From 0d93ed08454e76fa943f6f71964362296d41b12e Mon Sep 17 00:00:00 2001 From: Vladimir Sementsov-Ogievskiy Date: Mon, 18 Feb 2019 17:09:11 +0300 Subject: [PATCH] block/io: use qemu_iovec_init_buf Use new qemu_iovec_init_buf() instead of qemu_iovec_init_external( ... , 1), which simplifies the code. While being here, use qemu_try_blockalign0 as well. Signed-off-by: Vladimir Sementsov-Ogievskiy Reviewed-by: Eric Blake Reviewed-by: Stefan Hajnoczi Message-id: 20190218140926.333779-3-vsementsov@virtuozzo.com Message-Id: <20190218140926.333779-3-vsementsov@virtuozzo.com> Signed-off-by: Stefan Hajnoczi --- block/io.c | 89 ++++++++++++------------------------------------------ 1 file changed, 20 insertions(+), 69 deletions(-) diff --git a/block/io.c b/block/io.c index 213ca03d8d..2ba603c7bc 100644 --- a/block/io.c +++ b/block/io.c @@ -843,17 +843,13 @@ static int bdrv_prwv_co(BdrvChild *child, int64_t offset, static int bdrv_rw_co(BdrvChild *child, int64_t sector_num, uint8_t *buf, int nb_sectors, bool is_write, BdrvRequestFlags flags) { - QEMUIOVector qiov; - struct iovec iov = { - .iov_base = (void *)buf, - .iov_len = nb_sectors * BDRV_SECTOR_SIZE, - }; + QEMUIOVector qiov = QEMU_IOVEC_INIT_BUF(qiov, buf, + nb_sectors * BDRV_SECTOR_SIZE); if (nb_sectors < 0 || nb_sectors > BDRV_REQUEST_MAX_SECTORS) { return -EINVAL; } - qemu_iovec_init_external(&qiov, &iov, 1); return bdrv_prwv_co(child, sector_num << BDRV_SECTOR_BITS, &qiov, is_write, flags); } @@ -880,13 +876,8 @@ int bdrv_write(BdrvChild *child, int64_t sector_num, int bdrv_pwrite_zeroes(BdrvChild *child, int64_t offset, int bytes, BdrvRequestFlags flags) { - QEMUIOVector qiov; - struct iovec iov = { - .iov_base = NULL, - .iov_len = bytes, - }; + QEMUIOVector qiov = QEMU_IOVEC_INIT_BUF(qiov, NULL, bytes); - qemu_iovec_init_external(&qiov, &iov, 1); return bdrv_prwv_co(child, offset, &qiov, true, BDRV_REQ_ZERO_WRITE | flags); } @@ -950,17 +941,12 @@ int bdrv_preadv(BdrvChild *child, int64_t offset, QEMUIOVector *qiov) int bdrv_pread(BdrvChild *child, int64_t offset, void *buf, int bytes) { - QEMUIOVector qiov; - struct iovec iov = { - .iov_base = (void *)buf, - .iov_len = bytes, - }; + QEMUIOVector qiov = QEMU_IOVEC_INIT_BUF(qiov, buf, bytes); if (bytes < 0) { return -EINVAL; } - qemu_iovec_init_external(&qiov, &iov, 1); return bdrv_preadv(child, offset, &qiov); } @@ -978,17 +964,12 @@ int bdrv_pwritev(BdrvChild *child, int64_t offset, QEMUIOVector *qiov) int bdrv_pwrite(BdrvChild *child, int64_t offset, const void *buf, int bytes) { - QEMUIOVector qiov; - struct iovec iov = { - .iov_base = (void *) buf, - .iov_len = bytes, - }; + QEMUIOVector qiov = QEMU_IOVEC_INIT_BUF(qiov, buf, bytes); if (bytes < 0) { return -EINVAL; } - qemu_iovec_init_external(&qiov, &iov, 1); return bdrv_pwritev(child, offset, &qiov); } @@ -1165,7 +1146,6 @@ static int coroutine_fn bdrv_co_do_copy_on_readv(BdrvChild *child, void *bounce_buffer; BlockDriver *drv = bs->drv; - struct iovec iov; QEMUIOVector local_qiov; int64_t cluster_offset; int64_t cluster_bytes; @@ -1230,9 +1210,8 @@ static int coroutine_fn bdrv_co_do_copy_on_readv(BdrvChild *child, if (ret <= 0) { /* Must copy-on-read; use the bounce buffer */ - iov.iov_base = bounce_buffer; - iov.iov_len = pnum = MIN(pnum, MAX_BOUNCE_BUFFER); - qemu_iovec_init_external(&local_qiov, &iov, 1); + pnum = MIN(pnum, MAX_BOUNCE_BUFFER); + qemu_iovec_init_buf(&local_qiov, bounce_buffer, pnum); ret = bdrv_driver_preadv(bs, cluster_offset, pnum, &local_qiov, 0); @@ -1477,7 +1456,7 @@ static int coroutine_fn bdrv_co_do_pwrite_zeroes(BlockDriverState *bs, { BlockDriver *drv = bs->drv; QEMUIOVector qiov; - struct iovec iov = {0}; + void *buf = NULL; int ret = 0; bool need_flush = false; int head = 0; @@ -1547,16 +1526,14 @@ static int coroutine_fn bdrv_co_do_pwrite_zeroes(BlockDriverState *bs, need_flush = true; } num = MIN(num, max_transfer); - iov.iov_len = num; - if (iov.iov_base == NULL) { - iov.iov_base = qemu_try_blockalign(bs, num); - if (iov.iov_base == NULL) { + if (buf == NULL) { + buf = qemu_try_blockalign0(bs, num); + if (buf == NULL) { ret = -ENOMEM; goto fail; } - memset(iov.iov_base, 0, num); } - qemu_iovec_init_external(&qiov, &iov, 1); + qemu_iovec_init_buf(&qiov, buf, num); ret = bdrv_driver_pwritev(bs, offset, num, &qiov, write_flags); @@ -1564,8 +1541,8 @@ static int coroutine_fn bdrv_co_do_pwrite_zeroes(BlockDriverState *bs, * all future requests. */ if (num < max_transfer) { - qemu_vfree(iov.iov_base); - iov.iov_base = NULL; + qemu_vfree(buf); + buf = NULL; } } @@ -1577,7 +1554,7 @@ fail: if (ret == 0 && need_flush) { ret = bdrv_co_flush(bs); } - qemu_vfree(iov.iov_base); + qemu_vfree(buf); return ret; } @@ -1763,7 +1740,6 @@ static int coroutine_fn bdrv_co_do_zero_pwritev(BdrvChild *child, BlockDriverState *bs = child->bs; uint8_t *buf = NULL; QEMUIOVector local_qiov; - struct iovec iov; uint64_t align = bs->bl.request_alignment; unsigned int head_padding_bytes, tail_padding_bytes; int ret = 0; @@ -1775,11 +1751,7 @@ static int coroutine_fn bdrv_co_do_zero_pwritev(BdrvChild *child, assert(flags & BDRV_REQ_ZERO_WRITE); if (head_padding_bytes || tail_padding_bytes) { buf = qemu_blockalign(bs, align); - iov = (struct iovec) { - .iov_base = buf, - .iov_len = align, - }; - qemu_iovec_init_external(&local_qiov, &iov, 1); + qemu_iovec_init_buf(&local_qiov, buf, align); } if (head_padding_bytes) { uint64_t zero_bytes = MIN(bytes, align - head_padding_bytes); @@ -1885,17 +1857,12 @@ int coroutine_fn bdrv_co_pwritev(BdrvChild *child, if (offset & (align - 1)) { QEMUIOVector head_qiov; - struct iovec head_iov; mark_request_serialising(&req, align); wait_serialising_requests(&req); head_buf = qemu_blockalign(bs, align); - head_iov = (struct iovec) { - .iov_base = head_buf, - .iov_len = align, - }; - qemu_iovec_init_external(&head_qiov, &head_iov, 1); + qemu_iovec_init_buf(&head_qiov, head_buf, align); bdrv_debug_event(bs, BLKDBG_PWRITEV_RMW_HEAD); ret = bdrv_aligned_preadv(child, &req, offset & ~(align - 1), align, @@ -1924,7 +1891,6 @@ int coroutine_fn bdrv_co_pwritev(BdrvChild *child, if ((offset + bytes) & (align - 1)) { QEMUIOVector tail_qiov; - struct iovec tail_iov; size_t tail_bytes; bool waited; @@ -1933,11 +1899,7 @@ int coroutine_fn bdrv_co_pwritev(BdrvChild *child, assert(!waited || !use_local_qiov); tail_buf = qemu_blockalign(bs, align); - tail_iov = (struct iovec) { - .iov_base = tail_buf, - .iov_len = align, - }; - qemu_iovec_init_external(&tail_qiov, &tail_iov, 1); + qemu_iovec_init_buf(&tail_qiov, tail_buf, align); bdrv_debug_event(bs, BLKDBG_PWRITEV_RMW_TAIL); ret = bdrv_aligned_preadv(child, &req, (offset + bytes) & ~(align - 1), @@ -2468,15 +2430,9 @@ bdrv_rw_vmstate(BlockDriverState *bs, QEMUIOVector *qiov, int64_t pos, int bdrv_save_vmstate(BlockDriverState *bs, const uint8_t *buf, int64_t pos, int size) { - QEMUIOVector qiov; - struct iovec iov = { - .iov_base = (void *) buf, - .iov_len = size, - }; + QEMUIOVector qiov = QEMU_IOVEC_INIT_BUF(qiov, buf, size); int ret; - qemu_iovec_init_external(&qiov, &iov, 1); - ret = bdrv_writev_vmstate(bs, &qiov, pos); if (ret < 0) { return ret; @@ -2493,14 +2449,9 @@ int bdrv_writev_vmstate(BlockDriverState *bs, QEMUIOVector *qiov, int64_t pos) int bdrv_load_vmstate(BlockDriverState *bs, uint8_t *buf, int64_t pos, int size) { - QEMUIOVector qiov; - struct iovec iov = { - .iov_base = buf, - .iov_len = size, - }; + QEMUIOVector qiov = QEMU_IOVEC_INIT_BUF(qiov, buf, size); int ret; - qemu_iovec_init_external(&qiov, &iov, 1); ret = bdrv_readv_vmstate(bs, &qiov, pos); if (ret < 0) { return ret;