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 const struct rpcrdma_memreg_ops *ri_ops; 64 rwlock_t ri_qplock; 65 struct rdma_cm_id *ri_id; 66 struct ib_pd *ri_pd; 67 struct ib_mr *ri_bind_mem; 68 u32 ri_dma_lkey; 69 int ri_have_dma_lkey; 70 struct completion ri_done; 71 int ri_async_rc; 72 enum rpcrdma_memreg ri_memreg_strategy; 73 unsigned int ri_max_frmr_depth; 74 struct ib_device_attr ri_devattr; 75 struct ib_qp_attr ri_qp_attr; 76 struct ib_qp_init_attr ri_qp_init_attr; 77 }; 78 79 /* 80 * RDMA Endpoint -- one per transport instance 81 */ 82 83 #define RPCRDMA_WC_BUDGET (128) 84 #define RPCRDMA_POLLSIZE (16) 85 86 struct rpcrdma_ep { 87 atomic_t rep_cqcount; 88 int rep_cqinit; 89 int rep_connected; 90 struct ib_qp_init_attr rep_attr; 91 wait_queue_head_t rep_connect_wait; 92 struct rpcrdma_regbuf *rep_padbuf; 93 struct rdma_conn_param rep_remote_cma; 94 struct sockaddr_storage rep_remote_addr; 95 struct delayed_work rep_connect_worker; 96 struct ib_wc rep_send_wcs[RPCRDMA_POLLSIZE]; 97 struct ib_wc rep_recv_wcs[RPCRDMA_POLLSIZE]; 98 }; 99 100 /* 101 * Force a signaled SEND Work Request every so often, 102 * in case the provider needs to do some housekeeping. 103 */ 104 #define RPCRDMA_MAX_UNSIGNALED_SENDS (32) 105 106 #define INIT_CQCOUNT(ep) atomic_set(&(ep)->rep_cqcount, (ep)->rep_cqinit) 107 #define DECR_CQCOUNT(ep) atomic_sub_return(1, &(ep)->rep_cqcount) 108 109 /* Force completion handler to ignore the signal 110 */ 111 #define RPCRDMA_IGNORE_COMPLETION (0ULL) 112 113 /* Registered buffer -- registered kmalloc'd memory for RDMA SEND/RECV 114 * 115 * The below structure appears at the front of a large region of kmalloc'd 116 * memory, which always starts on a good alignment boundary. 117 */ 118 119 struct rpcrdma_regbuf { 120 size_t rg_size; 121 struct rpcrdma_req *rg_owner; 122 struct ib_mr *rg_mr; 123 struct ib_sge rg_iov; 124 __be32 rg_base[0] __attribute__ ((aligned(256))); 125 }; 126 127 static inline u64 128 rdmab_addr(struct rpcrdma_regbuf *rb) 129 { 130 return rb->rg_iov.addr; 131 } 132 133 static inline u32 134 rdmab_length(struct rpcrdma_regbuf *rb) 135 { 136 return rb->rg_iov.length; 137 } 138 139 static inline u32 140 rdmab_lkey(struct rpcrdma_regbuf *rb) 141 { 142 return rb->rg_iov.lkey; 143 } 144 145 static inline struct rpcrdma_msg * 146 rdmab_to_msg(struct rpcrdma_regbuf *rb) 147 { 148 return (struct rpcrdma_msg *)rb->rg_base; 149 } 150 151 /* 152 * struct rpcrdma_rep -- this structure encapsulates state required to recv 153 * and complete a reply, asychronously. It needs several pieces of 154 * state: 155 * o recv buffer (posted to provider) 156 * o ib_sge (also donated to provider) 157 * o status of reply (length, success or not) 158 * o bookkeeping state to get run by tasklet (list, etc) 159 * 160 * These are allocated during initialization, per-transport instance; 161 * however, the tasklet execution list itself is global, as it should 162 * always be pretty short. 163 * 164 * N of these are associated with a transport instance, and stored in 165 * struct rpcrdma_buffer. N is the max number of outstanding requests. 166 */ 167 168 /* temporary static scatter/gather max */ 169 #define RPCRDMA_MAX_DATA_SEGS (64) /* max scatter/gather */ 170 #define RPCRDMA_MAX_SEGS (RPCRDMA_MAX_DATA_SEGS + 2) /* head+tail = 2 */ 171 172 struct rpcrdma_buffer; 173 174 struct rpcrdma_rep { 175 unsigned int rr_len; 176 struct rpcrdma_buffer *rr_buffer; 177 struct rpc_xprt *rr_xprt; 178 void (*rr_func)(struct rpcrdma_rep *); 179 struct list_head rr_list; 180 struct rpcrdma_regbuf *rr_rdmabuf; 181 }; 182 183 /* 184 * struct rpcrdma_mw - external memory region metadata 185 * 186 * An external memory region is any buffer or page that is registered 187 * on the fly (ie, not pre-registered). 188 * 189 * Each rpcrdma_buffer has a list of free MWs anchored in rb_mws. During 190 * call_allocate, rpcrdma_buffer_get() assigns one to each segment in 191 * an rpcrdma_req. Then rpcrdma_register_external() grabs these to keep 192 * track of registration metadata while each RPC is pending. 193 * rpcrdma_deregister_external() uses this metadata to unmap and 194 * release these resources when an RPC is complete. 195 */ 196 enum rpcrdma_frmr_state { 197 FRMR_IS_INVALID, /* ready to be used */ 198 FRMR_IS_VALID, /* in use */ 199 FRMR_IS_STALE, /* failed completion */ 200 }; 201 202 struct rpcrdma_frmr { 203 struct ib_fast_reg_page_list *fr_pgl; 204 struct ib_mr *fr_mr; 205 enum rpcrdma_frmr_state fr_state; 206 }; 207 208 struct rpcrdma_mw { 209 union { 210 struct ib_fmr *fmr; 211 struct rpcrdma_frmr frmr; 212 } r; 213 void (*mw_sendcompletion)(struct ib_wc *); 214 struct list_head mw_list; 215 struct list_head mw_all; 216 }; 217 218 /* 219 * struct rpcrdma_req -- structure central to the request/reply sequence. 220 * 221 * N of these are associated with a transport instance, and stored in 222 * struct rpcrdma_buffer. N is the max number of outstanding requests. 223 * 224 * It includes pre-registered buffer memory for send AND recv. 225 * The recv buffer, however, is not owned by this structure, and 226 * is "donated" to the hardware when a recv is posted. When a 227 * reply is handled, the recv buffer used is given back to the 228 * struct rpcrdma_req associated with the request. 229 * 230 * In addition to the basic memory, this structure includes an array 231 * of iovs for send operations. The reason is that the iovs passed to 232 * ib_post_{send,recv} must not be modified until the work request 233 * completes. 234 * 235 * NOTES: 236 * o RPCRDMA_MAX_SEGS is the max number of addressible chunk elements we 237 * marshal. The number needed varies depending on the iov lists that 238 * are passed to us, the memory registration mode we are in, and if 239 * physical addressing is used, the layout. 240 */ 241 242 struct rpcrdma_mr_seg { /* chunk descriptors */ 243 struct rpcrdma_mw *rl_mw; /* registered MR */ 244 u64 mr_base; /* registration result */ 245 u32 mr_rkey; /* registration result */ 246 u32 mr_len; /* length of chunk or segment */ 247 int mr_nsegs; /* number of segments in chunk or 0 */ 248 enum dma_data_direction mr_dir; /* segment mapping direction */ 249 dma_addr_t mr_dma; /* segment mapping address */ 250 size_t mr_dmalen; /* segment mapping length */ 251 struct page *mr_page; /* owning page, if any */ 252 char *mr_offset; /* kva if no page, else offset */ 253 }; 254 255 struct rpcrdma_req { 256 unsigned int rl_niovs; /* 0, 2 or 4 */ 257 unsigned int rl_nchunks; /* non-zero if chunks */ 258 unsigned int rl_connect_cookie; /* retry detection */ 259 struct rpcrdma_buffer *rl_buffer; /* home base for this structure */ 260 struct rpcrdma_rep *rl_reply;/* holder for reply buffer */ 261 struct ib_sge rl_send_iov[4]; /* for active requests */ 262 struct rpcrdma_regbuf *rl_rdmabuf; 263 struct rpcrdma_regbuf *rl_sendbuf; 264 struct rpcrdma_mr_seg rl_segments[RPCRDMA_MAX_SEGS]; 265 }; 266 267 static inline struct rpcrdma_req * 268 rpcr_to_rdmar(struct rpc_rqst *rqst) 269 { 270 void *buffer = rqst->rq_buffer; 271 struct rpcrdma_regbuf *rb; 272 273 rb = container_of(buffer, struct rpcrdma_regbuf, rg_base); 274 return rb->rg_owner; 275 } 276 277 /* 278 * struct rpcrdma_buffer -- holds list/queue of pre-registered memory for 279 * inline requests/replies, and client/server credits. 280 * 281 * One of these is associated with a transport instance 282 */ 283 struct rpcrdma_buffer { 284 spinlock_t rb_lock; /* protects indexes */ 285 u32 rb_max_requests;/* client max requests */ 286 struct list_head rb_mws; /* optional memory windows/fmrs/frmrs */ 287 struct list_head rb_all; 288 int rb_send_index; 289 struct rpcrdma_req **rb_send_bufs; 290 int rb_recv_index; 291 struct rpcrdma_rep **rb_recv_bufs; 292 char *rb_pool; 293 }; 294 #define rdmab_to_ia(b) (&container_of((b), struct rpcrdma_xprt, rx_buf)->rx_ia) 295 296 /* 297 * Internal structure for transport instance creation. This 298 * exists primarily for modularity. 299 * 300 * This data should be set with mount options 301 */ 302 struct rpcrdma_create_data_internal { 303 struct sockaddr_storage addr; /* RDMA server address */ 304 unsigned int max_requests; /* max requests (slots) in flight */ 305 unsigned int rsize; /* mount rsize - max read hdr+data */ 306 unsigned int wsize; /* mount wsize - max write hdr+data */ 307 unsigned int inline_rsize; /* max non-rdma read data payload */ 308 unsigned int inline_wsize; /* max non-rdma write data payload */ 309 unsigned int padding; /* non-rdma write header padding */ 310 }; 311 312 #define RPCRDMA_INLINE_READ_THRESHOLD(rq) \ 313 (rpcx_to_rdmad(rq->rq_xprt).inline_rsize) 314 315 #define RPCRDMA_INLINE_WRITE_THRESHOLD(rq)\ 316 (rpcx_to_rdmad(rq->rq_xprt).inline_wsize) 317 318 #define RPCRDMA_INLINE_PAD_VALUE(rq)\ 319 rpcx_to_rdmad(rq->rq_xprt).padding 320 321 /* 322 * Statistics for RPCRDMA 323 */ 324 struct rpcrdma_stats { 325 unsigned long read_chunk_count; 326 unsigned long write_chunk_count; 327 unsigned long reply_chunk_count; 328 329 unsigned long long total_rdma_request; 330 unsigned long long total_rdma_reply; 331 332 unsigned long long pullup_copy_count; 333 unsigned long long fixup_copy_count; 334 unsigned long hardway_register_count; 335 unsigned long failed_marshal_count; 336 unsigned long bad_reply_count; 337 }; 338 339 /* 340 * Per-registration mode operations 341 */ 342 struct rpcrdma_xprt; 343 struct rpcrdma_memreg_ops { 344 int (*ro_map)(struct rpcrdma_xprt *, 345 struct rpcrdma_mr_seg *, int, bool); 346 int (*ro_unmap)(struct rpcrdma_xprt *, 347 struct rpcrdma_mr_seg *); 348 int (*ro_open)(struct rpcrdma_ia *, 349 struct rpcrdma_ep *, 350 struct rpcrdma_create_data_internal *); 351 size_t (*ro_maxpages)(struct rpcrdma_xprt *); 352 int (*ro_init)(struct rpcrdma_xprt *); 353 void (*ro_reset)(struct rpcrdma_xprt *); 354 void (*ro_destroy)(struct rpcrdma_buffer *); 355 const char *ro_displayname; 356 }; 357 358 extern const struct rpcrdma_memreg_ops rpcrdma_fmr_memreg_ops; 359 extern const struct rpcrdma_memreg_ops rpcrdma_frwr_memreg_ops; 360 extern const struct rpcrdma_memreg_ops rpcrdma_physical_memreg_ops; 361 362 /* 363 * RPCRDMA transport -- encapsulates the structures above for 364 * integration with RPC. 365 * 366 * The contained structures are embedded, not pointers, 367 * for convenience. This structure need not be visible externally. 368 * 369 * It is allocated and initialized during mount, and released 370 * during unmount. 371 */ 372 struct rpcrdma_xprt { 373 struct rpc_xprt rx_xprt; 374 struct rpcrdma_ia rx_ia; 375 struct rpcrdma_ep rx_ep; 376 struct rpcrdma_buffer rx_buf; 377 struct rpcrdma_create_data_internal rx_data; 378 struct delayed_work rx_connect_worker; 379 struct rpcrdma_stats rx_stats; 380 }; 381 382 #define rpcx_to_rdmax(x) container_of(x, struct rpcrdma_xprt, rx_xprt) 383 #define rpcx_to_rdmad(x) (rpcx_to_rdmax(x)->rx_data) 384 385 /* Setting this to 0 ensures interoperability with early servers. 386 * Setting this to 1 enhances certain unaligned read/write performance. 387 * Default is 0, see sysctl entry and rpc_rdma.c rpcrdma_convert_iovs() */ 388 extern int xprt_rdma_pad_optimize; 389 390 /* 391 * Interface Adapter calls - xprtrdma/verbs.c 392 */ 393 int rpcrdma_ia_open(struct rpcrdma_xprt *, struct sockaddr *, int); 394 void rpcrdma_ia_close(struct rpcrdma_ia *); 395 396 /* 397 * Endpoint calls - xprtrdma/verbs.c 398 */ 399 int rpcrdma_ep_create(struct rpcrdma_ep *, struct rpcrdma_ia *, 400 struct rpcrdma_create_data_internal *); 401 void rpcrdma_ep_destroy(struct rpcrdma_ep *, struct rpcrdma_ia *); 402 int rpcrdma_ep_connect(struct rpcrdma_ep *, struct rpcrdma_ia *); 403 void rpcrdma_ep_disconnect(struct rpcrdma_ep *, struct rpcrdma_ia *); 404 405 int rpcrdma_ep_post(struct rpcrdma_ia *, struct rpcrdma_ep *, 406 struct rpcrdma_req *); 407 int rpcrdma_ep_post_recv(struct rpcrdma_ia *, struct rpcrdma_ep *, 408 struct rpcrdma_rep *); 409 410 /* 411 * Buffer calls - xprtrdma/verbs.c 412 */ 413 int rpcrdma_buffer_create(struct rpcrdma_xprt *); 414 void rpcrdma_buffer_destroy(struct rpcrdma_buffer *); 415 416 struct rpcrdma_req *rpcrdma_buffer_get(struct rpcrdma_buffer *); 417 void rpcrdma_buffer_put(struct rpcrdma_req *); 418 void rpcrdma_recv_buffer_get(struct rpcrdma_req *); 419 void rpcrdma_recv_buffer_put(struct rpcrdma_rep *); 420 421 struct rpcrdma_regbuf *rpcrdma_alloc_regbuf(struct rpcrdma_ia *, 422 size_t, gfp_t); 423 void rpcrdma_free_regbuf(struct rpcrdma_ia *, 424 struct rpcrdma_regbuf *); 425 426 unsigned int rpcrdma_max_segments(struct rpcrdma_xprt *); 427 428 /* 429 * Wrappers for chunk registration, shared by read/write chunk code. 430 */ 431 432 void rpcrdma_mapping_error(struct rpcrdma_mr_seg *); 433 434 static inline enum dma_data_direction 435 rpcrdma_data_dir(bool writing) 436 { 437 return writing ? DMA_FROM_DEVICE : DMA_TO_DEVICE; 438 } 439 440 static inline void 441 rpcrdma_map_one(struct ib_device *device, struct rpcrdma_mr_seg *seg, 442 enum dma_data_direction direction) 443 { 444 seg->mr_dir = direction; 445 seg->mr_dmalen = seg->mr_len; 446 447 if (seg->mr_page) 448 seg->mr_dma = ib_dma_map_page(device, 449 seg->mr_page, offset_in_page(seg->mr_offset), 450 seg->mr_dmalen, seg->mr_dir); 451 else 452 seg->mr_dma = ib_dma_map_single(device, 453 seg->mr_offset, 454 seg->mr_dmalen, seg->mr_dir); 455 456 if (ib_dma_mapping_error(device, seg->mr_dma)) 457 rpcrdma_mapping_error(seg); 458 } 459 460 static inline void 461 rpcrdma_unmap_one(struct ib_device *device, struct rpcrdma_mr_seg *seg) 462 { 463 if (seg->mr_page) 464 ib_dma_unmap_page(device, 465 seg->mr_dma, seg->mr_dmalen, seg->mr_dir); 466 else 467 ib_dma_unmap_single(device, 468 seg->mr_dma, seg->mr_dmalen, seg->mr_dir); 469 } 470 471 /* 472 * RPC/RDMA connection management calls - xprtrdma/rpc_rdma.c 473 */ 474 void rpcrdma_connect_worker(struct work_struct *); 475 void rpcrdma_conn_func(struct rpcrdma_ep *); 476 void rpcrdma_reply_handler(struct rpcrdma_rep *); 477 478 /* 479 * RPC/RDMA protocol calls - xprtrdma/rpc_rdma.c 480 */ 481 int rpcrdma_marshal_req(struct rpc_rqst *); 482 483 /* Temporary NFS request map cache. Created in svc_rdma.c */ 484 extern struct kmem_cache *svc_rdma_map_cachep; 485 /* WR context cache. Created in svc_rdma.c */ 486 extern struct kmem_cache *svc_rdma_ctxt_cachep; 487 /* Workqueue created in svc_rdma.c */ 488 extern struct workqueue_struct *svc_rdma_wq; 489 490 #if RPCSVC_MAXPAYLOAD < (RPCRDMA_MAX_DATA_SEGS << PAGE_SHIFT) 491 #define RPCSVC_MAXPAYLOAD_RDMA RPCSVC_MAXPAYLOAD 492 #else 493 #define RPCSVC_MAXPAYLOAD_RDMA (RPCRDMA_MAX_DATA_SEGS << PAGE_SHIFT) 494 #endif 495 496 #endif /* _LINUX_SUNRPC_XPRT_RDMA_H */ 497