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 6B133C433F5 for ; Thu, 21 Apr 2022 08:24:28 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id CA7D76B0071; Thu, 21 Apr 2022 04:24:27 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id C62846B0073; Thu, 21 Apr 2022 04:24:27 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id B46276B0074; Thu, 21 Apr 2022 04:24:27 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (relay.a.hostedemail.com [64.99.140.24]) by kanga.kvack.org (Postfix) with ESMTP id A12326B0071 for ; Thu, 21 Apr 2022 04:24:27 -0400 (EDT) Received: from smtpin03.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay13.hostedemail.com (Postfix) with ESMTP id 63F1962BDD for ; Thu, 21 Apr 2022 08:24:27 +0000 (UTC) X-FDA: 79380199374.03.D6AFE9F Received: from szxga01-in.huawei.com (szxga01-in.huawei.com [45.249.212.187]) by imf06.hostedemail.com (Postfix) with ESMTP id 9AE15180024 for ; Thu, 21 Apr 2022 08:24:25 +0000 (UTC) Received: from canpemm500002.china.huawei.com (unknown [172.30.72.53]) by szxga01-in.huawei.com (SkyGuard) with ESMTP id 4KkVtK5wCFzfYtX; Thu, 21 Apr 2022 16:23:37 +0800 (CST) Received: from [10.174.177.76] (10.174.177.76) by canpemm500002.china.huawei.com (7.192.104.244) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2375.24; Thu, 21 Apr 2022 16:24:23 +0800 Subject: Re: [PATCH v13 3/7] pagemap,pmem: Introduce ->memory_failure() To: Shiyang Ruan CC: , , , , , Christoph Hellwig , , , , , References: <20220419045045.1664996-1-ruansy.fnst@fujitsu.com> <20220419045045.1664996-4-ruansy.fnst@fujitsu.com> From: Miaohe Lin Message-ID: Date: Thu, 21 Apr 2022 16:24:23 +0800 User-Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:78.0) Gecko/20100101 Thunderbird/78.6.0 MIME-Version: 1.0 In-Reply-To: <20220419045045.1664996-4-ruansy.fnst@fujitsu.com> Content-Type: text/plain; charset="utf-8" Content-Language: en-US Content-Transfer-Encoding: 7bit X-Originating-IP: [10.174.177.76] X-ClientProxiedBy: dggems702-chm.china.huawei.com (10.3.19.179) To canpemm500002.china.huawei.com (7.192.104.244) X-CFilter-Loop: Reflected X-Rspam-User: X-Rspamd-Server: rspam06 X-Rspamd-Queue-Id: 9AE15180024 X-Stat-Signature: 6j1t1poc35gaqo79kn6kq3cqe9jnycqh Authentication-Results: imf06.hostedemail.com; dkim=none; spf=pass (imf06.hostedemail.com: domain of linmiaohe@huawei.com designates 45.249.212.187 as permitted sender) smtp.mailfrom=linmiaohe@huawei.com; dmarc=pass (policy=quarantine) header.from=huawei.com X-HE-Tag: 1650529465-926819 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 2022/4/19 12:50, 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 > Reviewed-by: Dan Williams > --- > drivers/nvdimm/pmem.c | 17 +++++++++++++++++ > include/linux/memremap.h | 12 ++++++++++++ > mm/memory-failure.c | 14 ++++++++++++++ > 3 files changed, 43 insertions(+) > > diff --git a/drivers/nvdimm/pmem.c b/drivers/nvdimm/pmem.c > index 58d95242a836..bd502957cfdf 100644 > --- a/drivers/nvdimm/pmem.c > +++ b/drivers/nvdimm/pmem.c > @@ -366,6 +366,21 @@ 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, unsigned long nr_pages, int mf_flags) > +{ > + struct pmem_device *pmem = > + container_of(pgmap, struct pmem_device, pgmap); > + u64 offset = PFN_PHYS(pfn) - pmem->phys_addr - pmem->data_offset; > + u64 len = nr_pages << PAGE_SHIFT; > + > + 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) > { > @@ -427,6 +442,7 @@ 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); > @@ -440,6 +456,7 @@ 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 ad6062d736cd..bcfb6bf4ce5a 100644 > --- a/include/linux/memremap.h > +++ b/include/linux/memremap.h > @@ -79,6 +79,18 @@ 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. > + * > + * When this is not implemented, or it returns -EOPNOTSUPP, the caller > + * will fall back to a common handler called mf_generic_kill_procs(). > + */ > + int (*memory_failure)(struct dev_pagemap *pgmap, unsigned long pfn, > + unsigned long nr_pages, int mf_flags); > }; > > #define PGMAP_ALTMAP_VALID (1 << 0) > diff --git a/mm/memory-failure.c b/mm/memory-failure.c > index 7c8c047bfdc8..a40e79e634a4 100644 > --- a/mm/memory-failure.c > +++ b/mm/memory-failure.c > @@ -1741,6 +1741,20 @@ 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, 1, flags); > + /* > + * Fall back to generic handler too if operation is not > + * supported inside the driver/device/filesystem. > + */ > + if (rc != -EOPNOTSUPP) > + goto out; > + } > + Thanks for your patch. There are two questions: 1.Is dax_lock_page + dax_unlock_page pair needed here? 2.hwpoison_filter and SetPageHWPoison will be handled by the callback or they're just ignored deliberately? Thanks! > rc = mf_generic_kill_procs(pfn, flags, pgmap); > out: > /* drop pgmap ref acquired in caller */ >