1/*-
2 * Copyright (c) 1994 Christos Zoulas
3 * Copyright (c) 1995 Frank van der Linden
4 * Copyright (c) 1995 Scott Bartram
5 * All rights reserved.
6 *
7 * Redistribution and use in source and binary forms, with or without
8 * modification, are permitted provided that the following conditions
9 * are met:
10 * 1. Redistributions of source code must retain the above copyright
11 *    notice, this list of conditions and the following disclaimer.
12 * 2. Redistributions in binary form must reproduce the above copyright
13 *    notice, this list of conditions and the following disclaimer in the
14 *    documentation and/or other materials provided with the distribution.
15 * 3. The name of the author may not be used to endorse or promote products
16 *    derived from this software without specific prior written permission
17 *
18 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
19 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
20 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
21 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
22 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
23 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
24 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
25 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
26 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
27 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
28 *
29 *	from: svr4_util.c,v 1.5 1995/01/22 23:44:50 christos Exp
30 */
31
32#include <sys/cdefs.h>
33__FBSDID("$FreeBSD$");
34
35#include "opt_compat.h"
36#include "opt_kdtrace.h"
37
38#include <sys/param.h>
39#include <sys/bus.h>
40#include <sys/fcntl.h>
41#include <sys/lock.h>
42#include <sys/malloc.h>
43#include <sys/kernel.h>
44#include <sys/linker_set.h>
45#include <sys/mutex.h>
46#include <sys/namei.h>
47#include <sys/proc.h>
48#include <sys/sdt.h>
49#include <sys/syscallsubr.h>
50#include <sys/systm.h>
51#include <sys/vnode.h>
52
53#include <machine/stdarg.h>
54
55#include <compat/linux/linux_util.h>
56#ifdef COMPAT_LINUX32
57#include <machine/../linux32/linux.h>
58#else
59#include <machine/../linux/linux.h>
60#endif
61
62#include <compat/linux/linux_dtrace.h>
63
64const char      linux_emul_path[] = "/compat/linux";
65
66/* DTrace init */
67LIN_SDT_PROVIDER_DECLARE(LINUX_DTRACE);
68
69/**
70 * DTrace probes in this module.
71 */
72LIN_SDT_PROBE_DEFINE5(util, linux_emul_convpath, entry, "const char *",
73    "enum uio_seg", "char **", "int", "int");
74LIN_SDT_PROBE_DEFINE1(util, linux_emul_convpath, return, "int");
75LIN_SDT_PROBE_DEFINE1(util, linux_msg, entry, "const char *");
76LIN_SDT_PROBE_DEFINE0(util, linux_msg, return);
77LIN_SDT_PROBE_DEFINE2(util, linux_driver_get_name_dev, entry, "device_t",
78    "const char *");
79LIN_SDT_PROBE_DEFINE0(util, linux_driver_get_name_dev, nullcall);
80LIN_SDT_PROBE_DEFINE1(util, linux_driver_get_name_dev, return, "char *");
81LIN_SDT_PROBE_DEFINE3(util, linux_driver_get_major_minor, entry, "char *",
82    "int *", "int *");
83LIN_SDT_PROBE_DEFINE0(util, linux_driver_get_major_minor, nullcall);
84LIN_SDT_PROBE_DEFINE1(util, linux_driver_get_major_minor, notfound, "char *");
85LIN_SDT_PROBE_DEFINE3(util, linux_driver_get_major_minor, return, "int",
86    "int", "int");
87LIN_SDT_PROBE_DEFINE0(util, linux_get_char_devices, entry);
88LIN_SDT_PROBE_DEFINE1(util, linux_get_char_devices, return, "char *");
89LIN_SDT_PROBE_DEFINE1(util, linux_free_get_char_devices, entry, "char *");
90LIN_SDT_PROBE_DEFINE0(util, linux_free_get_char_devices, return);
91LIN_SDT_PROBE_DEFINE1(util, linux_device_register_handler, entry,
92    "struct linux_device_handler *");
93LIN_SDT_PROBE_DEFINE1(util, linux_device_register_handler, return, "int");
94LIN_SDT_PROBE_DEFINE1(util, linux_device_unregister_handler, entry,
95    "struct linux_device_handler *");
96LIN_SDT_PROBE_DEFINE1(util, linux_device_unregister_handler, return, "int");
97
98/*
99 * Search an alternate path before passing pathname arguments on to
100 * system calls. Useful for keeping a separate 'emulation tree'.
101 *
102 * If cflag is set, we check if an attempt can be made to create the
103 * named file, i.e. we check if the directory it should be in exists.
104 */
105int
106linux_emul_convpath(struct thread *td, const char *path, enum uio_seg pathseg,
107    char **pbuf, int cflag, int dfd)
108{
109	int retval;
110
111	LIN_SDT_PROBE5(util, linux_emul_convpath, entry, path, pathseg, pbuf,
112	    cflag, dfd);
113
114	retval = kern_alternate_path(td, linux_emul_path, path, pathseg, pbuf,
115	    cflag, dfd);
116
117	LIN_SDT_PROBE1(util, linux_emul_convpath, return, retval);
118	return (retval);
119}
120
121void
122linux_msg(const struct thread *td, const char *fmt, ...)
123{
124	va_list ap;
125	struct proc *p;
126
127	LIN_SDT_PROBE1(util, linux_msg, entry, fmt);
128
129	p = td->td_proc;
130	printf("linux: pid %d (%s): ", (int)p->p_pid, p->p_comm);
131	va_start(ap, fmt);
132	vprintf(fmt, ap);
133	va_end(ap);
134	printf("\n");
135
136	LIN_SDT_PROBE0(util, linux_msg, return);
137}
138
139struct device_element
140{
141	TAILQ_ENTRY(device_element) list;
142	struct linux_device_handler entry;
143};
144
145static TAILQ_HEAD(, device_element) devices =
146	TAILQ_HEAD_INITIALIZER(devices);
147
148static struct linux_device_handler null_handler =
149	{ "mem", "mem", "null", "null", 1, 3, 1};
150
151DATA_SET(linux_device_handler_set, null_handler);
152
153char *
154linux_driver_get_name_dev(device_t dev)
155{
156	struct device_element *de;
157	const char *device_name = device_get_name(dev);
158
159	LIN_SDT_PROBE2(util, linux_driver_get_name_dev, entry, dev,
160	    device_name);
161
162	if (device_name == NULL) {
163		LIN_SDT_PROBE0(util, linux_driver_get_name_dev, nullcall);
164		LIN_SDT_PROBE1(util, linux_driver_get_name_dev, return, NULL);
165		return NULL;
166	}
167	TAILQ_FOREACH(de, &devices, list) {
168		if (strcmp(device_name, de->entry.bsd_driver_name) == 0) {
169			LIN_SDT_PROBE1(util, linux_driver_get_name_dev, return,
170			    de->entry.linux_driver_name);
171			return (de->entry.linux_driver_name);
172		}
173	}
174
175	LIN_SDT_PROBE1(util, linux_driver_get_name_dev, return, NULL);
176	return NULL;
177}
178
179int
180linux_driver_get_major_minor(const char *node, int *major, int *minor)
181{
182	struct device_element *de;
183
184	LIN_SDT_PROBE3(util, linux_driver_get_major_minor, entry, node, major,
185	    minor);
186
187	if (node == NULL || major == NULL || minor == NULL) {
188		LIN_SDT_PROBE0(util, linux_driver_get_major_minor, nullcall);
189		LIN_SDT_PROBE3(util, linux_driver_get_major_minor, return, 1,
190		   0, 0);
191		return 1;
192	}
193
194	if (strlen(node) > strlen("pts/") &&
195	    strncmp(node, "pts/", strlen("pts/")) == 0) {
196		unsigned long devno;
197
198		/*
199		 * Linux checks major and minors of the slave device
200		 * to make sure it's a pty device, so let's make him
201		 * believe it is.
202		 */
203		devno = strtoul(node + strlen("pts/"), NULL, 10);
204		*major = 136 + (devno / 256);
205		*minor = devno % 256;
206
207		LIN_SDT_PROBE3(util, linux_driver_get_major_minor, return, 0,
208		    *major, *minor);
209		return 0;
210	}
211
212	TAILQ_FOREACH(de, &devices, list) {
213		if (strcmp(node, de->entry.bsd_device_name) == 0) {
214			*major = de->entry.linux_major;
215			*minor = de->entry.linux_minor;
216
217			LIN_SDT_PROBE3(util, linux_driver_get_major_minor,
218			    return, 0, *major, *minor);
219			return 0;
220		}
221	}
222
223	LIN_SDT_PROBE1(util, linux_driver_get_major_minor, notfound, node);
224	LIN_SDT_PROBE3(util, linux_driver_get_major_minor, return, 1, 0, 0);
225	return 1;
226}
227
228char *
229linux_get_char_devices()
230{
231	struct device_element *de;
232	char *temp, *string, *last;
233	char formated[256];
234	int current_size = 0, string_size = 1024;
235
236	LIN_SDT_PROBE0(util, linux_get_char_devices, entry);
237
238	string = malloc(string_size, M_LINUX, M_WAITOK);
239	string[0] = '\000';
240	last = "";
241	TAILQ_FOREACH(de, &devices, list) {
242		if (!de->entry.linux_char_device)
243			continue;
244		temp = string;
245		if (strcmp(last, de->entry.bsd_driver_name) != 0) {
246			last = de->entry.bsd_driver_name;
247
248			snprintf(formated, sizeof(formated), "%3d %s\n",
249				 de->entry.linux_major,
250				 de->entry.linux_device_name);
251			if (strlen(formated) + current_size
252			    >= string_size) {
253				string_size *= 2;
254				string = malloc(string_size,
255				    M_LINUX, M_WAITOK);
256				bcopy(temp, string, current_size);
257				free(temp, M_LINUX);
258			}
259			strcat(string, formated);
260			current_size = strlen(string);
261		}
262	}
263
264	LIN_SDT_PROBE1(util, linux_get_char_devices, return, string);
265	return string;
266}
267
268void
269linux_free_get_char_devices(char *string)
270{
271
272	LIN_SDT_PROBE1(util, linux_get_char_devices, entry, string);
273
274	free(string, M_LINUX);
275
276	LIN_SDT_PROBE0(util, linux_get_char_devices, return);
277}
278
279static int linux_major_starting = 200;
280
281int
282linux_device_register_handler(struct linux_device_handler *d)
283{
284	struct device_element *de;
285
286	LIN_SDT_PROBE1(util, linux_device_register_handler, entry, d);
287
288	if (d == NULL) {
289		LIN_SDT_PROBE1(util, linux_device_register_handler, return,
290		    EINVAL);
291		return (EINVAL);
292	}
293
294	de = malloc(sizeof(*de), M_LINUX, M_WAITOK);
295	if (d->linux_major < 0) {
296		d->linux_major = linux_major_starting++;
297	}
298	bcopy(d, &de->entry, sizeof(*d));
299
300	/* Add the element to the list, sorted on span. */
301	TAILQ_INSERT_TAIL(&devices, de, list);
302
303	LIN_SDT_PROBE1(util, linux_device_register_handler, return, 0);
304	return (0);
305}
306
307int
308linux_device_unregister_handler(struct linux_device_handler *d)
309{
310	struct device_element *de;
311
312	LIN_SDT_PROBE1(util, linux_device_unregister_handler, entry, d);
313
314	if (d == NULL) {
315		LIN_SDT_PROBE1(util, linux_device_unregister_handler, return,
316		    EINVAL);
317		return (EINVAL);
318	}
319
320	TAILQ_FOREACH(de, &devices, list) {
321		if (bcmp(d, &de->entry, sizeof(*d)) == 0) {
322			TAILQ_REMOVE(&devices, de, list);
323			free(de, M_LINUX);
324
325			LIN_SDT_PROBE1(util, linux_device_unregister_handler,
326			    return, 0);
327			return (0);
328		}
329	}
330
331	LIN_SDT_PROBE1(util, linux_device_unregister_handler, return, EINVAL);
332	return (EINVAL);
333}
334