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authorPavel Emelyanov2015-09-05 00:46:34 +0200
committerLinus Torvalds2015-09-05 01:54:41 +0200
commit3f602d2724b1f7d2d27ddcd7963a040a5890fd16 (patch)
treebb15462c57939ce4793c586b01e4218d2633a79a /include/uapi/linux/userfaultfd.h
parentuserfaultfd: add new syscall to provide memory externalization (diff)
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userfaultfd: Rename uffd_api.bits into .features
This is (seems to be) the minimal thing that is required to unblock standard uffd usage from the non-cooperative one. Now more bits can be added to the features field indicating e.g. UFFD_FEATURE_FORK and others needed for the latter use-case. Signed-off-by: Pavel Emelyanov <xemul@parallels.com> Signed-off-by: Andrea Arcangeli <aarcange@redhat.com> Cc: Sanidhya Kashyap <sanidhya.gatech@gmail.com> Cc: zhang.zhanghailiang@huawei.com Cc: "Kirill A. Shutemov" <kirill@shutemov.name> Cc: Andres Lagar-Cavilla <andreslc@google.com> Cc: Dave Hansen <dave.hansen@intel.com> Cc: Paolo Bonzini <pbonzini@redhat.com> Cc: Rik van Riel <riel@redhat.com> Cc: Mel Gorman <mgorman@suse.de> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Hugh Dickins <hughd@google.com> Cc: Peter Feiner <pfeiner@google.com> Cc: "Dr. David Alan Gilbert" <dgilbert@redhat.com> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: "Huangpeng (Peter)" <peter.huangpeng@huawei.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'include/uapi/linux/userfaultfd.h')
-rw-r--r--include/uapi/linux/userfaultfd.h12
1 files changed, 9 insertions, 3 deletions
diff --git a/include/uapi/linux/userfaultfd.h b/include/uapi/linux/userfaultfd.h
index 09c2e2a8c9d6..330206016249 100644
--- a/include/uapi/linux/userfaultfd.h
+++ b/include/uapi/linux/userfaultfd.h
@@ -12,8 +12,8 @@
#include <linux/types.h>
#define UFFD_API ((__u64)0xAA)
-/* FIXME: add "|UFFD_BIT_WP" to UFFD_API_BITS after implementing it */
-#define UFFD_API_BITS (UFFD_BIT_WRITE)
+/* FIXME: add "|UFFD_FEATURE_WP" to UFFD_API_FEATURES after implementing it */
+#define UFFD_API_FEATURES (UFFD_FEATURE_WRITE_BIT)
#define UFFD_API_IOCTLS \
((__u64)1 << _UFFDIO_REGISTER | \
(__u64)1 << _UFFDIO_UNREGISTER | \
@@ -53,12 +53,18 @@
#define UFFD_BIT_WP (1<<1) /* handle_userfault() reason VM_UFFD_WP */
#define UFFD_BITS 2 /* two above bits used for UFFD_BIT_* mask */
+/*
+ * Features reported in uffdio_api.features field
+ */
+#define UFFD_FEATURE_WRITE_BIT (1<<0) /* Corresponds to UFFD_BIT_WRITE */
+#define UFFD_FEATURE_WP_BIT (1<<1) /* Corresponds to UFFD_BIT_WP */
+
struct uffdio_api {
/* userland asks for an API number */
__u64 api;
/* kernel answers below with the available features for the API */
- __u64 bits;
+ __u64 features;
__u64 ioctls;
};