diff options
Diffstat (limited to 'arch/riscv/lib/uaccess_vector.S')
-rw-r--r-- | arch/riscv/lib/uaccess_vector.S | 53 |
1 files changed, 53 insertions, 0 deletions
diff --git a/arch/riscv/lib/uaccess_vector.S b/arch/riscv/lib/uaccess_vector.S new file mode 100644 index 0000000000..51ab5588e9 --- /dev/null +++ b/arch/riscv/lib/uaccess_vector.S @@ -0,0 +1,53 @@ +/* SPDX-License-Identifier: GPL-2.0-only */ + +#include <linux/linkage.h> +#include <asm-generic/export.h> +#include <asm/asm.h> +#include <asm/asm-extable.h> +#include <asm/csr.h> + +#define pDst a0 +#define pSrc a1 +#define iNum a2 + +#define iVL a3 + +#define ELEM_LMUL_SETTING m8 +#define vData v0 + + .macro fixup op reg addr lbl +100: + \op \reg, \addr + _asm_extable 100b, \lbl + .endm + +SYM_FUNC_START(__asm_vector_usercopy) + /* Enable access to user memory */ + li t6, SR_SUM + csrs CSR_STATUS, t6 + +loop: + vsetvli iVL, iNum, e8, ELEM_LMUL_SETTING, ta, ma + fixup vle8.v vData, (pSrc), 10f + sub iNum, iNum, iVL + add pSrc, pSrc, iVL + fixup vse8.v vData, (pDst), 11f + add pDst, pDst, iVL + bnez iNum, loop + + /* Exception fixup for vector load is shared with normal exit */ +10: + /* Disable access to user memory */ + csrc CSR_STATUS, t6 + mv a0, iNum + ret + + /* Exception fixup code for vector store. */ +11: + /* Undo the subtraction after vle8.v */ + add iNum, iNum, iVL + /* Make sure the scalar fallback skip already processed bytes */ + csrr t2, CSR_VSTART + sub iNum, iNum, t2 + j 10b +SYM_FUNC_END(__asm_vector_usercopy) |