From patchwork Tue Nov 12 00:06:49 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: John Hubbard X-Patchwork-Id: 11238277 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 0009A14E5 for ; Tue, 12 Nov 2019 00:10:01 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id D26002184C for ; Tue, 12 Nov 2019 00:10:01 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=nvidia.com header.i=@nvidia.com header.b="PqOu2gGr" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727730AbfKLAJv (ORCPT ); Mon, 11 Nov 2019 19:09:51 -0500 Received: from hqemgate15.nvidia.com ([216.228.121.64]:16681 "EHLO hqemgate15.nvidia.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727417AbfKLAHT (ORCPT ); Mon, 11 Nov 2019 19:07:19 -0500 Received: from hqpgpgate102.nvidia.com (Not Verified[216.228.121.13]) by hqemgate15.nvidia.com (using TLS: TLSv1.2, DES-CBC3-SHA) id ; Mon, 11 Nov 2019 16:06:16 -0800 Received: from hqmail.nvidia.com ([172.20.161.6]) by hqpgpgate102.nvidia.com (PGP Universal service); Mon, 11 Nov 2019 16:07:18 -0800 X-PGP-Universal: processed; by hqpgpgate102.nvidia.com on Mon, 11 Nov 2019 16:07:18 -0800 Received: from HQMAIL101.nvidia.com (172.20.187.10) by HQMAIL101.nvidia.com (172.20.187.10) with Microsoft SMTP Server (TLS) id 15.0.1473.3; Tue, 12 Nov 2019 00:07:18 +0000 Received: from rnnvemgw01.nvidia.com (10.128.109.123) by HQMAIL101.nvidia.com (172.20.187.10) with Microsoft SMTP Server (TLS) id 15.0.1473.3 via Frontend Transport; Tue, 12 Nov 2019 00:07:16 +0000 Received: from blueforge.nvidia.com (Not Verified[10.110.48.28]) by rnnvemgw01.nvidia.com with Trustwave SEG (v7,5,8,10121) id ; Mon, 11 Nov 2019 16:07:16 -0800 From: John Hubbard To: Andrew Morton CC: Al Viro , Alex Williamson , Benjamin Herrenschmidt , =?utf-8?b?QmrDtnJuIFQ=?= =?utf-8?b?w7ZwZWw=?= , Christoph Hellwig , Dan Williams , Daniel Vetter , Dave Chinner , David Airlie , "David S . Miller" , Ira Weiny , Jan Kara , Jason Gunthorpe , Jens Axboe , Jonathan Corbet , =?utf-8?b?SsOpcsO0bWUgR2xpc3Nl?= , Magnus Karlsson , Mauro Carvalho Chehab , Michael Ellerman , Michal Hocko , Mike Kravetz , Paul Mackerras , Shuah Khan , Vlastimil Babka , , , , , , , , , , , , , LKML , John Hubbard Subject: [PATCH v3 12/23] mm/process_vm_access: set FOLL_PIN via pin_user_pages_remote() Date: Mon, 11 Nov 2019 16:06:49 -0800 Message-ID: <20191112000700.3455038-13-jhubbard@nvidia.com> X-Mailer: git-send-email 2.24.0 In-Reply-To: <20191112000700.3455038-1-jhubbard@nvidia.com> References: <20191112000700.3455038-1-jhubbard@nvidia.com> MIME-Version: 1.0 X-NVConfidentiality: public DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=nvidia.com; s=n1; t=1573517176; bh=3Py2O4K3WxT2/yPBKlFkEQrJEl3zr7dYM5uV5CiR5XQ=; h=X-PGP-Universal:From:To:CC:Subject:Date:Message-ID:X-Mailer: In-Reply-To:References:MIME-Version:X-NVConfidentiality: Content-Type:Content-Transfer-Encoding; b=PqOu2gGrt4yPc1T9tX6zhkH7invPzsZgO/C6ZqE5zQz2DIFQw9DLsdHGiEQsACOmr REvLimBqdAK3G9Lka7QSCUjGMiiCJ9Umq1kHatYlMcRQGoZ9t2mcKgFgxyTIgxFkFe KyvKAvPkOkGw1ZAWdb7VYga194WAjTUMv5r/TECnVFi0ryPvMt0BO6GMSf4RaS4B2+ HfkAZ3USwjZCq4qwGgr5t17jk5mnULpsYxHQBC/D4gBwrquycyRjvppfg2l8HjCZvp rezKt17AgS7ee8655DgxOQkn6ddMRB2xTS87e8KOEiBpRL0NLea8Fi7NHa9l5Gzz38 AMpQAKqOX5wUA== Sender: kvm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org Convert process_vm_access to use the new pin_user_pages_remote() call, which sets FOLL_PIN. Setting FOLL_PIN is now required for code that requires tracking of pinned pages. Also, release the pages via put_user_page*(). Also, rename "pages" to "pinned_pages", as this makes for easier reading of process_vm_rw_single_vec(). Reviewed-by: Jérôme Glisse Reviewed-by: Ira Weiny Signed-off-by: John Hubbard --- mm/process_vm_access.c | 28 +++++++++++++++------------- 1 file changed, 15 insertions(+), 13 deletions(-) diff --git a/mm/process_vm_access.c b/mm/process_vm_access.c index 357aa7bef6c0..fd20ab675b85 100644 --- a/mm/process_vm_access.c +++ b/mm/process_vm_access.c @@ -42,12 +42,11 @@ static int process_vm_rw_pages(struct page **pages, if (copy > len) copy = len; - if (vm_write) { + if (vm_write) copied = copy_page_from_iter(page, offset, copy, iter); - set_page_dirty_lock(page); - } else { + else copied = copy_page_to_iter(page, offset, copy, iter); - } + len -= copied; if (copied < copy && iov_iter_count(iter)) return -EFAULT; @@ -96,7 +95,7 @@ static int process_vm_rw_single_vec(unsigned long addr, flags |= FOLL_WRITE; while (!rc && nr_pages && iov_iter_count(iter)) { - int pages = min(nr_pages, max_pages_per_loop); + int pinned_pages = min(nr_pages, max_pages_per_loop); int locked = 1; size_t bytes; @@ -106,14 +105,15 @@ static int process_vm_rw_single_vec(unsigned long addr, * current/current->mm */ down_read(&mm->mmap_sem); - pages = get_user_pages_remote(task, mm, pa, pages, flags, - process_pages, NULL, &locked); + pinned_pages = pin_user_pages_remote(task, mm, pa, pinned_pages, + flags, process_pages, + NULL, &locked); if (locked) up_read(&mm->mmap_sem); - if (pages <= 0) + if (pinned_pages <= 0) return -EFAULT; - bytes = pages * PAGE_SIZE - start_offset; + bytes = pinned_pages * PAGE_SIZE - start_offset; if (bytes > len) bytes = len; @@ -122,10 +122,12 @@ static int process_vm_rw_single_vec(unsigned long addr, vm_write); len -= bytes; start_offset = 0; - nr_pages -= pages; - pa += pages * PAGE_SIZE; - while (pages) - put_page(process_pages[--pages]); + nr_pages -= pinned_pages; + pa += pinned_pages * PAGE_SIZE; + + /* If vm_write is set, the pages need to be made dirty: */ + put_user_pages_dirty_lock(process_pages, pinned_pages, + vm_write); } return rc;