I wonder if we want to disable write same too, instead of falling back to SD_MAX_WS10_BLOCKS for either of the WRITE SAME (10) and (16) opcodes, when they are reported to be supported. If not, should we go for SD_MAX_WS16_BLOCKS instead when WRITE SAME (16) is supported? P.S. Please be noted I have been talking about cases when the Maximum Write Same Length reported in the Block Limit VPD is 0. On 27 February 2016 at 04:07, <tom.ty89@xxxxxxxxx> wrote: > From: Tom Yan <tom.ty89@xxxxxxxxx> > > Example: > > [root@localhost ~]# sg_opcodes /dev/sdb > /dev/null > Report supported operation codes: Illegal request, invalid opcode > > [root@localhost ~]# sg_vpd -p bl /dev/sdb | grep 'write same' > Maximum write same length: 0x0 blocks > > [root@localhost ~]# cat /sys/block/sdb/queue/write_same_max_bytes > 33553920 > > Signed-off-by: Tom Yan <tom.ty89@xxxxxxxxx> > > diff --git a/drivers/scsi/sd.c b/drivers/scsi/sd.c > index d749da7..1179ec1 100644 > --- a/drivers/scsi/sd.c > +++ b/drivers/scsi/sd.c > @@ -807,6 +807,8 @@ static void sd_config_write_same(struct scsi_disk *sdkp) > if (sdkp->max_ws_blocks > SD_MAX_WS10_BLOCKS) > sdkp->max_ws_blocks = min_not_zero(sdkp->max_ws_blocks, > (u32)SD_MAX_WS16_BLOCKS); > + else if (sdkp->max_ws_blocks == 0 && sdkp->device->no_report_opcodes) > + sdkp->device->no_write_same = 1; > else if (sdkp->ws16 || sdkp->ws10 || sdkp->device->no_report_opcodes) > sdkp->max_ws_blocks = min_not_zero(sdkp->max_ws_blocks, > (u32)SD_MAX_WS10_BLOCKS); > -- > 2.7.1 > -- To unsubscribe from this list: send the line "unsubscribe linux-scsi" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
