From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-alma10-1.taild15c8.ts.net [100.103.45.18]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 4543D3B05A2; Wed, 29 Jul 2026 16:49:50 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=100.103.45.18 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1785343791; cv=none; b=n+iL+zZ2DUkbcE+zolUl58rluCbd+OWx8ghDbRLHfruwjMzpErUFpqFWzOTp67brlDBMh8/IpPswqsIlovcXqTapx6XZ42MEonUHkMWqaGssGggkobIUBUqnvUfHlA91DeqTSl0L7I958ClSnhRiX00SryZ0nj9w53AMEQhtY24= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1785343791; c=relaxed/simple; bh=2t5Mr+R+1YvTkz9Ej+HDVNRXrsa9Y+YAQK2UREEyZVU=; h=From:Date:Subject:MIME-Version:Content-Type:Message-Id:References: In-Reply-To:To:Cc; b=IxGePDnQQCfqe8zVqHZQ35ld5pF7XqxjVB8ZGyj7oNDEtPvCCv4bZpx0itLQBLDREVVEIAsG/s6tN/0G5ZcM9TTvcnwOzRFHCHnvZ9EGCszfV3acguXZazteHJViX1p4CIbi/+RDS8y1ux4M0X2RKrILaFdmEbfkT06zyg9Hhyc= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=UZW4rZyB; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="UZW4rZyB" Received: by smtp.kernel.org (Postfix) with ESMTPSA id B6EE21F000E9; Wed, 29 Jul 2026 16:49:43 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1785343790; bh=3AnDXjTfE+xQ+f/ssW4LV7/F/4k8NafgCiuZeEmWgjk=; h=From:Date:Subject:References:In-Reply-To:To:Cc; b=UZW4rZyBFtK+wt1THkIJxDf0KJRLDUfHY6Td2SkZznQ/VaTeeNPWJ3wO3U0cbCep5 yUSNfarHWui0tFh3ExN/gtvwMdscWKUUlcWpwHwAEKE+uQv4dGCMrYqNhWI44WzQYr xns4uSV626T/j/q+oeO3YFfcHW2SlYjhGGCs3xQg8OrCB+z1dUpGcNIt0smRDIk6HO 602TE8XD+fJt+6XICek+xasZcgrAMdqAO0ceE/BLgICuji4H+Eh+P9YtLHqf8YJC8u N67mNeZKbOq23ViE+JYs9uo+CXOe4xS9XZdQfVuCLnyhahpSCrEE8R7x0WC4uZrnIZ ObzVJ3GTETDIg== From: "Lorenzo Stoakes (ARM)" Date: Wed, 29 Jul 2026 17:48:40 +0100 Subject: [PATCH v3 05/15] mm: introduce and use vma_filebacked_address() Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 7bit Message-Id: <20260729-b4-scalable-cow-virt-pgoff-v3-5-e8ecfefea812@kernel.org> References: <20260729-b4-scalable-cow-virt-pgoff-v3-0-e8ecfefea812@kernel.org> In-Reply-To: <20260729-b4-scalable-cow-virt-pgoff-v3-0-e8ecfefea812@kernel.org> To: Andrew Morton , David Hildenbrand , "Liam R. Howlett" , Vlastimil Babka , Mike Rapoport , Suren Baghdasaryan , Michal Hocko , Jann Horn , Pedro Falcato , "Matthew Wilcox (Oracle)" , Jan Kara , Miaohe Lin , Naoya Horiguchi , Rik van Riel , Harry Yoo , Lance Yang , Kees Cook , Zi Yan , Baolin Wang , Nico Pache , Ryan Roberts , Dev Jain , Barry Song , Usama Arif , Matthew Brost , Joshua Hahn , Rakie Kim , Byungchul Park , Gregory Price , Ying Huang , Alistair Popple , Peter Xu , Xu Xin , Chengming Zhou , Arnd Bergmann , Greg Kroah-Hartman Cc: "Lorenzo Stoakes (ARM)" , linux-mm@kvack.org, linux-kernel@vger.kernel.org, linux-fsdevel@vger.kernel.org, linux-kselftest@vger.kernel.org X-Mailer: b4 0.15.2 X-Developer-Signature: v=1; a=openpgp-sha256; l=4872; i=ljs@kernel.org; h=from:subject:message-id; bh=2t5Mr+R+1YvTkz9Ej+HDVNRXrsa9Y+YAQK2UREEyZVU=; b=owGbwMvMwCV2fu7ZrsZH9SKMp9WSGLKy9H5sVEjI4ry+rvqR/BF2zY0GNmF9lntStlrISS6ey x7GvCqlo5SFQYyLQVZMkeX5F/H9QSJh8zov+LvBzGFlAhnCwMUpABPZ+ZLhn1lQ/tmWn+5fohmu q7hUKvuVMc7I3eh2rDMqXutq2Oni9YwMe7YsnPGrRuP4H8nJUzl+reTVu/Ts5OZ+3c6Z4UH7W/7 P4wAA X-Developer-Key: i=ljs@kernel.org; a=openpgp; fpr=E7F417BF5214569E89D04F46CF9DCD8A81E27F14 In cases where we know that the VMA is file-backed, use vma_filebacked_address() rather than vma_address(). This lays the foundation for using the anonymous page offset via vma_anon_address(). Also add an assert to ensure that the VMA whose address is required is not anonymous. No functional change intended. Signed-off-by: Lorenzo Stoakes (ARM) --- mm/internal.h | 18 ++++++++++++++++++ mm/memory-failure.c | 4 ++-- mm/page_vma_mapped.c | 6 +++++- mm/rmap.c | 10 ++++++---- 4 files changed, 31 insertions(+), 7 deletions(-) diff --git a/mm/internal.h b/mm/internal.h index 0d11eb8e615f..920872904bda 100644 --- a/mm/internal.h +++ b/mm/internal.h @@ -1025,6 +1025,24 @@ static inline unsigned long __vma_address(const struct vm_area_struct *vma, return address; } +/** + * vma_filebacked_address - Find the virtual address a file-backed page range is + * mapped at. + * @vma: The vma which maps this object. + * @pgoff: The page offset within its object. + * @nr_pages: The number of pages to consider. + * + * Returns: If any page in this range is mapped by this VMA, return the first + * address where any of these pages appear. Otherwise, return -EFAULT. + */ +static inline unsigned long vma_filebacked_address(const struct vm_area_struct *vma, + pgoff_t pgoff, unsigned long nr_pages) +{ + VM_WARN_ON_ONCE(vma_is_anonymous(vma)); + + return __vma_address(vma, pgoff, vma_start_pgoff(vma), nr_pages); +} + /** * vma_address - Find the virtual address a page range is mapped at. * @vma: The vma which maps this object. diff --git a/mm/memory-failure.c b/mm/memory-failure.c index aaf14608b30e..a8b03e2920ba 100644 --- a/mm/memory-failure.c +++ b/mm/memory-failure.c @@ -620,7 +620,7 @@ static void add_to_kill_fsdax(struct task_struct *tsk, const struct page *p, struct vm_area_struct *vma, struct list_head *to_kill, pgoff_t pgoff) { - unsigned long addr = vma_address(vma, pgoff, 1); + unsigned long addr = vma_filebacked_address(vma, pgoff, 1); __add_to_kill(tsk, p, vma, to_kill, addr); } @@ -2265,7 +2265,7 @@ static void add_to_kill_pgoff(struct task_struct *tsk, } /* Check for pgoff not backed by struct page */ - tk->addr = vma_address(vma, pgoff, 1); + tk->addr = vma_filebacked_address(vma, pgoff, 1); tk->size_shift = PAGE_SHIFT; if (tk->addr == -EFAULT) diff --git a/mm/page_vma_mapped.c b/mm/page_vma_mapped.c index d7670ba4147b..081e483cc7bf 100644 --- a/mm/page_vma_mapped.c +++ b/mm/page_vma_mapped.c @@ -356,6 +356,7 @@ unsigned long page_mapped_in_vma(const struct page *page, struct vm_area_struct *vma) { const struct folio *folio = page_folio(page); + const pgoff_t pgoff = page_pgoff(folio, page); struct page_vma_mapped_walk pvmw = { .pfn = page_to_pfn(page), .nr_pages = 1, @@ -363,7 +364,10 @@ unsigned long page_mapped_in_vma(const struct page *page, .flags = PVMW_SYNC, }; - pvmw.address = vma_address(vma, page_pgoff(folio, page), 1); + if (folio_test_anon(folio)) + pvmw.address = vma_address(vma, pgoff, 1); + else + pvmw.address = vma_filebacked_address(vma, pgoff, 1); if (pvmw.address == -EFAULT) goto out; if (!page_vma_mapped_walk(&pvmw)) diff --git a/mm/rmap.c b/mm/rmap.c index ad820fe86f7d..5798427d007f 100644 --- a/mm/rmap.c +++ b/mm/rmap.c @@ -865,14 +865,15 @@ unsigned long page_address_in_vma(const struct folio *folio, if (!vma->anon_vma || !anon_vma || vma->anon_vma->root != anon_vma->root) return -EFAULT; + /* KSM folios don't reach here because of the !anon_vma check */ + return vma_address(vma, page_pgoff(folio, page), 1); } else if (!vma->vm_file) { return -EFAULT; } else if (vma->vm_file->f_mapping != folio->mapping) { return -EFAULT; } - /* KSM folios don't reach here because of the !anon_vma check */ - return vma_address(vma, page_pgoff(folio, page), 1); + return vma_filebacked_address(vma, page_pgoff(folio, page), 1); } /* @@ -1321,7 +1322,7 @@ int pfn_mkclean_range(unsigned long pfn, unsigned long nr_pages, pgoff_t pgoff, if (invalid_mkclean_vma(vma, NULL)) return 0; - pvmw.address = vma_address(vma, pgoff, nr_pages); + pvmw.address = vma_filebacked_address(vma, pgoff, nr_pages); VM_BUG_ON_VMA(pvmw.address == -EFAULT, vma); return page_vma_mkclean_one(&pvmw); @@ -3100,7 +3101,8 @@ static void __rmap_walk_file(struct folio *folio, struct address_space *mapping, } lookup: mapping_rmap_tree_foreach(vma, mapping, pgoff_start, pgoff_end) { - unsigned long address = vma_address(vma, pgoff_start, nr_pages); + unsigned long address = vma_filebacked_address(vma, pgoff_start, + nr_pages); VM_BUG_ON_VMA(address == -EFAULT, vma); cond_resched(); -- 2.55.0