From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (qmail 2019 invoked by alias); 23 Feb 2012 17:36:40 -0000 Received: (qmail 2002 invoked by uid 9478); 23 Feb 2012 17:36:38 -0000 Date: Thu, 23 Feb 2012 17:36:00 -0000 Message-ID: <20120223173638.2000.qmail@sourceware.org> From: jbrassow@sourceware.org To: lvm-devel@redhat.com, lvm2-cvs@sourceware.org Subject: LVM2 ./WHATS_NEW lib/metadata/lv_manip.c lib/m ... Mailing-List: contact lvm2-cvs-help@sourceware.org; run by ezmlm Precedence: bulk List-Id: List-Subscribe: List-Post: List-Help: , Sender: lvm2-cvs-owner@sourceware.org X-SW-Source: 2012-02/txt/msg00152.txt.bz2 CVSROOT: /cvs/lvm2 Module name: LVM2 Changes by: jbrassow@sourceware.org 2012-02-23 17:36:37 Modified files: . : WHATS_NEW lib/metadata : lv_manip.c raid_manip.c tools : lvcreate.c Log message: Require number of stripes to be greater than parity devices in higher RAID. Also, add some comments to code that I recently added that may be unclear otherwise. Patches: http://sourceware.org/cgi-bin/cvsweb.cgi/LVM2/WHATS_NEW.diff?cvsroot=lvm2&r1=1.2303&r2=1.2304 http://sourceware.org/cgi-bin/cvsweb.cgi/LVM2/lib/metadata/lv_manip.c.diff?cvsroot=lvm2&r1=1.364&r2=1.365 http://sourceware.org/cgi-bin/cvsweb.cgi/LVM2/lib/metadata/raid_manip.c.diff?cvsroot=lvm2&r1=1.23&r2=1.24 http://sourceware.org/cgi-bin/cvsweb.cgi/LVM2/tools/lvcreate.c.diff?cvsroot=lvm2&r1=1.254&r2=1.255 --- LVM2/WHATS_NEW 2012/02/23 11:24:07 1.2303 +++ LVM2/WHATS_NEW 2012/02/23 17:36:35 1.2304 @@ -1,5 +1,6 @@ Version 2.02.93 - ==================================== + Require number of stripes to be greater than parity devices in higher RAID. Add LVMetaD systemd units. Fix allocation code to allow replacement of single RAID 4/5/6 device. Check all tags and LV names are in a valid form in vg_validate. --- LVM2/lib/metadata/lv_manip.c 2012/02/23 03:57:23 1.364 +++ LVM2/lib/metadata/lv_manip.c 2012/02/23 17:36:36 1.365 @@ -752,6 +752,22 @@ area_count = stripes; size = sizeof(*ah); + + /* + * It is a requirement that RAID 4/5/6 are created with a number of + * stripes that is greater than the number of parity devices. (e.g + * RAID4/5 must have at least 2 stripes and RAID6 must have at least + * 3.) It is also a constraint that, when replacing individual devices + * in a RAID 4/5/6 array, no more devices can be replaced than + * there are parity devices. (Otherwise, there would not be enough + * redundancy to maintain the array.) Understanding these two + * constraints allows us to infer whether the caller of this function + * is intending to allocate an entire array or just replacement + * component devices. In the former case, we must account for the + * necessary parity_count. In the later case, we do not need to + * account for the extra parity devices because the array already + * exists and they only want replacement drives. + */ parity_count = (area_count <= segtype->parity_devs) ? 0 : segtype->parity_devs; alloc_count = area_count + parity_count; --- LVM2/lib/metadata/raid_manip.c 2012/02/23 03:57:23 1.23 +++ LVM2/lib/metadata/raid_manip.c 2012/02/23 17:36:36 1.24 @@ -519,9 +519,18 @@ else if (!(segtype = get_segtype_from_string(lv->vg->cmd, "raid1"))) return_0; + /* + * The number of extents is based on the RAID type. For RAID1, + * each of the rimages is the same size - 'le_count'. However + * for RAID 4/5/6, the stripes add together (NOT including the parity + * devices) to equal 'le_count'. Thus, when we are allocating + * individual devies, we must specify how large the individual device + * is along with the number we want ('count'). + */ extents = (segtype->parity_devs) ? (lv->le_count / (seg->area_count - segtype->parity_devs)) : lv->le_count; + if (!(ah = allocate_extents(lv->vg, NULL, segtype, 0, count, count, region_size, extents, pvs, lv->alloc, parallel_areas))) --- LVM2/tools/lvcreate.c 2012/02/15 15:18:44 1.254 +++ LVM2/tools/lvcreate.c 2012/02/23 17:36:36 1.255 @@ -485,9 +485,10 @@ * * For RAID 4/5/6, these values must be set. */ - if (!segtype_is_mirrored(lp->segtype) && (lp->stripes < 2)) { - log_error("Number of stripes to %s not specified", - lp->segtype->name); + if (!segtype_is_mirrored(lp->segtype) && + (lp->stripes <= lp->segtype->parity_devs)) { + log_error("Number of stripes must be at least %d for %s", + lp->segtype->parity_devs + 1, lp->segtype->name); return 0; }