1 /*
2 * CDDL HEADER START
3 *
4 * The contents of this file are subject to the terms of the
5 * Common Development and Distribution License (the "License").
6 * You may not use this file except in compliance with the License.
7 *
8 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
9 * or http://www.opensolaris.org/os/licensing.
10 * See the License for the specific language governing permissions
11 * and limitations under the License.
12 *
13 * When distributing Covered Code, include this CDDL HEADER in each
14 * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
15 * If applicable, add the following below this CDDL HEADER, with the
16 * fields enclosed by brackets "[]" replaced with your own identifying
17 * information: Portions Copyright [yyyy] [name of copyright owner]
18 *
19 * CDDL HEADER END
20 */
21 /*
22 * Copyright (c) 1998, 2010, Oracle and/or its affiliates. All rights reserved.
23 * Delphix (c) 2012 by Delphix. All rights reserved.
24 */
25
26
27 /*
28 * Dump driver. Provides ioctls to get/set crash dump configuration.
29 */
30
31 #include <sys/types.h>
32 #include <sys/param.h>
33 #include <sys/systm.h>
34 #include <sys/vnode.h>
35 #include <sys/uio.h>
36 #include <sys/cred.h>
37 #include <sys/kmem.h>
38 #include <sys/errno.h>
39 #include <sys/modctl.h>
40 #include <sys/dumphdr.h>
41 #include <sys/dumpadm.h>
42 #include <sys/pathname.h>
43 #include <sys/file.h>
44 #include <vm/anon.h>
45 #include <sys/stat.h>
46 #include <sys/conf.h>
47 #include <sys/ddi.h>
48 #include <sys/sunddi.h>
49
50 static dev_info_t *dump_devi;
51
52 static int
53 dump_attach(dev_info_t *devi, ddi_attach_cmd_t cmd)
54 {
55 if (cmd != DDI_ATTACH)
56 return (DDI_FAILURE);
57 if (ddi_create_minor_node(devi, "dump", S_IFCHR, 0, DDI_PSEUDO, NULL) ==
58 DDI_FAILURE) {
59 ddi_remove_minor_node(devi, NULL);
60 return (DDI_FAILURE);
61 }
62 dump_devi = devi;
63 return (DDI_SUCCESS);
64 }
65
66 static int
67 dump_detach(dev_info_t *devi, ddi_detach_cmd_t cmd)
68 {
69 if (cmd != DDI_DETACH)
70 return (DDI_FAILURE);
71 ddi_remove_minor_node(devi, NULL);
72 return (DDI_SUCCESS);
73 }
74
75 /*ARGSUSED*/
76 static int
77 dump_info(dev_info_t *dip, ddi_info_cmd_t infocmd, void *arg, void **result)
78 {
79 switch (infocmd) {
80 case DDI_INFO_DEVT2DEVINFO:
81 *result = dump_devi;
82 return (DDI_SUCCESS);
83 case DDI_INFO_DEVT2INSTANCE:
84 *result = 0;
85 return (DDI_SUCCESS);
86 }
87 return (DDI_FAILURE);
88 }
89
90 /*ARGSUSED*/
91 int
92 dump_ioctl(dev_t dev, int cmd, intptr_t arg, int mode, cred_t *cred, int *rvalp)
93 {
94 uint64_t size;
95 uint64_t dumpsize_in_pages;
96 int error = 0;
97 char *pathbuf = kmem_zalloc(MAXPATHLEN, KM_SLEEP);
98 char uuidbuf[36 + 1];
99 size_t len;
100 vnode_t *vp;
101
102 switch (cmd) {
103 case DIOCGETDUMPSIZE:
104 if (dump_conflags & DUMP_ALL)
105 size = ptob((uint64_t)physmem) / DUMP_COMPRESS_RATIO;
106 else {
107 /*
108 * We can't give a good answer for the DUMP_CURPROC
109 * because we won't know which process to use until it
110 * causes a panic. We'll therefore punt and give the
111 * caller the size for the kernel.
112 *
113 * This kernel size equation takes care of the
114 * boot time kernel footprint and also accounts
115 * for availrmem changes due to user explicit locking.
116 * Refer to common/vm/vm_page.c for an explanation
117 * of these counters.
118 */
119 dumpsize_in_pages = (physinstalled - obp_pages -
120 availrmem -
121 anon_segkp_pages_locked -
122 k_anoninfo.ani_mem_resv -
123 pages_locked -
124 pages_claimed -
125 pages_useclaim);
126
127 /*
128 * Protect against vm vagaries.
129 */
130 if (dumpsize_in_pages > (uint64_t)physmem)
131 dumpsize_in_pages = (uint64_t)physmem;
132
133 size = ptob(dumpsize_in_pages) / DUMP_COMPRESS_RATIO;
134 }
135 if (copyout(&size, (void *)arg, sizeof (size)) < 0)
136 error = EFAULT;
137 break;
138
139 case DIOCGETCONF:
140 mutex_enter(&dump_lock);
141 *rvalp = dump_conflags;
142 if (dumpvp && !(dumpvp->v_flag & VISSWAP))
143 *rvalp |= DUMP_EXCL;
144 mutex_exit(&dump_lock);
145 break;
146
147 case DIOCSETCONF:
148 mutex_enter(&dump_lock);
149 if (arg == DUMP_KERNEL || arg == DUMP_ALL ||
150 arg == DUMP_CURPROC)
151 dump_conflags = arg;
152 else
153 error = EINVAL;
154 mutex_exit(&dump_lock);
155 break;
156
157 case DIOCGETDEV:
158 mutex_enter(&dump_lock);
159 if (dumppath == NULL) {
160 mutex_exit(&dump_lock);
161 error = ENODEV;
162 break;
163 }
164 (void) strcpy(pathbuf, dumppath);
165 mutex_exit(&dump_lock);
166 error = copyoutstr(pathbuf, (void *)arg, MAXPATHLEN, NULL);
167 break;
168
169 case DIOCSETDEV:
170 case DIOCTRYDEV:
171 if ((error = copyinstr((char *)arg, pathbuf, MAXPATHLEN,
172 NULL)) != 0 || (error = lookupname(pathbuf, UIO_SYSSPACE,
173 FOLLOW, NULLVPP, &vp)) != 0)
174 break;
175 mutex_enter(&dump_lock);
176 if (vp->v_type == VBLK)
177 error = dumpinit(vp, pathbuf, cmd == DIOCTRYDEV);
178 else
179 error = ENOTBLK;
180 mutex_exit(&dump_lock);
181 VN_RELE(vp);
182 break;
183
184 case DIOCDUMP:
185 mutex_enter(&dump_lock);
186 if (dumpvp == NULL)
187 error = ENODEV;
188 else if (dumpvp->v_flag & VISSWAP)
189 error = EBUSY;
190 else
191 dumpsys();
192 mutex_exit(&dump_lock);
193 break;
194
195 case DIOCSETUUID:
196 if ((error = copyinstr((char *)arg, uuidbuf, sizeof (uuidbuf),
197 &len)) != 0)
198 break;
199
200 if (len != 37) {
201 error = EINVAL;
202 break;
203 }
204
205 error = dump_set_uuid(uuidbuf);
206 break;
207
208 case DIOCGETUUID:
209 error = copyoutstr(dump_get_uuid(), (void *)arg, 37, NULL);
210 break;
211
212 case DIOCRMDEV:
213 mutex_enter(&dump_lock);
214 if (dumpvp != NULL)
215 dumpfini();
216 mutex_exit(&dump_lock);
217 break;
218
219 default:
220 error = ENXIO;
221 }
222
223 kmem_free(pathbuf, MAXPATHLEN);
224 return (error);
225 }
226
227 struct cb_ops dump_cb_ops = {
228 nulldev, /* open */
229 nulldev, /* close */
230 nodev, /* strategy */
231 nodev, /* print */
232 nodev, /* dump */
233 nodev, /* read */
234 nodev, /* write */
235 dump_ioctl, /* ioctl */
236 nodev, /* devmap */
237 nodev, /* mmap */
238 nodev, /* segmap */
239 nochpoll, /* poll */
240 ddi_prop_op, /* prop_op */
241 0, /* streamtab */
242 D_NEW|D_MP /* Driver compatibility flag */
243 };
244
245 struct dev_ops dump_ops = {
246 DEVO_REV, /* devo_rev, */
247 0, /* refcnt */
248 dump_info, /* info */
249 nulldev, /* identify */
250 nulldev, /* probe */
251 dump_attach, /* attach */
252 dump_detach, /* detach */
253 nodev, /* reset */
254 &dump_cb_ops, /* driver operations */
255 (struct bus_ops *)0, /* bus operations */
256 NULL, /* power */
257 ddi_quiesce_not_needed, /* quiesce */
258 };
259
260 static struct modldrv modldrv = {
261 &mod_driverops, "crash dump driver", &dump_ops,
262 };
263
264 static struct modlinkage modlinkage = {
265 MODREV_1, (void *)&modldrv, NULL
266 };
267
268 int
269 _init(void)
270 {
271 return (mod_install(&modlinkage));
272 }
273
274 int
275 _fini(void)
276 {
277 return (mod_remove(&modlinkage));
278 }
279
280 int
281 _info(struct modinfo *modinfop)
282 {
283 return (mod_info(&modlinkage, modinfop));
284 }