From patchwork Wed Jun 24 17:52:40 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Catalin Marinas X-Patchwork-Id: 11623965 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 08A3D1392 for ; Wed, 24 Jun 2020 17:53:44 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id D466E2077D for ; Wed, 24 Jun 2020 17:53:43 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org D466E2077D Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=arm.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=owner-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix) id 54BA46B0037; Wed, 24 Jun 2020 13:53:39 -0400 (EDT) Delivered-To: linux-mm-outgoing@kvack.org Received: by kanga.kvack.org (Postfix, from userid 40) id 4D6F66B0055; Wed, 24 Jun 2020 13:53:39 -0400 (EDT) X-Original-To: int-list-linux-mm@kvack.org X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 3EB696B005A; Wed, 24 Jun 2020 13:53:39 -0400 (EDT) X-Original-To: linux-mm@kvack.org X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0114.hostedemail.com [216.40.44.114]) by kanga.kvack.org (Postfix) with ESMTP id 225466B0037 for ; Wed, 24 Jun 2020 13:53:39 -0400 (EDT) Received: from smtpin29.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay04.hostedemail.com (Postfix) with ESMTP id B70A91EE6 for ; Wed, 24 Jun 2020 17:53:38 +0000 (UTC) X-FDA: 76964852916.29.arch95_1c0c52026e46 Received: from filter.hostedemail.com (10.5.16.251.rfc1918.com [10.5.16.251]) by smtpin29.hostedemail.com (Postfix) with ESMTP id 90F7018086CD2 for ; Wed, 24 Jun 2020 17:53:38 +0000 (UTC) X-Spam-Summary: 1,0,0,f452e953105b65ba,d41d8cd98f00b204,srs0=u3t/=af=arm.com=catalin.marinas@kernel.org,,RULES_HIT:41:355:379:541:800:960:966:973:981:988:989:1260:1311:1314:1345:1359:1431:1437:1515:1535:1543:1711:1730:1747:1777:1792:2196:2199:2393:2553:2559:2562:2730:3138:3139:3140:3141:3142:3354:3865:3867:3868:3870:3871:3872:4321:4385:4605:5007:6261:6742:7576:10004:11026:11232:11473:11658:11914:12043:12291:12296:12297:12438:12517:12519:12555:12679:12986:13180:13229:13894:14096:14181:14394:14721:21080:21230:21324:21451:21611:21627:21990:30012:30051:30054:30069:30075:30090,0,RBL:198.145.29.99:@kernel.org:.lbl8.mailshell.net-62.2.0.100 64.100.201.201;04yg9difxhou437pn8xpjheop6c4ayprdp6p1cwgeq73e7fh595hufoj9hhgij1.d9mmdeuc87m3of7p1pu8dif835cqnzafhucr7hntiq9o5wfrk85ehccxstbb4c4.6-lbl8.mailshell.net-223.238.255.100,CacheIP:none,Bayesian:0.5,0.5,0.5,Netcheck:none,DomainCache:0,MSF:not bulk,SPF:fp,MSBL:0,DNSBL:neutral,Custom_rules:0:0:0,LFtime:24,LUA_SUMMARY:none X-HE-Tag: arch95_1c0c52026e46 X-Filterd-Recvd-Size: 5100 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by imf32.hostedemail.com (Postfix) with ESMTP for ; Wed, 24 Jun 2020 17:53:37 +0000 (UTC) Received: from localhost.localdomain (unknown [2.26.170.173]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 14E0B207DD; Wed, 24 Jun 2020 17:53:34 +0000 (UTC) From: Catalin Marinas To: linux-arm-kernel@lists.infradead.org Cc: linux-mm@kvack.org, linux-arch@vger.kernel.org, Will Deacon , Dave P Martin , Vincenzo Frascino , Szabolcs Nagy , Kevin Brodsky , Andrey Konovalov , Peter Collingbourne , Andrew Morton , Steven Price Subject: [PATCH v5 21/25] mm: Add arch hooks for saving/restoring tags Date: Wed, 24 Jun 2020 18:52:40 +0100 Message-Id: <20200624175244.25837-22-catalin.marinas@arm.com> X-Mailer: git-send-email 2.20.1 In-Reply-To: <20200624175244.25837-1-catalin.marinas@arm.com> References: <20200624175244.25837-1-catalin.marinas@arm.com> MIME-Version: 1.0 X-Rspamd-Queue-Id: 90F7018086CD2 X-Spamd-Result: default: False [0.00 / 100.00] X-Rspamd-Server: rspam03 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: From: Steven Price Arm's Memory Tagging Extension (MTE) adds some metadata (tags) to every physical page, when swapping pages out to disk it is necessary to save these tags, and later restore them when reading the pages back. Add some hooks along with dummy implementations to enable the arch code to handle this. Three new hooks are added to the swap code: * arch_prepare_to_swap() and * arch_swap_invalidate_page() / arch_swap_invalidate_area(). One new hook is added to shmem: * arch_swap_restore_tags() Signed-off-by: Steven Price [catalin.marinas@arm.com: add unlock_page() on the error path] Signed-off-by: Catalin Marinas Cc: Andrew Morton Acked-by: Andrew Morton --- Notes: New in v4. include/linux/pgtable.h | 23 +++++++++++++++++++++++ mm/page_io.c | 10 ++++++++++ mm/shmem.c | 6 ++++++ mm/swapfile.c | 2 ++ 4 files changed, 41 insertions(+) diff --git a/include/linux/pgtable.h b/include/linux/pgtable.h index 56c1e8eb7bb0..5053d84ece04 100644 --- a/include/linux/pgtable.h +++ b/include/linux/pgtable.h @@ -631,6 +631,29 @@ static inline int arch_unmap_one(struct mm_struct *mm, } #endif +#ifndef __HAVE_ARCH_PREPARE_TO_SWAP +static inline int arch_prepare_to_swap(struct page *page) +{ + return 0; +} +#endif + +#ifndef __HAVE_ARCH_SWAP_INVALIDATE +static inline void arch_swap_invalidate_page(int type, pgoff_t offset) +{ +} + +static inline void arch_swap_invalidate_area(int type) +{ +} +#endif + +#ifndef __HAVE_ARCH_SWAP_RESTORE_TAGS +static inline void arch_swap_restore_tags(swp_entry_t entry, struct page *page) +{ +} +#endif + #ifndef __HAVE_ARCH_PGD_OFFSET_GATE #define pgd_offset_gate(mm, addr) pgd_offset(mm, addr) #endif diff --git a/mm/page_io.c b/mm/page_io.c index e8726f3e3820..9f3835161002 100644 --- a/mm/page_io.c +++ b/mm/page_io.c @@ -252,6 +252,16 @@ int swap_writepage(struct page *page, struct writeback_control *wbc) unlock_page(page); goto out; } + /* + * Arch code may have to preserve more data than just the page + * contents, e.g. memory tags. + */ + ret = arch_prepare_to_swap(page); + if (ret) { + set_page_dirty(page); + unlock_page(page); + goto out; + } if (frontswap_store(page) == 0) { set_page_writeback(page); unlock_page(page); diff --git a/mm/shmem.c b/mm/shmem.c index dacee627dae6..6cf6a1ed3d1c 100644 --- a/mm/shmem.c +++ b/mm/shmem.c @@ -1673,6 +1673,12 @@ static int shmem_swapin_page(struct inode *inode, pgoff_t index, } wait_on_page_writeback(page); + /* + * Some architectures may have to restore extra metadata to the + * physical page after reading from swap. + */ + arch_swap_restore_tags(swap, page); + if (shmem_should_replace_page(page, gfp)) { error = shmem_replace_page(&page, gfp, info, index); if (error) diff --git a/mm/swapfile.c b/mm/swapfile.c index 987276c557d1..b7a3ed45e606 100644 --- a/mm/swapfile.c +++ b/mm/swapfile.c @@ -716,6 +716,7 @@ static void swap_range_free(struct swap_info_struct *si, unsigned long offset, else swap_slot_free_notify = NULL; while (offset <= end) { + arch_swap_invalidate_page(si->type, offset); frontswap_invalidate_page(si->type, offset); if (swap_slot_free_notify) swap_slot_free_notify(si->bdev, offset); @@ -2675,6 +2676,7 @@ SYSCALL_DEFINE1(swapoff, const char __user *, specialfile) frontswap_map = frontswap_map_get(p); spin_unlock(&p->lock); spin_unlock(&swap_lock); + arch_swap_invalidate_area(p->type); frontswap_invalidate_area(p->type); frontswap_map_set(p, NULL); mutex_unlock(&swapon_mutex);