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 AE4F9C433EF for ; Tue, 19 Apr 2022 04:51:05 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id 86E0B8D0032; Tue, 19 Apr 2022 00:51:00 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 6E6E28D0047; Tue, 19 Apr 2022 00:51:00 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 5385C8D0032; Tue, 19 Apr 2022 00:51:00 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0060.hostedemail.com [216.40.44.60]) by kanga.kvack.org (Postfix) with ESMTP id 2BE818D0047 for ; Tue, 19 Apr 2022 00:51:00 -0400 (EDT) Received: from smtpin27.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay02.hostedemail.com (Postfix) with ESMTP id DB35FA3EC9 for ; Tue, 19 Apr 2022 04:50:59 +0000 (UTC) X-FDA: 79372403838.27.C468DFF Received: from heian.cn.fujitsu.com (mail.cn.fujitsu.com [183.91.158.132]) by imf23.hostedemail.com (Postfix) with ESMTP id C2869140008 for ; Tue, 19 Apr 2022 04:50:57 +0000 (UTC) IronPort-Data: =?us-ascii?q?A9a23=3AnGEvpKBWu5IKkhVW/1biw5YqxClBgxIJ4g17XOL?= =?us-ascii?q?fAQaw024g1DNSyzcaUGqCa6uCZDT3eN5zbojl8RlXv5+Ax9UxeLYW3SszFioV8?= =?us-ascii?q?6IpJjg4wn/YZnrUdouaJK5ex512huLocYZkHhcwmj/3auK79SMkjPnRLlbBILW?= =?us-ascii?q?s1h5ZFFYMpBgJ2UoLd94R2uaEsPDha++/kYqaT/73ZDdJ7wVJ3lc8sMpvnv/AU?= =?us-ascii?q?MPa41v0tnRmDRxCUcS3e3M9VPrzLonpR5f0rxU9IwK0ewrD5OnREmLx9BFrBM6?= =?us-ascii?q?nk6rgbwsBRbu60Qqm0yIQAvb9xEMZ4HFaPqUTbZLwbW9NljyPhME3xtNWqbS+V?= =?us-ascii?q?AUoIrbR3u8aVnG0FgknZ/YYp+aYfCbXXcu7iheun2HX6/lnEkA6FYMC/eNwG2t?= =?us-ascii?q?P6boTLzVlRhCIh8q3xryhQ+Vhj8hlK9PkVKsTs3cmz3fGDPIiQJnGWI3L48NV2?= =?us-ascii?q?HE7gcUmNfrceM0fZhJsYQ7GbhkJPU0YYLo6neG1ljz6dhVbtluepuww+We75Ap?= =?us-ascii?q?v3LnoNfLRe8eWXoNRn0CFtiTK8nqRKhERNPSb0ibD/n/Eru3Gmy69U4IPPLqi/?= =?us-ascii?q?/VujRuYwWl7IBkXU0ar5PeihkOgVtZ3NUMZ4GwtoLI0+UjtScPyNzW8oXiZrls?= =?us-ascii?q?fVsBWHukS9g6A0OzX7hyfC2xCSSROAPQitckrVXk62EShgdzkH3psvaeTRHbb8?= =?us-ascii?q?a2bxQ5ekwB9wXQqPHdCFFVapYK45txbs/4Gdf47eIbdszE/MW2YL+i2kRUD?= IronPort-HdrOrdr: =?us-ascii?q?A9a23=3Alq6Z5qCgSbD7B1TlHemQ55DYdb4zR+YMi2TD?= =?us-ascii?q?tnoBLSC9F/b0qynAppomPGDP4gr5NEtApTniAtjkfZq/z+8X3WB5B97LMzUO01?= =?us-ascii?q?HYTr2Kg7GD/xTQXwX69sN4kZxrarVCDrTLZmRSvILX5xaZHr8brOW6zA=3D=3D?= X-IronPort-AV: E=Sophos;i="5.88,333,1635177600"; d="scan'208";a="123671756" Received: from unknown (HELO cn.fujitsu.com) ([10.167.33.5]) by heian.cn.fujitsu.com with ESMTP; 19 Apr 2022 12:50:54 +0800 Received: from G08CNEXMBPEKD06.g08.fujitsu.local (unknown [10.167.33.206]) by cn.fujitsu.com (Postfix) with ESMTP id 0B4AC4D169EC; Tue, 19 Apr 2022 12:50:49 +0800 (CST) Received: from G08CNEXCHPEKD09.g08.fujitsu.local (10.167.33.85) by G08CNEXMBPEKD06.g08.fujitsu.local (10.167.33.206) with Microsoft SMTP Server (TLS) id 15.0.1497.23; Tue, 19 Apr 2022 12:50:47 +0800 Received: from irides.mr.mr (10.167.225.141) by G08CNEXCHPEKD09.g08.fujitsu.local (10.167.33.209) with Microsoft SMTP Server id 15.0.1497.23 via Frontend Transport; Tue, 19 Apr 2022 12:50:46 +0800 From: Shiyang Ruan To: , , , , CC: , , , , , Christoph Hellwig Subject: [PATCH v13 2/7] mm: factor helpers for memory_failure_dev_pagemap Date: Tue, 19 Apr 2022 12:50:40 +0800 Message-ID: <20220419045045.1664996-3-ruansy.fnst@fujitsu.com> X-Mailer: git-send-email 2.35.1 In-Reply-To: <20220419045045.1664996-1-ruansy.fnst@fujitsu.com> References: <20220419045045.1664996-1-ruansy.fnst@fujitsu.com> MIME-Version: 1.0 Content-Type: text/plain X-yoursite-MailScanner-ID: 0B4AC4D169EC.A6135 X-yoursite-MailScanner: Found to be clean X-yoursite-MailScanner-From: ruansy.fnst@fujitsu.com Authentication-Results: imf23.hostedemail.com; dkim=none; spf=none (imf23.hostedemail.com: domain of ruansy.fnst@fujitsu.com has no SPF policy when checking 183.91.158.132) smtp.mailfrom=ruansy.fnst@fujitsu.com; dmarc=fail reason="No valid SPF, No valid DKIM" header.from=fujitsu.com (policy=none) X-Stat-Signature: 78ar1hcm4n93yr1g7d3ums6dm3rm46ci X-Rspamd-Queue-Id: C2869140008 X-Rspamd-Server: rspam04 X-Rspam-User: X-HE-Tag: 1650343857-13976 Content-Transfer-Encoding: quoted-printable 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: memory_failure_dev_pagemap code is a bit complex before introduce RMAP feature for fsdax. So it is needed to factor some helper functions to simplify these code. Signed-off-by: Shiyang Ruan Reviewed-by: Darrick J. Wong Reviewed-by: Christoph Hellwig Reviewed-by: Dan Williams --- mm/memory-failure.c | 157 ++++++++++++++++++++++++-------------------- 1 file changed, 87 insertions(+), 70 deletions(-) diff --git a/mm/memory-failure.c b/mm/memory-failure.c index e3fbff5bd467..7c8c047bfdc8 100644 --- a/mm/memory-failure.c +++ b/mm/memory-failure.c @@ -1498,6 +1498,90 @@ static int try_to_split_thp_page(struct page *page= , const char *msg) return 0; } =20 +static void unmap_and_kill(struct list_head *to_kill, unsigned long pfn, + struct address_space *mapping, pgoff_t index, int flags) +{ + struct to_kill *tk; + unsigned long size =3D 0; + + list_for_each_entry(tk, to_kill, nd) + if (tk->size_shift) + size =3D max(size, 1UL << tk->size_shift); + + if (size) { + /* + * Unmap the largest mapping to avoid breaking up device-dax + * mappings which are constant size. The actual size of the + * mapping being torn down is communicated in siginfo, see + * kill_proc() + */ + loff_t start =3D (index << PAGE_SHIFT) & ~(size - 1); + + unmap_mapping_range(mapping, start, size, 0); + } + + kill_procs(to_kill, flags & MF_MUST_KILL, false, pfn, flags); +} + +static int mf_generic_kill_procs(unsigned long long pfn, int flags, + struct dev_pagemap *pgmap) +{ + struct page *page =3D pfn_to_page(pfn); + LIST_HEAD(to_kill); + dax_entry_t cookie; + int rc =3D 0; + + /* + * Pages instantiated by device-dax (not filesystem-dax) + * may be compound pages. + */ + page =3D compound_head(page); + + /* + * Prevent the inode from being freed while we are interrogating + * the address_space, typically this would be handled by + * lock_page(), but dax pages do not use the page lock. This + * also prevents changes to the mapping of this pfn until + * poison signaling is complete. + */ + cookie =3D dax_lock_page(page); + if (!cookie) + return -EBUSY; + + if (hwpoison_filter(page)) { + rc =3D -EOPNOTSUPP; + goto unlock; + } + + if (pgmap->type =3D=3D MEMORY_DEVICE_PRIVATE) { + /* + * TODO: Handle HMM pages which may need coordination + * with device-side memory. + */ + return -EBUSY; + } + + /* + * 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 + * different physical page at a given virtual address, so all + * userspace consumption of ZONE_DEVICE memory necessitates + * SIGBUS (i.e. MF_MUST_KILL) + */ + flags |=3D MF_ACTION_REQUIRED | MF_MUST_KILL; + collect_procs(page, &to_kill, true); + + unmap_and_kill(&to_kill, pfn, page->mapping, page->index, flags); +unlock: + dax_unlock_page(page, cookie); + return rc; +} + /* * Called from hugetlb code with hugetlb_lock held. * @@ -1644,12 +1728,8 @@ static int memory_failure_dev_pagemap(unsigned lon= g pfn, int flags, struct dev_pagemap *pgmap) { struct page *page =3D pfn_to_page(pfn); - unsigned long size =3D 0; - struct to_kill *tk; LIST_HEAD(tokill); - int rc =3D -EBUSY; - loff_t start; - dax_entry_t cookie; + int rc =3D -ENXIO; =20 if (flags & MF_COUNT_INCREASED) /* @@ -1658,73 +1738,10 @@ static int memory_failure_dev_pagemap(unsigned lo= ng pfn, int flags, put_page(page); =20 /* device metadata space is not recoverable */ - if (!pgmap_pfn_valid(pgmap, pfn)) { - rc =3D -ENXIO; - goto out; - } - - /* - * Pages instantiated by device-dax (not filesystem-dax) - * may be compound pages. - */ - page =3D compound_head(page); - - /* - * Prevent the inode from being freed while we are interrogating - * the address_space, typically this would be handled by - * lock_page(), but dax pages do not use the page lock. This - * also prevents changes to the mapping of this pfn until - * poison signaling is complete. - */ - cookie =3D dax_lock_page(page); - if (!cookie) + if (!pgmap_pfn_valid(pgmap, pfn)) goto out; =20 - if (hwpoison_filter(page)) { - rc =3D -EOPNOTSUPP; - goto unlock; - } - - if (pgmap->type =3D=3D 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 - * different physical page at a given virtual address, so all - * userspace consumption of ZONE_DEVICE memory necessitates - * SIGBUS (i.e. MF_MUST_KILL) - */ - flags |=3D MF_ACTION_REQUIRED | MF_MUST_KILL; - collect_procs(page, &tokill, true); - - list_for_each_entry(tk, &tokill, nd) - if (tk->size_shift) - size =3D max(size, 1UL << tk->size_shift); - if (size) { - /* - * Unmap the largest mapping to avoid breaking up - * device-dax mappings which are constant size. The - * actual size of the mapping being torn down is - * communicated in siginfo, see kill_proc() - */ - start =3D (page->index << PAGE_SHIFT) & ~(size - 1); - unmap_mapping_range(page->mapping, start, size, 0); - } - kill_procs(&tokill, true, false, pfn, flags); - rc =3D 0; -unlock: - dax_unlock_page(page, cookie); + rc =3D mf_generic_kill_procs(pfn, flags, pgmap); out: /* drop pgmap ref acquired in caller */ put_dev_pagemap(pgmap); --=20 2.35.1