Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932818AbaDBSEU (ORCPT ); Wed, 2 Apr 2014 14:04:20 -0400 Received: from mx1.redhat.com ([209.132.183.28]:34508 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932332AbaDBSET (ORCPT ); Wed, 2 Apr 2014 14:04:19 -0400 From: Mike Snitzer To: axboe@fb.com Cc: linux-kernel@vger.kernel.org, mpatocka@redhat.com, dm-devel@redhat.com Subject: [PATCH] block: use kmalloc alignment for bio slab Date: Wed, 2 Apr 2014 14:04:16 -0400 Message-Id: <1396461856-27243-1-git-send-email-snitzer@redhat.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Mikulas Patocka Various subsystems can ask the bio subsystem to create a bio slab cache with some free space before the bio. This free space can be used for any purpose. Device mapper uses this per-bio-data feature to place some target-specific and device-mapper specific data before the bio, so that the target-specific data doesn't have to be allocated separately. This per-bio-data mechanism is used in place of kmalloc, so we need the allocated slab to have the same memory alignment as memory allocated with kmalloc. Change bio_find_or_create_slab() so that it uses ARCH_KMALLOC_MINALIGN alignment when creating the slab cache. This is needed so that dm-crypt can use per-bio-data for encryption - the crypto subsystem assumes this data will have the same alignment as kmalloc'ed memory. Signed-off-by: Mikulas Patocka Signed-off-by: Mike Snitzer --- fs/bio.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/fs/bio.c b/fs/bio.c index b2dd42e..6c94ba6 100644 --- a/fs/bio.c +++ b/fs/bio.c @@ -112,7 +112,8 @@ static struct kmem_cache *bio_find_or_create_slab(unsigned int extra_size) bslab = &bio_slabs[entry]; snprintf(bslab->name, sizeof(bslab->name), "bio-%d", entry); - slab = kmem_cache_create(bslab->name, sz, 0, SLAB_HWCACHE_ALIGN, NULL); + slab = kmem_cache_create(bslab->name, sz, ARCH_KMALLOC_MINALIGN, + SLAB_HWCACHE_ALIGN, NULL); if (!slab) goto out_unlock; -- 1.8.1.4 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/