[Top][All Lists]
[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]
[Qemu-devel] [PATCH 1/2] virtio-blk: support VIRTIO_BLK_F_CONFIG_WCE
From: |
Paolo Bonzini |
Subject: |
[Qemu-devel] [PATCH 1/2] virtio-blk: support VIRTIO_BLK_F_CONFIG_WCE |
Date: |
Tue, 3 Jul 2012 15:20:41 +0200 |
Introduce a new feature bit and configuration field that provide
support for toggling the cache mode between writethrough and writeback.
Also rename VIRTIO_BLK_F_WCACHE to VIRTIO_BLK_F_WCE for consistency with
the spec.
Signed-off-by: Paolo Bonzini <address@hidden>
---
hw/virtio-blk.c | 16 ++++++++++++++--
hw/virtio-blk.h | 4 +++-
2 files changed, 17 insertions(+), 3 deletions(-)
diff --git a/hw/virtio-blk.c b/hw/virtio-blk.c
index fe07746..280f96d 100644
--- a/hw/virtio-blk.c
+++ b/hw/virtio-blk.c
@@ -510,9 +510,19 @@ static void virtio_blk_update_config(VirtIODevice *vdev,
uint8_t *config)
blkcfg.size_max = 0;
blkcfg.physical_block_exp = get_physical_block_exp(s->conf);
blkcfg.alignment_offset = 0;
+ blkcfg.wce = bdrv_enable_write_cache(s->bs);
memcpy(config, &blkcfg, sizeof(struct virtio_blk_config));
}
+static void virtio_blk_set_config(VirtIODevice *vdev, const uint8_t *config)
+{
+ VirtIOBlock *s = to_virtio_blk(vdev);
+ struct virtio_blk_config blkcfg;
+
+ memcpy(&blkcfg, config, sizeof(blkcfg));
+ bdrv_set_enable_write_cache(s->bs, blkcfg.wce != 0);
+}
+
static uint32_t virtio_blk_get_features(VirtIODevice *vdev, uint32_t features)
{
VirtIOBlock *s = to_virtio_blk(vdev);
@@ -523,9 +533,10 @@ static uint32_t virtio_blk_get_features(VirtIODevice
*vdev, uint32_t features)
features |= (1 << VIRTIO_BLK_F_BLK_SIZE);
features |= (1 << VIRTIO_BLK_F_SCSI);
+ features |= (1 << VIRTIO_BLK_F_CONFIG_WCE);
if (bdrv_enable_write_cache(s->bs))
- features |= (1 << VIRTIO_BLK_F_WCACHE);
-
+ features |= (1 << VIRTIO_BLK_F_WCE);
+
if (bdrv_is_read_only(s->bs))
features |= 1 << VIRTIO_BLK_F_RO;
@@ -615,6 +626,7 @@ VirtIODevice *virtio_blk_init(DeviceState *dev,
VirtIOBlkConf *blk)
sizeof(VirtIOBlock));
s->vdev.get_config = virtio_blk_update_config;
+ s->vdev.set_config = virtio_blk_set_config;
s->vdev.get_features = virtio_blk_get_features;
s->vdev.reset = virtio_blk_reset;
s->bs = blk->conf.bs;
diff --git a/hw/virtio-blk.h b/hw/virtio-blk.h
index d785001..afea114 100644
--- a/hw/virtio-blk.h
+++ b/hw/virtio-blk.h
@@ -31,8 +31,9 @@
#define VIRTIO_BLK_F_BLK_SIZE 6 /* Block size of disk is available*/
#define VIRTIO_BLK_F_SCSI 7 /* Supports scsi command passthru */
/* #define VIRTIO_BLK_F_IDENTIFY 8 ATA IDENTIFY supported, DEPRECATED
*/
-#define VIRTIO_BLK_F_WCACHE 9 /* write cache enabled */
+#define VIRTIO_BLK_F_WCE 9 /* write cache enabled */
#define VIRTIO_BLK_F_TOPOLOGY 10 /* Topology information is available */
+#define VIRTIO_BLK_F_CONFIG_WCE 11 /* write cache configurable */
#define VIRTIO_BLK_ID_BYTES 20 /* ID string length */
@@ -49,6 +50,7 @@ struct virtio_blk_config
uint8_t alignment_offset;
uint16_t min_io_size;
uint32_t opt_io_size;
+ uint8_t wce;
} QEMU_PACKED;
/* These two define direction. */
--
1.7.10.2
- [Qemu-devel] [QEMU PATCH 0/2] virtio-blk: writeback cache enable improvements, Paolo Bonzini, 2012/07/03
- [Qemu-devel] [PATCH 1/2] virtio-blk: support VIRTIO_BLK_F_CONFIG_WCE,
Paolo Bonzini <=
- [Qemu-devel] [PATCH 2/2] virtio-blk: disable write cache if not negotiated, Paolo Bonzini, 2012/07/03
- Re: [Qemu-devel] [PATCH 2/2] virtio-blk: disable write cache if not negotiated, Kevin Wolf, 2012/07/03
- Re: [Qemu-devel] [PATCH 2/2] virtio-blk: disable write cache if not negotiated, Paolo Bonzini, 2012/07/03
- Re: [Qemu-devel] [PATCH 2/2] virtio-blk: disable write cache if not negotiated, Kevin Wolf, 2012/07/04
- Re: [Qemu-devel] [PATCH 2/2] virtio-blk: disable write cache if not negotiated, Paolo Bonzini, 2012/07/04
- Re: [Qemu-devel] [PATCH 2/2] virtio-blk: disable write cache if not negotiated, Kevin Wolf, 2012/07/04
- Re: [Qemu-devel] [PATCH 2/2] virtio-blk: disable write cache if not negotiated, Paolo Bonzini, 2012/07/04
Re: [Qemu-devel] [QEMU PATCH 0/2] virtio-blk: writeback cache enable improvements, Paolo Bonzini, 2012/07/23