From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-18.7 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER, INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED, USER_AGENT_GIT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id EAB12C433DB for ; Thu, 4 Feb 2021 07:04:37 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id A227B64E4D for ; Thu, 4 Feb 2021 07:04:37 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S233603AbhBDHEU (ORCPT ); Thu, 4 Feb 2021 02:04:20 -0500 Received: from mx2.suse.de ([195.135.220.15]:56518 "EHLO mx2.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232633AbhBDHET (ORCPT ); Thu, 4 Feb 2021 02:04:19 -0500 X-Virus-Scanned: by amavisd-new at test-mx.suse.de DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=suse.com; s=susede1; t=1612422211; h=from:from:reply-to:date:date:message-id:message-id:to:to:cc: mime-version:mime-version: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=i7iMl/fAhJbD+PIEVRHr/dR3JxNP2eRyC68Eahd4Wtw=; b=XbV88BtL96Z8XNCGNqcBSk/1/Hjps1JMPu6F01jfV74drq5gj3I+otWVHdFNjk15GPbIaj HJ59OszAam48io6OajmzEvxLc0GVP1kOW1xh7/fIvRHkrk5HfvgF0MgARriLqmJ2ZtTxHW /FbI+bBgc2M71kB0aAsRic0WTjP6nvw= Received: from relay2.suse.de (unknown [195.135.221.27]) by mx2.suse.de (Postfix) with ESMTP id B3620ACF4 for ; Thu, 4 Feb 2021 07:03:31 +0000 (UTC) From: Qu Wenruo To: linux-btrfs@vger.kernel.org Subject: [PATCH 2/2] btrfs: make check_compressed_csum() to be subpage compatible Date: Thu, 4 Feb 2021 15:03:24 +0800 Message-Id: <20210204070324.45703-3-wqu@suse.com> X-Mailer: git-send-email 2.30.0 In-Reply-To: <20210204070324.45703-1-wqu@suse.com> References: <20210204070324.45703-1-wqu@suse.com> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-btrfs@vger.kernel.org Currently check_compressed_csum() completely relies on sectorsize == PAGE_SIZE to do checksum verification for compressed extents. To make it subpage compatible, this patch will: - Do extra calculation for the csum range Since we have multiple sectors inside a page, we need to only hash the range we want, not the full page anymore. - Do sector-by-sector hash inside the page With this patch and previous conversion on btrfs_submit_compressed_read(), now we can read subpage compressed extents properly, and do proper csum verification. Signed-off-by: Qu Wenruo --- fs/btrfs/compression.c | 41 ++++++++++++++++++++++++++++------------- 1 file changed, 28 insertions(+), 13 deletions(-) diff --git a/fs/btrfs/compression.c b/fs/btrfs/compression.c index 3d16ca5d420d..696459d9d244 100644 --- a/fs/btrfs/compression.c +++ b/fs/btrfs/compression.c @@ -141,6 +141,7 @@ static int check_compressed_csum(struct btrfs_inode *inode, struct bio *bio, struct btrfs_fs_info *fs_info = inode->root->fs_info; SHASH_DESC_ON_STACK(shash, fs_info->csum_shash); const u32 csum_size = fs_info->csum_size; + const u32 sectorsize = fs_info->sectorsize; struct page *page; unsigned long i; char *kaddr; @@ -154,22 +155,36 @@ static int check_compressed_csum(struct btrfs_inode *inode, struct bio *bio, shash->tfm = fs_info->csum_shash; for (i = 0; i < cb->nr_pages; i++) { + u32 pg_offset; + u32 bytes_left; page = cb->compressed_pages[i]; - kaddr = kmap_atomic(page); - crypto_shash_digest(shash, kaddr, PAGE_SIZE, csum); - kunmap_atomic(kaddr); - - if (memcmp(&csum, cb_sum, csum_size)) { - btrfs_print_data_csum_error(inode, disk_start, - csum, cb_sum, cb->mirror_num); - if (btrfs_io_bio(bio)->device) - btrfs_dev_stat_inc_and_print( - btrfs_io_bio(bio)->device, - BTRFS_DEV_STAT_CORRUPTION_ERRS); - return -EIO; + /* Determine the remaining bytes inside the page first */ + if (i == cb->nr_pages - 1) + bytes_left = cb->compressed_len - i * PAGE_SIZE; + else + bytes_left = PAGE_SIZE; + + /* Hash through the page sector by sector */ + for (pg_offset = 0; pg_offset < bytes_left; + pg_offset += sectorsize) { + kaddr = kmap_atomic(page); + crypto_shash_digest(shash, kaddr + pg_offset, + sectorsize, csum); + kunmap_atomic(kaddr); + + if (memcmp(&csum, cb_sum, csum_size)) { + btrfs_print_data_csum_error(inode, disk_start, + csum, cb_sum, cb->mirror_num); + if (btrfs_io_bio(bio)->device) + btrfs_dev_stat_inc_and_print( + btrfs_io_bio(bio)->device, + BTRFS_DEV_STAT_CORRUPTION_ERRS); + return -EIO; + } + cb_sum += csum_size; + disk_start += sectorsize; } - cb_sum += csum_size; } return 0; } -- 2.30.0