cam_sim.c revision 186320 
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
29#include <sys/cdefs.h>
30__FBSDID("$FreeBSD: head/sys/cam/cam_sim.c 186320 2008-12-19 14:33:29Z trasz $");
31
32#include <sys/param.h>
33#include <sys/systm.h>
34#include <sys/malloc.h>
35#include <sys/kernel.h>
36#include <sys/lock.h>
37#include <sys/mutex.h>
38
39#include <cam/cam.h>
40#include <cam/cam_ccb.h>
41#include <cam/cam_sim.h>
42#include <cam/cam_queue.h>
43
44#define CAM_PATH_ANY (u_int32_t)-1
45
46MALLOC_DEFINE(M_CAMSIM, "CAM SIM", "CAM SIM buffers");
47
48struct cam_devq *
49cam_simq_alloc(u_int32_t max_sim_transactions)
50{
51	return (cam_devq_alloc(/*size*/0, max_sim_transactions));
52}
53
54void
55cam_simq_free(struct cam_devq *devq)
56{
57	cam_devq_free(devq);
58}
59
60struct cam_sim *
61cam_sim_alloc(sim_action_func sim_action, sim_poll_func sim_poll,
62	      const char *sim_name, void *softc, u_int32_t unit,
63	      struct mtx *mtx, int max_dev_transactions,
64	      int max_tagged_dev_transactions, struct cam_devq *queue)
65{
66	struct cam_sim *sim;
67
68	if (mtx == NULL)
69		return (NULL);
70
71	sim = (struct cam_sim *)malloc(sizeof(struct cam_sim),
72	    M_CAMSIM, M_NOWAIT);
73
74	if (sim == NULL)
75		return (NULL);
76
77	sim->sim_action = sim_action;
78	sim->sim_poll = sim_poll;
79	sim->sim_name = sim_name;
80	sim->softc = softc;
81	sim->path_id = CAM_PATH_ANY;
82	sim->unit_number = unit;
83	sim->bus_id = 0;	/* set in xpt_bus_register */
84	sim->max_tagged_dev_openings = max_tagged_dev_transactions;
85	sim->max_dev_openings = max_dev_transactions;
86	sim->flags = 0;
87	sim->refcount = 1;
88	sim->devq = queue;
89	sim->mtx = mtx;
90	if (mtx == &Giant) {
91		sim->flags |= 0;
92		callout_init(&sim->callout, 0);
93	} else {
94		sim->flags |= CAM_SIM_MPSAFE;
95		callout_init(&sim->callout, 1);
96	}
97
98	SLIST_INIT(&sim->ccb_freeq);
99	TAILQ_INIT(&sim->sim_doneq);
100
101	return (sim);
102}
103
104void
105cam_sim_free(struct cam_sim *sim, int free_devq)
106{
107	int error;
108
109	sim->refcount--;
110	if (sim->refcount > 0) {
111		error = msleep(sim, sim->mtx, PRIBIO, "simfree", 0);
112		KASSERT(error == 0, ("invalid error value for msleep(9)"));
113	}
114
115	KASSERT(sim->refcount == 0, ("sim->refcount == 0"));
116
117	if (free_devq)
118		cam_simq_free(sim->devq);
119	free(sim, M_CAMSIM);
120}
121
122void
123cam_sim_release(struct cam_sim *sim)
124{
125	KASSERT(sim->refcount >= 1, ("sim->refcount >= 1"));
126	mtx_assert(sim->mtx, MA_OWNED);
127
128	sim->refcount--;
129	if (sim->refcount == 0)
130		wakeup(sim);
131}
132
133void
134cam_sim_hold(struct cam_sim *sim)
135{
136	KASSERT(sim->refcount >= 1, ("sim->refcount >= 1"));
137	mtx_assert(sim->mtx, MA_OWNED);
138
139	sim->refcount++;
140}
141
142void
143cam_sim_set_path(struct cam_sim *sim, u_int32_t path_id)
144{
145	sim->path_id = path_id;
146}
147