4 files changed, 110 insertions, 15 deletions

diff --git a/arch/um/sys-i386/Makefile b/arch/um/sys-i386/Makefile
index 87b659d..3923cfb 100644
--- a/arch/um/sys-i386/Makefile
+++ b/arch/um/sys-i386/Makefile
@@ -4,7 +4,7 @@
 
 obj-y = bug.o bugs.o checksum.o delay.o fault.o ksyms.o ldt.o ptrace.o \
 	ptrace_user.o setjmp.o signal.o stub.o stub_segv.o syscalls.o sysrq.o \
-	sys_call_table.o tls.o atomic64_cx8_32.o
+	sys_call_table.o tls.o atomic64_cx8_32.o mem.o
 
 obj-$(CONFIG_BINFMT_ELF) += elfcore.o
 
diff --git a/arch/um/sys-i386/asm/elf.h b/arch/um/sys-i386/asm/elf.h
index d964a41..4230555 100644
--- a/arch/um/sys-i386/asm/elf.h
+++ b/arch/um/sys-i386/asm/elf.h
@@ -105,6 +105,8 @@ extern unsigned long __kernel_vsyscall;
 #define FIXADDR_USER_START      VSYSCALL_BASE
 #define FIXADDR_USER_END        VSYSCALL_END
 
+#define __HAVE_ARCH_GATE_AREA 1
+
 /*
  * Architecture-neutral AT_ values in 0-17, leave some room
  * for more of them, start the x86-specific ones at 32.
diff --git a/arch/um/sys-i386/delay.c b/arch/um/sys-i386/delay.c
index d623e07..f3fe1a6 100644
--- a/arch/um/sys-i386/delay.c
+++ b/arch/um/sys-i386/delay.c
@@ -1,29 +1,60 @@
+/*
+ * Copyright (C) 2011 Richard Weinberger <richrd@nod.at>
+ * Mostly copied from arch/x86/lib/delay.c
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+
 #include <linux/module.h>
 #include <linux/kernel.h>
 #include <linux/delay.h>
 #include <asm/param.h>
 
-void __delay(unsigned long time)
+void __delay(unsigned long loops)
 {
-	/* Stolen from the i386 __loop_delay */
-	int d0;
-	__asm__ __volatile__(
-		"\tjmp 1f\n"
+	asm volatile(
+		"test %0,%0\n"
+		"jz 3f\n"
+		"jmp 1f\n"
+
 		".align 16\n"
-		"1:\tjmp 2f\n"
+		"1: jmp 2f\n"
+
 		".align 16\n"
-		"2:\tdecl %0\n\tjns 2b"
-		:"=&a" (d0)
-		:"0" (time));
+		"2: dec %0\n"
+		" jnz 2b\n"
+		"3: dec %0\n"
+
+		: /* we don't need output */
+		: "a" (loops)
+	);
 }
+EXPORT_SYMBOL(__delay);
 
-void __udelay(unsigned long usecs)
+inline void __const_udelay(unsigned long xloops)
 {
-	int i, n;
+	int d0;
 
-	n = (loops_per_jiffy * HZ * usecs) / MILLION;
-        for(i=0;i<n;i++)
-                cpu_relax();
+	xloops *= 4;
+	asm("mull %%edx"
+		: "=d" (xloops), "=&a" (d0)
+		: "1" (xloops), "0"
+		(loops_per_jiffy * (HZ/4)));
+
+	__delay(++xloops);
 }
+EXPORT_SYMBOL(__const_udelay);
 
+void __udelay(unsigned long usecs)
+{
+	__const_udelay(usecs * 0x000010c7); /* 2**32 / 1000000 (rounded up) */
+}
 EXPORT_SYMBOL(__udelay);
+
+void __ndelay(unsigned long nsecs)
+{
+	__const_udelay(nsecs * 0x00005); /* 2**32 / 1000000000 (rounded up) */
+}
+EXPORT_SYMBOL(__ndelay);
diff --git a/arch/um/sys-i386/mem.c b/arch/um/sys-i386/mem.c
new file mode 100644
index 0000000..639900a
--- /dev/null
+++ b/arch/um/sys-i386/mem.c
@@ -0,0 +1,62 @@
+/*
+ * Copyright (C) 2011 Richard Weinberger <richrd@nod.at>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+
+#include <linux/mm.h>
+#include <asm/page.h>
+#include <asm/mman.h>
+
+static struct vm_area_struct gate_vma;
+
+static int __init gate_vma_init(void)
+{
+	if (!FIXADDR_USER_START)
+		return 0;
+
+	gate_vma.vm_mm = NULL;
+	gate_vma.vm_start = FIXADDR_USER_START;
+	gate_vma.vm_end = FIXADDR_USER_END;
+	gate_vma.vm_flags = VM_READ | VM_MAYREAD | VM_EXEC | VM_MAYEXEC;
+	gate_vma.vm_page_prot = __P101;
+
+	/*
+	 * Make sure the vDSO gets into every core dump.
+	 * Dumping its contents makes post-mortem fully interpretable later
+	 * without matching up the same kernel and hardware config to see
+	 * what PC values meant.
+	 */
+	gate_vma.vm_flags |= VM_ALWAYSDUMP;
+
+	return 0;
+}
+__initcall(gate_vma_init);
+
+struct vm_area_struct *get_gate_vma(struct mm_struct *mm)
+{
+	return FIXADDR_USER_START ? &gate_vma : NULL;
+}
+
+int in_gate_area_no_mm(unsigned long addr)
+{
+	if (!FIXADDR_USER_START)
+		return 0;
+
+	if ((addr >= FIXADDR_USER_START) && (addr < FIXADDR_USER_END))
+		return 1;
+
+	return 0;
+}
+
+int in_gate_area(struct mm_struct *mm, unsigned long addr)
+{
+	struct vm_area_struct *vma = get_gate_vma(mm);
+
+	if (!vma)
+		return 0;
+
+	return (addr >= vma->vm_start) && (addr < vma->vm_end);
+}