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 vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 778D2C433F5 for ; Wed, 5 Jan 2022 19:06:11 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S243334AbiAETGK (ORCPT ); Wed, 5 Jan 2022 14:06:10 -0500 Received: from dfw.source.kernel.org ([139.178.84.217]:60600 "EHLO dfw.source.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S243317AbiAETGJ (ORCPT ); Wed, 5 Jan 2022 14:06:09 -0500 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 A2C65617E8; Wed, 5 Jan 2022 19:06:08 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 047E5C36AE9; Wed, 5 Jan 2022 19:06:07 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1641409568; bh=ztzxbkalbIPb30j4PLPt7jHsX6mRQuIWYMcP+uqwvmQ=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=aT67lFvl11sy9BIgecg0Kz380qFY+pYepVbhAUFLy7PEyjgor69LxPqBjXdayt/e/ C0gyhb1wUPKgvkGTVI4wlxWQ0xGjkDpywELvRhkB9DFbL8AOD4IICNKTEu1t9Cq/dT m8vT7XHura2XbBcDoUeGm6pvUmST7COe5ziWW0RnfHuNGIRbMOrk0+o7K/MKqYi5k+ 22E5+yGJKj77XTFMfTMA6KXaHbTRZ1YGXU4K5SCFMpjrxKpDBpYPHgmv+19P2gFdtu vulXlgXM+O8G3YKkvsmeb/0lfNLRVJ8+MDt7tJIy4BSQc+OQ4AFZzM8/scBXZC8Rgc Zj01m1diKnDig== Date: Wed, 5 Jan 2022 11:06:07 -0800 From: "Darrick J. Wong" To: Shiyang Ruan 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, Christoph Hellwig Subject: Re: [PATCH v9 04/10] pagemap,pmem: Introduce ->memory_failure() Message-ID: <20220105190607.GF398655@magnolia> References: <20211226143439.3985960-1-ruansy.fnst@fujitsu.com> <20211226143439.3985960-5-ruansy.fnst@fujitsu.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20211226143439.3985960-5-ruansy.fnst@fujitsu.com> Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Sun, Dec 26, 2021 at 10:34:33PM +0800, Shiyang Ruan wrote: > When memory-failure occurs, we call this function which is implemented > by each kind of devices. For the fsdax case, pmem device driver > implements it. Pmem device driver will find out the filesystem in which > the corrupted page located in. > > With dax_holder notify support, we are able to notify the memory failure > from pmem driver to upper layers. If there is something not support in > the notify routine, memory_failure will fall back to the generic hanlder. > > Signed-off-by: Shiyang Ruan > Reviewed-by: Christoph Hellwig > --- > drivers/nvdimm/pmem.c | 16 ++++++++++++++++ > include/linux/memremap.h | 9 +++++++++ > mm/memory-failure.c | 14 ++++++++++++++ > 3 files changed, 39 insertions(+) > > diff --git a/drivers/nvdimm/pmem.c b/drivers/nvdimm/pmem.c > index 4190c8c46ca8..2114554358eb 100644 > --- a/drivers/nvdimm/pmem.c > +++ b/drivers/nvdimm/pmem.c > @@ -386,6 +386,20 @@ static void pmem_release_disk(void *__pmem) > blk_cleanup_disk(pmem->disk); > } > > +static int pmem_pagemap_memory_failure(struct dev_pagemap *pgmap, > + unsigned long pfn, u64 len, int mf_flags) > +{ > + struct pmem_device *pmem = > + container_of(pgmap, struct pmem_device, pgmap); > + loff_t offset = PFN_PHYS(pfn) - pmem->phys_addr - pmem->data_offset; Use u64 here ^^^ because this isn't a file offset, this is a physical offset. Also, loff_t is signed, which you probably don't want. > + > + return dax_holder_notify_failure(pmem->dax_dev, offset, len, mf_flags); > +} > + > +static const struct dev_pagemap_ops fsdax_pagemap_ops = { > + .memory_failure = pmem_pagemap_memory_failure, > +}; > + > static int pmem_attach_disk(struct device *dev, > struct nd_namespace_common *ndns) > { > @@ -448,6 +462,7 @@ static int pmem_attach_disk(struct device *dev, > pmem->pfn_flags = PFN_DEV; > if (is_nd_pfn(dev)) { > pmem->pgmap.type = MEMORY_DEVICE_FS_DAX; > + pmem->pgmap.ops = &fsdax_pagemap_ops; > addr = devm_memremap_pages(dev, &pmem->pgmap); > pfn_sb = nd_pfn->pfn_sb; > pmem->data_offset = le64_to_cpu(pfn_sb->dataoff); > @@ -461,6 +476,7 @@ static int pmem_attach_disk(struct device *dev, > pmem->pgmap.range.end = res->end; > pmem->pgmap.nr_range = 1; > pmem->pgmap.type = MEMORY_DEVICE_FS_DAX; > + pmem->pgmap.ops = &fsdax_pagemap_ops; > addr = devm_memremap_pages(dev, &pmem->pgmap); > pmem->pfn_flags |= PFN_MAP; > bb_range = pmem->pgmap.range; > diff --git a/include/linux/memremap.h b/include/linux/memremap.h > index c0e9d35889e8..820c2f33b163 100644 > --- a/include/linux/memremap.h > +++ b/include/linux/memremap.h > @@ -87,6 +87,15 @@ struct dev_pagemap_ops { > * the page back to a CPU accessible page. > */ > vm_fault_t (*migrate_to_ram)(struct vm_fault *vmf); > + > + /* > + * Handle the memory failure happens on a range of pfns. Notify the > + * processes who are using these pfns, and try to recover the data on > + * them if necessary. The mf_flags is finally passed to the recover > + * function through the whole notify routine. Might want to state here that the generic implementation will be used if ->memory_failure is NULL or calling the function returns -EOPNOTSUPP. --D > + */ > + int (*memory_failure)(struct dev_pagemap *pgmap, unsigned long pfn, > + u64 len, int mf_flags); > }; > > #define PGMAP_ALTMAP_VALID (1 << 0) > diff --git a/mm/memory-failure.c b/mm/memory-failure.c > index 1ee7d626fed7..3cc612b29f89 100644 > --- a/mm/memory-failure.c > +++ b/mm/memory-failure.c > @@ -1625,6 +1625,20 @@ static int memory_failure_dev_pagemap(unsigned long pfn, int flags, > if (!pgmap_pfn_valid(pgmap, pfn)) > goto out; > > + /* > + * Call driver's implementation to handle the memory failure, otherwise > + * fall back to generic handler. > + */ > + if (pgmap->ops->memory_failure) { > + rc = pgmap->ops->memory_failure(pgmap, pfn, PAGE_SIZE, flags); > + /* > + * Fall back to generic handler too if operation is not > + * supported inside the driver/device/filesystem. > + */ > + if (rc != -EOPNOTSUPP) > + goto out; > + } > + > rc = mf_generic_kill_procs(pfn, flags, pgmap); > out: > /* drop pgmap ref acquired in caller */ > -- > 2.34.1 > > >