xref: /dragonfly/sys/bus/cam/cam_sim.c (revision e1acdbad)
1 /*
2  * Common functions for SCSI Interface Modules (SIMs).
3  *
4  * Copyright (c) 1997 Justin T. Gibbs.
5  * All rights reserved.
6  *
7  * Redistribution and use in source and binary forms, with or without
8  * modification, are permitted provided that the following conditions
9  * are met:
10  * 1. Redistributions of source code must retain the above copyright
11  *    notice, this list of conditions, and the following disclaimer,
12  *    without modification, immediately at the beginning of the file.
13  * 2. The name of the author may not be used to endorse or promote products
14  *    derived from this software without specific prior written permission.
15  *
16  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
17  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
18  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
19  * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE FOR
20  * ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
21  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
22  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
23  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
24  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
25  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
26  * SUCH DAMAGE.
27  *
28  * $FreeBSD: src/sys/cam/cam_sim.c,v 1.3 1999/08/28 00:40:42 peter Exp $
29  * $DragonFly: src/sys/bus/cam/cam_sim.c,v 1.7 2004/09/17 02:20:53 joerg Exp $
30  */
31 
32 #include <sys/param.h>
33 #include <sys/systm.h>
34 #include <sys/malloc.h>
35 
36 #include "cam.h"
37 #include "cam_ccb.h"
38 #include "cam_sim.h"
39 #include "cam_queue.h"
40 
41 #define CAM_PATH_ANY (u_int32_t)-1
42 
43 struct cam_devq *
44 cam_simq_alloc(u_int32_t max_sim_transactions)
45 {
46 	return (cam_devq_alloc(/*size*/0, max_sim_transactions));
47 }
48 
49 void
50 cam_simq_release(struct cam_devq *devq)
51 {
52 	cam_devq_release(devq);
53 }
54 
55 /*
56  * cam_sim_alloc() may potentially be called from an interrupt (?) but
57  * unexpected things happen to the system if malloc() returns NULL so we
58  * use M_INTWAIT anyway.
59  */
60 struct cam_sim *
61 cam_sim_alloc(sim_action_func sim_action, sim_poll_func sim_poll,
62 	      const char *sim_name, void *softc, u_int32_t unit,
63 	      int max_dev_transactions,
64 	      int max_tagged_dev_transactions, struct cam_devq *queue)
65 {
66 	struct cam_sim *sim;
67 
68 	/*
69 	 * XXX ahd was limited to 256 instead of 512 for unknown reasons,
70 	 * move that to a global limit here.  We may be able to remove this
71 	 * code, needs testing.
72 	 */
73 	if (max_dev_transactions > 256)
74 		max_dev_transactions = 256;
75 	if (max_tagged_dev_transactions > 256)
76 		max_tagged_dev_transactions = 256;
77 
78 	/*
79 	 * Allocate a simq or use the supplied (possibly shared) simq.
80 	 */
81 	if (queue == NULL)
82 		queue = cam_simq_alloc(max_tagged_dev_transactions);
83 	else
84 		cam_devq_reference(queue);
85 
86 	sim = malloc(sizeof(struct cam_sim), M_DEVBUF, M_INTWAIT | M_ZERO);
87 	sim->sim_action = sim_action;
88 	sim->sim_poll = sim_poll;
89 	sim->sim_name = sim_name;
90 	sim->softc = softc;
91 	sim->path_id = CAM_PATH_ANY;
92 	sim->unit_number = unit;
93 	sim->bus_id = 0;	/* set in xpt_bus_register */
94 	sim->max_tagged_dev_openings = max_tagged_dev_transactions;
95 	sim->max_dev_openings = max_dev_transactions;
96 	sim->flags = 0;
97 	sim->refcount = 1;
98 	callout_init(&sim->c_handle);
99 	sim->devq = queue;
100 
101 	return (sim);
102 }
103 
104 void
105 cam_sim_free(struct cam_sim *sim)
106 {
107 	cam_sim_release(sim, CAM_SIM_DEVQ | CAM_SIM_SOFTC);
108 }
109 
110 void
111 cam_sim_release(struct cam_sim *sim, int flags)
112 {
113 	if (flags & CAM_SIM_SOFTC)
114 		sim->softc = NULL;
115 	if (flags & CAM_SIM_DEVQ) {
116 		cam_simq_release(sim->devq);
117 		sim->devq = NULL;
118 	}
119 	if (sim->refcount == 1) {
120 		sim->refcount = 0;
121 		free(sim, M_DEVBUF);
122 	} else {
123 		--sim->refcount;
124 	}
125 }
126 
127 void
128 cam_sim_set_path(struct cam_sim *sim, u_int32_t path_id)
129 {
130 	sim->path_id = path_id;
131 }
132