From patchwork Thu Jan 23 08:18:46 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Johannes Thumshirn X-Patchwork-Id: 11346977 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 AFA84139A for ; Thu, 23 Jan 2020 08:19:01 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 843AC24683 for ; Thu, 23 Jan 2020 08:19:01 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (2048-bit key) header.d=wdc.com header.i=@wdc.com header.b="NrnWlSp9" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728057AbgAWITA (ORCPT ); Thu, 23 Jan 2020 03:19:00 -0500 Received: from esa6.hgst.iphmx.com ([216.71.154.45]:43990 "EHLO esa6.hgst.iphmx.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726234AbgAWIS7 (ORCPT ); Thu, 23 Jan 2020 03:18:59 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=simple/simple; d=wdc.com; i=@wdc.com; q=dns/txt; s=dkim.wdc.com; t=1579767539; x=1611303539; h=from:to:cc:subject:date:message-id:in-reply-to: references:mime-version:content-transfer-encoding; bh=19XjfNb2DsyFkWApWGJ7z72fug2kMoPozXI2kQJWYVU=; b=NrnWlSp9Ktued/Lf3C0bwSzk2xokZXHtIKrj/Uhv0rgyBeoU9loWGKB0 2SP0mgkcJIIu3CdmdYEyGlcno2IMj6GyOSdD6p5GB/iDxsm3ofu3Y2Tc7 9Up37HrVfQDwnReLFPx6YmZEpkXtzgKXRZaPsmU2xgj9Decg0mjw5TkKe zoVlzVq9nCWZgD2cCFFgqg9ixLK5vfWJ7KjiVFYVQ66mV0fRa2im4TC86 WB5oANBh/4niu/P8d7eqw6ECojfSh+mj5WBLEecZjsFlAtYwcn5W7KY+p Vnd6dOHyKi28m6cP8YiykmID0T8zBgwxMfzpkX9eV6VW9DEmAJOheukUt A==; IronPort-SDR: y7/fzD7DHYpSSifDoOWeuD/BOk89OmEv+Gmv/uI+C3nW14BLBdsAQ55b+G5vEyAzRPOox/Vfz4 QJ7vLfDSM7Qi5is8luHLwYU+PTqUAsM3ZjRGvPbVVZwBqoyres8pTPwAboLrgZkPMoIaE3q/5w XmFxK7qDlbkkYTBOfXqMhWryGZ97LgLiB1lpwQKPD5EtMc22P6rJosBKQGNvDmGokX8byt7f8Z qkPSLfG7CEjOqFtcd004vQNF2P9zRtfTz/niS4yM/8CWScziHG6aKvMleKbrPohTY9NzVmh0AN KLs= X-IronPort-AV: E=Sophos;i="5.70,353,1574092800"; d="scan'208";a="129708690" Received: from h199-255-45-14.hgst.com (HELO uls-op-cesaep01.wdc.com) ([199.255.45.14]) by ob1.hgst.iphmx.com with ESMTP; 23 Jan 2020 16:18:59 +0800 IronPort-SDR: EJlXZITaj0KfUTnctTE93YVL10oZ6qnAkJVQwd2KbA6pK94J6mNWL6L7gQNQ2id1TOSNMCz/nz n/O5Noc6jrB+sydLKdX4a9uiYtRr3V3Ink8UoFlkBLqzvVshI3xXELAUtbxzFei5Q41pKvBZV8 Vi1Ln1j54ZJZy7TutIFZD6U5Trh4V99sAB4jHH1HQlE4jNOJ8HG1aFHJxtmG6GW4jcXijrliCP TG4fg3jTZR1o48xvdhRxancN/3q7SqpWKjSzOHq1YrLW0La5QYCEoDbVjdnPufaztwMZT7BYnL g49JvlFJVC4D/FoaIYV61Z2T Received: from uls-op-cesaip02.wdc.com ([10.248.3.37]) by uls-op-cesaep01.wdc.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 23 Jan 2020 00:12:21 -0800 IronPort-SDR: pNqSPTVbHJUTIGJW/nJLDOEfSSNe0LLoHWPK9y5GEGNtfLOdDmDnr8M/sbqSYVaN345qHFi+tM Vb8oUT1prW+0UQBCVWZ0JExBwY49Wi59z9ROyDs4GRapnRjh+Qdja1/P/xi5T++/y9BMDQHcy3 /18YetMq63X+tpqCLvOV0GgclV+y1ainGGYnx3sPHc9ymg1wY3/kmwNpLZ+CqCKtwS5QC5x948 1NC/tFT+iwbntFnFCdwDLfU1g2AgZBAGy9cf0ppUF1v3nBNfNDqHOBbgsyG7upGgOy1DAhcZRy enA= WDCIronportException: Internal Received: from unknown (HELO redsun60.ssa.fujisawa.hgst.com) ([10.149.66.36]) by uls-op-cesaip02.wdc.com with ESMTP; 23 Jan 2020 00:18:58 -0800 From: Johannes Thumshirn To: David Sterba Cc: Nikolay Borisov , "linux-btrfs @ vger . kernel . org" , Johannes Thumshirn Subject: [PATCH v2 3/6] btrfs: remove use of buffer_heads from superblock writeout Date: Thu, 23 Jan 2020 17:18:46 +0900 Message-Id: <20200123081849.23397-4-johannes.thumshirn@wdc.com> X-Mailer: git-send-email 2.24.1 In-Reply-To: <20200123081849.23397-1-johannes.thumshirn@wdc.com> References: <20200123081849.23397-1-johannes.thumshirn@wdc.com> MIME-Version: 1.0 Sender: linux-btrfs-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-btrfs@vger.kernel.org Similar to the superblock read path, change the write path to using BIOs and pages instead of buffer_heads. This allows us to skip over the buffer_head code, for writing the superblock to disk. This is based on a patch originally authored by Nikolay Borisov. Co-developed-by: Nikolay Borisov Signed-off-by: Johannes Thumshirn Reviewed-by: Josef Bacik Signed-off-by: Nikolay Borisov Reviewed-by: Nikolay Borisov --- Changes to v1: - Remove left-over buffer_head.h include (David) --- fs/btrfs/disk-io.c | 111 ++++++++++++++++++++++++++------------------- 1 file changed, 64 insertions(+), 47 deletions(-) diff --git a/fs/btrfs/disk-io.c b/fs/btrfs/disk-io.c index b111f32108cc..ac1755793596 100644 --- a/fs/btrfs/disk-io.c +++ b/fs/btrfs/disk-io.c @@ -7,7 +7,6 @@ #include #include #include -#include #include #include #include @@ -3356,25 +3355,33 @@ int __cold open_ctree(struct super_block *sb, } ALLOW_ERROR_INJECTION(open_ctree, ERRNO); -static void btrfs_end_buffer_write_sync(struct buffer_head *bh, int uptodate) +static void btrfs_end_super_write(struct bio *bio) { - if (uptodate) { - set_buffer_uptodate(bh); - } else { - struct btrfs_device *device = (struct btrfs_device *) - bh->b_private; - - btrfs_warn_rl_in_rcu(device->fs_info, - "lost page write due to IO error on %s", - rcu_str_deref(device->name)); - /* note, we don't set_buffer_write_io_error because we have - * our own ways of dealing with the IO errors - */ - clear_buffer_uptodate(bh); - btrfs_dev_stat_inc_and_print(device, BTRFS_DEV_STAT_WRITE_ERRS); + struct btrfs_device *device = bio->bi_private; + struct bio_vec *bvec; + struct bvec_iter_all iter_all; + struct page *page; + + bio_for_each_segment_all(bvec, bio, iter_all) { + page = bvec->bv_page; + + if (blk_status_to_errno(bio->bi_status)) { + btrfs_warn_rl_in_rcu(device->fs_info, + "lost page write due to IO error on %s", + rcu_str_deref(device->name)); + ClearPageUptodate(page); + SetPageError(page); + btrfs_dev_stat_inc_and_print(device, + BTRFS_DEV_STAT_WRITE_ERRS); + } else { + SetPageUptodate(page); + } + + put_page(page); + unlock_page(page); } - unlock_buffer(bh); - put_bh(bh); + + bio_put(bio); } int btrfs_read_dev_one_super(struct block_device *bdev, int copy_num, @@ -3475,16 +3482,16 @@ int btrfs_read_dev_super(struct block_device *bdev, struct page **page) * the expected device size at commit time. Note that max_mirrors must be * same for write and wait phases. * - * Return number of errors when buffer head is not found or submission fails. + * Return number of errors when page is not found or submission fails. */ static int write_dev_supers(struct btrfs_device *device, struct btrfs_super_block *sb, int max_mirrors) { struct btrfs_fs_info *fs_info = device->fs_info; + struct address_space *mapping = device->bdev->bd_inode->i_mapping; SHASH_DESC_ON_STACK(shash, fs_info->csum_shash); - struct buffer_head *bh; + gfp_t gfp_mask; int i; - int ret; int errors = 0; u64 bytenr; int op_flags; @@ -3494,7 +3501,13 @@ static int write_dev_supers(struct btrfs_device *device, shash->tfm = fs_info->csum_shash; + gfp_mask = mapping_gfp_constraint(mapping, ~__GFP_FS) | __GFP_NOFAIL; + for (i = 0; i < max_mirrors; i++) { + struct page *page; + struct bio *bio; + u8 *ptr; + bytenr = btrfs_sb_offset(i); if (bytenr + BTRFS_SUPER_INFO_SIZE >= device->commit_total_bytes) @@ -3507,26 +3520,22 @@ static int write_dev_supers(struct btrfs_device *device, BTRFS_SUPER_INFO_SIZE - BTRFS_CSUM_SIZE); crypto_shash_final(shash, sb->csum); - /* One reference for us, and we leave it for the caller */ - bh = __getblk(device->bdev, bytenr / BTRFS_BDEV_BLOCKSIZE, - BTRFS_SUPER_INFO_SIZE); - if (!bh) { + page = find_or_create_page(mapping, bytenr >> PAGE_SHIFT, + gfp_mask); + if (!page) { btrfs_err(device->fs_info, - "couldn't get super buffer head for bytenr %llu", + "couldn't get superblock page for bytenr %llu", bytenr); errors++; continue; } - memcpy(bh->b_data, sb, BTRFS_SUPER_INFO_SIZE); - - /* one reference for submit_bh */ - get_bh(bh); + /* Bump the refcount for wait_dev_supers() */ + get_page(page); - set_buffer_uptodate(bh); - lock_buffer(bh); - bh->b_end_io = btrfs_end_buffer_write_sync; - bh->b_private = device; + ptr = kmap(page); + memcpy(ptr, sb, BTRFS_SUPER_INFO_SIZE); + kunmap(page); /* * we fua the first super. The others we allow @@ -3535,9 +3544,17 @@ static int write_dev_supers(struct btrfs_device *device, op_flags = REQ_SYNC | REQ_META | REQ_PRIO; if (i == 0 && !btrfs_test_opt(device->fs_info, NOBARRIER)) op_flags |= REQ_FUA; - ret = btrfsic_submit_bh(REQ_OP_WRITE, op_flags, bh); - if (ret) - errors++; + + bio = bio_alloc(gfp_mask, 1); + bio_set_dev(bio, device->bdev); + bio->bi_iter.bi_sector = bytenr >> SECTOR_SHIFT; + bio->bi_private = device; + bio->bi_end_io = btrfs_end_super_write; + bio_add_page(bio, page, BTRFS_SUPER_INFO_SIZE, + offset_in_page(bytenr)); + + bio_set_op_attrs(bio, REQ_OP_WRITE, op_flags); + btrfsic_submit_bio(bio); } return errors < i ? 0 : -1; } @@ -3546,12 +3563,11 @@ static int write_dev_supers(struct btrfs_device *device, * Wait for write completion of superblocks done by write_dev_supers, * @max_mirrors same for write and wait phases. * - * Return number of errors when buffer head is not found or not marked up to + * Return number of errors when page is not found or not marked up to * date. */ static int wait_dev_supers(struct btrfs_device *device, int max_mirrors) { - struct buffer_head *bh; int i; int errors = 0; bool primary_failed = false; @@ -3561,32 +3577,33 @@ static int wait_dev_supers(struct btrfs_device *device, int max_mirrors) max_mirrors = BTRFS_SUPER_MIRROR_MAX; for (i = 0; i < max_mirrors; i++) { + struct page *page; + bytenr = btrfs_sb_offset(i); if (bytenr + BTRFS_SUPER_INFO_SIZE >= device->commit_total_bytes) break; - bh = __find_get_block(device->bdev, - bytenr / BTRFS_BDEV_BLOCKSIZE, - BTRFS_SUPER_INFO_SIZE); - if (!bh) { + page = find_get_page(device->bdev->bd_inode->i_mapping, + bytenr >> PAGE_SHIFT); + if (!page) { errors++; if (i == 0) primary_failed = true; continue; } - wait_on_buffer(bh); - if (!buffer_uptodate(bh)) { + wait_on_page_locked(page); + if (PageError(page)) { errors++; if (i == 0) primary_failed = true; } /* drop our reference */ - brelse(bh); + put_page(page); /* drop the reference from the writing run */ - brelse(bh); + put_page(page); } /* log error, force error return */