Expose VIRTIO_BLK_F_DISCARD and VIRTIO_BLK_F_WRITE_ZEROES features
to the drivers and handle VIRTIO_BLK_T_DISCARD and
VIRTIO_BLK_T_WRITE_ZEROES requests checking ranges and flags.
The simulator behaves like a ramdisk, so for VIRTIO_BLK_F_DISCARD
does nothing, while for VIRTIO_BLK_T_WRITE_ZEROES sets to 0 the
specified region.
Signed-off-by: Stefano Garzarella <sgarzare@xxxxxxxxxx>
---
drivers/vdpa/vdpa_sim/vdpa_sim_blk.c | 74 +++++++++++++++++++++++++++-
1 file changed, 73 insertions(+), 1 deletion(-)
diff --git a/drivers/vdpa/vdpa_sim/vdpa_sim_blk.c b/drivers/vdpa/vdpa_sim/vdpa_sim_blk.c
index 1f18f336cf0c..db85df1d5073 100644
--- a/drivers/vdpa/vdpa_sim/vdpa_sim_blk.c
+++ b/drivers/vdpa/vdpa_sim/vdpa_sim_blk.c
@@ -30,11 +30,14 @@
(1ULL << VIRTIO_BLK_F_SEG_MAX) | \
(1ULL << VIRTIO_BLK_F_BLK_SIZE) | \
(1ULL << VIRTIO_BLK_F_TOPOLOGY) | \
- (1ULL << VIRTIO_BLK_F_MQ))
+ (1ULL << VIRTIO_BLK_F_MQ) | \
+ (1ULL << VIRTIO_BLK_F_DISCARD) | \
+ (1ULL << VIRTIO_BLK_F_WRITE_ZEROES))
#define VDPASIM_BLK_CAPACITY 0x40000
#define VDPASIM_BLK_SIZE_MAX 0x1000
#define VDPASIM_BLK_SEG_MAX 32
+#define VDPASIM_BLK_DWZ_MAX_SECTORS UINT_MAX
/* 1 virtqueue, 1 address space, 1 virtqueue group */
#define VDPASIM_BLK_VQ_NUM 1
@@ -193,6 +196,64 @@ static bool vdpasim_blk_handle_req(struct vdpasim *vdpasim,
/* nothing to do */
break;
+ case VIRTIO_BLK_T_DISCARD:
+ case VIRTIO_BLK_T_WRITE_ZEROES:
+ struct virtio_blk_discard_write_zeroes range;
+ u32 num_sectors, flags;
+
+ if (to_pull != sizeof(range)) {
+ dev_dbg(&vdpasim->vdpa.dev,
+ "discard/write_zeroes header len: 0x%zx [expected: 0x%zx]\n",
+ to_pull, sizeof(range));
+ status = VIRTIO_BLK_S_IOERR;
+ break;
+ }
+
+ bytes = vringh_iov_pull_iotlb(&vq->vring, &vq->out_iov, &range,
+ to_pull);
+ if (bytes < 0) {
+ dev_dbg(&vdpasim->vdpa.dev,
+ "vringh_iov_pull_iotlb() error: %zd offset: 0x%llx len: 0x%zx\n",
+ bytes, offset, to_pull);
+ status = VIRTIO_BLK_S_IOERR;
+ break;
+ }
+
+ sector = vdpasim64_to_cpu(vdpasim, range.sector);
+ offset = sector << SECTOR_SHIFT;
+ num_sectors = vdpasim32_to_cpu(vdpasim, range.num_sectors);
+ flags = vdpasim32_to_cpu(vdpasim, range.flags);
+
+ if (type == VIRTIO_BLK_T_DISCARD && flags != 0) {
+ dev_dbg(&vdpasim->vdpa.dev,
+ "discard unexpected flags set - flags: 0x%x\n",
+ flags);
+ status = VIRTIO_BLK_S_UNSUPP;
+ break;
+ }
+
+ if (type == VIRTIO_BLK_T_WRITE_ZEROES &&
+ flags & ~VIRTIO_BLK_WRITE_ZEROES_FLAG_UNMAP) {
+ dev_dbg(&vdpasim->vdpa.dev,
+ "write_zeroes unexpected flags set - flags: 0x%x\n",
+ flags);
+ status = VIRTIO_BLK_S_UNSUPP;
+ break;
+ }
+
+ if (!vdpasim_blk_check_range(vdpasim, sector, num_sectors,
+ VDPASIM_BLK_DWZ_MAX_SECTORS)) {
+ status = VIRTIO_BLK_S_IOERR;
+ break;
+ }
+
+ if (type == VIRTIO_BLK_T_WRITE_ZEROES) {
+ memset(vdpasim->buffer + offset, 0,
+ num_sectors << SECTOR_SHIFT);
+ }
+
+ break;
+
default:
dev_dbg(&vdpasim->vdpa.dev,
"Unsupported request type %d\n", type);
@@ -281,6 +342,17 @@ static void vdpasim_blk_get_config(struct vdpasim *vdpasim, void *config)
blk_config->min_io_size = cpu_to_vdpasim16(vdpasim, 1);
blk_config->opt_io_size = cpu_to_vdpasim32(vdpasim, 1);
blk_config->blk_size = cpu_to_vdpasim32(vdpasim, SECTOR_SIZE);
+ /* VIRTIO_BLK_F_DISCARD */
+ blk_config->discard_sector_alignment =
+ cpu_to_vdpasim32(vdpasim, SECTOR_SIZE);
+ blk_config->max_discard_sectors =
+ cpu_to_vdpasim32(vdpasim, VDPASIM_BLK_DWZ_MAX_SECTORS);
+ blk_config->max_discard_seg = cpu_to_vdpasim32(vdpasim, 1);
+ /* VIRTIO_BLK_F_WRITE_ZEROES */
+ blk_config->max_write_zeroes_sectors =
+ cpu_to_vdpasim32(vdpasim, VDPASIM_BLK_DWZ_MAX_SECTORS);
+ blk_config->max_write_zeroes_seg = cpu_to_vdpasim32(vdpasim, 1);
+
}
static void vdpasim_blk_mgmtdev_release(struct device *dev)
--
2.37.1
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