From patchwork Thu Oct 14 17:58:59 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Brian Foster X-Patchwork-Id: 12559173 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 39AABC433F5 for ; Thu, 14 Oct 2021 17:59:08 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 10615610F8 for ; Thu, 14 Oct 2021 17:59:08 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231784AbhJNSBM (ORCPT ); Thu, 14 Oct 2021 14:01:12 -0400 Received: from us-smtp-delivery-124.mimecast.com ([170.10.133.124]:44957 "EHLO us-smtp-delivery-124.mimecast.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229718AbhJNSBL (ORCPT ); Thu, 14 Oct 2021 14:01:11 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1634234346; h=from:from:reply-to:subject:subject: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=899n4Cs37JwtsuQzeruFYH7jYnBaCfdtMTUMKUpg4Ds=; b=chaYQqwthvkTwJCaM+Az9wzw1vbBK8buJQiJCQW7VOKknI2ZQFexDZ4wFxJwWOpiGup8UL Pcl/WeC9YQe4HXGNuAdt6/kDvMo08Qx6itT6LRJgHoF3ELayr6j189oRLwWF9Z7WMv3hUU Xr84whvg58fxgBNecOymsOOUauugAw4= Received: from mimecast-mx01.redhat.com (mimecast-mx01.redhat.com [209.132.183.4]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-596-pMePES2wNH6E8L5A_HBT4A-1; Thu, 14 Oct 2021 13:59:04 -0400 X-MC-Unique: pMePES2wNH6E8L5A_HBT4A-1 Received: from smtp.corp.redhat.com (int-mx06.intmail.prod.int.phx2.redhat.com [10.5.11.16]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id 2B1B410B3956 for ; Thu, 14 Oct 2021 17:59:04 +0000 (UTC) Received: from bfoster.redhat.com (unknown [10.22.8.90]) by smtp.corp.redhat.com (Postfix) with ESMTP id DD77C5C1A3 for ; Thu, 14 Oct 2021 17:59:03 +0000 (UTC) From: Brian Foster To: linux-xfs@vger.kernel.org Subject: [PATCH v3 1/4] xfs: fold perag loop iteration logic into helper function Date: Thu, 14 Oct 2021 13:58:59 -0400 Message-Id: <20211014175902.1519172-2-bfoster@redhat.com> In-Reply-To: <20211014175902.1519172-1-bfoster@redhat.com> References: <20211014175902.1519172-1-bfoster@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.79 on 10.5.11.16 Precedence: bulk List-ID: X-Mailing-List: linux-xfs@vger.kernel.org Fold the loop iteration logic into a helper in preparation for further fixups. No functional change in this patch. Signed-off-by: Brian Foster Reviewed-by: Dave Chinner Reviewed-by: Darrick J. Wong --- fs/xfs/libxfs/xfs_ag.h | 16 +++++++++++++--- 1 file changed, 13 insertions(+), 3 deletions(-) diff --git a/fs/xfs/libxfs/xfs_ag.h b/fs/xfs/libxfs/xfs_ag.h index 4c6f9045baca..ddb89e10b6ea 100644 --- a/fs/xfs/libxfs/xfs_ag.h +++ b/fs/xfs/libxfs/xfs_ag.h @@ -124,12 +124,22 @@ void xfs_perag_put(struct xfs_perag *pag); * for_each_perag_from() because they terminate at sb_agcount where there are * no perag structures in tree beyond end_agno. */ +static inline struct xfs_perag * +xfs_perag_next( + struct xfs_perag *pag, + xfs_agnumber_t *next_agno) +{ + struct xfs_mount *mp = pag->pag_mount; + + *next_agno = pag->pag_agno + 1; + xfs_perag_put(pag); + return xfs_perag_get(mp, *next_agno); +} + #define for_each_perag_range(mp, next_agno, end_agno, pag) \ for ((pag) = xfs_perag_get((mp), (next_agno)); \ (pag) != NULL && (next_agno) <= (end_agno); \ - (next_agno) = (pag)->pag_agno + 1, \ - xfs_perag_put(pag), \ - (pag) = xfs_perag_get((mp), (next_agno))) + (pag) = xfs_perag_next((pag), &(next_agno))) #define for_each_perag_from(mp, next_agno, pag) \ for_each_perag_range((mp), (next_agno), (mp)->m_sb.sb_agcount, (pag)) From patchwork Thu Oct 14 17:59:00 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Brian Foster X-Patchwork-Id: 12559175 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 AFDB1C433EF for ; Thu, 14 Oct 2021 17:59:08 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 8A63B61037 for ; Thu, 14 Oct 2021 17:59:08 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232809AbhJNSBM (ORCPT ); Thu, 14 Oct 2021 14:01:12 -0400 Received: from us-smtp-delivery-124.mimecast.com ([216.205.24.124]:21478 "EHLO us-smtp-delivery-124.mimecast.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231503AbhJNSBM (ORCPT ); Thu, 14 Oct 2021 14:01:12 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1634234346; h=from:from:reply-to:subject:subject: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=LaMYqMyzbhTJmrwBiI1fJZT7MIMvVgtPRWc6p9mma2s=; b=XJIOord4qArKcM96vQWjlUfB0kZS8Amc9JAmJ8y09KIFjUln3RhsbLIyOL6MDSTT+YZafW bw2q7IH6iNuxFotCVSwW7HdUUKRw9wI99Iwm7KbfqETRxsQm2H5Ignh4rG4P+3MZYLiDh7 Xp7o+uhRO3FIRqmYnAF2AmDG3Q5T59E= Received: from mimecast-mx01.redhat.com (mimecast-mx01.redhat.com [209.132.183.4]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-417-B65wrA1hMSiS4FXb057ReQ-1; Thu, 14 Oct 2021 13:59:05 -0400 X-MC-Unique: B65wrA1hMSiS4FXb057ReQ-1 Received: from smtp.corp.redhat.com (int-mx06.intmail.prod.int.phx2.redhat.com [10.5.11.16]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id 9366E81424E for ; Thu, 14 Oct 2021 17:59:04 +0000 (UTC) Received: from bfoster.redhat.com (unknown [10.22.8.90]) by smtp.corp.redhat.com (Postfix) with ESMTP id 503B05C1A3 for ; Thu, 14 Oct 2021 17:59:04 +0000 (UTC) From: Brian Foster To: linux-xfs@vger.kernel.org Subject: [PATCH v3 2/4] xfs: rename the next_agno perag iteration variable Date: Thu, 14 Oct 2021 13:59:00 -0400 Message-Id: <20211014175902.1519172-3-bfoster@redhat.com> In-Reply-To: <20211014175902.1519172-1-bfoster@redhat.com> References: <20211014175902.1519172-1-bfoster@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.79 on 10.5.11.16 Precedence: bulk List-ID: X-Mailing-List: linux-xfs@vger.kernel.org Rename the next_agno variable to be consistent across the several iteration macros and shorten line length. Signed-off-by: Brian Foster Reviewed-by: Dave Chinner Reviewed-by: Darrick J. Wong --- fs/xfs/libxfs/xfs_ag.h | 18 +++++++++--------- 1 file changed, 9 insertions(+), 9 deletions(-) diff --git a/fs/xfs/libxfs/xfs_ag.h b/fs/xfs/libxfs/xfs_ag.h index ddb89e10b6ea..134e8635dee1 100644 --- a/fs/xfs/libxfs/xfs_ag.h +++ b/fs/xfs/libxfs/xfs_ag.h @@ -127,22 +127,22 @@ void xfs_perag_put(struct xfs_perag *pag); static inline struct xfs_perag * xfs_perag_next( struct xfs_perag *pag, - xfs_agnumber_t *next_agno) + xfs_agnumber_t *agno) { struct xfs_mount *mp = pag->pag_mount; - *next_agno = pag->pag_agno + 1; + *agno = pag->pag_agno + 1; xfs_perag_put(pag); - return xfs_perag_get(mp, *next_agno); + return xfs_perag_get(mp, *agno); } -#define for_each_perag_range(mp, next_agno, end_agno, pag) \ - for ((pag) = xfs_perag_get((mp), (next_agno)); \ - (pag) != NULL && (next_agno) <= (end_agno); \ - (pag) = xfs_perag_next((pag), &(next_agno))) +#define for_each_perag_range(mp, agno, end_agno, pag) \ + for ((pag) = xfs_perag_get((mp), (agno)); \ + (pag) != NULL && (agno) <= (end_agno); \ + (pag) = xfs_perag_next((pag), &(agno))) -#define for_each_perag_from(mp, next_agno, pag) \ - for_each_perag_range((mp), (next_agno), (mp)->m_sb.sb_agcount, (pag)) +#define for_each_perag_from(mp, agno, pag) \ + for_each_perag_range((mp), (agno), (mp)->m_sb.sb_agcount, (pag)) #define for_each_perag(mp, agno, pag) \ From patchwork Thu Oct 14 17:59:01 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Brian Foster X-Patchwork-Id: 12559177 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 8041AC4332F for ; Thu, 14 Oct 2021 17:59:09 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 6526B61152 for ; Thu, 14 Oct 2021 17:59:09 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231503AbhJNSBN (ORCPT ); Thu, 14 Oct 2021 14:01:13 -0400 Received: from us-smtp-delivery-124.mimecast.com ([170.10.133.124]:59871 "EHLO us-smtp-delivery-124.mimecast.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229718AbhJNSBM (ORCPT ); Thu, 14 Oct 2021 14:01:12 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1634234347; h=from:from:reply-to:subject:subject: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=GVJvKnAoK21JZkJlCWiIrcRBgTaMqs7HQ0BrYyZO1FA=; b=H/Y+bJDSEGUM43EttPMd2vIFsilVOwXPgPll+wOlCSeW76wW7T5KtWQA/vpIkZ275MVlAe fFZvIsfw156IRdArtoyfwzTOYJZRbRKrrGa/cTcTRGpWycWmq1aPW6TPQtQmkDPT5K4Wzk TK0EK8JaoQPIn8RJb9ayT1cAF1+I89Q= Received: from mimecast-mx01.redhat.com (mimecast-mx01.redhat.com [209.132.183.4]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-466-ZqRHA6wINAul5XgeUOiEKg-1; Thu, 14 Oct 2021 13:59:05 -0400 X-MC-Unique: ZqRHA6wINAul5XgeUOiEKg-1 Received: from smtp.corp.redhat.com (int-mx06.intmail.prod.int.phx2.redhat.com [10.5.11.16]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id 03B691006AB1 for ; Thu, 14 Oct 2021 17:59:05 +0000 (UTC) Received: from bfoster.redhat.com (unknown [10.22.8.90]) by smtp.corp.redhat.com (Postfix) with ESMTP id B6EBBB8549 for ; Thu, 14 Oct 2021 17:59:04 +0000 (UTC) From: Brian Foster To: linux-xfs@vger.kernel.org Subject: [PATCH v3 3/4] xfs: terminate perag iteration reliably on agcount Date: Thu, 14 Oct 2021 13:59:01 -0400 Message-Id: <20211014175902.1519172-4-bfoster@redhat.com> In-Reply-To: <20211014175902.1519172-1-bfoster@redhat.com> References: <20211014175902.1519172-1-bfoster@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.79 on 10.5.11.16 Precedence: bulk List-ID: X-Mailing-List: linux-xfs@vger.kernel.org The for_each_perag_from() iteration macro relies on sb_agcount to process every perag currently within EOFS from a given starting point. It's perfectly valid to have perag structures beyond sb_agcount, however, such as if a growfs is in progress. If a perag loop happens to race with growfs in this manner, it will actually attempt to process the post-EOFS perag where ->pag_agno == sb_agcount. This is reproduced by xfs/104 and manifests as the following assert failure in superblock write verifier context: XFS: Assertion failed: agno < mp->m_sb.sb_agcount, file: fs/xfs/libxfs/xfs_types.c, line: 22 Update the corresponding macro to only process perags that are within the current sb_agcount. Fixes: 58d43a7e3263 ("xfs: pass perags around in fsmap data dev functions") Signed-off-by: Brian Foster Reviewed-by: Dave Chinner Reviewed-by: Darrick J. Wong --- fs/xfs/libxfs/xfs_ag.h | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/fs/xfs/libxfs/xfs_ag.h b/fs/xfs/libxfs/xfs_ag.h index 134e8635dee1..4585ebb3f450 100644 --- a/fs/xfs/libxfs/xfs_ag.h +++ b/fs/xfs/libxfs/xfs_ag.h @@ -142,7 +142,7 @@ xfs_perag_next( (pag) = xfs_perag_next((pag), &(agno))) #define for_each_perag_from(mp, agno, pag) \ - for_each_perag_range((mp), (agno), (mp)->m_sb.sb_agcount, (pag)) + for_each_perag_range((mp), (agno), (mp)->m_sb.sb_agcount - 1, (pag)) #define for_each_perag(mp, agno, pag) \ From patchwork Thu Oct 14 17:59:02 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Brian Foster X-Patchwork-Id: 12559181 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 1ACA4C433F5 for ; Thu, 14 Oct 2021 17:59:10 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id EE598610EA for ; Thu, 14 Oct 2021 17:59:09 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S233059AbhJNSBN (ORCPT ); Thu, 14 Oct 2021 14:01:13 -0400 Received: from us-smtp-delivery-124.mimecast.com ([170.10.133.124]:38826 "EHLO us-smtp-delivery-124.mimecast.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S233136AbhJNSBN (ORCPT ); Thu, 14 Oct 2021 14:01:13 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1634234348; h=from:from:reply-to:subject:subject: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=6DnwLH6v1rU2RnGOl6QGEKyBjIbo6ISfdN//eUJ8P14=; b=VY443z8PIQPxYX0os93lv1aO4L3XIqckrlwGM3fw+rYB3lyWCoF5CL72RmG8/H/OTw0dSL MiKFw9rsF9i3shVQZ/u5XBJTgN6PeQzgJaNSp/f8+Mv6EOPinygajqsv62LL97422dLcwx mekwkk5PDHhzGz/F83awqWIq5O45nkA= Received: from mimecast-mx01.redhat.com (mimecast-mx01.redhat.com [209.132.183.4]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-136-uBCFse1qNau7MndPWCfQ3Q-1; Thu, 14 Oct 2021 13:59:06 -0400 X-MC-Unique: uBCFse1qNau7MndPWCfQ3Q-1 Received: from smtp.corp.redhat.com (int-mx06.intmail.prod.int.phx2.redhat.com [10.5.11.16]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id 8E5D41006ABA for ; Thu, 14 Oct 2021 17:59:05 +0000 (UTC) Received: from bfoster.redhat.com (unknown [10.22.8.90]) by smtp.corp.redhat.com (Postfix) with ESMTP id 4CBC45C1A3 for ; Thu, 14 Oct 2021 17:59:05 +0000 (UTC) From: Brian Foster To: linux-xfs@vger.kernel.org Subject: [PATCH v3 4/4] xfs: fix perag reference leak on iteration race with growfs Date: Thu, 14 Oct 2021 13:59:02 -0400 Message-Id: <20211014175902.1519172-5-bfoster@redhat.com> In-Reply-To: <20211014175902.1519172-1-bfoster@redhat.com> References: <20211014175902.1519172-1-bfoster@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.79 on 10.5.11.16 Precedence: bulk List-ID: X-Mailing-List: linux-xfs@vger.kernel.org The for_each_perag*() set of macros are hacky in that some (i.e. those based on sb_agcount) rely on the assumption that perag iteration terminates naturally with a NULL perag at the specified end_agno. Others allow for the final AG to have a valid perag and require the calling function to clean up any potential leftover xfs_perag reference on termination of the loop. Aside from providing a subtly inconsistent interface, the former variant is racy with growfs because growfs can create discoverable post-eofs perags before the final superblock update that completes the grow operation and increases sb_agcount. This leads to the following assert failure (reproduced by xfs/104) in the perag free path during unmount: XFS: Assertion failed: atomic_read(&pag->pag_ref) == 0, file: fs/xfs/libxfs/xfs_ag.c, line: 195 This occurs because one of the many for_each_perag() loops in the code that is expected to terminate with a NULL pag (and thus has no post-loop xfs_perag_put() check) raced with a growfs and found a non-NULL post-EOFS perag, but terminated naturally based on the end_agno check without releasing the post-EOFS perag. Rework the iteration logic to lift the agno check from the main for loop conditional to the iteration helper function. The for loop now purely terminates on a NULL pag and xfs_perag_next() avoids taking a reference to any perag beyond end_agno in the first place. Fixes: f250eedcf762 ("xfs: make for_each_perag... a first class citizen") Signed-off-by: Brian Foster Reviewed-by: Dave Chinner Reviewed-by: Darrick J. Wong --- fs/xfs/libxfs/xfs_ag.h | 16 ++++++---------- 1 file changed, 6 insertions(+), 10 deletions(-) diff --git a/fs/xfs/libxfs/xfs_ag.h b/fs/xfs/libxfs/xfs_ag.h index 4585ebb3f450..3f597cad2c33 100644 --- a/fs/xfs/libxfs/xfs_ag.h +++ b/fs/xfs/libxfs/xfs_ag.h @@ -116,30 +116,26 @@ void xfs_perag_put(struct xfs_perag *pag); /* * Perag iteration APIs - * - * XXX: for_each_perag_range() usage really needs an iterator to clean up when - * we terminate at end_agno because we may have taken a reference to the perag - * beyond end_agno. Right now callers have to be careful to catch and clean that - * up themselves. This is not necessary for the callers of for_each_perag() and - * for_each_perag_from() because they terminate at sb_agcount where there are - * no perag structures in tree beyond end_agno. */ static inline struct xfs_perag * xfs_perag_next( struct xfs_perag *pag, - xfs_agnumber_t *agno) + xfs_agnumber_t *agno, + xfs_agnumber_t end_agno) { struct xfs_mount *mp = pag->pag_mount; *agno = pag->pag_agno + 1; xfs_perag_put(pag); + if (*agno > end_agno) + return NULL; return xfs_perag_get(mp, *agno); } #define for_each_perag_range(mp, agno, end_agno, pag) \ for ((pag) = xfs_perag_get((mp), (agno)); \ - (pag) != NULL && (agno) <= (end_agno); \ - (pag) = xfs_perag_next((pag), &(agno))) + (pag) != NULL; \ + (pag) = xfs_perag_next((pag), &(agno), (end_agno))) #define for_each_perag_from(mp, agno, pag) \ for_each_perag_range((mp), (agno), (mp)->m_sb.sb_agcount - 1, (pag))