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40  */
41 
42 #ifndef _LINUX_SUNRPC_RPC_RDMA_H
43 #define _LINUX_SUNRPC_RPC_RDMA_H
44 
45 #include <linux/types.h>
46 #include <linux/bitops.h>
47 
48 #define RPCRDMA_VERSION		1
49 #define rpcrdma_version		cpu_to_be32(RPCRDMA_VERSION)
50 
51 enum {
52 	RPCRDMA_V1_DEF_INLINE_SIZE	= 1024,
53 };
54 
55 /*
56  * XDR sizes, in quads
57  */
58 enum {
59 	rpcrdma_fixed_maxsz	= 4,
60 	rpcrdma_segment_maxsz	= 4,
61 	rpcrdma_readchunk_maxsz	= 2 + rpcrdma_segment_maxsz,
62 };
63 
64 /*
65  * Smallest RPC/RDMA header: rm_xid through rm_type, then rm_nochunks
66  */
67 #define RPCRDMA_HDRLEN_MIN	(sizeof(__be32) * 7)
68 #define RPCRDMA_HDRLEN_ERR	(sizeof(__be32) * 5)
69 
70 enum rpcrdma_errcode {
71 	ERR_VERS = 1,
72 	ERR_CHUNK = 2
73 };
74 
75 enum rpcrdma_proc {
76 	RDMA_MSG = 0,		/* An RPC call or reply msg */
77 	RDMA_NOMSG = 1,		/* An RPC call or reply msg - separate body */
78 	RDMA_MSGP = 2,		/* An RPC call or reply msg with padding */
79 	RDMA_DONE = 3,		/* Client signals reply completion */
80 	RDMA_ERROR = 4		/* An RPC RDMA encoding error */
81 };
82 
83 #define rdma_msg	cpu_to_be32(RDMA_MSG)
84 #define rdma_nomsg	cpu_to_be32(RDMA_NOMSG)
85 #define rdma_msgp	cpu_to_be32(RDMA_MSGP)
86 #define rdma_done	cpu_to_be32(RDMA_DONE)
87 #define rdma_error	cpu_to_be32(RDMA_ERROR)
88 
89 #define err_vers	cpu_to_be32(ERR_VERS)
90 #define err_chunk	cpu_to_be32(ERR_CHUNK)
91 
92 /*
93  * Private extension to RPC-over-RDMA Version One.
94  * Message passed during RDMA-CM connection set-up.
95  *
96  * Add new fields at the end, and don't permute existing
97  * fields.
98  */
99 struct rpcrdma_connect_private {
100 	__be32			cp_magic;
101 	u8			cp_version;
102 	u8			cp_flags;
103 	u8			cp_send_size;
104 	u8			cp_recv_size;
105 } __packed;
106 
107 #define rpcrdma_cmp_magic	__cpu_to_be32(0xf6ab0e18)
108 
109 enum {
110 	RPCRDMA_CMP_VERSION		= 1,
111 	RPCRDMA_CMP_F_SND_W_INV_OK	= BIT(0),
112 };
113 
114 static inline u8
rpcrdma_encode_buffer_size(unsigned int size)115 rpcrdma_encode_buffer_size(unsigned int size)
116 {
117 	return (size >> 10) - 1;
118 }
119 
120 static inline unsigned int
rpcrdma_decode_buffer_size(u8 val)121 rpcrdma_decode_buffer_size(u8 val)
122 {
123 	return ((unsigned int)val + 1) << 10;
124 }
125 
126 #endif				/* _LINUX_SUNRPC_RPC_RDMA_H */
127