From mboxrd@z Thu Jan 1 00:00:00 1970 From: Sergei Shtylyov Subject: Re: SATA: Is "DPO and FUA" ever supported? Date: Fri, 22 Jun 2007 18:15:08 +0400 Message-ID: <467BD96C.4090005@ru.mvista.com> References: <467A7D5A.9070009@msgid.tls.msk.ru> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii; format=flowed Content-Transfer-Encoding: 7bit Return-path: Received: from homer.mvista.com ([63.81.120.155]:8426 "EHLO imap.sh.mvista.com" rhost-flags-OK-FAIL-OK-FAIL) by vger.kernel.org with ESMTP id S1753816AbXFVON0 (ORCPT ); Fri, 22 Jun 2007 10:13:26 -0400 In-Reply-To: <467A7D5A.9070009@msgid.tls.msk.ru> Sender: linux-ide-owner@vger.kernel.org List-Id: linux-ide@vger.kernel.org To: Michael Tokarev Cc: linux-ide@vger.kernel.org Hello. Michael Tokarev wrote: > On each and every machine out there, and on every dmesg > output posted on numerous mailinglists, I see messages > similar to this: > scsi 0:0:0:0: Direct-Access ATA ST3250620NS 3.AE PQ: 0 ANSI: 5 > SCSI device sda: 488397168 512-byte hdwr sectors (250059 MB) > SCSI device sda: write cache: enabled, read cache: enabled, doesn't support DPO or FUA > for SATA disk drives. And I wonder -- are those features > supported at all by linux, and/or are there disk drives > out there which supports it as well? Don't know, the bits have just quite recently been included into ATA spec, IIRC... > For my Seagate ST3250620NS SATA drive (it's a "server" drive, > whatever it means), I can see -- at least -- > * Mandatory FLUSH_CACHE > * FLUSH_CACHE_EXT > reported by hdparm -I. I wonder what "FLUSH CACHE EXT" means, It reports LBA48 of a failing sector while FLUSH CACHE can only report LBA28. > and whenever it can be used to support DPO and/or FUA... DPO and FUA bits are a part of SCSI CDB and so only affect the block range specified by the command in question while FLUSH CACHE [EXT] operates on the whole cache -- so, it's not equivalent. > Thanks. > > /mjt MBR, Sergei