[Sheepdog] [RFC PATCH 1/2] close all the block drivers before the qemu process exits

[MORITA Kazutaka]

This patch calls the close handler of the block driver before the qemu
process exits.

This is necessary because the sheepdog block driver releases the lock
of VM images in the close handler.

Signed-off-by: MORITA Kazutaka <morita.kazutaka at lab.ntt.co.jp>
---
 block.c   |   11 +++++++++++
 block.h   |    1 +
 monitor.c |    1 +
 vl.c      |    1 +
 4 files changed, 14 insertions(+), 0 deletions(-)

diff --git a/block.c b/block.c
index 7326bfe..a606820 100644
--- a/block.c
+++ b/block.c
@@ -526,6 +526,17 @@ void bdrv_close(BlockDriverState *bs)
     }
 }
 
+void bdrv_close_all(void)
+{
+    BlockDriverState *bs, *n;
+
+    for (bs = bdrv_first, n = bs->next; bs; bs = n, n = bs ? bs->next : NULL) {
+        if (bs && bs->drv && bs->drv->bdrv_close) {
+            bs->drv->bdrv_close(bs);
+        }
+    }
+}
+
 void bdrv_delete(BlockDriverState *bs)
 {
     BlockDriverState **pbs;
diff --git a/block.h b/block.h
index fa51ddf..1a1293a 100644
--- a/block.h
+++ b/block.h
@@ -123,6 +123,7 @@ BlockDriverAIOCB *bdrv_aio_ioctl(BlockDriverState *bs,
 /* Ensure contents are flushed to disk.  */
 void bdrv_flush(BlockDriverState *bs);
 void bdrv_flush_all(void);
+void bdrv_close_all(void);
 
 int bdrv_is_allocated(BlockDriverState *bs, int64_t sector_num, int nb_sectors,
 	int *pnum);
diff --git a/monitor.c b/monitor.c
index 17e59f5..44bfe83 100644
--- a/monitor.c
+++ b/monitor.c
@@ -845,6 +845,7 @@ static void do_info_cpu_stats(Monitor *mon)
  */
 static void do_quit(Monitor *mon, const QDict *qdict, QObject **ret_data)
 {
+    bdrv_close_all();
     exit(0);
 }
 
diff --git a/vl.c b/vl.c
index 77677e8..65160ed 100644
--- a/vl.c
+++ b/vl.c
@@ -4205,6 +4205,7 @@ static void main_loop(void)
             vm_stop(r);
         }
     }
+    bdrv_close_all();
     pause_all_vcpus();
 }
 
-- 
1.5.6.5