From patchwork Wed Oct 7 16:44:18 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: Daniel Vetter X-Patchwork-Id: 11821153 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 D35C614D5 for ; Wed, 7 Oct 2020 16:45:16 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id A98C82087D for ; Wed, 7 Oct 2020 16:45:16 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=ffwll.ch header.i=@ffwll.ch header.b="ZCR6epNG" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728707AbgJGQpK (ORCPT ); Wed, 7 Oct 2020 12:45:10 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:52672 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728151AbgJGQom (ORCPT ); Wed, 7 Oct 2020 12:44:42 -0400 Received: from mail-wm1-x343.google.com (mail-wm1-x343.google.com [IPv6:2a00:1450:4864:20::343]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 708ECC0613D6 for ; Wed, 7 Oct 2020 09:44:41 -0700 (PDT) Received: by mail-wm1-x343.google.com with SMTP id q5so3145173wmq.0 for ; Wed, 07 Oct 2020 09:44:41 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=ffwll.ch; s=google; h=from:to:cc:subject:date:message-id:in-reply-to:references :mime-version:content-transfer-encoding; bh=tumapzZxvtArZNF04352kaumd5zWdbY4K/o9+R8ZPiU=; b=ZCR6epNGq4y9pMu5KQprul9p0e5pbHRNVWh8gfzFX5t78d6KExLodPu0cge87TbHQ7 IFCUDLlXaw9OhMaO8M6ZionCebVY74YdmCbAxhY4ZzIXmKSQNldnw8FEWkuV3IgYHDwi 4BgN7dseD1BVSXWfbIbpwPFDfQHHYpunWAI44= X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:date:message-id:in-reply-to :references:mime-version:content-transfer-encoding; bh=tumapzZxvtArZNF04352kaumd5zWdbY4K/o9+R8ZPiU=; b=JxxuElfmlo8jxSabZ39MdV2FqL2Ha8xSyIcVDmss8Z8M9PgXtuxtBSFLstpDtA4v0x 4Ac6b0NhUCBzCcBnhKNSxsXA+YeiFPZQ1OCAwAaXPDJrpW3aIrV2mBAUtnvUd8QFfiY8 kp+AQ2+jnujoa+Mqaf0YG/IbMlq4Cg7aC97xbdBYkLZWKZUK31TkiPLKQzj9c9YL0MkO SvVWP1AyJxt2bVMwbk6+npSu8Gj9VYAT738mnIQoQT+II/SnLMcVzW0tPyG7Po12xpz7 Ia4/CkN5QW4szNLwysbPcwAKXlRdHfJEUTpMoPRJU8tdDx57hRb7pz/OLGzgh12PSdJv eSdQ== X-Gm-Message-State: AOAM531ABqhTOI6lzbAAN7rx5ZfLG28oIxMbgH84vnFWQ/P3v1kzWl+S PVoKui55ZoOYK2Q3UGTmOp0rPg== X-Google-Smtp-Source: ABdhPJzV4N2gLoUB2iCJL2idqYl1jr0gD0FniH6eb95jw+Xbq6j8k/dKxJZkk3IRomSCwD32oRnJ8Q== X-Received: by 2002:a1c:a7cc:: with SMTP id q195mr4218149wme.8.1602089080062; Wed, 07 Oct 2020 09:44:40 -0700 (PDT) Received: from phenom.ffwll.local ([2a02:168:57f4:0:efd0:b9e5:5ae6:c2fa]) by smtp.gmail.com with ESMTPSA id z191sm3332280wme.40.2020.10.07.09.44.38 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Wed, 07 Oct 2020 09:44:39 -0700 (PDT) From: Daniel Vetter To: DRI Development , LKML Cc: kvm@vger.kernel.org, linux-mm@kvack.org, linux-arm-kernel@lists.infradead.org, linux-samsung-soc@vger.kernel.org, linux-media@vger.kernel.org, linux-s390@vger.kernel.org, Daniel Vetter , Daniel Vetter , Jason Gunthorpe , Pawel Osciak , Marek Szyprowski , Kyungmin Park , Tomasz Figa , Mauro Carvalho Chehab , Andrew Morton , John Hubbard , =?utf-8?b?SsOpcsO0bWUgR2xpc3Nl?= , Jan Kara , Dan Williams Subject: [PATCH 05/13] mm/frame-vector: Use FOLL_LONGTERM Date: Wed, 7 Oct 2020 18:44:18 +0200 Message-Id: <20201007164426.1812530-6-daniel.vetter@ffwll.ch> X-Mailer: git-send-email 2.28.0 In-Reply-To: <20201007164426.1812530-1-daniel.vetter@ffwll.ch> References: <20201007164426.1812530-1-daniel.vetter@ffwll.ch> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org This is used by media/videbuf2 for persistent dma mappings, not just for a single dma operation and then freed again, so needs FOLL_LONGTERM. Unfortunately current pup_locked doesn't support FOLL_LONGTERM due to locking issues. Rework the code to pull the pup path out from the mmap_sem critical section as suggested by Jason. Signed-off-by: Daniel Vetter Cc: Jason Gunthorpe Cc: Pawel Osciak Cc: Marek Szyprowski Cc: Kyungmin Park Cc: Tomasz Figa Cc: Mauro Carvalho Chehab Cc: Andrew Morton Cc: John Hubbard Cc: Jérôme Glisse Cc: Jan Kara Cc: Dan Williams Cc: linux-mm@kvack.org Cc: linux-arm-kernel@lists.infradead.org Cc: linux-samsung-soc@vger.kernel.org Cc: linux-media@vger.kernel.org --- mm/frame_vector.c | 36 +++++++++++------------------------- 1 file changed, 11 insertions(+), 25 deletions(-) diff --git a/mm/frame_vector.c b/mm/frame_vector.c index 10f82d5643b6..39db520a51dc 100644 --- a/mm/frame_vector.c +++ b/mm/frame_vector.c @@ -38,7 +38,6 @@ int get_vaddr_frames(unsigned long start, unsigned int nr_frames, struct vm_area_struct *vma; int ret = 0; int err; - int locked; if (nr_frames == 0) return 0; @@ -48,35 +47,22 @@ int get_vaddr_frames(unsigned long start, unsigned int nr_frames, start = untagged_addr(start); + ret = pin_user_pages_fast(start, nr_frames, + FOLL_FORCE | FOLL_WRITE | FOLL_LONGTERM, + (struct page **)(vec->ptrs)); + if (ret > 0) { + vec->got_ref = true; + vec->is_pfns = false; + goto out_unlocked; + } + mmap_read_lock(mm); - locked = 1; vma = find_vma_intersection(mm, start, start + 1); if (!vma) { ret = -EFAULT; goto out; } - /* - * While get_vaddr_frames() could be used for transient (kernel - * controlled lifetime) pinning of memory pages all current - * users establish long term (userspace controlled lifetime) - * page pinning. Treat get_vaddr_frames() like - * get_user_pages_longterm() and disallow it for filesystem-dax - * mappings. - */ - if (vma_is_fsdax(vma)) { - ret = -EOPNOTSUPP; - goto out; - } - - if (!(vma->vm_flags & (VM_IO | VM_PFNMAP))) { - vec->got_ref = true; - vec->is_pfns = false; - ret = pin_user_pages_locked(start, nr_frames, - gup_flags, (struct page **)(vec->ptrs), &locked); - goto out; - } - vec->got_ref = false; vec->is_pfns = true; do { @@ -101,8 +87,8 @@ int get_vaddr_frames(unsigned long start, unsigned int nr_frames, vma = find_vma_intersection(mm, start, start + 1); } while (vma && vma->vm_flags & (VM_IO | VM_PFNMAP)); out: - if (locked) - mmap_read_unlock(mm); + mmap_read_unlock(mm); +out_unlocked: if (!ret) ret = -EFAULT; if (ret > 0)