Hyper-V always use 4k page size (HV_HYP_PAGE_SIZE), so when
communicating with Hyper-V, a guest should always use HV_HYP_PAGE_SIZE
as the unit for page related data. For storvsc, the data is
vmbus_packet_mpb_array. And since in scsi_cmnd, sglist of pages (in unit
of PAGE_SIZE) is used, we need convert pages in the sglist of scsi_cmnd
into Hyper-V pages in vmbus_packet_mpb_array.
This patch does the conversion by dividing pages in sglist into Hyper-V
pages, offset and indexes in vmbus_packet_mpb_array are recalculated
accordingly.
Signed-off-by: Boqun Feng <boqun.feng@xxxxxxxxx>
---
drivers/scsi/storvsc_drv.c | 27 +++++++++++++++++++++------
1 file changed, 21 insertions(+), 6 deletions(-)
diff --git a/drivers/scsi/storvsc_drv.c b/drivers/scsi/storvsc_drv.c
index fb41636519ee..c54d25f279bc 100644
--- a/drivers/scsi/storvsc_drv.c
+++ b/drivers/scsi/storvsc_drv.c
@@ -1561,7 +1561,7 @@ static int storvsc_queuecommand(struct Scsi_Host *host, struct scsi_cmnd *scmnd)
struct hv_host_device *host_dev = shost_priv(host);
struct hv_device *dev = host_dev->dev;
struct storvsc_cmd_request *cmd_request = scsi_cmd_priv(scmnd);
- int i;
+ int i, j, k;
struct scatterlist *sgl;
unsigned int sg_count = 0;
struct vmscsi_request *vm_srb;
@@ -1569,6 +1569,8 @@ static int storvsc_queuecommand(struct Scsi_Host *host, struct scsi_cmnd *scmnd)
struct vmbus_packet_mpb_array *payload;
u32 payload_sz;
u32 length;
+ int subpage_idx = 0;
+ unsigned int hvpg_count = 0;
if (vmstor_proto_version <= VMSTOR_PROTO_VERSION_WIN8) {
/*
@@ -1643,23 +1645,36 @@ static int storvsc_queuecommand(struct Scsi_Host *host, struct scsi_cmnd *scmnd)
payload_sz = sizeof(cmd_request->mpb);
if (sg_count) {
- if (sg_count > MAX_PAGE_BUFFER_COUNT) {
+ hvpg_count = sg_count * (PAGE_SIZE / HV_HYP_PAGE_SIZE);
+ if (hvpg_count > MAX_PAGE_BUFFER_COUNT) {
- payload_sz = (sg_count * sizeof(u64) +
+ payload_sz = (hvpg_count * sizeof(u64) +
sizeof(struct vmbus_packet_mpb_array));
payload = kzalloc(payload_sz, GFP_ATOMIC);
if (!payload)
return SCSI_MLQUEUE_DEVICE_BUSY;
}
+ /*
+ * sgl is a list of PAGEs, and payload->range.pfn_array
+ * expects the page number in the unit of HV_HYP_PAGE_SIZE (the
+ * page size that Hyper-V uses, so here we need to divide PAGEs
+ * into HV_HYP_PAGE in case that PAGE_SIZE > HV_HYP_PAGE_SIZE.
+ */
payload->range.len = length;
- payload->range.offset = sgl[0].offset;
+ payload->range.offset = sgl[0].offset & ~HV_HYP_PAGE_MASK;
+ subpage_idx = sgl[0].offset >> HV_HYP_PAGE_SHIFT;
cur_sgl = sgl;
+ k = 0;
for (i = 0; i < sg_count; i++) {
- payload->range.pfn_array[i] =
- page_to_pfn(sg_page((cur_sgl)));
+ for (j = subpage_idx; j < (PAGE_SIZE / HV_HYP_PAGE_SIZE); j++) {
+ payload->range.pfn_array[k] =
+ page_to_hvpfn(sg_page((cur_sgl))) + j;
+ k++;
+ }
cur_sgl = sg_next(cur_sgl);
+ subpage_idx = 0;
}
}
--
2.27.0
