From patchwork Thu Nov 17 05:58:09 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Dave Chinner X-Patchwork-Id: 13046174 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 37937C4321E for ; Thu, 17 Nov 2022 05:58:33 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S239313AbiKQF6c (ORCPT ); Thu, 17 Nov 2022 00:58:32 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:50172 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S239257AbiKQF6T (ORCPT ); Thu, 17 Nov 2022 00:58:19 -0500 Received: from mail-pj1-x1032.google.com (mail-pj1-x1032.google.com [IPv6:2607:f8b0:4864:20::1032]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 6EA486712D for ; Wed, 16 Nov 2022 21:58:17 -0800 (PST) Received: by mail-pj1-x1032.google.com with SMTP id h14so740865pjv.4 for ; Wed, 16 Nov 2022 21:58:17 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=fromorbit-com.20210112.gappssmtp.com; s=20210112; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:from:to:cc:subject:date :message-id:reply-to; bh=yPsvTS2BI2IeXfVqfQ6H3wTeT3xMq3QJNEv8pCZIwxs=; b=dm5IZtJ6aWASthefILjJwaBZNYzkQg+LxYIg6r32IYbXw48QH9XXAqSVozqrDTqXmJ 9VPopdSkw+kdVzJI/+sHi4HygNskgr8PFijaG/qNfed+s6eD4P8OBBaz1fSd0dAaKDH6 peyCOJhQgykqJou6747Qvjva5ns97rkWFgihlcMX8iTJc91E89M9TVQ1MbXGwUy8sM8z jbwhIdLAR1cohAYLtME6hq+qnOGSyVrpqzk+VfeKp2iPeY9YZGs2E594IFhNisrOn8tY xx7rtEwU/QfPou/UCsNE66epmMNE0CMaTpGBmscFxHrElNLUV6g0DiJwHWhz+1s6OHRx wIqA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:x-gm-message-state:from:to:cc :subject:date:message-id:reply-to; bh=yPsvTS2BI2IeXfVqfQ6H3wTeT3xMq3QJNEv8pCZIwxs=; b=ECAMAaXgQvT29AGfm4CicCM+0qxY7/x4lClMmXL5CXtBda8azyitN6ZYHGGL/hw0iG sk46S6+vjKqAIJxKISUE954pXI9HNp84aDVbszK/E9sMOLivIlVHyDUtMF0Y4m7EGFor VYCqlAESFam2kpQxPENfOoxd/jDTTo7EYlErv8LvObcZe7C3BeUzV7ylIx5ibuL2tn/2 +ErMA0v/WqW43VhkITWP0ptfzugFeuJL9Yq6joCSLQkqVxCL8w0cQVl/fbPL2X4lmC5w vukxbil+kml7PEVpGt1mnvXOUfHcNZj4qDzNiOXrHbDNdvTQFRyzRsy9ZDvP3vEoNuq5 +6Ug== X-Gm-Message-State: ANoB5pnKY3aXqE5VFy0bHia8ZWF1heM2mVs4BOW+4zNlkQAzJHTvPOno nL9jBF0NJMek8KhhHuvWHzGoZg== X-Google-Smtp-Source: AA0mqf4b+qXd1PKQSKcgcvhuu0k87PcVdojP8LgnmThWzx0L1wGSoJ15DPQUytOn2p44R5a6JnBWlQ== X-Received: by 2002:a17:90a:ac07:b0:20a:f75d:b9af with SMTP id o7-20020a17090aac0700b0020af75db9afmr7029670pjq.222.1668664696853; Wed, 16 Nov 2022 21:58:16 -0800 (PST) Received: from dread.disaster.area (pa49-181-106-210.pa.nsw.optusnet.com.au. [49.181.106.210]) by smtp.gmail.com with ESMTPSA id h19-20020a656393000000b0044ed37dbca8sm205318pgv.2.2022.11.16.21.58.14 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Wed, 16 Nov 2022 21:58:15 -0800 (PST) Received: from discord.disaster.area ([192.168.253.110]) by dread.disaster.area with esmtp (Exim 4.92.3) (envelope-from ) id 1ovXue-00FBpY-E9; Thu, 17 Nov 2022 16:58:12 +1100 Received: from dave by discord.disaster.area with local (Exim 4.96) (envelope-from ) id 1ovXue-0025cm-1G; Thu, 17 Nov 2022 16:58:12 +1100 From: Dave Chinner To: linux-xfs@vger.kernel.org Cc: linux-fsdevel@vger.kernel.org Subject: [PATCH 8/9] xfs: use iomap_valid method to detect stale cached iomaps Date: Thu, 17 Nov 2022 16:58:09 +1100 Message-Id: <20221117055810.498014-9-david@fromorbit.com> X-Mailer: git-send-email 2.37.2 In-Reply-To: <20221117055810.498014-1-david@fromorbit.com> References: <20221117055810.498014-1-david@fromorbit.com> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-fsdevel@vger.kernel.org From: Dave Chinner Now that iomap supports a mechanism to validate cached iomaps for buffered write operations, hook it up to the XFS buffered write ops so that we can avoid data corruptions that result from stale cached iomaps. See: https://lore.kernel.org/linux-xfs/20220817093627.GZ3600936@dread.disaster.area/ or the ->iomap_valid() introduction commit for exact details of the corruption vector. The validity cookie we store in the iomap is based on the type of iomap we return. It is expected that the iomap->flags we set in xfs_bmbt_to_iomap() is not perturbed by the iomap core and are returned to us in the iomap passed via the .iomap_valid() callback. This ensures that the validity cookie is always checking the correct inode fork sequence numbers to detect potential changes that affect the extent cached by the iomap. Signed-off-by: Dave Chinner Reviewed-by: Darrick J. Wong --- fs/xfs/libxfs/xfs_bmap.c | 6 ++- fs/xfs/xfs_aops.c | 2 +- fs/xfs/xfs_iomap.c | 96 +++++++++++++++++++++++++++++++--------- fs/xfs/xfs_iomap.h | 5 ++- fs/xfs/xfs_pnfs.c | 6 ++- 5 files changed, 88 insertions(+), 27 deletions(-) diff --git a/fs/xfs/libxfs/xfs_bmap.c b/fs/xfs/libxfs/xfs_bmap.c index 49d0d4ea63fc..56b9b7db38bb 100644 --- a/fs/xfs/libxfs/xfs_bmap.c +++ b/fs/xfs/libxfs/xfs_bmap.c @@ -4551,7 +4551,8 @@ xfs_bmapi_convert_delalloc( * the extent. Just return the real extent at this offset. */ if (!isnullstartblock(bma.got.br_startblock)) { - xfs_bmbt_to_iomap(ip, iomap, &bma.got, 0, flags); + xfs_bmbt_to_iomap(ip, iomap, &bma.got, 0, flags, + xfs_iomap_inode_sequence(ip, flags)); *seq = READ_ONCE(ifp->if_seq); goto out_trans_cancel; } @@ -4599,7 +4600,8 @@ xfs_bmapi_convert_delalloc( XFS_STATS_INC(mp, xs_xstrat_quick); ASSERT(!isnullstartblock(bma.got.br_startblock)); - xfs_bmbt_to_iomap(ip, iomap, &bma.got, 0, flags); + xfs_bmbt_to_iomap(ip, iomap, &bma.got, 0, flags, + xfs_iomap_inode_sequence(ip, flags)); *seq = READ_ONCE(ifp->if_seq); if (whichfork == XFS_COW_FORK) diff --git a/fs/xfs/xfs_aops.c b/fs/xfs/xfs_aops.c index 6aadc5815068..a22d90af40c8 100644 --- a/fs/xfs/xfs_aops.c +++ b/fs/xfs/xfs_aops.c @@ -372,7 +372,7 @@ xfs_map_blocks( isnullstartblock(imap.br_startblock)) goto allocate_blocks; - xfs_bmbt_to_iomap(ip, &wpc->iomap, &imap, 0, 0); + xfs_bmbt_to_iomap(ip, &wpc->iomap, &imap, 0, 0, XFS_WPC(wpc)->data_seq); trace_xfs_map_blocks_found(ip, offset, count, whichfork, &imap); return 0; allocate_blocks: diff --git a/fs/xfs/xfs_iomap.c b/fs/xfs/xfs_iomap.c index 09676ff6940e..a9b3a1bcc3fd 100644 --- a/fs/xfs/xfs_iomap.c +++ b/fs/xfs/xfs_iomap.c @@ -48,13 +48,45 @@ xfs_alert_fsblock_zero( return -EFSCORRUPTED; } +u64 +xfs_iomap_inode_sequence( + struct xfs_inode *ip, + u16 iomap_flags) +{ + u64 cookie = 0; + + if (iomap_flags & IOMAP_F_XATTR) + return READ_ONCE(ip->i_af.if_seq); + if ((iomap_flags & IOMAP_F_SHARED) && ip->i_cowfp) + cookie = (u64)READ_ONCE(ip->i_cowfp->if_seq) << 32; + return cookie | READ_ONCE(ip->i_df.if_seq); +} + +/* + * Check that the iomap passed to us is still valid for the given offset and + * length. + */ +static bool +xfs_iomap_valid( + struct inode *inode, + const struct iomap *iomap) +{ + return iomap->validity_cookie == + xfs_iomap_inode_sequence(XFS_I(inode), iomap->flags); +} + +const struct iomap_page_ops xfs_iomap_page_ops = { + .iomap_valid = xfs_iomap_valid, +}; + int xfs_bmbt_to_iomap( struct xfs_inode *ip, struct iomap *iomap, struct xfs_bmbt_irec *imap, unsigned int mapping_flags, - u16 iomap_flags) + u16 iomap_flags, + u64 sequence_cookie) { struct xfs_mount *mp = ip->i_mount; struct xfs_buftarg *target = xfs_inode_buftarg(ip); @@ -91,6 +123,9 @@ xfs_bmbt_to_iomap( if (xfs_ipincount(ip) && (ip->i_itemp->ili_fsync_fields & ~XFS_ILOG_TIMESTAMP)) iomap->flags |= IOMAP_F_DIRTY; + + iomap->validity_cookie = sequence_cookie; + iomap->page_ops = &xfs_iomap_page_ops; return 0; } @@ -195,7 +230,8 @@ xfs_iomap_write_direct( xfs_fileoff_t offset_fsb, xfs_fileoff_t count_fsb, unsigned int flags, - struct xfs_bmbt_irec *imap) + struct xfs_bmbt_irec *imap, + u64 *seq) { struct xfs_mount *mp = ip->i_mount; struct xfs_trans *tp; @@ -285,6 +321,8 @@ xfs_iomap_write_direct( error = xfs_alert_fsblock_zero(ip, imap); out_unlock: + if (seq) + *seq = xfs_iomap_inode_sequence(ip, 0); xfs_iunlock(ip, XFS_ILOCK_EXCL); return error; @@ -743,6 +781,7 @@ xfs_direct_write_iomap_begin( bool shared = false; u16 iomap_flags = 0; unsigned int lockmode = XFS_ILOCK_SHARED; + u64 seq; ASSERT(flags & (IOMAP_WRITE | IOMAP_ZERO)); @@ -811,9 +850,10 @@ xfs_direct_write_iomap_begin( goto out_unlock; } + seq = xfs_iomap_inode_sequence(ip, iomap_flags); xfs_iunlock(ip, lockmode); trace_xfs_iomap_found(ip, offset, length, XFS_DATA_FORK, &imap); - return xfs_bmbt_to_iomap(ip, iomap, &imap, flags, iomap_flags); + return xfs_bmbt_to_iomap(ip, iomap, &imap, flags, iomap_flags, seq); allocate_blocks: error = -EAGAIN; @@ -839,24 +879,26 @@ xfs_direct_write_iomap_begin( xfs_iunlock(ip, lockmode); error = xfs_iomap_write_direct(ip, offset_fsb, end_fsb - offset_fsb, - flags, &imap); + flags, &imap, &seq); if (error) return error; trace_xfs_iomap_alloc(ip, offset, length, XFS_DATA_FORK, &imap); return xfs_bmbt_to_iomap(ip, iomap, &imap, flags, - iomap_flags | IOMAP_F_NEW); + iomap_flags | IOMAP_F_NEW, seq); out_found_cow: - xfs_iunlock(ip, lockmode); length = XFS_FSB_TO_B(mp, cmap.br_startoff + cmap.br_blockcount); trace_xfs_iomap_found(ip, offset, length - offset, XFS_COW_FORK, &cmap); if (imap.br_startblock != HOLESTARTBLOCK) { - error = xfs_bmbt_to_iomap(ip, srcmap, &imap, flags, 0); + seq = xfs_iomap_inode_sequence(ip, 0); + error = xfs_bmbt_to_iomap(ip, srcmap, &imap, flags, 0, seq); if (error) - return error; + goto out_unlock; } - return xfs_bmbt_to_iomap(ip, iomap, &cmap, flags, IOMAP_F_SHARED); + seq = xfs_iomap_inode_sequence(ip, IOMAP_F_SHARED); + xfs_iunlock(ip, lockmode); + return xfs_bmbt_to_iomap(ip, iomap, &cmap, flags, IOMAP_F_SHARED, seq); out_unlock: if (lockmode) @@ -915,6 +957,7 @@ xfs_buffered_write_iomap_begin( int allocfork = XFS_DATA_FORK; int error = 0; unsigned int lockmode = XFS_ILOCK_EXCL; + u64 seq; if (xfs_is_shutdown(mp)) return -EIO; @@ -1094,26 +1137,31 @@ xfs_buffered_write_iomap_begin( * Flag newly allocated delalloc blocks with IOMAP_F_NEW so we punch * them out if the write happens to fail. */ + seq = xfs_iomap_inode_sequence(ip, IOMAP_F_NEW); xfs_iunlock(ip, XFS_ILOCK_EXCL); trace_xfs_iomap_alloc(ip, offset, count, allocfork, &imap); - return xfs_bmbt_to_iomap(ip, iomap, &imap, flags, IOMAP_F_NEW); + return xfs_bmbt_to_iomap(ip, iomap, &imap, flags, IOMAP_F_NEW, seq); found_imap: + seq = xfs_iomap_inode_sequence(ip, 0); xfs_iunlock(ip, XFS_ILOCK_EXCL); - return xfs_bmbt_to_iomap(ip, iomap, &imap, flags, 0); + return xfs_bmbt_to_iomap(ip, iomap, &imap, flags, 0, seq); found_cow: - xfs_iunlock(ip, XFS_ILOCK_EXCL); + seq = xfs_iomap_inode_sequence(ip, 0); if (imap.br_startoff <= offset_fsb) { - error = xfs_bmbt_to_iomap(ip, srcmap, &imap, flags, 0); + error = xfs_bmbt_to_iomap(ip, srcmap, &imap, flags, 0, seq); if (error) - return error; + goto out_unlock; + seq = xfs_iomap_inode_sequence(ip, IOMAP_F_SHARED); + xfs_iunlock(ip, XFS_ILOCK_EXCL); return xfs_bmbt_to_iomap(ip, iomap, &cmap, flags, - IOMAP_F_SHARED); + IOMAP_F_SHARED, seq); } xfs_trim_extent(&cmap, offset_fsb, imap.br_startoff - offset_fsb); - return xfs_bmbt_to_iomap(ip, iomap, &cmap, flags, 0); + xfs_iunlock(ip, XFS_ILOCK_EXCL); + return xfs_bmbt_to_iomap(ip, iomap, &cmap, flags, 0, seq); out_unlock: xfs_iunlock(ip, XFS_ILOCK_EXCL); @@ -1193,6 +1241,7 @@ xfs_read_iomap_begin( int nimaps = 1, error = 0; bool shared = false; unsigned int lockmode = XFS_ILOCK_SHARED; + u64 seq; ASSERT(!(flags & (IOMAP_WRITE | IOMAP_ZERO))); @@ -1206,13 +1255,14 @@ xfs_read_iomap_begin( &nimaps, 0); if (!error && (flags & IOMAP_REPORT)) error = xfs_reflink_trim_around_shared(ip, &imap, &shared); + seq = xfs_iomap_inode_sequence(ip, shared ? IOMAP_F_SHARED : 0); xfs_iunlock(ip, lockmode); if (error) return error; trace_xfs_iomap_found(ip, offset, length, XFS_DATA_FORK, &imap); return xfs_bmbt_to_iomap(ip, iomap, &imap, flags, - shared ? IOMAP_F_SHARED : 0); + shared ? IOMAP_F_SHARED : 0, seq); } const struct iomap_ops xfs_read_iomap_ops = { @@ -1237,6 +1287,7 @@ xfs_seek_iomap_begin( struct xfs_bmbt_irec imap, cmap; int error = 0; unsigned lockmode; + u64 seq; if (xfs_is_shutdown(mp)) return -EIO; @@ -1271,8 +1322,9 @@ xfs_seek_iomap_begin( if (data_fsb < cow_fsb + cmap.br_blockcount) end_fsb = min(end_fsb, data_fsb); xfs_trim_extent(&cmap, offset_fsb, end_fsb); + seq = xfs_iomap_inode_sequence(ip, IOMAP_F_SHARED); error = xfs_bmbt_to_iomap(ip, iomap, &cmap, flags, - IOMAP_F_SHARED); + IOMAP_F_SHARED, seq); /* * This is a COW extent, so we must probe the page cache * because there could be dirty page cache being backed @@ -1293,8 +1345,9 @@ xfs_seek_iomap_begin( imap.br_startblock = HOLESTARTBLOCK; imap.br_state = XFS_EXT_NORM; done: + seq = xfs_iomap_inode_sequence(ip, 0); xfs_trim_extent(&imap, offset_fsb, end_fsb); - error = xfs_bmbt_to_iomap(ip, iomap, &imap, flags, 0); + error = xfs_bmbt_to_iomap(ip, iomap, &imap, flags, 0, seq); out_unlock: xfs_iunlock(ip, lockmode); return error; @@ -1320,6 +1373,7 @@ xfs_xattr_iomap_begin( struct xfs_bmbt_irec imap; int nimaps = 1, error = 0; unsigned lockmode; + int seq; if (xfs_is_shutdown(mp)) return -EIO; @@ -1336,12 +1390,14 @@ xfs_xattr_iomap_begin( error = xfs_bmapi_read(ip, offset_fsb, end_fsb - offset_fsb, &imap, &nimaps, XFS_BMAPI_ATTRFORK); out_unlock: + + seq = xfs_iomap_inode_sequence(ip, IOMAP_F_XATTR); xfs_iunlock(ip, lockmode); if (error) return error; ASSERT(nimaps); - return xfs_bmbt_to_iomap(ip, iomap, &imap, flags, 0); + return xfs_bmbt_to_iomap(ip, iomap, &imap, flags, IOMAP_F_XATTR, seq); } const struct iomap_ops xfs_xattr_iomap_ops = { diff --git a/fs/xfs/xfs_iomap.h b/fs/xfs/xfs_iomap.h index 0f62ab633040..4da13440bae9 100644 --- a/fs/xfs/xfs_iomap.h +++ b/fs/xfs/xfs_iomap.h @@ -13,14 +13,15 @@ struct xfs_bmbt_irec; int xfs_iomap_write_direct(struct xfs_inode *ip, xfs_fileoff_t offset_fsb, xfs_fileoff_t count_fsb, unsigned int flags, - struct xfs_bmbt_irec *imap); + struct xfs_bmbt_irec *imap, u64 *sequence); int xfs_iomap_write_unwritten(struct xfs_inode *, xfs_off_t, xfs_off_t, bool); xfs_fileoff_t xfs_iomap_eof_align_last_fsb(struct xfs_inode *ip, xfs_fileoff_t end_fsb); +u64 xfs_iomap_inode_sequence(struct xfs_inode *ip, u16 iomap_flags); int xfs_bmbt_to_iomap(struct xfs_inode *ip, struct iomap *iomap, struct xfs_bmbt_irec *imap, unsigned int mapping_flags, - u16 iomap_flags); + u16 iomap_flags, u64 sequence_cookie); int xfs_zero_range(struct xfs_inode *ip, loff_t pos, loff_t len, bool *did_zero); diff --git a/fs/xfs/xfs_pnfs.c b/fs/xfs/xfs_pnfs.c index 37a24f0f7cd4..38d23f0e703a 100644 --- a/fs/xfs/xfs_pnfs.c +++ b/fs/xfs/xfs_pnfs.c @@ -125,6 +125,7 @@ xfs_fs_map_blocks( int nimaps = 1; uint lock_flags; int error = 0; + u64 seq; if (xfs_is_shutdown(mp)) return -EIO; @@ -176,6 +177,7 @@ xfs_fs_map_blocks( lock_flags = xfs_ilock_data_map_shared(ip); error = xfs_bmapi_read(ip, offset_fsb, end_fsb - offset_fsb, &imap, &nimaps, bmapi_flags); + seq = xfs_iomap_inode_sequence(ip, 0); ASSERT(!nimaps || imap.br_startblock != DELAYSTARTBLOCK); @@ -189,7 +191,7 @@ xfs_fs_map_blocks( xfs_iunlock(ip, lock_flags); error = xfs_iomap_write_direct(ip, offset_fsb, - end_fsb - offset_fsb, 0, &imap); + end_fsb - offset_fsb, 0, &imap, &seq); if (error) goto out_unlock; @@ -209,7 +211,7 @@ xfs_fs_map_blocks( } xfs_iunlock(ip, XFS_IOLOCK_EXCL); - error = xfs_bmbt_to_iomap(ip, iomap, &imap, 0, 0); + error = xfs_bmbt_to_iomap(ip, iomap, &imap, 0, 0, seq); *device_generation = mp->m_generation; return error; out_unlock: