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: stable/11/sys/cam/cam_sim.c 316498 2017-04-04 17:59:10Z mav $");
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#include <cam/cam_xpt.h>
44
45#define CAM_PATH_ANY (u_int32_t)-1
46
47static MALLOC_DEFINE(M_CAMSIM, "CAM SIM", "CAM SIM buffers");
48
49static struct mtx cam_sim_free_mtx;
50MTX_SYSINIT(cam_sim_free_init, &cam_sim_free_mtx, "CAM SIM free lock", MTX_DEF);
51
52struct cam_devq *
53cam_simq_alloc(u_int32_t max_sim_transactions)
54{
55	return (cam_devq_alloc(/*size*/0, max_sim_transactions));
56}
57
58void
59cam_simq_free(struct cam_devq *devq)
60{
61	cam_devq_free(devq);
62}
63
64struct cam_sim *
65cam_sim_alloc(sim_action_func sim_action, sim_poll_func sim_poll,
66	      const char *sim_name, void *softc, u_int32_t unit,
67	      struct mtx *mtx, int max_dev_transactions,
68	      int max_tagged_dev_transactions, struct cam_devq *queue)
69{
70	struct cam_sim *sim;
71
72	sim = (struct cam_sim *)malloc(sizeof(struct cam_sim),
73	    M_CAMSIM, M_ZERO | M_NOWAIT);
74
75	if (sim == NULL)
76		return (NULL);
77
78	sim->sim_action = sim_action;
79	sim->sim_poll = sim_poll;
80	sim->sim_name = sim_name;
81	sim->softc = softc;
82	sim->path_id = CAM_PATH_ANY;
83	sim->unit_number = unit;
84	sim->bus_id = 0;	/* set in xpt_bus_register */
85	sim->max_tagged_dev_openings = max_tagged_dev_transactions;
86	sim->max_dev_openings = max_dev_transactions;
87	sim->flags = 0;
88	sim->refcount = 1;
89	sim->devq = queue;
90	sim->mtx = mtx;
91	if (mtx == &Giant) {
92		sim->flags |= 0;
93		callout_init(&sim->callout, 0);
94	} else {
95		sim->flags |= CAM_SIM_MPSAFE;
96		callout_init(&sim->callout, 1);
97	}
98	return (sim);
99}
100
101void
102cam_sim_free(struct cam_sim *sim, int free_devq)
103{
104	struct mtx *mtx = sim->mtx;
105	int error;
106
107	if (mtx) {
108		mtx_assert(mtx, MA_OWNED);
109	} else {
110		mtx = &cam_sim_free_mtx;
111		mtx_lock(mtx);
112	}
113	sim->refcount--;
114	if (sim->refcount > 0) {
115		error = msleep(sim, mtx, PRIBIO, "simfree", 0);
116		KASSERT(error == 0, ("invalid error value for msleep(9)"));
117	}
118	KASSERT(sim->refcount == 0, ("sim->refcount == 0"));
119	if (sim->mtx == NULL)
120		mtx_unlock(mtx);
121
122	if (free_devq)
123		cam_simq_free(sim->devq);
124	free(sim, M_CAMSIM);
125}
126
127void
128cam_sim_release(struct cam_sim *sim)
129{
130	struct mtx *mtx = sim->mtx;
131
132	if (mtx) {
133		if (!mtx_owned(mtx))
134			mtx_lock(mtx);
135		else
136			mtx = NULL;
137	} else {
138		mtx = &cam_sim_free_mtx;
139		mtx_lock(mtx);
140	}
141	KASSERT(sim->refcount >= 1, ("sim->refcount >= 1"));
142	sim->refcount--;
143	if (sim->refcount == 0)
144		wakeup(sim);
145	if (mtx)
146		mtx_unlock(mtx);
147}
148
149void
150cam_sim_hold(struct cam_sim *sim)
151{
152	struct mtx *mtx = sim->mtx;
153
154	if (mtx) {
155		if (!mtx_owned(mtx))
156			mtx_lock(mtx);
157		else
158			mtx = NULL;
159	} else {
160		mtx = &cam_sim_free_mtx;
161		mtx_lock(mtx);
162	}
163	KASSERT(sim->refcount >= 1, ("sim->refcount >= 1"));
164	sim->refcount++;
165	if (mtx)
166		mtx_unlock(mtx);
167}
168
169void
170cam_sim_set_path(struct cam_sim *sim, u_int32_t path_id)
171{
172	sim->path_id = path_id;
173}
174