Staging: hv: storvsc: Optimize the bounce buffer handling in the "read" case

Optimize the bounce buffer handling in the "read" case.

Signed-off-by: K. Y. Srinivasan <kys@microsoft.com>
Signed-off-by: Haiyang Zhang <haiyangz@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

diff --git a/drivers/staging/hv/storvsc_drv.c b/drivers/staging/hv/storvsc_drv.c
index 90b91ad..3e00e70 100644 (file)
--- a/drivers/staging/hv/storvsc_drv.c
+++ b/drivers/staging/hv/storvsc_drv.c
@@ -560,12 +560,10 @@ static int storvsc_queuecommand_lck(struct scsi_cmnd *scmnd,
                                ALIGN(scsi_bufflen(scmnd), PAGE_SIZE) >>
                                        PAGE_SHIFT;
 
-                       /*
-                        * FIXME: We can optimize on reads by just skipping
-                        * this
-                        */
-                       copy_to_bounce_buffer(sgl, cmd_request->bounce_sgl,
-                                             scsi_sg_count(scmnd));
+                       if (vm_srb->data_in == WRITE_TYPE)
+                               copy_to_bounce_buffer(sgl,
+                                       cmd_request->bounce_sgl,
+                                       scsi_sg_count(scmnd));
 
                        sgl = cmd_request->bounce_sgl;
                        sg_count = cmd_request->bounce_sgl_count;