| 1 | /* |
| 2 | * Copyright (c) Meta Platforms, Inc. and affiliates. |
| 3 | * All rights reserved. |
| 4 | * |
| 5 | * This source code is licensed under both the BSD-style license (found in the |
| 6 | * LICENSE file in the root directory of this source tree) and the GPLv2 (found |
| 7 | * in the COPYING file in the root directory of this source tree). |
| 8 | * You may select, at your option, one of the above-listed licenses. |
| 9 | */ |
| 10 | |
| 11 | #ifndef ZSTD_CWKSP_H |
| 12 | #define ZSTD_CWKSP_H |
| 13 | |
| 14 | /*-************************************* |
| 15 | * Dependencies |
| 16 | ***************************************/ |
| 17 | #include "../common/allocations.h" /* ZSTD_customMalloc, ZSTD_customFree */ |
| 18 | #include "../common/zstd_internal.h" |
| 19 | #include "../common/portability_macros.h" |
| 20 | |
| 21 | #if defined (__cplusplus) |
| 22 | extern "C" { |
| 23 | #endif |
| 24 | |
| 25 | /*-************************************* |
| 26 | * Constants |
| 27 | ***************************************/ |
| 28 | |
| 29 | /* Since the workspace is effectively its own little malloc implementation / |
| 30 | * arena, when we run under ASAN, we should similarly insert redzones between |
| 31 | * each internal element of the workspace, so ASAN will catch overruns that |
| 32 | * reach outside an object but that stay inside the workspace. |
| 33 | * |
| 34 | * This defines the size of that redzone. |
| 35 | */ |
| 36 | #ifndef ZSTD_CWKSP_ASAN_REDZONE_SIZE |
| 37 | #define ZSTD_CWKSP_ASAN_REDZONE_SIZE 128 |
| 38 | #endif |
| 39 | |
| 40 | |
| 41 | /* Set our tables and aligneds to align by 64 bytes */ |
| 42 | #define ZSTD_CWKSP_ALIGNMENT_BYTES 64 |
| 43 | |
| 44 | /*-************************************* |
| 45 | * Structures |
| 46 | ***************************************/ |
| 47 | typedef enum { |
| 48 | ZSTD_cwksp_alloc_objects, |
| 49 | ZSTD_cwksp_alloc_aligned_init_once, |
| 50 | ZSTD_cwksp_alloc_aligned, |
| 51 | ZSTD_cwksp_alloc_buffers |
| 52 | } ZSTD_cwksp_alloc_phase_e; |
| 53 | |
| 54 | /** |
| 55 | * Used to describe whether the workspace is statically allocated (and will not |
| 56 | * necessarily ever be freed), or if it's dynamically allocated and we can |
| 57 | * expect a well-formed caller to free this. |
| 58 | */ |
| 59 | typedef enum { |
| 60 | ZSTD_cwksp_dynamic_alloc, |
| 61 | ZSTD_cwksp_static_alloc |
| 62 | } ZSTD_cwksp_static_alloc_e; |
| 63 | |
| 64 | /** |
| 65 | * Zstd fits all its internal datastructures into a single continuous buffer, |
| 66 | * so that it only needs to perform a single OS allocation (or so that a buffer |
| 67 | * can be provided to it and it can perform no allocations at all). This buffer |
| 68 | * is called the workspace. |
| 69 | * |
| 70 | * Several optimizations complicate that process of allocating memory ranges |
| 71 | * from this workspace for each internal datastructure: |
| 72 | * |
| 73 | * - These different internal datastructures have different setup requirements: |
| 74 | * |
| 75 | * - The static objects need to be cleared once and can then be trivially |
| 76 | * reused for each compression. |
| 77 | * |
| 78 | * - Various buffers don't need to be initialized at all--they are always |
| 79 | * written into before they're read. |
| 80 | * |
| 81 | * - The matchstate tables have a unique requirement that they don't need |
| 82 | * their memory to be totally cleared, but they do need the memory to have |
| 83 | * some bound, i.e., a guarantee that all values in the memory they've been |
| 84 | * allocated is less than some maximum value (which is the starting value |
| 85 | * for the indices that they will then use for compression). When this |
| 86 | * guarantee is provided to them, they can use the memory without any setup |
| 87 | * work. When it can't, they have to clear the area. |
| 88 | * |
| 89 | * - These buffers also have different alignment requirements. |
| 90 | * |
| 91 | * - We would like to reuse the objects in the workspace for multiple |
| 92 | * compressions without having to perform any expensive reallocation or |
| 93 | * reinitialization work. |
| 94 | * |
| 95 | * - We would like to be able to efficiently reuse the workspace across |
| 96 | * multiple compressions **even when the compression parameters change** and |
| 97 | * we need to resize some of the objects (where possible). |
| 98 | * |
| 99 | * To attempt to manage this buffer, given these constraints, the ZSTD_cwksp |
| 100 | * abstraction was created. It works as follows: |
| 101 | * |
| 102 | * Workspace Layout: |
| 103 | * |
| 104 | * [ ... workspace ... ] |
| 105 | * [objects][tables ->] free space [<- buffers][<- aligned][<- init once] |
| 106 | * |
| 107 | * The various objects that live in the workspace are divided into the |
| 108 | * following categories, and are allocated separately: |
| 109 | * |
| 110 | * - Static objects: this is optionally the enclosing ZSTD_CCtx or ZSTD_CDict, |
| 111 | * so that literally everything fits in a single buffer. Note: if present, |
| 112 | * this must be the first object in the workspace, since ZSTD_customFree{CCtx, |
| 113 | * CDict}() rely on a pointer comparison to see whether one or two frees are |
| 114 | * required. |
| 115 | * |
| 116 | * - Fixed size objects: these are fixed-size, fixed-count objects that are |
| 117 | * nonetheless "dynamically" allocated in the workspace so that we can |
| 118 | * control how they're initialized separately from the broader ZSTD_CCtx. |
| 119 | * Examples: |
| 120 | * - Entropy Workspace |
| 121 | * - 2 x ZSTD_compressedBlockState_t |
| 122 | * - CDict dictionary contents |
| 123 | * |
| 124 | * - Tables: these are any of several different datastructures (hash tables, |
| 125 | * chain tables, binary trees) that all respect a common format: they are |
| 126 | * uint32_t arrays, all of whose values are between 0 and (nextSrc - base). |
| 127 | * Their sizes depend on the cparams. These tables are 64-byte aligned. |
| 128 | * |
| 129 | * - Init once: these buffers require to be initialized at least once before |
| 130 | * use. They should be used when we want to skip memory initialization |
| 131 | * while not triggering memory checkers (like Valgrind) when reading from |
| 132 | * from this memory without writing to it first. |
| 133 | * These buffers should be used carefully as they might contain data |
| 134 | * from previous compressions. |
| 135 | * Buffers are aligned to 64 bytes. |
| 136 | * |
| 137 | * - Aligned: these buffers don't require any initialization before they're |
| 138 | * used. The user of the buffer should make sure they write into a buffer |
| 139 | * location before reading from it. |
| 140 | * Buffers are aligned to 64 bytes. |
| 141 | * |
| 142 | * - Buffers: these buffers are used for various purposes that don't require |
| 143 | * any alignment or initialization before they're used. This means they can |
| 144 | * be moved around at no cost for a new compression. |
| 145 | * |
| 146 | * Allocating Memory: |
| 147 | * |
| 148 | * The various types of objects must be allocated in order, so they can be |
| 149 | * correctly packed into the workspace buffer. That order is: |
| 150 | * |
| 151 | * 1. Objects |
| 152 | * 2. Init once / Tables |
| 153 | * 3. Aligned / Tables |
| 154 | * 4. Buffers / Tables |
| 155 | * |
| 156 | * Attempts to reserve objects of different types out of order will fail. |
| 157 | */ |
| 158 | typedef struct { |
| 159 | void* workspace; |
| 160 | void* workspaceEnd; |
| 161 | |
| 162 | void* objectEnd; |
| 163 | void* tableEnd; |
| 164 | void* tableValidEnd; |
| 165 | void* allocStart; |
| 166 | void* initOnceStart; |
| 167 | |
| 168 | BYTE allocFailed; |
| 169 | int workspaceOversizedDuration; |
| 170 | ZSTD_cwksp_alloc_phase_e phase; |
| 171 | ZSTD_cwksp_static_alloc_e isStatic; |
| 172 | } ZSTD_cwksp; |
| 173 | |
| 174 | /*-************************************* |
| 175 | * Functions |
| 176 | ***************************************/ |
| 177 | |
| 178 | MEM_STATIC size_t ZSTD_cwksp_available_space(ZSTD_cwksp* ws); |
| 179 | MEM_STATIC void* ZSTD_cwksp_initialAllocStart(ZSTD_cwksp* ws); |
| 180 | |
| 181 | MEM_STATIC void ZSTD_cwksp_assert_internal_consistency(ZSTD_cwksp* ws) { |
| 182 | (void)ws; |
| 183 | assert(ws->workspace <= ws->objectEnd); |
| 184 | assert(ws->objectEnd <= ws->tableEnd); |
| 185 | assert(ws->objectEnd <= ws->tableValidEnd); |
| 186 | assert(ws->tableEnd <= ws->allocStart); |
| 187 | assert(ws->tableValidEnd <= ws->allocStart); |
| 188 | assert(ws->allocStart <= ws->workspaceEnd); |
| 189 | assert(ws->initOnceStart <= ZSTD_cwksp_initialAllocStart(ws)); |
| 190 | assert(ws->workspace <= ws->initOnceStart); |
| 191 | #if ZSTD_MEMORY_SANITIZER |
| 192 | { |
| 193 | intptr_t const offset = __msan_test_shadow(ws->initOnceStart, |
| 194 | (U8*)ZSTD_cwksp_initialAllocStart(ws) - (U8*)ws->initOnceStart); |
| 195 | #if defined(ZSTD_MSAN_PRINT) |
| 196 | if(offset!=-1) { |
| 197 | __msan_print_shadow((U8*)ws->initOnceStart + offset - 8, 32); |
| 198 | } |
| 199 | #endif |
| 200 | assert(offset==-1); |
| 201 | }; |
| 202 | #endif |
| 203 | } |
| 204 | |
| 205 | /** |
| 206 | * Align must be a power of 2. |
| 207 | */ |
| 208 | MEM_STATIC size_t ZSTD_cwksp_align(size_t size, size_t const align) { |
| 209 | size_t const mask = align - 1; |
| 210 | assert((align & mask) == 0); |
| 211 | return (size + mask) & ~mask; |
| 212 | } |
| 213 | |
| 214 | /** |
| 215 | * Use this to determine how much space in the workspace we will consume to |
| 216 | * allocate this object. (Normally it should be exactly the size of the object, |
| 217 | * but under special conditions, like ASAN, where we pad each object, it might |
| 218 | * be larger.) |
| 219 | * |
| 220 | * Since tables aren't currently redzoned, you don't need to call through this |
| 221 | * to figure out how much space you need for the matchState tables. Everything |
| 222 | * else is though. |
| 223 | * |
| 224 | * Do not use for sizing aligned buffers. Instead, use ZSTD_cwksp_aligned_alloc_size(). |
| 225 | */ |
| 226 | MEM_STATIC size_t ZSTD_cwksp_alloc_size(size_t size) { |
| 227 | if (size == 0) |
| 228 | return 0; |
| 229 | #if ZSTD_ADDRESS_SANITIZER && !defined (ZSTD_ASAN_DONT_POISON_WORKSPACE) |
| 230 | return size + 2 * ZSTD_CWKSP_ASAN_REDZONE_SIZE; |
| 231 | #else |
| 232 | return size; |
| 233 | #endif |
| 234 | } |
| 235 | |
| 236 | /** |
| 237 | * Returns an adjusted alloc size that is the nearest larger multiple of 64 bytes. |
| 238 | * Used to determine the number of bytes required for a given "aligned". |
| 239 | */ |
| 240 | MEM_STATIC size_t ZSTD_cwksp_aligned_alloc_size(size_t size) { |
| 241 | return ZSTD_cwksp_alloc_size(ZSTD_cwksp_align(size, ZSTD_CWKSP_ALIGNMENT_BYTES)); |
| 242 | } |
| 243 | |
| 244 | /** |
| 245 | * Returns the amount of additional space the cwksp must allocate |
| 246 | * for internal purposes (currently only alignment). |
| 247 | */ |
| 248 | MEM_STATIC size_t ZSTD_cwksp_slack_space_required(void) { |
| 249 | /* For alignment, the wksp will always allocate an additional 2*ZSTD_CWKSP_ALIGNMENT_BYTES |
| 250 | * bytes to align the beginning of tables section and end of buffers; |
| 251 | */ |
| 252 | size_t const slackSpace = ZSTD_CWKSP_ALIGNMENT_BYTES * 2; |
| 253 | return slackSpace; |
| 254 | } |
| 255 | |
| 256 | |
| 257 | /** |
| 258 | * Return the number of additional bytes required to align a pointer to the given number of bytes. |
| 259 | * alignBytes must be a power of two. |
| 260 | */ |
| 261 | MEM_STATIC size_t ZSTD_cwksp_bytes_to_align_ptr(void* ptr, const size_t alignBytes) { |
| 262 | size_t const alignBytesMask = alignBytes - 1; |
| 263 | size_t const bytes = (alignBytes - ((size_t)ptr & (alignBytesMask))) & alignBytesMask; |
| 264 | assert((alignBytes & alignBytesMask) == 0); |
| 265 | assert(bytes < alignBytes); |
| 266 | return bytes; |
| 267 | } |
| 268 | |
| 269 | /** |
| 270 | * Returns the initial value for allocStart which is used to determine the position from |
| 271 | * which we can allocate from the end of the workspace. |
| 272 | */ |
| 273 | MEM_STATIC void* ZSTD_cwksp_initialAllocStart(ZSTD_cwksp* ws) { |
| 274 | return (void*)((size_t)ws->workspaceEnd & ~(ZSTD_CWKSP_ALIGNMENT_BYTES-1)); |
| 275 | } |
| 276 | |
| 277 | /** |
| 278 | * Internal function. Do not use directly. |
| 279 | * Reserves the given number of bytes within the aligned/buffer segment of the wksp, |
| 280 | * which counts from the end of the wksp (as opposed to the object/table segment). |
| 281 | * |
| 282 | * Returns a pointer to the beginning of that space. |
| 283 | */ |
| 284 | MEM_STATIC void* |
| 285 | ZSTD_cwksp_reserve_internal_buffer_space(ZSTD_cwksp* ws, size_t const bytes) |
| 286 | { |
| 287 | void* const alloc = (BYTE*)ws->allocStart - bytes; |
| 288 | void* const bottom = ws->tableEnd; |
| 289 | DEBUGLOG(5, "cwksp: reserving %p %zd bytes, %zd bytes remaining", |
| 290 | alloc, bytes, ZSTD_cwksp_available_space(ws) - bytes); |
| 291 | ZSTD_cwksp_assert_internal_consistency(ws); |
| 292 | assert(alloc >= bottom); |
| 293 | if (alloc < bottom) { |
| 294 | DEBUGLOG(4, "cwksp: alloc failed!"); |
| 295 | ws->allocFailed = 1; |
| 296 | return NULL; |
| 297 | } |
| 298 | /* the area is reserved from the end of wksp. |
| 299 | * If it overlaps with tableValidEnd, it voids guarantees on values' range */ |
| 300 | if (alloc < ws->tableValidEnd) { |
| 301 | ws->tableValidEnd = alloc; |
| 302 | } |
| 303 | ws->allocStart = alloc; |
| 304 | return alloc; |
| 305 | } |
| 306 | |
| 307 | /** |
| 308 | * Moves the cwksp to the next phase, and does any necessary allocations. |
| 309 | * cwksp initialization must necessarily go through each phase in order. |
| 310 | * Returns a 0 on success, or zstd error |
| 311 | */ |
| 312 | MEM_STATIC size_t |
| 313 | ZSTD_cwksp_internal_advance_phase(ZSTD_cwksp* ws, ZSTD_cwksp_alloc_phase_e phase) |
| 314 | { |
| 315 | assert(phase >= ws->phase); |
| 316 | if (phase > ws->phase) { |
| 317 | /* Going from allocating objects to allocating initOnce / tables */ |
| 318 | if (ws->phase < ZSTD_cwksp_alloc_aligned_init_once && |
| 319 | phase >= ZSTD_cwksp_alloc_aligned_init_once) { |
| 320 | ws->tableValidEnd = ws->objectEnd; |
| 321 | ws->initOnceStart = ZSTD_cwksp_initialAllocStart(ws); |
| 322 | |
| 323 | { /* Align the start of the tables to 64 bytes. Use [0, 63] bytes */ |
| 324 | void *const alloc = ws->objectEnd; |
| 325 | size_t const bytesToAlign = ZSTD_cwksp_bytes_to_align_ptr(alloc, ZSTD_CWKSP_ALIGNMENT_BYTES); |
| 326 | void *const objectEnd = (BYTE *) alloc + bytesToAlign; |
| 327 | DEBUGLOG(5, "reserving table alignment addtl space: %zu", bytesToAlign); |
| 328 | RETURN_ERROR_IF(objectEnd > ws->workspaceEnd, memory_allocation, |
| 329 | "table phase - alignment initial allocation failed!"); |
| 330 | ws->objectEnd = objectEnd; |
| 331 | ws->tableEnd = objectEnd; /* table area starts being empty */ |
| 332 | if (ws->tableValidEnd < ws->tableEnd) { |
| 333 | ws->tableValidEnd = ws->tableEnd; |
| 334 | } |
| 335 | } |
| 336 | } |
| 337 | ws->phase = phase; |
| 338 | ZSTD_cwksp_assert_internal_consistency(ws); |
| 339 | } |
| 340 | return 0; |
| 341 | } |
| 342 | |
| 343 | /** |
| 344 | * Returns whether this object/buffer/etc was allocated in this workspace. |
| 345 | */ |
| 346 | MEM_STATIC int ZSTD_cwksp_owns_buffer(const ZSTD_cwksp* ws, const void* ptr) |
| 347 | { |
| 348 | return (ptr != NULL) && (ws->workspace <= ptr) && (ptr < ws->workspaceEnd); |
| 349 | } |
| 350 | |
| 351 | /** |
| 352 | * Internal function. Do not use directly. |
| 353 | */ |
| 354 | MEM_STATIC void* |
| 355 | ZSTD_cwksp_reserve_internal(ZSTD_cwksp* ws, size_t bytes, ZSTD_cwksp_alloc_phase_e phase) |
| 356 | { |
| 357 | void* alloc; |
| 358 | if (ZSTD_isError(ZSTD_cwksp_internal_advance_phase(ws, phase)) || bytes == 0) { |
| 359 | return NULL; |
| 360 | } |
| 361 | |
| 362 | #if ZSTD_ADDRESS_SANITIZER && !defined (ZSTD_ASAN_DONT_POISON_WORKSPACE) |
| 363 | /* over-reserve space */ |
| 364 | bytes += 2 * ZSTD_CWKSP_ASAN_REDZONE_SIZE; |
| 365 | #endif |
| 366 | |
| 367 | alloc = ZSTD_cwksp_reserve_internal_buffer_space(ws, bytes); |
| 368 | |
| 369 | #if ZSTD_ADDRESS_SANITIZER && !defined (ZSTD_ASAN_DONT_POISON_WORKSPACE) |
| 370 | /* Move alloc so there's ZSTD_CWKSP_ASAN_REDZONE_SIZE unused space on |
| 371 | * either size. */ |
| 372 | if (alloc) { |
| 373 | alloc = (BYTE *)alloc + ZSTD_CWKSP_ASAN_REDZONE_SIZE; |
| 374 | if (ws->isStatic == ZSTD_cwksp_dynamic_alloc) { |
| 375 | /* We need to keep the redzone poisoned while unpoisoning the bytes that |
| 376 | * are actually allocated. */ |
| 377 | __asan_unpoison_memory_region(alloc, bytes - 2 * ZSTD_CWKSP_ASAN_REDZONE_SIZE); |
| 378 | } |
| 379 | } |
| 380 | #endif |
| 381 | |
| 382 | return alloc; |
| 383 | } |
| 384 | |
| 385 | /** |
| 386 | * Reserves and returns unaligned memory. |
| 387 | */ |
| 388 | MEM_STATIC BYTE* ZSTD_cwksp_reserve_buffer(ZSTD_cwksp* ws, size_t bytes) |
| 389 | { |
| 390 | return (BYTE*)ZSTD_cwksp_reserve_internal(ws, bytes, ZSTD_cwksp_alloc_buffers); |
| 391 | } |
| 392 | |
| 393 | /** |
| 394 | * Reserves and returns memory sized on and aligned on ZSTD_CWKSP_ALIGNMENT_BYTES (64 bytes). |
| 395 | * This memory has been initialized at least once in the past. |
| 396 | * This doesn't mean it has been initialized this time, and it might contain data from previous |
| 397 | * operations. |
| 398 | * The main usage is for algorithms that might need read access into uninitialized memory. |
| 399 | * The algorithm must maintain safety under these conditions and must make sure it doesn't |
| 400 | * leak any of the past data (directly or in side channels). |
| 401 | */ |
| 402 | MEM_STATIC void* ZSTD_cwksp_reserve_aligned_init_once(ZSTD_cwksp* ws, size_t bytes) |
| 403 | { |
| 404 | size_t const alignedBytes = ZSTD_cwksp_align(bytes, ZSTD_CWKSP_ALIGNMENT_BYTES); |
| 405 | void* ptr = ZSTD_cwksp_reserve_internal(ws, alignedBytes, ZSTD_cwksp_alloc_aligned_init_once); |
| 406 | assert(((size_t)ptr & (ZSTD_CWKSP_ALIGNMENT_BYTES-1))== 0); |
| 407 | if(ptr && ptr < ws->initOnceStart) { |
| 408 | /* We assume the memory following the current allocation is either: |
| 409 | * 1. Not usable as initOnce memory (end of workspace) |
| 410 | * 2. Another initOnce buffer that has been allocated before (and so was previously memset) |
| 411 | * 3. An ASAN redzone, in which case we don't want to write on it |
| 412 | * For these reasons it should be fine to not explicitly zero every byte up to ws->initOnceStart. |
| 413 | * Note that we assume here that MSAN and ASAN cannot run in the same time. */ |
| 414 | ZSTD_memset(ptr, 0, MIN((size_t)((U8*)ws->initOnceStart - (U8*)ptr), alignedBytes)); |
| 415 | ws->initOnceStart = ptr; |
| 416 | } |
| 417 | #if ZSTD_MEMORY_SANITIZER |
| 418 | assert(__msan_test_shadow(ptr, bytes) == -1); |
| 419 | #endif |
| 420 | return ptr; |
| 421 | } |
| 422 | |
| 423 | /** |
| 424 | * Reserves and returns memory sized on and aligned on ZSTD_CWKSP_ALIGNMENT_BYTES (64 bytes). |
| 425 | */ |
| 426 | MEM_STATIC void* ZSTD_cwksp_reserve_aligned(ZSTD_cwksp* ws, size_t bytes) |
| 427 | { |
| 428 | void* ptr = ZSTD_cwksp_reserve_internal(ws, ZSTD_cwksp_align(bytes, ZSTD_CWKSP_ALIGNMENT_BYTES), |
| 429 | ZSTD_cwksp_alloc_aligned); |
| 430 | assert(((size_t)ptr & (ZSTD_CWKSP_ALIGNMENT_BYTES-1))== 0); |
| 431 | return ptr; |
| 432 | } |
| 433 | |
| 434 | /** |
| 435 | * Aligned on 64 bytes. These buffers have the special property that |
| 436 | * their values remain constrained, allowing us to re-use them without |
| 437 | * memset()-ing them. |
| 438 | */ |
| 439 | MEM_STATIC void* ZSTD_cwksp_reserve_table(ZSTD_cwksp* ws, size_t bytes) |
| 440 | { |
| 441 | const ZSTD_cwksp_alloc_phase_e phase = ZSTD_cwksp_alloc_aligned_init_once; |
| 442 | void* alloc; |
| 443 | void* end; |
| 444 | void* top; |
| 445 | |
| 446 | /* We can only start allocating tables after we are done reserving space for objects at the |
| 447 | * start of the workspace */ |
| 448 | if(ws->phase < phase) { |
| 449 | if (ZSTD_isError(ZSTD_cwksp_internal_advance_phase(ws, phase))) { |
| 450 | return NULL; |
| 451 | } |
| 452 | } |
| 453 | alloc = ws->tableEnd; |
| 454 | end = (BYTE *)alloc + bytes; |
| 455 | top = ws->allocStart; |
| 456 | |
| 457 | DEBUGLOG(5, "cwksp: reserving %p table %zd bytes, %zd bytes remaining", |
| 458 | alloc, bytes, ZSTD_cwksp_available_space(ws) - bytes); |
| 459 | assert((bytes & (sizeof(U32)-1)) == 0); |
| 460 | ZSTD_cwksp_assert_internal_consistency(ws); |
| 461 | assert(end <= top); |
| 462 | if (end > top) { |
| 463 | DEBUGLOG(4, "cwksp: table alloc failed!"); |
| 464 | ws->allocFailed = 1; |
| 465 | return NULL; |
| 466 | } |
| 467 | ws->tableEnd = end; |
| 468 | |
| 469 | #if ZSTD_ADDRESS_SANITIZER && !defined (ZSTD_ASAN_DONT_POISON_WORKSPACE) |
| 470 | if (ws->isStatic == ZSTD_cwksp_dynamic_alloc) { |
| 471 | __asan_unpoison_memory_region(alloc, bytes); |
| 472 | } |
| 473 | #endif |
| 474 | |
| 475 | assert((bytes & (ZSTD_CWKSP_ALIGNMENT_BYTES-1)) == 0); |
| 476 | assert(((size_t)alloc & (ZSTD_CWKSP_ALIGNMENT_BYTES-1))== 0); |
| 477 | return alloc; |
| 478 | } |
| 479 | |
| 480 | /** |
| 481 | * Aligned on sizeof(void*). |
| 482 | * Note : should happen only once, at workspace first initialization |
| 483 | */ |
| 484 | MEM_STATIC void* ZSTD_cwksp_reserve_object(ZSTD_cwksp* ws, size_t bytes) |
| 485 | { |
| 486 | size_t const roundedBytes = ZSTD_cwksp_align(bytes, sizeof(void*)); |
| 487 | void* alloc = ws->objectEnd; |
| 488 | void* end = (BYTE*)alloc + roundedBytes; |
| 489 | |
| 490 | #if ZSTD_ADDRESS_SANITIZER && !defined (ZSTD_ASAN_DONT_POISON_WORKSPACE) |
| 491 | /* over-reserve space */ |
| 492 | end = (BYTE *)end + 2 * ZSTD_CWKSP_ASAN_REDZONE_SIZE; |
| 493 | #endif |
| 494 | |
| 495 | DEBUGLOG(4, |
| 496 | "cwksp: reserving %p object %zd bytes (rounded to %zd), %zd bytes remaining", |
| 497 | alloc, bytes, roundedBytes, ZSTD_cwksp_available_space(ws) - roundedBytes); |
| 498 | assert((size_t)alloc % ZSTD_ALIGNOF(void*) == 0); |
| 499 | assert(bytes % ZSTD_ALIGNOF(void*) == 0); |
| 500 | ZSTD_cwksp_assert_internal_consistency(ws); |
| 501 | /* we must be in the first phase, no advance is possible */ |
| 502 | if (ws->phase != ZSTD_cwksp_alloc_objects || end > ws->workspaceEnd) { |
| 503 | DEBUGLOG(3, "cwksp: object alloc failed!"); |
| 504 | ws->allocFailed = 1; |
| 505 | return NULL; |
| 506 | } |
| 507 | ws->objectEnd = end; |
| 508 | ws->tableEnd = end; |
| 509 | ws->tableValidEnd = end; |
| 510 | |
| 511 | #if ZSTD_ADDRESS_SANITIZER && !defined (ZSTD_ASAN_DONT_POISON_WORKSPACE) |
| 512 | /* Move alloc so there's ZSTD_CWKSP_ASAN_REDZONE_SIZE unused space on |
| 513 | * either size. */ |
| 514 | alloc = (BYTE*)alloc + ZSTD_CWKSP_ASAN_REDZONE_SIZE; |
| 515 | if (ws->isStatic == ZSTD_cwksp_dynamic_alloc) { |
| 516 | __asan_unpoison_memory_region(alloc, bytes); |
| 517 | } |
| 518 | #endif |
| 519 | |
| 520 | return alloc; |
| 521 | } |
| 522 | |
| 523 | MEM_STATIC void ZSTD_cwksp_mark_tables_dirty(ZSTD_cwksp* ws) |
| 524 | { |
| 525 | DEBUGLOG(4, "cwksp: ZSTD_cwksp_mark_tables_dirty"); |
| 526 | |
| 527 | #if ZSTD_MEMORY_SANITIZER && !defined (ZSTD_MSAN_DONT_POISON_WORKSPACE) |
| 528 | /* To validate that the table re-use logic is sound, and that we don't |
| 529 | * access table space that we haven't cleaned, we re-"poison" the table |
| 530 | * space every time we mark it dirty. |
| 531 | * Since tableValidEnd space and initOnce space may overlap we don't poison |
| 532 | * the initOnce portion as it break its promise. This means that this poisoning |
| 533 | * check isn't always applied fully. */ |
| 534 | { |
| 535 | size_t size = (BYTE*)ws->tableValidEnd - (BYTE*)ws->objectEnd; |
| 536 | assert(__msan_test_shadow(ws->objectEnd, size) == -1); |
| 537 | if((BYTE*)ws->tableValidEnd < (BYTE*)ws->initOnceStart) { |
| 538 | __msan_poison(ws->objectEnd, size); |
| 539 | } else { |
| 540 | assert(ws->initOnceStart >= ws->objectEnd); |
| 541 | __msan_poison(ws->objectEnd, (BYTE*)ws->initOnceStart - (BYTE*)ws->objectEnd); |
| 542 | } |
| 543 | } |
| 544 | #endif |
| 545 | |
| 546 | assert(ws->tableValidEnd >= ws->objectEnd); |
| 547 | assert(ws->tableValidEnd <= ws->allocStart); |
| 548 | ws->tableValidEnd = ws->objectEnd; |
| 549 | ZSTD_cwksp_assert_internal_consistency(ws); |
| 550 | } |
| 551 | |
| 552 | MEM_STATIC void ZSTD_cwksp_mark_tables_clean(ZSTD_cwksp* ws) { |
| 553 | DEBUGLOG(4, "cwksp: ZSTD_cwksp_mark_tables_clean"); |
| 554 | assert(ws->tableValidEnd >= ws->objectEnd); |
| 555 | assert(ws->tableValidEnd <= ws->allocStart); |
| 556 | if (ws->tableValidEnd < ws->tableEnd) { |
| 557 | ws->tableValidEnd = ws->tableEnd; |
| 558 | } |
| 559 | ZSTD_cwksp_assert_internal_consistency(ws); |
| 560 | } |
| 561 | |
| 562 | /** |
| 563 | * Zero the part of the allocated tables not already marked clean. |
| 564 | */ |
| 565 | MEM_STATIC void ZSTD_cwksp_clean_tables(ZSTD_cwksp* ws) { |
| 566 | DEBUGLOG(4, "cwksp: ZSTD_cwksp_clean_tables"); |
| 567 | assert(ws->tableValidEnd >= ws->objectEnd); |
| 568 | assert(ws->tableValidEnd <= ws->allocStart); |
| 569 | if (ws->tableValidEnd < ws->tableEnd) { |
| 570 | ZSTD_memset(ws->tableValidEnd, 0, (size_t)((BYTE*)ws->tableEnd - (BYTE*)ws->tableValidEnd)); |
| 571 | } |
| 572 | ZSTD_cwksp_mark_tables_clean(ws); |
| 573 | } |
| 574 | |
| 575 | /** |
| 576 | * Invalidates table allocations. |
| 577 | * All other allocations remain valid. |
| 578 | */ |
| 579 | MEM_STATIC void ZSTD_cwksp_clear_tables(ZSTD_cwksp* ws) { |
| 580 | DEBUGLOG(4, "cwksp: clearing tables!"); |
| 581 | |
| 582 | #if ZSTD_ADDRESS_SANITIZER && !defined (ZSTD_ASAN_DONT_POISON_WORKSPACE) |
| 583 | /* We don't do this when the workspace is statically allocated, because |
| 584 | * when that is the case, we have no capability to hook into the end of the |
| 585 | * workspace's lifecycle to unpoison the memory. |
| 586 | */ |
| 587 | if (ws->isStatic == ZSTD_cwksp_dynamic_alloc) { |
| 588 | size_t size = (BYTE*)ws->tableValidEnd - (BYTE*)ws->objectEnd; |
| 589 | __asan_poison_memory_region(ws->objectEnd, size); |
| 590 | } |
| 591 | #endif |
| 592 | |
| 593 | ws->tableEnd = ws->objectEnd; |
| 594 | ZSTD_cwksp_assert_internal_consistency(ws); |
| 595 | } |
| 596 | |
| 597 | /** |
| 598 | * Invalidates all buffer, aligned, and table allocations. |
| 599 | * Object allocations remain valid. |
| 600 | */ |
| 601 | MEM_STATIC void ZSTD_cwksp_clear(ZSTD_cwksp* ws) { |
| 602 | DEBUGLOG(4, "cwksp: clearing!"); |
| 603 | |
| 604 | #if ZSTD_MEMORY_SANITIZER && !defined (ZSTD_MSAN_DONT_POISON_WORKSPACE) |
| 605 | /* To validate that the context re-use logic is sound, and that we don't |
| 606 | * access stuff that this compression hasn't initialized, we re-"poison" |
| 607 | * the workspace except for the areas in which we expect memory re-use |
| 608 | * without initialization (objects, valid tables area and init once |
| 609 | * memory). */ |
| 610 | { |
| 611 | if((BYTE*)ws->tableValidEnd < (BYTE*)ws->initOnceStart) { |
| 612 | size_t size = (BYTE*)ws->initOnceStart - (BYTE*)ws->tableValidEnd; |
| 613 | __msan_poison(ws->tableValidEnd, size); |
| 614 | } |
| 615 | } |
| 616 | #endif |
| 617 | |
| 618 | #if ZSTD_ADDRESS_SANITIZER && !defined (ZSTD_ASAN_DONT_POISON_WORKSPACE) |
| 619 | /* We don't do this when the workspace is statically allocated, because |
| 620 | * when that is the case, we have no capability to hook into the end of the |
| 621 | * workspace's lifecycle to unpoison the memory. |
| 622 | */ |
| 623 | if (ws->isStatic == ZSTD_cwksp_dynamic_alloc) { |
| 624 | size_t size = (BYTE*)ws->workspaceEnd - (BYTE*)ws->objectEnd; |
| 625 | __asan_poison_memory_region(ws->objectEnd, size); |
| 626 | } |
| 627 | #endif |
| 628 | |
| 629 | ws->tableEnd = ws->objectEnd; |
| 630 | ws->allocStart = ZSTD_cwksp_initialAllocStart(ws); |
| 631 | ws->allocFailed = 0; |
| 632 | if (ws->phase > ZSTD_cwksp_alloc_aligned_init_once) { |
| 633 | ws->phase = ZSTD_cwksp_alloc_aligned_init_once; |
| 634 | } |
| 635 | ZSTD_cwksp_assert_internal_consistency(ws); |
| 636 | } |
| 637 | |
| 638 | /** |
| 639 | * The provided workspace takes ownership of the buffer [start, start+size). |
| 640 | * Any existing values in the workspace are ignored (the previously managed |
| 641 | * buffer, if present, must be separately freed). |
| 642 | */ |
| 643 | MEM_STATIC void ZSTD_cwksp_init(ZSTD_cwksp* ws, void* start, size_t size, ZSTD_cwksp_static_alloc_e isStatic) { |
| 644 | DEBUGLOG(4, "cwksp: init'ing workspace with %zd bytes", size); |
| 645 | assert(((size_t)start & (sizeof(void*)-1)) == 0); /* ensure correct alignment */ |
| 646 | ws->workspace = start; |
| 647 | ws->workspaceEnd = (BYTE*)start + size; |
| 648 | ws->objectEnd = ws->workspace; |
| 649 | ws->tableValidEnd = ws->objectEnd; |
| 650 | ws->initOnceStart = ZSTD_cwksp_initialAllocStart(ws); |
| 651 | ws->phase = ZSTD_cwksp_alloc_objects; |
| 652 | ws->isStatic = isStatic; |
| 653 | ZSTD_cwksp_clear(ws); |
| 654 | ws->workspaceOversizedDuration = 0; |
| 655 | ZSTD_cwksp_assert_internal_consistency(ws); |
| 656 | } |
| 657 | |
| 658 | MEM_STATIC size_t ZSTD_cwksp_create(ZSTD_cwksp* ws, size_t size, ZSTD_customMem customMem) { |
| 659 | void* workspace = ZSTD_customMalloc(size, customMem); |
| 660 | DEBUGLOG(4, "cwksp: creating new workspace with %zd bytes", size); |
| 661 | RETURN_ERROR_IF(workspace == NULL, memory_allocation, "NULL pointer!"); |
| 662 | ZSTD_cwksp_init(ws, workspace, size, ZSTD_cwksp_dynamic_alloc); |
| 663 | return 0; |
| 664 | } |
| 665 | |
| 666 | MEM_STATIC void ZSTD_cwksp_free(ZSTD_cwksp* ws, ZSTD_customMem customMem) { |
| 667 | void *ptr = ws->workspace; |
| 668 | DEBUGLOG(4, "cwksp: freeing workspace"); |
| 669 | ZSTD_memset(ws, 0, sizeof(ZSTD_cwksp)); |
| 670 | ZSTD_customFree(ptr, customMem); |
| 671 | } |
| 672 | |
| 673 | /** |
| 674 | * Moves the management of a workspace from one cwksp to another. The src cwksp |
| 675 | * is left in an invalid state (src must be re-init()'ed before it's used again). |
| 676 | */ |
| 677 | MEM_STATIC void ZSTD_cwksp_move(ZSTD_cwksp* dst, ZSTD_cwksp* src) { |
| 678 | *dst = *src; |
| 679 | ZSTD_memset(src, 0, sizeof(ZSTD_cwksp)); |
| 680 | } |
| 681 | |
| 682 | MEM_STATIC size_t ZSTD_cwksp_sizeof(const ZSTD_cwksp* ws) { |
| 683 | return (size_t)((BYTE*)ws->workspaceEnd - (BYTE*)ws->workspace); |
| 684 | } |
| 685 | |
| 686 | MEM_STATIC size_t ZSTD_cwksp_used(const ZSTD_cwksp* ws) { |
| 687 | return (size_t)((BYTE*)ws->tableEnd - (BYTE*)ws->workspace) |
| 688 | + (size_t)((BYTE*)ws->workspaceEnd - (BYTE*)ws->allocStart); |
| 689 | } |
| 690 | |
| 691 | MEM_STATIC int ZSTD_cwksp_reserve_failed(const ZSTD_cwksp* ws) { |
| 692 | return ws->allocFailed; |
| 693 | } |
| 694 | |
| 695 | /*-************************************* |
| 696 | * Functions Checking Free Space |
| 697 | ***************************************/ |
| 698 | |
| 699 | /* ZSTD_alignmentSpaceWithinBounds() : |
| 700 | * Returns if the estimated space needed for a wksp is within an acceptable limit of the |
| 701 | * actual amount of space used. |
| 702 | */ |
| 703 | MEM_STATIC int ZSTD_cwksp_estimated_space_within_bounds(const ZSTD_cwksp *const ws, size_t const estimatedSpace) { |
| 704 | /* We have an alignment space between objects and tables between tables and buffers, so we can have up to twice |
| 705 | * the alignment bytes difference between estimation and actual usage */ |
| 706 | return (estimatedSpace - ZSTD_cwksp_slack_space_required()) <= ZSTD_cwksp_used(ws) && |
| 707 | ZSTD_cwksp_used(ws) <= estimatedSpace; |
| 708 | } |
| 709 | |
| 710 | |
| 711 | MEM_STATIC size_t ZSTD_cwksp_available_space(ZSTD_cwksp* ws) { |
| 712 | return (size_t)((BYTE*)ws->allocStart - (BYTE*)ws->tableEnd); |
| 713 | } |
| 714 | |
| 715 | MEM_STATIC int ZSTD_cwksp_check_available(ZSTD_cwksp* ws, size_t additionalNeededSpace) { |
| 716 | return ZSTD_cwksp_available_space(ws) >= additionalNeededSpace; |
| 717 | } |
| 718 | |
| 719 | MEM_STATIC int ZSTD_cwksp_check_too_large(ZSTD_cwksp* ws, size_t additionalNeededSpace) { |
| 720 | return ZSTD_cwksp_check_available( |
| 721 | ws, additionalNeededSpace * ZSTD_WORKSPACETOOLARGE_FACTOR); |
| 722 | } |
| 723 | |
| 724 | MEM_STATIC int ZSTD_cwksp_check_wasteful(ZSTD_cwksp* ws, size_t additionalNeededSpace) { |
| 725 | return ZSTD_cwksp_check_too_large(ws, additionalNeededSpace) |
| 726 | && ws->workspaceOversizedDuration > ZSTD_WORKSPACETOOLARGE_MAXDURATION; |
| 727 | } |
| 728 | |
| 729 | MEM_STATIC void ZSTD_cwksp_bump_oversized_duration( |
| 730 | ZSTD_cwksp* ws, size_t additionalNeededSpace) { |
| 731 | if (ZSTD_cwksp_check_too_large(ws, additionalNeededSpace)) { |
| 732 | ws->workspaceOversizedDuration++; |
| 733 | } else { |
| 734 | ws->workspaceOversizedDuration = 0; |
| 735 | } |
| 736 | } |
| 737 | |
| 738 | #if defined (__cplusplus) |
| 739 | } |
| 740 | #endif |
| 741 | |
| 742 | #endif /* ZSTD_CWKSP_H */ |