vnic_wq_copy.h
/*
* Copyright 2008 Cisco Systems, Inc. All rights reserved.
* Copyright 2007 Nuova Systems, Inc. All rights reserved.
*
* This program is free software; you may redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; version 2 of the License.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
* EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
* MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
* NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
* BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
* ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
* CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
* SOFTWARE.
*/
#ifndef _VNIC_WQ_COPY_H_
#define _VNIC_WQ_COPY_H_
#include <linux/pci.h>
#include "vnic_wq.h"
#include "fcpio.h"
#define VNIC_WQ_COPY_MAX 1
struct vnic_wq_copy {
unsigned int index;
struct vnic_dev *vdev;
struct vnic_wq_ctrl __iomem *ctrl; /* memory-mapped */
struct vnic_dev_ring ring;
unsigned to_use_index;
unsigned to_clean_index;
};
static inline unsigned int vnic_wq_copy_desc_avail(struct vnic_wq_copy *wq)
{
return wq->ring.desc_avail;
}
static inline unsigned int vnic_wq_copy_desc_in_use(struct vnic_wq_copy *wq)
{
return wq->ring.desc_count - 1 - wq->ring.desc_avail;
}
static inline void *vnic_wq_copy_next_desc(struct vnic_wq_copy *wq)
{
struct fcpio_host_req *desc = wq->ring.descs;
return &desc[wq->to_use_index];
}
static inline void vnic_wq_copy_post(struct vnic_wq_copy *wq)
{
((wq->to_use_index + 1) == wq->ring.desc_count) ?
(wq->to_use_index = 0) : (wq->to_use_index++);
wq->ring.desc_avail--;
/* Adding write memory barrier prevents compiler and/or CPU
* reordering, thus avoiding descriptor posting before
* descriptor is initialized. Otherwise, hardware can read
* stale descriptor fields.
*/
wmb();
iowrite32(wq->to_use_index, &wq->ctrl->posted_index);
}
static inline void vnic_wq_copy_desc_process(struct vnic_wq_copy *wq, u16 index)
{
unsigned int cnt;
if (wq->to_clean_index <= index)
cnt = (index - wq->to_clean_index) + 1;
else
cnt = wq->ring.desc_count - wq->to_clean_index + index + 1;
wq->to_clean_index = ((index + 1) % wq->ring.desc_count);
wq->ring.desc_avail += cnt;
}
static inline void vnic_wq_copy_service(struct vnic_wq_copy *wq,
u16 completed_index,
void (*q_service)(struct vnic_wq_copy *wq,
struct fcpio_host_req *wq_desc))
{
struct fcpio_host_req *wq_desc = wq->ring.descs;
unsigned int curr_index;
while (1) {
if (q_service)
(*q_service)(wq, &wq_desc[wq->to_clean_index]);
wq->ring.desc_avail++;
curr_index = wq->to_clean_index;
/* increment the to-clean index so that we start
* with an unprocessed index next time we enter the loop
*/
((wq->to_clean_index + 1) == wq->ring.desc_count) ?
(wq->to_clean_index = 0) : (wq->to_clean_index++);
if (curr_index == completed_index)
break;
/* we have cleaned all the entries */
if ((completed_index == (u16)-1) &&
(wq->to_clean_index == wq->to_use_index))
break;
}
}
void vnic_wq_copy_enable(struct vnic_wq_copy *wq);
int vnic_wq_copy_disable(struct vnic_wq_copy *wq);
void vnic_wq_copy_free(struct vnic_wq_copy *wq);
int vnic_wq_copy_alloc(struct vnic_dev *vdev, struct vnic_wq_copy *wq,
unsigned int index, unsigned int desc_count, unsigned int desc_size);
void vnic_wq_copy_init(struct vnic_wq_copy *wq, unsigned int cq_index,
unsigned int error_interrupt_enable,
unsigned int error_interrupt_offset);
void vnic_wq_copy_clean(struct vnic_wq_copy *wq,
void (*q_clean)(struct vnic_wq_copy *wq,
struct fcpio_host_req *wq_desc));
#endif /* _VNIC_WQ_COPY_H_ */