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=-8.2 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS, URIBL_BLOCKED,USER_AGENT_SANE_1 autolearn=unavailable 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 7A64EC43603 for ; Wed, 11 Dec 2019 10:42:49 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 56D6A2054F for ; Wed, 11 Dec 2019 10:42:49 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729004AbfLKKmn (ORCPT ); Wed, 11 Dec 2019 05:42:43 -0500 Received: from mx2.suse.de ([195.135.220.15]:59588 "EHLO mx1.suse.de" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1728030AbfLKKmn (ORCPT ); Wed, 11 Dec 2019 05:42:43 -0500 X-Virus-Scanned: by amavisd-new at test-mx.suse.de Received: from relay2.suse.de (unknown [195.135.220.254]) by mx1.suse.de (Postfix) with ESMTP id D483FB178; Wed, 11 Dec 2019 10:42:38 +0000 (UTC) Received: by quack2.suse.cz (Postfix, from userid 1000) id F3EB81E0B23; Wed, 11 Dec 2019 11:42:36 +0100 (CET) Date: Wed, 11 Dec 2019 11:42:36 +0100 From: Jan Kara To: John Hubbard Cc: Andrew Morton , Al Viro , Alex Williamson , Benjamin Herrenschmidt , =?iso-8859-1?Q?Bj=F6rn_T=F6pel?= , Christoph Hellwig , Dan Williams , Daniel Vetter , Dave Chinner , David Airlie , "David S . Miller" , Ira Weiny , Jan Kara , Jason Gunthorpe , Jens Axboe , Jonathan Corbet , =?iso-8859-1?B?Suly9G1l?= Glisse , Magnus Karlsson , Mauro Carvalho Chehab , Michael Ellerman , Michal Hocko , Mike Kravetz , Paul Mackerras , Shuah Khan , Vlastimil Babka , bpf@vger.kernel.org, dri-devel@lists.freedesktop.org, kvm@vger.kernel.org, linux-block@vger.kernel.org, linux-doc@vger.kernel.org, linux-fsdevel@vger.kernel.org, linux-kselftest@vger.kernel.org, linux-media@vger.kernel.org, linux-rdma@vger.kernel.org, linuxppc-dev@lists.ozlabs.org, netdev@vger.kernel.org, linux-mm@kvack.org, LKML Subject: Re: [PATCH v9 20/25] powerpc: book3s64: convert to pin_user_pages() and put_user_page() Message-ID: <20191211104236.GM1551@quack2.suse.cz> References: <20191211025318.457113-1-jhubbard@nvidia.com> <20191211025318.457113-21-jhubbard@nvidia.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20191211025318.457113-21-jhubbard@nvidia.com> User-Agent: Mutt/1.10.1 (2018-07-13) Sender: linux-rdma-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-rdma@vger.kernel.org On Tue 10-12-19 18:53:13, John Hubbard wrote: > 1. Convert from get_user_pages() to pin_user_pages(). > > 2. As required by pin_user_pages(), release these pages via > put_user_page(). > > Cc: Jan Kara > Signed-off-by: John Hubbard The patch looks good to me. You can add: Reviewed-by: Jan Kara I'd just note that mm_iommu_do_alloc() has a pre-existing bug that the last jump to 'free_exit' (at line 157) happens already after converting page pointers to physical addresses so put_page() calls there will just crash. But that's completely unrelated to your change. I'll send a fix separately. Honza > --- > arch/powerpc/mm/book3s64/iommu_api.c | 10 +++++----- > 1 file changed, 5 insertions(+), 5 deletions(-) > > diff --git a/arch/powerpc/mm/book3s64/iommu_api.c b/arch/powerpc/mm/book3s64/iommu_api.c > index 56cc84520577..a86547822034 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); > @@ -215,7 +214,8 @@ static void mm_iommu_unpin(struct mm_iommu_table_group_mem_t *mem) > if (mem->hpas[i] & MM_IOMMU_TABLE_GROUP_PAGE_DIRTY) > SetPageDirty(page); > > - put_page(page); > + put_user_page(page); > + > mem->hpas[i] = 0; > } > } > -- > 2.24.0 > -- Jan Kara SUSE Labs, CR