|
 |
0a122b |
From 6c473bbd42becf52b10677500bb509fbfa077140 Mon Sep 17 00:00:00 2001
|
|
|
0a122b |
From: Fam Zheng <famz@redhat.com>
|
|
|
0a122b |
Date: Fri, 17 Jan 2014 03:07:47 +0100
|
|
|
0a122b |
Subject: [PATCH 04/34] block: implement reference count for BlockDriverState
|
|
|
0a122b |
|
|
|
0a122b |
RH-Author: Fam Zheng <famz@redhat.com>
|
|
|
0a122b |
Message-id: <1389928083-8921-3-git-send-email-famz@redhat.com>
|
|
|
0a122b |
Patchwork-id: 56764
|
|
|
0a122b |
O-Subject: [RHEL-7 qemu-kvm PATCH 02/18] block: implement reference count for BlockDriverState
|
|
|
0a122b |
Bugzilla: 1041301
|
|
|
0a122b |
RH-Acked-by: Jeffrey Cody <jcody@redhat.com>
|
|
|
0a122b |
RH-Acked-by: Kevin Wolf <kwolf@redhat.com>
|
|
|
0a122b |
RH-Acked-by: Stefan Hajnoczi <stefanha@redhat.com>
|
|
|
0a122b |
|
|
|
0a122b |
Introduce bdrv_ref/bdrv_unref to manage the lifecycle of
|
|
|
0a122b |
BlockDriverState. They are unused for now but will used to replace
|
|
|
0a122b |
bdrv_delete() later.
|
|
|
0a122b |
|
|
|
0a122b |
Signed-off-by: Fam Zheng <famz@redhat.com>
|
|
|
0a122b |
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
|
|
|
0a122b |
(cherry picked from commit 9fcb025146676ab376e6159b58f5a5ddb67bf03c)
|
|
|
0a122b |
Signed-off-by: Fam Zheng <famz@redhat.com>
|
|
|
0a122b |
|
|
|
0a122b |
Conflicts:
|
|
|
0a122b |
block.c
|
|
|
0a122b |
Context conflict because throttling and before_write notifier
|
|
|
0a122b |
are not backported yet.
|
|
|
0a122b |
|
|
|
0a122b |
Signed-off-by: Fam Zheng <famz@redhat.com>
|
|
|
0a122b |
---
|
|
|
0a122b |
block.c | 21 +++++++++++++++++++++
|
|
|
0a122b |
include/block/block.h | 2 ++
|
|
|
0a122b |
include/block/block_int.h | 1 +
|
|
|
0a122b |
3 files changed, 24 insertions(+)
|
|
|
0a122b |
|
|
|
0a122b |
Signed-off-by: Miroslav Rezanina <mrezanin@redhat.com>
|
|
|
0a122b |
---
|
|
|
0a122b |
block.c | 21 +++++++++++++++++++++
|
|
|
0a122b |
include/block/block.h | 2 ++
|
|
|
0a122b |
include/block/block_int.h | 1 +
|
|
|
0a122b |
3 files changed, 24 insertions(+), 0 deletions(-)
|
|
|
0a122b |
|
|
|
0a122b |
diff --git a/block.c b/block.c
|
|
|
0a122b |
index cc7afd4..ddf29d0 100644
|
|
|
0a122b |
--- a/block.c
|
|
|
0a122b |
+++ b/block.c
|
|
|
0a122b |
@@ -301,6 +301,7 @@ BlockDriverState *bdrv_new(const char *device_name)
|
|
|
0a122b |
}
|
|
|
0a122b |
bdrv_iostatus_disable(bs);
|
|
|
0a122b |
notifier_list_init(&bs->close_notifiers);
|
|
|
0a122b |
+ bs->refcnt = 1;
|
|
|
0a122b |
|
|
|
0a122b |
return bs;
|
|
|
0a122b |
}
|
|
|
0a122b |
@@ -1580,6 +1581,9 @@ static void bdrv_move_feature_fields(BlockDriverState *bs_dest,
|
|
|
0a122b |
/* dirty bitmap */
|
|
|
0a122b |
bs_dest->dirty_bitmap = bs_src->dirty_bitmap;
|
|
|
0a122b |
|
|
|
0a122b |
+ /* reference count */
|
|
|
0a122b |
+ bs_dest->refcnt = bs_src->refcnt;
|
|
|
0a122b |
+
|
|
|
0a122b |
/* job */
|
|
|
0a122b |
bs_dest->in_use = bs_src->in_use;
|
|
|
0a122b |
bs_dest->job = bs_src->job;
|
|
|
0a122b |
@@ -4754,6 +4758,23 @@ int64_t bdrv_get_dirty_count(BlockDriverState *bs)
|
|
|
0a122b |
}
|
|
|
0a122b |
}
|
|
|
0a122b |
|
|
|
0a122b |
+/* Get a reference to bs */
|
|
|
0a122b |
+void bdrv_ref(BlockDriverState *bs)
|
|
|
0a122b |
+{
|
|
|
0a122b |
+ bs->refcnt++;
|
|
|
0a122b |
+}
|
|
|
0a122b |
+
|
|
|
0a122b |
+/* Release a previously grabbed reference to bs.
|
|
|
0a122b |
+ * If after releasing, reference count is zero, the BlockDriverState is
|
|
|
0a122b |
+ * deleted. */
|
|
|
0a122b |
+void bdrv_unref(BlockDriverState *bs)
|
|
|
0a122b |
+{
|
|
|
0a122b |
+ assert(bs->refcnt > 0);
|
|
|
0a122b |
+ if (--bs->refcnt == 0) {
|
|
|
0a122b |
+ bdrv_delete(bs);
|
|
|
0a122b |
+ }
|
|
|
0a122b |
+}
|
|
|
0a122b |
+
|
|
|
0a122b |
void bdrv_set_in_use(BlockDriverState *bs, int in_use)
|
|
|
0a122b |
{
|
|
|
0a122b |
assert(bs->in_use != in_use);
|
|
|
0a122b |
diff --git a/include/block/block.h b/include/block/block.h
|
|
|
0a122b |
index e7f718c..a3b7395 100644
|
|
|
0a122b |
--- a/include/block/block.h
|
|
|
0a122b |
+++ b/include/block/block.h
|
|
|
0a122b |
@@ -421,6 +421,8 @@ int64_t bdrv_get_dirty_count(BlockDriverState *bs);
|
|
|
0a122b |
void bdrv_enable_copy_on_read(BlockDriverState *bs);
|
|
|
0a122b |
void bdrv_disable_copy_on_read(BlockDriverState *bs);
|
|
|
0a122b |
|
|
|
0a122b |
+void bdrv_ref(BlockDriverState *bs);
|
|
|
0a122b |
+void bdrv_unref(BlockDriverState *bs);
|
|
|
0a122b |
void bdrv_set_in_use(BlockDriverState *bs, int in_use);
|
|
|
0a122b |
int bdrv_in_use(BlockDriverState *bs);
|
|
|
0a122b |
|
|
|
0a122b |
diff --git a/include/block/block_int.h b/include/block/block_int.h
|
|
|
0a122b |
index d49a317..fbfdab7 100644
|
|
|
0a122b |
--- a/include/block/block_int.h
|
|
|
0a122b |
+++ b/include/block/block_int.h
|
|
|
0a122b |
@@ -315,6 +315,7 @@ struct BlockDriverState {
|
|
|
0a122b |
BlockDeviceIoStatus iostatus;
|
|
|
0a122b |
char device_name[32];
|
|
|
0a122b |
HBitmap *dirty_bitmap;
|
|
|
0a122b |
+ int refcnt;
|
|
|
0a122b |
int in_use; /* users other than guest access, eg. block migration */
|
|
|
0a122b |
QTAILQ_ENTRY(BlockDriverState) list;
|
|
|
0a122b |
|
|
|
0a122b |
--
|
|
|
0a122b |
1.7.1
|
|
|
0a122b |
|