From 9ca8dbcc65cfc63d6f5ef3312a33184e1d726e00 Mon Sep 17 00:00:00 2001 From: Yunhong Jiang Date: Tue, 4 Aug 2015 12:17:53 -0700 Subject: Add the rt linux 4.1.3-rt3 as base Import the rt linux 4.1.3-rt3 as OPNFV kvm base. It's from git://git.kernel.org/pub/scm/linux/kernel/git/rt/linux-rt-devel.git linux-4.1.y-rt and the base is: commit 0917f823c59692d751951bf5ea699a2d1e2f26a2 Author: Sebastian Andrzej Siewior Date: Sat Jul 25 12:13:34 2015 +0200 Prepare v4.1.3-rt3 Signed-off-by: Sebastian Andrzej Siewior We lose all the git history this way and it's not good. We should apply another opnfv project repo in future. Change-Id: I87543d81c9df70d99c5001fbdf646b202c19f423 Signed-off-by: Yunhong Jiang --- kernel/arch/x86/lib/usercopy_64.c | 88 +++++++++++++++++++++++++++++++++++++++ 1 file changed, 88 insertions(+) create mode 100644 kernel/arch/x86/lib/usercopy_64.c (limited to 'kernel/arch/x86/lib/usercopy_64.c') diff --git a/kernel/arch/x86/lib/usercopy_64.c b/kernel/arch/x86/lib/usercopy_64.c new file mode 100644 index 000000000..0a42327a5 --- /dev/null +++ b/kernel/arch/x86/lib/usercopy_64.c @@ -0,0 +1,88 @@ +/* + * User address space access functions. + * + * Copyright 1997 Andi Kleen + * Copyright 1997 Linus Torvalds + * Copyright 2002 Andi Kleen + */ +#include +#include + +/* + * Zero Userspace + */ + +unsigned long __clear_user(void __user *addr, unsigned long size) +{ + long __d0; + might_fault(); + /* no memory constraint because it doesn't change any memory gcc knows + about */ + stac(); + asm volatile( + " testq %[size8],%[size8]\n" + " jz 4f\n" + "0: movq %[zero],(%[dst])\n" + " addq %[eight],%[dst]\n" + " decl %%ecx ; jnz 0b\n" + "4: movq %[size1],%%rcx\n" + " testl %%ecx,%%ecx\n" + " jz 2f\n" + "1: movb %b[zero],(%[dst])\n" + " incq %[dst]\n" + " decl %%ecx ; jnz 1b\n" + "2:\n" + ".section .fixup,\"ax\"\n" + "3: lea 0(%[size1],%[size8],8),%[size8]\n" + " jmp 2b\n" + ".previous\n" + _ASM_EXTABLE(0b,3b) + _ASM_EXTABLE(1b,2b) + : [size8] "=&c"(size), [dst] "=&D" (__d0) + : [size1] "r"(size & 7), "[size8]" (size / 8), "[dst]"(addr), + [zero] "r" (0UL), [eight] "r" (8UL)); + clac(); + return size; +} +EXPORT_SYMBOL(__clear_user); + +unsigned long clear_user(void __user *to, unsigned long n) +{ + if (access_ok(VERIFY_WRITE, to, n)) + return __clear_user(to, n); + return n; +} +EXPORT_SYMBOL(clear_user); + +unsigned long copy_in_user(void __user *to, const void __user *from, unsigned len) +{ + if (access_ok(VERIFY_WRITE, to, len) && access_ok(VERIFY_READ, from, len)) { + return copy_user_generic((__force void *)to, (__force void *)from, len); + } + return len; +} +EXPORT_SYMBOL(copy_in_user); + +/* + * Try to copy last bytes and clear the rest if needed. + * Since protection fault in copy_from/to_user is not a normal situation, + * it is not necessary to optimize tail handling. + */ +__visible unsigned long +copy_user_handle_tail(char *to, char *from, unsigned len) +{ + for (; len; --len, to++) { + char c; + + if (__get_user_nocheck(c, from++, sizeof(char))) + break; + if (__put_user_nocheck(c, to, sizeof(char))) + break; + } + clac(); + + /* If the destination is a kernel buffer, we always clear the end */ + if (!__addr_ok(to)) + memset(to, 0, len); + return len; +} -- cgit 1.2.3-korg