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 */
49 * Copies from a kernel to user address
51 * int copyout(const void *kaddr, void *udaddr, size_t len)
54 cbz x2, 2f /* If len == 0 then skip loop */
56 ldr x4, =VM_MAXUSER_ADDRESS
58 b.hi copyio_fault_nopcb
60 adr x6, copyio_fault /* Get the handler address */
61 SET_FAULT_HANDLER(x6, x7) /* Set the handler */
63 1: ldrb w4, [x0], #1 /* Load from kaddr */
64 strb w4, [x1], #1 /* Store in uaddr */
65 sub x2, x2, #1 /* len-- */
68 SET_FAULT_HANDLER(xzr, x7) /* Clear the handler */
70 2: mov x0, xzr /* return 0 */
75 * Copies from a user to kernel address
77 * int copyin(const void *uaddr, void *kdaddr, size_t len)
80 cbz x2, 2f /* If len == 0 then skip loop */
82 ldr x4, =VM_MAXUSER_ADDRESS
84 b.hi copyio_fault_nopcb
86 adr x6, copyio_fault /* Get the handler address */
87 SET_FAULT_HANDLER(x6, x7) /* Set the handler */
89 1: ldrb w4, [x0], #1 /* Load from uaddr */
90 strb w4, [x1], #1 /* Store in kaddr */
91 sub x2, x2, #1 /* len-- */
94 SET_FAULT_HANDLER(xzr, x7) /* Clear the handler */
96 2: mov x0, xzr /* return 0 */
101 * Copies a string from a user to kernel address
103 * int copyinstr(const void *udaddr, void *kaddr, size_t len, size_t *done)
106 mov x5, xzr /* count = 0 */
107 mov w4, #1 /* If zero return faulure */
108 cbz x2, 3f /* If len == 0 then skip loop */
109 ldr x7, =VM_MAXUSER_ADDRESS
111 adr x6, copyio_fault /* Get the handler address */
112 SET_FAULT_HANDLER(x6, x7) /* Set the handler */
116 ldrb w4, [x0], #1 /* Load from uaddr */
117 strb w4, [x1], #1 /* Store in kaddr */
118 add x5, x5, #1 /* count++ */
119 cbz w4, 2f /* Break when NUL-terminated */
120 sub x2, x2, #1 /* len-- */
123 2: SET_FAULT_HANDLER(xzr, x7) /* Clear the handler */
125 3: cbz x3, 4f /* Check if done != NULL */
126 str x5, [x3] /* done = count */
128 4: mov w1, #ENAMETOOLONG /* Load ENAMETOOLONG to return if failed */
129 cmp w4, #0 /* Check if we saved the NUL-terminator */
130 csel w0, wzr, w1, eq /* If so return success, else failure */