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fd66dbd4 SH |
1 | /* SPDX-License-Identifier: LGPL-2.1-or-later */ |
2 | /* | |
3 | * libblkio BlockDriver | |
4 | * | |
5 | * Copyright Red Hat, Inc. | |
6 | * | |
7 | * Author: | |
8 | * Stefan Hajnoczi <stefanha@redhat.com> | |
9 | */ | |
10 | ||
11 | #include "qemu/osdep.h" | |
12 | #include <blkio.h> | |
13 | #include "block/block_int.h" | |
c5640b3e SH |
14 | #include "exec/memory.h" |
15 | #include "exec/cpu-common.h" /* for qemu_ram_get_fd() */ | |
fd66dbd4 | 16 | #include "qapi/error.h" |
c5640b3e | 17 | #include "qemu/error-report.h" |
fd66dbd4 SH |
18 | #include "qapi/qmp/qdict.h" |
19 | #include "qemu/module.h" | |
c5640b3e | 20 | #include "exec/memory.h" /* for ram_block_discard_disable() */ |
fd66dbd4 | 21 | |
4f01a9bb PK |
22 | #include "block/block-io.h" |
23 | ||
fd66dbd4 SH |
24 | /* |
25 | * Keep the QEMU BlockDriver names identical to the libblkio driver names. | |
26 | * Using macros instead of typing out the string literals avoids typos. | |
27 | */ | |
28 | #define DRIVER_IO_URING "io_uring" | |
29 | #define DRIVER_NVME_IO_URING "nvme-io_uring" | |
03d9e4c0 | 30 | #define DRIVER_VIRTIO_BLK_VFIO_PCI "virtio-blk-vfio-pci" |
fd66dbd4 SH |
31 | #define DRIVER_VIRTIO_BLK_VHOST_USER "virtio-blk-vhost-user" |
32 | #define DRIVER_VIRTIO_BLK_VHOST_VDPA "virtio-blk-vhost-vdpa" | |
33 | ||
34 | /* | |
35 | * Allocated bounce buffers are kept in a list sorted by buffer address. | |
36 | */ | |
37 | typedef struct BlkioBounceBuf { | |
38 | QLIST_ENTRY(BlkioBounceBuf) next; | |
39 | ||
40 | /* The bounce buffer */ | |
41 | struct iovec buf; | |
42 | } BlkioBounceBuf; | |
43 | ||
44 | typedef struct { | |
45 | /* | |
46 | * libblkio is not thread-safe so this lock protects ->blkio and | |
47 | * ->blkioq. | |
48 | */ | |
49 | QemuMutex blkio_lock; | |
50 | struct blkio *blkio; | |
51 | struct blkioq *blkioq; /* make this multi-queue in the future... */ | |
52 | int completion_fd; | |
53 | ||
54 | /* | |
55 | * Polling fetches the next completion into this field. | |
56 | * | |
57 | * No lock is necessary since only one thread calls aio_poll() and invokes | |
58 | * fd and poll handlers. | |
59 | */ | |
60 | struct blkio_completion poll_completion; | |
61 | ||
62 | /* | |
63 | * Protects ->bounce_pool, ->bounce_bufs, ->bounce_available. | |
64 | * | |
65 | * Lock ordering: ->bounce_lock before ->blkio_lock. | |
66 | */ | |
67 | CoMutex bounce_lock; | |
68 | ||
69 | /* Bounce buffer pool */ | |
70 | struct blkio_mem_region bounce_pool; | |
71 | ||
72 | /* Sorted list of allocated bounce buffers */ | |
73 | QLIST_HEAD(, BlkioBounceBuf) bounce_bufs; | |
74 | ||
75 | /* Queue for coroutines waiting for bounce buffer space */ | |
76 | CoQueue bounce_available; | |
77 | ||
78 | /* The value of the "mem-region-alignment" property */ | |
79 | size_t mem_region_alignment; | |
80 | ||
81 | /* Can we skip adding/deleting blkio_mem_regions? */ | |
82 | bool needs_mem_regions; | |
c5640b3e SH |
83 | |
84 | /* Are file descriptors necessary for blkio_mem_regions? */ | |
85 | bool needs_mem_region_fd; | |
86 | ||
87 | /* Are madvise(MADV_DONTNEED)-style operations unavailable? */ | |
88 | bool may_pin_mem_regions; | |
fd66dbd4 SH |
89 | } BDRVBlkioState; |
90 | ||
91 | /* Called with s->bounce_lock held */ | |
92 | static int blkio_resize_bounce_pool(BDRVBlkioState *s, int64_t bytes) | |
93 | { | |
94 | /* There can be no allocated bounce buffers during resize */ | |
95 | assert(QLIST_EMPTY(&s->bounce_bufs)); | |
96 | ||
97 | /* Pad size to reduce frequency of resize calls */ | |
98 | bytes += 128 * 1024; | |
99 | ||
100 | WITH_QEMU_LOCK_GUARD(&s->blkio_lock) { | |
101 | int ret; | |
102 | ||
103 | if (s->bounce_pool.addr) { | |
104 | blkio_unmap_mem_region(s->blkio, &s->bounce_pool); | |
105 | blkio_free_mem_region(s->blkio, &s->bounce_pool); | |
106 | memset(&s->bounce_pool, 0, sizeof(s->bounce_pool)); | |
107 | } | |
108 | ||
109 | /* Automatically freed when s->blkio is destroyed */ | |
110 | ret = blkio_alloc_mem_region(s->blkio, &s->bounce_pool, bytes); | |
111 | if (ret < 0) { | |
112 | return ret; | |
113 | } | |
114 | ||
115 | ret = blkio_map_mem_region(s->blkio, &s->bounce_pool); | |
116 | if (ret < 0) { | |
117 | blkio_free_mem_region(s->blkio, &s->bounce_pool); | |
118 | memset(&s->bounce_pool, 0, sizeof(s->bounce_pool)); | |
119 | return ret; | |
120 | } | |
121 | } | |
122 | ||
123 | return 0; | |
124 | } | |
125 | ||
126 | /* Called with s->bounce_lock held */ | |
127 | static bool | |
128 | blkio_do_alloc_bounce_buffer(BDRVBlkioState *s, BlkioBounceBuf *bounce, | |
129 | int64_t bytes) | |
130 | { | |
131 | void *addr = s->bounce_pool.addr; | |
132 | BlkioBounceBuf *cur = NULL; | |
133 | BlkioBounceBuf *prev = NULL; | |
134 | ptrdiff_t space; | |
135 | ||
136 | /* | |
137 | * This is just a linear search over the holes between requests. An | |
138 | * efficient allocator would be nice. | |
139 | */ | |
140 | QLIST_FOREACH(cur, &s->bounce_bufs, next) { | |
141 | space = cur->buf.iov_base - addr; | |
142 | if (bytes <= space) { | |
143 | QLIST_INSERT_BEFORE(cur, bounce, next); | |
144 | bounce->buf.iov_base = addr; | |
145 | bounce->buf.iov_len = bytes; | |
146 | return true; | |
147 | } | |
148 | ||
149 | addr = cur->buf.iov_base + cur->buf.iov_len; | |
150 | prev = cur; | |
151 | } | |
152 | ||
153 | /* Is there space after the last request? */ | |
154 | space = s->bounce_pool.addr + s->bounce_pool.len - addr; | |
155 | if (bytes > space) { | |
156 | return false; | |
157 | } | |
158 | if (prev) { | |
159 | QLIST_INSERT_AFTER(prev, bounce, next); | |
160 | } else { | |
161 | QLIST_INSERT_HEAD(&s->bounce_bufs, bounce, next); | |
162 | } | |
163 | bounce->buf.iov_base = addr; | |
164 | bounce->buf.iov_len = bytes; | |
165 | return true; | |
166 | } | |
167 | ||
168 | static int coroutine_fn | |
169 | blkio_alloc_bounce_buffer(BDRVBlkioState *s, BlkioBounceBuf *bounce, | |
170 | int64_t bytes) | |
171 | { | |
172 | /* | |
173 | * Ensure fairness: first time around we join the back of the queue, | |
174 | * subsequently we join the front so we don't lose our place. | |
175 | */ | |
176 | CoQueueWaitFlags wait_flags = 0; | |
177 | ||
178 | QEMU_LOCK_GUARD(&s->bounce_lock); | |
179 | ||
180 | /* Ensure fairness: don't even try if other requests are already waiting */ | |
181 | if (!qemu_co_queue_empty(&s->bounce_available)) { | |
182 | qemu_co_queue_wait_flags(&s->bounce_available, &s->bounce_lock, | |
183 | wait_flags); | |
184 | wait_flags = CO_QUEUE_WAIT_FRONT; | |
185 | } | |
186 | ||
187 | while (true) { | |
188 | if (blkio_do_alloc_bounce_buffer(s, bounce, bytes)) { | |
189 | /* Kick the next queued request since there may be space */ | |
190 | qemu_co_queue_next(&s->bounce_available); | |
191 | return 0; | |
192 | } | |
193 | ||
194 | /* | |
195 | * If there are no in-flight requests then the pool was simply too | |
196 | * small. | |
197 | */ | |
198 | if (QLIST_EMPTY(&s->bounce_bufs)) { | |
199 | bool ok; | |
200 | int ret; | |
201 | ||
202 | ret = blkio_resize_bounce_pool(s, bytes); | |
203 | if (ret < 0) { | |
204 | /* Kick the next queued request since that may fail too */ | |
205 | qemu_co_queue_next(&s->bounce_available); | |
206 | return ret; | |
207 | } | |
208 | ||
209 | ok = blkio_do_alloc_bounce_buffer(s, bounce, bytes); | |
210 | assert(ok); /* must have space this time */ | |
211 | return 0; | |
212 | } | |
213 | ||
214 | qemu_co_queue_wait_flags(&s->bounce_available, &s->bounce_lock, | |
215 | wait_flags); | |
216 | wait_flags = CO_QUEUE_WAIT_FRONT; | |
217 | } | |
218 | } | |
219 | ||
220 | static void coroutine_fn blkio_free_bounce_buffer(BDRVBlkioState *s, | |
221 | BlkioBounceBuf *bounce) | |
222 | { | |
223 | QEMU_LOCK_GUARD(&s->bounce_lock); | |
224 | ||
225 | QLIST_REMOVE(bounce, next); | |
226 | ||
227 | /* Wake up waiting coroutines since space may now be available */ | |
228 | qemu_co_queue_next(&s->bounce_available); | |
229 | } | |
230 | ||
231 | /* For async to .bdrv_co_*() conversion */ | |
232 | typedef struct { | |
233 | Coroutine *coroutine; | |
234 | int ret; | |
235 | } BlkioCoData; | |
236 | ||
237 | static void blkio_completion_fd_read(void *opaque) | |
238 | { | |
239 | BlockDriverState *bs = opaque; | |
240 | BDRVBlkioState *s = bs->opaque; | |
241 | uint64_t val; | |
242 | int ret; | |
243 | ||
244 | /* Polling may have already fetched a completion */ | |
245 | if (s->poll_completion.user_data != NULL) { | |
246 | BlkioCoData *cod = s->poll_completion.user_data; | |
247 | cod->ret = s->poll_completion.ret; | |
248 | ||
249 | /* Clear it in case aio_co_wake() enters a nested event loop */ | |
250 | s->poll_completion.user_data = NULL; | |
251 | ||
252 | aio_co_wake(cod->coroutine); | |
253 | } | |
254 | ||
255 | /* Reset completion fd status */ | |
256 | ret = read(s->completion_fd, &val, sizeof(val)); | |
257 | ||
258 | /* Ignore errors, there's nothing we can do */ | |
259 | (void)ret; | |
260 | ||
261 | /* | |
262 | * Reading one completion at a time makes nested event loop re-entrancy | |
263 | * simple. Change this loop to get multiple completions in one go if it | |
264 | * becomes a performance bottleneck. | |
265 | */ | |
266 | while (true) { | |
267 | struct blkio_completion completion; | |
268 | ||
269 | WITH_QEMU_LOCK_GUARD(&s->blkio_lock) { | |
270 | ret = blkioq_do_io(s->blkioq, &completion, 0, 1, NULL); | |
271 | } | |
272 | if (ret != 1) { | |
273 | break; | |
274 | } | |
275 | ||
276 | BlkioCoData *cod = completion.user_data; | |
277 | cod->ret = completion.ret; | |
278 | aio_co_wake(cod->coroutine); | |
279 | } | |
280 | } | |
281 | ||
282 | static bool blkio_completion_fd_poll(void *opaque) | |
283 | { | |
284 | BlockDriverState *bs = opaque; | |
285 | BDRVBlkioState *s = bs->opaque; | |
286 | int ret; | |
287 | ||
288 | /* Just in case we already fetched a completion */ | |
289 | if (s->poll_completion.user_data != NULL) { | |
290 | return true; | |
291 | } | |
292 | ||
293 | WITH_QEMU_LOCK_GUARD(&s->blkio_lock) { | |
294 | ret = blkioq_do_io(s->blkioq, &s->poll_completion, 0, 1, NULL); | |
295 | } | |
296 | return ret == 1; | |
297 | } | |
298 | ||
299 | static void blkio_completion_fd_poll_ready(void *opaque) | |
300 | { | |
301 | blkio_completion_fd_read(opaque); | |
302 | } | |
303 | ||
304 | static void blkio_attach_aio_context(BlockDriverState *bs, | |
305 | AioContext *new_context) | |
306 | { | |
307 | BDRVBlkioState *s = bs->opaque; | |
308 | ||
309 | aio_set_fd_handler(new_context, | |
310 | s->completion_fd, | |
311 | false, | |
312 | blkio_completion_fd_read, | |
313 | NULL, | |
314 | blkio_completion_fd_poll, | |
315 | blkio_completion_fd_poll_ready, | |
316 | bs); | |
317 | } | |
318 | ||
319 | static void blkio_detach_aio_context(BlockDriverState *bs) | |
320 | { | |
321 | BDRVBlkioState *s = bs->opaque; | |
322 | ||
323 | aio_set_fd_handler(bdrv_get_aio_context(bs), | |
324 | s->completion_fd, | |
325 | false, NULL, NULL, NULL, NULL, NULL); | |
326 | } | |
327 | ||
328 | /* Call with s->blkio_lock held to submit I/O after enqueuing a new request */ | |
329 | static void blkio_submit_io(BlockDriverState *bs) | |
330 | { | |
331 | if (qatomic_read(&bs->io_plugged) == 0) { | |
332 | BDRVBlkioState *s = bs->opaque; | |
333 | ||
334 | blkioq_do_io(s->blkioq, NULL, 0, 0, NULL); | |
335 | } | |
336 | } | |
337 | ||
338 | static int coroutine_fn | |
339 | blkio_co_pdiscard(BlockDriverState *bs, int64_t offset, int64_t bytes) | |
340 | { | |
341 | BDRVBlkioState *s = bs->opaque; | |
342 | BlkioCoData cod = { | |
343 | .coroutine = qemu_coroutine_self(), | |
344 | }; | |
345 | ||
346 | WITH_QEMU_LOCK_GUARD(&s->blkio_lock) { | |
347 | blkioq_discard(s->blkioq, offset, bytes, &cod, 0); | |
348 | blkio_submit_io(bs); | |
349 | } | |
350 | ||
351 | qemu_coroutine_yield(); | |
352 | return cod.ret; | |
353 | } | |
354 | ||
355 | static int coroutine_fn | |
356 | blkio_co_preadv(BlockDriverState *bs, int64_t offset, int64_t bytes, | |
357 | QEMUIOVector *qiov, BdrvRequestFlags flags) | |
358 | { | |
359 | BlkioCoData cod = { | |
360 | .coroutine = qemu_coroutine_self(), | |
361 | }; | |
362 | BDRVBlkioState *s = bs->opaque; | |
c5640b3e SH |
363 | bool use_bounce_buffer = |
364 | s->needs_mem_regions && !(flags & BDRV_REQ_REGISTERED_BUF); | |
fd66dbd4 SH |
365 | BlkioBounceBuf bounce; |
366 | struct iovec *iov = qiov->iov; | |
367 | int iovcnt = qiov->niov; | |
368 | ||
369 | if (use_bounce_buffer) { | |
370 | int ret = blkio_alloc_bounce_buffer(s, &bounce, bytes); | |
371 | if (ret < 0) { | |
372 | return ret; | |
373 | } | |
374 | ||
375 | iov = &bounce.buf; | |
376 | iovcnt = 1; | |
377 | } | |
378 | ||
379 | WITH_QEMU_LOCK_GUARD(&s->blkio_lock) { | |
380 | blkioq_readv(s->blkioq, offset, iov, iovcnt, &cod, 0); | |
381 | blkio_submit_io(bs); | |
382 | } | |
383 | ||
384 | qemu_coroutine_yield(); | |
385 | ||
386 | if (use_bounce_buffer) { | |
387 | if (cod.ret == 0) { | |
388 | qemu_iovec_from_buf(qiov, 0, | |
389 | bounce.buf.iov_base, | |
390 | bounce.buf.iov_len); | |
391 | } | |
392 | ||
393 | blkio_free_bounce_buffer(s, &bounce); | |
394 | } | |
395 | ||
396 | return cod.ret; | |
397 | } | |
398 | ||
399 | static int coroutine_fn blkio_co_pwritev(BlockDriverState *bs, int64_t offset, | |
400 | int64_t bytes, QEMUIOVector *qiov, BdrvRequestFlags flags) | |
401 | { | |
402 | uint32_t blkio_flags = (flags & BDRV_REQ_FUA) ? BLKIO_REQ_FUA : 0; | |
403 | BlkioCoData cod = { | |
404 | .coroutine = qemu_coroutine_self(), | |
405 | }; | |
406 | BDRVBlkioState *s = bs->opaque; | |
c5640b3e SH |
407 | bool use_bounce_buffer = |
408 | s->needs_mem_regions && !(flags & BDRV_REQ_REGISTERED_BUF); | |
fd66dbd4 SH |
409 | BlkioBounceBuf bounce; |
410 | struct iovec *iov = qiov->iov; | |
411 | int iovcnt = qiov->niov; | |
412 | ||
413 | if (use_bounce_buffer) { | |
414 | int ret = blkio_alloc_bounce_buffer(s, &bounce, bytes); | |
415 | if (ret < 0) { | |
416 | return ret; | |
417 | } | |
418 | ||
419 | qemu_iovec_to_buf(qiov, 0, bounce.buf.iov_base, bytes); | |
420 | iov = &bounce.buf; | |
421 | iovcnt = 1; | |
422 | } | |
423 | ||
424 | WITH_QEMU_LOCK_GUARD(&s->blkio_lock) { | |
425 | blkioq_writev(s->blkioq, offset, iov, iovcnt, &cod, blkio_flags); | |
426 | blkio_submit_io(bs); | |
427 | } | |
428 | ||
429 | qemu_coroutine_yield(); | |
430 | ||
431 | if (use_bounce_buffer) { | |
432 | blkio_free_bounce_buffer(s, &bounce); | |
433 | } | |
434 | ||
435 | return cod.ret; | |
436 | } | |
437 | ||
438 | static int coroutine_fn blkio_co_flush(BlockDriverState *bs) | |
439 | { | |
440 | BDRVBlkioState *s = bs->opaque; | |
441 | BlkioCoData cod = { | |
442 | .coroutine = qemu_coroutine_self(), | |
443 | }; | |
444 | ||
445 | WITH_QEMU_LOCK_GUARD(&s->blkio_lock) { | |
446 | blkioq_flush(s->blkioq, &cod, 0); | |
447 | blkio_submit_io(bs); | |
448 | } | |
449 | ||
450 | qemu_coroutine_yield(); | |
451 | return cod.ret; | |
452 | } | |
453 | ||
454 | static int coroutine_fn blkio_co_pwrite_zeroes(BlockDriverState *bs, | |
455 | int64_t offset, int64_t bytes, BdrvRequestFlags flags) | |
456 | { | |
457 | BDRVBlkioState *s = bs->opaque; | |
458 | BlkioCoData cod = { | |
459 | .coroutine = qemu_coroutine_self(), | |
460 | }; | |
461 | uint32_t blkio_flags = 0; | |
462 | ||
463 | if (flags & BDRV_REQ_FUA) { | |
464 | blkio_flags |= BLKIO_REQ_FUA; | |
465 | } | |
466 | if (!(flags & BDRV_REQ_MAY_UNMAP)) { | |
467 | blkio_flags |= BLKIO_REQ_NO_UNMAP; | |
468 | } | |
469 | if (flags & BDRV_REQ_NO_FALLBACK) { | |
470 | blkio_flags |= BLKIO_REQ_NO_FALLBACK; | |
471 | } | |
472 | ||
473 | WITH_QEMU_LOCK_GUARD(&s->blkio_lock) { | |
474 | blkioq_write_zeroes(s->blkioq, offset, bytes, &cod, blkio_flags); | |
475 | blkio_submit_io(bs); | |
476 | } | |
477 | ||
478 | qemu_coroutine_yield(); | |
479 | return cod.ret; | |
480 | } | |
481 | ||
09d9fc97 | 482 | static void coroutine_fn blkio_co_io_unplug(BlockDriverState *bs) |
fd66dbd4 SH |
483 | { |
484 | BDRVBlkioState *s = bs->opaque; | |
485 | ||
486 | WITH_QEMU_LOCK_GUARD(&s->blkio_lock) { | |
487 | blkio_submit_io(bs); | |
488 | } | |
489 | } | |
490 | ||
c5640b3e SH |
491 | typedef enum { |
492 | BMRR_OK, | |
493 | BMRR_SKIP, | |
494 | BMRR_FAIL, | |
495 | } BlkioMemRegionResult; | |
496 | ||
497 | /* | |
498 | * Produce a struct blkio_mem_region for a given address and size. | |
499 | * | |
500 | * This function produces identical results when called multiple times with the | |
501 | * same arguments. This property is necessary because blkio_unmap_mem_region() | |
502 | * must receive the same struct blkio_mem_region field values that were passed | |
503 | * to blkio_map_mem_region(). | |
504 | */ | |
505 | static BlkioMemRegionResult | |
506 | blkio_mem_region_from_host(BlockDriverState *bs, | |
507 | void *host, size_t size, | |
508 | struct blkio_mem_region *region, | |
509 | Error **errp) | |
510 | { | |
511 | BDRVBlkioState *s = bs->opaque; | |
512 | int fd = -1; | |
513 | ram_addr_t fd_offset = 0; | |
514 | ||
515 | if (((uintptr_t)host | size) % s->mem_region_alignment) { | |
516 | error_setg(errp, "unaligned buf %p with size %zu", host, size); | |
517 | return BMRR_FAIL; | |
518 | } | |
519 | ||
520 | /* Attempt to find the fd for the underlying memory */ | |
521 | if (s->needs_mem_region_fd) { | |
522 | RAMBlock *ram_block; | |
523 | RAMBlock *end_block; | |
524 | ram_addr_t offset; | |
525 | ||
526 | /* | |
527 | * bdrv_register_buf() is called with the BQL held so mr lives at least | |
528 | * until this function returns. | |
529 | */ | |
530 | ram_block = qemu_ram_block_from_host(host, false, &fd_offset); | |
531 | if (ram_block) { | |
532 | fd = qemu_ram_get_fd(ram_block); | |
533 | } | |
534 | if (fd == -1) { | |
535 | /* | |
536 | * Ideally every RAMBlock would have an fd. pc-bios and other | |
537 | * things don't. Luckily they are usually not I/O buffers and we | |
538 | * can just ignore them. | |
539 | */ | |
540 | return BMRR_SKIP; | |
541 | } | |
542 | ||
543 | /* Make sure the fd covers the entire range */ | |
544 | end_block = qemu_ram_block_from_host(host + size - 1, false, &offset); | |
545 | if (ram_block != end_block) { | |
546 | error_setg(errp, "registered buffer at %p with size %zu extends " | |
547 | "beyond RAMBlock", host, size); | |
548 | return BMRR_FAIL; | |
549 | } | |
550 | } | |
551 | ||
552 | *region = (struct blkio_mem_region){ | |
553 | .addr = host, | |
554 | .len = size, | |
555 | .fd = fd, | |
556 | .fd_offset = fd_offset, | |
557 | }; | |
558 | return BMRR_OK; | |
559 | } | |
560 | ||
561 | static bool blkio_register_buf(BlockDriverState *bs, void *host, size_t size, | |
562 | Error **errp) | |
563 | { | |
564 | BDRVBlkioState *s = bs->opaque; | |
565 | struct blkio_mem_region region; | |
566 | BlkioMemRegionResult region_result; | |
567 | int ret; | |
568 | ||
569 | /* | |
570 | * Mapping memory regions conflicts with RAM discard (virtio-mem) when | |
571 | * there is pinning, so only do it when necessary. | |
572 | */ | |
573 | if (!s->needs_mem_regions && s->may_pin_mem_regions) { | |
574 | return true; | |
575 | } | |
576 | ||
577 | region_result = blkio_mem_region_from_host(bs, host, size, ®ion, errp); | |
578 | if (region_result == BMRR_SKIP) { | |
579 | return true; | |
580 | } else if (region_result != BMRR_OK) { | |
581 | return false; | |
582 | } | |
583 | ||
584 | WITH_QEMU_LOCK_GUARD(&s->blkio_lock) { | |
585 | ret = blkio_map_mem_region(s->blkio, ®ion); | |
586 | } | |
587 | ||
588 | if (ret < 0) { | |
589 | error_setg(errp, "Failed to add blkio mem region %p with size %zu: %s", | |
590 | host, size, blkio_get_error_msg()); | |
591 | return false; | |
592 | } | |
593 | return true; | |
594 | } | |
595 | ||
596 | static void blkio_unregister_buf(BlockDriverState *bs, void *host, size_t size) | |
597 | { | |
598 | BDRVBlkioState *s = bs->opaque; | |
599 | struct blkio_mem_region region; | |
600 | ||
601 | /* See blkio_register_buf() */ | |
602 | if (!s->needs_mem_regions && s->may_pin_mem_regions) { | |
603 | return; | |
604 | } | |
605 | ||
606 | if (blkio_mem_region_from_host(bs, host, size, ®ion, NULL) != BMRR_OK) { | |
607 | return; | |
608 | } | |
609 | ||
610 | WITH_QEMU_LOCK_GUARD(&s->blkio_lock) { | |
611 | blkio_unmap_mem_region(s->blkio, ®ion); | |
612 | } | |
613 | } | |
614 | ||
fd66dbd4 SH |
615 | static int blkio_io_uring_open(BlockDriverState *bs, QDict *options, int flags, |
616 | Error **errp) | |
617 | { | |
618 | const char *filename = qdict_get_str(options, "filename"); | |
619 | BDRVBlkioState *s = bs->opaque; | |
620 | int ret; | |
621 | ||
622 | ret = blkio_set_str(s->blkio, "path", filename); | |
623 | qdict_del(options, "filename"); | |
624 | if (ret < 0) { | |
625 | error_setg_errno(errp, -ret, "failed to set path: %s", | |
626 | blkio_get_error_msg()); | |
627 | return ret; | |
628 | } | |
629 | ||
630 | if (flags & BDRV_O_NOCACHE) { | |
631 | ret = blkio_set_bool(s->blkio, "direct", true); | |
632 | if (ret < 0) { | |
633 | error_setg_errno(errp, -ret, "failed to set direct: %s", | |
634 | blkio_get_error_msg()); | |
635 | return ret; | |
636 | } | |
637 | } | |
638 | ||
639 | return 0; | |
640 | } | |
641 | ||
642 | static int blkio_nvme_io_uring(BlockDriverState *bs, QDict *options, int flags, | |
643 | Error **errp) | |
644 | { | |
6c32fc0d | 645 | const char *path = qdict_get_try_str(options, "path"); |
fd66dbd4 SH |
646 | BDRVBlkioState *s = bs->opaque; |
647 | int ret; | |
648 | ||
6c32fc0d AF |
649 | if (!path) { |
650 | error_setg(errp, "missing 'path' option"); | |
651 | return -EINVAL; | |
652 | } | |
653 | ||
654 | ret = blkio_set_str(s->blkio, "path", path); | |
655 | qdict_del(options, "path"); | |
fd66dbd4 SH |
656 | if (ret < 0) { |
657 | error_setg_errno(errp, -ret, "failed to set path: %s", | |
658 | blkio_get_error_msg()); | |
659 | return ret; | |
660 | } | |
661 | ||
662 | if (!(flags & BDRV_O_NOCACHE)) { | |
663 | error_setg(errp, "cache.direct=off is not supported"); | |
664 | return -EINVAL; | |
665 | } | |
666 | ||
667 | return 0; | |
668 | } | |
669 | ||
670 | static int blkio_virtio_blk_common_open(BlockDriverState *bs, | |
671 | QDict *options, int flags, Error **errp) | |
672 | { | |
673 | const char *path = qdict_get_try_str(options, "path"); | |
674 | BDRVBlkioState *s = bs->opaque; | |
675 | int ret; | |
676 | ||
677 | if (!path) { | |
678 | error_setg(errp, "missing 'path' option"); | |
679 | return -EINVAL; | |
680 | } | |
681 | ||
682 | ret = blkio_set_str(s->blkio, "path", path); | |
683 | qdict_del(options, "path"); | |
684 | if (ret < 0) { | |
685 | error_setg_errno(errp, -ret, "failed to set path: %s", | |
686 | blkio_get_error_msg()); | |
687 | return ret; | |
688 | } | |
689 | ||
690 | if (!(flags & BDRV_O_NOCACHE)) { | |
691 | error_setg(errp, "cache.direct=off is not supported"); | |
692 | return -EINVAL; | |
693 | } | |
694 | return 0; | |
695 | } | |
696 | ||
697 | static int blkio_file_open(BlockDriverState *bs, QDict *options, int flags, | |
698 | Error **errp) | |
699 | { | |
700 | const char *blkio_driver = bs->drv->protocol_name; | |
701 | BDRVBlkioState *s = bs->opaque; | |
702 | int ret; | |
703 | ||
704 | ret = blkio_create(blkio_driver, &s->blkio); | |
705 | if (ret < 0) { | |
706 | error_setg_errno(errp, -ret, "blkio_create failed: %s", | |
707 | blkio_get_error_msg()); | |
708 | return ret; | |
709 | } | |
710 | ||
711 | if (strcmp(blkio_driver, DRIVER_IO_URING) == 0) { | |
712 | ret = blkio_io_uring_open(bs, options, flags, errp); | |
713 | } else if (strcmp(blkio_driver, DRIVER_NVME_IO_URING) == 0) { | |
714 | ret = blkio_nvme_io_uring(bs, options, flags, errp); | |
03d9e4c0 AF |
715 | } else if (strcmp(blkio_driver, DRIVER_VIRTIO_BLK_VFIO_PCI) == 0) { |
716 | ret = blkio_virtio_blk_common_open(bs, options, flags, errp); | |
fd66dbd4 SH |
717 | } else if (strcmp(blkio_driver, DRIVER_VIRTIO_BLK_VHOST_USER) == 0) { |
718 | ret = blkio_virtio_blk_common_open(bs, options, flags, errp); | |
719 | } else if (strcmp(blkio_driver, DRIVER_VIRTIO_BLK_VHOST_VDPA) == 0) { | |
720 | ret = blkio_virtio_blk_common_open(bs, options, flags, errp); | |
721 | } else { | |
722 | g_assert_not_reached(); | |
723 | } | |
724 | if (ret < 0) { | |
725 | blkio_destroy(&s->blkio); | |
726 | return ret; | |
727 | } | |
728 | ||
729 | if (!(flags & BDRV_O_RDWR)) { | |
730 | ret = blkio_set_bool(s->blkio, "read-only", true); | |
731 | if (ret < 0) { | |
732 | error_setg_errno(errp, -ret, "failed to set read-only: %s", | |
733 | blkio_get_error_msg()); | |
734 | blkio_destroy(&s->blkio); | |
735 | return ret; | |
736 | } | |
737 | } | |
738 | ||
739 | ret = blkio_connect(s->blkio); | |
740 | if (ret < 0) { | |
741 | error_setg_errno(errp, -ret, "blkio_connect failed: %s", | |
742 | blkio_get_error_msg()); | |
743 | blkio_destroy(&s->blkio); | |
744 | return ret; | |
745 | } | |
746 | ||
747 | ret = blkio_get_bool(s->blkio, | |
748 | "needs-mem-regions", | |
749 | &s->needs_mem_regions); | |
750 | if (ret < 0) { | |
751 | error_setg_errno(errp, -ret, | |
752 | "failed to get needs-mem-regions: %s", | |
753 | blkio_get_error_msg()); | |
754 | blkio_destroy(&s->blkio); | |
755 | return ret; | |
756 | } | |
757 | ||
c5640b3e SH |
758 | ret = blkio_get_bool(s->blkio, |
759 | "needs-mem-region-fd", | |
760 | &s->needs_mem_region_fd); | |
761 | if (ret < 0) { | |
762 | error_setg_errno(errp, -ret, | |
763 | "failed to get needs-mem-region-fd: %s", | |
764 | blkio_get_error_msg()); | |
765 | blkio_destroy(&s->blkio); | |
766 | return ret; | |
767 | } | |
768 | ||
fd66dbd4 SH |
769 | ret = blkio_get_uint64(s->blkio, |
770 | "mem-region-alignment", | |
771 | &s->mem_region_alignment); | |
772 | if (ret < 0) { | |
773 | error_setg_errno(errp, -ret, | |
774 | "failed to get mem-region-alignment: %s", | |
775 | blkio_get_error_msg()); | |
776 | blkio_destroy(&s->blkio); | |
777 | return ret; | |
778 | } | |
779 | ||
c5640b3e SH |
780 | ret = blkio_get_bool(s->blkio, |
781 | "may-pin-mem-regions", | |
782 | &s->may_pin_mem_regions); | |
783 | if (ret < 0) { | |
784 | /* Be conservative (assume pinning) if the property is not supported */ | |
785 | s->may_pin_mem_regions = s->needs_mem_regions; | |
786 | } | |
787 | ||
788 | /* | |
789 | * Notify if libblkio drivers pin memory and prevent features like | |
790 | * virtio-mem from working. | |
791 | */ | |
792 | if (s->may_pin_mem_regions) { | |
793 | ret = ram_block_discard_disable(true); | |
794 | if (ret < 0) { | |
795 | error_setg_errno(errp, -ret, "ram_block_discard_disable() failed"); | |
796 | blkio_destroy(&s->blkio); | |
797 | return ret; | |
798 | } | |
799 | } | |
800 | ||
fd66dbd4 SH |
801 | ret = blkio_start(s->blkio); |
802 | if (ret < 0) { | |
803 | error_setg_errno(errp, -ret, "blkio_start failed: %s", | |
804 | blkio_get_error_msg()); | |
805 | blkio_destroy(&s->blkio); | |
c5640b3e SH |
806 | if (s->may_pin_mem_regions) { |
807 | ram_block_discard_disable(false); | |
808 | } | |
fd66dbd4 SH |
809 | return ret; |
810 | } | |
811 | ||
c5640b3e | 812 | bs->supported_write_flags = BDRV_REQ_FUA | BDRV_REQ_REGISTERED_BUF; |
fd66dbd4 SH |
813 | bs->supported_zero_flags = BDRV_REQ_FUA | BDRV_REQ_MAY_UNMAP | |
814 | BDRV_REQ_NO_FALLBACK; | |
815 | ||
816 | qemu_mutex_init(&s->blkio_lock); | |
817 | qemu_co_mutex_init(&s->bounce_lock); | |
818 | qemu_co_queue_init(&s->bounce_available); | |
819 | QLIST_INIT(&s->bounce_bufs); | |
820 | s->blkioq = blkio_get_queue(s->blkio, 0); | |
821 | s->completion_fd = blkioq_get_completion_fd(s->blkioq); | |
822 | ||
823 | blkio_attach_aio_context(bs, bdrv_get_aio_context(bs)); | |
824 | return 0; | |
825 | } | |
826 | ||
827 | static void blkio_close(BlockDriverState *bs) | |
828 | { | |
829 | BDRVBlkioState *s = bs->opaque; | |
830 | ||
831 | /* There is no destroy() API for s->bounce_lock */ | |
832 | ||
833 | qemu_mutex_destroy(&s->blkio_lock); | |
834 | blkio_detach_aio_context(bs); | |
835 | blkio_destroy(&s->blkio); | |
c5640b3e SH |
836 | |
837 | if (s->may_pin_mem_regions) { | |
838 | ram_block_discard_disable(false); | |
839 | } | |
fd66dbd4 SH |
840 | } |
841 | ||
c86422c5 | 842 | static int64_t coroutine_fn blkio_co_getlength(BlockDriverState *bs) |
fd66dbd4 SH |
843 | { |
844 | BDRVBlkioState *s = bs->opaque; | |
845 | uint64_t capacity; | |
846 | int ret; | |
847 | ||
848 | WITH_QEMU_LOCK_GUARD(&s->blkio_lock) { | |
849 | ret = blkio_get_uint64(s->blkio, "capacity", &capacity); | |
850 | } | |
851 | if (ret < 0) { | |
852 | return -ret; | |
853 | } | |
854 | ||
855 | return capacity; | |
856 | } | |
857 | ||
4c8f4fda AF |
858 | static int coroutine_fn blkio_truncate(BlockDriverState *bs, int64_t offset, |
859 | bool exact, PreallocMode prealloc, | |
860 | BdrvRequestFlags flags, Error **errp) | |
861 | { | |
862 | int64_t current_length; | |
863 | ||
864 | if (prealloc != PREALLOC_MODE_OFF) { | |
865 | error_setg(errp, "Unsupported preallocation mode '%s'", | |
866 | PreallocMode_str(prealloc)); | |
867 | return -ENOTSUP; | |
868 | } | |
869 | ||
c86422c5 | 870 | current_length = blkio_co_getlength(bs); |
4c8f4fda AF |
871 | |
872 | if (offset > current_length) { | |
873 | error_setg(errp, "Cannot grow device"); | |
874 | return -EINVAL; | |
875 | } else if (exact && offset != current_length) { | |
876 | error_setg(errp, "Cannot resize device"); | |
877 | return -ENOTSUP; | |
878 | } | |
879 | ||
880 | return 0; | |
881 | } | |
882 | ||
fd66dbd4 SH |
883 | static int blkio_get_info(BlockDriverState *bs, BlockDriverInfo *bdi) |
884 | { | |
885 | return 0; | |
886 | } | |
887 | ||
888 | static void blkio_refresh_limits(BlockDriverState *bs, Error **errp) | |
889 | { | |
890 | BDRVBlkioState *s = bs->opaque; | |
891 | QEMU_LOCK_GUARD(&s->blkio_lock); | |
892 | int value; | |
893 | int ret; | |
894 | ||
895 | ret = blkio_get_int(s->blkio, "request-alignment", &value); | |
896 | if (ret < 0) { | |
897 | error_setg_errno(errp, -ret, "failed to get \"request-alignment\": %s", | |
898 | blkio_get_error_msg()); | |
899 | return; | |
900 | } | |
901 | bs->bl.request_alignment = value; | |
902 | if (bs->bl.request_alignment < 1 || | |
903 | bs->bl.request_alignment >= INT_MAX || | |
904 | !is_power_of_2(bs->bl.request_alignment)) { | |
905 | error_setg(errp, "invalid \"request-alignment\" value %" PRIu32 ", " | |
906 | "must be a power of 2 less than INT_MAX", | |
907 | bs->bl.request_alignment); | |
908 | return; | |
909 | } | |
910 | ||
911 | ret = blkio_get_int(s->blkio, "optimal-io-size", &value); | |
912 | if (ret < 0) { | |
913 | error_setg_errno(errp, -ret, "failed to get \"optimal-io-size\": %s", | |
914 | blkio_get_error_msg()); | |
915 | return; | |
916 | } | |
917 | bs->bl.opt_transfer = value; | |
918 | if (bs->bl.opt_transfer > INT_MAX || | |
919 | (bs->bl.opt_transfer % bs->bl.request_alignment)) { | |
920 | error_setg(errp, "invalid \"optimal-io-size\" value %" PRIu32 ", must " | |
921 | "be a multiple of %" PRIu32, bs->bl.opt_transfer, | |
922 | bs->bl.request_alignment); | |
923 | return; | |
924 | } | |
925 | ||
926 | ret = blkio_get_int(s->blkio, "max-transfer", &value); | |
927 | if (ret < 0) { | |
928 | error_setg_errno(errp, -ret, "failed to get \"max-transfer\": %s", | |
929 | blkio_get_error_msg()); | |
930 | return; | |
931 | } | |
932 | bs->bl.max_transfer = value; | |
933 | if ((bs->bl.max_transfer % bs->bl.request_alignment) || | |
934 | (bs->bl.opt_transfer && (bs->bl.max_transfer % bs->bl.opt_transfer))) { | |
935 | error_setg(errp, "invalid \"max-transfer\" value %" PRIu32 ", must be " | |
936 | "a multiple of %" PRIu32 " and %" PRIu32 " (if non-zero)", | |
937 | bs->bl.max_transfer, bs->bl.request_alignment, | |
938 | bs->bl.opt_transfer); | |
939 | return; | |
940 | } | |
941 | ||
942 | ret = blkio_get_int(s->blkio, "buf-alignment", &value); | |
943 | if (ret < 0) { | |
944 | error_setg_errno(errp, -ret, "failed to get \"buf-alignment\": %s", | |
945 | blkio_get_error_msg()); | |
946 | return; | |
947 | } | |
948 | if (value < 1) { | |
949 | error_setg(errp, "invalid \"buf-alignment\" value %d, must be " | |
950 | "positive", value); | |
951 | return; | |
952 | } | |
953 | bs->bl.min_mem_alignment = value; | |
954 | ||
955 | ret = blkio_get_int(s->blkio, "optimal-buf-alignment", &value); | |
956 | if (ret < 0) { | |
957 | error_setg_errno(errp, -ret, | |
958 | "failed to get \"optimal-buf-alignment\": %s", | |
959 | blkio_get_error_msg()); | |
960 | return; | |
961 | } | |
962 | if (value < 1) { | |
963 | error_setg(errp, "invalid \"optimal-buf-alignment\" value %d, " | |
964 | "must be positive", value); | |
965 | return; | |
966 | } | |
967 | bs->bl.opt_mem_alignment = value; | |
968 | ||
969 | ret = blkio_get_int(s->blkio, "max-segments", &value); | |
970 | if (ret < 0) { | |
971 | error_setg_errno(errp, -ret, "failed to get \"max-segments\": %s", | |
972 | blkio_get_error_msg()); | |
973 | return; | |
974 | } | |
975 | if (value < 1) { | |
976 | error_setg(errp, "invalid \"max-segments\" value %d, must be positive", | |
977 | value); | |
978 | return; | |
979 | } | |
980 | bs->bl.max_iov = value; | |
981 | } | |
982 | ||
983 | /* | |
984 | * TODO | |
985 | * Missing libblkio APIs: | |
986 | * - block_status | |
987 | * - co_invalidate_cache | |
988 | * | |
989 | * Out of scope? | |
990 | * - create | |
991 | * - truncate | |
992 | */ | |
993 | ||
994 | #define BLKIO_DRIVER(name, ...) \ | |
995 | { \ | |
996 | .format_name = name, \ | |
997 | .protocol_name = name, \ | |
998 | .instance_size = sizeof(BDRVBlkioState), \ | |
999 | .bdrv_file_open = blkio_file_open, \ | |
1000 | .bdrv_close = blkio_close, \ | |
c86422c5 | 1001 | .bdrv_co_getlength = blkio_co_getlength, \ |
4c8f4fda | 1002 | .bdrv_co_truncate = blkio_truncate, \ |
fd66dbd4 SH |
1003 | .bdrv_get_info = blkio_get_info, \ |
1004 | .bdrv_attach_aio_context = blkio_attach_aio_context, \ | |
1005 | .bdrv_detach_aio_context = blkio_detach_aio_context, \ | |
1006 | .bdrv_co_pdiscard = blkio_co_pdiscard, \ | |
1007 | .bdrv_co_preadv = blkio_co_preadv, \ | |
1008 | .bdrv_co_pwritev = blkio_co_pwritev, \ | |
1009 | .bdrv_co_flush_to_disk = blkio_co_flush, \ | |
1010 | .bdrv_co_pwrite_zeroes = blkio_co_pwrite_zeroes, \ | |
09d9fc97 | 1011 | .bdrv_co_io_unplug = blkio_co_io_unplug, \ |
fd66dbd4 | 1012 | .bdrv_refresh_limits = blkio_refresh_limits, \ |
c5640b3e SH |
1013 | .bdrv_register_buf = blkio_register_buf, \ |
1014 | .bdrv_unregister_buf = blkio_unregister_buf, \ | |
fd66dbd4 SH |
1015 | __VA_ARGS__ \ |
1016 | } | |
1017 | ||
1018 | static BlockDriver bdrv_io_uring = BLKIO_DRIVER( | |
1019 | DRIVER_IO_URING, | |
1020 | .bdrv_needs_filename = true, | |
1021 | ); | |
1022 | ||
1023 | static BlockDriver bdrv_nvme_io_uring = BLKIO_DRIVER( | |
1024 | DRIVER_NVME_IO_URING, | |
fd66dbd4 SH |
1025 | ); |
1026 | ||
03d9e4c0 AF |
1027 | static BlockDriver bdrv_virtio_blk_vfio_pci = BLKIO_DRIVER( |
1028 | DRIVER_VIRTIO_BLK_VFIO_PCI | |
1029 | ); | |
1030 | ||
fd66dbd4 SH |
1031 | static BlockDriver bdrv_virtio_blk_vhost_user = BLKIO_DRIVER( |
1032 | DRIVER_VIRTIO_BLK_VHOST_USER | |
1033 | ); | |
1034 | ||
1035 | static BlockDriver bdrv_virtio_blk_vhost_vdpa = BLKIO_DRIVER( | |
1036 | DRIVER_VIRTIO_BLK_VHOST_VDPA | |
1037 | ); | |
1038 | ||
1039 | static void bdrv_blkio_init(void) | |
1040 | { | |
1041 | bdrv_register(&bdrv_io_uring); | |
1042 | bdrv_register(&bdrv_nvme_io_uring); | |
03d9e4c0 | 1043 | bdrv_register(&bdrv_virtio_blk_vfio_pci); |
fd66dbd4 SH |
1044 | bdrv_register(&bdrv_virtio_blk_vhost_user); |
1045 | bdrv_register(&bdrv_virtio_blk_vhost_vdpa); | |
1046 | } | |
1047 | ||
1048 | block_init(bdrv_blkio_init); |