monitor: allow device to be ejected if no disk is inserted
[qemu.git] / block.c
blob3fc296921130faef71e4edcf105ddb168c400b6b
1 /*
2 * QEMU System Emulator block driver
4 * Copyright (c) 2003 Fabrice Bellard
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:
13 * The above copyright notice and this permission notice shall be included in
14 * all copies or substantial portions of the Software.
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.
24 #include "config-host.h"
25 #include "qemu-common.h"
26 #include "monitor.h"
27 #include "block_int.h"
28 #include "module.h"
29 #include "qemu-objects.h"
31 #ifdef CONFIG_BSD
32 #include <sys/types.h>
33 #include <sys/stat.h>
34 #include <sys/ioctl.h>
35 #include <sys/queue.h>
36 #ifndef __DragonFly__
37 #include <sys/disk.h>
38 #endif
39 #endif
41 #ifdef _WIN32
42 #include <windows.h>
43 #endif
45 static BlockDriverAIOCB *bdrv_aio_readv_em(BlockDriverState *bs,
46 int64_t sector_num, QEMUIOVector *qiov, int nb_sectors,
47 BlockDriverCompletionFunc *cb, void *opaque);
48 static BlockDriverAIOCB *bdrv_aio_writev_em(BlockDriverState *bs,
49 int64_t sector_num, QEMUIOVector *qiov, int nb_sectors,
50 BlockDriverCompletionFunc *cb, void *opaque);
51 static BlockDriverAIOCB *bdrv_aio_flush_em(BlockDriverState *bs,
52 BlockDriverCompletionFunc *cb, void *opaque);
53 static BlockDriverAIOCB *bdrv_aio_noop_em(BlockDriverState *bs,
54 BlockDriverCompletionFunc *cb, void *opaque);
55 static int bdrv_read_em(BlockDriverState *bs, int64_t sector_num,
56 uint8_t *buf, int nb_sectors);
57 static int bdrv_write_em(BlockDriverState *bs, int64_t sector_num,
58 const uint8_t *buf, int nb_sectors);
60 static QTAILQ_HEAD(, BlockDriverState) bdrv_states =
61 QTAILQ_HEAD_INITIALIZER(bdrv_states);
63 static QLIST_HEAD(, BlockDriver) bdrv_drivers =
64 QLIST_HEAD_INITIALIZER(bdrv_drivers);
66 /* If non-zero, use only whitelisted block drivers */
67 static int use_bdrv_whitelist;
69 int path_is_absolute(const char *path)
71 const char *p;
72 #ifdef _WIN32
73 /* specific case for names like: "\\.\d:" */
74 if (*path == '/' || *path == '\\')
75 return 1;
76 #endif
77 p = strchr(path, ':');
78 if (p)
79 p++;
80 else
81 p = path;
82 #ifdef _WIN32
83 return (*p == '/' || *p == '\\');
84 #else
85 return (*p == '/');
86 #endif
89 /* if filename is absolute, just copy it to dest. Otherwise, build a
90 path to it by considering it is relative to base_path. URL are
91 supported. */
92 void path_combine(char *dest, int dest_size,
93 const char *base_path,
94 const char *filename)
96 const char *p, *p1;
97 int len;
99 if (dest_size <= 0)
100 return;
101 if (path_is_absolute(filename)) {
102 pstrcpy(dest, dest_size, filename);
103 } else {
104 p = strchr(base_path, ':');
105 if (p)
106 p++;
107 else
108 p = base_path;
109 p1 = strrchr(base_path, '/');
110 #ifdef _WIN32
112 const char *p2;
113 p2 = strrchr(base_path, '\\');
114 if (!p1 || p2 > p1)
115 p1 = p2;
117 #endif
118 if (p1)
119 p1++;
120 else
121 p1 = base_path;
122 if (p1 > p)
123 p = p1;
124 len = p - base_path;
125 if (len > dest_size - 1)
126 len = dest_size - 1;
127 memcpy(dest, base_path, len);
128 dest[len] = '\0';
129 pstrcat(dest, dest_size, filename);
133 void bdrv_register(BlockDriver *bdrv)
135 if (!bdrv->bdrv_aio_readv) {
136 /* add AIO emulation layer */
137 bdrv->bdrv_aio_readv = bdrv_aio_readv_em;
138 bdrv->bdrv_aio_writev = bdrv_aio_writev_em;
139 } else if (!bdrv->bdrv_read) {
140 /* add synchronous IO emulation layer */
141 bdrv->bdrv_read = bdrv_read_em;
142 bdrv->bdrv_write = bdrv_write_em;
145 if (!bdrv->bdrv_aio_flush)
146 bdrv->bdrv_aio_flush = bdrv_aio_flush_em;
148 QLIST_INSERT_HEAD(&bdrv_drivers, bdrv, list);
151 /* create a new block device (by default it is empty) */
152 BlockDriverState *bdrv_new(const char *device_name)
154 BlockDriverState *bs;
156 bs = qemu_mallocz(sizeof(BlockDriverState));
157 pstrcpy(bs->device_name, sizeof(bs->device_name), device_name);
158 if (device_name[0] != '\0') {
159 QTAILQ_INSERT_TAIL(&bdrv_states, bs, list);
161 return bs;
164 BlockDriver *bdrv_find_format(const char *format_name)
166 BlockDriver *drv1;
167 QLIST_FOREACH(drv1, &bdrv_drivers, list) {
168 if (!strcmp(drv1->format_name, format_name)) {
169 return drv1;
172 return NULL;
175 static int bdrv_is_whitelisted(BlockDriver *drv)
177 static const char *whitelist[] = {
178 CONFIG_BDRV_WHITELIST
180 const char **p;
182 if (!whitelist[0])
183 return 1; /* no whitelist, anything goes */
185 for (p = whitelist; *p; p++) {
186 if (!strcmp(drv->format_name, *p)) {
187 return 1;
190 return 0;
193 BlockDriver *bdrv_find_whitelisted_format(const char *format_name)
195 BlockDriver *drv = bdrv_find_format(format_name);
196 return drv && bdrv_is_whitelisted(drv) ? drv : NULL;
199 int bdrv_create(BlockDriver *drv, const char* filename,
200 QEMUOptionParameter *options)
202 if (!drv->bdrv_create)
203 return -ENOTSUP;
205 return drv->bdrv_create(filename, options);
208 int bdrv_create_file(const char* filename, QEMUOptionParameter *options)
210 BlockDriver *drv;
212 drv = bdrv_find_protocol(filename);
213 if (drv == NULL) {
214 drv = bdrv_find_format("file");
217 return bdrv_create(drv, filename, options);
220 #ifdef _WIN32
221 void get_tmp_filename(char *filename, int size)
223 char temp_dir[MAX_PATH];
225 GetTempPath(MAX_PATH, temp_dir);
226 GetTempFileName(temp_dir, "qem", 0, filename);
228 #else
229 void get_tmp_filename(char *filename, int size)
231 int fd;
232 const char *tmpdir;
233 /* XXX: race condition possible */
234 tmpdir = getenv("TMPDIR");
235 if (!tmpdir)
236 tmpdir = "/tmp";
237 snprintf(filename, size, "%s/vl.XXXXXX", tmpdir);
238 fd = mkstemp(filename);
239 close(fd);
241 #endif
243 #ifdef _WIN32
244 static int is_windows_drive_prefix(const char *filename)
246 return (((filename[0] >= 'a' && filename[0] <= 'z') ||
247 (filename[0] >= 'A' && filename[0] <= 'Z')) &&
248 filename[1] == ':');
251 int is_windows_drive(const char *filename)
253 if (is_windows_drive_prefix(filename) &&
254 filename[2] == '\0')
255 return 1;
256 if (strstart(filename, "\\\\.\\", NULL) ||
257 strstart(filename, "//./", NULL))
258 return 1;
259 return 0;
261 #endif
264 * Detect host devices. By convention, /dev/cdrom[N] is always
265 * recognized as a host CDROM.
267 static BlockDriver *find_hdev_driver(const char *filename)
269 int score_max = 0, score;
270 BlockDriver *drv = NULL, *d;
272 QLIST_FOREACH(d, &bdrv_drivers, list) {
273 if (d->bdrv_probe_device) {
274 score = d->bdrv_probe_device(filename);
275 if (score > score_max) {
276 score_max = score;
277 drv = d;
282 return drv;
285 BlockDriver *bdrv_find_protocol(const char *filename)
287 BlockDriver *drv1;
288 char protocol[128];
289 int len;
290 const char *p;
291 int is_drive;
293 /* TODO Drivers without bdrv_file_open must be specified explicitly */
295 #ifdef _WIN32
296 is_drive = is_windows_drive(filename) ||
297 is_windows_drive_prefix(filename);
298 #else
299 is_drive = 0;
300 #endif
301 p = strchr(filename, ':');
302 if (!p || is_drive) {
303 drv1 = find_hdev_driver(filename);
304 if (!drv1) {
305 drv1 = bdrv_find_format("file");
307 return drv1;
309 len = p - filename;
310 if (len > sizeof(protocol) - 1)
311 len = sizeof(protocol) - 1;
312 memcpy(protocol, filename, len);
313 protocol[len] = '\0';
314 QLIST_FOREACH(drv1, &bdrv_drivers, list) {
315 if (drv1->protocol_name &&
316 !strcmp(drv1->protocol_name, protocol)) {
317 return drv1;
320 return NULL;
323 static BlockDriver *find_image_format(const char *filename)
325 int ret, score, score_max;
326 BlockDriver *drv1, *drv;
327 uint8_t buf[2048];
328 BlockDriverState *bs;
330 ret = bdrv_file_open(&bs, filename, 0);
331 if (ret < 0)
332 return NULL;
334 /* Return the raw BlockDriver * to scsi-generic devices or empty drives */
335 if (bs->sg || !bdrv_is_inserted(bs)) {
336 bdrv_delete(bs);
337 return bdrv_find_format("raw");
340 ret = bdrv_pread(bs, 0, buf, sizeof(buf));
341 bdrv_delete(bs);
342 if (ret < 0) {
343 return NULL;
346 score_max = 0;
347 drv = NULL;
348 QLIST_FOREACH(drv1, &bdrv_drivers, list) {
349 if (drv1->bdrv_probe) {
350 score = drv1->bdrv_probe(buf, ret, filename);
351 if (score > score_max) {
352 score_max = score;
353 drv = drv1;
357 return drv;
361 * Set the current 'total_sectors' value
363 static int refresh_total_sectors(BlockDriverState *bs, int64_t hint)
365 BlockDriver *drv = bs->drv;
367 /* Do not attempt drv->bdrv_getlength() on scsi-generic devices */
368 if (bs->sg)
369 return 0;
371 /* query actual device if possible, otherwise just trust the hint */
372 if (drv->bdrv_getlength) {
373 int64_t length = drv->bdrv_getlength(bs);
374 if (length < 0) {
375 return length;
377 hint = length >> BDRV_SECTOR_BITS;
380 bs->total_sectors = hint;
381 return 0;
385 * Common part for opening disk images and files
387 static int bdrv_open_common(BlockDriverState *bs, const char *filename,
388 int flags, BlockDriver *drv)
390 int ret, open_flags;
392 assert(drv != NULL);
394 bs->file = NULL;
395 bs->total_sectors = 0;
396 bs->is_temporary = 0;
397 bs->encrypted = 0;
398 bs->valid_key = 0;
399 bs->open_flags = flags;
400 /* buffer_alignment defaulted to 512, drivers can change this value */
401 bs->buffer_alignment = 512;
403 pstrcpy(bs->filename, sizeof(bs->filename), filename);
405 if (use_bdrv_whitelist && !bdrv_is_whitelisted(drv)) {
406 return -ENOTSUP;
409 bs->drv = drv;
410 bs->opaque = qemu_mallocz(drv->instance_size);
413 * Yes, BDRV_O_NOCACHE aka O_DIRECT means we have to present a
414 * write cache to the guest. We do need the fdatasync to flush
415 * out transactions for block allocations, and we maybe have a
416 * volatile write cache in our backing device to deal with.
418 if (flags & (BDRV_O_CACHE_WB|BDRV_O_NOCACHE))
419 bs->enable_write_cache = 1;
422 * Clear flags that are internal to the block layer before opening the
423 * image.
425 open_flags = flags & ~(BDRV_O_SNAPSHOT | BDRV_O_NO_BACKING);
428 * Snapshots should be writeable.
430 if (bs->is_temporary) {
431 open_flags |= BDRV_O_RDWR;
434 /* Open the image, either directly or using a protocol */
435 if (drv->bdrv_file_open) {
436 ret = drv->bdrv_file_open(bs, filename, open_flags);
437 } else {
438 ret = bdrv_file_open(&bs->file, filename, open_flags);
439 if (ret >= 0) {
440 ret = drv->bdrv_open(bs, open_flags);
444 if (ret < 0) {
445 goto free_and_fail;
448 bs->keep_read_only = bs->read_only = !(open_flags & BDRV_O_RDWR);
450 ret = refresh_total_sectors(bs, bs->total_sectors);
451 if (ret < 0) {
452 goto free_and_fail;
455 #ifndef _WIN32
456 if (bs->is_temporary) {
457 unlink(filename);
459 #endif
460 return 0;
462 free_and_fail:
463 if (bs->file) {
464 bdrv_delete(bs->file);
465 bs->file = NULL;
467 qemu_free(bs->opaque);
468 bs->opaque = NULL;
469 bs->drv = NULL;
470 return ret;
474 * Opens a file using a protocol (file, host_device, nbd, ...)
476 int bdrv_file_open(BlockDriverState **pbs, const char *filename, int flags)
478 BlockDriverState *bs;
479 BlockDriver *drv;
480 int ret;
482 drv = bdrv_find_protocol(filename);
483 if (!drv) {
484 return -ENOENT;
487 bs = bdrv_new("");
488 ret = bdrv_open_common(bs, filename, flags, drv);
489 if (ret < 0) {
490 bdrv_delete(bs);
491 return ret;
493 bs->growable = 1;
494 *pbs = bs;
495 return 0;
499 * Opens a disk image (raw, qcow2, vmdk, ...)
501 int bdrv_open(BlockDriverState *bs, const char *filename, int flags,
502 BlockDriver *drv)
504 int ret;
506 if (flags & BDRV_O_SNAPSHOT) {
507 BlockDriverState *bs1;
508 int64_t total_size;
509 int is_protocol = 0;
510 BlockDriver *bdrv_qcow2;
511 QEMUOptionParameter *options;
512 char tmp_filename[PATH_MAX];
513 char backing_filename[PATH_MAX];
515 /* if snapshot, we create a temporary backing file and open it
516 instead of opening 'filename' directly */
518 /* if there is a backing file, use it */
519 bs1 = bdrv_new("");
520 ret = bdrv_open(bs1, filename, 0, drv);
521 if (ret < 0) {
522 bdrv_delete(bs1);
523 return ret;
525 total_size = bdrv_getlength(bs1) & BDRV_SECTOR_MASK;
527 if (bs1->drv && bs1->drv->protocol_name)
528 is_protocol = 1;
530 bdrv_delete(bs1);
532 get_tmp_filename(tmp_filename, sizeof(tmp_filename));
534 /* Real path is meaningless for protocols */
535 if (is_protocol)
536 snprintf(backing_filename, sizeof(backing_filename),
537 "%s", filename);
538 else if (!realpath(filename, backing_filename))
539 return -errno;
541 bdrv_qcow2 = bdrv_find_format("qcow2");
542 options = parse_option_parameters("", bdrv_qcow2->create_options, NULL);
544 set_option_parameter_int(options, BLOCK_OPT_SIZE, total_size);
545 set_option_parameter(options, BLOCK_OPT_BACKING_FILE, backing_filename);
546 if (drv) {
547 set_option_parameter(options, BLOCK_OPT_BACKING_FMT,
548 drv->format_name);
551 ret = bdrv_create(bdrv_qcow2, tmp_filename, options);
552 free_option_parameters(options);
553 if (ret < 0) {
554 return ret;
557 filename = tmp_filename;
558 drv = bdrv_qcow2;
559 bs->is_temporary = 1;
562 /* Find the right image format driver */
563 if (!drv) {
564 drv = find_image_format(filename);
567 if (!drv) {
568 ret = -ENOENT;
569 goto unlink_and_fail;
572 /* Open the image */
573 ret = bdrv_open_common(bs, filename, flags, drv);
574 if (ret < 0) {
575 goto unlink_and_fail;
578 /* If there is a backing file, use it */
579 if ((flags & BDRV_O_NO_BACKING) == 0 && bs->backing_file[0] != '\0') {
580 char backing_filename[PATH_MAX];
581 int back_flags;
582 BlockDriver *back_drv = NULL;
584 bs->backing_hd = bdrv_new("");
585 path_combine(backing_filename, sizeof(backing_filename),
586 filename, bs->backing_file);
587 if (bs->backing_format[0] != '\0')
588 back_drv = bdrv_find_format(bs->backing_format);
590 /* backing files always opened read-only */
591 back_flags =
592 flags & ~(BDRV_O_RDWR | BDRV_O_SNAPSHOT | BDRV_O_NO_BACKING);
594 ret = bdrv_open(bs->backing_hd, backing_filename, back_flags, back_drv);
595 if (ret < 0) {
596 bdrv_close(bs);
597 return ret;
599 if (bs->is_temporary) {
600 bs->backing_hd->keep_read_only = !(flags & BDRV_O_RDWR);
601 } else {
602 /* base image inherits from "parent" */
603 bs->backing_hd->keep_read_only = bs->keep_read_only;
607 if (!bdrv_key_required(bs)) {
608 /* call the change callback */
609 bs->media_changed = 1;
610 if (bs->change_cb)
611 bs->change_cb(bs->change_opaque);
614 return 0;
616 unlink_and_fail:
617 if (bs->is_temporary) {
618 unlink(filename);
620 return ret;
623 void bdrv_close(BlockDriverState *bs)
625 if (bs->drv) {
626 if (bs->backing_hd) {
627 bdrv_delete(bs->backing_hd);
628 bs->backing_hd = NULL;
630 bs->drv->bdrv_close(bs);
631 qemu_free(bs->opaque);
632 #ifdef _WIN32
633 if (bs->is_temporary) {
634 unlink(bs->filename);
636 #endif
637 bs->opaque = NULL;
638 bs->drv = NULL;
640 if (bs->file != NULL) {
641 bdrv_close(bs->file);
644 /* call the change callback */
645 bs->media_changed = 1;
646 if (bs->change_cb)
647 bs->change_cb(bs->change_opaque);
651 void bdrv_close_all(void)
653 BlockDriverState *bs;
655 QTAILQ_FOREACH(bs, &bdrv_states, list) {
656 bdrv_close(bs);
660 void bdrv_delete(BlockDriverState *bs)
662 /* remove from list, if necessary */
663 if (bs->device_name[0] != '\0') {
664 QTAILQ_REMOVE(&bdrv_states, bs, list);
667 bdrv_close(bs);
668 if (bs->file != NULL) {
669 bdrv_delete(bs->file);
672 qemu_free(bs);
676 * Run consistency checks on an image
678 * Returns the number of errors or -errno when an internal error occurs
680 int bdrv_check(BlockDriverState *bs)
682 if (bs->drv->bdrv_check == NULL) {
683 return -ENOTSUP;
686 return bs->drv->bdrv_check(bs);
689 /* commit COW file into the raw image */
690 int bdrv_commit(BlockDriverState *bs)
692 BlockDriver *drv = bs->drv;
693 int64_t i, total_sectors;
694 int n, j, ro, open_flags;
695 int ret = 0, rw_ret = 0;
696 unsigned char sector[BDRV_SECTOR_SIZE];
697 char filename[1024];
698 BlockDriverState *bs_rw, *bs_ro;
700 if (!drv)
701 return -ENOMEDIUM;
703 if (!bs->backing_hd) {
704 return -ENOTSUP;
707 if (bs->backing_hd->keep_read_only) {
708 return -EACCES;
711 ro = bs->backing_hd->read_only;
712 strncpy(filename, bs->backing_hd->filename, sizeof(filename));
713 open_flags = bs->backing_hd->open_flags;
715 if (ro) {
716 /* re-open as RW */
717 bdrv_delete(bs->backing_hd);
718 bs->backing_hd = NULL;
719 bs_rw = bdrv_new("");
720 rw_ret = bdrv_open(bs_rw, filename, open_flags | BDRV_O_RDWR, drv);
721 if (rw_ret < 0) {
722 bdrv_delete(bs_rw);
723 /* try to re-open read-only */
724 bs_ro = bdrv_new("");
725 ret = bdrv_open(bs_ro, filename, open_flags & ~BDRV_O_RDWR, drv);
726 if (ret < 0) {
727 bdrv_delete(bs_ro);
728 /* drive not functional anymore */
729 bs->drv = NULL;
730 return ret;
732 bs->backing_hd = bs_ro;
733 return rw_ret;
735 bs->backing_hd = bs_rw;
738 total_sectors = bdrv_getlength(bs) >> BDRV_SECTOR_BITS;
739 for (i = 0; i < total_sectors;) {
740 if (drv->bdrv_is_allocated(bs, i, 65536, &n)) {
741 for(j = 0; j < n; j++) {
742 if (bdrv_read(bs, i, sector, 1) != 0) {
743 ret = -EIO;
744 goto ro_cleanup;
747 if (bdrv_write(bs->backing_hd, i, sector, 1) != 0) {
748 ret = -EIO;
749 goto ro_cleanup;
751 i++;
753 } else {
754 i += n;
758 if (drv->bdrv_make_empty) {
759 ret = drv->bdrv_make_empty(bs);
760 bdrv_flush(bs);
764 * Make sure all data we wrote to the backing device is actually
765 * stable on disk.
767 if (bs->backing_hd)
768 bdrv_flush(bs->backing_hd);
770 ro_cleanup:
772 if (ro) {
773 /* re-open as RO */
774 bdrv_delete(bs->backing_hd);
775 bs->backing_hd = NULL;
776 bs_ro = bdrv_new("");
777 ret = bdrv_open(bs_ro, filename, open_flags & ~BDRV_O_RDWR, drv);
778 if (ret < 0) {
779 bdrv_delete(bs_ro);
780 /* drive not functional anymore */
781 bs->drv = NULL;
782 return ret;
784 bs->backing_hd = bs_ro;
785 bs->backing_hd->keep_read_only = 0;
788 return ret;
791 void bdrv_commit_all(void)
793 BlockDriverState *bs;
795 QTAILQ_FOREACH(bs, &bdrv_states, list) {
796 bdrv_commit(bs);
801 * Return values:
802 * 0 - success
803 * -EINVAL - backing format specified, but no file
804 * -ENOSPC - can't update the backing file because no space is left in the
805 * image file header
806 * -ENOTSUP - format driver doesn't support changing the backing file
808 int bdrv_change_backing_file(BlockDriverState *bs,
809 const char *backing_file, const char *backing_fmt)
811 BlockDriver *drv = bs->drv;
813 if (drv->bdrv_change_backing_file != NULL) {
814 return drv->bdrv_change_backing_file(bs, backing_file, backing_fmt);
815 } else {
816 return -ENOTSUP;
820 static int bdrv_check_byte_request(BlockDriverState *bs, int64_t offset,
821 size_t size)
823 int64_t len;
825 if (!bdrv_is_inserted(bs))
826 return -ENOMEDIUM;
828 if (bs->growable)
829 return 0;
831 len = bdrv_getlength(bs);
833 if (offset < 0)
834 return -EIO;
836 if ((offset > len) || (len - offset < size))
837 return -EIO;
839 return 0;
842 static int bdrv_check_request(BlockDriverState *bs, int64_t sector_num,
843 int nb_sectors)
845 return bdrv_check_byte_request(bs, sector_num * BDRV_SECTOR_SIZE,
846 nb_sectors * BDRV_SECTOR_SIZE);
849 /* return < 0 if error. See bdrv_write() for the return codes */
850 int bdrv_read(BlockDriverState *bs, int64_t sector_num,
851 uint8_t *buf, int nb_sectors)
853 BlockDriver *drv = bs->drv;
855 if (!drv)
856 return -ENOMEDIUM;
857 if (bdrv_check_request(bs, sector_num, nb_sectors))
858 return -EIO;
860 return drv->bdrv_read(bs, sector_num, buf, nb_sectors);
863 static void set_dirty_bitmap(BlockDriverState *bs, int64_t sector_num,
864 int nb_sectors, int dirty)
866 int64_t start, end;
867 unsigned long val, idx, bit;
869 start = sector_num / BDRV_SECTORS_PER_DIRTY_CHUNK;
870 end = (sector_num + nb_sectors - 1) / BDRV_SECTORS_PER_DIRTY_CHUNK;
872 for (; start <= end; start++) {
873 idx = start / (sizeof(unsigned long) * 8);
874 bit = start % (sizeof(unsigned long) * 8);
875 val = bs->dirty_bitmap[idx];
876 if (dirty) {
877 if (!(val & (1 << bit))) {
878 bs->dirty_count++;
879 val |= 1 << bit;
881 } else {
882 if (val & (1 << bit)) {
883 bs->dirty_count--;
884 val &= ~(1 << bit);
887 bs->dirty_bitmap[idx] = val;
891 /* Return < 0 if error. Important errors are:
892 -EIO generic I/O error (may happen for all errors)
893 -ENOMEDIUM No media inserted.
894 -EINVAL Invalid sector number or nb_sectors
895 -EACCES Trying to write a read-only device
897 int bdrv_write(BlockDriverState *bs, int64_t sector_num,
898 const uint8_t *buf, int nb_sectors)
900 BlockDriver *drv = bs->drv;
901 if (!bs->drv)
902 return -ENOMEDIUM;
903 if (bs->read_only)
904 return -EACCES;
905 if (bdrv_check_request(bs, sector_num, nb_sectors))
906 return -EIO;
908 if (bs->dirty_bitmap) {
909 set_dirty_bitmap(bs, sector_num, nb_sectors, 1);
912 if (bs->wr_highest_sector < sector_num + nb_sectors - 1) {
913 bs->wr_highest_sector = sector_num + nb_sectors - 1;
916 return drv->bdrv_write(bs, sector_num, buf, nb_sectors);
919 int bdrv_pread(BlockDriverState *bs, int64_t offset,
920 void *buf, int count1)
922 uint8_t tmp_buf[BDRV_SECTOR_SIZE];
923 int len, nb_sectors, count;
924 int64_t sector_num;
925 int ret;
927 count = count1;
928 /* first read to align to sector start */
929 len = (BDRV_SECTOR_SIZE - offset) & (BDRV_SECTOR_SIZE - 1);
930 if (len > count)
931 len = count;
932 sector_num = offset >> BDRV_SECTOR_BITS;
933 if (len > 0) {
934 if ((ret = bdrv_read(bs, sector_num, tmp_buf, 1)) < 0)
935 return ret;
936 memcpy(buf, tmp_buf + (offset & (BDRV_SECTOR_SIZE - 1)), len);
937 count -= len;
938 if (count == 0)
939 return count1;
940 sector_num++;
941 buf += len;
944 /* read the sectors "in place" */
945 nb_sectors = count >> BDRV_SECTOR_BITS;
946 if (nb_sectors > 0) {
947 if ((ret = bdrv_read(bs, sector_num, buf, nb_sectors)) < 0)
948 return ret;
949 sector_num += nb_sectors;
950 len = nb_sectors << BDRV_SECTOR_BITS;
951 buf += len;
952 count -= len;
955 /* add data from the last sector */
956 if (count > 0) {
957 if ((ret = bdrv_read(bs, sector_num, tmp_buf, 1)) < 0)
958 return ret;
959 memcpy(buf, tmp_buf, count);
961 return count1;
964 int bdrv_pwrite(BlockDriverState *bs, int64_t offset,
965 const void *buf, int count1)
967 uint8_t tmp_buf[BDRV_SECTOR_SIZE];
968 int len, nb_sectors, count;
969 int64_t sector_num;
970 int ret;
972 count = count1;
973 /* first write to align to sector start */
974 len = (BDRV_SECTOR_SIZE - offset) & (BDRV_SECTOR_SIZE - 1);
975 if (len > count)
976 len = count;
977 sector_num = offset >> BDRV_SECTOR_BITS;
978 if (len > 0) {
979 if ((ret = bdrv_read(bs, sector_num, tmp_buf, 1)) < 0)
980 return ret;
981 memcpy(tmp_buf + (offset & (BDRV_SECTOR_SIZE - 1)), buf, len);
982 if ((ret = bdrv_write(bs, sector_num, tmp_buf, 1)) < 0)
983 return ret;
984 count -= len;
985 if (count == 0)
986 return count1;
987 sector_num++;
988 buf += len;
991 /* write the sectors "in place" */
992 nb_sectors = count >> BDRV_SECTOR_BITS;
993 if (nb_sectors > 0) {
994 if ((ret = bdrv_write(bs, sector_num, buf, nb_sectors)) < 0)
995 return ret;
996 sector_num += nb_sectors;
997 len = nb_sectors << BDRV_SECTOR_BITS;
998 buf += len;
999 count -= len;
1002 /* add data from the last sector */
1003 if (count > 0) {
1004 if ((ret = bdrv_read(bs, sector_num, tmp_buf, 1)) < 0)
1005 return ret;
1006 memcpy(tmp_buf, buf, count);
1007 if ((ret = bdrv_write(bs, sector_num, tmp_buf, 1)) < 0)
1008 return ret;
1010 return count1;
1014 * Truncate file to 'offset' bytes (needed only for file protocols)
1016 int bdrv_truncate(BlockDriverState *bs, int64_t offset)
1018 BlockDriver *drv = bs->drv;
1019 int ret;
1020 if (!drv)
1021 return -ENOMEDIUM;
1022 if (!drv->bdrv_truncate)
1023 return -ENOTSUP;
1024 if (bs->read_only)
1025 return -EACCES;
1026 ret = drv->bdrv_truncate(bs, offset);
1027 if (ret == 0) {
1028 ret = refresh_total_sectors(bs, offset >> BDRV_SECTOR_BITS);
1030 return ret;
1034 * Length of a file in bytes. Return < 0 if error or unknown.
1036 int64_t bdrv_getlength(BlockDriverState *bs)
1038 BlockDriver *drv = bs->drv;
1039 if (!drv)
1040 return -ENOMEDIUM;
1042 /* Fixed size devices use the total_sectors value for speed instead of
1043 issuing a length query (like lseek) on each call. Also, legacy block
1044 drivers don't provide a bdrv_getlength function and must use
1045 total_sectors. */
1046 if (!bs->growable || !drv->bdrv_getlength) {
1047 return bs->total_sectors * BDRV_SECTOR_SIZE;
1049 return drv->bdrv_getlength(bs);
1052 /* return 0 as number of sectors if no device present or error */
1053 void bdrv_get_geometry(BlockDriverState *bs, uint64_t *nb_sectors_ptr)
1055 int64_t length;
1056 length = bdrv_getlength(bs);
1057 if (length < 0)
1058 length = 0;
1059 else
1060 length = length >> BDRV_SECTOR_BITS;
1061 *nb_sectors_ptr = length;
1064 struct partition {
1065 uint8_t boot_ind; /* 0x80 - active */
1066 uint8_t head; /* starting head */
1067 uint8_t sector; /* starting sector */
1068 uint8_t cyl; /* starting cylinder */
1069 uint8_t sys_ind; /* What partition type */
1070 uint8_t end_head; /* end head */
1071 uint8_t end_sector; /* end sector */
1072 uint8_t end_cyl; /* end cylinder */
1073 uint32_t start_sect; /* starting sector counting from 0 */
1074 uint32_t nr_sects; /* nr of sectors in partition */
1075 } __attribute__((packed));
1077 /* try to guess the disk logical geometry from the MSDOS partition table. Return 0 if OK, -1 if could not guess */
1078 static int guess_disk_lchs(BlockDriverState *bs,
1079 int *pcylinders, int *pheads, int *psectors)
1081 uint8_t buf[BDRV_SECTOR_SIZE];
1082 int ret, i, heads, sectors, cylinders;
1083 struct partition *p;
1084 uint32_t nr_sects;
1085 uint64_t nb_sectors;
1087 bdrv_get_geometry(bs, &nb_sectors);
1089 ret = bdrv_read(bs, 0, buf, 1);
1090 if (ret < 0)
1091 return -1;
1092 /* test msdos magic */
1093 if (buf[510] != 0x55 || buf[511] != 0xaa)
1094 return -1;
1095 for(i = 0; i < 4; i++) {
1096 p = ((struct partition *)(buf + 0x1be)) + i;
1097 nr_sects = le32_to_cpu(p->nr_sects);
1098 if (nr_sects && p->end_head) {
1099 /* We make the assumption that the partition terminates on
1100 a cylinder boundary */
1101 heads = p->end_head + 1;
1102 sectors = p->end_sector & 63;
1103 if (sectors == 0)
1104 continue;
1105 cylinders = nb_sectors / (heads * sectors);
1106 if (cylinders < 1 || cylinders > 16383)
1107 continue;
1108 *pheads = heads;
1109 *psectors = sectors;
1110 *pcylinders = cylinders;
1111 #if 0
1112 printf("guessed geometry: LCHS=%d %d %d\n",
1113 cylinders, heads, sectors);
1114 #endif
1115 return 0;
1118 return -1;
1121 void bdrv_guess_geometry(BlockDriverState *bs, int *pcyls, int *pheads, int *psecs)
1123 int translation, lba_detected = 0;
1124 int cylinders, heads, secs;
1125 uint64_t nb_sectors;
1127 /* if a geometry hint is available, use it */
1128 bdrv_get_geometry(bs, &nb_sectors);
1129 bdrv_get_geometry_hint(bs, &cylinders, &heads, &secs);
1130 translation = bdrv_get_translation_hint(bs);
1131 if (cylinders != 0) {
1132 *pcyls = cylinders;
1133 *pheads = heads;
1134 *psecs = secs;
1135 } else {
1136 if (guess_disk_lchs(bs, &cylinders, &heads, &secs) == 0) {
1137 if (heads > 16) {
1138 /* if heads > 16, it means that a BIOS LBA
1139 translation was active, so the default
1140 hardware geometry is OK */
1141 lba_detected = 1;
1142 goto default_geometry;
1143 } else {
1144 *pcyls = cylinders;
1145 *pheads = heads;
1146 *psecs = secs;
1147 /* disable any translation to be in sync with
1148 the logical geometry */
1149 if (translation == BIOS_ATA_TRANSLATION_AUTO) {
1150 bdrv_set_translation_hint(bs,
1151 BIOS_ATA_TRANSLATION_NONE);
1154 } else {
1155 default_geometry:
1156 /* if no geometry, use a standard physical disk geometry */
1157 cylinders = nb_sectors / (16 * 63);
1159 if (cylinders > 16383)
1160 cylinders = 16383;
1161 else if (cylinders < 2)
1162 cylinders = 2;
1163 *pcyls = cylinders;
1164 *pheads = 16;
1165 *psecs = 63;
1166 if ((lba_detected == 1) && (translation == BIOS_ATA_TRANSLATION_AUTO)) {
1167 if ((*pcyls * *pheads) <= 131072) {
1168 bdrv_set_translation_hint(bs,
1169 BIOS_ATA_TRANSLATION_LARGE);
1170 } else {
1171 bdrv_set_translation_hint(bs,
1172 BIOS_ATA_TRANSLATION_LBA);
1176 bdrv_set_geometry_hint(bs, *pcyls, *pheads, *psecs);
1180 void bdrv_set_geometry_hint(BlockDriverState *bs,
1181 int cyls, int heads, int secs)
1183 bs->cyls = cyls;
1184 bs->heads = heads;
1185 bs->secs = secs;
1188 void bdrv_set_type_hint(BlockDriverState *bs, int type)
1190 bs->type = type;
1191 bs->removable = ((type == BDRV_TYPE_CDROM ||
1192 type == BDRV_TYPE_FLOPPY));
1195 void bdrv_set_translation_hint(BlockDriverState *bs, int translation)
1197 bs->translation = translation;
1200 void bdrv_get_geometry_hint(BlockDriverState *bs,
1201 int *pcyls, int *pheads, int *psecs)
1203 *pcyls = bs->cyls;
1204 *pheads = bs->heads;
1205 *psecs = bs->secs;
1208 int bdrv_get_type_hint(BlockDriverState *bs)
1210 return bs->type;
1213 int bdrv_get_translation_hint(BlockDriverState *bs)
1215 return bs->translation;
1218 void bdrv_set_on_error(BlockDriverState *bs, BlockErrorAction on_read_error,
1219 BlockErrorAction on_write_error)
1221 bs->on_read_error = on_read_error;
1222 bs->on_write_error = on_write_error;
1225 BlockErrorAction bdrv_get_on_error(BlockDriverState *bs, int is_read)
1227 return is_read ? bs->on_read_error : bs->on_write_error;
1230 int bdrv_is_removable(BlockDriverState *bs)
1232 return bs->removable;
1235 int bdrv_is_read_only(BlockDriverState *bs)
1237 return bs->read_only;
1240 int bdrv_is_sg(BlockDriverState *bs)
1242 return bs->sg;
1245 int bdrv_enable_write_cache(BlockDriverState *bs)
1247 return bs->enable_write_cache;
1250 /* XXX: no longer used */
1251 void bdrv_set_change_cb(BlockDriverState *bs,
1252 void (*change_cb)(void *opaque), void *opaque)
1254 bs->change_cb = change_cb;
1255 bs->change_opaque = opaque;
1258 int bdrv_is_encrypted(BlockDriverState *bs)
1260 if (bs->backing_hd && bs->backing_hd->encrypted)
1261 return 1;
1262 return bs->encrypted;
1265 int bdrv_key_required(BlockDriverState *bs)
1267 BlockDriverState *backing_hd = bs->backing_hd;
1269 if (backing_hd && backing_hd->encrypted && !backing_hd->valid_key)
1270 return 1;
1271 return (bs->encrypted && !bs->valid_key);
1274 int bdrv_set_key(BlockDriverState *bs, const char *key)
1276 int ret;
1277 if (bs->backing_hd && bs->backing_hd->encrypted) {
1278 ret = bdrv_set_key(bs->backing_hd, key);
1279 if (ret < 0)
1280 return ret;
1281 if (!bs->encrypted)
1282 return 0;
1284 if (!bs->encrypted) {
1285 return -EINVAL;
1286 } else if (!bs->drv || !bs->drv->bdrv_set_key) {
1287 return -ENOMEDIUM;
1289 ret = bs->drv->bdrv_set_key(bs, key);
1290 if (ret < 0) {
1291 bs->valid_key = 0;
1292 } else if (!bs->valid_key) {
1293 bs->valid_key = 1;
1294 /* call the change callback now, we skipped it on open */
1295 bs->media_changed = 1;
1296 if (bs->change_cb)
1297 bs->change_cb(bs->change_opaque);
1299 return ret;
1302 void bdrv_get_format(BlockDriverState *bs, char *buf, int buf_size)
1304 if (!bs->drv) {
1305 buf[0] = '\0';
1306 } else {
1307 pstrcpy(buf, buf_size, bs->drv->format_name);
1311 void bdrv_iterate_format(void (*it)(void *opaque, const char *name),
1312 void *opaque)
1314 BlockDriver *drv;
1316 QLIST_FOREACH(drv, &bdrv_drivers, list) {
1317 it(opaque, drv->format_name);
1321 BlockDriverState *bdrv_find(const char *name)
1323 BlockDriverState *bs;
1325 QTAILQ_FOREACH(bs, &bdrv_states, list) {
1326 if (!strcmp(name, bs->device_name)) {
1327 return bs;
1330 return NULL;
1333 BlockDriverState *bdrv_next(BlockDriverState *bs)
1335 if (!bs) {
1336 return QTAILQ_FIRST(&bdrv_states);
1338 return QTAILQ_NEXT(bs, list);
1341 void bdrv_iterate(void (*it)(void *opaque, BlockDriverState *bs), void *opaque)
1343 BlockDriverState *bs;
1345 QTAILQ_FOREACH(bs, &bdrv_states, list) {
1346 it(opaque, bs);
1350 const char *bdrv_get_device_name(BlockDriverState *bs)
1352 return bs->device_name;
1355 void bdrv_flush(BlockDriverState *bs)
1357 if (bs->open_flags & BDRV_O_NO_FLUSH) {
1358 return;
1361 if (bs->drv && bs->drv->bdrv_flush)
1362 bs->drv->bdrv_flush(bs);
1365 void bdrv_flush_all(void)
1367 BlockDriverState *bs;
1369 QTAILQ_FOREACH(bs, &bdrv_states, list) {
1370 if (bs->drv && !bdrv_is_read_only(bs) &&
1371 (!bdrv_is_removable(bs) || bdrv_is_inserted(bs))) {
1372 bdrv_flush(bs);
1377 int bdrv_has_zero_init(BlockDriverState *bs)
1379 assert(bs->drv);
1381 if (bs->drv->no_zero_init) {
1382 return 0;
1383 } else if (bs->file) {
1384 return bdrv_has_zero_init(bs->file);
1387 return 1;
1391 * Returns true iff the specified sector is present in the disk image. Drivers
1392 * not implementing the functionality are assumed to not support backing files,
1393 * hence all their sectors are reported as allocated.
1395 * 'pnum' is set to the number of sectors (including and immediately following
1396 * the specified sector) that are known to be in the same
1397 * allocated/unallocated state.
1399 * 'nb_sectors' is the max value 'pnum' should be set to.
1401 int bdrv_is_allocated(BlockDriverState *bs, int64_t sector_num, int nb_sectors,
1402 int *pnum)
1404 int64_t n;
1405 if (!bs->drv->bdrv_is_allocated) {
1406 if (sector_num >= bs->total_sectors) {
1407 *pnum = 0;
1408 return 0;
1410 n = bs->total_sectors - sector_num;
1411 *pnum = (n < nb_sectors) ? (n) : (nb_sectors);
1412 return 1;
1414 return bs->drv->bdrv_is_allocated(bs, sector_num, nb_sectors, pnum);
1417 void bdrv_mon_event(const BlockDriverState *bdrv,
1418 BlockMonEventAction action, int is_read)
1420 QObject *data;
1421 const char *action_str;
1423 switch (action) {
1424 case BDRV_ACTION_REPORT:
1425 action_str = "report";
1426 break;
1427 case BDRV_ACTION_IGNORE:
1428 action_str = "ignore";
1429 break;
1430 case BDRV_ACTION_STOP:
1431 action_str = "stop";
1432 break;
1433 default:
1434 abort();
1437 data = qobject_from_jsonf("{ 'device': %s, 'action': %s, 'operation': %s }",
1438 bdrv->device_name,
1439 action_str,
1440 is_read ? "read" : "write");
1441 monitor_protocol_event(QEVENT_BLOCK_IO_ERROR, data);
1443 qobject_decref(data);
1446 static void bdrv_print_dict(QObject *obj, void *opaque)
1448 QDict *bs_dict;
1449 Monitor *mon = opaque;
1451 bs_dict = qobject_to_qdict(obj);
1453 monitor_printf(mon, "%s: type=%s removable=%d",
1454 qdict_get_str(bs_dict, "device"),
1455 qdict_get_str(bs_dict, "type"),
1456 qdict_get_bool(bs_dict, "removable"));
1458 if (qdict_get_bool(bs_dict, "removable")) {
1459 monitor_printf(mon, " locked=%d", qdict_get_bool(bs_dict, "locked"));
1462 if (qdict_haskey(bs_dict, "inserted")) {
1463 QDict *qdict = qobject_to_qdict(qdict_get(bs_dict, "inserted"));
1465 monitor_printf(mon, " file=");
1466 monitor_print_filename(mon, qdict_get_str(qdict, "file"));
1467 if (qdict_haskey(qdict, "backing_file")) {
1468 monitor_printf(mon, " backing_file=");
1469 monitor_print_filename(mon, qdict_get_str(qdict, "backing_file"));
1471 monitor_printf(mon, " ro=%d drv=%s encrypted=%d",
1472 qdict_get_bool(qdict, "ro"),
1473 qdict_get_str(qdict, "drv"),
1474 qdict_get_bool(qdict, "encrypted"));
1475 } else {
1476 monitor_printf(mon, " [not inserted]");
1479 monitor_printf(mon, "\n");
1482 void bdrv_info_print(Monitor *mon, const QObject *data)
1484 qlist_iter(qobject_to_qlist(data), bdrv_print_dict, mon);
1487 void bdrv_info(Monitor *mon, QObject **ret_data)
1489 QList *bs_list;
1490 BlockDriverState *bs;
1492 bs_list = qlist_new();
1494 QTAILQ_FOREACH(bs, &bdrv_states, list) {
1495 QObject *bs_obj;
1496 const char *type = "unknown";
1498 switch(bs->type) {
1499 case BDRV_TYPE_HD:
1500 type = "hd";
1501 break;
1502 case BDRV_TYPE_CDROM:
1503 type = "cdrom";
1504 break;
1505 case BDRV_TYPE_FLOPPY:
1506 type = "floppy";
1507 break;
1510 bs_obj = qobject_from_jsonf("{ 'device': %s, 'type': %s, "
1511 "'removable': %i, 'locked': %i }",
1512 bs->device_name, type, bs->removable,
1513 bs->locked);
1515 if (bs->drv) {
1516 QObject *obj;
1517 QDict *bs_dict = qobject_to_qdict(bs_obj);
1519 obj = qobject_from_jsonf("{ 'file': %s, 'ro': %i, 'drv': %s, "
1520 "'encrypted': %i }",
1521 bs->filename, bs->read_only,
1522 bs->drv->format_name,
1523 bdrv_is_encrypted(bs));
1524 if (bs->backing_file[0] != '\0') {
1525 QDict *qdict = qobject_to_qdict(obj);
1526 qdict_put(qdict, "backing_file",
1527 qstring_from_str(bs->backing_file));
1530 qdict_put_obj(bs_dict, "inserted", obj);
1532 qlist_append_obj(bs_list, bs_obj);
1535 *ret_data = QOBJECT(bs_list);
1538 static void bdrv_stats_iter(QObject *data, void *opaque)
1540 QDict *qdict;
1541 Monitor *mon = opaque;
1543 qdict = qobject_to_qdict(data);
1544 monitor_printf(mon, "%s:", qdict_get_str(qdict, "device"));
1546 qdict = qobject_to_qdict(qdict_get(qdict, "stats"));
1547 monitor_printf(mon, " rd_bytes=%" PRId64
1548 " wr_bytes=%" PRId64
1549 " rd_operations=%" PRId64
1550 " wr_operations=%" PRId64
1551 "\n",
1552 qdict_get_int(qdict, "rd_bytes"),
1553 qdict_get_int(qdict, "wr_bytes"),
1554 qdict_get_int(qdict, "rd_operations"),
1555 qdict_get_int(qdict, "wr_operations"));
1558 void bdrv_stats_print(Monitor *mon, const QObject *data)
1560 qlist_iter(qobject_to_qlist(data), bdrv_stats_iter, mon);
1563 static QObject* bdrv_info_stats_bs(BlockDriverState *bs)
1565 QObject *res;
1566 QDict *dict;
1568 res = qobject_from_jsonf("{ 'stats': {"
1569 "'rd_bytes': %" PRId64 ","
1570 "'wr_bytes': %" PRId64 ","
1571 "'rd_operations': %" PRId64 ","
1572 "'wr_operations': %" PRId64 ","
1573 "'wr_highest_offset': %" PRId64
1574 "} }",
1575 bs->rd_bytes, bs->wr_bytes,
1576 bs->rd_ops, bs->wr_ops,
1577 bs->wr_highest_sector *
1578 (uint64_t)BDRV_SECTOR_SIZE);
1579 dict = qobject_to_qdict(res);
1581 if (*bs->device_name) {
1582 qdict_put(dict, "device", qstring_from_str(bs->device_name));
1585 if (bs->file) {
1586 QObject *parent = bdrv_info_stats_bs(bs->file);
1587 qdict_put_obj(dict, "parent", parent);
1590 return res;
1593 void bdrv_info_stats(Monitor *mon, QObject **ret_data)
1595 QObject *obj;
1596 QList *devices;
1597 BlockDriverState *bs;
1599 devices = qlist_new();
1601 QTAILQ_FOREACH(bs, &bdrv_states, list) {
1602 obj = bdrv_info_stats_bs(bs);
1603 qlist_append_obj(devices, obj);
1606 *ret_data = QOBJECT(devices);
1609 const char *bdrv_get_encrypted_filename(BlockDriverState *bs)
1611 if (bs->backing_hd && bs->backing_hd->encrypted)
1612 return bs->backing_file;
1613 else if (bs->encrypted)
1614 return bs->filename;
1615 else
1616 return NULL;
1619 void bdrv_get_backing_filename(BlockDriverState *bs,
1620 char *filename, int filename_size)
1622 if (!bs->backing_file) {
1623 pstrcpy(filename, filename_size, "");
1624 } else {
1625 pstrcpy(filename, filename_size, bs->backing_file);
1629 int bdrv_write_compressed(BlockDriverState *bs, int64_t sector_num,
1630 const uint8_t *buf, int nb_sectors)
1632 BlockDriver *drv = bs->drv;
1633 if (!drv)
1634 return -ENOMEDIUM;
1635 if (!drv->bdrv_write_compressed)
1636 return -ENOTSUP;
1637 if (bdrv_check_request(bs, sector_num, nb_sectors))
1638 return -EIO;
1640 if (bs->dirty_bitmap) {
1641 set_dirty_bitmap(bs, sector_num, nb_sectors, 1);
1644 return drv->bdrv_write_compressed(bs, sector_num, buf, nb_sectors);
1647 int bdrv_get_info(BlockDriverState *bs, BlockDriverInfo *bdi)
1649 BlockDriver *drv = bs->drv;
1650 if (!drv)
1651 return -ENOMEDIUM;
1652 if (!drv->bdrv_get_info)
1653 return -ENOTSUP;
1654 memset(bdi, 0, sizeof(*bdi));
1655 return drv->bdrv_get_info(bs, bdi);
1658 int bdrv_save_vmstate(BlockDriverState *bs, const uint8_t *buf,
1659 int64_t pos, int size)
1661 BlockDriver *drv = bs->drv;
1662 if (!drv)
1663 return -ENOMEDIUM;
1664 if (drv->bdrv_save_vmstate)
1665 return drv->bdrv_save_vmstate(bs, buf, pos, size);
1666 if (bs->file)
1667 return bdrv_save_vmstate(bs->file, buf, pos, size);
1668 return -ENOTSUP;
1671 int bdrv_load_vmstate(BlockDriverState *bs, uint8_t *buf,
1672 int64_t pos, int size)
1674 BlockDriver *drv = bs->drv;
1675 if (!drv)
1676 return -ENOMEDIUM;
1677 if (drv->bdrv_load_vmstate)
1678 return drv->bdrv_load_vmstate(bs, buf, pos, size);
1679 if (bs->file)
1680 return bdrv_load_vmstate(bs->file, buf, pos, size);
1681 return -ENOTSUP;
1684 void bdrv_debug_event(BlockDriverState *bs, BlkDebugEvent event)
1686 BlockDriver *drv = bs->drv;
1688 if (!drv || !drv->bdrv_debug_event) {
1689 return;
1692 return drv->bdrv_debug_event(bs, event);
1696 /**************************************************************/
1697 /* handling of snapshots */
1699 int bdrv_can_snapshot(BlockDriverState *bs)
1701 BlockDriver *drv = bs->drv;
1702 if (!drv || bdrv_is_removable(bs) || bdrv_is_read_only(bs)) {
1703 return 0;
1706 if (!drv->bdrv_snapshot_create) {
1707 if (bs->file != NULL) {
1708 return bdrv_can_snapshot(bs->file);
1710 return 0;
1713 return 1;
1716 int bdrv_snapshot_create(BlockDriverState *bs,
1717 QEMUSnapshotInfo *sn_info)
1719 BlockDriver *drv = bs->drv;
1720 if (!drv)
1721 return -ENOMEDIUM;
1722 if (drv->bdrv_snapshot_create)
1723 return drv->bdrv_snapshot_create(bs, sn_info);
1724 if (bs->file)
1725 return bdrv_snapshot_create(bs->file, sn_info);
1726 return -ENOTSUP;
1729 int bdrv_snapshot_goto(BlockDriverState *bs,
1730 const char *snapshot_id)
1732 BlockDriver *drv = bs->drv;
1733 int ret, open_ret;
1735 if (!drv)
1736 return -ENOMEDIUM;
1737 if (drv->bdrv_snapshot_goto)
1738 return drv->bdrv_snapshot_goto(bs, snapshot_id);
1740 if (bs->file) {
1741 drv->bdrv_close(bs);
1742 ret = bdrv_snapshot_goto(bs->file, snapshot_id);
1743 open_ret = drv->bdrv_open(bs, bs->open_flags);
1744 if (open_ret < 0) {
1745 bdrv_delete(bs->file);
1746 bs->drv = NULL;
1747 return open_ret;
1749 return ret;
1752 return -ENOTSUP;
1755 int bdrv_snapshot_delete(BlockDriverState *bs, const char *snapshot_id)
1757 BlockDriver *drv = bs->drv;
1758 if (!drv)
1759 return -ENOMEDIUM;
1760 if (drv->bdrv_snapshot_delete)
1761 return drv->bdrv_snapshot_delete(bs, snapshot_id);
1762 if (bs->file)
1763 return bdrv_snapshot_delete(bs->file, snapshot_id);
1764 return -ENOTSUP;
1767 int bdrv_snapshot_list(BlockDriverState *bs,
1768 QEMUSnapshotInfo **psn_info)
1770 BlockDriver *drv = bs->drv;
1771 if (!drv)
1772 return -ENOMEDIUM;
1773 if (drv->bdrv_snapshot_list)
1774 return drv->bdrv_snapshot_list(bs, psn_info);
1775 if (bs->file)
1776 return bdrv_snapshot_list(bs->file, psn_info);
1777 return -ENOTSUP;
1780 #define NB_SUFFIXES 4
1782 char *get_human_readable_size(char *buf, int buf_size, int64_t size)
1784 static const char suffixes[NB_SUFFIXES] = "KMGT";
1785 int64_t base;
1786 int i;
1788 if (size <= 999) {
1789 snprintf(buf, buf_size, "%" PRId64, size);
1790 } else {
1791 base = 1024;
1792 for(i = 0; i < NB_SUFFIXES; i++) {
1793 if (size < (10 * base)) {
1794 snprintf(buf, buf_size, "%0.1f%c",
1795 (double)size / base,
1796 suffixes[i]);
1797 break;
1798 } else if (size < (1000 * base) || i == (NB_SUFFIXES - 1)) {
1799 snprintf(buf, buf_size, "%" PRId64 "%c",
1800 ((size + (base >> 1)) / base),
1801 suffixes[i]);
1802 break;
1804 base = base * 1024;
1807 return buf;
1810 char *bdrv_snapshot_dump(char *buf, int buf_size, QEMUSnapshotInfo *sn)
1812 char buf1[128], date_buf[128], clock_buf[128];
1813 #ifdef _WIN32
1814 struct tm *ptm;
1815 #else
1816 struct tm tm;
1817 #endif
1818 time_t ti;
1819 int64_t secs;
1821 if (!sn) {
1822 snprintf(buf, buf_size,
1823 "%-10s%-20s%7s%20s%15s",
1824 "ID", "TAG", "VM SIZE", "DATE", "VM CLOCK");
1825 } else {
1826 ti = sn->date_sec;
1827 #ifdef _WIN32
1828 ptm = localtime(&ti);
1829 strftime(date_buf, sizeof(date_buf),
1830 "%Y-%m-%d %H:%M:%S", ptm);
1831 #else
1832 localtime_r(&ti, &tm);
1833 strftime(date_buf, sizeof(date_buf),
1834 "%Y-%m-%d %H:%M:%S", &tm);
1835 #endif
1836 secs = sn->vm_clock_nsec / 1000000000;
1837 snprintf(clock_buf, sizeof(clock_buf),
1838 "%02d:%02d:%02d.%03d",
1839 (int)(secs / 3600),
1840 (int)((secs / 60) % 60),
1841 (int)(secs % 60),
1842 (int)((sn->vm_clock_nsec / 1000000) % 1000));
1843 snprintf(buf, buf_size,
1844 "%-10s%-20s%7s%20s%15s",
1845 sn->id_str, sn->name,
1846 get_human_readable_size(buf1, sizeof(buf1), sn->vm_state_size),
1847 date_buf,
1848 clock_buf);
1850 return buf;
1854 /**************************************************************/
1855 /* async I/Os */
1857 BlockDriverAIOCB *bdrv_aio_readv(BlockDriverState *bs, int64_t sector_num,
1858 QEMUIOVector *qiov, int nb_sectors,
1859 BlockDriverCompletionFunc *cb, void *opaque)
1861 BlockDriver *drv = bs->drv;
1862 BlockDriverAIOCB *ret;
1864 if (!drv)
1865 return NULL;
1866 if (bdrv_check_request(bs, sector_num, nb_sectors))
1867 return NULL;
1869 ret = drv->bdrv_aio_readv(bs, sector_num, qiov, nb_sectors,
1870 cb, opaque);
1872 if (ret) {
1873 /* Update stats even though technically transfer has not happened. */
1874 bs->rd_bytes += (unsigned) nb_sectors * BDRV_SECTOR_SIZE;
1875 bs->rd_ops ++;
1878 return ret;
1881 BlockDriverAIOCB *bdrv_aio_writev(BlockDriverState *bs, int64_t sector_num,
1882 QEMUIOVector *qiov, int nb_sectors,
1883 BlockDriverCompletionFunc *cb, void *opaque)
1885 BlockDriver *drv = bs->drv;
1886 BlockDriverAIOCB *ret;
1888 if (!drv)
1889 return NULL;
1890 if (bs->read_only)
1891 return NULL;
1892 if (bdrv_check_request(bs, sector_num, nb_sectors))
1893 return NULL;
1895 if (bs->dirty_bitmap) {
1896 set_dirty_bitmap(bs, sector_num, nb_sectors, 1);
1899 ret = drv->bdrv_aio_writev(bs, sector_num, qiov, nb_sectors,
1900 cb, opaque);
1902 if (ret) {
1903 /* Update stats even though technically transfer has not happened. */
1904 bs->wr_bytes += (unsigned) nb_sectors * BDRV_SECTOR_SIZE;
1905 bs->wr_ops ++;
1906 if (bs->wr_highest_sector < sector_num + nb_sectors - 1) {
1907 bs->wr_highest_sector = sector_num + nb_sectors - 1;
1911 return ret;
1915 typedef struct MultiwriteCB {
1916 int error;
1917 int num_requests;
1918 int num_callbacks;
1919 struct {
1920 BlockDriverCompletionFunc *cb;
1921 void *opaque;
1922 QEMUIOVector *free_qiov;
1923 void *free_buf;
1924 } callbacks[];
1925 } MultiwriteCB;
1927 static void multiwrite_user_cb(MultiwriteCB *mcb)
1929 int i;
1931 for (i = 0; i < mcb->num_callbacks; i++) {
1932 mcb->callbacks[i].cb(mcb->callbacks[i].opaque, mcb->error);
1933 if (mcb->callbacks[i].free_qiov) {
1934 qemu_iovec_destroy(mcb->callbacks[i].free_qiov);
1936 qemu_free(mcb->callbacks[i].free_qiov);
1937 qemu_vfree(mcb->callbacks[i].free_buf);
1941 static void multiwrite_cb(void *opaque, int ret)
1943 MultiwriteCB *mcb = opaque;
1945 if (ret < 0 && !mcb->error) {
1946 mcb->error = ret;
1947 multiwrite_user_cb(mcb);
1950 mcb->num_requests--;
1951 if (mcb->num_requests == 0) {
1952 if (mcb->error == 0) {
1953 multiwrite_user_cb(mcb);
1955 qemu_free(mcb);
1959 static int multiwrite_req_compare(const void *a, const void *b)
1961 const BlockRequest *req1 = a, *req2 = b;
1964 * Note that we can't simply subtract req2->sector from req1->sector
1965 * here as that could overflow the return value.
1967 if (req1->sector > req2->sector) {
1968 return 1;
1969 } else if (req1->sector < req2->sector) {
1970 return -1;
1971 } else {
1972 return 0;
1977 * Takes a bunch of requests and tries to merge them. Returns the number of
1978 * requests that remain after merging.
1980 static int multiwrite_merge(BlockDriverState *bs, BlockRequest *reqs,
1981 int num_reqs, MultiwriteCB *mcb)
1983 int i, outidx;
1985 // Sort requests by start sector
1986 qsort(reqs, num_reqs, sizeof(*reqs), &multiwrite_req_compare);
1988 // Check if adjacent requests touch the same clusters. If so, combine them,
1989 // filling up gaps with zero sectors.
1990 outidx = 0;
1991 for (i = 1; i < num_reqs; i++) {
1992 int merge = 0;
1993 int64_t oldreq_last = reqs[outidx].sector + reqs[outidx].nb_sectors;
1995 // This handles the cases that are valid for all block drivers, namely
1996 // exactly sequential writes and overlapping writes.
1997 if (reqs[i].sector <= oldreq_last) {
1998 merge = 1;
2001 // The block driver may decide that it makes sense to combine requests
2002 // even if there is a gap of some sectors between them. In this case,
2003 // the gap is filled with zeros (therefore only applicable for yet
2004 // unused space in format like qcow2).
2005 if (!merge && bs->drv->bdrv_merge_requests) {
2006 merge = bs->drv->bdrv_merge_requests(bs, &reqs[outidx], &reqs[i]);
2009 if (reqs[outidx].qiov->niov + reqs[i].qiov->niov + 1 > IOV_MAX) {
2010 merge = 0;
2013 if (merge) {
2014 size_t size;
2015 QEMUIOVector *qiov = qemu_mallocz(sizeof(*qiov));
2016 qemu_iovec_init(qiov,
2017 reqs[outidx].qiov->niov + reqs[i].qiov->niov + 1);
2019 // Add the first request to the merged one. If the requests are
2020 // overlapping, drop the last sectors of the first request.
2021 size = (reqs[i].sector - reqs[outidx].sector) << 9;
2022 qemu_iovec_concat(qiov, reqs[outidx].qiov, size);
2024 // We might need to add some zeros between the two requests
2025 if (reqs[i].sector > oldreq_last) {
2026 size_t zero_bytes = (reqs[i].sector - oldreq_last) << 9;
2027 uint8_t *buf = qemu_blockalign(bs, zero_bytes);
2028 memset(buf, 0, zero_bytes);
2029 qemu_iovec_add(qiov, buf, zero_bytes);
2030 mcb->callbacks[i].free_buf = buf;
2033 // Add the second request
2034 qemu_iovec_concat(qiov, reqs[i].qiov, reqs[i].qiov->size);
2036 reqs[outidx].nb_sectors = qiov->size >> 9;
2037 reqs[outidx].qiov = qiov;
2039 mcb->callbacks[i].free_qiov = reqs[outidx].qiov;
2040 } else {
2041 outidx++;
2042 reqs[outidx].sector = reqs[i].sector;
2043 reqs[outidx].nb_sectors = reqs[i].nb_sectors;
2044 reqs[outidx].qiov = reqs[i].qiov;
2048 return outidx + 1;
2052 * Submit multiple AIO write requests at once.
2054 * On success, the function returns 0 and all requests in the reqs array have
2055 * been submitted. In error case this function returns -1, and any of the
2056 * requests may or may not be submitted yet. In particular, this means that the
2057 * callback will be called for some of the requests, for others it won't. The
2058 * caller must check the error field of the BlockRequest to wait for the right
2059 * callbacks (if error != 0, no callback will be called).
2061 * The implementation may modify the contents of the reqs array, e.g. to merge
2062 * requests. However, the fields opaque and error are left unmodified as they
2063 * are used to signal failure for a single request to the caller.
2065 int bdrv_aio_multiwrite(BlockDriverState *bs, BlockRequest *reqs, int num_reqs)
2067 BlockDriverAIOCB *acb;
2068 MultiwriteCB *mcb;
2069 int i;
2071 if (num_reqs == 0) {
2072 return 0;
2075 // Create MultiwriteCB structure
2076 mcb = qemu_mallocz(sizeof(*mcb) + num_reqs * sizeof(*mcb->callbacks));
2077 mcb->num_requests = 0;
2078 mcb->num_callbacks = num_reqs;
2080 for (i = 0; i < num_reqs; i++) {
2081 mcb->callbacks[i].cb = reqs[i].cb;
2082 mcb->callbacks[i].opaque = reqs[i].opaque;
2085 // Check for mergable requests
2086 num_reqs = multiwrite_merge(bs, reqs, num_reqs, mcb);
2088 // Run the aio requests
2089 for (i = 0; i < num_reqs; i++) {
2090 acb = bdrv_aio_writev(bs, reqs[i].sector, reqs[i].qiov,
2091 reqs[i].nb_sectors, multiwrite_cb, mcb);
2093 if (acb == NULL) {
2094 // We can only fail the whole thing if no request has been
2095 // submitted yet. Otherwise we'll wait for the submitted AIOs to
2096 // complete and report the error in the callback.
2097 if (mcb->num_requests == 0) {
2098 reqs[i].error = -EIO;
2099 goto fail;
2100 } else {
2101 mcb->num_requests++;
2102 multiwrite_cb(mcb, -EIO);
2103 break;
2105 } else {
2106 mcb->num_requests++;
2110 return 0;
2112 fail:
2113 qemu_free(mcb);
2114 return -1;
2117 BlockDriverAIOCB *bdrv_aio_flush(BlockDriverState *bs,
2118 BlockDriverCompletionFunc *cb, void *opaque)
2120 BlockDriver *drv = bs->drv;
2122 if (bs->open_flags & BDRV_O_NO_FLUSH) {
2123 return bdrv_aio_noop_em(bs, cb, opaque);
2126 if (!drv)
2127 return NULL;
2128 return drv->bdrv_aio_flush(bs, cb, opaque);
2131 void bdrv_aio_cancel(BlockDriverAIOCB *acb)
2133 acb->pool->cancel(acb);
2137 /**************************************************************/
2138 /* async block device emulation */
2140 typedef struct BlockDriverAIOCBSync {
2141 BlockDriverAIOCB common;
2142 QEMUBH *bh;
2143 int ret;
2144 /* vector translation state */
2145 QEMUIOVector *qiov;
2146 uint8_t *bounce;
2147 int is_write;
2148 } BlockDriverAIOCBSync;
2150 static void bdrv_aio_cancel_em(BlockDriverAIOCB *blockacb)
2152 BlockDriverAIOCBSync *acb =
2153 container_of(blockacb, BlockDriverAIOCBSync, common);
2154 qemu_bh_delete(acb->bh);
2155 acb->bh = NULL;
2156 qemu_aio_release(acb);
2159 static AIOPool bdrv_em_aio_pool = {
2160 .aiocb_size = sizeof(BlockDriverAIOCBSync),
2161 .cancel = bdrv_aio_cancel_em,
2164 static void bdrv_aio_bh_cb(void *opaque)
2166 BlockDriverAIOCBSync *acb = opaque;
2168 if (!acb->is_write)
2169 qemu_iovec_from_buffer(acb->qiov, acb->bounce, acb->qiov->size);
2170 qemu_vfree(acb->bounce);
2171 acb->common.cb(acb->common.opaque, acb->ret);
2172 qemu_bh_delete(acb->bh);
2173 acb->bh = NULL;
2174 qemu_aio_release(acb);
2177 static BlockDriverAIOCB *bdrv_aio_rw_vector(BlockDriverState *bs,
2178 int64_t sector_num,
2179 QEMUIOVector *qiov,
2180 int nb_sectors,
2181 BlockDriverCompletionFunc *cb,
2182 void *opaque,
2183 int is_write)
2186 BlockDriverAIOCBSync *acb;
2188 acb = qemu_aio_get(&bdrv_em_aio_pool, bs, cb, opaque);
2189 acb->is_write = is_write;
2190 acb->qiov = qiov;
2191 acb->bounce = qemu_blockalign(bs, qiov->size);
2193 if (!acb->bh)
2194 acb->bh = qemu_bh_new(bdrv_aio_bh_cb, acb);
2196 if (is_write) {
2197 qemu_iovec_to_buffer(acb->qiov, acb->bounce);
2198 acb->ret = bdrv_write(bs, sector_num, acb->bounce, nb_sectors);
2199 } else {
2200 acb->ret = bdrv_read(bs, sector_num, acb->bounce, nb_sectors);
2203 qemu_bh_schedule(acb->bh);
2205 return &acb->common;
2208 static BlockDriverAIOCB *bdrv_aio_readv_em(BlockDriverState *bs,
2209 int64_t sector_num, QEMUIOVector *qiov, int nb_sectors,
2210 BlockDriverCompletionFunc *cb, void *opaque)
2212 return bdrv_aio_rw_vector(bs, sector_num, qiov, nb_sectors, cb, opaque, 0);
2215 static BlockDriverAIOCB *bdrv_aio_writev_em(BlockDriverState *bs,
2216 int64_t sector_num, QEMUIOVector *qiov, int nb_sectors,
2217 BlockDriverCompletionFunc *cb, void *opaque)
2219 return bdrv_aio_rw_vector(bs, sector_num, qiov, nb_sectors, cb, opaque, 1);
2222 static BlockDriverAIOCB *bdrv_aio_flush_em(BlockDriverState *bs,
2223 BlockDriverCompletionFunc *cb, void *opaque)
2225 BlockDriverAIOCBSync *acb;
2227 acb = qemu_aio_get(&bdrv_em_aio_pool, bs, cb, opaque);
2228 acb->is_write = 1; /* don't bounce in the completion hadler */
2229 acb->qiov = NULL;
2230 acb->bounce = NULL;
2231 acb->ret = 0;
2233 if (!acb->bh)
2234 acb->bh = qemu_bh_new(bdrv_aio_bh_cb, acb);
2236 bdrv_flush(bs);
2237 qemu_bh_schedule(acb->bh);
2238 return &acb->common;
2241 static BlockDriverAIOCB *bdrv_aio_noop_em(BlockDriverState *bs,
2242 BlockDriverCompletionFunc *cb, void *opaque)
2244 BlockDriverAIOCBSync *acb;
2246 acb = qemu_aio_get(&bdrv_em_aio_pool, bs, cb, opaque);
2247 acb->is_write = 1; /* don't bounce in the completion handler */
2248 acb->qiov = NULL;
2249 acb->bounce = NULL;
2250 acb->ret = 0;
2252 if (!acb->bh) {
2253 acb->bh = qemu_bh_new(bdrv_aio_bh_cb, acb);
2256 qemu_bh_schedule(acb->bh);
2257 return &acb->common;
2260 /**************************************************************/
2261 /* sync block device emulation */
2263 static void bdrv_rw_em_cb(void *opaque, int ret)
2265 *(int *)opaque = ret;
2268 #define NOT_DONE 0x7fffffff
2270 static int bdrv_read_em(BlockDriverState *bs, int64_t sector_num,
2271 uint8_t *buf, int nb_sectors)
2273 int async_ret;
2274 BlockDriverAIOCB *acb;
2275 struct iovec iov;
2276 QEMUIOVector qiov;
2278 async_context_push();
2280 async_ret = NOT_DONE;
2281 iov.iov_base = (void *)buf;
2282 iov.iov_len = nb_sectors * BDRV_SECTOR_SIZE;
2283 qemu_iovec_init_external(&qiov, &iov, 1);
2284 acb = bdrv_aio_readv(bs, sector_num, &qiov, nb_sectors,
2285 bdrv_rw_em_cb, &async_ret);
2286 if (acb == NULL) {
2287 async_ret = -1;
2288 goto fail;
2291 while (async_ret == NOT_DONE) {
2292 qemu_aio_wait();
2296 fail:
2297 async_context_pop();
2298 return async_ret;
2301 static int bdrv_write_em(BlockDriverState *bs, int64_t sector_num,
2302 const uint8_t *buf, int nb_sectors)
2304 int async_ret;
2305 BlockDriverAIOCB *acb;
2306 struct iovec iov;
2307 QEMUIOVector qiov;
2309 async_context_push();
2311 async_ret = NOT_DONE;
2312 iov.iov_base = (void *)buf;
2313 iov.iov_len = nb_sectors * BDRV_SECTOR_SIZE;
2314 qemu_iovec_init_external(&qiov, &iov, 1);
2315 acb = bdrv_aio_writev(bs, sector_num, &qiov, nb_sectors,
2316 bdrv_rw_em_cb, &async_ret);
2317 if (acb == NULL) {
2318 async_ret = -1;
2319 goto fail;
2321 while (async_ret == NOT_DONE) {
2322 qemu_aio_wait();
2325 fail:
2326 async_context_pop();
2327 return async_ret;
2330 void bdrv_init(void)
2332 module_call_init(MODULE_INIT_BLOCK);
2335 void bdrv_init_with_whitelist(void)
2337 use_bdrv_whitelist = 1;
2338 bdrv_init();
2341 void *qemu_aio_get(AIOPool *pool, BlockDriverState *bs,
2342 BlockDriverCompletionFunc *cb, void *opaque)
2344 BlockDriverAIOCB *acb;
2346 if (pool->free_aiocb) {
2347 acb = pool->free_aiocb;
2348 pool->free_aiocb = acb->next;
2349 } else {
2350 acb = qemu_mallocz(pool->aiocb_size);
2351 acb->pool = pool;
2353 acb->bs = bs;
2354 acb->cb = cb;
2355 acb->opaque = opaque;
2356 return acb;
2359 void qemu_aio_release(void *p)
2361 BlockDriverAIOCB *acb = (BlockDriverAIOCB *)p;
2362 AIOPool *pool = acb->pool;
2363 acb->next = pool->free_aiocb;
2364 pool->free_aiocb = acb;
2367 /**************************************************************/
2368 /* removable device support */
2371 * Return TRUE if the media is present
2373 int bdrv_is_inserted(BlockDriverState *bs)
2375 BlockDriver *drv = bs->drv;
2376 int ret;
2377 if (!drv)
2378 return 0;
2379 if (!drv->bdrv_is_inserted)
2380 return 1;
2381 ret = drv->bdrv_is_inserted(bs);
2382 return ret;
2386 * Return TRUE if the media changed since the last call to this
2387 * function. It is currently only used for floppy disks
2389 int bdrv_media_changed(BlockDriverState *bs)
2391 BlockDriver *drv = bs->drv;
2392 int ret;
2394 if (!drv || !drv->bdrv_media_changed)
2395 ret = -ENOTSUP;
2396 else
2397 ret = drv->bdrv_media_changed(bs);
2398 if (ret == -ENOTSUP)
2399 ret = bs->media_changed;
2400 bs->media_changed = 0;
2401 return ret;
2405 * If eject_flag is TRUE, eject the media. Otherwise, close the tray
2407 int bdrv_eject(BlockDriverState *bs, int eject_flag)
2409 BlockDriver *drv = bs->drv;
2410 int ret;
2412 if (bs->locked) {
2413 return -EBUSY;
2416 if (!drv || !drv->bdrv_eject) {
2417 ret = -ENOTSUP;
2418 } else {
2419 ret = drv->bdrv_eject(bs, eject_flag);
2421 if (ret == -ENOTSUP) {
2422 if (eject_flag)
2423 bdrv_close(bs);
2424 ret = 0;
2427 return ret;
2430 int bdrv_is_locked(BlockDriverState *bs)
2432 return bs->locked;
2436 * Lock or unlock the media (if it is locked, the user won't be able
2437 * to eject it manually).
2439 void bdrv_set_locked(BlockDriverState *bs, int locked)
2441 BlockDriver *drv = bs->drv;
2443 bs->locked = locked;
2444 if (drv && drv->bdrv_set_locked) {
2445 drv->bdrv_set_locked(bs, locked);
2449 /* needed for generic scsi interface */
2451 int bdrv_ioctl(BlockDriverState *bs, unsigned long int req, void *buf)
2453 BlockDriver *drv = bs->drv;
2455 if (drv && drv->bdrv_ioctl)
2456 return drv->bdrv_ioctl(bs, req, buf);
2457 return -ENOTSUP;
2460 BlockDriverAIOCB *bdrv_aio_ioctl(BlockDriverState *bs,
2461 unsigned long int req, void *buf,
2462 BlockDriverCompletionFunc *cb, void *opaque)
2464 BlockDriver *drv = bs->drv;
2466 if (drv && drv->bdrv_aio_ioctl)
2467 return drv->bdrv_aio_ioctl(bs, req, buf, cb, opaque);
2468 return NULL;
2473 void *qemu_blockalign(BlockDriverState *bs, size_t size)
2475 return qemu_memalign((bs && bs->buffer_alignment) ? bs->buffer_alignment : 512, size);
2478 void bdrv_set_dirty_tracking(BlockDriverState *bs, int enable)
2480 int64_t bitmap_size;
2482 bs->dirty_count = 0;
2483 if (enable) {
2484 if (!bs->dirty_bitmap) {
2485 bitmap_size = (bdrv_getlength(bs) >> BDRV_SECTOR_BITS) +
2486 BDRV_SECTORS_PER_DIRTY_CHUNK * 8 - 1;
2487 bitmap_size /= BDRV_SECTORS_PER_DIRTY_CHUNK * 8;
2489 bs->dirty_bitmap = qemu_mallocz(bitmap_size);
2491 } else {
2492 if (bs->dirty_bitmap) {
2493 qemu_free(bs->dirty_bitmap);
2494 bs->dirty_bitmap = NULL;
2499 int bdrv_get_dirty(BlockDriverState *bs, int64_t sector)
2501 int64_t chunk = sector / (int64_t)BDRV_SECTORS_PER_DIRTY_CHUNK;
2503 if (bs->dirty_bitmap &&
2504 (sector << BDRV_SECTOR_BITS) < bdrv_getlength(bs)) {
2505 return bs->dirty_bitmap[chunk / (sizeof(unsigned long) * 8)] &
2506 (1 << (chunk % (sizeof(unsigned long) * 8)));
2507 } else {
2508 return 0;
2512 void bdrv_reset_dirty(BlockDriverState *bs, int64_t cur_sector,
2513 int nr_sectors)
2515 set_dirty_bitmap(bs, cur_sector, nr_sectors, 0);
2518 int64_t bdrv_get_dirty_count(BlockDriverState *bs)
2520 return bs->dirty_count;