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
 11struct svc_rdma_segment {
 12	u32			rs_handle;
 13	u32			rs_length;
 14	u64			rs_offset;
 15};
 16
 17struct 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
 28struct 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 */
 38static 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 */
 48static 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 */
 59static inline struct svc_rdma_chunk *
 60pcl_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 */
 75static inline struct svc_rdma_chunk *
 76pcl_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 */
109static inline unsigned int
110pcl_chunk_end_offset(const struct svc_rdma_chunk *chunk)
111{
112	return xdr_align_size(chunk->ch_position + chunk->ch_payload_length);
113}
114
115struct svc_rdma_recv_ctxt;
116
117extern void pcl_free(struct svc_rdma_pcl *pcl);
118extern bool pcl_alloc_call(struct svc_rdma_recv_ctxt *rctxt, __be32 *p);
119extern bool pcl_alloc_read(struct svc_rdma_recv_ctxt *rctxt, __be32 *p);
120extern bool pcl_alloc_write(struct svc_rdma_recv_ctxt *rctxt,
121			    struct svc_rdma_pcl *pcl, __be32 *p);
122extern 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 */