qapi: Fix malformed "Since:" section tags (again)
[qemu/armbru.git] / block / raw-format.c
blobac7e8495f66ceb4b5d0879747365cca1b4face97
1 /* BlockDriver implementation for "raw" format driver
3 * Copyright (C) 2010-2016 Red Hat, Inc.
4 * Copyright (C) 2010, Blue Swirl <blauwirbel@gmail.com>
5 * Copyright (C) 2009, Anthony Liguori <aliguori@us.ibm.com>
7 * Author:
8 * Laszlo Ersek <lersek@redhat.com>
10 * Permission is hereby granted, free of charge, to any person obtaining a copy
11 * of this software and associated documentation files (the "Software"), to
12 * deal in the Software without restriction, including without limitation the
13 * rights to use, copy, modify, merge, publish, distribute, sublicense, and/or
14 * sell copies of the Software, and to permit persons to whom the Software is
15 * furnished to do so, subject to the following conditions:
17 * The above copyright notice and this permission notice shall be included in
18 * all copies or substantial portions of the Software.
20 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
21 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
22 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
23 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
24 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
25 * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
26 * IN THE SOFTWARE.
29 #include "qemu/osdep.h"
30 #include "block/block-io.h"
31 #include "block/block_int.h"
32 #include "qapi/error.h"
33 #include "qemu/module.h"
34 #include "qemu/option.h"
35 #include "qemu/memalign.h"
37 typedef struct BDRVRawState {
38 uint64_t offset;
39 uint64_t size;
40 bool has_size;
41 } BDRVRawState;
43 static const char *const mutable_opts[] = { "offset", "size", NULL };
45 static QemuOptsList raw_runtime_opts = {
46 .name = "raw",
47 .head = QTAILQ_HEAD_INITIALIZER(raw_runtime_opts.head),
48 .desc = {
50 .name = "offset",
51 .type = QEMU_OPT_SIZE,
52 .help = "offset in the disk where the image starts",
55 .name = "size",
56 .type = QEMU_OPT_SIZE,
57 .help = "virtual disk size",
59 { /* end of list */ }
63 static QemuOptsList raw_create_opts = {
64 .name = "raw-create-opts",
65 .head = QTAILQ_HEAD_INITIALIZER(raw_create_opts.head),
66 .desc = {
68 .name = BLOCK_OPT_SIZE,
69 .type = QEMU_OPT_SIZE,
70 .help = "Virtual disk size"
72 { /* end of list */ }
76 static int raw_read_options(QDict *options, uint64_t *offset, bool *has_size,
77 uint64_t *size, Error **errp)
79 QemuOpts *opts = NULL;
80 int ret;
82 opts = qemu_opts_create(&raw_runtime_opts, NULL, 0, &error_abort);
83 if (!qemu_opts_absorb_qdict(opts, options, errp)) {
84 ret = -EINVAL;
85 goto end;
88 *offset = qemu_opt_get_size(opts, "offset", 0);
89 *has_size = qemu_opt_find(opts, "size");
90 *size = qemu_opt_get_size(opts, "size", 0);
92 ret = 0;
93 end:
94 qemu_opts_del(opts);
95 return ret;
98 static int GRAPH_RDLOCK
99 raw_apply_options(BlockDriverState *bs, BDRVRawState *s, uint64_t offset,
100 bool has_size, uint64_t size, Error **errp)
102 int64_t real_size = 0;
104 real_size = bdrv_getlength(bs->file->bs);
105 if (real_size < 0) {
106 error_setg_errno(errp, -real_size, "Could not get image size");
107 return real_size;
110 /* Check size and offset */
111 if (offset > real_size) {
112 error_setg(errp, "Offset (%" PRIu64 ") cannot be greater than "
113 "size of the containing file (%" PRId64 ")",
114 s->offset, real_size);
115 return -EINVAL;
118 if (has_size && (real_size - offset) < size) {
119 error_setg(errp, "The sum of offset (%" PRIu64 ") and size "
120 "(%" PRIu64 ") has to be smaller or equal to the "
121 " actual size of the containing file (%" PRId64 ")",
122 s->offset, s->size, real_size);
123 return -EINVAL;
126 /* Make sure size is multiple of BDRV_SECTOR_SIZE to prevent rounding
127 * up and leaking out of the specified area. */
128 if (has_size && !QEMU_IS_ALIGNED(size, BDRV_SECTOR_SIZE)) {
129 error_setg(errp, "Specified size is not multiple of %llu",
130 BDRV_SECTOR_SIZE);
131 return -EINVAL;
134 s->offset = offset;
135 s->has_size = has_size;
136 s->size = has_size ? size : real_size - offset;
138 return 0;
141 static int raw_reopen_prepare(BDRVReopenState *reopen_state,
142 BlockReopenQueue *queue, Error **errp)
144 bool has_size;
145 uint64_t offset, size;
146 int ret;
148 GLOBAL_STATE_CODE();
149 GRAPH_RDLOCK_GUARD_MAINLOOP();
151 assert(reopen_state != NULL);
152 assert(reopen_state->bs != NULL);
154 reopen_state->opaque = g_new0(BDRVRawState, 1);
156 ret = raw_read_options(reopen_state->options, &offset, &has_size, &size,
157 errp);
158 if (ret < 0) {
159 return ret;
162 ret = raw_apply_options(reopen_state->bs, reopen_state->opaque,
163 offset, has_size, size, errp);
164 if (ret < 0) {
165 return ret;
168 return 0;
171 static void raw_reopen_commit(BDRVReopenState *state)
173 BDRVRawState *new_s = state->opaque;
174 BDRVRawState *s = state->bs->opaque;
176 memcpy(s, new_s, sizeof(BDRVRawState));
178 g_free(state->opaque);
179 state->opaque = NULL;
182 static void raw_reopen_abort(BDRVReopenState *state)
184 g_free(state->opaque);
185 state->opaque = NULL;
188 /* Check and adjust the offset, against 'offset' and 'size' options. */
189 static inline int raw_adjust_offset(BlockDriverState *bs, int64_t *offset,
190 int64_t bytes, bool is_write)
192 BDRVRawState *s = bs->opaque;
194 if (s->has_size && (*offset > s->size || bytes > (s->size - *offset))) {
195 /* There's not enough space for the write, or the read request is
196 * out-of-range. Don't read/write anything to prevent leaking out of
197 * the size specified in options. */
198 return is_write ? -ENOSPC : -EINVAL;
201 if (*offset > INT64_MAX - s->offset) {
202 return -EINVAL;
204 *offset += s->offset;
206 return 0;
209 static int coroutine_fn GRAPH_RDLOCK
210 raw_co_preadv(BlockDriverState *bs, int64_t offset, int64_t bytes,
211 QEMUIOVector *qiov, BdrvRequestFlags flags)
213 int ret;
215 ret = raw_adjust_offset(bs, &offset, bytes, false);
216 if (ret) {
217 return ret;
220 BLKDBG_CO_EVENT(bs->file, BLKDBG_READ_AIO);
221 return bdrv_co_preadv(bs->file, offset, bytes, qiov, flags);
224 static int coroutine_fn GRAPH_RDLOCK
225 raw_co_pwritev(BlockDriverState *bs, int64_t offset, int64_t bytes,
226 QEMUIOVector *qiov, BdrvRequestFlags flags)
228 void *buf = NULL;
229 BlockDriver *drv;
230 QEMUIOVector local_qiov;
231 int ret;
233 if (bs->probed && offset < BLOCK_PROBE_BUF_SIZE && bytes) {
234 /* Handling partial writes would be a pain - so we just
235 * require that guests have 512-byte request alignment if
236 * probing occurred */
237 QEMU_BUILD_BUG_ON(BLOCK_PROBE_BUF_SIZE != 512);
238 QEMU_BUILD_BUG_ON(BDRV_SECTOR_SIZE != 512);
239 assert(offset == 0 && bytes >= BLOCK_PROBE_BUF_SIZE);
241 buf = qemu_try_blockalign(bs->file->bs, 512);
242 if (!buf) {
243 ret = -ENOMEM;
244 goto fail;
247 ret = qemu_iovec_to_buf(qiov, 0, buf, 512);
248 if (ret != 512) {
249 ret = -EINVAL;
250 goto fail;
253 drv = bdrv_probe_all(buf, 512, NULL);
254 if (drv != bs->drv) {
255 ret = -EPERM;
256 goto fail;
259 /* Use the checked buffer, a malicious guest might be overwriting its
260 * original buffer in the background. */
261 qemu_iovec_init(&local_qiov, qiov->niov + 1);
262 qemu_iovec_add(&local_qiov, buf, 512);
263 qemu_iovec_concat(&local_qiov, qiov, 512, qiov->size - 512);
264 qiov = &local_qiov;
266 flags &= ~BDRV_REQ_REGISTERED_BUF;
269 ret = raw_adjust_offset(bs, &offset, bytes, true);
270 if (ret) {
271 goto fail;
274 BLKDBG_CO_EVENT(bs->file, BLKDBG_WRITE_AIO);
275 ret = bdrv_co_pwritev(bs->file, offset, bytes, qiov, flags);
277 fail:
278 if (qiov == &local_qiov) {
279 qemu_iovec_destroy(&local_qiov);
281 qemu_vfree(buf);
282 return ret;
285 static int coroutine_fn GRAPH_RDLOCK
286 raw_co_block_status(BlockDriverState *bs, bool want_zero, int64_t offset,
287 int64_t bytes, int64_t *pnum, int64_t *map,
288 BlockDriverState **file)
290 BDRVRawState *s = bs->opaque;
291 *pnum = bytes;
292 *file = bs->file->bs;
293 *map = offset + s->offset;
294 return BDRV_BLOCK_RAW | BDRV_BLOCK_OFFSET_VALID;
297 static int coroutine_fn GRAPH_RDLOCK
298 raw_co_pwrite_zeroes(BlockDriverState *bs, int64_t offset, int64_t bytes,
299 BdrvRequestFlags flags)
301 int ret;
303 ret = raw_adjust_offset(bs, &offset, bytes, true);
304 if (ret) {
305 return ret;
307 return bdrv_co_pwrite_zeroes(bs->file, offset, bytes, flags);
310 static int coroutine_fn GRAPH_RDLOCK
311 raw_co_pdiscard(BlockDriverState *bs, int64_t offset, int64_t bytes)
313 int ret;
315 ret = raw_adjust_offset(bs, &offset, bytes, true);
316 if (ret) {
317 return ret;
319 return bdrv_co_pdiscard(bs->file, offset, bytes);
322 static int coroutine_fn GRAPH_RDLOCK
323 raw_co_zone_report(BlockDriverState *bs, int64_t offset,
324 unsigned int *nr_zones,
325 BlockZoneDescriptor *zones)
327 return bdrv_co_zone_report(bs->file->bs, offset, nr_zones, zones);
330 static int coroutine_fn GRAPH_RDLOCK
331 raw_co_zone_mgmt(BlockDriverState *bs, BlockZoneOp op,
332 int64_t offset, int64_t len)
334 return bdrv_co_zone_mgmt(bs->file->bs, op, offset, len);
337 static int coroutine_fn GRAPH_RDLOCK
338 raw_co_zone_append(BlockDriverState *bs,int64_t *offset, QEMUIOVector *qiov,
339 BdrvRequestFlags flags)
341 return bdrv_co_zone_append(bs->file->bs, offset, qiov, flags);
344 static int64_t coroutine_fn GRAPH_RDLOCK
345 raw_co_getlength(BlockDriverState *bs)
347 int64_t len;
348 BDRVRawState *s = bs->opaque;
350 /* Update size. It should not change unless the file was externally
351 * modified. */
352 len = bdrv_co_getlength(bs->file->bs);
353 if (len < 0) {
354 return len;
357 if (len < s->offset) {
358 s->size = 0;
359 } else {
360 if (s->has_size) {
361 /* Try to honour the size */
362 s->size = MIN(s->size, len - s->offset);
363 } else {
364 s->size = len - s->offset;
368 return s->size;
371 static BlockMeasureInfo *raw_measure(QemuOpts *opts, BlockDriverState *in_bs,
372 Error **errp)
374 BlockMeasureInfo *info;
375 int64_t required;
377 if (in_bs) {
378 required = bdrv_getlength(in_bs);
379 if (required < 0) {
380 error_setg_errno(errp, -required, "Unable to get image size");
381 return NULL;
383 } else {
384 required = ROUND_UP(qemu_opt_get_size_del(opts, BLOCK_OPT_SIZE, 0),
385 BDRV_SECTOR_SIZE);
388 info = g_new0(BlockMeasureInfo, 1);
389 info->required = required;
391 /* Unallocated sectors count towards the file size in raw images */
392 info->fully_allocated = info->required;
393 return info;
396 static int coroutine_fn GRAPH_RDLOCK
397 raw_co_get_info(BlockDriverState *bs, BlockDriverInfo *bdi)
399 return bdrv_co_get_info(bs->file->bs, bdi);
402 static void GRAPH_RDLOCK raw_refresh_limits(BlockDriverState *bs, Error **errp)
404 bs->bl.has_variable_length = bs->file->bs->bl.has_variable_length;
406 if (bs->probed) {
407 /* To make it easier to protect the first sector, any probed
408 * image is restricted to read-modify-write on sub-sector
409 * operations. */
410 bs->bl.request_alignment = BDRV_SECTOR_SIZE;
414 static int coroutine_fn GRAPH_RDLOCK
415 raw_co_truncate(BlockDriverState *bs, int64_t offset, bool exact,
416 PreallocMode prealloc, BdrvRequestFlags flags, Error **errp)
418 BDRVRawState *s = bs->opaque;
420 if (s->has_size) {
421 error_setg(errp, "Cannot resize fixed-size raw disks");
422 return -ENOTSUP;
425 if (INT64_MAX - offset < s->offset) {
426 error_setg(errp, "Disk size too large for the chosen offset");
427 return -EINVAL;
430 s->size = offset;
431 offset += s->offset;
432 return bdrv_co_truncate(bs->file, offset, exact, prealloc, flags, errp);
435 static void coroutine_fn GRAPH_RDLOCK
436 raw_co_eject(BlockDriverState *bs, bool eject_flag)
438 bdrv_co_eject(bs->file->bs, eject_flag);
441 static void coroutine_fn GRAPH_RDLOCK
442 raw_co_lock_medium(BlockDriverState *bs, bool locked)
444 bdrv_co_lock_medium(bs->file->bs, locked);
447 static int coroutine_fn GRAPH_RDLOCK
448 raw_co_ioctl(BlockDriverState *bs, unsigned long int req, void *buf)
450 BDRVRawState *s = bs->opaque;
451 if (s->offset || s->has_size) {
452 return -ENOTSUP;
454 return bdrv_co_ioctl(bs->file->bs, req, buf);
457 static int GRAPH_RDLOCK raw_has_zero_init(BlockDriverState *bs)
459 return bdrv_has_zero_init(bs->file->bs);
462 static int coroutine_fn GRAPH_UNLOCKED
463 raw_co_create_opts(BlockDriver *drv, const char *filename,
464 QemuOpts *opts, Error **errp)
466 return bdrv_co_create_file(filename, opts, errp);
469 static int raw_open(BlockDriverState *bs, QDict *options, int flags,
470 Error **errp)
472 BDRVRawState *s = bs->opaque;
473 bool has_size;
474 uint64_t offset, size;
475 BdrvChildRole file_role;
476 int ret;
478 GLOBAL_STATE_CODE();
480 ret = raw_read_options(options, &offset, &has_size, &size, errp);
481 if (ret < 0) {
482 return ret;
486 * Without offset and a size limit, this driver behaves very much
487 * like a filter. With any such limit, it does not.
489 if (offset || has_size) {
490 file_role = BDRV_CHILD_DATA | BDRV_CHILD_PRIMARY;
491 } else {
492 file_role = BDRV_CHILD_FILTERED | BDRV_CHILD_PRIMARY;
495 bdrv_open_child(NULL, options, "file", bs, &child_of_bds,
496 file_role, false, errp);
498 GRAPH_RDLOCK_GUARD_MAINLOOP();
499 if (!bs->file) {
500 return -EINVAL;
503 bs->sg = bdrv_is_sg(bs->file->bs);
504 bs->supported_write_flags = BDRV_REQ_WRITE_UNCHANGED |
505 (BDRV_REQ_FUA & bs->file->bs->supported_write_flags);
506 bs->supported_zero_flags = BDRV_REQ_WRITE_UNCHANGED |
507 ((BDRV_REQ_FUA | BDRV_REQ_MAY_UNMAP | BDRV_REQ_NO_FALLBACK) &
508 bs->file->bs->supported_zero_flags);
509 bs->supported_truncate_flags = bs->file->bs->supported_truncate_flags &
510 BDRV_REQ_ZERO_WRITE;
512 if (bs->probed && !bdrv_is_read_only(bs)) {
513 bdrv_refresh_filename(bs->file->bs);
514 fprintf(stderr,
515 "WARNING: Image format was not specified for '%s' and probing "
516 "guessed raw.\n"
517 " Automatically detecting the format is dangerous for "
518 "raw images, write operations on block 0 will be restricted.\n"
519 " Specify the 'raw' format explicitly to remove the "
520 "restrictions.\n",
521 bs->file->bs->filename);
524 ret = raw_apply_options(bs, s, offset, has_size, size, errp);
525 if (ret < 0) {
526 return ret;
529 if (bdrv_is_sg(bs) && (s->offset || s->has_size)) {
530 error_setg(errp, "Cannot use offset/size with SCSI generic devices");
531 return -EINVAL;
534 return 0;
537 static int raw_probe(const uint8_t *buf, int buf_size, const char *filename)
539 /* smallest possible positive score so that raw is used if and only if no
540 * other block driver works
542 return 1;
545 static int GRAPH_RDLOCK
546 raw_probe_blocksizes(BlockDriverState *bs, BlockSizes *bsz)
548 BDRVRawState *s = bs->opaque;
549 int ret;
551 ret = bdrv_probe_blocksizes(bs->file->bs, bsz);
552 if (ret < 0) {
553 return ret;
556 if (!QEMU_IS_ALIGNED(s->offset, MAX(bsz->log, bsz->phys))) {
557 return -ENOTSUP;
560 return 0;
563 static int GRAPH_RDLOCK
564 raw_probe_geometry(BlockDriverState *bs, HDGeometry *geo)
566 BDRVRawState *s = bs->opaque;
567 if (s->offset || s->has_size) {
568 return -ENOTSUP;
570 return bdrv_probe_geometry(bs->file->bs, geo);
573 static int coroutine_fn GRAPH_RDLOCK
574 raw_co_copy_range_from(BlockDriverState *bs,
575 BdrvChild *src, int64_t src_offset,
576 BdrvChild *dst, int64_t dst_offset,
577 int64_t bytes, BdrvRequestFlags read_flags,
578 BdrvRequestFlags write_flags)
580 int ret;
582 ret = raw_adjust_offset(bs, &src_offset, bytes, false);
583 if (ret) {
584 return ret;
586 return bdrv_co_copy_range_from(bs->file, src_offset, dst, dst_offset,
587 bytes, read_flags, write_flags);
590 static int coroutine_fn GRAPH_RDLOCK
591 raw_co_copy_range_to(BlockDriverState *bs,
592 BdrvChild *src, int64_t src_offset,
593 BdrvChild *dst, int64_t dst_offset,
594 int64_t bytes, BdrvRequestFlags read_flags,
595 BdrvRequestFlags write_flags)
597 int ret;
599 ret = raw_adjust_offset(bs, &dst_offset, bytes, true);
600 if (ret) {
601 return ret;
603 return bdrv_co_copy_range_to(src, src_offset, bs->file, dst_offset, bytes,
604 read_flags, write_flags);
607 static const char *const raw_strong_runtime_opts[] = {
608 "offset",
609 "size",
611 NULL
614 static void GRAPH_RDLOCK raw_cancel_in_flight(BlockDriverState *bs)
616 bdrv_cancel_in_flight(bs->file->bs);
619 static void raw_child_perm(BlockDriverState *bs, BdrvChild *c,
620 BdrvChildRole role,
621 BlockReopenQueue *reopen_queue,
622 uint64_t parent_perm, uint64_t parent_shared,
623 uint64_t *nperm, uint64_t *nshared)
625 bdrv_default_perms(bs, c, role, reopen_queue, parent_perm,
626 parent_shared, nperm, nshared);
629 * bdrv_default_perms() may add WRITE and/or RESIZE (see comment in
630 * bdrv_default_perms_for_storage() for an explanation) but we only need
631 * them if they are in parent_perm. Drop WRITE and RESIZE whenever possible
632 * to avoid permission conflicts.
634 *nperm &= ~(BLK_PERM_WRITE | BLK_PERM_RESIZE);
635 *nperm |= parent_perm & (BLK_PERM_WRITE | BLK_PERM_RESIZE);
638 BlockDriver bdrv_raw = {
639 .format_name = "raw",
640 .instance_size = sizeof(BDRVRawState),
641 .supports_zoned_children = true,
642 .bdrv_probe = &raw_probe,
643 .bdrv_reopen_prepare = &raw_reopen_prepare,
644 .bdrv_reopen_commit = &raw_reopen_commit,
645 .bdrv_reopen_abort = &raw_reopen_abort,
646 .bdrv_open = &raw_open,
647 .bdrv_child_perm = raw_child_perm,
648 .bdrv_co_create_opts = &raw_co_create_opts,
649 .bdrv_co_preadv = &raw_co_preadv,
650 .bdrv_co_pwritev = &raw_co_pwritev,
651 .bdrv_co_pwrite_zeroes = &raw_co_pwrite_zeroes,
652 .bdrv_co_pdiscard = &raw_co_pdiscard,
653 .bdrv_co_zone_report = &raw_co_zone_report,
654 .bdrv_co_zone_mgmt = &raw_co_zone_mgmt,
655 .bdrv_co_zone_append = &raw_co_zone_append,
656 .bdrv_co_block_status = &raw_co_block_status,
657 .bdrv_co_copy_range_from = &raw_co_copy_range_from,
658 .bdrv_co_copy_range_to = &raw_co_copy_range_to,
659 .bdrv_co_truncate = &raw_co_truncate,
660 .bdrv_co_getlength = &raw_co_getlength,
661 .is_format = true,
662 .bdrv_measure = &raw_measure,
663 .bdrv_co_get_info = &raw_co_get_info,
664 .bdrv_refresh_limits = &raw_refresh_limits,
665 .bdrv_probe_blocksizes = &raw_probe_blocksizes,
666 .bdrv_probe_geometry = &raw_probe_geometry,
667 .bdrv_co_eject = &raw_co_eject,
668 .bdrv_co_lock_medium = &raw_co_lock_medium,
669 .bdrv_co_ioctl = &raw_co_ioctl,
670 .create_opts = &raw_create_opts,
671 .bdrv_has_zero_init = &raw_has_zero_init,
672 .strong_runtime_opts = raw_strong_runtime_opts,
673 .mutable_opts = mutable_opts,
674 .bdrv_cancel_in_flight = raw_cancel_in_flight,
677 static void bdrv_raw_init(void)
679 bdrv_register(&bdrv_raw);
682 block_init(bdrv_raw_init);