From patchwork Mon Nov 25 04:20:00 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: John Hubbard X-Patchwork-Id: 11259519 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 AA22915AC for ; Mon, 25 Nov 2019 04:20:19 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 8A5EF20823 for ; Mon, 25 Nov 2019 04:20:19 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=nvidia.com header.i=@nvidia.com header.b="okQ/hciu" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727191AbfKYEUS (ORCPT ); Sun, 24 Nov 2019 23:20:18 -0500 Received: from hqemgate15.nvidia.com ([216.228.121.64]:9137 "EHLO hqemgate15.nvidia.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727004AbfKYEUQ (ORCPT ); Sun, 24 Nov 2019 23:20:16 -0500 Received: from hqpgpgate101.nvidia.com (Not Verified[216.228.121.13]) by hqemgate15.nvidia.com (using TLS: TLSv1.2, DES-CBC3-SHA) id ; Sun, 24 Nov 2019 20:20:09 -0800 Received: from hqmail.nvidia.com ([172.20.161.6]) by hqpgpgate101.nvidia.com (PGP Universal service); Sun, 24 Nov 2019 20:20:14 -0800 X-PGP-Universal: processed; by hqpgpgate101.nvidia.com on Sun, 24 Nov 2019 20:20:14 -0800 Received: from HQMAIL109.nvidia.com (172.20.187.15) by HQMAIL107.nvidia.com (172.20.187.13) with Microsoft SMTP Server (TLS) id 15.0.1473.3; Mon, 25 Nov 2019 04:20:13 +0000 Received: from hqnvemgw03.nvidia.com (10.124.88.68) by HQMAIL109.nvidia.com (172.20.187.15) with Microsoft SMTP Server (TLS) id 15.0.1473.3 via Frontend Transport; Mon, 25 Nov 2019 04:20:13 +0000 Received: from blueforge.nvidia.com (Not Verified[10.110.48.28]) by hqnvemgw03.nvidia.com with Trustwave SEG (v7,5,8,10121) id ; Sun, 24 Nov 2019 20:20:13 -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 08/19] goldish_pipe: convert to pin_user_pages() and put_user_page() Date: Sun, 24 Nov 2019 20:20:00 -0800 Message-ID: <20191125042011.3002372-9-jhubbard@nvidia.com> X-Mailer: git-send-email 2.24.0 In-Reply-To: <20191125042011.3002372-1-jhubbard@nvidia.com> References: <20191125042011.3002372-1-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=1574655609; bh=TksWTeRqb2e65v/kOUv6DZsbenXYEnzjjPNzfVXQEtw=; 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=okQ/hciuf1TsfHPj4jP21tGs0LHIODWdZSch4a/YbvMYYU8i9AJmeCInhSI8pdRWN mEJBemKWoN3JUsupBbdV3M5BUL94rg3JZn1e8LJyoRa2uRlbUY8ijAQkfUWxEak4VB Gwke9Kex7V+s1SWBJAXTU2gzY6OTg+6MNhV9YzBec5MiI3uA5GsuT3OmeBoxYYKv/m c5Iv/pZtN7VbeyibYMmBp6XaDBFKnpuCk+7nTtTfOwb4rMTQeVrRdYZDyqc9qkdbyt XkO3YuAqEWQLeYcl9yr64macIubH2Gb61DryRHJUD7y2URTrZHatcDS+iV9VibgmPU 9ZiCrOv1Ze+Tw== Sender: kvm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org 1. Call the new global pin_user_pages_fast(), from pin_goldfish_pages(). 2. As required by pin_user_pages(), release these pages via put_user_page(). In this case, do so via put_user_pages_dirty_lock(). That has the side effect of calling set_page_dirty_lock(), instead of set_page_dirty(). This is probably more accurate. As Christoph Hellwig put it, "set_page_dirty() is only safe if we are dealing with a file backed page where we have reference on the inode it hangs off." [1] Another side effect is that the release code is simplified because the page[] loop is now in gup.c instead of here, so just delete the local release_user_pages() entirely, and call put_user_pages_dirty_lock() directly, instead. [1] https://lore.kernel.org/r/20190723153640.GB720@lst.de Reviewed-by: Jan Kara Reviewed-by: Ira Weiny Signed-off-by: John Hubbard --- drivers/platform/goldfish/goldfish_pipe.c | 17 +++-------------- 1 file changed, 3 insertions(+), 14 deletions(-) diff --git a/drivers/platform/goldfish/goldfish_pipe.c b/drivers/platform/goldfish/goldfish_pipe.c index ef50c264db71..2a5901efecde 100644 --- a/drivers/platform/goldfish/goldfish_pipe.c +++ b/drivers/platform/goldfish/goldfish_pipe.c @@ -274,7 +274,7 @@ static int goldfish_pin_pages(unsigned long first_page, *iter_last_page_size = last_page_size; } - ret = get_user_pages_fast(first_page, requested_pages, + ret = pin_user_pages_fast(first_page, requested_pages, !is_write ? FOLL_WRITE : 0, pages); if (ret <= 0) @@ -285,18 +285,6 @@ static int goldfish_pin_pages(unsigned long first_page, return ret; } -static void release_user_pages(struct page **pages, int pages_count, - int is_write, s32 consumed_size) -{ - int i; - - for (i = 0; i < pages_count; i++) { - if (!is_write && consumed_size > 0) - set_page_dirty(pages[i]); - put_page(pages[i]); - } -} - /* Populate the call parameters, merging adjacent pages together */ static void populate_rw_params(struct page **pages, int pages_count, @@ -372,7 +360,8 @@ static int transfer_max_buffers(struct goldfish_pipe *pipe, *consumed_size = pipe->command_buffer->rw_params.consumed_size; - release_user_pages(pipe->pages, pages_count, is_write, *consumed_size); + put_user_pages_dirty_lock(pipe->pages, pages_count, + !is_write && *consumed_size > 0); mutex_unlock(&pipe->lock); return 0;