diff options
Diffstat (limited to 'drivers/scsi/fnic/vnic_wq_copy.h')
| -rw-r--r-- | drivers/scsi/fnic/vnic_wq_copy.h | 128 |
1 files changed, 128 insertions, 0 deletions
diff --git a/drivers/scsi/fnic/vnic_wq_copy.h b/drivers/scsi/fnic/vnic_wq_copy.h new file mode 100644 index 00000000000..6aff9740c3d --- /dev/null +++ b/drivers/scsi/fnic/vnic_wq_copy.h @@ -0,0 +1,128 @@ +/* + * 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_ */ |