diff options
author | Linus Torvalds <torvalds@ppc970.osdl.org> | 2005-04-16 15:20:36 -0700 |
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committer | Linus Torvalds <torvalds@ppc970.osdl.org> | 2005-04-16 15:20:36 -0700 |
commit | 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 (patch) | |
tree | 0bba044c4ce775e45a88a51686b5d9f90697ea9d /arch/i386/kernel/sysenter.c |
Linux-2.6.12-rc2v2.6.12-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!
Diffstat (limited to 'arch/i386/kernel/sysenter.c')
-rw-r--r-- | arch/i386/kernel/sysenter.c | 65 |
1 files changed, 65 insertions, 0 deletions
diff --git a/arch/i386/kernel/sysenter.c b/arch/i386/kernel/sysenter.c new file mode 100644 index 000000000000..960d8bd137d0 --- /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 <linux/init.h> +#include <linux/smp.h> +#include <linux/thread_info.h> +#include <linux/sched.h> +#include <linux/gfp.h> +#include <linux/string.h> +#include <linux/elf.h> + +#include <asm/cpufeature.h> +#include <asm/msr.h> +#include <asm/pgtable.h> +#include <asm/unistd.h> + +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); |