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 A7808C46CD2 for ; Tue, 30 Jan 2024 09:03:05 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id 26E716B00A2; Tue, 30 Jan 2024 04:03:05 -0500 (EST) Received: by kanga.kvack.org (Postfix, from userid 40) id 2238F6B00A7; Tue, 30 Jan 2024 04:03:05 -0500 (EST) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id EEEFE6B00A6; Tue, 30 Jan 2024 04:03:04 -0500 (EST) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (smtprelay0011.hostedemail.com [216.40.44.11]) by kanga.kvack.org (Postfix) with ESMTP id D16046B0078 for ; Tue, 30 Jan 2024 04:03:04 -0500 (EST) Received: from smtpin30.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay05.hostedemail.com (Postfix) with ESMTP id A3767407C3 for ; Tue, 30 Jan 2024 09:03:04 +0000 (UTC) X-FDA: 81735387888.30.CDB68FA Received: from mailout2.w1.samsung.com (mailout2.w1.samsung.com [210.118.77.12]) by imf08.hostedemail.com (Postfix) with ESMTP id 12D8C160017 for ; Tue, 30 Jan 2024 09:03:00 +0000 (UTC) Authentication-Results: imf08.hostedemail.com; dkim=pass header.d=samsung.com header.s=mail20170921 header.b=femepWid; dmarc=pass (policy=none) header.from=samsung.com; spf=pass (imf08.hostedemail.com: domain of a.hindborg@samsung.com designates 210.118.77.12 as permitted sender) smtp.mailfrom=a.hindborg@samsung.com ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=hostedemail.com; s=arc-20220608; t=1706605381; 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=u5skJTC1NiSxxvHS0YUB/jwBwTXaDHnBS1B0psxcAog=; b=XmbsiqTZxuANEaDrUGhMYf4hiX8H/KO+IAkc55Fh/7fF0dBPjnmbuiohGThSHrz48yikXe mdmBdGF5zQw1G74oT5f34A+HpYK/59yvE4oEcGX+IudRqkyb4aO1ifp5PqwdkbudoX0ii8 d5EjYSxFbWm++eLee8BvRl3INyYi26Y= ARC-Authentication-Results: i=1; imf08.hostedemail.com; dkim=pass header.d=samsung.com header.s=mail20170921 header.b=femepWid; dmarc=pass (policy=none) header.from=samsung.com; spf=pass (imf08.hostedemail.com: domain of a.hindborg@samsung.com designates 210.118.77.12 as permitted sender) smtp.mailfrom=a.hindborg@samsung.com ARC-Seal: i=1; s=arc-20220608; d=hostedemail.com; t=1706605381; a=rsa-sha256; cv=none; b=wIYGm3dXaBBrhQ5NDX/Ozn8t0WypH59WPmxjAEXf43dap91hJgX51hqIoGZUflhDj0pbQe WoNtIyTyi7ZKzdeyObzp2o1pZud+JKWCyFteknMti7dwGHr0WU0btXMOETrT5PLIQL2ZYd 2tfCqlKWt+UJvpVGh+AXU2KHP3RWZA4= Received: from eucas1p2.samsung.com (unknown [182.198.249.207]) by mailout2.w1.samsung.com (KnoxPortal) with ESMTP id 20240130090258euoutp0286b37a594822046baab1f9fea71914e5~vFIzJsoXi2693226932euoutp02F for ; Tue, 30 Jan 2024 09:02:58 +0000 (GMT) DKIM-Filter: OpenDKIM Filter v2.11.0 mailout2.w1.samsung.com 20240130090258euoutp0286b37a594822046baab1f9fea71914e5~vFIzJsoXi2693226932euoutp02F DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=samsung.com; s=mail20170921; t=1706605378; bh=u5skJTC1NiSxxvHS0YUB/jwBwTXaDHnBS1B0psxcAog=; h=From:To:CC:Subject:Date:In-Reply-To:References:From; b=femepWidQ6EJHN5Aj267qrGtF2Jj7X6duSAVhyRkcrvlFpZIedfxS0i9+vGOsH9mH CLvI/Rr1lyfxVC0AdGP3i5yLHHTN3/vIXPxXWveiGws8JsTewSgggmcU1ijYvcYvHc 9Fx00Ywvq0bR/hzzDjpxC1SQam69EF/PqyoYvwDs= Received: from eusmges1new.samsung.com (unknown [203.254.199.242]) by eucas1p1.samsung.com (KnoxPortal) with ESMTP id 20240130090257eucas1p1c595c555b393cc3c01079203e10f2e1c~vFIxnu7vV1567115671eucas1p1E; Tue, 30 Jan 2024 09:02:57 +0000 (GMT) Received: from eucas1p2.samsung.com ( [182.198.249.207]) by eusmges1new.samsung.com (EUCPMTA) with SMTP id 67.24.09539.04BB8B56; Tue, 30 Jan 2024 09:02:56 +0000 (GMT) Received: from eusmtrp1.samsung.com (unknown [182.198.249.138]) by eucas1p1.samsung.com (KnoxPortal) with ESMTPA id 20240130090256eucas1p1f65f4e34dbbd7dec2ac619b7b60ae073~vFIxJt5-O1387013870eucas1p1S; Tue, 30 Jan 2024 09:02:56 +0000 (GMT) Received: from eusmgms2.samsung.com (unknown [182.198.249.180]) by eusmtrp1.samsung.com (KnoxPortal) with ESMTP id 20240130090256eusmtrp11bc05448befd85e707a393fc56944407~vFIxIkU4C3128631286eusmtrp1E; Tue, 30 Jan 2024 09:02:56 +0000 (GMT) X-AuditID: cbfec7f2-515ff70000002543-bd-65b8bb40e463 Received: from eusmtip1.samsung.com ( [203.254.199.221]) by eusmgms2.samsung.com (EUCPMTA) with SMTP id DF.1E.10702.04BB8B56; Tue, 30 Jan 2024 09:02:56 +0000 (GMT) Received: from CAMSVWEXC02.scsc.local (unknown [106.1.227.72]) by eusmtip1.samsung.com (KnoxPortal) with ESMTPA id 20240130090256eusmtip10e72268538ab337e757e9fc1dd96fbbd~vFIw7uTDP2109621096eusmtip1F; Tue, 30 Jan 2024 09:02:56 +0000 (GMT) Received: from CAMSVWEXC02.scsc.local (2002:6a01:e348::6a01:e348) by CAMSVWEXC02.scsc.local (2002:6a01:e348::6a01:e348) with Microsoft SMTP Server (TLS) id 15.0.1497.2; Tue, 30 Jan 2024 09:02:55 +0000 Received: from CAMSVWEXC02.scsc.local ([::1]) by CAMSVWEXC02.scsc.local ([fe80::3c08:6c51:fa0a:6384%13]) with mapi id 15.00.1497.012; Tue, 30 Jan 2024 09:02:55 +0000 From: Andreas Hindborg To: Matthew Wilcox CC: Alice Ryhl , Miguel Ojeda , "Alex Gaynor" , Wedson Almeida Filho , Boqun Feng , Gary Guo , =?iso-8859-1?Q?Bj=F6rn_Roy_Baron?= , Benno Lossin , Kees Cook , Al Viro , Andrew Morton , "Greg Kroah-Hartman" , =?iso-8859-1?Q?Arve_Hj=F8nnev=E5g?= , Todd Kjos , Martijn Coenen , Joel Fernandes , Carlos Llamas , "Suren Baghdasaryan" , Arnd Bergmann , "linux-mm@kvack.org" , "linux-kernel@vger.kernel.org" , "rust-for-linux@vger.kernel.org" , Christian Brauner Subject: Re: [PATCH 3/3] rust: add abstraction for `struct page` Thread-Topic: [PATCH 3/3] rust: add abstraction for `struct page` Thread-Index: AQHaUD8NVXQbcxmBfkinu8UJuZg2mrDxGW2AgAD5TwA= Date: Tue, 30 Jan 2024 09:02:54 +0000 Message-ID: <87mssngpnc.fsf@samsung.com> In-Reply-To: Accept-Language: en-US, en-GB Content-Language: en-US X-MS-Has-Attach: X-MS-TNEF-Correlator: x-ms-exchange-messagesentrepresentingtype: 1 x-ms-exchange-transport-fromentityheader: Hosted x-originating-ip: [106.110.32.64] Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable MIME-Version: 1.0 X-Brightmail-Tracker: H4sIAAAAAAAAA02Sf1CTdRzH+z579jwPQ66HgfIVJyV3ZOkaQv3xPTQk666n6Ad6R2dJxpQn kDagjcHUrgZ4mLQ8AzthoJskILQFzW2YgzYH8UN+GGADOTDjViegKaAZEBjbgx3/vT73fX/e n/fnc1+KJ6wjQqkDGdmsIkMqCycEuK1t9urzcfaL7BZD71ZUUW8k0EJ5I4k6BvNxtFDcRqK7 C78R6J47n4+GfnHwkNGSh6HJlmmA7jv7SdTXPQlQwbf1BKrWRKDuL+Vo4FIFgW4YH/GRzajh o1p9DUD1f7bwUEm/gUAG9xyJri6081FDtQmg+X8qiDjI2Ow2PjM/VwyYck0fzpw7NocxP+pG ScZgVjEXzm9izk4/4DPmumMEY54uJpmO0nmccZw2kszDo00Eoy00Y8yMOYwxe+5gCfT7gm0p rOxADquIjE0WpLmGvsOz9H7qL0xTQANmiSLgR0H6RVhZ1IkXAQElpM8DaLOdAVxxH0D98PcY V8wAON44Ax63LBoKMC8L6RoAr5k++l800HOD5IpuAPMsruX2WgAnHrhwbwtBR0K30c0rAhQV TD8Lb1uivRoe7SHh33aXzzaIjoPu8Ws+fTD9Mmw43k9wHAPbCzSkl3E6Al7Wan0csOST31ns 0/gtxesf7eJ7GdDr4VjtnE/Do0PgsEePcSsEwsryJh7Ha+Dipd+XryGGPYOe5TW3QGvVTzjH G6Bbex1wPhI49M1JguPNsPrsJI/LEAg7yzy+S0Ja6w/HHv6xbPQqrKq7yec4CE60W0iORbCr RIufAJt1K/LpVszQrZihWzHDAPA6EMKqlPJUVhmVweZKlFK5UpWRKtmfKTeDpe/ctdg+fRGc npiSuABGAReAFC88OGD2OSsrDEiRHjzEKjI/VKhkrNIF1lF4eEhARMpTrJBOlWazH7NsFqt4 /IpRfqEaLGb0iOERNtBmsQynqfPuvit4ffvcS2dKPrWO1Lwlas4pFKlG9EkXHCc3mg4fPXGk Nzoua9Bpvdf3uRqE7TyVvW/7lUT7VPKtf/clOrfKtLmv2aLfS0ot2+jSxciDZvMN6QmiSN36 VZOxUel7xuwz4+LGD0ITplp3rPUv3vm1o1CmCBHl3NwvpJ4U72iOWluacvBci1O3ruGHwlyT 2Tra55T+9fae3eQTkpHFW81kfGv68OW9q/WNhz5x+JcmvtnhmVj9WRkI283y71xJGqzSXU+K XXP8hVfeyey9rXaT236uElam7XWoBdmH43tSJsRP17zxa1PgqmdsCfzk1l274sxfaeLF4bgy TRq1iadQSv8D4nuX1D0EAAA= X-Brightmail-Tracker: H4sIAAAAAAAAA02SfUxTVxjGPb23t4Wk866UeMJgm02MClJopfUgrGNmuouZboZsMxqnjd7x IbTYDzf7x1IpTKVs04pka2soE5hgFdZBZXzIKFgQcEzmCpihi3ZzUhjCWIAy2EqvS/jvd877 Ps/7PieHi/GriShutlJLq5WKXCERjvctdY/Gp7U00YmeyWhkq3MQaNF6nYN6hgpwtGj2cNDk 4gMCPfUWsNHwj+0YcjScZCF/5zRAM98PctCdfj9Axkt1BKo2rEP9pjz0U7ONQPcd/7KRy2Fg o5ryrwGq+70TQ+cH7QSyewMcNLDYzUb11VcBWpizEWmQcrW42NRCwAwoq+EOTlWeCbCo7yyj HMru1FHfXo6lKqb/ZlPO2jME5Zw2c6ieLxZwqv2ig0PNnmolqJJPnCzqL+eLlNM3wXqb3CdK Vat0WvrlLJVG+4pwvxhJROJkJJIkJYvEm7cc2CqRChPkqUfo3OzjtDpBfkiU5R6+gueXh310 +uoUMIB5ohiEcSGZBJfsRlYxCOfyySoAT/kbMaYQDb+Z+ZnNcAT8x1scEvDJKQAXy1czgn4A W4sWOMyhBkDTTaaLIBOg1+ENOnG5AnIDHG+QLPdg5EMO9J0cCblGkGnQ++QuvswC8jVY/9kg wfBW2G00cJYZJ9fBjpKSEPOCPgW3zAQzbCK4avNIqBAWzDA42hcyBWQMfFgTCN1j5Bp4z1fO YiKQsLJ14Fm0SPjk0dKzaJvg7SEfYDgRNlbdwBleC70lI4DxEcHhC6UEw3GwusKPMQs9D299 6cPPghcsK8ZZVkgsKySWFRI7wGuBgNZp8jLzNBKRRpGn0SkzRYdVeU4Q/LAuz3xDE6gZmxK5 AYsL3AByMaGAN7+xkebzjihO6Gm16qBal0tr3EAafKRzWFTkYVXwxyu1B8WyRKk4SZacKE2W bRau4aXnn1bwyUyFlj5K0/m0+n8dixsWZWDtjMPbju+pOsYX3hck1NsCCdaYQ2LJhtkida+c p4qMrh4rVV37atcVd6k8xW/dlC3+mBRgMuvumbdqcevINB1emP5e/lLiox+u5Txo6xkwDi3s 6f3DeWCj9zdj2fvn9NFo0hS/vnC8tfO5dwWex+MdsrgU+edW+e3Y7a/qt/wpl/hduvC5HTk5 nZe2Vcx2bC/6Zaj0gvXoRakJZhxL83yg6zIXfJgaY9u3VDb31H137f72d+7VXN4br3xzPYnV v37zem2Lre+NvRMdN3ZKfk1KydCvOuEOVOyIi6xUtOnHIpolfatNU2O9hWTX2ab0bTPN7K7J VS0Zn76Utvuxbhf3vLRMiGuyFOJYTK1R/AecrINTOQQAAA== X-CMS-MailID: 20240130090256eucas1p1f65f4e34dbbd7dec2ac619b7b60ae073 X-Msg-Generator: CA X-RootMTR: 20240129180005eucas1p1c1962ece31e6b9619f9e22dc95f54087 X-EPHeader: CA CMS-TYPE: 201P X-CMS-RootMailID: 20240129180005eucas1p1c1962ece31e6b9619f9e22dc95f54087 References: <20240124-alice-mm-v1-0-d1abcec83c44@google.com> <20240124-alice-mm-v1-3-d1abcec83c44@google.com> X-Rspam-User: X-Rspamd-Server: rspam12 X-Rspamd-Queue-Id: 12D8C160017 X-Stat-Signature: rmxjyf9ktu1sag8b4k7qinowe35ay7nc X-HE-Tag: 1706605380-169667 X-HE-Meta: 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 EPmRtSiO qGoaWhhE3Xm0mfDEfipsvvAe6hhjs3NGF9v6HxeA6DML3AcaX3xZMGAhTL1aBO3udljPLWd3S7YE0XX5Nba470A8K2h4f1v2LyTM2Xu+bO8EaydtDyJTGq5V/LGUzhq+cNehtc13W7o8ouJPMqa2+FjlR8uvSsE5kb2bcNDfJeug15sripzlJvtLTIpyy7mRmIYFyCU+fJfNaW7m7UYaGdObpsAQ8Q2DLrasvfnU7KoXXWyU= 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: Matthew Wilcox writes: > On Wed, Jan 24, 2024 at 11:20:23AM +0000, Alice Ryhl wrote: >> +impl Page { >> + /// Allocates a new set of contiguous pages. >> + pub fn new() -> Result { >> + // SAFETY: These are the correct arguments to allocate a single= page. >> + let page =3D unsafe { >> + bindings::alloc_pages( >> + bindings::GFP_KERNEL | bindings::__GFP_ZERO | bindings:= :__GFP_HIGHMEM, >> + 0, >> + ) >> + }; > > This feels too Binder-specific to be 'Page'. Pages are not necessarily > allocated with GFP_HIGHMEM, nor are they necessarily zeroed. Maybe you > want a BinderPage type? Rust null block uses the same definition of these flags [1], so there is at least that synergy. I feel like we had the discussion of the flags before, although I can't find the thread now. I think the conclusion was that we fix them until we have code that need to actually change them (as to not add dead code). BR Andreas [1] https://github.com/metaspace/linux/blob/702026e6645193fc89b7d55e00dac75= fd492bfb8/rust/kernel/pages.rs#L28=