From nobody Wed Feb 11 03:42:06 2026 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 34CC6C77B7D for ; Sun, 14 May 2023 21:27:00 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S233798AbjENV05 (ORCPT ); Sun, 14 May 2023 17:26:57 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:45634 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229534AbjENV0v (ORCPT ); Sun, 14 May 2023 17:26:51 -0400 Received: from mail-wr1-x431.google.com (mail-wr1-x431.google.com [IPv6:2a00:1450:4864:20::431]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 96B44E5A; Sun, 14 May 2023 14:26:49 -0700 (PDT) Received: by mail-wr1-x431.google.com with SMTP id ffacd0b85a97d-3062db220a3so7729894f8f.0; Sun, 14 May 2023 14:26:49 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20221208; t=1684099608; x=1686691608; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:from:to:cc:subject:date :message-id:reply-to; bh=zDRI/SmuJW1MOkHOGv6LoDkcQTN7wDGl7tj3wYSbUK8=; b=sdn5c8JjWfT/id4kBAa2qLnZNzDuFeXXKXgxcLiuPLppaNWdJBOvyxDpS0VFlVludQ uptDi3JKAyFFeJieI45zFd+JYNbT056xyHCT29j/0yOTbU+LcrSMFcc9pRsij0+QeE6L AG2IhZ2UxfA+1xGP8Ce1JqANQZaqVHtk2a8Q0qhbWzxGMtp32DM/XDvP+qb/pthLkgtH B8cdnnioE9cewziKOptRqqjbwbfq9jPJgEsg1XQi50vJEh1hcTypP3mTST/EhQ9nQv7v u8GXlWjDSXOyPjxevErNsh3kIk0VPGA+zC1ai88lFF+/URQmt3mnoKxdV8Cbu7m958DV SNug== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20221208; t=1684099608; x=1686691608; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:x-gm-message-state:from:to:cc :subject:date:message-id:reply-to; bh=zDRI/SmuJW1MOkHOGv6LoDkcQTN7wDGl7tj3wYSbUK8=; b=VZ7K0JjREvrzS0vLu1K6eJIgJWAkra86qNm7WiS/pKwSOXOMTO6fxKe9fsKsseUYd2 G1Ri6BwesRi35FwMBI9LNPBYzZtO3Br4TYnHardUn6P3W3Wjqz42P+MDHXC7EwjGUwwU Y4HO7/guB42L8Em5QKLdaV3YCEHivTQiYLnPfCup0dzHhN271+bpKRgkFdqSn8JVDFgC kVFf8RB6A1jjD3z/9TW+lzq/QorDLF606voH2BGDZscEb6xUoAYJVvIBvO9gu0TZYPXJ nGR5BkslH24wZBqE4MLpCmetwG3XY7pixR6/wrzL+nep7v/nhyMi7QxFsdQnIWXqug1H XRxQ== X-Gm-Message-State: AC+VfDwg9YDWvNRO1SqrcBdQLzaLVOpJxY/w4F8CeAcmJHdke01qNYKA kqPhvjnE9Ec1dw4AldcUWuw= X-Google-Smtp-Source: ACHHUZ7sG7Qk0+WYMTV6b4v9dHtB0zmY4Zy9Nl7tvG7pDojdVP+7xDTkXtnFXvGR7e5uzEeCeZ2TfA== X-Received: by 2002:adf:f491:0:b0:306:31b7:abe4 with SMTP id l17-20020adff491000000b0030631b7abe4mr26212161wro.14.1684099607746; Sun, 14 May 2023 14:26:47 -0700 (PDT) Received: from lucifer.home ([2a00:23c5:dc8c:8701:1663:9a35:5a7b:1d76]) by smtp.googlemail.com with ESMTPSA id o1-20020a5d6701000000b003063a1cdaf2sm30433846wru.48.2023.05.14.14.26.46 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Sun, 14 May 2023 14:26:46 -0700 (PDT) From: Lorenzo Stoakes To: linux-mm@kvack.org, linux-kernel@vger.kernel.org, Andrew Morton Cc: Matthew Wilcox , David Hildenbrand , x86@kernel.org, linux-sgx@vger.kernel.org, amd-gfx@lists.freedesktop.org, dri-devel@lists.freedesktop.org, kvm@vger.kernel.org, Thomas Gleixner , Ingo Molnar , Borislav Petkov , Jarkko Sakkinen , "H . Peter Anvin" , Xinhui Pan , David Airlie , Daniel Vetter , Dimitri Sivanich , Arnd Bergmann , Greg Kroah-Hartman , Paolo Bonzini , Jens Axboe , Pavel Begunkov , Jason Gunthorpe , John Hubbard , Christian Konig , Lorenzo Stoakes , Jason Gunthorpe Subject: [PATCH v5 1/6] mm/gup: remove unused vmas parameter from get_user_pages() Date: Sun, 14 May 2023 22:26:41 +0100 Message-Id: X-Mailer: git-send-email 2.40.1 In-Reply-To: References: MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: quoted-printable Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org No invocation of get_user_pages() use the vmas parameter, so remove it. The GUP API is confusing and caveated. Recent changes have done much to improve that, however there is more we can do. Exporting vmas is a prime target as the caller has to be extremely careful to preclude their use after the mmap_lock has expired or otherwise be left with dangling pointers. Removing the vmas parameter focuses the GUP functions upon their primary purpose - pinning (and outputting) pages as well as performing the actions implied by the input flags. This is part of a patch series aiming to remove the vmas parameter altogether. Suggested-by: Matthew Wilcox (Oracle) Acked-by: Greg Kroah-Hartman Acked-by: David Hildenbrand Reviewed-by: Jason Gunthorpe Acked-by: Christian K=C3=B6nig (for radeon parts) Acked-by: Jarkko Sakkinen Signed-off-by: Lorenzo Stoakes Acked-by: Sean Christopherson (KVM) Reviewed-by: Christoph Hellwig --- arch/x86/kernel/cpu/sgx/ioctl.c | 2 +- drivers/gpu/drm/radeon/radeon_ttm.c | 2 +- drivers/misc/sgi-gru/grufault.c | 2 +- include/linux/mm.h | 3 +-- mm/gup.c | 9 +++------ mm/gup_test.c | 5 ++--- virt/kvm/kvm_main.c | 2 +- 7 files changed, 10 insertions(+), 15 deletions(-) diff --git a/arch/x86/kernel/cpu/sgx/ioctl.c b/arch/x86/kernel/cpu/sgx/ioct= l.c index 21ca0a831b70..5d390df21440 100644 --- a/arch/x86/kernel/cpu/sgx/ioctl.c +++ b/arch/x86/kernel/cpu/sgx/ioctl.c @@ -214,7 +214,7 @@ static int __sgx_encl_add_page(struct sgx_encl *encl, if (!(vma->vm_flags & VM_MAYEXEC)) return -EACCES; =20 - ret =3D get_user_pages(src, 1, 0, &src_page, NULL); + ret =3D get_user_pages(src, 1, 0, &src_page); if (ret < 1) return -EFAULT; =20 diff --git a/drivers/gpu/drm/radeon/radeon_ttm.c b/drivers/gpu/drm/radeon/r= adeon_ttm.c index 2220cdf6a3f6..3a9db030f98f 100644 --- a/drivers/gpu/drm/radeon/radeon_ttm.c +++ b/drivers/gpu/drm/radeon/radeon_ttm.c @@ -359,7 +359,7 @@ static int radeon_ttm_tt_pin_userptr(struct ttm_device = *bdev, struct ttm_tt *ttm struct page **pages =3D ttm->pages + pinned; =20 r =3D get_user_pages(userptr, num_pages, write ? FOLL_WRITE : 0, - pages, NULL); + pages); if (r < 0) goto release_pages; =20 diff --git a/drivers/misc/sgi-gru/grufault.c b/drivers/misc/sgi-gru/grufaul= t.c index b836936e9747..378cf02a2aa1 100644 --- a/drivers/misc/sgi-gru/grufault.c +++ b/drivers/misc/sgi-gru/grufault.c @@ -185,7 +185,7 @@ static int non_atomic_pte_lookup(struct vm_area_struct = *vma, #else *pageshift =3D PAGE_SHIFT; #endif - if (get_user_pages(vaddr, 1, write ? FOLL_WRITE : 0, &page, NULL) <=3D 0) + if (get_user_pages(vaddr, 1, write ? FOLL_WRITE : 0, &page) <=3D 0) return -EFAULT; *paddr =3D page_to_phys(page); put_page(page); diff --git a/include/linux/mm.h b/include/linux/mm.h index db3f66ed2f32..2c1a92bf5626 100644 --- a/include/linux/mm.h +++ b/include/linux/mm.h @@ -2382,8 +2382,7 @@ long pin_user_pages_remote(struct mm_struct *mm, unsigned int gup_flags, struct page **pages, struct vm_area_struct **vmas, int *locked); long get_user_pages(unsigned long start, unsigned long nr_pages, - unsigned int gup_flags, struct page **pages, - struct vm_area_struct **vmas); + unsigned int gup_flags, struct page **pages); long pin_user_pages(unsigned long start, unsigned long nr_pages, unsigned int gup_flags, struct page **pages, struct vm_area_struct **vmas); diff --git a/mm/gup.c b/mm/gup.c index 90d9b65ff35c..b8189396f435 100644 --- a/mm/gup.c +++ b/mm/gup.c @@ -2294,8 +2294,6 @@ long get_user_pages_remote(struct mm_struct *mm, * @pages: array that receives pointers to the pages pinned. * Should be at least nr_pages long. Or NULL, if caller * only intends to ensure the pages are faulted in. - * @vmas: array of pointers to vmas corresponding to each page. - * Or NULL if the caller does not require them. * * This is the same as get_user_pages_remote(), just with a less-flexible * calling convention where we assume that the mm being operated on belong= s to @@ -2303,16 +2301,15 @@ long get_user_pages_remote(struct mm_struct *mm, * obviously don't pass FOLL_REMOTE in here. */ long get_user_pages(unsigned long start, unsigned long nr_pages, - unsigned int gup_flags, struct page **pages, - struct vm_area_struct **vmas) + unsigned int gup_flags, struct page **pages) { int locked =3D 1; =20 - if (!is_valid_gup_args(pages, vmas, NULL, &gup_flags, FOLL_TOUCH)) + if (!is_valid_gup_args(pages, NULL, NULL, &gup_flags, FOLL_TOUCH)) return -EINVAL; =20 return __get_user_pages_locked(current->mm, start, nr_pages, pages, - vmas, &locked, gup_flags); + NULL, &locked, gup_flags); } EXPORT_SYMBOL(get_user_pages); =20 diff --git a/mm/gup_test.c b/mm/gup_test.c index 8ae7307a1bb6..9ba8ea23f84e 100644 --- a/mm/gup_test.c +++ b/mm/gup_test.c @@ -139,8 +139,7 @@ static int __gup_test_ioctl(unsigned int cmd, pages + i); break; case GUP_BASIC_TEST: - nr =3D get_user_pages(addr, nr, gup->gup_flags, pages + i, - NULL); + nr =3D get_user_pages(addr, nr, gup->gup_flags, pages + i); break; case PIN_FAST_BENCHMARK: nr =3D pin_user_pages_fast(addr, nr, gup->gup_flags, @@ -161,7 +160,7 @@ static int __gup_test_ioctl(unsigned int cmd, pages + i, NULL); else nr =3D get_user_pages(addr, nr, gup->gup_flags, - pages + i, NULL); + pages + i); break; default: ret =3D -EINVAL; diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c index cb5c13eee193..eaa5bb8dbadc 100644 --- a/virt/kvm/kvm_main.c +++ b/virt/kvm/kvm_main.c @@ -2477,7 +2477,7 @@ static inline int check_user_page_hwpoison(unsigned l= ong addr) { int rc, flags =3D FOLL_HWPOISON | FOLL_WRITE; =20 - rc =3D get_user_pages(addr, 1, flags, NULL, NULL); + rc =3D get_user_pages(addr, 1, flags, NULL); return rc =3D=3D -EHWPOISON; } =20 --=20 2.40.1 From nobody Wed Feb 11 03:42:06 2026 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 21A59C77B7D for ; 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Sun, 14 May 2023 14:26:51 -0700 (PDT) Received: from lucifer.home ([2a00:23c5:dc8c:8701:1663:9a35:5a7b:1d76]) by smtp.googlemail.com with ESMTPSA id l11-20020a05600c1d0b00b003f1978bbcd6sm25750205wms.3.2023.05.14.14.26.50 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Sun, 14 May 2023 14:26:50 -0700 (PDT) From: Lorenzo Stoakes To: linux-mm@kvack.org, linux-kernel@vger.kernel.org, Andrew Morton , iommu@lists.linux.dev Cc: Matthew Wilcox , David Hildenbrand , kvm@vger.kernel.org, Jason Gunthorpe , Kevin Tian , Joerg Roedel , Will Deacon , Robin Murphy , Alex Williamson , Jens Axboe , Pavel Begunkov , John Hubbard , Lorenzo Stoakes , Jason Gunthorpe Subject: [PATCH v5 2/6] mm/gup: remove unused vmas parameter from pin_user_pages_remote() Date: Sun, 14 May 2023 22:26:47 +0100 Message-Id: <61f0d12058825a14feee6a3292e5a257662e719c.1684097002.git.lstoakes@gmail.com> X-Mailer: git-send-email 2.40.1 In-Reply-To: References: MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Type: text/plain; charset="utf-8" No invocation of pin_user_pages_remote() uses the vmas parameter, so remove it. This forms part of a larger patch set eliminating the use of the vmas parameters altogether. Acked-by: David Hildenbrand Reviewed-by: Jason Gunthorpe Signed-off-by: Lorenzo Stoakes Reviewed-by: Christoph Hellwig --- drivers/iommu/iommufd/pages.c | 4 ++-- drivers/vfio/vfio_iommu_type1.c | 2 +- include/linux/mm.h | 2 +- mm/gup.c | 8 +++----- mm/process_vm_access.c | 2 +- 5 files changed, 8 insertions(+), 10 deletions(-) diff --git a/drivers/iommu/iommufd/pages.c b/drivers/iommu/iommufd/pages.c index 3c47846cc5ef..412ca96be128 100644 --- a/drivers/iommu/iommufd/pages.c +++ b/drivers/iommu/iommufd/pages.c @@ -786,7 +786,7 @@ static int pfn_reader_user_pin(struct pfn_reader_user *= user, user->locked =3D 1; } rc =3D pin_user_pages_remote(pages->source_mm, uptr, npages, - user->gup_flags, user->upages, NULL, + user->gup_flags, user->upages, &user->locked); } if (rc <=3D 0) { @@ -1799,7 +1799,7 @@ static int iopt_pages_rw_page(struct iopt_pages *page= s, unsigned long index, rc =3D pin_user_pages_remote( pages->source_mm, (uintptr_t)(pages->uptr + index * PAGE_SIZE), 1, (flags & IOMMUFD_ACCESS_RW_WRITE) ? FOLL_WRITE : 0, &page, - NULL, NULL); + NULL); mmap_read_unlock(pages->source_mm); if (rc !=3D 1) { if (WARN_ON(rc >=3D 0)) diff --git a/drivers/vfio/vfio_iommu_type1.c b/drivers/vfio/vfio_iommu_type= 1.c index 3d4dd9420c30..3d2d9a944906 100644 --- a/drivers/vfio/vfio_iommu_type1.c +++ b/drivers/vfio/vfio_iommu_type1.c @@ -562,7 +562,7 @@ static int vaddr_get_pfns(struct mm_struct *mm, unsigne= d long vaddr, =20 mmap_read_lock(mm); ret =3D pin_user_pages_remote(mm, vaddr, npages, flags | FOLL_LONGTERM, - pages, NULL, NULL); + pages, NULL); if (ret > 0) { int i; =20 diff --git a/include/linux/mm.h b/include/linux/mm.h index 2c1a92bf5626..8ea82e9e7719 100644 --- a/include/linux/mm.h +++ b/include/linux/mm.h @@ -2380,7 +2380,7 @@ long get_user_pages_remote(struct mm_struct *mm, long pin_user_pages_remote(struct mm_struct *mm, unsigned long start, unsigned long nr_pages, unsigned int gup_flags, struct page **pages, - struct vm_area_struct **vmas, int *locked); + int *locked); long get_user_pages(unsigned long start, unsigned long nr_pages, unsigned int gup_flags, struct page **pages); long pin_user_pages(unsigned long start, unsigned long nr_pages, diff --git a/mm/gup.c b/mm/gup.c index b8189396f435..ce78a5186dbb 100644 --- a/mm/gup.c +++ b/mm/gup.c @@ -3243,8 +3243,6 @@ EXPORT_SYMBOL_GPL(pin_user_pages_fast); * @gup_flags: flags modifying lookup behaviour * @pages: array that receives pointers to the pages pinned. * Should be at least nr_pages long. - * @vmas: array of pointers to vmas corresponding to each page. - * Or NULL if the caller does not require them. * @locked: pointer to lock flag indicating whether lock is held and * subsequently whether VM_FAULT_RETRY functionality can be * utilised. Lock must initially be held. @@ -3259,14 +3257,14 @@ EXPORT_SYMBOL_GPL(pin_user_pages_fast); long pin_user_pages_remote(struct mm_struct *mm, unsigned long start, unsigned long nr_pages, unsigned int gup_flags, struct page **pages, - struct vm_area_struct **vmas, int *locked) + int *locked) { int local_locked =3D 1; =20 - if (!is_valid_gup_args(pages, vmas, locked, &gup_flags, + if (!is_valid_gup_args(pages, NULL, locked, &gup_flags, FOLL_PIN | FOLL_TOUCH | FOLL_REMOTE)) return 0; - return __gup_longterm_locked(mm, start, nr_pages, pages, vmas, + return __gup_longterm_locked(mm, start, nr_pages, pages, NULL, locked ? locked : &local_locked, gup_flags); } diff --git a/mm/process_vm_access.c b/mm/process_vm_access.c index 78dfaf9e8990..0523edab03a6 100644 --- a/mm/process_vm_access.c +++ b/mm/process_vm_access.c @@ -104,7 +104,7 @@ static int process_vm_rw_single_vec(unsigned long addr, mmap_read_lock(mm); pinned_pages =3D pin_user_pages_remote(mm, pa, pinned_pages, flags, process_pages, - NULL, &locked); + &locked); if (locked) mmap_read_unlock(mm); if (pinned_pages <=3D 0) --=20 2.40.1 From nobody Wed Feb 11 03:42:06 2026 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 CC56DC7EE2F for ; Sun, 14 May 2023 21:27:11 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S238023AbjENV1J (ORCPT ); Sun, 14 May 2023 17:27:09 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:45844 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S237835AbjENV1A (ORCPT ); Sun, 14 May 2023 17:27:00 -0400 Received: from mail-wr1-x430.google.com (mail-wr1-x430.google.com [IPv6:2a00:1450:4864:20::430]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 4982AE5A; Sun, 14 May 2023 14:26:57 -0700 (PDT) Received: by mail-wr1-x430.google.com with SMTP id ffacd0b85a97d-307d20548adso2316936f8f.0; Sun, 14 May 2023 14:26:57 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20221208; t=1684099616; x=1686691616; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:from:to:cc:subject:date :message-id:reply-to; bh=4UcwtmbMshSXuvMabtBGpRNNnrw3Ug7R4BdEk+jXhWU=; b=SG8hxf81UnHmvvVjeEeKVeA+UZG3mnFP4B4L90u9UyEYnV56GRHXaKsoFAbnamoQIz 2YZhAbxnr00GHA4RxMN62csLPuERPgX0ifRwc3Q+5e5n1MswXKkZS+0GLgr3wOmfiWgn ZPuChWywNQyL6flbeiqXURGxXz850TfIguYclXkSCjhrPENyODdyxWlKb6Y6tNj6/GX0 Sa4aP/Lpdi2Pnd+QzUgxgJcIiKrwqUjg4swH48d9SIJK5uumdrbd0W4L1hoD19HLBWfG W0/IsO+qeRgPFzYOGC7ClZfu4sQo/MYceDdfxRtZQX+6idplJSEqwKzm4yvlQHNdyKCo IgYg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20221208; t=1684099616; x=1686691616; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:x-gm-message-state:from:to:cc :subject:date:message-id:reply-to; bh=4UcwtmbMshSXuvMabtBGpRNNnrw3Ug7R4BdEk+jXhWU=; b=hveA0hLd9o0a+ctYS6AfvEuWaujCuXaPulm9uoZuE5CLFZtNg72HsQ2XgwG5Gw3A7W NqB5Q0r02jo0HqvNWzXKqXZia+QlFXXh/3IgDIf2Wnp1tD+0Wh5FHViEgLRUppzJYuWe zmgz40RFfHC5yTbYZ1D/oZFSPZjg/iA2tkyzSVtO7y/pRlUwxjSEBj5Geu6BVsyKhhBi 777EqOrN+fq37LVlgccZzctyW7uce59jvSAZkVnEaX1ye8cQz6nBLBjn1+qmvQO2fEI3 zHYcA+X/nLY4OEmgZh57MyTL1wqgaKP0OIMLeZkCsK8EruWOhGkaFByZuIyEWHiXNQp6 8oiQ== X-Gm-Message-State: AC+VfDzbRJN6efBW2xbw9qZlv2T/zCksNeD8nldkBaeDs67R492TkVpP MCzDHEbMukMu09ErehlZ860= X-Google-Smtp-Source: ACHHUZ6hrnBUVpEkIbW4de+Qex2SgXu2P8EgEWvpkktR/SPhZZH9saiI6bvSiuP8lMEwTG863yeNzQ== X-Received: by 2002:a5d:55c2:0:b0:306:5149:3aa8 with SMTP id i2-20020a5d55c2000000b0030651493aa8mr21936695wrw.24.1684099615381; Sun, 14 May 2023 14:26:55 -0700 (PDT) Received: from lucifer.home ([2a00:23c5:dc8c:8701:1663:9a35:5a7b:1d76]) by smtp.googlemail.com with ESMTPSA id d19-20020a1c7313000000b003f508777e33sm2105965wmb.3.2023.05.14.14.26.53 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Sun, 14 May 2023 14:26:54 -0700 (PDT) From: Lorenzo Stoakes To: linux-mm@kvack.org, linux-kernel@vger.kernel.org, Andrew Morton Cc: Matthew Wilcox , David Hildenbrand , linux-arm-kernel@lists.infradead.org, kvm@vger.kernel.org, linux-s390@vger.kernel.org, linux-fsdevel@vger.kernel.org, linux-perf-users@vger.kernel.org, linux-security-module@vger.kernel.org, Catalin Marinas , Will Deacon , Christian Borntraeger , Janosch Frank , Claudio Imbrenda , Heiko Carstens , Vasily Gorbik , Alexander Gordeev , Sven Schnelle , Eric Biederman , Kees Cook , Alexander Viro , Christian Brauner , Peter Zijlstra , Ingo Molnar , Arnaldo Carvalho de Melo , Mark Rutland , Alexander Shishkin , Jiri Olsa , Namhyung Kim , Ian Rogers , Adrian Hunter , Kentaro Takeda , Tetsuo Handa , Paul Moore , James Morris , "Serge E . Hallyn" , Paolo Bonzini , Jens Axboe , Pavel Begunkov , Jason Gunthorpe , John Hubbard , Lorenzo Stoakes Subject: [PATCH v5 3/6] mm/gup: remove vmas parameter from get_user_pages_remote() Date: Sun, 14 May 2023 22:26:51 +0100 Message-Id: X-Mailer: git-send-email 2.40.1 In-Reply-To: References: MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Type: text/plain; charset="utf-8" The only instances of get_user_pages_remote() invocations which used the vmas parameter were for a single page which can instead simply look up the VMA directly. In particular:- - __update_ref_ctr() looked up the VMA but did nothing with it so we simply remove it. - __access_remote_vm() was already using vma_lookup() when the original lookup failed so by doing the lookup directly this also de-duplicates the code. We are able to perform these VMA operations as we already hold the mmap_lock in order to be able to call get_user_pages_remote(). As part of this work we add get_user_page_vma_remote() which abstracts the VMA lookup, error handling and decrementing the page reference count should the VMA lookup fail. This forms part of a broader set of patches intended to eliminate the vmas parameter altogether. Reviewed-by: Catalin Marinas (for arm64) Acked-by: David Hildenbrand Reviewed-by: Janosch Frank (for s390) Signed-off-by: Lorenzo Stoakes Reviewed-by: Christoph Hellwig --- arch/arm64/kernel/mte.c | 17 +++++++++-------- arch/s390/kvm/interrupt.c | 2 +- fs/exec.c | 2 +- include/linux/mm.h | 34 +++++++++++++++++++++++++++++++--- kernel/events/uprobes.c | 13 +++++-------- mm/gup.c | 12 ++++-------- mm/memory.c | 14 +++++++------- mm/rmap.c | 2 +- security/tomoyo/domain.c | 2 +- virt/kvm/async_pf.c | 3 +-- 10 files changed, 61 insertions(+), 40 deletions(-) diff --git a/arch/arm64/kernel/mte.c b/arch/arm64/kernel/mte.c index f5bcb0dc6267..cc793c246653 100644 --- a/arch/arm64/kernel/mte.c +++ b/arch/arm64/kernel/mte.c @@ -419,10 +419,9 @@ long get_mte_ctrl(struct task_struct *task) static int __access_remote_tags(struct mm_struct *mm, unsigned long addr, struct iovec *kiov, unsigned int gup_flags) { - struct vm_area_struct *vma; void __user *buf =3D kiov->iov_base; size_t len =3D kiov->iov_len; - int ret; + int err =3D 0; int write =3D gup_flags & FOLL_WRITE; =20 if (!access_ok(buf, len)) @@ -432,14 +431,16 @@ static int __access_remote_tags(struct mm_struct *mm,= unsigned long addr, return -EIO; =20 while (len) { + struct vm_area_struct *vma; unsigned long tags, offset; void *maddr; - struct page *page =3D NULL; + struct page *page =3D get_user_page_vma_remote(mm, addr, + gup_flags, &vma); =20 - ret =3D get_user_pages_remote(mm, addr, 1, gup_flags, &page, - &vma, NULL); - if (ret <=3D 0) + if (IS_ERR_OR_NULL(page)) { + err =3D page =3D=3D NULL ? -EIO : PTR_ERR(page); break; + } =20 /* * Only copy tags if the page has been mapped as PROT_MTE @@ -449,7 +450,7 @@ static int __access_remote_tags(struct mm_struct *mm, u= nsigned long addr, * was never mapped with PROT_MTE. */ if (!(vma->vm_flags & VM_MTE)) { - ret =3D -EOPNOTSUPP; + err =3D -EOPNOTSUPP; put_page(page); break; } @@ -482,7 +483,7 @@ static int __access_remote_tags(struct mm_struct *mm, u= nsigned long addr, kiov->iov_len =3D buf - kiov->iov_base; if (!kiov->iov_len) { /* check for error accessing the tracee's address space */ - if (ret <=3D 0) + if (err) return -EIO; else return -EFAULT; diff --git a/arch/s390/kvm/interrupt.c b/arch/s390/kvm/interrupt.c index da6dac36e959..9bd0a873f3b1 100644 --- a/arch/s390/kvm/interrupt.c +++ b/arch/s390/kvm/interrupt.c @@ -2777,7 +2777,7 @@ static struct page *get_map_page(struct kvm *kvm, u64= uaddr) =20 mmap_read_lock(kvm->mm); get_user_pages_remote(kvm->mm, uaddr, 1, FOLL_WRITE, - &page, NULL, NULL); + &page, NULL); mmap_read_unlock(kvm->mm); return page; } diff --git a/fs/exec.c b/fs/exec.c index a466e797c8e2..25c65b64544b 100644 --- a/fs/exec.c +++ b/fs/exec.c @@ -220,7 +220,7 @@ static struct page *get_arg_page(struct linux_binprm *b= prm, unsigned long pos, */ mmap_read_lock(bprm->mm); ret =3D get_user_pages_remote(bprm->mm, pos, 1, gup_flags, - &page, NULL, NULL); + &page, NULL); mmap_read_unlock(bprm->mm); if (ret <=3D 0) return NULL; diff --git a/include/linux/mm.h b/include/linux/mm.h index 8ea82e9e7719..679b41ef7a6d 100644 --- a/include/linux/mm.h +++ b/include/linux/mm.h @@ -2366,6 +2366,9 @@ static inline void unmap_shared_mapping_range(struct = address_space *mapping, unmap_mapping_range(mapping, holebegin, holelen, 0); } =20 +static inline struct vm_area_struct *vma_lookup(struct mm_struct *mm, + unsigned long addr); + extern int access_process_vm(struct task_struct *tsk, unsigned long addr, void *buf, int len, unsigned int gup_flags); extern int access_remote_vm(struct mm_struct *mm, unsigned long addr, @@ -2374,13 +2377,38 @@ extern int __access_remote_vm(struct mm_struct *mm,= unsigned long addr, void *buf, int len, unsigned int gup_flags); =20 long get_user_pages_remote(struct mm_struct *mm, - unsigned long start, unsigned long nr_pages, - unsigned int gup_flags, struct page **pages, - struct vm_area_struct **vmas, int *locked); + unsigned long start, unsigned long nr_pages, + unsigned int gup_flags, struct page **pages, + int *locked); long pin_user_pages_remote(struct mm_struct *mm, unsigned long start, unsigned long nr_pages, unsigned int gup_flags, struct page **pages, int *locked); + +static inline struct page *get_user_page_vma_remote(struct mm_struct *mm, + unsigned long addr, + int gup_flags, + struct vm_area_struct **vmap) +{ + struct page *page; + struct vm_area_struct *vma; + int got =3D get_user_pages_remote(mm, addr, 1, gup_flags, &page, NULL); + + if (got < 0) + return ERR_PTR(got); + if (got =3D=3D 0) + return NULL; + + vma =3D vma_lookup(mm, addr); + if (WARN_ON_ONCE(!vma)) { + put_page(page); + return ERR_PTR(-EINVAL); + } + + *vmap =3D vma; + return page; +} + long get_user_pages(unsigned long start, unsigned long nr_pages, unsigned int gup_flags, struct page **pages); long pin_user_pages(unsigned long start, unsigned long nr_pages, diff --git a/kernel/events/uprobes.c b/kernel/events/uprobes.c index 59887c69d54c..cac3aef7c6f7 100644 --- a/kernel/events/uprobes.c +++ b/kernel/events/uprobes.c @@ -365,7 +365,6 @@ __update_ref_ctr(struct mm_struct *mm, unsigned long va= ddr, short d) { void *kaddr; struct page *page; - struct vm_area_struct *vma; int ret; short *ptr; =20 @@ -373,7 +372,7 @@ __update_ref_ctr(struct mm_struct *mm, unsigned long va= ddr, short d) return -EINVAL; =20 ret =3D get_user_pages_remote(mm, vaddr, 1, - FOLL_WRITE, &page, &vma, NULL); + FOLL_WRITE, &page, NULL); if (unlikely(ret <=3D 0)) { /* * We are asking for 1 page. If get_user_pages_remote() fails, @@ -474,10 +473,9 @@ int uprobe_write_opcode(struct arch_uprobe *auprobe, s= truct mm_struct *mm, if (is_register) gup_flags |=3D FOLL_SPLIT_PMD; /* Read the page with vaddr into memory */ - ret =3D get_user_pages_remote(mm, vaddr, 1, gup_flags, - &old_page, &vma, NULL); - if (ret <=3D 0) - return ret; + old_page =3D get_user_page_vma_remote(mm, vaddr, gup_flags, &vma); + if (IS_ERR_OR_NULL(old_page)) + return PTR_ERR(old_page); =20 ret =3D verify_opcode(old_page, vaddr, &opcode); if (ret <=3D 0) @@ -2027,8 +2025,7 @@ static int is_trap_at_addr(struct mm_struct *mm, unsi= gned long vaddr) * but we treat this as a 'remote' access since it is * essentially a kernel access to the memory. */ - result =3D get_user_pages_remote(mm, vaddr, 1, FOLL_FORCE, &page, - NULL, NULL); + result =3D get_user_pages_remote(mm, vaddr, 1, FOLL_FORCE, &page, NULL); if (result < 0) return result; =20 diff --git a/mm/gup.c b/mm/gup.c index ce78a5186dbb..1493cc8dd526 100644 --- a/mm/gup.c +++ b/mm/gup.c @@ -2208,8 +2208,6 @@ static bool is_valid_gup_args(struct page **pages, st= ruct vm_area_struct **vmas, * @pages: array that receives pointers to the pages pinned. * Should be at least nr_pages long. Or NULL, if caller * only intends to ensure the pages are faulted in. - * @vmas: array of pointers to vmas corresponding to each page. - * Or NULL if the caller does not require them. * @locked: pointer to lock flag indicating whether lock is held and * subsequently whether VM_FAULT_RETRY functionality can be * utilised. Lock must initially be held. @@ -2224,8 +2222,6 @@ static bool is_valid_gup_args(struct page **pages, st= ruct vm_area_struct **vmas, * * The caller is responsible for releasing returned @pages, via put_page(). * - * @vmas are valid only as long as mmap_lock is held. - * * Must be called with mmap_lock held for read or write. * * get_user_pages_remote walks a process's page tables and takes a referen= ce @@ -2262,15 +2258,15 @@ static bool is_valid_gup_args(struct page **pages, = struct vm_area_struct **vmas, long get_user_pages_remote(struct mm_struct *mm, unsigned long start, unsigned long nr_pages, unsigned int gup_flags, struct page **pages, - struct vm_area_struct **vmas, int *locked) + int *locked) { int local_locked =3D 1; =20 - if (!is_valid_gup_args(pages, vmas, locked, &gup_flags, + if (!is_valid_gup_args(pages, NULL, locked, &gup_flags, FOLL_TOUCH | FOLL_REMOTE)) return -EINVAL; =20 - return __get_user_pages_locked(mm, start, nr_pages, pages, vmas, + return __get_user_pages_locked(mm, start, nr_pages, pages, NULL, locked ? locked : &local_locked, gup_flags); } @@ -2280,7 +2276,7 @@ EXPORT_SYMBOL(get_user_pages_remote); long get_user_pages_remote(struct mm_struct *mm, unsigned long start, unsigned long nr_pages, unsigned int gup_flags, struct page **pages, - struct vm_area_struct **vmas, int *locked) + int *locked) { return 0; } diff --git a/mm/memory.c b/mm/memory.c index 146bb94764f8..63632a5eafc1 100644 --- a/mm/memory.c +++ b/mm/memory.c @@ -5590,7 +5590,6 @@ EXPORT_SYMBOL_GPL(generic_access_phys); int __access_remote_vm(struct mm_struct *mm, unsigned long addr, void *buf, int len, unsigned int gup_flags) { - struct vm_area_struct *vma; void *old_buf =3D buf; int write =3D gup_flags & FOLL_WRITE; =20 @@ -5599,13 +5598,15 @@ int __access_remote_vm(struct mm_struct *mm, unsign= ed long addr, void *buf, =20 /* ignore errors, just check how much was successfully transferred */ while (len) { - int bytes, ret, offset; + int bytes, offset; void *maddr; - struct page *page =3D NULL; + struct vm_area_struct *vma; + struct page *page =3D get_user_page_vma_remote(mm, addr, + gup_flags, &vma); + + if (IS_ERR_OR_NULL(page)) { + int ret =3D 0; =20 - ret =3D get_user_pages_remote(mm, addr, 1, - gup_flags, &page, &vma, NULL); - if (ret <=3D 0) { #ifndef CONFIG_HAVE_IOREMAP_PROT break; #else @@ -5613,7 +5614,6 @@ int __access_remote_vm(struct mm_struct *mm, unsigned= long addr, void *buf, * Check if this is a VM_IO | VM_PFNMAP VMA, which * we can access using slightly different code. */ - vma =3D vma_lookup(mm, addr); if (!vma) break; if (vma->vm_ops && vma->vm_ops->access) diff --git a/mm/rmap.c b/mm/rmap.c index b42fc0389c24..ae127f60a4fb 100644 --- a/mm/rmap.c +++ b/mm/rmap.c @@ -2328,7 +2328,7 @@ int make_device_exclusive_range(struct mm_struct *mm,= unsigned long start, =20 npages =3D get_user_pages_remote(mm, start, npages, FOLL_GET | FOLL_WRITE | FOLL_SPLIT_PMD, - pages, NULL, NULL); + pages, NULL); if (npages < 0) return npages; =20 diff --git a/security/tomoyo/domain.c b/security/tomoyo/domain.c index 31af29f669d2..ac20c0bdff9d 100644 --- a/security/tomoyo/domain.c +++ b/security/tomoyo/domain.c @@ -916,7 +916,7 @@ bool tomoyo_dump_page(struct linux_binprm *bprm, unsign= ed long pos, */ mmap_read_lock(bprm->mm); ret =3D get_user_pages_remote(bprm->mm, pos, 1, - FOLL_FORCE, &page, NULL, NULL); + FOLL_FORCE, &page, NULL); mmap_read_unlock(bprm->mm); if (ret <=3D 0) return false; diff --git a/virt/kvm/async_pf.c b/virt/kvm/async_pf.c index 9bfe1d6f6529..e033c79d528e 100644 --- a/virt/kvm/async_pf.c +++ b/virt/kvm/async_pf.c @@ -61,8 +61,7 @@ static void async_pf_execute(struct work_struct *work) * access remotely. */ mmap_read_lock(mm); - get_user_pages_remote(mm, addr, 1, FOLL_WRITE, NULL, NULL, - &locked); + get_user_pages_remote(mm, addr, 1, FOLL_WRITE, NULL, &locked); if (locked) mmap_read_unlock(mm); =20 --=20 2.40.1 From nobody Wed Feb 11 03:42:06 2026 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 582F9C77B7D for ; Sun, 14 May 2023 21:27:18 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S237976AbjENV1O (ORCPT ); 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Sun, 14 May 2023 14:26:57 -0700 (PDT) From: Lorenzo Stoakes To: linux-mm@kvack.org, linux-kernel@vger.kernel.org, Andrew Morton Cc: Matthew Wilcox , David Hildenbrand , Jens Axboe , Pavel Begunkov , io-uring@vger.kernel.org, Jason Gunthorpe , John Hubbard , Lorenzo Stoakes Subject: [PATCH v5 4/6] io_uring: rsrc: delegate VMA file-backed check to GUP Date: Sun, 14 May 2023 22:26:55 +0100 Message-Id: <642128d50f5423b3331e3108f8faf6b8ac0d957e.1684097002.git.lstoakes@gmail.com> X-Mailer: git-send-email 2.40.1 In-Reply-To: References: MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Type: text/plain; charset="utf-8" Now that the GUP explicitly checks FOLL_LONGTERM pin_user_pages() for broken file-backed mappings in "mm/gup: disallow FOLL_LONGTERM GUP-nonfast writing to file-backed mappings", there is no need to explicitly check VMAs for this condition, so simply remove this logic from io_uring altogether. Signed-off-by: Lorenzo Stoakes Reviewed-by: Christoph Hellwig Reviewed-by: David Hildenbrand Reviewed-by: Jens Axboe --- io_uring/rsrc.c | 34 ++++++---------------------------- 1 file changed, 6 insertions(+), 28 deletions(-) diff --git a/io_uring/rsrc.c b/io_uring/rsrc.c index d46f72a5ef73..b6451f8bc5d5 100644 --- a/io_uring/rsrc.c +++ b/io_uring/rsrc.c @@ -1030,9 +1030,8 @@ static int io_buffer_account_pin(struct io_ring_ctx *= ctx, struct page **pages, struct page **io_pin_pages(unsigned long ubuf, unsigned long len, int *npa= ges) { unsigned long start, end, nr_pages; - struct vm_area_struct **vmas =3D NULL; struct page **pages =3D NULL; - int i, pret, ret =3D -ENOMEM; + int pret, ret =3D -ENOMEM; =20 end =3D (ubuf + len + PAGE_SIZE - 1) >> PAGE_SHIFT; start =3D ubuf >> PAGE_SHIFT; @@ -1042,45 +1041,24 @@ struct page **io_pin_pages(unsigned long ubuf, unsi= gned long len, int *npages) if (!pages) goto done; =20 - vmas =3D kvmalloc_array(nr_pages, sizeof(struct vm_area_struct *), - GFP_KERNEL); - if (!vmas) - goto done; - ret =3D 0; mmap_read_lock(current->mm); pret =3D pin_user_pages(ubuf, nr_pages, FOLL_WRITE | FOLL_LONGTERM, - pages, vmas); - if (pret =3D=3D nr_pages) { - /* don't support file backed memory */ - for (i =3D 0; i < nr_pages; i++) { - struct vm_area_struct *vma =3D vmas[i]; - - if (vma_is_shmem(vma)) - continue; - if (vma->vm_file && - !is_file_hugepages(vma->vm_file)) { - ret =3D -EOPNOTSUPP; - break; - } - } + pages, NULL); + if (pret =3D=3D nr_pages) *npages =3D nr_pages; - } else { + else ret =3D pret < 0 ? pret : -EFAULT; - } + mmap_read_unlock(current->mm); if (ret) { - /* - * if we did partial map, or found file backed vmas, - * release any pages we did get - */ + /* if we did partial map, release any pages we did get */ if (pret > 0) unpin_user_pages(pages, pret); goto done; } ret =3D 0; done: - kvfree(vmas); if (ret < 0) { kvfree(pages); pages =3D ERR_PTR(ret); --=20 2.40.1 From nobody Wed Feb 11 03:42:06 2026 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 A1495C7EE2A for ; Sun, 14 May 2023 21:27:35 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S238032AbjENV1d (ORCPT ); Sun, 14 May 2023 17:27:33 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:46352 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S237948AbjENV1M (ORCPT ); Sun, 14 May 2023 17:27:12 -0400 Received: from mail-wr1-x429.google.com (mail-wr1-x429.google.com [IPv6:2a00:1450:4864:20::429]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id B4D9A19AD; Sun, 14 May 2023 14:27:03 -0700 (PDT) Received: by mail-wr1-x429.google.com with SMTP id ffacd0b85a97d-3078fa679a7so8523692f8f.3; Sun, 14 May 2023 14:27:03 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20221208; t=1684099621; x=1686691621; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:from:to:cc:subject:date :message-id:reply-to; bh=8xqzyCEy7iofGcOYzYypeQYEUsssg0r/A+Ok0DOjdDs=; b=aoQGznX+L0dqapBQrZ7tkkNVdcbVvdSJlnUDKwjlWhMHJsKAuaUDUnJC42eQD2DeDX 34fO8/v7vg1LUopNvlyFJXzAO8PJUfjM3OQDqGW4BrssZLPdgbji8y3zkxIzTeu5JVw+ FV+CRnz59VmbrLGfyt4pGVm2hqrgAeBWO/vmr91k4swlQ7b3D85FRtZxbGcfBOxjKMkn d6RdWLeX4B78nbG17RhE7r0ymv0s8n0GnnM29Du5pRxfNwNAvV4LSbovqFC2br4iXOY0 F6V6C6RK12INseuaPzDfQvZ3a4AIEsBo87ya77kVsQ2VR2mFMjFu/AjnVpJftddk4v0z Z6og== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20221208; t=1684099621; x=1686691621; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:x-gm-message-state:from:to:cc :subject:date:message-id:reply-to; bh=8xqzyCEy7iofGcOYzYypeQYEUsssg0r/A+Ok0DOjdDs=; b=lFPxqYFhqRmXmHyxFo1K79Im/VS+q/fEoZ5QLhBd8ubvmulMcRRY3TROkfuP36RUbG +xr6uO8zZyWa3wftZGc7b7qkFeh/hz6jQrnf5NbtDeNEdCQXWIE6ulFOT79a3dce+nJo LsHXiUElyvuGkjkKicUIYG1z4Gwu8ITuttliRA0GU51a2B3wwizQqdKKK5I9VMs2bAhY qsfopKL6Yp1fu27bg+kzWiAlIEpR8lTxLMlTSyoW26bbAGlYUoUnzac8yu7sTYs2CghT /TvCPBtgLfLq3LahxojvzxcBE+8LSssNXH9D1ICHCp5Pn/MlrHV9AiNuK6cE4EZHEl4x dX5Q== X-Gm-Message-State: AC+VfDwwGJrQ+ICIo7LvTd8n1kKFZL3AKANYJMQZoOuWEjGtmwPmZA/e HDyTUMBMhgqFctQB/3Z2IrY= X-Google-Smtp-Source: ACHHUZ6PRLUWV/JXBbb+jR9+33X81exRRn6i14eei9wAVcEb3WES66stfPnuGtQX6n6Zzc9+QFQNkQ== X-Received: by 2002:adf:ec45:0:b0:306:3f97:4847 with SMTP id w5-20020adfec45000000b003063f974847mr21210684wrn.65.1684099621384; Sun, 14 May 2023 14:27:01 -0700 (PDT) Received: from lucifer.home ([2a00:23c5:dc8c:8701:1663:9a35:5a7b:1d76]) by smtp.googlemail.com with ESMTPSA id d18-20020adfe852000000b002fe13ec49fasm30174117wrn.98.2023.05.14.14.26.59 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Sun, 14 May 2023 14:27:00 -0700 (PDT) From: Lorenzo Stoakes To: linux-mm@kvack.org, linux-kernel@vger.kernel.org, Andrew Morton Cc: Matthew Wilcox , David Hildenbrand , Michael Ellerman , Nicholas Piggin , Christophe Leroy , Dennis Dalessandro , Jason Gunthorpe , Leon Romanovsky , Christian Benvenuti , Nelson Escobar , Bernard Metzler , Mauro Carvalho Chehab , "Michael S . Tsirkin" , Jason Wang , Jens Axboe , Pavel Begunkov , Bjorn Topel , Magnus Karlsson , Maciej Fijalkowski , Jonathan Lemon , "David S . Miller" , Eric Dumazet , Jakub Kicinski , Paolo Abeni , Alexei Starovoitov , Daniel Borkmann , Jesper Dangaard Brouer , John Fastabend , linuxppc-dev@lists.ozlabs.org, linux-rdma@vger.kernel.org, linux-media@vger.kernel.org, virtualization@lists.linux-foundation.org, kvm@vger.kernel.org, netdev@vger.kernel.org, io-uring@vger.kernel.org, bpf@vger.kernel.org, John Hubbard , Lorenzo Stoakes Subject: [PATCH v5 5/6] mm/gup: remove vmas parameter from pin_user_pages() Date: Sun, 14 May 2023 22:26:58 +0100 Message-Id: X-Mailer: git-send-email 2.40.1 In-Reply-To: References: MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Type: text/plain; charset="utf-8" We are now in a position where no caller of pin_user_pages() requires the vmas parameter at all, so eliminate this parameter from the function and all callers. This clears the way to removing the vmas parameter from GUP altogether. Acked-by: David Hildenbrand Acked-by: Dennis Dalessandro (for= qib) Signed-off-by: Lorenzo Stoakes Acked-by: Sakari Ailus # drivers/media Reviewed-by: Christoph Hellwig --- arch/powerpc/mm/book3s64/iommu_api.c | 2 +- drivers/infiniband/hw/qib/qib_user_pages.c | 2 +- drivers/infiniband/hw/usnic/usnic_uiom.c | 2 +- drivers/infiniband/sw/siw/siw_mem.c | 2 +- drivers/media/v4l2-core/videobuf-dma-sg.c | 2 +- drivers/vdpa/vdpa_user/vduse_dev.c | 2 +- drivers/vhost/vdpa.c | 2 +- include/linux/mm.h | 3 +-- io_uring/rsrc.c | 2 +- mm/gup.c | 9 +++------ mm/gup_test.c | 9 ++++----- net/xdp/xdp_umem.c | 2 +- 12 files changed, 17 insertions(+), 22 deletions(-) diff --git a/arch/powerpc/mm/book3s64/iommu_api.c b/arch/powerpc/mm/book3s6= 4/iommu_api.c index 81d7185e2ae8..d19fb1f3007d 100644 --- a/arch/powerpc/mm/book3s64/iommu_api.c +++ b/arch/powerpc/mm/book3s64/iommu_api.c @@ -105,7 +105,7 @@ static long mm_iommu_do_alloc(struct mm_struct *mm, uns= igned long ua, =20 ret =3D pin_user_pages(ua + (entry << PAGE_SHIFT), n, FOLL_WRITE | FOLL_LONGTERM, - mem->hpages + entry, NULL); + mem->hpages + entry); if (ret =3D=3D n) { pinned +=3D n; continue; diff --git a/drivers/infiniband/hw/qib/qib_user_pages.c b/drivers/infiniban= d/hw/qib/qib_user_pages.c index f693bc753b6b..1bb7507325bc 100644 --- a/drivers/infiniband/hw/qib/qib_user_pages.c +++ b/drivers/infiniband/hw/qib/qib_user_pages.c @@ -111,7 +111,7 @@ int qib_get_user_pages(unsigned long start_page, size_t= num_pages, ret =3D pin_user_pages(start_page + got * PAGE_SIZE, num_pages - got, FOLL_LONGTERM | FOLL_WRITE, - p + got, NULL); + p + got); if (ret < 0) { mmap_read_unlock(current->mm); goto bail_release; diff --git a/drivers/infiniband/hw/usnic/usnic_uiom.c b/drivers/infiniband/= hw/usnic/usnic_uiom.c index 2a5cac2658ec..84e0f41e7dfa 100644 --- a/drivers/infiniband/hw/usnic/usnic_uiom.c +++ b/drivers/infiniband/hw/usnic/usnic_uiom.c @@ -140,7 +140,7 @@ static int usnic_uiom_get_pages(unsigned long addr, siz= e_t size, int writable, ret =3D pin_user_pages(cur_base, min_t(unsigned long, npages, PAGE_SIZE / sizeof(struct page *)), - gup_flags, page_list, NULL); + gup_flags, page_list); =20 if (ret < 0) goto out; diff --git a/drivers/infiniband/sw/siw/siw_mem.c b/drivers/infiniband/sw/si= w/siw_mem.c index f51ab2ccf151..e6e25f15567d 100644 --- a/drivers/infiniband/sw/siw/siw_mem.c +++ b/drivers/infiniband/sw/siw/siw_mem.c @@ -422,7 +422,7 @@ struct siw_umem *siw_umem_get(u64 start, u64 len, bool = writable) umem->page_chunk[i].plist =3D plist; while (nents) { rv =3D pin_user_pages(first_page_va, nents, foll_flags, - plist, NULL); + plist); if (rv < 0) goto out_sem_up; =20 diff --git a/drivers/media/v4l2-core/videobuf-dma-sg.c b/drivers/media/v4l2= -core/videobuf-dma-sg.c index 53001532e8e3..405b89ea1054 100644 --- a/drivers/media/v4l2-core/videobuf-dma-sg.c +++ b/drivers/media/v4l2-core/videobuf-dma-sg.c @@ -180,7 +180,7 @@ static int videobuf_dma_init_user_locked(struct videobu= f_dmabuf *dma, data, size, dma->nr_pages); =20 err =3D pin_user_pages(data & PAGE_MASK, dma->nr_pages, gup_flags, - dma->pages, NULL); + dma->pages); =20 if (err !=3D dma->nr_pages) { dma->nr_pages =3D (err >=3D 0) ? err : 0; diff --git a/drivers/vdpa/vdpa_user/vduse_dev.c b/drivers/vdpa/vdpa_user/vd= use_dev.c index de97e38c3b82..4d4405f058e8 100644 --- a/drivers/vdpa/vdpa_user/vduse_dev.c +++ b/drivers/vdpa/vdpa_user/vduse_dev.c @@ -1052,7 +1052,7 @@ static int vduse_dev_reg_umem(struct vduse_dev *dev, goto out; =20 pinned =3D pin_user_pages(uaddr, npages, FOLL_LONGTERM | FOLL_WRITE, - page_list, NULL); + page_list); if (pinned !=3D npages) { ret =3D pinned < 0 ? pinned : -ENOMEM; goto out; diff --git a/drivers/vhost/vdpa.c b/drivers/vhost/vdpa.c index 8c1aefc865f0..61223fcbe82b 100644 --- a/drivers/vhost/vdpa.c +++ b/drivers/vhost/vdpa.c @@ -983,7 +983,7 @@ static int vhost_vdpa_pa_map(struct vhost_vdpa *v, while (npages) { sz2pin =3D min_t(unsigned long, npages, list_size); pinned =3D pin_user_pages(cur_base, sz2pin, - gup_flags, page_list, NULL); + gup_flags, page_list); if (sz2pin !=3D pinned) { if (pinned < 0) { ret =3D pinned; diff --git a/include/linux/mm.h b/include/linux/mm.h index 679b41ef7a6d..db09c7062965 100644 --- a/include/linux/mm.h +++ b/include/linux/mm.h @@ -2412,8 +2412,7 @@ static inline struct page *get_user_page_vma_remote(s= truct mm_struct *mm, long get_user_pages(unsigned long start, unsigned long nr_pages, unsigned int gup_flags, struct page **pages); long pin_user_pages(unsigned long start, unsigned long nr_pages, - unsigned int gup_flags, struct page **pages, - struct vm_area_struct **vmas); + unsigned int gup_flags, struct page **pages); long get_user_pages_unlocked(unsigned long start, unsigned long nr_pages, struct page **pages, unsigned int gup_flags); long pin_user_pages_unlocked(unsigned long start, unsigned long nr_pages, diff --git a/io_uring/rsrc.c b/io_uring/rsrc.c index b6451f8bc5d5..b56bda46a9eb 100644 --- a/io_uring/rsrc.c +++ b/io_uring/rsrc.c @@ -1044,7 +1044,7 @@ struct page **io_pin_pages(unsigned long ubuf, unsign= ed long len, int *npages) ret =3D 0; mmap_read_lock(current->mm); pret =3D pin_user_pages(ubuf, nr_pages, FOLL_WRITE | FOLL_LONGTERM, - pages, NULL); + pages); if (pret =3D=3D nr_pages) *npages =3D nr_pages; else diff --git a/mm/gup.c b/mm/gup.c index 1493cc8dd526..36701b5f0123 100644 --- a/mm/gup.c +++ b/mm/gup.c @@ -3274,8 +3274,6 @@ EXPORT_SYMBOL(pin_user_pages_remote); * @gup_flags: flags modifying lookup behaviour * @pages: array that receives pointers to the pages pinned. * Should be at least nr_pages long. - * @vmas: array of pointers to vmas corresponding to each page. - * Or NULL if the caller does not require them. * * Nearly the same as get_user_pages(), except that FOLL_TOUCH is not set,= and * FOLL_PIN is set. @@ -3284,15 +3282,14 @@ EXPORT_SYMBOL(pin_user_pages_remote); * see Documentation/core-api/pin_user_pages.rst for details. */ long pin_user_pages(unsigned long start, unsigned long nr_pages, - unsigned int gup_flags, struct page **pages, - struct vm_area_struct **vmas) + unsigned int gup_flags, struct page **pages) { int locked =3D 1; =20 - if (!is_valid_gup_args(pages, vmas, NULL, &gup_flags, FOLL_PIN)) + if (!is_valid_gup_args(pages, NULL, NULL, &gup_flags, FOLL_PIN)) return 0; return __gup_longterm_locked(current->mm, start, nr_pages, - pages, vmas, &locked, gup_flags); + pages, NULL, &locked, gup_flags); } EXPORT_SYMBOL(pin_user_pages); =20 diff --git a/mm/gup_test.c b/mm/gup_test.c index 9ba8ea23f84e..1668ce0e0783 100644 --- a/mm/gup_test.c +++ b/mm/gup_test.c @@ -146,18 +146,17 @@ static int __gup_test_ioctl(unsigned int cmd, pages + i); break; case PIN_BASIC_TEST: - nr =3D pin_user_pages(addr, nr, gup->gup_flags, pages + i, - NULL); + nr =3D pin_user_pages(addr, nr, gup->gup_flags, pages + i); break; case PIN_LONGTERM_BENCHMARK: nr =3D pin_user_pages(addr, nr, gup->gup_flags | FOLL_LONGTERM, - pages + i, NULL); + pages + i); break; case DUMP_USER_PAGES_TEST: if (gup->test_flags & GUP_TEST_FLAG_DUMP_PAGES_USE_PIN) nr =3D pin_user_pages(addr, nr, gup->gup_flags, - pages + i, NULL); + pages + i); else nr =3D get_user_pages(addr, nr, gup->gup_flags, pages + i); @@ -270,7 +269,7 @@ static inline int pin_longterm_test_start(unsigned long= arg) gup_flags, pages); else cur_pages =3D pin_user_pages(addr, remaining_pages, - gup_flags, pages, NULL); + gup_flags, pages); if (cur_pages < 0) { pin_longterm_test_stop(); ret =3D cur_pages; diff --git a/net/xdp/xdp_umem.c b/net/xdp/xdp_umem.c index 02207e852d79..06cead2b8e34 100644 --- a/net/xdp/xdp_umem.c +++ b/net/xdp/xdp_umem.c @@ -103,7 +103,7 @@ static int xdp_umem_pin_pages(struct xdp_umem *umem, un= signed long address) =20 mmap_read_lock(current->mm); npgs =3D pin_user_pages(address, umem->npgs, - gup_flags | FOLL_LONGTERM, &umem->pgs[0], NULL); + gup_flags | FOLL_LONGTERM, &umem->pgs[0]); mmap_read_unlock(current->mm); =20 if (npgs !=3D umem->npgs) { --=20 2.40.1 From nobody Wed Feb 11 03:42:06 2026 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 9E3C2C77B7D for ; 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Sun, 14 May 2023 14:27:04 -0700 (PDT) Received: from lucifer.home ([2a00:23c5:dc8c:8701:1663:9a35:5a7b:1d76]) by smtp.googlemail.com with ESMTPSA id r13-20020adfe68d000000b003012030a0c6sm30126843wrm.18.2023.05.14.14.27.02 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Sun, 14 May 2023 14:27:03 -0700 (PDT) From: Lorenzo Stoakes To: linux-mm@kvack.org, linux-kernel@vger.kernel.org, Andrew Morton Cc: Matthew Wilcox , David Hildenbrand , Mike Kravetz , Muchun Song , Jens Axboe , Pavel Begunkov , Jason Gunthorpe , John Hubbard , Lorenzo Stoakes Subject: [PATCH v5 6/6] mm/gup: remove vmas array from internal GUP functions Date: Sun, 14 May 2023 22:27:01 +0100 Message-Id: <23f5b6e75ccf31565355cd37bf1253d20f2e6388.1684097002.git.lstoakes@gmail.com> X-Mailer: git-send-email 2.40.1 In-Reply-To: References: MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Type: text/plain; charset="utf-8" Now we have eliminated all callers to GUP APIs which use the vmas parameter, eliminate it altogether. This eliminates a class of bugs where vmas might have been kept around longer than the mmap_lock and thus we need not be concerned about locks being dropped during this operation leaving behind dangling pointers. This simplifies the GUP API and makes it considerably clearer as to its purpose - follow flags are applied and if pinning, an array of pages is returned. Acked-by: David Hildenbrand Signed-off-by: Lorenzo Stoakes Reviewed-by: Christoph Hellwig --- include/linux/hugetlb.h | 10 ++--- mm/gup.c | 83 +++++++++++++++-------------------------- mm/hugetlb.c | 24 +++++------- 3 files changed, 45 insertions(+), 72 deletions(-) diff --git a/include/linux/hugetlb.h b/include/linux/hugetlb.h index 6d041aa9f0fe..b2b698f9a2ec 100644 --- a/include/linux/hugetlb.h +++ b/include/linux/hugetlb.h @@ -133,9 +133,8 @@ int copy_hugetlb_page_range(struct mm_struct *, struct = mm_struct *, struct page *hugetlb_follow_page_mask(struct vm_area_struct *vma, unsigned long address, unsigned int flags); long follow_hugetlb_page(struct mm_struct *, struct vm_area_struct *, - struct page **, struct vm_area_struct **, - unsigned long *, unsigned long *, long, unsigned int, - int *); + struct page **, unsigned long *, unsigned long *, + long, unsigned int, int *); void unmap_hugepage_range(struct vm_area_struct *, unsigned long, unsigned long, struct page *, zap_flags_t); @@ -306,9 +305,8 @@ static inline struct page *hugetlb_follow_page_mask(str= uct vm_area_struct *vma, =20 static inline long follow_hugetlb_page(struct mm_struct *mm, struct vm_area_struct *vma, struct page **pages, - struct vm_area_struct **vmas, unsigned long *position, - unsigned long *nr_pages, long i, unsigned int flags, - int *nonblocking) + unsigned long *position, unsigned long *nr_pages, + long i, unsigned int flags, int *nonblocking) { BUG(); return 0; diff --git a/mm/gup.c b/mm/gup.c index 36701b5f0123..dbe96d266670 100644 --- a/mm/gup.c +++ b/mm/gup.c @@ -1067,8 +1067,6 @@ static int check_vma_flags(struct vm_area_struct *vma= , unsigned long gup_flags) * @pages: array that receives pointers to the pages pinned. * Should be at least nr_pages long. Or NULL, if caller * only intends to ensure the pages are faulted in. - * @vmas: array of pointers to vmas corresponding to each page. - * Or NULL if the caller does not require them. * @locked: whether we're still with the mmap_lock held * * Returns either number of pages pinned (which may be less than the @@ -1082,8 +1080,6 @@ static int check_vma_flags(struct vm_area_struct *vma= , unsigned long gup_flags) * * The caller is responsible for releasing returned @pages, via put_page(). * - * @vmas are valid only as long as mmap_lock is held. - * * Must be called with mmap_lock held. It may be released. See below. * * __get_user_pages walks a process's page tables and takes a reference to @@ -1119,7 +1115,7 @@ static int check_vma_flags(struct vm_area_struct *vma= , unsigned long gup_flags) static long __get_user_pages(struct mm_struct *mm, unsigned long start, unsigned long nr_pages, unsigned int gup_flags, struct page **pages, - struct vm_area_struct **vmas, int *locked) + int *locked) { long ret =3D 0, i =3D 0; struct vm_area_struct *vma =3D NULL; @@ -1159,9 +1155,9 @@ static long __get_user_pages(struct mm_struct *mm, goto out; =20 if (is_vm_hugetlb_page(vma)) { - i =3D follow_hugetlb_page(mm, vma, pages, vmas, - &start, &nr_pages, i, - gup_flags, locked); + i =3D follow_hugetlb_page(mm, vma, pages, + &start, &nr_pages, i, + gup_flags, locked); if (!*locked) { /* * We've got a VM_FAULT_RETRY @@ -1226,10 +1222,6 @@ static long __get_user_pages(struct mm_struct *mm, ctx.page_mask =3D 0; } next_page: - if (vmas) { - vmas[i] =3D vma; - ctx.page_mask =3D 0; - } page_increm =3D 1 + (~(start >> PAGE_SHIFT) & ctx.page_mask); if (page_increm > nr_pages) page_increm =3D nr_pages; @@ -1384,7 +1376,6 @@ static __always_inline long __get_user_pages_locked(s= truct mm_struct *mm, unsigned long start, unsigned long nr_pages, struct page **pages, - struct vm_area_struct **vmas, int *locked, unsigned int flags) { @@ -1422,7 +1413,7 @@ static __always_inline long __get_user_pages_locked(s= truct mm_struct *mm, pages_done =3D 0; for (;;) { ret =3D __get_user_pages(mm, start, nr_pages, flags, pages, - vmas, locked); + locked); if (!(flags & FOLL_UNLOCKABLE)) { /* VM_FAULT_RETRY couldn't trigger, bypass */ pages_done =3D ret; @@ -1486,7 +1477,7 @@ static __always_inline long __get_user_pages_locked(s= truct mm_struct *mm, =20 *locked =3D 1; ret =3D __get_user_pages(mm, start, 1, flags | FOLL_TRIED, - pages, NULL, locked); + pages, locked); if (!*locked) { /* Continue to retry until we succeeded */ BUG_ON(ret !=3D 0); @@ -1584,7 +1575,7 @@ long populate_vma_page_range(struct vm_area_struct *v= ma, * not result in a stack expansion that recurses back here. */ ret =3D __get_user_pages(mm, start, nr_pages, gup_flags, - NULL, NULL, locked ? locked : &local_locked); + NULL, locked ? locked : &local_locked); lru_add_drain(); return ret; } @@ -1642,7 +1633,7 @@ long faultin_vma_page_range(struct vm_area_struct *vm= a, unsigned long start, return -EINVAL; =20 ret =3D __get_user_pages(mm, start, nr_pages, gup_flags, - NULL, NULL, locked); + NULL, locked); lru_add_drain(); return ret; } @@ -1710,8 +1701,7 @@ int __mm_populate(unsigned long start, unsigned long = len, int ignore_errors) #else /* CONFIG_MMU */ static long __get_user_pages_locked(struct mm_struct *mm, unsigned long st= art, unsigned long nr_pages, struct page **pages, - struct vm_area_struct **vmas, int *locked, - unsigned int foll_flags) + int *locked, unsigned int foll_flags) { struct vm_area_struct *vma; bool must_unlock =3D false; @@ -1755,8 +1745,7 @@ static long __get_user_pages_locked(struct mm_struct = *mm, unsigned long start, if (pages[i]) get_page(pages[i]); } - if (vmas) - vmas[i] =3D vma; + start =3D (start + PAGE_SIZE) & PAGE_MASK; } =20 @@ -1937,8 +1926,7 @@ struct page *get_dump_page(unsigned long addr) int locked =3D 0; int ret; =20 - ret =3D __get_user_pages_locked(current->mm, addr, 1, &page, NULL, - &locked, + ret =3D __get_user_pages_locked(current->mm, addr, 1, &page, &locked, FOLL_FORCE | FOLL_DUMP | FOLL_GET); return (ret =3D=3D 1) ? page : NULL; } @@ -2111,7 +2099,6 @@ static long __gup_longterm_locked(struct mm_struct *m= m, unsigned long start, unsigned long nr_pages, struct page **pages, - struct vm_area_struct **vmas, int *locked, unsigned int gup_flags) { @@ -2119,13 +2106,13 @@ static long __gup_longterm_locked(struct mm_struct = *mm, long rc, nr_pinned_pages; =20 if (!(gup_flags & FOLL_LONGTERM)) - return __get_user_pages_locked(mm, start, nr_pages, pages, vmas, + return __get_user_pages_locked(mm, start, nr_pages, pages, locked, gup_flags); =20 flags =3D memalloc_pin_save(); do { nr_pinned_pages =3D __get_user_pages_locked(mm, start, nr_pages, - pages, vmas, locked, + pages, locked, gup_flags); if (nr_pinned_pages <=3D 0) { rc =3D nr_pinned_pages; @@ -2143,9 +2130,8 @@ static long __gup_longterm_locked(struct mm_struct *m= m, * Check that the given flags are valid for the exported gup/pup interface= , and * update them with the required flags that the caller must have set. */ -static bool is_valid_gup_args(struct page **pages, struct vm_area_struct *= *vmas, - int *locked, unsigned int *gup_flags_p, - unsigned int to_set) +static bool is_valid_gup_args(struct page **pages, int *locked, + unsigned int *gup_flags_p, unsigned int to_set) { unsigned int gup_flags =3D *gup_flags_p; =20 @@ -2187,13 +2173,6 @@ static bool is_valid_gup_args(struct page **pages, s= truct vm_area_struct **vmas, (gup_flags & FOLL_PCI_P2PDMA))) return false; =20 - /* - * Can't use VMAs with locked, as locked allows GUP to unlock - * which invalidates the vmas array - */ - if (WARN_ON_ONCE(vmas && (gup_flags & FOLL_UNLOCKABLE))) - return false; - *gup_flags_p =3D gup_flags; return true; } @@ -2262,11 +2241,11 @@ long get_user_pages_remote(struct mm_struct *mm, { int local_locked =3D 1; =20 - if (!is_valid_gup_args(pages, NULL, locked, &gup_flags, + if (!is_valid_gup_args(pages, locked, &gup_flags, FOLL_TOUCH | FOLL_REMOTE)) return -EINVAL; =20 - return __get_user_pages_locked(mm, start, nr_pages, pages, NULL, + return __get_user_pages_locked(mm, start, nr_pages, pages, locked ? locked : &local_locked, gup_flags); } @@ -2301,11 +2280,11 @@ long get_user_pages(unsigned long start, unsigned l= ong nr_pages, { int locked =3D 1; =20 - if (!is_valid_gup_args(pages, NULL, NULL, &gup_flags, FOLL_TOUCH)) + if (!is_valid_gup_args(pages, NULL, &gup_flags, FOLL_TOUCH)) return -EINVAL; =20 return __get_user_pages_locked(current->mm, start, nr_pages, pages, - NULL, &locked, gup_flags); + &locked, gup_flags); } EXPORT_SYMBOL(get_user_pages); =20 @@ -2329,12 +2308,12 @@ long get_user_pages_unlocked(unsigned long start, u= nsigned long nr_pages, { int locked =3D 0; =20 - if (!is_valid_gup_args(pages, NULL, NULL, &gup_flags, + if (!is_valid_gup_args(pages, NULL, &gup_flags, FOLL_TOUCH | FOLL_UNLOCKABLE)) return -EINVAL; =20 return __get_user_pages_locked(current->mm, start, nr_pages, pages, - NULL, &locked, gup_flags); + &locked, gup_flags); } EXPORT_SYMBOL(get_user_pages_unlocked); =20 @@ -3124,7 +3103,7 @@ static int internal_get_user_pages_fast(unsigned long= start, start +=3D nr_pinned << PAGE_SHIFT; pages +=3D nr_pinned; ret =3D __gup_longterm_locked(current->mm, start, nr_pages - nr_pinned, - pages, NULL, &locked, + pages, &locked, gup_flags | FOLL_TOUCH | FOLL_UNLOCKABLE); if (ret < 0) { /* @@ -3166,7 +3145,7 @@ int get_user_pages_fast_only(unsigned long start, int= nr_pages, * FOLL_FAST_ONLY is required in order to match the API description of * this routine: no fall back to regular ("slow") GUP. */ - if (!is_valid_gup_args(pages, NULL, NULL, &gup_flags, + if (!is_valid_gup_args(pages, NULL, &gup_flags, FOLL_GET | FOLL_FAST_ONLY)) return -EINVAL; =20 @@ -3199,7 +3178,7 @@ int get_user_pages_fast(unsigned long start, int nr_p= ages, * FOLL_GET, because gup fast is always a "pin with a +1 page refcount" * request. */ - if (!is_valid_gup_args(pages, NULL, NULL, &gup_flags, FOLL_GET)) + if (!is_valid_gup_args(pages, NULL, &gup_flags, FOLL_GET)) return -EINVAL; return internal_get_user_pages_fast(start, nr_pages, gup_flags, pages); } @@ -3224,7 +3203,7 @@ EXPORT_SYMBOL_GPL(get_user_pages_fast); int pin_user_pages_fast(unsigned long start, int nr_pages, unsigned int gup_flags, struct page **pages) { - if (!is_valid_gup_args(pages, NULL, NULL, &gup_flags, FOLL_PIN)) + if (!is_valid_gup_args(pages, NULL, &gup_flags, FOLL_PIN)) return -EINVAL; return internal_get_user_pages_fast(start, nr_pages, gup_flags, pages); } @@ -3257,10 +3236,10 @@ long pin_user_pages_remote(struct mm_struct *mm, { int local_locked =3D 1; =20 - if (!is_valid_gup_args(pages, NULL, locked, &gup_flags, + if (!is_valid_gup_args(pages, locked, &gup_flags, FOLL_PIN | FOLL_TOUCH | FOLL_REMOTE)) return 0; - return __gup_longterm_locked(mm, start, nr_pages, pages, NULL, + return __gup_longterm_locked(mm, start, nr_pages, pages, locked ? locked : &local_locked, gup_flags); } @@ -3286,10 +3265,10 @@ long pin_user_pages(unsigned long start, unsigned l= ong nr_pages, { int locked =3D 1; =20 - if (!is_valid_gup_args(pages, NULL, NULL, &gup_flags, FOLL_PIN)) + if (!is_valid_gup_args(pages, NULL, &gup_flags, FOLL_PIN)) return 0; return __gup_longterm_locked(current->mm, start, nr_pages, - pages, NULL, &locked, gup_flags); + pages, &locked, gup_flags); } EXPORT_SYMBOL(pin_user_pages); =20 @@ -3303,11 +3282,11 @@ long pin_user_pages_unlocked(unsigned long start, u= nsigned long nr_pages, { int locked =3D 0; =20 - if (!is_valid_gup_args(pages, NULL, NULL, &gup_flags, + if (!is_valid_gup_args(pages, NULL, &gup_flags, FOLL_PIN | FOLL_TOUCH | FOLL_UNLOCKABLE)) return 0; =20 - return __gup_longterm_locked(current->mm, start, nr_pages, pages, NULL, + return __gup_longterm_locked(current->mm, start, nr_pages, pages, &locked, gup_flags); } EXPORT_SYMBOL(pin_user_pages_unlocked); diff --git a/mm/hugetlb.c b/mm/hugetlb.c index f154019e6b84..ea24718db4af 100644 --- a/mm/hugetlb.c +++ b/mm/hugetlb.c @@ -6425,17 +6425,14 @@ int hugetlb_mfill_atomic_pte(pte_t *dst_pte, } #endif /* CONFIG_USERFAULTFD */ =20 -static void record_subpages_vmas(struct page *page, struct vm_area_struct = *vma, - int refs, struct page **pages, - struct vm_area_struct **vmas) +static void record_subpages(struct page *page, struct vm_area_struct *vma, + int refs, struct page **pages) { int nr; =20 for (nr =3D 0; nr < refs; nr++) { if (likely(pages)) pages[nr] =3D nth_page(page, nr); - if (vmas) - vmas[nr] =3D vma; } } =20 @@ -6508,9 +6505,9 @@ struct page *hugetlb_follow_page_mask(struct vm_area_= struct *vma, } =20 long follow_hugetlb_page(struct mm_struct *mm, struct vm_area_struct *vma, - struct page **pages, struct vm_area_struct **vmas, - unsigned long *position, unsigned long *nr_pages, - long i, unsigned int flags, int *locked) + struct page **pages, unsigned long *position, + unsigned long *nr_pages, long i, unsigned int flags, + int *locked) { unsigned long pfn_offset; unsigned long vaddr =3D *position; @@ -6638,7 +6635,7 @@ long follow_hugetlb_page(struct mm_struct *mm, struct= vm_area_struct *vma, * If subpage information not requested, update counters * and skip the same_page loop below. */ - if (!pages && !vmas && !pfn_offset && + if (!pages && !pfn_offset && (vaddr + huge_page_size(h) < vma->vm_end) && (remainder >=3D pages_per_huge_page(h))) { vaddr +=3D huge_page_size(h); @@ -6653,11 +6650,10 @@ long follow_hugetlb_page(struct mm_struct *mm, stru= ct vm_area_struct *vma, refs =3D min3(pages_per_huge_page(h) - pfn_offset, remainder, (vma->vm_end - ALIGN_DOWN(vaddr, PAGE_SIZE)) >> PAGE_SHIFT); =20 - if (pages || vmas) - record_subpages_vmas(nth_page(page, pfn_offset), - vma, refs, - likely(pages) ? pages + i : NULL, - vmas ? vmas + i : NULL); + if (pages) + record_subpages(nth_page(page, pfn_offset), + vma, refs, + likely(pages) ? pages + i : NULL); =20 if (pages) { /* --=20 2.40.1