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 Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by smtp.lore.kernel.org (Postfix) with ESMTP id 8F7F5C433EF for ; Fri, 8 Jul 2022 15:28:37 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id C97E66B0072; Fri, 8 Jul 2022 11:28:36 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id C47396B0073; Fri, 8 Jul 2022 11:28:36 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id B0F446B0074; Fri, 8 Jul 2022 11:28:36 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (smtprelay0011.hostedemail.com [216.40.44.11]) by kanga.kvack.org (Postfix) with ESMTP id A102B6B0072 for ; Fri, 8 Jul 2022 11:28:36 -0400 (EDT) Received: from smtpin03.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay08.hostedemail.com (Postfix) with ESMTP id 5F97220B4D for ; Fri, 8 Jul 2022 15:28:36 +0000 (UTC) X-FDA: 79664314632.03.2AA2AEA Received: from dfw.source.kernel.org (dfw.source.kernel.org [139.178.84.217]) by imf17.hostedemail.com (Postfix) with ESMTP id DFB7240063 for ; Fri, 8 Jul 2022 15:28:35 +0000 (UTC) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by dfw.source.kernel.org (Postfix) with ESMTPS id 85B5860AE0; Fri, 8 Jul 2022 15:28:34 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id DDA87C341C0; Fri, 8 Jul 2022 15:28:33 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1657294113; bh=5LLM7Cns9F5FvxVMK5IvuU4OHW00Kt7A5+RS/2YlNSA=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=qxYu2yBLmGmn5ptn0dHqkO9nJiSNK2GQ9BtHbLGDjk7nUYDPhr85sKxBVg/TG83md OP+CsK+t4Jv9EJ0x8/ZuJB6djKsMi5bg8vJ52JySOH26zyyosqzEXqIj//6+6gl/Cp t7aarVM0kcOullnmKsGw6WyATVGsSzavbuRe20EXaU8Pk94gz60wdoe4MtMllESdxQ QH1mwr5jC1OaACAjlcC4yGQAKYfyBuveyk+bbDbBk+hhQlc6M1rbqAYIE/ntF2VfzS yki9WBxft/JYP14FlBL7Ljfx3isN8lX+54aXDs9+S6AGghGKnpx6yY7ZiButI62hC4 qQg9rO+2P8Wig== Date: Fri, 8 Jul 2022 08:28:33 -0700 From: "Darrick J. Wong" To: "ruansy.fnst@fujitsu.com" Cc: "linux-kernel@vger.kernel.org" , "linux-xfs@vger.kernel.org" , "nvdimm@lists.linux.dev" , "linux-mm@kvack.org" , "linux-fsdevel@vger.kernel.org" , "dan.j.williams@intel.com" , "david@fromorbit.com" , "hch@infradead.org" , "jane.chu@oracle.com" Subject: Re: [RFC PATCH v5] mm, pmem, xfs: Introduce MF_MEM_REMOVE for unbind Message-ID: References: <20220410171623.3788004-1-ruansy.fnst@fujitsu.com> <20220708054216.825004-1-ruansy.fnst@fujitsu.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20220708054216.825004-1-ruansy.fnst@fujitsu.com> ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=hostedemail.com; s=arc-20220608; t=1657294116; h=from:from:sender:reply-to:subject:subject:date:date: message-id:message-id:to:to:cc:cc:mime-version:mime-version: content-type:content-type:content-transfer-encoding: in-reply-to:in-reply-to:references:references:dkim-signature; bh=gnzzHFGyOUfDHITMYpo87QL6BFVuIJ3CWw0vjgfIIec=; b=QGjA1vua2O8Fe1sFTjRH9gypivGuOhKZjUgsT5VsHPMZfSbllwUofJco+B8tCjw0Ho91gA kKP0Ag2pgi3NSmnlXYJzx3tNPIP4C9p/B0xjJrVDvoZOO81lAg6oKcCmR2X6XnwSMrDlDz wWkoaer8/PyzzTjfuFVYf9IwIfRnWSg= ARC-Seal: i=1; s=arc-20220608; d=hostedemail.com; t=1657294116; a=rsa-sha256; cv=none; b=Ia8S5P29TTRO2p+nEmgMmorXwws0EfNnzqO7R9XPWOwLrSNFbnf0qM8V5UMWWIjWO6QIHj nsA9KuaALv+c/s/KZ+/zf1SfGGu7tTw2T2+Oqp5WLfjEbBOMleaSJyUJ3XKNpcdyZVokbx Bt9Du7ouQVatl8keC9zVVKAJZPPorT0= ARC-Authentication-Results: i=1; imf17.hostedemail.com; dkim=pass header.d=kernel.org header.s=k20201202 header.b=qxYu2yBL; dmarc=pass (policy=none) header.from=kernel.org; spf=pass (imf17.hostedemail.com: domain of djwong@kernel.org designates 139.178.84.217 as permitted sender) smtp.mailfrom=djwong@kernel.org Authentication-Results: imf17.hostedemail.com; dkim=pass header.d=kernel.org header.s=k20201202 header.b=qxYu2yBL; dmarc=pass (policy=none) header.from=kernel.org; spf=pass (imf17.hostedemail.com: domain of djwong@kernel.org designates 139.178.84.217 as permitted sender) smtp.mailfrom=djwong@kernel.org X-Rspamd-Server: rspam12 X-Rspamd-Queue-Id: DFB7240063 X-Stat-Signature: ww53e1oaj8nnijdsnccge4i8mxab1o4q X-Rspam-User: X-HE-Tag: 1657294115-41829 X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: On Fri, Jul 08, 2022 at 05:42:22AM +0000, ruansy.fnst@fujitsu.com wrote: > This patch is inspired by Dan's "mm, dax, pmem: Introduce > dev_pagemap_failure()"[1]. With the help of dax_holder and > ->notify_failure() mechanism, the pmem driver is able to ask filesystem > (or mapped device) on it to unmap all files in use and notify processes > who are using those files. > > Call trace: > trigger unbind > -> unbind_store() > -> ... (skip) > -> devres_release_all() # was pmem driver ->remove() in v1 > -> kill_dax() > -> dax_holder_notify_failure(dax_dev, 0, U64_MAX, MF_MEM_REMOVE) > -> xfs_dax_notify_failure() > > Introduce MF_MEM_REMOVE to let filesystem know this is a remove event. > So do not shutdown filesystem directly if something not supported, or if > failure range includes metadata area. Make sure all files and processes > are handled correctly. > > == > Changes since v4: > 1. sync_filesystem() at the beginning when MF_MEM_REMOVE > 2. Rebased on next-20220706 > > Changes since v3: > 1. Flush dirty files and logs when pmem is about to be removed. > 2. Rebased on next-20220701 > > Changes since v2: > 1. Rebased on next-20220615 > > Changes since v1: > 1. Drop the needless change of moving {kill,put}_dax() > 2. Rebased on '[PATCHSETS] v14 fsdax-rmap + v11 fsdax-reflink'[2] > > [1]: https://lore.kernel.org/linux-mm/161604050314.1463742.14151665140035795571.stgit@dwillia2-desk3.amr.corp.intel.com/ > [2]: https://lore.kernel.org/linux-xfs/20220508143620.1775214-1-ruansy.fnst@fujitsu.com/ > > Signed-off-by: Shiyang Ruan > --- > drivers/dax/super.c | 2 +- > fs/xfs/xfs_notify_failure.c | 16 ++++++++++++++++ > include/linux/mm.h | 1 + > 3 files changed, 18 insertions(+), 1 deletion(-) > > diff --git a/drivers/dax/super.c b/drivers/dax/super.c > index 9b5e2a5eb0ae..d4bc83159d46 100644 > --- a/drivers/dax/super.c > +++ b/drivers/dax/super.c > @@ -323,7 +323,7 @@ void kill_dax(struct dax_device *dax_dev) > return; > > if (dax_dev->holder_data != NULL) > - dax_holder_notify_failure(dax_dev, 0, U64_MAX, 0); > + dax_holder_notify_failure(dax_dev, 0, U64_MAX, MF_MEM_REMOVE); > > clear_bit(DAXDEV_ALIVE, &dax_dev->flags); > synchronize_srcu(&dax_srcu); > diff --git a/fs/xfs/xfs_notify_failure.c b/fs/xfs/xfs_notify_failure.c > index aa8dc27c599c..728b0c1d0ddf 100644 > --- a/fs/xfs/xfs_notify_failure.c > +++ b/fs/xfs/xfs_notify_failure.c > @@ -18,6 +18,7 @@ > #include "xfs_rmap_btree.h" > #include "xfs_rtalloc.h" > #include "xfs_trans.h" > +#include "xfs_log.h" > > #include > #include > @@ -75,6 +76,10 @@ xfs_dax_failure_fn( > > if (XFS_RMAP_NON_INODE_OWNER(rec->rm_owner) || > (rec->rm_flags & (XFS_RMAP_ATTR_FORK | XFS_RMAP_BMBT_BLOCK))) { > + /* Do not shutdown so early when device is to be removed */ > + if (notify->mf_flags & MF_MEM_REMOVE) { > + return 0; > + } Nit: no curly braces needed here. > xfs_force_shutdown(mp, SHUTDOWN_CORRUPT_ONDISK); > return -EFSCORRUPTED; > } > @@ -168,6 +173,14 @@ xfs_dax_notify_failure( > struct xfs_mount *mp = dax_holder(dax_dev); > u64 ddev_start; > u64 ddev_end; > + int error; > + > + if (mf_flags & MF_MEM_REMOVE) { > + xfs_info(mp, "device is about to be removed!"); > + error = sync_filesystem(mp->m_super); sync_filesystem requires callers to hold s_umount. Does the dax media failure code take that lock for us, or is this missing a lock? Also, I'm not sure it's a good idea to sync_filesystem() before checking if SB_BORN has been set. > + if (error) > + return error; > + } > > if (!(mp->m_sb.sb_flags & SB_BORN)) { > xfs_warn(mp, "filesystem is not ready for notify_failure()!"); > @@ -182,6 +195,9 @@ xfs_dax_notify_failure( > > if (mp->m_logdev_targp && mp->m_logdev_targp->bt_daxdev == dax_dev && > mp->m_logdev_targp != mp->m_ddev_targp) { > + if (mf_flags & MF_MEM_REMOVE) { > + return 0; > + } Same nit about not needing curly braces. > xfs_err(mp, "ondisk log corrupt, shutting down fs!"); > xfs_force_shutdown(mp, SHUTDOWN_CORRUPT_ONDISK); > return -EFSCORRUPTED; > diff --git a/include/linux/mm.h b/include/linux/mm.h > index 794ad19b57f8..3eab2d7ba884 100644 > --- a/include/linux/mm.h > +++ b/include/linux/mm.h > @@ -3240,6 +3240,7 @@ enum mf_flags { > MF_UNPOISON = 1 << 4, > MF_SW_SIMULATED = 1 << 5, > MF_NO_RETRY = 1 << 6, > + MF_MEM_REMOVE = 1 << 7, This is more of a pre-removal notification, right? I think the flag value ought to be named that way too (MF_MEM_PRE_REMOVE). --D > }; > int mf_dax_kill_procs(struct address_space *mapping, pgoff_t index, > unsigned long count, int mf_flags); > -- > 2.37.0