From patchwork Wed Jan 22 10:58:13 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Kirill Tkhai X-Patchwork-Id: 11345541 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 714376C1 for ; Wed, 22 Jan 2020 10:58:45 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 503472467B for ; Wed, 22 Jan 2020 10:58:45 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729447AbgAVK6o (ORCPT ); Wed, 22 Jan 2020 05:58:44 -0500 Received: from relay.sw.ru ([185.231.240.75]:49992 "EHLO relay.sw.ru" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728890AbgAVK6b (ORCPT ); Wed, 22 Jan 2020 05:58:31 -0500 Received: from dhcp-172-16-24-104.sw.ru ([172.16.24.104] helo=localhost.localdomain) by relay.sw.ru with esmtp (Exim 4.92.3) (envelope-from ) id 1iuDiA-0002gg-9L; Wed, 22 Jan 2020 13:58:14 +0300 Subject: [PATCH v5 4/6] block: Add support for REQ_ALLOCATE flag From: Kirill Tkhai To: linux-block@vger.kernel.org, linux-kernel@vger.kernel.org, martin.petersen@oracle.com, bob.liu@oracle.com, axboe@kernel.dk, agk@redhat.com, snitzer@redhat.com, dm-devel@redhat.com, song@kernel.org, tytso@mit.edu, adilger.kernel@dilger.ca, Chaitanya.Kulkarni@wdc.com, darrick.wong@oracle.com, ming.lei@redhat.com, osandov@fb.com, jthumshirn@suse.de, minwoo.im.dev@gmail.com, damien.lemoal@wdc.com, andrea.parri@amarulasolutions.com, hare@suse.com, tj@kernel.org, ajay.joshi@wdc.com, sagi@grimberg.me, dsterba@suse.com, chaitanya.kulkarni@wdc.com, bvanassche@acm.org, dhowells@redhat.com, asml.silence@gmail.com, ktkhai@virtuozzo.com Date: Wed, 22 Jan 2020 13:58:13 +0300 Message-ID: <157969069360.174869.18184061012552778480.stgit@localhost.localdomain> In-Reply-To: <157968992539.174869.7490844754165043549.stgit@localhost.localdomain> References: <157968992539.174869.7490844754165043549.stgit@localhost.localdomain> User-Agent: StGit/0.19 MIME-Version: 1.0 Sender: linux-block-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-block@vger.kernel.org This adds support for REQ_ALLOCATE extension of REQ_OP_WRITE_ZEROES operation, which encourages a block device driver to just allocate blocks (or mark them allocated) instead of actual blocks zeroing. REQ_ALLOCATE is aimed to be used for network filesystems providing a block device interface. Also, block devices, which map a file on other filesystem (like loop), may use this for less fragmentation and batching fallocate() requests. Hypervisors like QEMU may introduce optimizations of clusters allocations based on this. BLKDEV_ZERO_ALLOCATE is a new corresponding flag for blkdev_issue_zeroout(). Stacking devices start from zero max_allocate_sectors limit for now, and the support is going to be implemented separate for each device in the future. Signed-off-by: Kirill Tkhai Reviewed-by: Bob Liu --- block/blk-lib.c | 17 ++++++++++------- block/blk-settings.c | 4 ++++ fs/block_dev.c | 4 ++++ include/linux/blk_types.h | 5 ++++- include/linux/blkdev.h | 13 ++++++++++--- 5 files changed, 32 insertions(+), 11 deletions(-) diff --git a/block/blk-lib.c b/block/blk-lib.c index 3e38c93cfc53..9cd6f86523ba 100644 --- a/block/blk-lib.c +++ b/block/blk-lib.c @@ -214,7 +214,7 @@ static int __blkdev_issue_write_zeroes(struct block_device *bdev, struct bio **biop, unsigned flags) { struct bio *bio = *biop; - unsigned int max_write_zeroes_sectors; + unsigned int max_write_zeroes_sectors, req_flags = 0; struct request_queue *q = bdev_get_queue(bdev); if (!q) @@ -224,18 +224,21 @@ static int __blkdev_issue_write_zeroes(struct block_device *bdev, return -EPERM; /* Ensure that max_write_zeroes_sectors doesn't overflow bi_size */ - max_write_zeroes_sectors = bdev_write_zeroes_sectors(bdev, 0); + max_write_zeroes_sectors = bdev_write_zeroes_sectors(bdev, flags); if (max_write_zeroes_sectors == 0) return -EOPNOTSUPP; + if (flags & BLKDEV_ZERO_NOUNMAP) + req_flags |= REQ_NOUNMAP; + if (flags & BLKDEV_ZERO_ALLOCATE) + req_flags |= REQ_ALLOCATE|REQ_NOUNMAP; + while (nr_sects) { bio = blk_next_bio(bio, 0, gfp_mask); bio->bi_iter.bi_sector = sector; bio_set_dev(bio, bdev); - bio->bi_opf = REQ_OP_WRITE_ZEROES; - if (flags & BLKDEV_ZERO_NOUNMAP) - bio->bi_opf |= REQ_NOUNMAP; + bio->bi_opf = REQ_OP_WRITE_ZEROES | req_flags; if (nr_sects > max_write_zeroes_sectors) { bio->bi_iter.bi_size = max_write_zeroes_sectors << 9; @@ -362,7 +365,7 @@ int blkdev_issue_zeroout(struct block_device *bdev, sector_t sector, sector_t bs_mask; struct bio *bio; struct blk_plug plug; - bool try_write_zeroes = !!bdev_write_zeroes_sectors(bdev, 0); + bool try_write_zeroes = !!bdev_write_zeroes_sectors(bdev, flags); bs_mask = (bdev_logical_block_size(bdev) >> 9) - 1; if ((sector | nr_sects) & bs_mask) @@ -391,7 +394,7 @@ int blkdev_issue_zeroout(struct block_device *bdev, sector_t sector, try_write_zeroes = false; goto retry; } - if (!bdev_write_zeroes_sectors(bdev, 0)) { + if (!bdev_write_zeroes_sectors(bdev, flags)) { /* * Zeroing offload support was indicated, but the * device reported ILLEGAL REQUEST (for some devices diff --git a/block/blk-settings.c b/block/blk-settings.c index c8eda2e7b91e..8d5df9d37239 100644 --- a/block/blk-settings.c +++ b/block/blk-settings.c @@ -48,6 +48,7 @@ void blk_set_default_limits(struct queue_limits *lim) lim->chunk_sectors = 0; lim->max_write_same_sectors = 0; lim->max_write_zeroes_sectors = 0; + lim->max_allocate_sectors = 0; lim->max_discard_sectors = 0; lim->max_hw_discard_sectors = 0; lim->discard_granularity = 0; @@ -83,6 +84,7 @@ void blk_set_stacking_limits(struct queue_limits *lim) lim->max_dev_sectors = UINT_MAX; lim->max_write_same_sectors = UINT_MAX; lim->max_write_zeroes_sectors = UINT_MAX; + lim->max_allocate_sectors = 0; } EXPORT_SYMBOL(blk_set_stacking_limits); @@ -506,6 +508,8 @@ int blk_stack_limits(struct queue_limits *t, struct queue_limits *b, b->max_write_same_sectors); t->max_write_zeroes_sectors = min(t->max_write_zeroes_sectors, b->max_write_zeroes_sectors); + t->max_allocate_sectors = min(t->max_allocate_sectors, + b->max_allocate_sectors); t->bounce_pfn = min_not_zero(t->bounce_pfn, b->bounce_pfn); t->seg_boundary_mask = min_not_zero(t->seg_boundary_mask, diff --git a/fs/block_dev.c b/fs/block_dev.c index 69bf2fb6f7cd..1ffef894b3bd 100644 --- a/fs/block_dev.c +++ b/fs/block_dev.c @@ -2122,6 +2122,10 @@ static long blkdev_fallocate(struct file *file, int mode, loff_t start, error = blkdev_issue_zeroout(bdev, start >> 9, len >> 9, GFP_KERNEL, BLKDEV_ZERO_NOFALLBACK); break; + case FALLOC_FL_KEEP_SIZE: + error = blkdev_issue_zeroout(bdev, start >> 9, len >> 9, + GFP_KERNEL, BLKDEV_ZERO_ALLOCATE | BLKDEV_ZERO_NOFALLBACK); + break; case FALLOC_FL_PUNCH_HOLE | FALLOC_FL_KEEP_SIZE | FALLOC_FL_NO_HIDE_STALE: error = blkdev_issue_discard(bdev, start >> 9, len >> 9, GFP_KERNEL, 0); diff --git a/include/linux/blk_types.h b/include/linux/blk_types.h index 70254ae11769..86accd2caa4e 100644 --- a/include/linux/blk_types.h +++ b/include/linux/blk_types.h @@ -335,7 +335,9 @@ enum req_flag_bits { /* command specific flags for REQ_OP_WRITE_ZEROES: */ __REQ_NOUNMAP, /* do not free blocks when zeroing */ - + __REQ_ALLOCATE, /* only notify about allocated blocks, + * and do not actually zero them + */ __REQ_HIPRI, /* for driver use */ @@ -362,6 +364,7 @@ enum req_flag_bits { #define REQ_CGROUP_PUNT (1ULL << __REQ_CGROUP_PUNT) #define REQ_NOUNMAP (1ULL << __REQ_NOUNMAP) +#define REQ_ALLOCATE (1ULL << __REQ_ALLOCATE) #define REQ_HIPRI (1ULL << __REQ_HIPRI) #define REQ_DRV (1ULL << __REQ_DRV) diff --git a/include/linux/blkdev.h b/include/linux/blkdev.h index 264202fa3bf8..20c94a7f9411 100644 --- a/include/linux/blkdev.h +++ b/include/linux/blkdev.h @@ -337,6 +337,7 @@ struct queue_limits { unsigned int max_hw_discard_sectors; unsigned int max_write_same_sectors; unsigned int max_write_zeroes_sectors; + unsigned int max_allocate_sectors; unsigned int discard_granularity; unsigned int discard_alignment; @@ -991,6 +992,8 @@ static inline struct bio_vec req_bvec(struct request *rq) static inline unsigned int blk_queue_get_max_write_zeroes_sectors( struct request_queue *q, unsigned int op_flags) { + if (op_flags & REQ_ALLOCATE) + return q->limits.max_allocate_sectors; return q->limits.max_write_zeroes_sectors; } @@ -1227,6 +1230,7 @@ extern int __blkdev_issue_discard(struct block_device *bdev, sector_t sector, #define BLKDEV_ZERO_NOUNMAP (1 << 0) /* do not free blocks */ #define BLKDEV_ZERO_NOFALLBACK (1 << 1) /* don't write explicit zeroes */ +#define BLKDEV_ZERO_ALLOCATE (1 << 2) /* allocate range of blocks */ extern int __blkdev_issue_zeroout(struct block_device *bdev, sector_t sector, sector_t nr_sects, gfp_t gfp_mask, struct bio **biop, @@ -1431,10 +1435,13 @@ static inline unsigned int bdev_write_zeroes_sectors(struct block_device *bdev, { struct request_queue *q = bdev_get_queue(bdev); - if (q) - return q->limits.max_write_zeroes_sectors; + if (!q) + return 0; - return 0; + if (flags & BLKDEV_ZERO_ALLOCATE) + return q->limits.max_allocate_sectors; + else + return q->limits.max_write_zeroes_sectors; } static inline enum blk_zoned_model bdev_zoned_model(struct block_device *bdev)