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authorIsaku Yamahata <yamahata@valinux.co.jp>2008-10-17 11:17:50 +0900
committerTony Luck <tony.luck@intel.com>2008-10-17 09:57:28 -0700
commit25c7bfaef201ab8cef400ea96e27803e1d32697a (patch)
treef3f2d626f868de472b51dde9a7e6bce4af9d4cc3 /arch/ia64
parentb31c09bd82731600a72c83894e7c6a53b36b6c83 (diff)
ia64/xen: add a necessary header file to compile include/xen/interface/xen.h
Create include/asm-ia64/pvclock-abi.h to compile which contains the same definitions of include/asm-x86/pvclock-abi.h because ia64/xen uses same structure. Hopefully include/asm-x86/pvclock-abi.h would be moved to somewhere more generic. Another approach is to include include/asm-x86/pvclock-abi.h from include/asm-ia64/pvclock-abi.h. But this would break if/when x86 header files are moved under arch/x86. So for now, same definitions are duplicated as suggested by Tony. Signed-off-by: Isaku Yamahata <yamahata@valinux.co.jp> Signed-off-by: Tony Luck <tony.luck@intel.com>
Diffstat (limited to 'arch/ia64')
-rw-r--r--arch/ia64/include/asm/pvclock-abi.h48
1 files changed, 48 insertions, 0 deletions
diff --git a/arch/ia64/include/asm/pvclock-abi.h b/arch/ia64/include/asm/pvclock-abi.h
new file mode 100644
index 00000000000..44ef9ef8f5b
--- /dev/null
+++ b/arch/ia64/include/asm/pvclock-abi.h
@@ -0,0 +1,48 @@
+/*
+ * same structure to x86's
+ * Hopefully asm-x86/pvclock-abi.h would be moved to somewhere more generic.
+ * For now, define same duplicated definitions.
+ */
+
+#ifndef _ASM_IA64__PVCLOCK_ABI_H
+#define _ASM_IA64__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_IA64__PVCLOCK_ABI_H */