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 264D0C433F5 for ; Sun, 6 Mar 2022 02:58:12 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id 645396B0071; Sat, 5 Mar 2022 21:58:12 -0500 (EST) Received: by kanga.kvack.org (Postfix, from userid 40) id 5F4EF6B0072; Sat, 5 Mar 2022 21:58:12 -0500 (EST) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 4E3456B0073; Sat, 5 Mar 2022 21:58:12 -0500 (EST) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (relay.a.hostedemail.com [64.99.140.24]) by kanga.kvack.org (Postfix) with ESMTP id 4035F6B0071 for ; Sat, 5 Mar 2022 21:58:12 -0500 (EST) Received: from smtpin06.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay10.hostedemail.com (Postfix) with ESMTP id 075C411DE for ; Sun, 6 Mar 2022 02:58:12 +0000 (UTC) X-FDA: 79212452424.06.4B6062B Received: from casper.infradead.org (casper.infradead.org [90.155.50.34]) by imf12.hostedemail.com (Postfix) with ESMTP id 4241840009 for ; Sun, 6 Mar 2022 02:58:11 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=casper.20170209; h=In-Reply-To:Content-Type:MIME-Version: References:Message-ID:Subject:Cc:To:From:Date:Sender:Reply-To: Content-Transfer-Encoding:Content-ID:Content-Description; bh=TvYRN1YmUBdHSWPYQwg2K3EE2AkUEhTFgrDPAkH+IiY=; b=mKq4YwMS6eUAxFggJkyGM2x7hn C6PrW9vm1cR73JF+afzt0DHevDIgFxF8zX+NMeez5fBEFTChhRgNzjz71qFtB4NPllNdVa/PJHKHA sTyZt6GjlkEZ30FyhadWd78j/rNd6vWnWjuX6Rh84K3pLCg2Je1zHkIFf1VDTv2/Eeh3wqt/oEQyX UznNY0HjgIGb/bYsVBZhZu9zFIfUu7F48Q8tEEJHDryC+pNpdNViBX8BnpsvkA+FwmuCTl9+vxCCH BH8zaYFk9GHzvTXZA+AbTajg5+My6nID+Go5DHMCGTB7EFc3mXzx2e5FHcvkLmgKaFosZfV6fweUl 4HJ1/eYg==; Received: from willy by casper.infradead.org with local (Exim 4.94.2 #2 (Red Hat Linux)) id 1nQh5n-00E3CB-Eu; Sun, 06 Mar 2022 02:57:55 +0000 Date: Sun, 6 Mar 2022 02:57:55 +0000 From: Matthew Wilcox To: Jarkko Sakkinen Cc: Andrew Morton , Dave Hansen , Nathaniel McCallum , Reinette Chatre , linux-sgx@vger.kernel.org, linux-mips@vger.kernel.org, linux-kernel@vger.kernel.org, intel-gfx@lists.freedesktop.org, dri-devel@lists.freedesktop.org, codalist@coda.cs.cmu.edu, linux-unionfs@vger.kernel.org, linux-fsdevel@vger.kernel.org, linux-mm@kvack.org Subject: Re: [PATCH RFC] mm: Add f_ops->populate() Message-ID: References: <20220306021534.83553-1-jarkko@kernel.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20220306021534.83553-1-jarkko@kernel.org> X-Rspamd-Queue-Id: 4241840009 X-Stat-Signature: s911do1yypcb3jje8inbzstwc5eckrns X-Rspam-User: Authentication-Results: imf12.hostedemail.com; dkim=pass header.d=infradead.org header.s=casper.20170209 header.b=mKq4YwMS; spf=none (imf12.hostedemail.com: domain of willy@infradead.org has no SPF policy when checking 90.155.50.34) smtp.mailfrom=willy@infradead.org; dmarc=none X-Rspamd-Server: rspam07 X-HE-Tag: 1646535491-508391 X-Bogosity: Ham, tests=bogofilter, spamicity=0.000381, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: On Sun, Mar 06, 2022 at 04:15:33AM +0200, Jarkko Sakkinen wrote: > Sometimes you might want to use MAP_POPULATE to ask a device driver to > initialize the device memory in some specific manner. SGX driver can use > this to request more memory by issuing ENCLS[EAUG] x86 opcode for each > page in the address range. > > Add f_ops->populate() with the same parameters as f_ops->mmap() and make > it conditionally called inside call_mmap(). Update call sites > accodingly. Your device driver has a ->mmap operation. Why does it need another one? More explanation required here.