From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:40371) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1YTZQT-00045D-LN for qemu-devel@nongnu.org; Thu, 05 Mar 2015 12:19:10 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1YTZQQ-0007c5-SZ for qemu-devel@nongnu.org; Thu, 05 Mar 2015 12:19:09 -0500 Received: from mx1.redhat.com ([209.132.183.28]:59658) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1YTZQQ-0007bL-KS for qemu-devel@nongnu.org; Thu, 05 Mar 2015 12:19:06 -0500 From: Andrea Arcangeli Date: Thu, 5 Mar 2015 18:17:49 +0100 Message-Id: <1425575884-2574-7-git-send-email-aarcange@redhat.com> In-Reply-To: <1425575884-2574-1-git-send-email-aarcange@redhat.com> References: <1425575884-2574-1-git-send-email-aarcange@redhat.com> Subject: [Qemu-devel] [PATCH 06/21] userfaultfd: add VM_UFFD_MISSING and VM_UFFD_WP List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: qemu-devel@nongnu.org, kvm@vger.kernel.org, linux-kernel@vger.kernel.org, linux-mm@kvack.org, linux-api@vger.kernel.org, Android Kernel Team Cc: Robert Love , Dave Hansen , Jan Kara , Neil Brown , Stefan Hajnoczi , Andrew Jones , Sanidhya Kashyap , KOSAKI Motohiro , Michel Lespinasse , Taras Glek , zhang.zhanghailiang@huawei.com, Pavel Emelyanov , Hugh Dickins , Mel Gorman , Sasha Levin , "Dr. David Alan Gilbert" , "Huangpeng (Peter)" , Andres Lagar-Cavilla , Christopher Covington , Anthony Liguori , Paolo Bonzini , "Kirill A. Shutemov" , Keith Packard , Wenchao Xia , Juan Quintela , Andy Lutomirski , Minchan Kim , Dmitry Adamushko , Johannes Weiner , Mike Hommey , Andrew Morton , Linus Torvalds , Peter Feiner These two flags gets set in vma->vm_flags to tell the VM common code if the userfaultfd is armed and in which mode (only tracking missing faults, only tracking wrprotect faults or both). If neither flags is set it means the userfaultfd is not armed on the vma. Signed-off-by: Andrea Arcangeli --- include/linux/mm.h | 2 ++ kernel/fork.c | 2 +- 2 files changed, 3 insertions(+), 1 deletion(-) diff --git a/include/linux/mm.h b/include/linux/mm.h index 47a9392..762ef9d 100644 --- a/include/linux/mm.h +++ b/include/linux/mm.h @@ -123,8 +123,10 @@ extern unsigned int kobjsize(const void *objp); #define VM_MAYSHARE 0x00000080 #define VM_GROWSDOWN 0x00000100 /* general info on the segment */ +#define VM_UFFD_MISSING 0x00000200 /* missing pages tracking */ #define VM_PFNMAP 0x00000400 /* Page-ranges managed without "struct page", just pure PFN */ #define VM_DENYWRITE 0x00000800 /* ETXTBSY on write attempts.. */ +#define VM_UFFD_WP 0x00001000 /* wrprotect pages tracking */ #define VM_LOCKED 0x00002000 #define VM_IO 0x00004000 /* Memory mapped I/O or similar */ diff --git a/kernel/fork.c b/kernel/fork.c index cb215c0..cfab6e9 100644 --- a/kernel/fork.c +++ b/kernel/fork.c @@ -423,7 +423,7 @@ static int dup_mmap(struct mm_struct *mm, struct mm_struct *oldmm) tmp->vm_mm = mm; if (anon_vma_fork(tmp, mpnt)) goto fail_nomem_anon_vma_fork; - tmp->vm_flags &= ~VM_LOCKED; + tmp->vm_flags &= ~(VM_LOCKED|VM_UFFD_MISSING|VM_UFFD_WP); tmp->vm_next = tmp->vm_prev = NULL; tmp->vm_userfaultfd_ctx = NULL_VM_UFFD_CTX; file = tmp->vm_file;