341 lines
10 KiB
C
341 lines
10 KiB
C
// SPDX-License-Identifier: GPL-2.0
|
|
/*
|
|
* User address space access functions.
|
|
* The non inlined parts of asm-i386/uaccess.h are here.
|
|
*
|
|
* Copyright 1997 Andi Kleen <ak@muc.de>
|
|
* Copyright 1997 Linus Torvalds
|
|
*/
|
|
#include <linux/export.h>
|
|
#include <linux/uaccess.h>
|
|
#include <asm/asm.h>
|
|
|
|
#ifdef CONFIG_X86_INTEL_USERCOPY
|
|
/*
|
|
* Alignment at which movsl is preferred for bulk memory copies.
|
|
*/
|
|
struct movsl_mask movsl_mask __read_mostly;
|
|
#endif
|
|
|
|
static inline int __movsl_is_ok(unsigned long a1, unsigned long a2, unsigned long n)
|
|
{
|
|
#ifdef CONFIG_X86_INTEL_USERCOPY
|
|
if (n >= 64 && ((a1 ^ a2) & movsl_mask.mask))
|
|
return 0;
|
|
#endif
|
|
return 1;
|
|
}
|
|
#define movsl_is_ok(a1, a2, n) \
|
|
__movsl_is_ok((unsigned long)(a1), (unsigned long)(a2), (n))
|
|
|
|
/*
|
|
* Zero Userspace
|
|
*/
|
|
|
|
#define __do_clear_user(addr,size) \
|
|
do { \
|
|
int __d0; \
|
|
might_fault(); \
|
|
__asm__ __volatile__( \
|
|
ASM_STAC "\n" \
|
|
"0: rep; stosl\n" \
|
|
" movl %2,%0\n" \
|
|
"1: rep; stosb\n" \
|
|
"2: " ASM_CLAC "\n" \
|
|
_ASM_EXTABLE_TYPE_REG(0b, 2b, EX_TYPE_UCOPY_LEN4, %2) \
|
|
_ASM_EXTABLE_UA(1b, 2b) \
|
|
: "=&c"(size), "=&D" (__d0) \
|
|
: "r"(size & 3), "0"(size / 4), "1"(addr), "a"(0)); \
|
|
} while (0)
|
|
|
|
/**
|
|
* clear_user - Zero a block of memory in user space.
|
|
* @to: Destination address, in user space.
|
|
* @n: Number of bytes to zero.
|
|
*
|
|
* Zero a block of memory in user space.
|
|
*
|
|
* Return: number of bytes that could not be cleared.
|
|
* On success, this will be zero.
|
|
*/
|
|
unsigned long
|
|
clear_user(void __user *to, unsigned long n)
|
|
{
|
|
might_fault();
|
|
if (access_ok(to, n))
|
|
__do_clear_user(to, n);
|
|
return n;
|
|
}
|
|
EXPORT_SYMBOL(clear_user);
|
|
|
|
/**
|
|
* __clear_user - Zero a block of memory in user space, with less checking.
|
|
* @to: Destination address, in user space.
|
|
* @n: Number of bytes to zero.
|
|
*
|
|
* Zero a block of memory in user space. Caller must check
|
|
* the specified block with access_ok() before calling this function.
|
|
*
|
|
* Return: number of bytes that could not be cleared.
|
|
* On success, this will be zero.
|
|
*/
|
|
unsigned long
|
|
__clear_user(void __user *to, unsigned long n)
|
|
{
|
|
__do_clear_user(to, n);
|
|
return n;
|
|
}
|
|
EXPORT_SYMBOL(__clear_user);
|
|
|
|
#ifdef CONFIG_X86_INTEL_USERCOPY
|
|
static unsigned long
|
|
__copy_user_intel(void __user *to, const void *from, unsigned long size)
|
|
{
|
|
int d0, d1;
|
|
__asm__ __volatile__(
|
|
" .align 2,0x90\n"
|
|
"1: movl 32(%4), %%eax\n"
|
|
" cmpl $67, %0\n"
|
|
" jbe 3f\n"
|
|
"2: movl 64(%4), %%eax\n"
|
|
" .align 2,0x90\n"
|
|
"3: movl 0(%4), %%eax\n"
|
|
"4: movl 4(%4), %%edx\n"
|
|
"5: movl %%eax, 0(%3)\n"
|
|
"6: movl %%edx, 4(%3)\n"
|
|
"7: movl 8(%4), %%eax\n"
|
|
"8: movl 12(%4),%%edx\n"
|
|
"9: movl %%eax, 8(%3)\n"
|
|
"10: movl %%edx, 12(%3)\n"
|
|
"11: movl 16(%4), %%eax\n"
|
|
"12: movl 20(%4), %%edx\n"
|
|
"13: movl %%eax, 16(%3)\n"
|
|
"14: movl %%edx, 20(%3)\n"
|
|
"15: movl 24(%4), %%eax\n"
|
|
"16: movl 28(%4), %%edx\n"
|
|
"17: movl %%eax, 24(%3)\n"
|
|
"18: movl %%edx, 28(%3)\n"
|
|
"19: movl 32(%4), %%eax\n"
|
|
"20: movl 36(%4), %%edx\n"
|
|
"21: movl %%eax, 32(%3)\n"
|
|
"22: movl %%edx, 36(%3)\n"
|
|
"23: movl 40(%4), %%eax\n"
|
|
"24: movl 44(%4), %%edx\n"
|
|
"25: movl %%eax, 40(%3)\n"
|
|
"26: movl %%edx, 44(%3)\n"
|
|
"27: movl 48(%4), %%eax\n"
|
|
"28: movl 52(%4), %%edx\n"
|
|
"29: movl %%eax, 48(%3)\n"
|
|
"30: movl %%edx, 52(%3)\n"
|
|
"31: movl 56(%4), %%eax\n"
|
|
"32: movl 60(%4), %%edx\n"
|
|
"33: movl %%eax, 56(%3)\n"
|
|
"34: movl %%edx, 60(%3)\n"
|
|
" addl $-64, %0\n"
|
|
" addl $64, %4\n"
|
|
" addl $64, %3\n"
|
|
" cmpl $63, %0\n"
|
|
" ja 1b\n"
|
|
"35: movl %0, %%eax\n"
|
|
" shrl $2, %0\n"
|
|
" andl $3, %%eax\n"
|
|
" cld\n"
|
|
"99: rep; movsl\n"
|
|
"36: movl %%eax, %0\n"
|
|
"37: rep; movsb\n"
|
|
"100:\n"
|
|
_ASM_EXTABLE_UA(1b, 100b)
|
|
_ASM_EXTABLE_UA(2b, 100b)
|
|
_ASM_EXTABLE_UA(3b, 100b)
|
|
_ASM_EXTABLE_UA(4b, 100b)
|
|
_ASM_EXTABLE_UA(5b, 100b)
|
|
_ASM_EXTABLE_UA(6b, 100b)
|
|
_ASM_EXTABLE_UA(7b, 100b)
|
|
_ASM_EXTABLE_UA(8b, 100b)
|
|
_ASM_EXTABLE_UA(9b, 100b)
|
|
_ASM_EXTABLE_UA(10b, 100b)
|
|
_ASM_EXTABLE_UA(11b, 100b)
|
|
_ASM_EXTABLE_UA(12b, 100b)
|
|
_ASM_EXTABLE_UA(13b, 100b)
|
|
_ASM_EXTABLE_UA(14b, 100b)
|
|
_ASM_EXTABLE_UA(15b, 100b)
|
|
_ASM_EXTABLE_UA(16b, 100b)
|
|
_ASM_EXTABLE_UA(17b, 100b)
|
|
_ASM_EXTABLE_UA(18b, 100b)
|
|
_ASM_EXTABLE_UA(19b, 100b)
|
|
_ASM_EXTABLE_UA(20b, 100b)
|
|
_ASM_EXTABLE_UA(21b, 100b)
|
|
_ASM_EXTABLE_UA(22b, 100b)
|
|
_ASM_EXTABLE_UA(23b, 100b)
|
|
_ASM_EXTABLE_UA(24b, 100b)
|
|
_ASM_EXTABLE_UA(25b, 100b)
|
|
_ASM_EXTABLE_UA(26b, 100b)
|
|
_ASM_EXTABLE_UA(27b, 100b)
|
|
_ASM_EXTABLE_UA(28b, 100b)
|
|
_ASM_EXTABLE_UA(29b, 100b)
|
|
_ASM_EXTABLE_UA(30b, 100b)
|
|
_ASM_EXTABLE_UA(31b, 100b)
|
|
_ASM_EXTABLE_UA(32b, 100b)
|
|
_ASM_EXTABLE_UA(33b, 100b)
|
|
_ASM_EXTABLE_UA(34b, 100b)
|
|
_ASM_EXTABLE_UA(35b, 100b)
|
|
_ASM_EXTABLE_UA(36b, 100b)
|
|
_ASM_EXTABLE_UA(37b, 100b)
|
|
_ASM_EXTABLE_TYPE_REG(99b, 100b, EX_TYPE_UCOPY_LEN4, %%eax)
|
|
: "=&c"(size), "=&D" (d0), "=&S" (d1)
|
|
: "1"(to), "2"(from), "0"(size)
|
|
: "eax", "edx", "memory");
|
|
return size;
|
|
}
|
|
|
|
static unsigned long __copy_user_intel_nocache(void *to,
|
|
const void __user *from, unsigned long size)
|
|
{
|
|
int d0, d1;
|
|
|
|
__asm__ __volatile__(
|
|
" .align 2,0x90\n"
|
|
"0: movl 32(%4), %%eax\n"
|
|
" cmpl $67, %0\n"
|
|
" jbe 2f\n"
|
|
"1: movl 64(%4), %%eax\n"
|
|
" .align 2,0x90\n"
|
|
"2: movl 0(%4), %%eax\n"
|
|
"21: movl 4(%4), %%edx\n"
|
|
" movnti %%eax, 0(%3)\n"
|
|
" movnti %%edx, 4(%3)\n"
|
|
"3: movl 8(%4), %%eax\n"
|
|
"31: movl 12(%4),%%edx\n"
|
|
" movnti %%eax, 8(%3)\n"
|
|
" movnti %%edx, 12(%3)\n"
|
|
"4: movl 16(%4), %%eax\n"
|
|
"41: movl 20(%4), %%edx\n"
|
|
" movnti %%eax, 16(%3)\n"
|
|
" movnti %%edx, 20(%3)\n"
|
|
"10: movl 24(%4), %%eax\n"
|
|
"51: movl 28(%4), %%edx\n"
|
|
" movnti %%eax, 24(%3)\n"
|
|
" movnti %%edx, 28(%3)\n"
|
|
"11: movl 32(%4), %%eax\n"
|
|
"61: movl 36(%4), %%edx\n"
|
|
" movnti %%eax, 32(%3)\n"
|
|
" movnti %%edx, 36(%3)\n"
|
|
"12: movl 40(%4), %%eax\n"
|
|
"71: movl 44(%4), %%edx\n"
|
|
" movnti %%eax, 40(%3)\n"
|
|
" movnti %%edx, 44(%3)\n"
|
|
"13: movl 48(%4), %%eax\n"
|
|
"81: movl 52(%4), %%edx\n"
|
|
" movnti %%eax, 48(%3)\n"
|
|
" movnti %%edx, 52(%3)\n"
|
|
"14: movl 56(%4), %%eax\n"
|
|
"91: movl 60(%4), %%edx\n"
|
|
" movnti %%eax, 56(%3)\n"
|
|
" movnti %%edx, 60(%3)\n"
|
|
" addl $-64, %0\n"
|
|
" addl $64, %4\n"
|
|
" addl $64, %3\n"
|
|
" cmpl $63, %0\n"
|
|
" ja 0b\n"
|
|
" sfence \n"
|
|
"5: movl %0, %%eax\n"
|
|
" shrl $2, %0\n"
|
|
" andl $3, %%eax\n"
|
|
" cld\n"
|
|
"6: rep; movsl\n"
|
|
" movl %%eax,%0\n"
|
|
"7: rep; movsb\n"
|
|
"8:\n"
|
|
_ASM_EXTABLE_UA(0b, 8b)
|
|
_ASM_EXTABLE_UA(1b, 8b)
|
|
_ASM_EXTABLE_UA(2b, 8b)
|
|
_ASM_EXTABLE_UA(21b, 8b)
|
|
_ASM_EXTABLE_UA(3b, 8b)
|
|
_ASM_EXTABLE_UA(31b, 8b)
|
|
_ASM_EXTABLE_UA(4b, 8b)
|
|
_ASM_EXTABLE_UA(41b, 8b)
|
|
_ASM_EXTABLE_UA(10b, 8b)
|
|
_ASM_EXTABLE_UA(51b, 8b)
|
|
_ASM_EXTABLE_UA(11b, 8b)
|
|
_ASM_EXTABLE_UA(61b, 8b)
|
|
_ASM_EXTABLE_UA(12b, 8b)
|
|
_ASM_EXTABLE_UA(71b, 8b)
|
|
_ASM_EXTABLE_UA(13b, 8b)
|
|
_ASM_EXTABLE_UA(81b, 8b)
|
|
_ASM_EXTABLE_UA(14b, 8b)
|
|
_ASM_EXTABLE_UA(91b, 8b)
|
|
_ASM_EXTABLE_TYPE_REG(6b, 8b, EX_TYPE_UCOPY_LEN4, %%eax)
|
|
_ASM_EXTABLE_UA(7b, 8b)
|
|
: "=&c"(size), "=&D" (d0), "=&S" (d1)
|
|
: "1"(to), "2"(from), "0"(size)
|
|
: "eax", "edx", "memory");
|
|
return size;
|
|
}
|
|
|
|
#else
|
|
|
|
/*
|
|
* Leave these declared but undefined. They should not be any references to
|
|
* them
|
|
*/
|
|
unsigned long __copy_user_intel(void __user *to, const void *from,
|
|
unsigned long size);
|
|
#endif /* CONFIG_X86_INTEL_USERCOPY */
|
|
|
|
/* Generic arbitrary sized copy. */
|
|
#define __copy_user(to, from, size) \
|
|
do { \
|
|
int __d0, __d1, __d2; \
|
|
__asm__ __volatile__( \
|
|
" cmp $7,%0\n" \
|
|
" jbe 1f\n" \
|
|
" movl %1,%0\n" \
|
|
" negl %0\n" \
|
|
" andl $7,%0\n" \
|
|
" subl %0,%3\n" \
|
|
"4: rep; movsb\n" \
|
|
" movl %3,%0\n" \
|
|
" shrl $2,%0\n" \
|
|
" andl $3,%3\n" \
|
|
" .align 2,0x90\n" \
|
|
"0: rep; movsl\n" \
|
|
" movl %3,%0\n" \
|
|
"1: rep; movsb\n" \
|
|
"2:\n" \
|
|
_ASM_EXTABLE_TYPE_REG(4b, 2b, EX_TYPE_UCOPY_LEN1, %3) \
|
|
_ASM_EXTABLE_TYPE_REG(0b, 2b, EX_TYPE_UCOPY_LEN4, %3) \
|
|
_ASM_EXTABLE_UA(1b, 2b) \
|
|
: "=&c"(size), "=&D" (__d0), "=&S" (__d1), "=r"(__d2) \
|
|
: "3"(size), "0"(size), "1"(to), "2"(from) \
|
|
: "memory"); \
|
|
} while (0)
|
|
|
|
unsigned long __copy_user_ll(void *to, const void *from, unsigned long n)
|
|
{
|
|
__uaccess_begin_nospec();
|
|
if (movsl_is_ok(to, from, n))
|
|
__copy_user(to, from, n);
|
|
else
|
|
n = __copy_user_intel(to, from, n);
|
|
__uaccess_end();
|
|
return n;
|
|
}
|
|
EXPORT_SYMBOL(__copy_user_ll);
|
|
|
|
unsigned long __copy_from_user_ll_nocache_nozero(void *to, const void __user *from,
|
|
unsigned long n)
|
|
{
|
|
__uaccess_begin_nospec();
|
|
#ifdef CONFIG_X86_INTEL_USERCOPY
|
|
if (n > 64 && static_cpu_has(X86_FEATURE_XMM2))
|
|
n = __copy_user_intel_nocache(to, from, n);
|
|
else
|
|
__copy_user(to, from, n);
|
|
#else
|
|
__copy_user(to, from, n);
|
|
#endif
|
|
__uaccess_end();
|
|
return n;
|
|
}
|
|
EXPORT_SYMBOL(__copy_from_user_ll_nocache_nozero);
|