From 78d8e58a086b214dddf1fd463e20a7e1d82d7866 Mon Sep 17 00:00:00 2001 From: Mike Snitzer Date: Fri, 26 Jun 2015 10:01:13 -0400 Subject: Revert "block, dm: don't copy bios for request clones" This reverts commit 5f1b670d0bef508a5554d92525f5f6d00d640b38. Justification for revert as reported in this dm-devel post: https://www.redhat.com/archives/dm-devel/2015-June/msg00160.html this change should not be pushed to mainline yet. Firstly, Christoph has a newer version of the patch that fixes silent data corruption problem: https://www.redhat.com/archives/dm-devel/2015-May/msg00229.html And the new version still depends on LLDDs to always complete requests to the end when error happens, while block API doesn't enforce such a requirement. If the assumption is ever broken, the inconsistency between request and bio (e.g. rq->__sector and rq->bio) will cause silent data corruption: https://www.redhat.com/archives/dm-devel/2015-June/msg00022.html Reported-by: Junichi Nomura Signed-off-by: Mike Snitzer --- drivers/md/dm-table.c | 25 +++++++++---------------- 1 file changed, 9 insertions(+), 16 deletions(-) (limited to 'drivers/md/dm-table.c') diff --git a/drivers/md/dm-table.c b/drivers/md/dm-table.c index a5f94125ad01..16ba55ad7089 100644 --- a/drivers/md/dm-table.c +++ b/drivers/md/dm-table.c @@ -942,28 +942,21 @@ static int dm_table_alloc_md_mempools(struct dm_table *t, struct mapped_device * { unsigned type = dm_table_get_type(t); unsigned per_bio_data_size = 0; + struct dm_target *tgt; unsigned i; - switch (type) { - case DM_TYPE_BIO_BASED: - for (i = 0; i < t->num_targets; i++) { - struct dm_target *tgt = t->targets + i; - - per_bio_data_size = max(per_bio_data_size, - tgt->per_bio_data_size); - } - t->mempools = dm_alloc_bio_mempools(t->integrity_supported, - per_bio_data_size); - break; - case DM_TYPE_REQUEST_BASED: - case DM_TYPE_MQ_REQUEST_BASED: - t->mempools = dm_alloc_rq_mempools(md, type); - break; - default: + if (unlikely(type == DM_TYPE_NONE)) { DMWARN("no table type is set, can't allocate mempools"); return -EINVAL; } + if (type == DM_TYPE_BIO_BASED) + for (i = 0; i < t->num_targets; i++) { + tgt = t->targets + i; + per_bio_data_size = max(per_bio_data_size, tgt->per_bio_data_size); + } + + t->mempools = dm_alloc_md_mempools(md, type, t->integrity_supported, per_bio_data_size); if (!t->mempools) return -ENOMEM; -- cgit v1.2.3