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 E4A9F3B14CD; Tue, 11 Aug 2026 16:19:58 +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=1786465200; cv=none; b=f3OpRtTqxuub4JtUAHsdHk3fEguu3csxq+21tLrZbd3aP27U/1CPd9nwlB2V+LzIwf/J9gjk9UqH7ECu9vfYRKAgfnqUSkNiYPBs6qTJsaq70eQ00OEvYbDUiM1Tq+mLU3IoDmbqPzSX7L9zdUTeoim+Uu25mQDipR7xET0XG7w= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1786465200; c=relaxed/simple; bh=EgPlDPoB7az0Uv1m/TPt2TlTfcV5y6OPXkHnh19meog=; h=Message-ID:Date:MIME-Version:Subject:To:Cc:References:From: In-Reply-To:Content-Type; b=TAbBKe2GQrRBCsFdohuKCe56Pv0qZ+/E2YkmVvZQsPtLHpcvzoEUKIRMg640q9DtLGMIu2rg8NJXujMq+gRmQpL6atiEVN7WaGC/JyGQlKgcQalQA99mbzVUezkkb1WNpxoE9ePZGdwOdFYs2gCdEYr20rajq/QQJU8TMJ19Cy0= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=D9zlC8Ue; 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="D9zlC8Ue" Received: by smtp.kernel.org (Postfix) with ESMTPSA id D44F91F000E9; Tue, 11 Aug 2026 16:19:33 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1786465198; bh=D7CISCZNOUacwFken/zE3V4XA36dbwptL0r4v8Me1CY=; h=Date:Subject:To:Cc:References:From:In-Reply-To; b=D9zlC8Ue7xyoRzrsbwUuTAn1JU7oiR5DVZid6WO7JwmYfxYK7juv4wK4YWA3jvPG9 fMNh6tkMCQAiV+0Zo803pEDObPx++QRzDbMTeqC8FVs213MQc6MHYwYbGM82/YGtMG tumFrAoC8OmH0ntJar3oMIJddzwnBWGwpC3au/UO2THkmABUJaTyb0scTymw68IjPu kkzGIAx14f0Jo7Xj9f/5/MjJGsLzrZgyFQOhYEJ9un76PSAbLqN1pq7gCZuqWWpzIm 6wtuElC4RxaAl6cqVD+qTUPqAZdGhDYxOoD/cQsukiy/qeg4CvEDax1X263j94k9PW qvRYNgLu9hing== Message-ID: <1d8cd29b-8a4d-454c-8dce-121b97e9d52b@kernel.org> Date: Tue, 11 Aug 2026 18:19:31 +0200 Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH v4 03/20] mm: introduce linear_anon_page_index() To: "Lorenzo Stoakes (ARM)" , Andrew Morton , "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 , Christian Borntraeger , Janosch Frank , Claudio Imbrenda , Alexander Gordeev , Gerald Schaefer , Heiko Carstens , Vasily Gorbik , Sven Schnelle , Alex Deucher , =?UTF-8?Q?Christian_K=C3=B6nig?= , David Airlie , Simona Vetter , Maarten Lankhorst , Maxime Ripard , Thomas Zimmermann , Boris Brezillon , Steven Price , Liviu Dudau , Huang Rui , Matthew Auld , =?UTF-8?Q?Thomas_Hellstr=C3=B6m?= , Rodrigo Vivi , Masami Hiramatsu , Oleg Nesterov , Peter Zijlstra , Ingo Molnar , Arnaldo Carvalho de Melo , Namhyung Kim , Mark Rutland , Alexander Shishkin , Jiri Olsa , Ian Rogers , Adrian Hunter , James Clark , Jason Gunthorpe , John Hubbard , Muchun Song , Oscar Salvador , Chris Li , Kairui Song , Kemeng Shi , Nhat Pham , Baoquan He , Youngjun Park Cc: linux-mm@kvack.org, linux-kernel@vger.kernel.org, linux-fsdevel@vger.kernel.org, linux-kselftest@vger.kernel.org, kvm@vger.kernel.org, linux-s390@vger.kernel.org, amd-gfx@lists.freedesktop.org, dri-devel@lists.freedesktop.org, intel-xe@lists.freedesktop.org, linux-perf-users@vger.kernel.org, linux-trace-kernel@vger.kernel.org References: <20260806-b4-scalable-cow-virt-pgoff-v4-0-ab318a350404@kernel.org> <20260806-b4-scalable-cow-virt-pgoff-v4-3-ab318a350404@kernel.org> From: "David Hildenbrand (Arm)" Content-Language: en-US Autocrypt: addr=david@kernel.org; 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charset=UTF-8 Content-Transfer-Encoding: 7bit On 8/6/26 22:21, Lorenzo Stoakes (ARM) wrote: > This function provides the anonymous equivalent of linear_page_index(), > instead offsetting based on the anonymous page offset of the VMA. > > It is valid only for anonymous or MAP_PRIVATE file-backed mappings, in > other words CoW mappings. > > For pure anon VMAs, this will be equal to linear_page_index(). > > Assert that both of these invariants are true In linear_anon_page_index() > and implement the algorithm in __linear_anon_page_index(). > > Note that MAP_PRIVATE-/dev/zero mappings will satisfy vma_is_anonymous() > but not fulfill this invariant, so when asserting this we check > vma->vm_file to account for this. > > We do not update callsites yet, so no functional change intended. > > Also const-ify vma_is_anonymous() to make it compatible with the > const-ified linear_anon_page_index(). > > While we're here, update linear_page_index() to be more succinct. > > VMA userland tests are also updated accordingly. > > Reviewed-by: Gregory Price (Meta) > Signed-off-by: Lorenzo Stoakes (ARM) > --- Acked-by: David Hildenbrand (Arm) -- Cheers, David