https://github.com/torvalds/linux
Tip revision: e8d018dd0257f744ca50a729e3d042cf2ec9da65 authored by Linus Torvalds on 19 March 2023, 20:27:55 UTC
Linux 6.3-rc3
Linux 6.3-rc3
Tip revision: e8d018d
usercopy.c
// SPDX-License-Identifier: GPL-2.0
// Copyright (C) 2018 Hangzhou C-SKY Microsystems co.,ltd.
#include <linux/uaccess.h>
#include <linux/types.h>
unsigned long raw_copy_from_user(void *to, const void *from,
unsigned long n)
{
int tmp, nsave;
__asm__ __volatile__(
"0: cmpnei %1, 0 \n"
" bf 7f \n"
" mov %3, %1 \n"
" or %3, %2 \n"
" andi %3, 3 \n"
" cmpnei %3, 0 \n"
" bf 1f \n"
" br 5f \n"
"1: cmplti %0, 16 \n"
" bt 3f \n"
"2: ldw %3, (%2, 0) \n"
"10: ldw %4, (%2, 4) \n"
" stw %3, (%1, 0) \n"
" stw %4, (%1, 4) \n"
"11: ldw %3, (%2, 8) \n"
"12: ldw %4, (%2, 12) \n"
" stw %3, (%1, 8) \n"
" stw %4, (%1, 12) \n"
" addi %2, 16 \n"
" addi %1, 16 \n"
" subi %0, 16 \n"
" br 1b \n"
"3: cmplti %0, 4 \n"
" bt 5f \n"
"4: ldw %3, (%2, 0) \n"
" stw %3, (%1, 0) \n"
" addi %2, 4 \n"
" addi %1, 4 \n"
" subi %0, 4 \n"
" br 3b \n"
"5: cmpnei %0, 0 \n"
" bf 7f \n"
"6: ldb %3, (%2, 0) \n"
" stb %3, (%1, 0) \n"
" addi %2, 1 \n"
" addi %1, 1 \n"
" subi %0, 1 \n"
" br 5b \n"
"8: stw %3, (%1, 0) \n"
" subi %0, 4 \n"
" bf 7f \n"
"9: subi %0, 8 \n"
" bf 7f \n"
"13: stw %3, (%1, 8) \n"
" subi %0, 12 \n"
" bf 7f \n"
".section __ex_table, \"a\" \n"
".align 2 \n"
".long 2b, 7f \n"
".long 4b, 7f \n"
".long 6b, 7f \n"
".long 10b, 8b \n"
".long 11b, 9b \n"
".long 12b,13b \n"
".previous \n"
"7: \n"
: "=r"(n), "=r"(to), "=r"(from), "=r"(nsave),
"=r"(tmp)
: "0"(n), "1"(to), "2"(from)
: "memory");
return n;
}
EXPORT_SYMBOL(raw_copy_from_user);
unsigned long raw_copy_to_user(void *to, const void *from,
unsigned long n)
{
int w0, w1, w2, w3;
__asm__ __volatile__(
"0: cmpnei %1, 0 \n"
" bf 8f \n"
" mov %3, %1 \n"
" or %3, %2 \n"
" andi %3, 3 \n"
" cmpnei %3, 0 \n"
" bf 1f \n"
" br 5f \n"
"1: cmplti %0, 16 \n" /* 4W */
" bt 3f \n"
" ldw %3, (%2, 0) \n"
" ldw %4, (%2, 4) \n"
" ldw %5, (%2, 8) \n"
" ldw %6, (%2, 12) \n"
"2: stw %3, (%1, 0) \n"
"9: stw %4, (%1, 4) \n"
"10: stw %5, (%1, 8) \n"
"11: stw %6, (%1, 12) \n"
" addi %2, 16 \n"
" addi %1, 16 \n"
" subi %0, 16 \n"
" br 1b \n"
"3: cmplti %0, 4 \n" /* 1W */
" bt 5f \n"
" ldw %3, (%2, 0) \n"
"4: stw %3, (%1, 0) \n"
" addi %2, 4 \n"
" addi %1, 4 \n"
" subi %0, 4 \n"
" br 3b \n"
"5: cmpnei %0, 0 \n" /* 1B */
" bf 13f \n"
" ldb %3, (%2, 0) \n"
"6: stb %3, (%1, 0) \n"
" addi %2, 1 \n"
" addi %1, 1 \n"
" subi %0, 1 \n"
" br 5b \n"
"7: subi %0, 4 \n"
"8: subi %0, 4 \n"
"12: subi %0, 4 \n"
" br 13f \n"
".section __ex_table, \"a\" \n"
".align 2 \n"
".long 2b, 13f \n"
".long 4b, 13f \n"
".long 6b, 13f \n"
".long 9b, 12b \n"
".long 10b, 8b \n"
".long 11b, 7b \n"
".previous \n"
"13: \n"
: "=r"(n), "=r"(to), "=r"(from), "=r"(w0),
"=r"(w1), "=r"(w2), "=r"(w3)
: "0"(n), "1"(to), "2"(from)
: "memory");
return n;
}
EXPORT_SYMBOL(raw_copy_to_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.
*
* Returns number of bytes that could not be cleared.
* On success, this will be zero.
*/
unsigned long
__clear_user(void __user *to, unsigned long n)
{
int data, value, tmp;
__asm__ __volatile__(
"0: cmpnei %1, 0 \n"
" bf 7f \n"
" mov %3, %1 \n"
" andi %3, 3 \n"
" cmpnei %3, 0 \n"
" bf 1f \n"
" br 5f \n"
"1: cmplti %0, 32 \n" /* 4W */
" bt 3f \n"
"8: stw %2, (%1, 0) \n"
"10: stw %2, (%1, 4) \n"
"11: stw %2, (%1, 8) \n"
"12: stw %2, (%1, 12) \n"
"13: stw %2, (%1, 16) \n"
"14: stw %2, (%1, 20) \n"
"15: stw %2, (%1, 24) \n"
"16: stw %2, (%1, 28) \n"
" addi %1, 32 \n"
" subi %0, 32 \n"
" br 1b \n"
"3: cmplti %0, 4 \n" /* 1W */
" bt 5f \n"
"4: stw %2, (%1, 0) \n"
" addi %1, 4 \n"
" subi %0, 4 \n"
" br 3b \n"
"5: cmpnei %0, 0 \n" /* 1B */
"9: bf 7f \n"
"6: stb %2, (%1, 0) \n"
" addi %1, 1 \n"
" subi %0, 1 \n"
" br 5b \n"
".section __ex_table,\"a\" \n"
".align 2 \n"
".long 8b, 9b \n"
".long 10b, 9b \n"
".long 11b, 9b \n"
".long 12b, 9b \n"
".long 13b, 9b \n"
".long 14b, 9b \n"
".long 15b, 9b \n"
".long 16b, 9b \n"
".long 4b, 9b \n"
".long 6b, 9b \n"
".previous \n"
"7: \n"
: "=r"(n), "=r" (data), "=r"(value), "=r"(tmp)
: "0"(n), "1"(to), "2"(0)
: "memory");
return n;
}
EXPORT_SYMBOL(__clear_user);