Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1757928AbcKCOEo (ORCPT ); Thu, 3 Nov 2016 10:04:44 -0400 Received: from mx2.suse.de ([195.135.220.15]:56601 "EHLO mx2.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752152AbcKCOES (ORCPT ); Thu, 3 Nov 2016 10:04:18 -0400 From: Hannes Reinecke To: Jens Axboe Cc: Christoph Hellwig , Alexander Graf , Ming Lei , Martin Schwidefsky , linux-kernel@vger.kernel.org, Hannes Reinecke , Hannes Reinecke Subject: [PATCH 2/2] loop: support 4k physical blocksize Date: Thu, 3 Nov 2016 15:04:06 +0100 Message-Id: <1478181846-88863-3-git-send-email-hare@suse.de> X-Mailer: git-send-email 1.8.5.6 In-Reply-To: <1478181846-88863-1-git-send-email-hare@suse.de> References: <1478181846-88863-1-git-send-email-hare@suse.de> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 4891 Lines: 136 When generating bootable VM images certain systems (most notably s390x) require devices with 4k blocksize. This patch implements a new flag 'LO_FLAGS_BLOCKSIZE' which will set the physical blocksize to that of the underlying device, and allow to change the logical blocksize for up to the physical blocksize. Signed-off-by: Hannes Reinecke --- drivers/block/loop.c | 36 +++++++++++++++++++++++++++++++----- drivers/block/loop.h | 1 + include/uapi/linux/loop.h | 1 + 3 files changed, 33 insertions(+), 5 deletions(-) diff --git a/drivers/block/loop.c b/drivers/block/loop.c index 3008dec..9ad56bf 100644 --- a/drivers/block/loop.c +++ b/drivers/block/loop.c @@ -221,7 +221,8 @@ static void __loop_update_dio(struct loop_device *lo, bool dio) } static int -figure_loop_size(struct loop_device *lo, loff_t offset, loff_t sizelimit) +figure_loop_size(struct loop_device *lo, loff_t offset, loff_t sizelimit, + loff_t logical_blocksize) { loff_t size = get_size(offset, sizelimit, lo->lo_backing_file); sector_t x = (sector_t)size; @@ -233,6 +234,12 @@ figure_loop_size(struct loop_device *lo, loff_t offset, loff_t sizelimit) lo->lo_offset = offset; if (lo->lo_sizelimit != sizelimit) lo->lo_sizelimit = sizelimit; + if (lo->lo_flags & LO_FLAGS_BLOCKSIZE) { + lo->lo_logical_blocksize = logical_blocksize; + blk_queue_physical_block_size(lo->lo_queue, lo->lo_blocksize); + blk_queue_logical_block_size(lo->lo_queue, + lo->lo_logical_blocksize); + } set_capacity(lo->lo_disk, x); bd_set_size(bdev, (loff_t)get_capacity(bdev->bd_disk) << 9); /* let user-space know about the new size */ @@ -814,6 +821,7 @@ static void loop_config_discard(struct loop_device *lo) struct file *file = lo->lo_backing_file; struct inode *inode = file->f_mapping->host; struct request_queue *q = lo->lo_queue; + int lo_bits = blksize_bits(lo->lo_logical_blocksize); /* * We use punch hole to reclaim the free space used by the @@ -833,7 +841,7 @@ static void loop_config_discard(struct loop_device *lo) q->limits.discard_granularity = inode->i_sb->s_blocksize; q->limits.discard_alignment = 0; - blk_queue_max_discard_sectors(q, UINT_MAX >> 9); + blk_queue_max_discard_sectors(q, UINT_MAX >> lo_bits); q->limits.discard_zeroes_data = 1; queue_flag_set_unlocked(QUEUE_FLAG_DISCARD, q); } @@ -922,6 +930,7 @@ static int loop_set_fd(struct loop_device *lo, fmode_t mode, lo->use_dio = false; lo->lo_blocksize = lo_blocksize; + lo->lo_logical_blocksize = 512; lo->lo_device = bdev; lo->lo_flags = lo_flags; lo->lo_backing_file = file; @@ -1087,6 +1096,7 @@ loop_set_status(struct loop_device *lo, const struct loop_info64 *info) int err; struct loop_func_table *xfer; kuid_t uid = current_uid(); + int lo_flags = lo->lo_flags; if (lo->lo_encrypt_key_size && !uid_eq(lo->lo_key_owner, uid) && @@ -1116,9 +1126,24 @@ loop_set_status(struct loop_device *lo, const struct loop_info64 *info) if (err) return err; + if (info->lo_flags & LO_FLAGS_BLOCKSIZE) { + lo->lo_flags |= LO_FLAGS_BLOCKSIZE; + if ((info->lo_init[0] != 512) && + (info->lo_init[0] != 1024) && + (info->lo_init[0] != 2048) && + (info->lo_init[0] != 4096)) + return -EINVAL; + if (info->lo_init[0] > lo->lo_blocksize) + return -EINVAL; + } + if (lo->lo_offset != info->lo_offset || - lo->lo_sizelimit != info->lo_sizelimit) - if (figure_loop_size(lo, info->lo_offset, info->lo_sizelimit)) + lo->lo_sizelimit != info->lo_sizelimit || + lo->lo_flags != lo_flags || + ((lo->lo_flags & LO_FLAGS_BLOCKSIZE) && + (lo->lo_logical_blocksize != info->lo_init[0]))) + if (figure_loop_size(lo, info->lo_offset, info->lo_sizelimit, + info->lo_init[0])) return -EFBIG; loop_config_discard(lo); @@ -1303,7 +1328,8 @@ static int loop_set_capacity(struct loop_device *lo) if (unlikely(lo->lo_state != Lo_bound)) return -ENXIO; - return figure_loop_size(lo, lo->lo_offset, lo->lo_sizelimit); + return figure_loop_size(lo, lo->lo_offset, lo->lo_sizelimit, + lo->lo_logical_blocksize); } static int loop_set_dio(struct loop_device *lo, unsigned long arg) diff --git a/drivers/block/loop.h b/drivers/block/loop.h index fb2237c..579f2f7 100644 --- a/drivers/block/loop.h +++ b/drivers/block/loop.h @@ -49,6 +49,7 @@ struct loop_device { struct file * lo_backing_file; struct block_device *lo_device; unsigned lo_blocksize; + unsigned lo_logical_blocksize; void *key_data; gfp_t old_gfp_mask; diff --git a/include/uapi/linux/loop.h b/include/uapi/linux/loop.h index c8125ec..2691c1c 100644 --- a/include/uapi/linux/loop.h +++ b/include/uapi/linux/loop.h @@ -22,6 +22,7 @@ enum { LO_FLAGS_AUTOCLEAR = 4, LO_FLAGS_PARTSCAN = 8, LO_FLAGS_DIRECT_IO = 16, + LO_FLAGS_BLOCKSIZE = 32, }; #include /* for __kernel_old_dev_t */ -- 2.6.6