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/*
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* QEMU System Emulator block driver
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*
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* Copyright (c) 2003 Fabrice Bellard
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*
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* Permission is hereby granted, free of charge, to any person obtaining a copy
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* of this software and associated documentation files (the "Software"), to deal
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* in the Software without restriction, including without limitation the rights
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* to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
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* copies of the Software, and to permit persons to whom the Software is
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* furnished to do so, subject to the following conditions:
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*
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* The above copyright notice and this permission notice shall be included in
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* all copies or substantial portions of the Software.
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*
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* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
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* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
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* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
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* THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
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* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
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* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
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* THE SOFTWARE.
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*/
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#include "vl.h" |
25 |
#include "block_int.h" |
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static BlockDriverState *bdrv_first;
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static BlockDriver *first_drv;
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|
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void bdrv_register(BlockDriver *bdrv)
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{ |
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bdrv->next = first_drv; |
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first_drv = bdrv; |
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} |
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|
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/* create a new block device (by default it is empty) */
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BlockDriverState *bdrv_new(const char *device_name) |
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{ |
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BlockDriverState **pbs, *bs; |
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|
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bs = qemu_mallocz(sizeof(BlockDriverState));
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if(!bs)
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return NULL; |
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pstrcpy(bs->device_name, sizeof(bs->device_name), device_name);
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if (device_name[0] != '\0') { |
46 |
/* insert at the end */
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pbs = &bdrv_first; |
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while (*pbs != NULL) |
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pbs = &(*pbs)->next; |
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*pbs = bs; |
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} |
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return bs;
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} |
54 |
|
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BlockDriver *bdrv_find_format(const char *format_name) |
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{ |
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BlockDriver *drv1; |
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for(drv1 = first_drv; drv1 != NULL; drv1 = drv1->next) { |
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if (!strcmp(drv1->format_name, format_name))
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return drv1;
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} |
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return NULL; |
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} |
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|
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int bdrv_create(BlockDriver *drv,
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const char *filename, int64_t size_in_sectors, |
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const char *backing_file, int flags) |
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{ |
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if (!drv->bdrv_create)
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return -ENOTSUP;
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return drv->bdrv_create(filename, size_in_sectors, backing_file, flags);
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} |
73 |
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#ifdef _WIN32
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static void get_tmp_filename(char *filename, int size) |
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{ |
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/* XXX: find a better function */
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tmpnam(filename); |
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} |
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#else
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static void get_tmp_filename(char *filename, int size) |
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{ |
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int fd;
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/* XXX: race condition possible */
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pstrcpy(filename, size, "/tmp/vl.XXXXXX");
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fd = mkstemp(filename); |
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close(fd); |
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} |
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#endif
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static BlockDriver *find_image_format(const char *filename) |
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{ |
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int fd, ret, score, score_max;
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BlockDriver *drv1, *drv; |
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uint8_t buf[1024];
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fd = open(filename, O_RDONLY | O_BINARY | O_LARGEFILE); |
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if (fd < 0) |
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return NULL; |
100 |
ret = read(fd, buf, sizeof(buf));
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if (ret < 0) { |
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close(fd); |
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return NULL; |
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} |
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close(fd); |
106 |
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drv = NULL;
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score_max = 0;
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for(drv1 = first_drv; drv1 != NULL; drv1 = drv1->next) { |
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score = drv1->bdrv_probe(buf, ret, filename); |
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if (score > score_max) {
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score_max = score; |
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drv = drv1; |
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} |
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} |
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return drv;
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} |
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int bdrv_open(BlockDriverState *bs, const char *filename, int snapshot) |
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{ |
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return bdrv_open2(bs, filename, snapshot, NULL); |
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} |
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int bdrv_open2(BlockDriverState *bs, const char *filename, int snapshot, |
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BlockDriver *drv) |
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{ |
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int ret;
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char tmp_filename[1024]; |
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|
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bs->read_only = 0;
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bs->is_temporary = 0;
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bs->encrypted = 0;
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if (snapshot) {
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BlockDriverState *bs1; |
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int64_t total_size; |
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/* if snapshot, we create a temporary backing file and open it
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instead of opening 'filename' directly */
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/* if there is a backing file, use it */
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bs1 = bdrv_new("");
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if (!bs1) {
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return -1; |
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} |
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if (bdrv_open(bs1, filename, 0) < 0) { |
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bdrv_delete(bs1); |
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return -1; |
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} |
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total_size = bs1->total_sectors; |
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bdrv_delete(bs1); |
152 |
|
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get_tmp_filename(tmp_filename, sizeof(tmp_filename));
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/* XXX: use cow for linux as it is more efficient ? */
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if (bdrv_create(&bdrv_qcow, tmp_filename,
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total_size, filename, 0) < 0) { |
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return -1; |
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} |
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filename = tmp_filename; |
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bs->is_temporary = 1;
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} |
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pstrcpy(bs->filename, sizeof(bs->filename), filename);
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if (!drv) {
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drv = find_image_format(filename); |
166 |
if (!drv)
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return -1; |
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} |
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bs->drv = drv; |
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bs->opaque = qemu_mallocz(drv->instance_size); |
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if (bs->opaque == NULL && drv->instance_size > 0) |
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return -1; |
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ret = drv->bdrv_open(bs, filename); |
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if (ret < 0) { |
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qemu_free(bs->opaque); |
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return -1; |
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} |
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#ifndef _WIN32
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if (bs->is_temporary) {
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unlink(filename); |
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} |
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#endif
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if (bs->backing_file[0] != '\0' && drv->bdrv_is_allocated) { |
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/* if there is a backing file, use it */
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bs->backing_hd = bdrv_new("");
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if (!bs->backing_hd) {
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fail:
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bdrv_close(bs); |
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return -1; |
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} |
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if (bdrv_open(bs->backing_hd, bs->backing_file, 0) < 0) |
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goto fail;
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} |
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bs->inserted = 1;
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/* call the change callback */
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if (bs->change_cb)
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bs->change_cb(bs->change_opaque); |
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return 0; |
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} |
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void bdrv_close(BlockDriverState *bs)
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{ |
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if (bs->inserted) {
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if (bs->backing_hd)
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bdrv_delete(bs->backing_hd); |
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bs->drv->bdrv_close(bs); |
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qemu_free(bs->opaque); |
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#ifdef _WIN32
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if (bs->is_temporary) {
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unlink(bs->filename); |
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} |
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#endif
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bs->opaque = NULL;
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bs->drv = NULL;
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bs->inserted = 0;
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/* call the change callback */
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if (bs->change_cb)
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bs->change_cb(bs->change_opaque); |
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} |
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} |
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void bdrv_delete(BlockDriverState *bs)
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{ |
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/* XXX: remove the driver list */
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bdrv_close(bs); |
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qemu_free(bs); |
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} |
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/* commit COW file into the raw image */
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int bdrv_commit(BlockDriverState *bs)
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{ |
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int64_t i; |
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int n, j;
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unsigned char sector[512]; |
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if (!bs->inserted)
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return -ENOENT;
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if (bs->read_only) {
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return -EACCES;
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} |
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if (!bs->backing_hd) {
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return -ENOTSUP;
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} |
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for (i = 0; i < bs->total_sectors;) { |
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if (bs->drv->bdrv_is_allocated(bs, i, 65536, &n)) { |
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for(j = 0; j < n; j++) { |
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if (bdrv_read(bs, i, sector, 1) != 0) { |
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return -EIO;
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} |
258 |
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if (bdrv_write(bs->backing_hd, i, sector, 1) != 0) { |
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return -EIO;
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} |
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i++; |
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} |
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} else {
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i += n; |
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} |
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} |
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return 0; |
269 |
} |
270 |
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/* return -1 if error */
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int bdrv_read(BlockDriverState *bs, int64_t sector_num,
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uint8_t *buf, int nb_sectors)
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{ |
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int ret, n;
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BlockDriver *drv = bs->drv; |
277 |
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if (!bs->inserted)
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return -1; |
280 |
|
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while (nb_sectors > 0) { |
282 |
if (sector_num == 0 && bs->boot_sector_enabled) { |
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memcpy(buf, bs->boot_sector_data, 512);
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n = 1;
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} else if (bs->backing_hd) { |
286 |
if (drv->bdrv_is_allocated(bs, sector_num, nb_sectors, &n)) {
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ret = drv->bdrv_read(bs, sector_num, buf, n); |
288 |
if (ret < 0) |
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return -1; |
290 |
} else {
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/* read from the base image */
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ret = bdrv_read(bs->backing_hd, sector_num, buf, n); |
293 |
if (ret < 0) |
294 |
return -1; |
295 |
} |
296 |
} else {
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ret = drv->bdrv_read(bs, sector_num, buf, nb_sectors); |
298 |
if (ret < 0) |
299 |
return -1; |
300 |
/* no need to loop */
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break;
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302 |
} |
303 |
nb_sectors -= n; |
304 |
sector_num += n; |
305 |
buf += n * 512;
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} |
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return 0; |
308 |
} |
309 |
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/* return -1 if error */
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int bdrv_write(BlockDriverState *bs, int64_t sector_num,
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const uint8_t *buf, int nb_sectors) |
313 |
{ |
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if (!bs->inserted)
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return -1; |
316 |
if (bs->read_only)
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return -1; |
318 |
return bs->drv->bdrv_write(bs, sector_num, buf, nb_sectors);
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} |
320 |
|
321 |
void bdrv_get_geometry(BlockDriverState *bs, int64_t *nb_sectors_ptr)
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{ |
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*nb_sectors_ptr = bs->total_sectors; |
324 |
} |
325 |
|
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/* force a given boot sector. */
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void bdrv_set_boot_sector(BlockDriverState *bs, const uint8_t *data, int size) |
328 |
{ |
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bs->boot_sector_enabled = 1;
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if (size > 512) |
331 |
size = 512;
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memcpy(bs->boot_sector_data, data, size); |
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memset(bs->boot_sector_data + size, 0, 512 - size); |
334 |
} |
335 |
|
336 |
void bdrv_set_geometry_hint(BlockDriverState *bs,
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int cyls, int heads, int secs) |
338 |
{ |
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bs->cyls = cyls; |
340 |
bs->heads = heads; |
341 |
bs->secs = secs; |
342 |
} |
343 |
|
344 |
void bdrv_set_type_hint(BlockDriverState *bs, int type) |
345 |
{ |
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bs->type = type; |
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bs->removable = ((type == BDRV_TYPE_CDROM || |
348 |
type == BDRV_TYPE_FLOPPY)); |
349 |
} |
350 |
|
351 |
void bdrv_set_translation_hint(BlockDriverState *bs, int translation) |
352 |
{ |
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bs->translation = translation; |
354 |
} |
355 |
|
356 |
void bdrv_get_geometry_hint(BlockDriverState *bs,
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357 |
int *pcyls, int *pheads, int *psecs) |
358 |
{ |
359 |
*pcyls = bs->cyls; |
360 |
*pheads = bs->heads; |
361 |
*psecs = bs->secs; |
362 |
} |
363 |
|
364 |
int bdrv_get_type_hint(BlockDriverState *bs)
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365 |
{ |
366 |
return bs->type;
|
367 |
} |
368 |
|
369 |
int bdrv_get_translation_hint(BlockDriverState *bs)
|
370 |
{ |
371 |
return bs->translation;
|
372 |
} |
373 |
|
374 |
int bdrv_is_removable(BlockDriverState *bs)
|
375 |
{ |
376 |
return bs->removable;
|
377 |
} |
378 |
|
379 |
int bdrv_is_read_only(BlockDriverState *bs)
|
380 |
{ |
381 |
return bs->read_only;
|
382 |
} |
383 |
|
384 |
int bdrv_is_inserted(BlockDriverState *bs)
|
385 |
{ |
386 |
return bs->inserted;
|
387 |
} |
388 |
|
389 |
int bdrv_is_locked(BlockDriverState *bs)
|
390 |
{ |
391 |
return bs->locked;
|
392 |
} |
393 |
|
394 |
void bdrv_set_locked(BlockDriverState *bs, int locked) |
395 |
{ |
396 |
bs->locked = locked; |
397 |
} |
398 |
|
399 |
void bdrv_set_change_cb(BlockDriverState *bs,
|
400 |
void (*change_cb)(void *opaque), void *opaque) |
401 |
{ |
402 |
bs->change_cb = change_cb; |
403 |
bs->change_opaque = opaque; |
404 |
} |
405 |
|
406 |
int bdrv_is_encrypted(BlockDriverState *bs)
|
407 |
{ |
408 |
if (bs->backing_hd && bs->backing_hd->encrypted)
|
409 |
return 1; |
410 |
return bs->encrypted;
|
411 |
} |
412 |
|
413 |
int bdrv_set_key(BlockDriverState *bs, const char *key) |
414 |
{ |
415 |
int ret;
|
416 |
if (bs->backing_hd && bs->backing_hd->encrypted) {
|
417 |
ret = bdrv_set_key(bs->backing_hd, key); |
418 |
if (ret < 0) |
419 |
return ret;
|
420 |
if (!bs->encrypted)
|
421 |
return 0; |
422 |
} |
423 |
if (!bs->encrypted || !bs->drv || !bs->drv->bdrv_set_key)
|
424 |
return -1; |
425 |
return bs->drv->bdrv_set_key(bs, key);
|
426 |
} |
427 |
|
428 |
void bdrv_get_format(BlockDriverState *bs, char *buf, int buf_size) |
429 |
{ |
430 |
if (!bs->inserted || !bs->drv) {
|
431 |
buf[0] = '\0'; |
432 |
} else {
|
433 |
pstrcpy(buf, buf_size, bs->drv->format_name); |
434 |
} |
435 |
} |
436 |
|
437 |
void bdrv_iterate_format(void (*it)(void *opaque, const char *name), |
438 |
void *opaque)
|
439 |
{ |
440 |
BlockDriver *drv; |
441 |
|
442 |
for (drv = first_drv; drv != NULL; drv = drv->next) { |
443 |
it(opaque, drv->format_name); |
444 |
} |
445 |
} |
446 |
|
447 |
BlockDriverState *bdrv_find(const char *name) |
448 |
{ |
449 |
BlockDriverState *bs; |
450 |
|
451 |
for (bs = bdrv_first; bs != NULL; bs = bs->next) { |
452 |
if (!strcmp(name, bs->device_name))
|
453 |
return bs;
|
454 |
} |
455 |
return NULL; |
456 |
} |
457 |
|
458 |
void bdrv_iterate(void (*it)(void *opaque, const char *name), void *opaque) |
459 |
{ |
460 |
BlockDriverState *bs; |
461 |
|
462 |
for (bs = bdrv_first; bs != NULL; bs = bs->next) { |
463 |
it(opaque, bs->device_name); |
464 |
} |
465 |
} |
466 |
|
467 |
const char *bdrv_get_device_name(BlockDriverState *bs) |
468 |
{ |
469 |
return bs->device_name;
|
470 |
} |
471 |
|
472 |
void bdrv_info(void) |
473 |
{ |
474 |
BlockDriverState *bs; |
475 |
|
476 |
for (bs = bdrv_first; bs != NULL; bs = bs->next) { |
477 |
term_printf("%s:", bs->device_name);
|
478 |
term_printf(" type=");
|
479 |
switch(bs->type) {
|
480 |
case BDRV_TYPE_HD:
|
481 |
term_printf("hd");
|
482 |
break;
|
483 |
case BDRV_TYPE_CDROM:
|
484 |
term_printf("cdrom");
|
485 |
break;
|
486 |
case BDRV_TYPE_FLOPPY:
|
487 |
term_printf("floppy");
|
488 |
break;
|
489 |
} |
490 |
term_printf(" removable=%d", bs->removable);
|
491 |
if (bs->removable) {
|
492 |
term_printf(" locked=%d", bs->locked);
|
493 |
} |
494 |
if (bs->inserted) {
|
495 |
term_printf(" file=%s", bs->filename);
|
496 |
if (bs->backing_file[0] != '\0') |
497 |
term_printf(" backing_file=%s", bs->backing_file);
|
498 |
term_printf(" ro=%d", bs->read_only);
|
499 |
term_printf(" drv=%s", bs->drv->format_name);
|
500 |
if (bs->encrypted)
|
501 |
term_printf(" encrypted");
|
502 |
} else {
|
503 |
term_printf(" [not inserted]");
|
504 |
} |
505 |
term_printf("\n");
|
506 |
} |
507 |
} |
508 |
|
509 |
|
510 |
/**************************************************************/
|
511 |
/* RAW block driver */
|
512 |
|
513 |
typedef struct BDRVRawState { |
514 |
int fd;
|
515 |
} BDRVRawState; |
516 |
|
517 |
static int raw_probe(const uint8_t *buf, int buf_size, const char *filename) |
518 |
{ |
519 |
return 1; /* maybe */ |
520 |
} |
521 |
|
522 |
static int raw_open(BlockDriverState *bs, const char *filename) |
523 |
{ |
524 |
BDRVRawState *s = bs->opaque; |
525 |
int fd;
|
526 |
int64_t size; |
527 |
|
528 |
fd = open(filename, O_RDWR | O_BINARY | O_LARGEFILE); |
529 |
if (fd < 0) { |
530 |
fd = open(filename, O_RDONLY | O_BINARY | O_LARGEFILE); |
531 |
if (fd < 0) |
532 |
return -1; |
533 |
bs->read_only = 1;
|
534 |
} |
535 |
size = lseek(fd, 0, SEEK_END);
|
536 |
bs->total_sectors = size / 512;
|
537 |
s->fd = fd; |
538 |
return 0; |
539 |
} |
540 |
|
541 |
static int raw_read(BlockDriverState *bs, int64_t sector_num, |
542 |
uint8_t *buf, int nb_sectors)
|
543 |
{ |
544 |
BDRVRawState *s = bs->opaque; |
545 |
int ret;
|
546 |
|
547 |
lseek(s->fd, sector_num * 512, SEEK_SET);
|
548 |
ret = read(s->fd, buf, nb_sectors * 512);
|
549 |
if (ret != nb_sectors * 512) |
550 |
return -1; |
551 |
return 0; |
552 |
} |
553 |
|
554 |
static int raw_write(BlockDriverState *bs, int64_t sector_num, |
555 |
const uint8_t *buf, int nb_sectors) |
556 |
{ |
557 |
BDRVRawState *s = bs->opaque; |
558 |
int ret;
|
559 |
|
560 |
lseek(s->fd, sector_num * 512, SEEK_SET);
|
561 |
ret = write(s->fd, buf, nb_sectors * 512);
|
562 |
if (ret != nb_sectors * 512) |
563 |
return -1; |
564 |
return 0; |
565 |
} |
566 |
|
567 |
static void raw_close(BlockDriverState *bs) |
568 |
{ |
569 |
BDRVRawState *s = bs->opaque; |
570 |
close(s->fd); |
571 |
} |
572 |
|
573 |
static int raw_create(const char *filename, int64_t total_size, |
574 |
const char *backing_file, int flags) |
575 |
{ |
576 |
int fd;
|
577 |
|
578 |
if (flags || backing_file)
|
579 |
return -ENOTSUP;
|
580 |
|
581 |
fd = open(filename, O_WRONLY | O_CREAT | O_TRUNC | O_BINARY | O_LARGEFILE, |
582 |
0644);
|
583 |
if (fd < 0) |
584 |
return -EIO;
|
585 |
ftruncate(fd, total_size * 512);
|
586 |
close(fd); |
587 |
return 0; |
588 |
} |
589 |
|
590 |
BlockDriver bdrv_raw = { |
591 |
"raw",
|
592 |
sizeof(BDRVRawState),
|
593 |
raw_probe, |
594 |
raw_open, |
595 |
raw_read, |
596 |
raw_write, |
597 |
raw_close, |
598 |
raw_create, |
599 |
}; |
600 |
|
601 |
void bdrv_init(void) |
602 |
{ |
603 |
bdrv_register(&bdrv_raw); |
604 |
#ifndef _WIN32
|
605 |
bdrv_register(&bdrv_cow); |
606 |
#endif
|
607 |
bdrv_register(&bdrv_qcow); |
608 |
bdrv_register(&bdrv_vmdk); |
609 |
bdrv_register(&bdrv_cloop); |
610 |
bdrv_register(&bdrv_dmg); |
611 |
} |