qemu/include/block/block_int-io.h

/*
 * QEMU System Emulator block driver
 *
 * Copyright (c) 2003 Fabrice Bellard
 *
 * Permission is hereby granted, free of charge, to any person obtaining a copy
 * of this software and associated documentation files (the "Software"), to deal
 * in the Software without restriction, including without limitation the rights
 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
 * copies of the Software, and to permit persons to whom the Software is
 * furnished to do so, subject to the following conditions:
 *
 * The above copyright notice and this permission notice shall be included in
 * all copies or substantial portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
 * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
 * THE SOFTWARE.
 */
#ifndef BLOCK_INT_IO_H
#define BLOCK_INT_IO_H

#include "block_int-common.h"

/*
 * I/O API functions. These functions are thread-safe.
 *
 * See include/block/block-io.h for more information about
 * the I/O API.
 */

int coroutine_fn bdrv_co_preadv_snapshot(BdrvChild *child,
    int64_t offset, int64_t bytes, QEMUIOVector *qiov, size_t qiov_offset);
int coroutine_fn bdrv_co_snapshot_block_status(BlockDriverState *bs,
    bool want_zero, int64_t offset, int64_t bytes, int64_t *pnum,
    int64_t *map, BlockDriverState **file);
int coroutine_fn bdrv_co_pdiscard_snapshot(BlockDriverState *bs,
    int64_t offset, int64_t bytes);


int coroutine_fn bdrv_co_preadv(BdrvChild *child,
    int64_t offset, int64_t bytes, QEMUIOVector *qiov,
    BdrvRequestFlags flags);
int coroutine_fn bdrv_co_preadv_part(BdrvChild *child,
    int64_t offset, int64_t bytes,
    QEMUIOVector *qiov, size_t qiov_offset, BdrvRequestFlags flags);
int coroutine_fn bdrv_co_pwritev(BdrvChild *child,
    int64_t offset, int64_t bytes, QEMUIOVector *qiov,
    BdrvRequestFlags flags);
int coroutine_fn bdrv_co_pwritev_part(BdrvChild *child,
    int64_t offset, int64_t bytes,
    QEMUIOVector *qiov, size_t qiov_offset, BdrvRequestFlags flags);

static inline int coroutine_fn bdrv_co_pread(BdrvChild *child,
    int64_t offset, unsigned int bytes, void *buf, BdrvRequestFlags flags)
{
    QEMUIOVector qiov = QEMU_IOVEC_INIT_BUF(qiov, buf, bytes);
    IO_CODE();

    return bdrv_co_preadv(child, offset, bytes, &qiov, flags);
}

static inline int coroutine_fn bdrv_co_pwrite(BdrvChild *child,
    int64_t offset, unsigned int bytes, void *buf, BdrvRequestFlags flags)
{
    QEMUIOVector qiov = QEMU_IOVEC_INIT_BUF(qiov, buf, bytes);
    IO_CODE();

    return bdrv_co_pwritev(child, offset, bytes, &qiov, flags);
}

bool coroutine_fn bdrv_make_request_serialising(BdrvTrackedRequest *req,
                                                uint64_t align);
BdrvTrackedRequest *coroutine_fn bdrv_co_get_self_request(BlockDriverState *bs);

BlockDriver *bdrv_probe_all(const uint8_t *buf, int buf_size,
                            const char *filename);

/**
 * bdrv_wakeup:
 * @bs: The BlockDriverState for which an I/O operation has been completed.
 *
 * Wake up the main thread if it is waiting on BDRV_POLL_WHILE.  During
 * synchronous I/O on a BlockDriverState that is attached to another
 * I/O thread, the main thread lets the I/O thread's event loop run,
 * waiting for the I/O operation to complete.  A bdrv_wakeup will wake
 * up the main thread if necessary.
 *
 * Manual calls to bdrv_wakeup are rarely necessary, because
 * bdrv_dec_in_flight already calls it.
 */
void bdrv_wakeup(BlockDriverState *bs);

const char *bdrv_get_parent_name(const BlockDriverState *bs);
bool blk_dev_has_tray(BlockBackend *blk);
bool blk_dev_is_tray_open(BlockBackend *blk);

void bdrv_set_dirty(BlockDriverState *bs, int64_t offset, int64_t bytes);

void bdrv_clear_dirty_bitmap(BdrvDirtyBitmap *bitmap, HBitmap **out);
bool bdrv_dirty_bitmap_merge_internal(BdrvDirtyBitmap *dest,
                                      const BdrvDirtyBitmap *src,
                                      HBitmap **backup, bool lock);

void bdrv_inc_in_flight(BlockDriverState *bs);
void bdrv_dec_in_flight(BlockDriverState *bs);

int coroutine_fn bdrv_co_copy_range_from(BdrvChild *src, int64_t src_offset,
                                         BdrvChild *dst, int64_t dst_offset,
                                         int64_t bytes,
                                         BdrvRequestFlags read_flags,
                                         BdrvRequestFlags write_flags);
int coroutine_fn bdrv_co_copy_range_to(BdrvChild *src, int64_t src_offset,
                                       BdrvChild *dst, int64_t dst_offset,
                                       int64_t bytes,
                                       BdrvRequestFlags read_flags,
                                       BdrvRequestFlags write_flags);

int refresh_total_sectors(BlockDriverState *bs, int64_t hint);

BdrvChild *bdrv_cow_child(BlockDriverState *bs);
BdrvChild *bdrv_filter_child(BlockDriverState *bs);
BdrvChild *bdrv_filter_or_cow_child(BlockDriverState *bs);
BdrvChild *bdrv_primary_child(BlockDriverState *bs);
BlockDriverState *bdrv_skip_filters(BlockDriverState *bs);
BlockDriverState *bdrv_backing_chain_next(BlockDriverState *bs);

static inline BlockDriverState *bdrv_cow_bs(BlockDriverState *bs)
{
    IO_CODE();
    return child_bs(bdrv_cow_child(bs));
}

static inline BlockDriverState *bdrv_filter_bs(BlockDriverState *bs)
{
    IO_CODE();
    return child_bs(bdrv_filter_child(bs));
}

static inline BlockDriverState *bdrv_filter_or_cow_bs(BlockDriverState *bs)
{
    IO_CODE();
    return child_bs(bdrv_filter_or_cow_child(bs));
}

static inline BlockDriverState *bdrv_primary_bs(BlockDriverState *bs)
{
    IO_CODE();
    return child_bs(bdrv_primary_child(bs));
}

/**
 * Check whether the given offset is in the cached block-status data
 * region.
 *
 * If it is, and @pnum is not NULL, *pnum is set to
 * `bsc.data_end - offset`, i.e. how many bytes, starting from
 * @offset, are data (according to the cache).
 * Otherwise, *pnum is not touched.
 */
bool bdrv_bsc_is_data(BlockDriverState *bs, int64_t offset, int64_t *pnum);

/**
 * If [offset, offset + bytes) overlaps with the currently cached
 * block-status region, invalidate the cache.
 *
 * (To be used by I/O paths that cause data regions to be zero or
 * holes.)
 */
void bdrv_bsc_invalidate_range(BlockDriverState *bs,
                               int64_t offset, int64_t bytes);

/**
 * Mark the range [offset, offset + bytes) as a data region.
 */
void bdrv_bsc_fill(BlockDriverState *bs, int64_t offset, int64_t bytes);


/*
 * "I/O or GS" API functions. These functions can run without
 * the BQL, but only in one specific iothread/main loop.
 *
 * See include/block/block-io.h for more information about
 * the "I/O or GS" API.
 */

void bdrv_apply_subtree_drain(BdrvChild *child, BlockDriverState *new_parent);
void bdrv_unapply_subtree_drain(BdrvChild *child, BlockDriverState *old_parent);

#endif /* BLOCK_INT_IO_H */