2 * CAM request queue management definitions.
4 * Copyright (c) 1997 Justin T. Gibbs.
7 * Redistribution and use in source and binary forms, with or without
8 * modification, are permitted provided that the following conditions
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.
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
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 $
32 #ifndef _CAM_CAM_QUEUE_H
33 #define _CAM_CAM_QUEUE_H 1
37 #include <sys/queue.h>
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.
47 cam_pinfo **queue_array;
51 u_int32_t qfrozen_cnt;
54 TAILQ_HEAD(ccb_hdr_tailq, ccb_hdr);
55 LIST_HEAD(ccb_hdr_list, ccb_hdr);
56 SLIST_HEAD(ccb_hdr_slist, ccb_hdr);
64 struct ccb_hdr_tailq active_ccbs;
70 struct camq alloc_queue;
71 struct camq send_queue;
72 struct cam_ed *active_dev;
81 struct cam_devq *cam_devq_alloc(int devices, int openings);
83 int cam_devq_init(struct cam_devq *devq, int devices,
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);
90 * Allocate a cam_ccb_queue structure and initialize it.
92 struct cam_ccbq *cam_ccbq_alloc(int openings);
94 u_int32_t cam_ccbq_resize(struct cam_ccbq *ccbq, int devices);
96 int cam_ccbq_init(struct cam_ccbq *ccbq, int openings);
98 void cam_ccbq_free(struct cam_ccbq *ccbq);
100 void cam_ccbq_fini(struct cam_ccbq *ccbq);
103 * Allocate and initialize a cam_queue structure.
105 struct camq *camq_alloc(int size);
110 u_int32_t camq_resize(struct camq *queue, int new_size);
113 * Initialize a camq structure. Return 0 on success, 1 on failure.
115 int camq_init(struct camq *camq, int size);
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.
122 void camq_free(struct camq *queue);
125 * Finialize any internal storage or state of a cam_queue.
127 void camq_fini(struct camq *queue);
130 * cam_queue_insert: Given a CAM queue with at least one open spot,
131 * insert the new entry maintaining order.
133 void camq_insert(struct camq *queue, cam_pinfo *new_entry);
136 * camq_remove: Remove and arbitrary entry from the queue maintaining
139 cam_pinfo *camq_remove(struct camq *queue, int index);
140 #define CAMQ_HEAD 1 /* Head of queue index */
142 /* Index the first element in the heap */
143 #define CAMQ_GET_HEAD(camq) ((camq)->queue_array[CAMQ_HEAD])
146 * camq_change_priority: Raise or lower the priority of an entry
147 * maintaining queue order.
149 void camq_change_priority(struct camq *queue, int index,
150 u_int32_t new_priority);
153 cam_ccbq_pending_ccb_count(struct cam_ccbq *ccbq);
156 cam_ccbq_take_opening(struct cam_ccbq *ccbq);
159 cam_ccbq_insert_ccb(struct cam_ccbq *ccbq, union ccb *new_ccb);
162 cam_ccbq_remove_ccb(struct cam_ccbq *ccbq, union ccb *ccb);
164 static __inline union ccb *
165 cam_ccbq_peek_ccb(struct cam_ccbq *ccbq, int index);
168 cam_ccbq_send_ccb(struct cam_ccbq *queue, union ccb *send_ccb);
171 cam_ccbq_ccb_done(struct cam_ccbq *ccbq, union ccb *done_ccb);
174 cam_ccbq_release_opening(struct cam_ccbq *ccbq);
178 cam_ccbq_pending_ccb_count(struct cam_ccbq *ccbq)
180 return (ccbq->queue.entries);
184 cam_ccbq_take_opening(struct cam_ccbq *ccbq)
186 ccbq->devq_openings--;
191 cam_ccbq_insert_ccb(struct cam_ccbq *ccbq, union ccb *new_ccb)
194 camq_insert(&ccbq->queue, &new_ccb->ccb_h.pinfo);
198 cam_ccbq_remove_ccb(struct cam_ccbq *ccbq, union ccb *ccb)
200 camq_remove(&ccbq->queue, ccb->ccb_h.pinfo.index);
203 static __inline union ccb *
204 cam_ccbq_peek_ccb(struct cam_ccbq *ccbq, int index)
206 return((union ccb *)ccbq->queue.queue_array[index]);
210 cam_ccbq_send_ccb(struct cam_ccbq *ccbq, union ccb *send_ccb)
213 TAILQ_INSERT_TAIL(&ccbq->active_ccbs,
216 send_ccb->ccb_h.pinfo.index = CAM_ACTIVE_INDEX;
218 ccbq->dev_openings--;
222 cam_ccbq_ccb_done(struct cam_ccbq *ccbq, union ccb *done_ccb)
224 TAILQ_REMOVE(&ccbq->active_ccbs, &done_ccb->ccb_h,
227 ccbq->dev_openings++;
232 cam_ccbq_release_opening(struct cam_ccbq *ccbq)
235 ccbq->devq_openings++;
239 #endif /* _CAM_CAM_QUEUE_H */