xref: /freebsd/sys/compat/linux/linux_rseq.c (revision 2008043f386721d58158e37e0d7e50df8095942d)
1 /*-
2  * SPDX-License-Identifier: BSD-2-Clause
3  *
4  * Copyright (c) 2022 Dmitry Chagin <dchagin@FreeBSD.org>
5  *
6  * Redistribution and use in source and binary forms, with or without
7  * modification, are permitted provided that the following conditions
8  * are met:
9  * 1. Redistributions of source code must retain the above copyright
10  *    notice, this list of conditions and the following disclaimer.
11  * 2. Redistributions in binary form must reproduce the above copyright
12  *    notice, this list of conditions and the following disclaimer in the
13  *    documentation and/or other materials provided with the distribution.
14  *
15  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
16  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
17  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
18  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
19  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
20  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
21  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
22  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
23  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
24  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
25  * SUCH DAMAGE.
26  */
27 
28 #include <sys/param.h>
29 #include <sys/systm.h>
30 
31 #ifdef COMPAT_LINUX32
32 #include <machine/../linux32/linux.h>
33 #include <machine/../linux32/linux32_proto.h>
34 #else
35 #include <machine/../linux/linux.h>
36 #include <machine/../linux/linux_proto.h>
37 #endif
38 
39 
40 enum linux_rseq_cpu_id_state {
41 	LINUX_RSEQ_CPU_ID_UNINITIALIZED			= -1,
42 	LINUX_RSEQ_CPU_ID_REGISTRATION_FAILED		= -2,
43 };
44 
45 enum linux_rseq_flags {
46 	LINUX_RSEQ_FLAG_UNREGISTER			= (1 << 0),
47 };
48 
49 enum linux_rseq_cs_flags_bit {
50 	LINUX_RSEQ_CS_FLAG_NO_RESTART_ON_PREEMPT_BIT	= 0,
51 	LINUX_RSEQ_CS_FLAG_NO_RESTART_ON_SIGNAL_BIT	= 1,
52 	LINUX_RSEQ_CS_FLAG_NO_RESTART_ON_MIGRATE_BIT	= 2,
53 };
54 
55 enum linux_rseq_cs_flags {
56 	LINUX_RSEQ_CS_FLAG_NO_RESTART_ON_PREEMPT	=
57 		(1U << LINUX_RSEQ_CS_FLAG_NO_RESTART_ON_PREEMPT_BIT),
58 	LINUX_RSEQ_CS_FLAG_NO_RESTART_ON_SIGNAL	=
59 		(1U << LINUX_RSEQ_CS_FLAG_NO_RESTART_ON_SIGNAL_BIT),
60 	LINUX_RSEQ_CS_FLAG_NO_RESTART_ON_MIGRATE	=
61 		(1U << LINUX_RSEQ_CS_FLAG_NO_RESTART_ON_MIGRATE_BIT),
62 };
63 
64 struct linux_rseq_cs {
65 	uint32_t version;
66 	uint32_t flags;
67 	uint64_t start_ip;
68 	uint64_t post_commit_offset;
69 	uint64_t abort_ip;
70 } __attribute__((aligned(4 * sizeof(uint64_t))));
71 
72 struct linux_rseq {
73 	uint32_t cpu_id_start;
74 	uint32_t cpu_id;
75 	uint64_t rseq_cs;
76 	uint32_t flags;
77 } __attribute__((aligned(4 * sizeof(uint64_t))));
78 
79 int
80 linux_rseq(struct thread *td, struct linux_rseq_args *args)
81 {
82 
83 	return (ENOSYS);
84 }
85