xref: /illumos-gate/usr/src/cmd/syseventd/modules/datalink_mod/datalink_mod.c (revision 0756cc7034e080027082817163d21e36e93310ed)
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 /*
23  * Copyright 2009 Sun Microsystems, Inc.  All rights reserved.
24  * Use is subject to license terms.
25  * Copyright 2016 Nexenta Systems, Inc.
26  */
27 
28 /*
29  * datalink syseventd module.
30  *
31  * The purpose of this module is to identify all datalink related events,
32  * and react accordingly.
33  */
34 
35 #include <errno.h>
36 #include <sys/sysevent/eventdefs.h>
37 #include <string.h>
38 #include <libnvpair.h>
39 #include <librcm.h>
40 #include <libsysevent.h>
41 #include "sysevent_signal.h"
42 
43 extern void syseventd_err_print(char *, ...);
44 
45 struct event_list {
46 	nvlist_t *ev;
47 	struct event_list *next;
48 };
49 
50 static rcm_handle_t *rcm_hdl = NULL;
51 static boolean_t dl_exiting;
52 static thread_t dl_notify_tid;
53 static mutex_t dl_mx;
54 static cond_t dl_cv;
55 static struct event_list *dl_events;
56 
57 /* ARGSUSED */
58 static void *
datalink_notify_thread(void * arg)59 datalink_notify_thread(void *arg)
60 {
61 	struct event_list *tmp_events, *ep;
62 
63 	(void) mutex_lock(&dl_mx);
64 
65 	while (! dl_exiting || dl_events != NULL) {
66 		if (dl_events == NULL) {
67 			(void) cond_wait(&dl_cv, &dl_mx);
68 			continue;
69 		}
70 
71 		tmp_events = dl_events;
72 		dl_events = NULL;
73 
74 		(void) mutex_unlock(&dl_mx);
75 
76 		while (tmp_events != NULL) {
77 			struct sigaction cbuf, dfl;
78 
79 			/*
80 			 * Ignore SIGCLD for the
81 			 * duration of the rcm_notify_event call.
82 			 */
83 			(void) memset(&dfl, 0, sizeof (dfl));
84 			dfl.sa_handler = SIG_IGN;
85 			(void) sigaction(SIGCHLD, &dfl, &cbuf);
86 
87 			/*
88 			 * Send the PHYSLINK_NEW event to network_rcm to update
89 			 * the network devices cache accordingly.
90 			 */
91 			if (rcm_notify_event(rcm_hdl, RCM_RESOURCE_PHYSLINK_NEW,
92 			    0, tmp_events->ev, NULL) != RCM_SUCCESS)
93 				syseventd_err_print("datalink_mod: Can not "
94 				    "notify event: %s\n", strerror(errno));
95 
96 			(void) sigaction(SIGCHLD, &cbuf, NULL);
97 			ep = tmp_events;
98 			tmp_events = tmp_events->next;
99 			nvlist_free(ep->ev);
100 			free(ep);
101 		}
102 
103 		(void) mutex_lock(&dl_mx);
104 	}
105 
106 	(void) mutex_unlock(&dl_mx);
107 
108 	return (NULL);
109 }
110 
111 /*ARGSUSED*/
112 static int
datalink_deliver_event(sysevent_t * ev,int unused)113 datalink_deliver_event(sysevent_t *ev, int unused)
114 {
115 	const char *class = sysevent_get_class_name(ev);
116 	const char *subclass = sysevent_get_subclass_name(ev);
117 	nvlist_t *nvl;
118 	struct event_list *newp, **elpp;
119 
120 	if (strcmp(class, EC_DATALINK) != 0 ||
121 	    strcmp(subclass, ESC_DATALINK_PHYS_ADD) != 0) {
122 		return (0);
123 	}
124 
125 	if (sysevent_get_attr_list(ev, &nvl) != 0)
126 		return (EINVAL);
127 
128 	/*
129 	 * rcm_notify_event() needs to be called asynchronously otherwise when
130 	 * sysevent queue is full, deadlock will happen.
131 	 */
132 	if ((newp = malloc(sizeof (struct event_list))) == NULL)
133 		return (ENOMEM);
134 
135 	newp->ev = nvl;
136 	newp->next = NULL;
137 
138 	/*
139 	 * queue up at the end of the event list and signal notify_thread to
140 	 * process it.
141 	 */
142 	(void) mutex_lock(&dl_mx);
143 	elpp = &dl_events;
144 	while (*elpp !=  NULL)
145 		elpp = &(*elpp)->next;
146 	*elpp = newp;
147 	(void) cond_signal(&dl_cv);
148 	(void) mutex_unlock(&dl_mx);
149 
150 	return (0);
151 }
152 
153 static struct slm_mod_ops datalink_mod_ops = {
154 	SE_MAJOR_VERSION,
155 	SE_MINOR_VERSION,
156 	SE_MAX_RETRY_LIMIT,
157 	datalink_deliver_event
158 };
159 
160 struct slm_mod_ops *
slm_init()161 slm_init()
162 {
163 	dl_events = NULL;
164 	dl_exiting = B_FALSE;
165 
166 	if (rcm_alloc_handle(NULL, 0, NULL, &rcm_hdl) != RCM_SUCCESS)
167 		return (NULL);
168 
169 	(void) mutex_init(&dl_mx, USYNC_THREAD, NULL);
170 	(void) cond_init(&dl_cv, USYNC_THREAD, NULL);
171 
172 	if (thr_create(NULL, 0,  datalink_notify_thread, NULL, 0,
173 	    &dl_notify_tid) != 0) {
174 		(void) rcm_free_handle(rcm_hdl);
175 		(void) mutex_destroy(&dl_mx);
176 		(void) cond_destroy(&dl_cv);
177 		return (NULL);
178 	}
179 
180 	return (&datalink_mod_ops);
181 }
182 
183 void
slm_fini()184 slm_fini()
185 {
186 	(void) mutex_lock(&dl_mx);
187 	dl_exiting = B_TRUE;
188 	(void) cond_signal(&dl_cv);
189 	(void) mutex_unlock(&dl_mx);
190 	(void) thr_join(dl_notify_tid, NULL, NULL);
191 
192 	(void) mutex_destroy(&dl_mx);
193 	(void) cond_destroy(&dl_cv);
194 	(void) rcm_free_handle(rcm_hdl);
195 	rcm_hdl = NULL;
196 }
197