diff options
| author | Linus Torvalds <torvalds@linux-foundation.org> | 2010-04-12 18:36:11 -0700 |
|---|---|---|
| committer | Linus Torvalds <torvalds@linux-foundation.org> | 2010-04-12 18:36:11 -0700 |
| commit | 4505a4938917f4872efcc90bc1e5f4f0ce903b47 (patch) | |
| tree | e049aed70101694b599ae53e6f56bff66d37f8a7 /arch/mips/kernel/vdso.c | |
| parent | fedfb947b2235c1085df97cf52f688b808c3a515 (diff) | |
| parent | f6be75d03c8870be91e6e2a195648ece04b6bb16 (diff) | |
Merge branch 'upstream' of git://ftp.linux-mips.org/pub/scm/upstream-linus
* 'upstream' of git://ftp.linux-mips.org/pub/scm/upstream-linus: (36 commits)
MIPS: Calculate proper ebase value for 64-bit kernels
MIPS: Alchemy: DB1200: Remove custom wait implementation
MIPS: Big Sur: Make defconfig more useful.
MIPS: Fix __vmalloc() etc. on MIPS for non-GPL modules
MIPS: Sibyte: Fix M3 TLB exception handler workaround.
MIPS: BCM63xx: Fix build failure in board_bcm963xx.c
MIPS: uasm: Add OR instruction.
MIPS: Sibyte: Apply M3 workaround only on affected chip types and versions.
MIPS: BCM63xx: Initialize gpio_out_low & out_high to current value at boot.
MIPS: BCM63xx: Register SSB SPROM fallback in board's first stage callback
MIPS: BCM63xx: Fix typo in cpu-feature-overrides file.
MIPS: BCM63xx: Add support for second uart.
MIPS: BCM63xx: Fix double gpio registration.
MIPS: BCM63xx: Add DWVS0 board
MIPS: BCM63xx: Add the RTA1025W-16 BCM6348-based board to suppported boards.
MIPS: BCM63xx: Fix BCM6338 and BCM6345 gpio count
MIPS: libgcc.h: Checkpatch cleanup
MIPS: Loongson-2F: Flush the branch target history in BTB and RAS
MIPS: Move signal trampolines off of the stack.
MIPS: Preliminary VDSO
...
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; +} |
