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 (c) 1998 by Sun Microsystems, Inc.
24  * All rights reserved.
25  */
26 
27 /*
28  * support functions for hba drivers to handle scsi reset notifications.
29  */
30 
31 #include <sys/scsi/scsi.h>
32 #include <sys/scsi/impl/scsi_reset_notify.h>
33 
34 /*
35  * routine for reset notification setup.
36  * The function is entered without adapter driver mutex being held.
37  */
38 
39 int
scsi_hba_reset_notify_setup(struct scsi_address * ap,int flag,void (* callback)(caddr_t),caddr_t arg,kmutex_t * mutex,struct scsi_reset_notify_entry ** listp)40 scsi_hba_reset_notify_setup(struct scsi_address *ap, int flag,
41 	void (*callback)(caddr_t), caddr_t arg, kmutex_t *mutex,
42 	struct scsi_reset_notify_entry **listp)
43 {
44 	struct scsi_reset_notify_entry	*p, *beforep;
45 	int				rval = DDI_FAILURE;
46 
47 	mutex_enter(mutex);
48 	p = *listp;
49 	beforep = NULL;
50 	while (p) {
51 		if (p->ap == ap)
52 			break;		/* An entry exist for this target */
53 		beforep = p;
54 		p = p->next;
55 	}
56 
57 	if ((flag & SCSI_RESET_CANCEL) && (p != NULL)) {
58 		if (beforep == NULL) {
59 			*listp = p->next;
60 		} else {
61 			beforep->next = p->next;
62 		}
63 		kmem_free(p, sizeof (struct scsi_reset_notify_entry));
64 		rval = DDI_SUCCESS;
65 
66 	} else if ((flag & SCSI_RESET_NOTIFY) && (p == NULL)) {
67 		p = kmem_zalloc(sizeof (struct scsi_reset_notify_entry),
68 		    KM_SLEEP);
69 		p->ap = ap;
70 		p->callback = callback;
71 		p->arg = arg;
72 		p->next = *listp;
73 		*listp = p;
74 		rval = DDI_SUCCESS;
75 	}
76 	mutex_exit(mutex);
77 	return (rval);
78 }
79 
80 /*
81  * routine to deallocate the callback list
82  */
83 void
scsi_hba_reset_notify_tear_down(struct scsi_reset_notify_entry * listp)84 scsi_hba_reset_notify_tear_down(struct scsi_reset_notify_entry *listp)
85 {
86 	struct scsi_reset_notify_entry	*p, *next;
87 
88 	p = listp;
89 	while (p) {
90 		next = p->next;
91 		kmem_free(p, sizeof (struct scsi_reset_notify_entry));
92 		p = next;
93 	}
94 }
95 
96 
97 /*
98  * routine to perform the notification callbacks after a reset.
99  * The function is entered with adapter driver mutex being held.
100  */
101 void
scsi_hba_reset_notify_callback(kmutex_t * mutex,struct scsi_reset_notify_entry ** listp)102 scsi_hba_reset_notify_callback(kmutex_t *mutex,
103 	struct scsi_reset_notify_entry **listp)
104 {
105 	int	i, count;
106 	struct	scsi_reset_notify_entry	*p;
107 	struct	notify_entry {
108 		void	(*callback)(caddr_t);
109 		caddr_t	arg;
110 	} *list;
111 
112 	if ((p = *listp) == NULL)
113 		return;
114 
115 	count = 0;
116 	while (p != NULL) {
117 		count++;
118 		p = p->next;
119 	}
120 
121 	list = kmem_alloc(count * sizeof (struct notify_entry), KM_NOSLEEP);
122 	if (list == NULL) {
123 		cmn_err(CE_WARN, "scsi_reset_notify: kmem_alloc failed");
124 		return;
125 	}
126 
127 	for (i = 0, p = *listp; i < count; i++, p = p->next) {
128 		list[i].callback = p->callback;
129 		list[i].arg = p->arg;
130 	}
131 
132 	mutex_exit(mutex);
133 	for (i = 0; i < count; i++) {
134 		if (list[i].callback != NULL)
135 			(void) (*list[i].callback)(list[i].arg);
136 	}
137 	kmem_free(list, count * sizeof (struct notify_entry));
138 	mutex_enter(mutex);
139 }
140