From patchwork Tue Sep 15 10:13:10 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Ruan Shiyang X-Patchwork-Id: 11775985 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 70889618 for ; Tue, 15 Sep 2020 10:13:53 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 4571021D95 for ; Tue, 15 Sep 2020 10:13:53 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726384AbgIOKNc (ORCPT ); Tue, 15 Sep 2020 06:13:32 -0400 Received: from mail.cn.fujitsu.com ([183.91.158.132]:44316 "EHLO heian.cn.fujitsu.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1726134AbgIOKN3 (ORCPT ); Tue, 15 Sep 2020 06:13:29 -0400 X-IronPort-AV: E=Sophos;i="5.76,429,1592841600"; d="scan'208";a="99252003" Received: from unknown (HELO cn.fujitsu.com) ([10.167.33.5]) by heian.cn.fujitsu.com with ESMTP; 15 Sep 2020 18:13:19 +0800 Received: from G08CNEXMBPEKD04.g08.fujitsu.local (unknown [10.167.33.201]) by cn.fujitsu.com (Postfix) with ESMTP id DFECE48990EE; Tue, 15 Sep 2020 18:13:18 +0800 (CST) Received: from G08CNEXCHPEKD05.g08.fujitsu.local (10.167.33.203) by G08CNEXMBPEKD04.g08.fujitsu.local (10.167.33.201) with Microsoft SMTP Server (TLS) id 15.0.1497.2; Tue, 15 Sep 2020 18:13:17 +0800 Received: from localhost.localdomain (10.167.225.141) by G08CNEXCHPEKD05.g08.fujitsu.local (10.167.33.209) with Microsoft SMTP Server id 15.0.1497.2 via Frontend Transport; Tue, 15 Sep 2020 18:13:17 +0800 From: Shiyang Ruan To: , , , CC: , , , , , , , Subject: [RFC PATCH 3/4] mm, fsdax: refactor dax handler in memory-failure Date: Tue, 15 Sep 2020 18:13:10 +0800 Message-ID: <20200915101311.144269-4-ruansy.fnst@cn.fujitsu.com> X-Mailer: git-send-email 2.28.0 In-Reply-To: <20200915101311.144269-1-ruansy.fnst@cn.fujitsu.com> References: <20200915101311.144269-1-ruansy.fnst@cn.fujitsu.com> MIME-Version: 1.0 X-yoursite-MailScanner-ID: DFECE48990EE.A289A X-yoursite-MailScanner: Found to be clean X-yoursite-MailScanner-From: ruansy.fnst@cn.fujitsu.com X-Spam-Status: No Sender: linux-xfs-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-xfs@vger.kernel.org With the ->memory_failure() implemented in pmem device and ->storage_lost() in XFS, we are able to track files or metadata and process them further. We don't track files by page->mapping, page->index any more, so some of functions who obtain ->mapping, ->index from struct page parameter need to be changed by directly passing mapping and index. Signed-off-by: Shiyang Ruan --- fs/dax.c | 18 +++---- include/linux/dax.h | 5 +- include/linux/mm.h | 8 +++ mm/memory-failure.c | 127 +++++++++++++++++++++++++++----------------- 4 files changed, 94 insertions(+), 64 deletions(-) diff --git a/fs/dax.c b/fs/dax.c index 95341af1a966..1ec592f0aadd 100644 --- a/fs/dax.c +++ b/fs/dax.c @@ -379,14 +379,14 @@ static struct page *dax_busy_page(void *entry) } /* - * dax_lock_mapping_entry - Lock the DAX entry corresponding to a page + * dax_lock - Lock the DAX entry corresponding to a page * @page: The page whose entry we want to lock * * Context: Process context. * Return: A cookie to pass to dax_unlock_page() or 0 if the entry could * not be locked. */ -dax_entry_t dax_lock_page(struct page *page) +dax_entry_t dax_lock(struct address_space *mapping, pgoff_t index) { XA_STATE(xas, NULL, 0); void *entry; @@ -394,8 +394,6 @@ dax_entry_t dax_lock_page(struct page *page) /* Ensure page->mapping isn't freed while we look at it */ rcu_read_lock(); for (;;) { - struct address_space *mapping = READ_ONCE(page->mapping); - entry = NULL; if (!mapping || !dax_mapping(mapping)) break; @@ -413,11 +411,7 @@ dax_entry_t dax_lock_page(struct page *page) xas.xa = &mapping->i_pages; xas_lock_irq(&xas); - if (mapping != page->mapping) { - xas_unlock_irq(&xas); - continue; - } - xas_set(&xas, page->index); + xas_set(&xas, index); entry = xas_load(&xas); if (dax_is_locked(entry)) { rcu_read_unlock(); @@ -433,10 +427,10 @@ dax_entry_t dax_lock_page(struct page *page) return (dax_entry_t)entry; } -void dax_unlock_page(struct page *page, dax_entry_t cookie) +void dax_unlock(struct address_space *mapping, pgoff_t index, + dax_entry_t cookie) { - struct address_space *mapping = page->mapping; - XA_STATE(xas, &mapping->i_pages, page->index); + XA_STATE(xas, &mapping->i_pages, index); if (S_ISCHR(mapping->host->i_mode)) return; diff --git a/include/linux/dax.h b/include/linux/dax.h index 6904d4e0b2e0..669ba768b89e 100644 --- a/include/linux/dax.h +++ b/include/linux/dax.h @@ -141,8 +141,9 @@ int dax_writeback_mapping_range(struct address_space *mapping, struct dax_device *dax_dev, struct writeback_control *wbc); struct page *dax_layout_busy_page(struct address_space *mapping); -dax_entry_t dax_lock_page(struct page *page); -void dax_unlock_page(struct page *page, dax_entry_t cookie); +dax_entry_t dax_lock(struct address_space *mapping, pgoff_t index); +void dax_unlock(struct address_space *mapping, pgoff_t index, + dax_entry_t cookie); #else static inline bool bdev_dax_supported(struct block_device *bdev, int blocksize) diff --git a/include/linux/mm.h b/include/linux/mm.h index 3f0c36e1bf3d..d170b3f74d83 100644 --- a/include/linux/mm.h +++ b/include/linux/mm.h @@ -1126,6 +1126,14 @@ static inline bool is_device_private_page(const struct page *page) page->pgmap->type == MEMORY_DEVICE_PRIVATE; } +static inline bool is_device_fsdax_page(const struct page *page) +{ + return IS_ENABLED(CONFIG_DEV_PAGEMAP_OPS) && + IS_ENABLED(CONFIG_DEVICE_PRIVATE) && + is_zone_device_page(page) && + page->pgmap->type == MEMORY_DEVICE_FS_DAX; +} + static inline bool is_pci_p2pdma_page(const struct page *page) { return IS_ENABLED(CONFIG_DEV_PAGEMAP_OPS) && diff --git a/mm/memory-failure.c b/mm/memory-failure.c index f1aa6433f404..0c4a25bf276f 100644 --- a/mm/memory-failure.c +++ b/mm/memory-failure.c @@ -93,6 +93,9 @@ static int hwpoison_filter_dev(struct page *p) if (PageSlab(p)) return -EINVAL; + if (is_device_fsdax_page(p)) + return 0; + mapping = page_mapping(p); if (mapping == NULL || mapping->host == NULL) return -EINVAL; @@ -263,9 +266,8 @@ void shake_page(struct page *p, int access) EXPORT_SYMBOL_GPL(shake_page); static unsigned long dev_pagemap_mapping_shift(struct page *page, - struct vm_area_struct *vma) + struct vm_area_struct *vma, unsigned long address) { - unsigned long address = vma_address(page, vma); pgd_t *pgd; p4d_t *p4d; pud_t *pud; @@ -306,8 +308,8 @@ static unsigned long dev_pagemap_mapping_shift(struct page *page, * Uses GFP_ATOMIC allocations to avoid potential recursions in the VM. */ static void add_to_kill(struct task_struct *tsk, struct page *p, - struct vm_area_struct *vma, - struct list_head *to_kill) + struct address_space *mapping, pgoff_t pgoff, + struct vm_area_struct *vma, struct list_head *to_kill) { struct to_kill *tk; @@ -317,12 +319,18 @@ static void add_to_kill(struct task_struct *tsk, struct page *p, return; } - tk->addr = page_address_in_vma(p, vma); - if (is_zone_device_page(p)) - tk->size_shift = dev_pagemap_mapping_shift(p, vma); - else - tk->size_shift = page_shift(compound_head(p)); - + if (is_device_fsdax_page(p)) { + tk->addr = vma->vm_start + + ((pgoff - vma->vm_pgoff) << PAGE_SHIFT); + tk->size_shift = dev_pagemap_mapping_shift(p, vma, tk->addr); + } else { + tk->addr = page_address_in_vma(p, vma); + if (is_zone_device_page(p)) { + tk->size_shift = dev_pagemap_mapping_shift(p, vma, + vma_address(p, vma)); + } else + tk->size_shift = page_shift(compound_head(p)); + } /* * Send SIGKILL if "tk->addr == -EFAULT". Also, as * "tk->size_shift" is always non-zero for !is_zone_device_page(), @@ -468,7 +476,7 @@ static void collect_procs_anon(struct page *page, struct list_head *to_kill, if (!page_mapped_in_vma(page, vma)) continue; if (vma->vm_mm == t->mm) - add_to_kill(t, page, vma, to_kill); + add_to_kill(t, page, NULL, 0, vma, to_kill); } } read_unlock(&tasklist_lock); @@ -478,23 +486,19 @@ static void collect_procs_anon(struct page *page, struct list_head *to_kill, /* * Collect processes when the error hit a file mapped page. */ -static void collect_procs_file(struct page *page, struct list_head *to_kill, - int force_early) +static void collect_procs_file(struct page *page, struct address_space *mapping, + pgoff_t pgoff, struct list_head *to_kill, int force_early) { struct vm_area_struct *vma; struct task_struct *tsk; - struct address_space *mapping = page->mapping; i_mmap_lock_read(mapping); read_lock(&tasklist_lock); for_each_process(tsk) { - pgoff_t pgoff = page_to_pgoff(page); struct task_struct *t = task_early_kill(tsk, force_early); - if (!t) continue; - vma_interval_tree_foreach(vma, &mapping->i_mmap, pgoff, - pgoff) { + vma_interval_tree_foreach(vma, &mapping->i_mmap, pgoff, pgoff) { /* * Send early kill signal to tasks where a vma covers * the page but the corrupted page is not necessarily @@ -502,8 +506,10 @@ static void collect_procs_file(struct page *page, struct list_head *to_kill, * Assume applications who requested early kill want * to be informed of all such data corruptions. */ - if (vma->vm_mm == t->mm) - add_to_kill(t, page, vma, to_kill); + if (vma->vm_mm == t->mm) { + add_to_kill(t, page, mapping, pgoff, vma, + to_kill); + } } } read_unlock(&tasklist_lock); @@ -522,7 +528,8 @@ static void collect_procs(struct page *page, struct list_head *tokill, if (PageAnon(page)) collect_procs_anon(page, tokill, force_early); else - collect_procs_file(page, tokill, force_early); + collect_procs_file(page, page->mapping, page_to_pgoff(page), + tokill, force_early); } static const char *action_name[] = { @@ -1176,14 +1183,14 @@ static int memory_failure_hugetlb(unsigned long pfn, int flags) return res; } -static int memory_failure_dev_pagemap(unsigned long pfn, int flags, - struct dev_pagemap *pgmap) +static int memory_failure_dev_pagemap_kill_procs(unsigned long pfn, int flags, + struct address_space *mapping, pgoff_t index) { struct page *page = pfn_to_page(pfn); const bool unmap_success = true; unsigned long size = 0; struct to_kill *tk; - LIST_HEAD(tokill); + LIST_HEAD(to_kill); int rc = -EBUSY; loff_t start; dax_entry_t cookie; @@ -1195,28 +1202,9 @@ static int memory_failure_dev_pagemap(unsigned long pfn, int flags, * also prevents changes to the mapping of this pfn until * poison signaling is complete. */ - cookie = dax_lock_page(page); + cookie = dax_lock(mapping, index); if (!cookie) - goto out; - - if (hwpoison_filter(page)) { - rc = 0; goto unlock; - } - - if (pgmap->type == MEMORY_DEVICE_PRIVATE) { - /* - * TODO: Handle HMM pages which may need coordination - * with device-side memory. - */ - goto unlock; - } - - /* - * Use this flag as an indication that the dax page has been - * remapped UC to prevent speculative consumption of poison. - */ - SetPageHWPoison(page); /* * Unlike System-RAM there is no possibility to swap in a @@ -1225,9 +1213,10 @@ static int memory_failure_dev_pagemap(unsigned long pfn, int flags, * SIGBUS (i.e. MF_MUST_KILL) */ flags |= MF_ACTION_REQUIRED | MF_MUST_KILL; - collect_procs(page, &tokill, flags & MF_ACTION_REQUIRED); + collect_procs_file(page, mapping, index, &to_kill, + flags & MF_ACTION_REQUIRED); - list_for_each_entry(tk, &tokill, nd) + list_for_each_entry(tk, &to_kill, nd) if (tk->size_shift) size = max(size, 1UL << tk->size_shift); if (size) { @@ -1237,13 +1226,51 @@ static int memory_failure_dev_pagemap(unsigned long pfn, int flags, * actual size of the mapping being torn down is * communicated in siginfo, see kill_proc() */ - start = (page->index << PAGE_SHIFT) & ~(size - 1); - unmap_mapping_range(page->mapping, start, start + size, 0); + start = (index << PAGE_SHIFT) & ~(size - 1); + unmap_mapping_range(mapping, start, start + size, 0); } - kill_procs(&tokill, flags & MF_MUST_KILL, !unmap_success, pfn, flags); + + kill_procs(&to_kill, flags & MF_MUST_KILL, !unmap_success, pfn, flags); rc = 0; unlock: - dax_unlock_page(page, cookie); + dax_unlock(mapping, index, cookie); + return rc; +} + +static int memory_failure_dev_pagemap(unsigned long pfn, int flags, + struct dev_pagemap *pgmap) +{ + struct page *page = pfn_to_page(pfn); + struct mf_recover_controller mfrc = { + .recover_fn = memory_failure_dev_pagemap_kill_procs, + .pfn = pfn, + .flags = flags, + }; + int rc; + + if (pgmap->type == MEMORY_DEVICE_PRIVATE) { + /* + * TODO: Handle HMM pages which may need coordination + * with device-side memory. + */ + goto out; + } + + if (hwpoison_filter(page)) { + rc = 0; + goto out; + } + + /* + * Use this flag as an indication that the dax page has been + * remapped UC to prevent speculative consumption of poison. + */ + SetPageHWPoison(page); + + /* call driver to handle the memory failure */ + if (pgmap->ops->memory_failure) + rc = pgmap->ops->memory_failure(pgmap, &mfrc); + out: /* drop pgmap ref acquired in caller */ put_dev_pagemap(pgmap);