xref: /linux/include/linux/sunrpc/svc_rdma_pcl.h (revision cdd38c5f1ce4398ec58fec95904b75824daab7b5)
1 /* SPDX-License-Identifier: GPL-2.0 */
2 /*
3  * Copyright (c) 2020, Oracle and/or its affiliates
4  */
5 
6 #ifndef SVC_RDMA_PCL_H
7 #define SVC_RDMA_PCL_H
8 
9 #include <linux/list.h>
10 
11 struct svc_rdma_segment {
12 	u32			rs_handle;
13 	u32			rs_length;
14 	u64			rs_offset;
15 };
16 
17 struct svc_rdma_chunk {
18 	struct list_head	ch_list;
19 
20 	u32			ch_position;
21 	u32			ch_length;
22 	u32			ch_payload_length;
23 
24 	u32			ch_segcount;
25 	struct svc_rdma_segment	ch_segments[];
26 };
27 
28 struct svc_rdma_pcl {
29 	unsigned int		cl_count;
30 	struct list_head	cl_chunks;
31 };
32 
33 /**
34  * pcl_init - Initialize a parsed chunk list
35  * @pcl: parsed chunk list to initialize
36  *
37  */
pcl_init(struct svc_rdma_pcl * pcl)38 static inline void pcl_init(struct svc_rdma_pcl *pcl)
39 {
40 	INIT_LIST_HEAD(&pcl->cl_chunks);
41 }
42 
43 /**
44  * pcl_is_empty - Return true if parsed chunk list is empty
45  * @pcl: parsed chunk list
46  *
47  */
pcl_is_empty(const struct svc_rdma_pcl * pcl)48 static inline bool pcl_is_empty(const struct svc_rdma_pcl *pcl)
49 {
50 	return list_empty(&pcl->cl_chunks);
51 }
52 
53 /**
54  * pcl_first_chunk - Return first chunk in a parsed chunk list
55  * @pcl: parsed chunk list
56  *
57  * Returns the first chunk in the list, or NULL if the list is empty.
58  */
59 static inline struct svc_rdma_chunk *
pcl_first_chunk(const struct svc_rdma_pcl * pcl)60 pcl_first_chunk(const struct svc_rdma_pcl *pcl)
61 {
62 	if (pcl_is_empty(pcl))
63 		return NULL;
64 	return list_first_entry(&pcl->cl_chunks, struct svc_rdma_chunk,
65 				ch_list);
66 }
67 
68 /**
69  * pcl_next_chunk - Return next chunk in a parsed chunk list
70  * @pcl: a parsed chunk list
71  * @chunk: chunk in @pcl
72  *
73  * Returns the next chunk in the list, or NULL if @chunk is already last.
74  */
75 static inline struct svc_rdma_chunk *
pcl_next_chunk(const struct svc_rdma_pcl * pcl,struct svc_rdma_chunk * chunk)76 pcl_next_chunk(const struct svc_rdma_pcl *pcl, struct svc_rdma_chunk *chunk)
77 {
78 	if (list_is_last(&chunk->ch_list, &pcl->cl_chunks))
79 		return NULL;
80 	return list_next_entry(chunk, ch_list);
81 }
82 
83 /**
84  * pcl_for_each_chunk - Iterate over chunks in a parsed chunk list
85  * @pos: the loop cursor
86  * @pcl: a parsed chunk list
87  */
88 #define pcl_for_each_chunk(pos, pcl) \
89 	for (pos = list_first_entry(&(pcl)->cl_chunks, struct svc_rdma_chunk, ch_list); \
90 	     &pos->ch_list != &(pcl)->cl_chunks; \
91 	     pos = list_next_entry(pos, ch_list))
92 
93 /**
94  * pcl_for_each_segment - Iterate over segments in a parsed chunk
95  * @pos: the loop cursor
96  * @chunk: a parsed chunk
97  */
98 #define pcl_for_each_segment(pos, chunk) \
99 	for (pos = &(chunk)->ch_segments[0]; \
100 	     pos <= &(chunk)->ch_segments[(chunk)->ch_segcount - 1]; \
101 	     pos++)
102 
103 /**
104  * pcl_chunk_end_offset - Return offset of byte range following @chunk
105  * @chunk: chunk in @pcl
106  *
107  * Returns starting offset of the region just after @chunk
108  */
109 static inline unsigned int
pcl_chunk_end_offset(const struct svc_rdma_chunk * chunk)110 pcl_chunk_end_offset(const struct svc_rdma_chunk *chunk)
111 {
112 	return xdr_align_size(chunk->ch_position + chunk->ch_payload_length);
113 }
114 
115 struct svc_rdma_recv_ctxt;
116 
117 extern void pcl_free(struct svc_rdma_pcl *pcl);
118 extern bool pcl_alloc_call(struct svc_rdma_recv_ctxt *rctxt, __be32 *p);
119 extern bool pcl_alloc_read(struct svc_rdma_recv_ctxt *rctxt, __be32 *p);
120 extern bool pcl_alloc_write(struct svc_rdma_recv_ctxt *rctxt,
121 			    struct svc_rdma_pcl *pcl, __be32 *p);
122 extern int pcl_process_nonpayloads(const struct svc_rdma_pcl *pcl,
123 				   const struct xdr_buf *xdr,
124 				   int (*actor)(const struct xdr_buf *,
125 						void *),
126 				   void *data);
127 
128 #endif	/* SVC_RDMA_PCL_H */
129