diff options
author | H. Peter Anvin <hpa@zytor.com> | 2010-04-29 16:53:17 -0700 |
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committer | H. Peter Anvin <hpa@zytor.com> | 2010-04-29 16:53:17 -0700 |
commit | d9c5841e22231e4e49fd0a1004164e6fce59b7a6 (patch) | |
tree | e1f589c46b3ff79bbe7b1b2469f6362f94576da6 /arch/mips/kernel/vdso.c | |
parent | b701a47ba48b698976fb2fe05fb285b0edc1d26a (diff) | |
parent | 5967ed87ade85a421ef814296c3c7f182b08c225 (diff) |
Merge branch 'x86/asm' into x86/atomic
Merge reason:
Conflict between LOCK_PREFIX_HERE and relative alternatives
pointers
Resolved Conflicts:
arch/x86/include/asm/alternative.h
arch/x86/kernel/alternative.c
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
Diffstat (limited to 'arch/mips/kernel/vdso.c')
-rw-r--r-- | arch/mips/kernel/vdso.c | 112 |
1 files changed, 112 insertions, 0 deletions
diff --git a/arch/mips/kernel/vdso.c b/arch/mips/kernel/vdso.c new file mode 100644 index 00000000000..b773c1112b1 --- /dev/null +++ b/arch/mips/kernel/vdso.c @@ -0,0 +1,112 @@ +/* + * This file is subject to the terms and conditions of the GNU General Public + * License. See the file "COPYING" in the main directory of this archive + * for more details. + * + * Copyright (C) 2009, 2010 Cavium Networks, Inc. + */ + + +#include <linux/kernel.h> +#include <linux/err.h> +#include <linux/sched.h> +#include <linux/mm.h> +#include <linux/init.h> +#include <linux/binfmts.h> +#include <linux/elf.h> +#include <linux/vmalloc.h> +#include <linux/unistd.h> + +#include <asm/vdso.h> +#include <asm/uasm.h> + +/* + * Including <asm/unistd.h> would give use the 64-bit syscall numbers ... + */ +#define __NR_O32_sigreturn 4119 +#define __NR_O32_rt_sigreturn 4193 +#define __NR_N32_rt_sigreturn 6211 + +static struct page *vdso_page; + +static void __init install_trampoline(u32 *tramp, unsigned int sigreturn) +{ + uasm_i_addiu(&tramp, 2, 0, sigreturn); /* li v0, sigreturn */ + uasm_i_syscall(&tramp, 0); +} + +static int __init init_vdso(void) +{ + struct mips_vdso *vdso; + + vdso_page = alloc_page(GFP_KERNEL); + if (!vdso_page) + panic("Cannot allocate vdso"); + + vdso = vmap(&vdso_page, 1, 0, PAGE_KERNEL); + if (!vdso) + panic("Cannot map vdso"); + clear_page(vdso); + + install_trampoline(vdso->rt_signal_trampoline, __NR_rt_sigreturn); +#ifdef CONFIG_32BIT + install_trampoline(vdso->signal_trampoline, __NR_sigreturn); +#else + install_trampoline(vdso->n32_rt_signal_trampoline, + __NR_N32_rt_sigreturn); + install_trampoline(vdso->o32_signal_trampoline, __NR_O32_sigreturn); + install_trampoline(vdso->o32_rt_signal_trampoline, + __NR_O32_rt_sigreturn); +#endif + + vunmap(vdso); + + pr_notice("init_vdso successfull\n"); + + return 0; +} +device_initcall(init_vdso); + +static unsigned long vdso_addr(unsigned long start) +{ + return STACK_TOP; +} + +int arch_setup_additional_pages(struct linux_binprm *bprm, int uses_interp) +{ + int ret; + unsigned long addr; + struct mm_struct *mm = current->mm; + + down_write(&mm->mmap_sem); + + addr = vdso_addr(mm->start_stack); + + addr = get_unmapped_area(NULL, addr, PAGE_SIZE, 0, 0); + if (IS_ERR_VALUE(addr)) { + ret = addr; + goto up_fail; + } + + ret = install_special_mapping(mm, addr, PAGE_SIZE, + VM_READ|VM_EXEC| + VM_MAYREAD|VM_MAYWRITE|VM_MAYEXEC| + VM_ALWAYSDUMP, + &vdso_page); + + if (ret) + goto up_fail; + + mm->context.vdso = (void *)addr; + +up_fail: + up_write(&mm->mmap_sem); + return ret; +} + +const char *arch_vma_name(struct vm_area_struct *vma) +{ + if (vma->vm_mm && vma->vm_start == (long)vma->vm_mm->context.vdso) + return "[vdso]"; + return NULL; +} |