RDS/IB+IW: Move recv processing to a tasklet
[linux-2.6.git] / net / rds / iw.h
1 #ifndef _RDS_IW_H
2 #define _RDS_IW_H
3
4 #include <rdma/ib_verbs.h>
5 #include <rdma/rdma_cm.h>
6 #include "rds.h"
7 #include "rdma_transport.h"
8
9 #define RDS_FASTREG_SIZE                20
10 #define RDS_FASTREG_POOL_SIZE           2048
11
12 #define RDS_IW_MAX_SGE                  8
13 #define RDS_IW_RECV_SGE                 2
14
15 #define RDS_IW_DEFAULT_RECV_WR          1024
16 #define RDS_IW_DEFAULT_SEND_WR          256
17
18 #define RDS_IW_SUPPORTED_PROTOCOLS      0x00000003      /* minor versions supported */
19
20 extern struct list_head rds_iw_devices;
21
22 /*
23  * IB posts RDS_FRAG_SIZE fragments of pages to the receive queues to
24  * try and minimize the amount of memory tied up both the device and
25  * socket receive queues.
26  */
27 /* page offset of the final full frag that fits in the page */
28 #define RDS_PAGE_LAST_OFF (((PAGE_SIZE  / RDS_FRAG_SIZE) - 1) * RDS_FRAG_SIZE)
29 struct rds_page_frag {
30         struct list_head        f_item;
31         struct page             *f_page;
32         unsigned long           f_offset;
33         dma_addr_t              f_mapped;
34 };
35
36 struct rds_iw_incoming {
37         struct list_head        ii_frags;
38         struct rds_incoming     ii_inc;
39 };
40
41 struct rds_iw_connect_private {
42         /* Add new fields at the end, and don't permute existing fields. */
43         __be32                  dp_saddr;
44         __be32                  dp_daddr;
45         u8                      dp_protocol_major;
46         u8                      dp_protocol_minor;
47         __be16                  dp_protocol_minor_mask; /* bitmask */
48         __be32                  dp_reserved1;
49         __be64                  dp_ack_seq;
50         __be32                  dp_credit;              /* non-zero enables flow ctl */
51 };
52
53 struct rds_iw_scatterlist {
54         struct scatterlist      *list;
55         unsigned int            len;
56         int                     dma_len;
57         unsigned int            dma_npages;
58         unsigned int            bytes;
59 };
60
61 struct rds_iw_mapping {
62         spinlock_t              m_lock; /* protect the mapping struct */
63         struct list_head        m_list;
64         struct rds_iw_mr        *m_mr;
65         uint32_t                m_rkey;
66         struct rds_iw_scatterlist m_sg;
67 };
68
69 struct rds_iw_send_work {
70         struct rds_message      *s_rm;
71
72         /* We should really put these into a union: */
73         struct rds_rdma_op      *s_op;
74         struct rds_iw_mapping   *s_mapping;
75         struct ib_mr            *s_mr;
76         struct ib_fast_reg_page_list *s_page_list;
77         unsigned char           s_remap_count;
78
79         struct ib_send_wr       s_wr;
80         struct ib_sge           s_sge[RDS_IW_MAX_SGE];
81         unsigned long           s_queued;
82 };
83
84 struct rds_iw_recv_work {
85         struct rds_iw_incoming  *r_iwinc;
86         struct rds_page_frag    *r_frag;
87         struct ib_recv_wr       r_wr;
88         struct ib_sge           r_sge[2];
89 };
90
91 struct rds_iw_work_ring {
92         u32             w_nr;
93         u32             w_alloc_ptr;
94         u32             w_alloc_ctr;
95         u32             w_free_ptr;
96         atomic_t        w_free_ctr;
97 };
98
99 struct rds_iw_device;
100
101 struct rds_iw_connection {
102
103         struct list_head        iw_node;
104         struct rds_iw_device    *rds_iwdev;
105         struct rds_connection   *conn;
106
107         /* alphabet soup, IBTA style */
108         struct rdma_cm_id       *i_cm_id;
109         struct ib_pd            *i_pd;
110         struct ib_mr            *i_mr;
111         struct ib_cq            *i_send_cq;
112         struct ib_cq            *i_recv_cq;
113
114         /* tx */
115         struct rds_iw_work_ring i_send_ring;
116         struct rds_message      *i_rm;
117         struct rds_header       *i_send_hdrs;
118         u64                     i_send_hdrs_dma;
119         struct rds_iw_send_work *i_sends;
120
121         /* rx */
122         struct tasklet_struct   i_recv_tasklet;
123         struct mutex            i_recv_mutex;
124         struct rds_iw_work_ring i_recv_ring;
125         struct rds_iw_incoming  *i_iwinc;
126         u32                     i_recv_data_rem;
127         struct rds_header       *i_recv_hdrs;
128         u64                     i_recv_hdrs_dma;
129         struct rds_iw_recv_work *i_recvs;
130         struct rds_page_frag    i_frag;
131         u64                     i_ack_recv;     /* last ACK received */
132
133         /* sending acks */
134         unsigned long           i_ack_flags;
135 #ifdef KERNEL_HAS_ATOMIC64
136         atomic64_t              i_ack_next;     /* next ACK to send */
137 #else
138         spinlock_t              i_ack_lock;     /* protect i_ack_next */
139         u64                     i_ack_next;     /* next ACK to send */
140 #endif
141         struct rds_header       *i_ack;
142         struct ib_send_wr       i_ack_wr;
143         struct ib_sge           i_ack_sge;
144         u64                     i_ack_dma;
145         unsigned long           i_ack_queued;
146
147         /* Flow control related information
148          *
149          * Our algorithm uses a pair variables that we need to access
150          * atomically - one for the send credits, and one posted
151          * recv credits we need to transfer to remote.
152          * Rather than protect them using a slow spinlock, we put both into
153          * a single atomic_t and update it using cmpxchg
154          */
155         atomic_t                i_credits;
156
157         /* Protocol version specific information */
158         unsigned int            i_flowctl:1;    /* enable/disable flow ctl */
159         unsigned int            i_dma_local_lkey:1;
160         unsigned int            i_fastreg_posted:1; /* fastreg posted on this connection */
161         /* Batched completions */
162         unsigned int            i_unsignaled_wrs;
163         long                    i_unsignaled_bytes;
164 };
165
166 /* This assumes that atomic_t is at least 32 bits */
167 #define IB_GET_SEND_CREDITS(v)  ((v) & 0xffff)
168 #define IB_GET_POST_CREDITS(v)  ((v) >> 16)
169 #define IB_SET_SEND_CREDITS(v)  ((v) & 0xffff)
170 #define IB_SET_POST_CREDITS(v)  ((v) << 16)
171
172 struct rds_iw_cm_id {
173         struct list_head        list;
174         struct rdma_cm_id       *cm_id;
175 };
176
177 struct rds_iw_device {
178         struct list_head        list;
179         struct list_head        cm_id_list;
180         struct list_head        conn_list;
181         struct ib_device        *dev;
182         struct ib_pd            *pd;
183         struct ib_mr            *mr;
184         struct rds_iw_mr_pool   *mr_pool;
185         int                     max_sge;
186         unsigned int            max_wrs;
187         unsigned int            dma_local_lkey:1;
188         spinlock_t              spinlock;       /* protect the above */
189 };
190
191 /* bits for i_ack_flags */
192 #define IB_ACK_IN_FLIGHT        0
193 #define IB_ACK_REQUESTED        1
194
195 /* Magic WR_ID for ACKs */
196 #define RDS_IW_ACK_WR_ID        ((u64)0xffffffffffffffffULL)
197 #define RDS_IW_FAST_REG_WR_ID   ((u64)0xefefefefefefefefULL)
198 #define RDS_IW_LOCAL_INV_WR_ID  ((u64)0xdfdfdfdfdfdfdfdfULL)
199
200 struct rds_iw_statistics {
201         uint64_t        s_iw_connect_raced;
202         uint64_t        s_iw_listen_closed_stale;
203         uint64_t        s_iw_tx_cq_call;
204         uint64_t        s_iw_tx_cq_event;
205         uint64_t        s_iw_tx_ring_full;
206         uint64_t        s_iw_tx_throttle;
207         uint64_t        s_iw_tx_sg_mapping_failure;
208         uint64_t        s_iw_tx_stalled;
209         uint64_t        s_iw_tx_credit_updates;
210         uint64_t        s_iw_rx_cq_call;
211         uint64_t        s_iw_rx_cq_event;
212         uint64_t        s_iw_rx_ring_empty;
213         uint64_t        s_iw_rx_refill_from_cq;
214         uint64_t        s_iw_rx_refill_from_thread;
215         uint64_t        s_iw_rx_alloc_limit;
216         uint64_t        s_iw_rx_credit_updates;
217         uint64_t        s_iw_ack_sent;
218         uint64_t        s_iw_ack_send_failure;
219         uint64_t        s_iw_ack_send_delayed;
220         uint64_t        s_iw_ack_send_piggybacked;
221         uint64_t        s_iw_ack_received;
222         uint64_t        s_iw_rdma_mr_alloc;
223         uint64_t        s_iw_rdma_mr_free;
224         uint64_t        s_iw_rdma_mr_used;
225         uint64_t        s_iw_rdma_mr_pool_flush;
226         uint64_t        s_iw_rdma_mr_pool_wait;
227         uint64_t        s_iw_rdma_mr_pool_depleted;
228 };
229
230 extern struct workqueue_struct *rds_iw_wq;
231
232 /*
233  * Fake ib_dma_sync_sg_for_{cpu,device} as long as ib_verbs.h
234  * doesn't define it.
235  */
236 static inline void rds_iw_dma_sync_sg_for_cpu(struct ib_device *dev,
237                 struct scatterlist *sg, unsigned int sg_dma_len, int direction)
238 {
239         unsigned int i;
240
241         for (i = 0; i < sg_dma_len; ++i) {
242                 ib_dma_sync_single_for_cpu(dev,
243                                 ib_sg_dma_address(dev, &sg[i]),
244                                 ib_sg_dma_len(dev, &sg[i]),
245                                 direction);
246         }
247 }
248 #define ib_dma_sync_sg_for_cpu  rds_iw_dma_sync_sg_for_cpu
249
250 static inline void rds_iw_dma_sync_sg_for_device(struct ib_device *dev,
251                 struct scatterlist *sg, unsigned int sg_dma_len, int direction)
252 {
253         unsigned int i;
254
255         for (i = 0; i < sg_dma_len; ++i) {
256                 ib_dma_sync_single_for_device(dev,
257                                 ib_sg_dma_address(dev, &sg[i]),
258                                 ib_sg_dma_len(dev, &sg[i]),
259                                 direction);
260         }
261 }
262 #define ib_dma_sync_sg_for_device       rds_iw_dma_sync_sg_for_device
263
264 static inline u32 rds_iw_local_dma_lkey(struct rds_iw_connection *ic)
265 {
266         return ic->i_dma_local_lkey ? ic->i_cm_id->device->local_dma_lkey : ic->i_mr->lkey;
267 }
268
269 /* ib.c */
270 extern struct rds_transport rds_iw_transport;
271 extern void rds_iw_add_one(struct ib_device *device);
272 extern void rds_iw_remove_one(struct ib_device *device);
273 extern struct ib_client rds_iw_client;
274
275 extern unsigned int fastreg_pool_size;
276 extern unsigned int fastreg_message_size;
277
278 extern spinlock_t iw_nodev_conns_lock;
279 extern struct list_head iw_nodev_conns;
280
281 /* ib_cm.c */
282 int rds_iw_conn_alloc(struct rds_connection *conn, gfp_t gfp);
283 void rds_iw_conn_free(void *arg);
284 int rds_iw_conn_connect(struct rds_connection *conn);
285 void rds_iw_conn_shutdown(struct rds_connection *conn);
286 void rds_iw_state_change(struct sock *sk);
287 int __init rds_iw_listen_init(void);
288 void rds_iw_listen_stop(void);
289 void __rds_iw_conn_error(struct rds_connection *conn, const char *, ...);
290 int rds_iw_cm_handle_connect(struct rdma_cm_id *cm_id,
291                              struct rdma_cm_event *event);
292 int rds_iw_cm_initiate_connect(struct rdma_cm_id *cm_id);
293 void rds_iw_cm_connect_complete(struct rds_connection *conn,
294                                 struct rdma_cm_event *event);
295
296
297 #define rds_iw_conn_error(conn, fmt...) \
298         __rds_iw_conn_error(conn, KERN_WARNING "RDS/IW: " fmt)
299
300 /* ib_rdma.c */
301 int rds_iw_update_cm_id(struct rds_iw_device *rds_iwdev, struct rdma_cm_id *cm_id);
302 void rds_iw_add_conn(struct rds_iw_device *rds_iwdev, struct rds_connection *conn);
303 void rds_iw_remove_conn(struct rds_iw_device *rds_iwdev, struct rds_connection *conn);
304 void __rds_iw_destroy_conns(struct list_head *list, spinlock_t *list_lock);
305 static inline void rds_iw_destroy_nodev_conns(void)
306 {
307         __rds_iw_destroy_conns(&iw_nodev_conns, &iw_nodev_conns_lock);
308 }
309 static inline void rds_iw_destroy_conns(struct rds_iw_device *rds_iwdev)
310 {
311         __rds_iw_destroy_conns(&rds_iwdev->conn_list, &rds_iwdev->spinlock);
312 }
313 struct rds_iw_mr_pool *rds_iw_create_mr_pool(struct rds_iw_device *);
314 void rds_iw_get_mr_info(struct rds_iw_device *rds_iwdev, struct rds_info_rdma_connection *iinfo);
315 void rds_iw_destroy_mr_pool(struct rds_iw_mr_pool *);
316 void *rds_iw_get_mr(struct scatterlist *sg, unsigned long nents,
317                     struct rds_sock *rs, u32 *key_ret);
318 void rds_iw_sync_mr(void *trans_private, int dir);
319 void rds_iw_free_mr(void *trans_private, int invalidate);
320 void rds_iw_flush_mrs(void);
321 void rds_iw_remove_cm_id(struct rds_iw_device *rds_iwdev, struct rdma_cm_id *cm_id);
322
323 /* ib_recv.c */
324 int __init rds_iw_recv_init(void);
325 void rds_iw_recv_exit(void);
326 int rds_iw_recv(struct rds_connection *conn);
327 int rds_iw_recv_refill(struct rds_connection *conn, gfp_t kptr_gfp,
328                        gfp_t page_gfp, int prefill);
329 void rds_iw_inc_purge(struct rds_incoming *inc);
330 void rds_iw_inc_free(struct rds_incoming *inc);
331 int rds_iw_inc_copy_to_user(struct rds_incoming *inc, struct iovec *iov,
332                              size_t size);
333 void rds_iw_recv_cq_comp_handler(struct ib_cq *cq, void *context);
334 void rds_iw_recv_tasklet_fn(unsigned long data);
335 void rds_iw_recv_init_ring(struct rds_iw_connection *ic);
336 void rds_iw_recv_clear_ring(struct rds_iw_connection *ic);
337 void rds_iw_recv_init_ack(struct rds_iw_connection *ic);
338 void rds_iw_attempt_ack(struct rds_iw_connection *ic);
339 void rds_iw_ack_send_complete(struct rds_iw_connection *ic);
340 u64 rds_iw_piggyb_ack(struct rds_iw_connection *ic);
341
342 /* ib_ring.c */
343 void rds_iw_ring_init(struct rds_iw_work_ring *ring, u32 nr);
344 void rds_iw_ring_resize(struct rds_iw_work_ring *ring, u32 nr);
345 u32 rds_iw_ring_alloc(struct rds_iw_work_ring *ring, u32 val, u32 *pos);
346 void rds_iw_ring_free(struct rds_iw_work_ring *ring, u32 val);
347 void rds_iw_ring_unalloc(struct rds_iw_work_ring *ring, u32 val);
348 int rds_iw_ring_empty(struct rds_iw_work_ring *ring);
349 int rds_iw_ring_low(struct rds_iw_work_ring *ring);
350 u32 rds_iw_ring_oldest(struct rds_iw_work_ring *ring);
351 u32 rds_iw_ring_completed(struct rds_iw_work_ring *ring, u32 wr_id, u32 oldest);
352 extern wait_queue_head_t rds_iw_ring_empty_wait;
353
354 /* ib_send.c */
355 void rds_iw_xmit_complete(struct rds_connection *conn);
356 int rds_iw_xmit(struct rds_connection *conn, struct rds_message *rm,
357                 unsigned int hdr_off, unsigned int sg, unsigned int off);
358 void rds_iw_send_cq_comp_handler(struct ib_cq *cq, void *context);
359 void rds_iw_send_init_ring(struct rds_iw_connection *ic);
360 void rds_iw_send_clear_ring(struct rds_iw_connection *ic);
361 int rds_iw_xmit_rdma(struct rds_connection *conn, struct rds_rdma_op *op);
362 void rds_iw_send_add_credits(struct rds_connection *conn, unsigned int credits);
363 void rds_iw_advertise_credits(struct rds_connection *conn, unsigned int posted);
364 int rds_iw_send_grab_credits(struct rds_iw_connection *ic, u32 wanted,
365                              u32 *adv_credits, int need_posted, int max_posted);
366
367 /* ib_stats.c */
368 DECLARE_PER_CPU(struct rds_iw_statistics, rds_iw_stats);
369 #define rds_iw_stats_inc(member) rds_stats_inc_which(rds_iw_stats, member)
370 unsigned int rds_iw_stats_info_copy(struct rds_info_iterator *iter,
371                                     unsigned int avail);
372
373 /* ib_sysctl.c */
374 int __init rds_iw_sysctl_init(void);
375 void rds_iw_sysctl_exit(void);
376 extern unsigned long rds_iw_sysctl_max_send_wr;
377 extern unsigned long rds_iw_sysctl_max_recv_wr;
378 extern unsigned long rds_iw_sysctl_max_unsig_wrs;
379 extern unsigned long rds_iw_sysctl_max_unsig_bytes;
380 extern unsigned long rds_iw_sysctl_max_recv_allocation;
381 extern unsigned int rds_iw_sysctl_flow_control;
382 extern ctl_table rds_iw_sysctl_table[];
383
384 /*
385  * Helper functions for getting/setting the header and data SGEs in
386  * RDS packets (not RDMA)
387  */
388 static inline struct ib_sge *
389 rds_iw_header_sge(struct rds_iw_connection *ic, struct ib_sge *sge)
390 {
391         return &sge[0];
392 }
393
394 static inline struct ib_sge *
395 rds_iw_data_sge(struct rds_iw_connection *ic, struct ib_sge *sge)
396 {
397         return &sge[1];
398 }
399
400 #endif