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 <linux/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 #define RDMA_RESOLVE_TIMEOUT (5000) /* 5 seconds */ 55 #define RDMA_CONNECT_RETRY_MAX (2) /* retries if no listener backlog */ 56 57 /* 58 * Interface Adapter -- one per transport instance 59 */ 60 struct rpcrdma_ia { 61 struct rdma_cm_id *ri_id; 62 struct ib_pd *ri_pd; 63 struct ib_mr *ri_bind_mem; 64 u32 ri_dma_lkey; 65 int ri_have_dma_lkey; 66 struct completion ri_done; 67 int ri_async_rc; 68 enum rpcrdma_memreg ri_memreg_strategy; 69 }; 70 71 /* 72 * RDMA Endpoint -- one per transport instance 73 */ 74 75 struct rpcrdma_ep { 76 atomic_t rep_cqcount; 77 int rep_cqinit; 78 int rep_connected; 79 struct rpcrdma_ia *rep_ia; 80 struct ib_cq *rep_cq; 81 struct ib_qp_init_attr rep_attr; 82 wait_queue_head_t rep_connect_wait; 83 struct ib_sge rep_pad; /* holds zeroed pad */ 84 struct ib_mr *rep_pad_mr; /* holds zeroed pad */ 85 void (*rep_func)(struct rpcrdma_ep *); 86 struct rpc_xprt *rep_xprt; /* for rep_func */ 87 struct rdma_conn_param rep_remote_cma; 88 struct sockaddr_storage rep_remote_addr; 89 }; 90 91 #define INIT_CQCOUNT(ep) atomic_set(&(ep)->rep_cqcount, (ep)->rep_cqinit) 92 #define DECR_CQCOUNT(ep) atomic_sub_return(1, &(ep)->rep_cqcount) 93 94 /* 95 * struct rpcrdma_rep -- this structure encapsulates state required to recv 96 * and complete a reply, asychronously. It needs several pieces of 97 * state: 98 * o recv buffer (posted to provider) 99 * o ib_sge (also donated to provider) 100 * o status of reply (length, success or not) 101 * o bookkeeping state to get run by tasklet (list, etc) 102 * 103 * These are allocated during initialization, per-transport instance; 104 * however, the tasklet execution list itself is global, as it should 105 * always be pretty short. 106 * 107 * N of these are associated with a transport instance, and stored in 108 * struct rpcrdma_buffer. N is the max number of outstanding requests. 109 */ 110 111 /* temporary static scatter/gather max */ 112 #define RPCRDMA_MAX_DATA_SEGS (64) /* max scatter/gather */ 113 #define RPCRDMA_MAX_SEGS (RPCRDMA_MAX_DATA_SEGS + 2) /* head+tail = 2 */ 114 #define MAX_RPCRDMAHDR (\ 115 /* max supported RPC/RDMA header */ \ 116 sizeof(struct rpcrdma_msg) + (2 * sizeof(u32)) + \ 117 (sizeof(struct rpcrdma_read_chunk) * RPCRDMA_MAX_SEGS) + sizeof(u32)) 118 119 struct rpcrdma_buffer; 120 121 struct rpcrdma_rep { 122 unsigned int rr_len; /* actual received reply length */ 123 struct rpcrdma_buffer *rr_buffer; /* home base for this structure */ 124 struct rpc_xprt *rr_xprt; /* needed for request/reply matching */ 125 void (*rr_func)(struct rpcrdma_rep *);/* called by tasklet in softint */ 126 struct list_head rr_list; /* tasklet list */ 127 wait_queue_head_t rr_unbind; /* optional unbind wait */ 128 struct ib_sge rr_iov; /* for posting */ 129 struct ib_mr *rr_handle; /* handle for mem in rr_iov */ 130 char rr_base[MAX_RPCRDMAHDR]; /* minimal inline receive buffer */ 131 }; 132 133 /* 134 * struct rpcrdma_req -- structure central to the request/reply sequence. 135 * 136 * N of these are associated with a transport instance, and stored in 137 * struct rpcrdma_buffer. N is the max number of outstanding requests. 138 * 139 * It includes pre-registered buffer memory for send AND recv. 140 * The recv buffer, however, is not owned by this structure, and 141 * is "donated" to the hardware when a recv is posted. When a 142 * reply is handled, the recv buffer used is given back to the 143 * struct rpcrdma_req associated with the request. 144 * 145 * In addition to the basic memory, this structure includes an array 146 * of iovs for send operations. The reason is that the iovs passed to 147 * ib_post_{send,recv} must not be modified until the work request 148 * completes. 149 * 150 * NOTES: 151 * o RPCRDMA_MAX_SEGS is the max number of addressible chunk elements we 152 * marshal. The number needed varies depending on the iov lists that 153 * are passed to us, the memory registration mode we are in, and if 154 * physical addressing is used, the layout. 155 */ 156 157 struct rpcrdma_mr_seg { /* chunk descriptors */ 158 union { /* chunk memory handles */ 159 struct ib_mr *rl_mr; /* if registered directly */ 160 struct rpcrdma_mw { /* if registered from region */ 161 union { 162 struct ib_mw *mw; 163 struct ib_fmr *fmr; 164 struct { 165 struct ib_fast_reg_page_list *fr_pgl; 166 struct ib_mr *fr_mr; 167 enum { FRMR_IS_INVALID, FRMR_IS_VALID } state; 168 } frmr; 169 } r; 170 struct list_head mw_list; 171 } *rl_mw; 172 } mr_chunk; 173 u64 mr_base; /* registration result */ 174 u32 mr_rkey; /* registration result */ 175 u32 mr_len; /* length of chunk or segment */ 176 int mr_nsegs; /* number of segments in chunk or 0 */ 177 enum dma_data_direction mr_dir; /* segment mapping direction */ 178 dma_addr_t mr_dma; /* segment mapping address */ 179 size_t mr_dmalen; /* segment mapping length */ 180 struct page *mr_page; /* owning page, if any */ 181 char *mr_offset; /* kva if no page, else offset */ 182 }; 183 184 struct rpcrdma_req { 185 size_t rl_size; /* actual length of buffer */ 186 unsigned int rl_niovs; /* 0, 2 or 4 */ 187 unsigned int rl_nchunks; /* non-zero if chunks */ 188 unsigned int rl_connect_cookie; /* retry detection */ 189 struct rpcrdma_buffer *rl_buffer; /* home base for this structure */ 190 struct rpcrdma_rep *rl_reply;/* holder for reply buffer */ 191 struct rpcrdma_mr_seg rl_segments[RPCRDMA_MAX_SEGS];/* chunk segments */ 192 struct ib_sge rl_send_iov[4]; /* for active requests */ 193 struct ib_sge rl_iov; /* for posting */ 194 struct ib_mr *rl_handle; /* handle for mem in rl_iov */ 195 char rl_base[MAX_RPCRDMAHDR]; /* start of actual buffer */ 196 __u32 rl_xdr_buf[0]; /* start of returned rpc rq_buffer */ 197 }; 198 #define rpcr_to_rdmar(r) \ 199 container_of((r)->rq_buffer, struct rpcrdma_req, rl_xdr_buf[0]) 200 201 /* 202 * struct rpcrdma_buffer -- holds list/queue of pre-registered memory for 203 * inline requests/replies, and client/server credits. 204 * 205 * One of these is associated with a transport instance 206 */ 207 struct rpcrdma_buffer { 208 spinlock_t rb_lock; /* protects indexes */ 209 atomic_t rb_credits; /* most recent server credits */ 210 unsigned long rb_cwndscale; /* cached framework rpc_cwndscale */ 211 int rb_max_requests;/* client max requests */ 212 struct list_head rb_mws; /* optional memory windows/fmrs/frmrs */ 213 int rb_send_index; 214 struct rpcrdma_req **rb_send_bufs; 215 int rb_recv_index; 216 struct rpcrdma_rep **rb_recv_bufs; 217 char *rb_pool; 218 }; 219 #define rdmab_to_ia(b) (&container_of((b), struct rpcrdma_xprt, rx_buf)->rx_ia) 220 221 /* 222 * Internal structure for transport instance creation. This 223 * exists primarily for modularity. 224 * 225 * This data should be set with mount options 226 */ 227 struct rpcrdma_create_data_internal { 228 struct sockaddr_storage addr; /* RDMA server address */ 229 unsigned int max_requests; /* max requests (slots) in flight */ 230 unsigned int rsize; /* mount rsize - max read hdr+data */ 231 unsigned int wsize; /* mount wsize - max write hdr+data */ 232 unsigned int inline_rsize; /* max non-rdma read data payload */ 233 unsigned int inline_wsize; /* max non-rdma write data payload */ 234 unsigned int padding; /* non-rdma write header padding */ 235 }; 236 237 #define RPCRDMA_INLINE_READ_THRESHOLD(rq) \ 238 (rpcx_to_rdmad(rq->rq_task->tk_xprt).inline_rsize) 239 240 #define RPCRDMA_INLINE_WRITE_THRESHOLD(rq)\ 241 (rpcx_to_rdmad(rq->rq_task->tk_xprt).inline_wsize) 242 243 #define RPCRDMA_INLINE_PAD_VALUE(rq)\ 244 rpcx_to_rdmad(rq->rq_task->tk_xprt).padding 245 246 /* 247 * Statistics for RPCRDMA 248 */ 249 struct rpcrdma_stats { 250 unsigned long read_chunk_count; 251 unsigned long write_chunk_count; 252 unsigned long reply_chunk_count; 253 254 unsigned long long total_rdma_request; 255 unsigned long long total_rdma_reply; 256 257 unsigned long long pullup_copy_count; 258 unsigned long long fixup_copy_count; 259 unsigned long hardway_register_count; 260 unsigned long failed_marshal_count; 261 unsigned long bad_reply_count; 262 }; 263 264 /* 265 * RPCRDMA transport -- encapsulates the structures above for 266 * integration with RPC. 267 * 268 * The contained structures are embedded, not pointers, 269 * for convenience. This structure need not be visible externally. 270 * 271 * It is allocated and initialized during mount, and released 272 * during unmount. 273 */ 274 struct rpcrdma_xprt { 275 struct rpc_xprt xprt; 276 struct rpcrdma_ia rx_ia; 277 struct rpcrdma_ep rx_ep; 278 struct rpcrdma_buffer rx_buf; 279 struct rpcrdma_create_data_internal rx_data; 280 struct delayed_work rdma_connect; 281 struct rpcrdma_stats rx_stats; 282 }; 283 284 #define rpcx_to_rdmax(x) container_of(x, struct rpcrdma_xprt, xprt) 285 #define rpcx_to_rdmad(x) (rpcx_to_rdmax(x)->rx_data) 286 287 /* Setting this to 0 ensures interoperability with early servers. 288 * Setting this to 1 enhances certain unaligned read/write performance. 289 * Default is 0, see sysctl entry and rpc_rdma.c rpcrdma_convert_iovs() */ 290 extern int xprt_rdma_pad_optimize; 291 292 /* 293 * Interface Adapter calls - xprtrdma/verbs.c 294 */ 295 int rpcrdma_ia_open(struct rpcrdma_xprt *, struct sockaddr *, int); 296 void rpcrdma_ia_close(struct rpcrdma_ia *); 297 298 /* 299 * Endpoint calls - xprtrdma/verbs.c 300 */ 301 int rpcrdma_ep_create(struct rpcrdma_ep *, struct rpcrdma_ia *, 302 struct rpcrdma_create_data_internal *); 303 int rpcrdma_ep_destroy(struct rpcrdma_ep *, struct rpcrdma_ia *); 304 int rpcrdma_ep_connect(struct rpcrdma_ep *, struct rpcrdma_ia *); 305 int rpcrdma_ep_disconnect(struct rpcrdma_ep *, struct rpcrdma_ia *); 306 307 int rpcrdma_ep_post(struct rpcrdma_ia *, struct rpcrdma_ep *, 308 struct rpcrdma_req *); 309 int rpcrdma_ep_post_recv(struct rpcrdma_ia *, struct rpcrdma_ep *, 310 struct rpcrdma_rep *); 311 312 /* 313 * Buffer calls - xprtrdma/verbs.c 314 */ 315 int rpcrdma_buffer_create(struct rpcrdma_buffer *, struct rpcrdma_ep *, 316 struct rpcrdma_ia *, 317 struct rpcrdma_create_data_internal *); 318 void rpcrdma_buffer_destroy(struct rpcrdma_buffer *); 319 320 struct rpcrdma_req *rpcrdma_buffer_get(struct rpcrdma_buffer *); 321 void rpcrdma_buffer_put(struct rpcrdma_req *); 322 void rpcrdma_recv_buffer_get(struct rpcrdma_req *); 323 void rpcrdma_recv_buffer_put(struct rpcrdma_rep *); 324 325 int rpcrdma_register_internal(struct rpcrdma_ia *, void *, int, 326 struct ib_mr **, struct ib_sge *); 327 int rpcrdma_deregister_internal(struct rpcrdma_ia *, 328 struct ib_mr *, struct ib_sge *); 329 330 int rpcrdma_register_external(struct rpcrdma_mr_seg *, 331 int, int, struct rpcrdma_xprt *); 332 int rpcrdma_deregister_external(struct rpcrdma_mr_seg *, 333 struct rpcrdma_xprt *, void *); 334 335 /* 336 * RPC/RDMA connection management calls - xprtrdma/rpc_rdma.c 337 */ 338 void rpcrdma_conn_func(struct rpcrdma_ep *); 339 void rpcrdma_reply_handler(struct rpcrdma_rep *); 340 341 /* 342 * RPC/RDMA protocol calls - xprtrdma/rpc_rdma.c 343 */ 344 int rpcrdma_marshal_req(struct rpc_rqst *); 345 346 /* Temporary NFS request map cache. Created in svc_rdma.c */ 347 extern struct kmem_cache *svc_rdma_map_cachep; 348 /* WR context cache. Created in svc_rdma.c */ 349 extern struct kmem_cache *svc_rdma_ctxt_cachep; 350 /* Workqueue created in svc_rdma.c */ 351 extern struct workqueue_struct *svc_rdma_wq; 352 353 #endif /* _LINUX_SUNRPC_XPRT_RDMA_H */ 354