From: Jonathan Brassow This patch adds extra information to the mirror status output, so that it can be determined which device(s) have failed. An 'A' for alive and 'D' for dead are printed in the status line for each mirror device. This allows userspace to properly reconfigure the mirror set. --- drivers/md/dm-raid1.c | 11 ++++++++--- 1 files changed, 8 insertions(+), 3 deletions(-) Index: linux-2.6.23/drivers/md/dm-raid1.c =================================================================== --- linux-2.6.23.orig/drivers/md/dm-raid1.c 2007-10-13 06:48:56.000000000 +0100 +++ linux-2.6.23/drivers/md/dm-raid1.c 2007-10-13 06:48:58.000000000 +0100 @@ -1481,17 +1481,22 @@ static int mirror_status(struct dm_targe { unsigned int m, sz = 0; struct mirror_set *ms = (struct mirror_set *) ti->private; + char buffer[ms->nr_mirrors + 1]; switch (type) { case STATUSTYPE_INFO: DMEMIT("%d ", ms->nr_mirrors); - for (m = 0; m < ms->nr_mirrors; m++) + for (m = 0; m < ms->nr_mirrors; m++) { DMEMIT("%s ", ms->mirror[m].dev->name); + buffer[m] = atomic_read(&(ms->mirror[m].error_count)) ? + 'D' : 'A'; + } + buffer[m] = '\0'; - DMEMIT("%llu/%llu 0 ", + DMEMIT("%llu/%llu 1 %s ", (unsigned long long)ms->rh.log->type-> get_sync_count(ms->rh.log), - (unsigned long long)ms->nr_regions); + (unsigned long long)ms->nr_regions, buffer); sz += ms->rh.log->type->status(ms->rh.log, type, result+sz, maxlen-sz);