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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 Content-Type: text/plain; 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> > 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=