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 (c) 2002-2003, Network Appliance, Inc. All rights reserved.
24  */
25 
26 /*
27  * Copyright 2008 Sun Microsystems, Inc.  All rights reserved.
28  * Use is subject to license terms.
29  */
30 
31 /*
32  *
33  * MODULE: dapl_evd_dto_callback.c
34  *
35  * PURPOSE: implements DTO callbacks from verbs
36  *
37  * $Id: dapl_evd_dto_callb.c,v 1.17 2003/07/30 18:13:38 hobie16 Exp $
38  */
39 
40 #include "dapl.h"
41 #include "dapl_evd_util.h"
42 #include "dapl_cno_util.h"
43 #include "dapl_cookie.h"
44 #include "dapl_adapter_util.h"
45 
46 /*
47  * dapl_evd_dto_callback
48  *
49  * Input:
50  * 	hca_handle_in,
51  * 	cq_handle_in,
52  *      user_context_cq_p
53  *
54  * Output:
55  *	none
56  *
57  * This is invoked for both DTO and MW bind completions. Strictly
58  * speaking it is an event callback rather than just a DTO callback.
59  *
60  */
61 
62 void
dapl_evd_dto_callback(IN ib_hca_handle_t hca_handle,IN ib_cq_handle_t cq_handle,IN void * user_context)63 dapl_evd_dto_callback(
64     IN ib_hca_handle_t 	hca_handle,
65     IN ib_cq_handle_t 	cq_handle,
66     IN void		*user_context)
67 {
68 	DAPL_EVD	*evd_ptr;
69 	DAT_RETURN	dat_status;
70 	DAPL_EVD_STATE	state;
71 
72 	dapl_dbg_log(DAPL_DBG_TYPE_CALLBACK,
73 	    "dapl_evd_dto_callback(%p, %p, %p)\n",
74 	    hca_handle,
75 	    cq_handle,
76 	    user_context);
77 
78 	evd_ptr = (DAPL_EVD *) user_context;
79 
80 	dapl_os_assert(hca_handle ==
81 	    evd_ptr->header.owner_ia->hca_ptr->ib_hca_handle);
82 	dapl_os_assert(evd_ptr->ib_cq_handle == cq_handle);
83 	dapl_os_assert(evd_ptr->header.magic == DAPL_MAGIC_EVD);
84 
85 	/* Read once.  */
86 	state = *(volatile DAPL_EVD_STATE *) &evd_ptr->evd_state;
87 
88 	dapl_dbg_log(DAPL_DBG_TYPE_EVD,
89 	    "-- dapl_evd_dto_callback: CQ %p, state %x\n",
90 	    (void *)evd_ptr->ib_cq_handle,
91 	    state);
92 
93 	/*
94 	 * This function does not dequeue from the CQ; only the consumer
95 	 * can do that. Instead, it wakes up waiters if any exist.
96 	 * It rearms the completion only if completions should always occur
97 	 * (specifically if a CNO is associated with the EVD and the
98 	 * EVD is enabled.
99 	 */
100 
101 	if (state == DAPL_EVD_STATE_WAITED) {
102 		/*
103 		 * If we could, it would be best to avoid this wakeup
104 		 * (and the context switch) unless the number of events/CQs
105 		 * waiting for the waiter was its threshold.  We don't
106 		 * currently have the ability to determine that without
107 		 * dequeueing the events, and we can't do that for
108 		 * synchronization reasons (racing with the waiter waking
109 		 * up and dequeuing, sparked by other callbacks).
110 		 */
111 
112 		/*
113 		 * We don't need to worry about taking the lock for the
114 		 * wakeup because wakeups are sticky.
115 		 */
116 		(void) dapl_os_wait_object_wakeup(&evd_ptr->wait_object);
117 	} else if (state == DAPL_EVD_STATE_OPEN) {
118 		DAPL_CNO *cno = evd_ptr->cno_ptr;
119 		if (evd_ptr->evd_enabled && (evd_ptr->cno_ptr != NULL)) {
120 			/*
121 			 * Re-enable callback, *then* trigger.
122 			 * This guarantees we won't miss any events.
123 			 */
124 			dat_status = DAPL_NOTIFY(evd_ptr)(
125 			    evd_ptr->ib_cq_handle, IB_NOTIFY_ON_NEXT_COMP, 0);
126 
127 			if (DAT_SUCCESS != dat_status) {
128 				(void) dapls_evd_post_async_error_event(
129 				    evd_ptr->header.owner_ia->async_error_evd,
130 				    DAT_ASYNC_ERROR_PROVIDER_INTERNAL_ERROR,
131 				    (DAT_IA_HANDLE)evd_ptr->header.owner_ia);
132 			}
133 
134 			dapl_cno_trigger(cno, evd_ptr);
135 		}
136 	}
137 	dapl_dbg_log(DAPL_DBG_TYPE_RTN, "dapl_evd_dto_callback() returns\n");
138 }
139 
140 /*
141  * Local variables:
142  *  c-indent-level: 4
143  *  c-basic-offset: 4
144  *  tab-width: 8
145  * End:
146  */
147