> -----Original Message----- > From: Douglas Gilbert [mailto:dgilbert@xxxxxxxxxxxx] > Sent: Saturday, March 17, 2012 2:56 PM > To: Jeff Garzik > Cc: KY Srinivasan; gregkh@xxxxxxxxxxxxxxxxxxx; linux-kernel@xxxxxxxxxxxxxxx; > devel@xxxxxxxxxxxxxxxxxxxxxx; virtualization@xxxxxxxxxxxxxx; ohering@xxxxxxxx; > jbottomley@xxxxxxxxxxxxx; hch@xxxxxxxxxxxxx; linux-scsi@xxxxxxxxxxxxxxx > Subject: Re: [PATCH 2/2] Drivers: scsi: storvsc: Don't pass ATA_16 command to > the host > > On 12-03-17 04:04 PM, Jeff Garzik wrote: > > On 03/16/2012 04:24 PM, K. Y. Srinivasan wrote: > >> The current Windows hosts don't handle the ATA_16 command and > furthermore > >> return a generic error code after filtering the command on the host side. > >> For now filter the command on the guest side until the host is modified to > >> properly handle unsupported commands. > >> > >> Signed-off-by: K. Y. Srinivasan<kys@xxxxxxxxxxxxx> > >> Reviewed-by: Haiyang Zhang<haiyangz@xxxxxxxxxxxxx> > >> --- > >> drivers/scsi/storvsc_drv.c | 9 +++++++++ > >> 1 files changed, 9 insertions(+), 0 deletions(-) > >> > >> diff --git a/drivers/scsi/storvsc_drv.c b/drivers/scsi/storvsc_drv.c > >> index 8b967c9..783bab8 100644 > >> --- a/drivers/scsi/storvsc_drv.c > >> +++ b/drivers/scsi/storvsc_drv.c > >> @@ -1229,8 +1229,17 @@ static bool storvsc_scsi_cmd_ok(struct scsi_cmnd > *scmnd) > >> /* > >> * smartd sends this command and the host does not handle > >> * this. So, don't send it. > >> + * The current Windows hosts implement a subset of scsi commands > >> + * and for the commands that are not implemented, the host filters > >> + * them and returns a generic failure SRB status. I have been in > >> + * discussions with the Windows team to return the appropriate SRB > >> + * status code for unsupported scsi commands and while they have > >> + * agreed to implement this, it is not clear when this change will be > >> + * available. Consequently, filtering the command before submitting it > >> + * to the host is a resonable interim solution. > >> */ > >> case SET_WINDOW: > >> + case ATA_16: > >> scmnd->result = ILLEGAL_REQUEST<< 16; > >> allowed = false; > > > > It would be even nicer to fill out a nice SCSI status for this. For an illegal > > request such as this, the libata SCSI simulator (drivers/ata/libata-scsi.c) uses > > a more complete sense buffer setup, > > > > static void ata_scsi_set_sense(struct scsi_cmnd *cmd, u8 sk, > > u8 asc, u8 ascq) > > { > > cmd->result = (DRIVER_SENSE << 24) | SAM_STAT_CHECK_CONDITION; > > > > scsi_build_sense_buffer(0, cmd->sense_buffer, sk, asc, ascq); > > } > > > > and calls this function for invalid/unknown/unsupported command ops thusly, > > > > ata_scsi_set_sense(cmd, ILLEGAL_REQUEST, 0x20, 0x0); > > /* "Invalid command operation code" */ > > > > Supplying asc/ascq provides additional information that may be useful in > > determining whether or not to retry, provide better error diagnostics, etc. > > > > The asc/ascq values are found in the SCSI standards documents. > > Jeff, > I agree with your suggestion and would point out that the > originally proposed: > scmnd->result = ILLEGAL_REQUEST<< 16; > > is just plain wrong. result[23:16] is a Linux invented host byte > code (they typically start with "DID_") while ILLEGAL_REQUEST is > a SCSI sense key. > > Doug Gilbert > Jeff, Doug, Thank you. I will make the suggested changes. Regards, K. Y _______________________________________________ devel mailing list devel@xxxxxxxxxxxxxxxxxxxxxx http://driverdev.linuxdriverproject.org/mailman/listinfo/devel
