From mboxrd@z Thu Jan 1 00:00:00 1970 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 kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by smtp.lore.kernel.org (Postfix) with ESMTP id 83FBBC3064D for ; Tue, 2 Jul 2024 07:18:42 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id 05E0E6B0099; Tue, 2 Jul 2024 03:18:42 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 00D516B009B; Tue, 2 Jul 2024 03:18:41 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id DF08D6B009C; Tue, 2 Jul 2024 03:18:41 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (smtprelay0016.hostedemail.com [216.40.44.16]) by kanga.kvack.org (Postfix) with ESMTP id BB93E6B0099 for ; Tue, 2 Jul 2024 03:18:41 -0400 (EDT) Received: from smtpin14.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay07.hostedemail.com (Postfix) with ESMTP id 36FB4161FBD for ; Tue, 2 Jul 2024 07:18:41 +0000 (UTC) X-FDA: 82293960042.14.92BB2EB Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.129.124]) by imf17.hostedemail.com (Postfix) with ESMTP id D14F140008 for ; Tue, 2 Jul 2024 07:18:37 +0000 (UTC) Authentication-Results: imf17.hostedemail.com; dkim=pass header.d=redhat.com header.s=mimecast20190719 header.b=XEB5pWJO; spf=pass (imf17.hostedemail.com: domain of david@redhat.com designates 170.10.129.124 as permitted sender) smtp.mailfrom=david@redhat.com; dmarc=pass (policy=none) header.from=redhat.com ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=hostedemail.com; s=arc-20220608; t=1719904695; h=from:from:sender:reply-to:subject:subject:date:date: message-id:message-id:to:to:cc:cc:mime-version:mime-version: content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references:dkim-signature; bh=jooiWfPemUvMpiImGZEPJDFdWpBVTUluLJM85HVIgf8=; b=FGeA2yFRSZgv92Ca4pRt7LZ9ZKqGcdeJv9S/6VapBu6Hh/J2UImSZJjO98o6FLTiH1bNem atQrphddl9Wj9aVMc+Qkm+xz+qwml7C1AJ5rQE0/hr8JgexAHve2Ehyqj37IYHvAT2t8bx nFd6J5b17r8ZlnPutvMqXhOn0FCD080= ARC-Seal: i=1; s=arc-20220608; d=hostedemail.com; t=1719904695; a=rsa-sha256; cv=none; b=pRB7Wr79IusLUEhgpMsn6+B7DRzAlCKLxCEEXO3ZcjL8EEI4FiWO4H+CP93FbDeT3b3W84 uhvUSxR/Pi6mG49pMHzKoI+C4SKfZrQb3UNj1x4uo6Mt05nup4Xrjwb3D1JWRu2HslZZYs deE1inIfopcJBdKyZAdZKG3mxUTLdvE= ARC-Authentication-Results: i=1; imf17.hostedemail.com; dkim=pass header.d=redhat.com header.s=mimecast20190719 header.b=XEB5pWJO; spf=pass (imf17.hostedemail.com: domain of david@redhat.com designates 170.10.129.124 as permitted sender) smtp.mailfrom=david@redhat.com; dmarc=pass (policy=none) header.from=redhat.com DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1719904717; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references:autocrypt:autocrypt; bh=jooiWfPemUvMpiImGZEPJDFdWpBVTUluLJM85HVIgf8=; b=XEB5pWJOeziKV1Fu5nrDQHOy4fmzpteXdROksIMfYkmpRMBYlxY56R8Qo4k5yHa5UwBvwO qxiEKdhuHye6fSI0kPjQFbJFitEUoCqEmWk47mw8ZFsrtr1a66fOUPZkL5radZOhXAyo0Z SVWRFAK3Fsk/TXvb6PM6g6uyGgcjvdI= Received: from mail-wm1-f72.google.com (mail-wm1-f72.google.com [209.85.128.72]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.3, cipher=TLS_AES_256_GCM_SHA384) id us-mta-477-vzbNd1R9OaaNS_2NtcBx5A-1; Tue, 02 Jul 2024 03:18:35 -0400 X-MC-Unique: vzbNd1R9OaaNS_2NtcBx5A-1 Received: by mail-wm1-f72.google.com with SMTP id 5b1f17b1804b1-4257f95fe85so13650745e9.1 for ; Tue, 02 Jul 2024 00:18:35 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1719904714; x=1720509514; h=content-transfer-encoding:in-reply-to:organization:autocrypt :content-language:from:references:cc:to:subject:user-agent :mime-version:date:message-id:x-gm-message-state:from:to:cc:subject :date:message-id:reply-to; bh=jooiWfPemUvMpiImGZEPJDFdWpBVTUluLJM85HVIgf8=; b=lltx7CXFjNZ9tyfPQ6lF/q889w4E+xQ1WogGkigJWjy8CwiOSbk5aUhC05B9y9SNC/ FOyuVSvTjYzzzYNAZbk/P8x7iaUUcxVQXaSYuAoMF0oyE28Tm51Hw15M4FmIPGXAZz75 5VHvMmVArrSGI/P9h/qOTDhuJrArwhI9Wnw93PteSzUsX6WV6qSBDHckbIS2hl/kb7zL PuqHUVnkOsFHUO0/+qSk8jlKUOFBROWf5BhhmDzgvKgLnuki5bIbk4kNaQyaDe6j69BS 0JdHwsvwjMc0doK3uITxCKyReEWxwCDvin9HfyAkZyULYFiwHvOXrfp6a3sPvCABTRAT RVnw== X-Forwarded-Encrypted: i=1; AJvYcCX76NhNe2cKppAEoqq7SIUoKs3OKcPDv8H50FIpMt+F7ru5TD7be5OV5F5kKLmZjof73z1wIqLFS45NxRaey1JU9qA= X-Gm-Message-State: AOJu0YylkhjvJS+4t6BAJCvWL1FzCM1Ic1saWIPDuk4nnTtojQk4l7tY gH/h8kSr+t4VcRm3o6hN324M1Ebsa7l5ksGw3aPylI8Fd2AfMSP+VLU+F5Z3PoCNx5+NMflzKWY tEl2WDivtRM7h7SJmrOpHRojesvqNAuwaqZoVpv3jzEODjzL9 X-Received: by 2002:a05:600c:181b:b0:421:7bed:5274 with SMTP id 5b1f17b1804b1-4257a02f7f0mr56194015e9.10.1719904714131; Tue, 02 Jul 2024 00:18:34 -0700 (PDT) X-Google-Smtp-Source: AGHT+IEzz5o3kOQcATmNnqgXuFo5zFXlMg5tD+q0qWYrXcGunrf20m6/A/WfizHYhPadayXK53FB3w== X-Received: by 2002:a05:600c:181b:b0:421:7bed:5274 with SMTP id 5b1f17b1804b1-4257a02f7f0mr56193815e9.10.1719904713708; Tue, 02 Jul 2024 00:18:33 -0700 (PDT) Received: from ?IPV6:2003:cb:c739:2400:78ac:64bb:a39e:2578? (p200300cbc739240078ac64bba39e2578.dip0.t-ipconnect.de. [2003:cb:c739:2400:78ac:64bb:a39e:2578]) by smtp.gmail.com with ESMTPSA id 5b1f17b1804b1-42578578b69sm133608745e9.42.2024.07.02.00.18.32 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Tue, 02 Jul 2024 00:18:33 -0700 (PDT) Message-ID: Date: Tue, 2 Jul 2024 09:18:31 +0200 MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH 06/13] mm/memory: Add dax_insert_pfn To: Alistair Popple , dan.j.williams@intel.com, vishal.l.verma@intel.com, dave.jiang@intel.com, logang@deltatee.com, bhelgaas@google.com, jack@suse.cz, jgg@ziepe.ca Cc: catalin.marinas@arm.com, will@kernel.org, mpe@ellerman.id.au, npiggin@gmail.com, dave.hansen@linux.intel.com, ira.weiny@intel.com, willy@infradead.org, djwong@kernel.org, tytso@mit.edu, linmiaohe@huawei.com, peterx@redhat.com, linux-doc@vger.kernel.org, linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linuxppc-dev@lists.ozlabs.org, nvdimm@lists.linux.dev, linux-cxl@vger.kernel.org, linux-fsdevel@vger.kernel.org, linux-mm@kvack.org, linux-ext4@vger.kernel.org, linux-xfs@vger.kernel.org, jhubbard@nvidia.com, hch@lst.de, david@fromorbit.com References: <50013c1ee52b5bb1213571bff66780568455f54c.1719386613.git-series.apopple@nvidia.com> From: David Hildenbrand Autocrypt: addr=david@redhat.com; keydata= xsFNBFXLn5EBEAC+zYvAFJxCBY9Tr1xZgcESmxVNI/0ffzE/ZQOiHJl6mGkmA1R7/uUpiCjJ dBrn+lhhOYjjNefFQou6478faXE6o2AhmebqT4KiQoUQFV4R7y1KMEKoSyy8hQaK1umALTdL QZLQMzNE74ap+GDK0wnacPQFpcG1AE9RMq3aeErY5tujekBS32jfC/7AnH7I0v1v1TbbK3Gp XNeiN4QroO+5qaSr0ID2sz5jtBLRb15RMre27E1ImpaIv2Jw8NJgW0k/D1RyKCwaTsgRdwuK Kx/Y91XuSBdz0uOyU/S8kM1+ag0wvsGlpBVxRR/xw/E8M7TEwuCZQArqqTCmkG6HGcXFT0V9 PXFNNgV5jXMQRwU0O/ztJIQqsE5LsUomE//bLwzj9IVsaQpKDqW6TAPjcdBDPLHvriq7kGjt WhVhdl0qEYB8lkBEU7V2Yb+SYhmhpDrti9Fq1EsmhiHSkxJcGREoMK/63r9WLZYI3+4W2rAc UucZa4OT27U5ZISjNg3Ev0rxU5UH2/pT4wJCfxwocmqaRr6UYmrtZmND89X0KigoFD/XSeVv jwBRNjPAubK9/k5NoRrYqztM9W6sJqrH8+UWZ1Idd/DdmogJh0gNC0+N42Za9yBRURfIdKSb B3JfpUqcWwE7vUaYrHG1nw54pLUoPG6sAA7Mehl3nd4pZUALHwARAQABzSREYXZpZCBIaWxk ZW5icmFuZCA8ZGF2aWRAcmVkaGF0LmNvbT7CwZgEEwEIAEICGwMGCwkIBwMCBhUIAgkKCwQW AgMBAh4BAheAAhkBFiEEG9nKrXNcTDpGDfzKTd4Q9wD/g1oFAl8Ox4kFCRKpKXgACgkQTd4Q 9wD/g1oHcA//a6Tj7SBNjFNM1iNhWUo1lxAja0lpSodSnB2g4FCZ4R61SBR4l/psBL73xktp rDHrx4aSpwkRP6Epu6mLvhlfjmkRG4OynJ5HG1gfv7RJJfnUdUM1z5kdS8JBrOhMJS2c/gPf wv1TGRq2XdMPnfY2o0CxRqpcLkx4vBODvJGl2mQyJF/gPepdDfcT8/PY9BJ7FL6Hrq1gnAo4 3Iv9qV0JiT2wmZciNyYQhmA1V6dyTRiQ4YAc31zOo2IM+xisPzeSHgw3ONY/XhYvfZ9r7W1l pNQdc2G+o4Di9NPFHQQhDw3YTRR1opJaTlRDzxYxzU6ZnUUBghxt9cwUWTpfCktkMZiPSDGd KgQBjnweV2jw9UOTxjb4LXqDjmSNkjDdQUOU69jGMUXgihvo4zhYcMX8F5gWdRtMR7DzW/YE BgVcyxNkMIXoY1aYj6npHYiNQesQlqjU6azjbH70/SXKM5tNRplgW8TNprMDuntdvV9wNkFs 9TyM02V5aWxFfI42+aivc4KEw69SE9KXwC7FSf5wXzuTot97N9Phj/Z3+jx443jo2NR34XgF 89cct7wJMjOF7bBefo0fPPZQuIma0Zym71cP61OP/i11ahNye6HGKfxGCOcs5wW9kRQEk8P9 M/k2wt3mt/fCQnuP/mWutNPt95w9wSsUyATLmtNrwccz63XOwU0EVcufkQEQAOfX3n0g0fZz Bgm/S2zF/kxQKCEKP8ID+Vz8sy2GpDvveBq4H2Y34XWsT1zLJdvqPI4af4ZSMxuerWjXbVWb T6d4odQIG0fKx4F8NccDqbgHeZRNajXeeJ3R7gAzvWvQNLz4piHrO/B4tf8svmRBL0ZB5P5A 2uhdwLU3NZuK22zpNn4is87BPWF8HhY0L5fafgDMOqnf4guJVJPYNPhUFzXUbPqOKOkL8ojk CXxkOFHAbjstSK5Ca3fKquY3rdX3DNo+EL7FvAiw1mUtS+5GeYE+RMnDCsVFm/C7kY8c2d0G NWkB9pJM5+mnIoFNxy7YBcldYATVeOHoY4LyaUWNnAvFYWp08dHWfZo9WCiJMuTfgtH9tc75 7QanMVdPt6fDK8UUXIBLQ2TWr/sQKE9xtFuEmoQGlE1l6bGaDnnMLcYu+Asp3kDT0w4zYGsx 5r6XQVRH4+5N6eHZiaeYtFOujp5n+pjBaQK7wUUjDilPQ5QMzIuCL4YjVoylWiBNknvQWBXS lQCWmavOT9sttGQXdPCC5ynI+1ymZC1ORZKANLnRAb0NH/UCzcsstw2TAkFnMEbo9Zu9w7Kv AxBQXWeXhJI9XQssfrf4Gusdqx8nPEpfOqCtbbwJMATbHyqLt7/oz/5deGuwxgb65pWIzufa N7eop7uh+6bezi+rugUI+w6DABEBAAHCwXwEGAEIACYCGwwWIQQb2cqtc1xMOkYN/MpN3hD3 AP+DWgUCXw7HsgUJEqkpoQAKCRBN3hD3AP+DWrrpD/4qS3dyVRxDcDHIlmguXjC1Q5tZTwNB boaBTPHSy/Nksu0eY7x6HfQJ3xajVH32Ms6t1trDQmPx2iP5+7iDsb7OKAb5eOS8h+BEBDeq 3ecsQDv0fFJOA9ag5O3LLNk+3x3q7e0uo06XMaY7UHS341ozXUUI7wC7iKfoUTv03iO9El5f XpNMx/YrIMduZ2+nd9Di7o5+KIwlb2mAB9sTNHdMrXesX8eBL6T9b+MZJk+mZuPxKNVfEQMQ a5SxUEADIPQTPNvBewdeI80yeOCrN+Zzwy/Mrx9EPeu59Y5vSJOx/z6OUImD/GhX7Xvkt3kq Er5KTrJz3++B6SH9pum9PuoE/k+nntJkNMmQpR4MCBaV/J9gIOPGodDKnjdng+mXliF3Ptu6 3oxc2RCyGzTlxyMwuc2U5Q7KtUNTdDe8T0uE+9b8BLMVQDDfJjqY0VVqSUwImzTDLX9S4g/8 kC4HRcclk8hpyhY2jKGluZO0awwTIMgVEzmTyBphDg/Gx7dZU1Xf8HFuE+UZ5UDHDTnwgv7E th6RC9+WrhDNspZ9fJjKWRbveQgUFCpe1sa77LAw+XFrKmBHXp9ZVIe90RMe2tRL06BGiRZr jPrnvUsUUsjRoRNJjKKA/REq+sAnhkNPPZ/NNMjaZ5b8Tovi8C0tmxiCHaQYqj7G2rgnT0kt WNyWQQ== Organization: Red Hat In-Reply-To: <50013c1ee52b5bb1213571bff66780568455f54c.1719386613.git-series.apopple@nvidia.com> X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: redhat.com Content-Language: en-US Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit X-Stat-Signature: t7wdg6kojzpbej5d98r4r5qqqo7xmqw7 X-Rspamd-Queue-Id: D14F140008 X-Rspam-User: X-Rspamd-Server: rspam08 X-HE-Tag: 1719904717-312379 X-HE-Meta: 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 lX+eo05e 64wgLC4t8da8R4kF4zZ+KYLRyCKc0XoOlqXWN7lESprWS5y/wXg+4wLBzCXUiBrocczM02LBcmkNEp18IlLKhZzjvN0Qg2CxrFqC1Yr6Nv4+vV+E8r1Hduf5y29gFiuUtu5qdzwOtCikjznNYxhWgoKSmTOKSGihEfirfLTODIColvz8yLqtWNFOouCEDpZF44jD1YG6dl1aY8jm41o9Ajf/LV3tjiZv1XlwHfzVjoGeP4UFfRiCxDORpmV0DJ4jyxnyXxVS/B8Xyp2y/rNDLfuos0yR97+fwZgLDQp+znw5WH/WHjL82PJ0hr5bQzd2OE+bTleaIzClljkb2KF8eMzB8S7znwTU5zrTuCrd/P23eP+i/cWqa7XI6SDOrsXcfDXZgNO3Kp8qTK2ZXy3iZPYojT5eDY5uGpQIzF1h+4g87rE1xuqrMUOeHntp3NsY/eqWZ 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: List-Subscribe: List-Unsubscribe: On 27.06.24 02:54, Alistair Popple wrote: > Currently to map a DAX page the DAX driver calls vmf_insert_pfn. This > creates a special devmap PTE entry for the pfn but does not take a > reference on the underlying struct page for the mapping. This is > because DAX page refcounts are treated specially, as indicated by the > presence of a devmap entry. > > To allow DAX page refcounts to be managed the same as normal page > refcounts introduce dax_insert_pfn. This will take a reference on the > underlying page much the same as vmf_insert_page, except it also > permits upgrading an existing mapping to be writable if > requested/possible. We have this comparably nasty vmf_insert_mixed() that FS dax abused to insert into !VM_MIXED VMAs. Is that abuse now stopping and are there maybe ways to get rid of vmf_insert_mixed()? -- Cheers, David / dhildenb