1 /* 2 * Copyright (c) 2003-2007 Network Appliance, Inc. All rights reserved. 3 * 4 * This software is available to you under a choice of one of two 5 * licenses. You may choose to be licensed under the terms of the GNU 6 * General Public License (GPL) Version 2, available from the file 7 * COPYING in the main directory of this source tree, or the BSD-type 8 * license below: 9 * 10 * Redistribution and use in source and binary forms, with or without 11 * modification, are permitted provided that the following conditions 12 * are met: 13 * 14 * Redistributions of source code must retain the above copyright 15 * notice, this list of conditions and the following disclaimer. 16 * 17 * Redistributions in binary form must reproduce the above 18 * copyright notice, this list of conditions and the following 19 * disclaimer in the documentation and/or other materials provided 20 * with the distribution. 21 * 22 * Neither the name of the Network Appliance, Inc. nor the names of 23 * its contributors may be used to endorse or promote products 24 * derived from this software without specific prior written 25 * permission. 26 * 27 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS 28 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT 29 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR 30 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT 31 * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, 32 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT 33 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 34 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 35 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 36 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE 37 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 38 */ 39 40 #ifndef _LINUX_SUNRPC_XPRT_RDMA_H 41 #define _LINUX_SUNRPC_XPRT_RDMA_H 42 43 #include <linux/wait.h> /* wait_queue_head_t, etc */ 44 #include <linux/spinlock.h> /* spinlock_t, etc */ 45 #include <asm/atomic.h> /* atomic_t, etc */ 46 47 #include <rdma/rdma_cm.h> /* RDMA connection api */ 48 #include <rdma/ib_verbs.h> /* RDMA verbs api */ 49 50 #include <linux/sunrpc/clnt.h> /* rpc_xprt */ 51 #include <linux/sunrpc/rpc_rdma.h> /* RPC/RDMA protocol */ 52 #include <linux/sunrpc/xprtrdma.h> /* xprt parameters */ 53 54 /* 55 * Interface Adapter -- one per transport instance 56 */ 57 struct rpcrdma_ia { 58 struct rdma_cm_id *ri_id; 59 struct ib_pd *ri_pd; 60 struct ib_mr *ri_bind_mem; 61 struct completion ri_done; 62 int ri_async_rc; 63 enum rpcrdma_memreg ri_memreg_strategy; 64 }; 65 66 /* 67 * RDMA Endpoint -- one per transport instance 68 */ 69 70 struct rpcrdma_ep { 71 atomic_t rep_cqcount; 72 int rep_cqinit; 73 int rep_connected; 74 struct rpcrdma_ia *rep_ia; 75 struct ib_cq *rep_cq; 76 struct ib_qp_init_attr rep_attr; 77 wait_queue_head_t rep_connect_wait; 78 struct ib_sge rep_pad; /* holds zeroed pad */ 79 struct ib_mr *rep_pad_mr; /* holds zeroed pad */ 80 void (*rep_func)(struct rpcrdma_ep *); 81 struct rpc_xprt *rep_xprt; /* for rep_func */ 82 struct rdma_conn_param rep_remote_cma; 83 struct sockaddr_storage rep_remote_addr; 84 }; 85 86 #define INIT_CQCOUNT(ep) atomic_set(&(ep)->rep_cqcount, (ep)->rep_cqinit) 87 #define DECR_CQCOUNT(ep) atomic_sub_return(1, &(ep)->rep_cqcount) 88 89 /* 90 * struct rpcrdma_rep -- this structure encapsulates state required to recv 91 * and complete a reply, asychronously. It needs several pieces of 92 * state: 93 * o recv buffer (posted to provider) 94 * o ib_sge (also donated to provider) 95 * o status of reply (length, success or not) 96 * o bookkeeping state to get run by tasklet (list, etc) 97 * 98 * These are allocated during initialization, per-transport instance; 99 * however, the tasklet execution list itself is global, as it should 100 * always be pretty short. 101 * 102 * N of these are associated with a transport instance, and stored in 103 * struct rpcrdma_buffer. N is the max number of outstanding requests. 104 */ 105 106 /* temporary static scatter/gather max */ 107 #define RPCRDMA_MAX_DATA_SEGS (8) /* max scatter/gather */ 108 #define RPCRDMA_MAX_SEGS (RPCRDMA_MAX_DATA_SEGS + 2) /* head+tail = 2 */ 109 #define MAX_RPCRDMAHDR (\ 110 /* max supported RPC/RDMA header */ \ 111 sizeof(struct rpcrdma_msg) + (2 * sizeof(u32)) + \ 112 (sizeof(struct rpcrdma_read_chunk) * RPCRDMA_MAX_SEGS) + sizeof(u32)) 113 114 struct rpcrdma_buffer; 115 116 struct rpcrdma_rep { 117 unsigned int rr_len; /* actual received reply length */ 118 struct rpcrdma_buffer *rr_buffer; /* home base for this structure */ 119 struct rpc_xprt *rr_xprt; /* needed for request/reply matching */ 120 void (*rr_func)(struct rpcrdma_rep *);/* called by tasklet in softint */ 121 struct list_head rr_list; /* tasklet list */ 122 wait_queue_head_t rr_unbind; /* optional unbind wait */ 123 struct ib_sge rr_iov; /* for posting */ 124 struct ib_mr *rr_handle; /* handle for mem in rr_iov */ 125 char rr_base[MAX_RPCRDMAHDR]; /* minimal inline receive buffer */ 126 }; 127 128 /* 129 * struct rpcrdma_req -- structure central to the request/reply sequence. 130 * 131 * N of these are associated with a transport instance, and stored in 132 * struct rpcrdma_buffer. N is the max number of outstanding requests. 133 * 134 * It includes pre-registered buffer memory for send AND recv. 135 * The recv buffer, however, is not owned by this structure, and 136 * is "donated" to the hardware when a recv is posted. When a 137 * reply is handled, the recv buffer used is given back to the 138 * struct rpcrdma_req associated with the request. 139 * 140 * In addition to the basic memory, this structure includes an array 141 * of iovs for send operations. The reason is that the iovs passed to 142 * ib_post_{send,recv} must not be modified until the work request 143 * completes. 144 * 145 * NOTES: 146 * o RPCRDMA_MAX_SEGS is the max number of addressible chunk elements we 147 * marshal. The number needed varies depending on the iov lists that 148 * are passed to us, the memory registration mode we are in, and if 149 * physical addressing is used, the layout. 150 */ 151 152 struct rpcrdma_mr_seg { /* chunk descriptors */ 153 union { /* chunk memory handles */ 154 struct ib_mr *rl_mr; /* if registered directly */ 155 struct rpcrdma_mw { /* if registered from region */ 156 union { 157 struct ib_mw *mw; 158 struct ib_fmr *fmr; 159 } r; 160 struct list_head mw_list; 161 } *rl_mw; 162 } mr_chunk; 163 u64 mr_base; /* registration result */ 164 u32 mr_rkey; /* registration result */ 165 u32 mr_len; /* length of chunk or segment */ 166 int mr_nsegs; /* number of segments in chunk or 0 */ 167 enum dma_data_direction mr_dir; /* segment mapping direction */ 168 dma_addr_t mr_dma; /* segment mapping address */ 169 size_t mr_dmalen; /* segment mapping length */ 170 struct page *mr_page; /* owning page, if any */ 171 char *mr_offset; /* kva if no page, else offset */ 172 }; 173 174 struct rpcrdma_req { 175 size_t rl_size; /* actual length of buffer */ 176 unsigned int rl_niovs; /* 0, 2 or 4 */ 177 unsigned int rl_nchunks; /* non-zero if chunks */ 178 struct rpcrdma_buffer *rl_buffer; /* home base for this structure */ 179 struct rpcrdma_rep *rl_reply;/* holder for reply buffer */ 180 struct rpcrdma_mr_seg rl_segments[RPCRDMA_MAX_SEGS];/* chunk segments */ 181 struct ib_sge rl_send_iov[4]; /* for active requests */ 182 struct ib_sge rl_iov; /* for posting */ 183 struct ib_mr *rl_handle; /* handle for mem in rl_iov */ 184 char rl_base[MAX_RPCRDMAHDR]; /* start of actual buffer */ 185 __u32 rl_xdr_buf[0]; /* start of returned rpc rq_buffer */ 186 }; 187 #define rpcr_to_rdmar(r) \ 188 container_of((r)->rq_buffer, struct rpcrdma_req, rl_xdr_buf[0]) 189 190 /* 191 * struct rpcrdma_buffer -- holds list/queue of pre-registered memory for 192 * inline requests/replies, and client/server credits. 193 * 194 * One of these is associated with a transport instance 195 */ 196 struct rpcrdma_buffer { 197 spinlock_t rb_lock; /* protects indexes */ 198 atomic_t rb_credits; /* most recent server credits */ 199 unsigned long rb_cwndscale; /* cached framework rpc_cwndscale */ 200 int rb_max_requests;/* client max requests */ 201 struct list_head rb_mws; /* optional memory windows/fmrs */ 202 int rb_send_index; 203 struct rpcrdma_req **rb_send_bufs; 204 int rb_recv_index; 205 struct rpcrdma_rep **rb_recv_bufs; 206 char *rb_pool; 207 }; 208 #define rdmab_to_ia(b) (&container_of((b), struct rpcrdma_xprt, rx_buf)->rx_ia) 209 210 /* 211 * Internal structure for transport instance creation. This 212 * exists primarily for modularity. 213 * 214 * This data should be set with mount options 215 */ 216 struct rpcrdma_create_data_internal { 217 struct sockaddr_storage addr; /* RDMA server address */ 218 unsigned int max_requests; /* max requests (slots) in flight */ 219 unsigned int rsize; /* mount rsize - max read hdr+data */ 220 unsigned int wsize; /* mount wsize - max write hdr+data */ 221 unsigned int inline_rsize; /* max non-rdma read data payload */ 222 unsigned int inline_wsize; /* max non-rdma write data payload */ 223 unsigned int padding; /* non-rdma write header padding */ 224 }; 225 226 #define RPCRDMA_INLINE_READ_THRESHOLD(rq) \ 227 (rpcx_to_rdmad(rq->rq_task->tk_xprt).inline_rsize) 228 229 #define RPCRDMA_INLINE_WRITE_THRESHOLD(rq)\ 230 (rpcx_to_rdmad(rq->rq_task->tk_xprt).inline_wsize) 231 232 #define RPCRDMA_INLINE_PAD_VALUE(rq)\ 233 rpcx_to_rdmad(rq->rq_task->tk_xprt).padding 234 235 /* 236 * Statistics for RPCRDMA 237 */ 238 struct rpcrdma_stats { 239 unsigned long read_chunk_count; 240 unsigned long write_chunk_count; 241 unsigned long reply_chunk_count; 242 243 unsigned long long total_rdma_request; 244 unsigned long long total_rdma_reply; 245 246 unsigned long long pullup_copy_count; 247 unsigned long long fixup_copy_count; 248 unsigned long hardway_register_count; 249 unsigned long failed_marshal_count; 250 unsigned long bad_reply_count; 251 }; 252 253 /* 254 * RPCRDMA transport -- encapsulates the structures above for 255 * integration with RPC. 256 * 257 * The contained structures are embedded, not pointers, 258 * for convenience. This structure need not be visible externally. 259 * 260 * It is allocated and initialized during mount, and released 261 * during unmount. 262 */ 263 struct rpcrdma_xprt { 264 struct rpc_xprt xprt; 265 struct rpcrdma_ia rx_ia; 266 struct rpcrdma_ep rx_ep; 267 struct rpcrdma_buffer rx_buf; 268 struct rpcrdma_create_data_internal rx_data; 269 struct delayed_work rdma_connect; 270 struct rpcrdma_stats rx_stats; 271 }; 272 273 #define rpcx_to_rdmax(x) container_of(x, struct rpcrdma_xprt, xprt) 274 #define rpcx_to_rdmad(x) (rpcx_to_rdmax(x)->rx_data) 275 276 /* 277 * Interface Adapter calls - xprtrdma/verbs.c 278 */ 279 int rpcrdma_ia_open(struct rpcrdma_xprt *, struct sockaddr *, int); 280 void rpcrdma_ia_close(struct rpcrdma_ia *); 281 282 /* 283 * Endpoint calls - xprtrdma/verbs.c 284 */ 285 int rpcrdma_ep_create(struct rpcrdma_ep *, struct rpcrdma_ia *, 286 struct rpcrdma_create_data_internal *); 287 int rpcrdma_ep_destroy(struct rpcrdma_ep *, struct rpcrdma_ia *); 288 int rpcrdma_ep_connect(struct rpcrdma_ep *, struct rpcrdma_ia *); 289 int rpcrdma_ep_disconnect(struct rpcrdma_ep *, struct rpcrdma_ia *); 290 291 int rpcrdma_ep_post(struct rpcrdma_ia *, struct rpcrdma_ep *, 292 struct rpcrdma_req *); 293 int rpcrdma_ep_post_recv(struct rpcrdma_ia *, struct rpcrdma_ep *, 294 struct rpcrdma_rep *); 295 296 /* 297 * Buffer calls - xprtrdma/verbs.c 298 */ 299 int rpcrdma_buffer_create(struct rpcrdma_buffer *, struct rpcrdma_ep *, 300 struct rpcrdma_ia *, 301 struct rpcrdma_create_data_internal *); 302 void rpcrdma_buffer_destroy(struct rpcrdma_buffer *); 303 304 struct rpcrdma_req *rpcrdma_buffer_get(struct rpcrdma_buffer *); 305 void rpcrdma_buffer_put(struct rpcrdma_req *); 306 void rpcrdma_recv_buffer_get(struct rpcrdma_req *); 307 void rpcrdma_recv_buffer_put(struct rpcrdma_rep *); 308 309 int rpcrdma_register_internal(struct rpcrdma_ia *, void *, int, 310 struct ib_mr **, struct ib_sge *); 311 int rpcrdma_deregister_internal(struct rpcrdma_ia *, 312 struct ib_mr *, struct ib_sge *); 313 314 int rpcrdma_register_external(struct rpcrdma_mr_seg *, 315 int, int, struct rpcrdma_xprt *); 316 int rpcrdma_deregister_external(struct rpcrdma_mr_seg *, 317 struct rpcrdma_xprt *, void *); 318 319 /* 320 * RPC/RDMA connection management calls - xprtrdma/rpc_rdma.c 321 */ 322 void rpcrdma_conn_func(struct rpcrdma_ep *); 323 void rpcrdma_reply_handler(struct rpcrdma_rep *); 324 325 /* 326 * RPC/RDMA protocol calls - xprtrdma/rpc_rdma.c 327 */ 328 int rpcrdma_marshal_req(struct rpc_rqst *); 329 330 #endif /* _LINUX_SUNRPC_XPRT_RDMA_H */ 331