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: stable/10/sys/compat/linux/linux_util.c 293546 2016-01-09 16:44:17Z dchagin $");
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
57 MALLOC_DEFINE(M_LINUX, "linux", "Linux mode structures");
58 MALLOC_DEFINE(M_EPOLL, "lepoll", "Linux events structures");
59 MALLOC_DEFINE(M_FUTEX, "futex", "Linux futexes");
60 MALLOC_DEFINE(M_FUTEX_WP, "futex wp", "Linux futex waiting proc");
61
62 const char linux_emul_path[] = "/compat/linux";
63
64 /*
65 * Search an alternate path before passing pathname arguments on to
66 * system calls. Useful for keeping a separate 'emulation tree'.
67 *
68 * If cflag is set, we check if an attempt can be made to create the
69 * named file, i.e. we check if the directory it should be in exists.
70 */
71 int
linux_emul_convpath(struct thread * td,const char * path,enum uio_seg pathseg,char ** pbuf,int cflag,int dfd)72 linux_emul_convpath(struct thread *td, const char *path, enum uio_seg pathseg,
73 char **pbuf, int cflag, int dfd)
74 {
75 int retval;
76
77 retval = kern_alternate_path(td, linux_emul_path, path, pathseg, pbuf,
78 cflag, dfd);
79
80 return (retval);
81 }
82
83 void
linux_msg(const struct thread * td,const char * fmt,...)84 linux_msg(const struct thread *td, const char *fmt, ...)
85 {
86 va_list ap;
87 struct proc *p;
88
89 p = td->td_proc;
90 printf("linux: pid %d (%s): ", (int)p->p_pid, p->p_comm);
91 va_start(ap, fmt);
92 vprintf(fmt, ap);
93 va_end(ap);
94 printf("\n");
95 }
96
97 struct device_element
98 {
99 TAILQ_ENTRY(device_element) list;
100 struct linux_device_handler entry;
101 };
102
103 static TAILQ_HEAD(, device_element) devices =
104 TAILQ_HEAD_INITIALIZER(devices);
105
106 static struct linux_device_handler null_handler =
107 { "mem", "mem", "null", "null", 1, 3, 1};
108
109 DATA_SET(linux_device_handler_set, null_handler);
110
111 char *
linux_driver_get_name_dev(device_t dev)112 linux_driver_get_name_dev(device_t dev)
113 {
114 struct device_element *de;
115 const char *device_name = device_get_name(dev);
116
117 if (device_name == NULL)
118 return NULL;
119 TAILQ_FOREACH(de, &devices, list) {
120 if (strcmp(device_name, de->entry.bsd_driver_name) == 0)
121 return (de->entry.linux_driver_name);
122 }
123
124 return (NULL);
125 }
126
127 int
linux_driver_get_major_minor(const char * node,int * major,int * minor)128 linux_driver_get_major_minor(const char *node, int *major, int *minor)
129 {
130 struct device_element *de;
131
132 if (node == NULL || major == NULL || minor == NULL)
133 return 1;
134
135 if (strlen(node) > strlen("pts/") &&
136 strncmp(node, "pts/", strlen("pts/")) == 0) {
137 unsigned long devno;
138
139 /*
140 * Linux checks major and minors of the slave device
141 * to make sure it's a pty device, so let's make him
142 * believe it is.
143 */
144 devno = strtoul(node + strlen("pts/"), NULL, 10);
145 *major = 136 + (devno / 256);
146 *minor = devno % 256;
147
148 return (0);
149 }
150
151 TAILQ_FOREACH(de, &devices, list) {
152 if (strcmp(node, de->entry.bsd_device_name) == 0) {
153 *major = de->entry.linux_major;
154 *minor = de->entry.linux_minor;
155 return (0);
156 }
157 }
158
159 return (1);
160 }
161
162 char *
linux_get_char_devices()163 linux_get_char_devices()
164 {
165 struct device_element *de;
166 char *temp, *string, *last;
167 char formated[256];
168 int current_size = 0, string_size = 1024;
169
170 string = malloc(string_size, M_LINUX, M_WAITOK);
171 string[0] = '\000';
172 last = "";
173 TAILQ_FOREACH(de, &devices, list) {
174 if (!de->entry.linux_char_device)
175 continue;
176 temp = string;
177 if (strcmp(last, de->entry.bsd_driver_name) != 0) {
178 last = de->entry.bsd_driver_name;
179
180 snprintf(formated, sizeof(formated), "%3d %s\n",
181 de->entry.linux_major,
182 de->entry.linux_device_name);
183 if (strlen(formated) + current_size
184 >= string_size) {
185 string_size *= 2;
186 string = malloc(string_size,
187 M_LINUX, M_WAITOK);
188 bcopy(temp, string, current_size);
189 free(temp, M_LINUX);
190 }
191 strcat(string, formated);
192 current_size = strlen(string);
193 }
194 }
195
196 return (string);
197 }
198
199 void
linux_free_get_char_devices(char * string)200 linux_free_get_char_devices(char *string)
201 {
202
203 free(string, M_LINUX);
204 }
205
206 static int linux_major_starting = 200;
207
208 int
linux_device_register_handler(struct linux_device_handler * d)209 linux_device_register_handler(struct linux_device_handler *d)
210 {
211 struct device_element *de;
212
213 if (d == NULL)
214 return (EINVAL);
215
216 de = malloc(sizeof(*de), M_LINUX, M_WAITOK);
217 if (d->linux_major < 0) {
218 d->linux_major = linux_major_starting++;
219 }
220 bcopy(d, &de->entry, sizeof(*d));
221
222 /* Add the element to the list, sorted on span. */
223 TAILQ_INSERT_TAIL(&devices, de, list);
224
225 return (0);
226 }
227
228 int
linux_device_unregister_handler(struct linux_device_handler * d)229 linux_device_unregister_handler(struct linux_device_handler *d)
230 {
231 struct device_element *de;
232
233 if (d == NULL)
234 return (EINVAL);
235
236 TAILQ_FOREACH(de, &devices, list) {
237 if (bcmp(d, &de->entry, sizeof(*d)) == 0) {
238 TAILQ_REMOVE(&devices, de, list);
239 free(de, M_LINUX);
240
241 return (0);
242 }
243 }
244
245 return (EINVAL);
246 }
247