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 ib_device *ri_device; 66 struct rdma_cm_id *ri_id; 67 struct ib_pd *ri_pd; 68 struct ib_mr *ri_bind_mem; 69 u32 ri_dma_lkey; 70 int ri_have_dma_lkey; 71 struct completion ri_done; 72 int ri_async_rc; 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 ib_device *rr_device; 177 struct rpcrdma_xprt *rr_rxprt; 178 struct list_head rr_list; 179 struct rpcrdma_regbuf *rr_rdmabuf; 180 }; 181 182 /* 183 * struct rpcrdma_mw - external memory region metadata 184 * 185 * An external memory region is any buffer or page that is registered 186 * on the fly (ie, not pre-registered). 187 * 188 * Each rpcrdma_buffer has a list of free MWs anchored in rb_mws. During 189 * call_allocate, rpcrdma_buffer_get() assigns one to each segment in 190 * an rpcrdma_req. Then rpcrdma_register_external() grabs these to keep 191 * track of registration metadata while each RPC is pending. 192 * rpcrdma_deregister_external() uses this metadata to unmap and 193 * release these resources when an RPC is complete. 194 */ 195 enum rpcrdma_frmr_state { 196 FRMR_IS_INVALID, /* ready to be used */ 197 FRMR_IS_VALID, /* in use */ 198 FRMR_IS_STALE, /* failed completion */ 199 }; 200 201 struct rpcrdma_frmr { 202 struct ib_fast_reg_page_list *fr_pgl; 203 struct ib_mr *fr_mr; 204 enum rpcrdma_frmr_state fr_state; 205 struct work_struct fr_work; 206 struct rpcrdma_xprt *fr_xprt; 207 }; 208 209 struct rpcrdma_fmr { 210 struct ib_fmr *fmr; 211 u64 *physaddrs; 212 }; 213 214 struct rpcrdma_mw { 215 union { 216 struct rpcrdma_fmr fmr; 217 struct rpcrdma_frmr frmr; 218 } r; 219 void (*mw_sendcompletion)(struct ib_wc *); 220 struct list_head mw_list; 221 struct list_head mw_all; 222 }; 223 224 /* 225 * struct rpcrdma_req -- structure central to the request/reply sequence. 226 * 227 * N of these are associated with a transport instance, and stored in 228 * struct rpcrdma_buffer. N is the max number of outstanding requests. 229 * 230 * It includes pre-registered buffer memory for send AND recv. 231 * The recv buffer, however, is not owned by this structure, and 232 * is "donated" to the hardware when a recv is posted. When a 233 * reply is handled, the recv buffer used is given back to the 234 * struct rpcrdma_req associated with the request. 235 * 236 * In addition to the basic memory, this structure includes an array 237 * of iovs for send operations. The reason is that the iovs passed to 238 * ib_post_{send,recv} must not be modified until the work request 239 * completes. 240 * 241 * NOTES: 242 * o RPCRDMA_MAX_SEGS is the max number of addressible chunk elements we 243 * marshal. The number needed varies depending on the iov lists that 244 * are passed to us, the memory registration mode we are in, and if 245 * physical addressing is used, the layout. 246 */ 247 248 struct rpcrdma_mr_seg { /* chunk descriptors */ 249 struct rpcrdma_mw *rl_mw; /* registered MR */ 250 u64 mr_base; /* registration result */ 251 u32 mr_rkey; /* registration result */ 252 u32 mr_len; /* length of chunk or segment */ 253 int mr_nsegs; /* number of segments in chunk or 0 */ 254 enum dma_data_direction mr_dir; /* segment mapping direction */ 255 dma_addr_t mr_dma; /* segment mapping address */ 256 size_t mr_dmalen; /* segment mapping length */ 257 struct page *mr_page; /* owning page, if any */ 258 char *mr_offset; /* kva if no page, else offset */ 259 }; 260 261 struct rpcrdma_req { 262 unsigned int rl_niovs; /* 0, 2 or 4 */ 263 unsigned int rl_nchunks; /* non-zero if chunks */ 264 unsigned int rl_connect_cookie; /* retry detection */ 265 struct rpcrdma_buffer *rl_buffer; /* home base for this structure */ 266 struct rpcrdma_rep *rl_reply;/* holder for reply buffer */ 267 struct ib_sge rl_send_iov[4]; /* for active requests */ 268 struct rpcrdma_regbuf *rl_rdmabuf; 269 struct rpcrdma_regbuf *rl_sendbuf; 270 struct rpcrdma_mr_seg rl_segments[RPCRDMA_MAX_SEGS]; 271 }; 272 273 static inline struct rpcrdma_req * 274 rpcr_to_rdmar(struct rpc_rqst *rqst) 275 { 276 void *buffer = rqst->rq_buffer; 277 struct rpcrdma_regbuf *rb; 278 279 rb = container_of(buffer, struct rpcrdma_regbuf, rg_base); 280 return rb->rg_owner; 281 } 282 283 /* 284 * struct rpcrdma_buffer -- holds list/queue of pre-registered memory for 285 * inline requests/replies, and client/server credits. 286 * 287 * One of these is associated with a transport instance 288 */ 289 struct rpcrdma_buffer { 290 spinlock_t rb_mwlock; /* protect rb_mws list */ 291 struct list_head rb_mws; 292 struct list_head rb_all; 293 char *rb_pool; 294 295 spinlock_t rb_lock; /* protect buf arrays */ 296 u32 rb_max_requests; 297 int rb_send_index; 298 int rb_recv_index; 299 struct rpcrdma_req **rb_send_bufs; 300 struct rpcrdma_rep **rb_recv_bufs; 301 }; 302 #define rdmab_to_ia(b) (&container_of((b), struct rpcrdma_xprt, rx_buf)->rx_ia) 303 304 /* 305 * Internal structure for transport instance creation. This 306 * exists primarily for modularity. 307 * 308 * This data should be set with mount options 309 */ 310 struct rpcrdma_create_data_internal { 311 struct sockaddr_storage addr; /* RDMA server address */ 312 unsigned int max_requests; /* max requests (slots) in flight */ 313 unsigned int rsize; /* mount rsize - max read hdr+data */ 314 unsigned int wsize; /* mount wsize - max write hdr+data */ 315 unsigned int inline_rsize; /* max non-rdma read data payload */ 316 unsigned int inline_wsize; /* max non-rdma write data payload */ 317 unsigned int padding; /* non-rdma write header padding */ 318 }; 319 320 #define RPCRDMA_INLINE_READ_THRESHOLD(rq) \ 321 (rpcx_to_rdmad(rq->rq_xprt).inline_rsize) 322 323 #define RPCRDMA_INLINE_WRITE_THRESHOLD(rq)\ 324 (rpcx_to_rdmad(rq->rq_xprt).inline_wsize) 325 326 #define RPCRDMA_INLINE_PAD_VALUE(rq)\ 327 rpcx_to_rdmad(rq->rq_xprt).padding 328 329 /* 330 * Statistics for RPCRDMA 331 */ 332 struct rpcrdma_stats { 333 unsigned long read_chunk_count; 334 unsigned long write_chunk_count; 335 unsigned long reply_chunk_count; 336 337 unsigned long long total_rdma_request; 338 unsigned long long total_rdma_reply; 339 340 unsigned long long pullup_copy_count; 341 unsigned long long fixup_copy_count; 342 unsigned long hardway_register_count; 343 unsigned long failed_marshal_count; 344 unsigned long bad_reply_count; 345 }; 346 347 /* 348 * Per-registration mode operations 349 */ 350 struct rpcrdma_xprt; 351 struct rpcrdma_memreg_ops { 352 int (*ro_map)(struct rpcrdma_xprt *, 353 struct rpcrdma_mr_seg *, int, bool); 354 int (*ro_unmap)(struct rpcrdma_xprt *, 355 struct rpcrdma_mr_seg *); 356 int (*ro_open)(struct rpcrdma_ia *, 357 struct rpcrdma_ep *, 358 struct rpcrdma_create_data_internal *); 359 size_t (*ro_maxpages)(struct rpcrdma_xprt *); 360 int (*ro_init)(struct rpcrdma_xprt *); 361 void (*ro_destroy)(struct rpcrdma_buffer *); 362 const char *ro_displayname; 363 }; 364 365 extern const struct rpcrdma_memreg_ops rpcrdma_fmr_memreg_ops; 366 extern const struct rpcrdma_memreg_ops rpcrdma_frwr_memreg_ops; 367 extern const struct rpcrdma_memreg_ops rpcrdma_physical_memreg_ops; 368 369 /* 370 * RPCRDMA transport -- encapsulates the structures above for 371 * integration with RPC. 372 * 373 * The contained structures are embedded, not pointers, 374 * for convenience. This structure need not be visible externally. 375 * 376 * It is allocated and initialized during mount, and released 377 * during unmount. 378 */ 379 struct rpcrdma_xprt { 380 struct rpc_xprt rx_xprt; 381 struct rpcrdma_ia rx_ia; 382 struct rpcrdma_ep rx_ep; 383 struct rpcrdma_buffer rx_buf; 384 struct rpcrdma_create_data_internal rx_data; 385 struct delayed_work rx_connect_worker; 386 struct rpcrdma_stats rx_stats; 387 }; 388 389 #define rpcx_to_rdmax(x) container_of(x, struct rpcrdma_xprt, rx_xprt) 390 #define rpcx_to_rdmad(x) (rpcx_to_rdmax(x)->rx_data) 391 392 /* Setting this to 0 ensures interoperability with early servers. 393 * Setting this to 1 enhances certain unaligned read/write performance. 394 * Default is 0, see sysctl entry and rpc_rdma.c rpcrdma_convert_iovs() */ 395 extern int xprt_rdma_pad_optimize; 396 397 /* 398 * Interface Adapter calls - xprtrdma/verbs.c 399 */ 400 int rpcrdma_ia_open(struct rpcrdma_xprt *, struct sockaddr *, int); 401 void rpcrdma_ia_close(struct rpcrdma_ia *); 402 403 /* 404 * Endpoint calls - xprtrdma/verbs.c 405 */ 406 int rpcrdma_ep_create(struct rpcrdma_ep *, struct rpcrdma_ia *, 407 struct rpcrdma_create_data_internal *); 408 void rpcrdma_ep_destroy(struct rpcrdma_ep *, struct rpcrdma_ia *); 409 int rpcrdma_ep_connect(struct rpcrdma_ep *, struct rpcrdma_ia *); 410 void rpcrdma_ep_disconnect(struct rpcrdma_ep *, struct rpcrdma_ia *); 411 412 int rpcrdma_ep_post(struct rpcrdma_ia *, struct rpcrdma_ep *, 413 struct rpcrdma_req *); 414 int rpcrdma_ep_post_recv(struct rpcrdma_ia *, struct rpcrdma_ep *, 415 struct rpcrdma_rep *); 416 417 /* 418 * Buffer calls - xprtrdma/verbs.c 419 */ 420 int rpcrdma_buffer_create(struct rpcrdma_xprt *); 421 void rpcrdma_buffer_destroy(struct rpcrdma_buffer *); 422 423 struct rpcrdma_mw *rpcrdma_get_mw(struct rpcrdma_xprt *); 424 void rpcrdma_put_mw(struct rpcrdma_xprt *, struct rpcrdma_mw *); 425 struct rpcrdma_req *rpcrdma_buffer_get(struct rpcrdma_buffer *); 426 void rpcrdma_buffer_put(struct rpcrdma_req *); 427 void rpcrdma_recv_buffer_get(struct rpcrdma_req *); 428 void rpcrdma_recv_buffer_put(struct rpcrdma_rep *); 429 430 struct rpcrdma_regbuf *rpcrdma_alloc_regbuf(struct rpcrdma_ia *, 431 size_t, gfp_t); 432 void rpcrdma_free_regbuf(struct rpcrdma_ia *, 433 struct rpcrdma_regbuf *); 434 435 unsigned int rpcrdma_max_segments(struct rpcrdma_xprt *); 436 437 int frwr_alloc_recovery_wq(void); 438 void frwr_destroy_recovery_wq(void); 439 440 /* 441 * Wrappers for chunk registration, shared by read/write chunk code. 442 */ 443 444 void rpcrdma_mapping_error(struct rpcrdma_mr_seg *); 445 446 static inline enum dma_data_direction 447 rpcrdma_data_dir(bool writing) 448 { 449 return writing ? DMA_FROM_DEVICE : DMA_TO_DEVICE; 450 } 451 452 static inline void 453 rpcrdma_map_one(struct ib_device *device, struct rpcrdma_mr_seg *seg, 454 enum dma_data_direction direction) 455 { 456 seg->mr_dir = direction; 457 seg->mr_dmalen = seg->mr_len; 458 459 if (seg->mr_page) 460 seg->mr_dma = ib_dma_map_page(device, 461 seg->mr_page, offset_in_page(seg->mr_offset), 462 seg->mr_dmalen, seg->mr_dir); 463 else 464 seg->mr_dma = ib_dma_map_single(device, 465 seg->mr_offset, 466 seg->mr_dmalen, seg->mr_dir); 467 468 if (ib_dma_mapping_error(device, seg->mr_dma)) 469 rpcrdma_mapping_error(seg); 470 } 471 472 static inline void 473 rpcrdma_unmap_one(struct ib_device *device, struct rpcrdma_mr_seg *seg) 474 { 475 if (seg->mr_page) 476 ib_dma_unmap_page(device, 477 seg->mr_dma, seg->mr_dmalen, seg->mr_dir); 478 else 479 ib_dma_unmap_single(device, 480 seg->mr_dma, seg->mr_dmalen, seg->mr_dir); 481 } 482 483 /* 484 * RPC/RDMA connection management calls - xprtrdma/rpc_rdma.c 485 */ 486 void rpcrdma_connect_worker(struct work_struct *); 487 void rpcrdma_conn_func(struct rpcrdma_ep *); 488 void rpcrdma_reply_handler(struct rpcrdma_rep *); 489 490 /* 491 * RPC/RDMA protocol calls - xprtrdma/rpc_rdma.c 492 */ 493 int rpcrdma_marshal_req(struct rpc_rqst *); 494 495 /* RPC/RDMA module init - xprtrdma/transport.c 496 */ 497 int xprt_rdma_init(void); 498 void xprt_rdma_cleanup(void); 499 500 /* Temporary NFS request map cache. Created in svc_rdma.c */ 501 extern struct kmem_cache *svc_rdma_map_cachep; 502 /* WR context cache. Created in svc_rdma.c */ 503 extern struct kmem_cache *svc_rdma_ctxt_cachep; 504 /* Workqueue created in svc_rdma.c */ 505 extern struct workqueue_struct *svc_rdma_wq; 506 507 #endif /* _LINUX_SUNRPC_XPRT_RDMA_H */ 508