scsi: storvsc: Fix unsigned comparison to zero

The unsigned variable sg_count is being assigned a return value
from the call to scsi_dma_map() that can return -ENOMEM.

Signed-off-by: YueHaibing <yuehaibing@huawei.com>
Reviewed-by: Michael Kelley <mikelley@microsoft.com>
Link: https://lore.kernel.org/r/20211227040311.54584-1-yuehaibing@huawei.com
Signed-off-by: Wei Liu <wei.liu@kernel.org>

diff --git a/drivers/scsi/storvsc_drv.c b/drivers/scsi/storvsc_drv.c
index ae29360..2273b84 100644 (file)
--- a/drivers/scsi/storvsc_drv.c
+++ b/drivers/scsi/storvsc_drv.c
@@ -1753,7 +1753,6 @@ static int storvsc_queuecommand(struct Scsi_Host *host, struct scsi_cmnd *scmnd)
        struct hv_device *dev = host_dev->dev;
        struct storvsc_cmd_request *cmd_request = scsi_cmd_priv(scmnd);
        struct scatterlist *sgl;
-       unsigned int sg_count;
        struct vmscsi_request *vm_srb;
        struct vmbus_packet_mpb_array  *payload;
        u32 payload_sz;
@@ -1826,18 +1825,17 @@ static int storvsc_queuecommand(struct Scsi_Host *host, struct scsi_cmnd *scmnd)
        memcpy(vm_srb->cdb, scmnd->cmnd, vm_srb->cdb_length);
 
        sgl = (struct scatterlist *)scsi_sglist(scmnd);
-       sg_count = scsi_sg_count(scmnd);
 
        length = scsi_bufflen(scmnd);
        payload = (struct vmbus_packet_mpb_array *)&cmd_request->mpb;
        payload_sz = sizeof(cmd_request->mpb);
 
-       if (sg_count) {
+       if (scsi_sg_count(scmnd)) {
                unsigned long offset_in_hvpg = offset_in_hvpage(sgl->offset);
                unsigned int hvpg_count = HVPFN_UP(offset_in_hvpg + length);
                struct scatterlist *sg;
                unsigned long hvpfn, hvpfns_to_add;
-               int j, i = 0;
+               int j, i = 0, sg_count;
 
                if (hvpg_count > MAX_PAGE_BUFFER_COUNT) {