mirror of https://gitee.com/openkylin/qemu.git
271 lines
8.2 KiB
C
271 lines
8.2 KiB
C
/* BlockDriver implementation for "raw"
|
|
*
|
|
* Copyright (C) 2010, 2013, Red Hat, Inc.
|
|
* Copyright (C) 2010, Blue Swirl <blauwirbel@gmail.com>
|
|
* Copyright (C) 2009, Anthony Liguori <aliguori@us.ibm.com>
|
|
*
|
|
* Author:
|
|
* Laszlo Ersek <lersek@redhat.com>
|
|
*
|
|
* Permission is hereby granted, free of charge, to any person obtaining a copy
|
|
* of this software and associated documentation files (the "Software"), to
|
|
* deal in the Software without restriction, including without limitation the
|
|
* rights to use, copy, modify, merge, publish, distribute, sublicense, and/or
|
|
* sell copies of the Software, and to permit persons to whom the Software is
|
|
* furnished to do so, subject to the following conditions:
|
|
*
|
|
* The above copyright notice and this permission notice shall be included in
|
|
* all copies or substantial portions of the Software.
|
|
*
|
|
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
|
|
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
|
|
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
|
|
* AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
|
|
* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
|
|
* FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
|
|
* IN THE SOFTWARE.
|
|
*/
|
|
|
|
#include "block/block_int.h"
|
|
#include "qemu/option.h"
|
|
|
|
static QemuOptsList raw_create_opts = {
|
|
.name = "raw-create-opts",
|
|
.head = QTAILQ_HEAD_INITIALIZER(raw_create_opts.head),
|
|
.desc = {
|
|
{
|
|
.name = BLOCK_OPT_SIZE,
|
|
.type = QEMU_OPT_SIZE,
|
|
.help = "Virtual disk size"
|
|
},
|
|
{ /* end of list */ }
|
|
}
|
|
};
|
|
|
|
static int raw_reopen_prepare(BDRVReopenState *reopen_state,
|
|
BlockReopenQueue *queue, Error **errp)
|
|
{
|
|
return 0;
|
|
}
|
|
|
|
static int coroutine_fn raw_co_readv(BlockDriverState *bs, int64_t sector_num,
|
|
int nb_sectors, QEMUIOVector *qiov)
|
|
{
|
|
BLKDBG_EVENT(bs->file, BLKDBG_READ_AIO);
|
|
return bdrv_co_readv(bs->file, sector_num, nb_sectors, qiov);
|
|
}
|
|
|
|
static int coroutine_fn raw_co_writev(BlockDriverState *bs, int64_t sector_num,
|
|
int nb_sectors, QEMUIOVector *qiov)
|
|
{
|
|
void *buf = NULL;
|
|
BlockDriver *drv;
|
|
QEMUIOVector local_qiov;
|
|
int ret;
|
|
|
|
if (bs->probed && sector_num == 0) {
|
|
/* As long as these conditions are true, we can't get partial writes to
|
|
* the probe buffer and can just directly check the request. */
|
|
QEMU_BUILD_BUG_ON(BLOCK_PROBE_BUF_SIZE != 512);
|
|
QEMU_BUILD_BUG_ON(BDRV_SECTOR_SIZE != 512);
|
|
|
|
if (nb_sectors == 0) {
|
|
/* qemu_iovec_to_buf() would fail, but we want to return success
|
|
* instead of -EINVAL in this case. */
|
|
return 0;
|
|
}
|
|
|
|
buf = qemu_try_blockalign(bs->file, 512);
|
|
if (!buf) {
|
|
ret = -ENOMEM;
|
|
goto fail;
|
|
}
|
|
|
|
ret = qemu_iovec_to_buf(qiov, 0, buf, 512);
|
|
if (ret != 512) {
|
|
ret = -EINVAL;
|
|
goto fail;
|
|
}
|
|
|
|
drv = bdrv_probe_all(buf, 512, NULL);
|
|
if (drv != bs->drv) {
|
|
ret = -EPERM;
|
|
goto fail;
|
|
}
|
|
|
|
/* Use the checked buffer, a malicious guest might be overwriting its
|
|
* original buffer in the background. */
|
|
qemu_iovec_init(&local_qiov, qiov->niov + 1);
|
|
qemu_iovec_add(&local_qiov, buf, 512);
|
|
qemu_iovec_concat(&local_qiov, qiov, 512, qiov->size - 512);
|
|
qiov = &local_qiov;
|
|
}
|
|
|
|
BLKDBG_EVENT(bs->file, BLKDBG_WRITE_AIO);
|
|
ret = bdrv_co_writev(bs->file, sector_num, nb_sectors, qiov);
|
|
|
|
fail:
|
|
if (qiov == &local_qiov) {
|
|
qemu_iovec_destroy(&local_qiov);
|
|
}
|
|
qemu_vfree(buf);
|
|
return ret;
|
|
}
|
|
|
|
static int64_t coroutine_fn raw_co_get_block_status(BlockDriverState *bs,
|
|
int64_t sector_num,
|
|
int nb_sectors, int *pnum)
|
|
{
|
|
*pnum = nb_sectors;
|
|
return BDRV_BLOCK_RAW | BDRV_BLOCK_OFFSET_VALID | BDRV_BLOCK_DATA |
|
|
(sector_num << BDRV_SECTOR_BITS);
|
|
}
|
|
|
|
static int coroutine_fn raw_co_write_zeroes(BlockDriverState *bs,
|
|
int64_t sector_num, int nb_sectors,
|
|
BdrvRequestFlags flags)
|
|
{
|
|
return bdrv_co_write_zeroes(bs->file, sector_num, nb_sectors, flags);
|
|
}
|
|
|
|
static int coroutine_fn raw_co_discard(BlockDriverState *bs,
|
|
int64_t sector_num, int nb_sectors)
|
|
{
|
|
return bdrv_co_discard(bs->file, sector_num, nb_sectors);
|
|
}
|
|
|
|
static int64_t raw_getlength(BlockDriverState *bs)
|
|
{
|
|
return bdrv_getlength(bs->file);
|
|
}
|
|
|
|
static int raw_get_info(BlockDriverState *bs, BlockDriverInfo *bdi)
|
|
{
|
|
return bdrv_get_info(bs->file, bdi);
|
|
}
|
|
|
|
static void raw_refresh_limits(BlockDriverState *bs, Error **errp)
|
|
{
|
|
bs->bl = bs->file->bl;
|
|
}
|
|
|
|
static int raw_truncate(BlockDriverState *bs, int64_t offset)
|
|
{
|
|
return bdrv_truncate(bs->file, offset);
|
|
}
|
|
|
|
static int raw_is_inserted(BlockDriverState *bs)
|
|
{
|
|
return bdrv_is_inserted(bs->file);
|
|
}
|
|
|
|
static int raw_media_changed(BlockDriverState *bs)
|
|
{
|
|
return bdrv_media_changed(bs->file);
|
|
}
|
|
|
|
static void raw_eject(BlockDriverState *bs, bool eject_flag)
|
|
{
|
|
bdrv_eject(bs->file, eject_flag);
|
|
}
|
|
|
|
static void raw_lock_medium(BlockDriverState *bs, bool locked)
|
|
{
|
|
bdrv_lock_medium(bs->file, locked);
|
|
}
|
|
|
|
static int raw_ioctl(BlockDriverState *bs, unsigned long int req, void *buf)
|
|
{
|
|
return bdrv_ioctl(bs->file, req, buf);
|
|
}
|
|
|
|
static BlockAIOCB *raw_aio_ioctl(BlockDriverState *bs,
|
|
unsigned long int req, void *buf,
|
|
BlockCompletionFunc *cb,
|
|
void *opaque)
|
|
{
|
|
return bdrv_aio_ioctl(bs->file, req, buf, cb, opaque);
|
|
}
|
|
|
|
static int raw_has_zero_init(BlockDriverState *bs)
|
|
{
|
|
return bdrv_has_zero_init(bs->file);
|
|
}
|
|
|
|
static int raw_create(const char *filename, QemuOpts *opts, Error **errp)
|
|
{
|
|
Error *local_err = NULL;
|
|
int ret;
|
|
|
|
ret = bdrv_create_file(filename, opts, &local_err);
|
|
if (local_err) {
|
|
error_propagate(errp, local_err);
|
|
}
|
|
return ret;
|
|
}
|
|
|
|
static int raw_open(BlockDriverState *bs, QDict *options, int flags,
|
|
Error **errp)
|
|
{
|
|
bs->sg = bs->file->sg;
|
|
|
|
if (bs->probed && !bdrv_is_read_only(bs)) {
|
|
fprintf(stderr,
|
|
"WARNING: Image format was not specified for '%s' and probing "
|
|
"guessed raw.\n"
|
|
" Automatically detecting the format is dangerous for "
|
|
"raw images, write operations on block 0 will be restricted.\n"
|
|
" Specify the 'raw' format explicitly to remove the "
|
|
"restrictions.\n",
|
|
bs->file->filename);
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
static void raw_close(BlockDriverState *bs)
|
|
{
|
|
}
|
|
|
|
static int raw_probe(const uint8_t *buf, int buf_size, const char *filename)
|
|
{
|
|
/* smallest possible positive score so that raw is used if and only if no
|
|
* other block driver works
|
|
*/
|
|
return 1;
|
|
}
|
|
|
|
BlockDriver bdrv_raw = {
|
|
.format_name = "raw",
|
|
.bdrv_probe = &raw_probe,
|
|
.bdrv_reopen_prepare = &raw_reopen_prepare,
|
|
.bdrv_open = &raw_open,
|
|
.bdrv_close = &raw_close,
|
|
.bdrv_create = &raw_create,
|
|
.bdrv_co_readv = &raw_co_readv,
|
|
.bdrv_co_writev = &raw_co_writev,
|
|
.bdrv_co_write_zeroes = &raw_co_write_zeroes,
|
|
.bdrv_co_discard = &raw_co_discard,
|
|
.bdrv_co_get_block_status = &raw_co_get_block_status,
|
|
.bdrv_truncate = &raw_truncate,
|
|
.bdrv_getlength = &raw_getlength,
|
|
.has_variable_length = true,
|
|
.bdrv_get_info = &raw_get_info,
|
|
.bdrv_refresh_limits = &raw_refresh_limits,
|
|
.bdrv_is_inserted = &raw_is_inserted,
|
|
.bdrv_media_changed = &raw_media_changed,
|
|
.bdrv_eject = &raw_eject,
|
|
.bdrv_lock_medium = &raw_lock_medium,
|
|
.bdrv_ioctl = &raw_ioctl,
|
|
.bdrv_aio_ioctl = &raw_aio_ioctl,
|
|
.create_opts = &raw_create_opts,
|
|
.bdrv_has_zero_init = &raw_has_zero_init
|
|
};
|
|
|
|
static void bdrv_raw_init(void)
|
|
{
|
|
bdrv_register(&bdrv_raw);
|
|
}
|
|
|
|
block_init(bdrv_raw_init);
|