1/*-
2 * SPDX-License-Identifier: BSD-3-Clause
3 *
4 * Copyright (c) 1994 Christos Zoulas
5 * Copyright (c) 1995 Frank van der Linden
6 * Copyright (c) 1995 Scott Bartram
7 * All rights reserved.
8 *
9 * Redistribution and use in source and binary forms, with or without
10 * modification, are permitted provided that the following conditions
11 * are met:
12 * 1. Redistributions of source code must retain the above copyright
13 *    notice, this list of conditions and the following disclaimer.
14 * 2. Redistributions in binary form must reproduce the above copyright
15 *    notice, this list of conditions and the following disclaimer in the
16 *    documentation and/or other materials provided with the distribution.
17 * 3. The name of the author may not be used to endorse or promote products
18 *    derived from this software without specific prior written permission
19 *
20 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
21 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
22 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
23 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
24 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
25 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
26 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
27 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
28 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
29 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
30 *
31 *	from: svr4_util.c,v 1.5 1995/01/22 23:44:50 christos Exp
32 */
33
34#include <sys/cdefs.h>
35__FBSDID("$FreeBSD$");
36
37#include <sys/param.h>
38#include <sys/bus.h>
39#include <sys/fcntl.h>
40#include <sys/lock.h>
41#include <sys/malloc.h>
42#include <sys/kernel.h>
43#include <sys/linker_set.h>
44#include <sys/mutex.h>
45#include <sys/namei.h>
46#include <sys/proc.h>
47#include <sys/sdt.h>
48#include <sys/syscallsubr.h>
49#include <sys/sysctl.h>
50#include <sys/systm.h>
51#include <sys/vnode.h>
52
53#include <machine/stdarg.h>
54
55#include <compat/linux/linux_dtrace.h>
56#include <compat/linux/linux_mib.h>
57#include <compat/linux/linux_util.h>
58
59MALLOC_DEFINE(M_LINUX, "linux", "Linux mode structures");
60MALLOC_DEFINE(M_EPOLL, "lepoll", "Linux events structures");
61MALLOC_DEFINE(M_FUTEX, "futex", "Linux futexes");
62MALLOC_DEFINE(M_FUTEX_WP, "futex wp", "Linux futex waiting proc");
63
64FEATURE(linuxulator_v4l, "V4L ioctl wrapper support in the linuxulator");
65FEATURE(linuxulator_v4l2, "V4L2 ioctl wrapper support in the linuxulator");
66
67/**
68 * Special DTrace provider for the linuxulator.
69 *
70 * In this file we define the provider for the entire linuxulator. All
71 * modules (= files of the linuxulator) use it.
72 *
73 * We define a different name depending on the emulated bitsize, see
74 * ../../<ARCH>/linux{,32}/linux.h, e.g.:
75 *      native bitsize          = linuxulator
76 *      amd64, 32bit emulation  = linuxulator32
77 */
78LIN_SDT_PROVIDER_DEFINE(linuxulator);
79LIN_SDT_PROVIDER_DEFINE(linuxulator32);
80
81char linux_emul_path[MAXPATHLEN] = "/compat/linux";
82
83SYSCTL_STRING(_compat_linux, OID_AUTO, emul_path, CTLFLAG_RWTUN,
84    linux_emul_path, sizeof(linux_emul_path),
85    "Linux runtime environment path");
86
87/*
88 * Search an alternate path before passing pathname arguments on to
89 * system calls. Useful for keeping a separate 'emulation tree'.
90 *
91 * If cflag is set, we check if an attempt can be made to create the
92 * named file, i.e. we check if the directory it should be in exists.
93 */
94int
95linux_emul_convpath(struct thread *td, const char *path, enum uio_seg pathseg,
96    char **pbuf, int cflag, int dfd)
97{
98	int retval;
99
100	retval = kern_alternate_path(td, linux_emul_path, path, pathseg, pbuf,
101	    cflag, dfd);
102
103	return (retval);
104}
105
106void
107linux_msg(const struct thread *td, const char *fmt, ...)
108{
109	va_list ap;
110	struct proc *p;
111
112	if (linux_debug == 0)
113		return;
114
115	p = td->td_proc;
116	printf("linux: pid %d (%s): ", (int)p->p_pid, p->p_comm);
117	va_start(ap, fmt);
118	vprintf(fmt, ap);
119	va_end(ap);
120	printf("\n");
121}
122
123struct device_element
124{
125	TAILQ_ENTRY(device_element) list;
126	struct linux_device_handler entry;
127};
128
129static TAILQ_HEAD(, device_element) devices =
130	TAILQ_HEAD_INITIALIZER(devices);
131
132static struct linux_device_handler null_handler =
133	{ "mem", "mem", "null", "null", 1, 3, 1};
134
135DATA_SET(linux_device_handler_set, null_handler);
136
137char *
138linux_driver_get_name_dev(device_t dev)
139{
140	struct device_element *de;
141	const char *device_name = device_get_name(dev);
142
143	if (device_name == NULL)
144		return (NULL);
145	TAILQ_FOREACH(de, &devices, list) {
146		if (strcmp(device_name, de->entry.bsd_driver_name) == 0)
147			return (de->entry.linux_driver_name);
148	}
149
150	return (NULL);
151}
152
153int
154linux_driver_get_major_minor(const char *node, int *major, int *minor)
155{
156	struct device_element *de;
157	unsigned long devno;
158	size_t sz;
159
160	if (node == NULL || major == NULL || minor == NULL)
161		return (1);
162
163	sz = sizeof("pts/") - 1;
164	if (strncmp(node, "pts/", sz) == 0 && node[sz] != '\0') {
165		/*
166		 * Linux checks major and minors of the slave device
167		 * to make sure it's a pty device, so let's make him
168		 * believe it is.
169		 */
170		devno = strtoul(node + sz, NULL, 10);
171		*major = 136 + (devno / 256);
172		*minor = devno % 256;
173		return (0);
174	}
175
176	sz = sizeof("dri/card") - 1;
177	if (strncmp(node, "dri/card", sz) == 0 && node[sz] != '\0') {
178		devno = strtoul(node + sz, NULL, 10);
179		*major = 226 + (devno / 256);
180		*minor = devno % 256;
181		return (0);
182	}
183	sz = sizeof("dri/controlD") - 1;
184	if (strncmp(node, "dri/controlD", sz) == 0 && node[sz] != '\0') {
185		devno = strtoul(node + sz, NULL, 10);
186		*major = 226 + (devno / 256);
187		*minor = devno % 256;
188		return (0);
189	}
190	sz = sizeof("dri/renderD") - 1;
191	if (strncmp(node, "dri/renderD", sz) == 0 && node[sz] != '\0') {
192		devno = strtoul(node + sz, NULL, 10);
193		*major = 226 + (devno / 256);
194		*minor = devno % 256;
195		return (0);
196	}
197	sz = sizeof("drm/") - 1;
198	if (strncmp(node, "drm/", sz) == 0 && node[sz] != '\0') {
199		devno = strtoul(node + sz, NULL, 10);
200		*major = 226 + (devno / 256);
201		*minor = devno % 256;
202		return (0);
203	}
204
205	TAILQ_FOREACH(de, &devices, list) {
206		if (strcmp(node, de->entry.bsd_device_name) == 0) {
207			*major = de->entry.linux_major;
208			*minor = de->entry.linux_minor;
209			return (0);
210		}
211	}
212
213	return (1);
214}
215
216char *
217linux_get_char_devices()
218{
219	struct device_element *de;
220	char *temp, *string, *last;
221	char formated[256];
222	int current_size = 0, string_size = 1024;
223
224	string = malloc(string_size, M_LINUX, M_WAITOK);
225	string[0] = '\000';
226	last = "";
227	TAILQ_FOREACH(de, &devices, list) {
228		if (!de->entry.linux_char_device)
229			continue;
230		temp = string;
231		if (strcmp(last, de->entry.bsd_driver_name) != 0) {
232			last = de->entry.bsd_driver_name;
233
234			snprintf(formated, sizeof(formated), "%3d %s\n",
235				 de->entry.linux_major,
236				 de->entry.linux_device_name);
237			if (strlen(formated) + current_size
238			    >= string_size) {
239				string_size *= 2;
240				string = malloc(string_size,
241				    M_LINUX, M_WAITOK);
242				bcopy(temp, string, current_size);
243				free(temp, M_LINUX);
244			}
245			strcat(string, formated);
246			current_size = strlen(string);
247		}
248	}
249
250	return (string);
251}
252
253void
254linux_free_get_char_devices(char *string)
255{
256
257	free(string, M_LINUX);
258}
259
260static int linux_major_starting = 200;
261
262int
263linux_device_register_handler(struct linux_device_handler *d)
264{
265	struct device_element *de;
266
267	if (d == NULL)
268		return (EINVAL);
269
270	de = malloc(sizeof(*de), M_LINUX, M_WAITOK);
271	if (d->linux_major < 0) {
272		d->linux_major = linux_major_starting++;
273	}
274	bcopy(d, &de->entry, sizeof(*d));
275
276	/* Add the element to the list, sorted on span. */
277	TAILQ_INSERT_TAIL(&devices, de, list);
278
279	return (0);
280}
281
282int
283linux_device_unregister_handler(struct linux_device_handler *d)
284{
285	struct device_element *de;
286
287	if (d == NULL)
288		return (EINVAL);
289
290	TAILQ_FOREACH(de, &devices, list) {
291		if (bcmp(d, &de->entry, sizeof(*d)) == 0) {
292			TAILQ_REMOVE(&devices, de, list);
293			free(de, M_LINUX);
294
295			return (0);
296		}
297	}
298
299	return (EINVAL);
300}
301