From eb94b81a94bce112e6b206df846c1551aaf6cab6 Mon Sep 17 00:00:00 2001 From: Kevin Wolf Date: Mon, 5 Oct 2020 17:58:55 +0200 Subject: block: Convert 'block_resize' to coroutine block_resize performs some I/O that could potentially take quite some time, so use it as an example for the new 'coroutine': true annotation in the QAPI schema. bdrv_truncate() requires that we're already in the right AioContext for the BlockDriverState if called in coroutine context. So instead of just taking the AioContext lock, move the QMP handler coroutine to the context. Call blk_unref() only after switching back because blk_unref() may only be called in the main thread. Signed-off-by: Kevin Wolf Message-Id: <20201005155855.256490-15-kwolf@redhat.com> Reviewed-by: Stefan Hajnoczi Signed-off-by: Markus Armbruster --- blockdev.c | 16 ++++++++-------- 1 file changed, 8 insertions(+), 8 deletions(-) (limited to 'blockdev.c') diff --git a/blockdev.c b/blockdev.c index a6ae475dac..fe6fb5dc1d 100644 --- a/blockdev.c +++ b/blockdev.c @@ -2449,14 +2449,14 @@ BlockDirtyBitmapSha256 *qmp_x_debug_block_dirty_bitmap_sha256(const char *node, return ret; } -void qmp_block_resize(bool has_device, const char *device, - bool has_node_name, const char *node_name, - int64_t size, Error **errp) +void coroutine_fn qmp_block_resize(bool has_device, const char *device, + bool has_node_name, const char *node_name, + int64_t size, Error **errp) { Error *local_err = NULL; BlockBackend *blk = NULL; BlockDriverState *bs; - AioContext *aio_context; + AioContext *old_ctx; bs = bdrv_lookup_bs(has_device ? device : NULL, has_node_name ? node_name : NULL, @@ -2466,9 +2466,6 @@ void qmp_block_resize(bool has_device, const char *device, return; } - aio_context = bdrv_get_aio_context(bs); - aio_context_acquire(aio_context); - if (size < 0) { error_setg(errp, QERR_INVALID_PARAMETER_VALUE, "size", "a >0 size"); goto out; @@ -2485,12 +2482,15 @@ void qmp_block_resize(bool has_device, const char *device, } bdrv_drained_begin(bs); + old_ctx = bdrv_co_enter(bs); blk_truncate(blk, size, false, PREALLOC_MODE_OFF, 0, errp); + bdrv_co_leave(bs, old_ctx); bdrv_drained_end(bs); out: + bdrv_co_lock(bs); blk_unref(blk); - aio_context_release(aio_context); + bdrv_co_unlock(bs); } void qmp_block_stream(bool has_job_id, const char *job_id, const char *device, -- cgit v1.2.3