From mboxrd@z Thu Jan 1 00:00:00 1970 From: David Hildenbrand Subject: [PATCH mm-unstable v1 10/20] RDMA/umem: remove FOLL_FORCE usage Date: Wed, 16 Nov 2022 11:26:49 +0100 Message-ID: <20221116102659.70287-11-david@redhat.com> References: <20221116102659.70287-1-david@redhat.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender: Content-Transfer-Encoding:Content-Type:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:MIME-Version:References:In-Reply-To: Message-Id:Date:Subject:Cc:To:From:Reply-To:Content-ID:Content-Description: Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Owner; bh=z0IxQKTR30iA3+Evq6O440Uy4KbgALxiaMETu9e4MNo=; b=jH8dR2/2RMk+dV wUFj8J5vfyNHfWJhQW6PjqRQb9BeWF8SEf/cygHU7Pyiqr1rTeQET/Ywz/xLjT4vb9+a9SLAob34T 1PCSaKzYUfOVT9l3DGAS0Rfedo/fG/PGqwxkAG3nYugV/1yDZ4o7dmyokBBOarkS7KAeqjZoS+0LH 1rxACfogYIIckhB8kSEBnaRZVTgbwZzyjOjRrkWwbYEBMsllKKvK8vXiYrpZpn+Z3OSYFEVamj1X7 nWiGXQEhnxf8Dv+C/+3A4TOxK0Q1Aex5TheHYbOX/iR+g/Giqf0MEYG81Z9YM8LD5Q8xSSpUHPBwH c4r4SOeRIryG+7p5xj+w==; DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1668594524; 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=xyj8jS+C9wqOk3KceDQTo75wMiWZgljnGSBlM8HQloY=; b=HyVSO6OqC/gyAIUuVMXoeM1X2q2HGXEdNdaxMdk2Vy95oyYuYPYs+2QP7j1mdL7FrioHdX TbTBqLLcuZ5eaT45BNKl7jbv+D65zT6ecgXqA8ct3duF5iZHVlUxfGqv+aN60svjE9SLxy 2lfc7aOUpVzBnsMZbN7Cm+/iLDmyMoE= In-Reply-To: <20221116102659.70287-1-david@redhat.com> List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-um" Errors-To: linux-um-bounces+glud-user-mode-linux-devel=m.gmane-mx.org@lists.infradead.org To: linux-kernel@vger.kernel.org Cc: x86@kernel.org, linux-alpha@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-ia64@vger.kernel.org, linux-mips@vger.kernel.org, linuxppc-dev@lists.ozlabs.org, sparclinux@vger.kernel.org, linux-um@lists.infradead.org, etnaviv@lists.freedesktop.org, dri-devel@lists.freedesktop.org, linux-samsung-soc@vger.kernel.org, linux-rdma@vger.kernel.org, linux-media@vger.kernel.org, linux-fsdevel@vger.kernel.org, linux-mm@kvack.org, linux-perf-users@vger.kernel.org, linux-security-module@vger.kernel.org, linux-kselftest@vger.kernel.org, Linus Torvalds , Andrew Morton , Jason Gunthorpe , John Hubbard , Peter Xu , Greg Kroah-Hartman , Andrea Arcangeli , Hugh Dickins , Nadav Amit <> 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 ptrace access. Tested-by: Leon Romanovsky # Over mlx4 and mlx5. Cc: Jason Gunthorpe Cc: Leon Romanovsky Signed-off-by: David Hildenbrand --- drivers/infiniband/core/umem.c | 8 ++++---- 1 file changed, 4 insertions(+), 4 deletions(-) diff --git a/drivers/infiniband/core/umem.c b/drivers/infiniband/core/umem.c index 86d479772fbc..755a9c57db6f 100644 --- a/drivers/infiniband/core/umem.c +++ b/drivers/infiniband/core/umem.c @@ -156,7 +156,7 @@ struct ib_umem *ib_umem_get(struct ib_device *device, unsigned long addr, struct mm_struct *mm; unsigned long npages; int pinned, ret; - unsigned int gup_flags = FOLL_WRITE; + unsigned int gup_flags = FOLL_LONGTERM; /* * If the combination of the addr and size requested for this memory @@ -210,8 +210,8 @@ struct ib_umem *ib_umem_get(struct ib_device *device, unsigned long addr, cur_base = addr & PAGE_MASK; - if (!umem->writable) - gup_flags |= FOLL_FORCE; + if (umem->writable) + gup_flags |= FOLL_WRITE; while (npages) { cond_resched(); @@ -219,7 +219,7 @@ struct ib_umem *ib_umem_get(struct ib_device *device, unsigned long addr, min_t(unsigned long, npages, PAGE_SIZE / sizeof(struct page *)), - gup_flags | FOLL_LONGTERM, page_list); + gup_flags, page_list); if (pinned < 0) { ret = pinned; goto umem_release; -- 2.38.1 From mboxrd@z Thu Jan 1 00:00:00 1970 From: David Hildenbrand Date: Wed, 16 Nov 2022 10:26:49 +0000 Subject: [PATCH mm-unstable v1 10/20] RDMA/umem: remove FOLL_FORCE usage Message-Id: <20221116102659.70287-11-david@redhat.com> List-Id: References: <20221116102659.70287-1-david@redhat.com> In-Reply-To: <20221116102659.70287-1-david@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: linux-kernel@vger.kernel.org Cc: x86@kernel.org, linux-alpha@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-ia64@vger.kernel.org, linux-mips@vger.kernel.org, linuxppc-dev@lists.ozlabs.org, sparclinux@vger.kernel.org, linux-um@lists.infradead.org, etnaviv@lists.freedesktop.org, dri-devel@lists.freedesktop.org, linux-samsung-soc@vger.kernel.org, linux-rdma@vger.kernel.org, linux-media@vger.kernel.org, linux-fsdevel@vger.kernel.org, linux-mm@kvack.org, linux-perf-users@vger.kernel.org, linux-security-module@vger.kernel.org, linux-kselftest@vger.kernel.org, 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 , Shuah Khan , Lucas Stach , David Airlie , Oded Gabbay , Arnd Bergmann , Christoph Hellwig , Alex Williamson , David Hildenbrand , Leon Romanovsky , Leon Romanovsky 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 ptrace access. Tested-by: Leon Romanovsky # Over mlx4 and mlx5. Cc: Jason Gunthorpe Cc: Leon Romanovsky Signed-off-by: David Hildenbrand --- drivers/infiniband/core/umem.c | 8 ++++---- 1 file changed, 4 insertions(+), 4 deletions(-) diff --git a/drivers/infiniband/core/umem.c b/drivers/infiniband/core/umem.c index 86d479772fbc..755a9c57db6f 100644 --- a/drivers/infiniband/core/umem.c +++ b/drivers/infiniband/core/umem.c @@ -156,7 +156,7 @@ struct ib_umem *ib_umem_get(struct ib_device *device, unsigned long addr, struct mm_struct *mm; unsigned long npages; int pinned, ret; - unsigned int gup_flags = FOLL_WRITE; + unsigned int gup_flags = FOLL_LONGTERM; /* * If the combination of the addr and size requested for this memory @@ -210,8 +210,8 @@ struct ib_umem *ib_umem_get(struct ib_device *device, unsigned long addr, cur_base = addr & PAGE_MASK; - if (!umem->writable) - gup_flags |= FOLL_FORCE; + if (umem->writable) + gup_flags |= FOLL_WRITE; while (npages) { cond_resched(); @@ -219,7 +219,7 @@ struct ib_umem *ib_umem_get(struct ib_device *device, unsigned long addr, min_t(unsigned long, npages, PAGE_SIZE / sizeof(struct page *)), - gup_flags | FOLL_LONGTERM, page_list); + gup_flags, page_list); if (pinned < 0) { ret = pinned; goto umem_release; -- 2.38.1 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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 586D6C43217 for ; Wed, 16 Nov 2022 10:37:46 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S233765AbiKPKhV (ORCPT ); Wed, 16 Nov 2022 05:37:21 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:43818 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229582AbiKPKfm (ORCPT ); Wed, 16 Nov 2022 05:35:42 -0500 Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.133.124]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 60D3EE0A2 for ; Wed, 16 Nov 2022 02:28:41 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1668594520; 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=xyj8jS+C9wqOk3KceDQTo75wMiWZgljnGSBlM8HQloY=; b=PU1G9itrKgbnNgXnIc0M26uwEdmbd83zbKEUH8b7eYKPxcTJiyLkwVYqM2xRxrxdWZ6j2h 0rKjSBUkltSVMaHO7VKQn3ELKQ85s+haMnW6nAm0sILxwpab8C/KkLZuSTn6ok0+427Ap/ pDHQvSDcsDRpn1TnWoz2mP8BUswFqd0= Received: from mimecast-mx02.redhat.com (mimecast-mx02.redhat.com [66.187.233.88]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id us-mta-156-1i0B0n5wO9KbojDzH-noSA-1; Wed, 16 Nov 2022 05:28:39 -0500 X-MC-Unique: 1i0B0n5wO9KbojDzH-noSA-1 Received: from smtp.corp.redhat.com (int-mx04.intmail.prod.int.rdu2.redhat.com [10.11.54.4]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx02.redhat.com (Postfix) with ESMTPS id 6CE1B86F132; Wed, 16 Nov 2022 10:28:37 +0000 (UTC) Received: from t480s.fritz.box (unknown [10.39.193.216]) by smtp.corp.redhat.com (Postfix) with ESMTP id D7D7C2028E8F; Wed, 16 Nov 2022 10:28:29 +0000 (UTC) From: David Hildenbrand To: linux-kernel@vger.kernel.org Cc: x86@kernel.org, linux-alpha@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-ia64@vger.kernel.org, linux-mips@vger.kernel.org, linuxppc-dev@lists.ozlabs.org, sparclinux@vger.kernel.org, linux-um@lists.infradead.org, etnaviv@lists.freedesktop.org, dri-devel@lists.freedesktop.org, linux-samsung-soc@vger.kernel.org, linux-rdma@vger.kernel.org, linux-media@vger.kernel.org, linux-fsdevel@vger.kernel.org, linux-mm@kvack.org, linux-perf-users@vger.kernel.org, linux-security-module@vger.kernel.org, linux-kselftest@vger.kernel.org, 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 , Shuah Khan , Lucas Stach , David Airlie , Oded Gabbay , Arnd Bergmann , Christoph Hellwig , Alex Williamson , David Hildenbrand , Leon Romanovsky , Leon Romanovsky Subject: [PATCH mm-unstable v1 10/20] RDMA/umem: remove FOLL_FORCE usage Date: Wed, 16 Nov 2022 11:26:49 +0100 Message-Id: <20221116102659.70287-11-david@redhat.com> In-Reply-To: <20221116102659.70287-1-david@redhat.com> References: <20221116102659.70287-1-david@redhat.com> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Scanned-By: MIMEDefang 3.1 on 10.11.54.4 Precedence: bulk List-ID: X-Mailing-List: linux-kselftest@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 ptrace access. Tested-by: Leon Romanovsky # Over mlx4 and mlx5. Cc: Jason Gunthorpe Cc: Leon Romanovsky Signed-off-by: David Hildenbrand --- drivers/infiniband/core/umem.c | 8 ++++---- 1 file changed, 4 insertions(+), 4 deletions(-) diff --git a/drivers/infiniband/core/umem.c b/drivers/infiniband/core/umem.c index 86d479772fbc..755a9c57db6f 100644 --- a/drivers/infiniband/core/umem.c +++ b/drivers/infiniband/core/umem.c @@ -156,7 +156,7 @@ struct ib_umem *ib_umem_get(struct ib_device *device, unsigned long addr, struct mm_struct *mm; unsigned long npages; int pinned, ret; - unsigned int gup_flags = FOLL_WRITE; + unsigned int gup_flags = FOLL_LONGTERM; /* * If the combination of the addr and size requested for this memory @@ -210,8 +210,8 @@ struct ib_umem *ib_umem_get(struct ib_device *device, unsigned long addr, cur_base = addr & PAGE_MASK; - if (!umem->writable) - gup_flags |= FOLL_FORCE; + if (umem->writable) + gup_flags |= FOLL_WRITE; while (npages) { cond_resched(); @@ -219,7 +219,7 @@ struct ib_umem *ib_umem_get(struct ib_device *device, unsigned long addr, min_t(unsigned long, npages, PAGE_SIZE / sizeof(struct page *)), - gup_flags | FOLL_LONGTERM, page_list); + gup_flags, page_list); if (pinned < 0) { ret = pinned; goto umem_release; -- 2.38.1 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 Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 954A3C4167B for ; Wed, 16 Nov 2022 10:32:58 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender: Content-Transfer-Encoding:Content-Type:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:MIME-Version:References:In-Reply-To: Message-Id:Date:Subject:Cc:To:From:Reply-To:Content-ID:Content-Description: Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Owner; bh=z0IxQKTR30iA3+Evq6O440Uy4KbgALxiaMETu9e4MNo=; b=jH8dR2/2RMk+dV wUFj8J5vfyNHfWJhQW6PjqRQb9BeWF8SEf/cygHU7Pyiqr1rTeQET/Ywz/xLjT4vb9+a9SLAob34T 1PCSaKzYUfOVT9l3DGAS0Rfedo/fG/PGqwxkAG3nYugV/1yDZ4o7dmyokBBOarkS7KAeqjZoS+0LH 1rxACfogYIIckhB8kSEBnaRZVTgbwZzyjOjRrkWwbYEBMsllKKvK8vXiYrpZpn+Z3OSYFEVamj1X7 nWiGXQEhnxf8Dv+C/+3A4TOxK0Q1Aex5TheHYbOX/iR+g/Giqf0MEYG81Z9YM8LD5Q8xSSpUHPBwH c4r4SOeRIryG+7p5xj+w==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.94.2 #2 (Red Hat Linux)) id 1ovFiz-002FQM-MV; Wed, 16 Nov 2022 10:32:57 +0000 Received: from us-smtp-delivery-124.mimecast.com ([170.10.133.124]) by bombadil.infradead.org with esmtps (Exim 4.94.2 #2 (Red Hat Linux)) id 1ovFev-002D4Y-BU for linux-um@lists.infradead.org; Wed, 16 Nov 2022 10:28:47 +0000 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1668594524; 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=xyj8jS+C9wqOk3KceDQTo75wMiWZgljnGSBlM8HQloY=; b=HyVSO6OqC/gyAIUuVMXoeM1X2q2HGXEdNdaxMdk2Vy95oyYuYPYs+2QP7j1mdL7FrioHdX TbTBqLLcuZ5eaT45BNKl7jbv+D65zT6ecgXqA8ct3duF5iZHVlUxfGqv+aN60svjE9SLxy 2lfc7aOUpVzBnsMZbN7Cm+/iLDmyMoE= Received: from mimecast-mx02.redhat.com (mimecast-mx02.redhat.com [66.187.233.88]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id us-mta-156-1i0B0n5wO9KbojDzH-noSA-1; Wed, 16 Nov 2022 05:28:39 -0500 X-MC-Unique: 1i0B0n5wO9KbojDzH-noSA-1 Received: from smtp.corp.redhat.com (int-mx04.intmail.prod.int.rdu2.redhat.com [10.11.54.4]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx02.redhat.com (Postfix) with ESMTPS id 6CE1B86F132; Wed, 16 Nov 2022 10:28:37 +0000 (UTC) Received: from t480s.fritz.box (unknown [10.39.193.216]) by smtp.corp.redhat.com (Postfix) with ESMTP id D7D7C2028E8F; Wed, 16 Nov 2022 10:28:29 +0000 (UTC) From: David Hildenbrand To: linux-kernel@vger.kernel.org Cc: x86@kernel.org, linux-alpha@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-ia64@vger.kernel.org, linux-mips@vger.kernel.org, linuxppc-dev@lists.ozlabs.org, sparclinux@vger.kernel.org, linux-um@lists.infradead.org, etnaviv@lists.freedesktop.org, dri-devel@lists.freedesktop.org, linux-samsung-soc@vger.kernel.org, linux-rdma@vger.kernel.org, linux-media@vger.kernel.org, linux-fsdevel@vger.kernel.org, linux-mm@kvack.org, linux-perf-users@vger.kernel.org, linux-security-module@vger.kernel.org, linux-kselftest@vger.kernel.org, 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 , Shuah Khan , Lucas Stach , David Airlie , Oded Gabbay , Arnd Bergmann , Christoph Hellwig , Alex Williamson , David Hildenbrand , Leon Romanovsky , Leon Romanovsky Subject: [PATCH mm-unstable v1 10/20] RDMA/umem: remove FOLL_FORCE usage Date: Wed, 16 Nov 2022 11:26:49 +0100 Message-Id: <20221116102659.70287-11-david@redhat.com> In-Reply-To: <20221116102659.70287-1-david@redhat.com> References: <20221116102659.70287-1-david@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 3.1 on 10.11.54.4 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20221116_022845_494849_E86C955B X-CRM114-Status: GOOD ( 14.95 ) X-BeenThere: linux-um@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "linux-um" Errors-To: linux-um-bounces+linux-um=archiver.kernel.org@lists.infradead.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 ptrace access. Tested-by: Leon Romanovsky # Over mlx4 and mlx5. Cc: Jason Gunthorpe Cc: Leon Romanovsky Signed-off-by: David Hildenbrand --- drivers/infiniband/core/umem.c | 8 ++++---- 1 file changed, 4 insertions(+), 4 deletions(-) diff --git a/drivers/infiniband/core/umem.c b/drivers/infiniband/core/umem.c index 86d479772fbc..755a9c57db6f 100644 --- a/drivers/infiniband/core/umem.c +++ b/drivers/infiniband/core/umem.c @@ -156,7 +156,7 @@ struct ib_umem *ib_umem_get(struct ib_device *device, unsigned long addr, struct mm_struct *mm; unsigned long npages; int pinned, ret; - unsigned int gup_flags = FOLL_WRITE; + unsigned int gup_flags = FOLL_LONGTERM; /* * If the combination of the addr and size requested for this memory @@ -210,8 +210,8 @@ struct ib_umem *ib_umem_get(struct ib_device *device, unsigned long addr, cur_base = addr & PAGE_MASK; - if (!umem->writable) - gup_flags |= FOLL_FORCE; + if (umem->writable) + gup_flags |= FOLL_WRITE; while (npages) { cond_resched(); @@ -219,7 +219,7 @@ struct ib_umem *ib_umem_get(struct ib_device *device, unsigned long addr, min_t(unsigned long, npages, PAGE_SIZE / sizeof(struct page *)), - gup_flags | FOLL_LONGTERM, page_list); + gup_flags, page_list); if (pinned < 0) { ret = pinned; goto umem_release; -- 2.38.1 _______________________________________________ linux-um mailing list linux-um@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-um 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 Received: from lists.ozlabs.org (lists.ozlabs.org [112.213.38.117]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id E7AFBC4332F for ; Wed, 16 Nov 2022 10:36:47 +0000 (UTC) Received: from boromir.ozlabs.org (localhost [IPv6:::1]) by lists.ozlabs.org (Postfix) with ESMTP id 4NBzxV0V1fz3f65 for ; Wed, 16 Nov 2022 21:36:46 +1100 (AEDT) Authentication-Results: lists.ozlabs.org; dkim=fail reason="signature verification failed" (1024-bit key; unprotected) header.d=redhat.com header.i=@redhat.com header.a=rsa-sha256 header.s=mimecast20190719 header.b=HyVSO6Oq; dkim=fail reason="signature verification failed" (1024-bit key) header.d=redhat.com header.i=@redhat.com header.a=rsa-sha256 header.s=mimecast20190719 header.b=BnVUZyRH; dkim-atps=neutral Authentication-Results: lists.ozlabs.org; spf=pass (sender SPF authorized) smtp.mailfrom=redhat.com (client-ip=170.10.133.124; helo=us-smtp-delivery-124.mimecast.com; envelope-from=david@redhat.com; receiver=) Authentication-Results: lists.ozlabs.org; dkim=pass (1024-bit key; unprotected) header.d=redhat.com header.i=@redhat.com header.a=rsa-sha256 header.s=mimecast20190719 header.b=HyVSO6Oq; dkim=pass (1024-bit key) header.d=redhat.com header.i=@redhat.com header.a=rsa-sha256 header.s=mimecast20190719 header.b=BnVUZyRH; dkim-atps=neutral Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.133.124]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits) server-digest SHA256) (No client certificate requested) by lists.ozlabs.org (Postfix) with ESMTPS id 4NBzmH1VLmz3dvD for ; Wed, 16 Nov 2022 21:28:46 +1100 (AEDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1668594524; 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=xyj8jS+C9wqOk3KceDQTo75wMiWZgljnGSBlM8HQloY=; b=HyVSO6OqC/gyAIUuVMXoeM1X2q2HGXEdNdaxMdk2Vy95oyYuYPYs+2QP7j1mdL7FrioHdX TbTBqLLcuZ5eaT45BNKl7jbv+D65zT6ecgXqA8ct3duF5iZHVlUxfGqv+aN60svjE9SLxy 2lfc7aOUpVzBnsMZbN7Cm+/iLDmyMoE= DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1668594525; 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=xyj8jS+C9wqOk3KceDQTo75wMiWZgljnGSBlM8HQloY=; b=BnVUZyRHK+4hkdUyHoKp3oVDJxdrX4eDGvyeXVFJUyGQpD95iMuvxXfNZKgeD2zck2oAk/ 8ljOvYQFRr1etK1xmw8+L3K/35RmeBw6u8dCHj8givBe8MP8iU0AZVH/Z0pivNwQogOTsV txlplTPPPjredz0HO5NtMvkDgm8Dtg4= Received: from mimecast-mx02.redhat.com (mimecast-mx02.redhat.com [66.187.233.88]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id us-mta-156-1i0B0n5wO9KbojDzH-noSA-1; Wed, 16 Nov 2022 05:28:39 -0500 X-MC-Unique: 1i0B0n5wO9KbojDzH-noSA-1 Received: from smtp.corp.redhat.com (int-mx04.intmail.prod.int.rdu2.redhat.com [10.11.54.4]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx02.redhat.com (Postfix) with ESMTPS id 6CE1B86F132; Wed, 16 Nov 2022 10:28:37 +0000 (UTC) Received: from t480s.fritz.box (unknown [10.39.193.216]) by smtp.corp.redhat.com (Postfix) with ESMTP id D7D7C2028E8F; Wed, 16 Nov 2022 10:28:29 +0000 (UTC) From: David Hildenbrand To: linux-kernel@vger.kernel.org Subject: [PATCH mm-unstable v1 10/20] RDMA/umem: remove FOLL_FORCE usage Date: Wed, 16 Nov 2022 11:26:49 +0100 Message-Id: <20221116102659.70287-11-david@redhat.com> In-Reply-To: <20221116102659.70287-1-david@redhat.com> References: <20221116102659.70287-1-david@redhat.com> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Scanned-By: MIMEDefang 3.1 on 10.11.54.4 X-BeenThere: linuxppc-dev@lists.ozlabs.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: linux-ia64@vger.kernel.org, Greg Kroah-Hartman , David Hildenbrand , dri-devel@lists.freedesktop.org, linux-mm@kvack.org, Nadav Amit , linux-kselftest@vger.kernel.org, sparclinux@vger.kernel.org, Shuah Khan , Andrea Arcangeli , linux-samsung-soc@vger.kernel.org, Leon Romanovsky , linux-rdma@vger.kernel.org, David Airlie , x86@kernel.org, Hugh Dickins , Matthew Wilcox , Christoph Hellwig , Jason Gunthorpe , Vlastimil Babka , linux-media@vger.kernel.org, Arnd Bergmann , John Hubbard , linux-um@lists.infradead.org, etnaviv@lists.freedesktop.org, Alex Williamson , Peter Xu , Muchun Song , linux-arm-kernel@lists.infradead.org, linuxppc-dev@lists.ozlabs.or g, Oded Gabbay , linux-mips@vger.kernel.org, linux-perf-users@vger.kernel.org, linux-security-module@vger.kernel.org, linux-alpha@vger.kernel.org, linux-fsdevel@vger.kernel.org, Andrew Morton , Lucas Stach , Linus Torvalds , Leon Romanovsky , Mike Kravetz Errors-To: linuxppc-dev-bounces+linuxppc-dev=archiver.kernel.org@lists.ozlabs.org Sender: "Linuxppc-dev" 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 ptrace access. Tested-by: Leon Romanovsky # Over mlx4 and mlx5. Cc: Jason Gunthorpe Cc: Leon Romanovsky Signed-off-by: David Hildenbrand --- drivers/infiniband/core/umem.c | 8 ++++---- 1 file changed, 4 insertions(+), 4 deletions(-) diff --git a/drivers/infiniband/core/umem.c b/drivers/infiniband/core/umem.c index 86d479772fbc..755a9c57db6f 100644 --- a/drivers/infiniband/core/umem.c +++ b/drivers/infiniband/core/umem.c @@ -156,7 +156,7 @@ struct ib_umem *ib_umem_get(struct ib_device *device, unsigned long addr, struct mm_struct *mm; unsigned long npages; int pinned, ret; - unsigned int gup_flags = FOLL_WRITE; + unsigned int gup_flags = FOLL_LONGTERM; /* * If the combination of the addr and size requested for this memory @@ -210,8 +210,8 @@ struct ib_umem *ib_umem_get(struct ib_device *device, unsigned long addr, cur_base = addr & PAGE_MASK; - if (!umem->writable) - gup_flags |= FOLL_FORCE; + if (umem->writable) + gup_flags |= FOLL_WRITE; while (npages) { cond_resched(); @@ -219,7 +219,7 @@ struct ib_umem *ib_umem_get(struct ib_device *device, unsigned long addr, min_t(unsigned long, npages, PAGE_SIZE / sizeof(struct page *)), - gup_flags | FOLL_LONGTERM, page_list); + gup_flags, page_list); if (pinned < 0) { ret = pinned; goto umem_release; -- 2.38.1 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 Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 8C227C4332F for ; Wed, 16 Nov 2022 11:46:48 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender: Content-Transfer-Encoding:Content-Type:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:MIME-Version:References:In-Reply-To: Message-Id:Date:Subject:Cc:To:From:Reply-To:Content-ID:Content-Description: Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Owner; bh=CuO6vY18Q1cg/PtnACK51jhGls0I0/vWqNgJ/fRvNbU=; b=lcCWq6Q5Kn1IY8 TFMlLD/2a3g2UEolvYCFiS638bk+FAJahnMr4ZqSi+bacnAwzgC0w+qy4TRpvqNAb/XauzhJRv75L JB9DkillxdqrQX48oecNTpeZrmWucGW3YUdU45PsYkzQosUmOiotFz7GxSAB/fkU+3ESwpBb+52RM +6QDl4sgeEAwznz+kHD4OoBgI8+1hy1xL1EziS2JT/2AOAG4G1Ziscw9W8eL1idvFjGYHYC/Jie0d 9O+t6jj9hXfn4PUIaJPAYqMBjYOD7dTWRrSTlpHHkAZtNr1hBdedM/+zfO127AO1ZnlMRhgoHK88X cfeH9Q07BsGcHmfeXwPg==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.94.2 #2 (Red Hat Linux)) id 1ovGrO-0035GV-57; Wed, 16 Nov 2022 11:45:42 +0000 Received: from us-smtp-delivery-124.mimecast.com ([170.10.133.124]) by bombadil.infradead.org with esmtps (Exim 4.94.2 #2 (Red Hat Linux)) id 1ovFgO-002E6j-QS for linux-arm-kernel@lists.infradead.org; Wed, 16 Nov 2022 10:30:24 +0000 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1668594615; 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=xyj8jS+C9wqOk3KceDQTo75wMiWZgljnGSBlM8HQloY=; b=K+zwqjUbSN1QawrCbmSLu+2ZBH2nfPdtoUHXux0A9qLFKjfYekaNPqGN5PWn/IJmHbXvNf ErnTBPFA9bpgCq+ez329EcnFZmiYUyY+owFKV0P7YbzcZH/cp3S3IRjQF9Unj1+Hzk98hT VbgKFyJYZKQlAwWTHAiL0jwFS4gDs3A= Received: from mimecast-mx02.redhat.com (mimecast-mx02.redhat.com [66.187.233.88]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id us-mta-156-1i0B0n5wO9KbojDzH-noSA-1; Wed, 16 Nov 2022 05:28:39 -0500 X-MC-Unique: 1i0B0n5wO9KbojDzH-noSA-1 Received: from smtp.corp.redhat.com (int-mx04.intmail.prod.int.rdu2.redhat.com [10.11.54.4]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx02.redhat.com (Postfix) with ESMTPS id 6CE1B86F132; Wed, 16 Nov 2022 10:28:37 +0000 (UTC) Received: from t480s.fritz.box (unknown [10.39.193.216]) by smtp.corp.redhat.com (Postfix) with ESMTP id D7D7C2028E8F; Wed, 16 Nov 2022 10:28:29 +0000 (UTC) From: David Hildenbrand To: linux-kernel@vger.kernel.org Cc: x86@kernel.org, linux-alpha@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-ia64@vger.kernel.org, linux-mips@vger.kernel.org, linuxppc-dev@lists.ozlabs.org, sparclinux@vger.kernel.org, linux-um@lists.infradead.org, etnaviv@lists.freedesktop.org, dri-devel@lists.freedesktop.org, linux-samsung-soc@vger.kernel.org, linux-rdma@vger.kernel.org, linux-media@vger.kernel.org, linux-fsdevel@vger.kernel.org, linux-mm@kvack.org, linux-perf-users@vger.kernel.org, linux-security-module@vger.kernel.org, linux-kselftest@vger.kernel.org, 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 , Shuah Khan , Lucas Stach , David Airlie , Oded Gabbay , Arnd Bergmann , Christoph Hellwig , Alex Williamson , David Hildenbrand , Leon Romanovsky , Leon Romanovsky Subject: [PATCH mm-unstable v1 10/20] RDMA/umem: remove FOLL_FORCE usage Date: Wed, 16 Nov 2022 11:26:49 +0100 Message-Id: <20221116102659.70287-11-david@redhat.com> In-Reply-To: <20221116102659.70287-1-david@redhat.com> References: <20221116102659.70287-1-david@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 3.1 on 10.11.54.4 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20221116_023017_048469_67E973D3 X-CRM114-Status: GOOD ( 15.86 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.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 ptrace access. Tested-by: Leon Romanovsky # Over mlx4 and mlx5. Cc: Jason Gunthorpe Cc: Leon Romanovsky Signed-off-by: David Hildenbrand --- drivers/infiniband/core/umem.c | 8 ++++---- 1 file changed, 4 insertions(+), 4 deletions(-) diff --git a/drivers/infiniband/core/umem.c b/drivers/infiniband/core/umem.c index 86d479772fbc..755a9c57db6f 100644 --- a/drivers/infiniband/core/umem.c +++ b/drivers/infiniband/core/umem.c @@ -156,7 +156,7 @@ struct ib_umem *ib_umem_get(struct ib_device *device, unsigned long addr, struct mm_struct *mm; unsigned long npages; int pinned, ret; - unsigned int gup_flags = FOLL_WRITE; + unsigned int gup_flags = FOLL_LONGTERM; /* * If the combination of the addr and size requested for this memory @@ -210,8 +210,8 @@ struct ib_umem *ib_umem_get(struct ib_device *device, unsigned long addr, cur_base = addr & PAGE_MASK; - if (!umem->writable) - gup_flags |= FOLL_FORCE; + if (umem->writable) + gup_flags |= FOLL_WRITE; while (npages) { cond_resched(); @@ -219,7 +219,7 @@ struct ib_umem *ib_umem_get(struct ib_device *device, unsigned long addr, min_t(unsigned long, npages, PAGE_SIZE / sizeof(struct page *)), - gup_flags | FOLL_LONGTERM, page_list); + gup_flags, page_list); if (pinned < 0) { ret = pinned; goto umem_release; -- 2.38.1 _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel 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 Received: from gabe.freedesktop.org (gabe.freedesktop.org [131.252.210.177]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 9F36FC433FE for ; Wed, 16 Nov 2022 10:29:04 +0000 (UTC) Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id 8E2F310E46F; Wed, 16 Nov 2022 10:29:02 +0000 (UTC) Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.133.124]) by gabe.freedesktop.org (Postfix) with ESMTPS id 622CF10E471 for ; Wed, 16 Nov 2022 10:28:43 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1668594522; 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=xyj8jS+C9wqOk3KceDQTo75wMiWZgljnGSBlM8HQloY=; b=g3kH0ed8piHhUNkKCWAbOm7xvoQJ5cCFqIYmh+dC4YUm53jlzb9Se8TnRvxS4G8SgjMEZR llL7uRi7LqwHKucI35e3GUSY0ODFlskpo+gFPEchUNh5Eng8dL4F28mTluvV6D+lYsvv76 RqPkCwGIUI2TXbqPM4b3X/wP0pBzkbI= Received: from mimecast-mx02.redhat.com (mimecast-mx02.redhat.com [66.187.233.88]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id us-mta-156-1i0B0n5wO9KbojDzH-noSA-1; Wed, 16 Nov 2022 05:28:39 -0500 X-MC-Unique: 1i0B0n5wO9KbojDzH-noSA-1 Received: from smtp.corp.redhat.com (int-mx04.intmail.prod.int.rdu2.redhat.com [10.11.54.4]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx02.redhat.com (Postfix) with ESMTPS id 6CE1B86F132; Wed, 16 Nov 2022 10:28:37 +0000 (UTC) Received: from t480s.fritz.box (unknown [10.39.193.216]) by smtp.corp.redhat.com (Postfix) with ESMTP id D7D7C2028E8F; Wed, 16 Nov 2022 10:28:29 +0000 (UTC) From: David Hildenbrand To: linux-kernel@vger.kernel.org Subject: [PATCH mm-unstable v1 10/20] RDMA/umem: remove FOLL_FORCE usage Date: Wed, 16 Nov 2022 11:26:49 +0100 Message-Id: <20221116102659.70287-11-david@redhat.com> In-Reply-To: <20221116102659.70287-1-david@redhat.com> References: <20221116102659.70287-1-david@redhat.com> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Scanned-By: MIMEDefang 3.1 on 10.11.54.4 X-BeenThere: dri-devel@lists.freedesktop.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Direct Rendering Infrastructure - Development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: linux-ia64@vger.kernel.org, Greg Kroah-Hartman , David Hildenbrand , dri-devel@lists.freedesktop.org, linux-mm@kvack.org, Nadav Amit , linux-kselftest@vger.kernel.org, sparclinux@vger.kernel.org, Shuah Khan , Andrea Arcangeli , linux-samsung-soc@vger.kernel.org, Leon Romanovsky , linux-rdma@vger.kernel.org, x86@kernel.org, Hugh Dickins , Matthew Wilcox , Christoph Hellwig , Jason Gunthorpe , Vlastimil Babka , linux-media@vger.kernel.org, Arnd Bergmann , John Hubbard , linux-um@lists.infradead.org, etnaviv@lists.freedesktop.org, Alex Williamson , Peter Xu , Muchun Song , linux-arm-kernel@lists.infradead.org, linuxppc-dev@lists.ozlabs.org, Oded Gabbay , linux-mips@vger.kernel.org, linux-perf-users@vger.kernel.org, linux-security-module@vger.kernel.org, linux-alpha@vger.kernel.org, linux-fsdevel@vger.kernel.org, Andrew Morton , Linus Torvalds , Leon Romanovsky , Mike Kravetz Errors-To: dri-devel-bounces@lists.freedesktop.org Sender: "dri-devel" 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 ptrace access. Tested-by: Leon Romanovsky # Over mlx4 and mlx5. Cc: Jason Gunthorpe Cc: Leon Romanovsky Signed-off-by: David Hildenbrand --- drivers/infiniband/core/umem.c | 8 ++++---- 1 file changed, 4 insertions(+), 4 deletions(-) diff --git a/drivers/infiniband/core/umem.c b/drivers/infiniband/core/umem.c index 86d479772fbc..755a9c57db6f 100644 --- a/drivers/infiniband/core/umem.c +++ b/drivers/infiniband/core/umem.c @@ -156,7 +156,7 @@ struct ib_umem *ib_umem_get(struct ib_device *device, unsigned long addr, struct mm_struct *mm; unsigned long npages; int pinned, ret; - unsigned int gup_flags = FOLL_WRITE; + unsigned int gup_flags = FOLL_LONGTERM; /* * If the combination of the addr and size requested for this memory @@ -210,8 +210,8 @@ struct ib_umem *ib_umem_get(struct ib_device *device, unsigned long addr, cur_base = addr & PAGE_MASK; - if (!umem->writable) - gup_flags |= FOLL_FORCE; + if (umem->writable) + gup_flags |= FOLL_WRITE; while (npages) { cond_resched(); @@ -219,7 +219,7 @@ struct ib_umem *ib_umem_get(struct ib_device *device, unsigned long addr, min_t(unsigned long, npages, PAGE_SIZE / sizeof(struct page *)), - gup_flags | FOLL_LONGTERM, page_list); + gup_flags, page_list); if (pinned < 0) { ret = pinned; goto umem_release; -- 2.38.1