5def6b80e1
Sector-based limits are awkward to think about; in our on-going quest to move to byte-based interfaces, convert max_transfer_length and opt_transfer_length. Rename them (dropping the _length suffix) so that the compiler will help us catch the change in semantics across any rebased code, and improve the documentation. Use unsigned values, so that we don't have to worry about negative values and so that bit-twiddling is easier; however, we are still constrained by 2^31 of signed int in most APIs. When a value comes from an external source (iscsi and raw-posix), sanitize the results to ensure that opt_transfer is a power of 2. Signed-off-by: Eric Blake <eblake@redhat.com> Reviewed-by: Fam Zheng <famz@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
765 lines
30 KiB
C
765 lines
30 KiB
C
/*
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* QEMU System Emulator block driver
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*
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* Copyright (c) 2003 Fabrice Bellard
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*
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* Permission is hereby granted, free of charge, to any person obtaining a copy
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* of this software and associated documentation files (the "Software"), to deal
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* in the Software without restriction, including without limitation the rights
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* to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
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* copies of the Software, and to permit persons to whom the Software is
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* furnished to do so, subject to the following conditions:
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*
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* The above copyright notice and this permission notice shall be included in
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* all copies or substantial portions of the Software.
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*
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* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
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* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
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* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
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* THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
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* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
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* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
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* THE SOFTWARE.
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*/
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#ifndef BLOCK_INT_H
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#define BLOCK_INT_H
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#include "block/accounting.h"
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#include "block/block.h"
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#include "qemu/option.h"
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#include "qemu/queue.h"
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#include "qemu/coroutine.h"
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#include "qemu/timer.h"
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#include "qapi-types.h"
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#include "qemu/hbitmap.h"
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#include "block/snapshot.h"
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#include "qemu/main-loop.h"
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#include "qemu/throttle.h"
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#define BLOCK_FLAG_ENCRYPT 1
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#define BLOCK_FLAG_LAZY_REFCOUNTS 8
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#define BLOCK_OPT_SIZE "size"
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#define BLOCK_OPT_ENCRYPT "encryption"
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#define BLOCK_OPT_COMPAT6 "compat6"
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#define BLOCK_OPT_HWVERSION "hwversion"
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#define BLOCK_OPT_BACKING_FILE "backing_file"
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#define BLOCK_OPT_BACKING_FMT "backing_fmt"
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#define BLOCK_OPT_CLUSTER_SIZE "cluster_size"
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#define BLOCK_OPT_TABLE_SIZE "table_size"
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#define BLOCK_OPT_PREALLOC "preallocation"
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#define BLOCK_OPT_SUBFMT "subformat"
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#define BLOCK_OPT_COMPAT_LEVEL "compat"
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#define BLOCK_OPT_LAZY_REFCOUNTS "lazy_refcounts"
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#define BLOCK_OPT_ADAPTER_TYPE "adapter_type"
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#define BLOCK_OPT_REDUNDANCY "redundancy"
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#define BLOCK_OPT_NOCOW "nocow"
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#define BLOCK_OPT_OBJECT_SIZE "object_size"
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#define BLOCK_OPT_REFCOUNT_BITS "refcount_bits"
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#define BLOCK_PROBE_BUF_SIZE 512
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enum BdrvTrackedRequestType {
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BDRV_TRACKED_READ,
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BDRV_TRACKED_WRITE,
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BDRV_TRACKED_FLUSH,
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BDRV_TRACKED_IOCTL,
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BDRV_TRACKED_DISCARD,
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};
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typedef struct BdrvTrackedRequest {
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BlockDriverState *bs;
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int64_t offset;
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unsigned int bytes;
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enum BdrvTrackedRequestType type;
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bool serialising;
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int64_t overlap_offset;
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unsigned int overlap_bytes;
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QLIST_ENTRY(BdrvTrackedRequest) list;
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Coroutine *co; /* owner, used for deadlock detection */
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CoQueue wait_queue; /* coroutines blocked on this request */
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struct BdrvTrackedRequest *waiting_for;
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} BdrvTrackedRequest;
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struct BlockDriver {
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const char *format_name;
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int instance_size;
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/* set to true if the BlockDriver is a block filter */
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bool is_filter;
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/* for snapshots block filter like Quorum can implement the
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* following recursive callback.
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* It's purpose is to recurse on the filter children while calling
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* bdrv_recurse_is_first_non_filter on them.
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* For a sample implementation look in the future Quorum block filter.
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*/
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bool (*bdrv_recurse_is_first_non_filter)(BlockDriverState *bs,
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BlockDriverState *candidate);
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int (*bdrv_probe)(const uint8_t *buf, int buf_size, const char *filename);
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int (*bdrv_probe_device)(const char *filename);
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/* Any driver implementing this callback is expected to be able to handle
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* NULL file names in its .bdrv_open() implementation */
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void (*bdrv_parse_filename)(const char *filename, QDict *options, Error **errp);
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/* Drivers not implementing bdrv_parse_filename nor bdrv_open should have
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* this field set to true, except ones that are defined only by their
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* child's bs.
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* An example of the last type will be the quorum block driver.
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*/
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bool bdrv_needs_filename;
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/* Set if a driver can support backing files */
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bool supports_backing;
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/* For handling image reopen for split or non-split files */
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int (*bdrv_reopen_prepare)(BDRVReopenState *reopen_state,
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BlockReopenQueue *queue, Error **errp);
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void (*bdrv_reopen_commit)(BDRVReopenState *reopen_state);
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void (*bdrv_reopen_abort)(BDRVReopenState *reopen_state);
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void (*bdrv_join_options)(QDict *options, QDict *old_options);
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int (*bdrv_open)(BlockDriverState *bs, QDict *options, int flags,
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Error **errp);
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int (*bdrv_file_open)(BlockDriverState *bs, QDict *options, int flags,
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Error **errp);
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void (*bdrv_close)(BlockDriverState *bs);
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int (*bdrv_create)(const char *filename, QemuOpts *opts, Error **errp);
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int (*bdrv_set_key)(BlockDriverState *bs, const char *key);
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int (*bdrv_make_empty)(BlockDriverState *bs);
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void (*bdrv_refresh_filename)(BlockDriverState *bs, QDict *options);
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/* aio */
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BlockAIOCB *(*bdrv_aio_readv)(BlockDriverState *bs,
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int64_t sector_num, QEMUIOVector *qiov, int nb_sectors,
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BlockCompletionFunc *cb, void *opaque);
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BlockAIOCB *(*bdrv_aio_writev)(BlockDriverState *bs,
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int64_t sector_num, QEMUIOVector *qiov, int nb_sectors,
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BlockCompletionFunc *cb, void *opaque);
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BlockAIOCB *(*bdrv_aio_flush)(BlockDriverState *bs,
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BlockCompletionFunc *cb, void *opaque);
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BlockAIOCB *(*bdrv_aio_discard)(BlockDriverState *bs,
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int64_t sector_num, int nb_sectors,
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BlockCompletionFunc *cb, void *opaque);
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int coroutine_fn (*bdrv_co_readv)(BlockDriverState *bs,
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int64_t sector_num, int nb_sectors, QEMUIOVector *qiov);
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int coroutine_fn (*bdrv_co_preadv)(BlockDriverState *bs,
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uint64_t offset, uint64_t bytes, QEMUIOVector *qiov, int flags);
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int coroutine_fn (*bdrv_co_writev)(BlockDriverState *bs,
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int64_t sector_num, int nb_sectors, QEMUIOVector *qiov);
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int coroutine_fn (*bdrv_co_writev_flags)(BlockDriverState *bs,
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int64_t sector_num, int nb_sectors, QEMUIOVector *qiov, int flags);
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int coroutine_fn (*bdrv_co_pwritev)(BlockDriverState *bs,
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uint64_t offset, uint64_t bytes, QEMUIOVector *qiov, int flags);
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/*
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* Efficiently zero a region of the disk image. Typically an image format
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* would use a compact metadata representation to implement this. This
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* function pointer may be NULL or return -ENOSUP and .bdrv_co_writev()
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* will be called instead.
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*/
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int coroutine_fn (*bdrv_co_pwrite_zeroes)(BlockDriverState *bs,
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int64_t offset, int count, BdrvRequestFlags flags);
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int coroutine_fn (*bdrv_co_discard)(BlockDriverState *bs,
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int64_t sector_num, int nb_sectors);
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int64_t coroutine_fn (*bdrv_co_get_block_status)(BlockDriverState *bs,
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int64_t sector_num, int nb_sectors, int *pnum,
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BlockDriverState **file);
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/*
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* Invalidate any cached meta-data.
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*/
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void (*bdrv_invalidate_cache)(BlockDriverState *bs, Error **errp);
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int (*bdrv_inactivate)(BlockDriverState *bs);
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/*
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* Flushes all data for all layers by calling bdrv_co_flush for underlying
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* layers, if needed. This function is needed for deterministic
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* synchronization of the flush finishing callback.
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*/
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int coroutine_fn (*bdrv_co_flush)(BlockDriverState *bs);
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/*
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* Flushes all data that was already written to the OS all the way down to
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* the disk (for example raw-posix calls fsync()).
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*/
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int coroutine_fn (*bdrv_co_flush_to_disk)(BlockDriverState *bs);
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/*
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* Flushes all internal caches to the OS. The data may still sit in a
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* writeback cache of the host OS, but it will survive a crash of the qemu
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* process.
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*/
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int coroutine_fn (*bdrv_co_flush_to_os)(BlockDriverState *bs);
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const char *protocol_name;
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int (*bdrv_truncate)(BlockDriverState *bs, int64_t offset);
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int64_t (*bdrv_getlength)(BlockDriverState *bs);
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bool has_variable_length;
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int64_t (*bdrv_get_allocated_file_size)(BlockDriverState *bs);
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int (*bdrv_write_compressed)(BlockDriverState *bs, int64_t sector_num,
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const uint8_t *buf, int nb_sectors);
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int (*bdrv_snapshot_create)(BlockDriverState *bs,
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QEMUSnapshotInfo *sn_info);
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int (*bdrv_snapshot_goto)(BlockDriverState *bs,
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const char *snapshot_id);
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int (*bdrv_snapshot_delete)(BlockDriverState *bs,
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const char *snapshot_id,
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const char *name,
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Error **errp);
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int (*bdrv_snapshot_list)(BlockDriverState *bs,
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QEMUSnapshotInfo **psn_info);
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int (*bdrv_snapshot_load_tmp)(BlockDriverState *bs,
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const char *snapshot_id,
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const char *name,
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Error **errp);
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int (*bdrv_get_info)(BlockDriverState *bs, BlockDriverInfo *bdi);
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ImageInfoSpecific *(*bdrv_get_specific_info)(BlockDriverState *bs);
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int coroutine_fn (*bdrv_save_vmstate)(BlockDriverState *bs,
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QEMUIOVector *qiov,
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int64_t pos);
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int coroutine_fn (*bdrv_load_vmstate)(BlockDriverState *bs,
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QEMUIOVector *qiov,
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int64_t pos);
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int (*bdrv_change_backing_file)(BlockDriverState *bs,
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const char *backing_file, const char *backing_fmt);
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/* removable device specific */
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bool (*bdrv_is_inserted)(BlockDriverState *bs);
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int (*bdrv_media_changed)(BlockDriverState *bs);
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void (*bdrv_eject)(BlockDriverState *bs, bool eject_flag);
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void (*bdrv_lock_medium)(BlockDriverState *bs, bool locked);
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/* to control generic scsi devices */
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BlockAIOCB *(*bdrv_aio_ioctl)(BlockDriverState *bs,
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unsigned long int req, void *buf,
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BlockCompletionFunc *cb, void *opaque);
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/* List of options for creating images, terminated by name == NULL */
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QemuOptsList *create_opts;
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/*
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* Returns 0 for completed check, -errno for internal errors.
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* The check results are stored in result.
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*/
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int (*bdrv_check)(BlockDriverState* bs, BdrvCheckResult *result,
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BdrvCheckMode fix);
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int (*bdrv_amend_options)(BlockDriverState *bs, QemuOpts *opts,
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BlockDriverAmendStatusCB *status_cb,
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void *cb_opaque);
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void (*bdrv_debug_event)(BlockDriverState *bs, BlkdebugEvent event);
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/* TODO Better pass a option string/QDict/QemuOpts to add any rule? */
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int (*bdrv_debug_breakpoint)(BlockDriverState *bs, const char *event,
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const char *tag);
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int (*bdrv_debug_remove_breakpoint)(BlockDriverState *bs,
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const char *tag);
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int (*bdrv_debug_resume)(BlockDriverState *bs, const char *tag);
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bool (*bdrv_debug_is_suspended)(BlockDriverState *bs, const char *tag);
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void (*bdrv_refresh_limits)(BlockDriverState *bs, Error **errp);
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/*
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* Returns 1 if newly created images are guaranteed to contain only
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* zeros, 0 otherwise.
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*/
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int (*bdrv_has_zero_init)(BlockDriverState *bs);
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/* Remove fd handlers, timers, and other event loop callbacks so the event
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* loop is no longer in use. Called with no in-flight requests and in
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* depth-first traversal order with parents before child nodes.
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*/
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void (*bdrv_detach_aio_context)(BlockDriverState *bs);
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/* Add fd handlers, timers, and other event loop callbacks so I/O requests
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* can be processed again. Called with no in-flight requests and in
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* depth-first traversal order with child nodes before parent nodes.
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*/
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void (*bdrv_attach_aio_context)(BlockDriverState *bs,
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AioContext *new_context);
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/* io queue for linux-aio */
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void (*bdrv_io_plug)(BlockDriverState *bs);
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void (*bdrv_io_unplug)(BlockDriverState *bs);
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/**
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* Try to get @bs's logical and physical block size.
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* On success, store them in @bsz and return zero.
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* On failure, return negative errno.
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*/
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int (*bdrv_probe_blocksizes)(BlockDriverState *bs, BlockSizes *bsz);
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/**
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* Try to get @bs's geometry (cyls, heads, sectors)
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* On success, store them in @geo and return 0.
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* On failure return -errno.
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* Only drivers that want to override guest geometry implement this
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* callback; see hd_geometry_guess().
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*/
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int (*bdrv_probe_geometry)(BlockDriverState *bs, HDGeometry *geo);
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/**
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* Drain and stop any internal sources of requests in the driver, and
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* remain so until next I/O callback (e.g. bdrv_co_writev) is called.
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*/
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void (*bdrv_drain)(BlockDriverState *bs);
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void (*bdrv_add_child)(BlockDriverState *parent, BlockDriverState *child,
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Error **errp);
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void (*bdrv_del_child)(BlockDriverState *parent, BdrvChild *child,
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Error **errp);
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QLIST_ENTRY(BlockDriver) list;
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};
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typedef struct BlockLimits {
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/* maximum number of sectors that can be discarded at once */
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int max_discard;
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/* optimal alignment for discard requests in sectors */
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int64_t discard_alignment;
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/* maximum number of bytes that can zeroized at once (since it is
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* signed, it must be < 2G, if set) */
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int32_t max_pwrite_zeroes;
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/* optimal alignment for write zeroes requests in bytes, must be
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* power of 2, and less than max_pwrite_zeroes if that is set */
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uint32_t pwrite_zeroes_alignment;
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/* optimal transfer length in bytes (must be power of 2, and
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* multiple of bs->request_alignment), or 0 if no preferred size */
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uint32_t opt_transfer;
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/* maximal transfer length in bytes (need not be power of 2, but
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* should be multiple of opt_transfer), or 0 for no 32-bit limit.
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* For now, anything larger than INT_MAX is clamped down. */
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uint32_t max_transfer;
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/* memory alignment so that no bounce buffer is needed */
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size_t min_mem_alignment;
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/* memory alignment for bounce buffer */
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size_t opt_mem_alignment;
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/* maximum number of iovec elements */
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int max_iov;
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} BlockLimits;
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typedef struct BdrvOpBlocker BdrvOpBlocker;
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typedef struct BdrvAioNotifier {
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void (*attached_aio_context)(AioContext *new_context, void *opaque);
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void (*detach_aio_context)(void *opaque);
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void *opaque;
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bool deleted;
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QLIST_ENTRY(BdrvAioNotifier) list;
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} BdrvAioNotifier;
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struct BdrvChildRole {
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void (*inherit_options)(int *child_flags, QDict *child_options,
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int parent_flags, QDict *parent_options);
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void (*change_media)(BdrvChild *child, bool load);
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void (*resize)(BdrvChild *child);
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/* Returns a name that is supposedly more useful for human users than the
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* node name for identifying the node in question (in particular, a BB
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* name), or NULL if the parent can't provide a better name. */
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const char* (*get_name)(BdrvChild *child);
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/*
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* If this pair of functions is implemented, the parent doesn't issue new
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* requests after returning from .drained_begin() until .drained_end() is
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* called.
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*
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* Note that this can be nested. If drained_begin() was called twice, new
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* I/O is allowed only after drained_end() was called twice, too.
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*/
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void (*drained_begin)(BdrvChild *child);
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void (*drained_end)(BdrvChild *child);
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};
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extern const BdrvChildRole child_file;
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extern const BdrvChildRole child_format;
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struct BdrvChild {
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BlockDriverState *bs;
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char *name;
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const BdrvChildRole *role;
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void *opaque;
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QLIST_ENTRY(BdrvChild) next;
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QLIST_ENTRY(BdrvChild) next_parent;
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};
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/*
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* Note: the function bdrv_append() copies and swaps contents of
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* BlockDriverStates, so if you add new fields to this struct, please
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* inspect bdrv_append() to determine if the new fields need to be
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* copied as well.
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*/
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struct BlockDriverState {
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int64_t total_sectors; /* if we are reading a disk image, give its
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size in sectors */
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int read_only; /* if true, the media is read only */
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int open_flags; /* flags used to open the file, re-used for re-open */
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int encrypted; /* if true, the media is encrypted */
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int valid_key; /* if true, a valid encryption key has been set */
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int sg; /* if true, the device is a /dev/sg* */
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int copy_on_read; /* if true, copy read backing sectors into image
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note this is a reference count */
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bool probed;
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BlockDriver *drv; /* NULL means no media */
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void *opaque;
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AioContext *aio_context; /* event loop used for fd handlers, timers, etc */
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/* long-running tasks intended to always use the same AioContext as this
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* BDS may register themselves in this list to be notified of changes
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* regarding this BDS's context */
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QLIST_HEAD(, BdrvAioNotifier) aio_notifiers;
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bool walking_aio_notifiers; /* to make removal during iteration safe */
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char filename[PATH_MAX];
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char backing_file[PATH_MAX]; /* if non zero, the image is a diff of
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this file image */
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char backing_format[16]; /* if non-zero and backing_file exists */
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QDict *full_open_options;
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char exact_filename[PATH_MAX];
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BdrvChild *backing;
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BdrvChild *file;
|
|
|
|
/* Callback before write request is processed */
|
|
NotifierWithReturnList before_write_notifiers;
|
|
|
|
/* number of in-flight serialising requests */
|
|
unsigned int serialising_in_flight;
|
|
|
|
/* Offset after the highest byte written to */
|
|
uint64_t wr_highest_offset;
|
|
|
|
/* I/O Limits */
|
|
BlockLimits bl;
|
|
|
|
/* Alignment requirement for offset/length of I/O requests */
|
|
unsigned int request_alignment;
|
|
/* Flags honored during pwrite (so far: BDRV_REQ_FUA) */
|
|
unsigned int supported_write_flags;
|
|
/* Flags honored during pwrite_zeroes (so far: BDRV_REQ_FUA,
|
|
* BDRV_REQ_MAY_UNMAP) */
|
|
unsigned int supported_zero_flags;
|
|
|
|
/* the following member gives a name to every node on the bs graph. */
|
|
char node_name[32];
|
|
/* element of the list of named nodes building the graph */
|
|
QTAILQ_ENTRY(BlockDriverState) node_list;
|
|
/* element of the list of all BlockDriverStates (all_bdrv_states) */
|
|
QTAILQ_ENTRY(BlockDriverState) bs_list;
|
|
/* element of the list of monitor-owned BDS */
|
|
QTAILQ_ENTRY(BlockDriverState) monitor_list;
|
|
QLIST_HEAD(, BdrvDirtyBitmap) dirty_bitmaps;
|
|
int refcnt;
|
|
|
|
QLIST_HEAD(, BdrvTrackedRequest) tracked_requests;
|
|
|
|
/* operation blockers */
|
|
QLIST_HEAD(, BdrvOpBlocker) op_blockers[BLOCK_OP_TYPE_MAX];
|
|
|
|
/* long-running background operation */
|
|
BlockJob *job;
|
|
|
|
/* The node that this node inherited default options from (and a reopen on
|
|
* which can affect this node by changing these defaults). This is always a
|
|
* parent node of this node. */
|
|
BlockDriverState *inherits_from;
|
|
QLIST_HEAD(, BdrvChild) children;
|
|
QLIST_HEAD(, BdrvChild) parents;
|
|
|
|
QDict *options;
|
|
QDict *explicit_options;
|
|
BlockdevDetectZeroesOptions detect_zeroes;
|
|
|
|
/* The error object in use for blocking operations on backing_hd */
|
|
Error *backing_blocker;
|
|
|
|
/* threshold limit for writes, in bytes. "High water mark". */
|
|
uint64_t write_threshold_offset;
|
|
NotifierWithReturn write_threshold_notifier;
|
|
|
|
/* counters for nested bdrv_io_plug and bdrv_io_unplugged_begin */
|
|
unsigned io_plugged;
|
|
unsigned io_plug_disabled;
|
|
|
|
int quiesce_counter;
|
|
};
|
|
|
|
struct BlockBackendRootState {
|
|
int open_flags;
|
|
bool read_only;
|
|
BlockdevDetectZeroesOptions detect_zeroes;
|
|
};
|
|
|
|
typedef enum BlockMirrorBackingMode {
|
|
/* Reuse the existing backing chain from the source for the target.
|
|
* - sync=full: Set backing BDS to NULL.
|
|
* - sync=top: Use source's backing BDS.
|
|
* - sync=none: Use source as the backing BDS. */
|
|
MIRROR_SOURCE_BACKING_CHAIN,
|
|
|
|
/* Open the target's backing chain completely anew */
|
|
MIRROR_OPEN_BACKING_CHAIN,
|
|
|
|
/* Do not change the target's backing BDS after job completion */
|
|
MIRROR_LEAVE_BACKING_CHAIN,
|
|
} BlockMirrorBackingMode;
|
|
|
|
static inline BlockDriverState *backing_bs(BlockDriverState *bs)
|
|
{
|
|
return bs->backing ? bs->backing->bs : NULL;
|
|
}
|
|
|
|
|
|
/* Essential block drivers which must always be statically linked into qemu, and
|
|
* which therefore can be accessed without using bdrv_find_format() */
|
|
extern BlockDriver bdrv_file;
|
|
extern BlockDriver bdrv_raw;
|
|
extern BlockDriver bdrv_qcow2;
|
|
|
|
/**
|
|
* bdrv_setup_io_funcs:
|
|
*
|
|
* Prepare a #BlockDriver for I/O request processing by populating
|
|
* unimplemented coroutine and AIO interfaces with generic wrapper functions
|
|
* that fall back to implemented interfaces.
|
|
*/
|
|
void bdrv_setup_io_funcs(BlockDriver *bdrv);
|
|
|
|
int coroutine_fn bdrv_co_preadv(BlockDriverState *bs,
|
|
int64_t offset, unsigned int bytes, QEMUIOVector *qiov,
|
|
BdrvRequestFlags flags);
|
|
int coroutine_fn bdrv_co_pwritev(BlockDriverState *bs,
|
|
int64_t offset, unsigned int bytes, QEMUIOVector *qiov,
|
|
BdrvRequestFlags flags);
|
|
|
|
int get_tmp_filename(char *filename, int size);
|
|
BlockDriver *bdrv_probe_all(const uint8_t *buf, int buf_size,
|
|
const char *filename);
|
|
|
|
|
|
/**
|
|
* bdrv_add_before_write_notifier:
|
|
*
|
|
* Register a callback that is invoked before write requests are processed but
|
|
* after any throttling or waiting for overlapping requests.
|
|
*/
|
|
void bdrv_add_before_write_notifier(BlockDriverState *bs,
|
|
NotifierWithReturn *notifier);
|
|
|
|
/**
|
|
* bdrv_detach_aio_context:
|
|
*
|
|
* May be called from .bdrv_detach_aio_context() to detach children from the
|
|
* current #AioContext. This is only needed by block drivers that manage their
|
|
* own children. Both ->file and ->backing are automatically handled and
|
|
* block drivers should not call this function on them explicitly.
|
|
*/
|
|
void bdrv_detach_aio_context(BlockDriverState *bs);
|
|
|
|
/**
|
|
* bdrv_attach_aio_context:
|
|
*
|
|
* May be called from .bdrv_attach_aio_context() to attach children to the new
|
|
* #AioContext. This is only needed by block drivers that manage their own
|
|
* children. Both ->file and ->backing are automatically handled and block
|
|
* drivers should not call this function on them explicitly.
|
|
*/
|
|
void bdrv_attach_aio_context(BlockDriverState *bs,
|
|
AioContext *new_context);
|
|
|
|
/**
|
|
* bdrv_add_aio_context_notifier:
|
|
*
|
|
* If a long-running job intends to be always run in the same AioContext as a
|
|
* certain BDS, it may use this function to be notified of changes regarding the
|
|
* association of the BDS to an AioContext.
|
|
*
|
|
* attached_aio_context() is called after the target BDS has been attached to a
|
|
* new AioContext; detach_aio_context() is called before the target BDS is being
|
|
* detached from its old AioContext.
|
|
*/
|
|
void bdrv_add_aio_context_notifier(BlockDriverState *bs,
|
|
void (*attached_aio_context)(AioContext *new_context, void *opaque),
|
|
void (*detach_aio_context)(void *opaque), void *opaque);
|
|
|
|
/**
|
|
* bdrv_remove_aio_context_notifier:
|
|
*
|
|
* Unsubscribe of change notifications regarding the BDS's AioContext. The
|
|
* parameters given here have to be the same as those given to
|
|
* bdrv_add_aio_context_notifier().
|
|
*/
|
|
void bdrv_remove_aio_context_notifier(BlockDriverState *bs,
|
|
void (*aio_context_attached)(AioContext *,
|
|
void *),
|
|
void (*aio_context_detached)(void *),
|
|
void *opaque);
|
|
|
|
#ifdef _WIN32
|
|
int is_windows_drive(const char *filename);
|
|
#endif
|
|
|
|
/**
|
|
* stream_start:
|
|
* @bs: Block device to operate on.
|
|
* @base: Block device that will become the new base, or %NULL to
|
|
* flatten the whole backing file chain onto @bs.
|
|
* @base_id: The file name that will be written to @bs as the new
|
|
* backing file if the job completes. Ignored if @base is %NULL.
|
|
* @speed: The maximum speed, in bytes per second, or 0 for unlimited.
|
|
* @on_error: The action to take upon error.
|
|
* @cb: Completion function for the job.
|
|
* @opaque: Opaque pointer value passed to @cb.
|
|
* @errp: Error object.
|
|
*
|
|
* Start a streaming operation on @bs. Clusters that are unallocated
|
|
* in @bs, but allocated in any image between @base and @bs (both
|
|
* exclusive) will be written to @bs. At the end of a successful
|
|
* streaming job, the backing file of @bs will be changed to
|
|
* @base_id in the written image and to @base in the live BlockDriverState.
|
|
*/
|
|
void stream_start(BlockDriverState *bs, BlockDriverState *base,
|
|
const char *base_id, int64_t speed, BlockdevOnError on_error,
|
|
BlockCompletionFunc *cb,
|
|
void *opaque, Error **errp);
|
|
|
|
/**
|
|
* commit_start:
|
|
* @bs: Active block device.
|
|
* @top: Top block device to be committed.
|
|
* @base: Block device that will be written into, and become the new top.
|
|
* @speed: The maximum speed, in bytes per second, or 0 for unlimited.
|
|
* @on_error: The action to take upon error.
|
|
* @cb: Completion function for the job.
|
|
* @opaque: Opaque pointer value passed to @cb.
|
|
* @backing_file_str: String to use as the backing file in @top's overlay
|
|
* @errp: Error object.
|
|
*
|
|
*/
|
|
void commit_start(BlockDriverState *bs, BlockDriverState *base,
|
|
BlockDriverState *top, int64_t speed,
|
|
BlockdevOnError on_error, BlockCompletionFunc *cb,
|
|
void *opaque, const char *backing_file_str, Error **errp);
|
|
/**
|
|
* commit_active_start:
|
|
* @bs: Active block device to be committed.
|
|
* @base: Block device that will be written into, and become the new top.
|
|
* @speed: The maximum speed, in bytes per second, or 0 for unlimited.
|
|
* @on_error: The action to take upon error.
|
|
* @cb: Completion function for the job.
|
|
* @opaque: Opaque pointer value passed to @cb.
|
|
* @errp: Error object.
|
|
*
|
|
*/
|
|
void commit_active_start(BlockDriverState *bs, BlockDriverState *base,
|
|
int64_t speed,
|
|
BlockdevOnError on_error,
|
|
BlockCompletionFunc *cb,
|
|
void *opaque, Error **errp);
|
|
/*
|
|
* mirror_start:
|
|
* @bs: Block device to operate on.
|
|
* @target: Block device to write to.
|
|
* @replaces: Block graph node name to replace once the mirror is done. Can
|
|
* only be used when full mirroring is selected.
|
|
* @speed: The maximum speed, in bytes per second, or 0 for unlimited.
|
|
* @granularity: The chosen granularity for the dirty bitmap.
|
|
* @buf_size: The amount of data that can be in flight at one time.
|
|
* @mode: Whether to collapse all images in the chain to the target.
|
|
* @backing_mode: How to establish the target's backing chain after completion.
|
|
* @on_source_error: The action to take upon error reading from the source.
|
|
* @on_target_error: The action to take upon error writing to the target.
|
|
* @unmap: Whether to unmap target where source sectors only contain zeroes.
|
|
* @cb: Completion function for the job.
|
|
* @opaque: Opaque pointer value passed to @cb.
|
|
* @errp: Error object.
|
|
*
|
|
* Start a mirroring operation on @bs. Clusters that are allocated
|
|
* in @bs will be written to @bs until the job is cancelled or
|
|
* manually completed. At the end of a successful mirroring job,
|
|
* @bs will be switched to read from @target.
|
|
*/
|
|
void mirror_start(BlockDriverState *bs, BlockDriverState *target,
|
|
const char *replaces,
|
|
int64_t speed, uint32_t granularity, int64_t buf_size,
|
|
MirrorSyncMode mode, BlockMirrorBackingMode backing_mode,
|
|
BlockdevOnError on_source_error,
|
|
BlockdevOnError on_target_error,
|
|
bool unmap,
|
|
BlockCompletionFunc *cb,
|
|
void *opaque, Error **errp);
|
|
|
|
/*
|
|
* backup_start:
|
|
* @bs: Block device to operate on.
|
|
* @target: Block device to write to.
|
|
* @speed: The maximum speed, in bytes per second, or 0 for unlimited.
|
|
* @sync_mode: What parts of the disk image should be copied to the destination.
|
|
* @sync_bitmap: The dirty bitmap if sync_mode is MIRROR_SYNC_MODE_INCREMENTAL.
|
|
* @on_source_error: The action to take upon error reading from the source.
|
|
* @on_target_error: The action to take upon error writing to the target.
|
|
* @cb: Completion function for the job.
|
|
* @opaque: Opaque pointer value passed to @cb.
|
|
* @txn: Transaction that this job is part of (may be NULL).
|
|
*
|
|
* Start a backup operation on @bs. Clusters in @bs are written to @target
|
|
* until the job is cancelled or manually completed.
|
|
*/
|
|
void backup_start(BlockDriverState *bs, BlockDriverState *target,
|
|
int64_t speed, MirrorSyncMode sync_mode,
|
|
BdrvDirtyBitmap *sync_bitmap,
|
|
BlockdevOnError on_source_error,
|
|
BlockdevOnError on_target_error,
|
|
BlockCompletionFunc *cb, void *opaque,
|
|
BlockJobTxn *txn, Error **errp);
|
|
|
|
void hmp_drive_add_node(Monitor *mon, const char *optstr);
|
|
|
|
BdrvChild *bdrv_root_attach_child(BlockDriverState *child_bs,
|
|
const char *child_name,
|
|
const BdrvChildRole *child_role,
|
|
void *opaque);
|
|
void bdrv_root_unref_child(BdrvChild *child);
|
|
|
|
const char *bdrv_get_parent_name(const BlockDriverState *bs);
|
|
void blk_dev_change_media_cb(BlockBackend *blk, bool load);
|
|
bool blk_dev_has_removable_media(BlockBackend *blk);
|
|
bool blk_dev_has_tray(BlockBackend *blk);
|
|
void blk_dev_eject_request(BlockBackend *blk, bool force);
|
|
bool blk_dev_is_tray_open(BlockBackend *blk);
|
|
bool blk_dev_is_medium_locked(BlockBackend *blk);
|
|
|
|
void bdrv_set_dirty(BlockDriverState *bs, int64_t cur_sector, int nr_sectors);
|
|
bool bdrv_requests_pending(BlockDriverState *bs);
|
|
|
|
void bdrv_clear_dirty_bitmap(BdrvDirtyBitmap *bitmap, HBitmap **out);
|
|
void bdrv_undo_clear_dirty_bitmap(BdrvDirtyBitmap *bitmap, HBitmap *in);
|
|
|
|
void blockdev_close_all_bdrv_states(void);
|
|
|
|
#endif /* BLOCK_INT_H */
|