bpf: Avoid hashtab deadlock with map_locked
[linux-2.6-microblaze.git] / net / smc / smc_core.h
1 /* SPDX-License-Identifier: GPL-2.0 */
2 /*
3  * Shared Memory Communications over RDMA (SMC-R) and RoCE
4  *
5  *  Definitions for SMC Connections, Link Groups and Links
6  *
7  *  Copyright IBM Corp. 2016
8  *
9  *  Author(s):  Ursula Braun <ubraun@linux.vnet.ibm.com>
10  */
11
12 #ifndef _SMC_CORE_H
13 #define _SMC_CORE_H
14
15 #include <linux/atomic.h>
16 #include <rdma/ib_verbs.h>
17
18 #include "smc.h"
19 #include "smc_ib.h"
20
21 #define SMC_RMBS_PER_LGR_MAX    255     /* max. # of RMBs per link group */
22
23 struct smc_lgr_list {                   /* list of link group definition */
24         struct list_head        list;
25         spinlock_t              lock;   /* protects list of link groups */
26         u32                     num;    /* unique link group number */
27 };
28
29 enum smc_lgr_role {             /* possible roles of a link group */
30         SMC_CLNT,       /* client */
31         SMC_SERV        /* server */
32 };
33
34 enum smc_link_state {                   /* possible states of a link */
35         SMC_LNK_UNUSED,         /* link is unused */
36         SMC_LNK_INACTIVE,       /* link is inactive */
37         SMC_LNK_ACTIVATING,     /* link is being activated */
38         SMC_LNK_ACTIVE,         /* link is active */
39 };
40
41 #define SMC_WR_BUF_SIZE         48      /* size of work request buffer */
42
43 struct smc_wr_buf {
44         u8      raw[SMC_WR_BUF_SIZE];
45 };
46
47 #define SMC_WR_REG_MR_WAIT_TIME (5 * HZ)/* wait time for ib_wr_reg_mr result */
48
49 enum smc_wr_reg_state {
50         POSTED,         /* ib_wr_reg_mr request posted */
51         CONFIRMED,      /* ib_wr_reg_mr response: successful */
52         FAILED          /* ib_wr_reg_mr response: failure */
53 };
54
55 struct smc_rdma_sge {                           /* sges for RDMA writes */
56         struct ib_sge           wr_tx_rdma_sge[SMC_IB_MAX_SEND_SGE];
57 };
58
59 #define SMC_MAX_RDMA_WRITES     2               /* max. # of RDMA writes per
60                                                  * message send
61                                                  */
62
63 struct smc_rdma_sges {                          /* sges per message send */
64         struct smc_rdma_sge     tx_rdma_sge[SMC_MAX_RDMA_WRITES];
65 };
66
67 struct smc_rdma_wr {                            /* work requests per message
68                                                  * send
69                                                  */
70         struct ib_rdma_wr       wr_tx_rdma[SMC_MAX_RDMA_WRITES];
71 };
72
73 #define SMC_LGR_ID_SIZE         4
74
75 struct smc_link {
76         struct smc_ib_device    *smcibdev;      /* ib-device */
77         u8                      ibport;         /* port - values 1 | 2 */
78         struct ib_pd            *roce_pd;       /* IB protection domain,
79                                                  * unique for every RoCE QP
80                                                  */
81         struct ib_qp            *roce_qp;       /* IB queue pair */
82         struct ib_qp_attr       qp_attr;        /* IB queue pair attributes */
83
84         struct smc_wr_buf       *wr_tx_bufs;    /* WR send payload buffers */
85         struct ib_send_wr       *wr_tx_ibs;     /* WR send meta data */
86         struct ib_sge           *wr_tx_sges;    /* WR send gather meta data */
87         struct smc_rdma_sges    *wr_tx_rdma_sges;/*RDMA WRITE gather meta data*/
88         struct smc_rdma_wr      *wr_tx_rdmas;   /* WR RDMA WRITE */
89         struct smc_wr_tx_pend   *wr_tx_pends;   /* WR send waiting for CQE */
90         struct completion       *wr_tx_compl;   /* WR send CQE completion */
91         /* above four vectors have wr_tx_cnt elements and use the same index */
92         dma_addr_t              wr_tx_dma_addr; /* DMA address of wr_tx_bufs */
93         atomic_long_t           wr_tx_id;       /* seq # of last sent WR */
94         unsigned long           *wr_tx_mask;    /* bit mask of used indexes */
95         u32                     wr_tx_cnt;      /* number of WR send buffers */
96         wait_queue_head_t       wr_tx_wait;     /* wait for free WR send buf */
97
98         struct smc_wr_buf       *wr_rx_bufs;    /* WR recv payload buffers */
99         struct ib_recv_wr       *wr_rx_ibs;     /* WR recv meta data */
100         struct ib_sge           *wr_rx_sges;    /* WR recv scatter meta data */
101         /* above three vectors have wr_rx_cnt elements and use the same index */
102         dma_addr_t              wr_rx_dma_addr; /* DMA address of wr_rx_bufs */
103         u64                     wr_rx_id;       /* seq # of last recv WR */
104         u32                     wr_rx_cnt;      /* number of WR recv buffers */
105         unsigned long           wr_rx_tstamp;   /* jiffies when last buf rx */
106
107         struct ib_reg_wr        wr_reg;         /* WR register memory region */
108         wait_queue_head_t       wr_reg_wait;    /* wait for wr_reg result */
109         enum smc_wr_reg_state   wr_reg_state;   /* state of wr_reg request */
110
111         u8                      gid[SMC_GID_SIZE];/* gid matching used vlan id*/
112         u8                      sgid_index;     /* gid index for vlan id      */
113         u32                     peer_qpn;       /* QP number of peer */
114         enum ib_mtu             path_mtu;       /* used mtu */
115         enum ib_mtu             peer_mtu;       /* mtu size of peer */
116         u32                     psn_initial;    /* QP tx initial packet seqno */
117         u32                     peer_psn;       /* QP rx initial packet seqno */
118         u8                      peer_mac[ETH_ALEN];     /* = gid[8:10||13:15] */
119         u8                      peer_gid[SMC_GID_SIZE]; /* gid of peer*/
120         u8                      link_id;        /* unique # within link group */
121         u8                      link_uid[SMC_LGR_ID_SIZE]; /* unique lnk id */
122         u8                      peer_link_uid[SMC_LGR_ID_SIZE]; /* peer uid */
123         u8                      link_idx;       /* index in lgr link array */
124         u8                      link_is_asym;   /* is link asymmetric? */
125         struct smc_link_group   *lgr;           /* parent link group */
126         struct work_struct      link_down_wrk;  /* wrk to bring link down */
127
128         enum smc_link_state     state;          /* state of link */
129         struct delayed_work     llc_testlink_wrk; /* testlink worker */
130         struct completion       llc_testlink_resp; /* wait for rx of testlink */
131         int                     llc_testlink_time; /* testlink interval */
132 };
133
134 /* For now we just allow one parallel link per link group. The SMC protocol
135  * allows more (up to 8).
136  */
137 #define SMC_LINKS_PER_LGR_MAX   3
138 #define SMC_SINGLE_LINK         0
139
140 /* tx/rx buffer list element for sndbufs list and rmbs list of a lgr */
141 struct smc_buf_desc {
142         struct list_head        list;
143         void                    *cpu_addr;      /* virtual address of buffer */
144         struct page             *pages;
145         int                     len;            /* length of buffer */
146         u32                     used;           /* currently used / unused */
147         union {
148                 struct { /* SMC-R */
149                         struct sg_table sgt[SMC_LINKS_PER_LGR_MAX];
150                                         /* virtual buffer */
151                         struct ib_mr    *mr_rx[SMC_LINKS_PER_LGR_MAX];
152                                         /* for rmb only: memory region
153                                          * incl. rkey provided to peer
154                                          */
155                         u32             order;  /* allocation order */
156
157                         u8              is_conf_rkey;
158                                         /* confirm_rkey done */
159                         u8              is_reg_mr[SMC_LINKS_PER_LGR_MAX];
160                                         /* mem region registered */
161                         u8              is_map_ib[SMC_LINKS_PER_LGR_MAX];
162                                         /* mem region mapped to lnk */
163                         u8              is_reg_err;
164                                         /* buffer registration err */
165                 };
166                 struct { /* SMC-D */
167                         unsigned short  sba_idx;
168                                         /* SBA index number */
169                         u64             token;
170                                         /* DMB token number */
171                         dma_addr_t      dma_addr;
172                                         /* DMA address */
173                 };
174         };
175 };
176
177 struct smc_rtoken {                             /* address/key of remote RMB */
178         u64                     dma_addr;
179         u32                     rkey;
180 };
181
182 #define SMC_BUF_MIN_SIZE        16384   /* minimum size of an RMB */
183 #define SMC_RMBE_SIZES          16      /* number of distinct RMBE sizes */
184 /* theoretically, the RFC states that largest size would be 512K,
185  * i.e. compressed 5 and thus 6 sizes (0..5), despite
186  * struct smc_clc_msg_accept_confirm.rmbe_size being a 4 bit value (0..15)
187  */
188
189 struct smcd_dev;
190
191 enum smc_lgr_type {                             /* redundancy state of lgr */
192         SMC_LGR_NONE,                   /* no active links, lgr to be deleted */
193         SMC_LGR_SINGLE,                 /* 1 active RNIC on each peer */
194         SMC_LGR_SYMMETRIC,              /* 2 active RNICs on each peer */
195         SMC_LGR_ASYMMETRIC_PEER,        /* local has 2, peer 1 active RNICs */
196         SMC_LGR_ASYMMETRIC_LOCAL,       /* local has 1, peer 2 active RNICs */
197 };
198
199 enum smc_llc_flowtype {
200         SMC_LLC_FLOW_NONE       = 0,
201         SMC_LLC_FLOW_ADD_LINK   = 2,
202         SMC_LLC_FLOW_DEL_LINK   = 4,
203         SMC_LLC_FLOW_RKEY       = 6,
204 };
205
206 struct smc_llc_qentry;
207
208 struct smc_llc_flow {
209         enum smc_llc_flowtype type;
210         struct smc_llc_qentry *qentry;
211 };
212
213 struct smc_link_group {
214         struct list_head        list;
215         struct rb_root          conns_all;      /* connection tree */
216         rwlock_t                conns_lock;     /* protects conns_all */
217         unsigned int            conns_num;      /* current # of connections */
218         unsigned short          vlan_id;        /* vlan id of link group */
219
220         struct list_head        sndbufs[SMC_RMBE_SIZES];/* tx buffers */
221         struct mutex            sndbufs_lock;   /* protects tx buffers */
222         struct list_head        rmbs[SMC_RMBE_SIZES];   /* rx buffers */
223         struct mutex            rmbs_lock;      /* protects rx buffers */
224
225         u8                      id[SMC_LGR_ID_SIZE];    /* unique lgr id */
226         struct delayed_work     free_work;      /* delayed freeing of an lgr */
227         struct work_struct      terminate_work; /* abnormal lgr termination */
228         struct workqueue_struct *tx_wq;         /* wq for conn. tx workers */
229         u8                      sync_err : 1;   /* lgr no longer fits to peer */
230         u8                      terminating : 1;/* lgr is terminating */
231         u8                      freeing : 1;    /* lgr is being freed */
232
233         bool                    is_smcd;        /* SMC-R or SMC-D */
234         u8                      smc_version;
235         u8                      negotiated_eid[SMC_MAX_EID_LEN];
236         u8                      peer_os;        /* peer operating system */
237         u8                      peer_smc_release;
238         u8                      peer_hostname[SMC_MAX_HOSTNAME_LEN];
239         union {
240                 struct { /* SMC-R */
241                         enum smc_lgr_role       role;
242                                                 /* client or server */
243                         struct smc_link         lnk[SMC_LINKS_PER_LGR_MAX];
244                                                 /* smc link */
245                         char                    peer_systemid[SMC_SYSTEMID_LEN];
246                                                 /* unique system_id of peer */
247                         struct smc_rtoken       rtokens[SMC_RMBS_PER_LGR_MAX]
248                                                 [SMC_LINKS_PER_LGR_MAX];
249                                                 /* remote addr/key pairs */
250                         DECLARE_BITMAP(rtokens_used_mask, SMC_RMBS_PER_LGR_MAX);
251                                                 /* used rtoken elements */
252                         u8                      next_link_id;
253                         enum smc_lgr_type       type;
254                                                 /* redundancy state */
255                         u8                      pnet_id[SMC_MAX_PNETID_LEN + 1];
256                                                 /* pnet id of this lgr */
257                         struct list_head        llc_event_q;
258                                                 /* queue for llc events */
259                         spinlock_t              llc_event_q_lock;
260                                                 /* protects llc_event_q */
261                         struct mutex            llc_conf_mutex;
262                                                 /* protects lgr reconfig. */
263                         struct work_struct      llc_add_link_work;
264                         struct work_struct      llc_del_link_work;
265                         struct work_struct      llc_event_work;
266                                                 /* llc event worker */
267                         wait_queue_head_t       llc_flow_waiter;
268                                                 /* w4 next llc event */
269                         wait_queue_head_t       llc_msg_waiter;
270                                                 /* w4 next llc msg */
271                         struct smc_llc_flow     llc_flow_lcl;
272                                                 /* llc local control field */
273                         struct smc_llc_flow     llc_flow_rmt;
274                                                 /* llc remote control field */
275                         struct smc_llc_qentry   *delayed_event;
276                                                 /* arrived when flow active */
277                         spinlock_t              llc_flow_lock;
278                                                 /* protects llc flow */
279                         int                     llc_testlink_time;
280                                                 /* link keep alive time */
281                         u32                     llc_termination_rsn;
282                                                 /* rsn code for termination */
283                 };
284                 struct { /* SMC-D */
285                         u64                     peer_gid;
286                                                 /* Peer GID (remote) */
287                         struct smcd_dev         *smcd;
288                                                 /* ISM device for VLAN reg. */
289                         u8                      peer_shutdown : 1;
290                                                 /* peer triggered shutdownn */
291                 };
292         };
293 };
294
295 struct smc_clc_msg_local;
296
297 struct smc_init_info {
298         u8                      is_smcd;
299         u8                      smc_type_v1;
300         u8                      smc_type_v2;
301         u8                      first_contact_peer;
302         u8                      first_contact_local;
303         unsigned short          vlan_id;
304         /* SMC-R */
305         struct smc_clc_msg_local *ib_lcl;
306         struct smc_ib_device    *ib_dev;
307         u8                      ib_gid[SMC_GID_SIZE];
308         u8                      ib_port;
309         u32                     ib_clcqpn;
310         /* SMC-D */
311         u64                     ism_peer_gid[SMC_MAX_ISM_DEVS + 1];
312         struct smcd_dev         *ism_dev[SMC_MAX_ISM_DEVS + 1];
313         u16                     ism_chid[SMC_MAX_ISM_DEVS + 1];
314         u8                      ism_offered_cnt; /* # of ISM devices offered */
315         u8                      ism_selected;    /* index of selected ISM dev*/
316         u8                      smcd_version;
317 };
318
319 /* Find the connection associated with the given alert token in the link group.
320  * To use rbtrees we have to implement our own search core.
321  * Requires @conns_lock
322  * @token       alert token to search for
323  * @lgr          link group to search in
324  * Returns connection associated with token if found, NULL otherwise.
325  */
326 static inline struct smc_connection *smc_lgr_find_conn(
327         u32 token, struct smc_link_group *lgr)
328 {
329         struct smc_connection *res = NULL;
330         struct rb_node *node;
331
332         node = lgr->conns_all.rb_node;
333         while (node) {
334                 struct smc_connection *cur = rb_entry(node,
335                                         struct smc_connection, alert_node);
336
337                 if (cur->alert_token_local > token) {
338                         node = node->rb_left;
339                 } else {
340                         if (cur->alert_token_local < token) {
341                                 node = node->rb_right;
342                         } else {
343                                 res = cur;
344                                 break;
345                         }
346                 }
347         }
348
349         return res;
350 }
351
352 /* returns true if the specified link is usable */
353 static inline bool smc_link_usable(struct smc_link *lnk)
354 {
355         if (lnk->state == SMC_LNK_UNUSED || lnk->state == SMC_LNK_INACTIVE)
356                 return false;
357         return true;
358 }
359
360 static inline bool smc_link_active(struct smc_link *lnk)
361 {
362         return lnk->state == SMC_LNK_ACTIVE;
363 }
364
365 struct smc_sock;
366 struct smc_clc_msg_accept_confirm;
367 struct smc_clc_msg_local;
368
369 void smc_lgr_cleanup_early(struct smc_connection *conn);
370 void smc_lgr_terminate_sched(struct smc_link_group *lgr);
371 void smcr_port_add(struct smc_ib_device *smcibdev, u8 ibport);
372 void smcr_port_err(struct smc_ib_device *smcibdev, u8 ibport);
373 void smc_smcd_terminate(struct smcd_dev *dev, u64 peer_gid,
374                         unsigned short vlan);
375 void smc_smcd_terminate_all(struct smcd_dev *dev);
376 void smc_smcr_terminate_all(struct smc_ib_device *smcibdev);
377 int smc_buf_create(struct smc_sock *smc, bool is_smcd);
378 int smc_uncompress_bufsize(u8 compressed);
379 int smc_rmb_rtoken_handling(struct smc_connection *conn, struct smc_link *link,
380                             struct smc_clc_msg_accept_confirm *clc);
381 int smc_rtoken_add(struct smc_link *lnk, __be64 nw_vaddr, __be32 nw_rkey);
382 int smc_rtoken_delete(struct smc_link *lnk, __be32 nw_rkey);
383 void smc_rtoken_set(struct smc_link_group *lgr, int link_idx, int link_idx_new,
384                     __be32 nw_rkey_known, __be64 nw_vaddr, __be32 nw_rkey);
385 void smc_rtoken_set2(struct smc_link_group *lgr, int rtok_idx, int link_id,
386                      __be64 nw_vaddr, __be32 nw_rkey);
387 void smc_sndbuf_sync_sg_for_cpu(struct smc_connection *conn);
388 void smc_sndbuf_sync_sg_for_device(struct smc_connection *conn);
389 void smc_rmb_sync_sg_for_cpu(struct smc_connection *conn);
390 void smc_rmb_sync_sg_for_device(struct smc_connection *conn);
391 int smc_vlan_by_tcpsk(struct socket *clcsock, struct smc_init_info *ini);
392
393 void smc_conn_free(struct smc_connection *conn);
394 int smc_conn_create(struct smc_sock *smc, struct smc_init_info *ini);
395 void smc_lgr_schedule_free_work_fast(struct smc_link_group *lgr);
396 int smc_core_init(void);
397 void smc_core_exit(void);
398
399 int smcr_link_init(struct smc_link_group *lgr, struct smc_link *lnk,
400                    u8 link_idx, struct smc_init_info *ini);
401 void smcr_link_clear(struct smc_link *lnk, bool log);
402 int smcr_buf_map_lgr(struct smc_link *lnk);
403 int smcr_buf_reg_lgr(struct smc_link *lnk);
404 void smcr_lgr_set_type(struct smc_link_group *lgr, enum smc_lgr_type new_type);
405 void smcr_lgr_set_type_asym(struct smc_link_group *lgr,
406                             enum smc_lgr_type new_type, int asym_lnk_idx);
407 int smcr_link_reg_rmb(struct smc_link *link, struct smc_buf_desc *rmb_desc);
408 struct smc_link *smc_switch_conns(struct smc_link_group *lgr,
409                                   struct smc_link *from_lnk, bool is_dev_err);
410 void smcr_link_down_cond(struct smc_link *lnk);
411 void smcr_link_down_cond_sched(struct smc_link *lnk);
412
413 static inline struct smc_link_group *smc_get_lgr(struct smc_link *link)
414 {
415         return link->lgr;
416 }
417 #endif