From mboxrd@z Thu Jan 1 00:00:00 1970 From: Andrew Morton Subject: [patch 036/166] userfaultfd: wp: userfaultfd_pte/huge_pmd_wp() helpers Date: Mon, 06 Apr 2020 20:05:37 -0700 Message-ID: <20200407030537.t3i5M-fCj%akpm@linux-foundation.org> References: <20200406200254.a69ebd9e08c4074e41ddebaf@linux-foundation.org> Reply-To: linux-kernel@vger.kernel.org Return-path: Received: from mail.kernel.org ([198.145.29.99]:49846 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726303AbgDGDFj (ORCPT ); Mon, 6 Apr 2020 23:05:39 -0400 In-Reply-To: <20200406200254.a69ebd9e08c4074e41ddebaf@linux-foundation.org> Sender: mm-commits-owner@vger.kernel.org List-Id: mm-commits@vger.kernel.org To: aarcange@redhat.com, akpm@linux-foundation.org, bgeffon@google.com, bobbypowers@gmail.com, cracauer@cons.org, david@redhat.com, dgilbert@redhat.com, dplotnikov@virtuozzo.com, gokhale2@llnl.gov, hannes@cmpxchg.org, hughd@google.com, jglisse@redhat.com, kirill@shutemov.name, linux-mm@kvack.org, mcfadden8@llnl.gov, mgorman@suse.de, mike.kravetz@oracle.com, mm-commits@vger.kernel.org, peterx@redhat.com, riel@redhat.com, rppt@linux.vnet.ibm.com, shli@fb.com, torvalds@linux-foundation.org, xemul@openvz.org From: Andrea Arcangeli Subject: userfaultfd: wp: userfaultfd_pte/huge_pmd_wp() helpers Implement helpers methods to invoke userfaultfd wp faults more selectively: not only when a wp fault triggers on a vma with vma->vm_flags VM_UFFD_WP set, but only if the _PAGE_UFFD_WP bit is set in the pagetable too. Link: http://lkml.kernel.org/r/20200220163112.11409-5-peterx@redhat.com Signed-off-by: Andrea Arcangeli Signed-off-by: Peter Xu Reviewed-by: Jerome Glisse Reviewed-by: Mike Rapoport Cc: Bobby Powers Cc: Brian Geffon Cc: David Hildenbrand Cc: Denis Plotnikov Cc: "Dr . David Alan Gilbert" Cc: Hugh Dickins Cc: Johannes Weiner Cc: "Kirill A . Shutemov" Cc: Martin Cracauer Cc: Marty McFadden Cc: Maya Gokhale Cc: Mel Gorman Cc: Mike Kravetz Cc: Pavel Emelyanov Cc: Rik van Riel Cc: Shaohua Li Signed-off-by: Andrew Morton --- include/linux/userfaultfd_k.h | 27 +++++++++++++++++++++++++++ 1 file changed, 27 insertions(+) --- a/include/linux/userfaultfd_k.h~userfaultfd-wp-userfaultfd_pte-huge_pmd_wp-helpers +++ a/include/linux/userfaultfd_k.h @@ -14,6 +14,8 @@ #include /* linux/include/uapi/linux/userfaultfd.h */ #include +#include +#include /* * CAREFUL: Check include/uapi/asm-generic/fcntl.h when defining @@ -57,6 +59,18 @@ static inline bool userfaultfd_wp(struct return vma->vm_flags & VM_UFFD_WP; } +static inline bool userfaultfd_pte_wp(struct vm_area_struct *vma, + pte_t pte) +{ + return userfaultfd_wp(vma) && pte_uffd_wp(pte); +} + +static inline bool userfaultfd_huge_pmd_wp(struct vm_area_struct *vma, + pmd_t pmd) +{ + return userfaultfd_wp(vma) && pmd_uffd_wp(pmd); +} + static inline bool userfaultfd_armed(struct vm_area_struct *vma) { return vma->vm_flags & (VM_UFFD_MISSING | VM_UFFD_WP); @@ -106,6 +120,19 @@ static inline bool userfaultfd_wp(struct return false; } +static inline bool userfaultfd_pte_wp(struct vm_area_struct *vma, + pte_t pte) +{ + return false; +} + +static inline bool userfaultfd_huge_pmd_wp(struct vm_area_struct *vma, + pmd_t pmd) +{ + return false; +} + + static inline bool userfaultfd_armed(struct vm_area_struct *vma) { return false; _