+++ /dev/null
-/* $OpenBSD: copyinout.S,v 1.2 2021/05/12 01:20:52 jsg Exp $ */
-
-/*-
- * Copyright (c) 2015-2018 Ruslan Bukin <br@bsdpad.com>
- * Copyright (c) 2019 Mitchell Horne
- * Copyright (c) 2020 Brian Bamsch <bbamsch@google.com>
- * All rights reserved.
- *
- * Portions of this software were developed by SRI International and the
- * University of Cambridge Computer Laboratory under DARPA/AFRL contract
- * FA8750-10-C-0237 ("CTSRD"), as part of the DARPA CRASH research programme.
- *
- * Portions of this software were developed by the University of Cambridge
- * Computer Laboratory as part of the CTSRD Project, with support from the
- * UK Higher Education Innovation Fund (HEIF).
- *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions
- * are met:
- * 1. Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- * 2. Redistributions in binary form must reproduce the above copyright
- * notice, this list of conditions and the following disclaimer in the
- * documentation and/or other materials provided with the distribution.
- *
- * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
- * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
- * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
- * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
- * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
- * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
- * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
- * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
- * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
- * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
- * SUCH DAMAGE.
- */
-
-#include "assym.h"
-#include <machine/asm.h>
-#include <machine/riscvreg.h>
-#include <sys/errno.h>
-
-/*
- * Fault handler for the copy{in,out} functions below.
- */
-ENTRY(copyio_fault)
- SET_FAULT_HANDLER(x0, a1) /* Clear the handler */
- EXIT_USER_ACCESS(a1)
-copyio_fault_nopcb:
- li a0, EFAULT
- RETGUARD_CHECK(copyio, t6)
- ret
-END(copyio_fault)
-
-/*
- * copycommon - common copy routine
- *
- * a0 - Source address
- * a1 - Destination address
- * a2 - Size of copy
- */
- .macro copycommon
- la a6, copyio_fault /* Get the handler address */
- SET_FAULT_HANDLER(a6, a7) /* Set the handler */
- ENTER_USER_ACCESS(a7)
-
- li t2, XLEN_BYTES
- blt a2, t2, 4f /* Byte-copy if len < XLEN_BYTES */
-
- /*
- * Compare lower bits of src and dest.
- * If they are aligned with each other, we can do word copy.
- */
- andi t0, a0, (XLEN_BYTES-1) /* Low bits of src */
- andi t1, a1, (XLEN_BYTES-1) /* Low bits of dest */
- bne t0, t1, 4f /* Misaligned. Go to byte copy */
- beqz t0, 2f /* Already word-aligned, skip ahead */
-
- /* Byte copy until the first word-aligned address */
-1: lb a4, 0(a0) /* Load byte from src */
- addi a0, a0, 1
- sb a4, 0(a1) /* Store byte in dest */
- addi a1, a1, 1
- addi a2, a2, -1 /* len-- */
- andi t0, a0, (XLEN_BYTES-1)
- bnez t0, 1b
- j 3f
-
- /* Copy words */
-2: ld a4, 0(a0) /* Load word from src */
- addi a0, a0, XLEN_BYTES
- sd a4, 0(a1) /* Store word in dest */
- addi a1, a1, XLEN_BYTES
- addi a2, a2, -XLEN_BYTES /* len -= XLEN_BYTES */
-3: bgeu a2, t2, 2b /* Again if len >= XLEN_BYTES */
-
- /* Check if we're finished */
- beqz a2, 5f
-
- /* Copy any remaining bytes */
-4: lb a4, 0(a0) /* Load byte from src */
- addi a0, a0, 1
- sb a4, 0(a1) /* Store byte in dest */
- addi a1, a1, 1
- addi a2, a2, -1 /* len-- */
- bnez a2, 4b
-
-5: EXIT_USER_ACCESS(a7)
- SET_FAULT_HANDLER(x0, a7) /* Clear the handler */
- .endm
-
-/*
- * Copies from a kernel to user address
- *
- * int copyout(const void *kaddr, void *udaddr, size_t len)
- */
-ENTRY(copyout)
- RETGUARD_SETUP(copyio, t6)
- beqz a2, copyout_end /* If len == 0 then skip loop */
- add a3, a1, a2
- li a4, VM_MAXUSER_ADDRESS
- bgt a3, a4, copyio_fault_nopcb
-
- copycommon
-
-copyout_end:
- li a0, 0 /* return 0 */
- RETGUARD_CHECK(copyio, t6)
- ret
-END(copyout)
-
-/*
- * Copies from a user to kernel address
- *
- * int copyin(const void *uaddr, void *kaddr, size_t len)
- */
-ENTRY(copyin)
- RETGUARD_SETUP(copyio, t6)
- beqz a2, copyin_end /* If len == 0 then skip loop */
- add a3, a0, a2
- li a4, VM_MAXUSER_ADDRESS
- bgt a3, a4, copyio_fault_nopcb
-
- copycommon
-
-copyin_end:
- li a0, 0 /* return 0 */
- RETGUARD_CHECK(copyio, t6)
- ret
-END(copyin)
-
-/*
- * Copies a string from a user to kernel address
- *
- * int copyinstr(const void *udaddr, void *kaddr, size_t len, size_t *done)
- */
-ENTRY(copyinstr)
- RETGUARD_SETUP(copyinstr, t6)
- mv a5, x0 /* count = 0 */
- beqz a2, 3f /* If len == 0 then skip loop */
-
- la a6, copyio_fault /* Get the handler address */
- SET_FAULT_HANDLER(a6, a7) /* Set the handler */
- ENTER_USER_ACCESS(a7)
-
- li a7, VM_MAXUSER_ADDRESS
-1: bgt a0, a7, copyio_fault
- lb a4, 0(a0) /* Load from uaddr */
- addi a0, a0, 1
- sb a4, 0(a1) /* Store in kaddr */
- addi a1, a1, 1
- beqz a4, 2f
- addi a2, a2, -1 /* len-- */
- addi a5, a5, 1 /* count++ */
- bnez a2, 1b
-
-2: EXIT_USER_ACCESS(a7)
- SET_FAULT_HANDLER(x0, a7) /* Clear the handler */
-
-3: beqz a3, 4f /* Check if done != NULL */
- addi a5, a5, 1 /* count++ */
- sd a5, 0(a3) /* done = count */
-
-4: mv a0, x0 /* return 0 */
- beqz a4, 5f
- li a0, ENAMETOOLONG
-
-5: RETGUARD_CHECK(copyinstr, t6)
- ret
-END(copyinstr)
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