1 /*- 2 * Common functions for SCSI Interface Modules (SIMs). 3 * 4 * SPDX-License-Identifier: BSD-2-Clause-FreeBSD 5 * 6 * Copyright (c) 1997 Justin T. Gibbs. 7 * All rights reserved. 8 * 9 * Redistribution and use in source and binary forms, with or without 10 * modification, are permitted provided that the following conditions 11 * are met: 12 * 1. Redistributions of source code must retain the above copyright 13 * notice, this list of conditions, and the following disclaimer, 14 * without modification, immediately at the beginning of the file. 15 * 2. The name of the author may not be used to endorse or promote products 16 * derived from this software without specific prior written permission. 17 * 18 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 19 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 20 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 21 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE FOR 22 * ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 23 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 24 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 25 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 26 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 27 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 28 * SUCH DAMAGE. 29 */ 30 31 #include <sys/cdefs.h> 32 __FBSDID("$FreeBSD$"); 33 34 #include <sys/param.h> 35 #include <sys/systm.h> 36 #include <sys/malloc.h> 37 #include <sys/kernel.h> 38 #include <sys/lock.h> 39 #include <sys/mutex.h> 40 #include <sys/bus.h> 41 42 #include <cam/cam.h> 43 #include <cam/cam_ccb.h> 44 #include <cam/cam_sim.h> 45 #include <cam/cam_queue.h> 46 #include <cam/cam_xpt.h> 47 48 #define CAM_PATH_ANY (u_int32_t)-1 49 50 static MALLOC_DEFINE(M_CAMSIM, "CAM SIM", "CAM SIM buffers"); 51 52 static struct mtx cam_sim_free_mtx; 53 MTX_SYSINIT(cam_sim_free_init, &cam_sim_free_mtx, "CAM SIM free lock", MTX_DEF); 54 55 struct cam_devq * 56 cam_simq_alloc(u_int32_t max_sim_transactions) 57 { 58 return (cam_devq_alloc(/*size*/0, max_sim_transactions)); 59 } 60 61 void 62 cam_simq_free(struct cam_devq *devq) 63 { 64 cam_devq_free(devq); 65 } 66 67 struct cam_sim * 68 cam_sim_alloc(sim_action_func sim_action, sim_poll_func sim_poll, 69 const char *sim_name, void *softc, u_int32_t unit, 70 struct mtx *mtx, int max_dev_transactions, 71 int max_tagged_dev_transactions, struct cam_devq *queue) 72 { 73 struct cam_sim *sim; 74 75 sim = (struct cam_sim *)malloc(sizeof(struct cam_sim), 76 M_CAMSIM, M_ZERO | M_NOWAIT); 77 78 if (sim == NULL) 79 return (NULL); 80 81 sim->sim_action = sim_action; 82 sim->sim_poll = sim_poll; 83 sim->sim_name = sim_name; 84 sim->softc = softc; 85 sim->path_id = CAM_PATH_ANY; 86 sim->sim_dev = NULL; /* set only by cam_sim_alloc_dev */ 87 sim->unit_number = unit; 88 sim->bus_id = 0; /* set in xpt_bus_register */ 89 sim->max_tagged_dev_openings = max_tagged_dev_transactions; 90 sim->max_dev_openings = max_dev_transactions; 91 sim->flags = 0; 92 sim->refcount = 1; 93 sim->devq = queue; 94 sim->mtx = mtx; 95 if (mtx == &Giant) { 96 sim->flags |= 0; 97 callout_init(&sim->callout, 0); 98 } else { 99 sim->flags |= CAM_SIM_MPSAFE; 100 callout_init(&sim->callout, 1); 101 } 102 return (sim); 103 } 104 105 struct cam_sim * 106 cam_sim_alloc_dev(sim_action_func sim_action, sim_poll_func sim_poll, 107 const char *sim_name, void *softc, device_t dev, 108 struct mtx *mtx, int max_dev_transactions, 109 int max_tagged_dev_transactions, struct cam_devq *queue) 110 { 111 struct cam_sim *sim; 112 113 KASSERT(dev != NULL, ("%s: dev is null for sim_name %s softc %p\n", 114 __func__, sim_name, softc)); 115 116 sim = cam_sim_alloc(sim_action, sim_poll, sim_name, softc, 117 device_get_unit(dev), mtx, max_dev_transactions, 118 max_tagged_dev_transactions, queue); 119 if (sim != NULL) 120 sim->sim_dev = dev; 121 return (sim); 122 } 123 124 void 125 cam_sim_free(struct cam_sim *sim, int free_devq) 126 { 127 struct mtx *mtx; 128 int error; 129 130 if (sim->mtx == NULL) { 131 mtx = &cam_sim_free_mtx; 132 mtx_lock(mtx); 133 } else { 134 mtx = sim->mtx; 135 mtx_assert(mtx, MA_OWNED); 136 } 137 KASSERT(sim->refcount >= 1, ("sim->refcount >= 1")); 138 sim->refcount--; 139 if (sim->refcount > 0) { 140 error = msleep(sim, mtx, PRIBIO, "simfree", 0); 141 KASSERT(error == 0, ("invalid error value for msleep(9)")); 142 } 143 KASSERT(sim->refcount == 0, ("sim->refcount == 0")); 144 if (mtx == &cam_sim_free_mtx) /* sim->mtx == NULL */ 145 mtx_unlock(mtx); 146 147 if (free_devq) 148 cam_simq_free(sim->devq); 149 free(sim, M_CAMSIM); 150 } 151 152 void 153 cam_sim_release(struct cam_sim *sim) 154 { 155 struct mtx *mtx; 156 157 if (sim->mtx == NULL) 158 mtx = &cam_sim_free_mtx; 159 else if (!mtx_owned(sim->mtx)) 160 mtx = sim->mtx; 161 else 162 mtx = NULL; /* We hold the lock. */ 163 if (mtx) 164 mtx_lock(mtx); 165 KASSERT(sim->refcount >= 1, ("sim->refcount >= 1")); 166 sim->refcount--; 167 if (sim->refcount == 0) 168 wakeup(sim); 169 if (mtx) 170 mtx_unlock(mtx); 171 } 172 173 void 174 cam_sim_hold(struct cam_sim *sim) 175 { 176 struct mtx *mtx; 177 178 if (sim->mtx == NULL) 179 mtx = &cam_sim_free_mtx; 180 else if (!mtx_owned(sim->mtx)) 181 mtx = sim->mtx; 182 else 183 mtx = NULL; /* We hold the lock. */ 184 if (mtx) 185 mtx_lock(mtx); 186 KASSERT(sim->refcount >= 1, ("sim->refcount >= 1")); 187 sim->refcount++; 188 if (mtx) 189 mtx_unlock(mtx); 190 } 191 192 void 193 cam_sim_set_path(struct cam_sim *sim, u_int32_t path_id) 194 { 195 sim->path_id = path_id; 196 } 197