From mboxrd@z Thu Jan 1 00:00:00 1970 From: "Ewan D. Milne" Subject: Re: [PATCH] scsi: sd: Implement blacklist option for WRITE SAME w/ UNMAP Date: Thu, 28 Sep 2017 11:46:21 -0400 Message-ID: <1506613581.4100.504.camel@localhost.localdomain> References: <1506529677.4100.452.camel@localhost.localdomain> <20170928013512.1058-1-martin.petersen@oracle.com> Reply-To: emilne@redhat.com Mime-Version: 1.0 Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: 7bit Return-path: Received: from mx1.redhat.com ([209.132.183.28]:58038 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750763AbdI1PqW (ORCPT ); Thu, 28 Sep 2017 11:46:22 -0400 In-Reply-To: <20170928013512.1058-1-martin.petersen@oracle.com> Sender: linux-scsi-owner@vger.kernel.org List-Id: linux-scsi@vger.kernel.org To: "Martin K. Petersen" Cc: linux-scsi@vger.kernel.org On Wed, 2017-09-27 at 21:35 -0400, Martin K. Petersen wrote: > SBC-4 states: > > "A MAXIMUM UNMAP LBA COUNT field set to a non-zero value indicates the > maximum number of LBAs that may be unmapped by an UNMAP command" > > "A MAXIMUM WRITE SAME LENGTH field set to a non-zero value indicates > the maximum number of contiguous logical blocks that the device server > allows to be unmapped or written in a single WRITE SAME command." > > Despite the spec being clear on the topic, some devices incorrectly > expect WRITE SAME commands with the UNMAP bit set to be limited to the > value reported in MAXIMUM UNMAP LBA COUNT in the Block Limits VPD. > > Implement a blacklist option that can be used to accommodate devices > with this behavior. > > Reported-by: Bill Kuzeja > Reported-by: Ewan D. Milne > Signed-off-by: Martin K. Petersen > --- > drivers/scsi/scsi_scan.c | 3 +++ > drivers/scsi/sd.c | 16 ++++++++++++---- > include/scsi/scsi_device.h | 1 + > include/scsi/scsi_devinfo.h | 1 + > 4 files changed, 17 insertions(+), 4 deletions(-) > > diff --git a/drivers/scsi/scsi_scan.c b/drivers/scsi/scsi_scan.c > index e7818afeda2b..15590a063ad9 100644 > --- a/drivers/scsi/scsi_scan.c > +++ b/drivers/scsi/scsi_scan.c > @@ -956,6 +956,9 @@ static int scsi_add_lun(struct scsi_device *sdev, unsigned char *inq_result, > if (*bflags & BLIST_NO_DIF) > sdev->no_dif = 1; > > + if (*bflags & BLIST_UNMAP_LIMIT_WS) > + sdev->unmap_limit_for_ws = 1; > + > sdev->eh_timeout = SCSI_DEFAULT_EH_TIMEOUT; > > if (*bflags & BLIST_TRY_VPD_PAGES) > diff --git a/drivers/scsi/sd.c b/drivers/scsi/sd.c > index b18ba3235900..347be7580181 100644 > --- a/drivers/scsi/sd.c > +++ b/drivers/scsi/sd.c > @@ -715,13 +715,21 @@ static void sd_config_discard(struct scsi_disk *sdkp, unsigned int mode) > break; > > case SD_LBP_WS16: > - max_blocks = min_not_zero(sdkp->max_ws_blocks, > - (u32)SD_MAX_WS16_BLOCKS); > + if (sdkp->device->unmap_limit_for_ws) > + max_blocks = sdkp->max_unmap_blocks; > + else > + max_blocks = sdkp->max_ws_blocks; > + > + max_blocks = min_not_zero(max_blocks, (u32)SD_MAX_WS16_BLOCKS); > break; > > case SD_LBP_WS10: > - max_blocks = min_not_zero(sdkp->max_ws_blocks, > - (u32)SD_MAX_WS10_BLOCKS); > + if (sdkp->device->unmap_limit_for_ws) > + max_blocks = sdkp->max_unmap_blocks; > + else > + max_blocks = sdkp->max_ws_blocks; > + > + max_blocks = min_not_zero(max_blocks, (u32)SD_MAX_WS10_BLOCKS); > break; > > case SD_LBP_ZERO: > diff --git a/include/scsi/scsi_device.h b/include/scsi/scsi_device.h > index 82e93ee94708..67c5a9f223f7 100644 > --- a/include/scsi/scsi_device.h > +++ b/include/scsi/scsi_device.h > @@ -192,6 +192,7 @@ struct scsi_device { > unsigned no_dif:1; /* T10 PI (DIF) should be disabled */ > unsigned broken_fua:1; /* Don't set FUA bit */ > unsigned lun_in_cdb:1; /* Store LUN bits in CDB[1] */ > + unsigned unmap_limit_for_ws:1; /* Use the UNMAP limit for WRITE SAME */ > > atomic_t disk_events_disable_depth; /* disable depth for disk events */ > > diff --git a/include/scsi/scsi_devinfo.h b/include/scsi/scsi_devinfo.h > index 9592570e092a..36b03013d629 100644 > --- a/include/scsi/scsi_devinfo.h > +++ b/include/scsi/scsi_devinfo.h > @@ -29,5 +29,6 @@ > #define BLIST_TRY_VPD_PAGES 0x10000000 /* Attempt to read VPD pages */ > #define BLIST_NO_RSOC 0x20000000 /* don't try to issue RSOC */ > #define BLIST_MAX_1024 0x40000000 /* maximum 1024 sector cdb length */ > +#define BLIST_UNMAP_LIMIT_WS 0x80000000 /* Use UNMAP limit for WRITE SAME */ > > #endif Thanks. Reviewed-by: Ewan D. Milne