2 * Copyright (c) 2003-2007 Network Appliance, Inc. All rights reserved.
4 * This software is available to you under a choice of one of two
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40 #ifndef _LINUX_SUNRPC_XPRT_RDMA_H
41 #define _LINUX_SUNRPC_XPRT_RDMA_H
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 */
48 #include <rdma/rdma_cm.h> /* RDMA connection api */
49 #include <rdma/ib_verbs.h> /* RDMA verbs api */
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 */
55 #define RDMA_RESOLVE_TIMEOUT (5000) /* 5 seconds */
56 #define RDMA_CONNECT_RETRY_MAX (2) /* retries if no listener backlog */
59 * Interface Adapter -- one per transport instance
62 const struct rpcrdma_memreg_ops *ri_ops;
64 struct ib_device *ri_device;
65 struct rdma_cm_id *ri_id;
67 struct ib_mr *ri_dma_mr;
69 struct completion ri_done;
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;
78 * RDMA Endpoint -- one per transport instance
81 #define RPCRDMA_WC_BUDGET (128)
82 #define RPCRDMA_POLLSIZE (16)
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];
98 * Force a signaled SEND Work Request every so often,
99 * in case the provider needs to do some housekeeping.
101 #define RPCRDMA_MAX_UNSIGNALED_SENDS (32)
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)
106 /* Force completion handler to ignore the signal
108 #define RPCRDMA_IGNORE_COMPLETION (0ULL)
110 /* Registered buffer -- registered kmalloc'd memory for RDMA SEND/RECV
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.
116 struct rpcrdma_regbuf {
118 struct rpcrdma_req *rg_owner;
119 struct ib_sge rg_iov;
120 __be32 rg_base[0] __attribute__ ((aligned(256)));
124 rdmab_addr(struct rpcrdma_regbuf *rb)
126 return rb->rg_iov.addr;
130 rdmab_length(struct rpcrdma_regbuf *rb)
132 return rb->rg_iov.length;
136 rdmab_lkey(struct rpcrdma_regbuf *rb)
138 return rb->rg_iov.lkey;
141 static inline struct rpcrdma_msg *
142 rdmab_to_msg(struct rpcrdma_regbuf *rb)
144 return (struct rpcrdma_msg *)rb->rg_base;
148 * struct rpcrdma_rep -- this structure encapsulates state required to recv
149 * and complete a reply, asychronously. It needs several pieces of
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)
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.
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.
164 #define RPCRDMA_MAX_DATA_SEGS ((1 * 1024 * 1024) / PAGE_SIZE)
165 #define RPCRDMA_MAX_SEGS (RPCRDMA_MAX_DATA_SEGS + 2) /* head+tail = 2 */
167 struct rpcrdma_buffer;
171 struct ib_device *rr_device;
172 struct rpcrdma_xprt *rr_rxprt;
173 struct list_head rr_list;
174 struct rpcrdma_regbuf *rr_rdmabuf;
178 * struct rpcrdma_mw - external memory region metadata
180 * An external memory region is any buffer or page that is registered
181 * on the fly (ie, not pre-registered).
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.
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 */
196 struct rpcrdma_frmr {
197 struct ib_fast_reg_page_list *fr_pgl;
199 enum rpcrdma_frmr_state fr_state;
200 struct work_struct fr_work;
201 struct rpcrdma_xprt *fr_xprt;
211 struct rpcrdma_fmr fmr;
212 struct rpcrdma_frmr frmr;
214 void (*mw_sendcompletion)(struct ib_wc *);
215 struct list_head mw_list;
216 struct list_head mw_all;
220 * struct rpcrdma_req -- structure central to the request/reply sequence.
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.
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.
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
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.
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 */
256 #define RPCRDMA_MAX_IOVS (2)
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];
270 static inline struct rpcrdma_req *
271 rpcr_to_rdmar(struct rpc_rqst *rqst)
273 void *buffer = rqst->rq_buffer;
274 struct rpcrdma_regbuf *rb;
276 rb = container_of(buffer, struct rpcrdma_regbuf, rg_base);
281 * struct rpcrdma_buffer -- holds list/queue of pre-registered memory for
282 * inline requests/replies, and client/server credits.
284 * One of these is associated with a transport instance
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;
292 spinlock_t rb_lock; /* protect buf arrays */
296 struct rpcrdma_req **rb_send_bufs;
297 struct rpcrdma_rep **rb_recv_bufs;
299 #define rdmab_to_ia(b) (&container_of((b), struct rpcrdma_xprt, rx_buf)->rx_ia)
302 * Internal structure for transport instance creation. This
303 * exists primarily for modularity.
305 * This data should be set with mount options
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 */
317 #define RPCRDMA_INLINE_READ_THRESHOLD(rq) \
318 (rpcx_to_rdmad(rq->rq_xprt).inline_rsize)
320 #define RPCRDMA_INLINE_WRITE_THRESHOLD(rq)\
321 (rpcx_to_rdmad(rq->rq_xprt).inline_wsize)
323 #define RPCRDMA_INLINE_PAD_VALUE(rq)\
324 rpcx_to_rdmad(rq->rq_xprt).padding
327 * Statistics for RPCRDMA
329 struct rpcrdma_stats {
330 unsigned long read_chunk_count;
331 unsigned long write_chunk_count;
332 unsigned long reply_chunk_count;
334 unsigned long long total_rdma_request;
335 unsigned long long total_rdma_reply;
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;
346 * Per-registration mode operations
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 *,
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;
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;
368 * RPCRDMA transport -- encapsulates the structures above for
369 * integration with RPC.
371 * The contained structures are embedded, not pointers,
372 * for convenience. This structure need not be visible externally.
374 * It is allocated and initialized during mount, and released
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;
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)
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;
396 * Interface Adapter calls - xprtrdma/verbs.c
398 int rpcrdma_ia_open(struct rpcrdma_xprt *, struct sockaddr *, int);
399 void rpcrdma_ia_close(struct rpcrdma_ia *);
402 * Endpoint calls - xprtrdma/verbs.c
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 *);
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 *);
416 * Buffer calls - xprtrdma/verbs.c
418 int rpcrdma_buffer_create(struct rpcrdma_xprt *);
419 void rpcrdma_buffer_destroy(struct rpcrdma_buffer *);
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 *);
428 struct rpcrdma_regbuf *rpcrdma_alloc_regbuf(struct rpcrdma_ia *,
430 void rpcrdma_free_regbuf(struct rpcrdma_ia *,
431 struct rpcrdma_regbuf *);
433 unsigned int rpcrdma_max_segments(struct rpcrdma_xprt *);
435 int frwr_alloc_recovery_wq(void);
436 void frwr_destroy_recovery_wq(void);
439 * Wrappers for chunk registration, shared by read/write chunk code.
442 void rpcrdma_mapping_error(struct rpcrdma_mr_seg *);
444 static inline enum dma_data_direction
445 rpcrdma_data_dir(bool writing)
447 return writing ? DMA_FROM_DEVICE : DMA_TO_DEVICE;
451 rpcrdma_map_one(struct ib_device *device, struct rpcrdma_mr_seg *seg,
452 enum dma_data_direction direction)
454 seg->mr_dir = direction;
455 seg->mr_dmalen = seg->mr_len;
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);
462 seg->mr_dma = ib_dma_map_single(device,
464 seg->mr_dmalen, seg->mr_dir);
466 if (ib_dma_mapping_error(device, seg->mr_dma))
467 rpcrdma_mapping_error(seg);
471 rpcrdma_unmap_one(struct ib_device *device, struct rpcrdma_mr_seg *seg)
474 ib_dma_unmap_page(device,
475 seg->mr_dma, seg->mr_dmalen, seg->mr_dir);
477 ib_dma_unmap_single(device,
478 seg->mr_dma, seg->mr_dmalen, seg->mr_dir);
482 * RPC/RDMA connection management calls - xprtrdma/rpc_rdma.c
484 void rpcrdma_connect_worker(struct work_struct *);
485 void rpcrdma_conn_func(struct rpcrdma_ep *);
486 void rpcrdma_reply_handler(struct rpcrdma_rep *);
489 * RPC/RDMA protocol calls - xprtrdma/rpc_rdma.c
491 int rpcrdma_marshal_req(struct rpc_rqst *);
493 /* RPC/RDMA module init - xprtrdma/transport.c
495 int xprt_rdma_init(void);
496 void xprt_rdma_cleanup(void);
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;
505 #endif /* _LINUX_SUNRPC_XPRT_RDMA_H */