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 000000000000..6aff9740c3df --- /dev/null +++ b/drivers/scsi/fnic/vnic_wq_copy.h | |||
@@ -0,0 +1,128 @@ | |||
1 | /* | ||
2 | * Copyright 2008 Cisco Systems, Inc. All rights reserved. | ||
3 | * Copyright 2007 Nuova Systems, Inc. All rights reserved. | ||
4 | * | ||
5 | * This program is free software; you may redistribute it and/or modify | ||
6 | * it under the terms of the GNU General Public License as published by | ||
7 | * the Free Software Foundation; version 2 of the License. | ||
8 | * | ||
9 | * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, | ||
10 | * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF | ||
11 | * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND | ||
12 | * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS | ||
13 | * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN | ||
14 | * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN | ||
15 | * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE | ||
16 | * SOFTWARE. | ||
17 | */ | ||
18 | #ifndef _VNIC_WQ_COPY_H_ | ||
19 | #define _VNIC_WQ_COPY_H_ | ||
20 | |||
21 | #include <linux/pci.h> | ||
22 | #include "vnic_wq.h" | ||
23 | #include "fcpio.h" | ||
24 | |||
25 | #define VNIC_WQ_COPY_MAX 1 | ||
26 | |||
27 | struct vnic_wq_copy { | ||
28 | unsigned int index; | ||
29 | struct vnic_dev *vdev; | ||
30 | struct vnic_wq_ctrl __iomem *ctrl; /* memory-mapped */ | ||
31 | struct vnic_dev_ring ring; | ||
32 | unsigned to_use_index; | ||
33 | unsigned to_clean_index; | ||
34 | }; | ||
35 | |||
36 | static inline unsigned int vnic_wq_copy_desc_avail(struct vnic_wq_copy *wq) | ||
37 | { | ||
38 | return wq->ring.desc_avail; | ||
39 | } | ||
40 | |||
41 | static inline unsigned int vnic_wq_copy_desc_in_use(struct vnic_wq_copy *wq) | ||
42 | { | ||
43 | return wq->ring.desc_count - 1 - wq->ring.desc_avail; | ||
44 | } | ||
45 | |||
46 | static inline void *vnic_wq_copy_next_desc(struct vnic_wq_copy *wq) | ||
47 | { | ||
48 | struct fcpio_host_req *desc = wq->ring.descs; | ||
49 | return &desc[wq->to_use_index]; | ||
50 | } | ||
51 | |||
52 | static inline void vnic_wq_copy_post(struct vnic_wq_copy *wq) | ||
53 | { | ||
54 | |||
55 | ((wq->to_use_index + 1) == wq->ring.desc_count) ? | ||
56 | (wq->to_use_index = 0) : (wq->to_use_index++); | ||
57 | wq->ring.desc_avail--; | ||
58 | |||
59 | /* Adding write memory barrier prevents compiler and/or CPU | ||
60 | * reordering, thus avoiding descriptor posting before | ||
61 | * descriptor is initialized. Otherwise, hardware can read | ||
62 | * stale descriptor fields. | ||
63 | */ | ||
64 | wmb(); | ||
65 | |||
66 | iowrite32(wq->to_use_index, &wq->ctrl->posted_index); | ||
67 | } | ||
68 | |||
69 | static inline void vnic_wq_copy_desc_process(struct vnic_wq_copy *wq, u16 index) | ||
70 | { | ||
71 | unsigned int cnt; | ||
72 | |||
73 | if (wq->to_clean_index <= index) | ||
74 | cnt = (index - wq->to_clean_index) + 1; | ||
75 | else | ||
76 | cnt = wq->ring.desc_count - wq->to_clean_index + index + 1; | ||
77 | |||
78 | wq->to_clean_index = ((index + 1) % wq->ring.desc_count); | ||
79 | wq->ring.desc_avail += cnt; | ||
80 | |||
81 | } | ||
82 | |||
83 | static inline void vnic_wq_copy_service(struct vnic_wq_copy *wq, | ||
84 | u16 completed_index, | ||
85 | void (*q_service)(struct vnic_wq_copy *wq, | ||
86 | struct fcpio_host_req *wq_desc)) | ||
87 | { | ||
88 | struct fcpio_host_req *wq_desc = wq->ring.descs; | ||
89 | unsigned int curr_index; | ||
90 | |||
91 | while (1) { | ||
92 | |||
93 | if (q_service) | ||
94 | (*q_service)(wq, &wq_desc[wq->to_clean_index]); | ||
95 | |||
96 | wq->ring.desc_avail++; | ||
97 | |||
98 | curr_index = wq->to_clean_index; | ||
99 | |||
100 | /* increment the to-clean index so that we start | ||
101 | * with an unprocessed index next time we enter the loop | ||
102 | */ | ||
103 | ((wq->to_clean_index + 1) == wq->ring.desc_count) ? | ||
104 | (wq->to_clean_index = 0) : (wq->to_clean_index++); | ||
105 | |||
106 | if (curr_index == completed_index) | ||
107 | break; | ||
108 | |||
109 | /* we have cleaned all the entries */ | ||
110 | if ((completed_index == (u16)-1) && | ||
111 | (wq->to_clean_index == wq->to_use_index)) | ||
112 | break; | ||
113 | } | ||
114 | } | ||
115 | |||
116 | void vnic_wq_copy_enable(struct vnic_wq_copy *wq); | ||
117 | int vnic_wq_copy_disable(struct vnic_wq_copy *wq); | ||
118 | void vnic_wq_copy_free(struct vnic_wq_copy *wq); | ||
119 | int vnic_wq_copy_alloc(struct vnic_dev *vdev, struct vnic_wq_copy *wq, | ||
120 | unsigned int index, unsigned int desc_count, unsigned int desc_size); | ||
121 | void vnic_wq_copy_init(struct vnic_wq_copy *wq, unsigned int cq_index, | ||
122 | unsigned int error_interrupt_enable, | ||
123 | unsigned int error_interrupt_offset); | ||
124 | void vnic_wq_copy_clean(struct vnic_wq_copy *wq, | ||
125 | void (*q_clean)(struct vnic_wq_copy *wq, | ||
126 | struct fcpio_host_req *wq_desc)); | ||
127 | |||
128 | #endif /* _VNIC_WQ_COPY_H_ */ | ||