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Commit | Line | Data |
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61007b31 SH |
1 | /* |
2 | * Block layer I/O functions | |
3 | * | |
4 | * Copyright (c) 2003 Fabrice Bellard | |
5 | * | |
6 | * Permission is hereby granted, free of charge, to any person obtaining a copy | |
7 | * of this software and associated documentation files (the "Software"), to deal | |
8 | * in the Software without restriction, including without limitation the rights | |
9 | * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell | |
10 | * copies of the Software, and to permit persons to whom the Software is | |
11 | * furnished to do so, subject to the following conditions: | |
12 | * | |
13 | * The above copyright notice and this permission notice shall be included in | |
14 | * all copies or substantial portions of the Software. | |
15 | * | |
16 | * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR | |
17 | * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, | |
18 | * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL | |
19 | * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER | |
20 | * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, | |
21 | * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN | |
22 | * THE SOFTWARE. | |
23 | */ | |
24 | ||
80c71a24 | 25 | #include "qemu/osdep.h" |
61007b31 | 26 | #include "trace.h" |
7f0e9da6 | 27 | #include "sysemu/block-backend.h" |
7719f3c9 | 28 | #include "block/aio-wait.h" |
61007b31 | 29 | #include "block/blockjob.h" |
f321dcb5 | 30 | #include "block/blockjob_int.h" |
61007b31 | 31 | #include "block/block_int.h" |
21c2283e | 32 | #include "block/coroutines.h" |
e2c1c34f | 33 | #include "block/dirty-bitmap.h" |
94783301 | 34 | #include "block/write-threshold.h" |
f348b6d1 | 35 | #include "qemu/cutils.h" |
5df022cf | 36 | #include "qemu/memalign.h" |
da34e65c | 37 | #include "qapi/error.h" |
d49b6836 | 38 | #include "qemu/error-report.h" |
db725815 | 39 | #include "qemu/main-loop.h" |
c8aa7895 | 40 | #include "sysemu/replay.h" |
61007b31 | 41 | |
cb2e2878 EB |
42 | /* Maximum bounce buffer for copy-on-read and write zeroes, in bytes */ |
43 | #define MAX_BOUNCE_BUFFER (32768 << BDRV_SECTOR_BITS) | |
44 | ||
7f8f03ef | 45 | static void bdrv_parent_cb_resize(BlockDriverState *bs); |
d05aa8bb | 46 | static int coroutine_fn bdrv_co_do_pwrite_zeroes(BlockDriverState *bs, |
5ae07b14 | 47 | int64_t offset, int64_t bytes, BdrvRequestFlags flags); |
61007b31 | 48 | |
a82a3bd1 | 49 | static void bdrv_parent_drained_begin(BlockDriverState *bs, BdrvChild *ignore) |
61007b31 | 50 | { |
02d21300 | 51 | BdrvChild *c, *next; |
27ccdd52 | 52 | |
02d21300 | 53 | QLIST_FOREACH_SAFE(c, &bs->parents, next_parent, next) { |
a82a3bd1 | 54 | if (c == ignore) { |
0152bf40 KW |
55 | continue; |
56 | } | |
606ed756 | 57 | bdrv_parent_drained_begin_single(c); |
ce0f1412 PB |
58 | } |
59 | } | |
61007b31 | 60 | |
2f65df6e | 61 | void bdrv_parent_drained_end_single(BdrvChild *c) |
804db8ea | 62 | { |
2f65df6e KW |
63 | IO_OR_GS_CODE(); |
64 | ||
57e05be3 KW |
65 | assert(c->quiesced_parent); |
66 | c->quiesced_parent = false; | |
67 | ||
bd86fb99 | 68 | if (c->klass->drained_end) { |
2f65df6e | 69 | c->klass->drained_end(c); |
804db8ea HR |
70 | } |
71 | } | |
72 | ||
a82a3bd1 | 73 | static void bdrv_parent_drained_end(BlockDriverState *bs, BdrvChild *ignore) |
ce0f1412 | 74 | { |
61ad631c | 75 | BdrvChild *c; |
27ccdd52 | 76 | |
61ad631c | 77 | QLIST_FOREACH(c, &bs->parents, next_parent) { |
a82a3bd1 | 78 | if (c == ignore) { |
0152bf40 KW |
79 | continue; |
80 | } | |
2f65df6e | 81 | bdrv_parent_drained_end_single(c); |
27ccdd52 | 82 | } |
61007b31 SH |
83 | } |
84 | ||
23987471 | 85 | bool bdrv_parent_drained_poll_single(BdrvChild *c) |
4be6a6d1 | 86 | { |
bd86fb99 HR |
87 | if (c->klass->drained_poll) { |
88 | return c->klass->drained_poll(c); | |
4be6a6d1 KW |
89 | } |
90 | return false; | |
91 | } | |
92 | ||
6cd5c9d7 KW |
93 | static bool bdrv_parent_drained_poll(BlockDriverState *bs, BdrvChild *ignore, |
94 | bool ignore_bds_parents) | |
89bd0305 KW |
95 | { |
96 | BdrvChild *c, *next; | |
97 | bool busy = false; | |
98 | ||
99 | QLIST_FOREACH_SAFE(c, &bs->parents, next_parent, next) { | |
bd86fb99 | 100 | if (c == ignore || (ignore_bds_parents && c->klass->parent_is_bds)) { |
89bd0305 KW |
101 | continue; |
102 | } | |
4be6a6d1 | 103 | busy |= bdrv_parent_drained_poll_single(c); |
89bd0305 KW |
104 | } |
105 | ||
106 | return busy; | |
107 | } | |
108 | ||
606ed756 | 109 | void bdrv_parent_drained_begin_single(BdrvChild *c) |
4be6a6d1 | 110 | { |
384a48fb | 111 | IO_OR_GS_CODE(); |
57e05be3 KW |
112 | |
113 | assert(!c->quiesced_parent); | |
114 | c->quiesced_parent = true; | |
115 | ||
bd86fb99 HR |
116 | if (c->klass->drained_begin) { |
117 | c->klass->drained_begin(c); | |
4be6a6d1 | 118 | } |
4be6a6d1 KW |
119 | } |
120 | ||
d9e0dfa2 EB |
121 | static void bdrv_merge_limits(BlockLimits *dst, const BlockLimits *src) |
122 | { | |
9f460c64 AO |
123 | dst->pdiscard_alignment = MAX(dst->pdiscard_alignment, |
124 | src->pdiscard_alignment); | |
d9e0dfa2 EB |
125 | dst->opt_transfer = MAX(dst->opt_transfer, src->opt_transfer); |
126 | dst->max_transfer = MIN_NON_ZERO(dst->max_transfer, src->max_transfer); | |
24b36e98 PB |
127 | dst->max_hw_transfer = MIN_NON_ZERO(dst->max_hw_transfer, |
128 | src->max_hw_transfer); | |
d9e0dfa2 EB |
129 | dst->opt_mem_alignment = MAX(dst->opt_mem_alignment, |
130 | src->opt_mem_alignment); | |
131 | dst->min_mem_alignment = MAX(dst->min_mem_alignment, | |
132 | src->min_mem_alignment); | |
133 | dst->max_iov = MIN_NON_ZERO(dst->max_iov, src->max_iov); | |
cc071629 | 134 | dst->max_hw_iov = MIN_NON_ZERO(dst->max_hw_iov, src->max_hw_iov); |
d9e0dfa2 EB |
135 | } |
136 | ||
1e4c797c VSO |
137 | typedef struct BdrvRefreshLimitsState { |
138 | BlockDriverState *bs; | |
139 | BlockLimits old_bl; | |
140 | } BdrvRefreshLimitsState; | |
141 | ||
142 | static void bdrv_refresh_limits_abort(void *opaque) | |
143 | { | |
144 | BdrvRefreshLimitsState *s = opaque; | |
145 | ||
146 | s->bs->bl = s->old_bl; | |
147 | } | |
148 | ||
149 | static TransactionActionDrv bdrv_refresh_limits_drv = { | |
150 | .abort = bdrv_refresh_limits_abort, | |
151 | .clean = g_free, | |
152 | }; | |
153 | ||
154 | /* @tran is allowed to be NULL, in this case no rollback is possible. */ | |
155 | void bdrv_refresh_limits(BlockDriverState *bs, Transaction *tran, Error **errp) | |
61007b31 | 156 | { |
33985614 | 157 | ERRP_GUARD(); |
61007b31 | 158 | BlockDriver *drv = bs->drv; |
66b129ac HR |
159 | BdrvChild *c; |
160 | bool have_limits; | |
61007b31 | 161 | |
f791bf7f EGE |
162 | GLOBAL_STATE_CODE(); |
163 | ||
1e4c797c VSO |
164 | if (tran) { |
165 | BdrvRefreshLimitsState *s = g_new(BdrvRefreshLimitsState, 1); | |
166 | *s = (BdrvRefreshLimitsState) { | |
167 | .bs = bs, | |
168 | .old_bl = bs->bl, | |
169 | }; | |
170 | tran_add(tran, &bdrv_refresh_limits_drv, s); | |
171 | } | |
172 | ||
61007b31 SH |
173 | memset(&bs->bl, 0, sizeof(bs->bl)); |
174 | ||
175 | if (!drv) { | |
176 | return; | |
177 | } | |
178 | ||
79ba8c98 | 179 | /* Default alignment based on whether driver has byte interface */ |
e31f6864 | 180 | bs->bl.request_alignment = (drv->bdrv_co_preadv || |
ac850bf0 VSO |
181 | drv->bdrv_aio_preadv || |
182 | drv->bdrv_co_preadv_part) ? 1 : 512; | |
79ba8c98 | 183 | |
61007b31 | 184 | /* Take some limits from the children as a default */ |
66b129ac HR |
185 | have_limits = false; |
186 | QLIST_FOREACH(c, &bs->children, next) { | |
187 | if (c->role & (BDRV_CHILD_DATA | BDRV_CHILD_FILTERED | BDRV_CHILD_COW)) | |
188 | { | |
66b129ac HR |
189 | bdrv_merge_limits(&bs->bl, &c->bs->bl); |
190 | have_limits = true; | |
61007b31 | 191 | } |
66b129ac HR |
192 | } |
193 | ||
194 | if (!have_limits) { | |
4196d2f0 | 195 | bs->bl.min_mem_alignment = 512; |
8e3b0cbb | 196 | bs->bl.opt_mem_alignment = qemu_real_host_page_size(); |
bd44feb7 SH |
197 | |
198 | /* Safe default since most protocols use readv()/writev()/etc */ | |
199 | bs->bl.max_iov = IOV_MAX; | |
61007b31 SH |
200 | } |
201 | ||
61007b31 SH |
202 | /* Then let the driver override it */ |
203 | if (drv->bdrv_refresh_limits) { | |
204 | drv->bdrv_refresh_limits(bs, errp); | |
8b117001 VSO |
205 | if (*errp) { |
206 | return; | |
207 | } | |
208 | } | |
209 | ||
210 | if (bs->bl.request_alignment > BDRV_MAX_ALIGNMENT) { | |
211 | error_setg(errp, "Driver requires too large request alignment"); | |
61007b31 SH |
212 | } |
213 | } | |
214 | ||
215 | /** | |
216 | * The copy-on-read flag is actually a reference count so multiple users may | |
217 | * use the feature without worrying about clobbering its previous state. | |
218 | * Copy-on-read stays enabled until all users have called to disable it. | |
219 | */ | |
220 | void bdrv_enable_copy_on_read(BlockDriverState *bs) | |
221 | { | |
384a48fb | 222 | IO_CODE(); |
d73415a3 | 223 | qatomic_inc(&bs->copy_on_read); |
61007b31 SH |
224 | } |
225 | ||
226 | void bdrv_disable_copy_on_read(BlockDriverState *bs) | |
227 | { | |
d73415a3 | 228 | int old = qatomic_fetch_dec(&bs->copy_on_read); |
384a48fb | 229 | IO_CODE(); |
d3faa13e | 230 | assert(old >= 1); |
61007b31 SH |
231 | } |
232 | ||
61124f03 PB |
233 | typedef struct { |
234 | Coroutine *co; | |
235 | BlockDriverState *bs; | |
236 | bool done; | |
481cad48 | 237 | bool begin; |
fe4f0614 | 238 | bool poll; |
0152bf40 | 239 | BdrvChild *parent; |
61124f03 PB |
240 | } BdrvCoDrainData; |
241 | ||
1cc8e54a | 242 | /* Returns true if BDRV_POLL_WHILE() should go into a blocking aio_poll() */ |
299403ae KW |
243 | bool bdrv_drain_poll(BlockDriverState *bs, BdrvChild *ignore_parent, |
244 | bool ignore_bds_parents) | |
89bd0305 | 245 | { |
384a48fb | 246 | IO_OR_GS_CODE(); |
fe4f0614 | 247 | |
6cd5c9d7 | 248 | if (bdrv_parent_drained_poll(bs, ignore_parent, ignore_bds_parents)) { |
89bd0305 KW |
249 | return true; |
250 | } | |
251 | ||
d73415a3 | 252 | if (qatomic_read(&bs->in_flight)) { |
fe4f0614 KW |
253 | return true; |
254 | } | |
255 | ||
fe4f0614 | 256 | return false; |
89bd0305 KW |
257 | } |
258 | ||
299403ae | 259 | static bool bdrv_drain_poll_top_level(BlockDriverState *bs, |
89bd0305 | 260 | BdrvChild *ignore_parent) |
1cc8e54a | 261 | { |
299403ae | 262 | return bdrv_drain_poll(bs, ignore_parent, false); |
1cc8e54a KW |
263 | } |
264 | ||
299403ae | 265 | static void bdrv_do_drained_begin(BlockDriverState *bs, BdrvChild *parent, |
a82a3bd1 KW |
266 | bool poll); |
267 | static void bdrv_do_drained_end(BlockDriverState *bs, BdrvChild *parent); | |
0152bf40 | 268 | |
a77fd4bb FZ |
269 | static void bdrv_co_drain_bh_cb(void *opaque) |
270 | { | |
271 | BdrvCoDrainData *data = opaque; | |
272 | Coroutine *co = data->co; | |
99723548 | 273 | BlockDriverState *bs = data->bs; |
a77fd4bb | 274 | |
c8ca33d0 | 275 | if (bs) { |
aa1361d5 | 276 | AioContext *ctx = bdrv_get_aio_context(bs); |
960d5fb3 | 277 | aio_context_acquire(ctx); |
c8ca33d0 KW |
278 | bdrv_dec_in_flight(bs); |
279 | if (data->begin) { | |
a82a3bd1 | 280 | bdrv_do_drained_begin(bs, data->parent, data->poll); |
c8ca33d0 | 281 | } else { |
e037c09c | 282 | assert(!data->poll); |
a82a3bd1 | 283 | bdrv_do_drained_end(bs, data->parent); |
c8ca33d0 | 284 | } |
960d5fb3 | 285 | aio_context_release(ctx); |
481cad48 | 286 | } else { |
c8ca33d0 KW |
287 | assert(data->begin); |
288 | bdrv_drain_all_begin(); | |
481cad48 MP |
289 | } |
290 | ||
a77fd4bb | 291 | data->done = true; |
1919631e | 292 | aio_co_wake(co); |
a77fd4bb FZ |
293 | } |
294 | ||
481cad48 | 295 | static void coroutine_fn bdrv_co_yield_to_drain(BlockDriverState *bs, |
299403ae | 296 | bool begin, |
6cd5c9d7 | 297 | BdrvChild *parent, |
2f65df6e | 298 | bool poll) |
a77fd4bb FZ |
299 | { |
300 | BdrvCoDrainData data; | |
960d5fb3 KW |
301 | Coroutine *self = qemu_coroutine_self(); |
302 | AioContext *ctx = bdrv_get_aio_context(bs); | |
303 | AioContext *co_ctx = qemu_coroutine_get_aio_context(self); | |
a77fd4bb FZ |
304 | |
305 | /* Calling bdrv_drain() from a BH ensures the current coroutine yields and | |
c40a2545 | 306 | * other coroutines run if they were queued by aio_co_enter(). */ |
a77fd4bb FZ |
307 | |
308 | assert(qemu_in_coroutine()); | |
309 | data = (BdrvCoDrainData) { | |
960d5fb3 | 310 | .co = self, |
a77fd4bb FZ |
311 | .bs = bs, |
312 | .done = false, | |
481cad48 | 313 | .begin = begin, |
0152bf40 | 314 | .parent = parent, |
fe4f0614 | 315 | .poll = poll, |
a77fd4bb | 316 | }; |
8e1da77e | 317 | |
c8ca33d0 KW |
318 | if (bs) { |
319 | bdrv_inc_in_flight(bs); | |
320 | } | |
960d5fb3 KW |
321 | |
322 | /* | |
323 | * Temporarily drop the lock across yield or we would get deadlocks. | |
324 | * bdrv_co_drain_bh_cb() reaquires the lock as needed. | |
325 | * | |
326 | * When we yield below, the lock for the current context will be | |
327 | * released, so if this is actually the lock that protects bs, don't drop | |
328 | * it a second time. | |
329 | */ | |
330 | if (ctx != co_ctx) { | |
331 | aio_context_release(ctx); | |
332 | } | |
333 | replay_bh_schedule_oneshot_event(ctx, bdrv_co_drain_bh_cb, &data); | |
a77fd4bb FZ |
334 | |
335 | qemu_coroutine_yield(); | |
336 | /* If we are resumed from some other event (such as an aio completion or a | |
337 | * timer callback), it is a bug in the caller that should be fixed. */ | |
338 | assert(data.done); | |
960d5fb3 KW |
339 | |
340 | /* Reaquire the AioContext of bs if we dropped it */ | |
341 | if (ctx != co_ctx) { | |
342 | aio_context_acquire(ctx); | |
343 | } | |
a77fd4bb FZ |
344 | } |
345 | ||
05c272ff KW |
346 | static void bdrv_do_drained_begin(BlockDriverState *bs, BdrvChild *parent, |
347 | bool poll) | |
6820643f | 348 | { |
384a48fb | 349 | IO_OR_GS_CODE(); |
05c272ff KW |
350 | |
351 | if (qemu_in_coroutine()) { | |
352 | bdrv_co_yield_to_drain(bs, true, parent, poll); | |
353 | return; | |
354 | } | |
d42cf288 | 355 | |
60369b86 | 356 | /* Stop things in parent-to-child order */ |
d73415a3 | 357 | if (qatomic_fetch_inc(&bs->quiesce_counter) == 0) { |
6820643f | 358 | aio_disable_external(bdrv_get_aio_context(bs)); |
a82a3bd1 | 359 | bdrv_parent_drained_begin(bs, parent); |
57e05be3 KW |
360 | if (bs->drv && bs->drv->bdrv_drain_begin) { |
361 | bs->drv->bdrv_drain_begin(bs); | |
362 | } | |
c7bc05f7 | 363 | } |
d30b8e64 | 364 | |
fe4f0614 KW |
365 | /* |
366 | * Wait for drained requests to finish. | |
367 | * | |
368 | * Calling BDRV_POLL_WHILE() only once for the top-level node is okay: The | |
369 | * call is needed so things in this AioContext can make progress even | |
370 | * though we don't return to the main AioContext loop - this automatically | |
371 | * includes other nodes in the same AioContext and therefore all child | |
372 | * nodes. | |
373 | */ | |
374 | if (poll) { | |
299403ae | 375 | BDRV_POLL_WHILE(bs, bdrv_drain_poll_top_level(bs, parent)); |
fe4f0614 | 376 | } |
6820643f KW |
377 | } |
378 | ||
05c272ff KW |
379 | void bdrv_do_drained_begin_quiesce(BlockDriverState *bs, BdrvChild *parent) |
380 | { | |
381 | bdrv_do_drained_begin(bs, parent, false); | |
382 | } | |
383 | ||
0152bf40 KW |
384 | void bdrv_drained_begin(BlockDriverState *bs) |
385 | { | |
384a48fb | 386 | IO_OR_GS_CODE(); |
a82a3bd1 | 387 | bdrv_do_drained_begin(bs, NULL, true); |
0152bf40 KW |
388 | } |
389 | ||
e037c09c HR |
390 | /** |
391 | * This function does not poll, nor must any of its recursively called | |
2f65df6e | 392 | * functions. |
e037c09c | 393 | */ |
a82a3bd1 | 394 | static void bdrv_do_drained_end(BlockDriverState *bs, BdrvChild *parent) |
6820643f | 395 | { |
0f115168 KW |
396 | int old_quiesce_counter; |
397 | ||
481cad48 | 398 | if (qemu_in_coroutine()) { |
a82a3bd1 | 399 | bdrv_co_yield_to_drain(bs, false, parent, false); |
481cad48 MP |
400 | return; |
401 | } | |
6820643f | 402 | assert(bs->quiesce_counter > 0); |
6820643f | 403 | |
60369b86 | 404 | /* Re-enable things in child-to-parent order */ |
d73415a3 | 405 | old_quiesce_counter = qatomic_fetch_dec(&bs->quiesce_counter); |
0f115168 | 406 | if (old_quiesce_counter == 1) { |
57e05be3 KW |
407 | if (bs->drv && bs->drv->bdrv_drain_end) { |
408 | bs->drv->bdrv_drain_end(bs); | |
409 | } | |
a82a3bd1 | 410 | bdrv_parent_drained_end(bs, parent); |
0f115168 KW |
411 | aio_enable_external(bdrv_get_aio_context(bs)); |
412 | } | |
6820643f KW |
413 | } |
414 | ||
0152bf40 KW |
415 | void bdrv_drained_end(BlockDriverState *bs) |
416 | { | |
384a48fb | 417 | IO_OR_GS_CODE(); |
a82a3bd1 | 418 | bdrv_do_drained_end(bs, NULL); |
d736f119 KW |
419 | } |
420 | ||
b6e84c97 PB |
421 | void bdrv_drain(BlockDriverState *bs) |
422 | { | |
384a48fb | 423 | IO_OR_GS_CODE(); |
6820643f KW |
424 | bdrv_drained_begin(bs); |
425 | bdrv_drained_end(bs); | |
61007b31 SH |
426 | } |
427 | ||
c13ad59f KW |
428 | static void bdrv_drain_assert_idle(BlockDriverState *bs) |
429 | { | |
430 | BdrvChild *child, *next; | |
431 | ||
d73415a3 | 432 | assert(qatomic_read(&bs->in_flight) == 0); |
c13ad59f KW |
433 | QLIST_FOREACH_SAFE(child, &bs->children, next, next) { |
434 | bdrv_drain_assert_idle(child->bs); | |
435 | } | |
436 | } | |
437 | ||
0f12264e KW |
438 | unsigned int bdrv_drain_all_count = 0; |
439 | ||
440 | static bool bdrv_drain_all_poll(void) | |
441 | { | |
442 | BlockDriverState *bs = NULL; | |
443 | bool result = false; | |
f791bf7f | 444 | GLOBAL_STATE_CODE(); |
0f12264e | 445 | |
0f12264e KW |
446 | /* bdrv_drain_poll() can't make changes to the graph and we are holding the |
447 | * main AioContext lock, so iterating bdrv_next_all_states() is safe. */ | |
448 | while ((bs = bdrv_next_all_states(bs))) { | |
449 | AioContext *aio_context = bdrv_get_aio_context(bs); | |
450 | aio_context_acquire(aio_context); | |
299403ae | 451 | result |= bdrv_drain_poll(bs, NULL, true); |
0f12264e KW |
452 | aio_context_release(aio_context); |
453 | } | |
454 | ||
455 | return result; | |
456 | } | |
457 | ||
61007b31 SH |
458 | /* |
459 | * Wait for pending requests to complete across all BlockDriverStates | |
460 | * | |
461 | * This function does not flush data to disk, use bdrv_flush_all() for that | |
462 | * after calling this function. | |
c0778f66 AG |
463 | * |
464 | * This pauses all block jobs and disables external clients. It must | |
465 | * be paired with bdrv_drain_all_end(). | |
466 | * | |
467 | * NOTE: no new block jobs or BlockDriverStates can be created between | |
468 | * the bdrv_drain_all_begin() and bdrv_drain_all_end() calls. | |
61007b31 | 469 | */ |
da0bd744 | 470 | void bdrv_drain_all_begin_nopoll(void) |
61007b31 | 471 | { |
0f12264e | 472 | BlockDriverState *bs = NULL; |
f791bf7f | 473 | GLOBAL_STATE_CODE(); |
61007b31 | 474 | |
c8aa7895 PD |
475 | /* |
476 | * bdrv queue is managed by record/replay, | |
477 | * waiting for finishing the I/O requests may | |
478 | * be infinite | |
479 | */ | |
480 | if (replay_events_enabled()) { | |
481 | return; | |
482 | } | |
483 | ||
0f12264e KW |
484 | /* AIO_WAIT_WHILE() with a NULL context can only be called from the main |
485 | * loop AioContext, so make sure we're in the main context. */ | |
9a7e86c8 | 486 | assert(qemu_get_current_aio_context() == qemu_get_aio_context()); |
0f12264e KW |
487 | assert(bdrv_drain_all_count < INT_MAX); |
488 | bdrv_drain_all_count++; | |
9a7e86c8 | 489 | |
0f12264e KW |
490 | /* Quiesce all nodes, without polling in-flight requests yet. The graph |
491 | * cannot change during this loop. */ | |
492 | while ((bs = bdrv_next_all_states(bs))) { | |
61007b31 SH |
493 | AioContext *aio_context = bdrv_get_aio_context(bs); |
494 | ||
495 | aio_context_acquire(aio_context); | |
a82a3bd1 | 496 | bdrv_do_drained_begin(bs, NULL, false); |
61007b31 SH |
497 | aio_context_release(aio_context); |
498 | } | |
da0bd744 KW |
499 | } |
500 | ||
501 | void bdrv_drain_all_begin(void) | |
502 | { | |
503 | BlockDriverState *bs = NULL; | |
504 | ||
505 | if (qemu_in_coroutine()) { | |
506 | bdrv_co_yield_to_drain(NULL, true, NULL, true); | |
507 | return; | |
508 | } | |
509 | ||
63945789 PM |
510 | /* |
511 | * bdrv queue is managed by record/replay, | |
512 | * waiting for finishing the I/O requests may | |
513 | * be infinite | |
514 | */ | |
515 | if (replay_events_enabled()) { | |
516 | return; | |
517 | } | |
518 | ||
da0bd744 | 519 | bdrv_drain_all_begin_nopoll(); |
61007b31 | 520 | |
0f12264e | 521 | /* Now poll the in-flight requests */ |
cfe29d82 | 522 | AIO_WAIT_WHILE(NULL, bdrv_drain_all_poll()); |
0f12264e KW |
523 | |
524 | while ((bs = bdrv_next_all_states(bs))) { | |
c13ad59f | 525 | bdrv_drain_assert_idle(bs); |
61007b31 | 526 | } |
c0778f66 AG |
527 | } |
528 | ||
1a6d3bd2 GK |
529 | void bdrv_drain_all_end_quiesce(BlockDriverState *bs) |
530 | { | |
b4ad82aa | 531 | GLOBAL_STATE_CODE(); |
1a6d3bd2 GK |
532 | |
533 | g_assert(bs->quiesce_counter > 0); | |
534 | g_assert(!bs->refcnt); | |
535 | ||
536 | while (bs->quiesce_counter) { | |
a82a3bd1 | 537 | bdrv_do_drained_end(bs, NULL); |
1a6d3bd2 | 538 | } |
1a6d3bd2 GK |
539 | } |
540 | ||
c0778f66 AG |
541 | void bdrv_drain_all_end(void) |
542 | { | |
0f12264e | 543 | BlockDriverState *bs = NULL; |
f791bf7f | 544 | GLOBAL_STATE_CODE(); |
c0778f66 | 545 | |
c8aa7895 PD |
546 | /* |
547 | * bdrv queue is managed by record/replay, | |
548 | * waiting for finishing the I/O requests may | |
549 | * be endless | |
550 | */ | |
551 | if (replay_events_enabled()) { | |
552 | return; | |
553 | } | |
554 | ||
0f12264e | 555 | while ((bs = bdrv_next_all_states(bs))) { |
61007b31 SH |
556 | AioContext *aio_context = bdrv_get_aio_context(bs); |
557 | ||
558 | aio_context_acquire(aio_context); | |
a82a3bd1 | 559 | bdrv_do_drained_end(bs, NULL); |
61007b31 SH |
560 | aio_context_release(aio_context); |
561 | } | |
0f12264e | 562 | |
e037c09c | 563 | assert(qemu_get_current_aio_context() == qemu_get_aio_context()); |
0f12264e KW |
564 | assert(bdrv_drain_all_count > 0); |
565 | bdrv_drain_all_count--; | |
61007b31 SH |
566 | } |
567 | ||
c0778f66 AG |
568 | void bdrv_drain_all(void) |
569 | { | |
f791bf7f | 570 | GLOBAL_STATE_CODE(); |
c0778f66 AG |
571 | bdrv_drain_all_begin(); |
572 | bdrv_drain_all_end(); | |
573 | } | |
574 | ||
61007b31 SH |
575 | /** |
576 | * Remove an active request from the tracked requests list | |
577 | * | |
578 | * This function should be called when a tracked request is completing. | |
579 | */ | |
f0d43b1e | 580 | static void coroutine_fn tracked_request_end(BdrvTrackedRequest *req) |
61007b31 SH |
581 | { |
582 | if (req->serialising) { | |
d73415a3 | 583 | qatomic_dec(&req->bs->serialising_in_flight); |
61007b31 SH |
584 | } |
585 | ||
3783fa3d | 586 | qemu_co_mutex_lock(&req->bs->reqs_lock); |
61007b31 SH |
587 | QLIST_REMOVE(req, list); |
588 | qemu_co_queue_restart_all(&req->wait_queue); | |
3783fa3d | 589 | qemu_co_mutex_unlock(&req->bs->reqs_lock); |
61007b31 SH |
590 | } |
591 | ||
592 | /** | |
593 | * Add an active request to the tracked requests list | |
594 | */ | |
881a4c55 PB |
595 | static void coroutine_fn tracked_request_begin(BdrvTrackedRequest *req, |
596 | BlockDriverState *bs, | |
597 | int64_t offset, | |
598 | int64_t bytes, | |
599 | enum BdrvTrackedRequestType type) | |
61007b31 | 600 | { |
80247264 | 601 | bdrv_check_request(offset, bytes, &error_abort); |
22931a15 | 602 | |
61007b31 SH |
603 | *req = (BdrvTrackedRequest){ |
604 | .bs = bs, | |
605 | .offset = offset, | |
606 | .bytes = bytes, | |
ebde595c | 607 | .type = type, |
61007b31 SH |
608 | .co = qemu_coroutine_self(), |
609 | .serialising = false, | |
610 | .overlap_offset = offset, | |
611 | .overlap_bytes = bytes, | |
612 | }; | |
613 | ||
614 | qemu_co_queue_init(&req->wait_queue); | |
615 | ||
3783fa3d | 616 | qemu_co_mutex_lock(&bs->reqs_lock); |
61007b31 | 617 | QLIST_INSERT_HEAD(&bs->tracked_requests, req, list); |
3783fa3d | 618 | qemu_co_mutex_unlock(&bs->reqs_lock); |
61007b31 SH |
619 | } |
620 | ||
3ba0e1a0 | 621 | static bool tracked_request_overlaps(BdrvTrackedRequest *req, |
80247264 | 622 | int64_t offset, int64_t bytes) |
3ba0e1a0 | 623 | { |
80247264 EB |
624 | bdrv_check_request(offset, bytes, &error_abort); |
625 | ||
3ba0e1a0 PB |
626 | /* aaaa bbbb */ |
627 | if (offset >= req->overlap_offset + req->overlap_bytes) { | |
628 | return false; | |
629 | } | |
630 | /* bbbb aaaa */ | |
631 | if (req->overlap_offset >= offset + bytes) { | |
632 | return false; | |
633 | } | |
634 | return true; | |
635 | } | |
636 | ||
3183937f | 637 | /* Called with self->bs->reqs_lock held */ |
881a4c55 | 638 | static coroutine_fn BdrvTrackedRequest * |
3183937f VSO |
639 | bdrv_find_conflicting_request(BdrvTrackedRequest *self) |
640 | { | |
641 | BdrvTrackedRequest *req; | |
642 | ||
643 | QLIST_FOREACH(req, &self->bs->tracked_requests, list) { | |
644 | if (req == self || (!req->serialising && !self->serialising)) { | |
645 | continue; | |
646 | } | |
647 | if (tracked_request_overlaps(req, self->overlap_offset, | |
648 | self->overlap_bytes)) | |
649 | { | |
650 | /* | |
651 | * Hitting this means there was a reentrant request, for | |
652 | * example, a block driver issuing nested requests. This must | |
653 | * never happen since it means deadlock. | |
654 | */ | |
655 | assert(qemu_coroutine_self() != req->co); | |
656 | ||
657 | /* | |
658 | * If the request is already (indirectly) waiting for us, or | |
659 | * will wait for us as soon as it wakes up, then just go on | |
660 | * (instead of producing a deadlock in the former case). | |
661 | */ | |
662 | if (!req->waiting_for) { | |
663 | return req; | |
664 | } | |
665 | } | |
666 | } | |
667 | ||
668 | return NULL; | |
669 | } | |
670 | ||
ec1c8868 | 671 | /* Called with self->bs->reqs_lock held */ |
131498f7 | 672 | static void coroutine_fn |
ec1c8868 | 673 | bdrv_wait_serialising_requests_locked(BdrvTrackedRequest *self) |
3ba0e1a0 PB |
674 | { |
675 | BdrvTrackedRequest *req; | |
3ba0e1a0 | 676 | |
3183937f VSO |
677 | while ((req = bdrv_find_conflicting_request(self))) { |
678 | self->waiting_for = req; | |
ec1c8868 | 679 | qemu_co_queue_wait(&req->wait_queue, &self->bs->reqs_lock); |
3183937f | 680 | self->waiting_for = NULL; |
3183937f | 681 | } |
3ba0e1a0 PB |
682 | } |
683 | ||
8ac5aab2 VSO |
684 | /* Called with req->bs->reqs_lock held */ |
685 | static void tracked_request_set_serialising(BdrvTrackedRequest *req, | |
686 | uint64_t align) | |
61007b31 SH |
687 | { |
688 | int64_t overlap_offset = req->offset & ~(align - 1); | |
80247264 EB |
689 | int64_t overlap_bytes = |
690 | ROUND_UP(req->offset + req->bytes, align) - overlap_offset; | |
691 | ||
692 | bdrv_check_request(req->offset, req->bytes, &error_abort); | |
61007b31 SH |
693 | |
694 | if (!req->serialising) { | |
d73415a3 | 695 | qatomic_inc(&req->bs->serialising_in_flight); |
61007b31 SH |
696 | req->serialising = true; |
697 | } | |
698 | ||
699 | req->overlap_offset = MIN(req->overlap_offset, overlap_offset); | |
700 | req->overlap_bytes = MAX(req->overlap_bytes, overlap_bytes); | |
09d2f948 VSO |
701 | } |
702 | ||
c28107e9 HR |
703 | /** |
704 | * Return the tracked request on @bs for the current coroutine, or | |
705 | * NULL if there is none. | |
706 | */ | |
707 | BdrvTrackedRequest *coroutine_fn bdrv_co_get_self_request(BlockDriverState *bs) | |
708 | { | |
709 | BdrvTrackedRequest *req; | |
710 | Coroutine *self = qemu_coroutine_self(); | |
967d7905 | 711 | IO_CODE(); |
c28107e9 HR |
712 | |
713 | QLIST_FOREACH(req, &bs->tracked_requests, list) { | |
714 | if (req->co == self) { | |
715 | return req; | |
716 | } | |
717 | } | |
718 | ||
719 | return NULL; | |
720 | } | |
721 | ||
244483e6 KW |
722 | /** |
723 | * Round a region to cluster boundaries | |
724 | */ | |
725 | void bdrv_round_to_clusters(BlockDriverState *bs, | |
7cfd5275 | 726 | int64_t offset, int64_t bytes, |
244483e6 | 727 | int64_t *cluster_offset, |
7cfd5275 | 728 | int64_t *cluster_bytes) |
244483e6 KW |
729 | { |
730 | BlockDriverInfo bdi; | |
384a48fb | 731 | IO_CODE(); |
244483e6 KW |
732 | if (bdrv_get_info(bs, &bdi) < 0 || bdi.cluster_size == 0) { |
733 | *cluster_offset = offset; | |
734 | *cluster_bytes = bytes; | |
735 | } else { | |
736 | int64_t c = bdi.cluster_size; | |
737 | *cluster_offset = QEMU_ALIGN_DOWN(offset, c); | |
738 | *cluster_bytes = QEMU_ALIGN_UP(offset - *cluster_offset + bytes, c); | |
739 | } | |
740 | } | |
741 | ||
61007b31 SH |
742 | static int bdrv_get_cluster_size(BlockDriverState *bs) |
743 | { | |
744 | BlockDriverInfo bdi; | |
745 | int ret; | |
746 | ||
747 | ret = bdrv_get_info(bs, &bdi); | |
748 | if (ret < 0 || bdi.cluster_size == 0) { | |
a5b8dd2c | 749 | return bs->bl.request_alignment; |
61007b31 SH |
750 | } else { |
751 | return bdi.cluster_size; | |
752 | } | |
753 | } | |
754 | ||
99723548 PB |
755 | void bdrv_inc_in_flight(BlockDriverState *bs) |
756 | { | |
967d7905 | 757 | IO_CODE(); |
d73415a3 | 758 | qatomic_inc(&bs->in_flight); |
99723548 PB |
759 | } |
760 | ||
c9d1a561 PB |
761 | void bdrv_wakeup(BlockDriverState *bs) |
762 | { | |
967d7905 | 763 | IO_CODE(); |
cfe29d82 | 764 | aio_wait_kick(); |
c9d1a561 PB |
765 | } |
766 | ||
99723548 PB |
767 | void bdrv_dec_in_flight(BlockDriverState *bs) |
768 | { | |
967d7905 | 769 | IO_CODE(); |
d73415a3 | 770 | qatomic_dec(&bs->in_flight); |
c9d1a561 | 771 | bdrv_wakeup(bs); |
99723548 PB |
772 | } |
773 | ||
131498f7 DL |
774 | static void coroutine_fn |
775 | bdrv_wait_serialising_requests(BdrvTrackedRequest *self) | |
61007b31 SH |
776 | { |
777 | BlockDriverState *bs = self->bs; | |
61007b31 | 778 | |
d73415a3 | 779 | if (!qatomic_read(&bs->serialising_in_flight)) { |
131498f7 | 780 | return; |
61007b31 SH |
781 | } |
782 | ||
3ba0e1a0 | 783 | qemu_co_mutex_lock(&bs->reqs_lock); |
131498f7 | 784 | bdrv_wait_serialising_requests_locked(self); |
3ba0e1a0 | 785 | qemu_co_mutex_unlock(&bs->reqs_lock); |
61007b31 SH |
786 | } |
787 | ||
131498f7 | 788 | void coroutine_fn bdrv_make_request_serialising(BdrvTrackedRequest *req, |
8ac5aab2 VSO |
789 | uint64_t align) |
790 | { | |
967d7905 | 791 | IO_CODE(); |
8ac5aab2 VSO |
792 | |
793 | qemu_co_mutex_lock(&req->bs->reqs_lock); | |
794 | ||
795 | tracked_request_set_serialising(req, align); | |
131498f7 | 796 | bdrv_wait_serialising_requests_locked(req); |
8ac5aab2 VSO |
797 | |
798 | qemu_co_mutex_unlock(&req->bs->reqs_lock); | |
8ac5aab2 VSO |
799 | } |
800 | ||
558902cc VSO |
801 | int bdrv_check_qiov_request(int64_t offset, int64_t bytes, |
802 | QEMUIOVector *qiov, size_t qiov_offset, | |
803 | Error **errp) | |
61007b31 | 804 | { |
63f4ad11 VSO |
805 | /* |
806 | * Check generic offset/bytes correctness | |
807 | */ | |
808 | ||
69b55e03 VSO |
809 | if (offset < 0) { |
810 | error_setg(errp, "offset is negative: %" PRIi64, offset); | |
811 | return -EIO; | |
812 | } | |
813 | ||
814 | if (bytes < 0) { | |
815 | error_setg(errp, "bytes is negative: %" PRIi64, bytes); | |
61007b31 SH |
816 | return -EIO; |
817 | } | |
818 | ||
8b117001 | 819 | if (bytes > BDRV_MAX_LENGTH) { |
69b55e03 VSO |
820 | error_setg(errp, "bytes(%" PRIi64 ") exceeds maximum(%" PRIi64 ")", |
821 | bytes, BDRV_MAX_LENGTH); | |
822 | return -EIO; | |
823 | } | |
824 | ||
825 | if (offset > BDRV_MAX_LENGTH) { | |
826 | error_setg(errp, "offset(%" PRIi64 ") exceeds maximum(%" PRIi64 ")", | |
827 | offset, BDRV_MAX_LENGTH); | |
8b117001 VSO |
828 | return -EIO; |
829 | } | |
830 | ||
831 | if (offset > BDRV_MAX_LENGTH - bytes) { | |
69b55e03 VSO |
832 | error_setg(errp, "sum of offset(%" PRIi64 ") and bytes(%" PRIi64 ") " |
833 | "exceeds maximum(%" PRIi64 ")", offset, bytes, | |
834 | BDRV_MAX_LENGTH); | |
8b117001 VSO |
835 | return -EIO; |
836 | } | |
837 | ||
63f4ad11 VSO |
838 | if (!qiov) { |
839 | return 0; | |
840 | } | |
841 | ||
842 | /* | |
843 | * Check qiov and qiov_offset | |
844 | */ | |
845 | ||
846 | if (qiov_offset > qiov->size) { | |
847 | error_setg(errp, "qiov_offset(%zu) overflow io vector size(%zu)", | |
848 | qiov_offset, qiov->size); | |
849 | return -EIO; | |
850 | } | |
851 | ||
852 | if (bytes > qiov->size - qiov_offset) { | |
853 | error_setg(errp, "bytes(%" PRIi64 ") + qiov_offset(%zu) overflow io " | |
854 | "vector size(%zu)", bytes, qiov_offset, qiov->size); | |
855 | return -EIO; | |
856 | } | |
857 | ||
8b117001 VSO |
858 | return 0; |
859 | } | |
860 | ||
63f4ad11 VSO |
861 | int bdrv_check_request(int64_t offset, int64_t bytes, Error **errp) |
862 | { | |
863 | return bdrv_check_qiov_request(offset, bytes, NULL, 0, errp); | |
864 | } | |
865 | ||
866 | static int bdrv_check_request32(int64_t offset, int64_t bytes, | |
867 | QEMUIOVector *qiov, size_t qiov_offset) | |
8b117001 | 868 | { |
63f4ad11 | 869 | int ret = bdrv_check_qiov_request(offset, bytes, qiov, qiov_offset, NULL); |
8b117001 VSO |
870 | if (ret < 0) { |
871 | return ret; | |
872 | } | |
873 | ||
874 | if (bytes > BDRV_REQUEST_MAX_BYTES) { | |
61007b31 SH |
875 | return -EIO; |
876 | } | |
877 | ||
878 | return 0; | |
879 | } | |
880 | ||
61007b31 | 881 | /* |
74021bc4 | 882 | * Completely zero out a block device with the help of bdrv_pwrite_zeroes. |
61007b31 SH |
883 | * The operation is sped up by checking the block status and only writing |
884 | * zeroes to the device if they currently do not return zeroes. Optional | |
74021bc4 | 885 | * flags are passed through to bdrv_pwrite_zeroes (e.g. BDRV_REQ_MAY_UNMAP, |
465fe887 | 886 | * BDRV_REQ_FUA). |
61007b31 | 887 | * |
f4649069 | 888 | * Returns < 0 on error, 0 on success. For error codes see bdrv_pwrite(). |
61007b31 | 889 | */ |
720ff280 | 890 | int bdrv_make_zero(BdrvChild *child, BdrvRequestFlags flags) |
61007b31 | 891 | { |
237d78f8 EB |
892 | int ret; |
893 | int64_t target_size, bytes, offset = 0; | |
720ff280 | 894 | BlockDriverState *bs = child->bs; |
384a48fb | 895 | IO_CODE(); |
61007b31 | 896 | |
7286d610 EB |
897 | target_size = bdrv_getlength(bs); |
898 | if (target_size < 0) { | |
899 | return target_size; | |
61007b31 SH |
900 | } |
901 | ||
902 | for (;;) { | |
7286d610 EB |
903 | bytes = MIN(target_size - offset, BDRV_REQUEST_MAX_BYTES); |
904 | if (bytes <= 0) { | |
61007b31 SH |
905 | return 0; |
906 | } | |
237d78f8 | 907 | ret = bdrv_block_status(bs, offset, bytes, &bytes, NULL, NULL); |
61007b31 | 908 | if (ret < 0) { |
61007b31 SH |
909 | return ret; |
910 | } | |
911 | if (ret & BDRV_BLOCK_ZERO) { | |
237d78f8 | 912 | offset += bytes; |
61007b31 SH |
913 | continue; |
914 | } | |
237d78f8 | 915 | ret = bdrv_pwrite_zeroes(child, offset, bytes, flags); |
61007b31 | 916 | if (ret < 0) { |
61007b31 SH |
917 | return ret; |
918 | } | |
237d78f8 | 919 | offset += bytes; |
61007b31 SH |
920 | } |
921 | } | |
922 | ||
61007b31 SH |
923 | /* |
924 | * Writes to the file and ensures that no writes are reordered across this | |
925 | * request (acts as a barrier) | |
926 | * | |
927 | * Returns 0 on success, -errno in error cases. | |
928 | */ | |
e97190a4 AF |
929 | int coroutine_fn bdrv_co_pwrite_sync(BdrvChild *child, int64_t offset, |
930 | int64_t bytes, const void *buf, | |
931 | BdrvRequestFlags flags) | |
61007b31 SH |
932 | { |
933 | int ret; | |
384a48fb | 934 | IO_CODE(); |
61007b31 | 935 | |
e97190a4 | 936 | ret = bdrv_co_pwrite(child, offset, bytes, buf, flags); |
61007b31 SH |
937 | if (ret < 0) { |
938 | return ret; | |
939 | } | |
940 | ||
e97190a4 | 941 | ret = bdrv_co_flush(child->bs); |
855a6a93 KW |
942 | if (ret < 0) { |
943 | return ret; | |
61007b31 SH |
944 | } |
945 | ||
946 | return 0; | |
947 | } | |
948 | ||
08844473 KW |
949 | typedef struct CoroutineIOCompletion { |
950 | Coroutine *coroutine; | |
951 | int ret; | |
952 | } CoroutineIOCompletion; | |
953 | ||
954 | static void bdrv_co_io_em_complete(void *opaque, int ret) | |
955 | { | |
956 | CoroutineIOCompletion *co = opaque; | |
957 | ||
958 | co->ret = ret; | |
b9e413dd | 959 | aio_co_wake(co->coroutine); |
08844473 KW |
960 | } |
961 | ||
166fe960 | 962 | static int coroutine_fn bdrv_driver_preadv(BlockDriverState *bs, |
17abcbee | 963 | int64_t offset, int64_t bytes, |
ac850bf0 VSO |
964 | QEMUIOVector *qiov, |
965 | size_t qiov_offset, int flags) | |
166fe960 KW |
966 | { |
967 | BlockDriver *drv = bs->drv; | |
3fb06697 KW |
968 | int64_t sector_num; |
969 | unsigned int nb_sectors; | |
ac850bf0 VSO |
970 | QEMUIOVector local_qiov; |
971 | int ret; | |
3fb06697 | 972 | |
17abcbee | 973 | bdrv_check_qiov_request(offset, bytes, qiov, qiov_offset, &error_abort); |
e8b65355 | 974 | assert(!(flags & ~bs->supported_read_flags)); |
fa166538 | 975 | |
d470ad42 HR |
976 | if (!drv) { |
977 | return -ENOMEDIUM; | |
978 | } | |
979 | ||
ac850bf0 VSO |
980 | if (drv->bdrv_co_preadv_part) { |
981 | return drv->bdrv_co_preadv_part(bs, offset, bytes, qiov, qiov_offset, | |
982 | flags); | |
983 | } | |
984 | ||
985 | if (qiov_offset > 0 || bytes != qiov->size) { | |
986 | qemu_iovec_init_slice(&local_qiov, qiov, qiov_offset, bytes); | |
987 | qiov = &local_qiov; | |
988 | } | |
989 | ||
3fb06697 | 990 | if (drv->bdrv_co_preadv) { |
ac850bf0 VSO |
991 | ret = drv->bdrv_co_preadv(bs, offset, bytes, qiov, flags); |
992 | goto out; | |
3fb06697 KW |
993 | } |
994 | ||
edfab6a0 | 995 | if (drv->bdrv_aio_preadv) { |
08844473 KW |
996 | BlockAIOCB *acb; |
997 | CoroutineIOCompletion co = { | |
998 | .coroutine = qemu_coroutine_self(), | |
999 | }; | |
1000 | ||
edfab6a0 EB |
1001 | acb = drv->bdrv_aio_preadv(bs, offset, bytes, qiov, flags, |
1002 | bdrv_co_io_em_complete, &co); | |
08844473 | 1003 | if (acb == NULL) { |
ac850bf0 VSO |
1004 | ret = -EIO; |
1005 | goto out; | |
08844473 KW |
1006 | } else { |
1007 | qemu_coroutine_yield(); | |
ac850bf0 VSO |
1008 | ret = co.ret; |
1009 | goto out; | |
08844473 KW |
1010 | } |
1011 | } | |
edfab6a0 EB |
1012 | |
1013 | sector_num = offset >> BDRV_SECTOR_BITS; | |
1014 | nb_sectors = bytes >> BDRV_SECTOR_BITS; | |
1015 | ||
1bbbf32d NS |
1016 | assert(QEMU_IS_ALIGNED(offset, BDRV_SECTOR_SIZE)); |
1017 | assert(QEMU_IS_ALIGNED(bytes, BDRV_SECTOR_SIZE)); | |
41ae31e3 | 1018 | assert(bytes <= BDRV_REQUEST_MAX_BYTES); |
edfab6a0 EB |
1019 | assert(drv->bdrv_co_readv); |
1020 | ||
ac850bf0 VSO |
1021 | ret = drv->bdrv_co_readv(bs, sector_num, nb_sectors, qiov); |
1022 | ||
1023 | out: | |
1024 | if (qiov == &local_qiov) { | |
1025 | qemu_iovec_destroy(&local_qiov); | |
1026 | } | |
1027 | ||
1028 | return ret; | |
166fe960 KW |
1029 | } |
1030 | ||
78a07294 | 1031 | static int coroutine_fn bdrv_driver_pwritev(BlockDriverState *bs, |
17abcbee | 1032 | int64_t offset, int64_t bytes, |
ac850bf0 | 1033 | QEMUIOVector *qiov, |
e75abeda VSO |
1034 | size_t qiov_offset, |
1035 | BdrvRequestFlags flags) | |
78a07294 KW |
1036 | { |
1037 | BlockDriver *drv = bs->drv; | |
e8b65355 | 1038 | bool emulate_fua = false; |
3fb06697 KW |
1039 | int64_t sector_num; |
1040 | unsigned int nb_sectors; | |
ac850bf0 | 1041 | QEMUIOVector local_qiov; |
78a07294 KW |
1042 | int ret; |
1043 | ||
17abcbee | 1044 | bdrv_check_qiov_request(offset, bytes, qiov, qiov_offset, &error_abort); |
fa166538 | 1045 | |
d470ad42 HR |
1046 | if (!drv) { |
1047 | return -ENOMEDIUM; | |
1048 | } | |
1049 | ||
e8b65355 SH |
1050 | if ((flags & BDRV_REQ_FUA) && |
1051 | (~bs->supported_write_flags & BDRV_REQ_FUA)) { | |
1052 | flags &= ~BDRV_REQ_FUA; | |
1053 | emulate_fua = true; | |
1054 | } | |
1055 | ||
1056 | flags &= bs->supported_write_flags; | |
1057 | ||
ac850bf0 VSO |
1058 | if (drv->bdrv_co_pwritev_part) { |
1059 | ret = drv->bdrv_co_pwritev_part(bs, offset, bytes, qiov, qiov_offset, | |
e8b65355 | 1060 | flags); |
ac850bf0 VSO |
1061 | goto emulate_flags; |
1062 | } | |
1063 | ||
1064 | if (qiov_offset > 0 || bytes != qiov->size) { | |
1065 | qemu_iovec_init_slice(&local_qiov, qiov, qiov_offset, bytes); | |
1066 | qiov = &local_qiov; | |
1067 | } | |
1068 | ||
3fb06697 | 1069 | if (drv->bdrv_co_pwritev) { |
e8b65355 | 1070 | ret = drv->bdrv_co_pwritev(bs, offset, bytes, qiov, flags); |
3fb06697 KW |
1071 | goto emulate_flags; |
1072 | } | |
1073 | ||
edfab6a0 | 1074 | if (drv->bdrv_aio_pwritev) { |
08844473 KW |
1075 | BlockAIOCB *acb; |
1076 | CoroutineIOCompletion co = { | |
1077 | .coroutine = qemu_coroutine_self(), | |
1078 | }; | |
1079 | ||
e8b65355 | 1080 | acb = drv->bdrv_aio_pwritev(bs, offset, bytes, qiov, flags, |
edfab6a0 | 1081 | bdrv_co_io_em_complete, &co); |
08844473 | 1082 | if (acb == NULL) { |
3fb06697 | 1083 | ret = -EIO; |
08844473 KW |
1084 | } else { |
1085 | qemu_coroutine_yield(); | |
3fb06697 | 1086 | ret = co.ret; |
08844473 | 1087 | } |
edfab6a0 EB |
1088 | goto emulate_flags; |
1089 | } | |
1090 | ||
1091 | sector_num = offset >> BDRV_SECTOR_BITS; | |
1092 | nb_sectors = bytes >> BDRV_SECTOR_BITS; | |
1093 | ||
1bbbf32d NS |
1094 | assert(QEMU_IS_ALIGNED(offset, BDRV_SECTOR_SIZE)); |
1095 | assert(QEMU_IS_ALIGNED(bytes, BDRV_SECTOR_SIZE)); | |
41ae31e3 | 1096 | assert(bytes <= BDRV_REQUEST_MAX_BYTES); |
edfab6a0 | 1097 | |
e18a58b4 | 1098 | assert(drv->bdrv_co_writev); |
e8b65355 | 1099 | ret = drv->bdrv_co_writev(bs, sector_num, nb_sectors, qiov, flags); |
78a07294 | 1100 | |
3fb06697 | 1101 | emulate_flags: |
e8b65355 | 1102 | if (ret == 0 && emulate_fua) { |
78a07294 KW |
1103 | ret = bdrv_co_flush(bs); |
1104 | } | |
1105 | ||
ac850bf0 VSO |
1106 | if (qiov == &local_qiov) { |
1107 | qemu_iovec_destroy(&local_qiov); | |
1108 | } | |
1109 | ||
78a07294 KW |
1110 | return ret; |
1111 | } | |
1112 | ||
29a298af | 1113 | static int coroutine_fn |
17abcbee VSO |
1114 | bdrv_driver_pwritev_compressed(BlockDriverState *bs, int64_t offset, |
1115 | int64_t bytes, QEMUIOVector *qiov, | |
ac850bf0 | 1116 | size_t qiov_offset) |
29a298af PB |
1117 | { |
1118 | BlockDriver *drv = bs->drv; | |
ac850bf0 VSO |
1119 | QEMUIOVector local_qiov; |
1120 | int ret; | |
29a298af | 1121 | |
17abcbee VSO |
1122 | bdrv_check_qiov_request(offset, bytes, qiov, qiov_offset, &error_abort); |
1123 | ||
d470ad42 HR |
1124 | if (!drv) { |
1125 | return -ENOMEDIUM; | |
1126 | } | |
1127 | ||
ac850bf0 | 1128 | if (!block_driver_can_compress(drv)) { |
29a298af PB |
1129 | return -ENOTSUP; |
1130 | } | |
1131 | ||
ac850bf0 VSO |
1132 | if (drv->bdrv_co_pwritev_compressed_part) { |
1133 | return drv->bdrv_co_pwritev_compressed_part(bs, offset, bytes, | |
1134 | qiov, qiov_offset); | |
1135 | } | |
1136 | ||
1137 | if (qiov_offset == 0) { | |
1138 | return drv->bdrv_co_pwritev_compressed(bs, offset, bytes, qiov); | |
1139 | } | |
1140 | ||
1141 | qemu_iovec_init_slice(&local_qiov, qiov, qiov_offset, bytes); | |
1142 | ret = drv->bdrv_co_pwritev_compressed(bs, offset, bytes, &local_qiov); | |
1143 | qemu_iovec_destroy(&local_qiov); | |
1144 | ||
1145 | return ret; | |
29a298af PB |
1146 | } |
1147 | ||
85c97ca7 | 1148 | static int coroutine_fn bdrv_co_do_copy_on_readv(BdrvChild *child, |
9df5afbd | 1149 | int64_t offset, int64_t bytes, QEMUIOVector *qiov, |
1143ec5e | 1150 | size_t qiov_offset, int flags) |
61007b31 | 1151 | { |
85c97ca7 KW |
1152 | BlockDriverState *bs = child->bs; |
1153 | ||
61007b31 SH |
1154 | /* Perform I/O through a temporary buffer so that users who scribble over |
1155 | * their read buffer while the operation is in progress do not end up | |
1156 | * modifying the image file. This is critical for zero-copy guest I/O | |
1157 | * where anything might happen inside guest memory. | |
1158 | */ | |
2275cc90 | 1159 | void *bounce_buffer = NULL; |
61007b31 SH |
1160 | |
1161 | BlockDriver *drv = bs->drv; | |
244483e6 | 1162 | int64_t cluster_offset; |
7cfd5275 | 1163 | int64_t cluster_bytes; |
9df5afbd | 1164 | int64_t skip_bytes; |
61007b31 | 1165 | int ret; |
cb2e2878 EB |
1166 | int max_transfer = MIN_NON_ZERO(bs->bl.max_transfer, |
1167 | BDRV_REQUEST_MAX_BYTES); | |
9df5afbd | 1168 | int64_t progress = 0; |
8644476e | 1169 | bool skip_write; |
61007b31 | 1170 | |
9df5afbd VSO |
1171 | bdrv_check_qiov_request(offset, bytes, qiov, qiov_offset, &error_abort); |
1172 | ||
d470ad42 HR |
1173 | if (!drv) { |
1174 | return -ENOMEDIUM; | |
1175 | } | |
1176 | ||
8644476e HR |
1177 | /* |
1178 | * Do not write anything when the BDS is inactive. That is not | |
1179 | * allowed, and it would not help. | |
1180 | */ | |
1181 | skip_write = (bs->open_flags & BDRV_O_INACTIVE); | |
1182 | ||
1bf03e66 KW |
1183 | /* FIXME We cannot require callers to have write permissions when all they |
1184 | * are doing is a read request. If we did things right, write permissions | |
1185 | * would be obtained anyway, but internally by the copy-on-read code. As | |
765d9df9 | 1186 | * long as it is implemented here rather than in a separate filter driver, |
1bf03e66 KW |
1187 | * the copy-on-read code doesn't have its own BdrvChild, however, for which |
1188 | * it could request permissions. Therefore we have to bypass the permission | |
1189 | * system for the moment. */ | |
1190 | // assert(child->perm & (BLK_PERM_WRITE_UNCHANGED | BLK_PERM_WRITE)); | |
afa4b293 | 1191 | |
61007b31 | 1192 | /* Cover entire cluster so no additional backing file I/O is required when |
cb2e2878 EB |
1193 | * allocating cluster in the image file. Note that this value may exceed |
1194 | * BDRV_REQUEST_MAX_BYTES (even when the original read did not), which | |
1195 | * is one reason we loop rather than doing it all at once. | |
61007b31 | 1196 | */ |
244483e6 | 1197 | bdrv_round_to_clusters(bs, offset, bytes, &cluster_offset, &cluster_bytes); |
cb2e2878 | 1198 | skip_bytes = offset - cluster_offset; |
61007b31 | 1199 | |
244483e6 KW |
1200 | trace_bdrv_co_do_copy_on_readv(bs, offset, bytes, |
1201 | cluster_offset, cluster_bytes); | |
61007b31 | 1202 | |
cb2e2878 EB |
1203 | while (cluster_bytes) { |
1204 | int64_t pnum; | |
61007b31 | 1205 | |
8644476e HR |
1206 | if (skip_write) { |
1207 | ret = 1; /* "already allocated", so nothing will be copied */ | |
cb2e2878 | 1208 | pnum = MIN(cluster_bytes, max_transfer); |
8644476e HR |
1209 | } else { |
1210 | ret = bdrv_is_allocated(bs, cluster_offset, | |
1211 | MIN(cluster_bytes, max_transfer), &pnum); | |
1212 | if (ret < 0) { | |
1213 | /* | |
1214 | * Safe to treat errors in querying allocation as if | |
1215 | * unallocated; we'll probably fail again soon on the | |
1216 | * read, but at least that will set a decent errno. | |
1217 | */ | |
1218 | pnum = MIN(cluster_bytes, max_transfer); | |
1219 | } | |
61007b31 | 1220 | |
8644476e HR |
1221 | /* Stop at EOF if the image ends in the middle of the cluster */ |
1222 | if (ret == 0 && pnum == 0) { | |
1223 | assert(progress >= bytes); | |
1224 | break; | |
1225 | } | |
b0ddcbbb | 1226 | |
8644476e HR |
1227 | assert(skip_bytes < pnum); |
1228 | } | |
61007b31 | 1229 | |
cb2e2878 | 1230 | if (ret <= 0) { |
1143ec5e VSO |
1231 | QEMUIOVector local_qiov; |
1232 | ||
cb2e2878 | 1233 | /* Must copy-on-read; use the bounce buffer */ |
0d93ed08 | 1234 | pnum = MIN(pnum, MAX_BOUNCE_BUFFER); |
2275cc90 VSO |
1235 | if (!bounce_buffer) { |
1236 | int64_t max_we_need = MAX(pnum, cluster_bytes - pnum); | |
1237 | int64_t max_allowed = MIN(max_transfer, MAX_BOUNCE_BUFFER); | |
1238 | int64_t bounce_buffer_len = MIN(max_we_need, max_allowed); | |
1239 | ||
1240 | bounce_buffer = qemu_try_blockalign(bs, bounce_buffer_len); | |
1241 | if (!bounce_buffer) { | |
1242 | ret = -ENOMEM; | |
1243 | goto err; | |
1244 | } | |
1245 | } | |
0d93ed08 | 1246 | qemu_iovec_init_buf(&local_qiov, bounce_buffer, pnum); |
61007b31 | 1247 | |
cb2e2878 | 1248 | ret = bdrv_driver_preadv(bs, cluster_offset, pnum, |
ac850bf0 | 1249 | &local_qiov, 0, 0); |
cb2e2878 EB |
1250 | if (ret < 0) { |
1251 | goto err; | |
1252 | } | |
1253 | ||
1254 | bdrv_debug_event(bs, BLKDBG_COR_WRITE); | |
1255 | if (drv->bdrv_co_pwrite_zeroes && | |
1256 | buffer_is_zero(bounce_buffer, pnum)) { | |
1257 | /* FIXME: Should we (perhaps conditionally) be setting | |
1258 | * BDRV_REQ_MAY_UNMAP, if it will allow for a sparser copy | |
1259 | * that still correctly reads as zero? */ | |
7adcf59f HR |
1260 | ret = bdrv_co_do_pwrite_zeroes(bs, cluster_offset, pnum, |
1261 | BDRV_REQ_WRITE_UNCHANGED); | |
cb2e2878 EB |
1262 | } else { |
1263 | /* This does not change the data on the disk, it is not | |
1264 | * necessary to flush even in cache=writethrough mode. | |
1265 | */ | |
1266 | ret = bdrv_driver_pwritev(bs, cluster_offset, pnum, | |
ac850bf0 | 1267 | &local_qiov, 0, |
7adcf59f | 1268 | BDRV_REQ_WRITE_UNCHANGED); |
cb2e2878 EB |
1269 | } |
1270 | ||
1271 | if (ret < 0) { | |
1272 | /* It might be okay to ignore write errors for guest | |
1273 | * requests. If this is a deliberate copy-on-read | |
1274 | * then we don't want to ignore the error. Simply | |
1275 | * report it in all cases. | |
1276 | */ | |
1277 | goto err; | |
1278 | } | |
1279 | ||
3299e5ec | 1280 | if (!(flags & BDRV_REQ_PREFETCH)) { |
1143ec5e VSO |
1281 | qemu_iovec_from_buf(qiov, qiov_offset + progress, |
1282 | bounce_buffer + skip_bytes, | |
4ab78b19 | 1283 | MIN(pnum - skip_bytes, bytes - progress)); |
3299e5ec VSO |
1284 | } |
1285 | } else if (!(flags & BDRV_REQ_PREFETCH)) { | |
cb2e2878 | 1286 | /* Read directly into the destination */ |
1143ec5e VSO |
1287 | ret = bdrv_driver_preadv(bs, offset + progress, |
1288 | MIN(pnum - skip_bytes, bytes - progress), | |
1289 | qiov, qiov_offset + progress, 0); | |
cb2e2878 EB |
1290 | if (ret < 0) { |
1291 | goto err; | |
1292 | } | |
1293 | } | |
1294 | ||
1295 | cluster_offset += pnum; | |
1296 | cluster_bytes -= pnum; | |
1297 | progress += pnum - skip_bytes; | |
1298 | skip_bytes = 0; | |
1299 | } | |
1300 | ret = 0; | |
61007b31 SH |
1301 | |
1302 | err: | |
1303 | qemu_vfree(bounce_buffer); | |
1304 | return ret; | |
1305 | } | |
1306 | ||
1307 | /* | |
1308 | * Forwards an already correctly aligned request to the BlockDriver. This | |
1a62d0ac EB |
1309 | * handles copy on read, zeroing after EOF, and fragmentation of large |
1310 | * reads; any other features must be implemented by the caller. | |
61007b31 | 1311 | */ |
85c97ca7 | 1312 | static int coroutine_fn bdrv_aligned_preadv(BdrvChild *child, |
8b0c5d76 | 1313 | BdrvTrackedRequest *req, int64_t offset, int64_t bytes, |
65cd4424 | 1314 | int64_t align, QEMUIOVector *qiov, size_t qiov_offset, int flags) |
61007b31 | 1315 | { |
85c97ca7 | 1316 | BlockDriverState *bs = child->bs; |
c9d20029 | 1317 | int64_t total_bytes, max_bytes; |
1a62d0ac | 1318 | int ret = 0; |
8b0c5d76 | 1319 | int64_t bytes_remaining = bytes; |
1a62d0ac | 1320 | int max_transfer; |
61007b31 | 1321 | |
8b0c5d76 | 1322 | bdrv_check_qiov_request(offset, bytes, qiov, qiov_offset, &error_abort); |
49c07526 KW |
1323 | assert(is_power_of_2(align)); |
1324 | assert((offset & (align - 1)) == 0); | |
1325 | assert((bytes & (align - 1)) == 0); | |
abb06c5a | 1326 | assert((bs->open_flags & BDRV_O_NO_IO) == 0); |
1a62d0ac EB |
1327 | max_transfer = QEMU_ALIGN_DOWN(MIN_NON_ZERO(bs->bl.max_transfer, INT_MAX), |
1328 | align); | |
a604fa2b | 1329 | |
e8b65355 SH |
1330 | /* |
1331 | * TODO: We would need a per-BDS .supported_read_flags and | |
a604fa2b EB |
1332 | * potential fallback support, if we ever implement any read flags |
1333 | * to pass through to drivers. For now, there aren't any | |
e8b65355 SH |
1334 | * passthrough flags except the BDRV_REQ_REGISTERED_BUF optimization hint. |
1335 | */ | |
1336 | assert(!(flags & ~(BDRV_REQ_COPY_ON_READ | BDRV_REQ_PREFETCH | | |
1337 | BDRV_REQ_REGISTERED_BUF))); | |
61007b31 SH |
1338 | |
1339 | /* Handle Copy on Read and associated serialisation */ | |
1340 | if (flags & BDRV_REQ_COPY_ON_READ) { | |
1341 | /* If we touch the same cluster it counts as an overlap. This | |
1342 | * guarantees that allocating writes will be serialized and not race | |
1343 | * with each other for the same cluster. For example, in copy-on-read | |
1344 | * it ensures that the CoR read and write operations are atomic and | |
1345 | * guest writes cannot interleave between them. */ | |
8ac5aab2 | 1346 | bdrv_make_request_serialising(req, bdrv_get_cluster_size(bs)); |
18fbd0de PB |
1347 | } else { |
1348 | bdrv_wait_serialising_requests(req); | |
61007b31 SH |
1349 | } |
1350 | ||
61007b31 | 1351 | if (flags & BDRV_REQ_COPY_ON_READ) { |
d6a644bb | 1352 | int64_t pnum; |
61007b31 | 1353 | |
897dd0ec AS |
1354 | /* The flag BDRV_REQ_COPY_ON_READ has reached its addressee */ |
1355 | flags &= ~BDRV_REQ_COPY_ON_READ; | |
1356 | ||
88e63df2 | 1357 | ret = bdrv_is_allocated(bs, offset, bytes, &pnum); |
61007b31 SH |
1358 | if (ret < 0) { |
1359 | goto out; | |
1360 | } | |
1361 | ||
88e63df2 | 1362 | if (!ret || pnum != bytes) { |
65cd4424 VSO |
1363 | ret = bdrv_co_do_copy_on_readv(child, offset, bytes, |
1364 | qiov, qiov_offset, flags); | |
3299e5ec VSO |
1365 | goto out; |
1366 | } else if (flags & BDRV_REQ_PREFETCH) { | |
61007b31 SH |
1367 | goto out; |
1368 | } | |
1369 | } | |
1370 | ||
1a62d0ac | 1371 | /* Forward the request to the BlockDriver, possibly fragmenting it */ |
c9d20029 KW |
1372 | total_bytes = bdrv_getlength(bs); |
1373 | if (total_bytes < 0) { | |
1374 | ret = total_bytes; | |
1375 | goto out; | |
1376 | } | |
61007b31 | 1377 | |
e8b65355 | 1378 | assert(!(flags & ~(bs->supported_read_flags | BDRV_REQ_REGISTERED_BUF))); |
897dd0ec | 1379 | |
c9d20029 | 1380 | max_bytes = ROUND_UP(MAX(0, total_bytes - offset), align); |
1a62d0ac | 1381 | if (bytes <= max_bytes && bytes <= max_transfer) { |
897dd0ec | 1382 | ret = bdrv_driver_preadv(bs, offset, bytes, qiov, qiov_offset, flags); |
1a62d0ac EB |
1383 | goto out; |
1384 | } | |
61007b31 | 1385 | |
1a62d0ac | 1386 | while (bytes_remaining) { |
8b0c5d76 | 1387 | int64_t num; |
61007b31 | 1388 | |
1a62d0ac | 1389 | if (max_bytes) { |
1a62d0ac EB |
1390 | num = MIN(bytes_remaining, MIN(max_bytes, max_transfer)); |
1391 | assert(num); | |
61007b31 | 1392 | |
1a62d0ac | 1393 | ret = bdrv_driver_preadv(bs, offset + bytes - bytes_remaining, |
134b7dec | 1394 | num, qiov, |
897dd0ec AS |
1395 | qiov_offset + bytes - bytes_remaining, |
1396 | flags); | |
1a62d0ac | 1397 | max_bytes -= num; |
1a62d0ac EB |
1398 | } else { |
1399 | num = bytes_remaining; | |
134b7dec HR |
1400 | ret = qemu_iovec_memset(qiov, qiov_offset + bytes - bytes_remaining, |
1401 | 0, bytes_remaining); | |
1a62d0ac EB |
1402 | } |
1403 | if (ret < 0) { | |
1404 | goto out; | |
1405 | } | |
1406 | bytes_remaining -= num; | |
61007b31 SH |
1407 | } |
1408 | ||
1409 | out: | |
1a62d0ac | 1410 | return ret < 0 ? ret : 0; |
61007b31 SH |
1411 | } |
1412 | ||
61007b31 | 1413 | /* |
7a3f542f VSO |
1414 | * Request padding |
1415 | * | |
1416 | * |<---- align ----->| |<----- align ---->| | |
1417 | * |<- head ->|<------------- bytes ------------->|<-- tail -->| | |
1418 | * | | | | | | | |
1419 | * -*----------$-------*-------- ... --------*-----$------------*--- | |
1420 | * | | | | | | | |
1421 | * | offset | | end | | |
1422 | * ALIGN_DOWN(offset) ALIGN_UP(offset) ALIGN_DOWN(end) ALIGN_UP(end) | |
1423 | * [buf ... ) [tail_buf ) | |
1424 | * | |
1425 | * @buf is an aligned allocation needed to store @head and @tail paddings. @head | |
1426 | * is placed at the beginning of @buf and @tail at the @end. | |
1427 | * | |
1428 | * @tail_buf is a pointer to sub-buffer, corresponding to align-sized chunk | |
1429 | * around tail, if tail exists. | |
1430 | * | |
1431 | * @merge_reads is true for small requests, | |
1432 | * if @buf_len == @head + bytes + @tail. In this case it is possible that both | |
1433 | * head and tail exist but @buf_len == align and @tail_buf == @buf. | |
1434 | */ | |
1435 | typedef struct BdrvRequestPadding { | |
1436 | uint8_t *buf; | |
1437 | size_t buf_len; | |
1438 | uint8_t *tail_buf; | |
1439 | size_t head; | |
1440 | size_t tail; | |
1441 | bool merge_reads; | |
1442 | QEMUIOVector local_qiov; | |
1443 | } BdrvRequestPadding; | |
1444 | ||
1445 | static bool bdrv_init_padding(BlockDriverState *bs, | |
1446 | int64_t offset, int64_t bytes, | |
1447 | BdrvRequestPadding *pad) | |
1448 | { | |
a56ed80c VSO |
1449 | int64_t align = bs->bl.request_alignment; |
1450 | int64_t sum; | |
1451 | ||
1452 | bdrv_check_request(offset, bytes, &error_abort); | |
1453 | assert(align <= INT_MAX); /* documented in block/block_int.h */ | |
1454 | assert(align <= SIZE_MAX / 2); /* so we can allocate the buffer */ | |
7a3f542f VSO |
1455 | |
1456 | memset(pad, 0, sizeof(*pad)); | |
1457 | ||
1458 | pad->head = offset & (align - 1); | |
1459 | pad->tail = ((offset + bytes) & (align - 1)); | |
1460 | if (pad->tail) { | |
1461 | pad->tail = align - pad->tail; | |
1462 | } | |
1463 | ||
ac9d00bf | 1464 | if (!pad->head && !pad->tail) { |
7a3f542f VSO |
1465 | return false; |
1466 | } | |
1467 | ||
ac9d00bf VSO |
1468 | assert(bytes); /* Nothing good in aligning zero-length requests */ |
1469 | ||
7a3f542f VSO |
1470 | sum = pad->head + bytes + pad->tail; |
1471 | pad->buf_len = (sum > align && pad->head && pad->tail) ? 2 * align : align; | |
1472 | pad->buf = qemu_blockalign(bs, pad->buf_len); | |
1473 | pad->merge_reads = sum == pad->buf_len; | |
1474 | if (pad->tail) { | |
1475 | pad->tail_buf = pad->buf + pad->buf_len - align; | |
1476 | } | |
1477 | ||
1478 | return true; | |
1479 | } | |
1480 | ||
881a4c55 PB |
1481 | static coroutine_fn int bdrv_padding_rmw_read(BdrvChild *child, |
1482 | BdrvTrackedRequest *req, | |
1483 | BdrvRequestPadding *pad, | |
1484 | bool zero_middle) | |
7a3f542f VSO |
1485 | { |
1486 | QEMUIOVector local_qiov; | |
1487 | BlockDriverState *bs = child->bs; | |
1488 | uint64_t align = bs->bl.request_alignment; | |
1489 | int ret; | |
1490 | ||
1491 | assert(req->serialising && pad->buf); | |
1492 | ||
1493 | if (pad->head || pad->merge_reads) { | |
8b0c5d76 | 1494 | int64_t bytes = pad->merge_reads ? pad->buf_len : align; |
7a3f542f VSO |
1495 | |
1496 | qemu_iovec_init_buf(&local_qiov, pad->buf, bytes); | |
1497 | ||
1498 | if (pad->head) { | |
1499 | bdrv_debug_event(bs, BLKDBG_PWRITEV_RMW_HEAD); | |
1500 | } | |
1501 | if (pad->merge_reads && pad->tail) { | |
1502 | bdrv_debug_event(bs, BLKDBG_PWRITEV_RMW_TAIL); | |
1503 | } | |
1504 | ret = bdrv_aligned_preadv(child, req, req->overlap_offset, bytes, | |
65cd4424 | 1505 | align, &local_qiov, 0, 0); |
7a3f542f VSO |
1506 | if (ret < 0) { |
1507 | return ret; | |
1508 | } | |
1509 | if (pad->head) { | |
1510 | bdrv_debug_event(bs, BLKDBG_PWRITEV_RMW_AFTER_HEAD); | |
1511 | } | |
1512 | if (pad->merge_reads && pad->tail) { | |
1513 | bdrv_debug_event(bs, BLKDBG_PWRITEV_RMW_AFTER_TAIL); | |
1514 | } | |
1515 | ||
1516 | if (pad->merge_reads) { | |
1517 | goto zero_mem; | |
1518 | } | |
1519 | } | |
1520 | ||
1521 | if (pad->tail) { | |
1522 | qemu_iovec_init_buf(&local_qiov, pad->tail_buf, align); | |
1523 | ||
1524 | bdrv_debug_event(bs, BLKDBG_PWRITEV_RMW_TAIL); | |
1525 | ret = bdrv_aligned_preadv( | |
1526 | child, req, | |
1527 | req->overlap_offset + req->overlap_bytes - align, | |
65cd4424 | 1528 | align, align, &local_qiov, 0, 0); |
7a3f542f VSO |
1529 | if (ret < 0) { |
1530 | return ret; | |
1531 | } | |
1532 | bdrv_debug_event(bs, BLKDBG_PWRITEV_RMW_AFTER_TAIL); | |
1533 | } | |
1534 | ||
1535 | zero_mem: | |
1536 | if (zero_middle) { | |
1537 | memset(pad->buf + pad->head, 0, pad->buf_len - pad->head - pad->tail); | |
1538 | } | |
1539 | ||
1540 | return 0; | |
1541 | } | |
1542 | ||
1543 | static void bdrv_padding_destroy(BdrvRequestPadding *pad) | |
1544 | { | |
1545 | if (pad->buf) { | |
1546 | qemu_vfree(pad->buf); | |
1547 | qemu_iovec_destroy(&pad->local_qiov); | |
1548 | } | |
98ca4549 | 1549 | memset(pad, 0, sizeof(*pad)); |
7a3f542f VSO |
1550 | } |
1551 | ||
1552 | /* | |
1553 | * bdrv_pad_request | |
1554 | * | |
1555 | * Exchange request parameters with padded request if needed. Don't include RMW | |
1556 | * read of padding, bdrv_padding_rmw_read() should be called separately if | |
1557 | * needed. | |
1558 | * | |
98ca4549 VSO |
1559 | * Request parameters (@qiov, &qiov_offset, &offset, &bytes) are in-out: |
1560 | * - on function start they represent original request | |
1561 | * - on failure or when padding is not needed they are unchanged | |
1562 | * - on success when padding is needed they represent padded request | |
61007b31 | 1563 | */ |
98ca4549 VSO |
1564 | static int bdrv_pad_request(BlockDriverState *bs, |
1565 | QEMUIOVector **qiov, size_t *qiov_offset, | |
37e9403e | 1566 | int64_t *offset, int64_t *bytes, |
e8b65355 SH |
1567 | BdrvRequestPadding *pad, bool *padded, |
1568 | BdrvRequestFlags *flags) | |
7a3f542f | 1569 | { |
4c002cef VSO |
1570 | int ret; |
1571 | ||
37e9403e VSO |
1572 | bdrv_check_qiov_request(*offset, *bytes, *qiov, *qiov_offset, &error_abort); |
1573 | ||
7a3f542f | 1574 | if (!bdrv_init_padding(bs, *offset, *bytes, pad)) { |
98ca4549 VSO |
1575 | if (padded) { |
1576 | *padded = false; | |
1577 | } | |
1578 | return 0; | |
7a3f542f VSO |
1579 | } |
1580 | ||
4c002cef VSO |
1581 | ret = qemu_iovec_init_extended(&pad->local_qiov, pad->buf, pad->head, |
1582 | *qiov, *qiov_offset, *bytes, | |
1583 | pad->buf + pad->buf_len - pad->tail, | |
1584 | pad->tail); | |
98ca4549 VSO |
1585 | if (ret < 0) { |
1586 | bdrv_padding_destroy(pad); | |
1587 | return ret; | |
1588 | } | |
7a3f542f VSO |
1589 | *bytes += pad->head + pad->tail; |
1590 | *offset -= pad->head; | |
1591 | *qiov = &pad->local_qiov; | |
1acc3466 | 1592 | *qiov_offset = 0; |
98ca4549 VSO |
1593 | if (padded) { |
1594 | *padded = true; | |
1595 | } | |
e8b65355 SH |
1596 | if (flags) { |
1597 | /* Can't use optimization hint with bounce buffer */ | |
1598 | *flags &= ~BDRV_REQ_REGISTERED_BUF; | |
1599 | } | |
7a3f542f | 1600 | |
98ca4549 | 1601 | return 0; |
7a3f542f VSO |
1602 | } |
1603 | ||
a03ef88f | 1604 | int coroutine_fn bdrv_co_preadv(BdrvChild *child, |
e9e52efd | 1605 | int64_t offset, int64_t bytes, QEMUIOVector *qiov, |
61007b31 | 1606 | BdrvRequestFlags flags) |
1acc3466 | 1607 | { |
967d7905 | 1608 | IO_CODE(); |
1acc3466 VSO |
1609 | return bdrv_co_preadv_part(child, offset, bytes, qiov, 0, flags); |
1610 | } | |
1611 | ||
1612 | int coroutine_fn bdrv_co_preadv_part(BdrvChild *child, | |
37e9403e | 1613 | int64_t offset, int64_t bytes, |
1acc3466 VSO |
1614 | QEMUIOVector *qiov, size_t qiov_offset, |
1615 | BdrvRequestFlags flags) | |
61007b31 | 1616 | { |
a03ef88f | 1617 | BlockDriverState *bs = child->bs; |
61007b31 | 1618 | BdrvTrackedRequest req; |
7a3f542f | 1619 | BdrvRequestPadding pad; |
61007b31 | 1620 | int ret; |
967d7905 | 1621 | IO_CODE(); |
61007b31 | 1622 | |
37e9403e | 1623 | trace_bdrv_co_preadv_part(bs, offset, bytes, flags); |
61007b31 | 1624 | |
1e97be91 | 1625 | if (!bdrv_co_is_inserted(bs)) { |
f4dad307 VSO |
1626 | return -ENOMEDIUM; |
1627 | } | |
1628 | ||
63f4ad11 | 1629 | ret = bdrv_check_request32(offset, bytes, qiov, qiov_offset); |
61007b31 SH |
1630 | if (ret < 0) { |
1631 | return ret; | |
1632 | } | |
1633 | ||
ac9d00bf VSO |
1634 | if (bytes == 0 && !QEMU_IS_ALIGNED(offset, bs->bl.request_alignment)) { |
1635 | /* | |
1636 | * Aligning zero request is nonsense. Even if driver has special meaning | |
1637 | * of zero-length (like qcow2_co_pwritev_compressed_part), we can't pass | |
1638 | * it to driver due to request_alignment. | |
1639 | * | |
1640 | * Still, no reason to return an error if someone do unaligned | |
1641 | * zero-length read occasionally. | |
1642 | */ | |
1643 | return 0; | |
1644 | } | |
1645 | ||
99723548 PB |
1646 | bdrv_inc_in_flight(bs); |
1647 | ||
9568b511 | 1648 | /* Don't do copy-on-read if we read data before write operation */ |
d73415a3 | 1649 | if (qatomic_read(&bs->copy_on_read)) { |
61007b31 SH |
1650 | flags |= BDRV_REQ_COPY_ON_READ; |
1651 | } | |
1652 | ||
98ca4549 | 1653 | ret = bdrv_pad_request(bs, &qiov, &qiov_offset, &offset, &bytes, &pad, |
e8b65355 | 1654 | NULL, &flags); |
98ca4549 | 1655 | if (ret < 0) { |
87ab8802 | 1656 | goto fail; |
98ca4549 | 1657 | } |
61007b31 | 1658 | |
ebde595c | 1659 | tracked_request_begin(&req, bs, offset, bytes, BDRV_TRACKED_READ); |
7a3f542f VSO |
1660 | ret = bdrv_aligned_preadv(child, &req, offset, bytes, |
1661 | bs->bl.request_alignment, | |
1acc3466 | 1662 | qiov, qiov_offset, flags); |
61007b31 | 1663 | tracked_request_end(&req); |
7a3f542f | 1664 | bdrv_padding_destroy(&pad); |
61007b31 | 1665 | |
87ab8802 KW |
1666 | fail: |
1667 | bdrv_dec_in_flight(bs); | |
1668 | ||
61007b31 SH |
1669 | return ret; |
1670 | } | |
1671 | ||
d05aa8bb | 1672 | static int coroutine_fn bdrv_co_do_pwrite_zeroes(BlockDriverState *bs, |
5ae07b14 | 1673 | int64_t offset, int64_t bytes, BdrvRequestFlags flags) |
61007b31 SH |
1674 | { |
1675 | BlockDriver *drv = bs->drv; | |
1676 | QEMUIOVector qiov; | |
0d93ed08 | 1677 | void *buf = NULL; |
61007b31 | 1678 | int ret = 0; |
465fe887 | 1679 | bool need_flush = false; |
443668ca DL |
1680 | int head = 0; |
1681 | int tail = 0; | |
61007b31 | 1682 | |
2aaa3f9b VSO |
1683 | int64_t max_write_zeroes = MIN_NON_ZERO(bs->bl.max_pwrite_zeroes, |
1684 | INT64_MAX); | |
a5b8dd2c EB |
1685 | int alignment = MAX(bs->bl.pwrite_zeroes_alignment, |
1686 | bs->bl.request_alignment); | |
cb2e2878 | 1687 | int max_transfer = MIN_NON_ZERO(bs->bl.max_transfer, MAX_BOUNCE_BUFFER); |
d05aa8bb | 1688 | |
5ae07b14 VSO |
1689 | bdrv_check_request(offset, bytes, &error_abort); |
1690 | ||
d470ad42 HR |
1691 | if (!drv) { |
1692 | return -ENOMEDIUM; | |
1693 | } | |
1694 | ||
fe0480d6 KW |
1695 | if ((flags & ~bs->supported_zero_flags) & BDRV_REQ_NO_FALLBACK) { |
1696 | return -ENOTSUP; | |
1697 | } | |
1698 | ||
e8b65355 SH |
1699 | /* By definition there is no user buffer so this flag doesn't make sense */ |
1700 | if (flags & BDRV_REQ_REGISTERED_BUF) { | |
1701 | return -EINVAL; | |
1702 | } | |
1703 | ||
0bc329fb HR |
1704 | /* Invalidate the cached block-status data range if this write overlaps */ |
1705 | bdrv_bsc_invalidate_range(bs, offset, bytes); | |
1706 | ||
b8d0a980 EB |
1707 | assert(alignment % bs->bl.request_alignment == 0); |
1708 | head = offset % alignment; | |
f5a5ca79 | 1709 | tail = (offset + bytes) % alignment; |
b8d0a980 EB |
1710 | max_write_zeroes = QEMU_ALIGN_DOWN(max_write_zeroes, alignment); |
1711 | assert(max_write_zeroes >= bs->bl.request_alignment); | |
61007b31 | 1712 | |
f5a5ca79 | 1713 | while (bytes > 0 && !ret) { |
5ae07b14 | 1714 | int64_t num = bytes; |
61007b31 SH |
1715 | |
1716 | /* Align request. Block drivers can expect the "bulk" of the request | |
443668ca DL |
1717 | * to be aligned, and that unaligned requests do not cross cluster |
1718 | * boundaries. | |
61007b31 | 1719 | */ |
443668ca | 1720 | if (head) { |
b2f95fee EB |
1721 | /* Make a small request up to the first aligned sector. For |
1722 | * convenience, limit this request to max_transfer even if | |
1723 | * we don't need to fall back to writes. */ | |
f5a5ca79 | 1724 | num = MIN(MIN(bytes, max_transfer), alignment - head); |
b2f95fee EB |
1725 | head = (head + num) % alignment; |
1726 | assert(num < max_write_zeroes); | |
d05aa8bb | 1727 | } else if (tail && num > alignment) { |
443668ca DL |
1728 | /* Shorten the request to the last aligned sector. */ |
1729 | num -= tail; | |
61007b31 SH |
1730 | } |
1731 | ||
1732 | /* limit request size */ | |
1733 | if (num > max_write_zeroes) { | |
1734 | num = max_write_zeroes; | |
1735 | } | |
1736 | ||
1737 | ret = -ENOTSUP; | |
1738 | /* First try the efficient write zeroes operation */ | |
d05aa8bb EB |
1739 | if (drv->bdrv_co_pwrite_zeroes) { |
1740 | ret = drv->bdrv_co_pwrite_zeroes(bs, offset, num, | |
1741 | flags & bs->supported_zero_flags); | |
1742 | if (ret != -ENOTSUP && (flags & BDRV_REQ_FUA) && | |
1743 | !(bs->supported_zero_flags & BDRV_REQ_FUA)) { | |
1744 | need_flush = true; | |
1745 | } | |
465fe887 EB |
1746 | } else { |
1747 | assert(!bs->supported_zero_flags); | |
61007b31 SH |
1748 | } |
1749 | ||
294682cc | 1750 | if (ret == -ENOTSUP && !(flags & BDRV_REQ_NO_FALLBACK)) { |
61007b31 | 1751 | /* Fall back to bounce buffer if write zeroes is unsupported */ |
465fe887 EB |
1752 | BdrvRequestFlags write_flags = flags & ~BDRV_REQ_ZERO_WRITE; |
1753 | ||
1754 | if ((flags & BDRV_REQ_FUA) && | |
1755 | !(bs->supported_write_flags & BDRV_REQ_FUA)) { | |
1756 | /* No need for bdrv_driver_pwrite() to do a fallback | |
1757 | * flush on each chunk; use just one at the end */ | |
1758 | write_flags &= ~BDRV_REQ_FUA; | |
1759 | need_flush = true; | |
1760 | } | |
5def6b80 | 1761 | num = MIN(num, max_transfer); |
0d93ed08 VSO |
1762 | if (buf == NULL) { |
1763 | buf = qemu_try_blockalign0(bs, num); | |
1764 | if (buf == NULL) { | |
61007b31 SH |
1765 | ret = -ENOMEM; |
1766 | goto fail; | |
1767 | } | |
61007b31 | 1768 | } |
0d93ed08 | 1769 | qemu_iovec_init_buf(&qiov, buf, num); |
61007b31 | 1770 | |
ac850bf0 | 1771 | ret = bdrv_driver_pwritev(bs, offset, num, &qiov, 0, write_flags); |
61007b31 SH |
1772 | |
1773 | /* Keep bounce buffer around if it is big enough for all | |
1774 | * all future requests. | |
1775 | */ | |
5def6b80 | 1776 | if (num < max_transfer) { |
0d93ed08 VSO |
1777 | qemu_vfree(buf); |
1778 | buf = NULL; | |
61007b31 SH |
1779 | } |
1780 | } | |
1781 | ||
d05aa8bb | 1782 | offset += num; |
f5a5ca79 | 1783 | bytes -= num; |
61007b31 SH |
1784 | } |
1785 | ||
1786 | fail: | |
465fe887 EB |
1787 | if (ret == 0 && need_flush) { |
1788 | ret = bdrv_co_flush(bs); | |
1789 | } | |
0d93ed08 | 1790 | qemu_vfree(buf); |
61007b31 SH |
1791 | return ret; |
1792 | } | |
1793 | ||
85fe2479 | 1794 | static inline int coroutine_fn |
fcfd9ade | 1795 | bdrv_co_write_req_prepare(BdrvChild *child, int64_t offset, int64_t bytes, |
85fe2479 FZ |
1796 | BdrvTrackedRequest *req, int flags) |
1797 | { | |
1798 | BlockDriverState *bs = child->bs; | |
fcfd9ade VSO |
1799 | |
1800 | bdrv_check_request(offset, bytes, &error_abort); | |
85fe2479 | 1801 | |
307261b2 | 1802 | if (bdrv_is_read_only(bs)) { |
85fe2479 FZ |
1803 | return -EPERM; |
1804 | } | |
1805 | ||
85fe2479 FZ |
1806 | assert(!(bs->open_flags & BDRV_O_INACTIVE)); |
1807 | assert((bs->open_flags & BDRV_O_NO_IO) == 0); | |
1808 | assert(!(flags & ~BDRV_REQ_MASK)); | |
d1a764d1 | 1809 | assert(!((flags & BDRV_REQ_NO_WAIT) && !(flags & BDRV_REQ_SERIALISING))); |
85fe2479 FZ |
1810 | |
1811 | if (flags & BDRV_REQ_SERIALISING) { | |
d1a764d1 VSO |
1812 | QEMU_LOCK_GUARD(&bs->reqs_lock); |
1813 | ||
1814 | tracked_request_set_serialising(req, bdrv_get_cluster_size(bs)); | |
1815 | ||
1816 | if ((flags & BDRV_REQ_NO_WAIT) && bdrv_find_conflicting_request(req)) { | |
1817 | return -EBUSY; | |
1818 | } | |
1819 | ||
1820 | bdrv_wait_serialising_requests_locked(req); | |
18fbd0de PB |
1821 | } else { |
1822 | bdrv_wait_serialising_requests(req); | |
85fe2479 FZ |
1823 | } |
1824 | ||
85fe2479 FZ |
1825 | assert(req->overlap_offset <= offset); |
1826 | assert(offset + bytes <= req->overlap_offset + req->overlap_bytes); | |
fcfd9ade VSO |
1827 | assert(offset + bytes <= bs->total_sectors * BDRV_SECTOR_SIZE || |
1828 | child->perm & BLK_PERM_RESIZE); | |
85fe2479 | 1829 | |
cd47d792 FZ |
1830 | switch (req->type) { |
1831 | case BDRV_TRACKED_WRITE: | |
1832 | case BDRV_TRACKED_DISCARD: | |
1833 | if (flags & BDRV_REQ_WRITE_UNCHANGED) { | |
1834 | assert(child->perm & (BLK_PERM_WRITE_UNCHANGED | BLK_PERM_WRITE)); | |
1835 | } else { | |
1836 | assert(child->perm & BLK_PERM_WRITE); | |
1837 | } | |
94783301 VSO |
1838 | bdrv_write_threshold_check_write(bs, offset, bytes); |
1839 | return 0; | |
cd47d792 FZ |
1840 | case BDRV_TRACKED_TRUNCATE: |
1841 | assert(child->perm & BLK_PERM_RESIZE); | |
1842 | return 0; | |
1843 | default: | |
1844 | abort(); | |
85fe2479 | 1845 | } |
85fe2479 FZ |
1846 | } |
1847 | ||
1848 | static inline void coroutine_fn | |
fcfd9ade | 1849 | bdrv_co_write_req_finish(BdrvChild *child, int64_t offset, int64_t bytes, |
85fe2479 FZ |
1850 | BdrvTrackedRequest *req, int ret) |
1851 | { | |
1852 | int64_t end_sector = DIV_ROUND_UP(offset + bytes, BDRV_SECTOR_SIZE); | |
1853 | BlockDriverState *bs = child->bs; | |
1854 | ||
fcfd9ade VSO |
1855 | bdrv_check_request(offset, bytes, &error_abort); |
1856 | ||
d73415a3 | 1857 | qatomic_inc(&bs->write_gen); |
85fe2479 | 1858 | |
00695c27 FZ |
1859 | /* |
1860 | * Discard cannot extend the image, but in error handling cases, such as | |
1861 | * when reverting a qcow2 cluster allocation, the discarded range can pass | |
1862 | * the end of image file, so we cannot assert about BDRV_TRACKED_DISCARD | |
1863 | * here. Instead, just skip it, since semantically a discard request | |
1864 | * beyond EOF cannot expand the image anyway. | |
1865 | */ | |
7f8f03ef | 1866 | if (ret == 0 && |
cd47d792 FZ |
1867 | (req->type == BDRV_TRACKED_TRUNCATE || |
1868 | end_sector > bs->total_sectors) && | |
1869 | req->type != BDRV_TRACKED_DISCARD) { | |
7f8f03ef FZ |
1870 | bs->total_sectors = end_sector; |
1871 | bdrv_parent_cb_resize(bs); | |
1872 | bdrv_dirty_bitmap_truncate(bs, end_sector << BDRV_SECTOR_BITS); | |
85fe2479 | 1873 | } |
00695c27 FZ |
1874 | if (req->bytes) { |
1875 | switch (req->type) { | |
1876 | case BDRV_TRACKED_WRITE: | |
1877 | stat64_max(&bs->wr_highest_offset, offset + bytes); | |
1878 | /* fall through, to set dirty bits */ | |
1879 | case BDRV_TRACKED_DISCARD: | |
1880 | bdrv_set_dirty(bs, offset, bytes); | |
1881 | break; | |
1882 | default: | |
1883 | break; | |
1884 | } | |
1885 | } | |
85fe2479 FZ |
1886 | } |
1887 | ||
61007b31 | 1888 | /* |
04ed95f4 EB |
1889 | * Forwards an already correctly aligned write request to the BlockDriver, |
1890 | * after possibly fragmenting it. | |
61007b31 | 1891 | */ |
85c97ca7 | 1892 | static int coroutine_fn bdrv_aligned_pwritev(BdrvChild *child, |
fcfd9ade | 1893 | BdrvTrackedRequest *req, int64_t offset, int64_t bytes, |
e75abeda VSO |
1894 | int64_t align, QEMUIOVector *qiov, size_t qiov_offset, |
1895 | BdrvRequestFlags flags) | |
61007b31 | 1896 | { |
85c97ca7 | 1897 | BlockDriverState *bs = child->bs; |
61007b31 | 1898 | BlockDriver *drv = bs->drv; |
61007b31 SH |
1899 | int ret; |
1900 | ||
fcfd9ade | 1901 | int64_t bytes_remaining = bytes; |
04ed95f4 | 1902 | int max_transfer; |
61007b31 | 1903 | |
fcfd9ade VSO |
1904 | bdrv_check_qiov_request(offset, bytes, qiov, qiov_offset, &error_abort); |
1905 | ||
d470ad42 HR |
1906 | if (!drv) { |
1907 | return -ENOMEDIUM; | |
1908 | } | |
1909 | ||
d6883bc9 VSO |
1910 | if (bdrv_has_readonly_bitmaps(bs)) { |
1911 | return -EPERM; | |
1912 | } | |
1913 | ||
cff86b38 EB |
1914 | assert(is_power_of_2(align)); |
1915 | assert((offset & (align - 1)) == 0); | |
1916 | assert((bytes & (align - 1)) == 0); | |
04ed95f4 EB |
1917 | max_transfer = QEMU_ALIGN_DOWN(MIN_NON_ZERO(bs->bl.max_transfer, INT_MAX), |
1918 | align); | |
61007b31 | 1919 | |
85fe2479 | 1920 | ret = bdrv_co_write_req_prepare(child, offset, bytes, req, flags); |
61007b31 SH |
1921 | |
1922 | if (!ret && bs->detect_zeroes != BLOCKDEV_DETECT_ZEROES_OPTIONS_OFF && | |
c1499a5e | 1923 | !(flags & BDRV_REQ_ZERO_WRITE) && drv->bdrv_co_pwrite_zeroes && |
28c4da28 | 1924 | qemu_iovec_is_zero(qiov, qiov_offset, bytes)) { |
61007b31 SH |
1925 | flags |= BDRV_REQ_ZERO_WRITE; |
1926 | if (bs->detect_zeroes == BLOCKDEV_DETECT_ZEROES_OPTIONS_UNMAP) { | |
1927 | flags |= BDRV_REQ_MAY_UNMAP; | |
1928 | } | |
1929 | } | |
1930 | ||
1931 | if (ret < 0) { | |
1932 | /* Do nothing, write notifier decided to fail this request */ | |
1933 | } else if (flags & BDRV_REQ_ZERO_WRITE) { | |
9a4f4c31 | 1934 | bdrv_debug_event(bs, BLKDBG_PWRITEV_ZERO); |
9896c876 | 1935 | ret = bdrv_co_do_pwrite_zeroes(bs, offset, bytes, flags); |
3ea1a091 | 1936 | } else if (flags & BDRV_REQ_WRITE_COMPRESSED) { |
28c4da28 VSO |
1937 | ret = bdrv_driver_pwritev_compressed(bs, offset, bytes, |
1938 | qiov, qiov_offset); | |
04ed95f4 | 1939 | } else if (bytes <= max_transfer) { |
9a4f4c31 | 1940 | bdrv_debug_event(bs, BLKDBG_PWRITEV); |
28c4da28 | 1941 | ret = bdrv_driver_pwritev(bs, offset, bytes, qiov, qiov_offset, flags); |
04ed95f4 EB |
1942 | } else { |
1943 | bdrv_debug_event(bs, BLKDBG_PWRITEV); | |
1944 | while (bytes_remaining) { | |
1945 | int num = MIN(bytes_remaining, max_transfer); | |
04ed95f4 EB |
1946 | int local_flags = flags; |
1947 | ||
1948 | assert(num); | |
1949 | if (num < bytes_remaining && (flags & BDRV_REQ_FUA) && | |
1950 | !(bs->supported_write_flags & BDRV_REQ_FUA)) { | |
1951 | /* If FUA is going to be emulated by flush, we only | |
1952 | * need to flush on the last iteration */ | |
1953 | local_flags &= ~BDRV_REQ_FUA; | |
1954 | } | |
04ed95f4 EB |
1955 | |
1956 | ret = bdrv_driver_pwritev(bs, offset + bytes - bytes_remaining, | |
134b7dec HR |
1957 | num, qiov, |
1958 | qiov_offset + bytes - bytes_remaining, | |
28c4da28 | 1959 | local_flags); |
04ed95f4 EB |
1960 | if (ret < 0) { |
1961 | break; | |
1962 | } | |
1963 | bytes_remaining -= num; | |
1964 | } | |
61007b31 | 1965 | } |
9a4f4c31 | 1966 | bdrv_debug_event(bs, BLKDBG_PWRITEV_DONE); |
61007b31 | 1967 | |
61007b31 | 1968 | if (ret >= 0) { |
04ed95f4 | 1969 | ret = 0; |
61007b31 | 1970 | } |
85fe2479 | 1971 | bdrv_co_write_req_finish(child, offset, bytes, req, ret); |
61007b31 SH |
1972 | |
1973 | return ret; | |
1974 | } | |
1975 | ||
85c97ca7 | 1976 | static int coroutine_fn bdrv_co_do_zero_pwritev(BdrvChild *child, |
9eeb6dd1 | 1977 | int64_t offset, |
37e9403e | 1978 | int64_t bytes, |
9eeb6dd1 FZ |
1979 | BdrvRequestFlags flags, |
1980 | BdrvTrackedRequest *req) | |
1981 | { | |
85c97ca7 | 1982 | BlockDriverState *bs = child->bs; |
9eeb6dd1 | 1983 | QEMUIOVector local_qiov; |
a5b8dd2c | 1984 | uint64_t align = bs->bl.request_alignment; |
9eeb6dd1 | 1985 | int ret = 0; |
7a3f542f VSO |
1986 | bool padding; |
1987 | BdrvRequestPadding pad; | |
9eeb6dd1 | 1988 | |
e8b65355 SH |
1989 | /* This flag doesn't make sense for padding or zero writes */ |
1990 | flags &= ~BDRV_REQ_REGISTERED_BUF; | |
1991 | ||
7a3f542f VSO |
1992 | padding = bdrv_init_padding(bs, offset, bytes, &pad); |
1993 | if (padding) { | |
45e62b46 | 1994 | assert(!(flags & BDRV_REQ_NO_WAIT)); |
8ac5aab2 | 1995 | bdrv_make_request_serialising(req, align); |
9eeb6dd1 | 1996 | |
7a3f542f VSO |
1997 | bdrv_padding_rmw_read(child, req, &pad, true); |
1998 | ||
1999 | if (pad.head || pad.merge_reads) { | |
2000 | int64_t aligned_offset = offset & ~(align - 1); | |
2001 | int64_t write_bytes = pad.merge_reads ? pad.buf_len : align; | |
2002 | ||
2003 | qemu_iovec_init_buf(&local_qiov, pad.buf, write_bytes); | |
2004 | ret = bdrv_aligned_pwritev(child, req, aligned_offset, write_bytes, | |
28c4da28 | 2005 | align, &local_qiov, 0, |
7a3f542f VSO |
2006 | flags & ~BDRV_REQ_ZERO_WRITE); |
2007 | if (ret < 0 || pad.merge_reads) { | |
2008 | /* Error or all work is done */ | |
2009 | goto out; | |
2010 | } | |
2011 | offset += write_bytes - pad.head; | |
2012 | bytes -= write_bytes - pad.head; | |
9eeb6dd1 | 2013 | } |
9eeb6dd1 FZ |
2014 | } |
2015 | ||
2016 | assert(!bytes || (offset & (align - 1)) == 0); | |
2017 | if (bytes >= align) { | |
2018 | /* Write the aligned part in the middle. */ | |
fcfd9ade | 2019 | int64_t aligned_bytes = bytes & ~(align - 1); |
85c97ca7 | 2020 | ret = bdrv_aligned_pwritev(child, req, offset, aligned_bytes, align, |
28c4da28 | 2021 | NULL, 0, flags); |
9eeb6dd1 | 2022 | if (ret < 0) { |
7a3f542f | 2023 | goto out; |
9eeb6dd1 FZ |
2024 | } |
2025 | bytes -= aligned_bytes; | |
2026 | offset += aligned_bytes; | |
2027 | } | |
2028 | ||
2029 | assert(!bytes || (offset & (align - 1)) == 0); | |
2030 | if (bytes) { | |
7a3f542f | 2031 | assert(align == pad.tail + bytes); |
9eeb6dd1 | 2032 | |
7a3f542f | 2033 | qemu_iovec_init_buf(&local_qiov, pad.tail_buf, align); |
85c97ca7 | 2034 | ret = bdrv_aligned_pwritev(child, req, offset, align, align, |
28c4da28 VSO |
2035 | &local_qiov, 0, |
2036 | flags & ~BDRV_REQ_ZERO_WRITE); | |
9eeb6dd1 | 2037 | } |
9eeb6dd1 | 2038 | |
7a3f542f VSO |
2039 | out: |
2040 | bdrv_padding_destroy(&pad); | |
2041 | ||
2042 | return ret; | |
9eeb6dd1 FZ |
2043 | } |
2044 | ||
61007b31 SH |
2045 | /* |
2046 | * Handle a write request in coroutine context | |
2047 | */ | |
a03ef88f | 2048 | int coroutine_fn bdrv_co_pwritev(BdrvChild *child, |
e9e52efd | 2049 | int64_t offset, int64_t bytes, QEMUIOVector *qiov, |
61007b31 | 2050 | BdrvRequestFlags flags) |
1acc3466 | 2051 | { |
967d7905 | 2052 | IO_CODE(); |
1acc3466 VSO |
2053 | return bdrv_co_pwritev_part(child, offset, bytes, qiov, 0, flags); |
2054 | } | |
2055 | ||
2056 | int coroutine_fn bdrv_co_pwritev_part(BdrvChild *child, | |
37e9403e | 2057 | int64_t offset, int64_t bytes, QEMUIOVector *qiov, size_t qiov_offset, |
1acc3466 | 2058 | BdrvRequestFlags flags) |
61007b31 | 2059 | { |
a03ef88f | 2060 | BlockDriverState *bs = child->bs; |
61007b31 | 2061 | BdrvTrackedRequest req; |
a5b8dd2c | 2062 | uint64_t align = bs->bl.request_alignment; |
7a3f542f | 2063 | BdrvRequestPadding pad; |
61007b31 | 2064 | int ret; |
f0deecff | 2065 | bool padded = false; |
967d7905 | 2066 | IO_CODE(); |
61007b31 | 2067 | |
37e9403e | 2068 | trace_bdrv_co_pwritev_part(child->bs, offset, bytes, flags); |
f42cf447 | 2069 | |
1e97be91 | 2070 | if (!bdrv_co_is_inserted(bs)) { |
61007b31 SH |
2071 | return -ENOMEDIUM; |
2072 | } | |
61007b31 | 2073 | |
2aaa3f9b VSO |
2074 | if (flags & BDRV_REQ_ZERO_WRITE) { |
2075 | ret = bdrv_check_qiov_request(offset, bytes, qiov, qiov_offset, NULL); | |
2076 | } else { | |
2077 | ret = bdrv_check_request32(offset, bytes, qiov, qiov_offset); | |
2078 | } | |
61007b31 SH |
2079 | if (ret < 0) { |
2080 | return ret; | |
2081 | } | |
2082 | ||
f2208fdc AG |
2083 | /* If the request is misaligned then we can't make it efficient */ |
2084 | if ((flags & BDRV_REQ_NO_FALLBACK) && | |
2085 | !QEMU_IS_ALIGNED(offset | bytes, align)) | |
2086 | { | |
2087 | return -ENOTSUP; | |
2088 | } | |
2089 | ||
ac9d00bf VSO |
2090 | if (bytes == 0 && !QEMU_IS_ALIGNED(offset, bs->bl.request_alignment)) { |
2091 | /* | |
2092 | * Aligning zero request is nonsense. Even if driver has special meaning | |
2093 | * of zero-length (like qcow2_co_pwritev_compressed_part), we can't pass | |
2094 | * it to driver due to request_alignment. | |
2095 | * | |
2096 | * Still, no reason to return an error if someone do unaligned | |
2097 | * zero-length write occasionally. | |
2098 | */ | |
2099 | return 0; | |
2100 | } | |
2101 | ||
f0deecff VSO |
2102 | if (!(flags & BDRV_REQ_ZERO_WRITE)) { |
2103 | /* | |
2104 | * Pad request for following read-modify-write cycle. | |
2105 | * bdrv_co_do_zero_pwritev() does aligning by itself, so, we do | |
2106 | * alignment only if there is no ZERO flag. | |
2107 | */ | |
98ca4549 | 2108 | ret = bdrv_pad_request(bs, &qiov, &qiov_offset, &offset, &bytes, &pad, |
e8b65355 | 2109 | &padded, &flags); |
98ca4549 VSO |
2110 | if (ret < 0) { |
2111 | return ret; | |
2112 | } | |
f0deecff VSO |
2113 | } |
2114 | ||
99723548 | 2115 | bdrv_inc_in_flight(bs); |
ebde595c | 2116 | tracked_request_begin(&req, bs, offset, bytes, BDRV_TRACKED_WRITE); |
61007b31 | 2117 | |
18a59f03 | 2118 | if (flags & BDRV_REQ_ZERO_WRITE) { |
f0deecff | 2119 | assert(!padded); |
85c97ca7 | 2120 | ret = bdrv_co_do_zero_pwritev(child, offset, bytes, flags, &req); |
9eeb6dd1 FZ |
2121 | goto out; |
2122 | } | |
2123 | ||
f0deecff VSO |
2124 | if (padded) { |
2125 | /* | |
2126 | * Request was unaligned to request_alignment and therefore | |
2127 | * padded. We are going to do read-modify-write, and must | |
2128 | * serialize the request to prevent interactions of the | |
2129 | * widened region with other transactions. | |
2130 | */ | |
45e62b46 | 2131 | assert(!(flags & BDRV_REQ_NO_WAIT)); |
8ac5aab2 | 2132 | bdrv_make_request_serialising(&req, align); |
7a3f542f | 2133 | bdrv_padding_rmw_read(child, &req, &pad, false); |
61007b31 SH |
2134 | } |
2135 | ||
85c97ca7 | 2136 | ret = bdrv_aligned_pwritev(child, &req, offset, bytes, align, |
1acc3466 | 2137 | qiov, qiov_offset, flags); |
61007b31 | 2138 | |
7a3f542f | 2139 | bdrv_padding_destroy(&pad); |
61007b31 | 2140 | |
9eeb6dd1 FZ |
2141 | out: |
2142 | tracked_request_end(&req); | |
99723548 | 2143 | bdrv_dec_in_flight(bs); |
7a3f542f | 2144 | |
61007b31 SH |
2145 | return ret; |
2146 | } | |
2147 | ||
a03ef88f | 2148 | int coroutine_fn bdrv_co_pwrite_zeroes(BdrvChild *child, int64_t offset, |
e9e52efd | 2149 | int64_t bytes, BdrvRequestFlags flags) |
61007b31 | 2150 | { |
384a48fb | 2151 | IO_CODE(); |
f5a5ca79 | 2152 | trace_bdrv_co_pwrite_zeroes(child->bs, offset, bytes, flags); |
61007b31 | 2153 | |
a03ef88f | 2154 | if (!(child->bs->open_flags & BDRV_O_UNMAP)) { |
61007b31 SH |
2155 | flags &= ~BDRV_REQ_MAY_UNMAP; |
2156 | } | |
61007b31 | 2157 | |
f5a5ca79 | 2158 | return bdrv_co_pwritev(child, offset, bytes, NULL, |
74021bc4 | 2159 | BDRV_REQ_ZERO_WRITE | flags); |
61007b31 SH |
2160 | } |
2161 | ||
4085f5c7 JS |
2162 | /* |
2163 | * Flush ALL BDSes regardless of if they are reachable via a BlkBackend or not. | |
2164 | */ | |
2165 | int bdrv_flush_all(void) | |
2166 | { | |
2167 | BdrvNextIterator it; | |
2168 | BlockDriverState *bs = NULL; | |
2169 | int result = 0; | |
2170 | ||
f791bf7f EGE |
2171 | GLOBAL_STATE_CODE(); |
2172 | ||
c8aa7895 PD |
2173 | /* |
2174 | * bdrv queue is managed by record/replay, | |
2175 | * creating new flush request for stopping | |
2176 | * the VM may break the determinism | |
2177 | */ | |
2178 | if (replay_events_enabled()) { | |
2179 | return result; | |
2180 | } | |
2181 | ||
4085f5c7 JS |
2182 | for (bs = bdrv_first(&it); bs; bs = bdrv_next(&it)) { |
2183 | AioContext *aio_context = bdrv_get_aio_context(bs); | |
2184 | int ret; | |
2185 | ||
2186 | aio_context_acquire(aio_context); | |
2187 | ret = bdrv_flush(bs); | |
2188 | if (ret < 0 && !result) { | |
2189 | result = ret; | |
2190 | } | |
2191 | aio_context_release(aio_context); | |
2192 | } | |
2193 | ||
2194 | return result; | |
2195 | } | |
2196 | ||
61007b31 SH |
2197 | /* |
2198 | * Returns the allocation status of the specified sectors. | |
2199 | * Drivers not implementing the functionality are assumed to not support | |
2200 | * backing files, hence all their sectors are reported as allocated. | |
2201 | * | |
86a3d5c6 EB |
2202 | * If 'want_zero' is true, the caller is querying for mapping |
2203 | * purposes, with a focus on valid BDRV_BLOCK_OFFSET_VALID, _DATA, and | |
2204 | * _ZERO where possible; otherwise, the result favors larger 'pnum', | |
2205 | * with a focus on accurate BDRV_BLOCK_ALLOCATED. | |
c9ce8c4d | 2206 | * |
2e8bc787 | 2207 | * If 'offset' is beyond the end of the disk image the return value is |
fb0d8654 | 2208 | * BDRV_BLOCK_EOF and 'pnum' is set to 0. |
61007b31 | 2209 | * |
2e8bc787 | 2210 | * 'bytes' is the max value 'pnum' should be set to. If bytes goes |
fb0d8654 EB |
2211 | * beyond the end of the disk image it will be clamped; if 'pnum' is set to |
2212 | * the end of the image, then the returned value will include BDRV_BLOCK_EOF. | |
67a0fd2a | 2213 | * |
2e8bc787 EB |
2214 | * 'pnum' is set to the number of bytes (including and immediately |
2215 | * following the specified offset) that are easily known to be in the | |
2216 | * same allocated/unallocated state. Note that a second call starting | |
2217 | * at the original offset plus returned pnum may have the same status. | |
2218 | * The returned value is non-zero on success except at end-of-file. | |
2219 | * | |
2220 | * Returns negative errno on failure. Otherwise, if the | |
2221 | * BDRV_BLOCK_OFFSET_VALID bit is set, 'map' and 'file' (if non-NULL) are | |
2222 | * set to the host mapping and BDS corresponding to the guest offset. | |
61007b31 | 2223 | */ |
2e8bc787 EB |
2224 | static int coroutine_fn bdrv_co_block_status(BlockDriverState *bs, |
2225 | bool want_zero, | |
2226 | int64_t offset, int64_t bytes, | |
2227 | int64_t *pnum, int64_t *map, | |
2228 | BlockDriverState **file) | |
2229 | { | |
2230 | int64_t total_size; | |
2231 | int64_t n; /* bytes */ | |
efa6e2ed | 2232 | int ret; |
2e8bc787 | 2233 | int64_t local_map = 0; |
298a1665 | 2234 | BlockDriverState *local_file = NULL; |
efa6e2ed EB |
2235 | int64_t aligned_offset, aligned_bytes; |
2236 | uint32_t align; | |
549ec0d9 | 2237 | bool has_filtered_child; |
61007b31 | 2238 | |
298a1665 EB |
2239 | assert(pnum); |
2240 | *pnum = 0; | |
2e8bc787 EB |
2241 | total_size = bdrv_getlength(bs); |
2242 | if (total_size < 0) { | |
2243 | ret = total_size; | |
298a1665 | 2244 | goto early_out; |
61007b31 SH |
2245 | } |
2246 | ||
2e8bc787 | 2247 | if (offset >= total_size) { |
298a1665 EB |
2248 | ret = BDRV_BLOCK_EOF; |
2249 | goto early_out; | |
61007b31 | 2250 | } |
2e8bc787 | 2251 | if (!bytes) { |
298a1665 EB |
2252 | ret = 0; |
2253 | goto early_out; | |
9cdcfd9f | 2254 | } |
61007b31 | 2255 | |
2e8bc787 EB |
2256 | n = total_size - offset; |
2257 | if (n < bytes) { | |
2258 | bytes = n; | |
61007b31 SH |
2259 | } |
2260 | ||
d470ad42 HR |
2261 | /* Must be non-NULL or bdrv_getlength() would have failed */ |
2262 | assert(bs->drv); | |
549ec0d9 HR |
2263 | has_filtered_child = bdrv_filter_child(bs); |
2264 | if (!bs->drv->bdrv_co_block_status && !has_filtered_child) { | |
2e8bc787 | 2265 | *pnum = bytes; |
61007b31 | 2266 | ret = BDRV_BLOCK_DATA | BDRV_BLOCK_ALLOCATED; |
2e8bc787 | 2267 | if (offset + bytes == total_size) { |
fb0d8654 EB |
2268 | ret |= BDRV_BLOCK_EOF; |
2269 | } | |
61007b31 | 2270 | if (bs->drv->protocol_name) { |
2e8bc787 EB |
2271 | ret |= BDRV_BLOCK_OFFSET_VALID; |
2272 | local_map = offset; | |
298a1665 | 2273 | local_file = bs; |
61007b31 | 2274 | } |
298a1665 | 2275 | goto early_out; |
61007b31 SH |
2276 | } |
2277 | ||
99723548 | 2278 | bdrv_inc_in_flight(bs); |
efa6e2ed EB |
2279 | |
2280 | /* Round out to request_alignment boundaries */ | |
86a3d5c6 | 2281 | align = bs->bl.request_alignment; |
efa6e2ed EB |
2282 | aligned_offset = QEMU_ALIGN_DOWN(offset, align); |
2283 | aligned_bytes = ROUND_UP(offset + bytes, align) - aligned_offset; | |
2284 | ||
549ec0d9 | 2285 | if (bs->drv->bdrv_co_block_status) { |
0bc329fb HR |
2286 | /* |
2287 | * Use the block-status cache only for protocol nodes: Format | |
2288 | * drivers are generally quick to inquire the status, but protocol | |
2289 | * drivers often need to get information from outside of qemu, so | |
2290 | * we do not have control over the actual implementation. There | |
2291 | * have been cases where inquiring the status took an unreasonably | |
2292 | * long time, and we can do nothing in qemu to fix it. | |
2293 | * This is especially problematic for images with large data areas, | |
2294 | * because finding the few holes in them and giving them special | |
2295 | * treatment does not gain much performance. Therefore, we try to | |
2296 | * cache the last-identified data region. | |
2297 | * | |
2298 | * Second, limiting ourselves to protocol nodes allows us to assume | |
2299 | * the block status for data regions to be DATA | OFFSET_VALID, and | |
2300 | * that the host offset is the same as the guest offset. | |
2301 | * | |
2302 | * Note that it is possible that external writers zero parts of | |
2303 | * the cached regions without the cache being invalidated, and so | |
2304 | * we may report zeroes as data. This is not catastrophic, | |
2305 | * however, because reporting zeroes as data is fine. | |
2306 | */ | |
2307 | if (QLIST_EMPTY(&bs->children) && | |
2308 | bdrv_bsc_is_data(bs, aligned_offset, pnum)) | |
2309 | { | |
2310 | ret = BDRV_BLOCK_DATA | BDRV_BLOCK_OFFSET_VALID; | |
2311 | local_file = bs; | |
2312 | local_map = aligned_offset; | |
2313 | } else { | |
2314 | ret = bs->drv->bdrv_co_block_status(bs, want_zero, aligned_offset, | |
2315 | aligned_bytes, pnum, &local_map, | |
2316 | &local_file); | |
2317 | ||
2318 | /* | |
2319 | * Note that checking QLIST_EMPTY(&bs->children) is also done when | |
2320 | * the cache is queried above. Technically, we do not need to check | |
2321 | * it here; the worst that can happen is that we fill the cache for | |
2322 | * non-protocol nodes, and then it is never used. However, filling | |
2323 | * the cache requires an RCU update, so double check here to avoid | |
2324 | * such an update if possible. | |
113b727c HR |
2325 | * |
2326 | * Check want_zero, because we only want to update the cache when we | |
2327 | * have accurate information about what is zero and what is data. | |
0bc329fb | 2328 | */ |
113b727c HR |
2329 | if (want_zero && |
2330 | ret == (BDRV_BLOCK_DATA | BDRV_BLOCK_OFFSET_VALID) && | |
0bc329fb HR |
2331 | QLIST_EMPTY(&bs->children)) |
2332 | { | |
2333 | /* | |
2334 | * When a protocol driver reports BLOCK_OFFSET_VALID, the | |
2335 | * returned local_map value must be the same as the offset we | |
2336 | * have passed (aligned_offset), and local_bs must be the node | |
2337 | * itself. | |
2338 | * Assert this, because we follow this rule when reading from | |
2339 | * the cache (see the `local_file = bs` and | |
2340 | * `local_map = aligned_offset` assignments above), and the | |
2341 | * result the cache delivers must be the same as the driver | |
2342 | * would deliver. | |
2343 | */ | |
2344 | assert(local_file == bs); | |
2345 | assert(local_map == aligned_offset); | |
2346 | bdrv_bsc_fill(bs, aligned_offset, *pnum); | |
2347 | } | |
2348 | } | |
549ec0d9 HR |
2349 | } else { |
2350 | /* Default code for filters */ | |
2351 | ||
2352 | local_file = bdrv_filter_bs(bs); | |
2353 | assert(local_file); | |
2354 | ||
2355 | *pnum = aligned_bytes; | |
2356 | local_map = aligned_offset; | |
2357 | ret = BDRV_BLOCK_RAW | BDRV_BLOCK_OFFSET_VALID; | |
2358 | } | |
636cb512 EB |
2359 | if (ret < 0) { |
2360 | *pnum = 0; | |
2361 | goto out; | |
efa6e2ed EB |
2362 | } |
2363 | ||
2e8bc787 | 2364 | /* |
636cb512 | 2365 | * The driver's result must be a non-zero multiple of request_alignment. |
efa6e2ed | 2366 | * Clamp pnum and adjust map to original request. |
2e8bc787 | 2367 | */ |
636cb512 EB |
2368 | assert(*pnum && QEMU_IS_ALIGNED(*pnum, align) && |
2369 | align > offset - aligned_offset); | |
69f47505 VSO |
2370 | if (ret & BDRV_BLOCK_RECURSE) { |
2371 | assert(ret & BDRV_BLOCK_DATA); | |
2372 | assert(ret & BDRV_BLOCK_OFFSET_VALID); | |
2373 | assert(!(ret & BDRV_BLOCK_ZERO)); | |
2374 | } | |
2375 | ||
efa6e2ed EB |
2376 | *pnum -= offset - aligned_offset; |
2377 | if (*pnum > bytes) { | |
2378 | *pnum = bytes; | |
61007b31 | 2379 | } |
2e8bc787 | 2380 | if (ret & BDRV_BLOCK_OFFSET_VALID) { |
efa6e2ed | 2381 | local_map += offset - aligned_offset; |
2e8bc787 | 2382 | } |
61007b31 SH |
2383 | |
2384 | if (ret & BDRV_BLOCK_RAW) { | |
298a1665 | 2385 | assert(ret & BDRV_BLOCK_OFFSET_VALID && local_file); |
2e8bc787 EB |
2386 | ret = bdrv_co_block_status(local_file, want_zero, local_map, |
2387 | *pnum, pnum, &local_map, &local_file); | |
99723548 | 2388 | goto out; |
61007b31 SH |
2389 | } |
2390 | ||
2391 | if (ret & (BDRV_BLOCK_DATA | BDRV_BLOCK_ZERO)) { | |
2392 | ret |= BDRV_BLOCK_ALLOCATED; | |
d40f4a56 | 2393 | } else if (bs->drv->supports_backing) { |
cb850315 HR |
2394 | BlockDriverState *cow_bs = bdrv_cow_bs(bs); |
2395 | ||
d40f4a56 AG |
2396 | if (!cow_bs) { |
2397 | ret |= BDRV_BLOCK_ZERO; | |
2398 | } else if (want_zero) { | |
cb850315 | 2399 | int64_t size2 = bdrv_getlength(cow_bs); |
c9ce8c4d | 2400 | |
2e8bc787 | 2401 | if (size2 >= 0 && offset >= size2) { |
61007b31 SH |
2402 | ret |= BDRV_BLOCK_ZERO; |
2403 | } | |
2404 | } | |
2405 | } | |
2406 | ||
69f47505 VSO |
2407 | if (want_zero && ret & BDRV_BLOCK_RECURSE && |
2408 | local_file && local_file != bs && | |
61007b31 SH |
2409 | (ret & BDRV_BLOCK_DATA) && !(ret & BDRV_BLOCK_ZERO) && |
2410 | (ret & BDRV_BLOCK_OFFSET_VALID)) { | |
2e8bc787 EB |
2411 | int64_t file_pnum; |
2412 | int ret2; | |
61007b31 | 2413 | |
2e8bc787 EB |
2414 | ret2 = bdrv_co_block_status(local_file, want_zero, local_map, |
2415 | *pnum, &file_pnum, NULL, NULL); | |
61007b31 SH |
2416 | if (ret2 >= 0) { |
2417 | /* Ignore errors. This is just providing extra information, it | |
2418 | * is useful but not necessary. | |
2419 | */ | |
c61e684e EB |
2420 | if (ret2 & BDRV_BLOCK_EOF && |
2421 | (!file_pnum || ret2 & BDRV_BLOCK_ZERO)) { | |
2422 | /* | |
2423 | * It is valid for the format block driver to read | |
2424 | * beyond the end of the underlying file's current | |
2425 | * size; such areas read as zero. | |
2426 | */ | |
61007b31 SH |
2427 | ret |= BDRV_BLOCK_ZERO; |
2428 | } else { | |
2429 | /* Limit request to the range reported by the protocol driver */ | |
2430 | *pnum = file_pnum; | |
2431 | ret |= (ret2 & BDRV_BLOCK_ZERO); | |
2432 | } | |
2433 | } | |
2434 | } | |
2435 | ||
99723548 PB |
2436 | out: |
2437 | bdrv_dec_in_flight(bs); | |
2e8bc787 | 2438 | if (ret >= 0 && offset + *pnum == total_size) { |
fb0d8654 EB |
2439 | ret |= BDRV_BLOCK_EOF; |
2440 | } | |
298a1665 EB |
2441 | early_out: |
2442 | if (file) { | |
2443 | *file = local_file; | |
2444 | } | |
2e8bc787 EB |
2445 | if (map) { |
2446 | *map = local_map; | |
2447 | } | |
61007b31 SH |
2448 | return ret; |
2449 | } | |
2450 | ||
21c2283e | 2451 | int coroutine_fn |
f9e694cb VSO |
2452 | bdrv_co_common_block_status_above(BlockDriverState *bs, |
2453 | BlockDriverState *base, | |
3555a432 | 2454 | bool include_base, |
f9e694cb VSO |
2455 | bool want_zero, |
2456 | int64_t offset, | |
2457 | int64_t bytes, | |
2458 | int64_t *pnum, | |
2459 | int64_t *map, | |
a92b1b06 EB |
2460 | BlockDriverState **file, |
2461 | int *depth) | |
ba3f0e25 | 2462 | { |
67c095c8 | 2463 | int ret; |
ba3f0e25 | 2464 | BlockDriverState *p; |
67c095c8 | 2465 | int64_t eof = 0; |
a92b1b06 | 2466 | int dummy; |
1581a70d | 2467 | IO_CODE(); |
ba3f0e25 | 2468 | |
3555a432 | 2469 | assert(!include_base || base); /* Can't include NULL base */ |
67c095c8 | 2470 | |
a92b1b06 EB |
2471 | if (!depth) { |
2472 | depth = &dummy; | |
2473 | } | |
2474 | *depth = 0; | |
2475 | ||
624f27bb VSO |
2476 | if (!include_base && bs == base) { |
2477 | *pnum = bytes; | |
2478 | return 0; | |
2479 | } | |
2480 | ||
67c095c8 | 2481 | ret = bdrv_co_block_status(bs, want_zero, offset, bytes, pnum, map, file); |
a92b1b06 | 2482 | ++*depth; |
3555a432 | 2483 | if (ret < 0 || *pnum == 0 || ret & BDRV_BLOCK_ALLOCATED || bs == base) { |
67c095c8 VSO |
2484 | return ret; |
2485 | } | |
2486 | ||
2487 | if (ret & BDRV_BLOCK_EOF) { | |
2488 | eof = offset + *pnum; | |
2489 | } | |
2490 | ||
2491 | assert(*pnum <= bytes); | |
2492 | bytes = *pnum; | |
2493 | ||
3555a432 | 2494 | for (p = bdrv_filter_or_cow_bs(bs); include_base || p != base; |
67c095c8 VSO |
2495 | p = bdrv_filter_or_cow_bs(p)) |
2496 | { | |
5b648c67 EB |
2497 | ret = bdrv_co_block_status(p, want_zero, offset, bytes, pnum, map, |
2498 | file); | |
a92b1b06 | 2499 | ++*depth; |
c61e684e | 2500 | if (ret < 0) { |
67c095c8 | 2501 | return ret; |
c61e684e | 2502 | } |
67c095c8 | 2503 | if (*pnum == 0) { |
c61e684e | 2504 | /* |
67c095c8 VSO |
2505 | * The top layer deferred to this layer, and because this layer is |
2506 | * short, any zeroes that we synthesize beyond EOF behave as if they | |
2507 | * were allocated at this layer. | |
2508 | * | |
2509 | * We don't include BDRV_BLOCK_EOF into ret, as upper layer may be | |
2510 | * larger. We'll add BDRV_BLOCK_EOF if needed at function end, see | |
2511 | * below. | |
c61e684e | 2512 | */ |
67c095c8 | 2513 | assert(ret & BDRV_BLOCK_EOF); |
5b648c67 | 2514 | *pnum = bytes; |
67c095c8 VSO |
2515 | if (file) { |
2516 | *file = p; | |
2517 | } | |
2518 | ret = BDRV_BLOCK_ZERO | BDRV_BLOCK_ALLOCATED; | |
2519 | break; | |
c61e684e | 2520 | } |
67c095c8 VSO |
2521 | if (ret & BDRV_BLOCK_ALLOCATED) { |
2522 | /* | |
2523 | * We've found the node and the status, we must break. | |
2524 | * | |
2525 | * Drop BDRV_BLOCK_EOF, as it's not for upper layer, which may be | |
2526 | * larger. We'll add BDRV_BLOCK_EOF if needed at function end, see | |
2527 | * below. | |
2528 | */ | |
2529 | ret &= ~BDRV_BLOCK_EOF; | |
ba3f0e25 FZ |
2530 | break; |
2531 | } | |
67c095c8 | 2532 | |
3555a432 VSO |
2533 | if (p == base) { |
2534 | assert(include_base); | |
2535 | break; | |
2536 | } | |
2537 | ||
67c095c8 VSO |
2538 | /* |
2539 | * OK, [offset, offset + *pnum) region is unallocated on this layer, | |
2540 | * let's continue the diving. | |
2541 | */ | |
2542 | assert(*pnum <= bytes); | |
2543 | bytes = *pnum; | |
ba3f0e25 | 2544 | } |
67c095c8 VSO |
2545 | |
2546 | if (offset + *pnum == eof) { | |
2547 | ret |= BDRV_BLOCK_EOF; | |
2548 | } | |
2549 | ||
ba3f0e25 FZ |
2550 | return ret; |
2551 | } | |
2552 | ||
7b52a921 EGE |
2553 | int coroutine_fn bdrv_co_block_status_above(BlockDriverState *bs, |
2554 | BlockDriverState *base, | |
2555 | int64_t offset, int64_t bytes, | |
2556 | int64_t *pnum, int64_t *map, | |
2557 | BlockDriverState **file) | |
2558 | { | |
2559 | IO_CODE(); | |
2560 | return bdrv_co_common_block_status_above(bs, base, false, true, offset, | |
2561 | bytes, pnum, map, file, NULL); | |
2562 | } | |
2563 | ||
31826642 EB |
2564 | int bdrv_block_status_above(BlockDriverState *bs, BlockDriverState *base, |
2565 | int64_t offset, int64_t bytes, int64_t *pnum, | |
2566 | int64_t *map, BlockDriverState **file) | |
c9ce8c4d | 2567 | { |
384a48fb | 2568 | IO_CODE(); |
3555a432 | 2569 | return bdrv_common_block_status_above(bs, base, false, true, offset, bytes, |
a92b1b06 | 2570 | pnum, map, file, NULL); |
c9ce8c4d EB |
2571 | } |
2572 | ||
237d78f8 EB |
2573 | int bdrv_block_status(BlockDriverState *bs, int64_t offset, int64_t bytes, |
2574 | int64_t *pnum, int64_t *map, BlockDriverState **file) | |
ba3f0e25 | 2575 | { |
384a48fb | 2576 | IO_CODE(); |
cb850315 | 2577 | return bdrv_block_status_above(bs, bdrv_filter_or_cow_bs(bs), |
31826642 | 2578 | offset, bytes, pnum, map, file); |
ba3f0e25 FZ |
2579 | } |
2580 | ||
46cd1e8a AG |
2581 | /* |
2582 | * Check @bs (and its backing chain) to see if the range defined | |
2583 | * by @offset and @bytes is known to read as zeroes. | |
2584 | * Return 1 if that is the case, 0 otherwise and -errno on error. | |
2585 | * This test is meant to be fast rather than accurate so returning 0 | |
2586 | * does not guarantee non-zero data. | |
2587 | */ | |
2588 | int coroutine_fn bdrv_co_is_zero_fast(BlockDriverState *bs, int64_t offset, | |
2589 | int64_t bytes) | |
2590 | { | |
2591 | int ret; | |
2592 | int64_t pnum = bytes; | |
384a48fb | 2593 | IO_CODE(); |
46cd1e8a AG |
2594 | |
2595 | if (!bytes) { | |
2596 | return 1; | |
2597 | } | |
2598 | ||
ce47ff20 AF |
2599 | ret = bdrv_co_common_block_status_above(bs, NULL, false, false, offset, |
2600 | bytes, &pnum, NULL, NULL, NULL); | |
46cd1e8a AG |
2601 | |
2602 | if (ret < 0) { | |
2603 | return ret; | |
2604 | } | |
2605 | ||
2606 | return (pnum == bytes) && (ret & BDRV_BLOCK_ZERO); | |
2607 | } | |
2608 | ||
7b52a921 EGE |
2609 | int coroutine_fn bdrv_co_is_allocated(BlockDriverState *bs, int64_t offset, |
2610 | int64_t bytes, int64_t *pnum) | |
2611 | { | |
2612 | int ret; | |
2613 | int64_t dummy; | |
2614 | IO_CODE(); | |
2615 | ||
2616 | ret = bdrv_co_common_block_status_above(bs, bs, true, false, offset, | |
2617 | bytes, pnum ? pnum : &dummy, NULL, | |
2618 | NULL, NULL); | |
2619 | if (ret < 0) { | |
2620 | return ret; | |
2621 | } | |
2622 | return !!(ret & BDRV_BLOCK_ALLOCATED); | |
2623 | } | |
2624 | ||
7c85803c AF |
2625 | int bdrv_is_allocated(BlockDriverState *bs, int64_t offset, int64_t bytes, |
2626 | int64_t *pnum) | |
61007b31 | 2627 | { |
7ddb99b9 EB |
2628 | int ret; |
2629 | int64_t dummy; | |
384a48fb | 2630 | IO_CODE(); |
d6a644bb | 2631 | |
3555a432 VSO |
2632 | ret = bdrv_common_block_status_above(bs, bs, true, false, offset, |
2633 | bytes, pnum ? pnum : &dummy, NULL, | |
a92b1b06 | 2634 | NULL, NULL); |
61007b31 SH |
2635 | if (ret < 0) { |
2636 | return ret; | |
2637 | } | |
2638 | return !!(ret & BDRV_BLOCK_ALLOCATED); | |
2639 | } | |
2640 | ||
7b52a921 EGE |
2641 | /* See bdrv_is_allocated_above for documentation */ |
2642 | int coroutine_fn bdrv_co_is_allocated_above(BlockDriverState *top, | |
2643 | BlockDriverState *base, | |
2644 | bool include_base, int64_t offset, | |
2645 | int64_t bytes, int64_t *pnum) | |
2646 | { | |
2647 | int depth; | |
2648 | int ret; | |
2649 | IO_CODE(); | |
2650 | ||
2651 | ret = bdrv_co_common_block_status_above(top, base, include_base, false, | |
2652 | offset, bytes, pnum, NULL, NULL, | |
2653 | &depth); | |
2654 | if (ret < 0) { | |
2655 | return ret; | |
2656 | } | |
2657 | ||
2658 | if (ret & BDRV_BLOCK_ALLOCATED) { | |
2659 | return depth; | |
2660 | } | |
2661 | return 0; | |
2662 | } | |
2663 | ||
61007b31 SH |
2664 | /* |
2665 | * Given an image chain: ... -> [BASE] -> [INTER1] -> [INTER2] -> [TOP] | |
2666 | * | |
a92b1b06 EB |
2667 | * Return a positive depth if (a prefix of) the given range is allocated |
2668 | * in any image between BASE and TOP (BASE is only included if include_base | |
2669 | * is set). Depth 1 is TOP, 2 is the first backing layer, and so forth. | |
170d3bd3 AS |
2670 | * BASE can be NULL to check if the given offset is allocated in any |
2671 | * image of the chain. Return 0 otherwise, or negative errno on | |
2672 | * failure. | |
61007b31 | 2673 | * |
51b0a488 EB |
2674 | * 'pnum' is set to the number of bytes (including and immediately |
2675 | * following the specified offset) that are known to be in the same | |
2676 | * allocated/unallocated state. Note that a subsequent call starting | |
2677 | * at 'offset + *pnum' may return the same allocation status (in other | |
2678 | * words, the result is not necessarily the maximum possible range); | |
2679 | * but 'pnum' will only be 0 when end of file is reached. | |
61007b31 SH |
2680 | */ |
2681 | int bdrv_is_allocated_above(BlockDriverState *top, | |
2682 | BlockDriverState *base, | |
170d3bd3 AS |
2683 | bool include_base, int64_t offset, |
2684 | int64_t bytes, int64_t *pnum) | |
61007b31 | 2685 | { |
a92b1b06 | 2686 | int depth; |
7b52a921 | 2687 | int ret; |
384a48fb | 2688 | IO_CODE(); |
7b52a921 EGE |
2689 | |
2690 | ret = bdrv_common_block_status_above(top, base, include_base, false, | |
2691 | offset, bytes, pnum, NULL, NULL, | |
2692 | &depth); | |
7e7e5100 VSO |
2693 | if (ret < 0) { |
2694 | return ret; | |
61007b31 SH |
2695 | } |
2696 | ||
a92b1b06 EB |
2697 | if (ret & BDRV_BLOCK_ALLOCATED) { |
2698 | return depth; | |
2699 | } | |
2700 | return 0; | |
61007b31 SH |
2701 | } |
2702 | ||
21c2283e | 2703 | int coroutine_fn |
b33b354f | 2704 | bdrv_co_readv_vmstate(BlockDriverState *bs, QEMUIOVector *qiov, int64_t pos) |
1a8ae822 KW |
2705 | { |
2706 | BlockDriver *drv = bs->drv; | |
c4db2e25 | 2707 | BlockDriverState *child_bs = bdrv_primary_bs(bs); |
b984b296 | 2708 | int ret; |
1581a70d | 2709 | IO_CODE(); |
1b3ff9fe | 2710 | assert_bdrv_graph_readable(); |
b984b296 VSO |
2711 | |
2712 | ret = bdrv_check_qiov_request(pos, qiov->size, qiov, 0, NULL); | |
2713 | if (ret < 0) { | |
2714 | return ret; | |
2715 | } | |
dc88a467 | 2716 | |
b33b354f VSO |
2717 | if (!drv) { |
2718 | return -ENOMEDIUM; | |
2719 | } | |
2720 | ||
dc88a467 | 2721 | bdrv_inc_in_flight(bs); |
1a8ae822 | 2722 | |
b33b354f VSO |
2723 | if (drv->bdrv_load_vmstate) { |
2724 | ret = drv->bdrv_load_vmstate(bs, qiov, pos); | |
c4db2e25 | 2725 | } else if (child_bs) { |
b33b354f | 2726 | ret = bdrv_co_readv_vmstate(child_bs, qiov, pos); |
b984b296 VSO |
2727 | } else { |
2728 | ret = -ENOTSUP; | |
1a8ae822 KW |
2729 | } |
2730 | ||
dc88a467 | 2731 | bdrv_dec_in_flight(bs); |
b33b354f | 2732 | |
dc88a467 | 2733 | return ret; |
1a8ae822 KW |
2734 | } |
2735 | ||
b33b354f VSO |
2736 | int coroutine_fn |
2737 | bdrv_co_writev_vmstate(BlockDriverState *bs, QEMUIOVector *qiov, int64_t pos) | |
61007b31 | 2738 | { |
b33b354f VSO |
2739 | BlockDriver *drv = bs->drv; |
2740 | BlockDriverState *child_bs = bdrv_primary_bs(bs); | |
b984b296 | 2741 | int ret; |
1581a70d | 2742 | IO_CODE(); |
1b3ff9fe | 2743 | assert_bdrv_graph_readable(); |
b984b296 VSO |
2744 | |
2745 | ret = bdrv_check_qiov_request(pos, qiov->size, qiov, 0, NULL); | |
2746 | if (ret < 0) { | |
2747 | return ret; | |
2748 | } | |
61007b31 | 2749 | |
b33b354f VSO |
2750 | if (!drv) { |
2751 | return -ENOMEDIUM; | |
b433d942 KW |
2752 | } |
2753 | ||
b33b354f | 2754 | bdrv_inc_in_flight(bs); |
61007b31 | 2755 | |
b33b354f VSO |
2756 | if (drv->bdrv_save_vmstate) { |
2757 | ret = drv->bdrv_save_vmstate(bs, qiov, pos); | |
2758 | } else if (child_bs) { | |
2759 | ret = bdrv_co_writev_vmstate(child_bs, qiov, pos); | |
b984b296 VSO |
2760 | } else { |
2761 | ret = -ENOTSUP; | |
b33b354f VSO |
2762 | } |
2763 | ||
2764 | bdrv_dec_in_flight(bs); | |
2765 | ||
2766 | return ret; | |
61007b31 SH |
2767 | } |
2768 | ||
b33b354f | 2769 | int bdrv_save_vmstate(BlockDriverState *bs, const uint8_t *buf, |
61007b31 | 2770 | int64_t pos, int size) |
5ddda0b8 | 2771 | { |
0d93ed08 | 2772 | QEMUIOVector qiov = QEMU_IOVEC_INIT_BUF(qiov, buf, size); |
b33b354f | 2773 | int ret = bdrv_writev_vmstate(bs, &qiov, pos); |
384a48fb | 2774 | IO_CODE(); |
b433d942 | 2775 | |
b33b354f | 2776 | return ret < 0 ? ret : size; |
5ddda0b8 KW |
2777 | } |
2778 | ||
b33b354f VSO |
2779 | int bdrv_load_vmstate(BlockDriverState *bs, uint8_t *buf, |
2780 | int64_t pos, int size) | |
61007b31 | 2781 | { |
b33b354f VSO |
2782 | QEMUIOVector qiov = QEMU_IOVEC_INIT_BUF(qiov, buf, size); |
2783 | int ret = bdrv_readv_vmstate(bs, &qiov, pos); | |
384a48fb | 2784 | IO_CODE(); |
b33b354f VSO |
2785 | |
2786 | return ret < 0 ? ret : size; | |
61007b31 SH |
2787 | } |
2788 | ||
2789 | /**************************************************************/ | |
2790 | /* async I/Os */ | |
2791 | ||
61007b31 SH |
2792 | void bdrv_aio_cancel(BlockAIOCB *acb) |
2793 | { | |
384a48fb | 2794 | IO_CODE(); |
61007b31 SH |
2795 | qemu_aio_ref(acb); |
2796 | bdrv_aio_cancel_async(acb); | |
2797 | while (acb->refcnt > 1) { | |
2798 | if (acb->aiocb_info->get_aio_context) { | |
2799 | aio_poll(acb->aiocb_info->get_aio_context(acb), true); | |
2800 | } else if (acb->bs) { | |
2f47da5f PB |
2801 | /* qemu_aio_ref and qemu_aio_unref are not thread-safe, so |
2802 | * assert that we're not using an I/O thread. Thread-safe | |
2803 | * code should use bdrv_aio_cancel_async exclusively. | |
2804 | */ | |
2805 | assert(bdrv_get_aio_context(acb->bs) == qemu_get_aio_context()); | |
61007b31 SH |
2806 | aio_poll(bdrv_get_aio_context(acb->bs), true); |
2807 | } else { | |
2808 | abort(); | |
2809 | } | |
2810 | } | |
2811 | qemu_aio_unref(acb); | |
2812 | } | |
2813 | ||
2814 | /* Async version of aio cancel. The caller is not blocked if the acb implements | |
2815 | * cancel_async, otherwise we do nothing and let the request normally complete. | |
2816 | * In either case the completion callback must be called. */ | |
2817 | void bdrv_aio_cancel_async(BlockAIOCB *acb) | |
2818 | { | |
384a48fb | 2819 | IO_CODE(); |
61007b31 SH |
2820 | if (acb->aiocb_info->cancel_async) { |
2821 | acb->aiocb_info->cancel_async(acb); | |
2822 | } | |
2823 | } | |
2824 | ||
61007b31 SH |
2825 | /**************************************************************/ |
2826 | /* Coroutine block device emulation */ | |
2827 | ||
61007b31 SH |
2828 | int coroutine_fn bdrv_co_flush(BlockDriverState *bs) |
2829 | { | |
883833e2 HR |
2830 | BdrvChild *primary_child = bdrv_primary_child(bs); |
2831 | BdrvChild *child; | |
49ca6259 FZ |
2832 | int current_gen; |
2833 | int ret = 0; | |
384a48fb | 2834 | IO_CODE(); |
49ca6259 FZ |
2835 | |
2836 | bdrv_inc_in_flight(bs); | |
61007b31 | 2837 | |
1e97be91 | 2838 | if (!bdrv_co_is_inserted(bs) || bdrv_is_read_only(bs) || |
1b6bc94d | 2839 | bdrv_is_sg(bs)) { |
49ca6259 | 2840 | goto early_exit; |
61007b31 SH |
2841 | } |
2842 | ||
3783fa3d | 2843 | qemu_co_mutex_lock(&bs->reqs_lock); |
d73415a3 | 2844 | current_gen = qatomic_read(&bs->write_gen); |
3ff2f67a EY |
2845 | |
2846 | /* Wait until any previous flushes are completed */ | |
99723548 | 2847 | while (bs->active_flush_req) { |
3783fa3d | 2848 | qemu_co_queue_wait(&bs->flush_queue, &bs->reqs_lock); |
3ff2f67a EY |
2849 | } |
2850 | ||
3783fa3d | 2851 | /* Flushes reach this point in nondecreasing current_gen order. */ |
99723548 | 2852 | bs->active_flush_req = true; |
3783fa3d | 2853 | qemu_co_mutex_unlock(&bs->reqs_lock); |
3ff2f67a | 2854 | |
c32b82af PD |
2855 | /* Write back all layers by calling one driver function */ |
2856 | if (bs->drv->bdrv_co_flush) { | |
2857 | ret = bs->drv->bdrv_co_flush(bs); | |
2858 | goto out; | |
2859 | } | |
2860 | ||
61007b31 | 2861 | /* Write back cached data to the OS even with cache=unsafe */ |
883833e2 | 2862 | BLKDBG_EVENT(primary_child, BLKDBG_FLUSH_TO_OS); |
61007b31 SH |
2863 | if (bs->drv->bdrv_co_flush_to_os) { |
2864 | ret = bs->drv->bdrv_co_flush_to_os(bs); | |
2865 | if (ret < 0) { | |
cdb5e315 | 2866 | goto out; |
61007b31 SH |
2867 | } |
2868 | } | |
2869 | ||
2870 | /* But don't actually force it to the disk with cache=unsafe */ | |
2871 | if (bs->open_flags & BDRV_O_NO_FLUSH) { | |
883833e2 | 2872 | goto flush_children; |
61007b31 SH |
2873 | } |
2874 | ||
3ff2f67a EY |
2875 | /* Check if we really need to flush anything */ |
2876 | if (bs->flushed_gen == current_gen) { | |
883833e2 | 2877 | goto flush_children; |
3ff2f67a EY |
2878 | } |
2879 | ||
883833e2 | 2880 | BLKDBG_EVENT(primary_child, BLKDBG_FLUSH_TO_DISK); |
d470ad42 HR |
2881 | if (!bs->drv) { |
2882 | /* bs->drv->bdrv_co_flush() might have ejected the BDS | |
2883 | * (even in case of apparent success) */ | |
2884 | ret = -ENOMEDIUM; | |
2885 | goto out; | |
2886 | } | |
61007b31 SH |
2887 | if (bs->drv->bdrv_co_flush_to_disk) { |
2888 | ret = bs->drv->bdrv_co_flush_to_disk(bs); | |
2889 | } else if (bs->drv->bdrv_aio_flush) { | |
2890 | BlockAIOCB *acb; | |
2891 | CoroutineIOCompletion co = { | |
2892 | .coroutine = qemu_coroutine_self(), | |
2893 | }; | |
2894 | ||
2895 | acb = bs->drv->bdrv_aio_flush(bs, bdrv_co_io_em_complete, &co); | |
2896 | if (acb == NULL) { | |
2897 | ret = -EIO; | |
2898 | } else { | |
2899 | qemu_coroutine_yield(); | |
2900 | ret = co.ret; | |
2901 | } | |
2902 | } else { | |
2903 | /* | |
2904 | * Some block drivers always operate in either writethrough or unsafe | |
2905 | * mode and don't support bdrv_flush therefore. Usually qemu doesn't | |
2906 | * know how the server works (because the behaviour is hardcoded or | |
2907 | * depends on server-side configuration), so we can't ensure that | |
2908 | * everything is safe on disk. Returning an error doesn't work because | |
2909 | * that would break guests even if the server operates in writethrough | |
2910 | * mode. | |
2911 | * | |
2912 | * Let's hope the user knows what he's doing. | |
2913 | */ | |
2914 | ret = 0; | |
2915 | } | |
3ff2f67a | 2916 | |
61007b31 | 2917 | if (ret < 0) { |
cdb5e315 | 2918 | goto out; |
61007b31 SH |
2919 | } |
2920 | ||
2921 | /* Now flush the underlying protocol. It will also have BDRV_O_NO_FLUSH | |
2922 | * in the case of cache=unsafe, so there are no useless flushes. | |
2923 | */ | |
883833e2 HR |
2924 | flush_children: |
2925 | ret = 0; | |
2926 | QLIST_FOREACH(child, &bs->children, next) { | |
2927 | if (child->perm & (BLK_PERM_WRITE | BLK_PERM_WRITE_UNCHANGED)) { | |
2928 | int this_child_ret = bdrv_co_flush(child->bs); | |
2929 | if (!ret) { | |
2930 | ret = this_child_ret; | |
2931 | } | |
2932 | } | |
2933 | } | |
2934 | ||
cdb5e315 | 2935 | out: |
3ff2f67a | 2936 | /* Notify any pending flushes that we have completed */ |
e6af1e08 KW |
2937 | if (ret == 0) { |
2938 | bs->flushed_gen = current_gen; | |
2939 | } | |
3783fa3d PB |
2940 | |
2941 | qemu_co_mutex_lock(&bs->reqs_lock); | |
99723548 | 2942 | bs->active_flush_req = false; |
156af3ac DL |
2943 | /* Return value is ignored - it's ok if wait queue is empty */ |
2944 | qemu_co_queue_next(&bs->flush_queue); | |
3783fa3d | 2945 | qemu_co_mutex_unlock(&bs->reqs_lock); |
3ff2f67a | 2946 | |
49ca6259 | 2947 | early_exit: |
99723548 | 2948 | bdrv_dec_in_flight(bs); |
cdb5e315 | 2949 | return ret; |
61007b31 SH |
2950 | } |
2951 | ||
d93e5726 VSO |
2952 | int coroutine_fn bdrv_co_pdiscard(BdrvChild *child, int64_t offset, |
2953 | int64_t bytes) | |
61007b31 | 2954 | { |
b1066c87 | 2955 | BdrvTrackedRequest req; |
39af49c0 VSO |
2956 | int ret; |
2957 | int64_t max_pdiscard; | |
3482b9bc | 2958 | int head, tail, align; |
0b9fd3f4 | 2959 | BlockDriverState *bs = child->bs; |
384a48fb | 2960 | IO_CODE(); |
61007b31 | 2961 | |
1e97be91 | 2962 | if (!bs || !bs->drv || !bdrv_co_is_inserted(bs)) { |
61007b31 SH |
2963 | return -ENOMEDIUM; |
2964 | } | |
2965 | ||
d6883bc9 VSO |
2966 | if (bdrv_has_readonly_bitmaps(bs)) { |
2967 | return -EPERM; | |
2968 | } | |
2969 | ||
69b55e03 | 2970 | ret = bdrv_check_request(offset, bytes, NULL); |
8b117001 VSO |
2971 | if (ret < 0) { |
2972 | return ret; | |
61007b31 SH |
2973 | } |
2974 | ||
61007b31 SH |
2975 | /* Do nothing if disabled. */ |
2976 | if (!(bs->open_flags & BDRV_O_UNMAP)) { | |
2977 | return 0; | |
2978 | } | |
2979 | ||
02aefe43 | 2980 | if (!bs->drv->bdrv_co_pdiscard && !bs->drv->bdrv_aio_pdiscard) { |
61007b31 SH |
2981 | return 0; |
2982 | } | |
2983 | ||
0bc329fb HR |
2984 | /* Invalidate the cached block-status data range if this discard overlaps */ |
2985 | bdrv_bsc_invalidate_range(bs, offset, bytes); | |
2986 | ||
3482b9bc EB |
2987 | /* Discard is advisory, but some devices track and coalesce |
2988 | * unaligned requests, so we must pass everything down rather than | |
2989 | * round here. Still, most devices will just silently ignore | |
2990 | * unaligned requests (by returning -ENOTSUP), so we must fragment | |
2991 | * the request accordingly. */ | |
02aefe43 | 2992 | align = MAX(bs->bl.pdiscard_alignment, bs->bl.request_alignment); |
b8d0a980 EB |
2993 | assert(align % bs->bl.request_alignment == 0); |
2994 | head = offset % align; | |
f5a5ca79 | 2995 | tail = (offset + bytes) % align; |
9f1963b3 | 2996 | |
99723548 | 2997 | bdrv_inc_in_flight(bs); |
f5a5ca79 | 2998 | tracked_request_begin(&req, bs, offset, bytes, BDRV_TRACKED_DISCARD); |
50824995 | 2999 | |
00695c27 | 3000 | ret = bdrv_co_write_req_prepare(child, offset, bytes, &req, 0); |
ec050f77 DL |
3001 | if (ret < 0) { |
3002 | goto out; | |
3003 | } | |
3004 | ||
6a8f3dbb | 3005 | max_pdiscard = QEMU_ALIGN_DOWN(MIN_NON_ZERO(bs->bl.max_pdiscard, INT64_MAX), |
9f1963b3 | 3006 | align); |
3482b9bc | 3007 | assert(max_pdiscard >= bs->bl.request_alignment); |
61007b31 | 3008 | |
f5a5ca79 | 3009 | while (bytes > 0) { |
d93e5726 | 3010 | int64_t num = bytes; |
3482b9bc EB |
3011 | |
3012 | if (head) { | |
3013 | /* Make small requests to get to alignment boundaries. */ | |
f5a5ca79 | 3014 | num = MIN(bytes, align - head); |
3482b9bc EB |
3015 | if (!QEMU_IS_ALIGNED(num, bs->bl.request_alignment)) { |
3016 | num %= bs->bl.request_alignment; | |
3017 | } | |
3018 | head = (head + num) % align; | |
3019 | assert(num < max_pdiscard); | |
3020 | } else if (tail) { | |
3021 | if (num > align) { | |
3022 | /* Shorten the request to the last aligned cluster. */ | |
3023 | num -= tail; | |
3024 | } else if (!QEMU_IS_ALIGNED(tail, bs->bl.request_alignment) && | |
3025 | tail > bs->bl.request_alignment) { | |
3026 | tail %= bs->bl.request_alignment; | |
3027 | num -= tail; | |
3028 | } | |
3029 | } | |
3030 | /* limit request size */ | |
3031 | if (num > max_pdiscard) { | |
3032 | num = max_pdiscard; | |
3033 | } | |
61007b31 | 3034 | |
d470ad42 HR |
3035 | if (!bs->drv) { |
3036 | ret = -ENOMEDIUM; | |
3037 | goto out; | |
3038 | } | |
47a5486d EB |
3039 | if (bs->drv->bdrv_co_pdiscard) { |
3040 | ret = bs->drv->bdrv_co_pdiscard(bs, offset, num); | |
61007b31 SH |
3041 | } else { |
3042 | BlockAIOCB *acb; | |
3043 | CoroutineIOCompletion co = { | |
3044 | .coroutine = qemu_coroutine_self(), | |
3045 | }; | |
3046 | ||
4da444a0 EB |
3047 | acb = bs->drv->bdrv_aio_pdiscard(bs, offset, num, |
3048 | bdrv_co_io_em_complete, &co); | |
61007b31 | 3049 | if (acb == NULL) { |
b1066c87 FZ |
3050 | ret = -EIO; |
3051 | goto out; | |
61007b31 SH |
3052 | } else { |
3053 | qemu_coroutine_yield(); | |
3054 | ret = co.ret; | |
3055 | } | |
3056 | } | |
3057 | if (ret && ret != -ENOTSUP) { | |
b1066c87 | 3058 | goto out; |
61007b31 SH |
3059 | } |
3060 | ||
9f1963b3 | 3061 | offset += num; |
f5a5ca79 | 3062 | bytes -= num; |
61007b31 | 3063 | } |
b1066c87 FZ |
3064 | ret = 0; |
3065 | out: | |
00695c27 | 3066 | bdrv_co_write_req_finish(child, req.offset, req.bytes, &req, ret); |
b1066c87 | 3067 | tracked_request_end(&req); |
99723548 | 3068 | bdrv_dec_in_flight(bs); |
b1066c87 | 3069 | return ret; |
61007b31 SH |
3070 | } |
3071 | ||
881a4c55 | 3072 | int coroutine_fn bdrv_co_ioctl(BlockDriverState *bs, int req, void *buf) |
61007b31 SH |
3073 | { |
3074 | BlockDriver *drv = bs->drv; | |
5c5ae76a FZ |
3075 | CoroutineIOCompletion co = { |
3076 | .coroutine = qemu_coroutine_self(), | |
3077 | }; | |
3078 | BlockAIOCB *acb; | |
384a48fb | 3079 | IO_CODE(); |
61007b31 | 3080 | |
99723548 | 3081 | bdrv_inc_in_flight(bs); |
16a389dc | 3082 | if (!drv || (!drv->bdrv_aio_ioctl && !drv->bdrv_co_ioctl)) { |
5c5ae76a FZ |
3083 | co.ret = -ENOTSUP; |
3084 | goto out; | |
3085 | } | |
3086 | ||
16a389dc KW |
3087 | if (drv->bdrv_co_ioctl) { |
3088 | co.ret = drv->bdrv_co_ioctl(bs, req, buf); | |
3089 | } else { | |
3090 | acb = drv->bdrv_aio_ioctl(bs, req, buf, bdrv_co_io_em_complete, &co); | |
3091 | if (!acb) { | |
3092 | co.ret = -ENOTSUP; | |
3093 | goto out; | |
3094 | } | |
3095 | qemu_coroutine_yield(); | |
5c5ae76a | 3096 | } |
5c5ae76a | 3097 | out: |
99723548 | 3098 | bdrv_dec_in_flight(bs); |
5c5ae76a FZ |
3099 | return co.ret; |
3100 | } | |
3101 | ||
61007b31 SH |
3102 | void *qemu_blockalign(BlockDriverState *bs, size_t size) |
3103 | { | |
384a48fb | 3104 | IO_CODE(); |
61007b31 SH |
3105 | return qemu_memalign(bdrv_opt_mem_align(bs), size); |
3106 | } | |
3107 | ||
3108 | void *qemu_blockalign0(BlockDriverState *bs, size_t size) | |
3109 | { | |
384a48fb | 3110 | IO_CODE(); |
61007b31 SH |
3111 | return memset(qemu_blockalign(bs, size), 0, size); |
3112 | } | |
3113 | ||
3114 | void *qemu_try_blockalign(BlockDriverState *bs, size_t size) | |
3115 | { | |
3116 | size_t align = bdrv_opt_mem_align(bs); | |
384a48fb | 3117 | IO_CODE(); |
61007b31 SH |
3118 | |
3119 | /* Ensure that NULL is never returned on success */ | |
3120 | assert(align > 0); | |
3121 | if (size == 0) { | |
3122 | size = align; | |
3123 | } | |
3124 | ||
3125 | return qemu_try_memalign(align, size); | |
3126 | } | |
3127 | ||
3128 | void *qemu_try_blockalign0(BlockDriverState *bs, size_t size) | |
3129 | { | |
3130 | void *mem = qemu_try_blockalign(bs, size); | |
384a48fb | 3131 | IO_CODE(); |
61007b31 SH |
3132 | |
3133 | if (mem) { | |
3134 | memset(mem, 0, size); | |
3135 | } | |
3136 | ||
3137 | return mem; | |
3138 | } | |
3139 | ||
8f497454 | 3140 | void coroutine_fn bdrv_co_io_plug(BlockDriverState *bs) |
61007b31 | 3141 | { |
6b98bd64 | 3142 | BdrvChild *child; |
384a48fb | 3143 | IO_CODE(); |
6b98bd64 PB |
3144 | |
3145 | QLIST_FOREACH(child, &bs->children, next) { | |
8f497454 | 3146 | bdrv_co_io_plug(child->bs); |
6b98bd64 PB |
3147 | } |
3148 | ||
d73415a3 | 3149 | if (qatomic_fetch_inc(&bs->io_plugged) == 0) { |
6b98bd64 | 3150 | BlockDriver *drv = bs->drv; |
8f497454 EGE |
3151 | if (drv && drv->bdrv_co_io_plug) { |
3152 | drv->bdrv_co_io_plug(bs); | |
6b98bd64 | 3153 | } |
61007b31 SH |
3154 | } |
3155 | } | |
3156 | ||
09d9fc97 | 3157 | void coroutine_fn bdrv_co_io_unplug(BlockDriverState *bs) |
61007b31 | 3158 | { |
6b98bd64 | 3159 | BdrvChild *child; |
384a48fb | 3160 | IO_CODE(); |
6b98bd64 PB |
3161 | |
3162 | assert(bs->io_plugged); | |
d73415a3 | 3163 | if (qatomic_fetch_dec(&bs->io_plugged) == 1) { |
6b98bd64 | 3164 | BlockDriver *drv = bs->drv; |
09d9fc97 EGE |
3165 | if (drv && drv->bdrv_co_io_unplug) { |
3166 | drv->bdrv_co_io_unplug(bs); | |
6b98bd64 PB |
3167 | } |
3168 | } | |
3169 | ||
3170 | QLIST_FOREACH(child, &bs->children, next) { | |
09d9fc97 | 3171 | bdrv_co_io_unplug(child->bs); |
61007b31 SH |
3172 | } |
3173 | } | |
23d0ba93 | 3174 | |
f4ec04ba SH |
3175 | /* Helper that undoes bdrv_register_buf() when it fails partway through */ |
3176 | static void bdrv_register_buf_rollback(BlockDriverState *bs, | |
3177 | void *host, | |
3178 | size_t size, | |
3179 | BdrvChild *final_child) | |
3180 | { | |
3181 | BdrvChild *child; | |
3182 | ||
3183 | QLIST_FOREACH(child, &bs->children, next) { | |
3184 | if (child == final_child) { | |
3185 | break; | |
3186 | } | |
3187 | ||
3188 | bdrv_unregister_buf(child->bs, host, size); | |
3189 | } | |
3190 | ||
3191 | if (bs->drv && bs->drv->bdrv_unregister_buf) { | |
3192 | bs->drv->bdrv_unregister_buf(bs, host, size); | |
3193 | } | |
3194 | } | |
3195 | ||
3196 | bool bdrv_register_buf(BlockDriverState *bs, void *host, size_t size, | |
3197 | Error **errp) | |
23d0ba93 FZ |
3198 | { |
3199 | BdrvChild *child; | |
3200 | ||
f791bf7f | 3201 | GLOBAL_STATE_CODE(); |
23d0ba93 | 3202 | if (bs->drv && bs->drv->bdrv_register_buf) { |
f4ec04ba SH |
3203 | if (!bs->drv->bdrv_register_buf(bs, host, size, errp)) { |
3204 | return false; | |
3205 | } | |
23d0ba93 FZ |
3206 | } |
3207 | QLIST_FOREACH(child, &bs->children, next) { | |
f4ec04ba SH |
3208 | if (!bdrv_register_buf(child->bs, host, size, errp)) { |
3209 | bdrv_register_buf_rollback(bs, host, size, child); | |
3210 | return false; | |
3211 | } | |
23d0ba93 | 3212 | } |
f4ec04ba | 3213 | return true; |
23d0ba93 FZ |
3214 | } |
3215 | ||
4f384011 | 3216 | void bdrv_unregister_buf(BlockDriverState *bs, void *host, size_t size) |
23d0ba93 FZ |
3217 | { |
3218 | BdrvChild *child; | |
3219 | ||
f791bf7f | 3220 | GLOBAL_STATE_CODE(); |
23d0ba93 | 3221 | if (bs->drv && bs->drv->bdrv_unregister_buf) { |
4f384011 | 3222 | bs->drv->bdrv_unregister_buf(bs, host, size); |
23d0ba93 FZ |
3223 | } |
3224 | QLIST_FOREACH(child, &bs->children, next) { | |
4f384011 | 3225 | bdrv_unregister_buf(child->bs, host, size); |
23d0ba93 FZ |
3226 | } |
3227 | } | |
fcc67678 | 3228 | |
67b51fb9 | 3229 | static int coroutine_fn bdrv_co_copy_range_internal( |
a5215b8f VSO |
3230 | BdrvChild *src, int64_t src_offset, BdrvChild *dst, |
3231 | int64_t dst_offset, int64_t bytes, | |
67b51fb9 VSO |
3232 | BdrvRequestFlags read_flags, BdrvRequestFlags write_flags, |
3233 | bool recurse_src) | |
fcc67678 | 3234 | { |
999658a0 | 3235 | BdrvTrackedRequest req; |
fcc67678 FZ |
3236 | int ret; |
3237 | ||
fe0480d6 KW |
3238 | /* TODO We can support BDRV_REQ_NO_FALLBACK here */ |
3239 | assert(!(read_flags & BDRV_REQ_NO_FALLBACK)); | |
3240 | assert(!(write_flags & BDRV_REQ_NO_FALLBACK)); | |
45e62b46 VSO |
3241 | assert(!(read_flags & BDRV_REQ_NO_WAIT)); |
3242 | assert(!(write_flags & BDRV_REQ_NO_WAIT)); | |
fe0480d6 | 3243 | |
1e97be91 | 3244 | if (!dst || !dst->bs || !bdrv_co_is_inserted(dst->bs)) { |
fcc67678 FZ |
3245 | return -ENOMEDIUM; |
3246 | } | |
63f4ad11 | 3247 | ret = bdrv_check_request32(dst_offset, bytes, NULL, 0); |
fcc67678 FZ |
3248 | if (ret) { |
3249 | return ret; | |
3250 | } | |
67b51fb9 VSO |
3251 | if (write_flags & BDRV_REQ_ZERO_WRITE) { |
3252 | return bdrv_co_pwrite_zeroes(dst, dst_offset, bytes, write_flags); | |
fcc67678 FZ |
3253 | } |
3254 | ||
1e97be91 | 3255 | if (!src || !src->bs || !bdrv_co_is_inserted(src->bs)) { |
d4d3e5a0 FZ |
3256 | return -ENOMEDIUM; |
3257 | } | |
63f4ad11 | 3258 | ret = bdrv_check_request32(src_offset, bytes, NULL, 0); |
d4d3e5a0 FZ |
3259 | if (ret) { |
3260 | return ret; | |
3261 | } | |
3262 | ||
fcc67678 FZ |
3263 | if (!src->bs->drv->bdrv_co_copy_range_from |
3264 | || !dst->bs->drv->bdrv_co_copy_range_to | |
3265 | || src->bs->encrypted || dst->bs->encrypted) { | |
3266 | return -ENOTSUP; | |
3267 | } | |
37aec7d7 | 3268 | |
fcc67678 | 3269 | if (recurse_src) { |
999658a0 VSO |
3270 | bdrv_inc_in_flight(src->bs); |
3271 | tracked_request_begin(&req, src->bs, src_offset, bytes, | |
3272 | BDRV_TRACKED_READ); | |
3273 | ||
09d2f948 VSO |
3274 | /* BDRV_REQ_SERIALISING is only for write operation */ |
3275 | assert(!(read_flags & BDRV_REQ_SERIALISING)); | |
c53cb427 | 3276 | bdrv_wait_serialising_requests(&req); |
999658a0 | 3277 | |
37aec7d7 FZ |
3278 | ret = src->bs->drv->bdrv_co_copy_range_from(src->bs, |
3279 | src, src_offset, | |
3280 | dst, dst_offset, | |
67b51fb9 VSO |
3281 | bytes, |
3282 | read_flags, write_flags); | |
999658a0 VSO |
3283 | |
3284 | tracked_request_end(&req); | |
3285 | bdrv_dec_in_flight(src->bs); | |
fcc67678 | 3286 | } else { |
999658a0 VSO |
3287 | bdrv_inc_in_flight(dst->bs); |
3288 | tracked_request_begin(&req, dst->bs, dst_offset, bytes, | |
3289 | BDRV_TRACKED_WRITE); | |
0eb1e891 FZ |
3290 | ret = bdrv_co_write_req_prepare(dst, dst_offset, bytes, &req, |
3291 | write_flags); | |
3292 | if (!ret) { | |
3293 | ret = dst->bs->drv->bdrv_co_copy_range_to(dst->bs, | |
3294 | src, src_offset, | |
3295 | dst, dst_offset, | |
3296 | bytes, | |
3297 | read_flags, write_flags); | |
3298 | } | |
3299 | bdrv_co_write_req_finish(dst, dst_offset, bytes, &req, ret); | |
999658a0 VSO |
3300 | tracked_request_end(&req); |
3301 | bdrv_dec_in_flight(dst->bs); | |
fcc67678 | 3302 | } |
999658a0 | 3303 | |
37aec7d7 | 3304 | return ret; |
fcc67678 FZ |
3305 | } |
3306 | ||
3307 | /* Copy range from @src to @dst. | |
3308 | * | |
3309 | * See the comment of bdrv_co_copy_range for the parameter and return value | |
3310 | * semantics. */ | |
a5215b8f VSO |
3311 | int coroutine_fn bdrv_co_copy_range_from(BdrvChild *src, int64_t src_offset, |
3312 | BdrvChild *dst, int64_t dst_offset, | |
3313 | int64_t bytes, | |
67b51fb9 VSO |
3314 | BdrvRequestFlags read_flags, |
3315 | BdrvRequestFlags write_flags) | |
fcc67678 | 3316 | { |
967d7905 | 3317 | IO_CODE(); |
ecc983a5 FZ |
3318 | trace_bdrv_co_copy_range_from(src, src_offset, dst, dst_offset, bytes, |
3319 | read_flags, write_flags); | |
fcc67678 | 3320 | return bdrv_co_copy_range_internal(src, src_offset, dst, dst_offset, |
67b51fb9 | 3321 | bytes, read_flags, write_flags, true); |
fcc67678 FZ |
3322 | } |
3323 | ||
3324 | /* Copy range from @src to @dst. | |
3325 | * | |
3326 | * See the comment of bdrv_co_copy_range for the parameter and return value | |
3327 | * semantics. */ | |
a5215b8f VSO |
3328 | int coroutine_fn bdrv_co_copy_range_to(BdrvChild *src, int64_t src_offset, |
3329 | BdrvChild *dst, int64_t dst_offset, | |
3330 | int64_t bytes, | |
67b51fb9 VSO |
3331 | BdrvRequestFlags read_flags, |
3332 | BdrvRequestFlags write_flags) | |
fcc67678 | 3333 | { |
967d7905 | 3334 | IO_CODE(); |
ecc983a5 FZ |
3335 | trace_bdrv_co_copy_range_to(src, src_offset, dst, dst_offset, bytes, |
3336 | read_flags, write_flags); | |
fcc67678 | 3337 | return bdrv_co_copy_range_internal(src, src_offset, dst, dst_offset, |
67b51fb9 | 3338 | bytes, read_flags, write_flags, false); |
fcc67678 FZ |
3339 | } |
3340 | ||
a5215b8f VSO |
3341 | int coroutine_fn bdrv_co_copy_range(BdrvChild *src, int64_t src_offset, |
3342 | BdrvChild *dst, int64_t dst_offset, | |
3343 | int64_t bytes, BdrvRequestFlags read_flags, | |
67b51fb9 | 3344 | BdrvRequestFlags write_flags) |
fcc67678 | 3345 | { |
384a48fb | 3346 | IO_CODE(); |
37aec7d7 FZ |
3347 | return bdrv_co_copy_range_from(src, src_offset, |
3348 | dst, dst_offset, | |
67b51fb9 | 3349 | bytes, read_flags, write_flags); |
fcc67678 | 3350 | } |
3d9f2d2a KW |
3351 | |
3352 | static void bdrv_parent_cb_resize(BlockDriverState *bs) | |
3353 | { | |
3354 | BdrvChild *c; | |
3355 | QLIST_FOREACH(c, &bs->parents, next_parent) { | |
bd86fb99 HR |
3356 | if (c->klass->resize) { |
3357 | c->klass->resize(c); | |
3d9f2d2a KW |
3358 | } |
3359 | } | |
3360 | } | |
3361 | ||
3362 | /** | |
3363 | * Truncate file to 'offset' bytes (needed only for file protocols) | |
c80d8b06 HR |
3364 | * |
3365 | * If 'exact' is true, the file must be resized to exactly the given | |
3366 | * 'offset'. Otherwise, it is sufficient for the node to be at least | |
3367 | * 'offset' bytes in length. | |
3d9f2d2a | 3368 | */ |
c80d8b06 | 3369 | int coroutine_fn bdrv_co_truncate(BdrvChild *child, int64_t offset, bool exact, |
7b8e4857 KW |
3370 | PreallocMode prealloc, BdrvRequestFlags flags, |
3371 | Error **errp) | |
3d9f2d2a KW |
3372 | { |
3373 | BlockDriverState *bs = child->bs; | |
23b93525 | 3374 | BdrvChild *filtered, *backing; |
3d9f2d2a | 3375 | BlockDriver *drv = bs->drv; |
1bc5f09f KW |
3376 | BdrvTrackedRequest req; |
3377 | int64_t old_size, new_bytes; | |
3d9f2d2a | 3378 | int ret; |
384a48fb | 3379 | IO_CODE(); |
3d9f2d2a KW |
3380 | |
3381 | /* if bs->drv == NULL, bs is closed, so there's nothing to do here */ | |
3382 | if (!drv) { | |
3383 | error_setg(errp, "No medium inserted"); | |
3384 | return -ENOMEDIUM; | |
3385 | } | |
3386 | if (offset < 0) { | |
3387 | error_setg(errp, "Image size cannot be negative"); | |
3388 | return -EINVAL; | |
3389 | } | |
3390 | ||
69b55e03 | 3391 | ret = bdrv_check_request(offset, 0, errp); |
8b117001 | 3392 | if (ret < 0) { |
8b117001 VSO |
3393 | return ret; |
3394 | } | |
3395 | ||
1bc5f09f KW |
3396 | old_size = bdrv_getlength(bs); |
3397 | if (old_size < 0) { | |
3398 | error_setg_errno(errp, -old_size, "Failed to get old image size"); | |
3399 | return old_size; | |
3400 | } | |
3401 | ||
97efa869 EB |
3402 | if (bdrv_is_read_only(bs)) { |
3403 | error_setg(errp, "Image is read-only"); | |
3404 | return -EACCES; | |
3405 | } | |
3406 | ||
1bc5f09f KW |
3407 | if (offset > old_size) { |
3408 | new_bytes = offset - old_size; | |
3409 | } else { | |
3410 | new_bytes = 0; | |
3411 | } | |
3412 | ||
3d9f2d2a | 3413 | bdrv_inc_in_flight(bs); |
5416a11e FZ |
3414 | tracked_request_begin(&req, bs, offset - new_bytes, new_bytes, |
3415 | BDRV_TRACKED_TRUNCATE); | |
1bc5f09f KW |
3416 | |
3417 | /* If we are growing the image and potentially using preallocation for the | |
3418 | * new area, we need to make sure that no write requests are made to it | |
3419 | * concurrently or they might be overwritten by preallocation. */ | |
3420 | if (new_bytes) { | |
8ac5aab2 | 3421 | bdrv_make_request_serialising(&req, 1); |
cd47d792 | 3422 | } |
cd47d792 FZ |
3423 | ret = bdrv_co_write_req_prepare(child, offset - new_bytes, new_bytes, &req, |
3424 | 0); | |
3425 | if (ret < 0) { | |
3426 | error_setg_errno(errp, -ret, | |
3427 | "Failed to prepare request for truncation"); | |
3428 | goto out; | |
1bc5f09f | 3429 | } |
3d9f2d2a | 3430 | |
93393e69 | 3431 | filtered = bdrv_filter_child(bs); |
23b93525 | 3432 | backing = bdrv_cow_child(bs); |
93393e69 | 3433 | |
955c7d66 KW |
3434 | /* |
3435 | * If the image has a backing file that is large enough that it would | |
3436 | * provide data for the new area, we cannot leave it unallocated because | |
3437 | * then the backing file content would become visible. Instead, zero-fill | |
3438 | * the new area. | |
3439 | * | |
3440 | * Note that if the image has a backing file, but was opened without the | |
3441 | * backing file, taking care of keeping things consistent with that backing | |
3442 | * file is the user's responsibility. | |
3443 | */ | |
23b93525 | 3444 | if (new_bytes && backing) { |
955c7d66 KW |
3445 | int64_t backing_len; |
3446 | ||
bd53086e | 3447 | backing_len = bdrv_co_getlength(backing->bs); |
955c7d66 KW |
3448 | if (backing_len < 0) { |
3449 | ret = backing_len; | |
3450 | error_setg_errno(errp, -ret, "Could not get backing file size"); | |
3451 | goto out; | |
3452 | } | |
3453 | ||
3454 | if (backing_len > old_size) { | |
3455 | flags |= BDRV_REQ_ZERO_WRITE; | |
3456 | } | |
3457 | } | |
3458 | ||
6b7e8f8b | 3459 | if (drv->bdrv_co_truncate) { |
92b92799 KW |
3460 | if (flags & ~bs->supported_truncate_flags) { |
3461 | error_setg(errp, "Block driver does not support requested flags"); | |
3462 | ret = -ENOTSUP; | |
3463 | goto out; | |
3464 | } | |
3465 | ret = drv->bdrv_co_truncate(bs, offset, exact, prealloc, flags, errp); | |
93393e69 HR |
3466 | } else if (filtered) { |
3467 | ret = bdrv_co_truncate(filtered, offset, exact, prealloc, flags, errp); | |
6b7e8f8b | 3468 | } else { |
3d9f2d2a KW |
3469 | error_setg(errp, "Image format driver does not support resize"); |
3470 | ret = -ENOTSUP; | |
3471 | goto out; | |
3472 | } | |
3d9f2d2a KW |
3473 | if (ret < 0) { |
3474 | goto out; | |
3475 | } | |
6b7e8f8b | 3476 | |
bd53086e | 3477 | ret = bdrv_co_refresh_total_sectors(bs, offset >> BDRV_SECTOR_BITS); |
3d9f2d2a KW |
3478 | if (ret < 0) { |
3479 | error_setg_errno(errp, -ret, "Could not refresh total sector count"); | |
3480 | } else { | |
3481 | offset = bs->total_sectors * BDRV_SECTOR_SIZE; | |
3482 | } | |
c057960c EGE |
3483 | /* |
3484 | * It's possible that truncation succeeded but bdrv_refresh_total_sectors | |
cd47d792 | 3485 | * failed, but the latter doesn't affect how we should finish the request. |
c057960c EGE |
3486 | * Pass 0 as the last parameter so that dirty bitmaps etc. are handled. |
3487 | */ | |
cd47d792 | 3488 | bdrv_co_write_req_finish(child, offset - new_bytes, new_bytes, &req, 0); |
3d9f2d2a KW |
3489 | |
3490 | out: | |
1bc5f09f | 3491 | tracked_request_end(&req); |
3d9f2d2a | 3492 | bdrv_dec_in_flight(bs); |
1bc5f09f | 3493 | |
3d9f2d2a KW |
3494 | return ret; |
3495 | } | |
bd54669a VSO |
3496 | |
3497 | void bdrv_cancel_in_flight(BlockDriverState *bs) | |
3498 | { | |
f791bf7f | 3499 | GLOBAL_STATE_CODE(); |
bd54669a VSO |
3500 | if (!bs || !bs->drv) { |
3501 | return; | |
3502 | } | |
3503 | ||
3504 | if (bs->drv->bdrv_cancel_in_flight) { | |
3505 | bs->drv->bdrv_cancel_in_flight(bs); | |
3506 | } | |
3507 | } | |
ce14f3b4 VSO |
3508 | |
3509 | int coroutine_fn | |
3510 | bdrv_co_preadv_snapshot(BdrvChild *child, int64_t offset, int64_t bytes, | |
3511 | QEMUIOVector *qiov, size_t qiov_offset) | |
3512 | { | |
3513 | BlockDriverState *bs = child->bs; | |
3514 | BlockDriver *drv = bs->drv; | |
3515 | int ret; | |
3516 | IO_CODE(); | |
3517 | ||
3518 | if (!drv) { | |
3519 | return -ENOMEDIUM; | |
3520 | } | |
3521 | ||
3522 | if (!drv->bdrv_co_preadv_snapshot) { | |
3523 | return -ENOTSUP; | |
3524 | } | |
3525 | ||
3526 | bdrv_inc_in_flight(bs); | |
3527 | ret = drv->bdrv_co_preadv_snapshot(bs, offset, bytes, qiov, qiov_offset); | |
3528 | bdrv_dec_in_flight(bs); | |
3529 | ||
3530 | return ret; | |
3531 | } | |
3532 | ||
3533 | int coroutine_fn | |
3534 | bdrv_co_snapshot_block_status(BlockDriverState *bs, | |
3535 | bool want_zero, int64_t offset, int64_t bytes, | |
3536 | int64_t *pnum, int64_t *map, | |
3537 | BlockDriverState **file) | |
3538 | { | |
3539 | BlockDriver *drv = bs->drv; | |
3540 | int ret; | |
3541 | IO_CODE(); | |
3542 | ||
3543 | if (!drv) { | |
3544 | return -ENOMEDIUM; | |
3545 | } | |
3546 | ||
3547 | if (!drv->bdrv_co_snapshot_block_status) { | |
3548 | return -ENOTSUP; | |
3549 | } | |
3550 | ||
3551 | bdrv_inc_in_flight(bs); | |
3552 | ret = drv->bdrv_co_snapshot_block_status(bs, want_zero, offset, bytes, | |
3553 | pnum, map, file); | |
3554 | bdrv_dec_in_flight(bs); | |
3555 | ||
3556 | return ret; | |
3557 | } | |
3558 | ||
3559 | int coroutine_fn | |
3560 | bdrv_co_pdiscard_snapshot(BlockDriverState *bs, int64_t offset, int64_t bytes) | |
3561 | { | |
3562 | BlockDriver *drv = bs->drv; | |
3563 | int ret; | |
3564 | IO_CODE(); | |
3565 | ||
3566 | if (!drv) { | |
3567 | return -ENOMEDIUM; | |
3568 | } | |
3569 | ||
3570 | if (!drv->bdrv_co_pdiscard_snapshot) { | |
3571 | return -ENOTSUP; | |
3572 | } | |
3573 | ||
3574 | bdrv_inc_in_flight(bs); | |
3575 | ret = drv->bdrv_co_pdiscard_snapshot(bs, offset, bytes); | |
3576 | bdrv_dec_in_flight(bs); | |
3577 | ||
3578 | return ret; | |
3579 | } |