[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]
[Qemu-devel] [PATCH v6 11/12] qed: Implement .bdrv_drain
From: |
Fam Zheng |
Subject: |
[Qemu-devel] [PATCH v6 11/12] qed: Implement .bdrv_drain |
Date: |
Thu, 22 Oct 2015 14:32:59 +0800 |
The "need_check_timer" is used to clear the "NEED_CHECK" flag in the
image header after a grace period once metadata update has finished. In
compliance to the bdrv_drain semantics we should make sure it remains
deleted once .bdrv_drain is called.
We cannot reuse qed_need_check_timer_cb because it calls bdrv_aio_flush
with a completion callback that starts more I/O, bdrv_drain cannot cope
with this. Also the assertions in qed_need_check_timer_cb and
qed_unplug_allocating_write_reqs are not guaranteed in the case of
bdrv_qed_drain.
Signed-off-by: Fam Zheng <address@hidden>
---
block/qed.c | 15 +++++++++++++++
1 file changed, 15 insertions(+)
diff --git a/block/qed.c b/block/qed.c
index 5ea05d4..d63a7de 100644
--- a/block/qed.c
+++ b/block/qed.c
@@ -375,6 +375,20 @@ static void bdrv_qed_attach_aio_context(BlockDriverState
*bs,
}
}
+static void bdrv_qed_drain(BlockDriverState *bs)
+{
+ BDRVQEDState *s = bs->opaque;
+ int ret;
+
+ /* Cancel timer and start doing I/O that were meant to happen when it
+ * fires, that way we get bdrv_drain() taking care of the requests
+ * correctly. */
+ qed_cancel_need_check_timer(s);
+ qed_plug_allocating_write_reqs(s);
+ ret = bdrv_flush(s->bs);
+ qed_clear_need_check(s, ret);
+}
+
static int bdrv_qed_open(BlockDriverState *bs, QDict *options, int flags,
Error **errp)
{
@@ -1676,6 +1690,7 @@ static BlockDriver bdrv_qed = {
.bdrv_check = bdrv_qed_check,
.bdrv_detach_aio_context = bdrv_qed_detach_aio_context,
.bdrv_attach_aio_context = bdrv_qed_attach_aio_context,
+ .bdrv_drain = bdrv_qed_drain,
};
static void bdrv_qed_init(void)
--
2.4.3
- [Qemu-devel] [PATCH v6 03/12] dataplane: Mark host notifiers' client type as "external", (continued)
- [Qemu-devel] [PATCH v6 03/12] dataplane: Mark host notifiers' client type as "external", Fam Zheng, 2015/10/22
- [Qemu-devel] [PATCH v6 04/12] aio: introduce aio_{disable, enable}_external, Fam Zheng, 2015/10/22
- [Qemu-devel] [PATCH v6 05/12] block: Introduce "drained begin/end" API, Fam Zheng, 2015/10/22
- [Qemu-devel] [PATCH v6 06/12] block: Add "drained begin/end" for transactional external snapshot, Fam Zheng, 2015/10/22
- [Qemu-devel] [PATCH v6 07/12] block: Add "drained begin/end" for transactional backup, Fam Zheng, 2015/10/22
- [Qemu-devel] [PATCH v6 08/12] block: Add "drained begin/end" for transactional blockdev-backup, Fam Zheng, 2015/10/22
- [Qemu-devel] [PATCH v6 09/12] block: Add "drained begin/end" for internal snapshot, Fam Zheng, 2015/10/22
- [Qemu-devel] [PATCH v6 10/12] block: Introduce BlockDriver.bdrv_drain callback, Fam Zheng, 2015/10/22
- [Qemu-devel] [PATCH v6 11/12] qed: Implement .bdrv_drain,
Fam Zheng <=
- [Qemu-devel] [PATCH v6 12/12] tests: Add test case for aio_disable_external, Fam Zheng, 2015/10/22