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 1.10 2007/12/01 22:21:17 pavalos Exp $ 30 */ 31 32 #include <sys/param.h> 33 #include <sys/systm.h> 34 #include <sys/malloc.h> 35 #include <sys/kernel.h> 36 37 #include "cam.h" 38 #include "cam_ccb.h" 39 #include "cam_sim.h" 40 #include "cam_queue.h" 41 #include "cam_xpt_sim.h" 42 43 #define CAM_PATH_ANY (u_int32_t)-1 44 45 MALLOC_DEFINE(M_CAMSIM, "CAM SIM", "CAM SIM buffers"); 46 47 struct cam_devq * 48 cam_simq_alloc(u_int32_t max_sim_transactions) 49 { 50 return (cam_devq_alloc(/*size*/0, max_sim_transactions)); 51 } 52 53 void 54 cam_simq_release(struct cam_devq *devq) 55 { 56 cam_devq_release(devq); 57 } 58 59 /* 60 * cam_sim_alloc() may potentially be called from an interrupt (?) but 61 * unexpected things happen to the system if malloc() returns NULL so we 62 * use M_INTWAIT anyway. 63 */ 64 struct cam_sim * 65 cam_sim_alloc(sim_action_func sim_action, sim_poll_func sim_poll, 66 const char *sim_name, void *softc, u_int32_t unit, 67 int max_dev_transactions, 68 int max_tagged_dev_transactions, struct cam_devq *queue) 69 { 70 struct cam_sim *sim; 71 72 /* 73 * XXX ahd was limited to 256 instead of 512 for unknown reasons, 74 * move that to a global limit here. We may be able to remove this 75 * code, needs testing. 76 */ 77 if (max_dev_transactions > 256) 78 max_dev_transactions = 256; 79 if (max_tagged_dev_transactions > 256) 80 max_tagged_dev_transactions = 256; 81 82 /* 83 * Allocate a simq or use the supplied (possibly shared) simq. 84 */ 85 if (queue == NULL) 86 queue = cam_simq_alloc(max_tagged_dev_transactions); 87 else 88 cam_devq_reference(queue); 89 90 sim = kmalloc(sizeof(struct cam_sim), M_CAMSIM, M_INTWAIT | M_ZERO); 91 sim->sim_action = sim_action; 92 sim->sim_poll = sim_poll; 93 sim->sim_name = sim_name; 94 sim->softc = softc; 95 sim->path_id = CAM_PATH_ANY; 96 sim->unit_number = unit; 97 sim->bus_id = 0; /* set in xpt_bus_register */ 98 sim->max_tagged_dev_openings = max_tagged_dev_transactions; 99 sim->max_dev_openings = max_dev_transactions; 100 sim->flags = 0; 101 sim->refcount = 1; 102 callout_init(&sim->c_handle); 103 sim->devq = queue; 104 105 return (sim); 106 } 107 108 static void deadsim_poll(struct cam_sim *sim); 109 static void deadsim_action(struct cam_sim *sim, union ccb *ccb); 110 111 void 112 cam_sim_free(struct cam_sim *sim) 113 { 114 sim->sim_action = deadsim_action; 115 sim->sim_poll = deadsim_poll; 116 cam_sim_release(sim, CAM_SIM_SOFTC); 117 } 118 119 /* 120 * Note: the devq is still used by individual peripherals even if the 121 * backend sim disappears, so do not destroy it until the sim itself 122 * is no longer needed. 123 */ 124 void 125 cam_sim_release(struct cam_sim *sim, int flags) 126 { 127 if (flags & CAM_SIM_SOFTC) 128 sim->softc = NULL; 129 if (sim->refcount == 1) { 130 if (sim->devq) { 131 cam_simq_release(sim->devq); 132 sim->devq = NULL; 133 } 134 sim->refcount = 0; 135 kfree(sim, M_CAMSIM); 136 } else { 137 --sim->refcount; 138 } 139 } 140 141 void 142 cam_sim_set_path(struct cam_sim *sim, u_int32_t path_id) 143 { 144 sim->path_id = path_id; 145 } 146 147 /* 148 * Dead sim poll and action functions. The backend to the sim has gone 149 * away, aka usb, scsi device, etc... deal with it. 150 */ 151 static void 152 deadsim_poll(struct cam_sim *sim) 153 { 154 /* empty */ 155 } 156 157 static void 158 deadsim_action(struct cam_sim *sim, union ccb *ccb) 159 { 160 ccb->ccb_h.status = CAM_TID_INVALID; 161 xpt_done(ccb); 162 } 163 164