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 /* 59 * Interface Adapter -- one per transport instance 60 */ 61 struct rpcrdma_ia { 62 const struct rpcrdma_memreg_ops *ri_ops; 63 rwlock_t ri_qplock; 64 struct ib_device *ri_device; 65 struct rdma_cm_id *ri_id; 66 struct ib_pd *ri_pd; 67 struct ib_mr *ri_dma_mr; 68 u32 ri_dma_lkey; 69 struct completion ri_done; 70 int ri_async_rc; 71 unsigned int ri_max_frmr_depth; 72 struct ib_device_attr ri_devattr; 73 struct ib_qp_attr ri_qp_attr; 74 struct ib_qp_init_attr ri_qp_init_attr; 75 }; 76 77 /* 78 * RDMA Endpoint -- one per transport instance 79 */ 80 81 #define RPCRDMA_WC_BUDGET (128) 82 #define RPCRDMA_POLLSIZE (16) 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 struct ib_wc rep_send_wcs[RPCRDMA_POLLSIZE]; 94 struct ib_wc rep_recv_wcs[RPCRDMA_POLLSIZE]; 95 }; 96 97 /* 98 * Force a signaled SEND Work Request every so often, 99 * in case the provider needs to do some housekeeping. 100 */ 101 #define RPCRDMA_MAX_UNSIGNALED_SENDS (32) 102 103 #define INIT_CQCOUNT(ep) atomic_set(&(ep)->rep_cqcount, (ep)->rep_cqinit) 104 #define DECR_CQCOUNT(ep) atomic_sub_return(1, &(ep)->rep_cqcount) 105 106 /* Force completion handler to ignore the signal 107 */ 108 #define RPCRDMA_IGNORE_COMPLETION (0ULL) 109 110 /* Registered buffer -- registered kmalloc'd memory for RDMA SEND/RECV 111 * 112 * The below structure appears at the front of a large region of kmalloc'd 113 * memory, which always starts on a good alignment boundary. 114 */ 115 116 struct rpcrdma_regbuf { 117 size_t rg_size; 118 struct rpcrdma_req *rg_owner; 119 struct ib_sge rg_iov; 120 __be32 rg_base[0] __attribute__ ((aligned(256))); 121 }; 122 123 static inline u64 124 rdmab_addr(struct rpcrdma_regbuf *rb) 125 { 126 return rb->rg_iov.addr; 127 } 128 129 static inline u32 130 rdmab_length(struct rpcrdma_regbuf *rb) 131 { 132 return rb->rg_iov.length; 133 } 134 135 static inline u32 136 rdmab_lkey(struct rpcrdma_regbuf *rb) 137 { 138 return rb->rg_iov.lkey; 139 } 140 141 static inline struct rpcrdma_msg * 142 rdmab_to_msg(struct rpcrdma_regbuf *rb) 143 { 144 return (struct rpcrdma_msg *)rb->rg_base; 145 } 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 unsigned int rr_len; 171 struct ib_device *rr_device; 172 struct rpcrdma_xprt *rr_rxprt; 173 struct list_head rr_list; 174 struct rpcrdma_regbuf *rr_rdmabuf; 175 }; 176 177 /* 178 * struct rpcrdma_mw - external memory region metadata 179 * 180 * An external memory region is any buffer or page that is registered 181 * on the fly (ie, not pre-registered). 182 * 183 * Each rpcrdma_buffer has a list of free MWs anchored in rb_mws. During 184 * call_allocate, rpcrdma_buffer_get() assigns one to each segment in 185 * an rpcrdma_req. Then rpcrdma_register_external() grabs these to keep 186 * track of registration metadata while each RPC is pending. 187 * rpcrdma_deregister_external() uses this metadata to unmap and 188 * release these resources when an RPC is complete. 189 */ 190 enum rpcrdma_frmr_state { 191 FRMR_IS_INVALID, /* ready to be used */ 192 FRMR_IS_VALID, /* in use */ 193 FRMR_IS_STALE, /* failed completion */ 194 }; 195 196 struct rpcrdma_frmr { 197 struct ib_fast_reg_page_list *fr_pgl; 198 struct ib_mr *fr_mr; 199 enum rpcrdma_frmr_state fr_state; 200 struct work_struct fr_work; 201 struct rpcrdma_xprt *fr_xprt; 202 }; 203 204 struct rpcrdma_fmr { 205 struct ib_fmr *fmr; 206 u64 *physaddrs; 207 }; 208 209 struct rpcrdma_mw { 210 union { 211 struct rpcrdma_fmr fmr; 212 struct rpcrdma_frmr frmr; 213 } r; 214 void (*mw_sendcompletion)(struct ib_wc *); 215 struct list_head mw_list; 216 struct list_head mw_all; 217 }; 218 219 /* 220 * struct rpcrdma_req -- structure central to the request/reply sequence. 221 * 222 * N of these are associated with a transport instance, and stored in 223 * struct rpcrdma_buffer. N is the max number of outstanding requests. 224 * 225 * It includes pre-registered buffer memory for send AND recv. 226 * The recv buffer, however, is not owned by this structure, and 227 * is "donated" to the hardware when a recv is posted. When a 228 * reply is handled, the recv buffer used is given back to the 229 * struct rpcrdma_req associated with the request. 230 * 231 * In addition to the basic memory, this structure includes an array 232 * of iovs for send operations. The reason is that the iovs passed to 233 * ib_post_{send,recv} must not be modified until the work request 234 * completes. 235 * 236 * NOTES: 237 * o RPCRDMA_MAX_SEGS is the max number of addressible chunk elements we 238 * marshal. The number needed varies depending on the iov lists that 239 * are passed to us, the memory registration mode we are in, and if 240 * physical addressing is used, the layout. 241 */ 242 243 struct rpcrdma_mr_seg { /* chunk descriptors */ 244 struct rpcrdma_mw *rl_mw; /* registered MR */ 245 u64 mr_base; /* registration result */ 246 u32 mr_rkey; /* registration result */ 247 u32 mr_len; /* length of chunk or segment */ 248 int mr_nsegs; /* number of segments in chunk or 0 */ 249 enum dma_data_direction mr_dir; /* segment mapping direction */ 250 dma_addr_t mr_dma; /* segment mapping address */ 251 size_t mr_dmalen; /* segment mapping length */ 252 struct page *mr_page; /* owning page, if any */ 253 char *mr_offset; /* kva if no page, else offset */ 254 }; 255 256 #define RPCRDMA_MAX_IOVS (2) 257 258 struct rpcrdma_req { 259 unsigned int rl_niovs; 260 unsigned int rl_nchunks; 261 unsigned int rl_connect_cookie; 262 struct rpcrdma_buffer *rl_buffer; 263 struct rpcrdma_rep *rl_reply;/* holder for reply buffer */ 264 struct ib_sge rl_send_iov[RPCRDMA_MAX_IOVS]; 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_mwlock; /* protect rb_mws list */ 288 struct list_head rb_mws; 289 struct list_head rb_all; 290 char *rb_pool; 291 292 spinlock_t rb_lock; /* protect buf arrays */ 293 u32 rb_max_requests; 294 int rb_send_index; 295 int rb_recv_index; 296 struct rpcrdma_req **rb_send_bufs; 297 struct rpcrdma_rep **rb_recv_bufs; 298 }; 299 #define rdmab_to_ia(b) (&container_of((b), struct rpcrdma_xprt, rx_buf)->rx_ia) 300 301 /* 302 * Internal structure for transport instance creation. This 303 * exists primarily for modularity. 304 * 305 * This data should be set with mount options 306 */ 307 struct rpcrdma_create_data_internal { 308 struct sockaddr_storage addr; /* RDMA server address */ 309 unsigned int max_requests; /* max requests (slots) in flight */ 310 unsigned int rsize; /* mount rsize - max read hdr+data */ 311 unsigned int wsize; /* mount wsize - max write hdr+data */ 312 unsigned int inline_rsize; /* max non-rdma read data payload */ 313 unsigned int inline_wsize; /* max non-rdma write data payload */ 314 unsigned int padding; /* non-rdma write header padding */ 315 }; 316 317 #define RPCRDMA_INLINE_READ_THRESHOLD(rq) \ 318 (rpcx_to_rdmad(rq->rq_xprt).inline_rsize) 319 320 #define RPCRDMA_INLINE_WRITE_THRESHOLD(rq)\ 321 (rpcx_to_rdmad(rq->rq_xprt).inline_wsize) 322 323 #define RPCRDMA_INLINE_PAD_VALUE(rq)\ 324 rpcx_to_rdmad(rq->rq_xprt).padding 325 326 /* 327 * Statistics for RPCRDMA 328 */ 329 struct rpcrdma_stats { 330 unsigned long read_chunk_count; 331 unsigned long write_chunk_count; 332 unsigned long reply_chunk_count; 333 334 unsigned long long total_rdma_request; 335 unsigned long long total_rdma_reply; 336 337 unsigned long long pullup_copy_count; 338 unsigned long long fixup_copy_count; 339 unsigned long hardway_register_count; 340 unsigned long failed_marshal_count; 341 unsigned long bad_reply_count; 342 unsigned long nomsg_call_count; 343 }; 344 345 /* 346 * Per-registration mode operations 347 */ 348 struct rpcrdma_xprt; 349 struct rpcrdma_memreg_ops { 350 int (*ro_map)(struct rpcrdma_xprt *, 351 struct rpcrdma_mr_seg *, int, bool); 352 int (*ro_unmap)(struct rpcrdma_xprt *, 353 struct rpcrdma_mr_seg *); 354 int (*ro_open)(struct rpcrdma_ia *, 355 struct rpcrdma_ep *, 356 struct rpcrdma_create_data_internal *); 357 size_t (*ro_maxpages)(struct rpcrdma_xprt *); 358 int (*ro_init)(struct rpcrdma_xprt *); 359 void (*ro_destroy)(struct rpcrdma_buffer *); 360 const char *ro_displayname; 361 }; 362 363 extern const struct rpcrdma_memreg_ops rpcrdma_fmr_memreg_ops; 364 extern const struct rpcrdma_memreg_ops rpcrdma_frwr_memreg_ops; 365 extern const struct rpcrdma_memreg_ops rpcrdma_physical_memreg_ops; 366 367 /* 368 * RPCRDMA transport -- encapsulates the structures above for 369 * integration with RPC. 370 * 371 * The contained structures are embedded, not pointers, 372 * for convenience. This structure need not be visible externally. 373 * 374 * It is allocated and initialized during mount, and released 375 * during unmount. 376 */ 377 struct rpcrdma_xprt { 378 struct rpc_xprt rx_xprt; 379 struct rpcrdma_ia rx_ia; 380 struct rpcrdma_ep rx_ep; 381 struct rpcrdma_buffer rx_buf; 382 struct rpcrdma_create_data_internal rx_data; 383 struct delayed_work rx_connect_worker; 384 struct rpcrdma_stats rx_stats; 385 }; 386 387 #define rpcx_to_rdmax(x) container_of(x, struct rpcrdma_xprt, rx_xprt) 388 #define rpcx_to_rdmad(x) (rpcx_to_rdmax(x)->rx_data) 389 390 /* Setting this to 0 ensures interoperability with early servers. 391 * Setting this to 1 enhances certain unaligned read/write performance. 392 * Default is 0, see sysctl entry and rpc_rdma.c rpcrdma_convert_iovs() */ 393 extern int xprt_rdma_pad_optimize; 394 395 /* 396 * Interface Adapter calls - xprtrdma/verbs.c 397 */ 398 int rpcrdma_ia_open(struct rpcrdma_xprt *, struct sockaddr *, int); 399 void rpcrdma_ia_close(struct rpcrdma_ia *); 400 401 /* 402 * Endpoint calls - xprtrdma/verbs.c 403 */ 404 int rpcrdma_ep_create(struct rpcrdma_ep *, struct rpcrdma_ia *, 405 struct rpcrdma_create_data_internal *); 406 void rpcrdma_ep_destroy(struct rpcrdma_ep *, struct rpcrdma_ia *); 407 int rpcrdma_ep_connect(struct rpcrdma_ep *, struct rpcrdma_ia *); 408 void rpcrdma_ep_disconnect(struct rpcrdma_ep *, struct rpcrdma_ia *); 409 410 int rpcrdma_ep_post(struct rpcrdma_ia *, struct rpcrdma_ep *, 411 struct rpcrdma_req *); 412 int rpcrdma_ep_post_recv(struct rpcrdma_ia *, struct rpcrdma_ep *, 413 struct rpcrdma_rep *); 414 415 /* 416 * Buffer calls - xprtrdma/verbs.c 417 */ 418 int rpcrdma_buffer_create(struct rpcrdma_xprt *); 419 void rpcrdma_buffer_destroy(struct rpcrdma_buffer *); 420 421 struct rpcrdma_mw *rpcrdma_get_mw(struct rpcrdma_xprt *); 422 void rpcrdma_put_mw(struct rpcrdma_xprt *, struct rpcrdma_mw *); 423 struct rpcrdma_req *rpcrdma_buffer_get(struct rpcrdma_buffer *); 424 void rpcrdma_buffer_put(struct rpcrdma_req *); 425 void rpcrdma_recv_buffer_get(struct rpcrdma_req *); 426 void rpcrdma_recv_buffer_put(struct rpcrdma_rep *); 427 428 struct rpcrdma_regbuf *rpcrdma_alloc_regbuf(struct rpcrdma_ia *, 429 size_t, gfp_t); 430 void rpcrdma_free_regbuf(struct rpcrdma_ia *, 431 struct rpcrdma_regbuf *); 432 433 unsigned int rpcrdma_max_segments(struct rpcrdma_xprt *); 434 435 int frwr_alloc_recovery_wq(void); 436 void frwr_destroy_recovery_wq(void); 437 438 /* 439 * Wrappers for chunk registration, shared by read/write chunk code. 440 */ 441 442 void rpcrdma_mapping_error(struct rpcrdma_mr_seg *); 443 444 static inline enum dma_data_direction 445 rpcrdma_data_dir(bool writing) 446 { 447 return writing ? DMA_FROM_DEVICE : DMA_TO_DEVICE; 448 } 449 450 static inline void 451 rpcrdma_map_one(struct ib_device *device, struct rpcrdma_mr_seg *seg, 452 enum dma_data_direction direction) 453 { 454 seg->mr_dir = direction; 455 seg->mr_dmalen = seg->mr_len; 456 457 if (seg->mr_page) 458 seg->mr_dma = ib_dma_map_page(device, 459 seg->mr_page, offset_in_page(seg->mr_offset), 460 seg->mr_dmalen, seg->mr_dir); 461 else 462 seg->mr_dma = ib_dma_map_single(device, 463 seg->mr_offset, 464 seg->mr_dmalen, seg->mr_dir); 465 466 if (ib_dma_mapping_error(device, seg->mr_dma)) 467 rpcrdma_mapping_error(seg); 468 } 469 470 static inline void 471 rpcrdma_unmap_one(struct ib_device *device, struct rpcrdma_mr_seg *seg) 472 { 473 if (seg->mr_page) 474 ib_dma_unmap_page(device, 475 seg->mr_dma, seg->mr_dmalen, seg->mr_dir); 476 else 477 ib_dma_unmap_single(device, 478 seg->mr_dma, seg->mr_dmalen, seg->mr_dir); 479 } 480 481 /* 482 * RPC/RDMA connection management calls - xprtrdma/rpc_rdma.c 483 */ 484 void rpcrdma_connect_worker(struct work_struct *); 485 void rpcrdma_conn_func(struct rpcrdma_ep *); 486 void rpcrdma_reply_handler(struct rpcrdma_rep *); 487 488 /* 489 * RPC/RDMA protocol calls - xprtrdma/rpc_rdma.c 490 */ 491 int rpcrdma_marshal_req(struct rpc_rqst *); 492 493 /* RPC/RDMA module init - xprtrdma/transport.c 494 */ 495 int xprt_rdma_init(void); 496 void xprt_rdma_cleanup(void); 497 498 /* Temporary NFS request map cache. Created in svc_rdma.c */ 499 extern struct kmem_cache *svc_rdma_map_cachep; 500 /* WR context cache. Created in svc_rdma.c */ 501 extern struct kmem_cache *svc_rdma_ctxt_cachep; 502 /* Workqueue created in svc_rdma.c */ 503 extern struct workqueue_struct *svc_rdma_wq; 504 505 #endif /* _LINUX_SUNRPC_XPRT_RDMA_H */ 506