Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1422655AbbENRgY (ORCPT ); Thu, 14 May 2015 13:36:24 -0400 Received: from mx1.redhat.com ([209.132.183.28]:39009 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1161015AbbENRbt (ORCPT ); Thu, 14 May 2015 13:31:49 -0400 From: Andrea Arcangeli To: Andrew Morton , linux-kernel@vger.kernel.org, linux-mm@kvack.org, qemu-devel@nongnu.org, kvm@vger.kernel.org, linux-api@vger.kernel.org Cc: Pavel Emelyanov , Sanidhya Kashyap , zhang.zhanghailiang@huawei.com, Linus Torvalds , "Kirill A. Shutemov" , Andres Lagar-Cavilla , Dave Hansen , Paolo Bonzini , Rik van Riel , Mel Gorman , Andy Lutomirski , Hugh Dickins , Peter Feiner , "Dr. David Alan Gilbert" , Johannes Weiner , "Huangpeng (Peter)" Subject: [PATCH 04/23] userfaultfd: linux/userfaultfd_k.h Date: Thu, 14 May 2015 19:31:01 +0200 Message-Id: <1431624680-20153-5-git-send-email-aarcange@redhat.com> In-Reply-To: <1431624680-20153-1-git-send-email-aarcange@redhat.com> References: <1431624680-20153-1-git-send-email-aarcange@redhat.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2727 Lines: 99 Kernel header defining the methods needed by the VM common code to interact with the userfaultfd. Signed-off-by: Andrea Arcangeli --- include/linux/userfaultfd_k.h | 79 +++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 79 insertions(+) create mode 100644 include/linux/userfaultfd_k.h diff --git a/include/linux/userfaultfd_k.h b/include/linux/userfaultfd_k.h new file mode 100644 index 0000000..e1e4360 --- /dev/null +++ b/include/linux/userfaultfd_k.h @@ -0,0 +1,79 @@ +/* + * include/linux/userfaultfd_k.h + * + * Copyright (C) 2015 Red Hat, Inc. + * + */ + +#ifndef _LINUX_USERFAULTFD_K_H +#define _LINUX_USERFAULTFD_K_H + +#ifdef CONFIG_USERFAULTFD + +#include /* linux/include/uapi/linux/userfaultfd.h */ + +#include + +/* + * CAREFUL: Check include/uapi/asm-generic/fcntl.h when defining + * new flags, since they might collide with O_* ones. We want + * to re-use O_* flags that couldn't possibly have a meaning + * from userfaultfd, in order to leave a free define-space for + * shared O_* flags. + */ +#define UFFD_CLOEXEC O_CLOEXEC +#define UFFD_NONBLOCK O_NONBLOCK + +#define UFFD_SHARED_FCNTL_FLAGS (O_CLOEXEC | O_NONBLOCK) +#define UFFD_FLAGS_SET (EFD_SHARED_FCNTL_FLAGS) + +extern int handle_userfault(struct vm_area_struct *vma, unsigned long address, + unsigned int flags, unsigned long reason); + +/* mm helpers */ +static inline bool is_mergeable_vm_userfaultfd_ctx(struct vm_area_struct *vma, + struct vm_userfaultfd_ctx vm_ctx) +{ + return vma->vm_userfaultfd_ctx.ctx == vm_ctx.ctx; +} + +static inline bool userfaultfd_missing(struct vm_area_struct *vma) +{ + return vma->vm_flags & VM_UFFD_MISSING; +} + +static inline bool userfaultfd_armed(struct vm_area_struct *vma) +{ + return vma->vm_flags & (VM_UFFD_MISSING | VM_UFFD_WP); +} + +#else /* CONFIG_USERFAULTFD */ + +/* mm helpers */ +static inline int handle_userfault(struct vm_area_struct *vma, + unsigned long address, + unsigned int flags, + unsigned long reason) +{ + return VM_FAULT_SIGBUS; +} + +static inline bool is_mergeable_vm_userfaultfd_ctx(struct vm_area_struct *vma, + struct vm_userfaultfd_ctx vm_ctx) +{ + return true; +} + +static inline bool userfaultfd_missing(struct vm_area_struct *vma) +{ + return false; +} + +static inline bool userfaultfd_armed(struct vm_area_struct *vma) +{ + return false; +} + +#endif /* CONFIG_USERFAULTFD */ + +#endif /* _LINUX_USERFAULTFD_K_H */ -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/