From patchwork Tue Jul 26 16:18:50 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Muhammad Usama Anjum X-Patchwork-Id: 594206 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 B0D35C00144 for ; Tue, 26 Jul 2022 16:21:04 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S239297AbiGZQVD (ORCPT ); Tue, 26 Jul 2022 12:21:03 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:35972 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S237717AbiGZQU4 (ORCPT ); Tue, 26 Jul 2022 12:20:56 -0400 Received: from madras.collabora.co.uk (madras.collabora.co.uk [46.235.227.172]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 153F4255A5; Tue, 26 Jul 2022 09:20:55 -0700 (PDT) Received: from localhost.localdomain (unknown [203.135.47.243]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (4096 bits) server-digest SHA256) (No client certificate requested) (Authenticated sender: usama.anjum) by madras.collabora.co.uk (Postfix) with ESMTPSA id 2411966015A9; Tue, 26 Jul 2022 17:20:43 +0100 (BST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=collabora.com; s=mail; t=1658852453; bh=2XJezlM2O6mq/j4/cdoFLK6TcWCjkGUL5ahOSzikQrE=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=DD6J0sFg1PTj3EJZLhlR7/+xNSPOMV69E8RiZxrn74CZeVGkI1SS9LFPtILfRDyrk 11uiDC8ef3j1vxs48UbEniz5rg2s16ZSakUvXHCwQPj6PHAIqXq1JPuW3w4eTQNj38 t5UULnJkkP+JggGTRXQocJv0Io551fmgt8od018KD4nwFm9HaJKsH/uwQ1wFtppoJT 3aJL7gEcWUzBy8OF5PtHKMP4/UMaxaeLhaiCbyqUYPPGtVHIhbUiYoBlYHjyVXTw8b 8+nmpQNtCRINSJ/4NuPtr/XvaeR54EonTNG/2iAYqMhj+oYJePSZH0GEbs/cNAACym IBWWCckKRLDLw== From: Muhammad Usama Anjum To: Jonathan Corbet , Andy Lutomirski , Thomas Gleixner , Ingo Molnar , Borislav Petkov , Dave Hansen , x86@kernel.org (maintainer:X86 ARCHITECTURE (32-BIT AND 64-BIT)), "H. Peter Anvin" , Arnd Bergmann , Andrew Morton , Peter Zijlstra , Arnaldo Carvalho de Melo , Mark Rutland , Alexander Shishkin , Jiri Olsa , Namhyung Kim , Shuah Khan , linux-doc@vger.kernel.org (open list:DOCUMENTATION), linux-kernel@vger.kernel.org (open list), linux-fsdevel@vger.kernel.org (open list:PROC FILESYSTEM), linux-api@vger.kernel.org (open list:ABI/API), linux-arch@vger.kernel.org (open list:GENERIC INCLUDE/ASM HEADER FILES), linux-mm@kvack.org (open list:MEMORY MANAGEMENT), linux-perf-users@vger.kernel.org (open list:PERFORMANCE EVENTS SUBSYSTEM), linux-kselftest@vger.kernel.org (open list:KERNEL SELFTEST FRAMEWORK), krisman@collabora.com Cc: Muhammad Usama Anjum , kernel@collabora.com Subject: [PATCH 1/5] fs/proc/task_mmu: make functions global to be used in other files Date: Tue, 26 Jul 2022 21:18:50 +0500 Message-Id: <20220726161854.276359-2-usama.anjum@collabora.com> X-Mailer: git-send-email 2.30.2 In-Reply-To: <20220726161854.276359-1-usama.anjum@collabora.com> References: <20220726161854.276359-1-usama.anjum@collabora.com> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-kselftest@vger.kernel.org Update the clear_soft_dirty() and clear_soft_dirty_pmd() to optionally clear and return the status if page is dirty. Signed-off-by: Muhammad Usama Anjum --- fs/proc/task_mmu.c | 84 +-------------------------------- include/linux/mm_inline.h | 99 +++++++++++++++++++++++++++++++++++++++ 2 files changed, 101 insertions(+), 82 deletions(-) diff --git a/fs/proc/task_mmu.c b/fs/proc/task_mmu.c index f8cd58846a28..94d5761cc369 100644 --- a/fs/proc/task_mmu.c +++ b/fs/proc/task_mmu.c @@ -1076,86 +1076,6 @@ struct clear_refs_private { enum clear_refs_types type; }; -#ifdef CONFIG_MEM_SOFT_DIRTY - -static inline bool pte_is_pinned(struct vm_area_struct *vma, unsigned long addr, pte_t pte) -{ - struct page *page; - - if (!pte_write(pte)) - return false; - if (!is_cow_mapping(vma->vm_flags)) - return false; - if (likely(!test_bit(MMF_HAS_PINNED, &vma->vm_mm->flags))) - return false; - page = vm_normal_page(vma, addr, pte); - if (!page) - return false; - return page_maybe_dma_pinned(page); -} - -static inline void clear_soft_dirty(struct vm_area_struct *vma, - unsigned long addr, pte_t *pte) -{ - /* - * The soft-dirty tracker uses #PF-s to catch writes - * to pages, so write-protect the pte as well. See the - * Documentation/admin-guide/mm/soft-dirty.rst for full description - * of how soft-dirty works. - */ - pte_t ptent = *pte; - - if (pte_present(ptent)) { - pte_t old_pte; - - if (pte_is_pinned(vma, addr, ptent)) - return; - old_pte = ptep_modify_prot_start(vma, addr, pte); - ptent = pte_wrprotect(old_pte); - ptent = pte_clear_soft_dirty(ptent); - ptep_modify_prot_commit(vma, addr, pte, old_pte, ptent); - } else if (is_swap_pte(ptent)) { - ptent = pte_swp_clear_soft_dirty(ptent); - set_pte_at(vma->vm_mm, addr, pte, ptent); - } -} -#else -static inline void clear_soft_dirty(struct vm_area_struct *vma, - unsigned long addr, pte_t *pte) -{ -} -#endif - -#if defined(CONFIG_MEM_SOFT_DIRTY) && defined(CONFIG_TRANSPARENT_HUGEPAGE) -static inline void clear_soft_dirty_pmd(struct vm_area_struct *vma, - unsigned long addr, pmd_t *pmdp) -{ - pmd_t old, pmd = *pmdp; - - if (pmd_present(pmd)) { - /* See comment in change_huge_pmd() */ - old = pmdp_invalidate(vma, addr, pmdp); - if (pmd_dirty(old)) - pmd = pmd_mkdirty(pmd); - if (pmd_young(old)) - pmd = pmd_mkyoung(pmd); - - pmd = pmd_wrprotect(pmd); - pmd = pmd_clear_soft_dirty(pmd); - - set_pmd_at(vma->vm_mm, addr, pmdp, pmd); - } else if (is_migration_entry(pmd_to_swp_entry(pmd))) { - pmd = pmd_swp_clear_soft_dirty(pmd); - set_pmd_at(vma->vm_mm, addr, pmdp, pmd); - } -} -#else -static inline void clear_soft_dirty_pmd(struct vm_area_struct *vma, - unsigned long addr, pmd_t *pmdp) -{ -} -#endif - static int clear_refs_pte_range(pmd_t *pmd, unsigned long addr, unsigned long end, struct mm_walk *walk) { @@ -1168,7 +1088,7 @@ static int clear_refs_pte_range(pmd_t *pmd, unsigned long addr, ptl = pmd_trans_huge_lock(pmd, vma); if (ptl) { if (cp->type == CLEAR_REFS_SOFT_DIRTY) { - clear_soft_dirty_pmd(vma, addr, pmd); + check_soft_dirty_pmd(vma, addr, pmd, true); goto out; } @@ -1194,7 +1114,7 @@ static int clear_refs_pte_range(pmd_t *pmd, unsigned long addr, ptent = *pte; if (cp->type == CLEAR_REFS_SOFT_DIRTY) { - clear_soft_dirty(vma, addr, pte); + check_soft_dirty(vma, addr, pte, true); continue; } diff --git a/include/linux/mm_inline.h b/include/linux/mm_inline.h index 7b25b53c474a..65014c347a94 100644 --- a/include/linux/mm_inline.h +++ b/include/linux/mm_inline.h @@ -360,4 +360,103 @@ pte_install_uffd_wp_if_needed(struct vm_area_struct *vma, unsigned long addr, #endif } +#ifdef CONFIG_MEM_SOFT_DIRTY +static inline bool pte_is_pinned(struct vm_area_struct *vma, unsigned long addr, pte_t pte) +{ + struct page *page; + + if (!pte_write(pte)) + return false; + if (!is_cow_mapping(vma->vm_flags)) + return false; + if (likely(!test_bit(MMF_HAS_PINNED, &vma->vm_mm->flags))) + return false; + page = vm_normal_page(vma, addr, pte); + if (!page) + return false; + return page_maybe_dma_pinned(page); +} + +static inline bool check_soft_dirty(struct vm_area_struct *vma, + unsigned long addr, pte_t *pte, bool clear) +{ + /* + * The soft-dirty tracker uses #PF-s to catch writes + * to pages, so write-protect the pte as well. See the + * Documentation/admin-guide/mm/soft-dirty.rst for full description + * of how soft-dirty works. + */ + pte_t ptent = *pte; + int dirty = 0; + + if (pte_present(ptent)) { + pte_t old_pte; + + dirty = pte_soft_dirty(ptent); + + if (dirty && clear && !pte_is_pinned(vma, addr, ptent)) { + old_pte = ptep_modify_prot_start(vma, addr, pte); + ptent = pte_wrprotect(old_pte); + ptent = pte_clear_soft_dirty(ptent); + ptep_modify_prot_commit(vma, addr, pte, old_pte, ptent); + } + } else if (is_swap_pte(ptent)) { + dirty = pte_swp_soft_dirty(ptent); + + if (dirty && clear) { + ptent = pte_swp_clear_soft_dirty(ptent); + set_pte_at(vma->vm_mm, addr, pte, ptent); + } + } + + return !!dirty; +} +#else +static inline bool check_soft_dirty(struct vm_area_struct *vma, + unsigned long addr, pte_t *pte, bool clear) +{ + return false; +} +#endif + +#if defined(CONFIG_MEM_SOFT_DIRTY) && defined(CONFIG_TRANSPARENT_HUGEPAGE) +static inline bool check_soft_dirty_pmd(struct vm_area_struct *vma, + unsigned long addr, pmd_t *pmdp, bool clear) +{ + pmd_t old, pmd = *pmdp; + int dirty = 0; + + if (pmd_present(pmd)) { + dirty = pmd_soft_dirty(pmd); + if (dirty && clear) { + /* See comment in change_huge_pmd() */ + old = pmdp_invalidate(vma, addr, pmdp); + if (pmd_dirty(old)) + pmd = pmd_mkdirty(pmd); + if (pmd_young(old)) + pmd = pmd_mkyoung(pmd); + + pmd = pmd_wrprotect(pmd); + pmd = pmd_clear_soft_dirty(pmd); + + set_pmd_at(vma->vm_mm, addr, pmdp, pmd); + } + } else if (is_migration_entry(pmd_to_swp_entry(pmd))) { + dirty = pmd_swp_soft_dirty(pmd); + + if (dirty && clear) { + pmd = pmd_swp_clear_soft_dirty(pmd); + set_pmd_at(vma->vm_mm, addr, pmdp, pmd); + } + } + return !!dirty; +} +#else +static inline bool check_soft_dirty_pmd(struct vm_area_struct *vma, + unsigned long addr, pmd_t *pmdp, bool clear) +{ + return false; +} +#endif + #endif