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 #pragma ident	"%Z%%M%	%I%	%E% SMI"
28 
29 /*
30  * support functions for hba drivers to handle scsi reset notifications.
31  */
32 
33 #include <sys/scsi/scsi.h>
34 #include <sys/scsi/impl/scsi_reset_notify.h>
35 
36 /*
37  * routine for reset notification setup.
38  * The function is entered without adapter driver mutex being held.
39  */
40 
41 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)42 scsi_hba_reset_notify_setup(struct scsi_address *ap, int flag,
43 	void (*callback)(caddr_t), caddr_t arg, kmutex_t *mutex,
44 	struct scsi_reset_notify_entry **listp)
45 {
46 	struct scsi_reset_notify_entry	*p, *beforep;
47 	int				rval = DDI_FAILURE;
48 
49 	mutex_enter(mutex);
50 	p = *listp;
51 	beforep = NULL;
52 	while (p) {
53 		if (p->ap == ap)
54 			break;		/* An entry exist for this target */
55 		beforep = p;
56 		p = p->next;
57 	}
58 
59 	if ((flag & SCSI_RESET_CANCEL) && (p != NULL)) {
60 		if (beforep == NULL) {
61 			*listp = p->next;
62 		} else {
63 			beforep->next = p->next;
64 		}
65 		kmem_free(p, sizeof (struct scsi_reset_notify_entry));
66 		rval = DDI_SUCCESS;
67 
68 	} else if ((flag & SCSI_RESET_NOTIFY) && (p == NULL)) {
69 		p = kmem_zalloc(sizeof (struct scsi_reset_notify_entry),
70 		    KM_SLEEP);
71 		p->ap = ap;
72 		p->callback = callback;
73 		p->arg = arg;
74 		p->next = *listp;
75 		*listp = p;
76 		rval = DDI_SUCCESS;
77 	}
78 	mutex_exit(mutex);
79 	return (rval);
80 }
81 
82 /*
83  * routine to deallocate the callback list
84  */
85 void
scsi_hba_reset_notify_tear_down(struct scsi_reset_notify_entry * listp)86 scsi_hba_reset_notify_tear_down(struct scsi_reset_notify_entry *listp)
87 {
88 	struct scsi_reset_notify_entry	*p, *next;
89 
90 	p = listp;
91 	while (p) {
92 		next = p->next;
93 		kmem_free(p, sizeof (struct scsi_reset_notify_entry));
94 		p = next;
95 	}
96 }
97 
98 
99 /*
100  * routine to perform the notification callbacks after a reset.
101  * The function is entered with adapter driver mutex being held.
102  */
103 void
scsi_hba_reset_notify_callback(kmutex_t * mutex,struct scsi_reset_notify_entry ** listp)104 scsi_hba_reset_notify_callback(kmutex_t *mutex,
105 	struct scsi_reset_notify_entry **listp)
106 {
107 	int	i, count;
108 	struct	scsi_reset_notify_entry	*p;
109 	struct	notify_entry {
110 		void	(*callback)(caddr_t);
111 		caddr_t	arg;
112 	} *list;
113 
114 	if ((p = *listp) == NULL)
115 		return;
116 
117 	count = 0;
118 	while (p != NULL) {
119 		count++;
120 		p = p->next;
121 	}
122 
123 	list = kmem_alloc(count * sizeof (struct notify_entry), KM_NOSLEEP);
124 	if (list == NULL) {
125 		cmn_err(CE_WARN, "scsi_reset_notify: kmem_alloc failed");
126 		return;
127 	}
128 
129 	for (i = 0, p = *listp; i < count; i++, p = p->next) {
130 		list[i].callback = p->callback;
131 		list[i].arg = p->arg;
132 	}
133 
134 	mutex_exit(mutex);
135 	for (i = 0; i < count; i++) {
136 		if (list[i].callback != NULL)
137 			(void) (*list[i].callback)(list[i].arg);
138 	}
139 	kmem_free(list, count * sizeof (struct notify_entry));
140 	mutex_enter(mutex);
141 }
142