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
24 #include "config-host.h"
25 #include "qemu-common.h"
27 #include "block_int.h"
29 #include "qemu-objects.h"
32 #include <sys/types.h>
34 #include <sys/ioctl.h>
35 #include <sys/queue.h>
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 /* The device to use for VM snapshots */
67 static BlockDriverState
*bs_snapshots
;
69 /* If non-zero, use only whitelisted block drivers */
70 static int use_bdrv_whitelist
;
72 int path_is_absolute(const char *path
)
76 /* specific case for names like: "\\.\d:" */
77 if (*path
== '/' || *path
== '\\')
80 p
= strchr(path
, ':');
86 return (*p
== '/' || *p
== '\\');
92 /* if filename is absolute, just copy it to dest. Otherwise, build a
93 path to it by considering it is relative to base_path. URL are
95 void path_combine(char *dest
, int dest_size
,
96 const char *base_path
,
104 if (path_is_absolute(filename
)) {
105 pstrcpy(dest
, dest_size
, filename
);
107 p
= strchr(base_path
, ':');
112 p1
= strrchr(base_path
, '/');
116 p2
= strrchr(base_path
, '\\');
128 if (len
> dest_size
- 1)
130 memcpy(dest
, base_path
, len
);
132 pstrcat(dest
, dest_size
, filename
);
136 void bdrv_register(BlockDriver
*bdrv
)
138 if (!bdrv
->bdrv_aio_readv
) {
139 /* add AIO emulation layer */
140 bdrv
->bdrv_aio_readv
= bdrv_aio_readv_em
;
141 bdrv
->bdrv_aio_writev
= bdrv_aio_writev_em
;
142 } else if (!bdrv
->bdrv_read
) {
143 /* add synchronous IO emulation layer */
144 bdrv
->bdrv_read
= bdrv_read_em
;
145 bdrv
->bdrv_write
= bdrv_write_em
;
148 if (!bdrv
->bdrv_aio_flush
)
149 bdrv
->bdrv_aio_flush
= bdrv_aio_flush_em
;
151 QLIST_INSERT_HEAD(&bdrv_drivers
, bdrv
, list
);
154 /* create a new block device (by default it is empty) */
155 BlockDriverState
*bdrv_new(const char *device_name
)
157 BlockDriverState
*bs
;
159 bs
= qemu_mallocz(sizeof(BlockDriverState
));
160 pstrcpy(bs
->device_name
, sizeof(bs
->device_name
), device_name
);
161 if (device_name
[0] != '\0') {
162 QTAILQ_INSERT_TAIL(&bdrv_states
, bs
, list
);
167 BlockDriver
*bdrv_find_format(const char *format_name
)
170 QLIST_FOREACH(drv1
, &bdrv_drivers
, list
) {
171 if (!strcmp(drv1
->format_name
, format_name
)) {
178 static int bdrv_is_whitelisted(BlockDriver
*drv
)
180 static const char *whitelist
[] = {
181 CONFIG_BDRV_WHITELIST
186 return 1; /* no whitelist, anything goes */
188 for (p
= whitelist
; *p
; p
++) {
189 if (!strcmp(drv
->format_name
, *p
)) {
196 BlockDriver
*bdrv_find_whitelisted_format(const char *format_name
)
198 BlockDriver
*drv
= bdrv_find_format(format_name
);
199 return drv
&& bdrv_is_whitelisted(drv
) ? drv
: NULL
;
202 int bdrv_create(BlockDriver
*drv
, const char* filename
,
203 QEMUOptionParameter
*options
)
205 if (!drv
->bdrv_create
)
208 return drv
->bdrv_create(filename
, options
);
211 int bdrv_create_file(const char* filename
, QEMUOptionParameter
*options
)
215 drv
= bdrv_find_protocol(filename
);
217 drv
= bdrv_find_format("file");
220 return bdrv_create(drv
, filename
, options
);
224 void get_tmp_filename(char *filename
, int size
)
226 char temp_dir
[MAX_PATH
];
228 GetTempPath(MAX_PATH
, temp_dir
);
229 GetTempFileName(temp_dir
, "qem", 0, filename
);
232 void get_tmp_filename(char *filename
, int size
)
236 /* XXX: race condition possible */
237 tmpdir
= getenv("TMPDIR");
240 snprintf(filename
, size
, "%s/vl.XXXXXX", tmpdir
);
241 fd
= mkstemp(filename
);
247 static int is_windows_drive_prefix(const char *filename
)
249 return (((filename
[0] >= 'a' && filename
[0] <= 'z') ||
250 (filename
[0] >= 'A' && filename
[0] <= 'Z')) &&
254 int is_windows_drive(const char *filename
)
256 if (is_windows_drive_prefix(filename
) &&
259 if (strstart(filename
, "\\\\.\\", NULL
) ||
260 strstart(filename
, "//./", NULL
))
267 * Detect host devices. By convention, /dev/cdrom[N] is always
268 * recognized as a host CDROM.
270 static BlockDriver
*find_hdev_driver(const char *filename
)
272 int score_max
= 0, score
;
273 BlockDriver
*drv
= NULL
, *d
;
275 QLIST_FOREACH(d
, &bdrv_drivers
, list
) {
276 if (d
->bdrv_probe_device
) {
277 score
= d
->bdrv_probe_device(filename
);
278 if (score
> score_max
) {
288 BlockDriver
*bdrv_find_protocol(const char *filename
)
295 /* TODO Drivers without bdrv_file_open must be specified explicitly */
298 * XXX(hch): we really should not let host device detection
299 * override an explicit protocol specification, but moving this
300 * later breaks access to device names with colons in them.
301 * Thanks to the brain-dead persistent naming schemes on udev-
302 * based Linux systems those actually are quite common.
304 drv1
= find_hdev_driver(filename
);
310 if (is_windows_drive(filename
) ||
311 is_windows_drive_prefix(filename
))
312 return bdrv_find_format("file");
315 p
= strchr(filename
, ':');
317 return bdrv_find_format("file");
320 if (len
> sizeof(protocol
) - 1)
321 len
= sizeof(protocol
) - 1;
322 memcpy(protocol
, filename
, len
);
323 protocol
[len
] = '\0';
324 QLIST_FOREACH(drv1
, &bdrv_drivers
, list
) {
325 if (drv1
->protocol_name
&&
326 !strcmp(drv1
->protocol_name
, protocol
)) {
333 static BlockDriver
*find_image_format(const char *filename
)
335 int ret
, score
, score_max
;
336 BlockDriver
*drv1
, *drv
;
338 BlockDriverState
*bs
;
340 ret
= bdrv_file_open(&bs
, filename
, 0);
344 /* Return the raw BlockDriver * to scsi-generic devices or empty drives */
345 if (bs
->sg
|| !bdrv_is_inserted(bs
)) {
347 return bdrv_find_format("raw");
350 ret
= bdrv_pread(bs
, 0, buf
, sizeof(buf
));
358 QLIST_FOREACH(drv1
, &bdrv_drivers
, list
) {
359 if (drv1
->bdrv_probe
) {
360 score
= drv1
->bdrv_probe(buf
, ret
, filename
);
361 if (score
> score_max
) {
371 * Set the current 'total_sectors' value
373 static int refresh_total_sectors(BlockDriverState
*bs
, int64_t hint
)
375 BlockDriver
*drv
= bs
->drv
;
377 /* Do not attempt drv->bdrv_getlength() on scsi-generic devices */
381 /* query actual device if possible, otherwise just trust the hint */
382 if (drv
->bdrv_getlength
) {
383 int64_t length
= drv
->bdrv_getlength(bs
);
387 hint
= length
>> BDRV_SECTOR_BITS
;
390 bs
->total_sectors
= hint
;
395 * Common part for opening disk images and files
397 static int bdrv_open_common(BlockDriverState
*bs
, const char *filename
,
398 int flags
, BlockDriver
*drv
)
405 bs
->total_sectors
= 0;
408 bs
->open_flags
= flags
;
409 /* buffer_alignment defaulted to 512, drivers can change this value */
410 bs
->buffer_alignment
= 512;
412 pstrcpy(bs
->filename
, sizeof(bs
->filename
), filename
);
414 if (use_bdrv_whitelist
&& !bdrv_is_whitelisted(drv
)) {
419 bs
->opaque
= qemu_mallocz(drv
->instance_size
);
422 * Yes, BDRV_O_NOCACHE aka O_DIRECT means we have to present a
423 * write cache to the guest. We do need the fdatasync to flush
424 * out transactions for block allocations, and we maybe have a
425 * volatile write cache in our backing device to deal with.
427 if (flags
& (BDRV_O_CACHE_WB
|BDRV_O_NOCACHE
))
428 bs
->enable_write_cache
= 1;
431 * Clear flags that are internal to the block layer before opening the
434 open_flags
= flags
& ~(BDRV_O_SNAPSHOT
| BDRV_O_NO_BACKING
);
437 * Snapshots should be writeable.
439 if (bs
->is_temporary
) {
440 open_flags
|= BDRV_O_RDWR
;
443 /* Open the image, either directly or using a protocol */
444 if (drv
->bdrv_file_open
) {
445 ret
= drv
->bdrv_file_open(bs
, filename
, open_flags
);
447 ret
= bdrv_file_open(&bs
->file
, filename
, open_flags
);
449 ret
= drv
->bdrv_open(bs
, open_flags
);
457 bs
->keep_read_only
= bs
->read_only
= !(open_flags
& BDRV_O_RDWR
);
459 ret
= refresh_total_sectors(bs
, bs
->total_sectors
);
465 if (bs
->is_temporary
) {
473 bdrv_delete(bs
->file
);
476 qemu_free(bs
->opaque
);
483 * Opens a file using a protocol (file, host_device, nbd, ...)
485 int bdrv_file_open(BlockDriverState
**pbs
, const char *filename
, int flags
)
487 BlockDriverState
*bs
;
491 drv
= bdrv_find_protocol(filename
);
497 ret
= bdrv_open_common(bs
, filename
, flags
, drv
);
508 * Opens a disk image (raw, qcow2, vmdk, ...)
510 int bdrv_open(BlockDriverState
*bs
, const char *filename
, int flags
,
515 if (flags
& BDRV_O_SNAPSHOT
) {
516 BlockDriverState
*bs1
;
519 BlockDriver
*bdrv_qcow2
;
520 QEMUOptionParameter
*options
;
521 char tmp_filename
[PATH_MAX
];
522 char backing_filename
[PATH_MAX
];
524 /* if snapshot, we create a temporary backing file and open it
525 instead of opening 'filename' directly */
527 /* if there is a backing file, use it */
529 ret
= bdrv_open(bs1
, filename
, 0, drv
);
534 total_size
= bdrv_getlength(bs1
) & BDRV_SECTOR_MASK
;
536 if (bs1
->drv
&& bs1
->drv
->protocol_name
)
541 get_tmp_filename(tmp_filename
, sizeof(tmp_filename
));
543 /* Real path is meaningless for protocols */
545 snprintf(backing_filename
, sizeof(backing_filename
),
547 else if (!realpath(filename
, backing_filename
))
550 bdrv_qcow2
= bdrv_find_format("qcow2");
551 options
= parse_option_parameters("", bdrv_qcow2
->create_options
, NULL
);
553 set_option_parameter_int(options
, BLOCK_OPT_SIZE
, total_size
);
554 set_option_parameter(options
, BLOCK_OPT_BACKING_FILE
, backing_filename
);
556 set_option_parameter(options
, BLOCK_OPT_BACKING_FMT
,
560 ret
= bdrv_create(bdrv_qcow2
, tmp_filename
, options
);
561 free_option_parameters(options
);
566 filename
= tmp_filename
;
568 bs
->is_temporary
= 1;
571 /* Find the right image format driver */
573 drv
= find_image_format(filename
);
578 goto unlink_and_fail
;
582 ret
= bdrv_open_common(bs
, filename
, flags
, drv
);
584 goto unlink_and_fail
;
587 /* If there is a backing file, use it */
588 if ((flags
& BDRV_O_NO_BACKING
) == 0 && bs
->backing_file
[0] != '\0') {
589 char backing_filename
[PATH_MAX
];
591 BlockDriver
*back_drv
= NULL
;
593 bs
->backing_hd
= bdrv_new("");
594 path_combine(backing_filename
, sizeof(backing_filename
),
595 filename
, bs
->backing_file
);
596 if (bs
->backing_format
[0] != '\0')
597 back_drv
= bdrv_find_format(bs
->backing_format
);
599 /* backing files always opened read-only */
601 flags
& ~(BDRV_O_RDWR
| BDRV_O_SNAPSHOT
| BDRV_O_NO_BACKING
);
603 ret
= bdrv_open(bs
->backing_hd
, backing_filename
, back_flags
, back_drv
);
608 if (bs
->is_temporary
) {
609 bs
->backing_hd
->keep_read_only
= !(flags
& BDRV_O_RDWR
);
611 /* base image inherits from "parent" */
612 bs
->backing_hd
->keep_read_only
= bs
->keep_read_only
;
616 if (!bdrv_key_required(bs
)) {
617 /* call the change callback */
618 bs
->media_changed
= 1;
620 bs
->change_cb(bs
->change_opaque
);
626 if (bs
->is_temporary
) {
632 void bdrv_close(BlockDriverState
*bs
)
635 if (bs
== bs_snapshots
) {
638 if (bs
->backing_hd
) {
639 bdrv_delete(bs
->backing_hd
);
640 bs
->backing_hd
= NULL
;
642 bs
->drv
->bdrv_close(bs
);
643 qemu_free(bs
->opaque
);
645 if (bs
->is_temporary
) {
646 unlink(bs
->filename
);
652 if (bs
->file
!= NULL
) {
653 bdrv_close(bs
->file
);
656 /* call the change callback */
657 bs
->media_changed
= 1;
659 bs
->change_cb(bs
->change_opaque
);
663 void bdrv_close_all(void)
665 BlockDriverState
*bs
;
667 QTAILQ_FOREACH(bs
, &bdrv_states
, list
) {
672 void bdrv_delete(BlockDriverState
*bs
)
676 /* remove from list, if necessary */
677 if (bs
->device_name
[0] != '\0') {
678 QTAILQ_REMOVE(&bdrv_states
, bs
, list
);
682 if (bs
->file
!= NULL
) {
683 bdrv_delete(bs
->file
);
686 assert(bs
!= bs_snapshots
);
690 int bdrv_attach(BlockDriverState
*bs
, DeviceState
*qdev
)
699 void bdrv_detach(BlockDriverState
*bs
, DeviceState
*qdev
)
701 assert(bs
->peer
== qdev
);
705 DeviceState
*bdrv_get_attached(BlockDriverState
*bs
)
711 * Run consistency checks on an image
713 * Returns 0 if the check could be completed (it doesn't mean that the image is
714 * free of errors) or -errno when an internal error occured. The results of the
715 * check are stored in res.
717 int bdrv_check(BlockDriverState
*bs
, BdrvCheckResult
*res
)
719 if (bs
->drv
->bdrv_check
== NULL
) {
723 memset(res
, 0, sizeof(*res
));
724 res
->corruptions
= bs
->drv
->bdrv_check(bs
);
725 return res
->corruptions
< 0 ? res
->corruptions
: 0;
728 /* commit COW file into the raw image */
729 int bdrv_commit(BlockDriverState
*bs
)
731 BlockDriver
*drv
= bs
->drv
;
732 int64_t i
, total_sectors
;
733 int n
, j
, ro
, open_flags
;
734 int ret
= 0, rw_ret
= 0;
735 unsigned char sector
[BDRV_SECTOR_SIZE
];
737 BlockDriverState
*bs_rw
, *bs_ro
;
742 if (!bs
->backing_hd
) {
746 if (bs
->backing_hd
->keep_read_only
) {
750 ro
= bs
->backing_hd
->read_only
;
751 strncpy(filename
, bs
->backing_hd
->filename
, sizeof(filename
));
752 open_flags
= bs
->backing_hd
->open_flags
;
756 bdrv_delete(bs
->backing_hd
);
757 bs
->backing_hd
= NULL
;
758 bs_rw
= bdrv_new("");
759 rw_ret
= bdrv_open(bs_rw
, filename
, open_flags
| BDRV_O_RDWR
, drv
);
762 /* try to re-open read-only */
763 bs_ro
= bdrv_new("");
764 ret
= bdrv_open(bs_ro
, filename
, open_flags
& ~BDRV_O_RDWR
, drv
);
767 /* drive not functional anymore */
771 bs
->backing_hd
= bs_ro
;
774 bs
->backing_hd
= bs_rw
;
777 total_sectors
= bdrv_getlength(bs
) >> BDRV_SECTOR_BITS
;
778 for (i
= 0; i
< total_sectors
;) {
779 if (drv
->bdrv_is_allocated(bs
, i
, 65536, &n
)) {
780 for(j
= 0; j
< n
; j
++) {
781 if (bdrv_read(bs
, i
, sector
, 1) != 0) {
786 if (bdrv_write(bs
->backing_hd
, i
, sector
, 1) != 0) {
797 if (drv
->bdrv_make_empty
) {
798 ret
= drv
->bdrv_make_empty(bs
);
803 * Make sure all data we wrote to the backing device is actually
807 bdrv_flush(bs
->backing_hd
);
813 bdrv_delete(bs
->backing_hd
);
814 bs
->backing_hd
= NULL
;
815 bs_ro
= bdrv_new("");
816 ret
= bdrv_open(bs_ro
, filename
, open_flags
& ~BDRV_O_RDWR
, drv
);
819 /* drive not functional anymore */
823 bs
->backing_hd
= bs_ro
;
824 bs
->backing_hd
->keep_read_only
= 0;
830 void bdrv_commit_all(void)
832 BlockDriverState
*bs
;
834 QTAILQ_FOREACH(bs
, &bdrv_states
, list
) {
842 * -EINVAL - backing format specified, but no file
843 * -ENOSPC - can't update the backing file because no space is left in the
845 * -ENOTSUP - format driver doesn't support changing the backing file
847 int bdrv_change_backing_file(BlockDriverState
*bs
,
848 const char *backing_file
, const char *backing_fmt
)
850 BlockDriver
*drv
= bs
->drv
;
852 if (drv
->bdrv_change_backing_file
!= NULL
) {
853 return drv
->bdrv_change_backing_file(bs
, backing_file
, backing_fmt
);
859 static int bdrv_check_byte_request(BlockDriverState
*bs
, int64_t offset
,
864 if (!bdrv_is_inserted(bs
))
870 len
= bdrv_getlength(bs
);
875 if ((offset
> len
) || (len
- offset
< size
))
881 static int bdrv_check_request(BlockDriverState
*bs
, int64_t sector_num
,
884 return bdrv_check_byte_request(bs
, sector_num
* BDRV_SECTOR_SIZE
,
885 nb_sectors
* BDRV_SECTOR_SIZE
);
888 /* return < 0 if error. See bdrv_write() for the return codes */
889 int bdrv_read(BlockDriverState
*bs
, int64_t sector_num
,
890 uint8_t *buf
, int nb_sectors
)
892 BlockDriver
*drv
= bs
->drv
;
896 if (bdrv_check_request(bs
, sector_num
, nb_sectors
))
899 return drv
->bdrv_read(bs
, sector_num
, buf
, nb_sectors
);
902 static void set_dirty_bitmap(BlockDriverState
*bs
, int64_t sector_num
,
903 int nb_sectors
, int dirty
)
906 unsigned long val
, idx
, bit
;
908 start
= sector_num
/ BDRV_SECTORS_PER_DIRTY_CHUNK
;
909 end
= (sector_num
+ nb_sectors
- 1) / BDRV_SECTORS_PER_DIRTY_CHUNK
;
911 for (; start
<= end
; start
++) {
912 idx
= start
/ (sizeof(unsigned long) * 8);
913 bit
= start
% (sizeof(unsigned long) * 8);
914 val
= bs
->dirty_bitmap
[idx
];
916 if (!(val
& (1 << bit
))) {
921 if (val
& (1 << bit
)) {
926 bs
->dirty_bitmap
[idx
] = val
;
930 /* Return < 0 if error. Important errors are:
931 -EIO generic I/O error (may happen for all errors)
932 -ENOMEDIUM No media inserted.
933 -EINVAL Invalid sector number or nb_sectors
934 -EACCES Trying to write a read-only device
936 int bdrv_write(BlockDriverState
*bs
, int64_t sector_num
,
937 const uint8_t *buf
, int nb_sectors
)
939 BlockDriver
*drv
= bs
->drv
;
944 if (bdrv_check_request(bs
, sector_num
, nb_sectors
))
947 if (bs
->dirty_bitmap
) {
948 set_dirty_bitmap(bs
, sector_num
, nb_sectors
, 1);
951 if (bs
->wr_highest_sector
< sector_num
+ nb_sectors
- 1) {
952 bs
->wr_highest_sector
= sector_num
+ nb_sectors
- 1;
955 return drv
->bdrv_write(bs
, sector_num
, buf
, nb_sectors
);
958 int bdrv_pread(BlockDriverState
*bs
, int64_t offset
,
959 void *buf
, int count1
)
961 uint8_t tmp_buf
[BDRV_SECTOR_SIZE
];
962 int len
, nb_sectors
, count
;
967 /* first read to align to sector start */
968 len
= (BDRV_SECTOR_SIZE
- offset
) & (BDRV_SECTOR_SIZE
- 1);
971 sector_num
= offset
>> BDRV_SECTOR_BITS
;
973 if ((ret
= bdrv_read(bs
, sector_num
, tmp_buf
, 1)) < 0)
975 memcpy(buf
, tmp_buf
+ (offset
& (BDRV_SECTOR_SIZE
- 1)), len
);
983 /* read the sectors "in place" */
984 nb_sectors
= count
>> BDRV_SECTOR_BITS
;
985 if (nb_sectors
> 0) {
986 if ((ret
= bdrv_read(bs
, sector_num
, buf
, nb_sectors
)) < 0)
988 sector_num
+= nb_sectors
;
989 len
= nb_sectors
<< BDRV_SECTOR_BITS
;
994 /* add data from the last sector */
996 if ((ret
= bdrv_read(bs
, sector_num
, tmp_buf
, 1)) < 0)
998 memcpy(buf
, tmp_buf
, count
);
1003 int bdrv_pwrite(BlockDriverState
*bs
, int64_t offset
,
1004 const void *buf
, int count1
)
1006 uint8_t tmp_buf
[BDRV_SECTOR_SIZE
];
1007 int len
, nb_sectors
, count
;
1012 /* first write to align to sector start */
1013 len
= (BDRV_SECTOR_SIZE
- offset
) & (BDRV_SECTOR_SIZE
- 1);
1016 sector_num
= offset
>> BDRV_SECTOR_BITS
;
1018 if ((ret
= bdrv_read(bs
, sector_num
, tmp_buf
, 1)) < 0)
1020 memcpy(tmp_buf
+ (offset
& (BDRV_SECTOR_SIZE
- 1)), buf
, len
);
1021 if ((ret
= bdrv_write(bs
, sector_num
, tmp_buf
, 1)) < 0)
1030 /* write the sectors "in place" */
1031 nb_sectors
= count
>> BDRV_SECTOR_BITS
;
1032 if (nb_sectors
> 0) {
1033 if ((ret
= bdrv_write(bs
, sector_num
, buf
, nb_sectors
)) < 0)
1035 sector_num
+= nb_sectors
;
1036 len
= nb_sectors
<< BDRV_SECTOR_BITS
;
1041 /* add data from the last sector */
1043 if ((ret
= bdrv_read(bs
, sector_num
, tmp_buf
, 1)) < 0)
1045 memcpy(tmp_buf
, buf
, count
);
1046 if ((ret
= bdrv_write(bs
, sector_num
, tmp_buf
, 1)) < 0)
1053 * Writes to the file and ensures that no writes are reordered across this
1054 * request (acts as a barrier)
1056 * Returns 0 on success, -errno in error cases.
1058 int bdrv_pwrite_sync(BlockDriverState
*bs
, int64_t offset
,
1059 const void *buf
, int count
)
1063 ret
= bdrv_pwrite(bs
, offset
, buf
, count
);
1068 /* No flush needed for cache=writethrough, it uses O_DSYNC */
1069 if ((bs
->open_flags
& BDRV_O_CACHE_MASK
) != 0) {
1077 * Writes to the file and ensures that no writes are reordered across this
1078 * request (acts as a barrier)
1080 * Returns 0 on success, -errno in error cases.
1082 int bdrv_write_sync(BlockDriverState
*bs
, int64_t sector_num
,
1083 const uint8_t *buf
, int nb_sectors
)
1085 return bdrv_pwrite_sync(bs
, BDRV_SECTOR_SIZE
* sector_num
,
1086 buf
, BDRV_SECTOR_SIZE
* nb_sectors
);
1090 * Truncate file to 'offset' bytes (needed only for file protocols)
1092 int bdrv_truncate(BlockDriverState
*bs
, int64_t offset
)
1094 BlockDriver
*drv
= bs
->drv
;
1098 if (!drv
->bdrv_truncate
)
1102 ret
= drv
->bdrv_truncate(bs
, offset
);
1104 ret
= refresh_total_sectors(bs
, offset
>> BDRV_SECTOR_BITS
);
1110 * Length of a file in bytes. Return < 0 if error or unknown.
1112 int64_t bdrv_getlength(BlockDriverState
*bs
)
1114 BlockDriver
*drv
= bs
->drv
;
1118 /* Fixed size devices use the total_sectors value for speed instead of
1119 issuing a length query (like lseek) on each call. Also, legacy block
1120 drivers don't provide a bdrv_getlength function and must use
1122 if (!bs
->growable
|| !drv
->bdrv_getlength
) {
1123 return bs
->total_sectors
* BDRV_SECTOR_SIZE
;
1125 return drv
->bdrv_getlength(bs
);
1128 /* return 0 as number of sectors if no device present or error */
1129 void bdrv_get_geometry(BlockDriverState
*bs
, uint64_t *nb_sectors_ptr
)
1132 length
= bdrv_getlength(bs
);
1136 length
= length
>> BDRV_SECTOR_BITS
;
1137 *nb_sectors_ptr
= length
;
1141 uint8_t boot_ind
; /* 0x80 - active */
1142 uint8_t head
; /* starting head */
1143 uint8_t sector
; /* starting sector */
1144 uint8_t cyl
; /* starting cylinder */
1145 uint8_t sys_ind
; /* What partition type */
1146 uint8_t end_head
; /* end head */
1147 uint8_t end_sector
; /* end sector */
1148 uint8_t end_cyl
; /* end cylinder */
1149 uint32_t start_sect
; /* starting sector counting from 0 */
1150 uint32_t nr_sects
; /* nr of sectors in partition */
1151 } __attribute__((packed
));
1153 /* try to guess the disk logical geometry from the MSDOS partition table. Return 0 if OK, -1 if could not guess */
1154 static int guess_disk_lchs(BlockDriverState
*bs
,
1155 int *pcylinders
, int *pheads
, int *psectors
)
1157 uint8_t buf
[BDRV_SECTOR_SIZE
];
1158 int ret
, i
, heads
, sectors
, cylinders
;
1159 struct partition
*p
;
1161 uint64_t nb_sectors
;
1163 bdrv_get_geometry(bs
, &nb_sectors
);
1165 ret
= bdrv_read(bs
, 0, buf
, 1);
1168 /* test msdos magic */
1169 if (buf
[510] != 0x55 || buf
[511] != 0xaa)
1171 for(i
= 0; i
< 4; i
++) {
1172 p
= ((struct partition
*)(buf
+ 0x1be)) + i
;
1173 nr_sects
= le32_to_cpu(p
->nr_sects
);
1174 if (nr_sects
&& p
->end_head
) {
1175 /* We make the assumption that the partition terminates on
1176 a cylinder boundary */
1177 heads
= p
->end_head
+ 1;
1178 sectors
= p
->end_sector
& 63;
1181 cylinders
= nb_sectors
/ (heads
* sectors
);
1182 if (cylinders
< 1 || cylinders
> 16383)
1185 *psectors
= sectors
;
1186 *pcylinders
= cylinders
;
1188 printf("guessed geometry: LCHS=%d %d %d\n",
1189 cylinders
, heads
, sectors
);
1197 void bdrv_guess_geometry(BlockDriverState
*bs
, int *pcyls
, int *pheads
, int *psecs
)
1199 int translation
, lba_detected
= 0;
1200 int cylinders
, heads
, secs
;
1201 uint64_t nb_sectors
;
1203 /* if a geometry hint is available, use it */
1204 bdrv_get_geometry(bs
, &nb_sectors
);
1205 bdrv_get_geometry_hint(bs
, &cylinders
, &heads
, &secs
);
1206 translation
= bdrv_get_translation_hint(bs
);
1207 if (cylinders
!= 0) {
1212 if (guess_disk_lchs(bs
, &cylinders
, &heads
, &secs
) == 0) {
1214 /* if heads > 16, it means that a BIOS LBA
1215 translation was active, so the default
1216 hardware geometry is OK */
1218 goto default_geometry
;
1223 /* disable any translation to be in sync with
1224 the logical geometry */
1225 if (translation
== BIOS_ATA_TRANSLATION_AUTO
) {
1226 bdrv_set_translation_hint(bs
,
1227 BIOS_ATA_TRANSLATION_NONE
);
1232 /* if no geometry, use a standard physical disk geometry */
1233 cylinders
= nb_sectors
/ (16 * 63);
1235 if (cylinders
> 16383)
1237 else if (cylinders
< 2)
1242 if ((lba_detected
== 1) && (translation
== BIOS_ATA_TRANSLATION_AUTO
)) {
1243 if ((*pcyls
* *pheads
) <= 131072) {
1244 bdrv_set_translation_hint(bs
,
1245 BIOS_ATA_TRANSLATION_LARGE
);
1247 bdrv_set_translation_hint(bs
,
1248 BIOS_ATA_TRANSLATION_LBA
);
1252 bdrv_set_geometry_hint(bs
, *pcyls
, *pheads
, *psecs
);
1256 void bdrv_set_geometry_hint(BlockDriverState
*bs
,
1257 int cyls
, int heads
, int secs
)
1264 void bdrv_set_type_hint(BlockDriverState
*bs
, int type
)
1267 bs
->removable
= ((type
== BDRV_TYPE_CDROM
||
1268 type
== BDRV_TYPE_FLOPPY
));
1271 void bdrv_set_translation_hint(BlockDriverState
*bs
, int translation
)
1273 bs
->translation
= translation
;
1276 void bdrv_get_geometry_hint(BlockDriverState
*bs
,
1277 int *pcyls
, int *pheads
, int *psecs
)
1280 *pheads
= bs
->heads
;
1284 int bdrv_get_type_hint(BlockDriverState
*bs
)
1289 int bdrv_get_translation_hint(BlockDriverState
*bs
)
1291 return bs
->translation
;
1294 void bdrv_set_on_error(BlockDriverState
*bs
, BlockErrorAction on_read_error
,
1295 BlockErrorAction on_write_error
)
1297 bs
->on_read_error
= on_read_error
;
1298 bs
->on_write_error
= on_write_error
;
1301 BlockErrorAction
bdrv_get_on_error(BlockDriverState
*bs
, int is_read
)
1303 return is_read
? bs
->on_read_error
: bs
->on_write_error
;
1306 void bdrv_set_removable(BlockDriverState
*bs
, int removable
)
1308 bs
->removable
= removable
;
1309 if (removable
&& bs
== bs_snapshots
) {
1310 bs_snapshots
= NULL
;
1314 int bdrv_is_removable(BlockDriverState
*bs
)
1316 return bs
->removable
;
1319 int bdrv_is_read_only(BlockDriverState
*bs
)
1321 return bs
->read_only
;
1324 int bdrv_is_sg(BlockDriverState
*bs
)
1329 int bdrv_enable_write_cache(BlockDriverState
*bs
)
1331 return bs
->enable_write_cache
;
1334 /* XXX: no longer used */
1335 void bdrv_set_change_cb(BlockDriverState
*bs
,
1336 void (*change_cb
)(void *opaque
), void *opaque
)
1338 bs
->change_cb
= change_cb
;
1339 bs
->change_opaque
= opaque
;
1342 int bdrv_is_encrypted(BlockDriverState
*bs
)
1344 if (bs
->backing_hd
&& bs
->backing_hd
->encrypted
)
1346 return bs
->encrypted
;
1349 int bdrv_key_required(BlockDriverState
*bs
)
1351 BlockDriverState
*backing_hd
= bs
->backing_hd
;
1353 if (backing_hd
&& backing_hd
->encrypted
&& !backing_hd
->valid_key
)
1355 return (bs
->encrypted
&& !bs
->valid_key
);
1358 int bdrv_set_key(BlockDriverState
*bs
, const char *key
)
1361 if (bs
->backing_hd
&& bs
->backing_hd
->encrypted
) {
1362 ret
= bdrv_set_key(bs
->backing_hd
, key
);
1368 if (!bs
->encrypted
) {
1370 } else if (!bs
->drv
|| !bs
->drv
->bdrv_set_key
) {
1373 ret
= bs
->drv
->bdrv_set_key(bs
, key
);
1376 } else if (!bs
->valid_key
) {
1378 /* call the change callback now, we skipped it on open */
1379 bs
->media_changed
= 1;
1381 bs
->change_cb(bs
->change_opaque
);
1386 void bdrv_get_format(BlockDriverState
*bs
, char *buf
, int buf_size
)
1391 pstrcpy(buf
, buf_size
, bs
->drv
->format_name
);
1395 void bdrv_iterate_format(void (*it
)(void *opaque
, const char *name
),
1400 QLIST_FOREACH(drv
, &bdrv_drivers
, list
) {
1401 it(opaque
, drv
->format_name
);
1405 BlockDriverState
*bdrv_find(const char *name
)
1407 BlockDriverState
*bs
;
1409 QTAILQ_FOREACH(bs
, &bdrv_states
, list
) {
1410 if (!strcmp(name
, bs
->device_name
)) {
1417 BlockDriverState
*bdrv_next(BlockDriverState
*bs
)
1420 return QTAILQ_FIRST(&bdrv_states
);
1422 return QTAILQ_NEXT(bs
, list
);
1425 void bdrv_iterate(void (*it
)(void *opaque
, BlockDriverState
*bs
), void *opaque
)
1427 BlockDriverState
*bs
;
1429 QTAILQ_FOREACH(bs
, &bdrv_states
, list
) {
1434 const char *bdrv_get_device_name(BlockDriverState
*bs
)
1436 return bs
->device_name
;
1439 void bdrv_flush(BlockDriverState
*bs
)
1441 if (bs
->open_flags
& BDRV_O_NO_FLUSH
) {
1445 if (bs
->drv
&& bs
->drv
->bdrv_flush
)
1446 bs
->drv
->bdrv_flush(bs
);
1449 void bdrv_flush_all(void)
1451 BlockDriverState
*bs
;
1453 QTAILQ_FOREACH(bs
, &bdrv_states
, list
) {
1454 if (bs
->drv
&& !bdrv_is_read_only(bs
) &&
1455 (!bdrv_is_removable(bs
) || bdrv_is_inserted(bs
))) {
1461 int bdrv_has_zero_init(BlockDriverState
*bs
)
1465 if (bs
->drv
->no_zero_init
) {
1467 } else if (bs
->file
) {
1468 return bdrv_has_zero_init(bs
->file
);
1475 * Returns true iff the specified sector is present in the disk image. Drivers
1476 * not implementing the functionality are assumed to not support backing files,
1477 * hence all their sectors are reported as allocated.
1479 * 'pnum' is set to the number of sectors (including and immediately following
1480 * the specified sector) that are known to be in the same
1481 * allocated/unallocated state.
1483 * 'nb_sectors' is the max value 'pnum' should be set to.
1485 int bdrv_is_allocated(BlockDriverState
*bs
, int64_t sector_num
, int nb_sectors
,
1489 if (!bs
->drv
->bdrv_is_allocated
) {
1490 if (sector_num
>= bs
->total_sectors
) {
1494 n
= bs
->total_sectors
- sector_num
;
1495 *pnum
= (n
< nb_sectors
) ? (n
) : (nb_sectors
);
1498 return bs
->drv
->bdrv_is_allocated(bs
, sector_num
, nb_sectors
, pnum
);
1501 void bdrv_mon_event(const BlockDriverState
*bdrv
,
1502 BlockMonEventAction action
, int is_read
)
1505 const char *action_str
;
1508 case BDRV_ACTION_REPORT
:
1509 action_str
= "report";
1511 case BDRV_ACTION_IGNORE
:
1512 action_str
= "ignore";
1514 case BDRV_ACTION_STOP
:
1515 action_str
= "stop";
1521 data
= qobject_from_jsonf("{ 'device': %s, 'action': %s, 'operation': %s }",
1524 is_read
? "read" : "write");
1525 monitor_protocol_event(QEVENT_BLOCK_IO_ERROR
, data
);
1527 qobject_decref(data
);
1530 static void bdrv_print_dict(QObject
*obj
, void *opaque
)
1533 Monitor
*mon
= opaque
;
1535 bs_dict
= qobject_to_qdict(obj
);
1537 monitor_printf(mon
, "%s: type=%s removable=%d",
1538 qdict_get_str(bs_dict
, "device"),
1539 qdict_get_str(bs_dict
, "type"),
1540 qdict_get_bool(bs_dict
, "removable"));
1542 if (qdict_get_bool(bs_dict
, "removable")) {
1543 monitor_printf(mon
, " locked=%d", qdict_get_bool(bs_dict
, "locked"));
1546 if (qdict_haskey(bs_dict
, "inserted")) {
1547 QDict
*qdict
= qobject_to_qdict(qdict_get(bs_dict
, "inserted"));
1549 monitor_printf(mon
, " file=");
1550 monitor_print_filename(mon
, qdict_get_str(qdict
, "file"));
1551 if (qdict_haskey(qdict
, "backing_file")) {
1552 monitor_printf(mon
, " backing_file=");
1553 monitor_print_filename(mon
, qdict_get_str(qdict
, "backing_file"));
1555 monitor_printf(mon
, " ro=%d drv=%s encrypted=%d",
1556 qdict_get_bool(qdict
, "ro"),
1557 qdict_get_str(qdict
, "drv"),
1558 qdict_get_bool(qdict
, "encrypted"));
1560 monitor_printf(mon
, " [not inserted]");
1563 monitor_printf(mon
, "\n");
1566 void bdrv_info_print(Monitor
*mon
, const QObject
*data
)
1568 qlist_iter(qobject_to_qlist(data
), bdrv_print_dict
, mon
);
1571 void bdrv_info(Monitor
*mon
, QObject
**ret_data
)
1574 BlockDriverState
*bs
;
1576 bs_list
= qlist_new();
1578 QTAILQ_FOREACH(bs
, &bdrv_states
, list
) {
1580 const char *type
= "unknown";
1586 case BDRV_TYPE_CDROM
:
1589 case BDRV_TYPE_FLOPPY
:
1594 bs_obj
= qobject_from_jsonf("{ 'device': %s, 'type': %s, "
1595 "'removable': %i, 'locked': %i }",
1596 bs
->device_name
, type
, bs
->removable
,
1601 QDict
*bs_dict
= qobject_to_qdict(bs_obj
);
1603 obj
= qobject_from_jsonf("{ 'file': %s, 'ro': %i, 'drv': %s, "
1604 "'encrypted': %i }",
1605 bs
->filename
, bs
->read_only
,
1606 bs
->drv
->format_name
,
1607 bdrv_is_encrypted(bs
));
1608 if (bs
->backing_file
[0] != '\0') {
1609 QDict
*qdict
= qobject_to_qdict(obj
);
1610 qdict_put(qdict
, "backing_file",
1611 qstring_from_str(bs
->backing_file
));
1614 qdict_put_obj(bs_dict
, "inserted", obj
);
1616 qlist_append_obj(bs_list
, bs_obj
);
1619 *ret_data
= QOBJECT(bs_list
);
1622 static void bdrv_stats_iter(QObject
*data
, void *opaque
)
1625 Monitor
*mon
= opaque
;
1627 qdict
= qobject_to_qdict(data
);
1628 monitor_printf(mon
, "%s:", qdict_get_str(qdict
, "device"));
1630 qdict
= qobject_to_qdict(qdict_get(qdict
, "stats"));
1631 monitor_printf(mon
, " rd_bytes=%" PRId64
1632 " wr_bytes=%" PRId64
1633 " rd_operations=%" PRId64
1634 " wr_operations=%" PRId64
1636 qdict_get_int(qdict
, "rd_bytes"),
1637 qdict_get_int(qdict
, "wr_bytes"),
1638 qdict_get_int(qdict
, "rd_operations"),
1639 qdict_get_int(qdict
, "wr_operations"));
1642 void bdrv_stats_print(Monitor
*mon
, const QObject
*data
)
1644 qlist_iter(qobject_to_qlist(data
), bdrv_stats_iter
, mon
);
1647 static QObject
* bdrv_info_stats_bs(BlockDriverState
*bs
)
1652 res
= qobject_from_jsonf("{ 'stats': {"
1653 "'rd_bytes': %" PRId64
","
1654 "'wr_bytes': %" PRId64
","
1655 "'rd_operations': %" PRId64
","
1656 "'wr_operations': %" PRId64
","
1657 "'wr_highest_offset': %" PRId64
1659 bs
->rd_bytes
, bs
->wr_bytes
,
1660 bs
->rd_ops
, bs
->wr_ops
,
1661 bs
->wr_highest_sector
*
1662 (uint64_t)BDRV_SECTOR_SIZE
);
1663 dict
= qobject_to_qdict(res
);
1665 if (*bs
->device_name
) {
1666 qdict_put(dict
, "device", qstring_from_str(bs
->device_name
));
1670 QObject
*parent
= bdrv_info_stats_bs(bs
->file
);
1671 qdict_put_obj(dict
, "parent", parent
);
1677 void bdrv_info_stats(Monitor
*mon
, QObject
**ret_data
)
1681 BlockDriverState
*bs
;
1683 devices
= qlist_new();
1685 QTAILQ_FOREACH(bs
, &bdrv_states
, list
) {
1686 obj
= bdrv_info_stats_bs(bs
);
1687 qlist_append_obj(devices
, obj
);
1690 *ret_data
= QOBJECT(devices
);
1693 const char *bdrv_get_encrypted_filename(BlockDriverState
*bs
)
1695 if (bs
->backing_hd
&& bs
->backing_hd
->encrypted
)
1696 return bs
->backing_file
;
1697 else if (bs
->encrypted
)
1698 return bs
->filename
;
1703 void bdrv_get_backing_filename(BlockDriverState
*bs
,
1704 char *filename
, int filename_size
)
1706 if (!bs
->backing_file
) {
1707 pstrcpy(filename
, filename_size
, "");
1709 pstrcpy(filename
, filename_size
, bs
->backing_file
);
1713 int bdrv_write_compressed(BlockDriverState
*bs
, int64_t sector_num
,
1714 const uint8_t *buf
, int nb_sectors
)
1716 BlockDriver
*drv
= bs
->drv
;
1719 if (!drv
->bdrv_write_compressed
)
1721 if (bdrv_check_request(bs
, sector_num
, nb_sectors
))
1724 if (bs
->dirty_bitmap
) {
1725 set_dirty_bitmap(bs
, sector_num
, nb_sectors
, 1);
1728 return drv
->bdrv_write_compressed(bs
, sector_num
, buf
, nb_sectors
);
1731 int bdrv_get_info(BlockDriverState
*bs
, BlockDriverInfo
*bdi
)
1733 BlockDriver
*drv
= bs
->drv
;
1736 if (!drv
->bdrv_get_info
)
1738 memset(bdi
, 0, sizeof(*bdi
));
1739 return drv
->bdrv_get_info(bs
, bdi
);
1742 int bdrv_save_vmstate(BlockDriverState
*bs
, const uint8_t *buf
,
1743 int64_t pos
, int size
)
1745 BlockDriver
*drv
= bs
->drv
;
1748 if (drv
->bdrv_save_vmstate
)
1749 return drv
->bdrv_save_vmstate(bs
, buf
, pos
, size
);
1751 return bdrv_save_vmstate(bs
->file
, buf
, pos
, size
);
1755 int bdrv_load_vmstate(BlockDriverState
*bs
, uint8_t *buf
,
1756 int64_t pos
, int size
)
1758 BlockDriver
*drv
= bs
->drv
;
1761 if (drv
->bdrv_load_vmstate
)
1762 return drv
->bdrv_load_vmstate(bs
, buf
, pos
, size
);
1764 return bdrv_load_vmstate(bs
->file
, buf
, pos
, size
);
1768 void bdrv_debug_event(BlockDriverState
*bs
, BlkDebugEvent event
)
1770 BlockDriver
*drv
= bs
->drv
;
1772 if (!drv
|| !drv
->bdrv_debug_event
) {
1776 return drv
->bdrv_debug_event(bs
, event
);
1780 /**************************************************************/
1781 /* handling of snapshots */
1783 int bdrv_can_snapshot(BlockDriverState
*bs
)
1785 BlockDriver
*drv
= bs
->drv
;
1786 if (!drv
|| bdrv_is_removable(bs
) || bdrv_is_read_only(bs
)) {
1790 if (!drv
->bdrv_snapshot_create
) {
1791 if (bs
->file
!= NULL
) {
1792 return bdrv_can_snapshot(bs
->file
);
1800 BlockDriverState
*bdrv_snapshots(void)
1802 BlockDriverState
*bs
;
1805 return bs_snapshots
;
1809 while ((bs
= bdrv_next(bs
))) {
1810 if (bdrv_can_snapshot(bs
)) {
1818 int bdrv_snapshot_create(BlockDriverState
*bs
,
1819 QEMUSnapshotInfo
*sn_info
)
1821 BlockDriver
*drv
= bs
->drv
;
1824 if (drv
->bdrv_snapshot_create
)
1825 return drv
->bdrv_snapshot_create(bs
, sn_info
);
1827 return bdrv_snapshot_create(bs
->file
, sn_info
);
1831 int bdrv_snapshot_goto(BlockDriverState
*bs
,
1832 const char *snapshot_id
)
1834 BlockDriver
*drv
= bs
->drv
;
1839 if (drv
->bdrv_snapshot_goto
)
1840 return drv
->bdrv_snapshot_goto(bs
, snapshot_id
);
1843 drv
->bdrv_close(bs
);
1844 ret
= bdrv_snapshot_goto(bs
->file
, snapshot_id
);
1845 open_ret
= drv
->bdrv_open(bs
, bs
->open_flags
);
1847 bdrv_delete(bs
->file
);
1857 int bdrv_snapshot_delete(BlockDriverState
*bs
, const char *snapshot_id
)
1859 BlockDriver
*drv
= bs
->drv
;
1862 if (drv
->bdrv_snapshot_delete
)
1863 return drv
->bdrv_snapshot_delete(bs
, snapshot_id
);
1865 return bdrv_snapshot_delete(bs
->file
, snapshot_id
);
1869 int bdrv_snapshot_list(BlockDriverState
*bs
,
1870 QEMUSnapshotInfo
**psn_info
)
1872 BlockDriver
*drv
= bs
->drv
;
1875 if (drv
->bdrv_snapshot_list
)
1876 return drv
->bdrv_snapshot_list(bs
, psn_info
);
1878 return bdrv_snapshot_list(bs
->file
, psn_info
);
1882 #define NB_SUFFIXES 4
1884 char *get_human_readable_size(char *buf
, int buf_size
, int64_t size
)
1886 static const char suffixes
[NB_SUFFIXES
] = "KMGT";
1891 snprintf(buf
, buf_size
, "%" PRId64
, size
);
1894 for(i
= 0; i
< NB_SUFFIXES
; i
++) {
1895 if (size
< (10 * base
)) {
1896 snprintf(buf
, buf_size
, "%0.1f%c",
1897 (double)size
/ base
,
1900 } else if (size
< (1000 * base
) || i
== (NB_SUFFIXES
- 1)) {
1901 snprintf(buf
, buf_size
, "%" PRId64
"%c",
1902 ((size
+ (base
>> 1)) / base
),
1912 char *bdrv_snapshot_dump(char *buf
, int buf_size
, QEMUSnapshotInfo
*sn
)
1914 char buf1
[128], date_buf
[128], clock_buf
[128];
1924 snprintf(buf
, buf_size
,
1925 "%-10s%-20s%7s%20s%15s",
1926 "ID", "TAG", "VM SIZE", "DATE", "VM CLOCK");
1930 ptm
= localtime(&ti
);
1931 strftime(date_buf
, sizeof(date_buf
),
1932 "%Y-%m-%d %H:%M:%S", ptm
);
1934 localtime_r(&ti
, &tm
);
1935 strftime(date_buf
, sizeof(date_buf
),
1936 "%Y-%m-%d %H:%M:%S", &tm
);
1938 secs
= sn
->vm_clock_nsec
/ 1000000000;
1939 snprintf(clock_buf
, sizeof(clock_buf
),
1940 "%02d:%02d:%02d.%03d",
1942 (int)((secs
/ 60) % 60),
1944 (int)((sn
->vm_clock_nsec
/ 1000000) % 1000));
1945 snprintf(buf
, buf_size
,
1946 "%-10s%-20s%7s%20s%15s",
1947 sn
->id_str
, sn
->name
,
1948 get_human_readable_size(buf1
, sizeof(buf1
), sn
->vm_state_size
),
1956 /**************************************************************/
1959 BlockDriverAIOCB
*bdrv_aio_readv(BlockDriverState
*bs
, int64_t sector_num
,
1960 QEMUIOVector
*qiov
, int nb_sectors
,
1961 BlockDriverCompletionFunc
*cb
, void *opaque
)
1963 BlockDriver
*drv
= bs
->drv
;
1964 BlockDriverAIOCB
*ret
;
1968 if (bdrv_check_request(bs
, sector_num
, nb_sectors
))
1971 ret
= drv
->bdrv_aio_readv(bs
, sector_num
, qiov
, nb_sectors
,
1975 /* Update stats even though technically transfer has not happened. */
1976 bs
->rd_bytes
+= (unsigned) nb_sectors
* BDRV_SECTOR_SIZE
;
1983 BlockDriverAIOCB
*bdrv_aio_writev(BlockDriverState
*bs
, int64_t sector_num
,
1984 QEMUIOVector
*qiov
, int nb_sectors
,
1985 BlockDriverCompletionFunc
*cb
, void *opaque
)
1987 BlockDriver
*drv
= bs
->drv
;
1988 BlockDriverAIOCB
*ret
;
1994 if (bdrv_check_request(bs
, sector_num
, nb_sectors
))
1997 if (bs
->dirty_bitmap
) {
1998 set_dirty_bitmap(bs
, sector_num
, nb_sectors
, 1);
2001 ret
= drv
->bdrv_aio_writev(bs
, sector_num
, qiov
, nb_sectors
,
2005 /* Update stats even though technically transfer has not happened. */
2006 bs
->wr_bytes
+= (unsigned) nb_sectors
* BDRV_SECTOR_SIZE
;
2008 if (bs
->wr_highest_sector
< sector_num
+ nb_sectors
- 1) {
2009 bs
->wr_highest_sector
= sector_num
+ nb_sectors
- 1;
2017 typedef struct MultiwriteCB
{
2022 BlockDriverCompletionFunc
*cb
;
2024 QEMUIOVector
*free_qiov
;
2029 static void multiwrite_user_cb(MultiwriteCB
*mcb
)
2033 for (i
= 0; i
< mcb
->num_callbacks
; i
++) {
2034 mcb
->callbacks
[i
].cb(mcb
->callbacks
[i
].opaque
, mcb
->error
);
2035 if (mcb
->callbacks
[i
].free_qiov
) {
2036 qemu_iovec_destroy(mcb
->callbacks
[i
].free_qiov
);
2038 qemu_free(mcb
->callbacks
[i
].free_qiov
);
2039 qemu_vfree(mcb
->callbacks
[i
].free_buf
);
2043 static void multiwrite_cb(void *opaque
, int ret
)
2045 MultiwriteCB
*mcb
= opaque
;
2047 if (ret
< 0 && !mcb
->error
) {
2051 mcb
->num_requests
--;
2052 if (mcb
->num_requests
== 0) {
2053 multiwrite_user_cb(mcb
);
2058 static int multiwrite_req_compare(const void *a
, const void *b
)
2060 const BlockRequest
*req1
= a
, *req2
= b
;
2063 * Note that we can't simply subtract req2->sector from req1->sector
2064 * here as that could overflow the return value.
2066 if (req1
->sector
> req2
->sector
) {
2068 } else if (req1
->sector
< req2
->sector
) {
2076 * Takes a bunch of requests and tries to merge them. Returns the number of
2077 * requests that remain after merging.
2079 static int multiwrite_merge(BlockDriverState
*bs
, BlockRequest
*reqs
,
2080 int num_reqs
, MultiwriteCB
*mcb
)
2084 // Sort requests by start sector
2085 qsort(reqs
, num_reqs
, sizeof(*reqs
), &multiwrite_req_compare
);
2087 // Check if adjacent requests touch the same clusters. If so, combine them,
2088 // filling up gaps with zero sectors.
2090 for (i
= 1; i
< num_reqs
; i
++) {
2092 int64_t oldreq_last
= reqs
[outidx
].sector
+ reqs
[outidx
].nb_sectors
;
2094 // This handles the cases that are valid for all block drivers, namely
2095 // exactly sequential writes and overlapping writes.
2096 if (reqs
[i
].sector
<= oldreq_last
) {
2100 // The block driver may decide that it makes sense to combine requests
2101 // even if there is a gap of some sectors between them. In this case,
2102 // the gap is filled with zeros (therefore only applicable for yet
2103 // unused space in format like qcow2).
2104 if (!merge
&& bs
->drv
->bdrv_merge_requests
) {
2105 merge
= bs
->drv
->bdrv_merge_requests(bs
, &reqs
[outidx
], &reqs
[i
]);
2108 if (reqs
[outidx
].qiov
->niov
+ reqs
[i
].qiov
->niov
+ 1 > IOV_MAX
) {
2114 QEMUIOVector
*qiov
= qemu_mallocz(sizeof(*qiov
));
2115 qemu_iovec_init(qiov
,
2116 reqs
[outidx
].qiov
->niov
+ reqs
[i
].qiov
->niov
+ 1);
2118 // Add the first request to the merged one. If the requests are
2119 // overlapping, drop the last sectors of the first request.
2120 size
= (reqs
[i
].sector
- reqs
[outidx
].sector
) << 9;
2121 qemu_iovec_concat(qiov
, reqs
[outidx
].qiov
, size
);
2123 // We might need to add some zeros between the two requests
2124 if (reqs
[i
].sector
> oldreq_last
) {
2125 size_t zero_bytes
= (reqs
[i
].sector
- oldreq_last
) << 9;
2126 uint8_t *buf
= qemu_blockalign(bs
, zero_bytes
);
2127 memset(buf
, 0, zero_bytes
);
2128 qemu_iovec_add(qiov
, buf
, zero_bytes
);
2129 mcb
->callbacks
[i
].free_buf
= buf
;
2132 // Add the second request
2133 qemu_iovec_concat(qiov
, reqs
[i
].qiov
, reqs
[i
].qiov
->size
);
2135 reqs
[outidx
].nb_sectors
= qiov
->size
>> 9;
2136 reqs
[outidx
].qiov
= qiov
;
2138 mcb
->callbacks
[i
].free_qiov
= reqs
[outidx
].qiov
;
2141 reqs
[outidx
].sector
= reqs
[i
].sector
;
2142 reqs
[outidx
].nb_sectors
= reqs
[i
].nb_sectors
;
2143 reqs
[outidx
].qiov
= reqs
[i
].qiov
;
2151 * Submit multiple AIO write requests at once.
2153 * On success, the function returns 0 and all requests in the reqs array have
2154 * been submitted. In error case this function returns -1, and any of the
2155 * requests may or may not be submitted yet. In particular, this means that the
2156 * callback will be called for some of the requests, for others it won't. The
2157 * caller must check the error field of the BlockRequest to wait for the right
2158 * callbacks (if error != 0, no callback will be called).
2160 * The implementation may modify the contents of the reqs array, e.g. to merge
2161 * requests. However, the fields opaque and error are left unmodified as they
2162 * are used to signal failure for a single request to the caller.
2164 int bdrv_aio_multiwrite(BlockDriverState
*bs
, BlockRequest
*reqs
, int num_reqs
)
2166 BlockDriverAIOCB
*acb
;
2170 if (num_reqs
== 0) {
2174 // Create MultiwriteCB structure
2175 mcb
= qemu_mallocz(sizeof(*mcb
) + num_reqs
* sizeof(*mcb
->callbacks
));
2176 mcb
->num_requests
= 0;
2177 mcb
->num_callbacks
= num_reqs
;
2179 for (i
= 0; i
< num_reqs
; i
++) {
2180 mcb
->callbacks
[i
].cb
= reqs
[i
].cb
;
2181 mcb
->callbacks
[i
].opaque
= reqs
[i
].opaque
;
2184 // Check for mergable requests
2185 num_reqs
= multiwrite_merge(bs
, reqs
, num_reqs
, mcb
);
2188 * Run the aio requests. As soon as one request can't be submitted
2189 * successfully, fail all requests that are not yet submitted (we must
2190 * return failure for all requests anyway)
2192 * num_requests cannot be set to the right value immediately: If
2193 * bdrv_aio_writev fails for some request, num_requests would be too high
2194 * and therefore multiwrite_cb() would never recognize the multiwrite
2195 * request as completed. We also cannot use the loop variable i to set it
2196 * when the first request fails because the callback may already have been
2197 * called for previously submitted requests. Thus, num_requests must be
2198 * incremented for each request that is submitted.
2200 * The problem that callbacks may be called early also means that we need
2201 * to take care that num_requests doesn't become 0 before all requests are
2202 * submitted - multiwrite_cb() would consider the multiwrite request
2203 * completed. A dummy request that is "completed" by a manual call to
2204 * multiwrite_cb() takes care of this.
2206 mcb
->num_requests
= 1;
2208 for (i
= 0; i
< num_reqs
; i
++) {
2209 mcb
->num_requests
++;
2210 acb
= bdrv_aio_writev(bs
, reqs
[i
].sector
, reqs
[i
].qiov
,
2211 reqs
[i
].nb_sectors
, multiwrite_cb
, mcb
);
2214 // We can only fail the whole thing if no request has been
2215 // submitted yet. Otherwise we'll wait for the submitted AIOs to
2216 // complete and report the error in the callback.
2220 multiwrite_cb(mcb
, -EIO
);
2226 /* Complete the dummy request */
2227 multiwrite_cb(mcb
, 0);
2232 for (i
= 0; i
< mcb
->num_callbacks
; i
++) {
2233 reqs
[i
].error
= -EIO
;
2239 BlockDriverAIOCB
*bdrv_aio_flush(BlockDriverState
*bs
,
2240 BlockDriverCompletionFunc
*cb
, void *opaque
)
2242 BlockDriver
*drv
= bs
->drv
;
2244 if (bs
->open_flags
& BDRV_O_NO_FLUSH
) {
2245 return bdrv_aio_noop_em(bs
, cb
, opaque
);
2250 return drv
->bdrv_aio_flush(bs
, cb
, opaque
);
2253 void bdrv_aio_cancel(BlockDriverAIOCB
*acb
)
2255 acb
->pool
->cancel(acb
);
2259 /**************************************************************/
2260 /* async block device emulation */
2262 typedef struct BlockDriverAIOCBSync
{
2263 BlockDriverAIOCB common
;
2266 /* vector translation state */
2270 } BlockDriverAIOCBSync
;
2272 static void bdrv_aio_cancel_em(BlockDriverAIOCB
*blockacb
)
2274 BlockDriverAIOCBSync
*acb
=
2275 container_of(blockacb
, BlockDriverAIOCBSync
, common
);
2276 qemu_bh_delete(acb
->bh
);
2278 qemu_aio_release(acb
);
2281 static AIOPool bdrv_em_aio_pool
= {
2282 .aiocb_size
= sizeof(BlockDriverAIOCBSync
),
2283 .cancel
= bdrv_aio_cancel_em
,
2286 static void bdrv_aio_bh_cb(void *opaque
)
2288 BlockDriverAIOCBSync
*acb
= opaque
;
2291 qemu_iovec_from_buffer(acb
->qiov
, acb
->bounce
, acb
->qiov
->size
);
2292 qemu_vfree(acb
->bounce
);
2293 acb
->common
.cb(acb
->common
.opaque
, acb
->ret
);
2294 qemu_bh_delete(acb
->bh
);
2296 qemu_aio_release(acb
);
2299 static BlockDriverAIOCB
*bdrv_aio_rw_vector(BlockDriverState
*bs
,
2303 BlockDriverCompletionFunc
*cb
,
2308 BlockDriverAIOCBSync
*acb
;
2310 acb
= qemu_aio_get(&bdrv_em_aio_pool
, bs
, cb
, opaque
);
2311 acb
->is_write
= is_write
;
2313 acb
->bounce
= qemu_blockalign(bs
, qiov
->size
);
2316 acb
->bh
= qemu_bh_new(bdrv_aio_bh_cb
, acb
);
2319 qemu_iovec_to_buffer(acb
->qiov
, acb
->bounce
);
2320 acb
->ret
= bdrv_write(bs
, sector_num
, acb
->bounce
, nb_sectors
);
2322 acb
->ret
= bdrv_read(bs
, sector_num
, acb
->bounce
, nb_sectors
);
2325 qemu_bh_schedule(acb
->bh
);
2327 return &acb
->common
;
2330 static BlockDriverAIOCB
*bdrv_aio_readv_em(BlockDriverState
*bs
,
2331 int64_t sector_num
, QEMUIOVector
*qiov
, int nb_sectors
,
2332 BlockDriverCompletionFunc
*cb
, void *opaque
)
2334 return bdrv_aio_rw_vector(bs
, sector_num
, qiov
, nb_sectors
, cb
, opaque
, 0);
2337 static BlockDriverAIOCB
*bdrv_aio_writev_em(BlockDriverState
*bs
,
2338 int64_t sector_num
, QEMUIOVector
*qiov
, int nb_sectors
,
2339 BlockDriverCompletionFunc
*cb
, void *opaque
)
2341 return bdrv_aio_rw_vector(bs
, sector_num
, qiov
, nb_sectors
, cb
, opaque
, 1);
2344 static BlockDriverAIOCB
*bdrv_aio_flush_em(BlockDriverState
*bs
,
2345 BlockDriverCompletionFunc
*cb
, void *opaque
)
2347 BlockDriverAIOCBSync
*acb
;
2349 acb
= qemu_aio_get(&bdrv_em_aio_pool
, bs
, cb
, opaque
);
2350 acb
->is_write
= 1; /* don't bounce in the completion hadler */
2356 acb
->bh
= qemu_bh_new(bdrv_aio_bh_cb
, acb
);
2359 qemu_bh_schedule(acb
->bh
);
2360 return &acb
->common
;
2363 static BlockDriverAIOCB
*bdrv_aio_noop_em(BlockDriverState
*bs
,
2364 BlockDriverCompletionFunc
*cb
, void *opaque
)
2366 BlockDriverAIOCBSync
*acb
;
2368 acb
= qemu_aio_get(&bdrv_em_aio_pool
, bs
, cb
, opaque
);
2369 acb
->is_write
= 1; /* don't bounce in the completion handler */
2375 acb
->bh
= qemu_bh_new(bdrv_aio_bh_cb
, acb
);
2378 qemu_bh_schedule(acb
->bh
);
2379 return &acb
->common
;
2382 /**************************************************************/
2383 /* sync block device emulation */
2385 static void bdrv_rw_em_cb(void *opaque
, int ret
)
2387 *(int *)opaque
= ret
;
2390 #define NOT_DONE 0x7fffffff
2392 static int bdrv_read_em(BlockDriverState
*bs
, int64_t sector_num
,
2393 uint8_t *buf
, int nb_sectors
)
2396 BlockDriverAIOCB
*acb
;
2400 async_context_push();
2402 async_ret
= NOT_DONE
;
2403 iov
.iov_base
= (void *)buf
;
2404 iov
.iov_len
= nb_sectors
* BDRV_SECTOR_SIZE
;
2405 qemu_iovec_init_external(&qiov
, &iov
, 1);
2406 acb
= bdrv_aio_readv(bs
, sector_num
, &qiov
, nb_sectors
,
2407 bdrv_rw_em_cb
, &async_ret
);
2413 while (async_ret
== NOT_DONE
) {
2419 async_context_pop();
2423 static int bdrv_write_em(BlockDriverState
*bs
, int64_t sector_num
,
2424 const uint8_t *buf
, int nb_sectors
)
2427 BlockDriverAIOCB
*acb
;
2431 async_context_push();
2433 async_ret
= NOT_DONE
;
2434 iov
.iov_base
= (void *)buf
;
2435 iov
.iov_len
= nb_sectors
* BDRV_SECTOR_SIZE
;
2436 qemu_iovec_init_external(&qiov
, &iov
, 1);
2437 acb
= bdrv_aio_writev(bs
, sector_num
, &qiov
, nb_sectors
,
2438 bdrv_rw_em_cb
, &async_ret
);
2443 while (async_ret
== NOT_DONE
) {
2448 async_context_pop();
2452 void bdrv_init(void)
2454 module_call_init(MODULE_INIT_BLOCK
);
2457 void bdrv_init_with_whitelist(void)
2459 use_bdrv_whitelist
= 1;
2463 void *qemu_aio_get(AIOPool
*pool
, BlockDriverState
*bs
,
2464 BlockDriverCompletionFunc
*cb
, void *opaque
)
2466 BlockDriverAIOCB
*acb
;
2468 if (pool
->free_aiocb
) {
2469 acb
= pool
->free_aiocb
;
2470 pool
->free_aiocb
= acb
->next
;
2472 acb
= qemu_mallocz(pool
->aiocb_size
);
2477 acb
->opaque
= opaque
;
2481 void qemu_aio_release(void *p
)
2483 BlockDriverAIOCB
*acb
= (BlockDriverAIOCB
*)p
;
2484 AIOPool
*pool
= acb
->pool
;
2485 acb
->next
= pool
->free_aiocb
;
2486 pool
->free_aiocb
= acb
;
2489 /**************************************************************/
2490 /* removable device support */
2493 * Return TRUE if the media is present
2495 int bdrv_is_inserted(BlockDriverState
*bs
)
2497 BlockDriver
*drv
= bs
->drv
;
2501 if (!drv
->bdrv_is_inserted
)
2503 ret
= drv
->bdrv_is_inserted(bs
);
2508 * Return TRUE if the media changed since the last call to this
2509 * function. It is currently only used for floppy disks
2511 int bdrv_media_changed(BlockDriverState
*bs
)
2513 BlockDriver
*drv
= bs
->drv
;
2516 if (!drv
|| !drv
->bdrv_media_changed
)
2519 ret
= drv
->bdrv_media_changed(bs
);
2520 if (ret
== -ENOTSUP
)
2521 ret
= bs
->media_changed
;
2522 bs
->media_changed
= 0;
2527 * If eject_flag is TRUE, eject the media. Otherwise, close the tray
2529 int bdrv_eject(BlockDriverState
*bs
, int eject_flag
)
2531 BlockDriver
*drv
= bs
->drv
;
2538 if (!drv
|| !drv
->bdrv_eject
) {
2541 ret
= drv
->bdrv_eject(bs
, eject_flag
);
2543 if (ret
== -ENOTSUP
) {
2552 int bdrv_is_locked(BlockDriverState
*bs
)
2558 * Lock or unlock the media (if it is locked, the user won't be able
2559 * to eject it manually).
2561 void bdrv_set_locked(BlockDriverState
*bs
, int locked
)
2563 BlockDriver
*drv
= bs
->drv
;
2565 bs
->locked
= locked
;
2566 if (drv
&& drv
->bdrv_set_locked
) {
2567 drv
->bdrv_set_locked(bs
, locked
);
2571 /* needed for generic scsi interface */
2573 int bdrv_ioctl(BlockDriverState
*bs
, unsigned long int req
, void *buf
)
2575 BlockDriver
*drv
= bs
->drv
;
2577 if (drv
&& drv
->bdrv_ioctl
)
2578 return drv
->bdrv_ioctl(bs
, req
, buf
);
2582 BlockDriverAIOCB
*bdrv_aio_ioctl(BlockDriverState
*bs
,
2583 unsigned long int req
, void *buf
,
2584 BlockDriverCompletionFunc
*cb
, void *opaque
)
2586 BlockDriver
*drv
= bs
->drv
;
2588 if (drv
&& drv
->bdrv_aio_ioctl
)
2589 return drv
->bdrv_aio_ioctl(bs
, req
, buf
, cb
, opaque
);
2595 void *qemu_blockalign(BlockDriverState
*bs
, size_t size
)
2597 return qemu_memalign((bs
&& bs
->buffer_alignment
) ? bs
->buffer_alignment
: 512, size
);
2600 void bdrv_set_dirty_tracking(BlockDriverState
*bs
, int enable
)
2602 int64_t bitmap_size
;
2604 bs
->dirty_count
= 0;
2606 if (!bs
->dirty_bitmap
) {
2607 bitmap_size
= (bdrv_getlength(bs
) >> BDRV_SECTOR_BITS
) +
2608 BDRV_SECTORS_PER_DIRTY_CHUNK
* 8 - 1;
2609 bitmap_size
/= BDRV_SECTORS_PER_DIRTY_CHUNK
* 8;
2611 bs
->dirty_bitmap
= qemu_mallocz(bitmap_size
);
2614 if (bs
->dirty_bitmap
) {
2615 qemu_free(bs
->dirty_bitmap
);
2616 bs
->dirty_bitmap
= NULL
;
2621 int bdrv_get_dirty(BlockDriverState
*bs
, int64_t sector
)
2623 int64_t chunk
= sector
/ (int64_t)BDRV_SECTORS_PER_DIRTY_CHUNK
;
2625 if (bs
->dirty_bitmap
&&
2626 (sector
<< BDRV_SECTOR_BITS
) < bdrv_getlength(bs
)) {
2627 return bs
->dirty_bitmap
[chunk
/ (sizeof(unsigned long) * 8)] &
2628 (1 << (chunk
% (sizeof(unsigned long) * 8)));
2634 void bdrv_reset_dirty(BlockDriverState
*bs
, int64_t cur_sector
,
2637 set_dirty_bitmap(bs
, cur_sector
, nr_sectors
, 0);
2640 int64_t bdrv_get_dirty_count(BlockDriverState
*bs
)
2642 return bs
->dirty_count
;