From patchwork Tue Nov 17 13:44:16 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Chandan Babu R X-Patchwork-Id: 11912253 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 778951391 for ; Tue, 17 Nov 2020 13:45:31 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 508E4206A5 for ; Tue, 17 Nov 2020 13:45:31 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="fZSpy1gX" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1732809AbgKQNpZ (ORCPT ); Tue, 17 Nov 2020 08:45:25 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:34870 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1732722AbgKQNpY (ORCPT ); Tue, 17 Nov 2020 08:45:24 -0500 Received: from mail-pg1-x52a.google.com (mail-pg1-x52a.google.com [IPv6:2607:f8b0:4864:20::52a]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id C27EEC0613CF for ; Tue, 17 Nov 2020 05:45:24 -0800 (PST) Received: by mail-pg1-x52a.google.com with SMTP id i13so16104533pgm.9 for ; Tue, 17 Nov 2020 05:45:24 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=from:to:cc:subject:date:message-id:in-reply-to:references :mime-version:content-transfer-encoding; bh=olhR5HB1EgorMwTXCqPaj+ypVe6b565JiLE0znLzIhI=; b=fZSpy1gXdjml8ew3wgojPlV9+WYpE+9FOfRgJ9h79iWyNzpVfQIyYMHYpJXcsy29UE HKvJDMqXzYgRLwLhfxFkc0L4eQDROxCCd5bXIh8YjMUXPcMj2CJYdI3sM3cw26IfFLHp 5A56FePnqWVkJzryBFWEy/emsLGUxUAE/zdgd6zVpPOMC49zZm19yoURmo7Zglf/1hFj W/GdkNIae69GdN1C/DTbdCut5BjYsjX8A7YLwWkixUNnPKLhgliyX4FEbAzVlwaeLyQU YednPKhpBVXlfT/xXrofp7pL3KES8voRmZWlfccLoXWhRYds5k3QjWlZ/lxIPgm/anZK CAZA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:date:message-id:in-reply-to :references:mime-version:content-transfer-encoding; bh=olhR5HB1EgorMwTXCqPaj+ypVe6b565JiLE0znLzIhI=; b=WpwrRtxj0SYzl2A1K8vuq1xvwIWOkJDFVb6bV6AyUM5akANWvWE1Y0bTWosZ+AsIV/ qtkYF2FZydXsq0VGDXyog2JkvmHOjpD1iXnwYcFvZFr1Qv0+iJCTAtHMAr29Tz27qCZX S6cPbGP69y8SiNanx+VOivhdwN4W7sEIj0yNjzhwDCrV0Ps+izTYoSxnTYcPRNFGNm+a rHZa83/lG+QptOD0F/R8oVQKmAJVmYOoJ5Qw/PbwmfwlttahJQ3uBiPv2rj4BKlYbJkt WiTwWH7/Wq/MuP2MFrpf24ozyeWLrRgX1v/Nk863MSp0v3szJca7caA61xRjSZi7HjV3 e6jg== X-Gm-Message-State: AOAM533OGsyhue5DmXjiYbF58xbQgsy4NEKCDSUaUwmw7CobU8heaFFJ ehtUXTCDLb0kcz5sAFnNkqQmenLRP14= X-Google-Smtp-Source: ABdhPJy4xaloClHI5vItRX3V5PVbUNCQzDDA3ngyzZfdbKSwWDXwZmbsNQ9dcLPDXqoGZ8G3L1T6ew== X-Received: by 2002:a62:64c1:0:b029:18a:d791:8162 with SMTP id y184-20020a6264c10000b029018ad7918162mr19151646pfb.24.1605620723837; Tue, 17 Nov 2020 05:45:23 -0800 (PST) Received: from localhost.localdomain ([122.179.49.210]) by smtp.gmail.com with ESMTPSA id y3sm3669399pjb.18.2020.11.17.05.45.21 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Tue, 17 Nov 2020 05:45:23 -0800 (PST) From: Chandan Babu R To: linux-xfs@vger.kernel.org Cc: Chandan Babu R , darrick.wong@oracle.com Subject: [PATCH V11 14/14] xfs: Introduce error injection to allocate only minlen size extents for files Date: Tue, 17 Nov 2020 19:14:16 +0530 Message-Id: <20201117134416.207945-15-chandanrlinux@gmail.com> X-Mailer: git-send-email 2.28.0 In-Reply-To: <20201117134416.207945-1-chandanrlinux@gmail.com> References: <20201117134416.207945-1-chandanrlinux@gmail.com> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-xfs@vger.kernel.org This commit adds XFS_ERRTAG_BMAP_ALLOC_MINLEN_EXTENT error tag which helps userspace test programs to get xfs_bmap_btalloc() to always allocate minlen sized extents. This is required for test programs which need a guarantee that minlen extents allocated for a file do not get merged with their existing neighbours in the inode's BMBT. "Inode fork extent overflow check" for Directories, Xattrs and extension of realtime inodes need this since the file offset at which the extents are being allocated cannot be explicitly controlled from userspace. One way to use this error tag is to, 1. Consume all of the free space by sequentially writing to a file. 2. Punch alternate blocks of the file. This causes CNTBT to contain sufficient number of one block sized extent records. 3. Inject XFS_ERRTAG_BMAP_ALLOC_MINLEN_EXTENT error tag. After step 3, xfs_bmap_btalloc() will issue space allocation requests for minlen sized extents only. ENOSPC error code is returned to userspace when there aren't any "one block sized" extents left in any of the AGs. Reviewed-by: Darrick J. Wong Signed-off-by: Chandan Babu R --- fs/xfs/libxfs/xfs_alloc.c | 50 ++++++++++++++ fs/xfs/libxfs/xfs_alloc.h | 3 + fs/xfs/libxfs/xfs_bmap.c | 124 ++++++++++++++++++++++++++++------- fs/xfs/libxfs/xfs_errortag.h | 4 +- fs/xfs/xfs_error.c | 3 + 5 files changed, 159 insertions(+), 25 deletions(-) diff --git a/fs/xfs/libxfs/xfs_alloc.c b/fs/xfs/libxfs/xfs_alloc.c index 852b536551b5..a7c4eb1d71d5 100644 --- a/fs/xfs/libxfs/xfs_alloc.c +++ b/fs/xfs/libxfs/xfs_alloc.c @@ -2473,6 +2473,47 @@ xfs_defer_agfl_block( xfs_defer_add(tp, XFS_DEFER_OPS_TYPE_AGFL_FREE, &new->xefi_list); } +#ifdef DEBUG +/* + * Check if an AGF has a free extent record whose length is equal to + * args->minlen. + */ +STATIC int +xfs_exact_minlen_extent_available( + struct xfs_alloc_arg *args, + struct xfs_buf *agbp, + int *stat) +{ + struct xfs_btree_cur *cnt_cur; + xfs_agblock_t fbno; + xfs_extlen_t flen; + int error = 0; + + cnt_cur = xfs_allocbt_init_cursor(args->mp, args->tp, agbp, + args->agno, XFS_BTNUM_CNT); + error = xfs_alloc_lookup_ge(cnt_cur, 0, args->minlen, stat); + if (error) + goto out; + + if (*stat == 0) { + error = -EFSCORRUPTED; + goto out; + } + + error = xfs_alloc_get_rec(cnt_cur, &fbno, &flen, stat); + if (error) + goto out; + + if (*stat == 1 && flen != args->minlen) + *stat = 0; + +out: + xfs_btree_del_cursor(cnt_cur, error); + + return error; +} +#endif + /* * Decide whether to use this allocation group for this allocation. * If so, fix up the btree freelist's size. @@ -2544,6 +2585,15 @@ xfs_alloc_fix_freelist( if (!xfs_alloc_space_available(args, need, flags)) goto out_agbp_relse; +#ifdef DEBUG + if (args->alloc_minlen_only) { + int stat; + + error = xfs_exact_minlen_extent_available(args, agbp, &stat); + if (error || !stat) + goto out_agbp_relse; + } +#endif /* * Make the freelist shorter if it's too long. * diff --git a/fs/xfs/libxfs/xfs_alloc.h b/fs/xfs/libxfs/xfs_alloc.h index 6c22b12176b8..a4427c5775c2 100644 --- a/fs/xfs/libxfs/xfs_alloc.h +++ b/fs/xfs/libxfs/xfs_alloc.h @@ -75,6 +75,9 @@ typedef struct xfs_alloc_arg { char wasfromfl; /* set if allocation is from freelist */ struct xfs_owner_info oinfo; /* owner of blocks being allocated */ enum xfs_ag_resv_type resv; /* block reservation to use */ +#ifdef DEBUG + bool alloc_minlen_only; /* allocate exact minlen extent */ +#endif } xfs_alloc_arg_t; /* diff --git a/fs/xfs/libxfs/xfs_bmap.c b/fs/xfs/libxfs/xfs_bmap.c index f6cd33684571..c57dcd3f46bc 100644 --- a/fs/xfs/libxfs/xfs_bmap.c +++ b/fs/xfs/libxfs/xfs_bmap.c @@ -3552,34 +3552,101 @@ xfs_bmap_process_allocated_extent( xfs_bmap_btalloc_accounting(ap, args); } -STATIC int -xfs_bmap_btalloc( - struct xfs_bmalloca *ap) /* bmap alloc argument struct */ +#ifdef DEBUG +static int +xfs_bmap_exact_minlen_extent_alloc( + struct xfs_bmalloca *ap) { - xfs_mount_t *mp; /* mount point structure */ - xfs_alloctype_t atype = 0; /* type for allocation routines */ - xfs_agnumber_t fb_agno; /* ag number of ap->firstblock */ - xfs_agnumber_t ag; - xfs_alloc_arg_t args; - xfs_fileoff_t orig_offset; - xfs_extlen_t orig_length; - xfs_extlen_t blen; - xfs_extlen_t nextminlen = 0; - int nullfb; /* true if ap->firstblock isn't set */ - int isaligned; - int tryagain; - int error; - int stripe_align; + struct xfs_mount *mp = ap->ip->i_mount; + struct xfs_alloc_arg args = { .tp = ap->tp, .mp = mp }; + xfs_fileoff_t orig_offset; + xfs_extlen_t orig_length; + int error; ASSERT(ap->length); + + if (ap->minlen != 1) { + ap->blkno = NULLFSBLOCK; + ap->length = 0; + return 0; + } + orig_offset = ap->offset; orig_length = ap->length; - mp = ap->ip->i_mount; + args.alloc_minlen_only = 1; - memset(&args, 0, sizeof(args)); - args.tp = ap->tp; - args.mp = mp; + xfs_bmap_compute_alignments(ap, &args); + + if (ap->tp->t_firstblock == NULLFSBLOCK) { + /* + * Unlike the longest extent available in an AG, we don't track + * the length of an AG's shortest extent. + * XFS_ERRTAG_BMAP_ALLOC_MINLEN_EXTENT is a debug only knob and + * hence we can afford to start traversing from the 0th AG since + * we need not be concerned about a drop in performance in + * "debug only" code paths. + */ + ap->blkno = XFS_AGB_TO_FSB(mp, 0, 0); + } else { + ap->blkno = ap->tp->t_firstblock; + } + + args.fsbno = ap->blkno; + args.oinfo = XFS_RMAP_OINFO_SKIP_UPDATE; + args.type = XFS_ALLOCTYPE_FIRST_AG; + args.total = args.minlen = args.maxlen = ap->minlen; + + args.alignment = 1; + args.minalignslop = 0; + + args.minleft = ap->minleft; + args.wasdel = ap->wasdel; + args.resv = XFS_AG_RESV_NONE; + args.datatype = ap->datatype; + + error = xfs_alloc_vextent(&args); + if (error) + return error; + + if (args.fsbno != NULLFSBLOCK) { + xfs_bmap_process_allocated_extent(ap, &args, orig_offset, + orig_length); + } else { + ap->blkno = NULLFSBLOCK; + ap->length = 0; + } + + return 0; +} +#else + +#define xfs_bmap_exact_minlen_extent_alloc(bma) (-EFSCORRUPTED) + +#endif + +STATIC int +xfs_bmap_btalloc( + struct xfs_bmalloca *ap) +{ + struct xfs_mount *mp = ap->ip->i_mount; + struct xfs_alloc_arg args = { .tp = ap->tp, .mp = mp }; + xfs_alloctype_t atype = 0; + xfs_agnumber_t fb_agno; /* ag number of ap->firstblock */ + xfs_agnumber_t ag; + xfs_fileoff_t orig_offset; + xfs_extlen_t orig_length; + xfs_extlen_t blen; + xfs_extlen_t nextminlen = 0; + int nullfb; /* true if ap->firstblock isn't set */ + int isaligned; + int tryagain; + int error; + int stripe_align; + + ASSERT(ap->length); + orig_offset = ap->offset; + orig_length = ap->length; stripe_align = xfs_bmap_compute_alignments(ap, &args); @@ -4113,6 +4180,10 @@ xfs_bmap_alloc_userdata( return xfs_bmap_rtalloc(bma); } + if (unlikely(XFS_TEST_ERROR(false, mp, + XFS_ERRTAG_BMAP_ALLOC_MINLEN_EXTENT))) + return xfs_bmap_exact_minlen_extent_alloc(bma); + return xfs_bmap_btalloc(bma); } @@ -4149,10 +4220,15 @@ xfs_bmapi_allocate( else bma->minlen = 1; - if (bma->flags & XFS_BMAPI_METADATA) - error = xfs_bmap_btalloc(bma); - else + if (bma->flags & XFS_BMAPI_METADATA) { + if (unlikely(XFS_TEST_ERROR(false, mp, + XFS_ERRTAG_BMAP_ALLOC_MINLEN_EXTENT))) + error = xfs_bmap_exact_minlen_extent_alloc(bma); + else + error = xfs_bmap_btalloc(bma); + } else { error = xfs_bmap_alloc_userdata(bma); + } if (error || bma->blkno == NULLFSBLOCK) return error; diff --git a/fs/xfs/libxfs/xfs_errortag.h b/fs/xfs/libxfs/xfs_errortag.h index 1c56fcceeea6..6ca9084b6934 100644 --- a/fs/xfs/libxfs/xfs_errortag.h +++ b/fs/xfs/libxfs/xfs_errortag.h @@ -57,7 +57,8 @@ #define XFS_ERRTAG_IUNLINK_FALLBACK 34 #define XFS_ERRTAG_BUF_IOERROR 35 #define XFS_ERRTAG_REDUCE_MAX_IEXTENTS 36 -#define XFS_ERRTAG_MAX 37 +#define XFS_ERRTAG_BMAP_ALLOC_MINLEN_EXTENT 37 +#define XFS_ERRTAG_MAX 38 /* * Random factors for above tags, 1 means always, 2 means 1/2 time, etc. @@ -99,5 +100,6 @@ #define XFS_RANDOM_IUNLINK_FALLBACK (XFS_RANDOM_DEFAULT/10) #define XFS_RANDOM_BUF_IOERROR XFS_RANDOM_DEFAULT #define XFS_RANDOM_REDUCE_MAX_IEXTENTS 1 +#define XFS_RANDOM_BMAP_ALLOC_MINLEN_EXTENT 1 #endif /* __XFS_ERRORTAG_H_ */ diff --git a/fs/xfs/xfs_error.c b/fs/xfs/xfs_error.c index 3780b118cc47..185b4915b7bf 100644 --- a/fs/xfs/xfs_error.c +++ b/fs/xfs/xfs_error.c @@ -55,6 +55,7 @@ static unsigned int xfs_errortag_random_default[] = { XFS_RANDOM_IUNLINK_FALLBACK, XFS_RANDOM_BUF_IOERROR, XFS_RANDOM_REDUCE_MAX_IEXTENTS, + XFS_RANDOM_BMAP_ALLOC_MINLEN_EXTENT, }; struct xfs_errortag_attr { @@ -166,6 +167,7 @@ XFS_ERRORTAG_ATTR_RW(bad_summary, XFS_ERRTAG_FORCE_SUMMARY_RECALC); XFS_ERRORTAG_ATTR_RW(iunlink_fallback, XFS_ERRTAG_IUNLINK_FALLBACK); XFS_ERRORTAG_ATTR_RW(buf_ioerror, XFS_ERRTAG_BUF_IOERROR); XFS_ERRORTAG_ATTR_RW(reduce_max_iextents, XFS_ERRTAG_REDUCE_MAX_IEXTENTS); +XFS_ERRORTAG_ATTR_RW(bmap_alloc_minlen_extent, XFS_ERRTAG_BMAP_ALLOC_MINLEN_EXTENT); static struct attribute *xfs_errortag_attrs[] = { XFS_ERRORTAG_ATTR_LIST(noerror), @@ -205,6 +207,7 @@ static struct attribute *xfs_errortag_attrs[] = { XFS_ERRORTAG_ATTR_LIST(iunlink_fallback), XFS_ERRORTAG_ATTR_LIST(buf_ioerror), XFS_ERRORTAG_ATTR_LIST(reduce_max_iextents), + XFS_ERRORTAG_ATTR_LIST(bmap_alloc_minlen_extent), NULL, };