/*- * CAM request queue management definitions. * * Copyright (c) 1997 Justin T. Gibbs. * All rights reserved. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * 1. Redistributions of source code must retain the above copyright * notice, this list of conditions, and the following disclaimer, * without modification, immediately at the beginning of the file. * 2. The name of the author may not be used to endorse or promote products * derived from this software without specific prior written permission. * * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE FOR * ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF * SUCH DAMAGE. * * $FreeBSD$ */ #ifndef _CAM_CAM_QUEUE_H #define _CAM_CAM_QUEUE_H 1 #ifdef _KERNEL #include <sys/lock.h> #include <sys/mutex.h> #include <sys/queue.h> #include <cam/cam.h> /* * This structure implements a heap based priority queue. The queue * assumes that the objects stored in it begin with a cam_qentry * structure holding the priority information used to sort the objects. * This structure is opaque to clients (outside of the XPT layer) to allow * the implementation to change without affecting them. */ struct camq { cam_pinfo **queue_array; int array_size; int entries; u_int32_t generation; u_int32_t qfrozen_cnt; }; TAILQ_HEAD(ccb_hdr_tailq, ccb_hdr); LIST_HEAD(ccb_hdr_list, ccb_hdr); SLIST_HEAD(ccb_hdr_slist, ccb_hdr); struct cam_ccbq { struct camq queue; struct ccb_hdr_tailq queue_extra_head; int queue_extra_entries; int total_openings; int allocated; int dev_openings; int dev_active; }; struct cam_ed; struct cam_devq { struct mtx send_mtx; struct camq send_queue; int send_openings; int send_active; }; struct cam_devq *cam_devq_alloc(int devices, int openings); int cam_devq_init(struct cam_devq *devq, int devices, int openings); void cam_devq_free(struct cam_devq *devq); u_int32_t cam_devq_resize(struct cam_devq *camq, int openings); /* * Allocate a cam_ccb_queue structure and initialize it. */ struct cam_ccbq *cam_ccbq_alloc(int openings); u_int32_t cam_ccbq_resize(struct cam_ccbq *ccbq, int devices); int cam_ccbq_init(struct cam_ccbq *ccbq, int openings); void cam_ccbq_free(struct cam_ccbq *ccbq); void cam_ccbq_fini(struct cam_ccbq *ccbq); /* * Allocate and initialize a cam_queue structure. */ struct camq *camq_alloc(int size); /* * Resize a cam queue */ u_int32_t camq_resize(struct camq *queue, int new_size); /* * Initialize a camq structure. Return 0 on success, 1 on failure. */ int camq_init(struct camq *camq, int size); /* * Free a cam_queue structure. This should only be called if a controller * driver failes somehow during its attach routine or is unloaded and has * obtained a cam_queue structure. */ void camq_free(struct camq *queue); /* * Finialize any internal storage or state of a cam_queue. */ void camq_fini(struct camq *queue); /* * cam_queue_insert: Given a CAM queue with at least one open spot, * insert the new entry maintaining order. */ void camq_insert(struct camq *queue, cam_pinfo *new_entry); /* * camq_remove: Remove and arbitrary entry from the queue maintaining * queue order. */ cam_pinfo *camq_remove(struct camq *queue, int index); #define CAMQ_HEAD 1 /* Head of queue index */ /* Index the first element in the heap */ #define CAMQ_GET_HEAD(camq) ((camq)->queue_array[CAMQ_HEAD]) /* Get the first element priority. */ #define CAMQ_GET_PRIO(camq) (((camq)->entries > 0) ? \ ((camq)->queue_array[CAMQ_HEAD]->priority) : 0) /* * camq_change_priority: Raise or lower the priority of an entry * maintaining queue order. */ void camq_change_priority(struct camq *queue, int index, u_int32_t new_priority); static __inline int cam_ccbq_pending_ccb_count(struct cam_ccbq *ccbq); static __inline void cam_ccbq_take_opening(struct cam_ccbq *ccbq); static __inline void cam_ccbq_insert_ccb(struct cam_ccbq *ccbq, union ccb *new_ccb); static __inline void cam_ccbq_remove_ccb(struct cam_ccbq *ccbq, union ccb *ccb); static __inline union ccb * cam_ccbq_peek_ccb(struct cam_ccbq *ccbq, int index); static __inline void cam_ccbq_send_ccb(struct cam_ccbq *queue, union ccb *send_ccb); static __inline void cam_ccbq_ccb_done(struct cam_ccbq *ccbq, union ccb *done_ccb); static __inline void cam_ccbq_release_opening(struct cam_ccbq *ccbq); static __inline int cam_ccbq_pending_ccb_count(struct cam_ccbq *ccbq) { return (ccbq->queue.entries + ccbq->queue_extra_entries); } static __inline void cam_ccbq_take_opening(struct cam_ccbq *ccbq) { ccbq->allocated++; } static __inline void cam_ccbq_insert_ccb(struct cam_ccbq *ccbq, union ccb *new_ccb) { struct ccb_hdr *old_ccb; struct camq *queue = &ccbq->queue; /* * If queue is already full, try to resize. * If resize fail, push CCB with lowest priority out to the TAILQ. */ if (queue->entries == queue->array_size && camq_resize(&ccbq->queue, queue->array_size * 2) != CAM_REQ_CMP) { old_ccb = (struct ccb_hdr *)camq_remove(queue, queue->entries); TAILQ_INSERT_HEAD(&ccbq->queue_extra_head, old_ccb, xpt_links.tqe); old_ccb->pinfo.index = CAM_EXTRAQ_INDEX; ccbq->queue_extra_entries++; } camq_insert(queue, &new_ccb->ccb_h.pinfo); } static __inline void cam_ccbq_remove_ccb(struct cam_ccbq *ccbq, union ccb *ccb) { struct ccb_hdr *cccb, *bccb; struct camq *queue = &ccbq->queue; /* If the CCB is on the TAILQ, remove it from there. */ if (ccb->ccb_h.pinfo.index == CAM_EXTRAQ_INDEX) { TAILQ_REMOVE(&ccbq->queue_extra_head, &ccb->ccb_h, xpt_links.tqe); ccb->ccb_h.pinfo.index = CAM_UNQUEUED_INDEX; ccbq->queue_extra_entries--; return; } camq_remove(queue, ccb->ccb_h.pinfo.index); /* * If there are some CCBs on TAILQ, find the best one and move it * to the emptied space in the queue. */ bccb = TAILQ_FIRST(&ccbq->queue_extra_head); if (bccb == NULL) return; TAILQ_FOREACH(cccb, &ccbq->queue_extra_head, xpt_links.tqe) { if (bccb->pinfo.priority > cccb->pinfo.priority || (bccb->pinfo.priority == cccb->pinfo.priority && GENERATIONCMP(bccb->pinfo.generation, >, cccb->pinfo.generation))) bccb = cccb; } TAILQ_REMOVE(&ccbq->queue_extra_head, bccb, xpt_links.tqe); ccbq->queue_extra_entries--; camq_insert(queue, &bccb->pinfo); } static __inline union ccb * cam_ccbq_peek_ccb(struct cam_ccbq *ccbq, int index) { return((union ccb *)ccbq->queue.queue_array[index]); } static __inline void cam_ccbq_send_ccb(struct cam_ccbq *ccbq, union ccb *send_ccb) { send_ccb->ccb_h.pinfo.index = CAM_ACTIVE_INDEX; ccbq->dev_active++; ccbq->dev_openings--; } static __inline void cam_ccbq_ccb_done(struct cam_ccbq *ccbq, union ccb *done_ccb) { ccbq->dev_active--; ccbq->dev_openings++; } static __inline void cam_ccbq_release_opening(struct cam_ccbq *ccbq) { ccbq->allocated--; } #endif /* _KERNEL */ #endif /* _CAM_CAM_QUEUE_H */