commit f40c330091c7aa9956ab66f97a3abc8a68b67240
author Andy Lutomirski <luto@amacapital.net> Mon May 05 12:19:36 2014 -0700
committer H. Peter Anvin <hpa@linux.intel.com> Mon May 05 13:19:01 2014 -0700
tree b0c03dce9bf67eb15c98980a7323ca35122d10df
parent 18d0a6fd227177fd243993179c90e454d0638b06

x86, vdso: Move the vvar and hpet mappings next to the 64-bit vDSO

This makes the 64-bit and x32 vdsos use the same mechanism as the
32-bit vdso.  Most of the churn is deleting all the old fixmap code.

Signed-off-by: Andy Lutomirski <luto@amacapital.net>
Link: http://lkml.kernel.org/r/8af87023f57f6bb96ec8d17fce3f88018195b49b.1399317206.git.luto@amacapital.net
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>

arch/x86/mm/fault.c

diff --git a/arch/x86/mm/fault.c b/arch/x86/mm/fault.c
index 8e57229..858b47b 100644
--- a/arch/x86/mm/fault.c
+++ b/arch/x86/mm/fault.c
@@ -18,7 +18,8 @@
 #include <asm/traps.h>			/* dotraplinkage, ...		*/
 #include <asm/pgalloc.h>		/* pgd_*(), ...			*/
 #include <asm/kmemcheck.h>		/* kmemcheck_*(), ...		*/
-#include <asm/fixmap.h>			/* VSYSCALL_START		*/
+#include <asm/fixmap.h>			/* VSYSCALL_ADDR		*/
+#include <asm/vsyscall.h>		/* emulate_vsyscall		*/
 
 #define CREATE_TRACE_POINTS
 #include <asm/trace/exceptions.h>
@@ -771,7 +772,7 @@
 		 * emulation.
 		 */
 		if (unlikely((error_code & PF_INSTR) &&
-			     ((address & ~0xfff) == VSYSCALL_START))) {
+			     ((address & ~0xfff) == VSYSCALL_ADDR))) {
 			if (emulate_vsyscall(regs, address))
 				return;
 		}

arch/x86/mm/init_64.c

diff --git a/arch/x86/mm/init_64.c b/arch/x86/mm/init_64.c
index 5638496..6f88184 100644
--- a/arch/x86/mm/init_64.c
+++ b/arch/x86/mm/init_64.c
@@ -1055,8 +1055,8 @@
 	after_bootmem = 1;
 
 	/* Register memory areas for /proc/kcore */
-	kclist_add(&kcore_vsyscall, (void *)VSYSCALL_START,
-			 VSYSCALL_END - VSYSCALL_START, KCORE_OTHER);
+	kclist_add(&kcore_vsyscall, (void *)VSYSCALL_ADDR,
+			 PAGE_SIZE, KCORE_OTHER);
 
 	mem_init_print_info(NULL);
 }
@@ -1186,8 +1186,8 @@
  * not need special handling anymore:
  */
 static struct vm_area_struct gate_vma = {
-	.vm_start	= VSYSCALL_START,
-	.vm_end		= VSYSCALL_START + (VSYSCALL_MAPPED_PAGES * PAGE_SIZE),
+	.vm_start	= VSYSCALL_ADDR,
+	.vm_end		= VSYSCALL_ADDR + PAGE_SIZE,
 	.vm_page_prot	= PAGE_READONLY_EXEC,
 	.vm_flags	= VM_READ | VM_EXEC
 };
@@ -1218,7 +1218,7 @@
  */
 int in_gate_area_no_mm(unsigned long addr)
 {
-	return (addr >= VSYSCALL_START) && (addr < VSYSCALL_END);
+	return (addr & PAGE_MASK) == VSYSCALL_ADDR;
 }
 
 const char *arch_vma_name(struct vm_area_struct *vma)