1 /* 2 * CAM request queue management definitions. 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 * $Id$ 29 */ 30 31 #ifndef _CAM_CAM_QUEUE_H 32 #define _CAM_CAM_QUEUE_H 1 33 34 #ifdef KERNEL 35 36 #include <sys/queue.h> 37 38 /* 39 * This structure implements a heap based priority queue. The queue 40 * assumes that the objects stored in it begin with a cam_qentry 41 * structure holding the priority information used to sort the objects. 42 * This structure is opaque to clients (outside of the XPT layer) to allow 43 * the implementation to change without affecting them. 44 */ 45 struct camq { 46 cam_pinfo **queue_array; 47 int array_size; 48 int entries; 49 u_int32_t generation; 50 u_int32_t qfrozen_cnt; 51 }; 52 53 TAILQ_HEAD(ccb_hdr_list, ccb_hdr); 54 55 struct cam_ccbq { 56 struct camq queue; 57 int devq_openings; 58 int dev_openings; 59 int dev_active; 60 int held; 61 struct ccb_hdr_list active_ccbs; 62 }; 63 64 struct cam_ed; 65 66 struct cam_devq { 67 struct camq alloc_queue; 68 struct camq send_queue; 69 struct cam_ed *active_dev; 70 int alloc_openings; 71 int alloc_active; 72 int send_openings; 73 int send_active; 74 }; 75 76 77 struct cam_devq *cam_devq_alloc(int devices, int openings); 78 79 int cam_devq_init(struct cam_devq *devq, int devices, 80 int openings); 81 82 void cam_devq_free(struct cam_devq *devq); 83 84 u_int32_t cam_devq_resize(struct cam_devq *camq, int openings); 85 86 /* 87 * Allocate a cam_ccb_queue structure and initialize it. 88 */ 89 struct cam_ccbq *cam_ccbq_alloc(int openings); 90 91 u_int32_t cam_ccbq_resize(struct cam_ccbq *ccbq, int devices); 92 93 int cam_ccbq_init(struct cam_ccbq *ccbq, int openings); 94 95 void cam_ccbq_free(struct cam_ccbq *ccbq); 96 97 void cam_ccbq_fini(struct cam_ccbq *ccbq); 98 99 void cam_ccbq_regen(struct cam_ccbq *ccbq); 100 101 /* 102 * Allocate and initialize a cam_queue structure. 103 */ 104 struct camq *camq_alloc(int size); 105 106 /* 107 * Resize a cam queue 108 */ 109 u_int32_t camq_resize(struct camq *queue, int new_size); 110 111 /* 112 * Initialize a camq structure. Return 0 on success, 1 on failure. 113 */ 114 int camq_init(struct camq *camq, int size); 115 116 /* 117 * Free a cam_queue structure. This should only be called if a controller 118 * driver failes somehow during its attach routine or is unloaded and has 119 * obtained a cam_queue structure. 120 */ 121 void camq_free(struct camq *queue); 122 123 /* 124 * Finialize any internal storage or state of a cam_queue. 125 */ 126 void camq_fini(struct camq *queue); 127 128 /* 129 * cam_queue_insert: Given a CAM queue with at least one open spot, 130 * insert the new entry maintaining order. 131 */ 132 void camq_insert(struct camq *queue, cam_pinfo *new_entry); 133 134 /* 135 * camq_remove: Remove and arbitrary entry from the queue maintaining 136 * queue order. 137 */ 138 cam_pinfo *camq_remove(struct camq *queue, int index); 139 140 /* 141 * camq_change_priority: Raise or lower the priority of an entry 142 * maintaining queue order. 143 */ 144 void camq_change_priority(struct camq *queue, int index, 145 u_int32_t new_priority); 146 147 void camq_regen(struct camq *queue); 148 149 static __inline int 150 cam_ccbq_pending_ccb_count(struct cam_ccbq *ccbq); 151 152 static __inline void 153 cam_ccbq_take_opening(struct cam_ccbq *ccbq); 154 155 static __inline void 156 cam_ccbq_insert_ccb(struct cam_ccbq *ccbq, union ccb *new_ccb); 157 158 static __inline void 159 cam_ccbq_remove_ccb(struct cam_ccbq *ccbq, union ccb *ccb); 160 161 static __inline union ccb * 162 cam_ccbq_peek_ccb(struct cam_ccbq *ccbq, int index); 163 164 static __inline void 165 cam_ccbq_send_ccb(struct cam_ccbq *queue, union ccb *send_ccb); 166 167 static __inline void 168 cam_ccbq_ccb_done(struct cam_ccbq *ccbq, union ccb *done_ccb); 169 170 static __inline void 171 cam_ccbq_release_opening(struct cam_ccbq *ccbq); 172 173 174 static __inline int 175 cam_ccbq_pending_ccb_count(struct cam_ccbq *ccbq) 176 { 177 return (ccbq->queue.entries); 178 } 179 180 static __inline void 181 cam_ccbq_take_opening(struct cam_ccbq *ccbq) 182 { 183 ccbq->devq_openings--; 184 ccbq->held++; 185 } 186 187 static __inline void 188 cam_ccbq_insert_ccb(struct cam_ccbq *ccbq, union ccb *new_ccb) 189 { 190 ccbq->held--; 191 camq_insert(&ccbq->queue, &new_ccb->ccb_h.pinfo); 192 } 193 194 static __inline void 195 cam_ccbq_remove_ccb(struct cam_ccbq *ccbq, union ccb *ccb) 196 { 197 camq_remove(&ccbq->queue, ccb->ccb_h.pinfo.index); 198 } 199 200 static __inline union ccb * 201 cam_ccbq_peek_ccb(struct cam_ccbq *ccbq, int index) 202 { 203 return((union ccb *)ccbq->queue.queue_array[index]); 204 } 205 206 static __inline void 207 cam_ccbq_send_ccb(struct cam_ccbq *ccbq, union ccb *send_ccb) 208 { 209 210 TAILQ_INSERT_TAIL(&ccbq->active_ccbs, 211 &(send_ccb->ccb_h), 212 xpt_links.tqe); 213 send_ccb->ccb_h.pinfo.index = CAM_ACTIVE_INDEX; 214 ccbq->dev_active++; 215 ccbq->dev_openings--; 216 } 217 218 static __inline void 219 cam_ccbq_ccb_done(struct cam_ccbq *ccbq, union ccb *done_ccb) 220 { 221 TAILQ_REMOVE(&ccbq->active_ccbs, &done_ccb->ccb_h, 222 xpt_links.tqe); 223 ccbq->dev_active--; 224 ccbq->dev_openings++; 225 ccbq->held++; 226 } 227 228 static __inline void 229 cam_ccbq_release_opening(struct cam_ccbq *ccbq) 230 { 231 ccbq->held--; 232 ccbq->devq_openings++; 233 } 234 235 #endif /* KERNEL */ 236 #endif /* _CAM_CAM_QUEUE_H */ 237