xref: /illumos-gate/usr/src/uts/common/io/vscan/vscan_door.c (revision 0d2006e4703eda0f88de2e571bf9fb317552faa2)
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  */
26 
27 #include <sys/types.h>
28 #include <sys/errno.h>
29 #include <sys/kmem.h>
30 #include <sys/vnode.h>
31 #include <sys/pathname.h>
32 #include <sys/door.h>
33 #include <sys/cmn_err.h>
34 #include <sys/sunddi.h> /* for string functions */
35 #include <sys/vscan.h>
36 
37 #define	VS_DOOR_RETRIES			3
38 
39 /* max time (secs) to wait for door calls to complete during door_close */
40 #define	VS_DOOR_CLOSE_TIMEOUT_DEFAULT	30
41 uint32_t vs_door_close_timeout = VS_DOOR_CLOSE_TIMEOUT_DEFAULT;
42 
43 static door_handle_t vscan_door_handle = NULL;
44 static kmutex_t vscan_door_mutex;
45 static kcondvar_t vscan_door_cv;
46 static int vscan_door_call_count = 0;
47 
48 
49 /*
50  * vscan_door_init
51  */
52 int
53 vscan_door_init(void)
54 {
55 	mutex_init(&vscan_door_mutex, NULL, MUTEX_DEFAULT, NULL);
56 	cv_init(&vscan_door_cv, NULL, CV_DEFAULT, NULL);
57 	return (0);
58 }
59 
60 
61 /*
62  * vscan_door_fini
63  */
64 void
65 vscan_door_fini(void)
66 {
67 	mutex_destroy(&vscan_door_mutex);
68 	cv_destroy(&vscan_door_cv);
69 }
70 
71 
72 /*
73  * vscan_door_open
74  */
75 int
76 vscan_door_open(int door_id)
77 {
78 	mutex_enter(&vscan_door_mutex);
79 
80 	if (vscan_door_handle == NULL)
81 		vscan_door_handle = door_ki_lookup(door_id);
82 
83 	if (vscan_door_handle == NULL) {
84 		cmn_err(CE_WARN, "Internal communication error "
85 		    "- failed to access vscan service daemon.");
86 		mutex_exit(&vscan_door_mutex);
87 		return (-1);
88 	}
89 
90 	mutex_exit(&vscan_door_mutex);
91 	return (0);
92 }
93 
94 
95 /*
96  * vscan_door_close
97  */
98 void
99 vscan_door_close(void)
100 {
101 	clock_t timeout, time_left;
102 
103 	mutex_enter(&vscan_door_mutex);
104 
105 	/* wait for any in-progress requests to complete */
106 	time_left = SEC_TO_TICK(vs_door_close_timeout);
107 	while ((vscan_door_call_count > 0) && (time_left > 0)) {
108 		timeout = time_left;
109 		time_left = cv_reltimedwait(&vscan_door_cv, &vscan_door_mutex,
110 		    timeout, TR_CLOCK_TICK);
111 	}
112 
113 	if (time_left == -1)
114 		cmn_err(CE_WARN, "Timeout waiting for door calls to complete");
115 
116 	if (vscan_door_handle) {
117 		door_ki_rele(vscan_door_handle);
118 		vscan_door_handle = NULL;
119 	}
120 
121 	mutex_exit(&vscan_door_mutex);
122 }
123 
124 
125 /*
126  * vscan_door_scan_file
127  *
128  * Returns: result returned in door response or VS_STATUS_ERROR
129  */
130 int
131 vscan_door_scan_file(vs_scan_req_t *scan_req)
132 {
133 	int err;
134 	int i;
135 	door_arg_t arg;
136 	uint32_t result = 0;
137 
138 	if (!vscan_door_handle)
139 		return (VS_STATUS_ERROR);
140 
141 	mutex_enter(&vscan_door_mutex);
142 	vscan_door_call_count++;
143 	mutex_exit(&vscan_door_mutex);
144 
145 	arg.data_ptr = (char *)scan_req;
146 	arg.data_size = sizeof (vs_scan_req_t);
147 	arg.desc_ptr = NULL;
148 	arg.desc_num = 0;
149 	arg.rbuf = (char *)&result;
150 	arg.rsize = sizeof (uint32_t);
151 
152 	for (i = 0; i < VS_DOOR_RETRIES; ++i) {
153 		if ((err = door_ki_upcall_limited(vscan_door_handle, &arg,
154 		    NULL, SIZE_MAX, 0)) == 0)
155 			break;
156 
157 		if (err != EAGAIN && err != EINTR)
158 			break;
159 	}
160 
161 	if (err != 0) {
162 		cmn_err(CE_WARN, "Internal communication error (%d)"
163 		    "- failed to send scan request to vscand", err);
164 		result = VS_STATUS_ERROR;
165 	}
166 
167 	mutex_enter(&vscan_door_mutex);
168 	vscan_door_call_count--;
169 	cv_signal(&vscan_door_cv);
170 	mutex_exit(&vscan_door_mutex);
171 
172 	return (result);
173 }
174