From 6904e1d2aad513cb635d79b6654b02ca0039c5ca Mon Sep 17 00:00:00 2001 From: Kevin Wolf Date: Tue, 14 Feb 2012 11:14:24 +0100 Subject: [PATCH 59/99] block: Use bdrv_co_* instead of synchronous versions in coroutines RH-Author: Kevin Wolf Message-id: <1329218101-24213-60-git-send-email-kwolf@redhat.com> Patchwork-id: 37249 O-Subject: [RHEL-6.3 qemu-kvm PATCH v2 59/96] block: Use bdrv_co_* instead of synchronous versions in coroutines Bugzilla: 783950 RH-Acked-by: Paolo Bonzini RH-Acked-by: Marcelo Tosatti RH-Acked-by: Laszlo Ersek Bugzilla: 783950 If we're already in a coroutine, there is no reason to use the synchronous version of block layer functions when a coroutine one exists. This makes bdrv_read/write/flush use bdrv_co_* when used inside a coroutine. Signed-off-by: Kevin Wolf (cherry picked from commit e7a8a7837a964e0fe327e6ef8dde02c6a53dd14a) --- block.c | 56 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 files changed, 56 insertions(+), 0 deletions(-) Signed-off-by: Michal Novotny --- block.c | 56 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 files changed, 56 insertions(+), 0 deletions(-) diff --git a/block.c b/block.c index ad19c57..91972ef 100644 --- a/block.c +++ b/block.c @@ -71,6 +71,7 @@ static int coroutine_fn bdrv_co_readv_em(BlockDriverState *bs, static int coroutine_fn bdrv_co_writev_em(BlockDriverState *bs, int64_t sector_num, int nb_sectors, QEMUIOVector *iov); +static int coroutine_fn bdrv_co_flush_em(BlockDriverState *bs); static QTAILQ_HEAD(, BlockDriverState) bdrv_states = QTAILQ_HEAD_INITIALIZER(bdrv_states); @@ -983,6 +984,17 @@ static int bdrv_check_request(BlockDriverState *bs, int64_t sector_num, nb_sectors * BDRV_SECTOR_SIZE); } +static inline bool bdrv_has_async_rw(BlockDriver *drv) +{ + return drv->bdrv_co_readv != bdrv_co_readv_em + || drv->bdrv_aio_readv != bdrv_aio_readv_em; +} + +static inline bool bdrv_has_async_flush(BlockDriver *drv) +{ + return drv->bdrv_aio_flush != bdrv_aio_flush_em; +} + /* return < 0 if error. See bdrv_write() for the return codes */ int bdrv_read(BlockDriverState *bs, int64_t sector_num, uint8_t *buf, int nb_sectors) @@ -991,6 +1003,18 @@ int bdrv_read(BlockDriverState *bs, int64_t sector_num, if (!drv) return -ENOMEDIUM; + + if (bdrv_has_async_rw(drv) && qemu_in_coroutine()) { + QEMUIOVector qiov; + struct iovec iov = { + .iov_base = (void *)buf, + .iov_len = nb_sectors * BDRV_SECTOR_SIZE, + }; + + qemu_iovec_init_external(&qiov, &iov, 1); + return bdrv_co_readv(bs, sector_num, nb_sectors, &qiov); + } + if (bdrv_check_request(bs, sector_num, nb_sectors)) return -EIO; @@ -1029,8 +1053,21 @@ int bdrv_write(BlockDriverState *bs, int64_t sector_num, const uint8_t *buf, int nb_sectors) { BlockDriver *drv = bs->drv; + if (!bs->drv) return -ENOMEDIUM; + + if (bdrv_has_async_rw(drv) && qemu_in_coroutine()) { + QEMUIOVector qiov; + struct iovec iov = { + .iov_base = (void *)buf, + .iov_len = nb_sectors * BDRV_SECTOR_SIZE, + }; + + qemu_iovec_init_external(&qiov, &iov, 1); + return bdrv_co_writev(bs, sector_num, nb_sectors, &qiov); + } + if (bs->read_only) return -EACCES; if (bdrv_check_request(bs, sector_num, nb_sectors)) @@ -1542,6 +1579,10 @@ int bdrv_flush(BlockDriverState *bs) return 0; } + if (bs->drv && bdrv_has_async_flush(bs->drv) && qemu_in_coroutine()) { + return bdrv_co_flush_em(bs); + } + if (bs->drv && bs->drv->bdrv_flush) { return bs->drv->bdrv_flush(bs); } @@ -2853,6 +2894,21 @@ static int coroutine_fn bdrv_co_writev_em(BlockDriverState *bs, return bdrv_co_io_em(bs, sector_num, nb_sectors, iov, true); } +static int coroutine_fn bdrv_co_flush_em(BlockDriverState *bs) +{ + CoroutineIOCompletion co = { + .coroutine = qemu_coroutine_self(), + }; + BlockDriverAIOCB *acb; + + acb = bdrv_aio_flush(bs, bdrv_co_io_em_complete, &co); + if (!acb) { + return -EIO; + } + qemu_coroutine_yield(); + return co.ret; +} + /**************************************************************/ /* removable device support */ -- 1.7.7.5