From patchwork Wed Feb 2 14:33:02 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Muchun Song X-Patchwork-Id: 12733080 Received: from mail-pl1-f172.google.com (mail-pl1-f172.google.com [209.85.214.172]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 35C8E2F29 for ; Wed, 2 Feb 2022 14:34:25 +0000 (UTC) Received: by mail-pl1-f172.google.com with SMTP id j16so18443420plx.4 for ; Wed, 02 Feb 2022 06:34:25 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=bytedance-com.20210112.gappssmtp.com; s=20210112; h=from:to:cc:subject:date:message-id:in-reply-to:references :mime-version:content-transfer-encoding; bh=gpzrZ3UL1NNnyKoM6H+wPQyBpC1NKCVMLCNYU70r2B0=; b=FP6uo0J+XGUKU/YjQtKSKRs4FCJsisKC/hx8Y5wk6tYiUm9x62TdWeN3eu9+XCbJ1T TbJ16jy2DDntW86mp/sgYUpOOoGM5nlDBwUdy22h9MAmHMjRI0elhETTyVqpGzEgkHLZ Amj6MaV9Qz8yIzmzZqDG+kqBaTuwIfrJgFh+n6YxIPB2UkmIVsx2Rh9lrv9c4GRca5au mia8XrC7PMNdb8X6VPlKHtUztzZlvGKzqqXwjAXp+wfogI4Bs/9xJRbFy6cgBidDMhNw SSMl2asEvsdP1oodO1jj7EY/xuSnAsGCMdXd7EfYxgPrjWGi6QUaCnO4/rnadNS6lvow LU7Q== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:from:to:cc:subject:date:message-id:in-reply-to :references:mime-version:content-transfer-encoding; bh=gpzrZ3UL1NNnyKoM6H+wPQyBpC1NKCVMLCNYU70r2B0=; b=La1yblzJW9JIzgFr7mC7Eh+v/Z0gv11FQuCm+66BPb7+k888EVoHvNxaVxm9HK7qrn oCFogjMEzUxWkJwoEhsapXBwqAujrrXr1GH7DXMDzrlOLzcSqk3j3lwVJBvrwAot+T2R xlyMD92x7t8u86kDKKq7SZlVAgxw9+8IgVFlMatKOY+Tx66bw1OZ/sEN7xD7qW/Ak9zL IJcrlTK2r136ufCBxMHCydAPQquVf2FUdA5RR2H3apMcAhOK6v+mLZ/Ih1ZR/URPSB+N BSq8y4suQbOm9tq2le82yN1r3TvtriIwZf8Ya7qn92bNT9EkoYlOpnDkAzJRfOqncv1z Bq5w== X-Gm-Message-State: AOAM531qV3cPB4IPij0RCdwE9Qs8dc7qIZsGLJ5J9TQzKRsvQYhq3Ta3 KJg+KnHI80owUYt2yOeOa1Ue2Q== X-Google-Smtp-Source: ABdhPJx1R74lXZlM/Cxg6cfKwxH1FD4NPDRYz154Mh+OGethIUvLeH+xKUNAPo6FkkGG3/cUrVF6pQ== X-Received: by 2002:a17:902:c412:: with SMTP id k18mr30904459plk.142.1643812465457; Wed, 02 Feb 2022 06:34:25 -0800 (PST) Received: from FVFYT0MHHV2J.tiktokcdn.com ([139.177.225.241]) by smtp.gmail.com with ESMTPSA id s9sm29079268pgm.76.2022.02.02.06.34.18 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Wed, 02 Feb 2022 06:34:25 -0800 (PST) From: Muchun Song To: dan.j.williams@intel.com, willy@infradead.org, jack@suse.cz, viro@zeniv.linux.org.uk, akpm@linux-foundation.org, apopple@nvidia.com, shy828301@gmail.com, rcampbell@nvidia.com, hughd@google.com, xiyuyang19@fudan.edu.cn, kirill.shutemov@linux.intel.com, zwisler@kernel.org, hch@infradead.org Cc: linux-fsdevel@vger.kernel.org, nvdimm@lists.linux.dev, linux-kernel@vger.kernel.org, linux-mm@kvack.org, duanxiongchun@bytedance.com, Muchun Song Subject: [PATCH v2 1/6] mm: rmap: fix cache flush on THP pages Date: Wed, 2 Feb 2022 22:33:02 +0800 Message-Id: <20220202143307.96282-2-songmuchun@bytedance.com> X-Mailer: git-send-email 2.32.0 (Apple Git-132) In-Reply-To: <20220202143307.96282-1-songmuchun@bytedance.com> References: <20220202143307.96282-1-songmuchun@bytedance.com> Precedence: bulk X-Mailing-List: nvdimm@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 The flush_cache_page() only remove a PAGE_SIZE sized range from the cache. However, it does not cover the full pages in a THP except a head page. Replace it with flush_cache_range() to fix this issue. At least, no problems were found due to this. Maybe because the architectures that have virtual indexed caches is less. Fixes: f27176cfc363 ("mm: convert page_mkclean_one() to use page_vma_mapped_walk()") Signed-off-by: Muchun Song Reviewed-by: Yang Shi Reviewed-by: Jan Kara --- mm/rmap.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/mm/rmap.c b/mm/rmap.c index b0fd9dc19eba..0ba12dc9fae3 100644 --- a/mm/rmap.c +++ b/mm/rmap.c @@ -974,7 +974,8 @@ static bool page_mkclean_one(struct page *page, struct vm_area_struct *vma, if (!pmd_dirty(*pmd) && !pmd_write(*pmd)) continue; - flush_cache_page(vma, address, page_to_pfn(page)); + flush_cache_range(vma, address, + address + HPAGE_PMD_SIZE); entry = pmdp_invalidate(vma, address, pmd); entry = pmd_wrprotect(entry); entry = pmd_mkclean(entry); From patchwork Wed Feb 2 14:33:03 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Muchun Song X-Patchwork-Id: 12733081 Received: from mail-pj1-f44.google.com (mail-pj1-f44.google.com [209.85.216.44]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id E59642F29 for ; Wed, 2 Feb 2022 14:34:32 +0000 (UTC) Received: by mail-pj1-f44.google.com with SMTP id g15-20020a17090a67cf00b001b7d5b6bedaso6184568pjm.4 for ; Wed, 02 Feb 2022 06:34:32 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=bytedance-com.20210112.gappssmtp.com; s=20210112; h=from:to:cc:subject:date:message-id:in-reply-to:references :mime-version:content-transfer-encoding; bh=yqTwEL7kOTcKChIBcjkLKs2qIde8K14LqGVT2DBRTU0=; b=QfoqDLtleFoLTKKXN2gEfiVcozG97ChIFEO+Dxb9kfB8mws46ckDiFZ0spHu+3Ckwi KQZam58ZAHqgcYKidzpFN3iPnYbSqMyyJG9+H9OJMKcVySUshYFShTfVPilrnyzKLSYH /hwxBMauDgvjBwXaDv+t8Aigdr4S4kh8m6NusA04i61YrBQTjYU+aXUCrcvJKRfVAtto sw938xa5LtXWuBW9vMuJyLDJ7JhQtLB6VO31Lkk4zgYI1K22xsLAs86nIFN1bdsqem9D b9A0oRcRgZgOiBmtV/hB8lrUnmP7ugc5phBXv7BZKIExxz7n+Io5ja4QbCqxemwNNnNZ LTNA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:from:to:cc:subject:date:message-id:in-reply-to :references:mime-version:content-transfer-encoding; bh=yqTwEL7kOTcKChIBcjkLKs2qIde8K14LqGVT2DBRTU0=; b=eLntJ4H+bXgLYTiwcXfv2EMqu6oLQ/p8e8LzB8CrDENZuGXBHwA55z9K/BB7Cv74xV Md/osZnC54Thc4+puxwEbnXod9UfXSXcYM+YU8UQaSQubRqF7A0qoNuuhEa79UtuiW4c W7Yuicln6nIKN7VPLSkyRywEPaHRmLk0W92dqS7h6xjh/VsRaQpkSUayg3TyvCQA62Mf t/u8xCGNfL481g8gmwuFohYsipm1ATA6hGGEK0jFcPg2qDIF/1fT4wRsykjTmpIFYRB5 GVy8W0VeWzmcUPS5BrZofa1bcQEqwumLRUuvvufp96vkVmaemtJntZUJGLRgKmYAxBNe aF0w== X-Gm-Message-State: AOAM531ptmLMz/xsP/xZ30vsmHMP1AOFEBmbeDc66enbJNuZFy2T6qW9 NfF8+t8x+0auESbDzPT/jDjyHQ== X-Google-Smtp-Source: ABdhPJzSJUsu2k5lK4qLz9mFNP97HsqVWca02fgKwu6JP8Fe8B9Slwu6HkVpi8yiT/kqkiwV52Yk5Q== X-Received: by 2002:a17:90a:cc07:: with SMTP id b7mr8389698pju.43.1643812472560; Wed, 02 Feb 2022 06:34:32 -0800 (PST) Received: from FVFYT0MHHV2J.tiktokcdn.com ([139.177.225.241]) by smtp.gmail.com with ESMTPSA id s9sm29079268pgm.76.2022.02.02.06.34.25 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Wed, 02 Feb 2022 06:34:32 -0800 (PST) From: Muchun Song To: dan.j.williams@intel.com, willy@infradead.org, jack@suse.cz, viro@zeniv.linux.org.uk, akpm@linux-foundation.org, apopple@nvidia.com, shy828301@gmail.com, rcampbell@nvidia.com, hughd@google.com, xiyuyang19@fudan.edu.cn, kirill.shutemov@linux.intel.com, zwisler@kernel.org, hch@infradead.org Cc: linux-fsdevel@vger.kernel.org, nvdimm@lists.linux.dev, linux-kernel@vger.kernel.org, linux-mm@kvack.org, duanxiongchun@bytedance.com, Muchun Song Subject: [PATCH v2 2/6] dax: fix cache flush on PMD-mapped pages Date: Wed, 2 Feb 2022 22:33:03 +0800 Message-Id: <20220202143307.96282-3-songmuchun@bytedance.com> X-Mailer: git-send-email 2.32.0 (Apple Git-132) In-Reply-To: <20220202143307.96282-1-songmuchun@bytedance.com> References: <20220202143307.96282-1-songmuchun@bytedance.com> Precedence: bulk X-Mailing-List: nvdimm@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 The flush_cache_page() only remove a PAGE_SIZE sized range from the cache. However, it does not cover the full pages in a THP except a head page. Replace it with flush_cache_range() to fix this issue. Fixes: f729c8c9b24f ("dax: wrprotect pmd_t in dax_mapping_entry_mkclean") Signed-off-by: Muchun Song Reviewed-by: Jan Kara --- fs/dax.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/fs/dax.c b/fs/dax.c index 88be1c02a151..e031e4b6c13c 100644 --- a/fs/dax.c +++ b/fs/dax.c @@ -857,7 +857,8 @@ static void dax_entry_mkclean(struct address_space *mapping, pgoff_t index, if (!pmd_dirty(*pmdp) && !pmd_write(*pmdp)) goto unlock_pmd; - flush_cache_page(vma, address, pfn); + flush_cache_range(vma, address, + address + HPAGE_PMD_SIZE); pmd = pmdp_invalidate(vma, address, pmdp); pmd = pmd_wrprotect(pmd); pmd = pmd_mkclean(pmd); From patchwork Wed Feb 2 14:33:04 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Muchun Song X-Patchwork-Id: 12733082 Received: from mail-pj1-f47.google.com (mail-pj1-f47.google.com [209.85.216.47]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 1D80C2F29 for ; Wed, 2 Feb 2022 14:34:40 +0000 (UTC) Received: by mail-pj1-f47.google.com with SMTP id cq9-20020a17090af98900b001b8262fe2d5so2157932pjb.0 for ; Wed, 02 Feb 2022 06:34:40 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=bytedance-com.20210112.gappssmtp.com; s=20210112; h=from:to:cc:subject:date:message-id:in-reply-to:references :mime-version:content-transfer-encoding; bh=CF0auyXfFKE1IEYVq03Jkg+soFc4skAhc1lxx6fAtcg=; b=zOnd2QjsWbes5CPtqMDtzwXXx4Qnh1nB96Y73gx80JMX1YjE5DYvNj1kR9Rf3wf1Px wPuL2t4JGGdjFrn3XZwBVG9F97cAQb8RsouQZBjVNVlljY0CH7I4qVCxJPzanyQSnmuI z71LOW9oAQWGsSJ1NUqzh5Vrqxv/E0Jt45Av/0yEAyBFuJciQZXRDGzQkl/3ilBDl5vR jKsqrChDzxht2TufcoW2BxuBTd7zqUeVt/m99Tym+LFF8zmYzhKc1GWZowCKaAWNH6FN Y8Sz6J6ClIh39VVIbK6GaQ6pwV6GArpJpzIClZo9pXpaDCVMFxz9DSlMeibVUkc8PRwG 9kZw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:from:to:cc:subject:date:message-id:in-reply-to :references:mime-version:content-transfer-encoding; bh=CF0auyXfFKE1IEYVq03Jkg+soFc4skAhc1lxx6fAtcg=; b=ZFdxLTdzjkNr6/4CseyHuqjz7+ZjnnBmNPx+IkX75NH59zEKaKfYKesfEVjxxY7Kmt lZhWNoLEmpbaeOfvdNjwGB4w61Qrtrjd/rGyCyL/O0TQFPNIPyxj0EGSNeLdrczsQFAW 2mFVUWZKgVulgbQY85Tb4kAzfgeGOoNPPmOPirIRJ2+841iic14vCiNKlpxCAokJOLcX y+BumsHzQgeQC+x6YrQLS3bEAchmREMomPZ6IRM3Z4RhiB08osz4FNPkC4TNqs8V9zv9 xNLwVIN4glv2lkNDJTdgWYBxs7VdwdVWplZ2TU7J42JOGYVX4u93d/6fLnpU1Cfho6H/ BKWA== X-Gm-Message-State: AOAM530S98vsq3B+F240n6d8mXiZGfPHzE2YLxRKPKGwDYKh1AP4VAtZ l+sdmFqfo0NfYBuUUnJsYAm50Q== X-Google-Smtp-Source: ABdhPJzKJWYQyKWHxR8pIvNPFkTCP1Kls8SRhFx7AdpdZ5ZMRZ5hqgrfl3+Hv7AKQVSi09LI0EwDXA== X-Received: by 2002:a17:90a:94cc:: with SMTP id j12mr8341153pjw.39.1643812479607; Wed, 02 Feb 2022 06:34:39 -0800 (PST) Received: from FVFYT0MHHV2J.tiktokcdn.com ([139.177.225.241]) by smtp.gmail.com with ESMTPSA id s9sm29079268pgm.76.2022.02.02.06.34.32 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Wed, 02 Feb 2022 06:34:39 -0800 (PST) From: Muchun Song To: dan.j.williams@intel.com, willy@infradead.org, jack@suse.cz, viro@zeniv.linux.org.uk, akpm@linux-foundation.org, apopple@nvidia.com, shy828301@gmail.com, rcampbell@nvidia.com, hughd@google.com, xiyuyang19@fudan.edu.cn, kirill.shutemov@linux.intel.com, zwisler@kernel.org, hch@infradead.org Cc: linux-fsdevel@vger.kernel.org, nvdimm@lists.linux.dev, linux-kernel@vger.kernel.org, linux-mm@kvack.org, duanxiongchun@bytedance.com, Muchun Song Subject: [PATCH v2 3/6] mm: page_vma_mapped: support checking if a pfn is mapped into a vma Date: Wed, 2 Feb 2022 22:33:04 +0800 Message-Id: <20220202143307.96282-4-songmuchun@bytedance.com> X-Mailer: git-send-email 2.32.0 (Apple Git-132) In-Reply-To: <20220202143307.96282-1-songmuchun@bytedance.com> References: <20220202143307.96282-1-songmuchun@bytedance.com> Precedence: bulk X-Mailing-List: nvdimm@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 page_vma_mapped_walk() is supposed to check if a page is mapped into a vma. However, not all page frames (e.g. PFN_DEV) have a associated struct page with it. There is going to be some duplicate codes similar with this function if someone want to check if a pfn (without a struct page) is mapped into a vma. So add support for checking if a pfn is mapped into a vma. In the next patch, the dax will use this new feature. Signed-off-by: Muchun Song --- include/linux/rmap.h | 14 ++++++++-- include/linux/swapops.h | 13 +++++++--- mm/internal.h | 28 +++++++++++++------- mm/page_vma_mapped.c | 68 +++++++++++++++++++++++++++++++------------------ 4 files changed, 83 insertions(+), 40 deletions(-) diff --git a/include/linux/rmap.h b/include/linux/rmap.h index 221c3c6438a7..78373935ad49 100644 --- a/include/linux/rmap.h +++ b/include/linux/rmap.h @@ -204,9 +204,18 @@ int make_device_exclusive_range(struct mm_struct *mm, unsigned long start, #define PVMW_SYNC (1 << 0) /* Look for migarion entries rather than present PTEs */ #define PVMW_MIGRATION (1 << 1) +/* Walk the page table by checking the pfn instead of a struct page */ +#define PVMW_PFN_WALK (1 << 2) struct page_vma_mapped_walk { - struct page *page; + union { + struct page *page; + struct { + unsigned long pfn; + unsigned int nr; + pgoff_t index; + }; + }; struct vm_area_struct *vma; unsigned long address; pmd_t *pmd; @@ -218,7 +227,8 @@ struct page_vma_mapped_walk { static inline void page_vma_mapped_walk_done(struct page_vma_mapped_walk *pvmw) { /* HugeTLB pte is set to the relevant page table entry without pte_mapped. */ - if (pvmw->pte && !PageHuge(pvmw->page)) + if (pvmw->pte && (pvmw->flags & PVMW_PFN_WALK || + !PageHuge(pvmw->page))) pte_unmap(pvmw->pte); if (pvmw->ptl) spin_unlock(pvmw->ptl); diff --git a/include/linux/swapops.h b/include/linux/swapops.h index d356ab4047f7..d28bf65fd6a5 100644 --- a/include/linux/swapops.h +++ b/include/linux/swapops.h @@ -247,17 +247,22 @@ static inline int is_writable_migration_entry(swp_entry_t entry) #endif -static inline struct page *pfn_swap_entry_to_page(swp_entry_t entry) +static inline unsigned long pfn_swap_entry_to_pfn(swp_entry_t entry) { - struct page *p = pfn_to_page(swp_offset(entry)); + unsigned long pfn = swp_offset(entry); /* * Any use of migration entries may only occur while the * corresponding page is locked */ - BUG_ON(is_migration_entry(entry) && !PageLocked(p)); + BUG_ON(is_migration_entry(entry) && !PageLocked(pfn_to_page(pfn))); + + return pfn; +} - return p; +static inline struct page *pfn_swap_entry_to_page(swp_entry_t entry) +{ + return pfn_to_page(pfn_swap_entry_to_pfn(entry)); } /* diff --git a/mm/internal.h b/mm/internal.h index deb9bda18e59..5458cd08df33 100644 --- a/mm/internal.h +++ b/mm/internal.h @@ -478,25 +478,35 @@ vma_address(struct page *page, struct vm_area_struct *vma) } /* - * Then at what user virtual address will none of the page be found in vma? - * Assumes that vma_address() already returned a good starting address. - * If page is a compound head, the entire compound page is considered. + * Return the end of user virtual address at the specific offset within + * a vma. */ static inline unsigned long -vma_address_end(struct page *page, struct vm_area_struct *vma) +vma_pgoff_address_end(pgoff_t pgoff, unsigned long nr_pages, + struct vm_area_struct *vma) { - pgoff_t pgoff; - unsigned long address; + unsigned long address = vma->vm_start; - VM_BUG_ON_PAGE(PageKsm(page), page); /* KSM page->index unusable */ - pgoff = page_to_pgoff(page) + compound_nr(page); - address = vma->vm_start + ((pgoff - vma->vm_pgoff) << PAGE_SHIFT); + address += (pgoff + nr_pages - vma->vm_pgoff) << PAGE_SHIFT; /* Check for address beyond vma (or wrapped through 0?) */ if (address < vma->vm_start || address > vma->vm_end) address = vma->vm_end; return address; } +/* + * Return the end of user virtual address of a page within a vma. Assumes that + * vma_address() already returned a good starting address. If page is a compound + * head, the entire compound page is considered. + */ +static inline unsigned long +vma_address_end(struct page *page, struct vm_area_struct *vma) +{ + VM_BUG_ON_PAGE(PageKsm(page), page); /* KSM page->index unusable */ + return vma_pgoff_address_end(page_to_pgoff(page), compound_nr(page), + vma); +} + static inline struct file *maybe_unlock_mmap_for_io(struct vm_fault *vmf, struct file *fpin) { diff --git a/mm/page_vma_mapped.c b/mm/page_vma_mapped.c index f7b331081791..bd172268084f 100644 --- a/mm/page_vma_mapped.c +++ b/mm/page_vma_mapped.c @@ -53,10 +53,17 @@ static bool map_pte(struct page_vma_mapped_walk *pvmw) return true; } -static inline bool pfn_is_match(struct page *page, unsigned long pfn) +static inline bool pfn_is_match(struct page_vma_mapped_walk *pvmw, + unsigned long pfn) { - unsigned long page_pfn = page_to_pfn(page); + struct page *page; + unsigned long page_pfn; + if (pvmw->flags & PVMW_PFN_WALK) + return pfn >= pvmw->pfn && pfn - pvmw->pfn < pvmw->nr; + + page = pvmw->page; + page_pfn = page_to_pfn(page); /* normal page and hugetlbfs page */ if (!PageTransCompound(page) || PageHuge(page)) return page_pfn == pfn; @@ -116,7 +123,7 @@ static bool check_pte(struct page_vma_mapped_walk *pvmw) pfn = pte_pfn(*pvmw->pte); } - return pfn_is_match(pvmw->page, pfn); + return pfn_is_match(pvmw, pfn); } static void step_forward(struct page_vma_mapped_walk *pvmw, unsigned long size) @@ -127,24 +134,24 @@ static void step_forward(struct page_vma_mapped_walk *pvmw, unsigned long size) } /** - * page_vma_mapped_walk - check if @pvmw->page is mapped in @pvmw->vma at - * @pvmw->address - * @pvmw: pointer to struct page_vma_mapped_walk. page, vma, address and flags - * must be set. pmd, pte and ptl must be NULL. + * page_vma_mapped_walk - check if @pvmw->page or @pvmw->pfn is mapped in + * @pvmw->vma at @pvmw->address + * @pvmw: pointer to struct page_vma_mapped_walk. page (or pfn and nr and + * index), vma, address and flags must be set. pmd, pte and ptl must be NULL. * - * Returns true if the page is mapped in the vma. @pvmw->pmd and @pvmw->pte point - * to relevant page table entries. @pvmw->ptl is locked. @pvmw->address is - * adjusted if needed (for PTE-mapped THPs). + * Returns true if the page or pfn is mapped in the vma. @pvmw->pmd and + * @pvmw->pte point to relevant page table entries. @pvmw->ptl is locked. + * @pvmw->address is adjusted if needed (for PTE-mapped THPs). * * If @pvmw->pmd is set but @pvmw->pte is not, you have found PMD-mapped page - * (usually THP). For PTE-mapped THP, you should run page_vma_mapped_walk() in - * a loop to find all PTEs that map the THP. + * (usually THP or Huge DEVMAP). For PMD-mapped page, you should run + * page_vma_mapped_walk() in a loop to find all PTEs that map the huge page. * * For HugeTLB pages, @pvmw->pte is set to the relevant page table entry * regardless of which page table level the page is mapped at. @pvmw->pmd is * NULL. * - * Returns false if there are no more page table entries for the page in + * Returns false if there are no more page table entries for the page or pfn in * the vma. @pvmw->ptl is unlocked and @pvmw->pte is unmapped. * * If you need to stop the walk before page_vma_mapped_walk() returned false, @@ -153,8 +160,9 @@ static void step_forward(struct page_vma_mapped_walk *pvmw, unsigned long size) bool page_vma_mapped_walk(struct page_vma_mapped_walk *pvmw) { struct mm_struct *mm = pvmw->vma->vm_mm; - struct page *page = pvmw->page; + struct page *page = NULL; unsigned long end; + unsigned long pfn; pgd_t *pgd; p4d_t *p4d; pud_t *pud; @@ -164,7 +172,11 @@ bool page_vma_mapped_walk(struct page_vma_mapped_walk *pvmw) if (pvmw->pmd && !pvmw->pte) return not_found(pvmw); - if (unlikely(PageHuge(page))) { + if (!(pvmw->flags & PVMW_PFN_WALK)) + page = pvmw->page; + pfn = page ? page_to_pfn(page) : pvmw->pfn; + + if (unlikely(page && PageHuge(page))) { /* The only possible mapping was handled on last iteration */ if (pvmw->pte) return not_found(pvmw); @@ -187,9 +199,13 @@ bool page_vma_mapped_walk(struct page_vma_mapped_walk *pvmw) * any PageKsm page: whose page->index misleads vma_address() * and vma_address_end() to disaster. */ - end = PageTransCompound(page) ? - vma_address_end(page, pvmw->vma) : - pvmw->address + PAGE_SIZE; + if (page) + end = PageTransCompound(page) ? + vma_address_end(page, pvmw->vma) : + pvmw->address + PAGE_SIZE; + else + end = vma_pgoff_address_end(pvmw->index, pvmw->nr, pvmw->vma); + if (pvmw->pte) goto next_pte; restart: @@ -217,14 +233,14 @@ bool page_vma_mapped_walk(struct page_vma_mapped_walk *pvmw) * subsequent update. */ pmde = READ_ONCE(*pvmw->pmd); - - if (pmd_trans_huge(pmde) || is_pmd_migration_entry(pmde)) { +#ifdef CONFIG_TRANSPARENT_HUGEPAGE + if (pmd_leaf(pmde) || is_pmd_migration_entry(pmde)) { pvmw->ptl = pmd_lock(mm, pvmw->pmd); pmde = *pvmw->pmd; - if (likely(pmd_trans_huge(pmde))) { + if (likely(pmd_leaf(pmde))) { if (pvmw->flags & PVMW_MIGRATION) return not_found(pvmw); - if (pmd_page(pmde) != page) + if (pmd_pfn(pmde) != pfn) return not_found(pvmw); return true; } @@ -236,20 +252,22 @@ bool page_vma_mapped_walk(struct page_vma_mapped_walk *pvmw) return not_found(pvmw); entry = pmd_to_swp_entry(pmde); if (!is_migration_entry(entry) || - pfn_swap_entry_to_page(entry) != page) + pfn_swap_entry_to_pfn(entry) != pfn) return not_found(pvmw); return true; } /* THP pmd was split under us: handle on pte level */ spin_unlock(pvmw->ptl); pvmw->ptl = NULL; - } else if (!pmd_present(pmde)) { + } else +#endif + if (!pmd_present(pmde)) { /* * If PVMW_SYNC, take and drop THP pmd lock so that we * cannot return prematurely, while zap_huge_pmd() has * cleared *pmd but not decremented compound_mapcount(). */ - if ((pvmw->flags & PVMW_SYNC) && + if ((pvmw->flags & PVMW_SYNC) && page && PageTransCompound(page)) { spinlock_t *ptl = pmd_lock(mm, pvmw->pmd); 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Wed, 02 Feb 2022 06:34:46 -0800 (PST) From: Muchun Song To: dan.j.williams@intel.com, willy@infradead.org, jack@suse.cz, viro@zeniv.linux.org.uk, akpm@linux-foundation.org, apopple@nvidia.com, shy828301@gmail.com, rcampbell@nvidia.com, hughd@google.com, xiyuyang19@fudan.edu.cn, kirill.shutemov@linux.intel.com, zwisler@kernel.org, hch@infradead.org Cc: linux-fsdevel@vger.kernel.org, nvdimm@lists.linux.dev, linux-kernel@vger.kernel.org, linux-mm@kvack.org, duanxiongchun@bytedance.com, Muchun Song Subject: [PATCH v2 4/6] mm: rmap: introduce pfn_mkclean_range() to cleans PTEs Date: Wed, 2 Feb 2022 22:33:05 +0800 Message-Id: <20220202143307.96282-5-songmuchun@bytedance.com> X-Mailer: git-send-email 2.32.0 (Apple Git-132) In-Reply-To: <20220202143307.96282-1-songmuchun@bytedance.com> References: <20220202143307.96282-1-songmuchun@bytedance.com> Precedence: bulk X-Mailing-List: nvdimm@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 The page_mkclean_one() is supposed to be used with the pfn that has a associated struct page, but not all the pfns (e.g. DAX) have a struct page. Introduce a new function pfn_mkclean_range() to cleans the PTEs (including PMDs) mapped with range of pfns which has no struct page associated with them. This helper will be used by DAX device in the next patch to make pfns clean. Signed-off-by: Muchun Song --- include/linux/rmap.h | 3 ++ mm/internal.h | 26 ++++++++++------ mm/rmap.c | 84 +++++++++++++++++++++++++++++++++++++++++----------- 3 files changed, 86 insertions(+), 27 deletions(-) diff --git a/include/linux/rmap.h b/include/linux/rmap.h index 78373935ad49..668a1e81b442 100644 --- a/include/linux/rmap.h +++ b/include/linux/rmap.h @@ -241,6 +241,9 @@ bool page_vma_mapped_walk(struct page_vma_mapped_walk *pvmw); */ unsigned long page_address_in_vma(struct page *, struct vm_area_struct *); +int pfn_mkclean_range(unsigned long pfn, int npfn, pgoff_t pgoff, + struct vm_area_struct *vma); + /* * Cleans the PTEs of shared mappings. * (and since clean PTEs should also be readonly, write protects them too) diff --git a/mm/internal.h b/mm/internal.h index 5458cd08df33..dc71256e568f 100644 --- a/mm/internal.h +++ b/mm/internal.h @@ -449,26 +449,22 @@ extern void clear_page_mlock(struct page *page); extern pmd_t maybe_pmd_mkwrite(pmd_t pmd, struct vm_area_struct *vma); /* - * At what user virtual address is page expected in vma? - * Returns -EFAULT if all of the page is outside the range of vma. - * If page is a compound head, the entire compound page is considered. + * Return the start of user virtual address at the specific offset within + * a vma. */ static inline unsigned long -vma_address(struct page *page, struct vm_area_struct *vma) +vma_pgoff_address(pgoff_t pgoff, unsigned long nr_pages, + struct vm_area_struct *vma) { - pgoff_t pgoff; unsigned long address; - VM_BUG_ON_PAGE(PageKsm(page), page); /* KSM page->index unusable */ - pgoff = page_to_pgoff(page); if (pgoff >= vma->vm_pgoff) { address = vma->vm_start + ((pgoff - vma->vm_pgoff) << PAGE_SHIFT); /* Check for address beyond vma (or wrapped through 0?) */ if (address < vma->vm_start || address >= vma->vm_end) address = -EFAULT; - } else if (PageHead(page) && - pgoff + compound_nr(page) - 1 >= vma->vm_pgoff) { + } else if (pgoff + nr_pages - 1 >= vma->vm_pgoff) { /* Test above avoids possibility of wrap to 0 on 32-bit */ address = vma->vm_start; } else { @@ -478,6 +474,18 @@ vma_address(struct page *page, struct vm_area_struct *vma) } /* + * Return the start of user virtual address of a page within a vma. + * Returns -EFAULT if all of the page is outside the range of vma. + * If page is a compound head, the entire compound page is considered. + */ +static inline unsigned long +vma_address(struct page *page, struct vm_area_struct *vma) +{ + VM_BUG_ON_PAGE(PageKsm(page), page); /* KSM page->index unusable */ + return vma_pgoff_address(page_to_pgoff(page), compound_nr(page), vma); +} + +/* * Return the end of user virtual address at the specific offset within * a vma. */ diff --git a/mm/rmap.c b/mm/rmap.c index 0ba12dc9fae3..8f1860dc22bc 100644 --- a/mm/rmap.c +++ b/mm/rmap.c @@ -928,34 +928,33 @@ int page_referenced(struct page *page, return pra.referenced; } -static bool page_mkclean_one(struct page *page, struct vm_area_struct *vma, - unsigned long address, void *arg) +static int page_vma_mkclean_one(struct page_vma_mapped_walk *pvmw) { - struct page_vma_mapped_walk pvmw = { - .page = page, - .vma = vma, - .address = address, - .flags = PVMW_SYNC, - }; + int cleaned = 0; + struct vm_area_struct *vma = pvmw->vma; struct mmu_notifier_range range; - int *cleaned = arg; + unsigned long end; + + if (pvmw->flags & PVMW_PFN_WALK) + end = vma_pgoff_address_end(pvmw->index, pvmw->nr, vma); + else + end = vma_address_end(pvmw->page, vma); /* * We have to assume the worse case ie pmd for invalidation. Note that * the page can not be free from this function. */ - mmu_notifier_range_init(&range, MMU_NOTIFY_PROTECTION_PAGE, - 0, vma, vma->vm_mm, address, - vma_address_end(page, vma)); + mmu_notifier_range_init(&range, MMU_NOTIFY_PROTECTION_PAGE, 0, vma, + vma->vm_mm, pvmw->address, end); mmu_notifier_invalidate_range_start(&range); - while (page_vma_mapped_walk(&pvmw)) { + while (page_vma_mapped_walk(pvmw)) { int ret = 0; + unsigned long address = pvmw->address; - address = pvmw.address; - if (pvmw.pte) { + if (pvmw->pte) { pte_t entry; - pte_t *pte = pvmw.pte; + pte_t *pte = pvmw->pte; if (!pte_dirty(*pte) && !pte_write(*pte)) continue; @@ -968,7 +967,7 @@ static bool page_mkclean_one(struct page *page, struct vm_area_struct *vma, ret = 1; } else { #ifdef CONFIG_TRANSPARENT_HUGEPAGE - pmd_t *pmd = pvmw.pmd; + pmd_t *pmd = pvmw->pmd; pmd_t entry; if (!pmd_dirty(*pmd) && !pmd_write(*pmd)) @@ -995,11 +994,27 @@ static bool page_mkclean_one(struct page *page, struct vm_area_struct *vma, * See Documentation/vm/mmu_notifier.rst */ if (ret) - (*cleaned)++; + cleaned++; } mmu_notifier_invalidate_range_end(&range); + return cleaned; +} + +static bool page_mkclean_one(struct page *page, struct vm_area_struct *vma, + unsigned long address, void *arg) +{ + struct page_vma_mapped_walk pvmw = { + .page = page, + .vma = vma, + .address = address, + .flags = PVMW_SYNC, + }; + int *cleaned = arg; + + *cleaned += page_vma_mkclean_one(&pvmw); + return true; } @@ -1037,6 +1052,39 @@ int folio_mkclean(struct folio *folio) EXPORT_SYMBOL_GPL(folio_mkclean); /** + * pfn_mkclean_range - Cleans the PTEs (including PMDs) mapped with range of + * [@pfn, @pfn + @npfn) at the specific offset (@pgoff) + * within the @vma of shared mappings. And since clean PTEs + * should also be readonly, write protects them too. + * @pfn: start pfn. + * @npfn: number of physically contiguous pfns srarting with @pfn. + * @pgoff: page offset that the @pfn mapped with. + * @vma: vma that @pfn mapped within. + * + * Returns the number of cleaned PTEs (including PMDs). + */ +int pfn_mkclean_range(unsigned long pfn, int npfn, pgoff_t pgoff, + struct vm_area_struct *vma) +{ + unsigned long address = vma_pgoff_address(pgoff, npfn, vma); + struct page_vma_mapped_walk pvmw = { + .pfn = pfn, + .nr = npfn, + .index = pgoff, + .vma = vma, + .address = address, + .flags = PVMW_SYNC | PVMW_PFN_WALK, + }; + + if (invalid_mkclean_vma(vma, NULL)) + return 0; + + VM_BUG_ON_VMA(address == -EFAULT, vma); + + return page_vma_mkclean_one(&pvmw); +} + +/** * page_move_anon_rmap - move a page to our anon_vma * @page: the page to move to our anon_vma * @vma: the vma the page belongs to From patchwork Wed Feb 2 14:33:06 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Muchun Song X-Patchwork-Id: 12733084 Received: from mail-pl1-f170.google.com (mail-pl1-f170.google.com [209.85.214.170]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 048CC2F29 for ; Wed, 2 Feb 2022 14:34:54 +0000 (UTC) Received: by mail-pl1-f170.google.com with SMTP id l13so9772629plg.9 for ; Wed, 02 Feb 2022 06:34:53 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=bytedance-com.20210112.gappssmtp.com; s=20210112; h=from:to:cc:subject:date:message-id:in-reply-to:references :mime-version:content-transfer-encoding; bh=uplRDMf9P3k9aUR6OrL9VGZsCccO7/3RG36fBhJFyME=; b=kSLOTeQhvBFw7fsL96na0cRlWcVjElWVvAoseaINB/pZHqA7KWxP3av/18pkL1aF+0 MKOQJZSHRAd5a5PwAiR1h2yWe05lQOOjIoyguZQ6FRdfPhWOhYS2Q2cmjxo/HRQGt/Jy BLny0ZANjrtCry2BJhLKzk1uwsIbJqH7I0w5IgRmX7/Xh8uBWszfMynYBEc3fqos21Qu CxFcpkYtSGBHbUPVu/D5nyQUIrxpb/JUykO56+48bAqzUjS16agFbbk3P3Z3QbATWhrM WyboLCUgxUOu26c9aIeOzVgtlweBJ8PzLJ1+xwkL63Hi5ucGoWjq0bEicpnPVjxdUrpG lkKw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:from:to:cc:subject:date:message-id:in-reply-to :references:mime-version:content-transfer-encoding; bh=uplRDMf9P3k9aUR6OrL9VGZsCccO7/3RG36fBhJFyME=; b=SeySM7jEQhhBDlOCIHTKLPrpufoLyZmzu9Uh6u6yCJxO6RyQTC43Ou+sa3DfvDdEHn nIDUfg/qnsT45srcmCsMYuR5AQBZ3tiJHvbBUx49FwBAZMCNf9O5MYhpG0o/FDmN6qMe vgu+mo08Xia+VesCY85XZ8n95IeryaMIirVgamWos6Lmknw8u12jobpEdAtJSO1NCGAU w1QPl+RKHNubGChQHopn/RSN+mKoDyo8h8feiCHOE4dke2wUo1fN61gUtXtvWZibRhhl ukuFJCI5JQvbrxEjWem69a3EfKOWBLp8VoURSdA6263A+5926aVjmaHqn+Ww/DfYgwFZ MuTA== X-Gm-Message-State: AOAM5315+JMFgura7OSyTQqIgbcWqg2LYR3a3Ut4pxq89M5prQj08//B amKtcrfRSkHNBSyPwyO+3T8Hvg== X-Google-Smtp-Source: ABdhPJxYVhkrB3EfA0Rf/jBLdL6J+MWAJGy/3N8zt0fObDKgb6hfYJaRk8Ro75dji+V85rbzZGD4sA== X-Received: by 2002:a17:902:e851:: with SMTP id t17mr30063915plg.102.1643812493488; Wed, 02 Feb 2022 06:34:53 -0800 (PST) Received: from FVFYT0MHHV2J.tiktokcdn.com ([139.177.225.241]) by smtp.gmail.com with ESMTPSA id s9sm29079268pgm.76.2022.02.02.06.34.46 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Wed, 02 Feb 2022 06:34:53 -0800 (PST) From: Muchun Song To: dan.j.williams@intel.com, willy@infradead.org, jack@suse.cz, viro@zeniv.linux.org.uk, akpm@linux-foundation.org, apopple@nvidia.com, shy828301@gmail.com, rcampbell@nvidia.com, hughd@google.com, xiyuyang19@fudan.edu.cn, kirill.shutemov@linux.intel.com, zwisler@kernel.org, hch@infradead.org Cc: linux-fsdevel@vger.kernel.org, nvdimm@lists.linux.dev, linux-kernel@vger.kernel.org, linux-mm@kvack.org, duanxiongchun@bytedance.com, Muchun Song Subject: [PATCH v2 5/6] dax: fix missing writeprotect the pte entry Date: Wed, 2 Feb 2022 22:33:06 +0800 Message-Id: <20220202143307.96282-6-songmuchun@bytedance.com> X-Mailer: git-send-email 2.32.0 (Apple Git-132) In-Reply-To: <20220202143307.96282-1-songmuchun@bytedance.com> References: <20220202143307.96282-1-songmuchun@bytedance.com> Precedence: bulk X-Mailing-List: nvdimm@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Currently dax_mapping_entry_mkclean() fails to clean and write protect the pte entry within a DAX PMD entry during an *sync operation. This can result in data loss in the following sequence: 1) process A mmap write to DAX PMD, dirtying PMD radix tree entry and making the pmd entry dirty and writeable. 2) process B mmap with the @offset (e.g. 4K) and @length (e.g. 4K) write to the same file, dirtying PMD radix tree entry (already done in 1)) and making the pte entry dirty and writeable. 3) fsync, flushing out PMD data and cleaning the radix tree entry. We currently fail to mark the pte entry as clean and write protected since the vma of process B is not covered in dax_entry_mkclean(). 4) process B writes to the pte. These don't cause any page faults since the pte entry is dirty and writeable. The radix tree entry remains clean. 5) fsync, which fails to flush the dirty PMD data because the radix tree entry was clean. 6) crash - dirty data that should have been fsync'd as part of 5) could still have been in the processor cache, and is lost. Just to use pfn_mkclean_range() to clean the pfns to fix this issue. Fixes: 4b4bb46d00b3 ("dax: clear dirty entry tags on cache flush") Signed-off-by: Muchun Song --- fs/dax.c | 83 ++++++---------------------------------------------------------- 1 file changed, 7 insertions(+), 76 deletions(-) diff --git a/fs/dax.c b/fs/dax.c index e031e4b6c13c..b64ac02d55d7 100644 --- a/fs/dax.c +++ b/fs/dax.c @@ -25,6 +25,7 @@ #include #include #include +#include #include #define CREATE_TRACE_POINTS @@ -801,87 +802,17 @@ static void *dax_insert_entry(struct xa_state *xas, return entry; } -static inline -unsigned long pgoff_address(pgoff_t pgoff, struct vm_area_struct *vma) -{ - unsigned long address; - - address = vma->vm_start + ((pgoff - vma->vm_pgoff) << PAGE_SHIFT); - VM_BUG_ON_VMA(address < vma->vm_start || address >= vma->vm_end, vma); - return address; -} - /* Walk all mappings of a given index of a file and writeprotect them */ -static void dax_entry_mkclean(struct address_space *mapping, pgoff_t index, - unsigned long pfn) +static void dax_entry_mkclean(struct address_space *mapping, unsigned long pfn, + unsigned long npfn, pgoff_t start) { struct vm_area_struct *vma; - pte_t pte, *ptep = NULL; - pmd_t *pmdp = NULL; - spinlock_t *ptl; + pgoff_t end = start + npfn - 1; i_mmap_lock_read(mapping); - vma_interval_tree_foreach(vma, &mapping->i_mmap, index, index) { - struct mmu_notifier_range range; - unsigned long address; - + vma_interval_tree_foreach(vma, &mapping->i_mmap, start, end) { + pfn_mkclean_range(pfn, npfn, start, vma); cond_resched(); - - if (!(vma->vm_flags & VM_SHARED)) - continue; - - address = pgoff_address(index, vma); - - /* - * follow_invalidate_pte() will use the range to call - * mmu_notifier_invalidate_range_start() on our behalf before - * taking any lock. - */ - if (follow_invalidate_pte(vma->vm_mm, address, &range, &ptep, - &pmdp, &ptl)) - continue; - - /* - * No need to call mmu_notifier_invalidate_range() as we are - * downgrading page table protection not changing it to point - * to a new page. - * - * See Documentation/vm/mmu_notifier.rst - */ - if (pmdp) { -#ifdef CONFIG_FS_DAX_PMD - pmd_t pmd; - - if (pfn != pmd_pfn(*pmdp)) - goto unlock_pmd; - if (!pmd_dirty(*pmdp) && !pmd_write(*pmdp)) - goto unlock_pmd; - - flush_cache_range(vma, address, - address + HPAGE_PMD_SIZE); - pmd = pmdp_invalidate(vma, address, pmdp); - pmd = pmd_wrprotect(pmd); - pmd = pmd_mkclean(pmd); - set_pmd_at(vma->vm_mm, address, pmdp, pmd); -unlock_pmd: -#endif - spin_unlock(ptl); - } else { - if (pfn != pte_pfn(*ptep)) - goto unlock_pte; - if (!pte_dirty(*ptep) && !pte_write(*ptep)) - goto unlock_pte; - - flush_cache_page(vma, address, pfn); - pte = ptep_clear_flush(vma, address, ptep); - pte = pte_wrprotect(pte); - pte = pte_mkclean(pte); - set_pte_at(vma->vm_mm, address, ptep, pte); -unlock_pte: - pte_unmap_unlock(ptep, ptl); - } - - mmu_notifier_invalidate_range_end(&range); } i_mmap_unlock_read(mapping); } @@ -949,7 +880,7 @@ static int dax_writeback_one(struct xa_state *xas, struct dax_device *dax_dev, count = 1UL << dax_entry_order(entry); index = xas->xa_index & ~(count - 1); - dax_entry_mkclean(mapping, index, pfn); + dax_entry_mkclean(mapping, pfn, count, index); dax_flush(dax_dev, page_address(pfn_to_page(pfn)), count * PAGE_SIZE); /* * After we have flushed the cache, we can clear the dirty tag. There From patchwork Wed Feb 2 14:33:07 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Muchun Song X-Patchwork-Id: 12733085 Received: from mail-pf1-f179.google.com (mail-pf1-f179.google.com [209.85.210.179]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 1BBE72F29 for ; Wed, 2 Feb 2022 14:35:01 +0000 (UTC) Received: by mail-pf1-f179.google.com with SMTP id c194so6436879pfb.12 for ; Wed, 02 Feb 2022 06:35:01 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=bytedance-com.20210112.gappssmtp.com; s=20210112; h=from:to:cc:subject:date:message-id:in-reply-to:references :mime-version:content-transfer-encoding; bh=yfAXAcV/wZ+uHO6JBR1mzR4k32V5m276WxyzPLvNLTE=; b=Jtk3Kzgm/acaQdPFcEkC9Vlykmm8QQmOLbTQ0WNCe5c19+7qPERmzZTnk2K/kXPWT3 awBMTwT+IctxLSgpQTzoCPDBfv7AnZh8a7ms5e+HG/IcD4gkzcs+GVpFwq0BSaaEOBzC +Z8F1B1ZxZOxRnIMDLeurg++5JhMZLe2voq7jns4oadz++eOKm6B6z+X9URirr4NHkff oy5mB5XhSrwbAb6rAdlIm9OzVkgFJv+SE8i0xol8ijOkdIvv1Hfrr/Ck5yvb/m/I5Jrq 45/qvfmRK3Rxch2z7W9+sPNOSQH6/gz0279qxMsX6gU59wHHjcAL2zSo6NjBGpmVSnyW a01w== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:from:to:cc:subject:date:message-id:in-reply-to :references:mime-version:content-transfer-encoding; bh=yfAXAcV/wZ+uHO6JBR1mzR4k32V5m276WxyzPLvNLTE=; b=BnEQ3KNrpZjiJEyy9cBNgkwOzyCimEpwlSYPoeDNTgXLWJHuYZ8C3xxWw0lZkZXAZP bkEWDad71Ae6po76wIHrXIlxXZjGGnxc0khPSEaBmCThlMkXmCkriW8CxBNCR6tXYFDE E97EmyFo5axmddSSlV+rKekf3/6UUXjatiWGcEujgWtG6bEuVeX4y1Dvw0oxE2oWMnx8 IpQFpCs/Va1I3A/WV8HafDbZ5A9wXjnSOu1Cuy6Qo/4JI64lGxKZmJOBMl/axhJWBcwP T6IVlNqBfFDhN7YeeqSIWpe/rJGxDfanZgvc2ZdhaXa8uI/h3HN5YUpFhydVkMPyO2PQ tU/g== X-Gm-Message-State: AOAM5301+d8W/RTBJULvBLxtY9fE+bm6rRVo156I2Z3DQtLYMyYEyiW4 x3/qleoYx+KMw3eLq69izU0m4g== X-Google-Smtp-Source: ABdhPJzW7VqsfdOXDPUXv6t69WSXlrB+FLAIOju7z/IcFQKVnTEKauVXBfJqD5J3XyiRSyiWJX7H4w== X-Received: by 2002:a05:6a00:174b:: with SMTP id j11mr9475901pfc.19.1643812500607; Wed, 02 Feb 2022 06:35:00 -0800 (PST) Received: from FVFYT0MHHV2J.tiktokcdn.com ([139.177.225.241]) by smtp.gmail.com with ESMTPSA id s9sm29079268pgm.76.2022.02.02.06.34.53 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Wed, 02 Feb 2022 06:35:00 -0800 (PST) From: Muchun Song To: dan.j.williams@intel.com, willy@infradead.org, jack@suse.cz, viro@zeniv.linux.org.uk, akpm@linux-foundation.org, apopple@nvidia.com, shy828301@gmail.com, rcampbell@nvidia.com, hughd@google.com, xiyuyang19@fudan.edu.cn, kirill.shutemov@linux.intel.com, zwisler@kernel.org, hch@infradead.org Cc: linux-fsdevel@vger.kernel.org, nvdimm@lists.linux.dev, linux-kernel@vger.kernel.org, linux-mm@kvack.org, duanxiongchun@bytedance.com, Muchun Song Subject: [PATCH v2 6/6] mm: remove range parameter from follow_invalidate_pte() Date: Wed, 2 Feb 2022 22:33:07 +0800 Message-Id: <20220202143307.96282-7-songmuchun@bytedance.com> X-Mailer: git-send-email 2.32.0 (Apple Git-132) In-Reply-To: <20220202143307.96282-1-songmuchun@bytedance.com> References: <20220202143307.96282-1-songmuchun@bytedance.com> Precedence: bulk X-Mailing-List: nvdimm@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 The only user (DAX) of range parameter of follow_invalidate_pte() is gone, it safe to remove the range paramter and make it static to simlify the code. Signed-off-by: Muchun Song --- include/linux/mm.h | 3 --- mm/memory.c | 23 +++-------------------- 2 files changed, 3 insertions(+), 23 deletions(-) diff --git a/include/linux/mm.h b/include/linux/mm.h index d211a06784d5..7895b17f6847 100644 --- a/include/linux/mm.h +++ b/include/linux/mm.h @@ -1814,9 +1814,6 @@ void free_pgd_range(struct mmu_gather *tlb, unsigned long addr, unsigned long end, unsigned long floor, unsigned long ceiling); int copy_page_range(struct vm_area_struct *dst_vma, struct vm_area_struct *src_vma); -int follow_invalidate_pte(struct mm_struct *mm, unsigned long address, - struct mmu_notifier_range *range, pte_t **ptepp, - pmd_t **pmdpp, spinlock_t **ptlp); int follow_pte(struct mm_struct *mm, unsigned long address, pte_t **ptepp, spinlock_t **ptlp); int follow_pfn(struct vm_area_struct *vma, unsigned long address, diff --git a/mm/memory.c b/mm/memory.c index 514a81cdd1ae..e8ce066be5f2 100644 --- a/mm/memory.c +++ b/mm/memory.c @@ -4869,9 +4869,8 @@ int __pmd_alloc(struct mm_struct *mm, pud_t *pud, unsigned long address) } #endif /* __PAGETABLE_PMD_FOLDED */ -int follow_invalidate_pte(struct mm_struct *mm, unsigned long address, - struct mmu_notifier_range *range, pte_t **ptepp, - pmd_t **pmdpp, spinlock_t **ptlp) +static int follow_invalidate_pte(struct mm_struct *mm, unsigned long address, + pte_t **ptepp, pmd_t **pmdpp, spinlock_t **ptlp) { pgd_t *pgd; p4d_t *p4d; @@ -4898,31 +4897,17 @@ int follow_invalidate_pte(struct mm_struct *mm, unsigned long address, if (!pmdpp) goto out; - if (range) { - mmu_notifier_range_init(range, MMU_NOTIFY_CLEAR, 0, - NULL, mm, address & PMD_MASK, - (address & PMD_MASK) + PMD_SIZE); - mmu_notifier_invalidate_range_start(range); - } *ptlp = pmd_lock(mm, pmd); if (pmd_huge(*pmd)) { *pmdpp = pmd; return 0; } spin_unlock(*ptlp); - if (range) - mmu_notifier_invalidate_range_end(range); } if (pmd_none(*pmd) || unlikely(pmd_bad(*pmd))) goto out; - if (range) { - mmu_notifier_range_init(range, MMU_NOTIFY_CLEAR, 0, NULL, mm, - address & PAGE_MASK, - (address & PAGE_MASK) + PAGE_SIZE); - mmu_notifier_invalidate_range_start(range); - } ptep = pte_offset_map_lock(mm, pmd, address, ptlp); if (!pte_present(*ptep)) goto unlock; @@ -4930,8 +4915,6 @@ int follow_invalidate_pte(struct mm_struct *mm, unsigned long address, return 0; unlock: pte_unmap_unlock(ptep, *ptlp); - if (range) - mmu_notifier_invalidate_range_end(range); out: return -EINVAL; } @@ -4960,7 +4943,7 @@ int follow_invalidate_pte(struct mm_struct *mm, unsigned long address, int follow_pte(struct mm_struct *mm, unsigned long address, pte_t **ptepp, spinlock_t **ptlp) { - return follow_invalidate_pte(mm, address, NULL, ptepp, NULL, ptlp); + return follow_invalidate_pte(mm, address, ptepp, NULL, ptlp); } EXPORT_SYMBOL_GPL(follow_pte);