freebsd-skq/sys/cam/cam_queue.h

236 lines
6.0 KiB
C

/*-
* 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/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;
int devq_openings;
int devq_allocating;
int dev_openings;
int dev_active;
int held;
};
struct cam_ed;
struct cam_devq {
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);
}
static __inline void
cam_ccbq_take_opening(struct cam_ccbq *ccbq)
{
ccbq->devq_openings--;
ccbq->held++;
}
static __inline void
cam_ccbq_insert_ccb(struct cam_ccbq *ccbq, union ccb *new_ccb)
{
ccbq->held--;
camq_insert(&ccbq->queue, &new_ccb->ccb_h.pinfo);
}
static __inline void
cam_ccbq_remove_ccb(struct cam_ccbq *ccbq, union ccb *ccb)
{
camq_remove(&ccbq->queue, ccb->ccb_h.pinfo.index);
}
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++;
ccbq->held++;
}
static __inline void
cam_ccbq_release_opening(struct cam_ccbq *ccbq)
{
ccbq->held--;
ccbq->devq_openings++;
}
#endif /* _KERNEL */
#endif /* _CAM_CAM_QUEUE_H */