From patchwork Mon Nov 7 16:17:33 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: David Hildenbrand X-Patchwork-Id: 13034771 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id DB638C41535 for ; Mon, 7 Nov 2022 16:21:13 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231589AbiKGQVL (ORCPT ); Mon, 7 Nov 2022 11:21:11 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:43256 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232343AbiKGQUg (ORCPT ); Mon, 7 Nov 2022 11:20:36 -0500 Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.129.124]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 98A892180A for ; Mon, 7 Nov 2022 08:19:06 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1667837945; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=LbhWMksFg92TvneJpw63HzjZ0ts0JOlA6/0p1P82RzY=; b=RglxiRMj8vF/xyaynGAafzEfsKnGMZmQW1mzfl89xlVstKCJ6sxj3ufM5H+i9ubwI4HBvX Xgsg/tQCkmgUzj3c3lGkmo4W+NB5QL8iwdJfMPNFKpWGbnRGwpLH/ro4mSQXWdQNBlRbWF 8f2kjMlHyDZdGfFbkzW5E63maxEYsLc= Received: from mimecast-mx02.redhat.com (mx3-rdu2.redhat.com [66.187.233.73]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id us-mta-351-PsxgEmEyNl6QUqdm8Zp_Iw-1; Mon, 07 Nov 2022 11:19:01 -0500 X-MC-Unique: PsxgEmEyNl6QUqdm8Zp_Iw-1 Received: from smtp.corp.redhat.com (int-mx09.intmail.prod.int.rdu2.redhat.com [10.11.54.9]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx02.redhat.com (Postfix) with ESMTPS id D35F01C09044; Mon, 7 Nov 2022 16:18:58 +0000 (UTC) Received: from t480s.redhat.com (unknown [10.39.195.106]) by smtp.corp.redhat.com (Postfix) with ESMTP id B43784B4010; Mon, 7 Nov 2022 16:18:52 +0000 (UTC) From: David Hildenbrand To: linux-kernel@vger.kernel.org Cc: linux-mm@kvack.org, etnaviv@lists.freedesktop.org, dri-devel@lists.freedesktop.org, linux-arm-kernel@lists.infradead.org, linux-samsung-soc@vger.kernel.org, linux-rdma@vger.kernel.org, linux-media@vger.kernel.org, linux-kselftest@vger.kernel.org, David Hildenbrand , Linus Torvalds , Andrew Morton , Jason Gunthorpe , John Hubbard , Peter Xu , Greg Kroah-Hartman , Andrea Arcangeli , Hugh Dickins , Nadav Amit , Vlastimil Babka , Matthew Wilcox , Mike Kravetz , Muchun Song , Lucas Stach , David Airlie , Oded Gabbay , Arnd Bergmann , Bernard Metzler , Leon Romanovsky Subject: [PATCH RFC 12/19] RDMA/siw: remove FOLL_FORCE usage Date: Mon, 7 Nov 2022 17:17:33 +0100 Message-Id: <20221107161740.144456-13-david@redhat.com> In-Reply-To: <20221107161740.144456-1-david@redhat.com> References: <20221107161740.144456-1-david@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 3.1 on 10.11.54.9 Precedence: bulk List-ID: X-Mailing-List: linux-rdma@vger.kernel.org GUP now supports reliable R/O long-term pinning in COW mappings, such that we break COW early. MAP_SHARED VMAs only use the shared zeropage so far in one corner case (DAXFS file with holes), which can be ignored because GUP does not support long-term pinning in fsdax (see check_vma_flags()). Consequently, FOLL_FORCE | FOLL_WRITE | FOLL_LONGTERM is no longer required for reliable R/O long-term pinning: FOLL_LONGTERM is sufficient. So stop using FOLL_FORCE, which is really only for debugger access. Cc: Bernard Metzler Cc: Jason Gunthorpe Cc: Leon Romanovsky Signed-off-by: David Hildenbrand --- drivers/infiniband/sw/siw/siw_mem.c | 9 ++++----- 1 file changed, 4 insertions(+), 5 deletions(-) diff --git a/drivers/infiniband/sw/siw/siw_mem.c b/drivers/infiniband/sw/siw/siw_mem.c index 61c17db70d65..b2b33dd3b4fa 100644 --- a/drivers/infiniband/sw/siw/siw_mem.c +++ b/drivers/infiniband/sw/siw/siw_mem.c @@ -368,7 +368,7 @@ struct siw_umem *siw_umem_get(u64 start, u64 len, bool writable) struct mm_struct *mm_s; u64 first_page_va; unsigned long mlock_limit; - unsigned int foll_flags = FOLL_WRITE; + unsigned int foll_flags = FOLL_LONGTERM; int num_pages, num_chunks, i, rv = 0; if (!can_do_mlock()) @@ -391,8 +391,8 @@ struct siw_umem *siw_umem_get(u64 start, u64 len, bool writable) mmgrab(mm_s); - if (!writable) - foll_flags |= FOLL_FORCE; + if (writable) + foll_flags |= FOLL_WRITE; mmap_read_lock(mm_s); @@ -423,8 +423,7 @@ struct siw_umem *siw_umem_get(u64 start, u64 len, bool writable) while (nents) { struct page **plist = &umem->page_chunk[i].plist[got]; - rv = pin_user_pages(first_page_va, nents, - foll_flags | FOLL_LONGTERM, + rv = pin_user_pages(first_page_va, nents, foll_flags, plist, NULL); if (rv < 0) goto out_sem_up;