[linux-2.6-block.git] / drivers / staging / rdma / hfi1 / iowait.h

#ifndef _HFI1_IOWAIT_H
#define _HFI1_IOWAIT_H
/*
 *
 * This file is provided under a dual BSD/GPLv2 license.  When using or
 * redistributing this file, you may do so under either license.
 *
 * GPL LICENSE SUMMARY
 *
 * Copyright(c) 2015 Intel Corporation.
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of version 2 of the GNU General Public License as
 * published by the Free Software Foundation.
 *
 * This program is distributed in the hope that it will be useful, but
 * WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 * General Public License for more details.
 *
 * BSD LICENSE
 *
 * Copyright(c) 2015 Intel Corporation.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 *
 *  - Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 *  - Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in
 *    the documentation and/or other materials provided with the
 *    distribution.
 *  - Neither the name of Intel Corporation nor the names of its
 *    contributors may be used to endorse or promote products derived
 *    from this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS 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 COPYRIGHT
 * OWNER 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.
 *
 */

#include <linux/list.h>
#include <linux/workqueue.h>
#include <linux/sched.h>

#include "sdma_txreq.h"

/*
 * typedef (*restart_t)() - restart callback
 * @work: pointer to work structure
 */
typedef void (*restart_t)(struct work_struct *work);

struct sdma_txreq;
struct sdma_engine;
/**
 * struct iowait - linkage for delayed progress/waiting
 * @list: used to add/insert into QP/PQ wait lists
 * @tx_head: overflow list of sdma_txreq's
 * @sleep: no space callback
 * @wakeup: space callback wakeup
 * @sdma_drained: sdma count drained
 * @iowork: workqueue overhead
 * @wait_dma: wait for sdma_busy == 0
 * @wait_pio: wait for pio_busy == 0
 * @sdma_busy: # of packets in flight
 * @count: total number of descriptors in tx_head'ed list
 * @tx_limit: limit for overflow queuing
 * @tx_count: number of tx entry's in tx_head'ed list
 *
 * This is to be embedded in user's state structure
 * (QP or PQ).
 *
 * The sleep and wakeup members are a
 * bit misnamed.   They do not strictly
 * speaking sleep or wake up, but they
 * are callbacks for the ULP to implement
 * what ever queuing/dequeuing of
 * the embedded iowait and its containing struct
 * when a resource shortage like SDMA ring space is seen.
 *
 * Both potentially have locks help
 * so sleeping is not allowed.
 *
 * The wait_dma member along with the iow
 */

struct iowait {
	struct list_head list;
	struct list_head tx_head;
	int (*sleep)(
		struct sdma_engine *sde,
		struct iowait *wait,
		struct sdma_txreq *tx,
		unsigned seq);
	void (*wakeup)(struct iowait *wait, int reason);
	void (*sdma_drained)(struct iowait *wait);
	struct work_struct iowork;
	wait_queue_head_t wait_dma;
	wait_queue_head_t wait_pio;
	atomic_t sdma_busy;
	atomic_t pio_busy;
	u32 count;
	u32 tx_limit;
	u32 tx_count;
};

#define SDMA_AVAIL_REASON 0

/**
 * iowait_init() - initialize wait structure
 * @wait: wait struct to initialize
 * @tx_limit: limit for overflow queuing
 * @func: restart function for workqueue
 * @sleep: sleep function for no space
 * @resume: wakeup function for no space
 *
 * This function initializes the iowait
 * structure embedded in the QP or PQ.
 *
 */

static inline void iowait_init(
	struct iowait *wait,
	u32 tx_limit,
	void (*func)(struct work_struct *work),
	int (*sleep)(
		struct sdma_engine *sde,
		struct iowait *wait,
		struct sdma_txreq *tx,
		unsigned seq),
	void (*wakeup)(struct iowait *wait, int reason),
	void (*sdma_drained)(struct iowait *wait))
{
	wait->count = 0;
	INIT_LIST_HEAD(&wait->list);
	INIT_LIST_HEAD(&wait->tx_head);
	INIT_WORK(&wait->iowork, func);
	init_waitqueue_head(&wait->wait_dma);
	init_waitqueue_head(&wait->wait_pio);
	atomic_set(&wait->sdma_busy, 0);
	atomic_set(&wait->pio_busy, 0);
	wait->tx_limit = tx_limit;
	wait->sleep = sleep;
	wait->wakeup = wakeup;
	wait->sdma_drained = sdma_drained;
}

/**
 * iowait_schedule() - initialize wait structure
 * @wait: wait struct to schedule
 * @wq: workqueue for schedule
 * @cpu: cpu
 */
static inline void iowait_schedule(
	struct iowait *wait,
	struct workqueue_struct *wq,
	int cpu)
{
	queue_work_on(cpu, wq, &wait->iowork);
}

/**
 * iowait_sdma_drain() - wait for DMAs to drain
 *
 * @wait: iowait structure
 *
 * This will delay until the iowait sdmas have
 * completed.
 */
static inline void iowait_sdma_drain(struct iowait *wait)
{
	wait_event(wait->wait_dma, !atomic_read(&wait->sdma_busy));
}

/**
 * iowait_sdma_pending() - return sdma pending count
 *
 * @wait: iowait structure
 *
 */
static inline int iowait_sdma_pending(struct iowait *wait)
{
	return atomic_read(&wait->sdma_busy);
}

/**
 * iowait_sdma_inc - note sdma io pending
 * @wait: iowait structure
 */
static inline void iowait_sdma_inc(struct iowait *wait)
{
	atomic_inc(&wait->sdma_busy);
}

/**
 * iowait_sdma_add - add count to pending
 * @wait: iowait structure
 */
static inline void iowait_sdma_add(struct iowait *wait, int count)
{
	atomic_add(count, &wait->sdma_busy);
}

/**
 * iowait_sdma_dec - note sdma complete
 * @wait: iowait structure
 */
static inline int iowait_sdma_dec(struct iowait *wait)
{
	return atomic_dec_and_test(&wait->sdma_busy);
}

/**
 * iowait_pio_drain() - wait for pios to drain
 *
 * @wait: iowait structure
 *
 * This will delay until the iowait pios have
 * completed.
 */
static inline void iowait_pio_drain(struct iowait *wait)
{
	wait_event_timeout(wait->wait_pio,
			   !atomic_read(&wait->pio_busy),
			   HZ);
}

/**
 * iowait_pio_pending() - return pio pending count
 *
 * @wait: iowait structure
 *
 */
static inline int iowait_pio_pending(struct iowait *wait)
{
	return atomic_read(&wait->pio_busy);
}

/**
 * iowait_pio_inc - note pio pending
 * @wait: iowait structure
 */
static inline void iowait_pio_inc(struct iowait *wait)
{
	atomic_inc(&wait->pio_busy);
}

/**
 * iowait_sdma_dec - note pio complete
 * @wait: iowait structure
 */
static inline int iowait_pio_dec(struct iowait *wait)
{
	return atomic_dec_and_test(&wait->pio_busy);
}

/**
 * iowait_drain_wakeup() - trigger iowait_drain() waiter
 *
 * @wait: iowait structure
 *
 * This will trigger any waiters.
 */
static inline void iowait_drain_wakeup(struct iowait *wait)
{
	wake_up(&wait->wait_dma);
	wake_up(&wait->wait_pio);
	if (wait->sdma_drained)
		wait->sdma_drained(wait);
}

/**
 * iowait_get_txhead() - get packet off of iowait list
 *
 * @wait wait struture
 */
static inline struct sdma_txreq *iowait_get_txhead(struct iowait *wait)
{
	struct sdma_txreq *tx = NULL;

	if (!list_empty(&wait->tx_head)) {
		tx = list_first_entry(
			&wait->tx_head,
			struct sdma_txreq,
			list);
		list_del_init(&tx->list);
	}
	return tx;
}

#endif
Commit	Line	Data
77241056 MM	1	#ifndef _HFI1_IOWAIT_H
	2	#define _HFI1_IOWAIT_H
	3	/*
	4	*
	5	* This file is provided under a dual BSD/GPLv2 license. When using or
	6	* redistributing this file, you may do so under either license.
	7	*
	8	* GPL LICENSE SUMMARY
	9	*
	10	* Copyright(c) 2015 Intel Corporation.
	11	*
	12	* This program is free software; you can redistribute it and/or modify
	13	* it under the terms of version 2 of the GNU General Public License as
	14	* published by the Free Software Foundation.
	15	*
	16	* This program is distributed in the hope that it will be useful, but
	17	* WITHOUT ANY WARRANTY; without even the implied warranty of
	18	* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
	19	* General Public License for more details.
	20	*
	21	* BSD LICENSE
	22	*
	23	* Copyright(c) 2015 Intel Corporation.
	24	*
	25	* Redistribution and use in source and binary forms, with or without
	26	* modification, are permitted provided that the following conditions
	27	* are met:
	28	*
	29	* - Redistributions of source code must retain the above copyright
	30	* notice, this list of conditions and the following disclaimer.
	31	* - Redistributions in binary form must reproduce the above copyright
	32	* notice, this list of conditions and the following disclaimer in
	33	* the documentation and/or other materials provided with the
	34	* distribution.
	35	* - Neither the name of Intel Corporation nor the names of its
	36	* contributors may be used to endorse or promote products derived
	37	* from this software without specific prior written permission.
	38	*
	39	* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
	40	* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
	41	* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
	42	* A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
	43	* OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
	44	* SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
	45	* LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
	46	* DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
	47	* THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
	48	* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
	49	* OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
	50	*
	51	*/
	52
	53	#include <linux/list.h>
	54	#include <linux/workqueue.h>
	55	#include <linux/sched.h>
	56
711e104d	57	#include "sdma_txreq.h"
14553ca1	58
77241056 MM	59	/*
	60	* typedef (*restart_t)() - restart callback
	61	* @work: pointer to work structure
	62	*/
	63	typedef void (restart_t)(struct work_struct work);
	64
	65	struct sdma_txreq;
	66	struct sdma_engine;
	67	/**
	68	* struct iowait - linkage for delayed progress/waiting
	69	* @list: used to add/insert into QP/PQ wait lists
	70	* @tx_head: overflow list of sdma_txreq's
	71	* @sleep: no space callback
a545f530 MM	72	* @wakeup: space callback wakeup
a545f530 MM	73	* @sdma_drained: sdma count drained
77241056 MM	74	* @iowork: workqueue overhead
77241056 MM	75	* @wait_dma: wait for sdma_busy == 0
14553ca1	76	* @wait_pio: wait for pio_busy == 0
77241056 MM	77	* @sdma_busy: # of packets in flight
	78	* @count: total number of descriptors in tx_head'ed list
	79	* @tx_limit: limit for overflow queuing
	80	* @tx_count: number of tx entry's in tx_head'ed list
	81	*
	82	* This is to be embedded in user's state structure
	83	* (QP or PQ).
	84	*
	85	* The sleep and wakeup members are a
	86	* bit misnamed. They do not strictly
	87	* speaking sleep or wake up, but they
	88	* are callbacks for the ULP to implement
	89	* what ever queuing/dequeuing of
	90	* the embedded iowait and its containing struct
	91	* when a resource shortage like SDMA ring space is seen.
	92	*
	93	* Both potentially have locks help
	94	* so sleeping is not allowed.
	95	*
	96	* The wait_dma member along with the iow
	97	*/
	98
	99	struct iowait {
	100	struct list_head list;
	101	struct list_head tx_head;
	102	int (*sleep)(
	103	struct sdma_engine *sde,
	104	struct iowait *wait,
	105	struct sdma_txreq *tx,
	106	unsigned seq);
	107	void (wakeup)(struct iowait wait, int reason);
a545f530	108	void (sdma_drained)(struct iowait wait);
77241056 MM	109	struct work_struct iowork;
77241056 MM	110	wait_queue_head_t wait_dma;
14553ca1	111	wait_queue_head_t wait_pio;
77241056	112	atomic_t sdma_busy;
14553ca1	113	atomic_t pio_busy;
77241056 MM	114	u32 count;
	115	u32 tx_limit;
	116	u32 tx_count;
	117	};
	118
	119	#define SDMA_AVAIL_REASON 0
	120
	121	/**
	122	* iowait_init() - initialize wait structure
	123	* @wait: wait struct to initialize
	124	* @tx_limit: limit for overflow queuing
	125	* @func: restart function for workqueue
	126	* @sleep: sleep function for no space
a545f530	127	* @resume: wakeup function for no space
77241056 MM	128	*
	129	* This function initializes the iowait
	130	* structure embedded in the QP or PQ.
	131	*
	132	*/
	133
	134	static inline void iowait_init(
	135	struct iowait *wait,
	136	u32 tx_limit,
	137	void (func)(struct work_struct work),
	138	int (*sleep)(
	139	struct sdma_engine *sde,
	140	struct iowait *wait,
	141	struct sdma_txreq *tx,
	142	unsigned seq),
a545f530 MM	143	void (wakeup)(struct iowait wait, int reason),
a545f530 MM	144	void (sdma_drained)(struct iowait wait))
77241056 MM	145	{
	146	wait->count = 0;
	147	INIT_LIST_HEAD(&wait->list);
	148	INIT_LIST_HEAD(&wait->tx_head);
	149	INIT_WORK(&wait->iowork, func);
	150	init_waitqueue_head(&wait->wait_dma);
14553ca1	151	init_waitqueue_head(&wait->wait_pio);
77241056	152	atomic_set(&wait->sdma_busy, 0);
14553ca1	153	atomic_set(&wait->pio_busy, 0);
77241056 MM	154	wait->tx_limit = tx_limit;
	155	wait->sleep = sleep;
	156	wait->wakeup = wakeup;
a545f530	157	wait->sdma_drained = sdma_drained;
77241056 MM	158	}
	159
	160	/**
	161	* iowait_schedule() - initialize wait structure
	162	* @wait: wait struct to schedule
	163	* @wq: workqueue for schedule
0a226edd	164	* @cpu: cpu
77241056 MM	165	*/
	166	static inline void iowait_schedule(
	167	struct iowait *wait,
0a226edd MM	168	struct workqueue_struct *wq,
0a226edd MM	169	int cpu)
77241056	170	{
0a226edd	171	queue_work_on(cpu, wq, &wait->iowork);
77241056 MM	172	}
	173
	174	/**
	175	* iowait_sdma_drain() - wait for DMAs to drain
	176	*
	177	* @wait: iowait structure
	178	*
	179	* This will delay until the iowait sdmas have
	180	* completed.
	181	*/
	182	static inline void iowait_sdma_drain(struct iowait *wait)
	183	{
	184	wait_event(wait->wait_dma, !atomic_read(&wait->sdma_busy));
	185	}
	186
14553ca1 MM	187	/**
	188	* iowait_sdma_pending() - return sdma pending count
	189	*
	190	* @wait: iowait structure
	191	*
	192	*/
	193	static inline int iowait_sdma_pending(struct iowait *wait)
	194	{
	195	return atomic_read(&wait->sdma_busy);
	196	}
	197
	198	/**
	199	* iowait_sdma_inc - note sdma io pending
	200	* @wait: iowait structure
	201	*/
	202	static inline void iowait_sdma_inc(struct iowait *wait)
	203	{
	204	atomic_inc(&wait->sdma_busy);
	205	}
	206
	207	/**
	208	* iowait_sdma_add - add count to pending
	209	* @wait: iowait structure
	210	*/
	211	static inline void iowait_sdma_add(struct iowait *wait, int count)
	212	{
	213	atomic_add(count, &wait->sdma_busy);
	214	}
	215
	216	/**
	217	* iowait_sdma_dec - note sdma complete
	218	* @wait: iowait structure
	219	*/
	220	static inline int iowait_sdma_dec(struct iowait *wait)
	221	{
	222	return atomic_dec_and_test(&wait->sdma_busy);
	223	}
	224
	225	/**
	226	* iowait_pio_drain() - wait for pios to drain
	227	*
	228	* @wait: iowait structure
	229	*
	230	* This will delay until the iowait pios have
	231	* completed.
	232	*/
	233	static inline void iowait_pio_drain(struct iowait *wait)
	234	{
	235	wait_event_timeout(wait->wait_pio,
	236	!atomic_read(&wait->pio_busy),
	237	HZ);
	238	}
	239
	240	/**
	241	* iowait_pio_pending() - return pio pending count
	242	*
	243	* @wait: iowait structure
	244	*
	245	*/
	246	static inline int iowait_pio_pending(struct iowait *wait)
	247	{
	248	return atomic_read(&wait->pio_busy);
	249	}
	250
251	/**
252	* iowait_pio_inc - note pio pending
253	* @wait: iowait structure
254	*/
255	static inline void iowait_pio_inc(struct iowait *wait)
256	{
257	atomic_inc(&wait->pio_busy);
258	}
259
260	/**
261	* iowait_sdma_dec - note pio complete
262	* @wait: iowait structure
263	*/
264	static inline int iowait_pio_dec(struct iowait *wait)
265	{
266	return atomic_dec_and_test(&wait->pio_busy);
267	}
268
77241056 MM	269	/**
	270	* iowait_drain_wakeup() - trigger iowait_drain() waiter
	271	*
	272	* @wait: iowait structure
	273	*
	274	* This will trigger any waiters.
	275	*/
	276	static inline void iowait_drain_wakeup(struct iowait *wait)
	277	{
	278	wake_up(&wait->wait_dma);
14553ca1	279	wake_up(&wait->wait_pio);
a545f530 MM	280	if (wait->sdma_drained)
a545f530 MM	281	wait->sdma_drained(wait);
77241056 MM	282	}
77241056 MM	283
711e104d MM	284	/**
	285	* iowait_get_txhead() - get packet off of iowait list
	286	*
	287	* @wait wait struture
	288	*/
	289	static inline struct sdma_txreq iowait_get_txhead(struct iowait wait)
	290	{
	291	struct sdma_txreq *tx = NULL;
	292
	293	if (!list_empty(&wait->tx_head)) {
	294	tx = list_first_entry(
	295	&wait->tx_head,
	296	struct sdma_txreq,
	297	list);
	298	list_del_init(&tx->list);
	299	}
	300	return tx;
	301	}
	302
77241056	303	#endif