include/linux/sunrpc/svc_rdma_pcl.h

   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  */
  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  */
  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 *
  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 *
  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
 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 */