[Qemu-devel] [PATCH 09/10] migration: implement bdrv_all_find_vmstate_bs helper

2015-11-07 Thread Denis V. Lunev 
The patch also ensures proper locking for the operation.

Signed-off-by: Denis V. Lunev 
CC: Juan Quintela 
CC: Stefan Hajnoczi 
CC: Kevin Wolf 
---
 block/snapshot.c | 15 +++
 include/block/snapshot.h |  2 ++
 migration/savevm.c   | 19 ---
 3 files changed, 21 insertions(+), 15 deletions(-)

diff --git a/block/snapshot.c b/block/snapshot.c
index 4daf9d4..337ac8e 100644
--- a/block/snapshot.c
+++ b/block/snapshot.c
@@ -465,3 +465,18 @@ int bdrv_all_create_snapshot(QEMUSnapshotInfo *sn, 
BlockDriverState **bad)
 *bad = bs;
 return err;
 }
+
+BlockDriverState *bdrv_all_find_vmstate_bs(void)
+{
+bool not_found = true;
+BlockDriverState *bs = NULL;
+
+while (not_found && (bs = bdrv_next(bs))) {
+AioContext *ctx = bdrv_get_aio_context(bs);
+
+aio_context_acquire(ctx);
+not_found = !bdrv_can_snapshot(bs);
+aio_context_release(ctx);
+}
+return bs;
+}
diff --git a/include/block/snapshot.h b/include/block/snapshot.h
index df443b2..543cbb3 100644
--- a/include/block/snapshot.h
+++ b/include/block/snapshot.h
@@ -88,4 +88,6 @@ int bdrv_all_goto_snapshot(const char *name, BlockDriverState 
**first_bsd_bs);
 int bdrv_all_find_snapshot(const char *name, BlockDriverState **first_bad_bs);
 int bdrv_all_create_snapshot(QEMUSnapshotInfo *sn, BlockDriverState **bad);
 
+BlockDriverState *bdrv_all_find_vmstate_bs(void);
+
 #endif
diff --git a/migration/savevm.c b/migration/savevm.c
index b4a3930..6be30cb 100644
--- a/migration/savevm.c
+++ b/migration/savevm.c
@@ -1237,17 +1237,6 @@ out:
 return ret;
 }
 
-static BlockDriverState *find_vmstate_bs(void)
-{
-BlockDriverState *bs = NULL;
-while ((bs = bdrv_next(bs))) {
-if (bdrv_can_snapshot(bs)) {
-return bs;
-}
-}
-return NULL;
-}
-
 void hmp_savevm(Monitor *mon, const QDict *qdict)
 {
 BlockDriverState *bs, *bs1;
@@ -1275,8 +1264,8 @@ void hmp_savevm(Monitor *mon, const QDict *qdict)
 return;
 }
 
-bs = find_vmstate_bs();
-if (!bs) {
+bs = bdrv_all_find_vmstate_bs();
+if (bs == NULL) {
 monitor_printf(mon, "No block device can accept snapshots\n");
 return;
 }
@@ -1385,7 +1374,7 @@ int load_vmstate(const char *name)
 return ret;
 }
 
-bs_vm_state = find_vmstate_bs();
+bs_vm_state = bdrv_all_find_vmstate_bs();
 if (!bs_vm_state) {
 error_report("No block device supports snapshots");
 return -ENOTSUP;
@@ -1454,7 +1443,7 @@ void hmp_info_snapshots(Monitor *mon, const QDict *qdict)
 int total;
 int *available_snapshots;
 
-bs = find_vmstate_bs();
+bs = bdrv_all_find_vmstate_bs();
 if (!bs) {
 monitor_printf(mon, "No available block device supports snapshots\n");
 return;
-- 
2.5.0

[Qemu-devel] [PATCH 09/10] migration: implement bdrv_all_find_vmstate_bs helper

2015-11-10 Thread Denis V. Lunev 
The patch also ensures proper locking for the operation.

Signed-off-by: Denis V. Lunev 
CC: Juan Quintela 
CC: Stefan Hajnoczi 
CC: Kevin Wolf 
---
 block/snapshot.c | 15 +++
 include/block/snapshot.h |  2 ++
 migration/savevm.c   | 19 ---
 3 files changed, 21 insertions(+), 15 deletions(-)

diff --git a/block/snapshot.c b/block/snapshot.c
index 6de53cb..addb7c9 100644
--- a/block/snapshot.c
+++ b/block/snapshot.c
@@ -470,3 +470,18 @@ int bdrv_all_create_snapshot(QEMUSnapshotInfo *sn,
 *first_bad_bs = bs;
 return err;
 }
+
+BlockDriverState *bdrv_all_find_vmstate_bs(void)
+{
+bool not_found = true;
+BlockDriverState *bs = NULL;
+
+while (not_found && (bs = bdrv_next(bs))) {
+AioContext *ctx = bdrv_get_aio_context(bs);
+
+aio_context_acquire(ctx);
+not_found = !bdrv_can_snapshot(bs);
+aio_context_release(ctx);
+}
+return bs;
+}
diff --git a/include/block/snapshot.h b/include/block/snapshot.h
index 5f43c0b..a42a694 100644
--- a/include/block/snapshot.h
+++ b/include/block/snapshot.h
@@ -92,4 +92,6 @@ int bdrv_all_create_snapshot(QEMUSnapshotInfo *sn,
  uint64_t vm_state_size,
  BlockDriverState **first_bad_bs);
 
+BlockDriverState *bdrv_all_find_vmstate_bs(void);
+
 #endif
diff --git a/migration/savevm.c b/migration/savevm.c
index f4da064..20c95b2 100644
--- a/migration/savevm.c
+++ b/migration/savevm.c
@@ -1237,17 +1237,6 @@ out:
 return ret;
 }
 
-static BlockDriverState *find_vmstate_bs(void)
-{
-BlockDriverState *bs = NULL;
-while ((bs = bdrv_next(bs))) {
-if (bdrv_can_snapshot(bs)) {
-return bs;
-}
-}
-return NULL;
-}
-
 void hmp_savevm(Monitor *mon, const QDict *qdict)
 {
 BlockDriverState *bs, *bs1;
@@ -1276,8 +1265,8 @@ void hmp_savevm(Monitor *mon, const QDict *qdict)
 return;
 }
 
-bs = find_vmstate_bs();
-if (!bs) {
+bs = bdrv_all_find_vmstate_bs();
+if (bs == NULL) {
 monitor_printf(mon, "No block device can accept snapshots\n");
 return;
 }
@@ -1386,7 +1375,7 @@ int load_vmstate(const char *name)
 return ret;
 }
 
-bs_vm_state = find_vmstate_bs();
+bs_vm_state = bdrv_all_find_vmstate_bs();
 if (!bs_vm_state) {
 error_report("No block device supports snapshots");
 return -ENOTSUP;
@@ -1455,7 +1444,7 @@ void hmp_info_snapshots(Monitor *mon, const QDict *qdict)
 int total;
 int *available_snapshots;
 
-bs = find_vmstate_bs();
+bs = bdrv_all_find_vmstate_bs();
 if (!bs) {
 monitor_printf(mon, "No available block device supports snapshots\n");
 return;
-- 
2.5.0

[Qemu-devel] [PATCH 09/10] migration: implement bdrv_all_find_vmstate_bs helper

2015-11-16 Thread Denis V. Lunev 
The patch also ensures proper locking for the operation.

Signed-off-by: Denis V. Lunev 
Reviewed-by: Fam Zheng 
Reviewed-by: Stefan Hajnoczi 
CC: Juan Quintela 
CC: Kevin Wolf 
---
 block/snapshot.c | 15 +++
 include/block/snapshot.h |  2 ++
 migration/savevm.c   | 19 ---
 3 files changed, 21 insertions(+), 15 deletions(-)

diff --git a/block/snapshot.c b/block/snapshot.c
index 1852328..6ccb1c9 100644
--- a/block/snapshot.c
+++ b/block/snapshot.c
@@ -475,3 +475,18 @@ int bdrv_all_create_snapshot(QEMUSnapshotInfo *sn,
 *first_bad_bs = bs;
 return err;
 }
+
+BlockDriverState *bdrv_all_find_vmstate_bs(void)
+{
+bool not_found = true;
+BlockDriverState *bs = NULL;
+
+while (not_found && (bs = bdrv_next(bs))) {
+AioContext *ctx = bdrv_get_aio_context(bs);
+
+aio_context_acquire(ctx);
+not_found = !bdrv_can_snapshot(bs);
+aio_context_release(ctx);
+}
+return bs;
+}
diff --git a/include/block/snapshot.h b/include/block/snapshot.h
index f4f6409..c925105 100644
--- a/include/block/snapshot.h
+++ b/include/block/snapshot.h
@@ -92,4 +92,6 @@ int bdrv_all_create_snapshot(QEMUSnapshotInfo *sn,
  uint64_t vm_state_size,
  BlockDriverState **first_bad_bs);
 
+BlockDriverState *bdrv_all_find_vmstate_bs(void);
+
 #endif
diff --git a/migration/savevm.c b/migration/savevm.c
index 9ec9117..953b559 100644
--- a/migration/savevm.c
+++ b/migration/savevm.c
@@ -1905,17 +1905,6 @@ int qemu_loadvm_state(QEMUFile *f)
 return ret;
 }
 
-static BlockDriverState *find_vmstate_bs(void)
-{
-BlockDriverState *bs = NULL;
-while ((bs = bdrv_next(bs))) {
-if (bdrv_can_snapshot(bs)) {
-return bs;
-}
-}
-return NULL;
-}
-
 void hmp_savevm(Monitor *mon, const QDict *qdict)
 {
 BlockDriverState *bs, *bs1;
@@ -1944,8 +1933,8 @@ void hmp_savevm(Monitor *mon, const QDict *qdict)
 return;
 }
 
-bs = find_vmstate_bs();
-if (!bs) {
+bs = bdrv_all_find_vmstate_bs();
+if (bs == NULL) {
 monitor_printf(mon, "No block device can accept snapshots\n");
 return;
 }
@@ -2054,7 +2043,7 @@ int load_vmstate(const char *name)
 return ret;
 }
 
-bs_vm_state = find_vmstate_bs();
+bs_vm_state = bdrv_all_find_vmstate_bs();
 if (!bs_vm_state) {
 error_report("No block device supports snapshots");
 return -ENOTSUP;
@@ -2123,7 +2112,7 @@ void hmp_info_snapshots(Monitor *mon, const QDict *qdict)
 int total;
 int *available_snapshots;
 
-bs = find_vmstate_bs();
+bs = bdrv_all_find_vmstate_bs();
 if (!bs) {
 monitor_printf(mon, "No available block device supports snapshots\n");
 return;
-- 
2.5.0