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 "hw/xen/xen.h"
25#include "sysemu/tcg.h"
26#include "exec/ramlist.h"
27
28struct RAMBlock {
29 struct rcu_head rcu;
30 struct MemoryRegion *mr;
31 uint8_t *host;
32 uint8_t *colo_cache; /* For colo, VM's ram cache */
33 ram_addr_t offset;
34 ram_addr_t used_length;
35 ram_addr_t max_length;
36 void (*resized)(const char*, uint64_t length, void *host);
37 uint32_t flags;
38 /* Protected by iothread lock. */
39 char idstr[256];
40 /* RCU-enabled, writes protected by the ramlist lock */
41 QLIST_ENTRY(RAMBlock) next;
42 QLIST_HEAD(, RAMBlockNotifier) ramblock_notifiers;
43 int fd;
44 size_t page_size;
45 /* dirty bitmap used during migration */
46 unsigned long *bmap;
47 /* bitmap of pages that haven't been sent even once
48 * only maintained and used in postcopy at the moment
49 * where it's used to send the dirtymap at the start
50 * of the postcopy phase
51 */
52 unsigned long *unsentmap;
53 /* bitmap of already received pages in postcopy */
54 unsigned long *receivedmap;
55
56 /*
57 * bitmap to track already cleared dirty bitmap. When the bit is
58 * set, it means the corresponding memory chunk needs a log-clear.
59 * Set this up to non-NULL to enable the capability to postpone
60 * and split clearing of dirty bitmap on the remote node (e.g.,
61 * KVM). The bitmap will be set only when doing global sync.
62 *
63 * NOTE: this bitmap is different comparing to the other bitmaps
64 * in that one bit can represent multiple guest pages (which is
65 * decided by the `clear_bmap_shift' variable below). On
66 * destination side, this should always be NULL, and the variable
67 * `clear_bmap_shift' is meaningless.
68 */
69 unsigned long *clear_bmap;
70 uint8_t clear_bmap_shift;
71};
72
73/**
74 * clear_bmap_size: calculate clear bitmap size
75 *
76 * @pages: number of guest pages
77 * @shift: guest page number shift
78 *
79 * Returns: number of bits for the clear bitmap
80 */
81static inline long clear_bmap_size(uint64_t pages, uint8_t shift)
82{
83 return DIV_ROUND_UP(pages, 1UL << shift);
84}
85
86/**
87 * clear_bmap_set: set clear bitmap for the page range
88 *
89 * @rb: the ramblock to operate on
90 * @start: the start page number
91 * @size: number of pages to set in the bitmap
92 *
93 * Returns: None
94 */
95static inline void clear_bmap_set(RAMBlock *rb, uint64_t start,
96 uint64_t npages)
97{
98 uint8_t shift = rb->clear_bmap_shift;
99
100 bitmap_set_atomic(rb->clear_bmap, start >> shift,
101 clear_bmap_size(npages, shift));
102}
103
104/**
105 * clear_bmap_test_and_clear: test clear bitmap for the page, clear if set
106 *
107 * @rb: the ramblock to operate on
108 * @page: the page number to check
109 *
110 * Returns: true if the bit was set, false otherwise
111 */
112static inline bool clear_bmap_test_and_clear(RAMBlock *rb, uint64_t page)
113{
114 uint8_t shift = rb->clear_bmap_shift;
115
116 return bitmap_test_and_clear_atomic(rb->clear_bmap, page >> shift, 1);
117}
118
119static inline bool offset_in_ramblock(RAMBlock *b, ram_addr_t offset)
120{
121 return (b && b->host && offset < b->used_length) ? true : false;
122}
123
124static inline void *ramblock_ptr(RAMBlock *block, ram_addr_t offset)
125{
126 assert(offset_in_ramblock(block, offset));
127 return (char *)block->host + offset;
128}
129
130static inline unsigned long int ramblock_recv_bitmap_offset(void *host_addr,
131 RAMBlock *rb)
132{
133 uint64_t host_addr_offset =
134 (uint64_t)(uintptr_t)(host_addr - (void *)rb->host);
135 return host_addr_offset >> TARGET_PAGE_BITS;
136}
137
138bool ramblock_is_pmem(RAMBlock *rb);
139
140long qemu_minrampagesize(void);
141long qemu_maxrampagesize(void);
142
143/**
144 * qemu_ram_alloc_from_file,
145 * qemu_ram_alloc_from_fd: Allocate a ram block from the specified backing
146 * file or device
147 *
148 * Parameters:
149 * @size: the size in bytes of the ram block
150 * @mr: the memory region where the ram block is
151 * @ram_flags: specify the properties of the ram block, which can be one
152 * or bit-or of following values
153 * - RAM_SHARED: mmap the backing file or device with MAP_SHARED
154 * - RAM_PMEM: the backend @mem_path or @fd is persistent memory
155 * Other bits are ignored.
156 * @mem_path or @fd: specify the backing file or device
157 * @errp: pointer to Error*, to store an error if it happens
158 *
159 * Return:
160 * On success, return a pointer to the ram block.
161 * On failure, return NULL.
162 */
163RAMBlock *qemu_ram_alloc_from_file(ram_addr_t size, MemoryRegion *mr,
164 uint32_t ram_flags, const char *mem_path,
165 Error **errp);
166RAMBlock *qemu_ram_alloc_from_fd(ram_addr_t size, MemoryRegion *mr,
167 uint32_t ram_flags, int fd,
168 Error **errp);
169
170RAMBlock *qemu_ram_alloc_from_ptr(ram_addr_t size, void *host,
171 MemoryRegion *mr, Error **errp);
172RAMBlock *qemu_ram_alloc(ram_addr_t size, bool share, MemoryRegion *mr,
173 Error **errp);
174RAMBlock *qemu_ram_alloc_resizeable(ram_addr_t size, ram_addr_t max_size,
175 void (*resized)(const char*,
176 uint64_t length,
177 void *host),
178 MemoryRegion *mr, Error **errp);
179void qemu_ram_free(RAMBlock *block);
180
181int qemu_ram_resize(RAMBlock *block, ram_addr_t newsize, Error **errp);
182
183#define DIRTY_CLIENTS_ALL ((1 << DIRTY_MEMORY_NUM) - 1)
184#define DIRTY_CLIENTS_NOCODE (DIRTY_CLIENTS_ALL & ~(1 << DIRTY_MEMORY_CODE))
185
186void tb_invalidate_phys_range(ram_addr_t start, ram_addr_t end);
187
188static inline bool cpu_physical_memory_get_dirty(ram_addr_t start,
189 ram_addr_t length,
190 unsigned client)
191{
192 DirtyMemoryBlocks *blocks;
193 unsigned long end, page;
194 unsigned long idx, offset, base;
195 bool dirty = false;
196
197 assert(client < DIRTY_MEMORY_NUM);
198
199 end = TARGET_PAGE_ALIGN(start + length) >> TARGET_PAGE_BITS;
200 page = start >> TARGET_PAGE_BITS;
201
202 rcu_read_lock();
203
204 blocks = atomic_rcu_read(&ram_list.dirty_memory[client]);
205
206 idx = page / DIRTY_MEMORY_BLOCK_SIZE;
207 offset = page % DIRTY_MEMORY_BLOCK_SIZE;
208 base = page - offset;
209 while (page < end) {
210 unsigned long next = MIN(end, base + DIRTY_MEMORY_BLOCK_SIZE);
211 unsigned long num = next - base;
212 unsigned long found = find_next_bit(blocks->blocks[idx], num, offset);
213 if (found < num) {
214 dirty = true;
215 break;
216 }
217
218 page = next;
219 idx++;
220 offset = 0;
221 base += DIRTY_MEMORY_BLOCK_SIZE;
222 }
223
224 rcu_read_unlock();
225
226 return dirty;
227}
228
229static inline bool cpu_physical_memory_all_dirty(ram_addr_t start,
230 ram_addr_t length,
231 unsigned client)
232{
233 DirtyMemoryBlocks *blocks;
234 unsigned long end, page;
235 unsigned long idx, offset, base;
236 bool dirty = true;
237
238 assert(client < DIRTY_MEMORY_NUM);
239
240 end = TARGET_PAGE_ALIGN(start + length) >> TARGET_PAGE_BITS;
241 page = start >> TARGET_PAGE_BITS;
242
243 rcu_read_lock();
244
245 blocks = atomic_rcu_read(&ram_list.dirty_memory[client]);
246
247 idx = page / DIRTY_MEMORY_BLOCK_SIZE;
248 offset = page % DIRTY_MEMORY_BLOCK_SIZE;
249 base = page - offset;
250 while (page < end) {
251 unsigned long next = MIN(end, base + DIRTY_MEMORY_BLOCK_SIZE);
252 unsigned long num = next - base;
253 unsigned long found = find_next_zero_bit(blocks->blocks[idx], num, offset);
254 if (found < num) {
255 dirty = false;
256 break;
257 }
258
259 page = next;
260 idx++;
261 offset = 0;
262 base += DIRTY_MEMORY_BLOCK_SIZE;
263 }
264
265 rcu_read_unlock();
266
267 return dirty;
268}
269
270static inline bool cpu_physical_memory_get_dirty_flag(ram_addr_t addr,
271 unsigned client)
272{
273 return cpu_physical_memory_get_dirty(addr, 1, client);
274}
275
276static inline bool cpu_physical_memory_is_clean(ram_addr_t addr)
277{
278 bool vga = cpu_physical_memory_get_dirty_flag(addr, DIRTY_MEMORY_VGA);
279 bool code = cpu_physical_memory_get_dirty_flag(addr, DIRTY_MEMORY_CODE);
280 bool migration =
281 cpu_physical_memory_get_dirty_flag(addr, DIRTY_MEMORY_MIGRATION);
282 return !(vga && code && migration);
283}
284
285static inline uint8_t cpu_physical_memory_range_includes_clean(ram_addr_t start,
286 ram_addr_t length,
287 uint8_t mask)
288{
289 uint8_t ret = 0;
290
291 if (mask & (1 << DIRTY_MEMORY_VGA) &&
292 !cpu_physical_memory_all_dirty(start, length, DIRTY_MEMORY_VGA)) {
293 ret |= (1 << DIRTY_MEMORY_VGA);
294 }
295 if (mask & (1 << DIRTY_MEMORY_CODE) &&
296 !cpu_physical_memory_all_dirty(start, length, DIRTY_MEMORY_CODE)) {
297 ret |= (1 << DIRTY_MEMORY_CODE);
298 }
299 if (mask & (1 << DIRTY_MEMORY_MIGRATION) &&
300 !cpu_physical_memory_all_dirty(start, length, DIRTY_MEMORY_MIGRATION)) {
301 ret |= (1 << DIRTY_MEMORY_MIGRATION);
302 }
303 return ret;
304}
305
306static inline void cpu_physical_memory_set_dirty_flag(ram_addr_t addr,
307 unsigned client)
308{
309 unsigned long page, idx, offset;
310 DirtyMemoryBlocks *blocks;
311
312 assert(client < DIRTY_MEMORY_NUM);
313
314 page = addr >> TARGET_PAGE_BITS;
315 idx = page / DIRTY_MEMORY_BLOCK_SIZE;
316 offset = page % DIRTY_MEMORY_BLOCK_SIZE;
317
318 rcu_read_lock();
319
320 blocks = atomic_rcu_read(&ram_list.dirty_memory[client]);
321
322 set_bit_atomic(offset, blocks->blocks[idx]);
323
324 rcu_read_unlock();
325}
326
327static inline void cpu_physical_memory_set_dirty_range(ram_addr_t start,
328 ram_addr_t length,
329 uint8_t mask)
330{
331 DirtyMemoryBlocks *blocks[DIRTY_MEMORY_NUM];
332 unsigned long end, page;
333 unsigned long idx, offset, base;
334 int i;
335
336 if (!mask && !xen_enabled()) {
337 return;
338 }
339
340 end = TARGET_PAGE_ALIGN(start + length) >> TARGET_PAGE_BITS;
341 page = start >> TARGET_PAGE_BITS;
342
343 rcu_read_lock();
344
345 for (i = 0; i < DIRTY_MEMORY_NUM; i++) {
346 blocks[i] = atomic_rcu_read(&ram_list.dirty_memory[i]);
347 }
348
349 idx = page / DIRTY_MEMORY_BLOCK_SIZE;
350 offset = page % DIRTY_MEMORY_BLOCK_SIZE;
351 base = page - offset;
352 while (page < end) {
353 unsigned long next = MIN(end, base + DIRTY_MEMORY_BLOCK_SIZE);
354
355 if (likely(mask & (1 << DIRTY_MEMORY_MIGRATION))) {
356 bitmap_set_atomic(blocks[DIRTY_MEMORY_MIGRATION]->blocks[idx],
357 offset, next - page);
358 }
359 if (unlikely(mask & (1 << DIRTY_MEMORY_VGA))) {
360 bitmap_set_atomic(blocks[DIRTY_MEMORY_VGA]->blocks[idx],
361 offset, next - page);
362 }
363 if (unlikely(mask & (1 << DIRTY_MEMORY_CODE))) {
364 bitmap_set_atomic(blocks[DIRTY_MEMORY_CODE]->blocks[idx],
365 offset, next - page);
366 }
367
368 page = next;
369 idx++;
370 offset = 0;
371 base += DIRTY_MEMORY_BLOCK_SIZE;
372 }
373
374 rcu_read_unlock();
375
376 xen_hvm_modified_memory(start, length);
377}
378
379#if !defined(_WIN32)
380static inline void cpu_physical_memory_set_dirty_lebitmap(unsigned long *bitmap,
381 ram_addr_t start,
382 ram_addr_t pages)
383{
384 unsigned long i, j;
385 unsigned long page_number, c;
386 hwaddr addr;
387 ram_addr_t ram_addr;
388 unsigned long len = (pages + HOST_LONG_BITS - 1) / HOST_LONG_BITS;
389 unsigned long hpratio = getpagesize() / TARGET_PAGE_SIZE;
390 unsigned long page = BIT_WORD(start >> TARGET_PAGE_BITS);
391
392 /* start address is aligned at the start of a word? */
393 if ((((page * BITS_PER_LONG) << TARGET_PAGE_BITS) == start) &&
394 (hpratio == 1)) {
395 unsigned long **blocks[DIRTY_MEMORY_NUM];
396 unsigned long idx;
397 unsigned long offset;
398 long k;
399 long nr = BITS_TO_LONGS(pages);
400
401 idx = (start >> TARGET_PAGE_BITS) / DIRTY_MEMORY_BLOCK_SIZE;
402 offset = BIT_WORD((start >> TARGET_PAGE_BITS) %
403 DIRTY_MEMORY_BLOCK_SIZE);
404
405 rcu_read_lock();
406
407 for (i = 0; i < DIRTY_MEMORY_NUM; i++) {
408 blocks[i] = atomic_rcu_read(&ram_list.dirty_memory[i])->blocks;
409 }
410
411 for (k = 0; k < nr; k++) {
412 if (bitmap[k]) {
413 unsigned long temp = leul_to_cpu(bitmap[k]);
414
415 atomic_or(&blocks[DIRTY_MEMORY_VGA][idx][offset], temp);
416
417 if (global_dirty_log) {
418 atomic_or(&blocks[DIRTY_MEMORY_MIGRATION][idx][offset],
419 temp);
420 }
421
422 if (tcg_enabled()) {
423 atomic_or(&blocks[DIRTY_MEMORY_CODE][idx][offset], temp);
424 }
425 }
426
427 if (++offset >= BITS_TO_LONGS(DIRTY_MEMORY_BLOCK_SIZE)) {
428 offset = 0;
429 idx++;
430 }
431 }
432
433 rcu_read_unlock();
434
435 xen_hvm_modified_memory(start, pages << TARGET_PAGE_BITS);
436 } else {
437 uint8_t clients = tcg_enabled() ? DIRTY_CLIENTS_ALL : DIRTY_CLIENTS_NOCODE;
438
439 if (!global_dirty_log) {
440 clients &= ~(1 << DIRTY_MEMORY_MIGRATION);
441 }
442
443 /*
444 * bitmap-traveling is faster than memory-traveling (for addr...)
445 * especially when most of the memory is not dirty.
446 */
447 for (i = 0; i < len; i++) {
448 if (bitmap[i] != 0) {
449 c = leul_to_cpu(bitmap[i]);
450 do {
451 j = ctzl(c);
452 c &= ~(1ul << j);
453 page_number = (i * HOST_LONG_BITS + j) * hpratio;
454 addr = page_number * TARGET_PAGE_SIZE;
455 ram_addr = start + addr;
456 cpu_physical_memory_set_dirty_range(ram_addr,
457 TARGET_PAGE_SIZE * hpratio, clients);
458 } while (c != 0);
459 }
460 }
461 }
462}
463#endif /* not _WIN32 */
464
465bool cpu_physical_memory_test_and_clear_dirty(ram_addr_t start,
466 ram_addr_t length,
467 unsigned client);
468
469DirtyBitmapSnapshot *cpu_physical_memory_snapshot_and_clear_dirty
470 (MemoryRegion *mr, hwaddr offset, hwaddr length, unsigned client);
471
472bool cpu_physical_memory_snapshot_get_dirty(DirtyBitmapSnapshot *snap,
473 ram_addr_t start,
474 ram_addr_t length);
475
476static inline void cpu_physical_memory_clear_dirty_range(ram_addr_t start,
477 ram_addr_t length)
478{
479 cpu_physical_memory_test_and_clear_dirty(start, length, DIRTY_MEMORY_MIGRATION);
480 cpu_physical_memory_test_and_clear_dirty(start, length, DIRTY_MEMORY_VGA);
481 cpu_physical_memory_test_and_clear_dirty(start, length, DIRTY_MEMORY_CODE);
482}
483
484
485/* Called with RCU critical section */
486static inline
487uint64_t cpu_physical_memory_sync_dirty_bitmap(RAMBlock *rb,
488 ram_addr_t start,
489 ram_addr_t length,
490 uint64_t *real_dirty_pages)
491{
492 ram_addr_t addr;
493 unsigned long word = BIT_WORD((start + rb->offset) >> TARGET_PAGE_BITS);
494 uint64_t num_dirty = 0;
495 unsigned long *dest = rb->bmap;
496
497 /* start address and length is aligned at the start of a word? */
498 if (((word * BITS_PER_LONG) << TARGET_PAGE_BITS) ==
499 (start + rb->offset) &&
500 !(length & ((BITS_PER_LONG << TARGET_PAGE_BITS) - 1))) {
501 int k;
502 int nr = BITS_TO_LONGS(length >> TARGET_PAGE_BITS);
503 unsigned long * const *src;
504 unsigned long idx = (word * BITS_PER_LONG) / DIRTY_MEMORY_BLOCK_SIZE;
505 unsigned long offset = BIT_WORD((word * BITS_PER_LONG) %
506 DIRTY_MEMORY_BLOCK_SIZE);
507 unsigned long page = BIT_WORD(start >> TARGET_PAGE_BITS);
508
509 src = atomic_rcu_read(
510 &ram_list.dirty_memory[DIRTY_MEMORY_MIGRATION])->blocks;
511
512 for (k = page; k < page + nr; k++) {
513 if (src[idx][offset]) {
514 unsigned long bits = atomic_xchg(&src[idx][offset], 0);
515 unsigned long new_dirty;
516 *real_dirty_pages += ctpopl(bits);
517 new_dirty = ~dest[k];
518 dest[k] |= bits;
519 new_dirty &= bits;
520 num_dirty += ctpopl(new_dirty);
521 }
522
523 if (++offset >= BITS_TO_LONGS(DIRTY_MEMORY_BLOCK_SIZE)) {
524 offset = 0;
525 idx++;
526 }
527 }
528
529 if (rb->clear_bmap) {
530 /*
531 * Postpone the dirty bitmap clear to the point before we
532 * really send the pages, also we will split the clear
533 * dirty procedure into smaller chunks.
534 */
535 clear_bmap_set(rb, start >> TARGET_PAGE_BITS,
536 length >> TARGET_PAGE_BITS);
537 } else {
538 /* Slow path - still do that in a huge chunk */
539 memory_region_clear_dirty_bitmap(rb->mr, start, length);
540 }
541 } else {
542 ram_addr_t offset = rb->offset;
543
544 for (addr = 0; addr < length; addr += TARGET_PAGE_SIZE) {
545 if (cpu_physical_memory_test_and_clear_dirty(
546 start + addr + offset,
547 TARGET_PAGE_SIZE,
548 DIRTY_MEMORY_MIGRATION)) {
549 *real_dirty_pages += 1;
550 long k = (start + addr) >> TARGET_PAGE_BITS;
551 if (!test_and_set_bit(k, dest)) {
552 num_dirty++;
553 }
554 }
555 }
556 }
557
558 return num_dirty;
559}
560#endif
561#endif
562