sys/cam/cam_sim.c

   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("$FreeBSD$");
  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
  47 static MALLOC_DEFINE(M_CAMSIM, "CAM SIM", "CAM SIM buffers");
  48
  49 struct cam_devq *
  50 cam_simq_alloc(u_int32_t max_sim_transactions)
  51 {
  52         return (cam_devq_alloc(/*size*/0, max_sim_transactions));
  53 }
  54
  55 void
  56 cam_simq_free(struct cam_devq *devq)
  57 {
  58         cam_devq_free(devq);
  59 }
  60
  61 struct cam_sim *
  62 cam_sim_alloc(sim_action_func sim_action, sim_poll_func sim_poll,
  63               const char *sim_name, void *softc, u_int32_t unit,
  64               struct mtx *mtx, int max_dev_transactions,
  65               int max_tagged_dev_transactions, struct cam_devq *queue)
  66 {
  67         struct cam_sim *sim;
  68
  69         if (mtx == NULL)
  70                 return (NULL);
  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
 101 void
 102 cam_sim_free(struct cam_sim *sim, int free_devq)
 103 {
 104         int error;
 105
 106         mtx_assert(sim->mtx, MA_OWNED);
 107         sim->refcount--;
 108         if (sim->refcount > 0) {
 109                 error = msleep(sim, sim->mtx, PRIBIO, "simfree", 0);
 110                 KASSERT(error == 0, ("invalid error value for msleep(9)"));
 111         }
 112
 113         KASSERT(sim->refcount == 0, ("sim->refcount == 0"));
 114
 115         if (free_devq)
 116                 cam_simq_free(sim->devq);
 117         free(sim, M_CAMSIM);
 118 }
 119
 120 void
 121 cam_sim_release(struct cam_sim *sim)
 122 {
 123         int lock;
 124
 125         lock = (mtx_owned(sim->mtx) == 0);
 126         if (lock)
 127                 CAM_SIM_LOCK(sim);
 128         KASSERT(sim->refcount >= 1, ("sim->refcount >= 1"));
 129         sim->refcount--;
 130         if (sim->refcount == 0)
 131                 wakeup(sim);
 132         if (lock)
 133                 CAM_SIM_UNLOCK(sim);
 134 }
 135
 136 void
 137 cam_sim_hold(struct cam_sim *sim)
 138 {
 139         int lock;
 140
 141         lock = (mtx_owned(sim->mtx) == 0);
 142         if (lock)
 143                 CAM_SIM_LOCK(sim);
 144         KASSERT(sim->refcount >= 1, ("sim->refcount >= 1"));
 145         sim->refcount++;
 146         if (lock)
 147                 CAM_SIM_UNLOCK(sim);
 148 }
 149
 150 void
 151 cam_sim_set_path(struct cam_sim *sim, u_int32_t path_id)
 152 {
 153         sim->path_id = path_id;
 154 }