From 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 Mon Sep 17 00:00:00 2001 From: Linus Torvalds Date: Sat, 16 Apr 2005 15:20:36 -0700 Subject: Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip! --- arch/i386/kernel/sysenter.c | 65 +++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 65 insertions(+) create mode 100644 arch/i386/kernel/sysenter.c (limited to 'arch/i386/kernel/sysenter.c') diff --git a/arch/i386/kernel/sysenter.c b/arch/i386/kernel/sysenter.c new file mode 100644 index 00000000000..960d8bd137d --- /dev/null +++ b/arch/i386/kernel/sysenter.c @@ -0,0 +1,65 @@ +/* + * linux/arch/i386/kernel/sysenter.c + * + * (C) Copyright 2002 Linus Torvalds + * + * This file contains the needed initializations to support sysenter. + */ + +#include +#include +#include +#include +#include +#include +#include + +#include +#include +#include +#include + +extern asmlinkage void sysenter_entry(void); + +void enable_sep_cpu(void *info) +{ + int cpu = get_cpu(); + struct tss_struct *tss = &per_cpu(init_tss, cpu); + + tss->ss1 = __KERNEL_CS; + tss->esp1 = sizeof(struct tss_struct) + (unsigned long) tss; + wrmsr(MSR_IA32_SYSENTER_CS, __KERNEL_CS, 0); + wrmsr(MSR_IA32_SYSENTER_ESP, tss->esp1, 0); + wrmsr(MSR_IA32_SYSENTER_EIP, (unsigned long) sysenter_entry, 0); + put_cpu(); +} + +/* + * These symbols are defined by vsyscall.o to mark the bounds + * of the ELF DSO images included therein. + */ +extern const char vsyscall_int80_start, vsyscall_int80_end; +extern const char vsyscall_sysenter_start, vsyscall_sysenter_end; + +static int __init sysenter_setup(void) +{ + void *page = (void *)get_zeroed_page(GFP_ATOMIC); + + __set_fixmap(FIX_VSYSCALL, __pa(page), PAGE_READONLY_EXEC); + + if (!boot_cpu_has(X86_FEATURE_SEP)) { + memcpy(page, + &vsyscall_int80_start, + &vsyscall_int80_end - &vsyscall_int80_start); + return 0; + } + + memcpy(page, + &vsyscall_sysenter_start, + &vsyscall_sysenter_end - &vsyscall_sysenter_start); + + on_each_cpu(enable_sep_cpu, NULL, 1, 1); + return 0; +} + +__initcall(sysenter_setup); -- cgit v1.2.3