]>
Commit | Line | Data |
---|---|---|
c163b5ca | 1 | /* |
2 | * QEMU live block migration | |
3 | * | |
4 | * Copyright IBM, Corp. 2009 | |
5 | * | |
6 | * Authors: | |
7 | * Liran Schour <lirans@il.ibm.com> | |
8 | * | |
9 | * This work is licensed under the terms of the GNU GPL, version 2. See | |
10 | * the COPYING file in the top-level directory. | |
11 | * | |
12 | */ | |
13 | ||
14 | #include "qemu-common.h" | |
15 | #include "block_int.h" | |
16 | #include "hw/hw.h" | |
5e5328be | 17 | #include "qemu-queue.h" |
c163b5ca | 18 | #include "block-migration.h" |
19 | #include <assert.h> | |
c163b5ca | 20 | |
6ea44308 | 21 | #define BLOCK_SIZE (BDRV_SECTORS_PER_DIRTY_CHUNK << BDRV_SECTOR_BITS) |
c163b5ca | 22 | |
23 | #define BLK_MIG_FLAG_DEVICE_BLOCK 0x01 | |
24 | #define BLK_MIG_FLAG_EOS 0x02 | |
25 | ||
26 | #define MAX_IS_ALLOCATED_SEARCH 65536 | |
27 | #define MAX_BLOCKS_READ 10000 | |
28 | #define BLOCKS_READ_CHANGE 100 | |
29 | #define INITIAL_BLOCKS_READ 100 | |
30 | ||
31 | //#define DEBUG_BLK_MIGRATION | |
32 | ||
33 | #ifdef DEBUG_BLK_MIGRATION | |
a55eb92c | 34 | #define dprintf(fmt, ...) \ |
c163b5ca | 35 | do { printf("blk_migration: " fmt, ## __VA_ARGS__); } while (0) |
36 | #else | |
a55eb92c | 37 | #define dprintf(fmt, ...) \ |
c163b5ca | 38 | do { } while (0) |
39 | #endif | |
40 | ||
a55eb92c JK |
41 | typedef struct BlkMigDevState { |
42 | BlockDriverState *bs; | |
43 | int bulk_completed; | |
44 | int shared_base; | |
a55eb92c JK |
45 | int64_t cur_sector; |
46 | int64_t total_sectors; | |
47 | int64_t dirty; | |
5e5328be | 48 | QSIMPLEQ_ENTRY(BlkMigDevState) entry; |
a55eb92c JK |
49 | } BlkMigDevState; |
50 | ||
c163b5ca | 51 | typedef struct BlkMigBlock { |
52 | uint8_t *buf; | |
53 | BlkMigDevState *bmds; | |
54 | int64_t sector; | |
55 | struct iovec iov; | |
56 | QEMUIOVector qiov; | |
57 | BlockDriverAIOCB *aiocb; | |
58 | int ret; | |
5e5328be | 59 | QSIMPLEQ_ENTRY(BlkMigBlock) entry; |
c163b5ca | 60 | } BlkMigBlock; |
61 | ||
62 | typedef struct BlkMigState { | |
c163b5ca | 63 | int blk_enable; |
64 | int shared_base; | |
5e5328be JK |
65 | QSIMPLEQ_HEAD(bmds_list, BlkMigDevState) bmds_list; |
66 | QSIMPLEQ_HEAD(blk_list, BlkMigBlock) blk_list; | |
c163b5ca | 67 | int submitted; |
68 | int read_done; | |
69 | int transferred; | |
70 | int64_t print_completion; | |
71 | } BlkMigState; | |
72 | ||
d11ecd3d | 73 | static BlkMigState block_mig_state; |
c163b5ca | 74 | |
13f0b67f JK |
75 | static void blk_send(QEMUFile *f, BlkMigBlock * blk) |
76 | { | |
77 | int len; | |
78 | ||
79 | /* sector number and flags */ | |
80 | qemu_put_be64(f, (blk->sector << BDRV_SECTOR_BITS) | |
81 | | BLK_MIG_FLAG_DEVICE_BLOCK); | |
82 | ||
83 | /* device name */ | |
84 | len = strlen(blk->bmds->bs->device_name); | |
85 | qemu_put_byte(f, len); | |
86 | qemu_put_buffer(f, (uint8_t *)blk->bmds->bs->device_name, len); | |
87 | ||
88 | qemu_put_buffer(f, blk->buf, BLOCK_SIZE); | |
89 | } | |
90 | ||
c163b5ca | 91 | static void blk_mig_read_cb(void *opaque, int ret) |
92 | { | |
93 | BlkMigBlock *blk = opaque; | |
a55eb92c | 94 | |
c163b5ca | 95 | blk->ret = ret; |
a55eb92c | 96 | |
5e5328be | 97 | QSIMPLEQ_INSERT_TAIL(&block_mig_state.blk_list, blk, entry); |
a55eb92c | 98 | |
d11ecd3d JK |
99 | block_mig_state.submitted--; |
100 | block_mig_state.read_done++; | |
101 | assert(block_mig_state.submitted >= 0); | |
c163b5ca | 102 | } |
103 | ||
57cce12d | 104 | static int mig_save_device_bulk(QEMUFile *f, BlkMigDevState *bmds, int is_async) |
a55eb92c | 105 | { |
57cce12d JK |
106 | int64_t total_sectors = bmds->total_sectors; |
107 | int64_t cur_sector = bmds->cur_sector; | |
108 | BlockDriverState *bs = bmds->bs; | |
c163b5ca | 109 | BlkMigBlock *blk; |
13f0b67f | 110 | int nr_sectors; |
a55eb92c | 111 | |
57cce12d | 112 | if (bmds->shared_base) { |
b1d10856 | 113 | while (cur_sector < total_sectors && |
57cce12d JK |
114 | !bdrv_is_allocated(bs, cur_sector, MAX_IS_ALLOCATED_SEARCH, |
115 | &nr_sectors)) { | |
c163b5ca | 116 | cur_sector += nr_sectors; |
117 | } | |
118 | } | |
a55eb92c JK |
119 | |
120 | if (cur_sector >= total_sectors) { | |
57cce12d | 121 | bmds->cur_sector = total_sectors; |
c163b5ca | 122 | return 1; |
123 | } | |
a55eb92c | 124 | |
d11ecd3d | 125 | if (cur_sector >= block_mig_state.print_completion) { |
c163b5ca | 126 | printf("Completed %" PRId64 " %%\r", cur_sector * 100 / total_sectors); |
127 | fflush(stdout); | |
d11ecd3d | 128 | block_mig_state.print_completion += |
6ea44308 | 129 | (BDRV_SECTORS_PER_DIRTY_CHUNK * 10000); |
c163b5ca | 130 | } |
a55eb92c | 131 | |
57cce12d JK |
132 | cur_sector &= ~((int64_t)BDRV_SECTORS_PER_DIRTY_CHUNK - 1); |
133 | ||
6ea44308 JK |
134 | /* we are going to transfer a full block even if it is not allocated */ |
135 | nr_sectors = BDRV_SECTORS_PER_DIRTY_CHUNK; | |
c163b5ca | 136 | |
6ea44308 | 137 | if (total_sectors - cur_sector < BDRV_SECTORS_PER_DIRTY_CHUNK) { |
57cce12d | 138 | nr_sectors = total_sectors - cur_sector; |
c163b5ca | 139 | } |
a55eb92c | 140 | |
13f0b67f JK |
141 | blk = qemu_malloc(sizeof(BlkMigBlock)); |
142 | blk->buf = qemu_malloc(BLOCK_SIZE); | |
143 | blk->bmds = bmds; | |
144 | blk->sector = cur_sector; | |
a55eb92c | 145 | |
13f0b67f | 146 | if (is_async) { |
57cce12d JK |
147 | blk->iov.iov_base = blk->buf; |
148 | blk->iov.iov_len = nr_sectors * BDRV_SECTOR_SIZE; | |
149 | qemu_iovec_init_external(&blk->qiov, &blk->iov, 1); | |
a55eb92c | 150 | |
57cce12d JK |
151 | blk->aiocb = bdrv_aio_readv(bs, cur_sector, &blk->qiov, |
152 | nr_sectors, blk_mig_read_cb, blk); | |
57cce12d JK |
153 | if (!blk->aiocb) { |
154 | printf("Error reading sector %" PRId64 "\n", cur_sector); | |
155 | qemu_free(blk->buf); | |
156 | qemu_free(blk); | |
157 | return 0; | |
158 | } | |
57cce12d | 159 | block_mig_state.submitted++; |
57cce12d | 160 | } else { |
13f0b67f | 161 | if (bdrv_read(bs, cur_sector, blk->buf, nr_sectors) < 0) { |
57cce12d | 162 | printf("Error reading sector %" PRId64 "\n", cur_sector); |
13f0b67f | 163 | return 0; |
c163b5ca | 164 | } |
13f0b67f | 165 | blk_send(f, blk); |
a55eb92c | 166 | |
13f0b67f JK |
167 | qemu_free(blk->buf); |
168 | qemu_free(blk); | |
c163b5ca | 169 | } |
170 | ||
13f0b67f JK |
171 | bdrv_reset_dirty(bs, cur_sector, nr_sectors); |
172 | bmds->cur_sector = cur_sector + nr_sectors; | |
a55eb92c | 173 | |
13f0b67f | 174 | return (bmds->cur_sector >= total_sectors); |
c163b5ca | 175 | } |
176 | ||
c163b5ca | 177 | static void set_dirty_tracking(int enable) |
178 | { | |
179 | BlkMigDevState *bmds; | |
5e5328be JK |
180 | |
181 | QSIMPLEQ_FOREACH(bmds, &block_mig_state.bmds_list, entry) { | |
a55eb92c | 182 | bdrv_set_dirty_tracking(bmds->bs, enable); |
c163b5ca | 183 | } |
c163b5ca | 184 | } |
185 | ||
186 | static void init_blk_migration(QEMUFile *f) | |
187 | { | |
5e5328be | 188 | BlkMigDevState *bmds; |
c163b5ca | 189 | BlockDriverState *bs; |
a55eb92c | 190 | |
69d63a97 JK |
191 | block_mig_state.submitted = 0; |
192 | block_mig_state.read_done = 0; | |
193 | block_mig_state.transferred = 0; | |
194 | block_mig_state.print_completion = 0; | |
195 | ||
c163b5ca | 196 | for (bs = bdrv_first; bs != NULL; bs = bs->next) { |
a55eb92c | 197 | if (bs->type == BDRV_TYPE_HD) { |
c163b5ca | 198 | bmds = qemu_mallocz(sizeof(BlkMigDevState)); |
199 | bmds->bs = bs; | |
200 | bmds->bulk_completed = 0; | |
6ea44308 | 201 | bmds->total_sectors = bdrv_getlength(bs) >> BDRV_SECTOR_BITS; |
d11ecd3d | 202 | bmds->shared_base = block_mig_state.shared_base; |
a55eb92c JK |
203 | |
204 | if (bmds->shared_base) { | |
205 | printf("Start migration for %s with shared base image\n", | |
c163b5ca | 206 | bs->device_name); |
207 | } else { | |
208 | printf("Start full migration for %s\n", bs->device_name); | |
209 | } | |
a55eb92c | 210 | |
5e5328be | 211 | QSIMPLEQ_INSERT_TAIL(&block_mig_state.bmds_list, bmds, entry); |
c163b5ca | 212 | } |
a55eb92c | 213 | } |
c163b5ca | 214 | } |
215 | ||
216 | static int blk_mig_save_bulked_block(QEMUFile *f, int is_async) | |
217 | { | |
218 | BlkMigDevState *bmds; | |
219 | ||
5e5328be | 220 | QSIMPLEQ_FOREACH(bmds, &block_mig_state.bmds_list, entry) { |
a55eb92c | 221 | if (bmds->bulk_completed == 0) { |
57cce12d JK |
222 | if (mig_save_device_bulk(f, bmds, is_async) == 1) { |
223 | /* completed bulk section for this device */ | |
224 | bmds->bulk_completed = 1; | |
c163b5ca | 225 | } |
226 | return 1; | |
227 | } | |
228 | } | |
a55eb92c | 229 | |
c163b5ca | 230 | /* we reached here means bulk is completed */ |
c163b5ca | 231 | return 0; |
c163b5ca | 232 | } |
233 | ||
234 | #define MAX_NUM_BLOCKS 4 | |
235 | ||
236 | static void blk_mig_save_dirty_blocks(QEMUFile *f) | |
237 | { | |
238 | BlkMigDevState *bmds; | |
13f0b67f | 239 | BlkMigBlock blk; |
c163b5ca | 240 | int64_t sector; |
a55eb92c | 241 | |
13f0b67f | 242 | blk.buf = qemu_malloc(BLOCK_SIZE); |
575a58d7 | 243 | |
5e5328be | 244 | QSIMPLEQ_FOREACH(bmds, &block_mig_state.bmds_list, entry) { |
a55eb92c JK |
245 | for (sector = 0; sector < bmds->cur_sector;) { |
246 | if (bdrv_get_dirty(bmds->bs, sector)) { | |
13f0b67f | 247 | if (bdrv_read(bmds->bs, sector, blk.buf, |
6ea44308 | 248 | BDRV_SECTORS_PER_DIRTY_CHUNK) < 0) { |
13f0b67f | 249 | printf("Error reading sector %" PRId64 "\n", sector); |
a55eb92c | 250 | /* FIXME: add error handling */ |
c163b5ca | 251 | } |
13f0b67f JK |
252 | blk.bmds = bmds; |
253 | blk.sector = sector; | |
254 | blk_send(f, &blk); | |
a55eb92c JK |
255 | |
256 | bdrv_reset_dirty(bmds->bs, sector, | |
6ea44308 | 257 | BDRV_SECTORS_PER_DIRTY_CHUNK); |
a55eb92c | 258 | } |
6ea44308 | 259 | sector += BDRV_SECTORS_PER_DIRTY_CHUNK; |
c163b5ca | 260 | } |
261 | } | |
575a58d7 | 262 | |
13f0b67f | 263 | qemu_free(blk.buf); |
c163b5ca | 264 | } |
265 | ||
266 | static void flush_blks(QEMUFile* f) | |
267 | { | |
5e5328be | 268 | BlkMigBlock *blk; |
a55eb92c | 269 | |
d11ecd3d JK |
270 | dprintf("%s Enter submitted %d read_done %d transferred %d\n", |
271 | __FUNCTION__, block_mig_state.submitted, block_mig_state.read_done, | |
272 | block_mig_state.transferred); | |
a55eb92c | 273 | |
5e5328be JK |
274 | while ((blk = QSIMPLEQ_FIRST(&block_mig_state.blk_list)) != NULL) { |
275 | if (qemu_file_rate_limit(f)) { | |
276 | break; | |
277 | } | |
13f0b67f | 278 | blk_send(f, blk); |
a55eb92c | 279 | |
5e5328be | 280 | QSIMPLEQ_REMOVE_HEAD(&block_mig_state.blk_list, entry); |
c163b5ca | 281 | qemu_free(blk->buf); |
282 | qemu_free(blk); | |
a55eb92c | 283 | |
d11ecd3d JK |
284 | block_mig_state.read_done--; |
285 | block_mig_state.transferred++; | |
286 | assert(block_mig_state.read_done >= 0); | |
c163b5ca | 287 | } |
c163b5ca | 288 | |
d11ecd3d JK |
289 | dprintf("%s Exit submitted %d read_done %d transferred %d\n", __FUNCTION__, |
290 | block_mig_state.submitted, block_mig_state.read_done, | |
291 | block_mig_state.transferred); | |
c163b5ca | 292 | } |
293 | ||
294 | static int is_stage2_completed(void) | |
295 | { | |
296 | BlkMigDevState *bmds; | |
a55eb92c | 297 | |
d11ecd3d | 298 | if (block_mig_state.submitted > 0) { |
c163b5ca | 299 | return 0; |
300 | } | |
a55eb92c | 301 | |
5e5328be | 302 | QSIMPLEQ_FOREACH(bmds, &block_mig_state.bmds_list, entry) { |
a55eb92c | 303 | if (bmds->bulk_completed == 0) { |
c163b5ca | 304 | return 0; |
305 | } | |
306 | } | |
a55eb92c | 307 | |
c163b5ca | 308 | return 1; |
309 | } | |
310 | ||
311 | static int block_save_live(QEMUFile *f, int stage, void *opaque) | |
312 | { | |
d11ecd3d JK |
313 | dprintf("Enter save live stage %d submitted %d transferred %d\n", |
314 | stage, block_mig_state.submitted, block_mig_state.transferred); | |
a55eb92c | 315 | |
d11ecd3d | 316 | if (block_mig_state.blk_enable != 1) { |
c163b5ca | 317 | /* no need to migrate storage */ |
a55eb92c | 318 | qemu_put_be64(f, BLK_MIG_FLAG_EOS); |
c163b5ca | 319 | return 1; |
320 | } | |
a55eb92c JK |
321 | |
322 | if (stage == 1) { | |
c163b5ca | 323 | init_blk_migration(f); |
a55eb92c | 324 | |
c163b5ca | 325 | /* start track dirty blocks */ |
326 | set_dirty_tracking(1); | |
c163b5ca | 327 | } |
328 | ||
329 | flush_blks(f); | |
a55eb92c | 330 | |
c163b5ca | 331 | /* control the rate of transfer */ |
d11ecd3d JK |
332 | while ((block_mig_state.submitted + |
333 | block_mig_state.read_done) * BLOCK_SIZE < | |
a55eb92c JK |
334 | qemu_file_get_rate_limit(f)) { |
335 | if (blk_mig_save_bulked_block(f, 1) == 0) { | |
336 | /* no more bulk blocks for now */ | |
c163b5ca | 337 | break; |
a55eb92c | 338 | } |
c163b5ca | 339 | } |
a55eb92c | 340 | |
c163b5ca | 341 | flush_blks(f); |
a55eb92c JK |
342 | |
343 | if (stage == 3) { | |
344 | while (blk_mig_save_bulked_block(f, 0) != 0) { | |
345 | /* empty */ | |
346 | } | |
347 | ||
c163b5ca | 348 | blk_mig_save_dirty_blocks(f); |
a55eb92c | 349 | |
c163b5ca | 350 | /* stop track dirty blocks */ |
a55eb92c JK |
351 | set_dirty_tracking(0); |
352 | ||
353 | printf("\nBlock migration completed\n"); | |
c163b5ca | 354 | } |
a55eb92c JK |
355 | |
356 | qemu_put_be64(f, BLK_MIG_FLAG_EOS); | |
357 | ||
c163b5ca | 358 | return ((stage == 2) && is_stage2_completed()); |
359 | } | |
360 | ||
361 | static int block_load(QEMUFile *f, void *opaque, int version_id) | |
362 | { | |
363 | int len, flags; | |
364 | char device_name[256]; | |
365 | int64_t addr; | |
366 | BlockDriverState *bs; | |
367 | uint8_t *buf; | |
a55eb92c | 368 | |
c163b5ca | 369 | do { |
c163b5ca | 370 | addr = qemu_get_be64(f); |
a55eb92c | 371 | |
6ea44308 JK |
372 | flags = addr & ~BDRV_SECTOR_MASK; |
373 | addr >>= BDRV_SECTOR_BITS; | |
a55eb92c JK |
374 | |
375 | if (flags & BLK_MIG_FLAG_DEVICE_BLOCK) { | |
c163b5ca | 376 | /* get device name */ |
377 | len = qemu_get_byte(f); | |
a55eb92c | 378 | |
c163b5ca | 379 | qemu_get_buffer(f, (uint8_t *)device_name, len); |
380 | device_name[len] = '\0'; | |
a55eb92c | 381 | |
c163b5ca | 382 | bs = bdrv_find(device_name); |
a55eb92c | 383 | |
575a58d7 JK |
384 | buf = qemu_malloc(BLOCK_SIZE); |
385 | ||
a55eb92c JK |
386 | qemu_get_buffer(f, buf, BLOCK_SIZE); |
387 | if (bs != NULL) { | |
6ea44308 | 388 | bdrv_write(bs, addr, buf, BDRV_SECTORS_PER_DIRTY_CHUNK); |
c163b5ca | 389 | } else { |
390 | printf("Error unknown block device %s\n", device_name); | |
a55eb92c | 391 | /* FIXME: add error handling */ |
c163b5ca | 392 | } |
575a58d7 JK |
393 | |
394 | qemu_free(buf); | |
a55eb92c | 395 | } else if (!(flags & BLK_MIG_FLAG_EOS)) { |
c163b5ca | 396 | printf("Unknown flags\n"); |
a55eb92c | 397 | /* FIXME: add error handling */ |
c163b5ca | 398 | } |
a55eb92c JK |
399 | } while (!(flags & BLK_MIG_FLAG_EOS)); |
400 | ||
c163b5ca | 401 | return 0; |
402 | } | |
403 | ||
404 | static void block_set_params(int blk_enable, int shared_base, void *opaque) | |
405 | { | |
d11ecd3d JK |
406 | block_mig_state.blk_enable = blk_enable; |
407 | block_mig_state.shared_base = shared_base; | |
a55eb92c | 408 | |
c163b5ca | 409 | /* shared base means that blk_enable = 1 */ |
d11ecd3d | 410 | block_mig_state.blk_enable |= shared_base; |
c163b5ca | 411 | } |
412 | ||
c163b5ca | 413 | void blk_mig_init(void) |
a55eb92c | 414 | { |
5e5328be JK |
415 | QSIMPLEQ_INIT(&block_mig_state.bmds_list); |
416 | QSIMPLEQ_INIT(&block_mig_state.blk_list); | |
417 | ||
a55eb92c | 418 | register_savevm_live("block", 0, 1, block_set_params, block_save_live, |
d11ecd3d | 419 | NULL, block_load, &block_mig_state); |
c163b5ca | 420 | } |