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 55 #define RDMA_RESOLVE_TIMEOUT (5000) /* 5 seconds */ 56 #define RDMA_CONNECT_RETRY_MAX (2) /* retries if no listener backlog */ 57 58 #define RPCRDMA_BIND_TO (60U * HZ) 59 #define RPCRDMA_INIT_REEST_TO (5U * HZ) 60 #define RPCRDMA_MAX_REEST_TO (30U * HZ) 61 #define RPCRDMA_IDLE_DISC_TO (5U * 60 * HZ) 62 63 /* 64 * Interface Adapter -- one per transport instance 65 */ 66 struct rpcrdma_ia { 67 const struct rpcrdma_memreg_ops *ri_ops; 68 rwlock_t ri_qplock; 69 struct ib_device *ri_device; 70 struct rdma_cm_id *ri_id; 71 struct ib_pd *ri_pd; 72 struct ib_mr *ri_dma_mr; 73 struct completion ri_done; 74 int ri_async_rc; 75 unsigned int ri_max_frmr_depth; 76 struct ib_qp_attr ri_qp_attr; 77 struct ib_qp_init_attr ri_qp_init_attr; 78 }; 79 80 /* 81 * RDMA Endpoint -- one per transport instance 82 */ 83 84 struct rpcrdma_ep { 85 atomic_t rep_cqcount; 86 int rep_cqinit; 87 int rep_connected; 88 struct ib_qp_init_attr rep_attr; 89 wait_queue_head_t rep_connect_wait; 90 struct rdma_conn_param rep_remote_cma; 91 struct sockaddr_storage rep_remote_addr; 92 struct delayed_work rep_connect_worker; 93 }; 94 95 #define INIT_CQCOUNT(ep) atomic_set(&(ep)->rep_cqcount, (ep)->rep_cqinit) 96 #define DECR_CQCOUNT(ep) atomic_sub_return(1, &(ep)->rep_cqcount) 97 98 /* Pre-allocate extra Work Requests for handling backward receives 99 * and sends. This is a fixed value because the Work Queues are 100 * allocated when the forward channel is set up. 101 */ 102 #if defined(CONFIG_SUNRPC_BACKCHANNEL) 103 #define RPCRDMA_BACKWARD_WRS (8) 104 #else 105 #define RPCRDMA_BACKWARD_WRS (0) 106 #endif 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_sge rg_iov; 118 __be32 rg_base[0] __attribute__ ((aligned(256))); 119 }; 120 121 static inline u64 122 rdmab_addr(struct rpcrdma_regbuf *rb) 123 { 124 return rb->rg_iov.addr; 125 } 126 127 static inline u32 128 rdmab_length(struct rpcrdma_regbuf *rb) 129 { 130 return rb->rg_iov.length; 131 } 132 133 static inline u32 134 rdmab_lkey(struct rpcrdma_regbuf *rb) 135 { 136 return rb->rg_iov.lkey; 137 } 138 139 static inline struct rpcrdma_msg * 140 rdmab_to_msg(struct rpcrdma_regbuf *rb) 141 { 142 return (struct rpcrdma_msg *)rb->rg_base; 143 } 144 145 #define RPCRDMA_DEF_GFP (GFP_NOIO | __GFP_NOWARN) 146 147 /* 148 * struct rpcrdma_rep -- this structure encapsulates state required to recv 149 * and complete a reply, asychronously. It needs several pieces of 150 * state: 151 * o recv buffer (posted to provider) 152 * o ib_sge (also donated to provider) 153 * o status of reply (length, success or not) 154 * o bookkeeping state to get run by tasklet (list, etc) 155 * 156 * These are allocated during initialization, per-transport instance; 157 * however, the tasklet execution list itself is global, as it should 158 * always be pretty short. 159 * 160 * N of these are associated with a transport instance, and stored in 161 * struct rpcrdma_buffer. N is the max number of outstanding requests. 162 */ 163 164 #define RPCRDMA_MAX_DATA_SEGS ((1 * 1024 * 1024) / PAGE_SIZE) 165 #define RPCRDMA_MAX_SEGS (RPCRDMA_MAX_DATA_SEGS + 2) /* head+tail = 2 */ 166 167 struct rpcrdma_buffer; 168 169 struct rpcrdma_rep { 170 struct ib_cqe rr_cqe; 171 unsigned int rr_len; 172 struct ib_device *rr_device; 173 struct rpcrdma_xprt *rr_rxprt; 174 struct work_struct rr_work; 175 struct list_head rr_list; 176 struct rpcrdma_regbuf *rr_rdmabuf; 177 }; 178 179 #define RPCRDMA_BAD_LEN (~0U) 180 181 /* 182 * struct rpcrdma_mw - external memory region metadata 183 * 184 * An external memory region is any buffer or page that is registered 185 * on the fly (ie, not pre-registered). 186 * 187 * Each rpcrdma_buffer has a list of free MWs anchored in rb_mws. During 188 * call_allocate, rpcrdma_buffer_get() assigns one to each segment in 189 * an rpcrdma_req. Then rpcrdma_register_external() grabs these to keep 190 * track of registration metadata while each RPC is pending. 191 * rpcrdma_deregister_external() uses this metadata to unmap and 192 * release these resources when an RPC is complete. 193 */ 194 enum rpcrdma_frmr_state { 195 FRMR_IS_INVALID, /* ready to be used */ 196 FRMR_IS_VALID, /* in use */ 197 FRMR_IS_STALE, /* failed completion */ 198 }; 199 200 struct rpcrdma_frmr { 201 struct scatterlist *sg; 202 int sg_nents; 203 struct ib_mr *fr_mr; 204 struct ib_cqe fr_cqe; 205 enum rpcrdma_frmr_state fr_state; 206 struct completion fr_linv_done; 207 struct work_struct fr_work; 208 struct rpcrdma_xprt *fr_xprt; 209 union { 210 struct ib_reg_wr fr_regwr; 211 struct ib_send_wr fr_invwr; 212 }; 213 }; 214 215 struct rpcrdma_fmr { 216 struct ib_fmr *fmr; 217 u64 *physaddrs; 218 }; 219 220 struct rpcrdma_mw { 221 union { 222 struct rpcrdma_fmr fmr; 223 struct rpcrdma_frmr frmr; 224 }; 225 struct list_head mw_list; 226 struct list_head mw_all; 227 }; 228 229 /* 230 * struct rpcrdma_req -- structure central to the request/reply sequence. 231 * 232 * N of these are associated with a transport instance, and stored in 233 * struct rpcrdma_buffer. N is the max number of outstanding requests. 234 * 235 * It includes pre-registered buffer memory for send AND recv. 236 * The recv buffer, however, is not owned by this structure, and 237 * is "donated" to the hardware when a recv is posted. When a 238 * reply is handled, the recv buffer used is given back to the 239 * struct rpcrdma_req associated with the request. 240 * 241 * In addition to the basic memory, this structure includes an array 242 * of iovs for send operations. The reason is that the iovs passed to 243 * ib_post_{send,recv} must not be modified until the work request 244 * completes. 245 * 246 * NOTES: 247 * o RPCRDMA_MAX_SEGS is the max number of addressible chunk elements we 248 * marshal. The number needed varies depending on the iov lists that 249 * are passed to us, the memory registration mode we are in, and if 250 * physical addressing is used, the layout. 251 */ 252 253 struct rpcrdma_mr_seg { /* chunk descriptors */ 254 struct rpcrdma_mw *rl_mw; /* registered MR */ 255 u64 mr_base; /* registration result */ 256 u32 mr_rkey; /* registration result */ 257 u32 mr_len; /* length of chunk or segment */ 258 int mr_nsegs; /* number of segments in chunk or 0 */ 259 enum dma_data_direction mr_dir; /* segment mapping direction */ 260 dma_addr_t mr_dma; /* segment mapping address */ 261 size_t mr_dmalen; /* segment mapping length */ 262 struct page *mr_page; /* owning page, if any */ 263 char *mr_offset; /* kva if no page, else offset */ 264 }; 265 266 #define RPCRDMA_MAX_IOVS (2) 267 268 struct rpcrdma_req { 269 struct list_head rl_free; 270 unsigned int rl_niovs; 271 unsigned int rl_nchunks; 272 unsigned int rl_connect_cookie; 273 struct rpcrdma_buffer *rl_buffer; 274 struct rpcrdma_rep *rl_reply;/* holder for reply buffer */ 275 struct ib_sge rl_send_iov[RPCRDMA_MAX_IOVS]; 276 struct rpcrdma_regbuf *rl_rdmabuf; 277 struct rpcrdma_regbuf *rl_sendbuf; 278 struct rpcrdma_mr_seg rl_segments[RPCRDMA_MAX_SEGS]; 279 280 struct ib_cqe rl_cqe; 281 struct list_head rl_all; 282 bool rl_backchannel; 283 }; 284 285 static inline struct rpcrdma_req * 286 rpcr_to_rdmar(struct rpc_rqst *rqst) 287 { 288 void *buffer = rqst->rq_buffer; 289 struct rpcrdma_regbuf *rb; 290 291 rb = container_of(buffer, struct rpcrdma_regbuf, rg_base); 292 return rb->rg_owner; 293 } 294 295 /* 296 * struct rpcrdma_buffer -- holds list/queue of pre-registered memory for 297 * inline requests/replies, and client/server credits. 298 * 299 * One of these is associated with a transport instance 300 */ 301 struct rpcrdma_buffer { 302 spinlock_t rb_mwlock; /* protect rb_mws list */ 303 struct list_head rb_mws; 304 struct list_head rb_all; 305 char *rb_pool; 306 307 spinlock_t rb_lock; /* protect buf lists */ 308 struct list_head rb_send_bufs; 309 struct list_head rb_recv_bufs; 310 u32 rb_max_requests; 311 atomic_t rb_credits; /* most recent credit grant */ 312 313 u32 rb_bc_srv_max_requests; 314 spinlock_t rb_reqslock; /* protect rb_allreqs */ 315 struct list_head rb_allreqs; 316 317 u32 rb_bc_max_requests; 318 }; 319 #define rdmab_to_ia(b) (&container_of((b), struct rpcrdma_xprt, rx_buf)->rx_ia) 320 321 /* 322 * Internal structure for transport instance creation. This 323 * exists primarily for modularity. 324 * 325 * This data should be set with mount options 326 */ 327 struct rpcrdma_create_data_internal { 328 struct sockaddr_storage addr; /* RDMA server address */ 329 unsigned int max_requests; /* max requests (slots) in flight */ 330 unsigned int rsize; /* mount rsize - max read hdr+data */ 331 unsigned int wsize; /* mount wsize - max write hdr+data */ 332 unsigned int inline_rsize; /* max non-rdma read data payload */ 333 unsigned int inline_wsize; /* max non-rdma write data payload */ 334 unsigned int padding; /* non-rdma write header padding */ 335 }; 336 337 #define RPCRDMA_INLINE_READ_THRESHOLD(rq) \ 338 (rpcx_to_rdmad(rq->rq_xprt).inline_rsize) 339 340 #define RPCRDMA_INLINE_WRITE_THRESHOLD(rq)\ 341 (rpcx_to_rdmad(rq->rq_xprt).inline_wsize) 342 343 #define RPCRDMA_INLINE_PAD_VALUE(rq)\ 344 rpcx_to_rdmad(rq->rq_xprt).padding 345 346 /* 347 * Statistics for RPCRDMA 348 */ 349 struct rpcrdma_stats { 350 unsigned long read_chunk_count; 351 unsigned long write_chunk_count; 352 unsigned long reply_chunk_count; 353 354 unsigned long long total_rdma_request; 355 unsigned long long total_rdma_reply; 356 357 unsigned long long pullup_copy_count; 358 unsigned long long fixup_copy_count; 359 unsigned long hardway_register_count; 360 unsigned long failed_marshal_count; 361 unsigned long bad_reply_count; 362 unsigned long nomsg_call_count; 363 unsigned long bcall_count; 364 }; 365 366 /* 367 * Per-registration mode operations 368 */ 369 struct rpcrdma_xprt; 370 struct rpcrdma_memreg_ops { 371 int (*ro_map)(struct rpcrdma_xprt *, 372 struct rpcrdma_mr_seg *, int, bool); 373 void (*ro_unmap_sync)(struct rpcrdma_xprt *, 374 struct rpcrdma_req *); 375 int (*ro_unmap)(struct rpcrdma_xprt *, 376 struct rpcrdma_mr_seg *); 377 int (*ro_open)(struct rpcrdma_ia *, 378 struct rpcrdma_ep *, 379 struct rpcrdma_create_data_internal *); 380 size_t (*ro_maxpages)(struct rpcrdma_xprt *); 381 int (*ro_init)(struct rpcrdma_xprt *); 382 void (*ro_destroy)(struct rpcrdma_buffer *); 383 const char *ro_displayname; 384 }; 385 386 extern const struct rpcrdma_memreg_ops rpcrdma_fmr_memreg_ops; 387 extern const struct rpcrdma_memreg_ops rpcrdma_frwr_memreg_ops; 388 extern const struct rpcrdma_memreg_ops rpcrdma_physical_memreg_ops; 389 390 /* 391 * RPCRDMA transport -- encapsulates the structures above for 392 * integration with RPC. 393 * 394 * The contained structures are embedded, not pointers, 395 * for convenience. This structure need not be visible externally. 396 * 397 * It is allocated and initialized during mount, and released 398 * during unmount. 399 */ 400 struct rpcrdma_xprt { 401 struct rpc_xprt rx_xprt; 402 struct rpcrdma_ia rx_ia; 403 struct rpcrdma_ep rx_ep; 404 struct rpcrdma_buffer rx_buf; 405 struct rpcrdma_create_data_internal rx_data; 406 struct delayed_work rx_connect_worker; 407 struct rpcrdma_stats rx_stats; 408 }; 409 410 #define rpcx_to_rdmax(x) container_of(x, struct rpcrdma_xprt, rx_xprt) 411 #define rpcx_to_rdmad(x) (rpcx_to_rdmax(x)->rx_data) 412 413 /* Setting this to 0 ensures interoperability with early servers. 414 * Setting this to 1 enhances certain unaligned read/write performance. 415 * Default is 0, see sysctl entry and rpc_rdma.c rpcrdma_convert_iovs() */ 416 extern int xprt_rdma_pad_optimize; 417 418 /* 419 * Interface Adapter calls - xprtrdma/verbs.c 420 */ 421 int rpcrdma_ia_open(struct rpcrdma_xprt *, struct sockaddr *, int); 422 void rpcrdma_ia_close(struct rpcrdma_ia *); 423 424 /* 425 * Endpoint calls - xprtrdma/verbs.c 426 */ 427 int rpcrdma_ep_create(struct rpcrdma_ep *, struct rpcrdma_ia *, 428 struct rpcrdma_create_data_internal *); 429 void rpcrdma_ep_destroy(struct rpcrdma_ep *, struct rpcrdma_ia *); 430 int rpcrdma_ep_connect(struct rpcrdma_ep *, struct rpcrdma_ia *); 431 void rpcrdma_ep_disconnect(struct rpcrdma_ep *, struct rpcrdma_ia *); 432 433 int rpcrdma_ep_post(struct rpcrdma_ia *, struct rpcrdma_ep *, 434 struct rpcrdma_req *); 435 int rpcrdma_ep_post_recv(struct rpcrdma_ia *, struct rpcrdma_ep *, 436 struct rpcrdma_rep *); 437 438 /* 439 * Buffer calls - xprtrdma/verbs.c 440 */ 441 struct rpcrdma_req *rpcrdma_create_req(struct rpcrdma_xprt *); 442 struct rpcrdma_rep *rpcrdma_create_rep(struct rpcrdma_xprt *); 443 void rpcrdma_destroy_req(struct rpcrdma_ia *, struct rpcrdma_req *); 444 int rpcrdma_buffer_create(struct rpcrdma_xprt *); 445 void rpcrdma_buffer_destroy(struct rpcrdma_buffer *); 446 447 struct rpcrdma_mw *rpcrdma_get_mw(struct rpcrdma_xprt *); 448 void rpcrdma_put_mw(struct rpcrdma_xprt *, struct rpcrdma_mw *); 449 struct rpcrdma_req *rpcrdma_buffer_get(struct rpcrdma_buffer *); 450 void rpcrdma_buffer_put(struct rpcrdma_req *); 451 void rpcrdma_recv_buffer_get(struct rpcrdma_req *); 452 void rpcrdma_recv_buffer_put(struct rpcrdma_rep *); 453 454 struct rpcrdma_regbuf *rpcrdma_alloc_regbuf(struct rpcrdma_ia *, 455 size_t, gfp_t); 456 void rpcrdma_free_regbuf(struct rpcrdma_ia *, 457 struct rpcrdma_regbuf *); 458 459 unsigned int rpcrdma_max_segments(struct rpcrdma_xprt *); 460 int rpcrdma_ep_post_extra_recv(struct rpcrdma_xprt *, unsigned int); 461 462 int frwr_alloc_recovery_wq(void); 463 void frwr_destroy_recovery_wq(void); 464 465 int rpcrdma_alloc_wq(void); 466 void rpcrdma_destroy_wq(void); 467 468 /* 469 * Wrappers for chunk registration, shared by read/write chunk code. 470 */ 471 472 void rpcrdma_mapping_error(struct rpcrdma_mr_seg *); 473 474 static inline enum dma_data_direction 475 rpcrdma_data_dir(bool writing) 476 { 477 return writing ? DMA_FROM_DEVICE : DMA_TO_DEVICE; 478 } 479 480 static inline void 481 rpcrdma_map_one(struct ib_device *device, struct rpcrdma_mr_seg *seg, 482 enum dma_data_direction direction) 483 { 484 seg->mr_dir = direction; 485 seg->mr_dmalen = seg->mr_len; 486 487 if (seg->mr_page) 488 seg->mr_dma = ib_dma_map_page(device, 489 seg->mr_page, offset_in_page(seg->mr_offset), 490 seg->mr_dmalen, seg->mr_dir); 491 else 492 seg->mr_dma = ib_dma_map_single(device, 493 seg->mr_offset, 494 seg->mr_dmalen, seg->mr_dir); 495 496 if (ib_dma_mapping_error(device, seg->mr_dma)) 497 rpcrdma_mapping_error(seg); 498 } 499 500 static inline void 501 rpcrdma_unmap_one(struct ib_device *device, struct rpcrdma_mr_seg *seg) 502 { 503 if (seg->mr_page) 504 ib_dma_unmap_page(device, 505 seg->mr_dma, seg->mr_dmalen, seg->mr_dir); 506 else 507 ib_dma_unmap_single(device, 508 seg->mr_dma, seg->mr_dmalen, seg->mr_dir); 509 } 510 511 /* 512 * RPC/RDMA connection management calls - xprtrdma/rpc_rdma.c 513 */ 514 void rpcrdma_connect_worker(struct work_struct *); 515 void rpcrdma_conn_func(struct rpcrdma_ep *); 516 void rpcrdma_reply_handler(struct rpcrdma_rep *); 517 518 /* 519 * RPC/RDMA protocol calls - xprtrdma/rpc_rdma.c 520 */ 521 int rpcrdma_marshal_req(struct rpc_rqst *); 522 523 /* RPC/RDMA module init - xprtrdma/transport.c 524 */ 525 extern unsigned int xprt_rdma_max_inline_read; 526 void xprt_rdma_format_addresses(struct rpc_xprt *xprt, struct sockaddr *sap); 527 void xprt_rdma_free_addresses(struct rpc_xprt *xprt); 528 void xprt_rdma_print_stats(struct rpc_xprt *xprt, struct seq_file *seq); 529 int xprt_rdma_init(void); 530 void xprt_rdma_cleanup(void); 531 532 /* Backchannel calls - xprtrdma/backchannel.c 533 */ 534 #if defined(CONFIG_SUNRPC_BACKCHANNEL) 535 int xprt_rdma_bc_setup(struct rpc_xprt *, unsigned int); 536 int xprt_rdma_bc_up(struct svc_serv *, struct net *); 537 int rpcrdma_bc_post_recv(struct rpcrdma_xprt *, unsigned int); 538 void rpcrdma_bc_receive_call(struct rpcrdma_xprt *, struct rpcrdma_rep *); 539 int rpcrdma_bc_marshal_reply(struct rpc_rqst *); 540 void xprt_rdma_bc_free_rqst(struct rpc_rqst *); 541 void xprt_rdma_bc_destroy(struct rpc_xprt *, unsigned int); 542 #endif /* CONFIG_SUNRPC_BACKCHANNEL */ 543 544 extern struct xprt_class xprt_rdma_bc; 545 546 #endif /* _LINUX_SUNRPC_XPRT_RDMA_H */ 547