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 #include <linux/workqueue.h> /* struct work_struct */ 47 48 #include <rdma/rdma_cm.h> /* RDMA connection api */ 49 #include <rdma/ib_verbs.h> /* RDMA verbs api */ 50 51 #include <linux/sunrpc/clnt.h> /* rpc_xprt */ 52 #include <linux/sunrpc/rpc_rdma.h> /* RPC/RDMA protocol */ 53 #include <linux/sunrpc/xprtrdma.h> /* xprt parameters */ 54 #include <linux/sunrpc/svc.h> /* RPCSVC_MAXPAYLOAD */ 55 56 #define RDMA_RESOLVE_TIMEOUT (5000) /* 5 seconds */ 57 #define RDMA_CONNECT_RETRY_MAX (2) /* retries if no listener backlog */ 58 59 /* 60 * Interface Adapter -- one per transport instance 61 */ 62 struct rpcrdma_ia { 63 rwlock_t ri_qplock; 64 struct rdma_cm_id *ri_id; 65 struct ib_pd *ri_pd; 66 struct ib_mr *ri_bind_mem; 67 u32 ri_dma_lkey; 68 int ri_have_dma_lkey; 69 struct completion ri_done; 70 int ri_async_rc; 71 enum rpcrdma_memreg ri_memreg_strategy; 72 unsigned int ri_max_frmr_depth; 73 struct ib_device_attr ri_devattr; 74 struct ib_qp_attr ri_qp_attr; 75 struct ib_qp_init_attr ri_qp_init_attr; 76 }; 77 78 /* 79 * RDMA Endpoint -- one per transport instance 80 */ 81 82 #define RPCRDMA_WC_BUDGET (128) 83 #define RPCRDMA_POLLSIZE (16) 84 85 struct rpcrdma_ep { 86 atomic_t rep_cqcount; 87 int rep_cqinit; 88 int rep_connected; 89 struct ib_qp_init_attr rep_attr; 90 wait_queue_head_t rep_connect_wait; 91 struct rpcrdma_regbuf *rep_padbuf; 92 struct rdma_conn_param rep_remote_cma; 93 struct sockaddr_storage rep_remote_addr; 94 struct delayed_work rep_connect_worker; 95 struct ib_wc rep_send_wcs[RPCRDMA_POLLSIZE]; 96 struct ib_wc rep_recv_wcs[RPCRDMA_POLLSIZE]; 97 }; 98 99 /* 100 * Force a signaled SEND Work Request every so often, 101 * in case the provider needs to do some housekeeping. 102 */ 103 #define RPCRDMA_MAX_UNSIGNALED_SENDS (32) 104 105 #define INIT_CQCOUNT(ep) atomic_set(&(ep)->rep_cqcount, (ep)->rep_cqinit) 106 #define DECR_CQCOUNT(ep) atomic_sub_return(1, &(ep)->rep_cqcount) 107 108 /* Registered buffer -- registered kmalloc'd memory for RDMA SEND/RECV 109 * 110 * The below structure appears at the front of a large region of kmalloc'd 111 * memory, which always starts on a good alignment boundary. 112 */ 113 114 struct rpcrdma_regbuf { 115 size_t rg_size; 116 struct rpcrdma_req *rg_owner; 117 struct ib_mr *rg_mr; 118 struct ib_sge rg_iov; 119 __be32 rg_base[0] __attribute__ ((aligned(256))); 120 }; 121 122 static inline u64 123 rdmab_addr(struct rpcrdma_regbuf *rb) 124 { 125 return rb->rg_iov.addr; 126 } 127 128 static inline u32 129 rdmab_length(struct rpcrdma_regbuf *rb) 130 { 131 return rb->rg_iov.length; 132 } 133 134 static inline u32 135 rdmab_lkey(struct rpcrdma_regbuf *rb) 136 { 137 return rb->rg_iov.lkey; 138 } 139 140 static inline struct rpcrdma_msg * 141 rdmab_to_msg(struct rpcrdma_regbuf *rb) 142 { 143 return (struct rpcrdma_msg *)rb->rg_base; 144 } 145 146 enum rpcrdma_chunktype { 147 rpcrdma_noch = 0, 148 rpcrdma_readch, 149 rpcrdma_areadch, 150 rpcrdma_writech, 151 rpcrdma_replych 152 }; 153 154 /* 155 * struct rpcrdma_rep -- this structure encapsulates state required to recv 156 * and complete a reply, asychronously. It needs several pieces of 157 * state: 158 * o recv buffer (posted to provider) 159 * o ib_sge (also donated to provider) 160 * o status of reply (length, success or not) 161 * o bookkeeping state to get run by tasklet (list, etc) 162 * 163 * These are allocated during initialization, per-transport instance; 164 * however, the tasklet execution list itself is global, as it should 165 * always be pretty short. 166 * 167 * N of these are associated with a transport instance, and stored in 168 * struct rpcrdma_buffer. N is the max number of outstanding requests. 169 */ 170 171 /* temporary static scatter/gather max */ 172 #define RPCRDMA_MAX_DATA_SEGS (64) /* max scatter/gather */ 173 #define RPCRDMA_MAX_SEGS (RPCRDMA_MAX_DATA_SEGS + 2) /* head+tail = 2 */ 174 175 struct rpcrdma_buffer; 176 177 struct rpcrdma_rep { 178 unsigned int rr_len; 179 struct rpcrdma_buffer *rr_buffer; 180 struct rpc_xprt *rr_xprt; 181 void (*rr_func)(struct rpcrdma_rep *); 182 struct list_head rr_list; 183 struct rpcrdma_regbuf *rr_rdmabuf; 184 }; 185 186 /* 187 * struct rpcrdma_mw - external memory region metadata 188 * 189 * An external memory region is any buffer or page that is registered 190 * on the fly (ie, not pre-registered). 191 * 192 * Each rpcrdma_buffer has a list of free MWs anchored in rb_mws. During 193 * call_allocate, rpcrdma_buffer_get() assigns one to each segment in 194 * an rpcrdma_req. Then rpcrdma_register_external() grabs these to keep 195 * track of registration metadata while each RPC is pending. 196 * rpcrdma_deregister_external() uses this metadata to unmap and 197 * release these resources when an RPC is complete. 198 */ 199 enum rpcrdma_frmr_state { 200 FRMR_IS_INVALID, /* ready to be used */ 201 FRMR_IS_VALID, /* in use */ 202 FRMR_IS_STALE, /* failed completion */ 203 }; 204 205 struct rpcrdma_frmr { 206 struct ib_fast_reg_page_list *fr_pgl; 207 struct ib_mr *fr_mr; 208 enum rpcrdma_frmr_state fr_state; 209 }; 210 211 struct rpcrdma_mw { 212 union { 213 struct ib_fmr *fmr; 214 struct rpcrdma_frmr frmr; 215 } r; 216 struct list_head mw_list; 217 struct list_head mw_all; 218 }; 219 220 /* 221 * struct rpcrdma_req -- structure central to the request/reply sequence. 222 * 223 * N of these are associated with a transport instance, and stored in 224 * struct rpcrdma_buffer. N is the max number of outstanding requests. 225 * 226 * It includes pre-registered buffer memory for send AND recv. 227 * The recv buffer, however, is not owned by this structure, and 228 * is "donated" to the hardware when a recv is posted. When a 229 * reply is handled, the recv buffer used is given back to the 230 * struct rpcrdma_req associated with the request. 231 * 232 * In addition to the basic memory, this structure includes an array 233 * of iovs for send operations. The reason is that the iovs passed to 234 * ib_post_{send,recv} must not be modified until the work request 235 * completes. 236 * 237 * NOTES: 238 * o RPCRDMA_MAX_SEGS is the max number of addressible chunk elements we 239 * marshal. The number needed varies depending on the iov lists that 240 * are passed to us, the memory registration mode we are in, and if 241 * physical addressing is used, the layout. 242 */ 243 244 struct rpcrdma_mr_seg { /* chunk descriptors */ 245 struct rpcrdma_mw *rl_mw; /* registered MR */ 246 u64 mr_base; /* registration result */ 247 u32 mr_rkey; /* registration result */ 248 u32 mr_len; /* length of chunk or segment */ 249 int mr_nsegs; /* number of segments in chunk or 0 */ 250 enum dma_data_direction mr_dir; /* segment mapping direction */ 251 dma_addr_t mr_dma; /* segment mapping address */ 252 size_t mr_dmalen; /* segment mapping length */ 253 struct page *mr_page; /* owning page, if any */ 254 char *mr_offset; /* kva if no page, else offset */ 255 }; 256 257 struct rpcrdma_req { 258 unsigned int rl_niovs; /* 0, 2 or 4 */ 259 unsigned int rl_nchunks; /* non-zero if chunks */ 260 unsigned int rl_connect_cookie; /* retry detection */ 261 enum rpcrdma_chunktype rl_rtype, rl_wtype; 262 struct rpcrdma_buffer *rl_buffer; /* home base for this structure */ 263 struct rpcrdma_rep *rl_reply;/* holder for reply buffer */ 264 struct ib_sge rl_send_iov[4]; /* for active requests */ 265 struct rpcrdma_regbuf *rl_rdmabuf; 266 struct rpcrdma_regbuf *rl_sendbuf; 267 struct rpcrdma_mr_seg rl_segments[RPCRDMA_MAX_SEGS]; 268 }; 269 270 static inline struct rpcrdma_req * 271 rpcr_to_rdmar(struct rpc_rqst *rqst) 272 { 273 void *buffer = rqst->rq_buffer; 274 struct rpcrdma_regbuf *rb; 275 276 rb = container_of(buffer, struct rpcrdma_regbuf, rg_base); 277 return rb->rg_owner; 278 } 279 280 /* 281 * struct rpcrdma_buffer -- holds list/queue of pre-registered memory for 282 * inline requests/replies, and client/server credits. 283 * 284 * One of these is associated with a transport instance 285 */ 286 struct rpcrdma_buffer { 287 spinlock_t rb_lock; /* protects indexes */ 288 int rb_max_requests;/* client max requests */ 289 struct list_head rb_mws; /* optional memory windows/fmrs/frmrs */ 290 struct list_head rb_all; 291 int rb_send_index; 292 struct rpcrdma_req **rb_send_bufs; 293 int rb_recv_index; 294 struct rpcrdma_rep **rb_recv_bufs; 295 char *rb_pool; 296 }; 297 #define rdmab_to_ia(b) (&container_of((b), struct rpcrdma_xprt, rx_buf)->rx_ia) 298 299 /* 300 * Internal structure for transport instance creation. This 301 * exists primarily for modularity. 302 * 303 * This data should be set with mount options 304 */ 305 struct rpcrdma_create_data_internal { 306 struct sockaddr_storage addr; /* RDMA server address */ 307 unsigned int max_requests; /* max requests (slots) in flight */ 308 unsigned int rsize; /* mount rsize - max read hdr+data */ 309 unsigned int wsize; /* mount wsize - max write hdr+data */ 310 unsigned int inline_rsize; /* max non-rdma read data payload */ 311 unsigned int inline_wsize; /* max non-rdma write data payload */ 312 unsigned int padding; /* non-rdma write header padding */ 313 }; 314 315 #define RPCRDMA_INLINE_READ_THRESHOLD(rq) \ 316 (rpcx_to_rdmad(rq->rq_xprt).inline_rsize) 317 318 #define RPCRDMA_INLINE_WRITE_THRESHOLD(rq)\ 319 (rpcx_to_rdmad(rq->rq_xprt).inline_wsize) 320 321 #define RPCRDMA_INLINE_PAD_VALUE(rq)\ 322 rpcx_to_rdmad(rq->rq_xprt).padding 323 324 /* 325 * Statistics for RPCRDMA 326 */ 327 struct rpcrdma_stats { 328 unsigned long read_chunk_count; 329 unsigned long write_chunk_count; 330 unsigned long reply_chunk_count; 331 332 unsigned long long total_rdma_request; 333 unsigned long long total_rdma_reply; 334 335 unsigned long long pullup_copy_count; 336 unsigned long long fixup_copy_count; 337 unsigned long hardway_register_count; 338 unsigned long failed_marshal_count; 339 unsigned long bad_reply_count; 340 }; 341 342 /* 343 * RPCRDMA transport -- encapsulates the structures above for 344 * integration with RPC. 345 * 346 * The contained structures are embedded, not pointers, 347 * for convenience. This structure need not be visible externally. 348 * 349 * It is allocated and initialized during mount, and released 350 * during unmount. 351 */ 352 struct rpcrdma_xprt { 353 struct rpc_xprt rx_xprt; 354 struct rpcrdma_ia rx_ia; 355 struct rpcrdma_ep rx_ep; 356 struct rpcrdma_buffer rx_buf; 357 struct rpcrdma_create_data_internal rx_data; 358 struct delayed_work rx_connect_worker; 359 struct rpcrdma_stats rx_stats; 360 }; 361 362 #define rpcx_to_rdmax(x) container_of(x, struct rpcrdma_xprt, rx_xprt) 363 #define rpcx_to_rdmad(x) (rpcx_to_rdmax(x)->rx_data) 364 365 /* Setting this to 0 ensures interoperability with early servers. 366 * Setting this to 1 enhances certain unaligned read/write performance. 367 * Default is 0, see sysctl entry and rpc_rdma.c rpcrdma_convert_iovs() */ 368 extern int xprt_rdma_pad_optimize; 369 370 /* 371 * Interface Adapter calls - xprtrdma/verbs.c 372 */ 373 int rpcrdma_ia_open(struct rpcrdma_xprt *, struct sockaddr *, int); 374 void rpcrdma_ia_close(struct rpcrdma_ia *); 375 376 /* 377 * Endpoint calls - xprtrdma/verbs.c 378 */ 379 int rpcrdma_ep_create(struct rpcrdma_ep *, struct rpcrdma_ia *, 380 struct rpcrdma_create_data_internal *); 381 void rpcrdma_ep_destroy(struct rpcrdma_ep *, struct rpcrdma_ia *); 382 int rpcrdma_ep_connect(struct rpcrdma_ep *, struct rpcrdma_ia *); 383 void rpcrdma_ep_disconnect(struct rpcrdma_ep *, struct rpcrdma_ia *); 384 385 int rpcrdma_ep_post(struct rpcrdma_ia *, struct rpcrdma_ep *, 386 struct rpcrdma_req *); 387 int rpcrdma_ep_post_recv(struct rpcrdma_ia *, struct rpcrdma_ep *, 388 struct rpcrdma_rep *); 389 390 /* 391 * Buffer calls - xprtrdma/verbs.c 392 */ 393 int rpcrdma_buffer_create(struct rpcrdma_xprt *); 394 void rpcrdma_buffer_destroy(struct rpcrdma_buffer *); 395 396 struct rpcrdma_req *rpcrdma_buffer_get(struct rpcrdma_buffer *); 397 void rpcrdma_buffer_put(struct rpcrdma_req *); 398 void rpcrdma_recv_buffer_get(struct rpcrdma_req *); 399 void rpcrdma_recv_buffer_put(struct rpcrdma_rep *); 400 401 int rpcrdma_register_external(struct rpcrdma_mr_seg *, 402 int, int, struct rpcrdma_xprt *); 403 int rpcrdma_deregister_external(struct rpcrdma_mr_seg *, 404 struct rpcrdma_xprt *); 405 406 struct rpcrdma_regbuf *rpcrdma_alloc_regbuf(struct rpcrdma_ia *, 407 size_t, gfp_t); 408 void rpcrdma_free_regbuf(struct rpcrdma_ia *, 409 struct rpcrdma_regbuf *); 410 411 /* 412 * RPC/RDMA connection management calls - xprtrdma/rpc_rdma.c 413 */ 414 void rpcrdma_connect_worker(struct work_struct *); 415 void rpcrdma_conn_func(struct rpcrdma_ep *); 416 void rpcrdma_reply_handler(struct rpcrdma_rep *); 417 418 /* 419 * RPC/RDMA protocol calls - xprtrdma/rpc_rdma.c 420 */ 421 ssize_t rpcrdma_marshal_chunks(struct rpc_rqst *, ssize_t); 422 int rpcrdma_marshal_req(struct rpc_rqst *); 423 size_t rpcrdma_max_payload(struct rpcrdma_xprt *); 424 425 /* Temporary NFS request map cache. Created in svc_rdma.c */ 426 extern struct kmem_cache *svc_rdma_map_cachep; 427 /* WR context cache. Created in svc_rdma.c */ 428 extern struct kmem_cache *svc_rdma_ctxt_cachep; 429 /* Workqueue created in svc_rdma.c */ 430 extern struct workqueue_struct *svc_rdma_wq; 431 432 #if RPCSVC_MAXPAYLOAD < (RPCRDMA_MAX_DATA_SEGS << PAGE_SHIFT) 433 #define RPCSVC_MAXPAYLOAD_RDMA RPCSVC_MAXPAYLOAD 434 #else 435 #define RPCSVC_MAXPAYLOAD_RDMA (RPCRDMA_MAX_DATA_SEGS << PAGE_SHIFT) 436 #endif 437 438 #endif /* _LINUX_SUNRPC_XPRT_RDMA_H */ 439