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path: root/drivers/scsi/storvsc_drv.c
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Diffstat (limited to 'drivers/scsi/storvsc_drv.c')
-rw-r--r--drivers/scsi/storvsc_drv.c27
1 files changed, 22 insertions, 5 deletions
diff --git a/drivers/scsi/storvsc_drv.c b/drivers/scsi/storvsc_drv.c
index ca3530982e52..fe000da11332 100644
--- a/drivers/scsi/storvsc_drv.c
+++ b/drivers/scsi/storvsc_drv.c
@@ -1844,7 +1844,7 @@ static struct scsi_host_template scsi_driver = {
.cmd_per_lun = 2048,
.this_id = -1,
/* Ensure there are no gaps in presented sgls */
- .virt_boundary_mask = PAGE_SIZE-1,
+ .virt_boundary_mask = HV_HYP_PAGE_SIZE - 1,
.no_write_same = 1,
.track_queue_depth = 1,
.change_queue_depth = storvsc_change_queue_depth,
@@ -1895,6 +1895,7 @@ static int storvsc_probe(struct hv_device *device,
int target = 0;
struct storvsc_device *stor_device;
int max_sub_channels = 0;
+ u32 max_xfer_bytes;
/*
* We support sub-channels for storage on SCSI and FC controllers.
@@ -1968,12 +1969,28 @@ static int storvsc_probe(struct hv_device *device,
}
/* max cmd length */
host->max_cmd_len = STORVSC_MAX_CMD_LEN;
-
/*
- * set the table size based on the info we got
- * from the host.
+ * Any reasonable Hyper-V configuration should provide
+ * max_transfer_bytes value aligning to HV_HYP_PAGE_SIZE,
+ * protecting it from any weird value.
+ */
+ max_xfer_bytes = round_down(stor_device->max_transfer_bytes, HV_HYP_PAGE_SIZE);
+ /* max_hw_sectors_kb */
+ host->max_sectors = max_xfer_bytes >> 9;
+ /*
+ * There are 2 requirements for Hyper-V storvsc sgl segments,
+ * based on which the below calculation for max segments is
+ * done:
+ *
+ * 1. Except for the first and last sgl segment, all sgl segments
+ * should be align to HV_HYP_PAGE_SIZE, that also means the
+ * maximum number of segments in a sgl can be calculated by
+ * dividing the total max transfer length by HV_HYP_PAGE_SIZE.
+ *
+ * 2. Except for the first and last, each entry in the SGL must
+ * have an offset that is a multiple of HV_HYP_PAGE_SIZE.
*/
- host->sg_tablesize = (stor_device->max_transfer_bytes >> PAGE_SHIFT);
+ host->sg_tablesize = (max_xfer_bytes >> HV_HYP_PAGE_SHIFT) + 1;
/*
* For non-IDE disks, the host supports multiple channels.
* Set the number of HW queues we are supporting.