_DMA32) \ 468 | 1 << (___GFP_DMA32 | ___GFP_HIGHMEM) \ 469 | 1 << (___GFP_DMA | ___GFP_DMA32 | ___GFP_HIGHMEM) \ 470 | 1 << (___GFP_MOVABLE | ___GFP_HIGHMEM | ___GFP_DMA) \ 471 | 1 << (___GFP_MOVABLE | ___GFP_DMA32 | ___GFP_DMA) \ 472 | 1 << (___GFP_MOVABLE | ___GFP_DMA32 | ___GFP_HIGHMEM) \ 473 | 1 << (___GFP_MOVABLE | ___GFP_DMA32 | ___GFP_DMA | ___GFP_HIGHMEM) \ 474) 475 476static inline enum zone_type gfp_zone(gfp_t flags) 477{ 478 enum zone_type z; 479 int bit = (__force int) (flags & GFP_ZONEMASK); 480 481 z = (GFP_ZONE_TABLE >> (bit * GFP_ZONES_SHIFT)) & 482 ((1 << GFP_ZONES_SHIFT) - 1); 483 VM_BUG_ON((GFP_ZONE_BAD >> bit) & 1); 484 return z; 485} 486 487/* 488 * There is only one page-allocator function, and two main namespaces to 489 * it. The alloc_page*() variants return 'struct page *' and as such 490 * can allocate highmem pages, the *get*page*() variants return 491 * virtual kernel addresses to the allocated page(s). 492 */ 493 494static inline int gfp_zonelist(gfp_t flags) 495{ 496#ifdef CONFIG_NUMA 497 if (unlikely(flags & __GFP_THISNODE)) 498 return ZONELIST_NOFALLBACK; 499#endif 500 return ZONELIST_FALLBACK; 501} 502 503/* 504 * We get the zone list from the current node and the gfp_mask. 505 * This zone list contains a maximum of MAX_NUMNODES*MAX_NR_ZONES zones. 506 * There are two zonelists per node, one for all zones with memory and 507 * one containing just zones from the node the zonelist belongs to. 508 * 509 * For the case of non-NUMA systems the NODE_DATA() gets optimized to 510 * &contig_page_data at compile-time. 511 */ 512static inline struct zonelist *node_zonelist(int nid, gfp_t flags) 513{ 514 return NODE_DATA(nid)->node_zonelists + gfp_zonelist(flags); 515} 516 517#ifndef HAVE_ARCH_FREE_PAGE 518static inline void arch_free_page(struct page *page, int order) { } 519#endif 520#ifndef HAVE_ARCH_ALLOC_PAGE 521static inline void arch_alloc_page(struct page *page, int order) { } 522#endif 523#ifndef HAVE_ARCH_MAKE_PAGE_ACCESSIBLE 524static inline int arch_make_page_accessible(struct page *page) 525{ 526 return 0; 527} 528#endif 529 530struct page *__alloc_pages(gfp_t gfp, unsigned int order, int preferred_nid, 531 nodemask_t *nodemask); 532 533unsigned long __alloc_pages_bulk(gfp_t gfp, int preferred_nid, 534 nodemask_t *nodemask, int nr_pages, 535 struct list_head *page_list, 536 struct page **page_array); 537 538/* Bulk allocate order-0 pages */ 539static inline unsigned long 540alloc_pages_bulk_list(gfp_t gfp, unsigned long nr_pages, struct list_head *list) 541{ 542 return __alloc_pages_bulk(gfp, numa_mem_id(), NULL, nr_pages, list, NULL); 543} 544 545static inline unsigned long 546alloc_pages_bulk_array(gfp_t gfp, unsigned long nr_pages, struct page **page_array) 547{ 548 return __alloc_pages_bulk(gfp, numa_mem_id(), NULL, nr_pages, NULL, page_array); 549} 550 551static inline unsigned long 552alloc_pages_bulk_array_node(gfp_t gfp, int nid, unsigned long nr_pages, struct page **page_array) 553{ 554 if (nid == NUMA_NO_NODE) 555 nid = numa_mem_id(); 556 557 return __alloc_pages_bulk(gfp, nid, NULL, nr_pages, NULL, page_array); 558} 559 560/* 561 * Allocate pages, preferring the node given as nid. The node must be valid and 562 * online. For more general interface, see alloc_pages_node(). 563 */ 564static inline struct page * 565__alloc_pages_node(int nid, gfp_t gfp_mask, unsigned int order) 566{ 567 VM_BUG_ON(nid < 0 || nid >= MAX_NUMNODES); 568 VM_WARN_ON((gfp_mask & __GFP_THISNODE) && !node_online(nid)); 569 570 return __alloc_pages(gfp_mask, order, nid, NULL); 571} 572 573/* 574 * Allocate pages, preferring the node given as nid. When nid == NUMA_NO_NODE, 575 * prefer the current CPU's closest node. Otherwise node must be valid and 576 * online. 577 */ 578static inline struct page *alloc_pages_node(int nid, gfp_t gfp_mask, 579 unsigned int order) 580{ 581 if (nid == NUMA_NO_NODE) 582 nid = numa_mem_id(); 583 584 return __alloc_pages_node(nid, gfp_mask, order); 585} 586 587#ifdef CONFIG_NUMA 588struct page *alloc_pages(gfp_t gfp, unsigned int order); 589extern struct page *alloc_pages_vma(gfp_t gfp_mask, int order, 590 struct vm_area_struct *vma, unsigned long addr, 591 int node, bool hugepage); 592#define alloc_hugepage_vma(gfp_mask, vma, addr, order) \ 593 alloc_pages_vma(gfp_mask, order, vma, addr, numa_node_id(), true) 594#else 595static inline struct page *alloc_pages(gfp_t gfp_mask, unsigned int order) 596{ 597 return alloc_pages_node(numa_node_id(), gfp_mask, order); 598} 599#define alloc_pages_vma(gfp_mask, order, vma, addr, node, false)\ 600 alloc_pages(gfp_mask, order) 601#define alloc_hugepage_vma(gfp_mask, vma, addr, order) \ 602 alloc_pages(gfp_mask, order) 603#endif 604#define alloc_page(gfp_mask) alloc_pages(gfp_mask, 0) 605#define alloc_page_vma(gfp_mask, vma, addr) \ 606 alloc_pages_vma(gfp_mask, 0, vma, addr, numa_node_id(), false) 607 608extern unsigned long __get_free_pages(gfp_t gfp_mask, unsigned int order); 609extern unsigned long get_zeroed_page(gfp_t gfp_mask); 610 611void *alloc_pages_exact(size_t size, gfp_t gfp_mask); 612void free_pages_exact(void *virt, size_t size); 613void * __meminit alloc_pages_exact_nid(int nid, size_t size, gfp_t gfp_mask); 614 615#define __get_free_page(gfp_mask) \ 616 __get_free_pages((gfp_mask), 0) 617 618#define __get_dma_pages(gfp_mask, order) \ 619 __get_free_pages((gfp_mask) | GFP_DMA, (order)) 620 621extern void __free_pages(struct page *page, unsigned int order); 622extern void free_pages(unsigned long addr, unsigned int order); 623 624struct page_frag_cache; 625extern void __page_frag_cache_drain(struct page *page, unsigned int count); 626extern void *page_frag_alloc_align(struct page_frag_cache *nc, 627 unsigned int fragsz, gfp_t gfp_mask, 628 unsigned int align_mask); 629 630static inline void *page_frag_alloc(struct page_frag_cache *nc, 631 unsigned int fragsz, gfp_t gfp_mask) 632{ 633 return page_frag_alloc_align(nc, fragsz, gfp_mask, ~0u); 634} 635 636extern void page_frag_free(void *addr); 637 638#define __free_page(page) __free_pages((page), 0) 639#define free_page(addr) free_pages((addr), 0) 640 641void page_alloc_init(void); 642void drain_zone_pages(struct zone *zone, struct per_cpu_pages *pcp); 643void drain_all_pages(struct zone *zone); 644void drain_local_pages(struct zone *zone); 645 646void page_alloc_init_late(void); 647 648/* 649 * gfp_allowed_mask is set to GFP_BOOT_MASK during early boot to restrict what 650 * GFP flags are used before interrupts are enabled. Once interrupts are 651 * enabled, it is set to __GFP_BITS_MASK while the system is running. During 652 * hibernation, it is used by PM to avoid I/O during memory allocation while 653 * devices are suspended. 654 */ 655extern gfp_t gfp_allowed_mask; 656 657/* Returns true if the gfp_mask allows use of ALLOC_NO_WATERMARK */ 658bool gfp_pfmemalloc_allowed(gfp_t gfp_mask); 659 660extern void pm_restrict_gfp_mask(void); 661extern void pm_restore_gfp_mask(void); 662 663extern gfp_t vma_thp_gfp_mask(struct vm_area_struct *vma); 664 665#ifdef CONFIG_PM_SLEEP 666extern bool pm_suspended_storage(void); 667#else 668static inline bool pm_suspended_storage(void) 669{ 670 return false; 671} 672#endif /* CONFIG_PM_SLEEP */ 673 674#ifdef CONFIG_CONTIG_ALLOC 675/* The below functions must be run on a range from a single zone. */ 676extern int alloc_contig_range(unsigned long start, unsigned long end, 677 unsigned migratetype, gfp_t gfp_mask); 678extern struct page *alloc_contig_pages(unsigned long nr_pages, gfp_t gfp_mask, 679 int nid, nodemask_t *nodemask); 680#endif 681void free_contig_range(unsigned long pfn, unsigned long nr_pages); 682 683#ifdef CONFIG_CMA 684/* CMA stuff */ 685extern void init_cma_reserved_pageblock(struct page *page); 686#endif 687 688#endif /* __LINUX_GFP_H */ 689