From: Fam Zheng <famz@redhat.com>
Date: Tue, 24 Jun 2014 12:26:35 +0000 (+0800)
Subject: blockjob: Add block_job_yield()
X-Git-Tag: qemu-xen-4.5.0-rc1^2~9
X-Git-Url: http://xenbits.xensource.com/gitweb?a=commitdiff_plain;h=8e09e2013d82456f074b343d8505b25c0a159dce;p=qemu-upstream-4.5-testing.git

blockjob: Add block_job_yield()

This will unset busy flag and put coroutine to sleep, can be used to
wait for QMP complete/cancel.

Signed-off-by: Fam Zheng <famz@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
(cherry picked from commit dc71ce45ded4e872e25c2de32d5e7a71842b0985)
Signed-off-by: Michael Roth <mdroth@linux.vnet.ibm.com>
---

diff --git a/blockjob.c b/blockjob.c
index b3ce14ceb..bf10f82b7 100644
--- a/blockjob.c
+++ b/blockjob.c
@@ -206,6 +206,20 @@ void block_job_sleep_ns(BlockJob *job, QEMUClockType type, int64_t ns)
     job->busy = true;
 }
 
+void block_job_yield(BlockJob *job)
+{
+    assert(job->busy);
+
+    /* Check cancellation *before* setting busy = false, too!  */
+    if (block_job_is_cancelled(job)) {
+        return;
+    }
+
+    job->busy = false;
+    qemu_coroutine_yield();
+    job->busy = true;
+}
+
 BlockJobInfo *block_job_query(BlockJob *job)
 {
     BlockJobInfo *info = g_new0(BlockJobInfo, 1);
diff --git a/include/block/blockjob.h b/include/block/blockjob.h
index d76de62a4..395be5b6a 100644
--- a/include/block/blockjob.h
+++ b/include/block/blockjob.h
@@ -143,6 +143,14 @@ void *block_job_create(const BlockJobDriver *driver, BlockDriverState *bs,
  */
 void block_job_sleep_ns(BlockJob *job, QEMUClockType type, int64_t ns);
 
+/**
+ * block_job_yield:
+ * @job: The job that calls the function.
+ *
+ * Yield the block job coroutine.
+ */
+void block_job_yield(BlockJob *job);
+
 /**
  * block_job_completed:
  * @job: The job being completed.