From: Emanuele Giuseppe Esposito <eespo...@redhat.com> bdrv_is_inserted() is categorized as an I/O function, and it currently doesn't run in a coroutine. We should let it take a graph rdlock since it traverses the block nodes graph, which however is only possible in a coroutine.
Therefore turn it into a co_wrapper to move the actual function into a coroutine where the lock can be taken. At the same time, add also blk_is_inserted as co_wrapper_mixed, since it is called in both coroutine and non-coroutine contexts. Because now this function creates a new coroutine and polls, we need to take the AioContext lock where it is missing, for the only reason that internally c_w_mixed_bdrv_rdlock calls AIO_WAIT_WHILE and it expects to release the AioContext lock. Once the rwlock is ultimated and placed in every place it needs to be, we will poll using AIO_WAIT_WHILE_UNLOCKED and remove the AioContext lock. Signed-off-by: Emanuele Giuseppe Esposito <eespo...@redhat.com> Signed-off-by: Kevin Wolf <kw...@redhat.com> --- include/block/block-io.h | 5 ++++- include/block/block_int-common.h | 2 +- include/sysemu/block-backend-io.h | 5 ++++- block.c | 8 ++++---- block/block-backend.c | 4 ++-- block/file-posix.c | 8 ++++---- block/io.c | 12 ++++++------ blockdev.c | 8 +++++++- 8 files changed, 32 insertions(+), 20 deletions(-) diff --git a/include/block/block-io.h b/include/block/block-io.h index 3bf201f7f4..fe031360c4 100644 --- a/include/block/block-io.h +++ b/include/block/block-io.h @@ -133,7 +133,10 @@ bool bdrv_is_read_only(BlockDriverState *bs); bool bdrv_is_writable(BlockDriverState *bs); bool bdrv_is_sg(BlockDriverState *bs); int bdrv_get_flags(BlockDriverState *bs); -bool bdrv_is_inserted(BlockDriverState *bs); + +bool coroutine_fn bdrv_co_is_inserted(BlockDriverState *bs); +bool co_wrapper bdrv_is_inserted(BlockDriverState *bs); + void bdrv_lock_medium(BlockDriverState *bs, bool locked); void bdrv_eject(BlockDriverState *bs, bool eject_flag); const char *bdrv_get_format_name(BlockDriverState *bs); diff --git a/include/block/block_int-common.h b/include/block/block_int-common.h index 253df92509..e6229c64e6 100644 --- a/include/block/block_int-common.h +++ b/include/block/block_int-common.h @@ -708,7 +708,7 @@ struct BlockDriver { BlockDriverState *bs, QEMUIOVector *qiov, int64_t pos); /* removable device specific */ - bool (*bdrv_is_inserted)(BlockDriverState *bs); + bool coroutine_fn (*bdrv_co_is_inserted)(BlockDriverState *bs); void (*bdrv_eject)(BlockDriverState *bs, bool eject_flag); void (*bdrv_lock_medium)(BlockDriverState *bs, bool locked); diff --git a/include/sysemu/block-backend-io.h b/include/sysemu/block-backend-io.h index d8cc8d74f5..4358fc6476 100644 --- a/include/sysemu/block-backend-io.h +++ b/include/sysemu/block-backend-io.h @@ -53,7 +53,10 @@ BlockAIOCB *blk_aio_ioctl(BlockBackend *blk, unsigned long int req, void *buf, void blk_inc_in_flight(BlockBackend *blk); void blk_dec_in_flight(BlockBackend *blk); -bool blk_is_inserted(BlockBackend *blk); + +bool coroutine_fn blk_co_is_inserted(BlockBackend *blk); +bool co_wrapper_mixed blk_is_inserted(BlockBackend *blk); + bool blk_is_available(BlockBackend *blk); void blk_lock_medium(BlockBackend *blk, bool locked); void blk_eject(BlockBackend *blk, bool eject_flag); diff --git a/block.c b/block.c index 9c2ac757e4..e89844557b 100644 --- a/block.c +++ b/block.c @@ -6781,7 +6781,7 @@ out: /** * Return TRUE if the media is present */ -bool bdrv_is_inserted(BlockDriverState *bs) +bool coroutine_fn bdrv_co_is_inserted(BlockDriverState *bs) { BlockDriver *drv = bs->drv; BdrvChild *child; @@ -6790,11 +6790,11 @@ bool bdrv_is_inserted(BlockDriverState *bs) if (!drv) { return false; } - if (drv->bdrv_is_inserted) { - return drv->bdrv_is_inserted(bs); + if (drv->bdrv_co_is_inserted) { + return drv->bdrv_co_is_inserted(bs); } QLIST_FOREACH(child, &bs->children, next) { - if (!bdrv_is_inserted(child->bs)) { + if (!bdrv_co_is_inserted(child->bs)) { return false; } } diff --git a/block/block-backend.c b/block/block-backend.c index 71c7ef4004..6e3b3b9fe8 100644 --- a/block/block-backend.c +++ b/block/block-backend.c @@ -1983,12 +1983,12 @@ void blk_activate(BlockBackend *blk, Error **errp) bdrv_activate(bs, errp); } -bool blk_is_inserted(BlockBackend *blk) +bool coroutine_fn blk_co_is_inserted(BlockBackend *blk) { BlockDriverState *bs = blk_bs(blk); IO_CODE(); - return bs && bdrv_is_inserted(bs); + return bs && bdrv_co_is_inserted(bs); } bool blk_is_available(BlockBackend *blk) diff --git a/block/file-posix.c b/block/file-posix.c index dd1b8ec52a..b29cd02b30 100644 --- a/block/file-posix.c +++ b/block/file-posix.c @@ -3761,7 +3761,7 @@ out: return prio; } -static bool cdrom_is_inserted(BlockDriverState *bs) +static bool coroutine_fn cdrom_co_is_inserted(BlockDriverState *bs) { BDRVRawState *s = bs->opaque; int ret; @@ -3828,7 +3828,7 @@ static BlockDriver bdrv_host_cdrom = { = raw_get_allocated_file_size, /* removable device support */ - .bdrv_is_inserted = cdrom_is_inserted, + .bdrv_co_is_inserted = cdrom_co_is_inserted, .bdrv_eject = cdrom_eject, .bdrv_lock_medium = cdrom_lock_medium, @@ -3887,7 +3887,7 @@ static int cdrom_reopen(BlockDriverState *bs) return 0; } -static bool cdrom_is_inserted(BlockDriverState *bs) +static bool coroutine_fn cdrom_co_is_inserted(BlockDriverState *bs) { return raw_getlength(bs) > 0; } @@ -3958,7 +3958,7 @@ static BlockDriver bdrv_host_cdrom = { = raw_get_allocated_file_size, /* removable device support */ - .bdrv_is_inserted = cdrom_is_inserted, + .bdrv_co_is_inserted = cdrom_co_is_inserted, .bdrv_eject = cdrom_eject, .bdrv_lock_medium = cdrom_lock_medium, }; diff --git a/block/io.c b/block/io.c index 32c744d546..03becd32d2 100644 --- a/block/io.c +++ b/block/io.c @@ -1621,7 +1621,7 @@ int coroutine_fn bdrv_co_preadv_part(BdrvChild *child, trace_bdrv_co_preadv_part(bs, offset, bytes, flags); - if (!bdrv_is_inserted(bs)) { + if (!bdrv_co_is_inserted(bs)) { return -ENOMEDIUM; } @@ -2066,7 +2066,7 @@ int coroutine_fn bdrv_co_pwritev_part(BdrvChild *child, trace_bdrv_co_pwritev_part(child->bs, offset, bytes, flags); - if (!bdrv_is_inserted(bs)) { + if (!bdrv_co_is_inserted(bs)) { return -ENOMEDIUM; } @@ -2834,7 +2834,7 @@ int coroutine_fn bdrv_co_flush(BlockDriverState *bs) bdrv_inc_in_flight(bs); - if (!bdrv_is_inserted(bs) || bdrv_is_read_only(bs) || + if (!bdrv_co_is_inserted(bs) || bdrv_is_read_only(bs) || bdrv_is_sg(bs)) { goto early_exit; } @@ -2958,7 +2958,7 @@ int coroutine_fn bdrv_co_pdiscard(BdrvChild *child, int64_t offset, BlockDriverState *bs = child->bs; IO_CODE(); - if (!bs || !bs->drv || !bdrv_is_inserted(bs)) { + if (!bs || !bs->drv || !bdrv_co_is_inserted(bs)) { return -ENOMEDIUM; } @@ -3240,7 +3240,7 @@ static int coroutine_fn bdrv_co_copy_range_internal( assert(!(read_flags & BDRV_REQ_NO_WAIT)); assert(!(write_flags & BDRV_REQ_NO_WAIT)); - if (!dst || !dst->bs || !bdrv_is_inserted(dst->bs)) { + if (!dst || !dst->bs || !bdrv_co_is_inserted(dst->bs)) { return -ENOMEDIUM; } ret = bdrv_check_request32(dst_offset, bytes, NULL, 0); @@ -3251,7 +3251,7 @@ static int coroutine_fn bdrv_co_copy_range_internal( return bdrv_co_pwrite_zeroes(dst, dst_offset, bytes, write_flags); } - if (!src || !src->bs || !bdrv_is_inserted(src->bs)) { + if (!src || !src->bs || !bdrv_co_is_inserted(src->bs)) { return -ENOMEDIUM; } ret = bdrv_check_request32(src_offset, bytes, NULL, 0); diff --git a/blockdev.c b/blockdev.c index ebf952cd21..ec9271ce49 100644 --- a/blockdev.c +++ b/blockdev.c @@ -1023,6 +1023,7 @@ fail: static BlockDriverState *qmp_get_root_bs(const char *name, Error **errp) { BlockDriverState *bs; + AioContext *aio_context; bs = bdrv_lookup_bs(name, name, errp); if (bs == NULL) { @@ -1034,11 +1035,16 @@ static BlockDriverState *qmp_get_root_bs(const char *name, Error **errp) return NULL; } + aio_context = bdrv_get_aio_context(bs); + aio_context_acquire(aio_context); + if (!bdrv_is_inserted(bs)) { error_setg(errp, "Device has no medium"); - return NULL; + bs = NULL; } + aio_context_release(aio_context); + return bs; } -- 2.38.1