751ebd76e6
This patch changes block_job_pause to increase the pause counter and block_job_resume to decrease it. The counter will allow calling block_job_pause/block_job_resume unconditionally on a job when we need to suspend the IO temporarily. From now on, each block_job_resume must be paired with a block_job_pause to keep the counter balanced. The user pause from QMP or HMP will only trigger block_job_pause once until it's resumed, this is achieved by adding a user_paused flag in BlockJob. One occurrence of block_job_resume in mirror_complete is replaced with block_job_enter which does what is necessary. In block_job_cancel, the cancel flag is good enough to instruct coroutines to quit loop, so use block_job_enter to replace the unpaired block_job_resume. Upon block job IO error, user is notified about the entering to the pause state, so this pause belongs to user pause, set the flag accordingly and expect a matching QMP resume. [Extended doc comments as suggested by Paolo Bonzini <pbonzini@redhat.com>. --Stefan] Signed-off-by: Fam Zheng <famz@redhat.com> Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com> Reviewed-by: Paolo Bonzini <pbonzini@redhat.com> Reviewed-by: Alberto Garcia <berto@igalia.com> Message-id: 1428069921-2957-2-git-send-email-famz@redhat.com Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Read the documentation in qemu-doc.html or on http://wiki.qemu-project.org - QEMU team