1139743Simp/*- 239212Sgibbs * CAM request queue management definitions. 339212Sgibbs * 439212Sgibbs * Copyright (c) 1997 Justin T. Gibbs. 539212Sgibbs * All rights reserved. 639212Sgibbs * 739212Sgibbs * Redistribution and use in source and binary forms, with or without 839212Sgibbs * modification, are permitted provided that the following conditions 939212Sgibbs * are met: 1039212Sgibbs * 1. Redistributions of source code must retain the above copyright 1139212Sgibbs * notice, this list of conditions, and the following disclaimer, 1239212Sgibbs * without modification, immediately at the beginning of the file. 1339212Sgibbs * 2. The name of the author may not be used to endorse or promote products 1439212Sgibbs * derived from this software without specific prior written permission. 1539212Sgibbs * 1639212Sgibbs * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 1739212Sgibbs * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 1839212Sgibbs * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 1939212Sgibbs * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE FOR 2039212Sgibbs * ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 2139212Sgibbs * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 2239212Sgibbs * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 2339212Sgibbs * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 2439212Sgibbs * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 2539212Sgibbs * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 2639212Sgibbs * SUCH DAMAGE. 2739212Sgibbs * 2850477Speter * $FreeBSD: stable/11/sys/cam/cam_queue.h 308352 2016-11-05 20:23:18Z markj $ 2939212Sgibbs */ 3039212Sgibbs 3139212Sgibbs#ifndef _CAM_CAM_QUEUE_H 3239212Sgibbs#define _CAM_CAM_QUEUE_H 1 3339212Sgibbs 3455206Speter#ifdef _KERNEL 3539212Sgibbs 36256843Smav#include <sys/lock.h> 37256843Smav#include <sys/mutex.h> 3839212Sgibbs#include <sys/queue.h> 39203108Smav#include <cam/cam.h> 4039212Sgibbs 4139212Sgibbs/* 4239212Sgibbs * This structure implements a heap based priority queue. The queue 4339212Sgibbs * assumes that the objects stored in it begin with a cam_qentry 4439212Sgibbs * structure holding the priority information used to sort the objects. 4539212Sgibbs * This structure is opaque to clients (outside of the XPT layer) to allow 4639212Sgibbs * the implementation to change without affecting them. 4739212Sgibbs */ 4839212Sgibbsstruct camq { 4939212Sgibbs cam_pinfo **queue_array; 5039212Sgibbs int array_size; 5139212Sgibbs int entries; 5239212Sgibbs u_int32_t generation; 53249466Smav u_int32_t qfrozen_cnt; 5439212Sgibbs}; 5539212Sgibbs 5660938SjakeTAILQ_HEAD(ccb_hdr_tailq, ccb_hdr); 5760938SjakeLIST_HEAD(ccb_hdr_list, ccb_hdr); 5860938SjakeSLIST_HEAD(ccb_hdr_slist, ccb_hdr); 5939212Sgibbs 6039212Sgibbsstruct cam_ccbq { 6139212Sgibbs struct camq queue; 62253958Smav struct ccb_hdr_tailq queue_extra_head; 63253958Smav int queue_extra_entries; 64256843Smav int total_openings; 65271588Smav int allocated; 66249466Smav int dev_openings; 6739212Sgibbs int dev_active; 6839212Sgibbs}; 6939212Sgibbs 7039212Sgibbsstruct cam_ed; 7139212Sgibbs 7239212Sgibbsstruct cam_devq { 73256843Smav struct mtx send_mtx; 74256843Smav struct camq send_queue; 75256843Smav int send_openings; 76256843Smav int send_active; 7739212Sgibbs}; 7839212Sgibbs 7939212Sgibbs 8039212Sgibbsstruct cam_devq *cam_devq_alloc(int devices, int openings); 8139212Sgibbs 8239212Sgibbsint cam_devq_init(struct cam_devq *devq, int devices, 8339212Sgibbs int openings); 8439212Sgibbs 8539212Sgibbsvoid cam_devq_free(struct cam_devq *devq); 8639212Sgibbs 8739212Sgibbsu_int32_t cam_devq_resize(struct cam_devq *camq, int openings); 8839212Sgibbs 8939212Sgibbs/* 9039212Sgibbs * Allocate a cam_ccb_queue structure and initialize it. 9139212Sgibbs */ 9239212Sgibbsstruct cam_ccbq *cam_ccbq_alloc(int openings); 9339212Sgibbs 9439212Sgibbsu_int32_t cam_ccbq_resize(struct cam_ccbq *ccbq, int devices); 9539212Sgibbs 9639212Sgibbsint cam_ccbq_init(struct cam_ccbq *ccbq, int openings); 9739212Sgibbs 9839212Sgibbsvoid cam_ccbq_free(struct cam_ccbq *ccbq); 9939212Sgibbs 100198377Smavvoid cam_ccbq_fini(struct cam_ccbq *ccbq); 101198377Smav 10239212Sgibbs/* 10339212Sgibbs * Allocate and initialize a cam_queue structure. 10439212Sgibbs */ 10539212Sgibbsstruct camq *camq_alloc(int size); 10639212Sgibbs 10739212Sgibbs/* 10839212Sgibbs * Resize a cam queue 10939212Sgibbs */ 11039212Sgibbsu_int32_t camq_resize(struct camq *queue, int new_size); 11139212Sgibbs 11239212Sgibbs/* 11339212Sgibbs * Initialize a camq structure. Return 0 on success, 1 on failure. 11439212Sgibbs */ 11539212Sgibbsint camq_init(struct camq *camq, int size); 11639212Sgibbs 11739212Sgibbs/* 11839212Sgibbs * Free a cam_queue structure. This should only be called if a controller 11939212Sgibbs * driver failes somehow during its attach routine or is unloaded and has 12039212Sgibbs * obtained a cam_queue structure. 12139212Sgibbs */ 12239212Sgibbsvoid camq_free(struct camq *queue); 12339212Sgibbs 12439212Sgibbs/* 12539212Sgibbs * Finialize any internal storage or state of a cam_queue. 12639212Sgibbs */ 12739212Sgibbsvoid camq_fini(struct camq *queue); 12839212Sgibbs 12939212Sgibbs/* 13039212Sgibbs * cam_queue_insert: Given a CAM queue with at least one open spot, 13139212Sgibbs * insert the new entry maintaining order. 13239212Sgibbs */ 13339212Sgibbsvoid camq_insert(struct camq *queue, cam_pinfo *new_entry); 13439212Sgibbs 13539212Sgibbs/* 13639212Sgibbs * camq_remove: Remove and arbitrary entry from the queue maintaining 13739212Sgibbs * queue order. 13839212Sgibbs */ 13939212Sgibbscam_pinfo *camq_remove(struct camq *queue, int index); 14045844Sgibbs#define CAMQ_HEAD 1 /* Head of queue index */ 14139212Sgibbs 14245844Sgibbs/* Index the first element in the heap */ 14345844Sgibbs#define CAMQ_GET_HEAD(camq) ((camq)->queue_array[CAMQ_HEAD]) 14445844Sgibbs 145203108Smav/* Get the first element priority. */ 146203108Smav#define CAMQ_GET_PRIO(camq) (((camq)->entries > 0) ? \ 147203108Smav ((camq)->queue_array[CAMQ_HEAD]->priority) : 0) 148203108Smav 14939212Sgibbs/* 15039212Sgibbs * camq_change_priority: Raise or lower the priority of an entry 15139212Sgibbs * maintaining queue order. 15239212Sgibbs */ 15339212Sgibbsvoid camq_change_priority(struct camq *queue, int index, 15439212Sgibbs u_int32_t new_priority); 15539212Sgibbs 15639212Sgibbsstatic __inline int 15739212Sgibbscam_ccbq_pending_ccb_count(struct cam_ccbq *ccbq); 15839212Sgibbs 15939212Sgibbsstatic __inline void 16039212Sgibbscam_ccbq_take_opening(struct cam_ccbq *ccbq); 16139212Sgibbs 162249481Smavstatic __inline void 16339212Sgibbscam_ccbq_insert_ccb(struct cam_ccbq *ccbq, union ccb *new_ccb); 16439212Sgibbs 165249481Smavstatic __inline void 16639212Sgibbscam_ccbq_remove_ccb(struct cam_ccbq *ccbq, union ccb *ccb); 16739212Sgibbs 16839212Sgibbsstatic __inline union ccb * 16939212Sgibbscam_ccbq_peek_ccb(struct cam_ccbq *ccbq, int index); 17039212Sgibbs 17139212Sgibbsstatic __inline void 17239212Sgibbscam_ccbq_send_ccb(struct cam_ccbq *queue, union ccb *send_ccb); 17339212Sgibbs 17439212Sgibbsstatic __inline void 17539212Sgibbscam_ccbq_ccb_done(struct cam_ccbq *ccbq, union ccb *done_ccb); 17639212Sgibbs 17739212Sgibbsstatic __inline void 17839212Sgibbscam_ccbq_release_opening(struct cam_ccbq *ccbq); 17939212Sgibbs 18039212Sgibbs 18139212Sgibbsstatic __inline int 18239212Sgibbscam_ccbq_pending_ccb_count(struct cam_ccbq *ccbq) 18339212Sgibbs{ 184253958Smav return (ccbq->queue.entries + ccbq->queue_extra_entries); 18539212Sgibbs} 18639212Sgibbs 18739212Sgibbsstatic __inline void 18839212Sgibbscam_ccbq_take_opening(struct cam_ccbq *ccbq) 18939212Sgibbs{ 190271588Smav 191271588Smav ccbq->allocated++; 19239212Sgibbs} 19339212Sgibbs 194249481Smavstatic __inline void 19539212Sgibbscam_ccbq_insert_ccb(struct cam_ccbq *ccbq, union ccb *new_ccb) 19639212Sgibbs{ 197253958Smav struct ccb_hdr *old_ccb; 198253958Smav struct camq *queue = &ccbq->queue; 199253958Smav 200308352Smarkj KASSERT((new_ccb->ccb_h.func_code & XPT_FC_QUEUED) != 0 && 201308352Smarkj (new_ccb->ccb_h.func_code & XPT_FC_USER_CCB) == 0, 202308352Smarkj ("%s: Cannot queue ccb %p func_code %#x", __func__, new_ccb, 203308352Smarkj new_ccb->ccb_h.func_code)); 204308352Smarkj 205253958Smav /* 206253958Smav * If queue is already full, try to resize. 207253958Smav * If resize fail, push CCB with lowest priority out to the TAILQ. 208253958Smav */ 209253958Smav if (queue->entries == queue->array_size && 210253958Smav camq_resize(&ccbq->queue, queue->array_size * 2) != CAM_REQ_CMP) { 211253958Smav old_ccb = (struct ccb_hdr *)camq_remove(queue, queue->entries); 212253958Smav TAILQ_INSERT_HEAD(&ccbq->queue_extra_head, old_ccb, 213253958Smav xpt_links.tqe); 214253958Smav old_ccb->pinfo.index = CAM_EXTRAQ_INDEX; 215253958Smav ccbq->queue_extra_entries++; 216253958Smav } 217253958Smav 218253958Smav camq_insert(queue, &new_ccb->ccb_h.pinfo); 21939212Sgibbs} 22039212Sgibbs 221249481Smavstatic __inline void 22239212Sgibbscam_ccbq_remove_ccb(struct cam_ccbq *ccbq, union ccb *ccb) 22339212Sgibbs{ 224253958Smav struct ccb_hdr *cccb, *bccb; 225253958Smav struct camq *queue = &ccbq->queue; 226308352Smarkj cam_pinfo *removed_entry __unused; 227253958Smav 228253958Smav /* If the CCB is on the TAILQ, remove it from there. */ 229253958Smav if (ccb->ccb_h.pinfo.index == CAM_EXTRAQ_INDEX) { 230253958Smav TAILQ_REMOVE(&ccbq->queue_extra_head, &ccb->ccb_h, 231253958Smav xpt_links.tqe); 232253958Smav ccb->ccb_h.pinfo.index = CAM_UNQUEUED_INDEX; 233253958Smav ccbq->queue_extra_entries--; 234253958Smav return; 235253958Smav } 236253958Smav 237308352Smarkj removed_entry = camq_remove(queue, ccb->ccb_h.pinfo.index); 238308352Smarkj KASSERT(removed_entry == &ccb->ccb_h.pinfo, 239308352Smarkj ("%s: Removed wrong entry from queue (%p != %p)", __func__, 240308352Smarkj removed_entry, &ccb->ccb_h.pinfo)); 241253958Smav 242253958Smav /* 243253958Smav * If there are some CCBs on TAILQ, find the best one and move it 244253958Smav * to the emptied space in the queue. 245253958Smav */ 246253958Smav bccb = TAILQ_FIRST(&ccbq->queue_extra_head); 247253958Smav if (bccb == NULL) 248253958Smav return; 249253958Smav TAILQ_FOREACH(cccb, &ccbq->queue_extra_head, xpt_links.tqe) { 250253958Smav if (bccb->pinfo.priority > cccb->pinfo.priority || 251253958Smav (bccb->pinfo.priority == cccb->pinfo.priority && 252253958Smav GENERATIONCMP(bccb->pinfo.generation, >, 253253958Smav cccb->pinfo.generation))) 254253958Smav bccb = cccb; 255253958Smav } 256253958Smav TAILQ_REMOVE(&ccbq->queue_extra_head, bccb, xpt_links.tqe); 257253958Smav ccbq->queue_extra_entries--; 258253958Smav camq_insert(queue, &bccb->pinfo); 25939212Sgibbs} 26039212Sgibbs 26139212Sgibbsstatic __inline union ccb * 26239212Sgibbscam_ccbq_peek_ccb(struct cam_ccbq *ccbq, int index) 26339212Sgibbs{ 26439212Sgibbs return((union ccb *)ccbq->queue.queue_array[index]); 26539212Sgibbs} 26639212Sgibbs 26739212Sgibbsstatic __inline void 26839212Sgibbscam_ccbq_send_ccb(struct cam_ccbq *ccbq, union ccb *send_ccb) 26939212Sgibbs{ 27039212Sgibbs 27139212Sgibbs send_ccb->ccb_h.pinfo.index = CAM_ACTIVE_INDEX; 27239212Sgibbs ccbq->dev_active++; 273271588Smav ccbq->dev_openings--; 27439212Sgibbs} 27539212Sgibbs 27639212Sgibbsstatic __inline void 27739212Sgibbscam_ccbq_ccb_done(struct cam_ccbq *ccbq, union ccb *done_ccb) 27839212Sgibbs{ 279199281Smav 28039212Sgibbs ccbq->dev_active--; 281271588Smav ccbq->dev_openings++; 28239212Sgibbs} 28339212Sgibbs 28439212Sgibbsstatic __inline void 28539212Sgibbscam_ccbq_release_opening(struct cam_ccbq *ccbq) 28639212Sgibbs{ 287271588Smav 288271588Smav ccbq->allocated--; 28939212Sgibbs} 29039212Sgibbs 29155206Speter#endif /* _KERNEL */ 29239212Sgibbs#endif /* _CAM_CAM_QUEUE_H */ 293