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 */ 22 typedef unsigned int __bitwise gfp_t; 23 #endif 24 25 struct 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 #ifdef CONFIG_KASAN_HW_TAGS 58 #define ___GFP_SKIP_ZERO 0x1000000u 59 #define ___GFP_SKIP_KASAN_UNPOISON 0x2000000u 60 #define ___GFP_SKIP_KASAN_POISON 0x4000000u 61 #else 62 #define ___GFP_SKIP_ZERO 0 63 #define ___GFP_SKIP_KASAN_UNPOISON 0 64 #define ___GFP_SKIP_KASAN_POISON 0 65 #endif 66 #ifdef CONFIG_LOCKDEP 67 #define ___GFP_NOLOCKDEP 0x8000000u 68 #else 69 #define ___GFP_NOLOCKDEP 0 70 #endif 71 /* If the above are modified, __GFP_BITS_SHIFT may need updating */ 72 73 /* 74 * Physical address zone modifiers (see linux/mmzone.h - low four bits) 75 * 76 * Do not put any conditional on these. If necessary modify the definitions 77 * without the underscores and use them consistently. The definitions here may 78 * be used in bit comparisons. 79 */ 80 #define __GFP_DMA ((__force gfp_t)___GFP_DMA) 81 #define __GFP_HIGHMEM ((__force gfp_t)___GFP_HIGHMEM) 82 #define __GFP_DMA32 ((__force gfp_t)___GFP_DMA32) 83 #define __GFP_MOVABLE ((__force gfp_t)___GFP_MOVABLE) /* ZONE_MOVABLE allowed */ 84 #define GFP_ZONEMASK (__GFP_DMA|__GFP_HIGHMEM|__GFP_DMA32|__GFP_MOVABLE) 85 86 /** 87 * DOC: Page mobility and placement hints 88 * 89 * Page mobility and placement hints 90 * --------------------------------- 91 * 92 * These flags provide hints about how mobile the page is. Pages with similar 93 * mobility are placed within the same pageblocks to minimise problems due 94 * to external fragmentation. 95 * 96 * %__GFP_MOVABLE (also a zone modifier) indicates that the page can be 97 * moved by page migration during memory compaction or can be reclaimed. 98 * 99 * %__GFP_RECLAIMABLE is used for slab allocations that specify 100 * SLAB_RECLAIM_ACCOUNT and whose pages can be freed via shrinkers. 101 * 102 * %__GFP_WRITE indicates the caller intends to dirty the page. Where possible, 103 * these pages will be spread between local zones to avoid all the dirty 104 * pages being in one zone (fair zone allocation policy). 105 * 106 * %__GFP_HARDWALL enforces the cpuset memory allocation policy. 107 * 108 * %__GFP_THISNODE forces the allocation to be satisfied from the requested 109 * node with no fallbacks or placement policy enforcements. 110 * 111 * %__GFP_ACCOUNT causes the allocation to be accounted to kmemcg. 112 */ 113 #define __GFP_RECLAIMABLE ((__force gfp_t)___GFP_RECLAIMABLE) 114 #define __GFP_WRITE ((__force gfp_t)___GFP_WRITE) 115 #define __GFP_HARDWALL ((__force gfp_t)___GFP_HARDWALL) 116 #define __GFP_THISNODE ((__force gfp_t)___GFP_THISNODE) 117 #define __GFP_ACCOUNT ((__force gfp_t)___GFP_ACCOUNT) 118 119 /** 120 * DOC: Watermark modifiers 121 * 122 * Watermark modifiers -- controls access to emergency reserves 123 * ------------------------------------------------------------ 124 * 125 * %__GFP_HIGH indicates that the caller is high-priority and that granting 126 * the request is necessary before the system can make forward progress. 127 * For example, creating an IO context to clean pages. 128 * 129 * %__GFP_ATOMIC indicates that the caller cannot reclaim or sleep and is 130 * high priority. Users are typically interrupt handlers. This may be 131 * used in conjunction with %__GFP_HIGH 132 * 133 * %__GFP_MEMALLOC allows access to all memory. This should only be used when 134 * the caller guarantees the allocation will allow more memory to be freed 135 * very shortly e.g. process exiting or swapping. Users either should 136 * be the MM or co-ordinating closely with the VM (e.g. swap over NFS). 137 * Users of this flag have to be extremely careful to not deplete the reserve 138 * completely and implement a throttling mechanism which controls the 139 * consumption of the reserve based on the amount of freed memory. 140 * Usage of a pre-allocated pool (e.g. mempool) should be always considered 141 * before using this flag. 142 * 143 * %__GFP_NOMEMALLOC is used to explicitly forbid access to emergency reserves. 144 * This takes precedence over the %__GFP_MEMALLOC flag if both are set. 145 */ 146 #define __GFP_ATOMIC ((__force gfp_t)___GFP_ATOMIC) 147 #define __GFP_HIGH ((__force gfp_t)___GFP_HIGH) 148 #define __GFP_MEMALLOC ((__force gfp_t)___GFP_MEMALLOC) 149 #define __GFP_NOMEMALLOC ((__force gfp_t)___GFP_NOMEMALLOC) 150 151 /** 152 * DOC: Reclaim modifiers 153 * 154 * Reclaim modifiers 155 * ----------------- 156 * Please note that all the following flags are only applicable to sleepable 157 * allocations (e.g. %GFP_NOWAIT and %GFP_ATOMIC will ignore them). 158 * 159 * %__GFP_IO can start physical IO. 160 * 161 * %__GFP_FS can call down to the low-level FS. Clearing the flag avoids the 162 * allocator recursing into the filesystem which might already be holding 163 * locks. 164 * 165 * %__GFP_DIRECT_RECLAIM indicates that the caller may enter direct reclaim. 166 * This flag can be cleared to avoid unnecessary delays when a fallback 167 * option is available. 168 * 169 * %__GFP_KSWAPD_RECLAIM indicates that the caller wants to wake kswapd when 170 * the low watermark is reached and have it reclaim pages until the high 171 * watermark is reached. A caller may wish to clear this flag when fallback 172 * options are available and the reclaim is likely to disrupt the system. The 173 * canonical example is THP allocation where a fallback is cheap but 174 * reclaim/compaction may cause indirect stalls. 175 * 176 * %__GFP_RECLAIM is shorthand to allow/forbid both direct and kswapd reclaim. 177 * 178 * The default allocator behavior depends on the request size. We have a concept 179 * of so called costly allocations (with order > %PAGE_ALLOC_COSTLY_ORDER). 180 * !costly allocations are too essential to fail so they are implicitly 181 * non-failing by default (with some exceptions like OOM victims might fail so 182 * the caller still has to check for failures) while costly requests try to be 183 * not disruptive and back off even without invoking the OOM killer. 184 * The following three modifiers might be used to override some of these 185 * implicit rules 186 * 187 * %__GFP_NORETRY: The VM implementation will try only very lightweight 188 * memory direct reclaim to get some memory under memory pressure (thus 189 * it can sleep). It will avoid disruptive actions like OOM killer. The 190 * caller must handle the failure which is quite likely to happen under 191 * heavy memory pressure. The flag is suitable when failure can easily be 192 * handled at small cost, such as reduced throughput 193 * 194 * %__GFP_RETRY_MAYFAIL: The VM implementation will retry memory reclaim 195 * procedures that have previously failed if there is some indication 196 * that progress has been made else where. It can wait for other 197 * tasks to attempt high level approaches to freeing memory such as 198 * compaction (which removes fragmentation) and page-out. 199 * There is still a definite limit to the number of retries, but it is 200 * a larger limit than with %__GFP_NORETRY. 201 * Allocations with this flag may fail, but only when there is 202 * genuinely little unused memory. While these allocations do not 203 * directly trigger the OOM killer, their failure indicates that 204 * the system is likely to need to use the OOM killer soon. The 205 * caller must handle failure, but can reasonably do so by failing 206 * a higher-level request, or completing it only in a much less 207 * efficient manner. 208 * If the allocation does fail, and the caller is in a position to 209 * free some non-essential memory, doing so could benefit the system 210 * as a whole. 211 * 212 * %__GFP_NOFAIL: The VM implementation _must_ retry infinitely: the caller 213 * cannot handle allocation failures. The allocation could block 214 * indefinitely but will never return with failure. Testing for 215 * failure is pointless. 216 * New users should be evaluated carefully (and the flag should be 217 * used only when there is no reasonable failure policy) but it is 218 * definitely preferable to use the flag rather than opencode endless 219 * loop around allocator. 220 * Using this flag for costly allocations is _highly_ discouraged. 221 */ 222 #define __GFP_IO ((__force gfp_t)___GFP_IO) 223 #define __GFP_FS ((__force gfp_t)___GFP_FS) 224 #define __GFP_DIRECT_RECLAIM ((__force gfp_t)___GFP_DIRECT_RECLAIM) /* Caller can reclaim */ 225 #define __GFP_KSWAPD_RECLAIM ((__force gfp_t)___GFP_KSWAPD_RECLAIM) /* kswapd can wake */ 226 #define __GFP_RECLAIM ((__force gfp_t)(___GFP_DIRECT_RECLAIM|___GFP_KSWAPD_RECLAIM)) 227 #define __GFP_RETRY_MAYFAIL ((__force gfp_t)___GFP_RETRY_MAYFAIL) 228 #define __GFP_NOFAIL ((__force gfp_t)___GFP_NOFAIL) 229 #define __GFP_NORETRY ((__force gfp_t)___GFP_NORETRY) 230 231 /** 232 * DOC: Action modifiers 233 * 234 * Action modifiers 235 * ---------------- 236 * 237 * %__GFP_NOWARN suppresses allocation failure reports. 238 * 239 * %__GFP_COMP address compound page metadata. 240 * 241 * %__GFP_ZERO returns a zeroed page on success. 242 * 243 * %__GFP_ZEROTAGS zeroes memory tags at allocation time if the memory itself 244 * is being zeroed (either via __GFP_ZERO or via init_on_alloc, provided that 245 * __GFP_SKIP_ZERO is not set). This flag is intended for optimization: setting 246 * memory tags at the same time as zeroing memory has minimal additional 247 * performace impact. 248 * 249 * %__GFP_SKIP_KASAN_UNPOISON makes KASAN skip unpoisoning on page allocation. 250 * Only effective in HW_TAGS mode. 251 * 252 * %__GFP_SKIP_KASAN_POISON makes KASAN skip poisoning on page deallocation. 253 * Typically, used for userspace pages. Only effective in HW_TAGS mode. 254 */ 255 #define __GFP_NOWARN ((__force gfp_t)___GFP_NOWARN) 256 #define __GFP_COMP ((__force gfp_t)___GFP_COMP) 257 #define __GFP_ZERO ((__force gfp_t)___GFP_ZERO) 258 #define __GFP_ZEROTAGS ((__force gfp_t)___GFP_ZEROTAGS) 259 #define __GFP_SKIP_ZERO ((__force gfp_t)___GFP_SKIP_ZERO) 260 #define __GFP_SKIP_KASAN_UNPOISON ((__force gfp_t)___GFP_SKIP_KASAN_UNPOISON) 261 #define __GFP_SKIP_KASAN_POISON ((__force gfp_t)___GFP_SKIP_KASAN_POISON) 262 263 /* Disable lockdep for GFP context tracking */ 264 #define __GFP_NOLOCKDEP ((__force gfp_t)___GFP_NOLOCKDEP) 265 266 /* Room for N __GFP_FOO bits */ 267 #define __GFP_BITS_SHIFT (27 + IS_ENABLED(CONFIG_LOCKDEP)) 268 #define __GFP_BITS_MASK ((__force gfp_t)((1 << __GFP_BITS_SHIFT) - 1)) 269 270 /** 271 * DOC: Useful GFP flag combinations 272 * 273 * Useful GFP flag combinations 274 * ---------------------------- 275 * 276 * Useful GFP flag combinations that are commonly used. It is recommended 277 * that subsystems start with one of these combinations and then set/clear 278 * %__GFP_FOO flags as necessary. 279 * 280 * %GFP_ATOMIC users can not sleep and need the allocation to succeed. A lower 281 * watermark is applied to allow access to "atomic reserves". 282 * The current implementation doesn't support NMI and few other strict 283 * non-preemptive contexts (e.g. raw_spin_lock). The same applies to %GFP_NOWAIT. 284 * 285 * %GFP_KERNEL is typical for kernel-internal allocations. The caller requires 286 * %ZONE_NORMAL or a lower zone for direct access but can direct reclaim. 287 * 288 * %GFP_KERNEL_ACCOUNT is the same as GFP_KERNEL, except the allocation is 289 * accounted to kmemcg. 290 * 291 * %GFP_NOWAIT is for kernel allocations that should not stall for direct 292 * reclaim, start physical IO or use any filesystem callback. 293 * 294 * %GFP_NOIO will use direct reclaim to discard clean pages or slab pages 295 * that do not require the starting of any physical IO. 296 * Please try to avoid using this flag directly and instead use 297 * memalloc_noio_{save,restore} to mark the whole scope which cannot 298 * perform any IO with a short explanation why. All allocation requests 299 * will inherit GFP_NOIO implicitly. 300 * 301 * %GFP_NOFS will use direct reclaim but will not use any filesystem interfaces. 302 * Please try to avoid using this flag directly and instead use 303 * memalloc_nofs_{save,restore} to mark the whole scope which cannot/shouldn't 304 * recurse into the FS layer with a short explanation why. All allocation 305 * requests will inherit GFP_NOFS implicitly. 306 * 307 * %GFP_USER is for userspace allocations that also need to be directly 308 * accessibly by the kernel or hardware. It is typically used by hardware 309 * for buffers that are mapped to userspace (e.g. graphics) that hardware 310 * still must DMA to. cpuset limits are enforced for these allocations. 311 * 312 * %GFP_DMA exists for historical reasons and should be avoided where possible. 313 * The flags indicates that the caller requires that the lowest zone be 314 * used (%ZONE_DMA or 16M on x86-64). Ideally, this would be removed but 315 * it would require careful auditing as some users really require it and 316 * others use the flag to avoid lowmem reserves in %ZONE_DMA and treat the 317 * lowest zone as a type of emergency reserve. 318 * 319 * %GFP_DMA32 is similar to %GFP_DMA except that the caller requires a 32-bit 320 * address. Note that kmalloc(..., GFP_DMA32) does not return DMA32 memory 321 * because the DMA32 kmalloc cache array is not implemented. 322 * (Reason: there is no such user in kernel). 323 * 324 * %GFP_HIGHUSER is for userspace allocations that may be mapped to userspace, 325 * do not need to be directly accessible by the kernel but that cannot 326 * move once in use. An example may be a hardware allocation that maps 327 * data directly into userspace but has no addressing limitations. 328 * 329 * %GFP_HIGHUSER_MOVABLE is for userspace allocations that the kernel does not 330 * need direct access to but can use kmap() when access is required. They 331 * are expected to be movable via page reclaim or page migration. Typically, 332 * pages on the LRU would also be allocated with %GFP_HIGHUSER_MOVABLE. 333 * 334 * %GFP_TRANSHUGE and %GFP_TRANSHUGE_LIGHT are used for THP allocations. They 335 * are compound allocations that will generally fail quickly if memory is not 336 * available and will not wake kswapd/kcompactd on failure. The _LIGHT 337 * version does not attempt reclaim/compaction at all and is by default used 338 * in page fault path, while the non-light is used by khugepaged. 339 */ 340 #define GFP_ATOMIC (__GFP_HIGH|__GFP_ATOMIC|__GFP_KSWAPD_RECLAIM) 341 #define GFP_KERNEL (__GFP_RECLAIM | __GFP_IO | __GFP_FS) 342 #define GFP_KERNEL_ACCOUNT (GFP_KERNEL | __GFP_ACCOUNT) 343 #define GFP_NOWAIT (__GFP_KSWAPD_RECLAIM) 344 #define GFP_NOIO (__GFP_RECLAIM) 345 #define GFP_NOFS (__GFP_RECLAIM | __GFP_IO) 346 #define GFP_USER (__GFP_RECLAIM | __GFP_IO | __GFP_FS | __GFP_HARDWALL) 347 #define GFP_DMA __GFP_DMA 348 #define GFP_DMA32 __GFP_DMA32 349 #define GFP_HIGHUSER (GFP_USER | __GFP_HIGHMEM) 350 #define GFP_HIGHUSER_MOVABLE (GFP_HIGHUSER | __GFP_MOVABLE | \ 351 __GFP_SKIP_KASAN_POISON) 352 #define GFP_TRANSHUGE_LIGHT ((GFP_HIGHUSER_MOVABLE | __GFP_COMP | \ 353 __GFP_NOMEMALLOC | __GFP_NOWARN) & ~__GFP_RECLAIM) 354 #define GFP_TRANSHUGE (GFP_TRANSHUGE_LIGHT | __GFP_DIRECT_RECLAIM) 355 356 /* Convert GFP flags to their corresponding migrate type */ 357 #define GFP_MOVABLE_MASK (__GFP_RECLAIMABLE|__GFP_MOVABLE) 358 #define GFP_MOVABLE_SHIFT 3 359 360 static inline int gfp_migratetype(const gfp_t gfp_flags) 361 { 362 VM_WARN_ON((gfp_flags & GFP_MOVABLE_MASK) == GFP_MOVABLE_MASK); 363 BUILD_BUG_ON((1UL << GFP_MOVABLE_SHIFT) != ___GFP_MOVABLE); 364 BUILD_BUG_ON((___GFP_MOVABLE >> GFP_MOVABLE_SHIFT) != MIGRATE_MOVABLE); 365 366 if (unlikely(page_group_by_mobility_disabled)) 367 return MIGRATE_UNMOVABLE; 368 369 /* Group based on mobility */ 370 return (gfp_flags & GFP_MOVABLE_MASK) >> GFP_MOVABLE_SHIFT; 371 } 372 #undef GFP_MOVABLE_MASK 373 #undef GFP_MOVABLE_SHIFT 374 375 static inline bool gfpflags_allow_blocking(const gfp_t gfp_flags) 376 { 377 return !!(gfp_flags & __GFP_DIRECT_RECLAIM); 378 } 379 380 /** 381 * gfpflags_normal_context - is gfp_flags a normal sleepable context? 382 * @gfp_flags: gfp_flags to test 383 * 384 * Test whether @gfp_flags indicates that the allocation is from the 385 * %current context and allowed to sleep. 386 * 387 * An allocation being allowed to block doesn't mean it owns the %current 388 * context. When direct reclaim path tries to allocate memory, the 389 * allocation context is nested inside whatever %current was doing at the 390 * time of the original allocation. The nested allocation may be allowed 391 * to block but modifying anything %current owns can corrupt the outer 392 * context's expectations. 393 * 394 * %true result from this function indicates that the allocation context 395 * can sleep and use anything that's associated with %current. 396 */ 397 static inline bool gfpflags_normal_context(const gfp_t gfp_flags) 398 { 399 return (gfp_flags & (__GFP_DIRECT_RECLAIM | __GFP_MEMALLOC)) == 400 __GFP_DIRECT_RECLAIM; 401 } 402 403 #ifdef CONFIG_HIGHMEM 404 #define OPT_ZONE_HIGHMEM ZONE_HIGHMEM 405 #else 406 #define OPT_ZONE_HIGHMEM ZONE_NORMAL 407 #endif 408 409 #ifdef CONFIG_ZONE_DMA 410 #define OPT_ZONE_DMA ZONE_DMA 411 #else 412 #define OPT_ZONE_DMA ZONE_NORMAL 413 #endif 414 415 #ifdef CONFIG_ZONE_DMA32 416 #define OPT_ZONE_DMA32 ZONE_DMA32 417 #else 418 #define OPT_ZONE_DMA32 ZONE_NORMAL 419 #endif 420 421 /* 422 * GFP_ZONE_TABLE is a word size bitstring that is used for looking up the 423 * zone to use given the lowest 4 bits of gfp_t. Entries are GFP_ZONES_SHIFT 424 * bits long and there are 16 of them to cover all possible combinations of 425 * __GFP_DMA, __GFP_DMA32, __GFP_MOVABLE and __GFP_HIGHMEM. 426 * 427 * The zone fallback order is MOVABLE=>HIGHMEM=>NORMAL=>DMA32=>DMA. 428 * But GFP_MOVABLE is not only a zone specifier but also an allocation 429 * policy. Therefore __GFP_MOVABLE plus another zone selector is valid. 430 * Only 1 bit of the lowest 3 bits (DMA,DMA32,HIGHMEM) can be set to "1". 431 * 432 * bit result 433 * ================= 434 * 0x0 => NORMAL 435 * 0x1 => DMA or NORMAL 436 * 0x2 => HIGHMEM or NORMAL 437 * 0x3 => BAD (DMA+HIGHMEM) 438 * 0x4 => DMA32 or NORMAL 439 * 0x5 => BAD (DMA+DMA32) 440 * 0x6 => BAD (HIGHMEM+DMA32) 441 * 0x7 => BAD (HIGHMEM+DMA32+DMA) 442 * 0x8 => NORMAL (MOVABLE+0) 443 * 0x9 => DMA or NORMAL (MOVABLE+DMA) 444 * 0xa => MOVABLE (Movable is valid only if HIGHMEM is set too) 445 * 0xb => BAD (MOVABLE+HIGHMEM+DMA) 446 * 0xc => DMA32 or NORMAL (MOVABLE+DMA32) 447 * 0xd => BAD (MOVABLE+DMA32+DMA) 448 * 0xe => BAD (MOVABLE+DMA32+HIGHMEM) 449 * 0xf => BAD (MOVABLE+DMA32+HIGHMEM+DMA) 450 * 451 * GFP_ZONES_SHIFT must be <= 2 on 32 bit platforms. 452 */ 453 454 #if defined(CONFIG_ZONE_DEVICE) && (MAX_NR_ZONES-1) <= 4 455 /* ZONE_DEVICE is not a valid GFP zone specifier */ 456 #define GFP_ZONES_SHIFT 2 457 #else 458 #define GFP_ZONES_SHIFT ZONES_SHIFT 459 #endif 460 461 #if 16 * GFP_ZONES_SHIFT > BITS_PER_LONG 462 #error GFP_ZONES_SHIFT too large to create GFP_ZONE_TABLE integer 463 #endif 464 465 #define GFP_ZONE_TABLE ( \ 466 (ZONE_NORMAL << 0 * GFP_ZONES_SHIFT) \ 467 | (OPT_ZONE_DMA << ___GFP_DMA * GFP_ZONES_SHIFT) \ 468 | (OPT_ZONE_HIGHMEM << ___GFP_HIGHMEM * GFP_ZONES_SHIFT) \ 469 | (OPT_ZONE_DMA32 << ___GFP_DMA32 * GFP_ZONES_SHIFT) \ 470 | (ZONE_NORMAL << ___GFP_MOVABLE * GFP_ZONES_SHIFT) \ 471 | (OPT_ZONE_DMA << (___GFP_MOVABLE | ___GFP_DMA) * GFP_ZONES_SHIFT) \ 472 | (ZONE_MOVABLE << (___GFP_MOVABLE | ___GFP_HIGHMEM) * GFP_ZONES_SHIFT)\ 473 | (OPT_ZONE_DMA32 << (___GFP_MOVABLE | ___GFP_DMA32) * GFP_ZONES_SHIFT)\ 474 ) 475 476 /* 477 * GFP_ZONE_BAD is a bitmap for all combinations of __GFP_DMA, __GFP_DMA32 478 * __GFP_HIGHMEM and __GFP_MOVABLE that are not permitted. One flag per 479 * entry starting with bit 0. Bit is set if the combination is not 480 * allowed. 481 */ 482 #define GFP_ZONE_BAD ( \ 483 1 << (___GFP_DMA | ___GFP_HIGHMEM) \ 484 | 1 << (___GFP_DMA | ___GFP_DMA32) \ 485 | 1 << (___GFP_DMA32 | ___GFP_HIGHMEM) \ 486 | 1 << (___GFP_DMA | ___GFP_DMA32 | ___GFP_HIGHMEM) \ 487 | 1 << (___GFP_MOVABLE | ___GFP_HIGHMEM | ___GFP_DMA) \ 488 | 1 << (___GFP_MOVABLE | ___GFP_DMA32 | ___GFP_DMA) \ 489 | 1 << (___GFP_MOVABLE | ___GFP_DMA32 | ___GFP_HIGHMEM) \ 490 | 1 << (___GFP_MOVABLE | ___GFP_DMA32 | ___GFP_DMA | ___GFP_HIGHMEM) \ 491 ) 492 493 static inline enum zone_type gfp_zone(gfp_t flags) 494 { 495 enum zone_type z; 496 int bit = (__force int) (flags & GFP_ZONEMASK); 497 498 z = (GFP_ZONE_TABLE >> (bit * GFP_ZONES_SHIFT)) & 499 ((1 << GFP_ZONES_SHIFT) - 1); 500 VM_BUG_ON((GFP_ZONE_BAD >> bit) & 1); 501 return z; 502 } 503 504 /* 505 * There is only one page-allocator function, and two main namespaces to 506 * it. The alloc_page*() variants return 'struct page *' and as such 507 * can allocate highmem pages, the *get*page*() variants return 508 * virtual kernel addresses to the allocated page(s). 509 */ 510 511 static inline int gfp_zonelist(gfp_t flags) 512 { 513 #ifdef CONFIG_NUMA 514 if (unlikely(flags & __GFP_THISNODE)) 515 return ZONELIST_NOFALLBACK; 516 #endif 517 return ZONELIST_FALLBACK; 518 } 519 520 /* 521 * We get the zone list from the current node and the gfp_mask. 522 * This zone list contains a maximum of MAX_NUMNODES*MAX_NR_ZONES zones. 523 * There are two zonelists per node, one for all zones with memory and 524 * one containing just zones from the node the zonelist belongs to. 525 * 526 * For the case of non-NUMA systems the NODE_DATA() gets optimized to 527 * &contig_page_data at compile-time. 528 */ 529 static inline struct zonelist *node_zonelist(int nid, gfp_t flags) 530 { 531 return NODE_DATA(nid)->node_zonelists + gfp_zonelist(flags); 532 } 533 534 #ifndef HAVE_ARCH_FREE_PAGE 535 static inline void arch_free_page(struct page *page, int order) { } 536 #endif 537 #ifndef HAVE_ARCH_ALLOC_PAGE 538 static inline void arch_alloc_page(struct page *page, int order) { } 539 #endif 540 541 struct page *__alloc_pages(gfp_t gfp, unsigned int order, int preferred_nid, 542 nodemask_t *nodemask); 543 struct folio *__folio_alloc(gfp_t gfp, unsigned int order, int preferred_nid, 544 nodemask_t *nodemask); 545 546 unsigned long __alloc_pages_bulk(gfp_t gfp, int preferred_nid, 547 nodemask_t *nodemask, int nr_pages, 548 struct list_head *page_list, 549 struct page **page_array); 550 551 unsigned long alloc_pages_bulk_array_mempolicy(gfp_t gfp, 552 unsigned long nr_pages, 553 struct page **page_array); 554 555 /* Bulk allocate order-0 pages */ 556 static inline unsigned long 557 alloc_pages_bulk_list(gfp_t gfp, unsigned long nr_pages, struct list_head *list) 558 { 559 return __alloc_pages_bulk(gfp, numa_mem_id(), NULL, nr_pages, list, NULL); 560 } 561 562 static inline unsigned long 563 alloc_pages_bulk_array(gfp_t gfp, unsigned long nr_pages, struct page **page_array) 564 { 565 return __alloc_pages_bulk(gfp, numa_mem_id(), NULL, nr_pages, NULL, page_array); 566 } 567 568 static inline unsigned long 569 alloc_pages_bulk_array_node(gfp_t gfp, int nid, unsigned long nr_pages, struct page **page_array) 570 { 571 if (nid == NUMA_NO_NODE) 572 nid = numa_mem_id(); 573 574 return __alloc_pages_bulk(gfp, nid, NULL, nr_pages, NULL, page_array); 575 } 576 577 /* 578 * Allocate pages, preferring the node given as nid. The node must be valid and 579 * online. For more general interface, see alloc_pages_node(). 580 */ 581 static inline struct page * 582 __alloc_pages_node(int nid, gfp_t gfp_mask, unsigned int order) 583 { 584 VM_BUG_ON(nid < 0 || nid >= MAX_NUMNODES); 585 VM_WARN_ON((gfp_mask & __GFP_THISNODE) && !node_online(nid)); 586 587 return __alloc_pages(gfp_mask, order, nid, NULL); 588 } 589 590 static inline 591 struct folio *__folio_alloc_node(gfp_t gfp, unsigned int order, int nid) 592 { 593 VM_BUG_ON(nid < 0 || nid >= MAX_NUMNODES); 594 VM_WARN_ON((gfp & __GFP_THISNODE) && !node_online(nid)); 595 596 return __folio_alloc(gfp, order, nid, NULL); 597 } 598 599 /* 600 * Allocate pages, preferring the node given as nid. When nid == NUMA_NO_NODE, 601 * prefer the current CPU's closest node. Otherwise node must be valid and 602 * online. 603 */ 604 static inline struct page *alloc_pages_node(int nid, gfp_t gfp_mask, 605 unsigned int order) 606 { 607 if (nid == NUMA_NO_NODE) 608 nid = numa_mem_id(); 609 610 return __alloc_pages_node(nid, gfp_mask, order); 611 } 612 613 #ifdef CONFIG_NUMA 614 struct page *alloc_pages(gfp_t gfp, unsigned int order); 615 struct folio *folio_alloc(gfp_t gfp, unsigned order); 616 struct page *alloc_pages_vma(gfp_t gfp_mask, int order, 617 struct vm_area_struct *vma, unsigned long addr, 618 bool hugepage); 619 struct folio *vma_alloc_folio(gfp_t gfp, int order, struct vm_area_struct *vma, 620 unsigned long addr, bool hugepage); 621 #define alloc_hugepage_vma(gfp_mask, vma, addr, order) \ 622 alloc_pages_vma(gfp_mask, order, vma, addr, true) 623 #else 624 static inline struct page *alloc_pages(gfp_t gfp_mask, unsigned int order) 625 { 626 return alloc_pages_node(numa_node_id(), gfp_mask, order); 627 } 628 static inline struct folio *folio_alloc(gfp_t gfp, unsigned int order) 629 { 630 return __folio_alloc_node(gfp, order, numa_node_id()); 631 } 632 #define alloc_pages_vma(gfp_mask, order, vma, addr, hugepage) \ 633 alloc_pages(gfp_mask, order) 634 #define vma_alloc_folio(gfp, order, vma, addr, hugepage) \ 635 folio_alloc(gfp, order) 636 #define alloc_hugepage_vma(gfp_mask, vma, addr, order) \ 637 alloc_pages(gfp_mask, order) 638 #endif 639 #define alloc_page(gfp_mask) alloc_pages(gfp_mask, 0) 640 #define alloc_page_vma(gfp_mask, vma, addr) \ 641 alloc_pages_vma(gfp_mask, 0, vma, addr, false) 642 643 extern unsigned long __get_free_pages(gfp_t gfp_mask, unsigned int order); 644 extern unsigned long get_zeroed_page(gfp_t gfp_mask); 645 646 void *alloc_pages_exact(size_t size, gfp_t gfp_mask) __alloc_size(1); 647 void free_pages_exact(void *virt, size_t size); 648 __meminit void *alloc_pages_exact_nid(int nid, size_t size, gfp_t gfp_mask) __alloc_size(2); 649 650 #define __get_free_page(gfp_mask) \ 651 __get_free_pages((gfp_mask), 0) 652 653 #define __get_dma_pages(gfp_mask, order) \ 654 __get_free_pages((gfp_mask) | GFP_DMA, (order)) 655 656 extern void __free_pages(struct page *page, unsigned int order); 657 extern void free_pages(unsigned long addr, unsigned int order); 658 659 struct page_frag_cache; 660 extern void __page_frag_cache_drain(struct page *page, unsigned int count); 661 extern void *page_frag_alloc_align(struct page_frag_cache *nc, 662 unsigned int fragsz, gfp_t gfp_mask, 663 unsigned int align_mask); 664 665 static inline void *page_frag_alloc(struct page_frag_cache *nc, 666 unsigned int fragsz, gfp_t gfp_mask) 667 { 668 return page_frag_alloc_align(nc, fragsz, gfp_mask, ~0u); 669 } 670 671 extern void page_frag_free(void *addr); 672 673 #define __free_page(page) __free_pages((page), 0) 674 #define free_page(addr) free_pages((addr), 0) 675 676 void page_alloc_init(void); 677 void drain_zone_pages(struct zone *zone, struct per_cpu_pages *pcp); 678 void drain_all_pages(struct zone *zone); 679 void drain_local_pages(struct zone *zone); 680 681 void page_alloc_init_late(void); 682 683 /* 684 * gfp_allowed_mask is set to GFP_BOOT_MASK during early boot to restrict what 685 * GFP flags are used before interrupts are enabled. Once interrupts are 686 * enabled, it is set to __GFP_BITS_MASK while the system is running. During 687 * hibernation, it is used by PM to avoid I/O during memory allocation while 688 * devices are suspended. 689 */ 690 extern gfp_t gfp_allowed_mask; 691 692 /* Returns true if the gfp_mask allows use of ALLOC_NO_WATERMARK */ 693 bool gfp_pfmemalloc_allowed(gfp_t gfp_mask); 694 695 extern void pm_restrict_gfp_mask(void); 696 extern void pm_restore_gfp_mask(void); 697 698 extern gfp_t vma_thp_gfp_mask(struct vm_area_struct *vma); 699 700 #ifdef CONFIG_PM_SLEEP 701 extern bool pm_suspended_storage(void); 702 #else 703 static inline bool pm_suspended_storage(void) 704 { 705 return false; 706 } 707 #endif /* CONFIG_PM_SLEEP */ 708 709 #ifdef CONFIG_CONTIG_ALLOC 710 /* The below functions must be run on a range from a single zone. */ 711 extern int alloc_contig_range(unsigned long start, unsigned long end, 712 unsigned migratetype, gfp_t gfp_mask); 713 extern struct page *alloc_contig_pages(unsigned long nr_pages, gfp_t gfp_mask, 714 int nid, nodemask_t *nodemask); 715 #endif 716 void free_contig_range(unsigned long pfn, unsigned long nr_pages); 717 718 #ifdef CONFIG_CMA 719 /* CMA stuff */ 720 extern void init_cma_reserved_pageblock(struct page *page); 721 #endif 722 723 #endif /* __LINUX_GFP_H */ 724