We are going to use bdrv_co_pwritev_part and bdrv_co_preadv_part in bdrv_rw_co_entry, so move it down.
Note: Comment formatting was changed to conform to coding style and function order was changed. Otherwise the code is unmodified. Signed-off-by: Vladimir Sementsov-Ogievskiy <vsement...@virtuozzo.com> Reviewed-by: Stefan Hajnoczi <stefa...@redhat.com> --- block/io.c | 361 +++++++++++++++++++++++++++-------------------------- 1 file changed, 181 insertions(+), 180 deletions(-) diff --git a/block/io.c b/block/io.c index 1134f8144a..061f3f2590 100644 --- a/block/io.c +++ b/block/io.c @@ -891,186 +891,6 @@ static int bdrv_check_byte_request(BlockDriverState *bs, int64_t offset, return 0; } -typedef struct RwCo { - BdrvChild *child; - int64_t offset; - QEMUIOVector *qiov; - bool is_write; - int ret; - BdrvRequestFlags flags; -} RwCo; - -static void coroutine_fn bdrv_rw_co_entry(void *opaque) -{ - RwCo *rwco = opaque; - - if (!rwco->is_write) { - rwco->ret = bdrv_co_preadv(rwco->child, rwco->offset, - rwco->qiov->size, rwco->qiov, - rwco->flags); - } else { - rwco->ret = bdrv_co_pwritev(rwco->child, rwco->offset, - rwco->qiov->size, rwco->qiov, - rwco->flags); - } - aio_wait_kick(); -} - -/* - * Process a vectored synchronous request using coroutines - */ -static int bdrv_prwv_co(BdrvChild *child, int64_t offset, - QEMUIOVector *qiov, bool is_write, - BdrvRequestFlags flags) -{ - Coroutine *co; - RwCo rwco = { - .child = child, - .offset = offset, - .qiov = qiov, - .is_write = is_write, - .ret = NOT_DONE, - .flags = flags, - }; - - if (qemu_in_coroutine()) { - /* Fast-path if already in coroutine context */ - bdrv_rw_co_entry(&rwco); - } else { - co = qemu_coroutine_create(bdrv_rw_co_entry, &rwco); - bdrv_coroutine_enter(child->bs, co); - BDRV_POLL_WHILE(child->bs, rwco.ret == NOT_DONE); - } - return rwco.ret; -} - -int bdrv_pwrite_zeroes(BdrvChild *child, int64_t offset, - int bytes, BdrvRequestFlags flags) -{ - QEMUIOVector qiov = QEMU_IOVEC_INIT_BUF(qiov, NULL, bytes); - - return bdrv_prwv_co(child, offset, &qiov, true, - BDRV_REQ_ZERO_WRITE | flags); -} - -/* - * Completely zero out a block device with the help of bdrv_pwrite_zeroes. - * The operation is sped up by checking the block status and only writing - * zeroes to the device if they currently do not return zeroes. Optional - * flags are passed through to bdrv_pwrite_zeroes (e.g. BDRV_REQ_MAY_UNMAP, - * BDRV_REQ_FUA). - * - * Returns < 0 on error, 0 on success. For error codes see bdrv_write(). - */ -int bdrv_make_zero(BdrvChild *child, BdrvRequestFlags flags) -{ - int ret; - int64_t target_size, bytes, offset = 0; - BlockDriverState *bs = child->bs; - - target_size = bdrv_getlength(bs); - if (target_size < 0) { - return target_size; - } - - for (;;) { - bytes = MIN(target_size - offset, BDRV_REQUEST_MAX_BYTES); - if (bytes <= 0) { - return 0; - } - ret = bdrv_block_status(bs, offset, bytes, &bytes, NULL, NULL); - if (ret < 0) { - return ret; - } - if (ret & BDRV_BLOCK_ZERO) { - offset += bytes; - continue; - } - ret = bdrv_pwrite_zeroes(child, offset, bytes, flags); - if (ret < 0) { - return ret; - } - offset += bytes; - } -} - -int bdrv_preadv(BdrvChild *child, int64_t offset, QEMUIOVector *qiov) -{ - int ret; - - ret = bdrv_prwv_co(child, offset, qiov, false, 0); - if (ret < 0) { - return ret; - } - - return qiov->size; -} - -/* See bdrv_pwrite() for the return codes */ -int bdrv_pread(BdrvChild *child, int64_t offset, void *buf, int bytes) -{ - QEMUIOVector qiov = QEMU_IOVEC_INIT_BUF(qiov, buf, bytes); - - if (bytes < 0) { - return -EINVAL; - } - - return bdrv_preadv(child, offset, &qiov); -} - -int bdrv_pwritev(BdrvChild *child, int64_t offset, QEMUIOVector *qiov) -{ - int ret; - - ret = bdrv_prwv_co(child, offset, qiov, true, 0); - if (ret < 0) { - return ret; - } - - return qiov->size; -} - -/* Return no. of bytes on success or < 0 on error. Important errors are: - -EIO generic I/O error (may happen for all errors) - -ENOMEDIUM No media inserted. - -EINVAL Invalid offset or number of bytes - -EACCES Trying to write a read-only device -*/ -int bdrv_pwrite(BdrvChild *child, int64_t offset, const void *buf, int bytes) -{ - QEMUIOVector qiov = QEMU_IOVEC_INIT_BUF(qiov, buf, bytes); - - if (bytes < 0) { - return -EINVAL; - } - - return bdrv_pwritev(child, offset, &qiov); -} - -/* - * Writes to the file and ensures that no writes are reordered across this - * request (acts as a barrier) - * - * Returns 0 on success, -errno in error cases. - */ -int bdrv_pwrite_sync(BdrvChild *child, int64_t offset, - const void *buf, int count) -{ - int ret; - - ret = bdrv_pwrite(child, offset, buf, count); - if (ret < 0) { - return ret; - } - - ret = bdrv_flush(child->bs); - if (ret < 0) { - return ret; - } - - return 0; -} - typedef struct CoroutineIOCompletion { Coroutine *coroutine; int ret; @@ -2185,6 +2005,187 @@ int coroutine_fn bdrv_co_pwrite_zeroes(BdrvChild *child, int64_t offset, BDRV_REQ_ZERO_WRITE | flags); } +typedef struct RwCo { + BdrvChild *child; + int64_t offset; + QEMUIOVector *qiov; + bool is_write; + int ret; + BdrvRequestFlags flags; +} RwCo; + +static void coroutine_fn bdrv_rw_co_entry(void *opaque) +{ + RwCo *rwco = opaque; + + if (!rwco->is_write) { + rwco->ret = bdrv_co_preadv(rwco->child, rwco->offset, + rwco->qiov->size, rwco->qiov, + rwco->flags); + } else { + rwco->ret = bdrv_co_pwritev(rwco->child, rwco->offset, + rwco->qiov->size, rwco->qiov, + rwco->flags); + } + aio_wait_kick(); +} + +/* + * Process a vectored synchronous request using coroutines + */ +static int bdrv_prwv_co(BdrvChild *child, int64_t offset, + QEMUIOVector *qiov, bool is_write, + BdrvRequestFlags flags) +{ + Coroutine *co; + RwCo rwco = { + .child = child, + .offset = offset, + .qiov = qiov, + .is_write = is_write, + .ret = NOT_DONE, + .flags = flags, + }; + + if (qemu_in_coroutine()) { + /* Fast-path if already in coroutine context */ + bdrv_rw_co_entry(&rwco); + } else { + co = qemu_coroutine_create(bdrv_rw_co_entry, &rwco); + bdrv_coroutine_enter(child->bs, co); + BDRV_POLL_WHILE(child->bs, rwco.ret == NOT_DONE); + } + return rwco.ret; +} + +int bdrv_pwrite_zeroes(BdrvChild *child, int64_t offset, + int bytes, BdrvRequestFlags flags) +{ + QEMUIOVector qiov = QEMU_IOVEC_INIT_BUF(qiov, NULL, bytes); + + return bdrv_prwv_co(child, offset, &qiov, true, + BDRV_REQ_ZERO_WRITE | flags); +} + +/* See bdrv_pwrite() for the return codes */ +int bdrv_pread(BdrvChild *child, int64_t offset, void *buf, int bytes) +{ + QEMUIOVector qiov = QEMU_IOVEC_INIT_BUF(qiov, buf, bytes); + + if (bytes < 0) { + return -EINVAL; + } + + return bdrv_preadv(child, offset, &qiov); +} + +int bdrv_pwritev(BdrvChild *child, int64_t offset, QEMUIOVector *qiov) +{ + int ret; + + ret = bdrv_prwv_co(child, offset, qiov, true, 0); + if (ret < 0) { + return ret; + } + + return qiov->size; +} + +/* + * Return no. of bytes on success or < 0 on error. Important errors are: + * -EIO generic I/O error (may happen for all errors) + * -ENOMEDIUM No media inserted. + * -EINVAL Invalid offset or number of bytes + * -EACCES Trying to write a read-only device + */ +int bdrv_pwrite(BdrvChild *child, int64_t offset, const void *buf, int bytes) +{ + QEMUIOVector qiov = QEMU_IOVEC_INIT_BUF(qiov, buf, bytes); + + if (bytes < 0) { + return -EINVAL; + } + + return bdrv_pwritev(child, offset, &qiov); +} + +/* + * Writes to the file and ensures that no writes are reordered across this + * request (acts as a barrier) + * + * Returns 0 on success, -errno in error cases. + */ +int bdrv_pwrite_sync(BdrvChild *child, int64_t offset, + const void *buf, int count) +{ + int ret; + + ret = bdrv_pwrite(child, offset, buf, count); + if (ret < 0) { + return ret; + } + + ret = bdrv_flush(child->bs); + if (ret < 0) { + return ret; + } + + return 0; +} + +/* + * Completely zero out a block device with the help of bdrv_pwrite_zeroes. + * The operation is sped up by checking the block status and only writing + * zeroes to the device if they currently do not return zeroes. Optional + * flags are passed through to bdrv_pwrite_zeroes (e.g. BDRV_REQ_MAY_UNMAP, + * BDRV_REQ_FUA). + * + * Returns < 0 on error, 0 on success. For error codes see bdrv_write(). + */ +int bdrv_make_zero(BdrvChild *child, BdrvRequestFlags flags) +{ + int ret; + int64_t target_size, bytes, offset = 0; + BlockDriverState *bs = child->bs; + + target_size = bdrv_getlength(bs); + if (target_size < 0) { + return target_size; + } + + for (;;) { + bytes = MIN(target_size - offset, BDRV_REQUEST_MAX_BYTES); + if (bytes <= 0) { + return 0; + } + ret = bdrv_block_status(bs, offset, bytes, &bytes, NULL, NULL); + if (ret < 0) { + return ret; + } + if (ret & BDRV_BLOCK_ZERO) { + offset += bytes; + continue; + } + ret = bdrv_pwrite_zeroes(child, offset, bytes, flags); + if (ret < 0) { + return ret; + } + offset += bytes; + } +} + +int bdrv_preadv(BdrvChild *child, int64_t offset, QEMUIOVector *qiov) +{ + int ret; + + ret = bdrv_prwv_co(child, offset, qiov, false, 0); + if (ret < 0) { + return ret; + } + + return qiov->size; +} + /* * Flush ALL BDSes regardless of if they are reachable via a BlkBackend or not. */ -- 2.21.0