cam_queue.h revision 139743
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: head/sys/cam/cam_queue.h 139743 2005-01-05 22:34:37Z imp $ 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 */ 45struct 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 53TAILQ_HEAD(ccb_hdr_tailq, ccb_hdr); 54LIST_HEAD(ccb_hdr_list, ccb_hdr); 55SLIST_HEAD(ccb_hdr_slist, ccb_hdr); 56 57struct cam_ccbq { 58 struct camq queue; 59 int devq_openings; 60 int dev_openings; 61 int dev_active; 62 int held; 63 struct ccb_hdr_tailq active_ccbs; 64}; 65 66struct cam_ed; 67 68struct cam_devq { 69 struct camq alloc_queue; 70 struct camq send_queue; 71 struct cam_ed *active_dev; 72 int alloc_openings; 73 int alloc_active; 74 int send_openings; 75 int send_active; 76}; 77 78 79struct cam_devq *cam_devq_alloc(int devices, int openings); 80 81int cam_devq_init(struct cam_devq *devq, int devices, 82 int openings); 83 84void cam_devq_free(struct cam_devq *devq); 85 86u_int32_t cam_devq_resize(struct cam_devq *camq, int openings); 87 88/* 89 * Allocate a cam_ccb_queue structure and initialize it. 90 */ 91struct cam_ccbq *cam_ccbq_alloc(int openings); 92 93u_int32_t cam_ccbq_resize(struct cam_ccbq *ccbq, int devices); 94 95int cam_ccbq_init(struct cam_ccbq *ccbq, int openings); 96 97void cam_ccbq_free(struct cam_ccbq *ccbq); 98 99void cam_ccbq_fini(struct cam_ccbq *ccbq); 100 101/* 102 * Allocate and initialize a cam_queue structure. 103 */ 104struct camq *camq_alloc(int size); 105 106/* 107 * Resize a cam queue 108 */ 109u_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 */ 114int 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 */ 121void camq_free(struct camq *queue); 122 123/* 124 * Finialize any internal storage or state of a cam_queue. 125 */ 126void 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 */ 132void 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 */ 138cam_pinfo *camq_remove(struct camq *queue, int index); 139#define CAMQ_HEAD 1 /* Head of queue index */ 140 141/* Index the first element in the heap */ 142#define CAMQ_GET_HEAD(camq) ((camq)->queue_array[CAMQ_HEAD]) 143 144/* 145 * camq_change_priority: Raise or lower the priority of an entry 146 * maintaining queue order. 147 */ 148void camq_change_priority(struct camq *queue, int index, 149 u_int32_t new_priority); 150 151static __inline int 152cam_ccbq_pending_ccb_count(struct cam_ccbq *ccbq); 153 154static __inline void 155cam_ccbq_take_opening(struct cam_ccbq *ccbq); 156 157static __inline void 158cam_ccbq_insert_ccb(struct cam_ccbq *ccbq, union ccb *new_ccb); 159 160static __inline void 161cam_ccbq_remove_ccb(struct cam_ccbq *ccbq, union ccb *ccb); 162 163static __inline union ccb * 164cam_ccbq_peek_ccb(struct cam_ccbq *ccbq, int index); 165 166static __inline void 167cam_ccbq_send_ccb(struct cam_ccbq *queue, union ccb *send_ccb); 168 169static __inline void 170cam_ccbq_ccb_done(struct cam_ccbq *ccbq, union ccb *done_ccb); 171 172static __inline void 173cam_ccbq_release_opening(struct cam_ccbq *ccbq); 174 175 176static __inline int 177cam_ccbq_pending_ccb_count(struct cam_ccbq *ccbq) 178{ 179 return (ccbq->queue.entries); 180} 181 182static __inline void 183cam_ccbq_take_opening(struct cam_ccbq *ccbq) 184{ 185 ccbq->devq_openings--; 186 ccbq->held++; 187} 188 189static __inline void 190cam_ccbq_insert_ccb(struct cam_ccbq *ccbq, union ccb *new_ccb) 191{ 192 ccbq->held--; 193 camq_insert(&ccbq->queue, &new_ccb->ccb_h.pinfo); 194} 195 196static __inline void 197cam_ccbq_remove_ccb(struct cam_ccbq *ccbq, union ccb *ccb) 198{ 199 camq_remove(&ccbq->queue, ccb->ccb_h.pinfo.index); 200} 201 202static __inline union ccb * 203cam_ccbq_peek_ccb(struct cam_ccbq *ccbq, int index) 204{ 205 return((union ccb *)ccbq->queue.queue_array[index]); 206} 207 208static __inline void 209cam_ccbq_send_ccb(struct cam_ccbq *ccbq, union ccb *send_ccb) 210{ 211 212 TAILQ_INSERT_TAIL(&ccbq->active_ccbs, 213 &(send_ccb->ccb_h), 214 xpt_links.tqe); 215 send_ccb->ccb_h.pinfo.index = CAM_ACTIVE_INDEX; 216 ccbq->dev_active++; 217 ccbq->dev_openings--; 218} 219 220static __inline void 221cam_ccbq_ccb_done(struct cam_ccbq *ccbq, union ccb *done_ccb) 222{ 223 TAILQ_REMOVE(&ccbq->active_ccbs, &done_ccb->ccb_h, 224 xpt_links.tqe); 225 ccbq->dev_active--; 226 ccbq->dev_openings++; 227 ccbq->held++; 228} 229 230static __inline void 231cam_ccbq_release_opening(struct cam_ccbq *ccbq) 232{ 233 ccbq->held--; 234 ccbq->devq_openings++; 235} 236 237#endif /* _KERNEL */ 238#endif /* _CAM_CAM_QUEUE_H */ 239