[PATCH v3 10/18] hw/block/nvme: flush write cache when disabled

From: Klaus Jensen <its@irrelevant.dk>
To: qemu-block@nongnu.org
Cc: "Kevin Wolf" <kwolf@redhat.com>,
	"Dmitry Fomichev" <dmitry.fomichev@wdc.com>,
	"Klaus Jensen" <k.jensen@samsung.com>,
	qemu-devel@nongnu.org, "Max Reitz" <mreitz@redhat.com>,
	"Klaus Jensen" <its@irrelevant.dk>,
	"Keith Busch" <kbusch@kernel.org>,
	"Javier Gonzalez" <javier.gonz@samsung.com>,
	"Maxim Levitsky" <mlevitsk@redhat.com>,
	"Philippe Mathieu-Daudé" <philmd@redhat.com>
Subject: [PATCH v3 10/18] hw/block/nvme: flush write cache when disabled
Date: Mon,  6 Jul 2020 08:12:55 +0200	[thread overview]
Message-ID: <20200706061303.246057-11-its@irrelevant.dk> (raw)
In-Reply-To: <20200706061303.246057-1-its@irrelevant.dk>

From: Klaus Jensen <k.jensen@samsung.com>

If the write cache is disabled with a Set Features command, flush it if
currently enabled.

Signed-off-by: Klaus Jensen <k.jensen@samsung.com>
Reviewed-by: Dmitry Fomichev <dmitry.fomichev@wdc.com>
---
 hw/block/nvme.c | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/hw/block/nvme.c b/hw/block/nvme.c
index 80c7285bc1cf..8fce2ebf69e7 100644
--- a/hw/block/nvme.c
+++ b/hw/block/nvme.c
@@ -1166,6 +1166,10 @@ static uint16_t nvme_set_feature(NvmeCtrl *n, NvmeCmd *cmd, NvmeRequest *req)
 
         break;
     case NVME_VOLATILE_WRITE_CACHE:
+        if (!(dw11 & 0x1) && blk_enable_write_cache(n->conf.blk)) {
+            blk_flush(n->conf.blk);
+        }
+
         blk_set_enable_write_cache(n->conf.blk, dw11 & 1);
         break;
     case NVME_NUMBER_OF_QUEUES:
-- 
2.27.0


