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 X-Spam-Level: X-Spam-Status: No, score=-9.9 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH, MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED, USER_AGENT_GIT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 7FDA1C433E4 for ; Tue, 19 May 2020 00:21:35 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 53FE920873 for ; Tue, 19 May 2020 00:21:35 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=nvidia.com header.i=@nvidia.com header.b="Gqj1Eegd" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727782AbgESAVe (ORCPT ); Mon, 18 May 2020 20:21:34 -0400 Received: from hqnvemgate25.nvidia.com ([216.228.121.64]:5636 "EHLO hqnvemgate25.nvidia.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726958AbgESAVb (ORCPT ); Mon, 18 May 2020 20:21:31 -0400 Received: from hqpgpgate101.nvidia.com (Not Verified[216.228.121.13]) by hqnvemgate25.nvidia.com (using TLS: TLSv1.2, DES-CBC3-SHA) id ; Mon, 18 May 2020 17:20:13 -0700 Received: from hqmail.nvidia.com ([172.20.161.6]) by hqpgpgate101.nvidia.com (PGP Universal service); Mon, 18 May 2020 17:21:31 -0700 X-PGP-Universal: processed; by hqpgpgate101.nvidia.com on Mon, 18 May 2020 17:21:31 -0700 Received: from HQMAIL101.nvidia.com (172.20.187.10) by HQMAIL105.nvidia.com (172.20.187.12) with Microsoft SMTP Server (TLS) id 15.0.1473.3; Tue, 19 May 2020 00:21:29 +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, 19 May 2020 00:21:28 +0000 Received: from sandstorm.nvidia.com (Not Verified[10.2.55.90]) by rnnvemgw01.nvidia.com with Trustwave SEG (v7,5,8,10121) id ; Mon, 18 May 2020 17:21:28 -0700 From: John Hubbard To: Andrew Morton CC: Souptick Joarder , Matthew Wilcox , Jani Nikula , "Joonas Lahtinen" , Rodrigo Vivi , David Airlie , Daniel Vetter , Chris Wilson , Tvrtko Ursulin , Matthew Auld , , , LKML , , John Hubbard Subject: [PATCH 4/4] drm/i915: convert get_user_pages() --> pin_user_pages() Date: Mon, 18 May 2020 17:21:24 -0700 Message-ID: <20200519002124.2025955-5-jhubbard@nvidia.com> X-Mailer: git-send-email 2.26.2 In-Reply-To: <20200519002124.2025955-1-jhubbard@nvidia.com> References: <20200519002124.2025955-1-jhubbard@nvidia.com> MIME-Version: 1.0 X-NVConfidentiality: public Content-Transfer-Encoding: quoted-printable Content-Type: text/plain DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=nvidia.com; s=n1; t=1589847613; bh=TYbuD5RgYulyxagO4AixT7wa6RlCT1nu+LHkKhXb+U4=; h=X-PGP-Universal:From:To:CC:Subject:Date:Message-ID:X-Mailer: In-Reply-To:References:MIME-Version:X-NVConfidentiality: Content-Transfer-Encoding:Content-Type; b=Gqj1Eegdl4gP6WKGR/AfRzVgeB1rieQnkY/5QKS1v17W3pTdlbPatr7P0KRNamUJ1 trfX9G86fGzJ8KIRUpetIf/3+vFjAwj6rv7NIk0Pw3rLdIXgPRDG6mYpN85oPGlWSz 1+8oi0L/H8w2qox/LNkCIsZecujkQzxG33hzU5exEodgLgOs9xo84w2XpvtZBuO0yr XL+ZM83TH7J7hI2YgMZR0MLmb33DqQVMwPH7nBcAUx7O0cfgbGt1zzNpyrqq68QpY0 +bhCLH0VRb8ZJDkAL5YGTQ78ccRofCa9tZ19PmfqSa52Rikx4UIfo0NSGLpyCqMQp/ 6gFhc7WikkWtg== Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org This code was using get_user_pages*(), in a "Case 2" scenario (DMA/RDMA), using the categorization from [1]. That means that it's time to convert the get_user_pages*() + put_page() calls to pin_user_pages*() + unpin_user_pages() calls. There is some helpful background in [2]: basically, this is a small part of fixing a long-standing disconnect between pinning pages, and file systems' use of those pages. [1] Documentation/core-api/pin_user_pages.rst [2] "Explicit pinning of user-space pages": https://lwn.net/Articles/807108/ Signed-off-by: John Hubbard --- drivers/gpu/drm/i915/gem/i915_gem_userptr.c | 22 ++++++++++++--------- 1 file changed, 13 insertions(+), 9 deletions(-) diff --git a/drivers/gpu/drm/i915/gem/i915_gem_userptr.c b/drivers/gpu/drm/= i915/gem/i915_gem_userptr.c index 7ffd7afeb7a5..b55ac7563189 100644 --- a/drivers/gpu/drm/i915/gem/i915_gem_userptr.c +++ b/drivers/gpu/drm/i915/gem/i915_gem_userptr.c @@ -471,7 +471,7 @@ __i915_gem_userptr_get_pages_worker(struct work_struct = *_work) down_read(&mm->mmap_sem); locked =3D 1; } - ret =3D get_user_pages_remote + ret =3D pin_user_pages_remote (work->task, mm, obj->userptr.ptr + pinned * PAGE_SIZE, npages - pinned, @@ -507,7 +507,7 @@ __i915_gem_userptr_get_pages_worker(struct work_struct = *_work) } mutex_unlock(&obj->mm.lock); =20 - release_pages(pvec, pinned); + unpin_user_pages(pvec, pinned); kvfree(pvec); =20 i915_gem_object_put(obj); @@ -564,6 +564,7 @@ static int i915_gem_userptr_get_pages(struct drm_i915_g= em_object *obj) struct sg_table *pages; bool active; int pinned; + unsigned int gup_flags =3D 0; =20 /* If userspace should engineer that these pages are replaced in * the vma between us binding this page into the GTT and completion @@ -598,11 +599,14 @@ static int i915_gem_userptr_get_pages(struct drm_i915= _gem_object *obj) GFP_KERNEL | __GFP_NORETRY | __GFP_NOWARN); - if (pvec) /* defer to worker if malloc fails */ - pinned =3D __get_user_pages_fast(obj->userptr.ptr, - num_pages, - !i915_gem_object_is_readonly(obj), - pvec); + /* defer to worker if malloc fails */ + if (pvec) { + if (!i915_gem_object_is_readonly(obj)) + gup_flags |=3D FOLL_WRITE; + pinned =3D pin_user_pages_fast_only(obj->userptr.ptr, + num_pages, gup_flags, + pvec); + } } =20 active =3D false; @@ -620,7 +624,7 @@ static int i915_gem_userptr_get_pages(struct drm_i915_g= em_object *obj) __i915_gem_userptr_set_active(obj, true); =20 if (IS_ERR(pages)) - release_pages(pvec, pinned); + unpin_user_pages(pvec, pinned); kvfree(pvec); =20 return PTR_ERR_OR_ZERO(pages); @@ -675,7 +679,7 @@ i915_gem_userptr_put_pages(struct drm_i915_gem_object *= obj, } =20 mark_page_accessed(page); - put_page(page); + unpin_user_page(page); } obj->mm.dirty =3D false; =20 --=20 2.26.2