From patchwork Mon Nov 25 04:20:09 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: John Hubbard X-Patchwork-Id: 11259747 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 8B7E115AC for ; Mon, 25 Nov 2019 04:22:36 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 6B83920840 for ; Mon, 25 Nov 2019 04:22:36 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=nvidia.com header.i=@nvidia.com header.b="gNTBO2iB" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727648AbfKYEV7 (ORCPT ); Sun, 24 Nov 2019 23:21:59 -0500 Received: from hqemgate15.nvidia.com ([216.228.121.64]:9229 "EHLO hqemgate15.nvidia.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727266AbfKYEUV (ORCPT ); Sun, 24 Nov 2019 23:20:21 -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 20:20:10 -0800 Received: from hqmail.nvidia.com ([172.20.161.6]) by hqpgpgate101.nvidia.com (PGP Universal service); Sun, 24 Nov 2019 20:20:15 -0800 X-PGP-Universal: processed; by hqpgpgate101.nvidia.com on Sun, 24 Nov 2019 20:20:15 -0800 Received: from HQMAIL111.nvidia.com (172.20.187.18) by HQMAIL111.nvidia.com (172.20.187.18) with Microsoft SMTP Server (TLS) id 15.0.1473.3; Mon, 25 Nov 2019 04:20:14 +0000 Received: from hqnvemgw03.nvidia.com (10.124.88.68) by HQMAIL111.nvidia.com (172.20.187.18) with Microsoft SMTP Server (TLS) id 15.0.1473.3 via Frontend Transport; Mon, 25 Nov 2019 04:20:14 +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 20:20:14 -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 17/19] powerpc: book3s64: convert to pin_user_pages() and put_user_page() Date: Sun, 24 Nov 2019 20:20:09 -0800 Message-ID: <20191125042011.3002372-18-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=1574655610; bh=IJJb9r+CEPs17zzIv7S9Yy1snV6WhIVmX2ftMMVKd1c=; 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=gNTBO2iB4EBi3rbOQgTZAr8HuUuxejicGMXpfQWBvr+E1GHmXHRYN1eOEszl2gv+m gR3lV2gCwOi9NaE81WhakqlTipHB7/mvKCI3w6DvY34MAGIm8WU4vRo8RhFv1UYtZD INWOtS24SMMW0tLnBt5oZYzOjj0KiG7S3j+hYwsYiifL5dSlPEPJs+rJIjM22Fpw/q wYUm5pZaJxU9jcScUxED86Rx+QTEjoRIN+iB2tSFqS6y6PUdeaU5NtphIlgGWR3Ld2 2g7Wax85rKNNiRFmPcPZYRpe9l4zZ9pSX+1HAUJyJaQEAt3w7Ch3zovn0myUcpFUoe mzOla/x/79qtA== Sender: linux-block-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-block@vger.kernel.org 1. Convert from get_user_pages() to pin_user_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] 3. Release each page in mem->hpages[] (instead of mem->hpas[]), because that is the array that pin_longterm_pages() filled in. This is more accurate and should be a little safer from a maintenance point of view. [1] https://lore.kernel.org/r/20190723153640.GB720@lst.de Signed-off-by: John Hubbard --- arch/powerpc/mm/book3s64/iommu_api.c | 12 +++++------- 1 file changed, 5 insertions(+), 7 deletions(-) diff --git a/arch/powerpc/mm/book3s64/iommu_api.c b/arch/powerpc/mm/book3s64/iommu_api.c index 56cc84520577..196383e8e5a9 100644 --- a/arch/powerpc/mm/book3s64/iommu_api.c +++ b/arch/powerpc/mm/book3s64/iommu_api.c @@ -103,7 +103,7 @@ static long mm_iommu_do_alloc(struct mm_struct *mm, unsigned long ua, for (entry = 0; entry < entries; entry += chunk) { unsigned long n = min(entries - entry, chunk); - ret = get_user_pages(ua + (entry << PAGE_SHIFT), n, + ret = pin_user_pages(ua + (entry << PAGE_SHIFT), n, FOLL_WRITE | FOLL_LONGTERM, mem->hpages + entry, NULL); if (ret == n) { @@ -167,9 +167,8 @@ static long mm_iommu_do_alloc(struct mm_struct *mm, unsigned long ua, return 0; free_exit: - /* free the reference taken */ - for (i = 0; i < pinned; i++) - put_page(mem->hpages[i]); + /* free the references taken */ + put_user_pages(mem->hpages, pinned); vfree(mem->hpas); kfree(mem); @@ -212,10 +211,9 @@ static void mm_iommu_unpin(struct mm_iommu_table_group_mem_t *mem) if (!page) continue; - if (mem->hpas[i] & MM_IOMMU_TABLE_GROUP_PAGE_DIRTY) - SetPageDirty(page); + put_user_pages_dirty_lock(&mem->hpages[i], 1, + MM_IOMMU_TABLE_GROUP_PAGE_DIRTY); - put_page(page); mem->hpas[i] = 0; } }