From owner-svn-src-all@FreeBSD.ORG Sun Oct 24 17:58:55 2010 Return-Path: Delivered-To: svn-src-all@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34]) by hub.freebsd.org (Postfix) with ESMTP id F2867106566C; Sun, 24 Oct 2010 17:58:54 +0000 (UTC) (envelope-from yanegomi@gmail.com) Received: from mail-wy0-f182.google.com (mail-wy0-f182.google.com [74.125.82.182]) by mx1.freebsd.org (Postfix) with ESMTP id 0C3D58FC12; Sun, 24 Oct 2010 17:58:53 +0000 (UTC) Received: by wyb42 with SMTP id 42so2589317wyb.13 for ; Sun, 24 Oct 2010 10:58:53 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=gamma; h=domainkey-signature:mime-version:received:sender:received :in-reply-to:references:date:x-google-sender-auth:message-id:subject :from:to:cc:content-type:content-transfer-encoding; bh=6kjr9i32ab5fHwYwIVchjyD9CvV35F65tFSJKzia9II=; b=SPOe/DUkwXM6RGzpIssy//ILX+JsNyEZVpk3g5xLsIEo2v8CF2XUN60MC6vqHTKDSL w9XyIwb9sLspodpQcBZq9x0akfReBZfr3t26V5mC5EHZHI2gB03nrQCb0kUlKEmoqeQd +K4s64aCWIgZDrobYHMoPtBRiiSZ9pGgGOsdY= DomainKey-Signature: a=rsa-sha1; c=nofws; d=gmail.com; s=gamma; h=mime-version:sender:in-reply-to:references:date :x-google-sender-auth:message-id:subject:from:to:cc:content-type :content-transfer-encoding; b=XCgrs+OxwfcaQCJ4nUgF5w94OGx3W2FDjAIgSBrdlLZWElwl0QmjnZGQmy3LMCODv8 QjeKDCmkib3it7y0ZQKvEXWTwFSAOg0n5WqixqjcKo3HfCtSuojyuo7U2iIcr6Rae3YL oSppMhd3u/z9OteLmdOv8utB1psBpVmOiPHd0= MIME-Version: 1.0 Received: by 10.216.188.197 with SMTP id a47mr5168480wen.70.1287943132906; Sun, 24 Oct 2010 10:58:52 -0700 (PDT) Sender: yanegomi@gmail.com Received: by 10.216.10.198 with HTTP; Sun, 24 Oct 2010 10:58:52 -0700 (PDT) In-Reply-To: <4CC47301.9020609@FreeBSD.org> References: <201010241631.o9OGVw1C033817@svn.freebsd.org> <201010241735.32876.bruce@cran.org.uk> <4CC466D5.6080306@FreeBSD.org> <4CC47301.9020609@FreeBSD.org> Date: Sun, 24 Oct 2010 10:58:52 -0700 X-Google-Sender-Auth: KbrTlV6qYtzOfp6kVVNG4ndNQ64 Message-ID: From: Garrett Cooper To: Alexander Motin Content-Type: text/plain; charset=windows-1252 Content-Transfer-Encoding: quoted-printable Cc: Bruce Cran , svn-src-head@freebsd.org, svn-src-all@freebsd.org, src-committers@freebsd.org Subject: Re: svn commit: r214279 - in head: share/man/man4 sys/cam sys/cam/ata sys/kern X-BeenThere: svn-src-all@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: "SVN commit messages for the entire src tree \(except for " user" and " projects" \)" List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Sun, 24 Oct 2010 17:58:55 -0000 On Sun, Oct 24, 2010 at 10:55 AM, Alexander Motin wrote: > Garrett Cooper wrote: >> On Sun, Oct 24, 2010 at 10:03 AM, Alexander Motin wrot= e: >>> Bruce Cran wrote: >>>> On Sunday 24 October 2010 17:31:58 Bruce Cran wrote: >>>> >>>>> Log: >>>>> =A0 Mostly revert r203420, and add similar functionality into ada(4) = since >>>>> the existing code caused problems with some SCSI controllers. >>> Proper way would be IMHO to fix polling in aac driver. >>> >>>>> =A0 A new sysctl kern.cam.ada.spindown_shutdown has been added that c= ontrols >>>>> =A0 whether or not to spin-down disks when shutting down. >>>>> =A0 Spinning down the disks unloads/parks the heads - this is >>>>> =A0 much better than removing power when the disk is still >>>>> =A0 spinning because otherwise an Emergency Unload occurs which may c= ause >>>>> damage to the actuator. >>>> The FLUSH CACHE + STANDBY IMMEDIATE commands are issued (instead of ju= st >>>> SLEEP) following the procedure documented in Fujitsu's MHW series prod= uct >>>> documentation under section 1.10.1, "Recommended power-off sequence". >>> Not instead of "just SLEEP", but instead of FLUSH CACHE (by respective >>> peripheral driver) + SLEEP (by xpt). It should probably be the same. >>> >>> Just for the note, SCSI specification states that STOP automatically >>> implies FLUSH CACHE. ATA - doesn't. >> >> =A0 =A0 I could be wrong, but I think the ANSI ATA<->SCSI spec states >> otherwise (taken from ANSI INCITS 431-2007 page 62 -- see steps 1-4): >> >> 9.11.3 START STOP UNIT START bit LOEJ bit combinations >> The SATL shall perform the actions shown in table 40 in response to a >> START STOP UNIT command. >> Table 40 =97 Definition of START and LOEJ bits in the START STOP UNIT CD= B >> START LOEJ Definition >> 0 0 The SATL shall: >> 1) If the IMMED bit is set to one, then return GOOD status; >> 2) Issue an ATA flush command (see 3.1.11) to the ATA device; >> 3) If the ATA flush command completes with any error, then process endin= g status >> according to the IMMED bit (see 9.11.2) with the additional sense code s= et to >> COMMAND SEQUENCE ERROR; >> 4) If the ATA flush command completes without error, then issue an ATA S= TANDBY >> IMMEDIATE command to the ATA Sector Count set to zero; >> 5) If the ATA STANDBY IMMEDIATE command completes with any error, then >> process ending status according to the IMMED bit (see 9.11.2) with the >> additional >> sense code set to COMMAND SEQUENCE ERROR; and >> 6) If the ATA STANDBY IMMEDIATE command completes without error and the >> IMMED bit is set to zero, then return GOOD status (see 9.11.2) a. >> >> =A0 =A0 Not sure about the ATA spec standalone... might be present in th= e ATA8 spec. > > As I understand, this just confirms what I have said: > SCSI STOP =3D=3D ATA FLUSH CACHE + STANDBY IMMEDIATE. > So SCSI STOP implies flush, while ATA STANDBY IMMEDIATE doesn't. Looking at it from that perspective, I agree.