2 * Copyright (c) 2015 The FreeBSD Foundation
5 * This software was developed by Andrew Turner under
6 * sponsorship from the FreeBSD Foundation.
8 * Redistribution and use in source and binary forms, with or without
9 * modification, are permitted provided that the following conditions
11 * 1. Redistributions of source code must retain the above copyright
12 * notice, this list of conditions and the following disclaimer.
13 * 2. Redistributions in binary form must reproduce the above copyright
14 * notice, this list of conditions and the following disclaimer in the
15 * documentation and/or other materials provided with the distribution.
17 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
18 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
19 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
20 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
21 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
22 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
23 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
24 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
25 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
26 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
31 #include <machine/asm.h>
32 __FBSDID("$FreeBSD$");
34 #include <sys/errno.h>
39 * Fault handler for the copy{in,out} functions below.
42 SET_FAULT_HANDLER(xzr, x1) /* Clear the handler */
48 * Copies from a kernel to user address
50 * int copyout(const void *kaddr, void *udaddr, size_t len)
53 cbz x2, 2f /* If len == 0 then skip loop */
55 adr x6, copyio_fault /* Get the handler address */
56 SET_FAULT_HANDLER(x6, x7) /* Set the handler */
58 1: ldrb w4, [x0], #1 /* Load from kaddr */
59 strb w4, [x1], #1 /* Store in uaddr */
60 sub x2, x2, #1 /* len-- */
63 SET_FAULT_HANDLER(xzr, x7) /* Clear the handler */
65 2: mov x0, xzr /* return 0 */
70 * Copies from a user to kernel address
72 * int copyin(const void *uaddr, void *kdaddr, size_t len)
75 cbz x2, 2f /* If len == 0 then skip loop */
77 adr x6, copyio_fault /* Get the handler address */
78 SET_FAULT_HANDLER(x6, x7) /* Set the handler */
80 1: ldrb w4, [x0], #1 /* Load from uaddr */
81 strb w4, [x1], #1 /* Store in kaddr */
82 sub x2, x2, #1 /* len-- */
85 SET_FAULT_HANDLER(xzr, x7) /* Clear the handler */
87 2: mov x0, xzr /* return 0 */
92 * Copies a string from a user to kernel address
94 * int copyinstr(const void *udaddr, void *kaddr, size_t len, size_t *done)
97 mov x5, xzr /* count = 0 */
98 cbz x2, 3f /* If len == 0 then skip loop */
100 adr x6, copyio_fault /* Get the handler address */
101 SET_FAULT_HANDLER(x6, x7) /* Set the handler */
103 1: ldrb w4, [x0], #1 /* Load from uaddr */
104 strb w4, [x1], #1 /* Store in kaddr */
105 cbz w4, 2f /* If == 0 then break */
106 sub x2, x2, #1 /* len-- */
107 add x5, x5, #1 /* count++ */
110 2: SET_FAULT_HANDLER(xzr, x7) /* Clear the handler */
112 3: cbz x3, 4f /* Check if done != NULL */
113 add x5, x5, #1 /* count++ */
114 str x5, [x3] /* done = count */
116 4: mov x0, xzr /* return 0 */