xref: /netbsd/sys/compat/linux/common/linux_llseek.c (revision f036aca9)
1 /*	$NetBSD: linux_llseek.c,v 1.35 2021/09/23 06:56:27 ryo Exp $	*/
2 
3 /*-
4  * Copyright (c) 1995, 1998 The NetBSD Foundation, Inc.
5  * All rights reserved.
6  *
7  * This code is derived from software contributed to The NetBSD Foundation
8  * by Frank van der Linden and Eric Haszlakiewicz.
9  *
10  * Redistribution and use in source and binary forms, with or without
11  * modification, are permitted provided that the following conditions
12  * are met:
13  * 1. Redistributions of source code must retain the above copyright
14  *    notice, this list of conditions and the following disclaimer.
15  * 2. Redistributions in binary form must reproduce the above copyright
16  *    notice, this list of conditions and the following disclaimer in the
17  *    documentation and/or other materials provided with the distribution.
18  *
19  * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
20  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
21  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
22  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
23  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
24  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
25  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
26  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
27  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
28  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
29  * POSSIBILITY OF SUCH DAMAGE.
30  */
31 
32 #include <sys/cdefs.h>
33 __KERNEL_RCSID(0, "$NetBSD: linux_llseek.c,v 1.35 2021/09/23 06:56:27 ryo Exp $");
34 
35 #include <sys/param.h>
36 #include <sys/systm.h>
37 #include <sys/kernel.h>
38 #include <sys/mount.h>
39 #include <sys/conf.h>
40 
41 #include <sys/sched.h>
42 #include <sys/syscallargs.h>
43 
44 #include <compat/linux/common/linux_types.h>
45 #include <compat/linux/common/linux_signal.h>
46 #include <compat/linux/common/linux_fcntl.h>
47 #include <compat/linux/common/linux_util.h>
48 
49 #include <compat/linux/linux_syscallargs.h>
50 
51 /* Used on: arm, i386, m68k, mips, ppc, sparc */
52 /* Not used on: aarch64, alpha, sparc64 */
53 
54 /*
55  * This appears to be part of a Linux attempt to switch to 64 bits file sizes.
56  */
57 int
linux_sys_llseek(struct lwp * l,const struct linux_sys_llseek_args * uap,register_t * retval)58 linux_sys_llseek(struct lwp *l, const struct linux_sys_llseek_args *uap, register_t *retval)
59 {
60 	/* {
61 		syscallarg(int) fd;
62 		syscallarg(uint32_t) ohigh;
63 		syscallarg(uint32_t) olow;
64 		syscallarg(void *) res;
65 		syscallarg(int) whence;
66 	} */
67 	struct sys_lseek_args bla;
68 	int error;
69 	off_t off;
70 
71 	off = SCARG(uap, olow) | (((off_t) SCARG(uap, ohigh)) << 32);
72 
73 	SCARG(&bla, fd) = SCARG(uap, fd);
74 	SCARG(&bla, offset) = off;
75 	SCARG(&bla, whence) = SCARG(uap, whence);
76 
77 	if ((error = sys_lseek(l, &bla, retval)))
78 		return error;
79 
80 	if ((error = copyout(retval, SCARG(uap, res), sizeof (off_t))))
81 		return error;
82 
83 	retval[0] = 0;
84 	return 0;
85 }
86