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/sunrpc/xdr.h>
46 #include <linux/sunrpc/svcsock.h>
47 #include <linux/sunrpc/rpc_rdma.h>
48 #include <rdma/ib_verbs.h>
49 #include <rdma/rdma_cm.h>
50 #define SVCRDMA_DEBUG
51 
52 /* Default and maximum inline threshold sizes */
53 enum {
54 	RPCRDMA_DEF_INLINE_THRESH = 4096,
55 	RPCRDMA_MAX_INLINE_THRESH = 65536
56 };
57 
58 /* RPC/RDMA parameters and stats */
59 extern unsigned int svcrdma_ord;
60 extern unsigned int svcrdma_max_requests;
61 extern unsigned int svcrdma_max_bc_requests;
62 extern unsigned int svcrdma_max_req_size;
63 
64 extern atomic_t rdma_stat_recv;
65 extern atomic_t rdma_stat_read;
66 extern atomic_t rdma_stat_write;
67 extern atomic_t rdma_stat_sq_starve;
68 extern atomic_t rdma_stat_rq_starve;
69 extern atomic_t rdma_stat_rq_poll;
70 extern atomic_t rdma_stat_rq_prod;
71 extern atomic_t rdma_stat_sq_poll;
72 extern atomic_t rdma_stat_sq_prod;
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 list_head     sc_send_ctxts;
94 	spinlock_t	     sc_rw_ctxt_lock;
95 	struct list_head     sc_rw_ctxts;
96 
97 	struct list_head     sc_rq_dto_q;
98 	spinlock_t	     sc_rq_dto_lock;
99 	struct ib_qp         *sc_qp;
100 	struct ib_cq         *sc_rq_cq;
101 	struct ib_cq         *sc_sq_cq;
102 
103 	spinlock_t	     sc_lock;		/* transport lock */
104 
105 	wait_queue_head_t    sc_send_wait;	/* SQ exhaustion waitlist */
106 	unsigned long	     sc_flags;
107 	struct list_head     sc_read_complete_q;
108 	struct work_struct   sc_work;
109 
110 	spinlock_t	     sc_recv_lock;
111 	struct list_head     sc_recv_ctxts;
112 };
113 /* sc_flags */
114 #define RDMAXPRT_CONN_PENDING	3
115 
116 #define RPCRDMA_LISTEN_BACKLOG  10
117 #define RPCRDMA_MAX_REQUESTS    32
118 
119 /* Typical ULP usage of BC requests is NFSv4.1 backchannel. Our
120  * current NFSv4.1 implementation supports one backchannel slot.
121  */
122 #define RPCRDMA_MAX_BC_REQUESTS	2
123 
124 #define RPCSVC_MAXPAYLOAD_RDMA	RPCSVC_MAXPAYLOAD
125 
126 struct svc_rdma_recv_ctxt {
127 	struct list_head	rc_list;
128 	struct ib_recv_wr	rc_recv_wr;
129 	struct ib_cqe		rc_cqe;
130 	struct ib_sge		rc_recv_sge;
131 	void			*rc_recv_buf;
132 	struct xdr_buf		rc_arg;
133 	bool			rc_temp;
134 	u32			rc_byte_len;
135 	unsigned int		rc_page_count;
136 	unsigned int		rc_hdr_count;
137 	struct page		*rc_pages[RPCSVC_MAXPAGES];
138 };
139 
140 struct svc_rdma_send_ctxt {
141 	struct list_head	sc_list;
142 	struct ib_send_wr	sc_send_wr;
143 	struct ib_cqe		sc_cqe;
144 	void			*sc_xprt_buf;
145 	int			sc_page_count;
146 	int			sc_cur_sge_no;
147 	struct page		*sc_pages[RPCSVC_MAXPAGES];
148 	struct ib_sge		sc_sges[];
149 };
150 
151 /* svc_rdma_backchannel.c */
152 extern int svc_rdma_handle_bc_reply(struct rpc_xprt *xprt,
153 				    __be32 *rdma_resp,
154 				    struct xdr_buf *rcvbuf);
155 
156 /* svc_rdma_recvfrom.c */
157 extern void svc_rdma_recv_ctxts_destroy(struct svcxprt_rdma *rdma);
158 extern bool svc_rdma_post_recvs(struct svcxprt_rdma *rdma);
159 extern void svc_rdma_recv_ctxt_put(struct svcxprt_rdma *rdma,
160 				   struct svc_rdma_recv_ctxt *ctxt);
161 extern void svc_rdma_flush_recv_queues(struct svcxprt_rdma *rdma);
162 extern void svc_rdma_release_rqst(struct svc_rqst *rqstp);
163 extern int svc_rdma_recvfrom(struct svc_rqst *);
164 
165 /* svc_rdma_rw.c */
166 extern void svc_rdma_destroy_rw_ctxts(struct svcxprt_rdma *rdma);
167 extern int svc_rdma_recv_read_chunk(struct svcxprt_rdma *rdma,
168 				    struct svc_rqst *rqstp,
169 				    struct svc_rdma_recv_ctxt *head, __be32 *p);
170 extern int svc_rdma_send_write_chunk(struct svcxprt_rdma *rdma,
171 				     __be32 *wr_ch, struct xdr_buf *xdr);
172 extern int svc_rdma_send_reply_chunk(struct svcxprt_rdma *rdma,
173 				     __be32 *rp_ch, bool writelist,
174 				     struct xdr_buf *xdr);
175 
176 /* svc_rdma_sendto.c */
177 extern void svc_rdma_send_ctxts_destroy(struct svcxprt_rdma *rdma);
178 extern struct svc_rdma_send_ctxt *
179 		svc_rdma_send_ctxt_get(struct svcxprt_rdma *rdma);
180 extern void svc_rdma_send_ctxt_put(struct svcxprt_rdma *rdma,
181 				   struct svc_rdma_send_ctxt *ctxt);
182 extern int svc_rdma_send(struct svcxprt_rdma *rdma, struct ib_send_wr *wr);
183 extern void svc_rdma_sync_reply_hdr(struct svcxprt_rdma *rdma,
184 				    struct svc_rdma_send_ctxt *ctxt,
185 				    unsigned int len);
186 extern int svc_rdma_map_reply_msg(struct svcxprt_rdma *rdma,
187 				  struct svc_rdma_send_ctxt *ctxt,
188 				  struct xdr_buf *xdr, __be32 *wr_lst);
189 extern int svc_rdma_sendto(struct svc_rqst *);
190 
191 /* svc_rdma_transport.c */
192 extern int svc_rdma_create_listen(struct svc_serv *, int, struct sockaddr *);
193 extern void svc_sq_reap(struct svcxprt_rdma *);
194 extern void svc_rq_reap(struct svcxprt_rdma *);
195 extern void svc_rdma_prep_reply_hdr(struct svc_rqst *);
196 
197 extern struct svc_xprt_class svc_rdma_class;
198 #ifdef CONFIG_SUNRPC_BACKCHANNEL
199 extern struct svc_xprt_class svc_rdma_bc_class;
200 #endif
201 
202 /* svc_rdma.c */
203 extern struct workqueue_struct *svc_rdma_wq;
204 extern int svc_rdma_init(void);
205 extern void svc_rdma_cleanup(void);
206 
207 #endif
208