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 struct completion ri_done; 69 int ri_async_rc; 70 unsigned int ri_max_frmr_depth; 71 struct ib_device_attr ri_devattr; 72 struct ib_qp_attr ri_qp_attr; 73 struct ib_qp_init_attr ri_qp_init_attr; 74 }; 75 76 /* 77 * RDMA Endpoint -- one per transport instance 78 */ 79 80 #define RPCRDMA_WC_BUDGET (128) 81 #define RPCRDMA_POLLSIZE (16) 82 83 struct rpcrdma_ep { 84 atomic_t rep_cqcount; 85 int rep_cqinit; 86 int rep_connected; 87 struct ib_qp_init_attr rep_attr; 88 wait_queue_head_t rep_connect_wait; 89 struct rdma_conn_param rep_remote_cma; 90 struct sockaddr_storage rep_remote_addr; 91 struct delayed_work rep_connect_worker; 92 struct ib_wc rep_send_wcs[RPCRDMA_POLLSIZE]; 93 struct ib_wc rep_recv_wcs[RPCRDMA_POLLSIZE]; 94 }; 95 96 /* 97 * Force a signaled SEND Work Request every so often, 98 * in case the provider needs to do some housekeeping. 99 */ 100 #define RPCRDMA_MAX_UNSIGNALED_SENDS (32) 101 102 #define INIT_CQCOUNT(ep) atomic_set(&(ep)->rep_cqcount, (ep)->rep_cqinit) 103 #define DECR_CQCOUNT(ep) atomic_sub_return(1, &(ep)->rep_cqcount) 104 105 /* Force completion handler to ignore the signal 106 */ 107 #define RPCRDMA_IGNORE_COMPLETION (0ULL) 108 109 /* Registered buffer -- registered kmalloc'd memory for RDMA SEND/RECV 110 * 111 * The below structure appears at the front of a large region of kmalloc'd 112 * memory, which always starts on a good alignment boundary. 113 */ 114 115 struct rpcrdma_regbuf { 116 size_t rg_size; 117 struct rpcrdma_req *rg_owner; 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 /* 147 * struct rpcrdma_rep -- this structure encapsulates state required to recv 148 * and complete a reply, asychronously. It needs several pieces of 149 * state: 150 * o recv buffer (posted to provider) 151 * o ib_sge (also donated to provider) 152 * o status of reply (length, success or not) 153 * o bookkeeping state to get run by tasklet (list, etc) 154 * 155 * These are allocated during initialization, per-transport instance; 156 * however, the tasklet execution list itself is global, as it should 157 * always be pretty short. 158 * 159 * N of these are associated with a transport instance, and stored in 160 * struct rpcrdma_buffer. N is the max number of outstanding requests. 161 */ 162 163 #define RPCRDMA_MAX_DATA_SEGS ((1 * 1024 * 1024) / PAGE_SIZE) 164 #define RPCRDMA_MAX_SEGS (RPCRDMA_MAX_DATA_SEGS + 2) /* head+tail = 2 */ 165 166 struct rpcrdma_buffer; 167 168 struct rpcrdma_rep { 169 unsigned int rr_len; 170 struct ib_device *rr_device; 171 struct rpcrdma_xprt *rr_rxprt; 172 struct list_head rr_list; 173 struct rpcrdma_regbuf *rr_rdmabuf; 174 }; 175 176 /* 177 * struct rpcrdma_mw - external memory region metadata 178 * 179 * An external memory region is any buffer or page that is registered 180 * on the fly (ie, not pre-registered). 181 * 182 * Each rpcrdma_buffer has a list of free MWs anchored in rb_mws. During 183 * call_allocate, rpcrdma_buffer_get() assigns one to each segment in 184 * an rpcrdma_req. Then rpcrdma_register_external() grabs these to keep 185 * track of registration metadata while each RPC is pending. 186 * rpcrdma_deregister_external() uses this metadata to unmap and 187 * release these resources when an RPC is complete. 188 */ 189 enum rpcrdma_frmr_state { 190 FRMR_IS_INVALID, /* ready to be used */ 191 FRMR_IS_VALID, /* in use */ 192 FRMR_IS_STALE, /* failed completion */ 193 }; 194 195 struct rpcrdma_frmr { 196 struct ib_fast_reg_page_list *fr_pgl; 197 struct ib_mr *fr_mr; 198 enum rpcrdma_frmr_state fr_state; 199 struct work_struct fr_work; 200 struct rpcrdma_xprt *fr_xprt; 201 }; 202 203 struct rpcrdma_fmr { 204 struct ib_fmr *fmr; 205 u64 *physaddrs; 206 }; 207 208 struct rpcrdma_mw { 209 union { 210 struct rpcrdma_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 #define RPCRDMA_MAX_IOVS (2) 256 257 struct rpcrdma_req { 258 unsigned int rl_niovs; 259 unsigned int rl_nchunks; 260 unsigned int rl_connect_cookie; 261 struct rpcrdma_buffer *rl_buffer; 262 struct rpcrdma_rep *rl_reply;/* holder for reply buffer */ 263 struct ib_sge rl_send_iov[RPCRDMA_MAX_IOVS]; 264 struct rpcrdma_regbuf *rl_rdmabuf; 265 struct rpcrdma_regbuf *rl_sendbuf; 266 struct rpcrdma_mr_seg rl_segments[RPCRDMA_MAX_SEGS]; 267 }; 268 269 static inline struct rpcrdma_req * 270 rpcr_to_rdmar(struct rpc_rqst *rqst) 271 { 272 void *buffer = rqst->rq_buffer; 273 struct rpcrdma_regbuf *rb; 274 275 rb = container_of(buffer, struct rpcrdma_regbuf, rg_base); 276 return rb->rg_owner; 277 } 278 279 /* 280 * struct rpcrdma_buffer -- holds list/queue of pre-registered memory for 281 * inline requests/replies, and client/server credits. 282 * 283 * One of these is associated with a transport instance 284 */ 285 struct rpcrdma_buffer { 286 spinlock_t rb_mwlock; /* protect rb_mws list */ 287 struct list_head rb_mws; 288 struct list_head rb_all; 289 char *rb_pool; 290 291 spinlock_t rb_lock; /* protect buf arrays */ 292 u32 rb_max_requests; 293 int rb_send_index; 294 int rb_recv_index; 295 struct rpcrdma_req **rb_send_bufs; 296 struct rpcrdma_rep **rb_recv_bufs; 297 }; 298 #define rdmab_to_ia(b) (&container_of((b), struct rpcrdma_xprt, rx_buf)->rx_ia) 299 300 /* 301 * Internal structure for transport instance creation. This 302 * exists primarily for modularity. 303 * 304 * This data should be set with mount options 305 */ 306 struct rpcrdma_create_data_internal { 307 struct sockaddr_storage addr; /* RDMA server address */ 308 unsigned int max_requests; /* max requests (slots) in flight */ 309 unsigned int rsize; /* mount rsize - max read hdr+data */ 310 unsigned int wsize; /* mount wsize - max write hdr+data */ 311 unsigned int inline_rsize; /* max non-rdma read data payload */ 312 unsigned int inline_wsize; /* max non-rdma write data payload */ 313 unsigned int padding; /* non-rdma write header padding */ 314 }; 315 316 #define RPCRDMA_INLINE_READ_THRESHOLD(rq) \ 317 (rpcx_to_rdmad(rq->rq_xprt).inline_rsize) 318 319 #define RPCRDMA_INLINE_WRITE_THRESHOLD(rq)\ 320 (rpcx_to_rdmad(rq->rq_xprt).inline_wsize) 321 322 #define RPCRDMA_INLINE_PAD_VALUE(rq)\ 323 rpcx_to_rdmad(rq->rq_xprt).padding 324 325 /* 326 * Statistics for RPCRDMA 327 */ 328 struct rpcrdma_stats { 329 unsigned long read_chunk_count; 330 unsigned long write_chunk_count; 331 unsigned long reply_chunk_count; 332 333 unsigned long long total_rdma_request; 334 unsigned long long total_rdma_reply; 335 336 unsigned long long pullup_copy_count; 337 unsigned long long fixup_copy_count; 338 unsigned long hardway_register_count; 339 unsigned long failed_marshal_count; 340 unsigned long bad_reply_count; 341 unsigned long nomsg_call_count; 342 }; 343 344 /* 345 * Per-registration mode operations 346 */ 347 struct rpcrdma_xprt; 348 struct rpcrdma_memreg_ops { 349 int (*ro_map)(struct rpcrdma_xprt *, 350 struct rpcrdma_mr_seg *, int, bool); 351 int (*ro_unmap)(struct rpcrdma_xprt *, 352 struct rpcrdma_mr_seg *); 353 int (*ro_open)(struct rpcrdma_ia *, 354 struct rpcrdma_ep *, 355 struct rpcrdma_create_data_internal *); 356 size_t (*ro_maxpages)(struct rpcrdma_xprt *); 357 int (*ro_init)(struct rpcrdma_xprt *); 358 void (*ro_destroy)(struct rpcrdma_buffer *); 359 const char *ro_displayname; 360 }; 361 362 extern const struct rpcrdma_memreg_ops rpcrdma_fmr_memreg_ops; 363 extern const struct rpcrdma_memreg_ops rpcrdma_frwr_memreg_ops; 364 extern const struct rpcrdma_memreg_ops rpcrdma_physical_memreg_ops; 365 366 /* 367 * RPCRDMA transport -- encapsulates the structures above for 368 * integration with RPC. 369 * 370 * The contained structures are embedded, not pointers, 371 * for convenience. This structure need not be visible externally. 372 * 373 * It is allocated and initialized during mount, and released 374 * during unmount. 375 */ 376 struct rpcrdma_xprt { 377 struct rpc_xprt rx_xprt; 378 struct rpcrdma_ia rx_ia; 379 struct rpcrdma_ep rx_ep; 380 struct rpcrdma_buffer rx_buf; 381 struct rpcrdma_create_data_internal rx_data; 382 struct delayed_work rx_connect_worker; 383 struct rpcrdma_stats rx_stats; 384 }; 385 386 #define rpcx_to_rdmax(x) container_of(x, struct rpcrdma_xprt, rx_xprt) 387 #define rpcx_to_rdmad(x) (rpcx_to_rdmax(x)->rx_data) 388 389 /* Setting this to 0 ensures interoperability with early servers. 390 * Setting this to 1 enhances certain unaligned read/write performance. 391 * Default is 0, see sysctl entry and rpc_rdma.c rpcrdma_convert_iovs() */ 392 extern int xprt_rdma_pad_optimize; 393 394 /* 395 * Interface Adapter calls - xprtrdma/verbs.c 396 */ 397 int rpcrdma_ia_open(struct rpcrdma_xprt *, struct sockaddr *, int); 398 void rpcrdma_ia_close(struct rpcrdma_ia *); 399 400 /* 401 * Endpoint calls - xprtrdma/verbs.c 402 */ 403 int rpcrdma_ep_create(struct rpcrdma_ep *, struct rpcrdma_ia *, 404 struct rpcrdma_create_data_internal *); 405 void rpcrdma_ep_destroy(struct rpcrdma_ep *, struct rpcrdma_ia *); 406 int rpcrdma_ep_connect(struct rpcrdma_ep *, struct rpcrdma_ia *); 407 void rpcrdma_ep_disconnect(struct rpcrdma_ep *, struct rpcrdma_ia *); 408 409 int rpcrdma_ep_post(struct rpcrdma_ia *, struct rpcrdma_ep *, 410 struct rpcrdma_req *); 411 int rpcrdma_ep_post_recv(struct rpcrdma_ia *, struct rpcrdma_ep *, 412 struct rpcrdma_rep *); 413 414 /* 415 * Buffer calls - xprtrdma/verbs.c 416 */ 417 int rpcrdma_buffer_create(struct rpcrdma_xprt *); 418 void rpcrdma_buffer_destroy(struct rpcrdma_buffer *); 419 420 struct rpcrdma_mw *rpcrdma_get_mw(struct rpcrdma_xprt *); 421 void rpcrdma_put_mw(struct rpcrdma_xprt *, struct rpcrdma_mw *); 422 struct rpcrdma_req *rpcrdma_buffer_get(struct rpcrdma_buffer *); 423 void rpcrdma_buffer_put(struct rpcrdma_req *); 424 void rpcrdma_recv_buffer_get(struct rpcrdma_req *); 425 void rpcrdma_recv_buffer_put(struct rpcrdma_rep *); 426 427 struct rpcrdma_regbuf *rpcrdma_alloc_regbuf(struct rpcrdma_ia *, 428 size_t, gfp_t); 429 void rpcrdma_free_regbuf(struct rpcrdma_ia *, 430 struct rpcrdma_regbuf *); 431 432 unsigned int rpcrdma_max_segments(struct rpcrdma_xprt *); 433 434 int frwr_alloc_recovery_wq(void); 435 void frwr_destroy_recovery_wq(void); 436 437 /* 438 * Wrappers for chunk registration, shared by read/write chunk code. 439 */ 440 441 void rpcrdma_mapping_error(struct rpcrdma_mr_seg *); 442 443 static inline enum dma_data_direction 444 rpcrdma_data_dir(bool writing) 445 { 446 return writing ? DMA_FROM_DEVICE : DMA_TO_DEVICE; 447 } 448 449 static inline void 450 rpcrdma_map_one(struct ib_device *device, struct rpcrdma_mr_seg *seg, 451 enum dma_data_direction direction) 452 { 453 seg->mr_dir = direction; 454 seg->mr_dmalen = seg->mr_len; 455 456 if (seg->mr_page) 457 seg->mr_dma = ib_dma_map_page(device, 458 seg->mr_page, offset_in_page(seg->mr_offset), 459 seg->mr_dmalen, seg->mr_dir); 460 else 461 seg->mr_dma = ib_dma_map_single(device, 462 seg->mr_offset, 463 seg->mr_dmalen, seg->mr_dir); 464 465 if (ib_dma_mapping_error(device, seg->mr_dma)) 466 rpcrdma_mapping_error(seg); 467 } 468 469 static inline void 470 rpcrdma_unmap_one(struct ib_device *device, struct rpcrdma_mr_seg *seg) 471 { 472 if (seg->mr_page) 473 ib_dma_unmap_page(device, 474 seg->mr_dma, seg->mr_dmalen, seg->mr_dir); 475 else 476 ib_dma_unmap_single(device, 477 seg->mr_dma, seg->mr_dmalen, seg->mr_dir); 478 } 479 480 /* 481 * RPC/RDMA connection management calls - xprtrdma/rpc_rdma.c 482 */ 483 void rpcrdma_connect_worker(struct work_struct *); 484 void rpcrdma_conn_func(struct rpcrdma_ep *); 485 void rpcrdma_reply_handler(struct rpcrdma_rep *); 486 487 /* 488 * RPC/RDMA protocol calls - xprtrdma/rpc_rdma.c 489 */ 490 int rpcrdma_marshal_req(struct rpc_rqst *); 491 492 /* RPC/RDMA module init - xprtrdma/transport.c 493 */ 494 int xprt_rdma_init(void); 495 void xprt_rdma_cleanup(void); 496 497 /* Temporary NFS request map cache. Created in svc_rdma.c */ 498 extern struct kmem_cache *svc_rdma_map_cachep; 499 /* WR context cache. Created in svc_rdma.c */ 500 extern struct kmem_cache *svc_rdma_ctxt_cachep; 501 /* Workqueue created in svc_rdma.c */ 502 extern struct workqueue_struct *svc_rdma_wq; 503 504 #endif /* _LINUX_SUNRPC_XPRT_RDMA_H */ 505