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/* SPDX-License-Identifier: GPL-2.0-only */
/*
* Copyright (C) 2004, 2007-2010, 2011-2012 Synopsys, Inc. (www.synopsys.com)
*
* vineetg: June 2010
* -__clear_user( ) called multiple times during elf load was byte loop
* converted to do as much word clear as possible.
*
* vineetg: Dec 2009
* -Hand crafted constant propagation for "constant" copy sizes
* -stock kernel shrunk by 33K at -O3
*
* vineetg: Sept 2009
* -Added option to (UN)inline copy_(to|from)_user to reduce code sz
* -kernel shrunk by 200K even at -O3 (gcc 4.2.1)
* -Enabled when doing -Os
*
* Amit Bhor, Sameer Dhavale: Codito Technologies 2004
*/
#ifndef _ASM_ARC_UACCESS_H
#define _ASM_ARC_UACCESS_H
#include <linux/string.h> /* for generic string functions */
#define __kernel_ok (uaccess_kernel())
/*
* Algorithmically, for __user_ok() we want do:
* (start < TASK_SIZE) && (start+len < TASK_SIZE)
* where TASK_SIZE could either be retrieved from thread_info->addr_limit or
* emitted directly in code.
*
* This can however be rewritten as follows:
* (len <= TASK_SIZE) && (start+len < TASK_SIZE)
*
* Because it essentially checks if buffer end is within limit and @len is
* non-ngeative, which implies that buffer start will be within limit too.
*
* The reason for rewriting being, for majority of cases, @len is generally
* compile time constant, causing first sub-expression to be compile time
* subsumed.
*
* The second part would generate weird large LIMMs e.g. (0x6000_0000 - 0x10),
* so we check for TASK_SIZE using get_fs() since the addr_limit load from mem
* would already have been done at this call site for __kernel_ok()
*
*/
#define __user_ok(addr, sz) (((sz) <= TASK_SIZE) && \
((addr) <= (get_fs() - (sz))))
#define __access_ok(addr, sz) (unlikely(__kernel_ok) || \
likely(__user_ok((addr), (sz))))
/*********** Single byte/hword/word copies ******************/
#define __get_user_fn(sz, u, k) \
({ \
long __ret = 0; /* success by default */ \
switch (sz) { \
case 1: __arc_get_user_one(*(k), u, "ldb", __ret); break; \
case 2: __arc_get_user_one(*(k), u, "ldw", __ret); break; \
case 4: __arc_get_user_one(*(k), u, "ld", __ret); break; \
case 8: __arc_get_user_one_64(*(k), u, __ret); break; \
} \
__ret; \
})
/*
* Returns 0 on success, -EFAULT if not.
* @ret already contains 0 - given that errors will be less likely
* (hence +r asm constraint below).
* In case of error, fixup code will make it -EFAULT
*/
#define __arc_get_user_one(dst, src, op, ret) \
__asm__ __volatile__( \
"1: "op" %1,[%2]\n" \
"2: ;nop\n" \
" .section .fixup, \"ax\"\n" \
" .align 4\n" \
"3: # return -EFAULT\n" \
" mov %0, %3\n" \
" # zero out dst ptr\n" \
" mov %1, 0\n" \
" j 2b\n" \
" .previous\n" \
" .section __ex_table, \"a\"\n" \
" .align 4\n" \
" .word 1b,3b\n" \
" .previous\n" \
\
: "+r" (ret), "=r" (dst) \
: "r" (src), "ir" (-EFAULT))
#define __arc_get_user_one_64(dst, src, ret) \
__asm__ __volatile__( \
"1: ld %1,[%2]\n" \
"4: ld %R1,[%2, 4]\n" \
"2: ;nop\n" \
" .section .fixup, \"ax\"\n" \
" .align 4\n" \
"3: # return -EFAULT\n" \
" mov %0, %3\n" \
" # zero out dst ptr\n" \
" mov %1, 0\n" \
" mov %R1, 0\n" \
" j 2b\n" \
" .previous\n" \
" .section __ex_table, \"a\"\n" \
" .align 4\n" \
" .word 1b,3b\n" \
" .word 4b,3b\n" \
" .previous\n" \
\
: "+r" (ret), "=r" (dst) \
: "r" (src), "ir" (-EFAULT))
#define __put_user_fn(sz, u, k) \
({ \
long __ret = 0; /* success by default */ \
switch (sz) { \
case 1: __arc_put_user_one(*(k), u, "stb", __ret); break; \
case 2: __arc_put_user_one(*(k), u, "stw", __ret); break; \
case 4: __arc_put_user_one(*(k), u, "st", __ret); break; \
case 8: __arc_put_user_one_64(*(k), u, __ret); break; \
} \
__ret; \
})
#define __arc_put_user_one(src, dst, op, ret) \
__asm__ __volatile__( \
"1: "op" %1,[%2]\n" \
"2: ;nop\n" \
" .section .fixup, \"ax\"\n" \
" .align 4\n" \
"3: mov %0, %3\n" \
" j 2b\n" \
" .previous\n" \
" .section __ex_table, \"a\"\n" \
" .align 4\n" \
" .word 1b,3b\n" \
" .previous\n" \
\
: "+r" (ret) \
: "r" (src), "r" (dst), "ir" (-EFAULT))
#define __arc_put_user_one_64(src, dst, ret) \
__asm__ __volatile__( \
"1: st %1,[%2]\n" \
"4: st %R1,[%2, 4]\n" \
"2: ;nop\n" \
" .section .fixup, \"ax\"\n" \
" .align 4\n" \
"3: mov %0, %3\n" \
" j 2b\n" \
" .previous\n" \
" .section __ex_table, \"a\"\n" \
" .align 4\n" \
" .word 1b,3b\n" \
" .word 4b,3b\n" \
" .previous\n" \
\
: "+r" (ret) \
: "r" (src), "r" (dst), "ir" (-EFAULT))
static inline unsigned long
raw_copy_from_user(void *to, const void __user *from, unsigned long n)
{
long res = 0;
char val;
unsigned long tmp1, tmp2, tmp3, tmp4;
unsigned long orig_n = n;
if (n == 0)
return 0;
/* unaligned */
if (((unsigned long)to & 0x3) || ((unsigned long)from & 0x3)) {
unsigned char tmp;
__asm__ __volatile__ (
" mov.f lp_count, %0 \n"
" lpnz 2f \n"
"1: ldb.ab %1, [%3, 1] \n"
" stb.ab %1, [%2, 1] \n"
" sub %0,%0,1 \n"
"2: ;nop \n"
" .section .fixup, \"ax\" \n"
" .align 4 \n"
"3: j 2b \n"
" .previous \n"
" .section __ex_table, \"a\" \n"
" .align 4 \n"
" .word 1b, 3b \n"
" .previous \n"
: "+r" (n),
/*
* Note as an '&' earlyclobber operand to make sure the
* temporary register inside the loop is not the same as
* FROM or TO.
*/
"=&r" (tmp), "+r" (to), "+r" (from)
:
: "lp_count", "memory");
return n;
}
/*
* Hand-crafted constant propagation to reduce code sz of the
* laddered copy 16x,8,4,2,1
*/
if (__builtin_constant_p(orig_n)) {
res = orig_n;
if (orig_n / 16) {
orig_n = orig_n % 16;
__asm__ __volatile__(
" lsr lp_count, %7,4 \n"
" lp 3f \n"
"1: ld.ab %3, [%2, 4] \n"
"11: ld.ab %4, [%2, 4] \n"
"12: ld.ab %5, [%2, 4] \n"
"13: ld.ab %6, [%2, 4] \n"
" st.ab %3, [%1, 4] \n"
" st.ab %4, [%1, 4] \n"
" st.ab %5, [%1, 4] \n"
" st.ab %6, [%1, 4] \n"
" sub %0,%0,16 \n"
"3: ;nop \n"
" .section .fixup, \"ax\" \n"
" .align 4 \n"
"4: j 3b \n"
" .previous \n"
" .section __ex_table, \"a\" \n"
" .align 4 \n"
" .word 1b, 4b \n"
" .word 11b,4b \n"
" .word 12b,4b \n"
" .word 13b,4b \n"
" .previous \n"
: "+r" (res), "+r"(to), "+r"(from),
"=r"(tmp1), "=r"(tmp2), "=r"(tmp3), "=r"(tmp4)
: "ir"(n)
: "lp_count", "memory");
}
if (orig_n / 8) {
orig_n = orig_n % 8;
__asm__ __volatile__(
"14: ld.ab %3, [%2,4] \n"
"15: ld.ab %4, [%2,4] \n"
" st.ab %3, [%1,4] \n"
" st.ab %4, [%1,4] \n"
" sub %0,%0,8 \n"
"31: ;nop \n"
" .section .fixup, \"ax\" \n"
" .align 4 \n"
"4: j 31b \n"
" .previous \n"
" .section __ex_table, \"a\" \n"
" .align 4 \n"
" .word 14b,4b \n"
" .word 15b,4b \n"
" .previous \n"
: "+r" (res), "+r"(to), "+r"(from),
"=r"(tmp1), "=r"(tmp2)
:
: "memory");
}
if (orig_n / 4) {
orig_n = orig_n % 4;
__asm__ __volatile__(
"16: ld.ab %3, [%2,4] \n"
" st.ab %3, [%1,4] \n"
" sub %0,%0,4 \n"
"32: ;nop \n"
" .section .fixup, \"ax\" \n"
" .align 4 \n"
"4: j 32b \n"
" .previous \n"
" .section __ex_table, \"a\" \n"
" .align 4 \n"
" .word 16b,4b \n"
" .previous \n"
: "+r" (res), "+r"(to), "+r"(from), "=r"(tmp1)
:
: "memory");
}
if (orig_n / 2) {
orig_n = orig_n % 2;
__asm__ __volatile__(
"17: ldw.ab %3, [%2,2] \n"
" stw.ab %3, [%1,2] \n"
" sub %0,%0,2 \n"
"33: ;nop \n"
" .section .fixup, \"ax\" \n"
" .align 4 \n"
"4: j 33b \n"
" .previous \n"
" .section __ex_table, \"a\" \n"
" .align 4 \n"
" .word 17b,4b \n"
" .previous \n"
: "+r" (res), "+r"(to), "+r"(from), "=r"(tmp1)
:
: "memory");
}
if (orig_n & 1) {
__asm__ __volatile__(
"18: ldb.ab %3, [%2,2] \n"
" stb.ab %3, [%1,2] \n"
" sub %0,%0,1 \n"
"34: ; nop \n"
" .section .fixup, \"ax\" \n"
" .align 4 \n"
"4: j 34b \n"
" .previous \n"
" .section __ex_table, \"a\" \n"
" .align 4 \n"
" .word 18b,4b \n"
" .previous \n"
: "+r" (res), "+r"(to), "+r"(from), "=r"(tmp1)
:
: "memory");
}
} else { /* n is NOT constant, so laddered copy of 16x,8,4,2,1 */
__asm__ __volatile__(
" mov %0,%3 \n"
" lsr.f lp_count, %3,4 \n" /* 16x bytes */
" lpnz 3f \n"
"1: ld.ab %5, [%2, 4] \n"
"11: ld.ab %6, [%2, 4] \n"
"12: ld.ab %7, [%2, 4] \n"
"13: ld.ab %8, [%2, 4] \n"
" st.ab %5, [%1, 4] \n"
" st.ab %6, [%1, 4] \n"
" st.ab %7, [%1, 4] \n"
" st.ab %8, [%1, 4] \n"
" sub %0,%0,16 \n"
"3: and.f %3,%3,0xf \n" /* stragglers */
" bz 34f \n"
" bbit0 %3,3,31f \n" /* 8 bytes left */
"14: ld.ab %5, [%2,4] \n"
"15: ld.ab %6, [%2,4] \n"
" st.ab %5, [%1,4] \n"
" st.ab %6, [%1,4] \n"
" sub.f %0,%0,8 \n"
"31: bbit0 %3,2,32f \n" /* 4 bytes left */
"16: ld.ab %5, [%2,4] \n"
" st.ab %5, [%1,4] \n"
" sub.f %0,%0,4 \n"
"32: bbit0 %3,1,33f \n" /* 2 bytes left */
"17: ldw.ab %5, [%2,2] \n"
" stw.ab %5, [%1,2] \n"
" sub.f %0,%0,2 \n"
"33: bbit0 %3,0,34f \n"
"18: ldb.ab %5, [%2,1] \n" /* 1 byte left */
" stb.ab %5, [%1,1] \n"
" sub.f %0,%0,1 \n"
"34: ;nop \n"
" .section .fixup, \"ax\" \n"
" .align 4 \n"
"4: j 34b \n"
" .previous \n"
" .section __ex_table, \"a\" \n"
" .align 4 \n"
" .word 1b, 4b \n"
" .word 11b,4b \n"
" .word 12b,4b \n"
" .word 13b,4b \n"
" .word 14b,4b \n"
" .word 15b,4b \n"
" .word 16b,4b \n"
" .word 17b,4b \n"
" .word 18b,4b \n"
" .previous \n"
: "=r" (res), "+r"(to), "+r"(from), "+r"(n), "=r"(val),
"=r"(tmp1), "=r"(tmp2), "=r"(tmp3), "=r"(tmp4)
:
: "lp_count", "memory");
}
return res;
}
static inline unsigned long
raw_copy_to_user(void __user *to, const void *from, unsigned long n)
{
long res = 0;
char val;
unsigned long tmp1, tmp2, tmp3, tmp4;
unsigned long orig_n = n;
if (n == 0)
return 0;
/* unaligned */
if (((unsigned long)to & 0x3) || ((unsigned long)from & 0x3)) {
unsigned char tmp;
__asm__ __volatile__(
" mov.f lp_count, %0 \n"
" lpnz 3f \n"
" ldb.ab %1, [%3, 1] \n"
"1: stb.ab %1, [%2, 1] \n"
" sub %0, %0, 1 \n"
"3: ;nop \n"
" .section .fixup, \"ax\" \n"
" .align 4 \n"
"4: j 3b \n"
" .previous \n"
" .section __ex_table, \"a\" \n"
" .align 4 \n"
" .word 1b, 4b \n"
" .previous \n"
: "+r" (n),
/* Note as an '&' earlyclobber operand to make sure the
* temporary register inside the loop is not the same as
* FROM or TO.
*/
"=&r" (tmp), "+r" (to), "+r" (from)
:
: "lp_count", "memory");
return n;
}
if (__builtin_constant_p(orig_n)) {
res = orig_n;
if (orig_n / 16) {
orig_n = orig_n % 16;
__asm__ __volatile__(
" lsr lp_count, %7,4 \n"
" lp 3f \n"
" ld.ab %3, [%2, 4] \n"
" ld.ab %4, [%2, 4] \n"
" ld.ab %5, [%2, 4] \n"
" ld.ab %6, [%2, 4] \n"
"1: st.ab %3, [%1, 4] \n"
"11: st.ab %4, [%1, 4] \n"
"12: st.ab %5, [%1, 4] \n"
"13: st.ab %6, [%1, 4] \n"
" sub %0, %0, 16 \n"
"3:;nop \n"
" .section .fixup, \"ax\" \n"
" .align 4 \n"
"4: j 3b \n"
" .previous \n"
" .section __ex_table, \"a\" \n"
" .align 4 \n"
" .word 1b, 4b \n"
" .word 11b,4b \n"
" .word 12b,4b \n"
" .word 13b,4b \n"
" .previous \n"
: "+r" (res), "+r"(to), "+r"(from),
"=r"(tmp1), "=r"(tmp2), "=r"(tmp3), "=r"(tmp4)
: "ir"(n)
: "lp_count", "memory");
}
if (orig_n / 8) {
orig_n = orig_n % 8;
__asm__ __volatile__(
" ld.ab %3, [%2,4] \n"
" ld.ab %4, [%2,4] \n"
"14: st.ab %3, [%1,4] \n"
"15: st.ab %4, [%1,4] \n"
" sub %0, %0, 8 \n"
"31:;nop \n"
" .section .fixup, \"ax\" \n"
" .align 4 \n"
"4: j 31b \n"
" .previous \n"
" .section __ex_table, \"a\" \n"
" .align 4 \n"
" .word 14b,4b \n"
" .word 15b,4b \n"
" .previous \n"
: "+r" (res), "+r"(to), "+r"(from),
"=r"(tmp1), "=r"(tmp2)
:
: "memory");
}
if (orig_n / 4) {
orig_n = orig_n % 4;
__asm__ __volatile__(
" ld.ab %3, [%2,4] \n"
"16: st.ab %3, [%1,4] \n"
" sub %0, %0, 4 \n"
"32:;nop \n"
" .section .fixup, \"ax\" \n"
" .align 4 \n"
"4: j 32b \n"
" .previous \n"
" .section __ex_table, \"a\" \n"
" .align 4 \n"
" .word 16b,4b \n"
" .previous \n"
: "+r" (res), "+r"(to), "+r"(from), "=r"(tmp1)
:
: "memory");
}
if (orig_n / 2) {
orig_n = orig_n % 2;
__asm__ __volatile__(
" ldw.ab %3, [%2,2] \n"
"17: stw.ab %3, [%1,2] \n"
" sub %0, %0, 2 \n"
"33:;nop \n"
" .section .fixup, \"ax\" \n"
" .align 4 \n"
"4: j 33b \n"
" .previous \n"
" .section __ex_table, \"a\" \n"
" .align 4 \n"
" .word 17b,4b \n"
" .previous \n"
: "+r" (res), "+r"(to), "+r"(from), "=r"(tmp1)
:
: "memory");
}
if (orig_n & 1) {
__asm__ __volatile__(
" ldb.ab %3, [%2,1] \n"
"18: stb.ab %3, [%1,1] \n"
" sub %0, %0, 1 \n"
"34: ;nop \n"
" .section .fixup, \"ax\" \n"
" .align 4 \n"
"4: j 34b \n"
" .previous \n"
" .section __ex_table, \"a\" \n"
" .align 4 \n"
" .word 18b,4b \n"
" .previous \n"
: "+r" (res), "+r"(to), "+r"(from), "=r"(tmp1)
:
: "memory");
}
} else { /* n is NOT constant, so laddered copy of 16x,8,4,2,1 */
__asm__ __volatile__(
" mov %0,%3 \n"
" lsr.f lp_count, %3,4 \n" /* 16x bytes */
" lpnz 3f \n"
" ld.ab %5, [%2, 4] \n"
" ld.ab %6, [%2, 4] \n"
" ld.ab %7, [%2, 4] \n"
" ld.ab %8, [%2, 4] \n"
"1: st.ab %5, [%1, 4] \n"
"11: st.ab %6, [%1, 4] \n"
"12: st.ab %7, [%1, 4] \n"
"13: st.ab %8, [%1, 4] \n"
" sub %0, %0, 16 \n"
"3: and.f %3,%3,0xf \n" /* stragglers */
" bz 34f \n"
" bbit0 %3,3,31f \n" /* 8 bytes left */
" ld.ab %5, [%2,4] \n"
" ld.ab %6, [%2,4] \n"
"14: st.ab %5, [%1,4] \n"
"15: st.ab %6, [%1,4] \n"
" sub.f %0, %0, 8 \n"
"31: bbit0 %3,2,32f \n" /* 4 bytes left */
" ld.ab %5, [%2,4] \n"
"16: st.ab %5, [%1,4] \n"
" sub.f %0, %0, 4 \n"
"32: bbit0 %3,1,33f \n" /* 2 bytes left */
" ldw.ab %5, [%2,2] \n"
"17: stw.ab %5, [%1,2] \n"
" sub.f %0, %0, 2 \n"
"33: bbit0 %3,0,34f \n"
" ldb.ab %5, [%2,1] \n" /* 1 byte left */
"18: stb.ab %5, [%1,1] \n"
" sub.f %0, %0, 1 \n"
"34: ;nop \n"
" .section .fixup, \"ax\" \n"
" .align 4 \n"
"4: j 34b \n"
" .previous \n"
" .section __ex_table, \"a\" \n"
" .align 4 \n"
" .word 1b, 4b \n"
" .word 11b,4b \n"
" .word 12b,4b \n"
" .word 13b,4b \n"
" .word 14b,4b \n"
" .word 15b,4b \n"
" .word 16b,4b \n"
" .word 17b,4b \n"
" .word 18b,4b \n"
" .previous \n"
: "=r" (res), "+r"(to), "+r"(from), "+r"(n), "=r"(val),
"=r"(tmp1), "=r"(tmp2), "=r"(tmp3), "=r"(tmp4)
:
: "lp_count", "memory");
}
return res;
}
static inline unsigned long __arc_clear_user(void __user *to, unsigned long n)
{
long res = n;
unsigned char *d_char = to;
__asm__ __volatile__(
" bbit0 %0, 0, 1f \n"
"75: stb.ab %2, [%0,1] \n"
" sub %1, %1, 1 \n"
"1: bbit0 %0, 1, 2f \n"
"76: stw.ab %2, [%0,2] \n"
" sub %1, %1, 2 \n"
"2: asr.f lp_count, %1, 2 \n"
" lpnz 3f \n"
"77: st.ab %2, [%0,4] \n"
" sub %1, %1, 4 \n"
"3: bbit0 %1, 1, 4f \n"
"78: stw.ab %2, [%0,2] \n"
" sub %1, %1, 2 \n"
"4: bbit0 %1, 0, 5f \n"
"79: stb.ab %2, [%0,1] \n"
" sub %1, %1, 1 \n"
"5: \n"
" .section .fixup, \"ax\" \n"
" .align 4 \n"
"3: j 5b \n"
" .previous \n"
" .section __ex_table, \"a\" \n"
" .align 4 \n"
" .word 75b, 3b \n"
" .word 76b, 3b \n"
" .word 77b, 3b \n"
" .word 78b, 3b \n"
" .word 79b, 3b \n"
" .previous \n"
: "+r"(d_char), "+r"(res)
: "i"(0)
: "lp_count", "memory");
return res;
}
static inline long
__arc_strncpy_from_user(char *dst, const char __user *src, long count)
{
long res = 0;
char val;
if (count == 0)
return 0;
__asm__ __volatile__(
" mov lp_count, %5 \n"
" lp 3f \n"
"1: ldb.ab %3, [%2, 1] \n"
" breq.d %3, 0, 3f \n"
" stb.ab %3, [%1, 1] \n"
" add %0, %0, 1 # Num of NON NULL bytes copied \n"
"3: \n"
" .section .fixup, \"ax\" \n"
" .align 4 \n"
"4: mov %0, %4 # sets @res as -EFAULT \n"
" j 3b \n"
" .previous \n"
" .section __ex_table, \"a\" \n"
" .align 4 \n"
" .word 1b, 4b \n"
" .previous \n"
: "+r"(res), "+r"(dst), "+r"(src), "=r"(val)
: "g"(-EFAULT), "r"(count)
: "lp_count", "memory");
return res;
}
static inline long __arc_strnlen_user(const char __user *s, long n)
{
long res, tmp1, cnt;
char val;
__asm__ __volatile__(
" mov %2, %1 \n"
"1: ldb.ab %3, [%0, 1] \n"
" breq.d %3, 0, 2f \n"
" sub.f %2, %2, 1 \n"
" bnz 1b \n"
" sub %2, %2, 1 \n"
"2: sub %0, %1, %2 \n"
"3: ;nop \n"
" .section .fixup, \"ax\" \n"
" .align 4 \n"
"4: mov %0, 0 \n"
" j 3b \n"
" .previous \n"
" .section __ex_table, \"a\" \n"
" .align 4 \n"
" .word 1b, 4b \n"
" .previous \n"
: "=r"(res), "=r"(tmp1), "=r"(cnt), "=r"(val)
: "0"(s), "1"(n)
: "memory");
return res;
}
#ifndef CONFIG_CC_OPTIMIZE_FOR_SIZE
#define INLINE_COPY_TO_USER
#define INLINE_COPY_FROM_USER
#define __clear_user(d, n) __arc_clear_user(d, n)
#define __strncpy_from_user(d, s, n) __arc_strncpy_from_user(d, s, n)
#define __strnlen_user(s, n) __arc_strnlen_user(s, n)
#else
extern unsigned long arc_clear_user_noinline(void __user *to,
unsigned long n);
extern long arc_strncpy_from_user_noinline (char *dst, const char __user *src,
long count);
extern long arc_strnlen_user_noinline(const char __user *src, long n);
#define __clear_user(d, n) arc_clear_user_noinline(d, n)
#define __strncpy_from_user(d, s, n) arc_strncpy_from_user_noinline(d, s, n)
#define __strnlen_user(s, n) arc_strnlen_user_noinline(s, n)
#endif
#include <asm/segment.h>
#include <asm-generic/uaccess.h>
#endif
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