include/exec/ram_addr.h

   1 /*
   2  * Declarations for cpu physical memory functions
   3  *
   4  * Copyright 2011 Red Hat, Inc. and/or its affiliates
   5  *
   6  * Authors:
   7  *  Avi Kivity <avi@redhat.com>
   8  *
   9  * This work is licensed under the terms of the GNU GPL, version 2 or
  10  * later.  See the COPYING file in the top-level directory.
  11  *
  12  */
  13
  14 /*
  15  * This header is for use by exec.c and memory.c ONLY.  Do not include it.
  16  * The functions declared here will be removed soon.
  17  */
  18
  19 #ifndef RAM_ADDR_H
  20 #define RAM_ADDR_H
  21
  22 #ifndef CONFIG_USER_ONLY
  23 #include "cpu.h"
  24 #include "sysemu/xen.h"
  25 #include "sysemu/tcg.h"
  26 #include "exec/ramlist.h"
  27 #include "exec/ramblock.h"
  28
  29 extern uint64_t total_dirty_pages;
  30
  31 /**
  32  * clear_bmap_size: calculate clear bitmap size
  33  *
  34  * @pages: number of guest pages
  35  * @shift: guest page number shift
  36  *
  37  * Returns: number of bits for the clear bitmap
  38  */
  39 static inline long clear_bmap_size(uint64_t pages, uint8_t shift)
  40 {
  41     return DIV_ROUND_UP(pages, 1UL << shift);
  42 }
  43
  44 /**
  45  * clear_bmap_set: set clear bitmap for the page range
  46  *
  47  * @rb: the ramblock to operate on
  48  * @start: the start page number
  49  * @size: number of pages to set in the bitmap
  50  *
  51  * Returns: None
  52  */
  53 static inline void clear_bmap_set(RAMBlock *rb, uint64_t start,
  54                                   uint64_t npages)
  55 {
  56     uint8_t shift = rb->clear_bmap_shift;
  57
  58     bitmap_set_atomic(rb->clear_bmap, start >> shift,
  59                       clear_bmap_size(npages, shift));
  60 }
  61
  62 /**
  63  * clear_bmap_test_and_clear: test clear bitmap for the page, clear if set
  64  *
  65  * @rb: the ramblock to operate on
  66  * @page: the page number to check
  67  *
  68  * Returns: true if the bit was set, false otherwise
  69  */
  70 static inline bool clear_bmap_test_and_clear(RAMBlock *rb, uint64_t page)
  71 {
  72     uint8_t shift = rb->clear_bmap_shift;
  73
  74     return bitmap_test_and_clear_atomic(rb->clear_bmap, page >> shift, 1);
  75 }
  76
  77 static inline bool offset_in_ramblock(RAMBlock *b, ram_addr_t offset)
  78 {
  79     return (b && b->host && offset < b->used_length) ? true : false;
  80 }
  81
  82 static inline void *ramblock_ptr(RAMBlock *block, ram_addr_t offset)
  83 {
  84     assert(offset_in_ramblock(block, offset));
  85     return (char *)block->host + offset;
  86 }
  87
  88 static inline unsigned long int ramblock_recv_bitmap_offset(void *host_addr,
  89                                                             RAMBlock *rb)
  90 {
  91     uint64_t host_addr_offset =
  92             (uint64_t)(uintptr_t)(host_addr - (void *)rb->host);
  93     return host_addr_offset >> TARGET_PAGE_BITS;
  94 }
  95
  96 bool ramblock_is_pmem(RAMBlock *rb);
  97
  98 long qemu_minrampagesize(void);
  99 long qemu_maxrampagesize(void);
 100
 101 /**
 102  * qemu_ram_alloc_from_file,
 103  * qemu_ram_alloc_from_fd:  Allocate a ram block from the specified backing
 104  *                          file or device
 105  *
 106  * Parameters:
 107  *  @size: the size in bytes of the ram block
 108  *  @mr: the memory region where the ram block is
 109  *  @ram_flags: RamBlock flags. Supported flags: RAM_SHARED, RAM_PMEM,
 110  *              RAM_NORESERVE.
 111  *  @mem_path or @fd: specify the backing file or device
 112  *  @readonly: true to open @path for reading, false for read/write.
 113  *  @errp: pointer to Error*, to store an error if it happens
 114  *
 115  * Return:
 116  *  On success, return a pointer to the ram block.
 117  *  On failure, return NULL.
 118  */
 119 RAMBlock *qemu_ram_alloc_from_file(ram_addr_t size, MemoryRegion *mr,
 120                                    uint32_t ram_flags, const char *mem_path,
 121                                    bool readonly, Error **errp);
 122 RAMBlock *qemu_ram_alloc_from_fd(ram_addr_t size, MemoryRegion *mr,
 123                                  uint32_t ram_flags, int fd, off_t offset,
 124                                  bool readonly, Error **errp);
 125
 126 RAMBlock *qemu_ram_alloc_from_ptr(ram_addr_t size, void *host,
 127                                   MemoryRegion *mr, Error **errp);
 128 RAMBlock *qemu_ram_alloc(ram_addr_t size, uint32_t ram_flags, MemoryRegion *mr,
 129                          Error **errp);
 130 RAMBlock *qemu_ram_alloc_resizeable(ram_addr_t size, ram_addr_t max_size,
 131                                     void (*resized)(const char*,
 132                                                     uint64_t length,
 133                                                     void *host),
 134                                     MemoryRegion *mr, Error **errp);
 135 void qemu_ram_free(RAMBlock *block);
 136
 137 int qemu_ram_resize(RAMBlock *block, ram_addr_t newsize, Error **errp);
 138
 139 void qemu_ram_msync(RAMBlock *block, ram_addr_t start, ram_addr_t length);
 140
 141 /* Clear whole block of mem */
 142 static inline void qemu_ram_block_writeback(RAMBlock *block)
 143 {
 144     qemu_ram_msync(block, 0, block->used_length);
 145 }
 146
 147 #define DIRTY_CLIENTS_ALL     ((1 << DIRTY_MEMORY_NUM) - 1)
 148 #define DIRTY_CLIENTS_NOCODE  (DIRTY_CLIENTS_ALL & ~(1 << DIRTY_MEMORY_CODE))
 149
 150 static inline bool cpu_physical_memory_get_dirty(ram_addr_t start,
 151                                                  ram_addr_t length,
 152                                                  unsigned client)
 153 {
 154     DirtyMemoryBlocks *blocks;
 155     unsigned long end, page;
 156     unsigned long idx, offset, base;
 157     bool dirty = false;
 158
 159     assert(client < DIRTY_MEMORY_NUM);
 160
 161     end = TARGET_PAGE_ALIGN(start + length) >> TARGET_PAGE_BITS;
 162     page = start >> TARGET_PAGE_BITS;
 163
 164     WITH_RCU_READ_LOCK_GUARD() {
 165         blocks = qatomic_rcu_read(&ram_list.dirty_memory[client]);
 166
 167         idx = page / DIRTY_MEMORY_BLOCK_SIZE;
 168         offset = page % DIRTY_MEMORY_BLOCK_SIZE;
 169         base = page - offset;
 170         while (page < end) {
 171             unsigned long next = MIN(end, base + DIRTY_MEMORY_BLOCK_SIZE);
 172             unsigned long num = next - base;
 173             unsigned long found = find_next_bit(blocks->blocks[idx],
 174                                                 num, offset);
 175             if (found < num) {
 176                 dirty = true;
 177                 break;
 178             }
 179
 180             page = next;
 181             idx++;
 182             offset = 0;
 183             base += DIRTY_MEMORY_BLOCK_SIZE;
 184         }
 185     }
 186
 187     return dirty;
 188 }
 189
 190 static inline bool cpu_physical_memory_all_dirty(ram_addr_t start,
 191                                                  ram_addr_t length,
 192                                                  unsigned client)
 193 {
 194     DirtyMemoryBlocks *blocks;
 195     unsigned long end, page;
 196     unsigned long idx, offset, base;
 197     bool dirty = true;
 198
 199     assert(client < DIRTY_MEMORY_NUM);
 200
 201     end = TARGET_PAGE_ALIGN(start + length) >> TARGET_PAGE_BITS;
 202     page = start >> TARGET_PAGE_BITS;
 203
 204     RCU_READ_LOCK_GUARD();
 205
 206     blocks = qatomic_rcu_read(&ram_list.dirty_memory[client]);
 207
 208     idx = page / DIRTY_MEMORY_BLOCK_SIZE;
 209     offset = page % DIRTY_MEMORY_BLOCK_SIZE;
 210     base = page - offset;
 211     while (page < end) {
 212         unsigned long next = MIN(end, base + DIRTY_MEMORY_BLOCK_SIZE);
 213         unsigned long num = next - base;
 214         unsigned long found = find_next_zero_bit(blocks->blocks[idx], num, offset);
 215         if (found < num) {
 216             dirty = false;
 217             break;
 218         }
 219
 220         page = next;
 221         idx++;
 222         offset = 0;
 223         base += DIRTY_MEMORY_BLOCK_SIZE;
 224     }
 225
 226     return dirty;
 227 }
 228
 229 static inline bool cpu_physical_memory_get_dirty_flag(ram_addr_t addr,
 230                                                       unsigned client)
 231 {
 232     return cpu_physical_memory_get_dirty(addr, 1, client);
 233 }
 234
 235 static inline bool cpu_physical_memory_is_clean(ram_addr_t addr)
 236 {
 237     bool vga = cpu_physical_memory_get_dirty_flag(addr, DIRTY_MEMORY_VGA);
 238     bool code = cpu_physical_memory_get_dirty_flag(addr, DIRTY_MEMORY_CODE);
 239     bool migration =
 240         cpu_physical_memory_get_dirty_flag(addr, DIRTY_MEMORY_MIGRATION);
 241     return !(vga && code && migration);
 242 }
 243
 244 static inline uint8_t cpu_physical_memory_range_includes_clean(ram_addr_t start,
 245                                                                ram_addr_t length,
 246                                                                uint8_t mask)
 247 {
 248     uint8_t ret = 0;
 249
 250     if (mask & (1 << DIRTY_MEMORY_VGA) &&
 251         !cpu_physical_memory_all_dirty(start, length, DIRTY_MEMORY_VGA)) {
 252         ret |= (1 << DIRTY_MEMORY_VGA);
 253     }
 254     if (mask & (1 << DIRTY_MEMORY_CODE) &&
 255         !cpu_physical_memory_all_dirty(start, length, DIRTY_MEMORY_CODE)) {
 256         ret |= (1 << DIRTY_MEMORY_CODE);
 257     }
 258     if (mask & (1 << DIRTY_MEMORY_MIGRATION) &&
 259         !cpu_physical_memory_all_dirty(start, length, DIRTY_MEMORY_MIGRATION)) {
 260         ret |= (1 << DIRTY_MEMORY_MIGRATION);
 261     }
 262     return ret;
 263 }
 264
 265 static inline void cpu_physical_memory_set_dirty_flag(ram_addr_t addr,
 266                                                       unsigned client)
 267 {
 268     unsigned long page, idx, offset;
 269     DirtyMemoryBlocks *blocks;
 270
 271     assert(client < DIRTY_MEMORY_NUM);
 272
 273     page = addr >> TARGET_PAGE_BITS;
 274     idx = page / DIRTY_MEMORY_BLOCK_SIZE;
 275     offset = page % DIRTY_MEMORY_BLOCK_SIZE;
 276
 277     RCU_READ_LOCK_GUARD();
 278
 279     blocks = qatomic_rcu_read(&ram_list.dirty_memory[client]);
 280
 281     set_bit_atomic(offset, blocks->blocks[idx]);
 282 }
 283
 284 static inline void cpu_physical_memory_set_dirty_range(ram_addr_t start,
 285                                                        ram_addr_t length,
 286                                                        uint8_t mask)
 287 {
 288     DirtyMemoryBlocks *blocks[DIRTY_MEMORY_NUM];
 289     unsigned long end, page;
 290     unsigned long idx, offset, base;
 291     int i;
 292
 293     if (!mask && !xen_enabled()) {
 294         return;
 295     }
 296
 297     end = TARGET_PAGE_ALIGN(start + length) >> TARGET_PAGE_BITS;
 298     page = start >> TARGET_PAGE_BITS;
 299
 300     WITH_RCU_READ_LOCK_GUARD() {
 301         for (i = 0; i < DIRTY_MEMORY_NUM; i++) {
 302             blocks[i] = qatomic_rcu_read(&ram_list.dirty_memory[i]);
 303         }
 304
 305         idx = page / DIRTY_MEMORY_BLOCK_SIZE;
 306         offset = page % DIRTY_MEMORY_BLOCK_SIZE;
 307         base = page - offset;
 308         while (page < end) {
 309             unsigned long next = MIN(end, base + DIRTY_MEMORY_BLOCK_SIZE);
 310
 311             if (likely(mask & (1 << DIRTY_MEMORY_MIGRATION))) {
 312                 bitmap_set_atomic(blocks[DIRTY_MEMORY_MIGRATION]->blocks[idx],
 313                                   offset, next - page);
 314             }
 315             if (unlikely(mask & (1 << DIRTY_MEMORY_VGA))) {
 316                 bitmap_set_atomic(blocks[DIRTY_MEMORY_VGA]->blocks[idx],
 317                                   offset, next - page);
 318             }
 319             if (unlikely(mask & (1 << DIRTY_MEMORY_CODE))) {
 320                 bitmap_set_atomic(blocks[DIRTY_MEMORY_CODE]->blocks[idx],
 321                                   offset, next - page);
 322             }
 323
 324             page = next;
 325             idx++;
 326             offset = 0;
 327             base += DIRTY_MEMORY_BLOCK_SIZE;
 328         }
 329     }
 330
 331     xen_hvm_modified_memory(start, length);
 332 }
 333
 334 #if !defined(_WIN32)
 335 static inline void cpu_physical_memory_set_dirty_lebitmap(unsigned long *bitmap,
 336                                                           ram_addr_t start,
 337                                                           ram_addr_t pages)
 338 {
 339     unsigned long i, j;
 340     unsigned long page_number, c;
 341     hwaddr addr;
 342     ram_addr_t ram_addr;
 343     unsigned long len = (pages + HOST_LONG_BITS - 1) / HOST_LONG_BITS;
 344     unsigned long hpratio = qemu_real_host_page_size() / TARGET_PAGE_SIZE;
 345     unsigned long page = BIT_WORD(start >> TARGET_PAGE_BITS);
 346
 347     /* start address is aligned at the start of a word? */
 348     if ((((page * BITS_PER_LONG) << TARGET_PAGE_BITS) == start) &&
 349         (hpratio == 1)) {
 350         unsigned long **blocks[DIRTY_MEMORY_NUM];
 351         unsigned long idx;
 352         unsigned long offset;
 353         long k;
 354         long nr = BITS_TO_LONGS(pages);
 355
 356         idx = (start >> TARGET_PAGE_BITS) / DIRTY_MEMORY_BLOCK_SIZE;
 357         offset = BIT_WORD((start >> TARGET_PAGE_BITS) %
 358                           DIRTY_MEMORY_BLOCK_SIZE);
 359
 360         WITH_RCU_READ_LOCK_GUARD() {
 361             for (i = 0; i < DIRTY_MEMORY_NUM; i++) {
 362                 blocks[i] =
 363                     qatomic_rcu_read(&ram_list.dirty_memory[i])->blocks;
 364             }
 365
 366             for (k = 0; k < nr; k++) {
 367                 if (bitmap[k]) {
 368                     unsigned long temp = leul_to_cpu(bitmap[k]);
 369
 370                     qatomic_or(&blocks[DIRTY_MEMORY_VGA][idx][offset], temp);
 371
 372                     if (global_dirty_tracking) {
 373                         qatomic_or(
 374                                 &blocks[DIRTY_MEMORY_MIGRATION][idx][offset],
 375                                 temp);
 376                         if (unlikely(
 377                             global_dirty_tracking & GLOBAL_DIRTY_DIRTY_RATE)) {
 378                             total_dirty_pages += ctpopl(temp);
 379                         }
 380                     }
 381
 382                     if (tcg_enabled()) {
 383                         qatomic_or(&blocks[DIRTY_MEMORY_CODE][idx][offset],
 384                                    temp);
 385                     }
 386                 }
 387
 388                 if (++offset >= BITS_TO_LONGS(DIRTY_MEMORY_BLOCK_SIZE)) {
 389                     offset = 0;
 390                     idx++;
 391                 }
 392             }
 393         }
 394
 395         xen_hvm_modified_memory(start, pages << TARGET_PAGE_BITS);
 396     } else {
 397         uint8_t clients = tcg_enabled() ? DIRTY_CLIENTS_ALL : DIRTY_CLIENTS_NOCODE;
 398
 399         if (!global_dirty_tracking) {
 400             clients &= ~(1 << DIRTY_MEMORY_MIGRATION);
 401         }
 402
 403         /*
 404          * bitmap-traveling is faster than memory-traveling (for addr...)
 405          * especially when most of the memory is not dirty.
 406          */
 407         for (i = 0; i < len; i++) {
 408             if (bitmap[i] != 0) {
 409                 c = leul_to_cpu(bitmap[i]);
 410                 if (unlikely(global_dirty_tracking & GLOBAL_DIRTY_DIRTY_RATE)) {
 411                     total_dirty_pages += ctpopl(c);
 412                 }
 413                 do {
 414                     j = ctzl(c);
 415                     c &= ~(1ul << j);
 416                     page_number = (i * HOST_LONG_BITS + j) * hpratio;
 417                     addr = page_number * TARGET_PAGE_SIZE;
 418                     ram_addr = start + addr;
 419                     cpu_physical_memory_set_dirty_range(ram_addr,
 420                                        TARGET_PAGE_SIZE * hpratio, clients);
 421                 } while (c != 0);
 422             }
 423         }
 424     }
 425 }
 426 #endif /* not _WIN32 */
 427
 428 bool cpu_physical_memory_test_and_clear_dirty(ram_addr_t start,
 429                                               ram_addr_t length,
 430                                               unsigned client);
 431
 432 DirtyBitmapSnapshot *cpu_physical_memory_snapshot_and_clear_dirty
 433     (MemoryRegion *mr, hwaddr offset, hwaddr length, unsigned client);
 434
 435 bool cpu_physical_memory_snapshot_get_dirty(DirtyBitmapSnapshot *snap,
 436                                             ram_addr_t start,
 437                                             ram_addr_t length);
 438
 439 static inline void cpu_physical_memory_clear_dirty_range(ram_addr_t start,
 440                                                          ram_addr_t length)
 441 {
 442     cpu_physical_memory_test_and_clear_dirty(start, length, DIRTY_MEMORY_MIGRATION);
 443     cpu_physical_memory_test_and_clear_dirty(start, length, DIRTY_MEMORY_VGA);
 444     cpu_physical_memory_test_and_clear_dirty(start, length, DIRTY_MEMORY_CODE);
 445 }
 446
 447
 448 /* Called with RCU critical section */
 449 static inline
 450 uint64_t cpu_physical_memory_sync_dirty_bitmap(RAMBlock *rb,
 451                                                ram_addr_t start,
 452                                                ram_addr_t length)
 453 {
 454     ram_addr_t addr;
 455     unsigned long word = BIT_WORD((start + rb->offset) >> TARGET_PAGE_BITS);
 456     uint64_t num_dirty = 0;
 457     unsigned long *dest = rb->bmap;
 458
 459     /* start address and length is aligned at the start of a word? */
 460     if (((word * BITS_PER_LONG) << TARGET_PAGE_BITS) ==
 461          (start + rb->offset) &&
 462         !(length & ((BITS_PER_LONG << TARGET_PAGE_BITS) - 1))) {
 463         int k;
 464         int nr = BITS_TO_LONGS(length >> TARGET_PAGE_BITS);
 465         unsigned long * const *src;
 466         unsigned long idx = (word * BITS_PER_LONG) / DIRTY_MEMORY_BLOCK_SIZE;
 467         unsigned long offset = BIT_WORD((word * BITS_PER_LONG) %
 468                                         DIRTY_MEMORY_BLOCK_SIZE);
 469         unsigned long page = BIT_WORD(start >> TARGET_PAGE_BITS);
 470
 471         src = qatomic_rcu_read(
 472                 &ram_list.dirty_memory[DIRTY_MEMORY_MIGRATION])->blocks;
 473
 474         for (k = page; k < page + nr; k++) {
 475             if (src[idx][offset]) {
 476                 unsigned long bits = qatomic_xchg(&src[idx][offset], 0);
 477                 unsigned long new_dirty;
 478                 new_dirty = ~dest[k];
 479                 dest[k] |= bits;
 480                 new_dirty &= bits;
 481                 num_dirty += ctpopl(new_dirty);
 482             }
 483
 484             if (++offset >= BITS_TO_LONGS(DIRTY_MEMORY_BLOCK_SIZE)) {
 485                 offset = 0;
 486                 idx++;
 487             }
 488         }
 489
 490         if (rb->clear_bmap) {
 491             /*
 492              * Postpone the dirty bitmap clear to the point before we
 493              * really send the pages, also we will split the clear
 494              * dirty procedure into smaller chunks.
 495              */
 496             clear_bmap_set(rb, start >> TARGET_PAGE_BITS,
 497                            length >> TARGET_PAGE_BITS);
 498         } else {
 499             /* Slow path - still do that in a huge chunk */
 500             memory_region_clear_dirty_bitmap(rb->mr, start, length);
 501         }
 502     } else {
 503         ram_addr_t offset = rb->offset;
 504
 505         for (addr = 0; addr < length; addr += TARGET_PAGE_SIZE) {
 506             if (cpu_physical_memory_test_and_clear_dirty(
 507                         start + addr + offset,
 508                         TARGET_PAGE_SIZE,
 509                         DIRTY_MEMORY_MIGRATION)) {
 510                 long k = (start + addr) >> TARGET_PAGE_BITS;
 511                 if (!test_and_set_bit(k, dest)) {
 512                     num_dirty++;
 513                 }
 514             }
 515         }
 516     }
 517
 518     return num_dirty;
 519 }
 520 #endif
 521 #endif