Merge branch 'x86/um-header' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip

* 'x86/um-header' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: (26 commits)
  x86: canonicalize remaining header guards
  x86: drop double underscores from header guards
  x86: Fix ASM_X86__ header guards
  x86, um: get rid of uml-config.h
  x86, um: get rid of arch/um/Kconfig.arch
  x86, um: get rid of arch/um/os symlink
  x86, um: get rid of excessive includes of uml-config.h
  x86, um: get rid of header symlinks
  x86, um: merge Kconfig.i386 and Kconfig.x86_64
  x86, um: get rid of sysdep symlink
  x86, um: trim the junk from uml ptrace-*.h
  x86, um: take vm-flags.h to sysdep
  x86, um: get rid of uml asm/arch
  x86, um: get rid of uml highmem.h
  x86, um: get rid of uml unistd.h
  x86, um: get rid of system.h -> system.h include
  x86, um: uml atomic.h is not needed anymore
  x86, um: untangle uml ldt.h
  x86, um: get rid of more uml asm/arch uses
  x86, um: remove dead header (uml module-generic.h; never used these days)
  ...

1 files changed, 42 insertions, 0 deletions

diff --git a/arch/x86/include/asm/pvclock-abi.h b/arch/x86/include/asm/pvclock-abi.h
new file mode 100644
index 00000000000..6d93508f262
--- /dev/null
+++ b/arch/x86/include/asm/pvclock-abi.h
@@ -0,0 +1,42 @@
+#ifndef _ASM_X86_PVCLOCK_ABI_H
+#define _ASM_X86_PVCLOCK_ABI_H
+#ifndef __ASSEMBLY__
+
+/*
+ * These structs MUST NOT be changed.
+ * They are the ABI between hypervisor and guest OS.
+ * Both Xen and KVM are using this.
+ *
+ * pvclock_vcpu_time_info holds the system time and the tsc timestamp
+ * of the last update. So the guest can use the tsc delta to get a
+ * more precise system time.  There is one per virtual cpu.
+ *
+ * pvclock_wall_clock references the point in time when the system
+ * time was zero (usually boot time), thus the guest calculates the
+ * current wall clock by adding the system time.
+ *
+ * Protocol for the "version" fields is: hypervisor raises it (making
+ * it uneven) before it starts updating the fields and raises it again
+ * (making it even) when it is done.  Thus the guest can make sure the
+ * time values it got are consistent by checking the version before
+ * and after reading them.
+ */
+
+struct pvclock_vcpu_time_info {
+	u32   version;
+	u32   pad0;
+	u64   tsc_timestamp;
+	u64   system_time;
+	u32   tsc_to_system_mul;
+	s8    tsc_shift;
+	u8    pad[3];
+} __attribute__((__packed__)); /* 32 bytes */
+
+struct pvclock_wall_clock {
+	u32   version;
+	u32   sec;
+	u32   nsec;
+} __attribute__((__packed__));
+
+#endif /* __ASSEMBLY__ */
+#endif /* _ASM_X86_PVCLOCK_ABI_H */