From patchwork Thu Oct 14 20:17:22 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "Darrick J. Wong" X-Patchwork-Id: 12559365 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 mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 17839C433F5 for ; Thu, 14 Oct 2021 20:17:24 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id F3F5A61019 for ; Thu, 14 Oct 2021 20:17:23 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230494AbhJNUT2 (ORCPT ); Thu, 14 Oct 2021 16:19:28 -0400 Received: from mail.kernel.org ([198.145.29.99]:35064 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229587AbhJNUT2 (ORCPT ); Thu, 14 Oct 2021 16:19:28 -0400 Received: by mail.kernel.org (Postfix) with ESMTPSA id C354661027; Thu, 14 Oct 2021 20:17:22 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1634242642; bh=NJBOqEgduRbYcHTL6jNX3Tx05FEzBJTMRjpbH+6Nx60=; h=Subject:From:To:Cc:Date:In-Reply-To:References:From; b=scdjg2MHu3W8gaGSJWUbgx781O2nF0uymsRLO2Q00sJi7s+LONZid7lz29zbifTFq YvJkBlKet0qcjeOb1w0UBezAxfzXVOJQ//i9TXblahdMdTRl9vp08Y9W9FeNGyZYCZ 0v4Di5SMlTcbaqAqKEFr0gw3AUCSQpnvc18iZpUp9oxnWg3r9HdhGa1uSRf1u4kGm6 suFqLg6VVWmw6HLxKS/uh+vuHQXxR0eugjxnDmXLYg68F42QKItY5WQ1DMKrsblmKU xWNiPkMnflpmL68Wau2Fm1TW57UIW7l9mPWd+nuKvpQc42KIm668HsfRvhsis2nUx/ sdHF/gOJmD1Hw== Subject: [PATCH 05/17] xfs: dynamically allocate btree scrub context structure From: "Darrick J. Wong" To: djwong@kernel.org, david@fromorbit.com Cc: linux-xfs@vger.kernel.org, chandan.babu@oracle.com, hch@lst.de Date: Thu, 14 Oct 2021 13:17:22 -0700 Message-ID: <163424264249.756780.1871555838190156050.stgit@magnolia> In-Reply-To: <163424261462.756780.16294781570977242370.stgit@magnolia> References: <163424261462.756780.16294781570977242370.stgit@magnolia> User-Agent: StGit/0.19 MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-xfs@vger.kernel.org From: Darrick J. Wong Reorganize struct xchk_btree so that we can dynamically size the context structure to fit the type of btree cursor that we have. This will enable us to use memory more efficiently once we start adding very tall btree types. Right-size the lastkey array to match the number of *node* levels in the tree so that we stop wasting space. Signed-off-by: Darrick J. Wong Reviewed-by: Dave Chinner --- fs/xfs/scrub/btree.c | 23 ++++++++++++----------- fs/xfs/scrub/btree.h | 15 ++++++++++++++- 2 files changed, 26 insertions(+), 12 deletions(-) diff --git a/fs/xfs/scrub/btree.c b/fs/xfs/scrub/btree.c index d5e1ca521fc4..6d4eba85ef77 100644 --- a/fs/xfs/scrub/btree.c +++ b/fs/xfs/scrub/btree.c @@ -189,9 +189,9 @@ xchk_btree_key( /* If this isn't the first key, are they in order? */ if (cur->bc_ptrs[level] > 1 && - !cur->bc_ops->keys_inorder(cur, &bs->lastkey[level], key)) + !cur->bc_ops->keys_inorder(cur, &bs->lastkey[level - 1], key)) xchk_btree_set_corrupt(bs->sc, cur, level); - memcpy(&bs->lastkey[level], key, cur->bc_ops->key_len); + memcpy(&bs->lastkey[level - 1], key, cur->bc_ops->key_len); if (level + 1 >= cur->bc_nlevels) return; @@ -631,17 +631,24 @@ xchk_btree( union xfs_btree_ptr *pp; union xfs_btree_rec *recp; struct xfs_btree_block *block; - int level; struct xfs_buf *bp; struct check_owner *co; struct check_owner *n; + size_t cur_sz; + int level; int error = 0; /* * Allocate the btree scrub context from the heap, because this - * structure can get rather large. + * structure can get rather large. Don't let a caller feed us a + * totally absurd size. */ - bs = kmem_zalloc(sizeof(struct xchk_btree), KM_NOFS | KM_MAYFAIL); + cur_sz = xchk_btree_sizeof(cur->bc_nlevels); + if (cur_sz > PAGE_SIZE) { + xchk_btree_set_corrupt(sc, cur, 0); + return 0; + } + bs = kmem_zalloc(cur_sz, KM_NOFS | KM_MAYFAIL); if (!bs) return -ENOMEM; bs->cur = cur; @@ -653,12 +660,6 @@ xchk_btree( /* Initialize scrub state */ INIT_LIST_HEAD(&bs->to_check); - /* Don't try to check a tree with a height we can't handle. */ - if (cur->bc_nlevels > XFS_BTREE_MAXLEVELS) { - xchk_btree_set_corrupt(sc, cur, 0); - goto out; - } - /* * Load the root of the btree. The helper function absorbs * error codes for us. diff --git a/fs/xfs/scrub/btree.h b/fs/xfs/scrub/btree.h index 7671108f9f85..da61a53a0b61 100644 --- a/fs/xfs/scrub/btree.h +++ b/fs/xfs/scrub/btree.h @@ -39,9 +39,22 @@ struct xchk_btree { /* internal scrub state */ union xfs_btree_rec lastrec; - union xfs_btree_key lastkey[XFS_BTREE_MAXLEVELS]; struct list_head to_check; + + /* this element must come last! */ + union xfs_btree_key lastkey[]; }; + +/* + * Calculate the size of a xchk_btree structure. There are nlevels-1 slots for + * keys because we track leaf records separately in lastrec. + */ +static inline size_t +xchk_btree_sizeof(unsigned int nlevels) +{ + return struct_size((struct xchk_btree *)NULL, lastkey, nlevels - 1); +} + int xchk_btree(struct xfs_scrub *sc, struct xfs_btree_cur *cur, xchk_btree_rec_fn scrub_fn, const struct xfs_owner_info *oinfo, void *private);