xref: /titanic_41/usr/src/uts/common/io/dump.c (revision 355b4669e025ff377602b6fc7caaf30dbc218371)
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, Version 1.0 only
6  * (the "License").  You may not use this file except in compliance
7  * with the License.
8  *
9  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
10  * or http://www.opensolaris.org/os/licensing.
11  * See the License for the specific language governing permissions
12  * and limitations under the License.
13  *
14  * When distributing Covered Code, include this CDDL HEADER in each
15  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
16  * If applicable, add the following below this CDDL HEADER, with the
17  * fields enclosed by brackets "[]" replaced with your own identifying
18  * information: Portions Copyright [yyyy] [name of copyright owner]
19  *
20  * CDDL HEADER END
21  */
22 /*
23  * Copyright 2002 Sun Microsystems, Inc.  All rights reserved.
24  * Use is subject to license terms.
25  */
26 
27 #pragma ident	"%Z%%M%	%I%	%E% SMI"
28 
29 /*
30  * Dump driver.  Provides ioctls to get/set crash dump configuration.
31  */
32 
33 #include <sys/types.h>
34 #include <sys/param.h>
35 #include <sys/systm.h>
36 #include <sys/vnode.h>
37 #include <sys/uio.h>
38 #include <sys/cred.h>
39 #include <sys/kmem.h>
40 #include <sys/errno.h>
41 #include <sys/modctl.h>
42 #include <sys/dumphdr.h>
43 #include <sys/dumpadm.h>
44 #include <sys/pathname.h>
45 #include <sys/file.h>
46 #include <vm/anon.h>
47 #include <sys/stat.h>
48 #include <sys/conf.h>
49 #include <sys/ddi.h>
50 #include <sys/sunddi.h>
51 
52 static dev_info_t *dump_devi;
53 
54 static int
55 dump_attach(dev_info_t *devi, ddi_attach_cmd_t cmd)
56 {
57 	if (cmd != DDI_ATTACH)
58 		return (DDI_FAILURE);
59 	if (ddi_create_minor_node(devi, "dump", S_IFCHR, 0, DDI_PSEUDO, NULL) ==
60 	    DDI_FAILURE) {
61 		ddi_remove_minor_node(devi, NULL);
62 		return (DDI_FAILURE);
63 	}
64 	dump_devi = devi;
65 	return (DDI_SUCCESS);
66 }
67 
68 static int
69 dump_detach(dev_info_t *devi, ddi_detach_cmd_t cmd)
70 {
71 	if (cmd != DDI_DETACH)
72 		return (DDI_FAILURE);
73 	ddi_remove_minor_node(devi, NULL);
74 	return (DDI_SUCCESS);
75 }
76 
77 /*ARGSUSED*/
78 static int
79 dump_info(dev_info_t *dip, ddi_info_cmd_t infocmd, void *arg, void **result)
80 {
81 	switch (infocmd) {
82 	case DDI_INFO_DEVT2DEVINFO:
83 		*result = dump_devi;
84 		return (DDI_SUCCESS);
85 	case DDI_INFO_DEVT2INSTANCE:
86 		*result = 0;
87 		return (DDI_SUCCESS);
88 	}
89 	return (DDI_FAILURE);
90 }
91 
92 /*ARGSUSED*/
93 int
94 dump_ioctl(dev_t dev, int cmd, intptr_t arg, int mode, cred_t *cred, int *rvalp)
95 {
96 	uint64_t size;
97 	uint64_t dumpsize_in_pages;
98 	int error = 0;
99 	char *pathbuf = kmem_zalloc(MAXPATHLEN, KM_SLEEP);
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 						segvn_pages_locked -
124 						pages_locked -
125 						pages_claimed -
126 						pages_useclaim);
127 
128 			size = ptob(dumpsize_in_pages) / DUMP_COMPRESS_RATIO;
129 		}
130 		if (copyout(&size, (void *)arg, sizeof (size)) < 0)
131 			error = EFAULT;
132 		break;
133 
134 	case DIOCGETCONF:
135 		mutex_enter(&dump_lock);
136 		*rvalp = dump_conflags;
137 		if (dumpvp && !(dumpvp->v_flag & VISSWAP))
138 			*rvalp |= DUMP_EXCL;
139 		mutex_exit(&dump_lock);
140 		break;
141 
142 	case DIOCSETCONF:
143 		mutex_enter(&dump_lock);
144 		if (arg == DUMP_KERNEL || arg == DUMP_ALL ||
145 		    arg == DUMP_CURPROC)
146 			dump_conflags = arg;
147 		else
148 			error = EINVAL;
149 		mutex_exit(&dump_lock);
150 		break;
151 
152 	case DIOCGETDEV:
153 		mutex_enter(&dump_lock);
154 		if (dumppath == NULL) {
155 			mutex_exit(&dump_lock);
156 			error = ENODEV;
157 			break;
158 		}
159 		(void) strcpy(pathbuf, dumppath);
160 		mutex_exit(&dump_lock);
161 		error = copyoutstr(pathbuf, (void *)arg, MAXPATHLEN, NULL);
162 		break;
163 
164 	case DIOCSETDEV:
165 	case DIOCTRYDEV:
166 		if ((error = copyinstr((char *)arg, pathbuf, MAXPATHLEN,
167 		    NULL)) != 0 || (error = lookupname(pathbuf, UIO_SYSSPACE,
168 		    FOLLOW, NULLVPP, &vp)) != 0)
169 			break;
170 		mutex_enter(&dump_lock);
171 		error = dumpinit(vp, pathbuf, cmd == DIOCTRYDEV);
172 		mutex_exit(&dump_lock);
173 		VN_RELE(vp);
174 		break;
175 
176 	case DIOCDUMP:
177 		mutex_enter(&dump_lock);
178 		if (dumpvp == NULL)
179 			error = ENODEV;
180 		else if (dumpvp->v_flag & VISSWAP)
181 			error = EBUSY;
182 		else
183 			dumpsys();
184 		mutex_exit(&dump_lock);
185 		break;
186 
187 	default:
188 		error = ENXIO;
189 	}
190 
191 	kmem_free(pathbuf, MAXPATHLEN);
192 	return (error);
193 }
194 
195 struct cb_ops dump_cb_ops = {
196 	nulldev,		/* open */
197 	nulldev,		/* close */
198 	nodev,			/* strategy */
199 	nodev,			/* print */
200 	nodev,			/* dump */
201 	nodev,			/* read */
202 	nodev,			/* write */
203 	dump_ioctl,		/* ioctl */
204 	nodev,			/* devmap */
205 	nodev,			/* mmap */
206 	nodev, 			/* segmap */
207 	nochpoll,		/* poll */
208 	ddi_prop_op,		/* prop_op */
209 	0,			/* streamtab  */
210 	D_NEW|D_MP		/* Driver compatibility flag */
211 };
212 
213 struct dev_ops dump_ops = {
214 	DEVO_REV,		/* devo_rev, */
215 	0,			/* refcnt */
216 	dump_info,		/* info */
217 	nulldev,		/* identify */
218 	nulldev,		/* probe */
219 	dump_attach,		/* attach */
220 	dump_detach,		/* detach */
221 	nodev,			/* reset */
222 	&dump_cb_ops,		/* driver operations */
223 	(struct bus_ops *)0	/* bus operations */
224 };
225 
226 static struct modldrv modldrv = {
227 	&mod_driverops, "crash dump driver %I%", &dump_ops,
228 };
229 
230 static struct modlinkage modlinkage = {
231 	MODREV_1, (void *)&modldrv, NULL
232 };
233 
234 int
235 _init(void)
236 {
237 	return (mod_install(&modlinkage));
238 }
239 
240 int
241 _fini(void)
242 {
243 	return (mod_remove(&modlinkage));
244 }
245 
246 int
247 _info(struct modinfo *modinfop)
248 {
249 	return (mod_info(&modlinkage, modinfop));
250 }
251