From: "Martin K. Petersen" <martin.petersen@oracle.com>
To: "hch@infradead.org" <hch@infradead.org>
Cc: "linux-scsi@vger.kernel.org" <linux-scsi@vger.kernel.org>,
"Martin K. Petersen" <martin.petersen@oracle.com>,
"jasowang@redhat.com" <jasowang@redhat.com>,
"linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
James Bottomley <jbottomley@parallels.com>,
"ohering@suse.com" <ohering@suse.com>,
"stable@vger.kernel.org" <stable@vger.kernel.org>,
"apw@canonical.com" <apw@canonical.com>,
"devel@linuxdriverproject.org" <devel@linuxdriverproject.org>
Subject: Re: [PATCH 4/8] Drivers: scsi: storvsc: Filter WRITE_SAME_16
Date: Wed, 16 Jul 2014 11:44:18 -0400 [thread overview]
Message-ID: <yq14myhtijx.fsf@sermon.lab.mkp.net> (raw)
In-Reply-To: <20140716110111.GA7382@infradead.org> (hch@infradead.org's message of "Wed, 16 Jul 2014 04:01:11 -0700")
>>>>> "hch" == hch@infradead org <hch@infradead.org> writes:
hch> read_capacity_16 calls sd_config_discard(sdkp, SD_LBP_WS16) if the
hch> LPBME bit is set. At least older SBC drafts left it wide open if a
hch> target supports WRITE SAME with UNMAP or UNMAP in this case.
Correct.
hch> So I think we'd still want a patch to use UNMAP instead of WRITE
hch> SAME for this case, which should also fix hyperv.
There are lots of devices out there that support WRITE SAME(10) or (16)
without the UNMAP bit. And there are devices that support WRITE SAME w/
UNMAP functionality but not "regular" WRITE SAME.
no_write_same is there to prevent the REQ_WRITE_SAME use case (for which
we have really weak heuristics). Your patch overloads no_write_same so
it also governs a REQ_DISCARD use case.
My proposed black list patch fixes the hyperv discard issue. So I don't
see why we'd need to overload no_write_same which was meant for an
entirely different purpose.
--
Martin K. Petersen Oracle Linux Engineering
next prev parent reply other threads:[~2014-07-16 15:44 UTC|newest]
Thread overview: 68+ messages / expand[flat|nested] mbox.gz Atom feed top
2014-07-09 0:46 [PATCH 0/8] Drivers: scsi: storvsc: Bug fixes and improvements K. Y. Srinivasan
2014-07-09 0:46 ` [PATCH 1/8] Drivers: scsi: storvsc: Change the limits to reflect the values on the host K. Y. Srinivasan
2014-07-09 0:46 ` [PATCH 2/8] Drivers: scsi: storvsc: Filter commands based on the storage protocol version K. Y. Srinivasan
2014-07-09 8:40 ` Christoph Hellwig
2014-07-09 20:02 ` KY Srinivasan
2014-07-09 0:46 ` [PATCH 3/8] Drivers: scsi: storvsc: Fix a bug in handling VMBUS " K. Y. Srinivasan
2014-07-09 8:41 ` Christoph Hellwig
2014-07-09 20:01 ` KY Srinivasan
2014-07-09 0:46 ` [PATCH 4/8] Drivers: scsi: storvsc: Filter WRITE_SAME_16 K. Y. Srinivasan
2014-07-09 8:43 ` Christoph Hellwig
2014-07-09 19:52 ` KY Srinivasan
2014-07-09 19:56 ` James Bottomley
2014-07-09 21:14 ` KY Srinivasan
2014-07-09 22:27 ` James Bottomley
2014-07-09 22:36 ` KY Srinivasan
2014-07-10 10:07 ` hch
2014-07-10 21:02 ` KY Srinivasan
2014-07-10 22:12 ` James Bottomley
2014-07-11 6:32 ` hch
2014-07-11 12:54 ` Martin K. Petersen
2014-07-12 2:53 ` KY Srinivasan
2014-07-12 2:50 ` KY Srinivasan
2014-07-13 12:58 ` Martin K. Petersen
2014-07-13 18:49 ` KY Srinivasan
2014-07-14 2:37 ` KY Srinivasan
2014-07-14 3:19 ` KY Srinivasan
2014-07-16 11:01 ` hch
2014-07-16 14:53 ` James Bottomley
2014-07-16 15:44 ` Martin K. Petersen [this message]
2014-07-16 17:38 ` hch
2014-07-16 17:47 ` Martin K. Petersen
2014-07-16 17:55 ` hch
2014-07-16 18:02 ` James Bottomley
2014-07-16 18:43 ` Elliott, Robert (Server Storage)
2014-07-16 19:20 ` Martin K. Petersen
2014-07-17 7:42 ` hch
2014-07-17 12:41 ` Martin K. Petersen
2014-07-16 18:45 ` Martin K. Petersen
2014-07-16 18:50 ` James Bottomley
2014-07-16 19:08 ` Martin K. Petersen
2014-07-16 19:14 ` James Bottomley
2014-07-16 19:44 ` Martin K. Petersen
2014-07-09 0:46 ` [PATCH 5/8] Drivers: scsi: storvsc: Fix a bug in the handling of SRB status flags K. Y. Srinivasan
2014-07-09 8:43 ` Christoph Hellwig
2014-07-09 0:46 ` [PATCH 6/8] Drivers: scsi: storvsc: Implement an abort handler K. Y. Srinivasan
2014-07-09 8:44 ` Christoph Hellwig
2014-07-09 18:51 ` KY Srinivasan
2014-07-10 10:13 ` Christoph Hellwig
2014-07-10 22:26 ` KY Srinivasan
2014-07-11 9:52 ` Hannes Reinecke
2014-07-11 9:54 ` Christoph Hellwig
2014-07-11 14:49 ` KY Srinivasan
2014-07-10 10:33 ` Richard Weinberger
2014-07-12 16:16 ` Richard Weinberger
2014-07-12 16:35 ` KY Srinivasan
2014-07-09 0:46 ` [PATCH 7/8] drivers: scsi: storvsc: Set srb_flags in all cases K. Y. Srinivasan
2014-07-09 8:44 ` Christoph Hellwig
2014-07-09 18:40 ` KY Srinivasan
2014-07-10 10:17 ` Christoph Hellwig
2014-07-10 22:22 ` KY Srinivasan
2014-07-10 10:18 ` Christoph Hellwig
2014-07-11 21:03 ` KY Srinivasan
2014-07-09 0:46 ` [PATCH 8/8] drivers: scsi: storvsc: Correctly handle TEST_UNIT_READY failure K. Y. Srinivasan
2014-07-09 8:46 ` Christoph Hellwig
2014-07-09 18:35 ` KY Srinivasan
2014-07-09 8:39 ` [PATCH 1/8] Drivers: scsi: storvsc: Change the limits to reflect the values on the host Christoph Hellwig
2014-07-09 20:07 ` KY Srinivasan
2014-07-09 23:39 ` KY Srinivasan
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