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/conf.h>
40#include <sys/fcntl.h>
41#include <sys/jail.h>
42#include <sys/lock.h>
43#include <sys/malloc.h>
44#include <sys/kernel.h>
45#include <sys/linker_set.h>
46#include <sys/mutex.h>
47#include <sys/namei.h>
48#include <sys/proc.h>
49#include <sys/sdt.h>
50#include <sys/syscallsubr.h>
51#include <sys/sysctl.h>
52#include <sys/systm.h>
53#include <sys/vnode.h>
54
55#include <machine/stdarg.h>
56
57#include <compat/linux/linux_dtrace.h>
58#include <compat/linux/linux_mib.h>
59#include <compat/linux/linux_util.h>
60
61MALLOC_DEFINE(M_LINUX, "linux", "Linux mode structures");
62MALLOC_DEFINE(M_EPOLL, "lepoll", "Linux events structures");
63MALLOC_DEFINE(M_FUTEX, "futex", "Linux futexes");
64MALLOC_DEFINE(M_FUTEX_WP, "futex wp", "Linux futex waiting proc");
65
66FEATURE(linuxulator_v4l, "V4L ioctl wrapper support in the linuxulator");
67FEATURE(linuxulator_v4l2, "V4L2 ioctl wrapper support in the linuxulator");
68
69/**
70 * Special DTrace provider for the linuxulator.
71 *
72 * In this file we define the provider for the entire linuxulator. All
73 * modules (= files of the linuxulator) use it.
74 *
75 * We define a different name depending on the emulated bitsize, see
76 * ../../<ARCH>/linux{,32}/linux.h, e.g.:
77 *      native bitsize          = linuxulator
78 *      amd64, 32bit emulation  = linuxulator32
79 */
80LIN_SDT_PROVIDER_DEFINE(linuxulator);
81LIN_SDT_PROVIDER_DEFINE(linuxulator32);
82
83char linux_emul_path[MAXPATHLEN] = "/compat/linux";
84
85SYSCTL_STRING(_compat_linux, OID_AUTO, emul_path, CTLFLAG_RWTUN,
86    linux_emul_path, sizeof(linux_emul_path),
87    "Linux runtime environment path");
88
89/*
90 * Search an alternate path before passing pathname arguments on to
91 * system calls. Useful for keeping a separate 'emulation tree'.
92 *
93 * If cflag is set, we check if an attempt can be made to create the
94 * named file, i.e. we check if the directory it should be in exists.
95 */
96int
97linux_emul_convpath(struct thread *td, const char *path, enum uio_seg pathseg,
98    char **pbuf, int cflag, int dfd)
99{
100	int retval;
101
102	retval = kern_alternate_path(td, linux_emul_path, path, pathseg, pbuf,
103	    cflag, dfd);
104
105	return (retval);
106}
107
108void
109linux_msg(const struct thread *td, const char *fmt, ...)
110{
111	va_list ap;
112	struct proc *p;
113
114	if (linux_debug == 0)
115		return;
116
117	p = td->td_proc;
118	printf("linux: jid %d pid %d (%s): ", p->p_ucred->cr_prison->pr_id,
119	    (int)p->p_pid, p->p_comm);
120	va_start(ap, fmt);
121	vprintf(fmt, ap);
122	va_end(ap);
123	printf("\n");
124}
125
126struct device_element
127{
128	TAILQ_ENTRY(device_element) list;
129	struct linux_device_handler entry;
130};
131
132static TAILQ_HEAD(, device_element) devices =
133	TAILQ_HEAD_INITIALIZER(devices);
134
135static struct linux_device_handler null_handler =
136	{ "mem", "mem", "null", "null", 1, 3, 1};
137
138DATA_SET(linux_device_handler_set, null_handler);
139
140char *
141linux_driver_get_name_dev(device_t dev)
142{
143	struct device_element *de;
144	const char *device_name = device_get_name(dev);
145
146	if (device_name == NULL)
147		return (NULL);
148	TAILQ_FOREACH(de, &devices, list) {
149		if (strcmp(device_name, de->entry.bsd_driver_name) == 0)
150			return (de->entry.linux_driver_name);
151	}
152
153	return (NULL);
154}
155
156int
157linux_driver_get_major_minor(const char *node, int *major, int *minor)
158{
159	struct device_element *de;
160	unsigned long devno;
161	size_t sz;
162
163	if (node == NULL || major == NULL || minor == NULL)
164		return (1);
165
166	sz = sizeof("pts/") - 1;
167	if (strncmp(node, "pts/", sz) == 0 && node[sz] != '\0') {
168		/*
169		 * Linux checks major and minors of the slave device
170		 * to make sure it's a pty device, so let's make him
171		 * believe it is.
172		 */
173		devno = strtoul(node + sz, NULL, 10);
174		*major = 136 + (devno / 256);
175		*minor = devno % 256;
176		return (0);
177	}
178
179	sz = sizeof("dri/card") - 1;
180	if (strncmp(node, "dri/card", sz) == 0 && node[sz] != '\0') {
181		devno = strtoul(node + sz, NULL, 10);
182		*major = 226 + (devno / 256);
183		*minor = devno % 256;
184		return (0);
185	}
186	sz = sizeof("dri/controlD") - 1;
187	if (strncmp(node, "dri/controlD", sz) == 0 && node[sz] != '\0') {
188		devno = strtoul(node + sz, NULL, 10);
189		*major = 226 + (devno / 256);
190		*minor = devno % 256;
191		return (0);
192	}
193	sz = sizeof("dri/renderD") - 1;
194	if (strncmp(node, "dri/renderD", sz) == 0 && node[sz] != '\0') {
195		devno = strtoul(node + sz, NULL, 10);
196		*major = 226 + (devno / 256);
197		*minor = devno % 256;
198		return (0);
199	}
200	sz = sizeof("drm/") - 1;
201	if (strncmp(node, "drm/", sz) == 0 && node[sz] != '\0') {
202		devno = strtoul(node + sz, NULL, 10);
203		*major = 226 + (devno / 256);
204		*minor = devno % 256;
205		return (0);
206	}
207
208	TAILQ_FOREACH(de, &devices, list) {
209		if (strcmp(node, de->entry.bsd_device_name) == 0) {
210			*major = de->entry.linux_major;
211			*minor = de->entry.linux_minor;
212			return (0);
213		}
214	}
215
216	return (1);
217}
218
219int
220linux_vn_get_major_minor(const struct vnode *vp, int *major, int *minor)
221{
222	int error;
223
224	if (vp->v_type != VCHR)
225		return (ENOTBLK);
226	dev_lock();
227	if (vp->v_rdev == NULL) {
228		dev_unlock();
229		return (ENXIO);
230	}
231	error = linux_driver_get_major_minor(devtoname(vp->v_rdev),
232	    major, minor);
233	dev_unlock();
234	return (error);
235}
236
237char *
238linux_get_char_devices()
239{
240	struct device_element *de;
241	char *temp, *string, *last;
242	char formated[256];
243	int current_size = 0, string_size = 1024;
244
245	string = malloc(string_size, M_LINUX, M_WAITOK);
246	string[0] = '\000';
247	last = "";
248	TAILQ_FOREACH(de, &devices, list) {
249		if (!de->entry.linux_char_device)
250			continue;
251		temp = string;
252		if (strcmp(last, de->entry.bsd_driver_name) != 0) {
253			last = de->entry.bsd_driver_name;
254
255			snprintf(formated, sizeof(formated), "%3d %s\n",
256				 de->entry.linux_major,
257				 de->entry.linux_device_name);
258			if (strlen(formated) + current_size
259			    >= string_size) {
260				string_size *= 2;
261				string = malloc(string_size,
262				    M_LINUX, M_WAITOK);
263				bcopy(temp, string, current_size);
264				free(temp, M_LINUX);
265			}
266			strcat(string, formated);
267			current_size = strlen(string);
268		}
269	}
270
271	return (string);
272}
273
274void
275linux_free_get_char_devices(char *string)
276{
277
278	free(string, M_LINUX);
279}
280
281static int linux_major_starting = 200;
282
283int
284linux_device_register_handler(struct linux_device_handler *d)
285{
286	struct device_element *de;
287
288	if (d == NULL)
289		return (EINVAL);
290
291	de = malloc(sizeof(*de), M_LINUX, M_WAITOK);
292	if (d->linux_major < 0) {
293		d->linux_major = linux_major_starting++;
294	}
295	bcopy(d, &de->entry, sizeof(*d));
296
297	/* Add the element to the list, sorted on span. */
298	TAILQ_INSERT_TAIL(&devices, de, list);
299
300	return (0);
301}
302
303int
304linux_device_unregister_handler(struct linux_device_handler *d)
305{
306	struct device_element *de;
307
308	if (d == NULL)
309		return (EINVAL);
310
311	TAILQ_FOREACH(de, &devices, list) {
312		if (bcmp(d, &de->entry, sizeof(*d)) == 0) {
313			TAILQ_REMOVE(&devices, de, list);
314			free(de, M_LINUX);
315
316			return (0);
317		}
318	}
319
320	return (EINVAL);
321}
322