From 1581a70ddd0cd71a8520027d7136ed1e2f6bd19b Mon Sep 17 00:00:00 2001 From: Emanuele Giuseppe Esposito Date: Thu, 3 Mar 2022 10:16:09 -0500 Subject: [PATCH] block/coroutines: I/O and "I/O or GS" API block coroutines functions run in different aiocontext, and are not protected by the BQL. Therefore are I/O. On the other side, generated_co_wrapper functions use BDRV_POLL_WHILE, meaning the caller can either be the main loop or a specific iothread. Signed-off-by: Emanuele Giuseppe Esposito Message-Id: <20220303151616.325444-25-eesposit@redhat.com> Signed-off-by: Kevin Wolf --- block.c | 2 ++ block/block-backend.c | 6 ++++ block/coroutines.h | 81 +++++++++++++++++++++++++++---------------- block/io.c | 3 ++ block/nbd.c | 1 + 5 files changed, 64 insertions(+), 29 deletions(-) diff --git a/block.c b/block.c index d3b97c3569..b91f9b2d11 100644 --- a/block.c +++ b/block.c @@ -5454,6 +5454,7 @@ fail: int coroutine_fn bdrv_co_check(BlockDriverState *bs, BdrvCheckResult *res, BdrvCheckMode fix) { + IO_CODE(); if (bs->drv == NULL) { return -ENOMEDIUM; } @@ -6663,6 +6664,7 @@ int bdrv_activate(BlockDriverState *bs, Error **errp) int coroutine_fn bdrv_co_invalidate_cache(BlockDriverState *bs, Error **errp) { Error *local_err = NULL; + IO_CODE(); assert(!(bs->open_flags & BDRV_O_INACTIVE)); diff --git a/block/block-backend.c b/block/block-backend.c index bf77c4a8fa..e0e1aff4b1 100644 --- a/block/block-backend.c +++ b/block/block-backend.c @@ -1290,6 +1290,7 @@ blk_co_do_preadv(BlockBackend *blk, int64_t offset, int64_t bytes, { int ret; BlockDriverState *bs; + IO_CODE(); blk_wait_while_drained(blk); @@ -1337,6 +1338,7 @@ blk_co_do_pwritev_part(BlockBackend *blk, int64_t offset, int64_t bytes, { int ret; BlockDriverState *bs; + IO_CODE(); blk_wait_while_drained(blk); @@ -1656,6 +1658,8 @@ void blk_aio_cancel_async(BlockAIOCB *acb) int coroutine_fn blk_co_do_ioctl(BlockBackend *blk, unsigned long int req, void *buf) { + IO_CODE(); + blk_wait_while_drained(blk); if (!blk_is_available(blk)) { @@ -1699,6 +1703,7 @@ int coroutine_fn blk_co_do_pdiscard(BlockBackend *blk, int64_t offset, int64_t bytes) { int ret; + IO_CODE(); blk_wait_while_drained(blk); @@ -1757,6 +1762,7 @@ int blk_pdiscard(BlockBackend *blk, int64_t offset, int64_t bytes) int coroutine_fn blk_co_do_flush(BlockBackend *blk) { blk_wait_while_drained(blk); + IO_CODE(); if (!blk_is_available(blk)) { return -ENOMEDIUM; diff --git a/block/coroutines.h b/block/coroutines.h index c8c14a29c8..b293e943c8 100644 --- a/block/coroutines.h +++ b/block/coroutines.h @@ -30,17 +30,17 @@ /* For blk_bs() in generated block/block-gen.c */ #include "sysemu/block-backend.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_check(BlockDriverState *bs, BdrvCheckResult *res, BdrvCheckMode fix); int coroutine_fn bdrv_co_invalidate_cache(BlockDriverState *bs, Error **errp); -int generated_co_wrapper -bdrv_preadv(BdrvChild *child, int64_t offset, unsigned int bytes, - QEMUIOVector *qiov, BdrvRequestFlags flags); -int generated_co_wrapper -bdrv_pwritev(BdrvChild *child, int64_t offset, unsigned int bytes, - QEMUIOVector *qiov, BdrvRequestFlags flags); - int coroutine_fn bdrv_co_common_block_status_above(BlockDriverState *bs, BlockDriverState *base, @@ -52,6 +52,51 @@ bdrv_co_common_block_status_above(BlockDriverState *bs, int64_t *map, BlockDriverState **file, int *depth); + +int coroutine_fn bdrv_co_readv_vmstate(BlockDriverState *bs, + QEMUIOVector *qiov, int64_t pos); +int coroutine_fn bdrv_co_writev_vmstate(BlockDriverState *bs, + QEMUIOVector *qiov, int64_t pos); + +int coroutine_fn +nbd_co_do_establish_connection(BlockDriverState *bs, Error **errp); + + +int coroutine_fn +blk_co_do_preadv(BlockBackend *blk, int64_t offset, int64_t bytes, + QEMUIOVector *qiov, BdrvRequestFlags flags); + + +int coroutine_fn +blk_co_do_pwritev_part(BlockBackend *blk, int64_t offset, int64_t bytes, + QEMUIOVector *qiov, size_t qiov_offset, + BdrvRequestFlags flags); + +int coroutine_fn +blk_co_do_ioctl(BlockBackend *blk, unsigned long int req, void *buf); + +int coroutine_fn +blk_co_do_pdiscard(BlockBackend *blk, int64_t offset, int64_t bytes); + +int coroutine_fn blk_co_do_flush(BlockBackend *blk); + + +/* + * "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. + */ + +int generated_co_wrapper +bdrv_preadv(BdrvChild *child, int64_t offset, unsigned int bytes, + QEMUIOVector *qiov, BdrvRequestFlags flags); + +int generated_co_wrapper +bdrv_pwritev(BdrvChild *child, int64_t offset, unsigned int bytes, + QEMUIOVector *qiov, BdrvRequestFlags flags); + int generated_co_wrapper bdrv_common_block_status_above(BlockDriverState *bs, BlockDriverState *base, @@ -63,46 +108,24 @@ bdrv_common_block_status_above(BlockDriverState *bs, int64_t *map, BlockDriverState **file, int *depth); - -int coroutine_fn bdrv_co_readv_vmstate(BlockDriverState *bs, - QEMUIOVector *qiov, int64_t pos); -int coroutine_fn bdrv_co_writev_vmstate(BlockDriverState *bs, - QEMUIOVector *qiov, int64_t pos); - int generated_co_wrapper nbd_do_establish_connection(BlockDriverState *bs, Error **errp); -int coroutine_fn -nbd_co_do_establish_connection(BlockDriverState *bs, Error **errp); - int generated_co_wrapper blk_do_preadv(BlockBackend *blk, int64_t offset, int64_t bytes, QEMUIOVector *qiov, BdrvRequestFlags flags); -int coroutine_fn -blk_co_do_preadv(BlockBackend *blk, int64_t offset, int64_t bytes, - QEMUIOVector *qiov, BdrvRequestFlags flags); - int generated_co_wrapper blk_do_pwritev_part(BlockBackend *blk, int64_t offset, int64_t bytes, QEMUIOVector *qiov, size_t qiov_offset, BdrvRequestFlags flags); -int coroutine_fn -blk_co_do_pwritev_part(BlockBackend *blk, int64_t offset, int64_t bytes, - QEMUIOVector *qiov, size_t qiov_offset, - BdrvRequestFlags flags); int generated_co_wrapper blk_do_ioctl(BlockBackend *blk, unsigned long int req, void *buf); -int coroutine_fn -blk_co_do_ioctl(BlockBackend *blk, unsigned long int req, void *buf); int generated_co_wrapper blk_do_pdiscard(BlockBackend *blk, int64_t offset, int64_t bytes); -int coroutine_fn -blk_co_do_pdiscard(BlockBackend *blk, int64_t offset, int64_t bytes); int generated_co_wrapper blk_do_flush(BlockBackend *blk); -int coroutine_fn blk_co_do_flush(BlockBackend *blk); #endif /* BLOCK_COROUTINES_INT_H */ diff --git a/block/io.c b/block/io.c index 6a0bad10a3..4b1d97c7da 100644 --- a/block/io.c +++ b/block/io.c @@ -2678,6 +2678,7 @@ bdrv_co_common_block_status_above(BlockDriverState *bs, BlockDriverState *p; int64_t eof = 0; int dummy; + IO_CODE(); assert(!include_base || base); /* Can't include NULL base */ @@ -2867,6 +2868,7 @@ bdrv_co_readv_vmstate(BlockDriverState *bs, QEMUIOVector *qiov, int64_t pos) BlockDriver *drv = bs->drv; BlockDriverState *child_bs = bdrv_primary_bs(bs); int ret; + IO_CODE(); ret = bdrv_check_qiov_request(pos, qiov->size, qiov, 0, NULL); if (ret < 0) { @@ -2898,6 +2900,7 @@ bdrv_co_writev_vmstate(BlockDriverState *bs, QEMUIOVector *qiov, int64_t pos) BlockDriver *drv = bs->drv; BlockDriverState *child_bs = bdrv_primary_bs(bs); int ret; + IO_CODE(); ret = bdrv_check_qiov_request(pos, qiov->size, qiov, 0, NULL); if (ret < 0) { diff --git a/block/nbd.c b/block/nbd.c index 5853d85d60..146d25660e 100644 --- a/block/nbd.c +++ b/block/nbd.c @@ -313,6 +313,7 @@ int coroutine_fn nbd_co_do_establish_connection(BlockDriverState *bs, BDRVNBDState *s = (BDRVNBDState *)bs->opaque; int ret; bool blocking = nbd_client_connecting_wait(s); + IO_CODE(); assert(!s->ioc);