From: Mikulas Patocka <mpatocka@xxxxxxxxxx> 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 <mpatocka@xxxxxxxxxx> Signed-off-by: Mike Snitzer <snitzer@xxxxxxxxxx> --- 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 -- dm-devel mailing list dm-devel@xxxxxxxxxx https://www.redhat.com/mailman/listinfo/dm-devel
