1 /* SPDX-License-Identifier: GPL-2.0 OR BSD-3-Clause */
2 /*
3  * Copyright (c) 2005-2006 Network Appliance, Inc. All rights reserved.
4  *
5  * This software is available to you under a choice of one of two
6  * licenses.  You may choose to be licensed under the terms of the GNU
7  * General Public License (GPL) Version 2, available from the file
8  * COPYING in the main directory of this source tree, or the BSD-type
9  * license below:
10  *
11  * Redistribution and use in source and binary forms, with or without
12  * modification, are permitted provided that the following conditions
13  * are met:
14  *
15  *      Redistributions of source code must retain the above copyright
16  *      notice, this list of conditions and the following disclaimer.
17  *
18  *      Redistributions in binary form must reproduce the above
19  *      copyright notice, this list of conditions and the following
20  *      disclaimer in the documentation and/or other materials provided
21  *      with the distribution.
22  *
23  *      Neither the name of the Network Appliance, Inc. nor the names of
24  *      its contributors may be used to endorse or promote products
25  *      derived from this software without specific prior written
26  *      permission.
27  *
28  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
29  * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
30  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
31  * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
32  * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
33  * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
34  * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
35  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
36  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
37  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
38  * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
39  *
40  * Author: Tom Tucker <tom@opengridcomputing.com>
41  */
42 
43 #ifndef SVC_RDMA_H
44 #define SVC_RDMA_H
45 #include <linux/llist.h>
46 #include <linux/sunrpc/xdr.h>
47 #include <linux/sunrpc/svcsock.h>
48 #include <linux/sunrpc/rpc_rdma.h>
49 #include <linux/sunrpc/rpc_rdma_cid.h>
50 #include <linux/sunrpc/svc_rdma_pcl.h>
51 
52 #include <linux/percpu_counter.h>
53 #include <rdma/ib_verbs.h>
54 #include <rdma/rdma_cm.h>
55 
56 /* Default and maximum inline threshold sizes */
57 enum {
58 	RPCRDMA_PULLUP_THRESH = RPCRDMA_V1_DEF_INLINE_SIZE >> 1,
59 	RPCRDMA_DEF_INLINE_THRESH = 4096,
60 	RPCRDMA_MAX_INLINE_THRESH = 65536
61 };
62 
63 /* RPC/RDMA parameters and stats */
64 extern unsigned int svcrdma_ord;
65 extern unsigned int svcrdma_max_requests;
66 extern unsigned int svcrdma_max_bc_requests;
67 extern unsigned int svcrdma_max_req_size;
68 
69 extern struct percpu_counter svcrdma_stat_read;
70 extern struct percpu_counter svcrdma_stat_recv;
71 extern struct percpu_counter svcrdma_stat_sq_starve;
72 extern struct percpu_counter svcrdma_stat_write;
73 
74 struct svcxprt_rdma {
75 	struct svc_xprt      sc_xprt;		/* SVC transport structure */
76 	struct rdma_cm_id    *sc_cm_id;		/* RDMA connection id */
77 	struct list_head     sc_accept_q;	/* Conn. waiting accept */
78 	int		     sc_ord;		/* RDMA read limit */
79 	int                  sc_max_send_sges;
80 	bool		     sc_snd_w_inv;	/* OK to use Send With Invalidate */
81 
82 	atomic_t             sc_sq_avail;	/* SQEs ready to be consumed */
83 	unsigned int	     sc_sq_depth;	/* Depth of SQ */
84 	__be32		     sc_fc_credits;	/* Forward credits */
85 	u32		     sc_max_requests;	/* Max requests */
86 	u32		     sc_max_bc_requests;/* Backward credits */
87 	int                  sc_max_req_size;	/* Size of each RQ WR buf */
88 	u8		     sc_port_num;
89 
90 	struct ib_pd         *sc_pd;
91 
92 	spinlock_t	     sc_send_lock;
93 	struct llist_head    sc_send_ctxts;
94 	spinlock_t	     sc_rw_ctxt_lock;
95 	struct llist_head    sc_rw_ctxts;
96 
97 	u32		     sc_pending_recvs;
98 	u32		     sc_recv_batch;
99 	struct list_head     sc_rq_dto_q;
100 	spinlock_t	     sc_rq_dto_lock;
101 	struct ib_qp         *sc_qp;
102 	struct ib_cq         *sc_rq_cq;
103 	struct ib_cq         *sc_sq_cq;
104 
105 	spinlock_t	     sc_lock;		/* transport lock */
106 
107 	wait_queue_head_t    sc_send_wait;	/* SQ exhaustion waitlist */
108 	unsigned long	     sc_flags;
109 	struct work_struct   sc_work;
110 
111 	struct llist_head    sc_recv_ctxts;
112 
113 	atomic_t	     sc_completion_ids;
114 };
115 /* sc_flags */
116 #define RDMAXPRT_CONN_PENDING	3
117 
118 /*
119  * Default connection parameters
120  */
121 enum {
122 	RPCRDMA_LISTEN_BACKLOG	= 10,
123 	RPCRDMA_MAX_REQUESTS	= 64,
124 	RPCRDMA_MAX_BC_REQUESTS	= 2,
125 };
126 
127 #define RPCSVC_MAXPAYLOAD_RDMA	RPCSVC_MAXPAYLOAD
128 
129 struct svc_rdma_recv_ctxt {
130 	struct llist_node	rc_node;
131 	struct list_head	rc_list;
132 	struct ib_recv_wr	rc_recv_wr;
133 	struct ib_cqe		rc_cqe;
134 	struct rpc_rdma_cid	rc_cid;
135 	struct ib_sge		rc_recv_sge;
136 	void			*rc_recv_buf;
137 	struct xdr_stream	rc_stream;
138 	bool			rc_temp;
139 	u32			rc_byte_len;
140 	unsigned int		rc_page_count;
141 	u32			rc_inv_rkey;
142 	__be32			rc_msgtype;
143 
144 	struct svc_rdma_pcl	rc_call_pcl;
145 
146 	struct svc_rdma_pcl	rc_read_pcl;
147 	struct svc_rdma_chunk	*rc_cur_result_payload;
148 	struct svc_rdma_pcl	rc_write_pcl;
149 	struct svc_rdma_pcl	rc_reply_pcl;
150 };
151 
152 struct svc_rdma_send_ctxt {
153 	struct llist_node	sc_node;
154 	struct rpc_rdma_cid	sc_cid;
155 
156 	struct ib_send_wr	sc_send_wr;
157 	struct ib_cqe		sc_cqe;
158 	struct completion	sc_done;
159 	struct xdr_buf		sc_hdrbuf;
160 	struct xdr_stream	sc_stream;
161 	void			*sc_xprt_buf;
162 	int			sc_cur_sge_no;
163 
164 	struct ib_sge		sc_sges[];
165 };
166 
167 /* svc_rdma_backchannel.c */
168 extern void svc_rdma_handle_bc_reply(struct svc_rqst *rqstp,
169 				     struct svc_rdma_recv_ctxt *rctxt);
170 
171 /* svc_rdma_recvfrom.c */
172 extern void svc_rdma_recv_ctxts_destroy(struct svcxprt_rdma *rdma);
173 extern bool svc_rdma_post_recvs(struct svcxprt_rdma *rdma);
174 extern struct svc_rdma_recv_ctxt *
175 		svc_rdma_recv_ctxt_get(struct svcxprt_rdma *rdma);
176 extern void svc_rdma_recv_ctxt_put(struct svcxprt_rdma *rdma,
177 				   struct svc_rdma_recv_ctxt *ctxt);
178 extern void svc_rdma_flush_recv_queues(struct svcxprt_rdma *rdma);
179 extern void svc_rdma_release_rqst(struct svc_rqst *rqstp);
180 extern int svc_rdma_recvfrom(struct svc_rqst *);
181 
182 /* svc_rdma_rw.c */
183 extern void svc_rdma_destroy_rw_ctxts(struct svcxprt_rdma *rdma);
184 extern int svc_rdma_send_write_chunk(struct svcxprt_rdma *rdma,
185 				     const struct svc_rdma_chunk *chunk,
186 				     const struct xdr_buf *xdr);
187 extern int svc_rdma_send_reply_chunk(struct svcxprt_rdma *rdma,
188 				     const struct svc_rdma_recv_ctxt *rctxt,
189 				     const struct xdr_buf *xdr);
190 extern int svc_rdma_process_read_list(struct svcxprt_rdma *rdma,
191 				      struct svc_rqst *rqstp,
192 				      struct svc_rdma_recv_ctxt *head);
193 
194 /* svc_rdma_sendto.c */
195 extern void svc_rdma_send_ctxts_destroy(struct svcxprt_rdma *rdma);
196 extern struct svc_rdma_send_ctxt *
197 		svc_rdma_send_ctxt_get(struct svcxprt_rdma *rdma);
198 extern void svc_rdma_send_ctxt_put(struct svcxprt_rdma *rdma,
199 				   struct svc_rdma_send_ctxt *ctxt);
200 extern int svc_rdma_send(struct svcxprt_rdma *rdma,
201 			 struct svc_rdma_send_ctxt *ctxt);
202 extern int svc_rdma_map_reply_msg(struct svcxprt_rdma *rdma,
203 				  struct svc_rdma_send_ctxt *sctxt,
204 				  const struct svc_rdma_recv_ctxt *rctxt,
205 				  const struct xdr_buf *xdr);
206 extern void svc_rdma_send_error_msg(struct svcxprt_rdma *rdma,
207 				    struct svc_rdma_send_ctxt *sctxt,
208 				    struct svc_rdma_recv_ctxt *rctxt,
209 				    int status);
210 extern void svc_rdma_wake_send_waiters(struct svcxprt_rdma *rdma, int avail);
211 extern int svc_rdma_sendto(struct svc_rqst *);
212 extern int svc_rdma_result_payload(struct svc_rqst *rqstp, unsigned int offset,
213 				   unsigned int length);
214 
215 /* svc_rdma_transport.c */
216 extern struct svc_xprt_class svc_rdma_class;
217 #ifdef CONFIG_SUNRPC_BACKCHANNEL
218 extern struct svc_xprt_class svc_rdma_bc_class;
219 #endif
220 
221 /* svc_rdma.c */
222 extern int svc_rdma_init(void);
223 extern void svc_rdma_cleanup(void);
224 
225 #endif
226