From b93590901a01a6d036b3b7c856bcc5724fdb9911 Mon Sep 17 00:00:00 2001 From: Andy Lutomirski Date: Tue, 23 Sep 2014 10:50:51 -0700 Subject: [PATCH] x86_64/vsyscall: Move all of the gate_area code to vsyscall_64.c This code exists for the sole purpose of making the vsyscall page look sort of like real userspace memory. Move it so that it lives with the rest of the vsyscall code. Signed-off-by: Andy Lutomirski Link: http://lkml.kernel.org/r/a7ee266773671a05f00b7175ca65a0dd812d2e4b.1411494540.git.luto@amacapital.net Signed-off-by: Ingo Molnar --- arch/x86/kernel/vsyscall_64.c | 49 +++++++++++++++++++++++++++++++++++ arch/x86/mm/init_64.c | 49 ----------------------------------- 2 files changed, 49 insertions(+), 49 deletions(-) diff --git a/arch/x86/kernel/vsyscall_64.c b/arch/x86/kernel/vsyscall_64.c index 957779f4eb40..521d5ed19547 100644 --- a/arch/x86/kernel/vsyscall_64.c +++ b/arch/x86/kernel/vsyscall_64.c @@ -283,6 +283,55 @@ sigsegv: return true; } +/* + * A pseudo VMA to allow ptrace access for the vsyscall page. This only + * covers the 64bit vsyscall page now. 32bit has a real VMA now and does + * not need special handling anymore: + */ +static const char *gate_vma_name(struct vm_area_struct *vma) +{ + return "[vsyscall]"; +} +static struct vm_operations_struct gate_vma_ops = { + .name = gate_vma_name, +}; +static struct vm_area_struct gate_vma = { + .vm_start = VSYSCALL_ADDR, + .vm_end = VSYSCALL_ADDR + PAGE_SIZE, + .vm_page_prot = PAGE_READONLY_EXEC, + .vm_flags = VM_READ | VM_EXEC, + .vm_ops = &gate_vma_ops, +}; + +struct vm_area_struct *get_gate_vma(struct mm_struct *mm) +{ +#ifdef CONFIG_IA32_EMULATION + if (!mm || mm->context.ia32_compat) + return NULL; +#endif + return &gate_vma; +} + +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); +} + +/* + * Use this when you have no reliable mm, typically from interrupt + * context. It is less reliable than using a task's mm and may give + * false positives. + */ +int in_gate_area_no_mm(unsigned long addr) +{ + return (addr & PAGE_MASK) == VSYSCALL_ADDR; +} + /* * Assume __initcall executes before all user space. Hopefully kmod * doesn't violate that. We'll find out if it does. diff --git a/arch/x86/mm/init_64.c b/arch/x86/mm/init_64.c index 4cb8763868fc..dd9ca9becc0f 100644 --- a/arch/x86/mm/init_64.c +++ b/arch/x86/mm/init_64.c @@ -1193,55 +1193,6 @@ int kern_addr_valid(unsigned long addr) return pfn_valid(pte_pfn(*pte)); } -/* - * A pseudo VMA to allow ptrace access for the vsyscall page. This only - * covers the 64bit vsyscall page now. 32bit has a real VMA now and does - * not need special handling anymore: - */ -static const char *gate_vma_name(struct vm_area_struct *vma) -{ - return "[vsyscall]"; -} -static struct vm_operations_struct gate_vma_ops = { - .name = gate_vma_name, -}; -static struct vm_area_struct gate_vma = { - .vm_start = VSYSCALL_ADDR, - .vm_end = VSYSCALL_ADDR + PAGE_SIZE, - .vm_page_prot = PAGE_READONLY_EXEC, - .vm_flags = VM_READ | VM_EXEC, - .vm_ops = &gate_vma_ops, -}; - -struct vm_area_struct *get_gate_vma(struct mm_struct *mm) -{ -#ifdef CONFIG_IA32_EMULATION - if (!mm || mm->context.ia32_compat) - return NULL; -#endif - return &gate_vma; -} - -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); -} - -/* - * Use this when you have no reliable mm, typically from interrupt - * context. It is less reliable than using a task's mm and may give - * false positives. - */ -int in_gate_area_no_mm(unsigned long addr) -{ - return (addr & PAGE_MASK) == VSYSCALL_ADDR; -} - static unsigned long probe_memory_block_size(void) { /* start from 2g */ -- 2.34.1