From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:35799) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1Yswz3-000314-0v for qemu-devel@nongnu.org; Thu, 14 May 2015 13:31:46 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1Yswz1-0005ly-EU for qemu-devel@nongnu.org; Thu, 14 May 2015 13:31:44 -0400 Received: from mx1.redhat.com ([209.132.183.28]:59230) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1Yswz1-0005lm-86 for qemu-devel@nongnu.org; Thu, 14 May 2015 13:31:43 -0400 From: Andrea Arcangeli 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> Subject: [Qemu-devel] [PATCH 04/23] userfaultfd: linux/userfaultfd_k.h List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , 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: zhang.zhanghailiang@huawei.com, Pavel Emelyanov , Johannes Weiner , Hugh Dickins , "Dr. David Alan Gilbert" , Sanidhya Kashyap , Dave Hansen , Andres Lagar-Cavilla , Mel Gorman , Paolo Bonzini , "Kirill A. Shutemov" , "Huangpeng (Peter)" , Andy Lutomirski , Linus Torvalds , Peter Feiner 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 */