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
31 #ifndef _CAM_CAM_QUEUE_H
32 #define _CAM_CAM_QUEUE_H 1
36 #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[CAM_RL_VALUES];
54 TAILQ_HEAD(ccb_hdr_tailq, ccb_hdr);
55 LIST_HEAD(ccb_hdr_list, ccb_hdr);
56 SLIST_HEAD(ccb_hdr_slist, ccb_hdr);
69 struct camq alloc_queue;
70 struct camq send_queue;
71 struct cam_ed *active_dev;
79 struct cam_devq *cam_devq_alloc(int devices, int openings);
81 int cam_devq_init(struct cam_devq *devq, int devices,
84 void cam_devq_free(struct cam_devq *devq);
86 u_int32_t cam_devq_resize(struct cam_devq *camq, int openings);
89 * Allocate a cam_ccb_queue structure and initialize it.
91 struct cam_ccbq *cam_ccbq_alloc(int openings);
93 u_int32_t cam_ccbq_resize(struct cam_ccbq *ccbq, int devices);
95 int cam_ccbq_init(struct cam_ccbq *ccbq, int openings);
97 void cam_ccbq_free(struct cam_ccbq *ccbq);
99 void cam_ccbq_fini(struct cam_ccbq *ccbq);
102 * Allocate and initialize a cam_queue structure.
104 struct camq *camq_alloc(int size);
109 u_int32_t camq_resize(struct camq *queue, int new_size);
112 * Initialize a camq structure. Return 0 on success, 1 on failure.
114 int camq_init(struct camq *camq, int size);
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.
121 void camq_free(struct camq *queue);
124 * Finialize any internal storage or state of a cam_queue.
126 void camq_fini(struct camq *queue);
129 * cam_queue_insert: Given a CAM queue with at least one open spot,
130 * insert the new entry maintaining order.
132 void camq_insert(struct camq *queue, cam_pinfo *new_entry);
135 * camq_remove: Remove and arbitrary entry from the queue maintaining
138 cam_pinfo *camq_remove(struct camq *queue, int index);
139 #define CAMQ_HEAD 1 /* Head of queue index */
141 /* Index the first element in the heap */
142 #define CAMQ_GET_HEAD(camq) ((camq)->queue_array[CAMQ_HEAD])
144 /* Get the first element priority. */
145 #define CAMQ_GET_PRIO(camq) (((camq)->entries > 0) ? \
146 ((camq)->queue_array[CAMQ_HEAD]->priority) : 0)
149 * camq_change_priority: Raise or lower the priority of an entry
150 * maintaining queue order.
152 void camq_change_priority(struct camq *queue, int index,
153 u_int32_t new_priority);
156 cam_ccbq_pending_ccb_count(struct cam_ccbq *ccbq);
159 cam_ccbq_take_opening(struct cam_ccbq *ccbq);
162 cam_ccbq_insert_ccb(struct cam_ccbq *ccbq, union ccb *new_ccb);
165 cam_ccbq_remove_ccb(struct cam_ccbq *ccbq, union ccb *ccb);
167 static __inline union ccb *
168 cam_ccbq_peek_ccb(struct cam_ccbq *ccbq, int index);
171 cam_ccbq_send_ccb(struct cam_ccbq *queue, union ccb *send_ccb);
174 cam_ccbq_ccb_done(struct cam_ccbq *ccbq, union ccb *done_ccb);
177 cam_ccbq_release_opening(struct cam_ccbq *ccbq);
181 cam_ccbq_pending_ccb_count(struct cam_ccbq *ccbq)
183 return (ccbq->queue.entries);
187 cam_ccbq_take_opening(struct cam_ccbq *ccbq)
189 ccbq->devq_openings--;
194 cam_ccbq_insert_ccb(struct cam_ccbq *ccbq, union ccb *new_ccb)
197 camq_insert(&ccbq->queue, &new_ccb->ccb_h.pinfo);
198 if (ccbq->queue.qfrozen_cnt[CAM_PRIORITY_TO_RL(
199 new_ccb->ccb_h.pinfo.priority)] > 0) {
200 ccbq->devq_openings++;
208 cam_ccbq_remove_ccb(struct cam_ccbq *ccbq, union ccb *ccb)
210 camq_remove(&ccbq->queue, ccb->ccb_h.pinfo.index);
211 if (ccbq->queue.qfrozen_cnt[CAM_PRIORITY_TO_RL(
212 ccb->ccb_h.pinfo.priority)] > 0) {
213 ccbq->devq_openings--;
220 static __inline union ccb *
221 cam_ccbq_peek_ccb(struct cam_ccbq *ccbq, int index)
223 return((union ccb *)ccbq->queue.queue_array[index]);
227 cam_ccbq_send_ccb(struct cam_ccbq *ccbq, union ccb *send_ccb)
230 send_ccb->ccb_h.pinfo.index = CAM_ACTIVE_INDEX;
232 ccbq->dev_openings--;
236 cam_ccbq_ccb_done(struct cam_ccbq *ccbq, union ccb *done_ccb)
240 ccbq->dev_openings++;
245 cam_ccbq_release_opening(struct cam_ccbq *ccbq)
248 ccbq->devq_openings++;
252 cam_ccbq_freeze(struct cam_ccbq *ccbq, cam_rl rl, u_int32_t cnt)
257 /* Find pevious run level. */
258 for (p = 0; p < CAM_RL_VALUES && ccbq->queue.qfrozen_cnt[p] == 0; p++);
259 /* Find new run level. */
261 /* Apply new run level. */
262 for (i = rl; i < CAM_RL_VALUES; i++)
263 ccbq->queue.qfrozen_cnt[i] += cnt;
264 /* Update ccbq statistics. */
267 for (i = CAMQ_HEAD; i <= ccbq->queue.entries; i++) {
269 CAM_PRIORITY_TO_RL(ccbq->queue.queue_array[i]->priority);
274 ccbq->devq_openings++;
282 cam_ccbq_release(struct cam_ccbq *ccbq, cam_rl rl, u_int32_t cnt)
287 /* Apply new run level. */
288 for (i = rl; i < CAM_RL_VALUES; i++)
289 ccbq->queue.qfrozen_cnt[i] -= cnt;
290 /* Find new run level. */
291 for (n = 0; n < CAM_RL_VALUES && ccbq->queue.qfrozen_cnt[n] == 0; n++);
292 /* Find previous run level. */
294 /* Update ccbq statistics. */
297 for (i = CAMQ_HEAD; i <= ccbq->queue.entries; i++) {
299 CAM_PRIORITY_TO_RL(ccbq->queue.queue_array[i]->priority);
304 ccbq->devq_openings--;
311 static __inline u_int32_t
312 cam_ccbq_frozen(struct cam_ccbq *ccbq, cam_rl rl)
315 return (ccbq->queue.qfrozen_cnt[rl]);
318 static __inline u_int32_t
319 cam_ccbq_frozen_top(struct cam_ccbq *ccbq)
323 rl = CAM_PRIORITY_TO_RL(CAMQ_GET_PRIO(&ccbq->queue));
324 return (ccbq->queue.qfrozen_cnt[rl]);
328 #endif /* _CAM_CAM_QUEUE_H */