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| 1 |
/*
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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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| 11 |
* 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 "config-host.h" |
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#include "qemu-common.h" |
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#include "trace.h" |
| 27 |
#include "monitor/monitor.h" |
| 28 |
#include "block/block_int.h" |
| 29 |
#include "block/blockjob.h" |
| 30 |
#include "qemu/module.h" |
| 31 |
#include "qapi/qmp/qjson.h" |
| 32 |
#include "sysemu/sysemu.h" |
| 33 |
#include "qemu/notify.h" |
| 34 |
#include "block/coroutine.h" |
| 35 |
#include "block/qapi.h" |
| 36 |
#include "qmp-commands.h" |
| 37 |
#include "qemu/timer.h" |
| 38 |
|
| 39 |
#ifdef CONFIG_BSD
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#include <sys/types.h> |
| 41 |
#include <sys/stat.h> |
| 42 |
#include <sys/ioctl.h> |
| 43 |
#include <sys/queue.h> |
| 44 |
#ifndef __DragonFly__
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#include <sys/disk.h> |
| 46 |
#endif
|
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#endif
|
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|
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#ifdef _WIN32
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#include <windows.h> |
| 51 |
#endif
|
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|
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struct BdrvDirtyBitmap {
|
| 54 |
HBitmap *bitmap; |
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QLIST_ENTRY(BdrvDirtyBitmap) list; |
| 56 |
}; |
| 57 |
|
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#define NOT_DONE 0x7fffffff /* used while emulated sync operation in progress */ |
| 59 |
|
| 60 |
static void bdrv_dev_change_media_cb(BlockDriverState *bs, bool load); |
| 61 |
static BlockDriverAIOCB *bdrv_aio_readv_em(BlockDriverState *bs,
|
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int64_t sector_num, QEMUIOVector *qiov, int nb_sectors,
|
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BlockDriverCompletionFunc *cb, void *opaque);
|
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static BlockDriverAIOCB *bdrv_aio_writev_em(BlockDriverState *bs,
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int64_t sector_num, QEMUIOVector *qiov, int nb_sectors,
|
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BlockDriverCompletionFunc *cb, void *opaque);
|
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static int coroutine_fn bdrv_co_readv_em(BlockDriverState *bs, |
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int64_t sector_num, int nb_sectors,
|
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QEMUIOVector *iov); |
| 70 |
static int coroutine_fn bdrv_co_writev_em(BlockDriverState *bs, |
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int64_t sector_num, int nb_sectors,
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QEMUIOVector *iov); |
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static int coroutine_fn bdrv_co_do_preadv(BlockDriverState *bs, |
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int64_t offset, unsigned int bytes, QEMUIOVector *qiov, |
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BdrvRequestFlags flags); |
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static int coroutine_fn bdrv_co_do_pwritev(BlockDriverState *bs, |
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int64_t offset, unsigned int bytes, QEMUIOVector *qiov, |
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BdrvRequestFlags flags); |
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static BlockDriverAIOCB *bdrv_co_aio_rw_vector(BlockDriverState *bs,
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int64_t sector_num, |
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QEMUIOVector *qiov, |
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int nb_sectors,
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BdrvRequestFlags flags, |
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BlockDriverCompletionFunc *cb, |
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void *opaque,
|
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bool is_write);
|
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static void coroutine_fn bdrv_co_do_rw(void *opaque); |
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static int coroutine_fn bdrv_co_do_write_zeroes(BlockDriverState *bs, |
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int64_t sector_num, int nb_sectors, BdrvRequestFlags flags);
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|
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static QTAILQ_HEAD(, BlockDriverState) bdrv_states =
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QTAILQ_HEAD_INITIALIZER(bdrv_states); |
| 93 |
|
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static QTAILQ_HEAD(, BlockDriverState) graph_bdrv_states =
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QTAILQ_HEAD_INITIALIZER(graph_bdrv_states); |
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|
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static QLIST_HEAD(, BlockDriver) bdrv_drivers =
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QLIST_HEAD_INITIALIZER(bdrv_drivers); |
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|
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/* If non-zero, use only whitelisted block drivers */
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static int use_bdrv_whitelist; |
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|
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#ifdef _WIN32
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static int is_windows_drive_prefix(const char *filename) |
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{
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return (((filename[0] >= 'a' && filename[0] <= 'z') || |
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(filename[0] >= 'A' && filename[0] <= 'Z')) && |
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filename[1] == ':'); |
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} |
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|
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int is_windows_drive(const char *filename) |
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{
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if (is_windows_drive_prefix(filename) &&
|
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filename[2] == '\0') |
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return 1; |
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if (strstart(filename, "\\\\.\\", NULL) || |
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strstart(filename, "//./", NULL)) |
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return 1; |
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return 0; |
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} |
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#endif
|
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|
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/* throttling disk I/O limits */
|
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void bdrv_set_io_limits(BlockDriverState *bs,
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ThrottleConfig *cfg) |
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{
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int i;
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|
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throttle_config(&bs->throttle_state, cfg); |
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|
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for (i = 0; i < 2; i++) { |
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qemu_co_enter_next(&bs->throttled_reqs[i]); |
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} |
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} |
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|
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/* this function drain all the throttled IOs */
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static bool bdrv_start_throttled_reqs(BlockDriverState *bs) |
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{
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bool drained = false; |
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bool enabled = bs->io_limits_enabled;
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int i;
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bs->io_limits_enabled = false;
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|
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for (i = 0; i < 2; i++) { |
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while (qemu_co_enter_next(&bs->throttled_reqs[i])) {
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drained = true;
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} |
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} |
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|
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bs->io_limits_enabled = enabled; |
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|
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return drained;
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} |
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|
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void bdrv_io_limits_disable(BlockDriverState *bs)
|
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{
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bs->io_limits_enabled = false;
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|
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bdrv_start_throttled_reqs(bs); |
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|
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throttle_destroy(&bs->throttle_state); |
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} |
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|
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static void bdrv_throttle_read_timer_cb(void *opaque) |
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{
|
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BlockDriverState *bs = opaque; |
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qemu_co_enter_next(&bs->throttled_reqs[0]);
|
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} |
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|
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static void bdrv_throttle_write_timer_cb(void *opaque) |
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{
|
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BlockDriverState *bs = opaque; |
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qemu_co_enter_next(&bs->throttled_reqs[1]);
|
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} |
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|
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/* should be called before bdrv_set_io_limits if a limit is set */
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void bdrv_io_limits_enable(BlockDriverState *bs)
|
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{
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assert(!bs->io_limits_enabled); |
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throttle_init(&bs->throttle_state, |
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QEMU_CLOCK_VIRTUAL, |
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bdrv_throttle_read_timer_cb, |
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bdrv_throttle_write_timer_cb, |
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bs); |
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bs->io_limits_enabled = true;
|
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} |
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|
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/* This function makes an IO wait if needed
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*
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* @nb_sectors: the number of sectors of the IO
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* @is_write: is the IO a write
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*/
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static void bdrv_io_limits_intercept(BlockDriverState *bs, |
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unsigned int bytes, |
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bool is_write)
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{
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/* does this io must wait */
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bool must_wait = throttle_schedule_timer(&bs->throttle_state, is_write);
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|
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/* if must wait or any request of this type throttled queue the IO */
|
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if (must_wait ||
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!qemu_co_queue_empty(&bs->throttled_reqs[is_write])) {
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qemu_co_queue_wait(&bs->throttled_reqs[is_write]); |
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} |
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|
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/* the IO will be executed, do the accounting */
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throttle_account(&bs->throttle_state, is_write, bytes); |
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|
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|
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/* if the next request must wait -> do nothing */
|
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if (throttle_schedule_timer(&bs->throttle_state, is_write)) {
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return;
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} |
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|
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/* else queue next request for execution */
|
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qemu_co_queue_next(&bs->throttled_reqs[is_write]); |
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} |
| 219 |
|
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size_t bdrv_opt_mem_align(BlockDriverState *bs) |
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{
|
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if (!bs || !bs->drv) {
|
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/* 4k should be on the safe side */
|
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return 4096; |
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} |
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|
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return bs->bl.opt_mem_alignment;
|
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} |
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|
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/* check if the path starts with "<protocol>:" */
|
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static int path_has_protocol(const char *path) |
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{
|
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const char *p; |
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|
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#ifdef _WIN32
|
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if (is_windows_drive(path) ||
|
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is_windows_drive_prefix(path)) {
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return 0; |
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} |
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p = path + strcspn(path, ":/\\");
|
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#else
|
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p = path + strcspn(path, ":/");
|
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#endif
|
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|
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return *p == ':'; |
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} |
| 247 |
|
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int path_is_absolute(const char *path) |
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{
|
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#ifdef _WIN32
|
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/* specific case for names like: "\\.\d:" */
|
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if (is_windows_drive(path) || is_windows_drive_prefix(path)) {
|
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return 1; |
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} |
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return (*path == '/' || *path == '\\'); |
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#else
|
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return (*path == '/'); |
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#endif
|
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} |
| 260 |
|
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/* if filename is absolute, just copy it to dest. Otherwise, build a
|
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path to it by considering it is relative to base_path. URL are
|
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supported. */
|
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void path_combine(char *dest, int dest_size, |
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const char *base_path, |
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const char *filename) |
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{
|
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const char *p, *p1; |
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int len;
|
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|
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if (dest_size <= 0) |
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return;
|
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if (path_is_absolute(filename)) {
|
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pstrcpy(dest, dest_size, filename); |
| 275 |
} else {
|
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p = strchr(base_path, ':');
|
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if (p)
|
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p++; |
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else
|
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p = base_path; |
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p1 = strrchr(base_path, '/');
|
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#ifdef _WIN32
|
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{
|
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const char *p2; |
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p2 = strrchr(base_path, '\\');
|
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if (!p1 || p2 > p1)
|
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p1 = p2; |
| 288 |
} |
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#endif
|
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if (p1)
|
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p1++; |
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else
|
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p1 = base_path; |
| 294 |
if (p1 > p)
|
| 295 |
p = p1; |
| 296 |
len = p - base_path; |
| 297 |
if (len > dest_size - 1) |
| 298 |
len = dest_size - 1;
|
| 299 |
memcpy(dest, base_path, len); |
| 300 |
dest[len] = '\0';
|
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pstrcat(dest, dest_size, filename); |
| 302 |
} |
| 303 |
} |
| 304 |
|
| 305 |
void bdrv_get_full_backing_filename(BlockDriverState *bs, char *dest, size_t sz) |
| 306 |
{
|
| 307 |
if (bs->backing_file[0] == '\0' || path_has_protocol(bs->backing_file)) { |
| 308 |
pstrcpy(dest, sz, bs->backing_file); |
| 309 |
} else {
|
| 310 |
path_combine(dest, sz, bs->filename, bs->backing_file); |
| 311 |
} |
| 312 |
} |
| 313 |
|
| 314 |
void bdrv_register(BlockDriver *bdrv)
|
| 315 |
{
|
| 316 |
/* Block drivers without coroutine functions need emulation */
|
| 317 |
if (!bdrv->bdrv_co_readv) {
|
| 318 |
bdrv->bdrv_co_readv = bdrv_co_readv_em; |
| 319 |
bdrv->bdrv_co_writev = bdrv_co_writev_em; |
| 320 |
|
| 321 |
/* bdrv_co_readv_em()/brdv_co_writev_em() work in terms of aio, so if
|
| 322 |
* the block driver lacks aio we need to emulate that too.
|
| 323 |
*/
|
| 324 |
if (!bdrv->bdrv_aio_readv) {
|
| 325 |
/* add AIO emulation layer */
|
| 326 |
bdrv->bdrv_aio_readv = bdrv_aio_readv_em; |
| 327 |
bdrv->bdrv_aio_writev = bdrv_aio_writev_em; |
| 328 |
} |
| 329 |
} |
| 330 |
|
| 331 |
QLIST_INSERT_HEAD(&bdrv_drivers, bdrv, list); |
| 332 |
} |
| 333 |
|
| 334 |
/* create a new block device (by default it is empty) */
|
| 335 |
BlockDriverState *bdrv_new(const char *device_name) |
| 336 |
{
|
| 337 |
BlockDriverState *bs; |
| 338 |
|
| 339 |
bs = g_malloc0(sizeof(BlockDriverState));
|
| 340 |
QLIST_INIT(&bs->dirty_bitmaps); |
| 341 |
pstrcpy(bs->device_name, sizeof(bs->device_name), device_name);
|
| 342 |
if (device_name[0] != '\0') { |
| 343 |
QTAILQ_INSERT_TAIL(&bdrv_states, bs, device_list); |
| 344 |
} |
| 345 |
bdrv_iostatus_disable(bs); |
| 346 |
notifier_list_init(&bs->close_notifiers); |
| 347 |
notifier_with_return_list_init(&bs->before_write_notifiers); |
| 348 |
qemu_co_queue_init(&bs->throttled_reqs[0]);
|
| 349 |
qemu_co_queue_init(&bs->throttled_reqs[1]);
|
| 350 |
bs->refcnt = 1;
|
| 351 |
|
| 352 |
return bs;
|
| 353 |
} |
| 354 |
|
| 355 |
void bdrv_add_close_notifier(BlockDriverState *bs, Notifier *notify)
|
| 356 |
{
|
| 357 |
notifier_list_add(&bs->close_notifiers, notify); |
| 358 |
} |
| 359 |
|
| 360 |
BlockDriver *bdrv_find_format(const char *format_name) |
| 361 |
{
|
| 362 |
BlockDriver *drv1; |
| 363 |
QLIST_FOREACH(drv1, &bdrv_drivers, list) {
|
| 364 |
if (!strcmp(drv1->format_name, format_name)) {
|
| 365 |
return drv1;
|
| 366 |
} |
| 367 |
} |
| 368 |
return NULL; |
| 369 |
} |
| 370 |
|
| 371 |
static int bdrv_is_whitelisted(BlockDriver *drv, bool read_only) |
| 372 |
{
|
| 373 |
static const char *whitelist_rw[] = { |
| 374 |
CONFIG_BDRV_RW_WHITELIST |
| 375 |
}; |
| 376 |
static const char *whitelist_ro[] = { |
| 377 |
CONFIG_BDRV_RO_WHITELIST |
| 378 |
}; |
| 379 |
const char **p; |
| 380 |
|
| 381 |
if (!whitelist_rw[0] && !whitelist_ro[0]) { |
| 382 |
return 1; /* no whitelist, anything goes */ |
| 383 |
} |
| 384 |
|
| 385 |
for (p = whitelist_rw; *p; p++) {
|
| 386 |
if (!strcmp(drv->format_name, *p)) {
|
| 387 |
return 1; |
| 388 |
} |
| 389 |
} |
| 390 |
if (read_only) {
|
| 391 |
for (p = whitelist_ro; *p; p++) {
|
| 392 |
if (!strcmp(drv->format_name, *p)) {
|
| 393 |
return 1; |
| 394 |
} |
| 395 |
} |
| 396 |
} |
| 397 |
return 0; |
| 398 |
} |
| 399 |
|
| 400 |
BlockDriver *bdrv_find_whitelisted_format(const char *format_name, |
| 401 |
bool read_only)
|
| 402 |
{
|
| 403 |
BlockDriver *drv = bdrv_find_format(format_name); |
| 404 |
return drv && bdrv_is_whitelisted(drv, read_only) ? drv : NULL; |
| 405 |
} |
| 406 |
|
| 407 |
typedef struct CreateCo { |
| 408 |
BlockDriver *drv; |
| 409 |
char *filename;
|
| 410 |
QEMUOptionParameter *options; |
| 411 |
int ret;
|
| 412 |
Error *err; |
| 413 |
} CreateCo; |
| 414 |
|
| 415 |
static void coroutine_fn bdrv_create_co_entry(void *opaque) |
| 416 |
{
|
| 417 |
Error *local_err = NULL;
|
| 418 |
int ret;
|
| 419 |
|
| 420 |
CreateCo *cco = opaque; |
| 421 |
assert(cco->drv); |
| 422 |
|
| 423 |
ret = cco->drv->bdrv_create(cco->filename, cco->options, &local_err); |
| 424 |
if (local_err) {
|
| 425 |
error_propagate(&cco->err, local_err); |
| 426 |
} |
| 427 |
cco->ret = ret; |
| 428 |
} |
| 429 |
|
| 430 |
int bdrv_create(BlockDriver *drv, const char* filename, |
| 431 |
QEMUOptionParameter *options, Error **errp) |
| 432 |
{
|
| 433 |
int ret;
|
| 434 |
|
| 435 |
Coroutine *co; |
| 436 |
CreateCo cco = {
|
| 437 |
.drv = drv, |
| 438 |
.filename = g_strdup(filename), |
| 439 |
.options = options, |
| 440 |
.ret = NOT_DONE, |
| 441 |
.err = NULL,
|
| 442 |
}; |
| 443 |
|
| 444 |
if (!drv->bdrv_create) {
|
| 445 |
error_setg(errp, "Driver '%s' does not support image creation", drv->format_name);
|
| 446 |
ret = -ENOTSUP; |
| 447 |
goto out;
|
| 448 |
} |
| 449 |
|
| 450 |
if (qemu_in_coroutine()) {
|
| 451 |
/* Fast-path if already in coroutine context */
|
| 452 |
bdrv_create_co_entry(&cco); |
| 453 |
} else {
|
| 454 |
co = qemu_coroutine_create(bdrv_create_co_entry); |
| 455 |
qemu_coroutine_enter(co, &cco); |
| 456 |
while (cco.ret == NOT_DONE) {
|
| 457 |
qemu_aio_wait(); |
| 458 |
} |
| 459 |
} |
| 460 |
|
| 461 |
ret = cco.ret; |
| 462 |
if (ret < 0) { |
| 463 |
if (cco.err) {
|
| 464 |
error_propagate(errp, cco.err); |
| 465 |
} else {
|
| 466 |
error_setg_errno(errp, -ret, "Could not create image");
|
| 467 |
} |
| 468 |
} |
| 469 |
|
| 470 |
out:
|
| 471 |
g_free(cco.filename); |
| 472 |
return ret;
|
| 473 |
} |
| 474 |
|
| 475 |
int bdrv_create_file(const char* filename, QEMUOptionParameter *options, |
| 476 |
Error **errp) |
| 477 |
{
|
| 478 |
BlockDriver *drv; |
| 479 |
Error *local_err = NULL;
|
| 480 |
int ret;
|
| 481 |
|
| 482 |
drv = bdrv_find_protocol(filename, true);
|
| 483 |
if (drv == NULL) { |
| 484 |
error_setg(errp, "Could not find protocol for file '%s'", filename);
|
| 485 |
return -ENOENT;
|
| 486 |
} |
| 487 |
|
| 488 |
ret = bdrv_create(drv, filename, options, &local_err); |
| 489 |
if (local_err) {
|
| 490 |
error_propagate(errp, local_err); |
| 491 |
} |
| 492 |
return ret;
|
| 493 |
} |
| 494 |
|
| 495 |
int bdrv_refresh_limits(BlockDriverState *bs)
|
| 496 |
{
|
| 497 |
BlockDriver *drv = bs->drv; |
| 498 |
|
| 499 |
memset(&bs->bl, 0, sizeof(bs->bl)); |
| 500 |
|
| 501 |
if (!drv) {
|
| 502 |
return 0; |
| 503 |
} |
| 504 |
|
| 505 |
/* Take some limits from the children as a default */
|
| 506 |
if (bs->file) {
|
| 507 |
bdrv_refresh_limits(bs->file); |
| 508 |
bs->bl.opt_transfer_length = bs->file->bl.opt_transfer_length; |
| 509 |
bs->bl.opt_mem_alignment = bs->file->bl.opt_mem_alignment; |
| 510 |
} else {
|
| 511 |
bs->bl.opt_mem_alignment = 512;
|
| 512 |
} |
| 513 |
|
| 514 |
if (bs->backing_hd) {
|
| 515 |
bdrv_refresh_limits(bs->backing_hd); |
| 516 |
bs->bl.opt_transfer_length = |
| 517 |
MAX(bs->bl.opt_transfer_length, |
| 518 |
bs->backing_hd->bl.opt_transfer_length); |
| 519 |
bs->bl.opt_mem_alignment = |
| 520 |
MAX(bs->bl.opt_mem_alignment, |
| 521 |
bs->backing_hd->bl.opt_mem_alignment); |
| 522 |
} |
| 523 |
|
| 524 |
/* Then let the driver override it */
|
| 525 |
if (drv->bdrv_refresh_limits) {
|
| 526 |
return drv->bdrv_refresh_limits(bs);
|
| 527 |
} |
| 528 |
|
| 529 |
return 0; |
| 530 |
} |
| 531 |
|
| 532 |
/*
|
| 533 |
* Create a uniquely-named empty temporary file.
|
| 534 |
* Return 0 upon success, otherwise a negative errno value.
|
| 535 |
*/
|
| 536 |
int get_tmp_filename(char *filename, int size) |
| 537 |
{
|
| 538 |
#ifdef _WIN32
|
| 539 |
char temp_dir[MAX_PATH];
|
| 540 |
/* GetTempFileName requires that its output buffer (4th param)
|
| 541 |
have length MAX_PATH or greater. */
|
| 542 |
assert(size >= MAX_PATH); |
| 543 |
return (GetTempPath(MAX_PATH, temp_dir)
|
| 544 |
&& GetTempFileName(temp_dir, "qem", 0, filename) |
| 545 |
? 0 : -GetLastError());
|
| 546 |
#else
|
| 547 |
int fd;
|
| 548 |
const char *tmpdir; |
| 549 |
tmpdir = getenv("TMPDIR");
|
| 550 |
if (!tmpdir)
|
| 551 |
tmpdir = "/tmp";
|
| 552 |
if (snprintf(filename, size, "%s/vl.XXXXXX", tmpdir) >= size) { |
| 553 |
return -EOVERFLOW;
|
| 554 |
} |
| 555 |
fd = mkstemp(filename); |
| 556 |
if (fd < 0) { |
| 557 |
return -errno;
|
| 558 |
} |
| 559 |
if (close(fd) != 0) { |
| 560 |
unlink(filename); |
| 561 |
return -errno;
|
| 562 |
} |
| 563 |
return 0; |
| 564 |
#endif
|
| 565 |
} |
| 566 |
|
| 567 |
/*
|
| 568 |
* Detect host devices. By convention, /dev/cdrom[N] is always
|
| 569 |
* recognized as a host CDROM.
|
| 570 |
*/
|
| 571 |
static BlockDriver *find_hdev_driver(const char *filename) |
| 572 |
{
|
| 573 |
int score_max = 0, score; |
| 574 |
BlockDriver *drv = NULL, *d;
|
| 575 |
|
| 576 |
QLIST_FOREACH(d, &bdrv_drivers, list) {
|
| 577 |
if (d->bdrv_probe_device) {
|
| 578 |
score = d->bdrv_probe_device(filename); |
| 579 |
if (score > score_max) {
|
| 580 |
score_max = score; |
| 581 |
drv = d; |
| 582 |
} |
| 583 |
} |
| 584 |
} |
| 585 |
|
| 586 |
return drv;
|
| 587 |
} |
| 588 |
|
| 589 |
BlockDriver *bdrv_find_protocol(const char *filename, |
| 590 |
bool allow_protocol_prefix)
|
| 591 |
{
|
| 592 |
BlockDriver *drv1; |
| 593 |
char protocol[128]; |
| 594 |
int len;
|
| 595 |
const char *p; |
| 596 |
|
| 597 |
/* TODO Drivers without bdrv_file_open must be specified explicitly */
|
| 598 |
|
| 599 |
/*
|
| 600 |
* XXX(hch): we really should not let host device detection
|
| 601 |
* override an explicit protocol specification, but moving this
|
| 602 |
* later breaks access to device names with colons in them.
|
| 603 |
* Thanks to the brain-dead persistent naming schemes on udev-
|
| 604 |
* based Linux systems those actually are quite common.
|
| 605 |
*/
|
| 606 |
drv1 = find_hdev_driver(filename); |
| 607 |
if (drv1) {
|
| 608 |
return drv1;
|
| 609 |
} |
| 610 |
|
| 611 |
if (!path_has_protocol(filename) || !allow_protocol_prefix) {
|
| 612 |
return bdrv_find_format("file"); |
| 613 |
} |
| 614 |
|
| 615 |
p = strchr(filename, ':');
|
| 616 |
assert(p != NULL);
|
| 617 |
len = p - filename; |
| 618 |
if (len > sizeof(protocol) - 1) |
| 619 |
len = sizeof(protocol) - 1; |
| 620 |
memcpy(protocol, filename, len); |
| 621 |
protocol[len] = '\0';
|
| 622 |
QLIST_FOREACH(drv1, &bdrv_drivers, list) {
|
| 623 |
if (drv1->protocol_name &&
|
| 624 |
!strcmp(drv1->protocol_name, protocol)) {
|
| 625 |
return drv1;
|
| 626 |
} |
| 627 |
} |
| 628 |
return NULL; |
| 629 |
} |
| 630 |
|
| 631 |
static int find_image_format(BlockDriverState *bs, const char *filename, |
| 632 |
BlockDriver **pdrv, Error **errp) |
| 633 |
{
|
| 634 |
int score, score_max;
|
| 635 |
BlockDriver *drv1, *drv; |
| 636 |
uint8_t buf[2048];
|
| 637 |
int ret = 0; |
| 638 |
|
| 639 |
/* Return the raw BlockDriver * to scsi-generic devices or empty drives */
|
| 640 |
if (bs->sg || !bdrv_is_inserted(bs) || bdrv_getlength(bs) == 0) { |
| 641 |
drv = bdrv_find_format("raw");
|
| 642 |
if (!drv) {
|
| 643 |
error_setg(errp, "Could not find raw image format");
|
| 644 |
ret = -ENOENT; |
| 645 |
} |
| 646 |
*pdrv = drv; |
| 647 |
return ret;
|
| 648 |
} |
| 649 |
|
| 650 |
ret = bdrv_pread(bs, 0, buf, sizeof(buf)); |
| 651 |
if (ret < 0) { |
| 652 |
error_setg_errno(errp, -ret, "Could not read image for determining its "
|
| 653 |
"format");
|
| 654 |
*pdrv = NULL;
|
| 655 |
return ret;
|
| 656 |
} |
| 657 |
|
| 658 |
score_max = 0;
|
| 659 |
drv = NULL;
|
| 660 |
QLIST_FOREACH(drv1, &bdrv_drivers, list) {
|
| 661 |
if (drv1->bdrv_probe) {
|
| 662 |
score = drv1->bdrv_probe(buf, ret, filename); |
| 663 |
if (score > score_max) {
|
| 664 |
score_max = score; |
| 665 |
drv = drv1; |
| 666 |
} |
| 667 |
} |
| 668 |
} |
| 669 |
if (!drv) {
|
| 670 |
error_setg(errp, "Could not determine image format: No compatible "
|
| 671 |
"driver found");
|
| 672 |
ret = -ENOENT; |
| 673 |
} |
| 674 |
*pdrv = drv; |
| 675 |
return ret;
|
| 676 |
} |
| 677 |
|
| 678 |
/**
|
| 679 |
* Set the current 'total_sectors' value
|
| 680 |
*/
|
| 681 |
static int refresh_total_sectors(BlockDriverState *bs, int64_t hint) |
| 682 |
{
|
| 683 |
BlockDriver *drv = bs->drv; |
| 684 |
|
| 685 |
/* Do not attempt drv->bdrv_getlength() on scsi-generic devices */
|
| 686 |
if (bs->sg)
|
| 687 |
return 0; |
| 688 |
|
| 689 |
/* query actual device if possible, otherwise just trust the hint */
|
| 690 |
if (drv->bdrv_getlength) {
|
| 691 |
int64_t length = drv->bdrv_getlength(bs); |
| 692 |
if (length < 0) { |
| 693 |
return length;
|
| 694 |
} |
| 695 |
hint = DIV_ROUND_UP(length, BDRV_SECTOR_SIZE); |
| 696 |
} |
| 697 |
|
| 698 |
bs->total_sectors = hint; |
| 699 |
return 0; |
| 700 |
} |
| 701 |
|
| 702 |
/**
|
| 703 |
* Set open flags for a given discard mode
|
| 704 |
*
|
| 705 |
* Return 0 on success, -1 if the discard mode was invalid.
|
| 706 |
*/
|
| 707 |
int bdrv_parse_discard_flags(const char *mode, int *flags) |
| 708 |
{
|
| 709 |
*flags &= ~BDRV_O_UNMAP; |
| 710 |
|
| 711 |
if (!strcmp(mode, "off") || !strcmp(mode, "ignore")) { |
| 712 |
/* do nothing */
|
| 713 |
} else if (!strcmp(mode, "on") || !strcmp(mode, "unmap")) { |
| 714 |
*flags |= BDRV_O_UNMAP; |
| 715 |
} else {
|
| 716 |
return -1; |
| 717 |
} |
| 718 |
|
| 719 |
return 0; |
| 720 |
} |
| 721 |
|
| 722 |
/**
|
| 723 |
* Set open flags for a given cache mode
|
| 724 |
*
|
| 725 |
* Return 0 on success, -1 if the cache mode was invalid.
|
| 726 |
*/
|
| 727 |
int bdrv_parse_cache_flags(const char *mode, int *flags) |
| 728 |
{
|
| 729 |
*flags &= ~BDRV_O_CACHE_MASK; |
| 730 |
|
| 731 |
if (!strcmp(mode, "off") || !strcmp(mode, "none")) { |
| 732 |
*flags |= BDRV_O_NOCACHE | BDRV_O_CACHE_WB; |
| 733 |
} else if (!strcmp(mode, "directsync")) { |
| 734 |
*flags |= BDRV_O_NOCACHE; |
| 735 |
} else if (!strcmp(mode, "writeback")) { |
| 736 |
*flags |= BDRV_O_CACHE_WB; |
| 737 |
} else if (!strcmp(mode, "unsafe")) { |
| 738 |
*flags |= BDRV_O_CACHE_WB; |
| 739 |
*flags |= BDRV_O_NO_FLUSH; |
| 740 |
} else if (!strcmp(mode, "writethrough")) { |
| 741 |
/* this is the default */
|
| 742 |
} else {
|
| 743 |
return -1; |
| 744 |
} |
| 745 |
|
| 746 |
return 0; |
| 747 |
} |
| 748 |
|
| 749 |
/**
|
| 750 |
* The copy-on-read flag is actually a reference count so multiple users may
|
| 751 |
* use the feature without worrying about clobbering its previous state.
|
| 752 |
* Copy-on-read stays enabled until all users have called to disable it.
|
| 753 |
*/
|
| 754 |
void bdrv_enable_copy_on_read(BlockDriverState *bs)
|
| 755 |
{
|
| 756 |
bs->copy_on_read++; |
| 757 |
} |
| 758 |
|
| 759 |
void bdrv_disable_copy_on_read(BlockDriverState *bs)
|
| 760 |
{
|
| 761 |
assert(bs->copy_on_read > 0);
|
| 762 |
bs->copy_on_read--; |
| 763 |
} |
| 764 |
|
| 765 |
static int bdrv_open_flags(BlockDriverState *bs, int flags) |
| 766 |
{
|
| 767 |
int open_flags = flags | BDRV_O_CACHE_WB;
|
| 768 |
|
| 769 |
/*
|
| 770 |
* Clear flags that are internal to the block layer before opening the
|
| 771 |
* image.
|
| 772 |
*/
|
| 773 |
open_flags &= ~(BDRV_O_SNAPSHOT | BDRV_O_NO_BACKING); |
| 774 |
|
| 775 |
/*
|
| 776 |
* Snapshots should be writable.
|
| 777 |
*/
|
| 778 |
if (bs->is_temporary) {
|
| 779 |
open_flags |= BDRV_O_RDWR; |
| 780 |
} |
| 781 |
|
| 782 |
return open_flags;
|
| 783 |
} |
| 784 |
|
| 785 |
static int bdrv_assign_node_name(BlockDriverState *bs, |
| 786 |
const char *node_name, |
| 787 |
Error **errp) |
| 788 |
{
|
| 789 |
if (!node_name) {
|
| 790 |
return 0; |
| 791 |
} |
| 792 |
|
| 793 |
/* empty string node name is invalid */
|
| 794 |
if (node_name[0] == '\0') { |
| 795 |
error_setg(errp, "Empty node name");
|
| 796 |
return -EINVAL;
|
| 797 |
} |
| 798 |
|
| 799 |
/* takes care of avoiding namespaces collisions */
|
| 800 |
if (bdrv_find(node_name)) {
|
| 801 |
error_setg(errp, "node-name=%s is conflicting with a device id",
|
| 802 |
node_name); |
| 803 |
return -EINVAL;
|
| 804 |
} |
| 805 |
|
| 806 |
/* takes care of avoiding duplicates node names */
|
| 807 |
if (bdrv_find_node(node_name)) {
|
| 808 |
error_setg(errp, "Duplicate node name");
|
| 809 |
return -EINVAL;
|
| 810 |
} |
| 811 |
|
| 812 |
/* copy node name into the bs and insert it into the graph list */
|
| 813 |
pstrcpy(bs->node_name, sizeof(bs->node_name), node_name);
|
| 814 |
QTAILQ_INSERT_TAIL(&graph_bdrv_states, bs, node_list); |
| 815 |
|
| 816 |
return 0; |
| 817 |
} |
| 818 |
|
| 819 |
/*
|
| 820 |
* Common part for opening disk images and files
|
| 821 |
*
|
| 822 |
* Removes all processed options from *options.
|
| 823 |
*/
|
| 824 |
static int bdrv_open_common(BlockDriverState *bs, BlockDriverState *file, |
| 825 |
QDict *options, int flags, BlockDriver *drv, Error **errp)
|
| 826 |
{
|
| 827 |
int ret, open_flags;
|
| 828 |
const char *filename; |
| 829 |
const char *node_name = NULL; |
| 830 |
Error *local_err = NULL;
|
| 831 |
|
| 832 |
assert(drv != NULL);
|
| 833 |
assert(bs->file == NULL);
|
| 834 |
assert(options != NULL && bs->options != options);
|
| 835 |
|
| 836 |
if (file != NULL) { |
| 837 |
filename = file->filename; |
| 838 |
} else {
|
| 839 |
filename = qdict_get_try_str(options, "filename");
|
| 840 |
} |
| 841 |
|
| 842 |
if (drv->bdrv_needs_filename && !filename) {
|
| 843 |
error_setg(errp, "The '%s' block driver requires a file name",
|
| 844 |
drv->format_name); |
| 845 |
return -EINVAL;
|
| 846 |
} |
| 847 |
|
| 848 |
trace_bdrv_open_common(bs, filename ?: "", flags, drv->format_name);
|
| 849 |
|
| 850 |
node_name = qdict_get_try_str(options, "node-name");
|
| 851 |
ret = bdrv_assign_node_name(bs, node_name, errp); |
| 852 |
if (ret < 0) { |
| 853 |
return ret;
|
| 854 |
} |
| 855 |
qdict_del(options, "node-name");
|
| 856 |
|
| 857 |
/* bdrv_open() with directly using a protocol as drv. This layer is already
|
| 858 |
* opened, so assign it to bs (while file becomes a closed BlockDriverState)
|
| 859 |
* and return immediately. */
|
| 860 |
if (file != NULL && drv->bdrv_file_open) { |
| 861 |
bdrv_swap(file, bs); |
| 862 |
return 0; |
| 863 |
} |
| 864 |
|
| 865 |
bs->open_flags = flags; |
| 866 |
bs->guest_block_size = 512;
|
| 867 |
bs->request_alignment = 512;
|
| 868 |
bs->zero_beyond_eof = true;
|
| 869 |
open_flags = bdrv_open_flags(bs, flags); |
| 870 |
bs->read_only = !(open_flags & BDRV_O_RDWR); |
| 871 |
|
| 872 |
if (use_bdrv_whitelist && !bdrv_is_whitelisted(drv, bs->read_only)) {
|
| 873 |
error_setg(errp, |
| 874 |
!bs->read_only && bdrv_is_whitelisted(drv, true)
|
| 875 |
? "Driver '%s' can only be used for read-only devices"
|
| 876 |
: "Driver '%s' is not whitelisted",
|
| 877 |
drv->format_name); |
| 878 |
return -ENOTSUP;
|
| 879 |
} |
| 880 |
|
| 881 |
assert(bs->copy_on_read == 0); /* bdrv_new() and bdrv_close() make it so */ |
| 882 |
if (flags & BDRV_O_COPY_ON_READ) {
|
| 883 |
if (!bs->read_only) {
|
| 884 |
bdrv_enable_copy_on_read(bs); |
| 885 |
} else {
|
| 886 |
error_setg(errp, "Can't use copy-on-read on read-only device");
|
| 887 |
return -EINVAL;
|
| 888 |
} |
| 889 |
} |
| 890 |
|
| 891 |
if (filename != NULL) { |
| 892 |
pstrcpy(bs->filename, sizeof(bs->filename), filename);
|
| 893 |
} else {
|
| 894 |
bs->filename[0] = '\0'; |
| 895 |
} |
| 896 |
|
| 897 |
bs->drv = drv; |
| 898 |
bs->opaque = g_malloc0(drv->instance_size); |
| 899 |
|
| 900 |
bs->enable_write_cache = !!(flags & BDRV_O_CACHE_WB); |
| 901 |
|
| 902 |
/* Open the image, either directly or using a protocol */
|
| 903 |
if (drv->bdrv_file_open) {
|
| 904 |
assert(file == NULL);
|
| 905 |
assert(!drv->bdrv_needs_filename || filename != NULL);
|
| 906 |
ret = drv->bdrv_file_open(bs, options, open_flags, &local_err); |
| 907 |
} else {
|
| 908 |
if (file == NULL) { |
| 909 |
error_setg(errp, "Can't use '%s' as a block driver for the "
|
| 910 |
"protocol level", drv->format_name);
|
| 911 |
ret = -EINVAL; |
| 912 |
goto free_and_fail;
|
| 913 |
} |
| 914 |
bs->file = file; |
| 915 |
ret = drv->bdrv_open(bs, options, open_flags, &local_err); |
| 916 |
} |
| 917 |
|
| 918 |
if (ret < 0) { |
| 919 |
if (local_err) {
|
| 920 |
error_propagate(errp, local_err); |
| 921 |
} else if (bs->filename[0]) { |
| 922 |
error_setg_errno(errp, -ret, "Could not open '%s'", bs->filename);
|
| 923 |
} else {
|
| 924 |
error_setg_errno(errp, -ret, "Could not open image");
|
| 925 |
} |
| 926 |
goto free_and_fail;
|
| 927 |
} |
| 928 |
|
| 929 |
ret = refresh_total_sectors(bs, bs->total_sectors); |
| 930 |
if (ret < 0) { |
| 931 |
error_setg_errno(errp, -ret, "Could not refresh total sector count");
|
| 932 |
goto free_and_fail;
|
| 933 |
} |
| 934 |
|
| 935 |
bdrv_refresh_limits(bs); |
| 936 |
assert(bdrv_opt_mem_align(bs) != 0);
|
| 937 |
assert(bs->request_alignment != 0);
|
| 938 |
|
| 939 |
#ifndef _WIN32
|
| 940 |
if (bs->is_temporary) {
|
| 941 |
assert(bs->filename[0] != '\0'); |
| 942 |
unlink(bs->filename); |
| 943 |
} |
| 944 |
#endif
|
| 945 |
return 0; |
| 946 |
|
| 947 |
free_and_fail:
|
| 948 |
bs->file = NULL;
|
| 949 |
g_free(bs->opaque); |
| 950 |
bs->opaque = NULL;
|
| 951 |
bs->drv = NULL;
|
| 952 |
return ret;
|
| 953 |
} |
| 954 |
|
| 955 |
/*
|
| 956 |
* Opens a file using a protocol (file, host_device, nbd, ...)
|
| 957 |
*
|
| 958 |
* options is a QDict of options to pass to the block drivers, or NULL for an
|
| 959 |
* empty set of options. The reference to the QDict belongs to the block layer
|
| 960 |
* after the call (even on failure), so if the caller intends to reuse the
|
| 961 |
* dictionary, it needs to use QINCREF() before calling bdrv_file_open.
|
| 962 |
*/
|
| 963 |
int bdrv_file_open(BlockDriverState **pbs, const char *filename, |
| 964 |
const char *reference, QDict *options, int flags, |
| 965 |
Error **errp) |
| 966 |
{
|
| 967 |
BlockDriverState *bs = NULL;
|
| 968 |
BlockDriver *drv; |
| 969 |
const char *drvname; |
| 970 |
bool allow_protocol_prefix = false; |
| 971 |
Error *local_err = NULL;
|
| 972 |
int ret;
|
| 973 |
|
| 974 |
/* NULL means an empty set of options */
|
| 975 |
if (options == NULL) { |
| 976 |
options = qdict_new(); |
| 977 |
} |
| 978 |
|
| 979 |
if (reference) {
|
| 980 |
if (filename || qdict_size(options)) {
|
| 981 |
error_setg(errp, "Cannot reference an existing block device with "
|
| 982 |
"additional options or a new filename");
|
| 983 |
return -EINVAL;
|
| 984 |
} |
| 985 |
QDECREF(options); |
| 986 |
|
| 987 |
bs = bdrv_lookup_bs(reference, reference, errp); |
| 988 |
if (!bs) {
|
| 989 |
return -ENODEV;
|
| 990 |
} |
| 991 |
bdrv_ref(bs); |
| 992 |
*pbs = bs; |
| 993 |
return 0; |
| 994 |
} |
| 995 |
|
| 996 |
bs = bdrv_new("");
|
| 997 |
bs->options = options; |
| 998 |
options = qdict_clone_shallow(options); |
| 999 |
|
| 1000 |
/* Fetch the file name from the options QDict if necessary */
|
| 1001 |
if (!filename) {
|
| 1002 |
filename = qdict_get_try_str(options, "filename");
|
| 1003 |
} else if (filename && !qdict_haskey(options, "filename")) { |
| 1004 |
qdict_put(options, "filename", qstring_from_str(filename));
|
| 1005 |
allow_protocol_prefix = true;
|
| 1006 |
} else {
|
| 1007 |
error_setg(errp, "Can't specify 'file' and 'filename' options at the "
|
| 1008 |
"same time");
|
| 1009 |
ret = -EINVAL; |
| 1010 |
goto fail;
|
| 1011 |
} |
| 1012 |
|
| 1013 |
/* Find the right block driver */
|
| 1014 |
drvname = qdict_get_try_str(options, "driver");
|
| 1015 |
if (drvname) {
|
| 1016 |
drv = bdrv_find_format(drvname); |
| 1017 |
if (!drv) {
|
| 1018 |
error_setg(errp, "Unknown driver '%s'", drvname);
|
| 1019 |
} |
| 1020 |
qdict_del(options, "driver");
|
| 1021 |
} else if (filename) { |
| 1022 |
drv = bdrv_find_protocol(filename, allow_protocol_prefix); |
| 1023 |
if (!drv) {
|
| 1024 |
error_setg(errp, "Unknown protocol");
|
| 1025 |
} |
| 1026 |
} else {
|
| 1027 |
error_setg(errp, "Must specify either driver or file");
|
| 1028 |
drv = NULL;
|
| 1029 |
} |
| 1030 |
|
| 1031 |
if (!drv) {
|
| 1032 |
/* errp has been set already */
|
| 1033 |
ret = -ENOENT; |
| 1034 |
goto fail;
|
| 1035 |
} |
| 1036 |
|
| 1037 |
/* Parse the filename and open it */
|
| 1038 |
if (drv->bdrv_parse_filename && filename) {
|
| 1039 |
drv->bdrv_parse_filename(filename, options, &local_err); |
| 1040 |
if (local_err) {
|
| 1041 |
error_propagate(errp, local_err); |
| 1042 |
ret = -EINVAL; |
| 1043 |
goto fail;
|
| 1044 |
} |
| 1045 |
qdict_del(options, "filename");
|
| 1046 |
} |
| 1047 |
|
| 1048 |
if (!drv->bdrv_file_open) {
|
| 1049 |
ret = bdrv_open(&bs, filename, options, flags, drv, &local_err); |
| 1050 |
options = NULL;
|
| 1051 |
} else {
|
| 1052 |
ret = bdrv_open_common(bs, NULL, options, flags, drv, &local_err);
|
| 1053 |
} |
| 1054 |
if (ret < 0) { |
| 1055 |
error_propagate(errp, local_err); |
| 1056 |
goto fail;
|
| 1057 |
} |
| 1058 |
|
| 1059 |
/* Check if any unknown options were used */
|
| 1060 |
if (options && (qdict_size(options) != 0)) { |
| 1061 |
const QDictEntry *entry = qdict_first(options);
|
| 1062 |
error_setg(errp, "Block protocol '%s' doesn't support the option '%s'",
|
| 1063 |
drv->format_name, entry->key); |
| 1064 |
ret = -EINVAL; |
| 1065 |
goto fail;
|
| 1066 |
} |
| 1067 |
QDECREF(options); |
| 1068 |
|
| 1069 |
bs->growable = 1;
|
| 1070 |
*pbs = bs; |
| 1071 |
return 0; |
| 1072 |
|
| 1073 |
fail:
|
| 1074 |
QDECREF(options); |
| 1075 |
if (!bs->drv) {
|
| 1076 |
QDECREF(bs->options); |
| 1077 |
} |
| 1078 |
bdrv_unref(bs); |
| 1079 |
return ret;
|
| 1080 |
} |
| 1081 |
|
| 1082 |
/*
|
| 1083 |
* Opens the backing file for a BlockDriverState if not yet open
|
| 1084 |
*
|
| 1085 |
* options is a QDict of options to pass to the block drivers, or NULL for an
|
| 1086 |
* empty set of options. The reference to the QDict is transferred to this
|
| 1087 |
* function (even on failure), so if the caller intends to reuse the dictionary,
|
| 1088 |
* it needs to use QINCREF() before calling bdrv_file_open.
|
| 1089 |
*/
|
| 1090 |
int bdrv_open_backing_file(BlockDriverState *bs, QDict *options, Error **errp)
|
| 1091 |
{
|
| 1092 |
char backing_filename[PATH_MAX];
|
| 1093 |
int back_flags, ret;
|
| 1094 |
BlockDriver *back_drv = NULL;
|
| 1095 |
Error *local_err = NULL;
|
| 1096 |
|
| 1097 |
if (bs->backing_hd != NULL) { |
| 1098 |
QDECREF(options); |
| 1099 |
return 0; |
| 1100 |
} |
| 1101 |
|
| 1102 |
/* NULL means an empty set of options */
|
| 1103 |
if (options == NULL) { |
| 1104 |
options = qdict_new(); |
| 1105 |
} |
| 1106 |
|
| 1107 |
bs->open_flags &= ~BDRV_O_NO_BACKING; |
| 1108 |
if (qdict_haskey(options, "file.filename")) { |
| 1109 |
backing_filename[0] = '\0'; |
| 1110 |
} else if (bs->backing_file[0] == '\0' && qdict_size(options) == 0) { |
| 1111 |
QDECREF(options); |
| 1112 |
return 0; |
| 1113 |
} else {
|
| 1114 |
bdrv_get_full_backing_filename(bs, backing_filename, |
| 1115 |
sizeof(backing_filename));
|
| 1116 |
} |
| 1117 |
|
| 1118 |
if (bs->backing_format[0] != '\0') { |
| 1119 |
back_drv = bdrv_find_format(bs->backing_format); |
| 1120 |
} |
| 1121 |
|
| 1122 |
/* backing files always opened read-only */
|
| 1123 |
back_flags = bs->open_flags & ~(BDRV_O_RDWR | BDRV_O_SNAPSHOT | |
| 1124 |
BDRV_O_COPY_ON_READ); |
| 1125 |
|
| 1126 |
assert(bs->backing_hd == NULL);
|
| 1127 |
ret = bdrv_open(&bs->backing_hd, |
| 1128 |
*backing_filename ? backing_filename : NULL, options,
|
| 1129 |
back_flags, back_drv, &local_err); |
| 1130 |
if (ret < 0) { |
| 1131 |
bs->backing_hd = NULL;
|
| 1132 |
bs->open_flags |= BDRV_O_NO_BACKING; |
| 1133 |
error_setg(errp, "Could not open backing file: %s",
|
| 1134 |
error_get_pretty(local_err)); |
| 1135 |
error_free(local_err); |
| 1136 |
return ret;
|
| 1137 |
} |
| 1138 |
|
| 1139 |
if (bs->backing_hd->file) {
|
| 1140 |
pstrcpy(bs->backing_file, sizeof(bs->backing_file),
|
| 1141 |
bs->backing_hd->file->filename); |
| 1142 |
} |
| 1143 |
|
| 1144 |
/* Recalculate the BlockLimits with the backing file */
|
| 1145 |
bdrv_refresh_limits(bs); |
| 1146 |
|
| 1147 |
return 0; |
| 1148 |
} |
| 1149 |
|
| 1150 |
/*
|
| 1151 |
* Opens a disk image whose options are given as BlockdevRef in another block
|
| 1152 |
* device's options.
|
| 1153 |
*
|
| 1154 |
* If force_raw is true, bdrv_file_open() will be used, thereby preventing any
|
| 1155 |
* image format auto-detection. If it is false and a filename is given,
|
| 1156 |
* bdrv_open() will be used for auto-detection.
|
| 1157 |
*
|
| 1158 |
* If allow_none is true, no image will be opened if filename is false and no
|
| 1159 |
* BlockdevRef is given. *pbs will remain unchanged and 0 will be returned.
|
| 1160 |
*
|
| 1161 |
* bdrev_key specifies the key for the image's BlockdevRef in the options QDict.
|
| 1162 |
* That QDict has to be flattened; therefore, if the BlockdevRef is a QDict
|
| 1163 |
* itself, all options starting with "${bdref_key}." are considered part of the
|
| 1164 |
* BlockdevRef.
|
| 1165 |
*
|
| 1166 |
* The BlockdevRef will be removed from the options QDict.
|
| 1167 |
*
|
| 1168 |
* To conform with the behavior of bdrv_open(), *pbs has to be NULL.
|
| 1169 |
*/
|
| 1170 |
int bdrv_open_image(BlockDriverState **pbs, const char *filename, |
| 1171 |
QDict *options, const char *bdref_key, int flags, |
| 1172 |
bool force_raw, bool allow_none, Error **errp) |
| 1173 |
{
|
| 1174 |
QDict *image_options; |
| 1175 |
int ret;
|
| 1176 |
char *bdref_key_dot;
|
| 1177 |
const char *reference; |
| 1178 |
|
| 1179 |
assert(pbs); |
| 1180 |
assert(*pbs == NULL);
|
| 1181 |
|
| 1182 |
bdref_key_dot = g_strdup_printf("%s.", bdref_key);
|
| 1183 |
qdict_extract_subqdict(options, &image_options, bdref_key_dot); |
| 1184 |
g_free(bdref_key_dot); |
| 1185 |
|
| 1186 |
reference = qdict_get_try_str(options, bdref_key); |
| 1187 |
if (!filename && !reference && !qdict_size(image_options)) {
|
| 1188 |
if (allow_none) {
|
| 1189 |
ret = 0;
|
| 1190 |
} else {
|
| 1191 |
error_setg(errp, "A block device must be specified for \"%s\"",
|
| 1192 |
bdref_key); |
| 1193 |
ret = -EINVAL; |
| 1194 |
} |
| 1195 |
goto done;
|
| 1196 |
} |
| 1197 |
|
| 1198 |
if (filename && !force_raw) {
|
| 1199 |
/* If a filename is given and the block driver should be detected
|
| 1200 |
automatically (instead of using none), use bdrv_open() in order to do
|
| 1201 |
that auto-detection. */
|
| 1202 |
if (reference) {
|
| 1203 |
error_setg(errp, "Cannot reference an existing block device while "
|
| 1204 |
"giving a filename");
|
| 1205 |
ret = -EINVAL; |
| 1206 |
goto done;
|
| 1207 |
} |
| 1208 |
|
| 1209 |
ret = bdrv_open(pbs, filename, image_options, flags, NULL, errp);
|
| 1210 |
} else {
|
| 1211 |
ret = bdrv_file_open(pbs, filename, reference, image_options, flags, |
| 1212 |
errp); |
| 1213 |
} |
| 1214 |
|
| 1215 |
done:
|
| 1216 |
qdict_del(options, bdref_key); |
| 1217 |
return ret;
|
| 1218 |
} |
| 1219 |
|
| 1220 |
/*
|
| 1221 |
* Opens a disk image (raw, qcow2, vmdk, ...)
|
| 1222 |
*
|
| 1223 |
* options is a QDict of options to pass to the block drivers, or NULL for an
|
| 1224 |
* empty set of options. The reference to the QDict belongs to the block layer
|
| 1225 |
* after the call (even on failure), so if the caller intends to reuse the
|
| 1226 |
* dictionary, it needs to use QINCREF() before calling bdrv_open.
|
| 1227 |
*
|
| 1228 |
* If *pbs is NULL, a new BDS will be created with a pointer to it stored there.
|
| 1229 |
* If it is not NULL, the referenced BDS will be reused.
|
| 1230 |
*/
|
| 1231 |
int bdrv_open(BlockDriverState **pbs, const char *filename, QDict *options, |
| 1232 |
int flags, BlockDriver *drv, Error **errp)
|
| 1233 |
{
|
| 1234 |
int ret;
|
| 1235 |
/* TODO: extra byte is a hack to ensure MAX_PATH space on Windows. */
|
| 1236 |
char tmp_filename[PATH_MAX + 1]; |
| 1237 |
BlockDriverState *file = NULL, *bs;
|
| 1238 |
const char *drvname; |
| 1239 |
Error *local_err = NULL;
|
| 1240 |
|
| 1241 |
assert(pbs); |
| 1242 |
|
| 1243 |
if (*pbs) {
|
| 1244 |
bs = *pbs; |
| 1245 |
} else {
|
| 1246 |
bs = bdrv_new("");
|
| 1247 |
} |
| 1248 |
|
| 1249 |
/* NULL means an empty set of options */
|
| 1250 |
if (options == NULL) { |
| 1251 |
options = qdict_new(); |
| 1252 |
} |
| 1253 |
|
| 1254 |
bs->options = options; |
| 1255 |
options = qdict_clone_shallow(options); |
| 1256 |
|
| 1257 |
/* For snapshot=on, create a temporary qcow2 overlay */
|
| 1258 |
if (flags & BDRV_O_SNAPSHOT) {
|
| 1259 |
BlockDriverState *bs1; |
| 1260 |
int64_t total_size; |
| 1261 |
BlockDriver *bdrv_qcow2; |
| 1262 |
QEMUOptionParameter *create_options; |
| 1263 |
QDict *snapshot_options; |
| 1264 |
|
| 1265 |
/* if snapshot, we create a temporary backing file and open it
|
| 1266 |
instead of opening 'filename' directly */
|
| 1267 |
|
| 1268 |
/* Get the required size from the image */
|
| 1269 |
QINCREF(options); |
| 1270 |
bs1 = NULL;
|
| 1271 |
ret = bdrv_open(&bs1, filename, options, BDRV_O_NO_BACKING, |
| 1272 |
drv, &local_err); |
| 1273 |
if (ret < 0) { |
| 1274 |
goto fail;
|
| 1275 |
} |
| 1276 |
total_size = bdrv_getlength(bs1) & BDRV_SECTOR_MASK; |
| 1277 |
|
| 1278 |
bdrv_unref(bs1); |
| 1279 |
|
| 1280 |
/* Create the temporary image */
|
| 1281 |
ret = get_tmp_filename(tmp_filename, sizeof(tmp_filename));
|
| 1282 |
if (ret < 0) { |
| 1283 |
error_setg_errno(errp, -ret, "Could not get temporary filename");
|
| 1284 |
goto fail;
|
| 1285 |
} |
| 1286 |
|
| 1287 |
bdrv_qcow2 = bdrv_find_format("qcow2");
|
| 1288 |
create_options = parse_option_parameters("", bdrv_qcow2->create_options,
|
| 1289 |
NULL);
|
| 1290 |
|
| 1291 |
set_option_parameter_int(create_options, BLOCK_OPT_SIZE, total_size); |
| 1292 |
|
| 1293 |
ret = bdrv_create(bdrv_qcow2, tmp_filename, create_options, &local_err); |
| 1294 |
free_option_parameters(create_options); |
| 1295 |
if (ret < 0) { |
| 1296 |
error_setg_errno(errp, -ret, "Could not create temporary overlay "
|
| 1297 |
"'%s': %s", tmp_filename,
|
| 1298 |
error_get_pretty(local_err)); |
| 1299 |
error_free(local_err); |
| 1300 |
local_err = NULL;
|
| 1301 |
goto fail;
|
| 1302 |
} |
| 1303 |
|
| 1304 |
/* Prepare a new options QDict for the temporary file, where user
|
| 1305 |
* options refer to the backing file */
|
| 1306 |
if (filename) {
|
| 1307 |
qdict_put(options, "file.filename", qstring_from_str(filename));
|
| 1308 |
} |
| 1309 |
if (drv) {
|
| 1310 |
qdict_put(options, "driver", qstring_from_str(drv->format_name));
|
| 1311 |
} |
| 1312 |
|
| 1313 |
snapshot_options = qdict_new(); |
| 1314 |
qdict_put(snapshot_options, "backing", options);
|
| 1315 |
qdict_flatten(snapshot_options); |
| 1316 |
|
| 1317 |
bs->options = snapshot_options; |
| 1318 |
options = qdict_clone_shallow(bs->options); |
| 1319 |
|
| 1320 |
filename = tmp_filename; |
| 1321 |
drv = bdrv_qcow2; |
| 1322 |
bs->is_temporary = 1;
|
| 1323 |
} |
| 1324 |
|
| 1325 |
/* Open image file without format layer */
|
| 1326 |
if (flags & BDRV_O_RDWR) {
|
| 1327 |
flags |= BDRV_O_ALLOW_RDWR; |
| 1328 |
} |
| 1329 |
|
| 1330 |
assert(file == NULL);
|
| 1331 |
ret = bdrv_open_image(&file, filename, options, "file",
|
| 1332 |
bdrv_open_flags(bs, flags | BDRV_O_UNMAP), true, true, |
| 1333 |
&local_err); |
| 1334 |
if (ret < 0) { |
| 1335 |
goto fail;
|
| 1336 |
} |
| 1337 |
|
| 1338 |
/* Find the right image format driver */
|
| 1339 |
drvname = qdict_get_try_str(options, "driver");
|
| 1340 |
if (drvname) {
|
| 1341 |
drv = bdrv_find_format(drvname); |
| 1342 |
qdict_del(options, "driver");
|
| 1343 |
if (!drv) {
|
| 1344 |
error_setg(errp, "Invalid driver: '%s'", drvname);
|
| 1345 |
ret = -EINVAL; |
| 1346 |
goto unlink_and_fail;
|
| 1347 |
} |
| 1348 |
} |
| 1349 |
|
| 1350 |
if (!drv) {
|
| 1351 |
if (file) {
|
| 1352 |
ret = find_image_format(file, filename, &drv, &local_err); |
| 1353 |
} else {
|
| 1354 |
error_setg(errp, "Must specify either driver or file");
|
| 1355 |
ret = -EINVAL; |
| 1356 |
goto unlink_and_fail;
|
| 1357 |
} |
| 1358 |
} |
| 1359 |
|
| 1360 |
if (!drv) {
|
| 1361 |
goto unlink_and_fail;
|
| 1362 |
} |
| 1363 |
|
| 1364 |
/* Open the image */
|
| 1365 |
ret = bdrv_open_common(bs, file, options, flags, drv, &local_err); |
| 1366 |
if (ret < 0) { |
| 1367 |
goto unlink_and_fail;
|
| 1368 |
} |
| 1369 |
|
| 1370 |
if (file && (bs->file != file)) {
|
| 1371 |
bdrv_unref(file); |
| 1372 |
file = NULL;
|
| 1373 |
} |
| 1374 |
|
| 1375 |
/* If there is a backing file, use it */
|
| 1376 |
if ((flags & BDRV_O_NO_BACKING) == 0) { |
| 1377 |
QDict *backing_options; |
| 1378 |
|
| 1379 |
qdict_extract_subqdict(options, &backing_options, "backing.");
|
| 1380 |
ret = bdrv_open_backing_file(bs, backing_options, &local_err); |
| 1381 |
if (ret < 0) { |
| 1382 |
goto close_and_fail;
|
| 1383 |
} |
| 1384 |
} |
| 1385 |
|
| 1386 |
/* Check if any unknown options were used */
|
| 1387 |
if (qdict_size(options) != 0) { |
| 1388 |
const QDictEntry *entry = qdict_first(options);
|
| 1389 |
error_setg(errp, "Block format '%s' used by device '%s' doesn't "
|
| 1390 |
"support the option '%s'", drv->format_name, bs->device_name,
|
| 1391 |
entry->key); |
| 1392 |
|
| 1393 |
ret = -EINVAL; |
| 1394 |
goto close_and_fail;
|
| 1395 |
} |
| 1396 |
QDECREF(options); |
| 1397 |
|
| 1398 |
if (!bdrv_key_required(bs)) {
|
| 1399 |
bdrv_dev_change_media_cb(bs, true);
|
| 1400 |
} |
| 1401 |
|
| 1402 |
*pbs = bs; |
| 1403 |
return 0; |
| 1404 |
|
| 1405 |
unlink_and_fail:
|
| 1406 |
if (file != NULL) { |
| 1407 |
bdrv_unref(file); |
| 1408 |
} |
| 1409 |
if (bs->is_temporary) {
|
| 1410 |
unlink(filename); |
| 1411 |
} |
| 1412 |
fail:
|
| 1413 |
QDECREF(bs->options); |
| 1414 |
QDECREF(options); |
| 1415 |
bs->options = NULL;
|
| 1416 |
if (!*pbs) {
|
| 1417 |
/* If *pbs is NULL, a new BDS has been created in this function and
|
| 1418 |
needs to be freed now. Otherwise, it does not need to be closed,
|
| 1419 |
since it has not really been opened yet. */
|
| 1420 |
bdrv_unref(bs); |
| 1421 |
} |
| 1422 |
if (local_err) {
|
| 1423 |
error_propagate(errp, local_err); |
| 1424 |
} |
| 1425 |
return ret;
|
| 1426 |
|
| 1427 |
close_and_fail:
|
| 1428 |
/* See fail path, but now the BDS has to be always closed */
|
| 1429 |
if (*pbs) {
|
| 1430 |
bdrv_close(bs); |
| 1431 |
} else {
|
| 1432 |
bdrv_unref(bs); |
| 1433 |
} |
| 1434 |
QDECREF(options); |
| 1435 |
if (local_err) {
|
| 1436 |
error_propagate(errp, local_err); |
| 1437 |
} |
| 1438 |
return ret;
|
| 1439 |
} |
| 1440 |
|
| 1441 |
typedef struct BlockReopenQueueEntry { |
| 1442 |
bool prepared;
|
| 1443 |
BDRVReopenState state; |
| 1444 |
QSIMPLEQ_ENTRY(BlockReopenQueueEntry) entry; |
| 1445 |
} BlockReopenQueueEntry; |
| 1446 |
|
| 1447 |
/*
|
| 1448 |
* Adds a BlockDriverState to a simple queue for an atomic, transactional
|
| 1449 |
* reopen of multiple devices.
|
| 1450 |
*
|
| 1451 |
* bs_queue can either be an existing BlockReopenQueue that has had QSIMPLE_INIT
|
| 1452 |
* already performed, or alternatively may be NULL a new BlockReopenQueue will
|
| 1453 |
* be created and initialized. This newly created BlockReopenQueue should be
|
| 1454 |
* passed back in for subsequent calls that are intended to be of the same
|
| 1455 |
* atomic 'set'.
|
| 1456 |
*
|
| 1457 |
* bs is the BlockDriverState to add to the reopen queue.
|
| 1458 |
*
|
| 1459 |
* flags contains the open flags for the associated bs
|
| 1460 |
*
|
| 1461 |
* returns a pointer to bs_queue, which is either the newly allocated
|
| 1462 |
* bs_queue, or the existing bs_queue being used.
|
| 1463 |
*
|
| 1464 |
*/
|
| 1465 |
BlockReopenQueue *bdrv_reopen_queue(BlockReopenQueue *bs_queue, |
| 1466 |
BlockDriverState *bs, int flags)
|
| 1467 |
{
|
| 1468 |
assert(bs != NULL);
|
| 1469 |
|
| 1470 |
BlockReopenQueueEntry *bs_entry; |
| 1471 |
if (bs_queue == NULL) { |
| 1472 |
bs_queue = g_new0(BlockReopenQueue, 1);
|
| 1473 |
QSIMPLEQ_INIT(bs_queue); |
| 1474 |
} |
| 1475 |
|
| 1476 |
if (bs->file) {
|
| 1477 |
bdrv_reopen_queue(bs_queue, bs->file, flags); |
| 1478 |
} |
| 1479 |
|
| 1480 |
bs_entry = g_new0(BlockReopenQueueEntry, 1);
|
| 1481 |
QSIMPLEQ_INSERT_TAIL(bs_queue, bs_entry, entry); |
| 1482 |
|
| 1483 |
bs_entry->state.bs = bs; |
| 1484 |
bs_entry->state.flags = flags; |
| 1485 |
|
| 1486 |
return bs_queue;
|
| 1487 |
} |
| 1488 |
|
| 1489 |
/*
|
| 1490 |
* Reopen multiple BlockDriverStates atomically & transactionally.
|
| 1491 |
*
|
| 1492 |
* The queue passed in (bs_queue) must have been built up previous
|
| 1493 |
* via bdrv_reopen_queue().
|
| 1494 |
*
|
| 1495 |
* Reopens all BDS specified in the queue, with the appropriate
|
| 1496 |
* flags. All devices are prepared for reopen, and failure of any
|
| 1497 |
* device will cause all device changes to be abandonded, and intermediate
|
| 1498 |
* data cleaned up.
|
| 1499 |
*
|
| 1500 |
* If all devices prepare successfully, then the changes are committed
|
| 1501 |
* to all devices.
|
| 1502 |
*
|
| 1503 |
*/
|
| 1504 |
int bdrv_reopen_multiple(BlockReopenQueue *bs_queue, Error **errp)
|
| 1505 |
{
|
| 1506 |
int ret = -1; |
| 1507 |
BlockReopenQueueEntry *bs_entry, *next; |
| 1508 |
Error *local_err = NULL;
|
| 1509 |
|
| 1510 |
assert(bs_queue != NULL);
|
| 1511 |
|
| 1512 |
bdrv_drain_all(); |
| 1513 |
|
| 1514 |
QSIMPLEQ_FOREACH(bs_entry, bs_queue, entry) {
|
| 1515 |
if (bdrv_reopen_prepare(&bs_entry->state, bs_queue, &local_err)) {
|
| 1516 |
error_propagate(errp, local_err); |
| 1517 |
goto cleanup;
|
| 1518 |
} |
| 1519 |
bs_entry->prepared = true;
|
| 1520 |
} |
| 1521 |
|
| 1522 |
/* If we reach this point, we have success and just need to apply the
|
| 1523 |
* changes
|
| 1524 |
*/
|
| 1525 |
QSIMPLEQ_FOREACH(bs_entry, bs_queue, entry) {
|
| 1526 |
bdrv_reopen_commit(&bs_entry->state); |
| 1527 |
} |
| 1528 |
|
| 1529 |
ret = 0;
|
| 1530 |
|
| 1531 |
cleanup:
|
| 1532 |
QSIMPLEQ_FOREACH_SAFE(bs_entry, bs_queue, entry, next) {
|
| 1533 |
if (ret && bs_entry->prepared) {
|
| 1534 |
bdrv_reopen_abort(&bs_entry->state); |
| 1535 |
} |
| 1536 |
g_free(bs_entry); |
| 1537 |
} |
| 1538 |
g_free(bs_queue); |
| 1539 |
return ret;
|
| 1540 |
} |
| 1541 |
|
| 1542 |
|
| 1543 |
/* Reopen a single BlockDriverState with the specified flags. */
|
| 1544 |
int bdrv_reopen(BlockDriverState *bs, int bdrv_flags, Error **errp) |
| 1545 |
{
|
| 1546 |
int ret = -1; |
| 1547 |
Error *local_err = NULL;
|
| 1548 |
BlockReopenQueue *queue = bdrv_reopen_queue(NULL, bs, bdrv_flags);
|
| 1549 |
|
| 1550 |
ret = bdrv_reopen_multiple(queue, &local_err); |
| 1551 |
if (local_err != NULL) { |
| 1552 |
error_propagate(errp, local_err); |
| 1553 |
} |
| 1554 |
return ret;
|
| 1555 |
} |
| 1556 |
|
| 1557 |
|
| 1558 |
/*
|
| 1559 |
* Prepares a BlockDriverState for reopen. All changes are staged in the
|
| 1560 |
* 'opaque' field of the BDRVReopenState, which is used and allocated by
|
| 1561 |
* the block driver layer .bdrv_reopen_prepare()
|
| 1562 |
*
|
| 1563 |
* bs is the BlockDriverState to reopen
|
| 1564 |
* flags are the new open flags
|
| 1565 |
* queue is the reopen queue
|
| 1566 |
*
|
| 1567 |
* Returns 0 on success, non-zero on error. On error errp will be set
|
| 1568 |
* as well.
|
| 1569 |
*
|
| 1570 |
* On failure, bdrv_reopen_abort() will be called to clean up any data.
|
| 1571 |
* It is the responsibility of the caller to then call the abort() or
|
| 1572 |
* commit() for any other BDS that have been left in a prepare() state
|
| 1573 |
*
|
| 1574 |
*/
|
| 1575 |
int bdrv_reopen_prepare(BDRVReopenState *reopen_state, BlockReopenQueue *queue,
|
| 1576 |
Error **errp) |
| 1577 |
{
|
| 1578 |
int ret = -1; |
| 1579 |
Error *local_err = NULL;
|
| 1580 |
BlockDriver *drv; |
| 1581 |
|
| 1582 |
assert(reopen_state != NULL);
|
| 1583 |
assert(reopen_state->bs->drv != NULL);
|
| 1584 |
drv = reopen_state->bs->drv; |
| 1585 |
|
| 1586 |
/* if we are to stay read-only, do not allow permission change
|
| 1587 |
* to r/w */
|
| 1588 |
if (!(reopen_state->bs->open_flags & BDRV_O_ALLOW_RDWR) &&
|
| 1589 |
reopen_state->flags & BDRV_O_RDWR) {
|
| 1590 |
error_set(errp, QERR_DEVICE_IS_READ_ONLY, |
| 1591 |
reopen_state->bs->device_name); |
| 1592 |
goto error;
|
| 1593 |
} |
| 1594 |
|
| 1595 |
|
| 1596 |
ret = bdrv_flush(reopen_state->bs); |
| 1597 |
if (ret) {
|
| 1598 |
error_set(errp, ERROR_CLASS_GENERIC_ERROR, "Error (%s) flushing drive",
|
| 1599 |
strerror(-ret)); |
| 1600 |
goto error;
|
| 1601 |
} |
| 1602 |
|
| 1603 |
if (drv->bdrv_reopen_prepare) {
|
| 1604 |
ret = drv->bdrv_reopen_prepare(reopen_state, queue, &local_err); |
| 1605 |
if (ret) {
|
| 1606 |
if (local_err != NULL) { |
| 1607 |
error_propagate(errp, local_err); |
| 1608 |
} else {
|
| 1609 |
error_setg(errp, "failed while preparing to reopen image '%s'",
|
| 1610 |
reopen_state->bs->filename); |
| 1611 |
} |
| 1612 |
goto error;
|
| 1613 |
} |
| 1614 |
} else {
|
| 1615 |
/* It is currently mandatory to have a bdrv_reopen_prepare()
|
| 1616 |
* handler for each supported drv. */
|
| 1617 |
error_set(errp, QERR_BLOCK_FORMAT_FEATURE_NOT_SUPPORTED, |
| 1618 |
drv->format_name, reopen_state->bs->device_name, |
| 1619 |
"reopening of file");
|
| 1620 |
ret = -1;
|
| 1621 |
goto error;
|
| 1622 |
} |
| 1623 |
|
| 1624 |
ret = 0;
|
| 1625 |
|
| 1626 |
error:
|
| 1627 |
return ret;
|
| 1628 |
} |
| 1629 |
|
| 1630 |
/*
|
| 1631 |
* Takes the staged changes for the reopen from bdrv_reopen_prepare(), and
|
| 1632 |
* makes them final by swapping the staging BlockDriverState contents into
|
| 1633 |
* the active BlockDriverState contents.
|
| 1634 |
*/
|
| 1635 |
void bdrv_reopen_commit(BDRVReopenState *reopen_state)
|
| 1636 |
{
|
| 1637 |
BlockDriver *drv; |
| 1638 |
|
| 1639 |
assert(reopen_state != NULL);
|
| 1640 |
drv = reopen_state->bs->drv; |
| 1641 |
assert(drv != NULL);
|
| 1642 |
|
| 1643 |
/* If there are any driver level actions to take */
|
| 1644 |
if (drv->bdrv_reopen_commit) {
|
| 1645 |
drv->bdrv_reopen_commit(reopen_state); |
| 1646 |
} |
| 1647 |
|
| 1648 |
/* set BDS specific flags now */
|
| 1649 |
reopen_state->bs->open_flags = reopen_state->flags; |
| 1650 |
reopen_state->bs->enable_write_cache = !!(reopen_state->flags & |
| 1651 |
BDRV_O_CACHE_WB); |
| 1652 |
reopen_state->bs->read_only = !(reopen_state->flags & BDRV_O_RDWR); |
| 1653 |
|
| 1654 |
bdrv_refresh_limits(reopen_state->bs); |
| 1655 |
} |
| 1656 |
|
| 1657 |
/*
|
| 1658 |
* Abort the reopen, and delete and free the staged changes in
|
| 1659 |
* reopen_state
|
| 1660 |
*/
|
| 1661 |
void bdrv_reopen_abort(BDRVReopenState *reopen_state)
|
| 1662 |
{
|
| 1663 |
BlockDriver *drv; |
| 1664 |
|
| 1665 |
assert(reopen_state != NULL);
|
| 1666 |
drv = reopen_state->bs->drv; |
| 1667 |
assert(drv != NULL);
|
| 1668 |
|
| 1669 |
if (drv->bdrv_reopen_abort) {
|
| 1670 |
drv->bdrv_reopen_abort(reopen_state); |
| 1671 |
} |
| 1672 |
} |
| 1673 |
|
| 1674 |
|
| 1675 |
void bdrv_close(BlockDriverState *bs)
|
| 1676 |
{
|
| 1677 |
if (bs->job) {
|
| 1678 |
block_job_cancel_sync(bs->job); |
| 1679 |
} |
| 1680 |
bdrv_drain_all(); /* complete I/O */
|
| 1681 |
bdrv_flush(bs); |
| 1682 |
bdrv_drain_all(); /* in case flush left pending I/O */
|
| 1683 |
notifier_list_notify(&bs->close_notifiers, bs); |
| 1684 |
|
| 1685 |
if (bs->drv) {
|
| 1686 |
if (bs->backing_hd) {
|
| 1687 |
bdrv_unref(bs->backing_hd); |
| 1688 |
bs->backing_hd = NULL;
|
| 1689 |
} |
| 1690 |
bs->drv->bdrv_close(bs); |
| 1691 |
g_free(bs->opaque); |
| 1692 |
#ifdef _WIN32
|
| 1693 |
if (bs->is_temporary) {
|
| 1694 |
unlink(bs->filename); |
| 1695 |
} |
| 1696 |
#endif
|
| 1697 |
bs->opaque = NULL;
|
| 1698 |
bs->drv = NULL;
|
| 1699 |
bs->copy_on_read = 0;
|
| 1700 |
bs->backing_file[0] = '\0'; |
| 1701 |
bs->backing_format[0] = '\0'; |
| 1702 |
bs->total_sectors = 0;
|
| 1703 |
bs->encrypted = 0;
|
| 1704 |
bs->valid_key = 0;
|
| 1705 |
bs->sg = 0;
|
| 1706 |
bs->growable = 0;
|
| 1707 |
bs->zero_beyond_eof = false;
|
| 1708 |
QDECREF(bs->options); |
| 1709 |
bs->options = NULL;
|
| 1710 |
|
| 1711 |
if (bs->file != NULL) { |
| 1712 |
bdrv_unref(bs->file); |
| 1713 |
bs->file = NULL;
|
| 1714 |
} |
| 1715 |
} |
| 1716 |
|
| 1717 |
bdrv_dev_change_media_cb(bs, false);
|
| 1718 |
|
| 1719 |
/*throttling disk I/O limits*/
|
| 1720 |
if (bs->io_limits_enabled) {
|
| 1721 |
bdrv_io_limits_disable(bs); |
| 1722 |
} |
| 1723 |
} |
| 1724 |
|
| 1725 |
void bdrv_close_all(void) |
| 1726 |
{
|
| 1727 |
BlockDriverState *bs; |
| 1728 |
|
| 1729 |
QTAILQ_FOREACH(bs, &bdrv_states, device_list) {
|
| 1730 |
bdrv_close(bs); |
| 1731 |
} |
| 1732 |
} |
| 1733 |
|
| 1734 |
/* Check if any requests are in-flight (including throttled requests) */
|
| 1735 |
static bool bdrv_requests_pending(BlockDriverState *bs) |
| 1736 |
{
|
| 1737 |
if (!QLIST_EMPTY(&bs->tracked_requests)) {
|
| 1738 |
return true; |
| 1739 |
} |
| 1740 |
if (!qemu_co_queue_empty(&bs->throttled_reqs[0])) { |
| 1741 |
return true; |
| 1742 |
} |
| 1743 |
if (!qemu_co_queue_empty(&bs->throttled_reqs[1])) { |
| 1744 |
return true; |
| 1745 |
} |
| 1746 |
if (bs->file && bdrv_requests_pending(bs->file)) {
|
| 1747 |
return true; |
| 1748 |
} |
| 1749 |
if (bs->backing_hd && bdrv_requests_pending(bs->backing_hd)) {
|
| 1750 |
return true; |
| 1751 |
} |
| 1752 |
return false; |
| 1753 |
} |
| 1754 |
|
| 1755 |
static bool bdrv_requests_pending_all(void) |
| 1756 |
{
|
| 1757 |
BlockDriverState *bs; |
| 1758 |
QTAILQ_FOREACH(bs, &bdrv_states, device_list) {
|
| 1759 |
if (bdrv_requests_pending(bs)) {
|
| 1760 |
return true; |
| 1761 |
} |
| 1762 |
} |
| 1763 |
return false; |
| 1764 |
} |
| 1765 |
|
| 1766 |
/*
|
| 1767 |
* Wait for pending requests to complete across all BlockDriverStates
|
| 1768 |
*
|
| 1769 |
* This function does not flush data to disk, use bdrv_flush_all() for that
|
| 1770 |
* after calling this function.
|
| 1771 |
*
|
| 1772 |
* Note that completion of an asynchronous I/O operation can trigger any
|
| 1773 |
* number of other I/O operations on other devices---for example a coroutine
|
| 1774 |
* can be arbitrarily complex and a constant flow of I/O can come until the
|
| 1775 |
* coroutine is complete. Because of this, it is not possible to have a
|
| 1776 |
* function to drain a single device's I/O queue.
|
| 1777 |
*/
|
| 1778 |
void bdrv_drain_all(void) |
| 1779 |
{
|
| 1780 |
/* Always run first iteration so any pending completion BHs run */
|
| 1781 |
bool busy = true; |
| 1782 |
BlockDriverState *bs; |
| 1783 |
|
| 1784 |
while (busy) {
|
| 1785 |
QTAILQ_FOREACH(bs, &bdrv_states, device_list) {
|
| 1786 |
bdrv_start_throttled_reqs(bs); |
| 1787 |
} |
| 1788 |
|
| 1789 |
busy = bdrv_requests_pending_all(); |
| 1790 |
busy |= aio_poll(qemu_get_aio_context(), busy); |
| 1791 |
} |
| 1792 |
} |
| 1793 |
|
| 1794 |
/* make a BlockDriverState anonymous by removing from bdrv_state and
|
| 1795 |
* graph_bdrv_state list.
|
| 1796 |
Also, NULL terminate the device_name to prevent double remove */
|
| 1797 |
void bdrv_make_anon(BlockDriverState *bs)
|
| 1798 |
{
|
| 1799 |
if (bs->device_name[0] != '\0') { |
| 1800 |
QTAILQ_REMOVE(&bdrv_states, bs, device_list); |
| 1801 |
} |
| 1802 |
bs->device_name[0] = '\0'; |
| 1803 |
if (bs->node_name[0] != '\0') { |
| 1804 |
QTAILQ_REMOVE(&graph_bdrv_states, bs, node_list); |
| 1805 |
} |
| 1806 |
bs->node_name[0] = '\0'; |
| 1807 |
} |
| 1808 |
|
| 1809 |
static void bdrv_rebind(BlockDriverState *bs) |
| 1810 |
{
|
| 1811 |
if (bs->drv && bs->drv->bdrv_rebind) {
|
| 1812 |
bs->drv->bdrv_rebind(bs); |
| 1813 |
} |
| 1814 |
} |
| 1815 |
|
| 1816 |
static void bdrv_move_feature_fields(BlockDriverState *bs_dest, |
| 1817 |
BlockDriverState *bs_src) |
| 1818 |
{
|
| 1819 |
/* move some fields that need to stay attached to the device */
|
| 1820 |
bs_dest->open_flags = bs_src->open_flags; |
| 1821 |
|
| 1822 |
/* dev info */
|
| 1823 |
bs_dest->dev_ops = bs_src->dev_ops; |
| 1824 |
bs_dest->dev_opaque = bs_src->dev_opaque; |
| 1825 |
bs_dest->dev = bs_src->dev; |
| 1826 |
bs_dest->guest_block_size = bs_src->guest_block_size; |
| 1827 |
bs_dest->copy_on_read = bs_src->copy_on_read; |
| 1828 |
|
| 1829 |
bs_dest->enable_write_cache = bs_src->enable_write_cache; |
| 1830 |
|
| 1831 |
/* i/o throttled req */
|
| 1832 |
memcpy(&bs_dest->throttle_state, |
| 1833 |
&bs_src->throttle_state, |
| 1834 |
sizeof(ThrottleState));
|
| 1835 |
bs_dest->throttled_reqs[0] = bs_src->throttled_reqs[0]; |
| 1836 |
bs_dest->throttled_reqs[1] = bs_src->throttled_reqs[1]; |
| 1837 |
bs_dest->io_limits_enabled = bs_src->io_limits_enabled; |
| 1838 |
|
| 1839 |
/* r/w error */
|
| 1840 |
bs_dest->on_read_error = bs_src->on_read_error; |
| 1841 |
bs_dest->on_write_error = bs_src->on_write_error; |
| 1842 |
|
| 1843 |
/* i/o status */
|
| 1844 |
bs_dest->iostatus_enabled = bs_src->iostatus_enabled; |
| 1845 |
bs_dest->iostatus = bs_src->iostatus; |
| 1846 |
|
| 1847 |
/* dirty bitmap */
|
| 1848 |
bs_dest->dirty_bitmaps = bs_src->dirty_bitmaps; |
| 1849 |
|
| 1850 |
/* reference count */
|
| 1851 |
bs_dest->refcnt = bs_src->refcnt; |
| 1852 |
|
| 1853 |
/* job */
|
| 1854 |
bs_dest->in_use = bs_src->in_use; |
| 1855 |
bs_dest->job = bs_src->job; |
| 1856 |
|
| 1857 |
/* keep the same entry in bdrv_states */
|
| 1858 |
pstrcpy(bs_dest->device_name, sizeof(bs_dest->device_name),
|
| 1859 |
bs_src->device_name); |
| 1860 |
bs_dest->device_list = bs_src->device_list; |
| 1861 |
|
| 1862 |
/* keep the same entry in graph_bdrv_states
|
| 1863 |
* We do want to swap name but don't want to swap linked list entries
|
| 1864 |
*/
|
| 1865 |
bs_dest->node_list = bs_src->node_list; |
| 1866 |
} |
| 1867 |
|
| 1868 |
/*
|
| 1869 |
* Swap bs contents for two image chains while they are live,
|
| 1870 |
* while keeping required fields on the BlockDriverState that is
|
| 1871 |
* actually attached to a device.
|
| 1872 |
*
|
| 1873 |
* This will modify the BlockDriverState fields, and swap contents
|
| 1874 |
* between bs_new and bs_old. Both bs_new and bs_old are modified.
|
| 1875 |
*
|
| 1876 |
* bs_new is required to be anonymous.
|
| 1877 |
*
|
| 1878 |
* This function does not create any image files.
|
| 1879 |
*/
|
| 1880 |
void bdrv_swap(BlockDriverState *bs_new, BlockDriverState *bs_old)
|
| 1881 |
{
|
| 1882 |
BlockDriverState tmp; |
| 1883 |
|
| 1884 |
/* bs_new must be anonymous and shouldn't have anything fancy enabled */
|
| 1885 |
assert(bs_new->device_name[0] == '\0'); |
| 1886 |
assert(QLIST_EMPTY(&bs_new->dirty_bitmaps)); |
| 1887 |
assert(bs_new->job == NULL);
|
| 1888 |
assert(bs_new->dev == NULL);
|
| 1889 |
assert(bs_new->in_use == 0);
|
| 1890 |
assert(bs_new->io_limits_enabled == false);
|
| 1891 |
assert(!throttle_have_timer(&bs_new->throttle_state)); |
| 1892 |
|
| 1893 |
tmp = *bs_new; |
| 1894 |
*bs_new = *bs_old; |
| 1895 |
*bs_old = tmp; |
| 1896 |
|
| 1897 |
/* there are some fields that should not be swapped, move them back */
|
| 1898 |
bdrv_move_feature_fields(&tmp, bs_old); |
| 1899 |
bdrv_move_feature_fields(bs_old, bs_new); |
| 1900 |
bdrv_move_feature_fields(bs_new, &tmp); |
| 1901 |
|
| 1902 |
/* bs_new shouldn't be in bdrv_states even after the swap! */
|
| 1903 |
assert(bs_new->device_name[0] == '\0'); |
| 1904 |
|
| 1905 |
/* Check a few fields that should remain attached to the device */
|
| 1906 |
assert(bs_new->dev == NULL);
|
| 1907 |
assert(bs_new->job == NULL);
|
| 1908 |
assert(bs_new->in_use == 0);
|
| 1909 |
assert(bs_new->io_limits_enabled == false);
|
| 1910 |
assert(!throttle_have_timer(&bs_new->throttle_state)); |
| 1911 |
|
| 1912 |
bdrv_rebind(bs_new); |
| 1913 |
bdrv_rebind(bs_old); |
| 1914 |
} |
| 1915 |
|
| 1916 |
/*
|
| 1917 |
* Add new bs contents at the top of an image chain while the chain is
|
| 1918 |
* live, while keeping required fields on the top layer.
|
| 1919 |
*
|
| 1920 |
* This will modify the BlockDriverState fields, and swap contents
|
| 1921 |
* between bs_new and bs_top. Both bs_new and bs_top are modified.
|
| 1922 |
*
|
| 1923 |
* bs_new is required to be anonymous.
|
| 1924 |
*
|
| 1925 |
* This function does not create any image files.
|
| 1926 |
*/
|
| 1927 |
void bdrv_append(BlockDriverState *bs_new, BlockDriverState *bs_top)
|
| 1928 |
{
|
| 1929 |
bdrv_swap(bs_new, bs_top); |
| 1930 |
|
| 1931 |
/* The contents of 'tmp' will become bs_top, as we are
|
| 1932 |
* swapping bs_new and bs_top contents. */
|
| 1933 |
bs_top->backing_hd = bs_new; |
| 1934 |
bs_top->open_flags &= ~BDRV_O_NO_BACKING; |
| 1935 |
pstrcpy(bs_top->backing_file, sizeof(bs_top->backing_file),
|
| 1936 |
bs_new->filename); |
| 1937 |
pstrcpy(bs_top->backing_format, sizeof(bs_top->backing_format),
|
| 1938 |
bs_new->drv ? bs_new->drv->format_name : "");
|
| 1939 |
} |
| 1940 |
|
| 1941 |
static void bdrv_delete(BlockDriverState *bs) |
| 1942 |
{
|
| 1943 |
assert(!bs->dev); |
| 1944 |
assert(!bs->job); |
| 1945 |
assert(!bs->in_use); |
| 1946 |
assert(!bs->refcnt); |
| 1947 |
assert(QLIST_EMPTY(&bs->dirty_bitmaps)); |
| 1948 |
|
| 1949 |
bdrv_close(bs); |
| 1950 |
|
| 1951 |
/* remove from list, if necessary */
|
| 1952 |
bdrv_make_anon(bs); |
| 1953 |
|
| 1954 |
g_free(bs); |
| 1955 |
} |
| 1956 |
|
| 1957 |
int bdrv_attach_dev(BlockDriverState *bs, void *dev) |
| 1958 |
/* TODO change to DeviceState *dev when all users are qdevified */
|
| 1959 |
{
|
| 1960 |
if (bs->dev) {
|
| 1961 |
return -EBUSY;
|
| 1962 |
} |
| 1963 |
bs->dev = dev; |
| 1964 |
bdrv_iostatus_reset(bs); |
| 1965 |
return 0; |
| 1966 |
} |
| 1967 |
|
| 1968 |
/* TODO qdevified devices don't use this, remove when devices are qdevified */
|
| 1969 |
void bdrv_attach_dev_nofail(BlockDriverState *bs, void *dev) |
| 1970 |
{
|
| 1971 |
if (bdrv_attach_dev(bs, dev) < 0) { |
| 1972 |
abort(); |
| 1973 |
} |
| 1974 |
} |
| 1975 |
|
| 1976 |
void bdrv_detach_dev(BlockDriverState *bs, void *dev) |
| 1977 |
/* TODO change to DeviceState *dev when all users are qdevified */
|
| 1978 |
{
|
| 1979 |
assert(bs->dev == dev); |
| 1980 |
bs->dev = NULL;
|
| 1981 |
bs->dev_ops = NULL;
|
| 1982 |
bs->dev_opaque = NULL;
|
| 1983 |
bs->guest_block_size = 512;
|
| 1984 |
} |
| 1985 |
|
| 1986 |
/* TODO change to return DeviceState * when all users are qdevified */
|
| 1987 |
void *bdrv_get_attached_dev(BlockDriverState *bs)
|
| 1988 |
{
|
| 1989 |
return bs->dev;
|
| 1990 |
} |
| 1991 |
|
| 1992 |
void bdrv_set_dev_ops(BlockDriverState *bs, const BlockDevOps *ops, |
| 1993 |
void *opaque)
|
| 1994 |
{
|
| 1995 |
bs->dev_ops = ops; |
| 1996 |
bs->dev_opaque = opaque; |
| 1997 |
} |
| 1998 |
|
| 1999 |
void bdrv_emit_qmp_error_event(const BlockDriverState *bdrv, |
| 2000 |
enum MonitorEvent ev,
|
| 2001 |
BlockErrorAction action, bool is_read)
|
| 2002 |
{
|
| 2003 |
QObject *data; |
| 2004 |
const char *action_str; |
| 2005 |
|
| 2006 |
switch (action) {
|
| 2007 |
case BDRV_ACTION_REPORT:
|
| 2008 |
action_str = "report";
|
| 2009 |
break;
|
| 2010 |
case BDRV_ACTION_IGNORE:
|
| 2011 |
action_str = "ignore";
|
| 2012 |
break;
|
| 2013 |
case BDRV_ACTION_STOP:
|
| 2014 |
action_str = "stop";
|
| 2015 |
break;
|
| 2016 |
default:
|
| 2017 |
abort(); |
| 2018 |
} |
| 2019 |
|
| 2020 |
data = qobject_from_jsonf("{ 'device': %s, 'action': %s, 'operation': %s }",
|
| 2021 |
bdrv->device_name, |
| 2022 |
action_str, |
| 2023 |
is_read ? "read" : "write"); |
| 2024 |
monitor_protocol_event(ev, data); |
| 2025 |
|
| 2026 |
qobject_decref(data); |
| 2027 |
} |
| 2028 |
|
| 2029 |
static void bdrv_emit_qmp_eject_event(BlockDriverState *bs, bool ejected) |
| 2030 |
{
|
| 2031 |
QObject *data; |
| 2032 |
|
| 2033 |
data = qobject_from_jsonf("{ 'device': %s, 'tray-open': %i }",
|
| 2034 |
bdrv_get_device_name(bs), ejected); |
| 2035 |
monitor_protocol_event(QEVENT_DEVICE_TRAY_MOVED, data); |
| 2036 |
|
| 2037 |
qobject_decref(data); |
| 2038 |
} |
| 2039 |
|
| 2040 |
static void bdrv_dev_change_media_cb(BlockDriverState *bs, bool load) |
| 2041 |
{
|
| 2042 |
if (bs->dev_ops && bs->dev_ops->change_media_cb) {
|
| 2043 |
bool tray_was_closed = !bdrv_dev_is_tray_open(bs);
|
| 2044 |
bs->dev_ops->change_media_cb(bs->dev_opaque, load); |
| 2045 |
if (tray_was_closed) {
|
| 2046 |
/* tray open */
|
| 2047 |
bdrv_emit_qmp_eject_event(bs, true);
|
| 2048 |
} |
| 2049 |
if (load) {
|
| 2050 |
/* tray close */
|
| 2051 |
bdrv_emit_qmp_eject_event(bs, false);
|
| 2052 |
} |
| 2053 |
} |
| 2054 |
} |
| 2055 |
|
| 2056 |
bool bdrv_dev_has_removable_media(BlockDriverState *bs)
|
| 2057 |
{
|
| 2058 |
return !bs->dev || (bs->dev_ops && bs->dev_ops->change_media_cb);
|
| 2059 |
} |
| 2060 |
|
| 2061 |
void bdrv_dev_eject_request(BlockDriverState *bs, bool force) |
| 2062 |
{
|
| 2063 |
if (bs->dev_ops && bs->dev_ops->eject_request_cb) {
|
| 2064 |
bs->dev_ops->eject_request_cb(bs->dev_opaque, force); |
| 2065 |
} |
| 2066 |
} |
| 2067 |
|
| 2068 |
bool bdrv_dev_is_tray_open(BlockDriverState *bs)
|
| 2069 |
{
|
| 2070 |
if (bs->dev_ops && bs->dev_ops->is_tray_open) {
|
| 2071 |
return bs->dev_ops->is_tray_open(bs->dev_opaque);
|
| 2072 |
} |
| 2073 |
return false; |
| 2074 |
} |
| 2075 |
|
| 2076 |
static void bdrv_dev_resize_cb(BlockDriverState *bs) |
| 2077 |
{
|
| 2078 |
if (bs->dev_ops && bs->dev_ops->resize_cb) {
|
| 2079 |
bs->dev_ops->resize_cb(bs->dev_opaque); |
| 2080 |
} |
| 2081 |
} |
| 2082 |
|
| 2083 |
bool bdrv_dev_is_medium_locked(BlockDriverState *bs)
|
| 2084 |
{
|
| 2085 |
if (bs->dev_ops && bs->dev_ops->is_medium_locked) {
|
| 2086 |
return bs->dev_ops->is_medium_locked(bs->dev_opaque);
|
| 2087 |
} |
| 2088 |
return false; |
| 2089 |
} |
| 2090 |
|
| 2091 |
/*
|
| 2092 |
* Run consistency checks on an image
|
| 2093 |
*
|
| 2094 |
* Returns 0 if the check could be completed (it doesn't mean that the image is
|
| 2095 |
* free of errors) or -errno when an internal error occurred. The results of the
|
| 2096 |
* check are stored in res.
|
| 2097 |
*/
|
| 2098 |
int bdrv_check(BlockDriverState *bs, BdrvCheckResult *res, BdrvCheckMode fix)
|
| 2099 |
{
|
| 2100 |
if (bs->drv->bdrv_check == NULL) { |
| 2101 |
return -ENOTSUP;
|
| 2102 |
} |
| 2103 |
|
| 2104 |
memset(res, 0, sizeof(*res)); |
| 2105 |
return bs->drv->bdrv_check(bs, res, fix);
|
| 2106 |
} |
| 2107 |
|
| 2108 |
#define COMMIT_BUF_SECTORS 2048 |
| 2109 |
|
| 2110 |
/* commit COW file into the raw image */
|
| 2111 |
int bdrv_commit(BlockDriverState *bs)
|
| 2112 |
{
|
| 2113 |
BlockDriver *drv = bs->drv; |
| 2114 |
int64_t sector, total_sectors, length, backing_length; |
| 2115 |
int n, ro, open_flags;
|
| 2116 |
int ret = 0; |
| 2117 |
uint8_t *buf = NULL;
|
| 2118 |
char filename[PATH_MAX];
|
| 2119 |
|
| 2120 |
if (!drv)
|
| 2121 |
return -ENOMEDIUM;
|
| 2122 |
|
| 2123 |
if (!bs->backing_hd) {
|
| 2124 |
return -ENOTSUP;
|
| 2125 |
} |
| 2126 |
|
| 2127 |
if (bdrv_in_use(bs) || bdrv_in_use(bs->backing_hd)) {
|
| 2128 |
return -EBUSY;
|
| 2129 |
} |
| 2130 |
|
| 2131 |
ro = bs->backing_hd->read_only; |
| 2132 |
/* Use pstrcpy (not strncpy): filename must be NUL-terminated. */
|
| 2133 |
pstrcpy(filename, sizeof(filename), bs->backing_hd->filename);
|
| 2134 |
open_flags = bs->backing_hd->open_flags; |
| 2135 |
|
| 2136 |
if (ro) {
|
| 2137 |
if (bdrv_reopen(bs->backing_hd, open_flags | BDRV_O_RDWR, NULL)) { |
| 2138 |
return -EACCES;
|
| 2139 |
} |
| 2140 |
} |
| 2141 |
|
| 2142 |
length = bdrv_getlength(bs); |
| 2143 |
if (length < 0) { |
| 2144 |
ret = length; |
| 2145 |
goto ro_cleanup;
|
| 2146 |
} |
| 2147 |
|
| 2148 |
backing_length = bdrv_getlength(bs->backing_hd); |
| 2149 |
if (backing_length < 0) { |
| 2150 |
ret = backing_length; |
| 2151 |
goto ro_cleanup;
|
| 2152 |
} |
| 2153 |
|
| 2154 |
/* If our top snapshot is larger than the backing file image,
|
| 2155 |
* grow the backing file image if possible. If not possible,
|
| 2156 |
* we must return an error */
|
| 2157 |
if (length > backing_length) {
|
| 2158 |
ret = bdrv_truncate(bs->backing_hd, length); |
| 2159 |
if (ret < 0) { |
| 2160 |
goto ro_cleanup;
|
| 2161 |
} |
| 2162 |
} |
| 2163 |
|
| 2164 |
total_sectors = length >> BDRV_SECTOR_BITS; |
| 2165 |
buf = g_malloc(COMMIT_BUF_SECTORS * BDRV_SECTOR_SIZE); |
| 2166 |
|
| 2167 |
for (sector = 0; sector < total_sectors; sector += n) { |
| 2168 |
ret = bdrv_is_allocated(bs, sector, COMMIT_BUF_SECTORS, &n); |
| 2169 |
if (ret < 0) { |
| 2170 |
goto ro_cleanup;
|
| 2171 |
} |
| 2172 |
if (ret) {
|
| 2173 |
ret = bdrv_read(bs, sector, buf, n); |
| 2174 |
if (ret < 0) { |
| 2175 |
goto ro_cleanup;
|
| 2176 |
} |
| 2177 |
|
| 2178 |
ret = bdrv_write(bs->backing_hd, sector, buf, n); |
| 2179 |
if (ret < 0) { |
| 2180 |
goto ro_cleanup;
|
| 2181 |
} |
| 2182 |
} |
| 2183 |
} |
| 2184 |
|
| 2185 |
if (drv->bdrv_make_empty) {
|
| 2186 |
ret = drv->bdrv_make_empty(bs); |
| 2187 |
if (ret < 0) { |
| 2188 |
goto ro_cleanup;
|
| 2189 |
} |
| 2190 |
bdrv_flush(bs); |
| 2191 |
} |
| 2192 |
|
| 2193 |
/*
|
| 2194 |
* Make sure all data we wrote to the backing device is actually
|
| 2195 |
* stable on disk.
|
| 2196 |
*/
|
| 2197 |
if (bs->backing_hd) {
|
| 2198 |
bdrv_flush(bs->backing_hd); |
| 2199 |
} |
| 2200 |
|
| 2201 |
ret = 0;
|
| 2202 |
ro_cleanup:
|
| 2203 |
g_free(buf); |
| 2204 |
|
| 2205 |
if (ro) {
|
| 2206 |
/* ignoring error return here */
|
| 2207 |
bdrv_reopen(bs->backing_hd, open_flags & ~BDRV_O_RDWR, NULL);
|
| 2208 |
} |
| 2209 |
|
| 2210 |
return ret;
|
| 2211 |
} |
| 2212 |
|
| 2213 |
int bdrv_commit_all(void) |
| 2214 |
{
|
| 2215 |
BlockDriverState *bs; |
| 2216 |
|
| 2217 |
QTAILQ_FOREACH(bs, &bdrv_states, device_list) {
|
| 2218 |
if (bs->drv && bs->backing_hd) {
|
| 2219 |
int ret = bdrv_commit(bs);
|
| 2220 |
if (ret < 0) { |
| 2221 |
return ret;
|
| 2222 |
} |
| 2223 |
} |
| 2224 |
} |
| 2225 |
return 0; |
| 2226 |
} |
| 2227 |
|
| 2228 |
/**
|
| 2229 |
* Remove an active request from the tracked requests list
|
| 2230 |
*
|
| 2231 |
* This function should be called when a tracked request is completing.
|
| 2232 |
*/
|
| 2233 |
static void tracked_request_end(BdrvTrackedRequest *req) |
| 2234 |
{
|
| 2235 |
if (req->serialising) {
|
| 2236 |
req->bs->serialising_in_flight--; |
| 2237 |
} |
| 2238 |
|
| 2239 |
QLIST_REMOVE(req, list); |
| 2240 |
qemu_co_queue_restart_all(&req->wait_queue); |
| 2241 |
} |
| 2242 |
|
| 2243 |
/**
|
| 2244 |
* Add an active request to the tracked requests list
|
| 2245 |
*/
|
| 2246 |
static void tracked_request_begin(BdrvTrackedRequest *req, |
| 2247 |
BlockDriverState *bs, |
| 2248 |
int64_t offset, |
| 2249 |
unsigned int bytes, bool is_write) |
| 2250 |
{
|
| 2251 |
*req = (BdrvTrackedRequest){
|
| 2252 |
.bs = bs, |
| 2253 |
.offset = offset, |
| 2254 |
.bytes = bytes, |
| 2255 |
.is_write = is_write, |
| 2256 |
.co = qemu_coroutine_self(), |
| 2257 |
.serialising = false,
|
| 2258 |
.overlap_offset = offset, |
| 2259 |
.overlap_bytes = bytes, |
| 2260 |
}; |
| 2261 |
|
| 2262 |
qemu_co_queue_init(&req->wait_queue); |
| 2263 |
|
| 2264 |
QLIST_INSERT_HEAD(&bs->tracked_requests, req, list); |
| 2265 |
} |
| 2266 |
|
| 2267 |
static void mark_request_serialising(BdrvTrackedRequest *req, uint64_t align) |
| 2268 |
{
|
| 2269 |
int64_t overlap_offset = req->offset & ~(align - 1);
|
| 2270 |
unsigned int overlap_bytes = ROUND_UP(req->offset + req->bytes, align) |
| 2271 |
- overlap_offset; |
| 2272 |
|
| 2273 |
if (!req->serialising) {
|
| 2274 |
req->bs->serialising_in_flight++; |
| 2275 |
req->serialising = true;
|
| 2276 |
} |
| 2277 |
|
| 2278 |
req->overlap_offset = MIN(req->overlap_offset, overlap_offset); |
| 2279 |
req->overlap_bytes = MAX(req->overlap_bytes, overlap_bytes); |
| 2280 |
} |
| 2281 |
|
| 2282 |
/**
|
| 2283 |
* Round a region to cluster boundaries
|
| 2284 |
*/
|
| 2285 |
void bdrv_round_to_clusters(BlockDriverState *bs,
|
| 2286 |
int64_t sector_num, int nb_sectors,
|
| 2287 |
int64_t *cluster_sector_num, |
| 2288 |
int *cluster_nb_sectors)
|
| 2289 |
{
|
| 2290 |
BlockDriverInfo bdi; |
| 2291 |
|
| 2292 |
if (bdrv_get_info(bs, &bdi) < 0 || bdi.cluster_size == 0) { |
| 2293 |
*cluster_sector_num = sector_num; |
| 2294 |
*cluster_nb_sectors = nb_sectors; |
| 2295 |
} else {
|
| 2296 |
int64_t c = bdi.cluster_size / BDRV_SECTOR_SIZE; |
| 2297 |
*cluster_sector_num = QEMU_ALIGN_DOWN(sector_num, c); |
| 2298 |
*cluster_nb_sectors = QEMU_ALIGN_UP(sector_num - *cluster_sector_num + |
| 2299 |
nb_sectors, c); |
| 2300 |
} |
| 2301 |
} |
| 2302 |
|
| 2303 |
static int bdrv_get_cluster_size(BlockDriverState *bs) |
| 2304 |
{
|
| 2305 |
BlockDriverInfo bdi; |
| 2306 |
int ret;
|
| 2307 |
|
| 2308 |
ret = bdrv_get_info(bs, &bdi); |
| 2309 |
if (ret < 0 || bdi.cluster_size == 0) { |
| 2310 |
return bs->request_alignment;
|
| 2311 |
} else {
|
| 2312 |
return bdi.cluster_size;
|
| 2313 |
} |
| 2314 |
} |
| 2315 |
|
| 2316 |
static bool tracked_request_overlaps(BdrvTrackedRequest *req, |
| 2317 |
int64_t offset, unsigned int bytes) |
| 2318 |
{
|
| 2319 |
/* aaaa bbbb */
|
| 2320 |
if (offset >= req->overlap_offset + req->overlap_bytes) {
|
| 2321 |
return false; |
| 2322 |
} |
| 2323 |
/* bbbb aaaa */
|
| 2324 |
if (req->overlap_offset >= offset + bytes) {
|
| 2325 |
return false; |
| 2326 |
} |
| 2327 |
return true; |
| 2328 |
} |
| 2329 |
|
| 2330 |
static bool coroutine_fn wait_serialising_requests(BdrvTrackedRequest *self) |
| 2331 |
{
|
| 2332 |
BlockDriverState *bs = self->bs; |
| 2333 |
BdrvTrackedRequest *req; |
| 2334 |
bool retry;
|
| 2335 |
bool waited = false; |
| 2336 |
|
| 2337 |
if (!bs->serialising_in_flight) {
|
| 2338 |
return false; |
| 2339 |
} |
| 2340 |
|
| 2341 |
do {
|
| 2342 |
retry = false;
|
| 2343 |
QLIST_FOREACH(req, &bs->tracked_requests, list) {
|
| 2344 |
if (req == self || (!req->serialising && !self->serialising)) {
|
| 2345 |
continue;
|
| 2346 |
} |
| 2347 |
if (tracked_request_overlaps(req, self->overlap_offset,
|
| 2348 |
self->overlap_bytes)) |
| 2349 |
{
|
| 2350 |
/* Hitting this means there was a reentrant request, for
|
| 2351 |
* example, a block driver issuing nested requests. This must
|
| 2352 |
* never happen since it means deadlock.
|
| 2353 |
*/
|
| 2354 |
assert(qemu_coroutine_self() != req->co); |
| 2355 |
|
| 2356 |
/* If the request is already (indirectly) waiting for us, or
|
| 2357 |
* will wait for us as soon as it wakes up, then just go on
|
| 2358 |
* (instead of producing a deadlock in the former case). */
|
| 2359 |
if (!req->waiting_for) {
|
| 2360 |
self->waiting_for = req; |
| 2361 |
qemu_co_queue_wait(&req->wait_queue); |
| 2362 |
self->waiting_for = NULL;
|
| 2363 |
retry = true;
|
| 2364 |
waited = true;
|
| 2365 |
break;
|
| 2366 |
} |
| 2367 |
} |
| 2368 |
} |
| 2369 |
} while (retry);
|
| 2370 |
|
| 2371 |
return waited;
|
| 2372 |
} |
| 2373 |
|
| 2374 |
/*
|
| 2375 |
* Return values:
|
| 2376 |
* 0 - success
|
| 2377 |
* -EINVAL - backing format specified, but no file
|
| 2378 |
* -ENOSPC - can't update the backing file because no space is left in the
|
| 2379 |
* image file header
|
| 2380 |
* -ENOTSUP - format driver doesn't support changing the backing file
|
| 2381 |
*/
|
| 2382 |
int bdrv_change_backing_file(BlockDriverState *bs,
|
| 2383 |
const char *backing_file, const char *backing_fmt) |
| 2384 |
{
|
| 2385 |
BlockDriver *drv = bs->drv; |
| 2386 |
int ret;
|
| 2387 |
|
| 2388 |
/* Backing file format doesn't make sense without a backing file */
|
| 2389 |
if (backing_fmt && !backing_file) {
|
| 2390 |
return -EINVAL;
|
| 2391 |
} |
| 2392 |
|
| 2393 |
if (drv->bdrv_change_backing_file != NULL) { |
| 2394 |
ret = drv->bdrv_change_backing_file(bs, backing_file, backing_fmt); |
| 2395 |
} else {
|
| 2396 |
ret = -ENOTSUP; |
| 2397 |
} |
| 2398 |
|
| 2399 |
if (ret == 0) { |
| 2400 |
pstrcpy(bs->backing_file, sizeof(bs->backing_file), backing_file ?: ""); |
| 2401 |
pstrcpy(bs->backing_format, sizeof(bs->backing_format), backing_fmt ?: ""); |
| 2402 |
} |
| 2403 |
return ret;
|
| 2404 |
} |
| 2405 |
|
| 2406 |
/*
|
| 2407 |
* Finds the image layer in the chain that has 'bs' as its backing file.
|
| 2408 |
*
|
| 2409 |
* active is the current topmost image.
|
| 2410 |
*
|
| 2411 |
* Returns NULL if bs is not found in active's image chain,
|
| 2412 |
* or if active == bs.
|
| 2413 |
*/
|
| 2414 |
BlockDriverState *bdrv_find_overlay(BlockDriverState *active, |
| 2415 |
BlockDriverState *bs) |
| 2416 |
{
|
| 2417 |
BlockDriverState *overlay = NULL;
|
| 2418 |
BlockDriverState *intermediate; |
| 2419 |
|
| 2420 |
assert(active != NULL);
|
| 2421 |
assert(bs != NULL);
|
| 2422 |
|
| 2423 |
/* if bs is the same as active, then by definition it has no overlay
|
| 2424 |
*/
|
| 2425 |
if (active == bs) {
|
| 2426 |
return NULL; |
| 2427 |
} |
| 2428 |
|
| 2429 |
intermediate = active; |
| 2430 |
while (intermediate->backing_hd) {
|
| 2431 |
if (intermediate->backing_hd == bs) {
|
| 2432 |
overlay = intermediate; |
| 2433 |
break;
|
| 2434 |
} |
| 2435 |
intermediate = intermediate->backing_hd; |
| 2436 |
} |
| 2437 |
|
| 2438 |
return overlay;
|
| 2439 |
} |
| 2440 |
|
| 2441 |
typedef struct BlkIntermediateStates { |
| 2442 |
BlockDriverState *bs; |
| 2443 |
QSIMPLEQ_ENTRY(BlkIntermediateStates) entry; |
| 2444 |
} BlkIntermediateStates; |
| 2445 |
|
| 2446 |
|
| 2447 |
/*
|
| 2448 |
* Drops images above 'base' up to and including 'top', and sets the image
|
| 2449 |
* above 'top' to have base as its backing file.
|
| 2450 |
*
|
| 2451 |
* Requires that the overlay to 'top' is opened r/w, so that the backing file
|
| 2452 |
* information in 'bs' can be properly updated.
|
| 2453 |
*
|
| 2454 |
* E.g., this will convert the following chain:
|
| 2455 |
* bottom <- base <- intermediate <- top <- active
|
| 2456 |
*
|
| 2457 |
* to
|
| 2458 |
*
|
| 2459 |
* bottom <- base <- active
|
| 2460 |
*
|
| 2461 |
* It is allowed for bottom==base, in which case it converts:
|
| 2462 |
*
|
| 2463 |
* base <- intermediate <- top <- active
|
| 2464 |
*
|
| 2465 |
* to
|
| 2466 |
*
|
| 2467 |
* base <- active
|
| 2468 |
*
|
| 2469 |
* Error conditions:
|
| 2470 |
* if active == top, that is considered an error
|
| 2471 |
*
|
| 2472 |
*/
|
| 2473 |
int bdrv_drop_intermediate(BlockDriverState *active, BlockDriverState *top,
|
| 2474 |
BlockDriverState *base) |
| 2475 |
{
|
| 2476 |
BlockDriverState *intermediate; |
| 2477 |
BlockDriverState *base_bs = NULL;
|
| 2478 |
BlockDriverState *new_top_bs = NULL;
|
| 2479 |
BlkIntermediateStates *intermediate_state, *next; |
| 2480 |
int ret = -EIO;
|
| 2481 |
|
| 2482 |
QSIMPLEQ_HEAD(states_to_delete, BlkIntermediateStates) states_to_delete; |
| 2483 |
QSIMPLEQ_INIT(&states_to_delete); |
| 2484 |
|
| 2485 |
if (!top->drv || !base->drv) {
|
| 2486 |
goto exit;
|
| 2487 |
} |
| 2488 |
|
| 2489 |
new_top_bs = bdrv_find_overlay(active, top); |
| 2490 |
|
| 2491 |
if (new_top_bs == NULL) { |
| 2492 |
/* we could not find the image above 'top', this is an error */
|
| 2493 |
goto exit;
|
| 2494 |
} |
| 2495 |
|
| 2496 |
/* special case of new_top_bs->backing_hd already pointing to base - nothing
|
| 2497 |
* to do, no intermediate images */
|
| 2498 |
if (new_top_bs->backing_hd == base) {
|
| 2499 |
ret = 0;
|
| 2500 |
goto exit;
|
| 2501 |
} |
| 2502 |
|
| 2503 |
intermediate = top; |
| 2504 |
|
| 2505 |
/* now we will go down through the list, and add each BDS we find
|
| 2506 |
* into our deletion queue, until we hit the 'base'
|
| 2507 |
*/
|
| 2508 |
while (intermediate) {
|
| 2509 |
intermediate_state = g_malloc0(sizeof(BlkIntermediateStates));
|
| 2510 |
intermediate_state->bs = intermediate; |
| 2511 |
QSIMPLEQ_INSERT_TAIL(&states_to_delete, intermediate_state, entry); |
| 2512 |
|
| 2513 |
if (intermediate->backing_hd == base) {
|
| 2514 |
base_bs = intermediate->backing_hd; |
| 2515 |
break;
|
| 2516 |
} |
| 2517 |
intermediate = intermediate->backing_hd; |
| 2518 |
} |
| 2519 |
if (base_bs == NULL) { |
| 2520 |
/* something went wrong, we did not end at the base. safely
|
| 2521 |
* unravel everything, and exit with error */
|
| 2522 |
goto exit;
|
| 2523 |
} |
| 2524 |
|
| 2525 |
/* success - we can delete the intermediate states, and link top->base */
|
| 2526 |
ret = bdrv_change_backing_file(new_top_bs, base_bs->filename, |
| 2527 |
base_bs->drv ? base_bs->drv->format_name : "");
|
| 2528 |
if (ret) {
|
| 2529 |
goto exit;
|
| 2530 |
} |
| 2531 |
new_top_bs->backing_hd = base_bs; |
| 2532 |
|
| 2533 |
bdrv_refresh_limits(new_top_bs); |
| 2534 |
|
| 2535 |
QSIMPLEQ_FOREACH_SAFE(intermediate_state, &states_to_delete, entry, next) {
|
| 2536 |
/* so that bdrv_close() does not recursively close the chain */
|
| 2537 |
intermediate_state->bs->backing_hd = NULL;
|
| 2538 |
bdrv_unref(intermediate_state->bs); |
| 2539 |
} |
| 2540 |
ret = 0;
|
| 2541 |
|
| 2542 |
exit:
|
| 2543 |
QSIMPLEQ_FOREACH_SAFE(intermediate_state, &states_to_delete, entry, next) {
|
| 2544 |
g_free(intermediate_state); |
| 2545 |
} |
| 2546 |
return ret;
|
| 2547 |
} |
| 2548 |
|
| 2549 |
|
| 2550 |
static int bdrv_check_byte_request(BlockDriverState *bs, int64_t offset, |
| 2551 |
size_t size) |
| 2552 |
{
|
| 2553 |
int64_t len; |
| 2554 |
|
| 2555 |
if (!bdrv_is_inserted(bs))
|
| 2556 |
return -ENOMEDIUM;
|
| 2557 |
|
| 2558 |
if (bs->growable)
|
| 2559 |
return 0; |
| 2560 |
|
| 2561 |
len = bdrv_getlength(bs); |
| 2562 |
|
| 2563 |
if (offset < 0) |
| 2564 |
return -EIO;
|
| 2565 |
|
| 2566 |
if ((offset > len) || (len - offset < size))
|
| 2567 |
return -EIO;
|
| 2568 |
|
| 2569 |
return 0; |
| 2570 |
} |
| 2571 |
|
| 2572 |
static int bdrv_check_request(BlockDriverState *bs, int64_t sector_num, |
| 2573 |
int nb_sectors)
|
| 2574 |
{
|
| 2575 |
return bdrv_check_byte_request(bs, sector_num * BDRV_SECTOR_SIZE,
|
| 2576 |
nb_sectors * BDRV_SECTOR_SIZE); |
| 2577 |
} |
| 2578 |
|
| 2579 |
typedef struct RwCo { |
| 2580 |
BlockDriverState *bs; |
| 2581 |
int64_t offset; |
| 2582 |
QEMUIOVector *qiov; |
| 2583 |
bool is_write;
|
| 2584 |
int ret;
|
| 2585 |
BdrvRequestFlags flags; |
| 2586 |
} RwCo; |
| 2587 |
|
| 2588 |
static void coroutine_fn bdrv_rw_co_entry(void *opaque) |
| 2589 |
{
|
| 2590 |
RwCo *rwco = opaque; |
| 2591 |
|
| 2592 |
if (!rwco->is_write) {
|
| 2593 |
rwco->ret = bdrv_co_do_preadv(rwco->bs, rwco->offset, |
| 2594 |
rwco->qiov->size, rwco->qiov, |
| 2595 |
rwco->flags); |
| 2596 |
} else {
|
| 2597 |
rwco->ret = bdrv_co_do_pwritev(rwco->bs, rwco->offset, |
| 2598 |
rwco->qiov->size, rwco->qiov, |
| 2599 |
rwco->flags); |
| 2600 |
} |
| 2601 |
} |
| 2602 |
|
| 2603 |
/*
|
| 2604 |
* Process a vectored synchronous request using coroutines
|
| 2605 |
*/
|
| 2606 |
static int bdrv_prwv_co(BlockDriverState *bs, int64_t offset, |
| 2607 |
QEMUIOVector *qiov, bool is_write,
|
| 2608 |
BdrvRequestFlags flags) |
| 2609 |
{
|
| 2610 |
Coroutine *co; |
| 2611 |
RwCo rwco = {
|
| 2612 |
.bs = bs, |
| 2613 |
.offset = offset, |
| 2614 |
.qiov = qiov, |
| 2615 |
.is_write = is_write, |
| 2616 |
.ret = NOT_DONE, |
| 2617 |
.flags = flags, |
| 2618 |
}; |
| 2619 |
|
| 2620 |
/**
|
| 2621 |
* In sync call context, when the vcpu is blocked, this throttling timer
|
| 2622 |
* will not fire; so the I/O throttling function has to be disabled here
|
| 2623 |
* if it has been enabled.
|
| 2624 |
*/
|
| 2625 |
if (bs->io_limits_enabled) {
|
| 2626 |
fprintf(stderr, "Disabling I/O throttling on '%s' due "
|
| 2627 |
"to synchronous I/O.\n", bdrv_get_device_name(bs));
|
| 2628 |
bdrv_io_limits_disable(bs); |
| 2629 |
} |
| 2630 |
|
| 2631 |
if (qemu_in_coroutine()) {
|
| 2632 |
/* Fast-path if already in coroutine context */
|
| 2633 |
bdrv_rw_co_entry(&rwco); |
| 2634 |
} else {
|
| 2635 |
co = qemu_coroutine_create(bdrv_rw_co_entry); |
| 2636 |
qemu_coroutine_enter(co, &rwco); |
| 2637 |
while (rwco.ret == NOT_DONE) {
|
| 2638 |
qemu_aio_wait(); |
| 2639 |
} |
| 2640 |
} |
| 2641 |
return rwco.ret;
|
| 2642 |
} |
| 2643 |
|
| 2644 |
/*
|
| 2645 |
* Process a synchronous request using coroutines
|
| 2646 |
*/
|
| 2647 |
static int bdrv_rw_co(BlockDriverState *bs, int64_t sector_num, uint8_t *buf, |
| 2648 |
int nb_sectors, bool is_write, BdrvRequestFlags flags) |
| 2649 |
{
|
| 2650 |
QEMUIOVector qiov; |
| 2651 |
struct iovec iov = {
|
| 2652 |
.iov_base = (void *)buf,
|
| 2653 |
.iov_len = nb_sectors * BDRV_SECTOR_SIZE, |
| 2654 |
}; |
| 2655 |
|
| 2656 |
qemu_iovec_init_external(&qiov, &iov, 1);
|
| 2657 |
return bdrv_prwv_co(bs, sector_num << BDRV_SECTOR_BITS,
|
| 2658 |
&qiov, is_write, flags); |
| 2659 |
} |
| 2660 |
|
| 2661 |
/* return < 0 if error. See bdrv_write() for the return codes */
|
| 2662 |
int bdrv_read(BlockDriverState *bs, int64_t sector_num,
|
| 2663 |
uint8_t *buf, int nb_sectors)
|
| 2664 |
{
|
| 2665 |
return bdrv_rw_co(bs, sector_num, buf, nb_sectors, false, 0); |
| 2666 |
} |
| 2667 |
|
| 2668 |
/* Just like bdrv_read(), but with I/O throttling temporarily disabled */
|
| 2669 |
int bdrv_read_unthrottled(BlockDriverState *bs, int64_t sector_num,
|
| 2670 |
uint8_t *buf, int nb_sectors)
|
| 2671 |
{
|
| 2672 |
bool enabled;
|
| 2673 |
int ret;
|
| 2674 |
|
| 2675 |
enabled = bs->io_limits_enabled; |
| 2676 |
bs->io_limits_enabled = false;
|
| 2677 |
ret = bdrv_read(bs, sector_num, buf, nb_sectors); |
| 2678 |
bs->io_limits_enabled = enabled; |
| 2679 |
return ret;
|
| 2680 |
} |
| 2681 |
|
| 2682 |
/* Return < 0 if error. Important errors are:
|
| 2683 |
-EIO generic I/O error (may happen for all errors)
|
| 2684 |
-ENOMEDIUM No media inserted.
|
| 2685 |
-EINVAL Invalid sector number or nb_sectors
|
| 2686 |
-EACCES Trying to write a read-only device
|
| 2687 |
*/
|
| 2688 |
int bdrv_write(BlockDriverState *bs, int64_t sector_num,
|
| 2689 |
const uint8_t *buf, int nb_sectors) |
| 2690 |
{
|
| 2691 |
return bdrv_rw_co(bs, sector_num, (uint8_t *)buf, nb_sectors, true, 0); |
| 2692 |
} |
| 2693 |
|
| 2694 |
int bdrv_write_zeroes(BlockDriverState *bs, int64_t sector_num,
|
| 2695 |
int nb_sectors, BdrvRequestFlags flags)
|
| 2696 |
{
|
| 2697 |
return bdrv_rw_co(bs, sector_num, NULL, nb_sectors, true, |
| 2698 |
BDRV_REQ_ZERO_WRITE | flags); |
| 2699 |
} |
| 2700 |
|
| 2701 |
/*
|
| 2702 |
* Completely zero out a block device with the help of bdrv_write_zeroes.
|
| 2703 |
* The operation is sped up by checking the block status and only writing
|
| 2704 |
* zeroes to the device if they currently do not return zeroes. Optional
|
| 2705 |
* flags are passed through to bdrv_write_zeroes (e.g. BDRV_REQ_MAY_UNMAP).
|
| 2706 |
*
|
| 2707 |
* Returns < 0 on error, 0 on success. For error codes see bdrv_write().
|
| 2708 |
*/
|
| 2709 |
int bdrv_make_zero(BlockDriverState *bs, BdrvRequestFlags flags)
|
| 2710 |
{
|
| 2711 |
int64_t target_size = bdrv_getlength(bs) / BDRV_SECTOR_SIZE; |
| 2712 |
int64_t ret, nb_sectors, sector_num = 0;
|
| 2713 |
int n;
|
| 2714 |
|
| 2715 |
for (;;) {
|
| 2716 |
nb_sectors = target_size - sector_num; |
| 2717 |
if (nb_sectors <= 0) { |
| 2718 |
return 0; |
| 2719 |
} |
| 2720 |
if (nb_sectors > INT_MAX) {
|
| 2721 |
nb_sectors = INT_MAX; |
| 2722 |
} |
| 2723 |
ret = bdrv_get_block_status(bs, sector_num, nb_sectors, &n); |
| 2724 |
if (ret < 0) { |
| 2725 |
error_report("error getting block status at sector %" PRId64 ": %s", |
| 2726 |
sector_num, strerror(-ret)); |
| 2727 |
return ret;
|
| 2728 |
} |
| 2729 |
if (ret & BDRV_BLOCK_ZERO) {
|
| 2730 |
sector_num += n; |
| 2731 |
continue;
|
| 2732 |
} |
| 2733 |
ret = bdrv_write_zeroes(bs, sector_num, n, flags); |
| 2734 |
if (ret < 0) { |
| 2735 |
error_report("error writing zeroes at sector %" PRId64 ": %s", |
| 2736 |
sector_num, strerror(-ret)); |
| 2737 |
return ret;
|
| 2738 |
} |
| 2739 |
sector_num += n; |
| 2740 |
} |
| 2741 |
} |
| 2742 |
|
| 2743 |
int bdrv_pread(BlockDriverState *bs, int64_t offset, void *buf, int bytes) |
| 2744 |
{
|
| 2745 |
QEMUIOVector qiov; |
| 2746 |
struct iovec iov = {
|
| 2747 |
.iov_base = (void *)buf,
|
| 2748 |
.iov_len = bytes, |
| 2749 |
}; |
| 2750 |
int ret;
|
| 2751 |
|
| 2752 |
if (bytes < 0) { |
| 2753 |
return -EINVAL;
|
| 2754 |
} |
| 2755 |
|
| 2756 |
qemu_iovec_init_external(&qiov, &iov, 1);
|
| 2757 |
ret = bdrv_prwv_co(bs, offset, &qiov, false, 0); |
| 2758 |
if (ret < 0) { |
| 2759 |
return ret;
|
| 2760 |
} |
| 2761 |
|
| 2762 |
return bytes;
|
| 2763 |
} |
| 2764 |
|
| 2765 |
int bdrv_pwritev(BlockDriverState *bs, int64_t offset, QEMUIOVector *qiov)
|
| 2766 |
{
|
| 2767 |
int ret;
|
| 2768 |
|
| 2769 |
ret = bdrv_prwv_co(bs, offset, qiov, true, 0); |
| 2770 |
if (ret < 0) { |
| 2771 |
return ret;
|
| 2772 |
} |
| 2773 |
|
| 2774 |
return qiov->size;
|
| 2775 |
} |
| 2776 |
|
| 2777 |
int bdrv_pwrite(BlockDriverState *bs, int64_t offset,
|
| 2778 |
const void *buf, int bytes) |
| 2779 |
{
|
| 2780 |
QEMUIOVector qiov; |
| 2781 |
struct iovec iov = {
|
| 2782 |
.iov_base = (void *) buf,
|
| 2783 |
.iov_len = bytes, |
| 2784 |
}; |
| 2785 |
|
| 2786 |
if (bytes < 0) { |
| 2787 |
return -EINVAL;
|
| 2788 |
} |
| 2789 |
|
| 2790 |
qemu_iovec_init_external(&qiov, &iov, 1);
|
| 2791 |
return bdrv_pwritev(bs, offset, &qiov);
|
| 2792 |
} |
| 2793 |
|
| 2794 |
/*
|
| 2795 |
* Writes to the file and ensures that no writes are reordered across this
|
| 2796 |
* request (acts as a barrier)
|
| 2797 |
*
|
| 2798 |
* Returns 0 on success, -errno in error cases.
|
| 2799 |
*/
|
| 2800 |
int bdrv_pwrite_sync(BlockDriverState *bs, int64_t offset,
|
| 2801 |
const void *buf, int count) |
| 2802 |
{
|
| 2803 |
int ret;
|
| 2804 |
|
| 2805 |
ret = bdrv_pwrite(bs, offset, buf, count); |
| 2806 |
if (ret < 0) { |
| 2807 |
return ret;
|
| 2808 |
} |
| 2809 |
|
| 2810 |
/* No flush needed for cache modes that already do it */
|
| 2811 |
if (bs->enable_write_cache) {
|
| 2812 |
bdrv_flush(bs); |
| 2813 |
} |
| 2814 |
|
| 2815 |
return 0; |
| 2816 |
} |
| 2817 |
|
| 2818 |
static int coroutine_fn bdrv_co_do_copy_on_readv(BlockDriverState *bs, |
| 2819 |
int64_t sector_num, int nb_sectors, QEMUIOVector *qiov)
|
| 2820 |
{
|
| 2821 |
/* Perform I/O through a temporary buffer so that users who scribble over
|
| 2822 |
* their read buffer while the operation is in progress do not end up
|
| 2823 |
* modifying the image file. This is critical for zero-copy guest I/O
|
| 2824 |
* where anything might happen inside guest memory.
|
| 2825 |
*/
|
| 2826 |
void *bounce_buffer;
|
| 2827 |
|
| 2828 |
BlockDriver *drv = bs->drv; |
| 2829 |
struct iovec iov;
|
| 2830 |
QEMUIOVector bounce_qiov; |
| 2831 |
int64_t cluster_sector_num; |
| 2832 |
int cluster_nb_sectors;
|
| 2833 |
size_t skip_bytes; |
| 2834 |
int ret;
|
| 2835 |
|
| 2836 |
/* Cover entire cluster so no additional backing file I/O is required when
|
| 2837 |
* allocating cluster in the image file.
|
| 2838 |
*/
|
| 2839 |
bdrv_round_to_clusters(bs, sector_num, nb_sectors, |
| 2840 |
&cluster_sector_num, &cluster_nb_sectors); |
| 2841 |
|
| 2842 |
trace_bdrv_co_do_copy_on_readv(bs, sector_num, nb_sectors, |
| 2843 |
cluster_sector_num, cluster_nb_sectors); |
| 2844 |
|
| 2845 |
iov.iov_len = cluster_nb_sectors * BDRV_SECTOR_SIZE; |
| 2846 |
iov.iov_base = bounce_buffer = qemu_blockalign(bs, iov.iov_len); |
| 2847 |
qemu_iovec_init_external(&bounce_qiov, &iov, 1);
|
| 2848 |
|
| 2849 |
ret = drv->bdrv_co_readv(bs, cluster_sector_num, cluster_nb_sectors, |
| 2850 |
&bounce_qiov); |
| 2851 |
if (ret < 0) { |
| 2852 |
goto err;
|
| 2853 |
} |
| 2854 |
|
| 2855 |
if (drv->bdrv_co_write_zeroes &&
|
| 2856 |
buffer_is_zero(bounce_buffer, iov.iov_len)) {
|
| 2857 |
ret = bdrv_co_do_write_zeroes(bs, cluster_sector_num, |
| 2858 |
cluster_nb_sectors, 0);
|
| 2859 |
} else {
|
| 2860 |
/* This does not change the data on the disk, it is not necessary
|
| 2861 |
* to flush even in cache=writethrough mode.
|
| 2862 |
*/
|
| 2863 |
ret = drv->bdrv_co_writev(bs, cluster_sector_num, cluster_nb_sectors, |
| 2864 |
&bounce_qiov); |
| 2865 |
} |
| 2866 |
|
| 2867 |
if (ret < 0) { |
| 2868 |
/* It might be okay to ignore write errors for guest requests. If this
|
| 2869 |
* is a deliberate copy-on-read then we don't want to ignore the error.
|
| 2870 |
* Simply report it in all cases.
|
| 2871 |
*/
|
| 2872 |
goto err;
|
| 2873 |
} |
| 2874 |
|
| 2875 |
skip_bytes = (sector_num - cluster_sector_num) * BDRV_SECTOR_SIZE; |
| 2876 |
qemu_iovec_from_buf(qiov, 0, bounce_buffer + skip_bytes,
|
| 2877 |
nb_sectors * BDRV_SECTOR_SIZE); |
| 2878 |
|
| 2879 |
err:
|
| 2880 |
qemu_vfree(bounce_buffer); |
| 2881 |
return ret;
|
| 2882 |
} |
| 2883 |
|
| 2884 |
/*
|
| 2885 |
* Forwards an already correctly aligned request to the BlockDriver. This
|
| 2886 |
* handles copy on read and zeroing after EOF; any other features must be
|
| 2887 |
* implemented by the caller.
|
| 2888 |
*/
|
| 2889 |
static int coroutine_fn bdrv_aligned_preadv(BlockDriverState *bs, |
| 2890 |
BdrvTrackedRequest *req, int64_t offset, unsigned int bytes, |
| 2891 |
int64_t align, QEMUIOVector *qiov, int flags)
|
| 2892 |
{
|
| 2893 |
BlockDriver *drv = bs->drv; |
| 2894 |
int ret;
|
| 2895 |
|
| 2896 |
int64_t sector_num = offset >> BDRV_SECTOR_BITS; |
| 2897 |
unsigned int nb_sectors = bytes >> BDRV_SECTOR_BITS; |
| 2898 |
|
| 2899 |
assert((offset & (BDRV_SECTOR_SIZE - 1)) == 0); |
| 2900 |
assert((bytes & (BDRV_SECTOR_SIZE - 1)) == 0); |
| 2901 |
|
| 2902 |
/* Handle Copy on Read and associated serialisation */
|
| 2903 |
if (flags & BDRV_REQ_COPY_ON_READ) {
|
| 2904 |
/* If we touch the same cluster it counts as an overlap. This
|
| 2905 |
* guarantees that allocating writes will be serialized and not race
|
| 2906 |
* with each other for the same cluster. For example, in copy-on-read
|
| 2907 |
* it ensures that the CoR read and write operations are atomic and
|
| 2908 |
* guest writes cannot interleave between them. */
|
| 2909 |
mark_request_serialising(req, bdrv_get_cluster_size(bs)); |
| 2910 |
} |
| 2911 |
|
| 2912 |
wait_serialising_requests(req); |
| 2913 |
|
| 2914 |
if (flags & BDRV_REQ_COPY_ON_READ) {
|
| 2915 |
int pnum;
|
| 2916 |
|
| 2917 |
ret = bdrv_is_allocated(bs, sector_num, nb_sectors, &pnum); |
| 2918 |
if (ret < 0) { |
| 2919 |
goto out;
|
| 2920 |
} |
| 2921 |
|
| 2922 |
if (!ret || pnum != nb_sectors) {
|
| 2923 |
ret = bdrv_co_do_copy_on_readv(bs, sector_num, nb_sectors, qiov); |
| 2924 |
goto out;
|
| 2925 |
} |
| 2926 |
} |
| 2927 |
|
| 2928 |
/* Forward the request to the BlockDriver */
|
| 2929 |
if (!(bs->zero_beyond_eof && bs->growable)) {
|
| 2930 |
ret = drv->bdrv_co_readv(bs, sector_num, nb_sectors, qiov); |
| 2931 |
} else {
|
| 2932 |
/* Read zeros after EOF of growable BDSes */
|
| 2933 |
int64_t len, total_sectors, max_nb_sectors; |
| 2934 |
|
| 2935 |
len = bdrv_getlength(bs); |
| 2936 |
if (len < 0) { |
| 2937 |
ret = len; |
| 2938 |
goto out;
|
| 2939 |
} |
| 2940 |
|
| 2941 |
total_sectors = DIV_ROUND_UP(len, BDRV_SECTOR_SIZE); |
| 2942 |
max_nb_sectors = ROUND_UP(MAX(0, total_sectors - sector_num),
|
| 2943 |
align >> BDRV_SECTOR_BITS); |
| 2944 |
if (max_nb_sectors > 0) { |
| 2945 |
ret = drv->bdrv_co_readv(bs, sector_num, |
| 2946 |
MIN(nb_sectors, max_nb_sectors), qiov); |
| 2947 |
} else {
|
| 2948 |
ret = 0;
|
| 2949 |
} |
| 2950 |
|
| 2951 |
/* Reading beyond end of file is supposed to produce zeroes */
|
| 2952 |
if (ret == 0 && total_sectors < sector_num + nb_sectors) { |
| 2953 |
uint64_t offset = MAX(0, total_sectors - sector_num);
|
| 2954 |
uint64_t bytes = (sector_num + nb_sectors - offset) * |
| 2955 |
BDRV_SECTOR_SIZE; |
| 2956 |
qemu_iovec_memset(qiov, offset * BDRV_SECTOR_SIZE, 0, bytes);
|
| 2957 |
} |
| 2958 |
} |
| 2959 |
|
| 2960 |
out:
|
| 2961 |
return ret;
|
| 2962 |
} |
| 2963 |
|
| 2964 |
/*
|
| 2965 |
* Handle a read request in coroutine context
|
| 2966 |
*/
|
| 2967 |
static int coroutine_fn bdrv_co_do_preadv(BlockDriverState *bs, |
| 2968 |
int64_t offset, unsigned int bytes, QEMUIOVector *qiov, |
| 2969 |
BdrvRequestFlags flags) |
| 2970 |
{
|
| 2971 |
BlockDriver *drv = bs->drv; |
| 2972 |
BdrvTrackedRequest req; |
| 2973 |
|
| 2974 |
/* TODO Lift BDRV_SECTOR_SIZE restriction in BlockDriver interface */
|
| 2975 |
uint64_t align = MAX(BDRV_SECTOR_SIZE, bs->request_alignment); |
| 2976 |
uint8_t *head_buf = NULL;
|
| 2977 |
uint8_t *tail_buf = NULL;
|
| 2978 |
QEMUIOVector local_qiov; |
| 2979 |
bool use_local_qiov = false; |
| 2980 |
int ret;
|
| 2981 |
|
| 2982 |
if (!drv) {
|
| 2983 |
return -ENOMEDIUM;
|
| 2984 |
} |
| 2985 |
if (bdrv_check_byte_request(bs, offset, bytes)) {
|
| 2986 |
return -EIO;
|
| 2987 |
} |
| 2988 |
|
| 2989 |
if (bs->copy_on_read) {
|
| 2990 |
flags |= BDRV_REQ_COPY_ON_READ; |
| 2991 |
} |
| 2992 |
|
| 2993 |
/* throttling disk I/O */
|
| 2994 |
if (bs->io_limits_enabled) {
|
| 2995 |
bdrv_io_limits_intercept(bs, bytes, false);
|
| 2996 |
} |
| 2997 |
|
| 2998 |
/* Align read if necessary by padding qiov */
|
| 2999 |
if (offset & (align - 1)) { |
| 3000 |
head_buf = qemu_blockalign(bs, align); |
| 3001 |
qemu_iovec_init(&local_qiov, qiov->niov + 2);
|
| 3002 |
qemu_iovec_add(&local_qiov, head_buf, offset & (align - 1));
|
| 3003 |
qemu_iovec_concat(&local_qiov, qiov, 0, qiov->size);
|
| 3004 |
use_local_qiov = true;
|
| 3005 |
|
| 3006 |
bytes += offset & (align - 1);
|
| 3007 |
offset = offset & ~(align - 1);
|
| 3008 |
} |
| 3009 |
|
| 3010 |
if ((offset + bytes) & (align - 1)) { |
| 3011 |
if (!use_local_qiov) {
|
| 3012 |
qemu_iovec_init(&local_qiov, qiov->niov + 1);
|
| 3013 |
qemu_iovec_concat(&local_qiov, qiov, 0, qiov->size);
|
| 3014 |
use_local_qiov = true;
|
| 3015 |
} |
| 3016 |
tail_buf = qemu_blockalign(bs, align); |
| 3017 |
qemu_iovec_add(&local_qiov, tail_buf, |
| 3018 |
align - ((offset + bytes) & (align - 1)));
|
| 3019 |
|
| 3020 |
bytes = ROUND_UP(bytes, align); |
| 3021 |
} |
| 3022 |
|
| 3023 |
tracked_request_begin(&req, bs, offset, bytes, false);
|
| 3024 |
ret = bdrv_aligned_preadv(bs, &req, offset, bytes, align, |
| 3025 |
use_local_qiov ? &local_qiov : qiov, |
| 3026 |
flags); |
| 3027 |
tracked_request_end(&req); |
| 3028 |
|
| 3029 |
if (use_local_qiov) {
|
| 3030 |
qemu_iovec_destroy(&local_qiov); |
| 3031 |
qemu_vfree(head_buf); |
| 3032 |
qemu_vfree(tail_buf); |
| 3033 |
} |
| 3034 |
|
| 3035 |
return ret;
|
| 3036 |
} |
| 3037 |
|
| 3038 |
static int coroutine_fn bdrv_co_do_readv(BlockDriverState *bs, |
| 3039 |
int64_t sector_num, int nb_sectors, QEMUIOVector *qiov,
|
| 3040 |
BdrvRequestFlags flags) |
| 3041 |
{
|
| 3042 |
if (nb_sectors < 0 || nb_sectors > (UINT_MAX >> BDRV_SECTOR_BITS)) { |
| 3043 |
return -EINVAL;
|
| 3044 |
} |
| 3045 |
|
| 3046 |
return bdrv_co_do_preadv(bs, sector_num << BDRV_SECTOR_BITS,
|
| 3047 |
nb_sectors << BDRV_SECTOR_BITS, qiov, flags); |
| 3048 |
} |
| 3049 |
|
| 3050 |
int coroutine_fn bdrv_co_readv(BlockDriverState *bs, int64_t sector_num,
|
| 3051 |
int nb_sectors, QEMUIOVector *qiov)
|
| 3052 |
{
|
| 3053 |
trace_bdrv_co_readv(bs, sector_num, nb_sectors); |
| 3054 |
|
| 3055 |
return bdrv_co_do_readv(bs, sector_num, nb_sectors, qiov, 0); |
| 3056 |
} |
| 3057 |
|
| 3058 |
int coroutine_fn bdrv_co_copy_on_readv(BlockDriverState *bs,
|
| 3059 |
int64_t sector_num, int nb_sectors, QEMUIOVector *qiov)
|
| 3060 |
{
|
| 3061 |
trace_bdrv_co_copy_on_readv(bs, sector_num, nb_sectors); |
| 3062 |
|
| 3063 |
return bdrv_co_do_readv(bs, sector_num, nb_sectors, qiov,
|
| 3064 |
BDRV_REQ_COPY_ON_READ); |
| 3065 |
} |
| 3066 |
|
| 3067 |
/* if no limit is specified in the BlockLimits use a default
|
| 3068 |
* of 32768 512-byte sectors (16 MiB) per request.
|
| 3069 |
*/
|
| 3070 |
#define MAX_WRITE_ZEROES_DEFAULT 32768 |
| 3071 |
|
| 3072 |
static int coroutine_fn bdrv_co_do_write_zeroes(BlockDriverState *bs, |
| 3073 |
int64_t sector_num, int nb_sectors, BdrvRequestFlags flags)
|
| 3074 |
{
|
| 3075 |
BlockDriver *drv = bs->drv; |
| 3076 |
QEMUIOVector qiov; |
| 3077 |
struct iovec iov = {0}; |
| 3078 |
int ret = 0; |
| 3079 |
|
| 3080 |
int max_write_zeroes = bs->bl.max_write_zeroes ?
|
| 3081 |
bs->bl.max_write_zeroes : MAX_WRITE_ZEROES_DEFAULT; |
| 3082 |
|
| 3083 |
while (nb_sectors > 0 && !ret) { |
| 3084 |
int num = nb_sectors;
|
| 3085 |
|
| 3086 |
/* Align request. Block drivers can expect the "bulk" of the request
|
| 3087 |
* to be aligned.
|
| 3088 |
*/
|
| 3089 |
if (bs->bl.write_zeroes_alignment
|
| 3090 |
&& num > bs->bl.write_zeroes_alignment) {
|
| 3091 |
if (sector_num % bs->bl.write_zeroes_alignment != 0) { |
| 3092 |
/* Make a small request up to the first aligned sector. */
|
| 3093 |
num = bs->bl.write_zeroes_alignment; |
| 3094 |
num -= sector_num % bs->bl.write_zeroes_alignment; |
| 3095 |
} else if ((sector_num + num) % bs->bl.write_zeroes_alignment != 0) { |
| 3096 |
/* Shorten the request to the last aligned sector. num cannot
|
| 3097 |
* underflow because num > bs->bl.write_zeroes_alignment.
|
| 3098 |
*/
|
| 3099 |
num -= (sector_num + num) % bs->bl.write_zeroes_alignment; |
| 3100 |
} |
| 3101 |
} |
| 3102 |
|
| 3103 |
/* limit request size */
|
| 3104 |
if (num > max_write_zeroes) {
|
| 3105 |
num = max_write_zeroes; |
| 3106 |
} |
| 3107 |
|
| 3108 |
ret = -ENOTSUP; |
| 3109 |
/* First try the efficient write zeroes operation */
|
| 3110 |
if (drv->bdrv_co_write_zeroes) {
|
| 3111 |
ret = drv->bdrv_co_write_zeroes(bs, sector_num, num, flags); |
| 3112 |
} |
| 3113 |
|
| 3114 |
if (ret == -ENOTSUP) {
|
| 3115 |
/* Fall back to bounce buffer if write zeroes is unsupported */
|
| 3116 |
iov.iov_len = num * BDRV_SECTOR_SIZE; |
| 3117 |
if (iov.iov_base == NULL) { |
| 3118 |
iov.iov_base = qemu_blockalign(bs, num * BDRV_SECTOR_SIZE); |
| 3119 |
memset(iov.iov_base, 0, num * BDRV_SECTOR_SIZE);
|
| 3120 |
} |
| 3121 |
qemu_iovec_init_external(&qiov, &iov, 1);
|
| 3122 |
|
| 3123 |
ret = drv->bdrv_co_writev(bs, sector_num, num, &qiov); |
| 3124 |
|
| 3125 |
/* Keep bounce buffer around if it is big enough for all
|
| 3126 |
* all future requests.
|
| 3127 |
*/
|
| 3128 |
if (num < max_write_zeroes) {
|
| 3129 |
qemu_vfree(iov.iov_base); |
| 3130 |
iov.iov_base = NULL;
|
| 3131 |
} |
| 3132 |
} |
| 3133 |
|
| 3134 |
sector_num += num; |
| 3135 |
nb_sectors -= num; |
| 3136 |
} |
| 3137 |
|
| 3138 |
qemu_vfree(iov.iov_base); |
| 3139 |
return ret;
|
| 3140 |
} |
| 3141 |
|
| 3142 |
/*
|
| 3143 |
* Forwards an already correctly aligned write request to the BlockDriver.
|
| 3144 |
*/
|
| 3145 |
static int coroutine_fn bdrv_aligned_pwritev(BlockDriverState *bs, |
| 3146 |
BdrvTrackedRequest *req, int64_t offset, unsigned int bytes, |
| 3147 |
QEMUIOVector *qiov, int flags)
|
| 3148 |
{
|
| 3149 |
BlockDriver *drv = bs->drv; |
| 3150 |
bool waited;
|
| 3151 |
int ret;
|
| 3152 |
|
| 3153 |
int64_t sector_num = offset >> BDRV_SECTOR_BITS; |
| 3154 |
unsigned int nb_sectors = bytes >> BDRV_SECTOR_BITS; |
| 3155 |
|
| 3156 |
assert((offset & (BDRV_SECTOR_SIZE - 1)) == 0); |
| 3157 |
assert((bytes & (BDRV_SECTOR_SIZE - 1)) == 0); |
| 3158 |
|
| 3159 |
waited = wait_serialising_requests(req); |
| 3160 |
assert(!waited || !req->serialising); |
| 3161 |
assert(req->overlap_offset <= offset); |
| 3162 |
assert(offset + bytes <= req->overlap_offset + req->overlap_bytes); |
| 3163 |
|
| 3164 |
ret = notifier_with_return_list_notify(&bs->before_write_notifiers, req); |
| 3165 |
|
| 3166 |
if (ret < 0) { |
| 3167 |
/* Do nothing, write notifier decided to fail this request */
|
| 3168 |
} else if (flags & BDRV_REQ_ZERO_WRITE) { |
| 3169 |
BLKDBG_EVENT(bs, BLKDBG_PWRITEV_ZERO); |
| 3170 |
ret = bdrv_co_do_write_zeroes(bs, sector_num, nb_sectors, flags); |
| 3171 |
} else {
|
| 3172 |
BLKDBG_EVENT(bs, BLKDBG_PWRITEV); |
| 3173 |
ret = drv->bdrv_co_writev(bs, sector_num, nb_sectors, qiov); |
| 3174 |
} |
| 3175 |
BLKDBG_EVENT(bs, BLKDBG_PWRITEV_DONE); |
| 3176 |
|
| 3177 |
if (ret == 0 && !bs->enable_write_cache) { |
| 3178 |
ret = bdrv_co_flush(bs); |
| 3179 |
} |
| 3180 |
|
| 3181 |
bdrv_set_dirty(bs, sector_num, nb_sectors); |
| 3182 |
|
| 3183 |
if (bs->wr_highest_sector < sector_num + nb_sectors - 1) { |
| 3184 |
bs->wr_highest_sector = sector_num + nb_sectors - 1;
|
| 3185 |
} |
| 3186 |
if (bs->growable && ret >= 0) { |
| 3187 |
bs->total_sectors = MAX(bs->total_sectors, sector_num + nb_sectors); |
| 3188 |
} |
| 3189 |
|
| 3190 |
return ret;
|
| 3191 |
} |
| 3192 |
|
| 3193 |
/*
|
| 3194 |
* Handle a write request in coroutine context
|
| 3195 |
*/
|
| 3196 |
static int coroutine_fn bdrv_co_do_pwritev(BlockDriverState *bs, |
| 3197 |
int64_t offset, unsigned int bytes, QEMUIOVector *qiov, |
| 3198 |
BdrvRequestFlags flags) |
| 3199 |
{
|
| 3200 |
BdrvTrackedRequest req; |
| 3201 |
/* TODO Lift BDRV_SECTOR_SIZE restriction in BlockDriver interface */
|
| 3202 |
uint64_t align = MAX(BDRV_SECTOR_SIZE, bs->request_alignment); |
| 3203 |
uint8_t *head_buf = NULL;
|
| 3204 |
uint8_t *tail_buf = NULL;
|
| 3205 |
QEMUIOVector local_qiov; |
| 3206 |
bool use_local_qiov = false; |
| 3207 |
int ret;
|
| 3208 |
|
| 3209 |
if (!bs->drv) {
|
| 3210 |
return -ENOMEDIUM;
|
| 3211 |
} |
| 3212 |
if (bs->read_only) {
|
| 3213 |
return -EACCES;
|
| 3214 |
} |
| 3215 |
if (bdrv_check_byte_request(bs, offset, bytes)) {
|
| 3216 |
return -EIO;
|
| 3217 |
} |
| 3218 |
|
| 3219 |
/* throttling disk I/O */
|
| 3220 |
if (bs->io_limits_enabled) {
|
| 3221 |
bdrv_io_limits_intercept(bs, bytes, true);
|
| 3222 |
} |
| 3223 |
|
| 3224 |
/*
|
| 3225 |
* Align write if necessary by performing a read-modify-write cycle.
|
| 3226 |
* Pad qiov with the read parts and be sure to have a tracked request not
|
| 3227 |
* only for bdrv_aligned_pwritev, but also for the reads of the RMW cycle.
|
| 3228 |
*/
|
| 3229 |
tracked_request_begin(&req, bs, offset, bytes, true);
|
| 3230 |
|
| 3231 |
if (offset & (align - 1)) { |
| 3232 |
QEMUIOVector head_qiov; |
| 3233 |
struct iovec head_iov;
|
| 3234 |
|
| 3235 |
mark_request_serialising(&req, align); |
| 3236 |
wait_serialising_requests(&req); |
| 3237 |
|
| 3238 |
head_buf = qemu_blockalign(bs, align); |
| 3239 |
head_iov = (struct iovec) {
|
| 3240 |
.iov_base = head_buf, |
| 3241 |
.iov_len = align, |
| 3242 |
}; |
| 3243 |
qemu_iovec_init_external(&head_qiov, &head_iov, 1);
|
| 3244 |
|
| 3245 |
BLKDBG_EVENT(bs, BLKDBG_PWRITEV_RMW_HEAD); |
| 3246 |
ret = bdrv_aligned_preadv(bs, &req, offset & ~(align - 1), align,
|
| 3247 |
align, &head_qiov, 0);
|
| 3248 |
if (ret < 0) { |
| 3249 |
goto fail;
|
| 3250 |
} |
| 3251 |
BLKDBG_EVENT(bs, BLKDBG_PWRITEV_RMW_AFTER_HEAD); |
| 3252 |
|
| 3253 |
qemu_iovec_init(&local_qiov, qiov->niov + 2);
|
| 3254 |
qemu_iovec_add(&local_qiov, head_buf, offset & (align - 1));
|
| 3255 |
qemu_iovec_concat(&local_qiov, qiov, 0, qiov->size);
|
| 3256 |
use_local_qiov = true;
|
| 3257 |
|
| 3258 |
bytes += offset & (align - 1);
|
| 3259 |
offset = offset & ~(align - 1);
|
| 3260 |
} |
| 3261 |
|
| 3262 |
if ((offset + bytes) & (align - 1)) { |
| 3263 |
QEMUIOVector tail_qiov; |
| 3264 |
struct iovec tail_iov;
|
| 3265 |
size_t tail_bytes; |
| 3266 |
bool waited;
|
| 3267 |
|
| 3268 |
mark_request_serialising(&req, align); |
| 3269 |
waited = wait_serialising_requests(&req); |
| 3270 |
assert(!waited || !use_local_qiov); |
| 3271 |
|
| 3272 |
tail_buf = qemu_blockalign(bs, align); |
| 3273 |
tail_iov = (struct iovec) {
|
| 3274 |
.iov_base = tail_buf, |
| 3275 |
.iov_len = align, |
| 3276 |
}; |
| 3277 |
qemu_iovec_init_external(&tail_qiov, &tail_iov, 1);
|
| 3278 |
|
| 3279 |
BLKDBG_EVENT(bs, BLKDBG_PWRITEV_RMW_TAIL); |
| 3280 |
ret = bdrv_aligned_preadv(bs, &req, (offset + bytes) & ~(align - 1), align,
|
| 3281 |
align, &tail_qiov, 0);
|
| 3282 |
if (ret < 0) { |
| 3283 |
goto fail;
|
| 3284 |
} |
| 3285 |
BLKDBG_EVENT(bs, BLKDBG_PWRITEV_RMW_AFTER_TAIL); |
| 3286 |
|
| 3287 |
if (!use_local_qiov) {
|
| 3288 |
qemu_iovec_init(&local_qiov, qiov->niov + 1);
|
| 3289 |
qemu_iovec_concat(&local_qiov, qiov, 0, qiov->size);
|
| 3290 |
use_local_qiov = true;
|
| 3291 |
} |
| 3292 |
|
| 3293 |
tail_bytes = (offset + bytes) & (align - 1);
|
| 3294 |
qemu_iovec_add(&local_qiov, tail_buf + tail_bytes, align - tail_bytes); |
| 3295 |
|
| 3296 |
bytes = ROUND_UP(bytes, align); |
| 3297 |
} |
| 3298 |
|
| 3299 |
ret = bdrv_aligned_pwritev(bs, &req, offset, bytes, |
| 3300 |
use_local_qiov ? &local_qiov : qiov, |
| 3301 |
flags); |
| 3302 |
|
| 3303 |
fail:
|
| 3304 |
tracked_request_end(&req); |
| 3305 |
|
| 3306 |
if (use_local_qiov) {
|
| 3307 |
qemu_iovec_destroy(&local_qiov); |
| 3308 |
} |
| 3309 |
qemu_vfree(head_buf); |
| 3310 |
qemu_vfree(tail_buf); |
| 3311 |
|
| 3312 |
return ret;
|
| 3313 |
} |
| 3314 |
|
| 3315 |
static int coroutine_fn bdrv_co_do_writev(BlockDriverState *bs, |
| 3316 |
int64_t sector_num, int nb_sectors, QEMUIOVector *qiov,
|
| 3317 |
BdrvRequestFlags flags) |
| 3318 |
{
|
| 3319 |
if (nb_sectors < 0 || nb_sectors > (INT_MAX >> BDRV_SECTOR_BITS)) { |
| 3320 |
return -EINVAL;
|
| 3321 |
} |
| 3322 |
|
| 3323 |
return bdrv_co_do_pwritev(bs, sector_num << BDRV_SECTOR_BITS,
|
| 3324 |
nb_sectors << BDRV_SECTOR_BITS, qiov, flags); |
| 3325 |
} |
| 3326 |
|
| 3327 |
int coroutine_fn bdrv_co_writev(BlockDriverState *bs, int64_t sector_num,
|
| 3328 |
int nb_sectors, QEMUIOVector *qiov)
|
| 3329 |
{
|
| 3330 |
trace_bdrv_co_writev(bs, sector_num, nb_sectors); |
| 3331 |
|
| 3332 |
return bdrv_co_do_writev(bs, sector_num, nb_sectors, qiov, 0); |
| 3333 |
} |
| 3334 |
|
| 3335 |
int coroutine_fn bdrv_co_write_zeroes(BlockDriverState *bs,
|
| 3336 |
int64_t sector_num, int nb_sectors,
|
| 3337 |
BdrvRequestFlags flags) |
| 3338 |
{
|
| 3339 |
trace_bdrv_co_write_zeroes(bs, sector_num, nb_sectors, flags); |
| 3340 |
|
| 3341 |
if (!(bs->open_flags & BDRV_O_UNMAP)) {
|
| 3342 |
flags &= ~BDRV_REQ_MAY_UNMAP; |
| 3343 |
} |
| 3344 |
|
| 3345 |
return bdrv_co_do_writev(bs, sector_num, nb_sectors, NULL, |
| 3346 |
BDRV_REQ_ZERO_WRITE | flags); |
| 3347 |
} |
| 3348 |
|
| 3349 |
/**
|
| 3350 |
* Truncate file to 'offset' bytes (needed only for file protocols)
|
| 3351 |
*/
|
| 3352 |
int bdrv_truncate(BlockDriverState *bs, int64_t offset)
|
| 3353 |
{
|
| 3354 |
BlockDriver *drv = bs->drv; |
| 3355 |
int ret;
|
| 3356 |
if (!drv)
|
| 3357 |
return -ENOMEDIUM;
|
| 3358 |
if (!drv->bdrv_truncate)
|
| 3359 |
return -ENOTSUP;
|
| 3360 |
if (bs->read_only)
|
| 3361 |
return -EACCES;
|
| 3362 |
if (bdrv_in_use(bs))
|
| 3363 |
return -EBUSY;
|
| 3364 |
ret = drv->bdrv_truncate(bs, offset); |
| 3365 |
if (ret == 0) { |
| 3366 |
ret = refresh_total_sectors(bs, offset >> BDRV_SECTOR_BITS); |
| 3367 |
bdrv_dev_resize_cb(bs); |
| 3368 |
} |
| 3369 |
return ret;
|
| 3370 |
} |
| 3371 |
|
| 3372 |
/**
|
| 3373 |
* Length of a allocated file in bytes. Sparse files are counted by actual
|
| 3374 |
* allocated space. Return < 0 if error or unknown.
|
| 3375 |
*/
|
| 3376 |
int64_t bdrv_get_allocated_file_size(BlockDriverState *bs) |
| 3377 |
{
|
| 3378 |
BlockDriver *drv = bs->drv; |
| 3379 |
if (!drv) {
|
| 3380 |
return -ENOMEDIUM;
|
| 3381 |
} |
| 3382 |
if (drv->bdrv_get_allocated_file_size) {
|
| 3383 |
return drv->bdrv_get_allocated_file_size(bs);
|
| 3384 |
} |
| 3385 |
if (bs->file) {
|
| 3386 |
return bdrv_get_allocated_file_size(bs->file);
|
| 3387 |
} |
| 3388 |
return -ENOTSUP;
|
| 3389 |
} |
| 3390 |
|
| 3391 |
/**
|
| 3392 |
* Length of a file in bytes. Return < 0 if error or unknown.
|
| 3393 |
*/
|
| 3394 |
int64_t bdrv_getlength(BlockDriverState *bs) |
| 3395 |
{
|
| 3396 |
BlockDriver *drv = bs->drv; |
| 3397 |
if (!drv)
|
| 3398 |
return -ENOMEDIUM;
|
| 3399 |
|
| 3400 |
if (drv->has_variable_length) {
|
| 3401 |
int ret = refresh_total_sectors(bs, bs->total_sectors);
|
| 3402 |
if (ret < 0) { |
| 3403 |
return ret;
|
| 3404 |
} |
| 3405 |
} |
| 3406 |
return bs->total_sectors * BDRV_SECTOR_SIZE;
|
| 3407 |
} |
| 3408 |
|
| 3409 |
/* return 0 as number of sectors if no device present or error */
|
| 3410 |
void bdrv_get_geometry(BlockDriverState *bs, uint64_t *nb_sectors_ptr)
|
| 3411 |
{
|
| 3412 |
int64_t length; |
| 3413 |
length = bdrv_getlength(bs); |
| 3414 |
if (length < 0) |
| 3415 |
length = 0;
|
| 3416 |
else
|
| 3417 |
length = length >> BDRV_SECTOR_BITS; |
| 3418 |
*nb_sectors_ptr = length; |
| 3419 |
} |
| 3420 |
|
| 3421 |
void bdrv_set_on_error(BlockDriverState *bs, BlockdevOnError on_read_error,
|
| 3422 |
BlockdevOnError on_write_error) |
| 3423 |
{
|
| 3424 |
bs->on_read_error = on_read_error; |
| 3425 |
bs->on_write_error = on_write_error; |
| 3426 |
} |
| 3427 |
|
| 3428 |
BlockdevOnError bdrv_get_on_error(BlockDriverState *bs, bool is_read)
|
| 3429 |
{
|
| 3430 |
return is_read ? bs->on_read_error : bs->on_write_error;
|
| 3431 |
} |
| 3432 |
|
| 3433 |
BlockErrorAction bdrv_get_error_action(BlockDriverState *bs, bool is_read, int error) |
| 3434 |
{
|
| 3435 |
BlockdevOnError on_err = is_read ? bs->on_read_error : bs->on_write_error; |
| 3436 |
|
| 3437 |
switch (on_err) {
|
| 3438 |
case BLOCKDEV_ON_ERROR_ENOSPC:
|
| 3439 |
return (error == ENOSPC) ? BDRV_ACTION_STOP : BDRV_ACTION_REPORT;
|
| 3440 |
case BLOCKDEV_ON_ERROR_STOP:
|
| 3441 |
return BDRV_ACTION_STOP;
|
| 3442 |
case BLOCKDEV_ON_ERROR_REPORT:
|
| 3443 |
return BDRV_ACTION_REPORT;
|
| 3444 |
case BLOCKDEV_ON_ERROR_IGNORE:
|
| 3445 |
return BDRV_ACTION_IGNORE;
|
| 3446 |
default:
|
| 3447 |
abort(); |
| 3448 |
} |
| 3449 |
} |
| 3450 |
|
| 3451 |
/* This is done by device models because, while the block layer knows
|
| 3452 |
* about the error, it does not know whether an operation comes from
|
| 3453 |
* the device or the block layer (from a job, for example).
|
| 3454 |
*/
|
| 3455 |
void bdrv_error_action(BlockDriverState *bs, BlockErrorAction action,
|
| 3456 |
bool is_read, int error) |
| 3457 |
{
|
| 3458 |
assert(error >= 0);
|
| 3459 |
bdrv_emit_qmp_error_event(bs, QEVENT_BLOCK_IO_ERROR, action, is_read); |
| 3460 |
if (action == BDRV_ACTION_STOP) {
|
| 3461 |
vm_stop(RUN_STATE_IO_ERROR); |
| 3462 |
bdrv_iostatus_set_err(bs, error); |
| 3463 |
} |
| 3464 |
} |
| 3465 |
|
| 3466 |
int bdrv_is_read_only(BlockDriverState *bs)
|
| 3467 |
{
|
| 3468 |
return bs->read_only;
|
| 3469 |
} |
| 3470 |
|
| 3471 |
int bdrv_is_sg(BlockDriverState *bs)
|
| 3472 |
{
|
| 3473 |
return bs->sg;
|
| 3474 |
} |
| 3475 |
|
| 3476 |
int bdrv_enable_write_cache(BlockDriverState *bs)
|
| 3477 |
{
|
| 3478 |
return bs->enable_write_cache;
|
| 3479 |
} |
| 3480 |
|
| 3481 |
void bdrv_set_enable_write_cache(BlockDriverState *bs, bool wce) |
| 3482 |
{
|
| 3483 |
bs->enable_write_cache = wce; |
| 3484 |
|
| 3485 |
/* so a reopen() will preserve wce */
|
| 3486 |
if (wce) {
|
| 3487 |
bs->open_flags |= BDRV_O_CACHE_WB; |
| 3488 |
} else {
|
| 3489 |
bs->open_flags &= ~BDRV_O_CACHE_WB; |
| 3490 |
} |
| 3491 |
} |
| 3492 |
|
| 3493 |
int bdrv_is_encrypted(BlockDriverState *bs)
|
| 3494 |
{
|
| 3495 |
if (bs->backing_hd && bs->backing_hd->encrypted)
|
| 3496 |
return 1; |
| 3497 |
return bs->encrypted;
|
| 3498 |
} |
| 3499 |
|
| 3500 |
int bdrv_key_required(BlockDriverState *bs)
|
| 3501 |
{
|
| 3502 |
BlockDriverState *backing_hd = bs->backing_hd; |
| 3503 |
|
| 3504 |
if (backing_hd && backing_hd->encrypted && !backing_hd->valid_key)
|
| 3505 |
return 1; |
| 3506 |
return (bs->encrypted && !bs->valid_key);
|
| 3507 |
} |
| 3508 |
|
| 3509 |
int bdrv_set_key(BlockDriverState *bs, const char *key) |
| 3510 |
{
|
| 3511 |
int ret;
|
| 3512 |
if (bs->backing_hd && bs->backing_hd->encrypted) {
|
| 3513 |
ret = bdrv_set_key(bs->backing_hd, key); |
| 3514 |
if (ret < 0) |
| 3515 |
return ret;
|
| 3516 |
if (!bs->encrypted)
|
| 3517 |
return 0; |
| 3518 |
} |
| 3519 |
if (!bs->encrypted) {
|
| 3520 |
return -EINVAL;
|
| 3521 |
} else if (!bs->drv || !bs->drv->bdrv_set_key) { |
| 3522 |
return -ENOMEDIUM;
|
| 3523 |
} |
| 3524 |
ret = bs->drv->bdrv_set_key(bs, key); |
| 3525 |
if (ret < 0) { |
| 3526 |
bs->valid_key = 0;
|
| 3527 |
} else if (!bs->valid_key) { |
| 3528 |
bs->valid_key = 1;
|
| 3529 |
/* call the change callback now, we skipped it on open */
|
| 3530 |
bdrv_dev_change_media_cb(bs, true);
|
| 3531 |
} |
| 3532 |
return ret;
|
| 3533 |
} |
| 3534 |
|
| 3535 |
const char *bdrv_get_format_name(BlockDriverState *bs) |
| 3536 |
{
|
| 3537 |
return bs->drv ? bs->drv->format_name : NULL; |
| 3538 |
} |
| 3539 |
|
| 3540 |
void bdrv_iterate_format(void (*it)(void *opaque, const char *name), |
| 3541 |
void *opaque)
|
| 3542 |
{
|
| 3543 |
BlockDriver *drv; |
| 3544 |
|
| 3545 |
QLIST_FOREACH(drv, &bdrv_drivers, list) {
|
| 3546 |
it(opaque, drv->format_name); |
| 3547 |
} |
| 3548 |
} |
| 3549 |
|
| 3550 |
/* This function is to find block backend bs */
|
| 3551 |
BlockDriverState *bdrv_find(const char *name) |
| 3552 |
{
|
| 3553 |
BlockDriverState *bs; |
| 3554 |
|
| 3555 |
QTAILQ_FOREACH(bs, &bdrv_states, device_list) {
|
| 3556 |
if (!strcmp(name, bs->device_name)) {
|
| 3557 |
return bs;
|
| 3558 |
} |
| 3559 |
} |
| 3560 |
return NULL; |
| 3561 |
} |
| 3562 |
|
| 3563 |
/* This function is to find a node in the bs graph */
|
| 3564 |
BlockDriverState *bdrv_find_node(const char *node_name) |
| 3565 |
{
|
| 3566 |
BlockDriverState *bs; |
| 3567 |
|
| 3568 |
assert(node_name); |
| 3569 |
|
| 3570 |
QTAILQ_FOREACH(bs, &graph_bdrv_states, node_list) {
|
| 3571 |
if (!strcmp(node_name, bs->node_name)) {
|
| 3572 |
return bs;
|
| 3573 |
} |
| 3574 |
} |
| 3575 |
return NULL; |
| 3576 |
} |
| 3577 |
|
| 3578 |
/* Put this QMP function here so it can access the static graph_bdrv_states. */
|
| 3579 |
BlockDeviceInfoList *bdrv_named_nodes_list(void)
|
| 3580 |
{
|
| 3581 |
BlockDeviceInfoList *list, *entry; |
| 3582 |
BlockDriverState *bs; |
| 3583 |
|
| 3584 |
list = NULL;
|
| 3585 |
QTAILQ_FOREACH(bs, &graph_bdrv_states, node_list) {
|
| 3586 |
entry = g_malloc0(sizeof(*entry));
|
| 3587 |
entry->value = bdrv_block_device_info(bs); |
| 3588 |
entry->next = list; |
| 3589 |
list = entry; |
| 3590 |
} |
| 3591 |
|
| 3592 |
return list;
|
| 3593 |
} |
| 3594 |
|
| 3595 |
BlockDriverState *bdrv_lookup_bs(const char *device, |
| 3596 |
const char *node_name, |
| 3597 |
Error **errp) |
| 3598 |
{
|
| 3599 |
BlockDriverState *bs = NULL;
|
| 3600 |
|
| 3601 |
if (device) {
|
| 3602 |
bs = bdrv_find(device); |
| 3603 |
|
| 3604 |
if (bs) {
|
| 3605 |
return bs;
|
| 3606 |
} |
| 3607 |
} |
| 3608 |
|
| 3609 |
if (node_name) {
|
| 3610 |
bs = bdrv_find_node(node_name); |
| 3611 |
|
| 3612 |
if (bs) {
|
| 3613 |
return bs;
|
| 3614 |
} |
| 3615 |
} |
| 3616 |
|
| 3617 |
error_setg(errp, "Cannot find device=%s nor node_name=%s",
|
| 3618 |
device ? device : "",
|
| 3619 |
node_name ? node_name : "");
|
| 3620 |
return NULL; |
| 3621 |
} |
| 3622 |
|
| 3623 |
BlockDriverState *bdrv_next(BlockDriverState *bs) |
| 3624 |
{
|
| 3625 |
if (!bs) {
|
| 3626 |
return QTAILQ_FIRST(&bdrv_states);
|
| 3627 |
} |
| 3628 |
return QTAILQ_NEXT(bs, device_list);
|
| 3629 |
} |
| 3630 |
|
| 3631 |
void bdrv_iterate(void (*it)(void *opaque, BlockDriverState *bs), void *opaque) |
| 3632 |
{
|
| 3633 |
BlockDriverState *bs; |
| 3634 |
|
| 3635 |
QTAILQ_FOREACH(bs, &bdrv_states, device_list) {
|
| 3636 |
it(opaque, bs); |
| 3637 |
} |
| 3638 |
} |
| 3639 |
|
| 3640 |
const char *bdrv_get_device_name(BlockDriverState *bs) |
| 3641 |
{
|
| 3642 |
return bs->device_name;
|
| 3643 |
} |
| 3644 |
|
| 3645 |
int bdrv_get_flags(BlockDriverState *bs)
|
| 3646 |
{
|
| 3647 |
return bs->open_flags;
|
| 3648 |
} |
| 3649 |
|
| 3650 |
int bdrv_flush_all(void) |
| 3651 |
{
|
| 3652 |
BlockDriverState *bs; |
| 3653 |
int result = 0; |
| 3654 |
|
| 3655 |
QTAILQ_FOREACH(bs, &bdrv_states, device_list) {
|
| 3656 |
int ret = bdrv_flush(bs);
|
| 3657 |
if (ret < 0 && !result) { |
| 3658 |
result = ret; |
| 3659 |
} |
| 3660 |
} |
| 3661 |
|
| 3662 |
return result;
|
| 3663 |
} |
| 3664 |
|
| 3665 |
int bdrv_has_zero_init_1(BlockDriverState *bs)
|
| 3666 |
{
|
| 3667 |
return 1; |
| 3668 |
} |
| 3669 |
|
| 3670 |
int bdrv_has_zero_init(BlockDriverState *bs)
|
| 3671 |
{
|
| 3672 |
assert(bs->drv); |
| 3673 |
|
| 3674 |
/* If BS is a copy on write image, it is initialized to
|
| 3675 |
the contents of the base image, which may not be zeroes. */
|
| 3676 |
if (bs->backing_hd) {
|
| 3677 |
return 0; |
| 3678 |
} |
| 3679 |
if (bs->drv->bdrv_has_zero_init) {
|
| 3680 |
return bs->drv->bdrv_has_zero_init(bs);
|
| 3681 |
} |
| 3682 |
|
| 3683 |
/* safe default */
|
| 3684 |
return 0; |
| 3685 |
} |
| 3686 |
|
| 3687 |
bool bdrv_unallocated_blocks_are_zero(BlockDriverState *bs)
|
| 3688 |
{
|
| 3689 |
BlockDriverInfo bdi; |
| 3690 |
|
| 3691 |
if (bs->backing_hd) {
|
| 3692 |
return false; |
| 3693 |
} |
| 3694 |
|
| 3695 |
if (bdrv_get_info(bs, &bdi) == 0) { |
| 3696 |
return bdi.unallocated_blocks_are_zero;
|
| 3697 |
} |
| 3698 |
|
| 3699 |
return false; |
| 3700 |
} |
| 3701 |
|
| 3702 |
bool bdrv_can_write_zeroes_with_unmap(BlockDriverState *bs)
|
| 3703 |
{
|
| 3704 |
BlockDriverInfo bdi; |
| 3705 |
|
| 3706 |
if (bs->backing_hd || !(bs->open_flags & BDRV_O_UNMAP)) {
|
| 3707 |
return false; |
| 3708 |
} |
| 3709 |
|
| 3710 |
if (bdrv_get_info(bs, &bdi) == 0) { |
| 3711 |
return bdi.can_write_zeroes_with_unmap;
|
| 3712 |
} |
| 3713 |
|
| 3714 |
return false; |
| 3715 |
} |
| 3716 |
|
| 3717 |
typedef struct BdrvCoGetBlockStatusData { |
| 3718 |
BlockDriverState *bs; |
| 3719 |
BlockDriverState *base; |
| 3720 |
int64_t sector_num; |
| 3721 |
int nb_sectors;
|
| 3722 |
int *pnum;
|
| 3723 |
int64_t ret; |
| 3724 |
bool done;
|
| 3725 |
} BdrvCoGetBlockStatusData; |
| 3726 |
|
| 3727 |
/*
|
| 3728 |
* Returns true iff the specified sector is present in the disk image. Drivers
|
| 3729 |
* not implementing the functionality are assumed to not support backing files,
|
| 3730 |
* hence all their sectors are reported as allocated.
|
| 3731 |
*
|
| 3732 |
* If 'sector_num' is beyond the end of the disk image the return value is 0
|
| 3733 |
* and 'pnum' is set to 0.
|
| 3734 |
*
|
| 3735 |
* 'pnum' is set to the number of sectors (including and immediately following
|
| 3736 |
* the specified sector) that are known to be in the same
|
| 3737 |
* allocated/unallocated state.
|
| 3738 |
*
|
| 3739 |
* 'nb_sectors' is the max value 'pnum' should be set to. If nb_sectors goes
|
| 3740 |
* beyond the end of the disk image it will be clamped.
|
| 3741 |
*/
|
| 3742 |
static int64_t coroutine_fn bdrv_co_get_block_status(BlockDriverState *bs,
|
| 3743 |
int64_t sector_num, |
| 3744 |
int nb_sectors, int *pnum) |
| 3745 |
{
|
| 3746 |
int64_t length; |
| 3747 |
int64_t n; |
| 3748 |
int64_t ret, ret2; |
| 3749 |
|
| 3750 |
length = bdrv_getlength(bs); |
| 3751 |
if (length < 0) { |
| 3752 |
return length;
|
| 3753 |
} |
| 3754 |
|
| 3755 |
if (sector_num >= (length >> BDRV_SECTOR_BITS)) {
|
| 3756 |
*pnum = 0;
|
| 3757 |
return 0; |
| 3758 |
} |
| 3759 |
|
| 3760 |
n = bs->total_sectors - sector_num; |
| 3761 |
if (n < nb_sectors) {
|
| 3762 |
nb_sectors = n; |
| 3763 |
} |
| 3764 |
|
| 3765 |
if (!bs->drv->bdrv_co_get_block_status) {
|
| 3766 |
*pnum = nb_sectors; |
| 3767 |
ret = BDRV_BLOCK_DATA; |
| 3768 |
if (bs->drv->protocol_name) {
|
| 3769 |
ret |= BDRV_BLOCK_OFFSET_VALID | (sector_num * BDRV_SECTOR_SIZE); |
| 3770 |
} |
| 3771 |
return ret;
|
| 3772 |
} |
| 3773 |
|
| 3774 |
ret = bs->drv->bdrv_co_get_block_status(bs, sector_num, nb_sectors, pnum); |
| 3775 |
if (ret < 0) { |
| 3776 |
*pnum = 0;
|
| 3777 |
return ret;
|
| 3778 |
} |
| 3779 |
|
| 3780 |
if (ret & BDRV_BLOCK_RAW) {
|
| 3781 |
assert(ret & BDRV_BLOCK_OFFSET_VALID); |
| 3782 |
return bdrv_get_block_status(bs->file, ret >> BDRV_SECTOR_BITS,
|
| 3783 |
*pnum, pnum); |
| 3784 |
} |
| 3785 |
|
| 3786 |
if (!(ret & BDRV_BLOCK_DATA) && !(ret & BDRV_BLOCK_ZERO)) {
|
| 3787 |
if (bdrv_unallocated_blocks_are_zero(bs)) {
|
| 3788 |
ret |= BDRV_BLOCK_ZERO; |
| 3789 |
} else if (bs->backing_hd) { |
| 3790 |
BlockDriverState *bs2 = bs->backing_hd; |
| 3791 |
int64_t length2 = bdrv_getlength(bs2); |
| 3792 |
if (length2 >= 0 && sector_num >= (length2 >> BDRV_SECTOR_BITS)) { |
| 3793 |
ret |= BDRV_BLOCK_ZERO; |
| 3794 |
} |
| 3795 |
} |
| 3796 |
} |
| 3797 |
|
| 3798 |
if (bs->file &&
|
| 3799 |
(ret & BDRV_BLOCK_DATA) && !(ret & BDRV_BLOCK_ZERO) && |
| 3800 |
(ret & BDRV_BLOCK_OFFSET_VALID)) {
|
| 3801 |
ret2 = bdrv_co_get_block_status(bs->file, ret >> BDRV_SECTOR_BITS, |
| 3802 |
*pnum, pnum); |
| 3803 |
if (ret2 >= 0) { |
| 3804 |
/* Ignore errors. This is just providing extra information, it
|
| 3805 |
* is useful but not necessary.
|
| 3806 |
*/
|
| 3807 |
ret |= (ret2 & BDRV_BLOCK_ZERO); |
| 3808 |
} |
| 3809 |
} |
| 3810 |
|
| 3811 |
return ret;
|
| 3812 |
} |
| 3813 |
|
| 3814 |
/* Coroutine wrapper for bdrv_get_block_status() */
|
| 3815 |
static void coroutine_fn bdrv_get_block_status_co_entry(void *opaque) |
| 3816 |
{
|
| 3817 |
BdrvCoGetBlockStatusData *data = opaque; |
| 3818 |
BlockDriverState *bs = data->bs; |
| 3819 |
|
| 3820 |
data->ret = bdrv_co_get_block_status(bs, data->sector_num, data->nb_sectors, |
| 3821 |
data->pnum); |
| 3822 |
data->done = true;
|
| 3823 |
} |
| 3824 |
|
| 3825 |
/*
|
| 3826 |
* Synchronous wrapper around bdrv_co_get_block_status().
|
| 3827 |
*
|
| 3828 |
* See bdrv_co_get_block_status() for details.
|
| 3829 |
*/
|
| 3830 |
int64_t bdrv_get_block_status(BlockDriverState *bs, int64_t sector_num, |
| 3831 |
int nb_sectors, int *pnum) |
| 3832 |
{
|
| 3833 |
Coroutine *co; |
| 3834 |
BdrvCoGetBlockStatusData data = {
|
| 3835 |
.bs = bs, |
| 3836 |
.sector_num = sector_num, |
| 3837 |
.nb_sectors = nb_sectors, |
| 3838 |
.pnum = pnum, |
| 3839 |
.done = false,
|
| 3840 |
}; |
| 3841 |
|
| 3842 |
if (qemu_in_coroutine()) {
|
| 3843 |
/* Fast-path if already in coroutine context */
|
| 3844 |
bdrv_get_block_status_co_entry(&data); |
| 3845 |
} else {
|
| 3846 |
co = qemu_coroutine_create(bdrv_get_block_status_co_entry); |
| 3847 |
qemu_coroutine_enter(co, &data); |
| 3848 |
while (!data.done) {
|
| 3849 |
qemu_aio_wait(); |
| 3850 |
} |
| 3851 |
} |
| 3852 |
return data.ret;
|
| 3853 |
} |
| 3854 |
|
| 3855 |
int coroutine_fn bdrv_is_allocated(BlockDriverState *bs, int64_t sector_num,
|
| 3856 |
int nb_sectors, int *pnum) |
| 3857 |
{
|
| 3858 |
int64_t ret = bdrv_get_block_status(bs, sector_num, nb_sectors, pnum); |
| 3859 |
if (ret < 0) { |
| 3860 |
return ret;
|
| 3861 |
} |
| 3862 |
return
|
| 3863 |
(ret & BDRV_BLOCK_DATA) || |
| 3864 |
((ret & BDRV_BLOCK_ZERO) && !bdrv_has_zero_init(bs)); |
| 3865 |
} |
| 3866 |
|
| 3867 |
/*
|
| 3868 |
* Given an image chain: ... -> [BASE] -> [INTER1] -> [INTER2] -> [TOP]
|
| 3869 |
*
|
| 3870 |
* Return true if the given sector is allocated in any image between
|
| 3871 |
* BASE and TOP (inclusive). BASE can be NULL to check if the given
|
| 3872 |
* sector is allocated in any image of the chain. Return false otherwise.
|
| 3873 |
*
|
| 3874 |
* 'pnum' is set to the number of sectors (including and immediately following
|
| 3875 |
* the specified sector) that are known to be in the same
|
| 3876 |
* allocated/unallocated state.
|
| 3877 |
*
|
| 3878 |
*/
|
| 3879 |
int bdrv_is_allocated_above(BlockDriverState *top,
|
| 3880 |
BlockDriverState *base, |
| 3881 |
int64_t sector_num, |
| 3882 |
int nb_sectors, int *pnum) |
| 3883 |
{
|
| 3884 |
BlockDriverState *intermediate; |
| 3885 |
int ret, n = nb_sectors;
|
| 3886 |
|
| 3887 |
intermediate = top; |
| 3888 |
while (intermediate && intermediate != base) {
|
| 3889 |
int pnum_inter;
|
| 3890 |
ret = bdrv_is_allocated(intermediate, sector_num, nb_sectors, |
| 3891 |
&pnum_inter); |
| 3892 |
if (ret < 0) { |
| 3893 |
return ret;
|
| 3894 |
} else if (ret) { |
| 3895 |
*pnum = pnum_inter; |
| 3896 |
return 1; |
| 3897 |
} |
| 3898 |
|
| 3899 |
/*
|
| 3900 |
* [sector_num, nb_sectors] is unallocated on top but intermediate
|
| 3901 |
* might have
|
| 3902 |
*
|
| 3903 |
* [sector_num+x, nr_sectors] allocated.
|
| 3904 |
*/
|
| 3905 |
if (n > pnum_inter &&
|
| 3906 |
(intermediate == top || |
| 3907 |
sector_num + pnum_inter < intermediate->total_sectors)) {
|
| 3908 |
n = pnum_inter; |
| 3909 |
} |
| 3910 |
|
| 3911 |
intermediate = intermediate->backing_hd; |
| 3912 |
} |
| 3913 |
|
| 3914 |
*pnum = n; |
| 3915 |
return 0; |
| 3916 |
} |
| 3917 |
|
| 3918 |
const char *bdrv_get_encrypted_filename(BlockDriverState *bs) |
| 3919 |
{
|
| 3920 |
if (bs->backing_hd && bs->backing_hd->encrypted)
|
| 3921 |
return bs->backing_file;
|
| 3922 |
else if (bs->encrypted) |
| 3923 |
return bs->filename;
|
| 3924 |
else
|
| 3925 |
return NULL; |
| 3926 |
} |
| 3927 |
|
| 3928 |
void bdrv_get_backing_filename(BlockDriverState *bs,
|
| 3929 |
char *filename, int filename_size) |
| 3930 |
{
|
| 3931 |
pstrcpy(filename, filename_size, bs->backing_file); |
| 3932 |
} |
| 3933 |
|
| 3934 |
int bdrv_write_compressed(BlockDriverState *bs, int64_t sector_num,
|
| 3935 |
const uint8_t *buf, int nb_sectors) |
| 3936 |
{
|
| 3937 |
BlockDriver *drv = bs->drv; |
| 3938 |
if (!drv)
|
| 3939 |
return -ENOMEDIUM;
|
| 3940 |
if (!drv->bdrv_write_compressed)
|
| 3941 |
return -ENOTSUP;
|
| 3942 |
if (bdrv_check_request(bs, sector_num, nb_sectors))
|
| 3943 |
return -EIO;
|
| 3944 |
|
| 3945 |
assert(QLIST_EMPTY(&bs->dirty_bitmaps)); |
| 3946 |
|
| 3947 |
return drv->bdrv_write_compressed(bs, sector_num, buf, nb_sectors);
|
| 3948 |
} |
| 3949 |
|
| 3950 |
int bdrv_get_info(BlockDriverState *bs, BlockDriverInfo *bdi)
|
| 3951 |
{
|
| 3952 |
BlockDriver *drv = bs->drv; |
| 3953 |
if (!drv)
|
| 3954 |
return -ENOMEDIUM;
|
| 3955 |
if (!drv->bdrv_get_info)
|
| 3956 |
return -ENOTSUP;
|
| 3957 |
memset(bdi, 0, sizeof(*bdi)); |
| 3958 |
return drv->bdrv_get_info(bs, bdi);
|
| 3959 |
} |
| 3960 |
|
| 3961 |
ImageInfoSpecific *bdrv_get_specific_info(BlockDriverState *bs) |
| 3962 |
{
|
| 3963 |
BlockDriver *drv = bs->drv; |
| 3964 |
if (drv && drv->bdrv_get_specific_info) {
|
| 3965 |
return drv->bdrv_get_specific_info(bs);
|
| 3966 |
} |
| 3967 |
return NULL; |
| 3968 |
} |
| 3969 |
|
| 3970 |
int bdrv_save_vmstate(BlockDriverState *bs, const uint8_t *buf, |
| 3971 |
int64_t pos, int size)
|
| 3972 |
{
|
| 3973 |
QEMUIOVector qiov; |
| 3974 |
struct iovec iov = {
|
| 3975 |
.iov_base = (void *) buf,
|
| 3976 |
.iov_len = size, |
| 3977 |
}; |
| 3978 |
|
| 3979 |
qemu_iovec_init_external(&qiov, &iov, 1);
|
| 3980 |
return bdrv_writev_vmstate(bs, &qiov, pos);
|
| 3981 |
} |
| 3982 |
|
| 3983 |
int bdrv_writev_vmstate(BlockDriverState *bs, QEMUIOVector *qiov, int64_t pos)
|
| 3984 |
{
|
| 3985 |
BlockDriver *drv = bs->drv; |
| 3986 |
|
| 3987 |
if (!drv) {
|
| 3988 |
return -ENOMEDIUM;
|
| 3989 |
} else if (drv->bdrv_save_vmstate) { |
| 3990 |
return drv->bdrv_save_vmstate(bs, qiov, pos);
|
| 3991 |
} else if (bs->file) { |
| 3992 |
return bdrv_writev_vmstate(bs->file, qiov, pos);
|
| 3993 |
} |
| 3994 |
|
| 3995 |
return -ENOTSUP;
|
| 3996 |
} |
| 3997 |
|
| 3998 |
int bdrv_load_vmstate(BlockDriverState *bs, uint8_t *buf,
|
| 3999 |
int64_t pos, int size)
|
| 4000 |
{
|
| 4001 |
BlockDriver *drv = bs->drv; |
| 4002 |
if (!drv)
|
| 4003 |
return -ENOMEDIUM;
|
| 4004 |
if (drv->bdrv_load_vmstate)
|
| 4005 |
return drv->bdrv_load_vmstate(bs, buf, pos, size);
|
| 4006 |
if (bs->file)
|
| 4007 |
return bdrv_load_vmstate(bs->file, buf, pos, size);
|
| 4008 |
return -ENOTSUP;
|
| 4009 |
} |
| 4010 |
|
| 4011 |
void bdrv_debug_event(BlockDriverState *bs, BlkDebugEvent event)
|
| 4012 |
{
|
| 4013 |
if (!bs || !bs->drv || !bs->drv->bdrv_debug_event) {
|
| 4014 |
return;
|
| 4015 |
} |
| 4016 |
|
| 4017 |
bs->drv->bdrv_debug_event(bs, event); |
| 4018 |
} |
| 4019 |
|
| 4020 |
int bdrv_debug_breakpoint(BlockDriverState *bs, const char *event, |
| 4021 |
const char *tag) |
| 4022 |
{
|
| 4023 |
while (bs && bs->drv && !bs->drv->bdrv_debug_breakpoint) {
|
| 4024 |
bs = bs->file; |
| 4025 |
} |
| 4026 |
|
| 4027 |
if (bs && bs->drv && bs->drv->bdrv_debug_breakpoint) {
|
| 4028 |
return bs->drv->bdrv_debug_breakpoint(bs, event, tag);
|
| 4029 |
} |
| 4030 |
|
| 4031 |
return -ENOTSUP;
|
| 4032 |
} |
| 4033 |
|
| 4034 |
int bdrv_debug_remove_breakpoint(BlockDriverState *bs, const char *tag) |
| 4035 |
{
|
| 4036 |
while (bs && bs->drv && !bs->drv->bdrv_debug_remove_breakpoint) {
|
| 4037 |
bs = bs->file; |
| 4038 |
} |
| 4039 |
|
| 4040 |
if (bs && bs->drv && bs->drv->bdrv_debug_remove_breakpoint) {
|
| 4041 |
return bs->drv->bdrv_debug_remove_breakpoint(bs, tag);
|
| 4042 |
} |
| 4043 |
|
| 4044 |
return -ENOTSUP;
|
| 4045 |
} |
| 4046 |
|
| 4047 |
int bdrv_debug_resume(BlockDriverState *bs, const char *tag) |
| 4048 |
{
|
| 4049 |
while (bs && bs->drv && !bs->drv->bdrv_debug_resume) {
|
| 4050 |
bs = bs->file; |
| 4051 |
} |
| 4052 |
|
| 4053 |
if (bs && bs->drv && bs->drv->bdrv_debug_resume) {
|
| 4054 |
return bs->drv->bdrv_debug_resume(bs, tag);
|
| 4055 |
} |
| 4056 |
|
| 4057 |
return -ENOTSUP;
|
| 4058 |
} |
| 4059 |
|
| 4060 |
bool bdrv_debug_is_suspended(BlockDriverState *bs, const char *tag) |
| 4061 |
{
|
| 4062 |
while (bs && bs->drv && !bs->drv->bdrv_debug_is_suspended) {
|
| 4063 |
bs = bs->file; |
| 4064 |
} |
| 4065 |
|
| 4066 |
if (bs && bs->drv && bs->drv->bdrv_debug_is_suspended) {
|
| 4067 |
return bs->drv->bdrv_debug_is_suspended(bs, tag);
|
| 4068 |
} |
| 4069 |
|
| 4070 |
return false; |
| 4071 |
} |
| 4072 |
|
| 4073 |
int bdrv_is_snapshot(BlockDriverState *bs)
|
| 4074 |
{
|
| 4075 |
return !!(bs->open_flags & BDRV_O_SNAPSHOT);
|
| 4076 |
} |
| 4077 |
|
| 4078 |
/* backing_file can either be relative, or absolute, or a protocol. If it is
|
| 4079 |
* relative, it must be relative to the chain. So, passing in bs->filename
|
| 4080 |
* from a BDS as backing_file should not be done, as that may be relative to
|
| 4081 |
* the CWD rather than the chain. */
|
| 4082 |
BlockDriverState *bdrv_find_backing_image(BlockDriverState *bs, |
| 4083 |
const char *backing_file) |
| 4084 |
{
|
| 4085 |
char *filename_full = NULL; |
| 4086 |
char *backing_file_full = NULL; |
| 4087 |
char *filename_tmp = NULL; |
| 4088 |
int is_protocol = 0; |
| 4089 |
BlockDriverState *curr_bs = NULL;
|
| 4090 |
BlockDriverState *retval = NULL;
|
| 4091 |
|
| 4092 |
if (!bs || !bs->drv || !backing_file) {
|
| 4093 |
return NULL; |
| 4094 |
} |
| 4095 |
|
| 4096 |
filename_full = g_malloc(PATH_MAX); |
| 4097 |
backing_file_full = g_malloc(PATH_MAX); |
| 4098 |
filename_tmp = g_malloc(PATH_MAX); |
| 4099 |
|
| 4100 |
is_protocol = path_has_protocol(backing_file); |
| 4101 |
|
| 4102 |
for (curr_bs = bs; curr_bs->backing_hd; curr_bs = curr_bs->backing_hd) {
|
| 4103 |
|
| 4104 |
/* If either of the filename paths is actually a protocol, then
|
| 4105 |
* compare unmodified paths; otherwise make paths relative */
|
| 4106 |
if (is_protocol || path_has_protocol(curr_bs->backing_file)) {
|
| 4107 |
if (strcmp(backing_file, curr_bs->backing_file) == 0) { |
| 4108 |
retval = curr_bs->backing_hd; |
| 4109 |
break;
|
| 4110 |
} |
| 4111 |
} else {
|
| 4112 |
/* If not an absolute filename path, make it relative to the current
|
| 4113 |
* image's filename path */
|
| 4114 |
path_combine(filename_tmp, PATH_MAX, curr_bs->filename, |
| 4115 |
backing_file); |
| 4116 |
|
| 4117 |
/* We are going to compare absolute pathnames */
|
| 4118 |
if (!realpath(filename_tmp, filename_full)) {
|
| 4119 |
continue;
|
| 4120 |
} |
| 4121 |
|
| 4122 |
/* We need to make sure the backing filename we are comparing against
|
| 4123 |
* is relative to the current image filename (or absolute) */
|
| 4124 |
path_combine(filename_tmp, PATH_MAX, curr_bs->filename, |
| 4125 |
curr_bs->backing_file); |
| 4126 |
|
| 4127 |
if (!realpath(filename_tmp, backing_file_full)) {
|
| 4128 |
continue;
|
| 4129 |
} |
| 4130 |
|
| 4131 |
if (strcmp(backing_file_full, filename_full) == 0) { |
| 4132 |
retval = curr_bs->backing_hd; |
| 4133 |
break;
|
| 4134 |
} |
| 4135 |
} |
| 4136 |
} |
| 4137 |
|
| 4138 |
g_free(filename_full); |
| 4139 |
g_free(backing_file_full); |
| 4140 |
g_free(filename_tmp); |
| 4141 |
return retval;
|
| 4142 |
} |
| 4143 |
|
| 4144 |
int bdrv_get_backing_file_depth(BlockDriverState *bs)
|
| 4145 |
{
|
| 4146 |
if (!bs->drv) {
|
| 4147 |
return 0; |
| 4148 |
} |
| 4149 |
|
| 4150 |
if (!bs->backing_hd) {
|
| 4151 |
return 0; |
| 4152 |
} |
| 4153 |
|
| 4154 |
return 1 + bdrv_get_backing_file_depth(bs->backing_hd); |
| 4155 |
} |
| 4156 |
|
| 4157 |
BlockDriverState *bdrv_find_base(BlockDriverState *bs) |
| 4158 |
{
|
| 4159 |
BlockDriverState *curr_bs = NULL;
|
| 4160 |
|
| 4161 |
if (!bs) {
|
| 4162 |
return NULL; |
| 4163 |
} |
| 4164 |
|
| 4165 |
curr_bs = bs; |
| 4166 |
|
| 4167 |
while (curr_bs->backing_hd) {
|
| 4168 |
curr_bs = curr_bs->backing_hd; |
| 4169 |
} |
| 4170 |
return curr_bs;
|
| 4171 |
} |
| 4172 |
|
| 4173 |
/**************************************************************/
|
| 4174 |
/* async I/Os */
|
| 4175 |
|
| 4176 |
BlockDriverAIOCB *bdrv_aio_readv(BlockDriverState *bs, int64_t sector_num, |
| 4177 |
QEMUIOVector *qiov, int nb_sectors,
|
| 4178 |
BlockDriverCompletionFunc *cb, void *opaque)
|
| 4179 |
{
|
| 4180 |
trace_bdrv_aio_readv(bs, sector_num, nb_sectors, opaque); |
| 4181 |
|
| 4182 |
return bdrv_co_aio_rw_vector(bs, sector_num, qiov, nb_sectors, 0, |
| 4183 |
cb, opaque, false);
|
| 4184 |
} |
| 4185 |
|
| 4186 |
BlockDriverAIOCB *bdrv_aio_writev(BlockDriverState *bs, int64_t sector_num, |
| 4187 |
QEMUIOVector *qiov, int nb_sectors,
|
| 4188 |
BlockDriverCompletionFunc *cb, void *opaque)
|
| 4189 |
{
|
| 4190 |
trace_bdrv_aio_writev(bs, sector_num, nb_sectors, opaque); |
| 4191 |
|
| 4192 |
return bdrv_co_aio_rw_vector(bs, sector_num, qiov, nb_sectors, 0, |
| 4193 |
cb, opaque, true);
|
| 4194 |
} |
| 4195 |
|
| 4196 |
BlockDriverAIOCB *bdrv_aio_write_zeroes(BlockDriverState *bs, |
| 4197 |
int64_t sector_num, int nb_sectors, BdrvRequestFlags flags,
|
| 4198 |
BlockDriverCompletionFunc *cb, void *opaque)
|
| 4199 |
{
|
| 4200 |
trace_bdrv_aio_write_zeroes(bs, sector_num, nb_sectors, flags, opaque); |
| 4201 |
|
| 4202 |
return bdrv_co_aio_rw_vector(bs, sector_num, NULL, nb_sectors, |
| 4203 |
BDRV_REQ_ZERO_WRITE | flags, |
| 4204 |
cb, opaque, true);
|
| 4205 |
} |
| 4206 |
|
| 4207 |
|
| 4208 |
typedef struct MultiwriteCB { |
| 4209 |
int error;
|
| 4210 |
int num_requests;
|
| 4211 |
int num_callbacks;
|
| 4212 |
struct {
|
| 4213 |
BlockDriverCompletionFunc *cb; |
| 4214 |
void *opaque;
|
| 4215 |
QEMUIOVector *free_qiov; |
| 4216 |
} callbacks[]; |
| 4217 |
} MultiwriteCB; |
| 4218 |
|
| 4219 |
static void multiwrite_user_cb(MultiwriteCB *mcb) |
| 4220 |
{
|
| 4221 |
int i;
|
| 4222 |
|
| 4223 |
for (i = 0; i < mcb->num_callbacks; i++) { |
| 4224 |
mcb->callbacks[i].cb(mcb->callbacks[i].opaque, mcb->error); |
| 4225 |
if (mcb->callbacks[i].free_qiov) {
|
| 4226 |
qemu_iovec_destroy(mcb->callbacks[i].free_qiov); |
| 4227 |
} |
| 4228 |
g_free(mcb->callbacks[i].free_qiov); |
| 4229 |
} |
| 4230 |
} |
| 4231 |
|
| 4232 |
static void multiwrite_cb(void *opaque, int ret) |
| 4233 |
{
|
| 4234 |
MultiwriteCB *mcb = opaque; |
| 4235 |
|
| 4236 |
trace_multiwrite_cb(mcb, ret); |
| 4237 |
|
| 4238 |
if (ret < 0 && !mcb->error) { |
| 4239 |
mcb->error = ret; |
| 4240 |
} |
| 4241 |
|
| 4242 |
mcb->num_requests--; |
| 4243 |
if (mcb->num_requests == 0) { |
| 4244 |
multiwrite_user_cb(mcb); |
| 4245 |
g_free(mcb); |
| 4246 |
} |
| 4247 |
} |
| 4248 |
|
| 4249 |
static int multiwrite_req_compare(const void *a, const void *b) |
| 4250 |
{
|
| 4251 |
const BlockRequest *req1 = a, *req2 = b;
|
| 4252 |
|
| 4253 |
/*
|
| 4254 |
* Note that we can't simply subtract req2->sector from req1->sector
|
| 4255 |
* here as that could overflow the return value.
|
| 4256 |
*/
|
| 4257 |
if (req1->sector > req2->sector) {
|
| 4258 |
return 1; |
| 4259 |
} else if (req1->sector < req2->sector) { |
| 4260 |
return -1; |
| 4261 |
} else {
|
| 4262 |
return 0; |
| 4263 |
} |
| 4264 |
} |
| 4265 |
|
| 4266 |
/*
|
| 4267 |
* Takes a bunch of requests and tries to merge them. Returns the number of
|
| 4268 |
* requests that remain after merging.
|
| 4269 |
*/
|
| 4270 |
static int multiwrite_merge(BlockDriverState *bs, BlockRequest *reqs, |
| 4271 |
int num_reqs, MultiwriteCB *mcb)
|
| 4272 |
{
|
| 4273 |
int i, outidx;
|
| 4274 |
|
| 4275 |
// Sort requests by start sector
|
| 4276 |
qsort(reqs, num_reqs, sizeof(*reqs), &multiwrite_req_compare);
|
| 4277 |
|
| 4278 |
// Check if adjacent requests touch the same clusters. If so, combine them,
|
| 4279 |
// filling up gaps with zero sectors.
|
| 4280 |
outidx = 0;
|
| 4281 |
for (i = 1; i < num_reqs; i++) { |
| 4282 |
int merge = 0; |
| 4283 |
int64_t oldreq_last = reqs[outidx].sector + reqs[outidx].nb_sectors; |
| 4284 |
|
| 4285 |
// Handle exactly sequential writes and overlapping writes.
|
| 4286 |
if (reqs[i].sector <= oldreq_last) {
|
| 4287 |
merge = 1;
|
| 4288 |
} |
| 4289 |
|
| 4290 |
if (reqs[outidx].qiov->niov + reqs[i].qiov->niov + 1 > IOV_MAX) { |
| 4291 |
merge = 0;
|
| 4292 |
} |
| 4293 |
|
| 4294 |
if (merge) {
|
| 4295 |
size_t size; |
| 4296 |
QEMUIOVector *qiov = g_malloc0(sizeof(*qiov));
|
| 4297 |
qemu_iovec_init(qiov, |
| 4298 |
reqs[outidx].qiov->niov + reqs[i].qiov->niov + 1);
|
| 4299 |
|
| 4300 |
// Add the first request to the merged one. If the requests are
|
| 4301 |
// overlapping, drop the last sectors of the first request.
|
| 4302 |
size = (reqs[i].sector - reqs[outidx].sector) << 9;
|
| 4303 |
qemu_iovec_concat(qiov, reqs[outidx].qiov, 0, size);
|
| 4304 |
|
| 4305 |
// We should need to add any zeros between the two requests
|
| 4306 |
assert (reqs[i].sector <= oldreq_last); |
| 4307 |
|
| 4308 |
// Add the second request
|
| 4309 |
qemu_iovec_concat(qiov, reqs[i].qiov, 0, reqs[i].qiov->size);
|
| 4310 |
|
| 4311 |
reqs[outidx].nb_sectors = qiov->size >> 9;
|
| 4312 |
reqs[outidx].qiov = qiov; |
| 4313 |
|
| 4314 |
mcb->callbacks[i].free_qiov = reqs[outidx].qiov; |
| 4315 |
} else {
|
| 4316 |
outidx++; |
| 4317 |
reqs[outidx].sector = reqs[i].sector; |
| 4318 |
reqs[outidx].nb_sectors = reqs[i].nb_sectors; |
| 4319 |
reqs[outidx].qiov = reqs[i].qiov; |
| 4320 |
} |
| 4321 |
} |
| 4322 |
|
| 4323 |
return outidx + 1; |
| 4324 |
} |
| 4325 |
|
| 4326 |
/*
|
| 4327 |
* Submit multiple AIO write requests at once.
|
| 4328 |
*
|
| 4329 |
* On success, the function returns 0 and all requests in the reqs array have
|
| 4330 |
* been submitted. In error case this function returns -1, and any of the
|
| 4331 |
* requests may or may not be submitted yet. In particular, this means that the
|
| 4332 |
* callback will be called for some of the requests, for others it won't. The
|
| 4333 |
* caller must check the error field of the BlockRequest to wait for the right
|
| 4334 |
* callbacks (if error != 0, no callback will be called).
|
| 4335 |
*
|
| 4336 |
* The implementation may modify the contents of the reqs array, e.g. to merge
|
| 4337 |
* requests. However, the fields opaque and error are left unmodified as they
|
| 4338 |
* are used to signal failure for a single request to the caller.
|
| 4339 |
*/
|
| 4340 |
int bdrv_aio_multiwrite(BlockDriverState *bs, BlockRequest *reqs, int num_reqs) |
| 4341 |
{
|
| 4342 |
MultiwriteCB *mcb; |
| 4343 |
int i;
|
| 4344 |
|
| 4345 |
/* don't submit writes if we don't have a medium */
|
| 4346 |
if (bs->drv == NULL) { |
| 4347 |
for (i = 0; i < num_reqs; i++) { |
| 4348 |
reqs[i].error = -ENOMEDIUM; |
| 4349 |
} |
| 4350 |
return -1; |
| 4351 |
} |
| 4352 |
|
| 4353 |
if (num_reqs == 0) { |
| 4354 |
return 0; |
| 4355 |
} |
| 4356 |
|
| 4357 |
// Create MultiwriteCB structure
|
| 4358 |
mcb = g_malloc0(sizeof(*mcb) + num_reqs * sizeof(*mcb->callbacks)); |
| 4359 |
mcb->num_requests = 0;
|
| 4360 |
mcb->num_callbacks = num_reqs; |
| 4361 |
|
| 4362 |
for (i = 0; i < num_reqs; i++) { |
| 4363 |
mcb->callbacks[i].cb = reqs[i].cb; |
| 4364 |
mcb->callbacks[i].opaque = reqs[i].opaque; |
| 4365 |
} |
| 4366 |
|
| 4367 |
// Check for mergable requests
|
| 4368 |
num_reqs = multiwrite_merge(bs, reqs, num_reqs, mcb); |
| 4369 |
|
| 4370 |
trace_bdrv_aio_multiwrite(mcb, mcb->num_callbacks, num_reqs); |
| 4371 |
|
| 4372 |
/* Run the aio requests. */
|
| 4373 |
mcb->num_requests = num_reqs; |
| 4374 |
for (i = 0; i < num_reqs; i++) { |
| 4375 |
bdrv_co_aio_rw_vector(bs, reqs[i].sector, reqs[i].qiov, |
| 4376 |
reqs[i].nb_sectors, reqs[i].flags, |
| 4377 |
multiwrite_cb, mcb, |
| 4378 |
true);
|
| 4379 |
} |
| 4380 |
|
| 4381 |
return 0; |
| 4382 |
} |
| 4383 |
|
| 4384 |
void bdrv_aio_cancel(BlockDriverAIOCB *acb)
|
| 4385 |
{
|
| 4386 |
acb->aiocb_info->cancel(acb); |
| 4387 |
} |
| 4388 |
|
| 4389 |
/**************************************************************/
|
| 4390 |
/* async block device emulation */
|
| 4391 |
|
| 4392 |
typedef struct BlockDriverAIOCBSync { |
| 4393 |
BlockDriverAIOCB common; |
| 4394 |
QEMUBH *bh; |
| 4395 |
int ret;
|
| 4396 |
/* vector translation state */
|
| 4397 |
QEMUIOVector *qiov; |
| 4398 |
uint8_t *bounce; |
| 4399 |
int is_write;
|
| 4400 |
} BlockDriverAIOCBSync; |
| 4401 |
|
| 4402 |
static void bdrv_aio_cancel_em(BlockDriverAIOCB *blockacb) |
| 4403 |
{
|
| 4404 |
BlockDriverAIOCBSync *acb = |
| 4405 |
container_of(blockacb, BlockDriverAIOCBSync, common); |
| 4406 |
qemu_bh_delete(acb->bh); |
| 4407 |
acb->bh = NULL;
|
| 4408 |
qemu_aio_release(acb); |
| 4409 |
} |
| 4410 |
|
| 4411 |
static const AIOCBInfo bdrv_em_aiocb_info = { |
| 4412 |
.aiocb_size = sizeof(BlockDriverAIOCBSync),
|
| 4413 |
.cancel = bdrv_aio_cancel_em, |
| 4414 |
}; |
| 4415 |
|
| 4416 |
static void bdrv_aio_bh_cb(void *opaque) |
| 4417 |
{
|
| 4418 |
BlockDriverAIOCBSync *acb = opaque; |
| 4419 |
|
| 4420 |
if (!acb->is_write)
|
| 4421 |
qemu_iovec_from_buf(acb->qiov, 0, acb->bounce, acb->qiov->size);
|
| 4422 |
qemu_vfree(acb->bounce); |
| 4423 |
acb->common.cb(acb->common.opaque, acb->ret); |
| 4424 |
qemu_bh_delete(acb->bh); |
| 4425 |
acb->bh = NULL;
|
| 4426 |
qemu_aio_release(acb); |
| 4427 |
} |
| 4428 |
|
| 4429 |
static BlockDriverAIOCB *bdrv_aio_rw_vector(BlockDriverState *bs,
|
| 4430 |
int64_t sector_num, |
| 4431 |
QEMUIOVector *qiov, |
| 4432 |
int nb_sectors,
|
| 4433 |
BlockDriverCompletionFunc *cb, |
| 4434 |
void *opaque,
|
| 4435 |
int is_write)
|
| 4436 |
|
| 4437 |
{
|
| 4438 |
BlockDriverAIOCBSync *acb; |
| 4439 |
|
| 4440 |
acb = qemu_aio_get(&bdrv_em_aiocb_info, bs, cb, opaque); |
| 4441 |
acb->is_write = is_write; |
| 4442 |
acb->qiov = qiov; |
| 4443 |
acb->bounce = qemu_blockalign(bs, qiov->size); |
| 4444 |
acb->bh = qemu_bh_new(bdrv_aio_bh_cb, acb); |
| 4445 |
|
| 4446 |
if (is_write) {
|
| 4447 |
qemu_iovec_to_buf(acb->qiov, 0, acb->bounce, qiov->size);
|
| 4448 |
acb->ret = bs->drv->bdrv_write(bs, sector_num, acb->bounce, nb_sectors); |
| 4449 |
} else {
|
| 4450 |
acb->ret = bs->drv->bdrv_read(bs, sector_num, acb->bounce, nb_sectors); |
| 4451 |
} |
| 4452 |
|
| 4453 |
qemu_bh_schedule(acb->bh); |
| 4454 |
|
| 4455 |
return &acb->common;
|
| 4456 |
} |
| 4457 |
|
| 4458 |
static BlockDriverAIOCB *bdrv_aio_readv_em(BlockDriverState *bs,
|
| 4459 |
int64_t sector_num, QEMUIOVector *qiov, int nb_sectors,
|
| 4460 |
BlockDriverCompletionFunc *cb, void *opaque)
|
| 4461 |
{
|
| 4462 |
return bdrv_aio_rw_vector(bs, sector_num, qiov, nb_sectors, cb, opaque, 0); |
| 4463 |
} |
| 4464 |
|
| 4465 |
static BlockDriverAIOCB *bdrv_aio_writev_em(BlockDriverState *bs,
|
| 4466 |
int64_t sector_num, QEMUIOVector *qiov, int nb_sectors,
|
| 4467 |
BlockDriverCompletionFunc *cb, void *opaque)
|
| 4468 |
{
|
| 4469 |
return bdrv_aio_rw_vector(bs, sector_num, qiov, nb_sectors, cb, opaque, 1); |
| 4470 |
} |
| 4471 |
|
| 4472 |
|
| 4473 |
typedef struct BlockDriverAIOCBCoroutine { |
| 4474 |
BlockDriverAIOCB common; |
| 4475 |
BlockRequest req; |
| 4476 |
bool is_write;
|
| 4477 |
bool *done;
|
| 4478 |
QEMUBH* bh; |
| 4479 |
} BlockDriverAIOCBCoroutine; |
| 4480 |
|
| 4481 |
static void bdrv_aio_co_cancel_em(BlockDriverAIOCB *blockacb) |
| 4482 |
{
|
| 4483 |
BlockDriverAIOCBCoroutine *acb = |
| 4484 |
container_of(blockacb, BlockDriverAIOCBCoroutine, common); |
| 4485 |
bool done = false; |
| 4486 |
|
| 4487 |
acb->done = &done; |
| 4488 |
while (!done) {
|
| 4489 |
qemu_aio_wait(); |
| 4490 |
} |
| 4491 |
} |
| 4492 |
|
| 4493 |
static const AIOCBInfo bdrv_em_co_aiocb_info = { |
| 4494 |
.aiocb_size = sizeof(BlockDriverAIOCBCoroutine),
|
| 4495 |
.cancel = bdrv_aio_co_cancel_em, |
| 4496 |
}; |
| 4497 |
|
| 4498 |
static void bdrv_co_em_bh(void *opaque) |
| 4499 |
{
|
| 4500 |
BlockDriverAIOCBCoroutine *acb = opaque; |
| 4501 |
|
| 4502 |
acb->common.cb(acb->common.opaque, acb->req.error); |
| 4503 |
|
| 4504 |
if (acb->done) {
|
| 4505 |
*acb->done = true;
|
| 4506 |
} |
| 4507 |
|
| 4508 |
qemu_bh_delete(acb->bh); |
| 4509 |
qemu_aio_release(acb); |
| 4510 |
} |
| 4511 |
|
| 4512 |
/* Invoke bdrv_co_do_readv/bdrv_co_do_writev */
|
| 4513 |
static void coroutine_fn bdrv_co_do_rw(void *opaque) |
| 4514 |
{
|
| 4515 |
BlockDriverAIOCBCoroutine *acb = opaque; |
| 4516 |
BlockDriverState *bs = acb->common.bs; |
| 4517 |
|
| 4518 |
if (!acb->is_write) {
|
| 4519 |
acb->req.error = bdrv_co_do_readv(bs, acb->req.sector, |
| 4520 |
acb->req.nb_sectors, acb->req.qiov, acb->req.flags); |
| 4521 |
} else {
|
| 4522 |
acb->req.error = bdrv_co_do_writev(bs, acb->req.sector, |
| 4523 |
acb->req.nb_sectors, acb->req.qiov, acb->req.flags); |
| 4524 |
} |
| 4525 |
|
| 4526 |
acb->bh = qemu_bh_new(bdrv_co_em_bh, acb); |
| 4527 |
qemu_bh_schedule(acb->bh); |
| 4528 |
} |
| 4529 |
|
| 4530 |
static BlockDriverAIOCB *bdrv_co_aio_rw_vector(BlockDriverState *bs,
|
| 4531 |
int64_t sector_num, |
| 4532 |
QEMUIOVector *qiov, |
| 4533 |
int nb_sectors,
|
| 4534 |
BdrvRequestFlags flags, |
| 4535 |
BlockDriverCompletionFunc *cb, |
| 4536 |
void *opaque,
|
| 4537 |
bool is_write)
|
| 4538 |
{
|
| 4539 |
Coroutine *co; |
| 4540 |
BlockDriverAIOCBCoroutine *acb; |
| 4541 |
|
| 4542 |
acb = qemu_aio_get(&bdrv_em_co_aiocb_info, bs, cb, opaque); |
| 4543 |
acb->req.sector = sector_num; |
| 4544 |
acb->req.nb_sectors = nb_sectors; |
| 4545 |
acb->req.qiov = qiov; |
| 4546 |
acb->req.flags = flags; |
| 4547 |
acb->is_write = is_write; |
| 4548 |
acb->done = NULL;
|
| 4549 |
|
| 4550 |
co = qemu_coroutine_create(bdrv_co_do_rw); |
| 4551 |
qemu_coroutine_enter(co, acb); |
| 4552 |
|
| 4553 |
return &acb->common;
|
| 4554 |
} |
| 4555 |
|
| 4556 |
static void coroutine_fn bdrv_aio_flush_co_entry(void *opaque) |
| 4557 |
{
|
| 4558 |
BlockDriverAIOCBCoroutine *acb = opaque; |
| 4559 |
BlockDriverState *bs = acb->common.bs; |
| 4560 |
|
| 4561 |
acb->req.error = bdrv_co_flush(bs); |
| 4562 |
acb->bh = qemu_bh_new(bdrv_co_em_bh, acb); |
| 4563 |
qemu_bh_schedule(acb->bh); |
| 4564 |
} |
| 4565 |
|
| 4566 |
BlockDriverAIOCB *bdrv_aio_flush(BlockDriverState *bs, |
| 4567 |
BlockDriverCompletionFunc *cb, void *opaque)
|
| 4568 |
{
|
| 4569 |
trace_bdrv_aio_flush(bs, opaque); |
| 4570 |
|
| 4571 |
Coroutine *co; |
| 4572 |
BlockDriverAIOCBCoroutine *acb; |
| 4573 |
|
| 4574 |
acb = qemu_aio_get(&bdrv_em_co_aiocb_info, bs, cb, opaque); |
| 4575 |
acb->done = NULL;
|
| 4576 |
|
| 4577 |
co = qemu_coroutine_create(bdrv_aio_flush_co_entry); |
| 4578 |
qemu_coroutine_enter(co, acb); |
| 4579 |
|
| 4580 |
return &acb->common;
|
| 4581 |
} |
| 4582 |
|
| 4583 |
static void coroutine_fn bdrv_aio_discard_co_entry(void *opaque) |
| 4584 |
{
|
| 4585 |
BlockDriverAIOCBCoroutine *acb = opaque; |
| 4586 |
BlockDriverState *bs = acb->common.bs; |
| 4587 |
|
| 4588 |
acb->req.error = bdrv_co_discard(bs, acb->req.sector, acb->req.nb_sectors); |
| 4589 |
acb->bh = qemu_bh_new(bdrv_co_em_bh, acb); |
| 4590 |
qemu_bh_schedule(acb->bh); |
| 4591 |
} |
| 4592 |
|
| 4593 |
BlockDriverAIOCB *bdrv_aio_discard(BlockDriverState *bs, |
| 4594 |
int64_t sector_num, int nb_sectors,
|
| 4595 |
BlockDriverCompletionFunc *cb, void *opaque)
|
| 4596 |
{
|
| 4597 |
Coroutine *co; |
| 4598 |
BlockDriverAIOCBCoroutine *acb; |
| 4599 |
|
| 4600 |
trace_bdrv_aio_discard(bs, sector_num, nb_sectors, opaque); |
| 4601 |
|
| 4602 |
acb = qemu_aio_get(&bdrv_em_co_aiocb_info, bs, cb, opaque); |
| 4603 |
acb->req.sector = sector_num; |
| 4604 |
acb->req.nb_sectors = nb_sectors; |
| 4605 |
acb->done = NULL;
|
| 4606 |
co = qemu_coroutine_create(bdrv_aio_discard_co_entry); |
| 4607 |
qemu_coroutine_enter(co, acb); |
| 4608 |
|
| 4609 |
return &acb->common;
|
| 4610 |
} |
| 4611 |
|
| 4612 |
void bdrv_init(void) |
| 4613 |
{
|
| 4614 |
module_call_init(MODULE_INIT_BLOCK); |
| 4615 |
} |
| 4616 |
|
| 4617 |
void bdrv_init_with_whitelist(void) |
| 4618 |
{
|
| 4619 |
use_bdrv_whitelist = 1;
|
| 4620 |
bdrv_init(); |
| 4621 |
} |
| 4622 |
|
| 4623 |
void *qemu_aio_get(const AIOCBInfo *aiocb_info, BlockDriverState *bs, |
| 4624 |
BlockDriverCompletionFunc *cb, void *opaque)
|
| 4625 |
{
|
| 4626 |
BlockDriverAIOCB *acb; |
| 4627 |
|
| 4628 |
acb = g_slice_alloc(aiocb_info->aiocb_size); |
| 4629 |
acb->aiocb_info = aiocb_info; |
| 4630 |
acb->bs = bs; |
| 4631 |
acb->cb = cb; |
| 4632 |
acb->opaque = opaque; |
| 4633 |
return acb;
|
| 4634 |
} |
| 4635 |
|
| 4636 |
void qemu_aio_release(void *p) |
| 4637 |
{
|
| 4638 |
BlockDriverAIOCB *acb = p; |
| 4639 |
g_slice_free1(acb->aiocb_info->aiocb_size, acb); |
| 4640 |
} |
| 4641 |
|
| 4642 |
/**************************************************************/
|
| 4643 |
/* Coroutine block device emulation */
|
| 4644 |
|
| 4645 |
typedef struct CoroutineIOCompletion { |
| 4646 |
Coroutine *coroutine; |
| 4647 |
int ret;
|
| 4648 |
} CoroutineIOCompletion; |
| 4649 |
|
| 4650 |
static void bdrv_co_io_em_complete(void *opaque, int ret) |
| 4651 |
{
|
| 4652 |
CoroutineIOCompletion *co = opaque; |
| 4653 |
|
| 4654 |
co->ret = ret; |
| 4655 |
qemu_coroutine_enter(co->coroutine, NULL);
|
| 4656 |
} |
| 4657 |
|
| 4658 |
static int coroutine_fn bdrv_co_io_em(BlockDriverState *bs, int64_t sector_num, |
| 4659 |
int nb_sectors, QEMUIOVector *iov,
|
| 4660 |
bool is_write)
|
| 4661 |
{
|
| 4662 |
CoroutineIOCompletion co = {
|
| 4663 |
.coroutine = qemu_coroutine_self(), |
| 4664 |
}; |
| 4665 |
BlockDriverAIOCB *acb; |
| 4666 |
|
| 4667 |
if (is_write) {
|
| 4668 |
acb = bs->drv->bdrv_aio_writev(bs, sector_num, iov, nb_sectors, |
| 4669 |
bdrv_co_io_em_complete, &co); |
| 4670 |
} else {
|
| 4671 |
acb = bs->drv->bdrv_aio_readv(bs, sector_num, iov, nb_sectors, |
| 4672 |
bdrv_co_io_em_complete, &co); |
| 4673 |
} |
| 4674 |
|
| 4675 |
trace_bdrv_co_io_em(bs, sector_num, nb_sectors, is_write, acb); |
| 4676 |
if (!acb) {
|
| 4677 |
return -EIO;
|
| 4678 |
} |
| 4679 |
qemu_coroutine_yield(); |
| 4680 |
|
| 4681 |
return co.ret;
|
| 4682 |
} |
| 4683 |
|
| 4684 |
static int coroutine_fn bdrv_co_readv_em(BlockDriverState *bs, |
| 4685 |
int64_t sector_num, int nb_sectors,
|
| 4686 |
QEMUIOVector *iov) |
| 4687 |
{
|
| 4688 |
return bdrv_co_io_em(bs, sector_num, nb_sectors, iov, false); |
| 4689 |
} |
| 4690 |
|
| 4691 |
static int coroutine_fn bdrv_co_writev_em(BlockDriverState *bs, |
| 4692 |
int64_t sector_num, int nb_sectors,
|
| 4693 |
QEMUIOVector *iov) |
| 4694 |
{
|
| 4695 |
return bdrv_co_io_em(bs, sector_num, nb_sectors, iov, true); |
| 4696 |
} |
| 4697 |
|
| 4698 |
static void coroutine_fn bdrv_flush_co_entry(void *opaque) |
| 4699 |
{
|
| 4700 |
RwCo *rwco = opaque; |
| 4701 |
|
| 4702 |
rwco->ret = bdrv_co_flush(rwco->bs); |
| 4703 |
} |
| 4704 |
|
| 4705 |
int coroutine_fn bdrv_co_flush(BlockDriverState *bs)
|
| 4706 |
{
|
| 4707 |
int ret;
|
| 4708 |
|
| 4709 |
if (!bs || !bdrv_is_inserted(bs) || bdrv_is_read_only(bs)) {
|
| 4710 |
return 0; |
| 4711 |
} |
| 4712 |
|
| 4713 |
/* Write back cached data to the OS even with cache=unsafe */
|
| 4714 |
BLKDBG_EVENT(bs->file, BLKDBG_FLUSH_TO_OS); |
| 4715 |
if (bs->drv->bdrv_co_flush_to_os) {
|
| 4716 |
ret = bs->drv->bdrv_co_flush_to_os(bs); |
| 4717 |
if (ret < 0) { |
| 4718 |
return ret;
|
| 4719 |
} |
| 4720 |
} |
| 4721 |
|
| 4722 |
/* But don't actually force it to the disk with cache=unsafe */
|
| 4723 |
if (bs->open_flags & BDRV_O_NO_FLUSH) {
|
| 4724 |
goto flush_parent;
|
| 4725 |
} |
| 4726 |
|
| 4727 |
BLKDBG_EVENT(bs->file, BLKDBG_FLUSH_TO_DISK); |
| 4728 |
if (bs->drv->bdrv_co_flush_to_disk) {
|
| 4729 |
ret = bs->drv->bdrv_co_flush_to_disk(bs); |
| 4730 |
} else if (bs->drv->bdrv_aio_flush) { |
| 4731 |
BlockDriverAIOCB *acb; |
| 4732 |
CoroutineIOCompletion co = {
|
| 4733 |
.coroutine = qemu_coroutine_self(), |
| 4734 |
}; |
| 4735 |
|
| 4736 |
acb = bs->drv->bdrv_aio_flush(bs, bdrv_co_io_em_complete, &co); |
| 4737 |
if (acb == NULL) { |
| 4738 |
ret = -EIO; |
| 4739 |
} else {
|
| 4740 |
qemu_coroutine_yield(); |
| 4741 |
ret = co.ret; |
| 4742 |
} |
| 4743 |
} else {
|
| 4744 |
/*
|
| 4745 |
* Some block drivers always operate in either writethrough or unsafe
|
| 4746 |
* mode and don't support bdrv_flush therefore. Usually qemu doesn't
|
| 4747 |
* know how the server works (because the behaviour is hardcoded or
|
| 4748 |
* depends on server-side configuration), so we can't ensure that
|
| 4749 |
* everything is safe on disk. Returning an error doesn't work because
|
| 4750 |
* that would break guests even if the server operates in writethrough
|
| 4751 |
* mode.
|
| 4752 |
*
|
| 4753 |
* Let's hope the user knows what he's doing.
|
| 4754 |
*/
|
| 4755 |
ret = 0;
|
| 4756 |
} |
| 4757 |
if (ret < 0) { |
| 4758 |
return ret;
|
| 4759 |
} |
| 4760 |
|
| 4761 |
/* Now flush the underlying protocol. It will also have BDRV_O_NO_FLUSH
|
| 4762 |
* in the case of cache=unsafe, so there are no useless flushes.
|
| 4763 |
*/
|
| 4764 |
flush_parent:
|
| 4765 |
return bdrv_co_flush(bs->file);
|
| 4766 |
} |
| 4767 |
|
| 4768 |
void bdrv_invalidate_cache(BlockDriverState *bs)
|
| 4769 |
{
|
| 4770 |
if (bs->drv && bs->drv->bdrv_invalidate_cache) {
|
| 4771 |
bs->drv->bdrv_invalidate_cache(bs); |
| 4772 |
} |
| 4773 |
} |
| 4774 |
|
| 4775 |
void bdrv_invalidate_cache_all(void) |
| 4776 |
{
|
| 4777 |
BlockDriverState *bs; |
| 4778 |
|
| 4779 |
QTAILQ_FOREACH(bs, &bdrv_states, device_list) {
|
| 4780 |
bdrv_invalidate_cache(bs); |
| 4781 |
} |
| 4782 |
} |
| 4783 |
|
| 4784 |
void bdrv_clear_incoming_migration_all(void) |
| 4785 |
{
|
| 4786 |
BlockDriverState *bs; |
| 4787 |
|
| 4788 |
QTAILQ_FOREACH(bs, &bdrv_states, device_list) {
|
| 4789 |
bs->open_flags = bs->open_flags & ~(BDRV_O_INCOMING); |
| 4790 |
} |
| 4791 |
} |
| 4792 |
|
| 4793 |
int bdrv_flush(BlockDriverState *bs)
|
| 4794 |
{
|
| 4795 |
Coroutine *co; |
| 4796 |
RwCo rwco = {
|
| 4797 |
.bs = bs, |
| 4798 |
.ret = NOT_DONE, |
| 4799 |
}; |
| 4800 |
|
| 4801 |
if (qemu_in_coroutine()) {
|
| 4802 |
/* Fast-path if already in coroutine context */
|
| 4803 |
bdrv_flush_co_entry(&rwco); |
| 4804 |
} else {
|
| 4805 |
co = qemu_coroutine_create(bdrv_flush_co_entry); |
| 4806 |
qemu_coroutine_enter(co, &rwco); |
| 4807 |
while (rwco.ret == NOT_DONE) {
|
| 4808 |
qemu_aio_wait(); |
| 4809 |
} |
| 4810 |
} |
| 4811 |
|
| 4812 |
return rwco.ret;
|
| 4813 |
} |
| 4814 |
|
| 4815 |
typedef struct DiscardCo { |
| 4816 |
BlockDriverState *bs; |
| 4817 |
int64_t sector_num; |
| 4818 |
int nb_sectors;
|
| 4819 |
int ret;
|
| 4820 |
} DiscardCo; |
| 4821 |
static void coroutine_fn bdrv_discard_co_entry(void *opaque) |
| 4822 |
{
|
| 4823 |
DiscardCo *rwco = opaque; |
| 4824 |
|
| 4825 |
rwco->ret = bdrv_co_discard(rwco->bs, rwco->sector_num, rwco->nb_sectors); |
| 4826 |
} |
| 4827 |
|
| 4828 |
/* if no limit is specified in the BlockLimits use a default
|
| 4829 |
* of 32768 512-byte sectors (16 MiB) per request.
|
| 4830 |
*/
|
| 4831 |
#define MAX_DISCARD_DEFAULT 32768 |
| 4832 |
|
| 4833 |
int coroutine_fn bdrv_co_discard(BlockDriverState *bs, int64_t sector_num,
|
| 4834 |
int nb_sectors)
|
| 4835 |
{
|
| 4836 |
int max_discard;
|
| 4837 |
|
| 4838 |
if (!bs->drv) {
|
| 4839 |
return -ENOMEDIUM;
|
| 4840 |
} else if (bdrv_check_request(bs, sector_num, nb_sectors)) { |
| 4841 |
return -EIO;
|
| 4842 |
} else if (bs->read_only) { |
| 4843 |
return -EROFS;
|
| 4844 |
} |
| 4845 |
|
| 4846 |
bdrv_reset_dirty(bs, sector_num, nb_sectors); |
| 4847 |
|
| 4848 |
/* Do nothing if disabled. */
|
| 4849 |
if (!(bs->open_flags & BDRV_O_UNMAP)) {
|
| 4850 |
return 0; |
| 4851 |
} |
| 4852 |
|
| 4853 |
if (!bs->drv->bdrv_co_discard && !bs->drv->bdrv_aio_discard) {
|
| 4854 |
return 0; |
| 4855 |
} |
| 4856 |
|
| 4857 |
max_discard = bs->bl.max_discard ? bs->bl.max_discard : MAX_DISCARD_DEFAULT; |
| 4858 |
while (nb_sectors > 0) { |
| 4859 |
int ret;
|
| 4860 |
int num = nb_sectors;
|
| 4861 |
|
| 4862 |
/* align request */
|
| 4863 |
if (bs->bl.discard_alignment &&
|
| 4864 |
num >= bs->bl.discard_alignment && |
| 4865 |
sector_num % bs->bl.discard_alignment) {
|
| 4866 |
if (num > bs->bl.discard_alignment) {
|
| 4867 |
num = bs->bl.discard_alignment; |
| 4868 |
} |
| 4869 |
num -= sector_num % bs->bl.discard_alignment; |
| 4870 |
} |
| 4871 |
|
| 4872 |
/* limit request size */
|
| 4873 |
if (num > max_discard) {
|
| 4874 |
num = max_discard; |
| 4875 |
} |
| 4876 |
|
| 4877 |
if (bs->drv->bdrv_co_discard) {
|
| 4878 |
ret = bs->drv->bdrv_co_discard(bs, sector_num, num); |
| 4879 |
} else {
|
| 4880 |
BlockDriverAIOCB *acb; |
| 4881 |
CoroutineIOCompletion co = {
|
| 4882 |
.coroutine = qemu_coroutine_self(), |
| 4883 |
}; |
| 4884 |
|
| 4885 |
acb = bs->drv->bdrv_aio_discard(bs, sector_num, nb_sectors, |
| 4886 |
bdrv_co_io_em_complete, &co); |
| 4887 |
if (acb == NULL) { |
| 4888 |
return -EIO;
|
| 4889 |
} else {
|
| 4890 |
qemu_coroutine_yield(); |
| 4891 |
ret = co.ret; |
| 4892 |
} |
| 4893 |
} |
| 4894 |
if (ret && ret != -ENOTSUP) {
|
| 4895 |
return ret;
|
| 4896 |
} |
| 4897 |
|
| 4898 |
sector_num += num; |
| 4899 |
nb_sectors -= num; |
| 4900 |
} |
| 4901 |
return 0; |
| 4902 |
} |
| 4903 |
|
| 4904 |
int bdrv_discard(BlockDriverState *bs, int64_t sector_num, int nb_sectors) |
| 4905 |
{
|
| 4906 |
Coroutine *co; |
| 4907 |
DiscardCo rwco = {
|
| 4908 |
.bs = bs, |
| 4909 |
.sector_num = sector_num, |
| 4910 |
.nb_sectors = nb_sectors, |
| 4911 |
.ret = NOT_DONE, |
| 4912 |
}; |
| 4913 |
|
| 4914 |
if (qemu_in_coroutine()) {
|
| 4915 |
/* Fast-path if already in coroutine context */
|
| 4916 |
bdrv_discard_co_entry(&rwco); |
| 4917 |
} else {
|
| 4918 |
co = qemu_coroutine_create(bdrv_discard_co_entry); |
| 4919 |
qemu_coroutine_enter(co, &rwco); |
| 4920 |
while (rwco.ret == NOT_DONE) {
|
| 4921 |
qemu_aio_wait(); |
| 4922 |
} |
| 4923 |
} |
| 4924 |
|
| 4925 |
return rwco.ret;
|
| 4926 |
} |
| 4927 |
|
| 4928 |
/**************************************************************/
|
| 4929 |
/* removable device support */
|
| 4930 |
|
| 4931 |
/**
|
| 4932 |
* Return TRUE if the media is present
|
| 4933 |
*/
|
| 4934 |
int bdrv_is_inserted(BlockDriverState *bs)
|
| 4935 |
{
|
| 4936 |
BlockDriver *drv = bs->drv; |
| 4937 |
|
| 4938 |
if (!drv)
|
| 4939 |
return 0; |
| 4940 |
if (!drv->bdrv_is_inserted)
|
| 4941 |
return 1; |
| 4942 |
return drv->bdrv_is_inserted(bs);
|
| 4943 |
} |
| 4944 |
|
| 4945 |
/**
|
| 4946 |
* Return whether the media changed since the last call to this
|
| 4947 |
* function, or -ENOTSUP if we don't know. Most drivers don't know.
|
| 4948 |
*/
|
| 4949 |
int bdrv_media_changed(BlockDriverState *bs)
|
| 4950 |
{
|
| 4951 |
BlockDriver *drv = bs->drv; |
| 4952 |
|
| 4953 |
if (drv && drv->bdrv_media_changed) {
|
| 4954 |
return drv->bdrv_media_changed(bs);
|
| 4955 |
} |
| 4956 |
return -ENOTSUP;
|
| 4957 |
} |
| 4958 |
|
| 4959 |
/**
|
| 4960 |
* If eject_flag is TRUE, eject the media. Otherwise, close the tray
|
| 4961 |
*/
|
| 4962 |
void bdrv_eject(BlockDriverState *bs, bool eject_flag) |
| 4963 |
{
|
| 4964 |
BlockDriver *drv = bs->drv; |
| 4965 |
|
| 4966 |
if (drv && drv->bdrv_eject) {
|
| 4967 |
drv->bdrv_eject(bs, eject_flag); |
| 4968 |
} |
| 4969 |
|
| 4970 |
if (bs->device_name[0] != '\0') { |
| 4971 |
bdrv_emit_qmp_eject_event(bs, eject_flag); |
| 4972 |
} |
| 4973 |
} |
| 4974 |
|
| 4975 |
/**
|
| 4976 |
* Lock or unlock the media (if it is locked, the user won't be able
|
| 4977 |
* to eject it manually).
|
| 4978 |
*/
|
| 4979 |
void bdrv_lock_medium(BlockDriverState *bs, bool locked) |
| 4980 |
{
|
| 4981 |
BlockDriver *drv = bs->drv; |
| 4982 |
|
| 4983 |
trace_bdrv_lock_medium(bs, locked); |
| 4984 |
|
| 4985 |
if (drv && drv->bdrv_lock_medium) {
|
| 4986 |
drv->bdrv_lock_medium(bs, locked); |
| 4987 |
} |
| 4988 |
} |
| 4989 |
|
| 4990 |
/* needed for generic scsi interface */
|
| 4991 |
|
| 4992 |
int bdrv_ioctl(BlockDriverState *bs, unsigned long int req, void *buf) |
| 4993 |
{
|
| 4994 |
BlockDriver *drv = bs->drv; |
| 4995 |
|
| 4996 |
if (drv && drv->bdrv_ioctl)
|
| 4997 |
return drv->bdrv_ioctl(bs, req, buf);
|
| 4998 |
return -ENOTSUP;
|
| 4999 |
} |
| 5000 |
|
| 5001 |
BlockDriverAIOCB *bdrv_aio_ioctl(BlockDriverState *bs, |
| 5002 |
unsigned long int req, void *buf, |
| 5003 |
BlockDriverCompletionFunc *cb, void *opaque)
|
| 5004 |
{
|
| 5005 |
BlockDriver *drv = bs->drv; |
| 5006 |
|
| 5007 |
if (drv && drv->bdrv_aio_ioctl)
|
| 5008 |
return drv->bdrv_aio_ioctl(bs, req, buf, cb, opaque);
|
| 5009 |
return NULL; |
| 5010 |
} |
| 5011 |
|
| 5012 |
void bdrv_set_guest_block_size(BlockDriverState *bs, int align) |
| 5013 |
{
|
| 5014 |
bs->guest_block_size = align; |
| 5015 |
} |
| 5016 |
|
| 5017 |
void *qemu_blockalign(BlockDriverState *bs, size_t size)
|
| 5018 |
{
|
| 5019 |
return qemu_memalign(bdrv_opt_mem_align(bs), size);
|
| 5020 |
} |
| 5021 |
|
| 5022 |
/*
|
| 5023 |
* Check if all memory in this vector is sector aligned.
|
| 5024 |
*/
|
| 5025 |
bool bdrv_qiov_is_aligned(BlockDriverState *bs, QEMUIOVector *qiov)
|
| 5026 |
{
|
| 5027 |
int i;
|
| 5028 |
size_t alignment = bdrv_opt_mem_align(bs); |
| 5029 |
|
| 5030 |
for (i = 0; i < qiov->niov; i++) { |
| 5031 |
if ((uintptr_t) qiov->iov[i].iov_base % alignment) {
|
| 5032 |
return false; |
| 5033 |
} |
| 5034 |
if (qiov->iov[i].iov_len % alignment) {
|
| 5035 |
return false; |
| 5036 |
} |
| 5037 |
} |
| 5038 |
|
| 5039 |
return true; |
| 5040 |
} |
| 5041 |
|
| 5042 |
BdrvDirtyBitmap *bdrv_create_dirty_bitmap(BlockDriverState *bs, int granularity)
|
| 5043 |
{
|
| 5044 |
int64_t bitmap_size; |
| 5045 |
BdrvDirtyBitmap *bitmap; |
| 5046 |
|
| 5047 |
assert((granularity & (granularity - 1)) == 0); |
| 5048 |
|
| 5049 |
granularity >>= BDRV_SECTOR_BITS; |
| 5050 |
assert(granularity); |
| 5051 |
bitmap_size = (bdrv_getlength(bs) >> BDRV_SECTOR_BITS); |
| 5052 |
bitmap = g_malloc0(sizeof(BdrvDirtyBitmap));
|
| 5053 |
bitmap->bitmap = hbitmap_alloc(bitmap_size, ffs(granularity) - 1);
|
| 5054 |
QLIST_INSERT_HEAD(&bs->dirty_bitmaps, bitmap, list); |
| 5055 |
return bitmap;
|
| 5056 |
} |
| 5057 |
|
| 5058 |
void bdrv_release_dirty_bitmap(BlockDriverState *bs, BdrvDirtyBitmap *bitmap)
|
| 5059 |
{
|
| 5060 |
BdrvDirtyBitmap *bm, *next; |
| 5061 |
QLIST_FOREACH_SAFE(bm, &bs->dirty_bitmaps, list, next) {
|
| 5062 |
if (bm == bitmap) {
|
| 5063 |
QLIST_REMOVE(bitmap, list); |
| 5064 |
hbitmap_free(bitmap->bitmap); |
| 5065 |
g_free(bitmap); |
| 5066 |
return;
|
| 5067 |
} |
| 5068 |
} |
| 5069 |
} |
| 5070 |
|
| 5071 |
BlockDirtyInfoList *bdrv_query_dirty_bitmaps(BlockDriverState *bs) |
| 5072 |
{
|
| 5073 |
BdrvDirtyBitmap *bm; |
| 5074 |
BlockDirtyInfoList *list = NULL;
|
| 5075 |
BlockDirtyInfoList **plist = &list; |
| 5076 |
|
| 5077 |
QLIST_FOREACH(bm, &bs->dirty_bitmaps, list) {
|
| 5078 |
BlockDirtyInfo *info = g_malloc0(sizeof(BlockDirtyInfo));
|
| 5079 |
BlockDirtyInfoList *entry = g_malloc0(sizeof(BlockDirtyInfoList));
|
| 5080 |
info->count = bdrv_get_dirty_count(bs, bm); |
| 5081 |
info->granularity = |
| 5082 |
((int64_t) BDRV_SECTOR_SIZE << hbitmap_granularity(bm->bitmap)); |
| 5083 |
entry->value = info; |
| 5084 |
*plist = entry; |
| 5085 |
plist = &entry->next; |
| 5086 |
} |
| 5087 |
|
| 5088 |
return list;
|
| 5089 |
} |
| 5090 |
|
| 5091 |
int bdrv_get_dirty(BlockDriverState *bs, BdrvDirtyBitmap *bitmap, int64_t sector)
|
| 5092 |
{
|
| 5093 |
if (bitmap) {
|
| 5094 |
return hbitmap_get(bitmap->bitmap, sector);
|
| 5095 |
} else {
|
| 5096 |
return 0; |
| 5097 |
} |
| 5098 |
} |
| 5099 |
|
| 5100 |
void bdrv_dirty_iter_init(BlockDriverState *bs,
|
| 5101 |
BdrvDirtyBitmap *bitmap, HBitmapIter *hbi) |
| 5102 |
{
|
| 5103 |
hbitmap_iter_init(hbi, bitmap->bitmap, 0);
|
| 5104 |
} |
| 5105 |
|
| 5106 |
void bdrv_set_dirty(BlockDriverState *bs, int64_t cur_sector,
|
| 5107 |
int nr_sectors)
|
| 5108 |
{
|
| 5109 |
BdrvDirtyBitmap *bitmap; |
| 5110 |
QLIST_FOREACH(bitmap, &bs->dirty_bitmaps, list) {
|
| 5111 |
hbitmap_set(bitmap->bitmap, cur_sector, nr_sectors); |
| 5112 |
} |
| 5113 |
} |
| 5114 |
|
| 5115 |
void bdrv_reset_dirty(BlockDriverState *bs, int64_t cur_sector, int nr_sectors) |
| 5116 |
{
|
| 5117 |
BdrvDirtyBitmap *bitmap; |
| 5118 |
QLIST_FOREACH(bitmap, &bs->dirty_bitmaps, list) {
|
| 5119 |
hbitmap_reset(bitmap->bitmap, cur_sector, nr_sectors); |
| 5120 |
} |
| 5121 |
} |
| 5122 |
|
| 5123 |
int64_t bdrv_get_dirty_count(BlockDriverState *bs, BdrvDirtyBitmap *bitmap) |
| 5124 |
{
|
| 5125 |
return hbitmap_count(bitmap->bitmap);
|
| 5126 |
} |
| 5127 |
|
| 5128 |
/* Get a reference to bs */
|
| 5129 |
void bdrv_ref(BlockDriverState *bs)
|
| 5130 |
{
|
| 5131 |
bs->refcnt++; |
| 5132 |
} |
| 5133 |
|
| 5134 |
/* Release a previously grabbed reference to bs.
|
| 5135 |
* If after releasing, reference count is zero, the BlockDriverState is
|
| 5136 |
* deleted. */
|
| 5137 |
void bdrv_unref(BlockDriverState *bs)
|
| 5138 |
{
|
| 5139 |
assert(bs->refcnt > 0);
|
| 5140 |
if (--bs->refcnt == 0) { |
| 5141 |
bdrv_delete(bs); |
| 5142 |
} |
| 5143 |
} |
| 5144 |
|
| 5145 |
void bdrv_set_in_use(BlockDriverState *bs, int in_use) |
| 5146 |
{
|
| 5147 |
assert(bs->in_use != in_use); |
| 5148 |
bs->in_use = in_use; |
| 5149 |
} |
| 5150 |
|
| 5151 |
int bdrv_in_use(BlockDriverState *bs)
|
| 5152 |
{
|
| 5153 |
return bs->in_use;
|
| 5154 |
} |
| 5155 |
|
| 5156 |
void bdrv_iostatus_enable(BlockDriverState *bs)
|
| 5157 |
{
|
| 5158 |
bs->iostatus_enabled = true;
|
| 5159 |
bs->iostatus = BLOCK_DEVICE_IO_STATUS_OK; |
| 5160 |
} |
| 5161 |
|
| 5162 |
/* The I/O status is only enabled if the drive explicitly
|
| 5163 |
* enables it _and_ the VM is configured to stop on errors */
|
| 5164 |
bool bdrv_iostatus_is_enabled(const BlockDriverState *bs) |
| 5165 |
{
|
| 5166 |
return (bs->iostatus_enabled &&
|
| 5167 |
(bs->on_write_error == BLOCKDEV_ON_ERROR_ENOSPC || |
| 5168 |
bs->on_write_error == BLOCKDEV_ON_ERROR_STOP || |
| 5169 |
bs->on_read_error == BLOCKDEV_ON_ERROR_STOP)); |
| 5170 |
} |
| 5171 |
|
| 5172 |
void bdrv_iostatus_disable(BlockDriverState *bs)
|
| 5173 |
{
|
| 5174 |
bs->iostatus_enabled = false;
|
| 5175 |
} |
| 5176 |
|
| 5177 |
void bdrv_iostatus_reset(BlockDriverState *bs)
|
| 5178 |
{
|
| 5179 |
if (bdrv_iostatus_is_enabled(bs)) {
|
| 5180 |
bs->iostatus = BLOCK_DEVICE_IO_STATUS_OK; |
| 5181 |
if (bs->job) {
|
| 5182 |
block_job_iostatus_reset(bs->job); |
| 5183 |
} |
| 5184 |
} |
| 5185 |
} |
| 5186 |
|
| 5187 |
void bdrv_iostatus_set_err(BlockDriverState *bs, int error) |
| 5188 |
{
|
| 5189 |
assert(bdrv_iostatus_is_enabled(bs)); |
| 5190 |
if (bs->iostatus == BLOCK_DEVICE_IO_STATUS_OK) {
|
| 5191 |
bs->iostatus = error == ENOSPC ? BLOCK_DEVICE_IO_STATUS_NOSPACE : |
| 5192 |
BLOCK_DEVICE_IO_STATUS_FAILED; |
| 5193 |
} |
| 5194 |
} |
| 5195 |
|
| 5196 |
void
|
| 5197 |
bdrv_acct_start(BlockDriverState *bs, BlockAcctCookie *cookie, int64_t bytes, |
| 5198 |
enum BlockAcctType type)
|
| 5199 |
{
|
| 5200 |
assert(type < BDRV_MAX_IOTYPE); |
| 5201 |
|
| 5202 |
cookie->bytes = bytes; |
| 5203 |
cookie->start_time_ns = get_clock(); |
| 5204 |
cookie->type = type; |
| 5205 |
} |
| 5206 |
|
| 5207 |
void
|
| 5208 |
bdrv_acct_done(BlockDriverState *bs, BlockAcctCookie *cookie) |
| 5209 |
{
|
| 5210 |
assert(cookie->type < BDRV_MAX_IOTYPE); |
| 5211 |
|
| 5212 |
bs->nr_bytes[cookie->type] += cookie->bytes; |
| 5213 |
bs->nr_ops[cookie->type]++; |
| 5214 |
bs->total_time_ns[cookie->type] += get_clock() - cookie->start_time_ns; |
| 5215 |
} |
| 5216 |
|
| 5217 |
void bdrv_img_create(const char *filename, const char *fmt, |
| 5218 |
const char *base_filename, const char *base_fmt, |
| 5219 |
char *options, uint64_t img_size, int flags, |
| 5220 |
Error **errp, bool quiet)
|
| 5221 |
{
|
| 5222 |
QEMUOptionParameter *param = NULL, *create_options = NULL; |
| 5223 |
QEMUOptionParameter *backing_fmt, *backing_file, *size; |
| 5224 |
BlockDriver *drv, *proto_drv; |
| 5225 |
BlockDriver *backing_drv = NULL;
|
| 5226 |
Error *local_err = NULL;
|
| 5227 |
int ret = 0; |
| 5228 |
|
| 5229 |
/* Find driver and parse its options */
|
| 5230 |
drv = bdrv_find_format(fmt); |
| 5231 |
if (!drv) {
|
| 5232 |
error_setg(errp, "Unknown file format '%s'", fmt);
|
| 5233 |
return;
|
| 5234 |
} |
| 5235 |
|
| 5236 |
proto_drv = bdrv_find_protocol(filename, true);
|
| 5237 |
if (!proto_drv) {
|
| 5238 |
error_setg(errp, "Unknown protocol '%s'", filename);
|
| 5239 |
return;
|
| 5240 |
} |
| 5241 |
|
| 5242 |
create_options = append_option_parameters(create_options, |
| 5243 |
drv->create_options); |
| 5244 |
create_options = append_option_parameters(create_options, |
| 5245 |
proto_drv->create_options); |
| 5246 |
|
| 5247 |
/* Create parameter list with default values */
|
| 5248 |
param = parse_option_parameters("", create_options, param);
|
| 5249 |
|
| 5250 |
set_option_parameter_int(param, BLOCK_OPT_SIZE, img_size); |
| 5251 |
|
| 5252 |
/* Parse -o options */
|
| 5253 |
if (options) {
|
| 5254 |
param = parse_option_parameters(options, create_options, param); |
| 5255 |
if (param == NULL) { |
| 5256 |
error_setg(errp, "Invalid options for file format '%s'.", fmt);
|
| 5257 |
goto out;
|
| 5258 |
} |
| 5259 |
} |
| 5260 |
|
| 5261 |
if (base_filename) {
|
| 5262 |
if (set_option_parameter(param, BLOCK_OPT_BACKING_FILE,
|
| 5263 |
base_filename)) {
|
| 5264 |
error_setg(errp, "Backing file not supported for file format '%s'",
|
| 5265 |
fmt); |
| 5266 |
goto out;
|
| 5267 |
} |
| 5268 |
} |
| 5269 |
|
| 5270 |
if (base_fmt) {
|
| 5271 |
if (set_option_parameter(param, BLOCK_OPT_BACKING_FMT, base_fmt)) {
|
| 5272 |
error_setg(errp, "Backing file format not supported for file "
|
| 5273 |
"format '%s'", fmt);
|
| 5274 |
goto out;
|
| 5275 |
} |
| 5276 |
} |
| 5277 |
|
| 5278 |
backing_file = get_option_parameter(param, BLOCK_OPT_BACKING_FILE); |
| 5279 |
if (backing_file && backing_file->value.s) {
|
| 5280 |
if (!strcmp(filename, backing_file->value.s)) {
|
| 5281 |
error_setg(errp, "Error: Trying to create an image with the "
|
| 5282 |
"same filename as the backing file");
|
| 5283 |
goto out;
|
| 5284 |
} |
| 5285 |
} |
| 5286 |
|
| 5287 |
backing_fmt = get_option_parameter(param, BLOCK_OPT_BACKING_FMT); |
| 5288 |
if (backing_fmt && backing_fmt->value.s) {
|
| 5289 |
backing_drv = bdrv_find_format(backing_fmt->value.s); |
| 5290 |
if (!backing_drv) {
|
| 5291 |
error_setg(errp, "Unknown backing file format '%s'",
|
| 5292 |
backing_fmt->value.s); |
| 5293 |
goto out;
|
| 5294 |
} |
| 5295 |
} |
| 5296 |
|
| 5297 |
// The size for the image must always be specified, with one exception:
|
| 5298 |
// If we are using a backing file, we can obtain the size from there
|
| 5299 |
size = get_option_parameter(param, BLOCK_OPT_SIZE); |
| 5300 |
if (size && size->value.n == -1) { |
| 5301 |
if (backing_file && backing_file->value.s) {
|
| 5302 |
BlockDriverState *bs; |
| 5303 |
uint64_t size; |
| 5304 |
char buf[32]; |
| 5305 |
int back_flags;
|
| 5306 |
|
| 5307 |
/* backing files always opened read-only */
|
| 5308 |
back_flags = |
| 5309 |
flags & ~(BDRV_O_RDWR | BDRV_O_SNAPSHOT | BDRV_O_NO_BACKING); |
| 5310 |
|
| 5311 |
bs = NULL;
|
| 5312 |
ret = bdrv_open(&bs, backing_file->value.s, NULL, back_flags,
|
| 5313 |
backing_drv, &local_err); |
| 5314 |
if (ret < 0) { |
| 5315 |
error_setg_errno(errp, -ret, "Could not open '%s': %s",
|
| 5316 |
backing_file->value.s, |
| 5317 |
error_get_pretty(local_err)); |
| 5318 |
error_free(local_err); |
| 5319 |
local_err = NULL;
|
| 5320 |
goto out;
|
| 5321 |
} |
| 5322 |
bdrv_get_geometry(bs, &size); |
| 5323 |
size *= 512;
|
| 5324 |
|
| 5325 |
snprintf(buf, sizeof(buf), "%" PRId64, size); |
| 5326 |
set_option_parameter(param, BLOCK_OPT_SIZE, buf); |
| 5327 |
|
| 5328 |
bdrv_unref(bs); |
| 5329 |
} else {
|
| 5330 |
error_setg(errp, "Image creation needs a size parameter");
|
| 5331 |
goto out;
|
| 5332 |
} |
| 5333 |
} |
| 5334 |
|
| 5335 |
if (!quiet) {
|
| 5336 |
printf("Formatting '%s', fmt=%s ", filename, fmt);
|
| 5337 |
print_option_parameters(param); |
| 5338 |
puts("");
|
| 5339 |
} |
| 5340 |
ret = bdrv_create(drv, filename, param, &local_err); |
| 5341 |
if (ret == -EFBIG) {
|
| 5342 |
/* This is generally a better message than whatever the driver would
|
| 5343 |
* deliver (especially because of the cluster_size_hint), since that
|
| 5344 |
* is most probably not much different from "image too large". */
|
| 5345 |
const char *cluster_size_hint = ""; |
| 5346 |
if (get_option_parameter(create_options, BLOCK_OPT_CLUSTER_SIZE)) {
|
| 5347 |
cluster_size_hint = " (try using a larger cluster size)";
|
| 5348 |
} |
| 5349 |
error_setg(errp, "The image size is too large for file format '%s'"
|
| 5350 |
"%s", fmt, cluster_size_hint);
|
| 5351 |
error_free(local_err); |
| 5352 |
local_err = NULL;
|
| 5353 |
} |
| 5354 |
|
| 5355 |
out:
|
| 5356 |
free_option_parameters(create_options); |
| 5357 |
free_option_parameters(param); |
| 5358 |
|
| 5359 |
if (local_err) {
|
| 5360 |
error_propagate(errp, local_err); |
| 5361 |
} |
| 5362 |
} |
| 5363 |
|
| 5364 |
AioContext *bdrv_get_aio_context(BlockDriverState *bs) |
| 5365 |
{
|
| 5366 |
/* Currently BlockDriverState always uses the main loop AioContext */
|
| 5367 |
return qemu_get_aio_context();
|
| 5368 |
} |
| 5369 |
|
| 5370 |
void bdrv_add_before_write_notifier(BlockDriverState *bs,
|
| 5371 |
NotifierWithReturn *notifier) |
| 5372 |
{
|
| 5373 |
notifier_with_return_list_add(&bs->before_write_notifiers, notifier); |
| 5374 |
} |
| 5375 |
|
| 5376 |
int bdrv_amend_options(BlockDriverState *bs, QEMUOptionParameter *options)
|
| 5377 |
{
|
| 5378 |
if (bs->drv->bdrv_amend_options == NULL) { |
| 5379 |
return -ENOTSUP;
|
| 5380 |
} |
| 5381 |
return bs->drv->bdrv_amend_options(bs, options);
|
| 5382 |
} |
| 5383 |
|
| 5384 |
/* Used to recurse on single child block filters.
|
| 5385 |
* Single child block filter will store their child in bs->file.
|
| 5386 |
*/
|
| 5387 |
bool bdrv_generic_is_first_non_filter(BlockDriverState *bs,
|
| 5388 |
BlockDriverState *candidate) |
| 5389 |
{
|
| 5390 |
if (!bs->drv) {
|
| 5391 |
return false; |
| 5392 |
} |
| 5393 |
|
| 5394 |
if (!bs->drv->authorizations[BS_IS_A_FILTER]) {
|
| 5395 |
if (bs == candidate) {
|
| 5396 |
return true; |
| 5397 |
} else {
|
| 5398 |
return false; |
| 5399 |
} |
| 5400 |
} |
| 5401 |
|
| 5402 |
if (!bs->drv->authorizations[BS_FILTER_PASS_DOWN]) {
|
| 5403 |
return false; |
| 5404 |
} |
| 5405 |
|
| 5406 |
if (!bs->file) {
|
| 5407 |
return false; |
| 5408 |
} |
| 5409 |
|
| 5410 |
return bdrv_recurse_is_first_non_filter(bs->file, candidate);
|
| 5411 |
} |
| 5412 |
|
| 5413 |
bool bdrv_recurse_is_first_non_filter(BlockDriverState *bs,
|
| 5414 |
BlockDriverState *candidate) |
| 5415 |
{
|
| 5416 |
if (bs->drv && bs->drv->bdrv_recurse_is_first_non_filter) {
|
| 5417 |
return bs->drv->bdrv_recurse_is_first_non_filter(bs, candidate);
|
| 5418 |
} |
| 5419 |
|
| 5420 |
return bdrv_generic_is_first_non_filter(bs, candidate);
|
| 5421 |
} |
| 5422 |
|
| 5423 |
/* This function checks if the candidate is the first non filter bs down it's
|
| 5424 |
* bs chain. Since we don't have pointers to parents it explore all bs chains
|
| 5425 |
* from the top. Some filters can choose not to pass down the recursion.
|
| 5426 |
*/
|
| 5427 |
bool bdrv_is_first_non_filter(BlockDriverState *candidate)
|
| 5428 |
{
|
| 5429 |
BlockDriverState *bs; |
| 5430 |
|
| 5431 |
/* walk down the bs forest recursively */
|
| 5432 |
QTAILQ_FOREACH(bs, &bdrv_states, device_list) {
|
| 5433 |
bool perm;
|
| 5434 |
|
| 5435 |
perm = bdrv_recurse_is_first_non_filter(bs, candidate); |
| 5436 |
|
| 5437 |
/* candidate is the first non filter */
|
| 5438 |
if (perm) {
|
| 5439 |
return true; |
| 5440 |
} |
| 5441 |
} |
| 5442 |
|
| 5443 |
return false; |
| 5444 |
} |