From mboxrd@z Thu Jan 1 00:00:00 1970 From: Lidong Zhong Subject: Re: [PATCH v3] super1: fix sb->max_dev when adding a new disk in linear array Date: Mon, 22 May 2017 11:28:25 +0800 Message-ID: <86430c3a-73ed-4c9b-3386-c76b0ee82e82@suse.com> References: <20170519060638.4470-1-lzhong@suse.com> <87lgppkcrn.fsf@notabene.neil.brown.name> Mime-Version: 1.0 Content-Type: text/plain; charset=windows-1252; format=flowed Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <87lgppkcrn.fsf@notabene.neil.brown.name> Sender: linux-raid-owner@vger.kernel.org To: NeilBrown , linux-raid@vger.kernel.org Cc: colyli@suse.com, Jes.Sorensen@gmail.com List-Id: linux-raid.ids On 05/22/2017 07:31 AM, NeilBrown wrote: > On Fri, May 19 2017, Lidong Zhong wrote: > >> The value of sb->max_dev will always be increased by 1 when adding >> a new disk in linear array. It causes an inconsistence between each >> disk in the array and the "Array State" value of "mdadm --examine DISK" >> is wrong. For example, when adding the first new disk into linear array >> it will be: >> >> Array State : RAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA >> ('A' == active, '.' == missing, 'R' == replacing) >> >> Adding the second disk into linear array it will be >> >> Array State : .AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA >> ('A' == active, '.' == missing, 'R' == replacing) >> >> Signed-off-by: Lidong Zhong >> --- >> super1.c | 13 +++++++++++-- >> 1 file changed, 11 insertions(+), 2 deletions(-) >> >> diff --git a/super1.c b/super1.c >> index 2fcb814..811923f 100644 >> --- a/super1.c >> +++ b/super1.c >> @@ -1267,8 +1267,13 @@ static int update_super1(struct supertype *st, struct mdinfo *info, >> break; >> sb->dev_number = __cpu_to_le32(i); >> info->disk.number = i; >> - if (max >= __le32_to_cpu(sb->max_dev)) >> - sb->max_dev = __cpu_to_le32(max+1); >> + if (i >= max) { >> + while (max <= i) { >> + sb->dev_roles[max] = __cpu_to_le16(MD_DISK_ROLE_SPARE); >> + max += 1; >> + } >> + sb->max_dev = __cpu_to_le32(max); >> + } > > This part of the patch is OK.... > >> >> random_uuid(sb->device_uuid); >> >> @@ -1296,6 +1301,10 @@ static int update_super1(struct supertype *st, struct mdinfo *info, >> sb->raid_disks = __cpu_to_le32(info->array.raid_disks); >> sb->dev_roles[info->disk.number] = >> __cpu_to_le16(info->disk.raid_disk); >> + if (sb->raid_disks+1 >= __le32_to_cpu(sb->max_dev)) { > > sb->raid_disks is an le32 number, not a cpu number. So adding 1 to > it is clearly wrong. > Really sorry for the careless...I mean info->array.raid_disks here. > Why do you think you need a change here at all? > The first part of this patch is dealing with the newly added disk when the disk number is greater than sb->max_dev. While updating the superblock on the original disks of the linear array, shouldn't I also check if the disk numbers is greater than sb->max_dev? 254 info.array.raid_disks = nd+1; 255 info.array.nr_disks = nd+1; 256 info.array.active_disks = nd+1; 257 info.array.working_disks = nd+1; 258 259 st->ss->update_super(st, &info, "linear-grow-update", dv, 260 0, 0, NULL); 261 262 if (st->ss->store_super(st, fd2)) { 263 pr_err("Cannot store new superblock on %s\n", dv); 264 close(fd2); 265 return 1; 266 } Thanks, Lidong > NeilBrown > > >> + sb->dev_roles[sb->raid_disks] = __cpu_to_le16(MD_DISK_ROLE_SPARE); >> + sb->max_dev = __cpu_to_le32(sb->raid_disks+1); >> + } >> } else if (strcmp(update, "resync") == 0) { >> /* make sure resync happens */ >> sb->resync_offset = 0ULL; >> -- >> 2.12.0