original_kernel/arch/riscv/lib/riscv_v_helpers.c

46 lines
977 B
C

// SPDX-License-Identifier: GPL-2.0-or-later
/*
* Copyright (C) 2023 SiFive
* Author: Andy Chiu <andy.chiu@sifive.com>
*/
#include <linux/linkage.h>
#include <asm/asm.h>
#include <asm/vector.h>
#include <asm/simd.h>
#ifdef CONFIG_MMU
#include <asm/asm-prototypes.h>
#endif
#ifdef CONFIG_MMU
size_t riscv_v_usercopy_threshold = CONFIG_RISCV_ISA_V_UCOPY_THRESHOLD;
int __asm_vector_usercopy(void *dst, void *src, size_t n);
int fallback_scalar_usercopy(void *dst, void *src, size_t n);
asmlinkage int enter_vector_usercopy(void *dst, void *src, size_t n)
{
size_t remain, copied;
/* skip has_vector() check because it has been done by the asm */
if (!may_use_simd())
goto fallback;
kernel_vector_begin();
remain = __asm_vector_usercopy(dst, src, n);
kernel_vector_end();
if (remain) {
copied = n - remain;
dst += copied;
src += copied;
n = remain;
goto fallback;
}
return remain;
fallback:
return fallback_scalar_usercopy(dst, src, n);
}
#endif