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 * $FreeBSD: src/sys/cam/cam_queue.h,v 1.6 1999/12/29 04:54:26 peter Exp $ 29 * $DragonFly: src/sys/bus/cam/cam_queue.h,v 1.3 2004/03/15 01:10:30 dillon Exp $ 30 */ 31 32 #ifndef _CAM_CAM_QUEUE_H 33 #define _CAM_CAM_QUEUE_H 1 34 35 #ifdef _KERNEL 36 37 #include <sys/queue.h> 38 39 /* 40 * This structure implements a heap based priority queue. The queue 41 * assumes that the objects stored in it begin with a cam_qentry 42 * structure holding the priority information used to sort the objects. 43 * This structure is opaque to clients (outside of the XPT layer) to allow 44 * the implementation to change without affecting them. 45 */ 46 struct camq { 47 cam_pinfo **queue_array; 48 int array_size; 49 int entries; 50 u_int32_t generation; 51 u_int32_t qfrozen_cnt; 52 }; 53 54 TAILQ_HEAD(ccb_hdr_tailq, ccb_hdr); 55 LIST_HEAD(ccb_hdr_list, ccb_hdr); 56 SLIST_HEAD(ccb_hdr_slist, ccb_hdr); 57 58 struct cam_ccbq { 59 struct camq queue; 60 int devq_openings; 61 int dev_openings; 62 int dev_active; 63 int held; 64 struct ccb_hdr_tailq active_ccbs; 65 }; 66 67 struct cam_ed; 68 69 struct cam_devq { 70 struct camq alloc_queue; 71 struct camq send_queue; 72 struct cam_ed *active_dev; 73 int alloc_openings; 74 int alloc_active; 75 int send_openings; 76 int send_active; 77 int refcount; 78 }; 79 80 81 struct cam_devq *cam_devq_alloc(int devices, int openings); 82 83 int cam_devq_init(struct cam_devq *devq, int devices, 84 int openings); 85 void cam_devq_reference(struct cam_devq *devq); 86 void cam_devq_release(struct cam_devq *devq); 87 u_int32_t cam_devq_resize(struct cam_devq *camq, int openings); 88 89 /* 90 * Allocate a cam_ccb_queue structure and initialize it. 91 */ 92 struct cam_ccbq *cam_ccbq_alloc(int openings); 93 94 u_int32_t cam_ccbq_resize(struct cam_ccbq *ccbq, int devices); 95 96 int cam_ccbq_init(struct cam_ccbq *ccbq, int openings); 97 98 void cam_ccbq_free(struct cam_ccbq *ccbq); 99 100 void cam_ccbq_fini(struct cam_ccbq *ccbq); 101 102 /* 103 * Allocate and initialize a cam_queue structure. 104 */ 105 struct camq *camq_alloc(int size); 106 107 /* 108 * Resize a cam queue 109 */ 110 u_int32_t camq_resize(struct camq *queue, int new_size); 111 112 /* 113 * Initialize a camq structure. Return 0 on success, 1 on failure. 114 */ 115 int camq_init(struct camq *camq, int size); 116 117 /* 118 * Free a cam_queue structure. This should only be called if a controller 119 * driver failes somehow during its attach routine or is unloaded and has 120 * obtained a cam_queue structure. 121 */ 122 void camq_free(struct camq *queue); 123 124 /* 125 * Finialize any internal storage or state of a cam_queue. 126 */ 127 void camq_fini(struct camq *queue); 128 129 /* 130 * cam_queue_insert: Given a CAM queue with at least one open spot, 131 * insert the new entry maintaining order. 132 */ 133 void camq_insert(struct camq *queue, cam_pinfo *new_entry); 134 135 /* 136 * camq_remove: Remove and arbitrary entry from the queue maintaining 137 * queue order. 138 */ 139 cam_pinfo *camq_remove(struct camq *queue, int index); 140 #define CAMQ_HEAD 1 /* Head of queue index */ 141 142 /* Index the first element in the heap */ 143 #define CAMQ_GET_HEAD(camq) ((camq)->queue_array[CAMQ_HEAD]) 144 145 /* 146 * camq_change_priority: Raise or lower the priority of an entry 147 * maintaining queue order. 148 */ 149 void camq_change_priority(struct camq *queue, int index, 150 u_int32_t new_priority); 151 152 static __inline int 153 cam_ccbq_pending_ccb_count(struct cam_ccbq *ccbq); 154 155 static __inline void 156 cam_ccbq_take_opening(struct cam_ccbq *ccbq); 157 158 static __inline void 159 cam_ccbq_insert_ccb(struct cam_ccbq *ccbq, union ccb *new_ccb); 160 161 static __inline void 162 cam_ccbq_remove_ccb(struct cam_ccbq *ccbq, union ccb *ccb); 163 164 static __inline union ccb * 165 cam_ccbq_peek_ccb(struct cam_ccbq *ccbq, int index); 166 167 static __inline void 168 cam_ccbq_send_ccb(struct cam_ccbq *queue, union ccb *send_ccb); 169 170 static __inline void 171 cam_ccbq_ccb_done(struct cam_ccbq *ccbq, union ccb *done_ccb); 172 173 static __inline void 174 cam_ccbq_release_opening(struct cam_ccbq *ccbq); 175 176 177 static __inline int 178 cam_ccbq_pending_ccb_count(struct cam_ccbq *ccbq) 179 { 180 return (ccbq->queue.entries); 181 } 182 183 static __inline void 184 cam_ccbq_take_opening(struct cam_ccbq *ccbq) 185 { 186 ccbq->devq_openings--; 187 ccbq->held++; 188 } 189 190 static __inline void 191 cam_ccbq_insert_ccb(struct cam_ccbq *ccbq, union ccb *new_ccb) 192 { 193 ccbq->held--; 194 camq_insert(&ccbq->queue, &new_ccb->ccb_h.pinfo); 195 } 196 197 static __inline void 198 cam_ccbq_remove_ccb(struct cam_ccbq *ccbq, union ccb *ccb) 199 { 200 camq_remove(&ccbq->queue, ccb->ccb_h.pinfo.index); 201 } 202 203 static __inline union ccb * 204 cam_ccbq_peek_ccb(struct cam_ccbq *ccbq, int index) 205 { 206 return((union ccb *)ccbq->queue.queue_array[index]); 207 } 208 209 static __inline void 210 cam_ccbq_send_ccb(struct cam_ccbq *ccbq, union ccb *send_ccb) 211 { 212 213 TAILQ_INSERT_TAIL(&ccbq->active_ccbs, 214 &(send_ccb->ccb_h), 215 xpt_links.tqe); 216 send_ccb->ccb_h.pinfo.index = CAM_ACTIVE_INDEX; 217 ccbq->dev_active++; 218 ccbq->dev_openings--; 219 } 220 221 static __inline void 222 cam_ccbq_ccb_done(struct cam_ccbq *ccbq, union ccb *done_ccb) 223 { 224 TAILQ_REMOVE(&ccbq->active_ccbs, &done_ccb->ccb_h, 225 xpt_links.tqe); 226 ccbq->dev_active--; 227 ccbq->dev_openings++; 228 ccbq->held++; 229 } 230 231 static __inline void 232 cam_ccbq_release_opening(struct cam_ccbq *ccbq) 233 { 234 ccbq->held--; 235 ccbq->devq_openings++; 236 } 237 238 #endif /* _KERNEL */ 239 #endif /* _CAM_CAM_QUEUE_H */ 240