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authorYunhong Jiang <yunhong.jiang@intel.com>2015-08-04 12:17:53 -0700
committerYunhong Jiang <yunhong.jiang@intel.com>2015-08-04 15:44:42 -0700
commit9ca8dbcc65cfc63d6f5ef3312a33184e1d726e00 (patch)
tree1c9cafbcd35f783a87880a10f85d1a060db1a563 /kernel/arch/x86/include/asm/vvar.h
parent98260f3884f4a202f9ca5eabed40b1354c489b29 (diff)
Add the rt linux 4.1.3-rt3 as base
Import the rt linux 4.1.3-rt3 as OPNFV kvm base. It's from git://git.kernel.org/pub/scm/linux/kernel/git/rt/linux-rt-devel.git linux-4.1.y-rt and the base is: commit 0917f823c59692d751951bf5ea699a2d1e2f26a2 Author: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Date: Sat Jul 25 12:13:34 2015 +0200 Prepare v4.1.3-rt3 Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> We lose all the git history this way and it's not good. We should apply another opnfv project repo in future. Change-Id: I87543d81c9df70d99c5001fbdf646b202c19f423 Signed-off-by: Yunhong Jiang <yunhong.jiang@intel.com>
Diffstat (limited to 'kernel/arch/x86/include/asm/vvar.h')
-rw-r--r--kernel/arch/x86/include/asm/vvar.h51
1 files changed, 51 insertions, 0 deletions
diff --git a/kernel/arch/x86/include/asm/vvar.h b/kernel/arch/x86/include/asm/vvar.h
new file mode 100644
index 000000000..3f32dfc2a
--- /dev/null
+++ b/kernel/arch/x86/include/asm/vvar.h
@@ -0,0 +1,51 @@
+/*
+ * vvar.h: Shared vDSO/kernel variable declarations
+ * Copyright (c) 2011 Andy Lutomirski
+ * Subject to the GNU General Public License, version 2
+ *
+ * A handful of variables are accessible (read-only) from userspace
+ * code in the vsyscall page and the vdso. They are declared here.
+ * Some other file must define them with DEFINE_VVAR.
+ *
+ * In normal kernel code, they are used like any other variable.
+ * In user code, they are accessed through the VVAR macro.
+ *
+ * These variables live in a page of kernel data that has an extra RO
+ * mapping for userspace. Each variable needs a unique offset within
+ * that page; specify that offset with the DECLARE_VVAR macro. (If
+ * you mess up, the linker will catch it.)
+ */
+
+#ifndef _ASM_X86_VVAR_H
+#define _ASM_X86_VVAR_H
+
+#if defined(__VVAR_KERNEL_LDS)
+
+/* The kernel linker script defines its own magic to put vvars in the
+ * right place.
+ */
+#define DECLARE_VVAR(offset, type, name) \
+ EMIT_VVAR(name, offset)
+
+#else
+
+extern char __vvar_page;
+
+#define DECLARE_VVAR(offset, type, name) \
+ extern type vvar_ ## name __attribute__((visibility("hidden")));
+
+#define VVAR(name) (vvar_ ## name)
+
+#define DEFINE_VVAR(type, name) \
+ type name \
+ __attribute__((section(".vvar_" #name), aligned(16))) __visible
+
+#endif
+
+/* DECLARE_VVAR(offset, type, name) */
+
+DECLARE_VVAR(128, struct vsyscall_gtod_data, vsyscall_gtod_data)
+
+#undef DECLARE_VVAR
+
+#endif