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 SYSTEM_RAM_ADDR_H
20 #define SYSTEM_RAM_ADDR_H
21
22 #include "system/xen.h"
23 #include "system/tcg.h"
24 #include "exec/cputlb.h"
25 #include "exec/ramlist.h"
26 #include "system/ramblock.h"
27 #include "system/memory.h"
28 #include "exec/target_page.h"
29 #include "qemu/rcu.h"
30
31 #include "exec/hwaddr.h"
32 #include "exec/cpu-common.h"
33
34 extern uint64_t total_dirty_pages;
35
36 /**
37 * clear_bmap_size: calculate clear bitmap size
38 *
39 * @pages: number of guest pages
40 * @shift: guest page number shift
41 *
42 * Returns: number of bits for the clear bitmap
43 */
clear_bmap_size(uint64_t pages,uint8_t shift)44 static inline long clear_bmap_size(uint64_t pages, uint8_t shift)
45 {
46 return DIV_ROUND_UP(pages, 1UL << shift);
47 }
48
49 /**
50 * clear_bmap_set: set clear bitmap for the page range. Must be with
51 * bitmap_mutex held.
52 *
53 * @rb: the ramblock to operate on
54 * @start: the start page number
55 * @size: number of pages to set in the bitmap
56 *
57 * Returns: None
58 */
clear_bmap_set(RAMBlock * rb,uint64_t start,uint64_t npages)59 static inline void clear_bmap_set(RAMBlock *rb, uint64_t start,
60 uint64_t npages)
61 {
62 uint8_t shift = rb->clear_bmap_shift;
63
64 bitmap_set(rb->clear_bmap, start >> shift, clear_bmap_size(npages, shift));
65 }
66
67 /**
68 * clear_bmap_test_and_clear: test clear bitmap for the page, clear if set.
69 * Must be with bitmap_mutex held.
70 *
71 * @rb: the ramblock to operate on
72 * @page: the page number to check
73 *
74 * Returns: true if the bit was set, false otherwise
75 */
clear_bmap_test_and_clear(RAMBlock * rb,uint64_t page)76 static inline bool clear_bmap_test_and_clear(RAMBlock *rb, uint64_t page)
77 {
78 uint8_t shift = rb->clear_bmap_shift;
79
80 return bitmap_test_and_clear(rb->clear_bmap, page >> shift, 1);
81 }
82
offset_in_ramblock(RAMBlock * b,ram_addr_t offset)83 static inline bool offset_in_ramblock(RAMBlock *b, ram_addr_t offset)
84 {
85 return (b && b->host && offset < b->used_length) ? true : false;
86 }
87
ramblock_ptr(RAMBlock * block,ram_addr_t offset)88 static inline void *ramblock_ptr(RAMBlock *block, ram_addr_t offset)
89 {
90 assert(offset_in_ramblock(block, offset));
91 return (char *)block->host + offset;
92 }
93
ramblock_recv_bitmap_offset(void * host_addr,RAMBlock * rb)94 static inline unsigned long int ramblock_recv_bitmap_offset(void *host_addr,
95 RAMBlock *rb)
96 {
97 uint64_t host_addr_offset =
98 (uint64_t)(uintptr_t)(host_addr - (void *)rb->host);
99 return host_addr_offset >> TARGET_PAGE_BITS;
100 }
101
102 bool ramblock_is_pmem(RAMBlock *rb);
103
104 /**
105 * qemu_ram_alloc_from_file,
106 * qemu_ram_alloc_from_fd: Allocate a ram block from the specified backing
107 * file or device
108 *
109 * Parameters:
110 * @size: the size in bytes of the ram block
111 * @max_size: the maximum size of the block after resizing
112 * @mr: the memory region where the ram block is
113 * @resized: callback after calls to qemu_ram_resize
114 * @ram_flags: RamBlock flags. Supported flags: RAM_SHARED, RAM_PMEM,
115 * RAM_NORESERVE, RAM_PROTECTED, RAM_NAMED_FILE, RAM_READONLY,
116 * RAM_READONLY_FD, RAM_GUEST_MEMFD
117 * @mem_path or @fd: specify the backing file or device
118 * @offset: Offset into target file
119 * @grow: extend file if necessary (but an empty file is always extended).
120 * @errp: pointer to Error*, to store an error if it happens
121 *
122 * Return:
123 * On success, return a pointer to the ram block.
124 * On failure, return NULL.
125 */
126 typedef void (*qemu_ram_resize_cb)(const char *, uint64_t length, void *host);
127
128 RAMBlock *qemu_ram_alloc_from_file(ram_addr_t size, MemoryRegion *mr,
129 uint32_t ram_flags, const char *mem_path,
130 off_t offset, Error **errp);
131 RAMBlock *qemu_ram_alloc_from_fd(ram_addr_t size, ram_addr_t max_size,
132 qemu_ram_resize_cb resized, MemoryRegion *mr,
133 uint32_t ram_flags, int fd, off_t offset,
134 bool grow,
135 Error **errp);
136
137 RAMBlock *qemu_ram_alloc_from_ptr(ram_addr_t size, void *host,
138 MemoryRegion *mr, Error **errp);
139 RAMBlock *qemu_ram_alloc(ram_addr_t size, uint32_t ram_flags, MemoryRegion *mr,
140 Error **errp);
141 RAMBlock *qemu_ram_alloc_resizeable(ram_addr_t size, ram_addr_t max_size,
142 qemu_ram_resize_cb resized,
143 MemoryRegion *mr, Error **errp);
144 void qemu_ram_free(RAMBlock *block);
145
146 int qemu_ram_resize(RAMBlock *block, ram_addr_t newsize, Error **errp);
147
148 void qemu_ram_msync(RAMBlock *block, ram_addr_t start, ram_addr_t length);
149
150 /* Clear whole block of mem */
qemu_ram_block_writeback(RAMBlock * block)151 static inline void qemu_ram_block_writeback(RAMBlock *block)
152 {
153 qemu_ram_msync(block, 0, block->used_length);
154 }
155
156 #define DIRTY_CLIENTS_ALL ((1 << DIRTY_MEMORY_NUM) - 1)
157 #define DIRTY_CLIENTS_NOCODE (DIRTY_CLIENTS_ALL & ~(1 << DIRTY_MEMORY_CODE))
158
cpu_physical_memory_get_dirty(ram_addr_t start,ram_addr_t length,unsigned client)159 static inline bool cpu_physical_memory_get_dirty(ram_addr_t start,
160 ram_addr_t length,
161 unsigned client)
162 {
163 DirtyMemoryBlocks *blocks;
164 unsigned long end, page;
165 unsigned long idx, offset, base;
166 bool dirty = false;
167
168 assert(client < DIRTY_MEMORY_NUM);
169
170 end = TARGET_PAGE_ALIGN(start + length) >> TARGET_PAGE_BITS;
171 page = start >> TARGET_PAGE_BITS;
172
173 WITH_RCU_READ_LOCK_GUARD() {
174 blocks = qatomic_rcu_read(&ram_list.dirty_memory[client]);
175
176 idx = page / DIRTY_MEMORY_BLOCK_SIZE;
177 offset = page % DIRTY_MEMORY_BLOCK_SIZE;
178 base = page - offset;
179 while (page < end) {
180 unsigned long next = MIN(end, base + DIRTY_MEMORY_BLOCK_SIZE);
181 unsigned long num = next - base;
182 unsigned long found = find_next_bit(blocks->blocks[idx],
183 num, offset);
184 if (found < num) {
185 dirty = true;
186 break;
187 }
188
189 page = next;
190 idx++;
191 offset = 0;
192 base += DIRTY_MEMORY_BLOCK_SIZE;
193 }
194 }
195
196 return dirty;
197 }
198
cpu_physical_memory_all_dirty(ram_addr_t start,ram_addr_t length,unsigned client)199 static inline bool cpu_physical_memory_all_dirty(ram_addr_t start,
200 ram_addr_t length,
201 unsigned client)
202 {
203 DirtyMemoryBlocks *blocks;
204 unsigned long end, page;
205 unsigned long idx, offset, base;
206 bool dirty = true;
207
208 assert(client < DIRTY_MEMORY_NUM);
209
210 end = TARGET_PAGE_ALIGN(start + length) >> TARGET_PAGE_BITS;
211 page = start >> TARGET_PAGE_BITS;
212
213 RCU_READ_LOCK_GUARD();
214
215 blocks = qatomic_rcu_read(&ram_list.dirty_memory[client]);
216
217 idx = page / DIRTY_MEMORY_BLOCK_SIZE;
218 offset = page % DIRTY_MEMORY_BLOCK_SIZE;
219 base = page - offset;
220 while (page < end) {
221 unsigned long next = MIN(end, base + DIRTY_MEMORY_BLOCK_SIZE);
222 unsigned long num = next - base;
223 unsigned long found = find_next_zero_bit(blocks->blocks[idx], num, offset);
224 if (found < num) {
225 dirty = false;
226 break;
227 }
228
229 page = next;
230 idx++;
231 offset = 0;
232 base += DIRTY_MEMORY_BLOCK_SIZE;
233 }
234
235 return dirty;
236 }
237
cpu_physical_memory_get_dirty_flag(ram_addr_t addr,unsigned client)238 static inline bool cpu_physical_memory_get_dirty_flag(ram_addr_t addr,
239 unsigned client)
240 {
241 return cpu_physical_memory_get_dirty(addr, 1, client);
242 }
243
cpu_physical_memory_is_clean(ram_addr_t addr)244 static inline bool cpu_physical_memory_is_clean(ram_addr_t addr)
245 {
246 bool vga = cpu_physical_memory_get_dirty_flag(addr, DIRTY_MEMORY_VGA);
247 bool code = cpu_physical_memory_get_dirty_flag(addr, DIRTY_MEMORY_CODE);
248 bool migration =
249 cpu_physical_memory_get_dirty_flag(addr, DIRTY_MEMORY_MIGRATION);
250 return !(vga && code && migration);
251 }
252
cpu_physical_memory_range_includes_clean(ram_addr_t start,ram_addr_t length,uint8_t mask)253 static inline uint8_t cpu_physical_memory_range_includes_clean(ram_addr_t start,
254 ram_addr_t length,
255 uint8_t mask)
256 {
257 uint8_t ret = 0;
258
259 if (mask & (1 << DIRTY_MEMORY_VGA) &&
260 !cpu_physical_memory_all_dirty(start, length, DIRTY_MEMORY_VGA)) {
261 ret |= (1 << DIRTY_MEMORY_VGA);
262 }
263 if (mask & (1 << DIRTY_MEMORY_CODE) &&
264 !cpu_physical_memory_all_dirty(start, length, DIRTY_MEMORY_CODE)) {
265 ret |= (1 << DIRTY_MEMORY_CODE);
266 }
267 if (mask & (1 << DIRTY_MEMORY_MIGRATION) &&
268 !cpu_physical_memory_all_dirty(start, length, DIRTY_MEMORY_MIGRATION)) {
269 ret |= (1 << DIRTY_MEMORY_MIGRATION);
270 }
271 return ret;
272 }
273
cpu_physical_memory_set_dirty_flag(ram_addr_t addr,unsigned client)274 static inline void cpu_physical_memory_set_dirty_flag(ram_addr_t addr,
275 unsigned client)
276 {
277 unsigned long page, idx, offset;
278 DirtyMemoryBlocks *blocks;
279
280 assert(client < DIRTY_MEMORY_NUM);
281
282 page = addr >> TARGET_PAGE_BITS;
283 idx = page / DIRTY_MEMORY_BLOCK_SIZE;
284 offset = page % DIRTY_MEMORY_BLOCK_SIZE;
285
286 RCU_READ_LOCK_GUARD();
287
288 blocks = qatomic_rcu_read(&ram_list.dirty_memory[client]);
289
290 set_bit_atomic(offset, blocks->blocks[idx]);
291 }
292
cpu_physical_memory_set_dirty_range(ram_addr_t start,ram_addr_t length,uint8_t mask)293 static inline void cpu_physical_memory_set_dirty_range(ram_addr_t start,
294 ram_addr_t length,
295 uint8_t mask)
296 {
297 DirtyMemoryBlocks *blocks[DIRTY_MEMORY_NUM];
298 unsigned long end, page;
299 unsigned long idx, offset, base;
300 int i;
301
302 if (!mask && !xen_enabled()) {
303 return;
304 }
305
306 end = TARGET_PAGE_ALIGN(start + length) >> TARGET_PAGE_BITS;
307 page = start >> TARGET_PAGE_BITS;
308
309 WITH_RCU_READ_LOCK_GUARD() {
310 for (i = 0; i < DIRTY_MEMORY_NUM; i++) {
311 blocks[i] = qatomic_rcu_read(&ram_list.dirty_memory[i]);
312 }
313
314 idx = page / DIRTY_MEMORY_BLOCK_SIZE;
315 offset = page % DIRTY_MEMORY_BLOCK_SIZE;
316 base = page - offset;
317 while (page < end) {
318 unsigned long next = MIN(end, base + DIRTY_MEMORY_BLOCK_SIZE);
319
320 if (likely(mask & (1 << DIRTY_MEMORY_MIGRATION))) {
321 bitmap_set_atomic(blocks[DIRTY_MEMORY_MIGRATION]->blocks[idx],
322 offset, next - page);
323 }
324 if (unlikely(mask & (1 << DIRTY_MEMORY_VGA))) {
325 bitmap_set_atomic(blocks[DIRTY_MEMORY_VGA]->blocks[idx],
326 offset, next - page);
327 }
328 if (unlikely(mask & (1 << DIRTY_MEMORY_CODE))) {
329 bitmap_set_atomic(blocks[DIRTY_MEMORY_CODE]->blocks[idx],
330 offset, next - page);
331 }
332
333 page = next;
334 idx++;
335 offset = 0;
336 base += DIRTY_MEMORY_BLOCK_SIZE;
337 }
338 }
339
340 if (xen_enabled()) {
341 xen_hvm_modified_memory(start, length);
342 }
343 }
344
345 #if !defined(_WIN32)
346
347 /*
348 * Contrary to cpu_physical_memory_sync_dirty_bitmap() this function returns
349 * the number of dirty pages in @bitmap passed as argument. On the other hand,
350 * cpu_physical_memory_sync_dirty_bitmap() returns newly dirtied pages that
351 * weren't set in the global migration bitmap.
352 */
353 static inline
cpu_physical_memory_set_dirty_lebitmap(unsigned long * bitmap,ram_addr_t start,ram_addr_t pages)354 uint64_t cpu_physical_memory_set_dirty_lebitmap(unsigned long *bitmap,
355 ram_addr_t start,
356 ram_addr_t pages)
357 {
358 unsigned long i, j;
359 unsigned long page_number, c, nbits;
360 hwaddr addr;
361 ram_addr_t ram_addr;
362 uint64_t num_dirty = 0;
363 unsigned long len = (pages + HOST_LONG_BITS - 1) / HOST_LONG_BITS;
364 unsigned long hpratio = qemu_real_host_page_size() / TARGET_PAGE_SIZE;
365 unsigned long page = BIT_WORD(start >> TARGET_PAGE_BITS);
366
367 /* start address is aligned at the start of a word? */
368 if ((((page * BITS_PER_LONG) << TARGET_PAGE_BITS) == start) &&
369 (hpratio == 1)) {
370 unsigned long **blocks[DIRTY_MEMORY_NUM];
371 unsigned long idx;
372 unsigned long offset;
373 long k;
374 long nr = BITS_TO_LONGS(pages);
375
376 idx = (start >> TARGET_PAGE_BITS) / DIRTY_MEMORY_BLOCK_SIZE;
377 offset = BIT_WORD((start >> TARGET_PAGE_BITS) %
378 DIRTY_MEMORY_BLOCK_SIZE);
379
380 WITH_RCU_READ_LOCK_GUARD() {
381 for (i = 0; i < DIRTY_MEMORY_NUM; i++) {
382 blocks[i] =
383 qatomic_rcu_read(&ram_list.dirty_memory[i])->blocks;
384 }
385
386 for (k = 0; k < nr; k++) {
387 if (bitmap[k]) {
388 unsigned long temp = leul_to_cpu(bitmap[k]);
389
390 nbits = ctpopl(temp);
391 qatomic_or(&blocks[DIRTY_MEMORY_VGA][idx][offset], temp);
392
393 if (global_dirty_tracking) {
394 qatomic_or(
395 &blocks[DIRTY_MEMORY_MIGRATION][idx][offset],
396 temp);
397 if (unlikely(
398 global_dirty_tracking & GLOBAL_DIRTY_DIRTY_RATE)) {
399 total_dirty_pages += nbits;
400 }
401 }
402
403 num_dirty += nbits;
404
405 if (tcg_enabled()) {
406 qatomic_or(&blocks[DIRTY_MEMORY_CODE][idx][offset],
407 temp);
408 }
409 }
410
411 if (++offset >= BITS_TO_LONGS(DIRTY_MEMORY_BLOCK_SIZE)) {
412 offset = 0;
413 idx++;
414 }
415 }
416 }
417
418 if (xen_enabled()) {
419 xen_hvm_modified_memory(start, pages << TARGET_PAGE_BITS);
420 }
421 } else {
422 uint8_t clients = tcg_enabled() ? DIRTY_CLIENTS_ALL : DIRTY_CLIENTS_NOCODE;
423
424 if (!global_dirty_tracking) {
425 clients &= ~(1 << DIRTY_MEMORY_MIGRATION);
426 }
427
428 /*
429 * bitmap-traveling is faster than memory-traveling (for addr...)
430 * especially when most of the memory is not dirty.
431 */
432 for (i = 0; i < len; i++) {
433 if (bitmap[i] != 0) {
434 c = leul_to_cpu(bitmap[i]);
435 nbits = ctpopl(c);
436 if (unlikely(global_dirty_tracking & GLOBAL_DIRTY_DIRTY_RATE)) {
437 total_dirty_pages += nbits;
438 }
439 num_dirty += nbits;
440 do {
441 j = ctzl(c);
442 c &= ~(1ul << j);
443 page_number = (i * HOST_LONG_BITS + j) * hpratio;
444 addr = page_number * TARGET_PAGE_SIZE;
445 ram_addr = start + addr;
446 cpu_physical_memory_set_dirty_range(ram_addr,
447 TARGET_PAGE_SIZE * hpratio, clients);
448 } while (c != 0);
449 }
450 }
451 }
452
453 return num_dirty;
454 }
455 #endif /* not _WIN32 */
456
cpu_physical_memory_dirty_bits_cleared(ram_addr_t start,ram_addr_t length)457 static inline void cpu_physical_memory_dirty_bits_cleared(ram_addr_t start,
458 ram_addr_t length)
459 {
460 if (tcg_enabled()) {
461 tlb_reset_dirty_range_all(start, length);
462 }
463
464 }
465 bool cpu_physical_memory_test_and_clear_dirty(ram_addr_t start,
466 ram_addr_t length,
467 unsigned client);
468
469 DirtyBitmapSnapshot *cpu_physical_memory_snapshot_and_clear_dirty
470 (MemoryRegion *mr, hwaddr offset, hwaddr length, unsigned client);
471
472 bool cpu_physical_memory_snapshot_get_dirty(DirtyBitmapSnapshot *snap,
473 ram_addr_t start,
474 ram_addr_t length);
475
cpu_physical_memory_clear_dirty_range(ram_addr_t start,ram_addr_t length)476 static 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 */
486 static inline
cpu_physical_memory_sync_dirty_bitmap(RAMBlock * rb,ram_addr_t start,ram_addr_t length)487 uint64_t cpu_physical_memory_sync_dirty_bitmap(RAMBlock *rb,
488 ram_addr_t start,
489 ram_addr_t length)
490 {
491 ram_addr_t addr;
492 unsigned long word = BIT_WORD((start + rb->offset) >> TARGET_PAGE_BITS);
493 uint64_t num_dirty = 0;
494 unsigned long *dest = rb->bmap;
495
496 /* start address and length is aligned at the start of a word? */
497 if (((word * BITS_PER_LONG) << TARGET_PAGE_BITS) ==
498 (start + rb->offset) &&
499 !(length & ((BITS_PER_LONG << TARGET_PAGE_BITS) - 1))) {
500 int k;
501 int nr = BITS_TO_LONGS(length >> TARGET_PAGE_BITS);
502 unsigned long * const *src;
503 unsigned long idx = (word * BITS_PER_LONG) / DIRTY_MEMORY_BLOCK_SIZE;
504 unsigned long offset = BIT_WORD((word * BITS_PER_LONG) %
505 DIRTY_MEMORY_BLOCK_SIZE);
506 unsigned long page = BIT_WORD(start >> TARGET_PAGE_BITS);
507
508 src = qatomic_rcu_read(
509 &ram_list.dirty_memory[DIRTY_MEMORY_MIGRATION])->blocks;
510
511 for (k = page; k < page + nr; k++) {
512 if (src[idx][offset]) {
513 unsigned long bits = qatomic_xchg(&src[idx][offset], 0);
514 unsigned long new_dirty;
515 new_dirty = ~dest[k];
516 dest[k] |= bits;
517 new_dirty &= bits;
518 num_dirty += ctpopl(new_dirty);
519 }
520
521 if (++offset >= BITS_TO_LONGS(DIRTY_MEMORY_BLOCK_SIZE)) {
522 offset = 0;
523 idx++;
524 }
525 }
526 if (num_dirty) {
527 cpu_physical_memory_dirty_bits_cleared(start, length);
528 }
529
530 if (rb->clear_bmap) {
531 /*
532 * Postpone the dirty bitmap clear to the point before we
533 * really send the pages, also we will split the clear
534 * dirty procedure into smaller chunks.
535 */
536 clear_bmap_set(rb, start >> TARGET_PAGE_BITS,
537 length >> TARGET_PAGE_BITS);
538 } else {
539 /* Slow path - still do that in a huge chunk */
540 memory_region_clear_dirty_bitmap(rb->mr, start, length);
541 }
542 } else {
543 ram_addr_t offset = rb->offset;
544
545 for (addr = 0; addr < length; addr += TARGET_PAGE_SIZE) {
546 if (cpu_physical_memory_test_and_clear_dirty(
547 start + addr + offset,
548 TARGET_PAGE_SIZE,
549 DIRTY_MEMORY_MIGRATION)) {
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
561 #endif
562