1 /* SPDX-License-Identifier: GPL-2.0-or-later */
2 /*
3  * RDMA Transport Layer
4  *
5  * Copyright (c) 2014 - 2018 ProfitBricks GmbH. All rights reserved.
6  * Copyright (c) 2018 - 2019 1&1 IONOS Cloud GmbH. All rights reserved.
7  * Copyright (c) 2019 - 2020 1&1 IONOS SE. All rights reserved.
8  */
9 
10 #ifndef RTRS_PRI_H
11 #define RTRS_PRI_H
12 
13 #include <linux/uuid.h>
14 #include <rdma/rdma_cm.h>
15 #include <rdma/ib_verbs.h>
16 #include <rdma/ib.h>
17 
18 #include "rtrs.h"
19 
20 #define RTRS_PROTO_VER_MAJOR 2
21 #define RTRS_PROTO_VER_MINOR 0
22 
23 #define RTRS_PROTO_VER_STRING __stringify(RTRS_PROTO_VER_MAJOR) "." \
24 			       __stringify(RTRS_PROTO_VER_MINOR)
25 
26 enum rtrs_imm_const {
27 	MAX_IMM_TYPE_BITS = 4,
28 	MAX_IMM_TYPE_MASK = ((1 << MAX_IMM_TYPE_BITS) - 1),
29 	MAX_IMM_PAYL_BITS = 28,
30 	MAX_IMM_PAYL_MASK = ((1 << MAX_IMM_PAYL_BITS) - 1),
31 };
32 
33 enum rtrs_imm_type {
34 	RTRS_IO_REQ_IMM       = 0, /* client to server */
35 	RTRS_IO_RSP_IMM       = 1, /* server to client */
36 	RTRS_IO_RSP_W_INV_IMM = 2, /* server to client */
37 
38 	RTRS_HB_MSG_IMM = 8, /* HB: HeartBeat */
39 	RTRS_HB_ACK_IMM = 9,
40 
41 	RTRS_LAST_IMM,
42 };
43 
44 enum {
45 	SERVICE_CON_QUEUE_DEPTH = 512,
46 
47 	MAX_PATHS_NUM = 128,
48 
49 	/*
50 	 * With the size of struct rtrs_permit allocated on the client, 4K
51 	 * is the maximum number of rtrs_permits we can allocate. This number is
52 	 * also used on the client to allocate the IU for the user connection
53 	 * to receive the RDMA addresses from the server.
54 	 */
55 	MAX_SESS_QUEUE_DEPTH = 4096,
56 
57 	RTRS_HB_INTERVAL_MS = 5000,
58 	RTRS_HB_MISSED_MAX = 5,
59 
60 	RTRS_MAGIC = 0x1BBD,
61 	RTRS_PROTO_VER = (RTRS_PROTO_VER_MAJOR << 8) | RTRS_PROTO_VER_MINOR,
62 };
63 
64 struct rtrs_ib_dev;
65 
66 struct rtrs_rdma_dev_pd_ops {
67 	struct rtrs_ib_dev *(*alloc)(void);
68 	void (*free)(struct rtrs_ib_dev *dev);
69 	int (*init)(struct rtrs_ib_dev *dev);
70 	void (*deinit)(struct rtrs_ib_dev *dev);
71 };
72 
73 struct rtrs_rdma_dev_pd {
74 	struct mutex		mutex;
75 	struct list_head	list;
76 	enum ib_pd_flags	pd_flags;
77 	const struct rtrs_rdma_dev_pd_ops *ops;
78 };
79 
80 struct rtrs_ib_dev {
81 	struct ib_device	 *ib_dev;
82 	struct ib_pd		 *ib_pd;
83 	struct kref		 ref;
84 	struct list_head	 entry;
85 	struct rtrs_rdma_dev_pd *pool;
86 };
87 
88 struct rtrs_con {
89 	struct rtrs_sess	*sess;
90 	struct ib_qp		*qp;
91 	struct ib_cq		*cq;
92 	struct rdma_cm_id	*cm_id;
93 	unsigned int		cid;
94 };
95 
96 struct rtrs_sess {
97 	struct list_head	entry;
98 	struct sockaddr_storage dst_addr;
99 	struct sockaddr_storage src_addr;
100 	char			sessname[NAME_MAX];
101 	uuid_t			uuid;
102 	struct rtrs_con	**con;
103 	unsigned int		con_num;
104 	unsigned int		recon_cnt;
105 	struct rtrs_ib_dev	*dev;
106 	int			dev_ref;
107 	struct ib_cqe		*hb_cqe;
108 	void			(*hb_err_handler)(struct rtrs_con *con);
109 	struct workqueue_struct *hb_wq;
110 	struct delayed_work	hb_dwork;
111 	unsigned int		hb_interval_ms;
112 	unsigned int		hb_missed_cnt;
113 	unsigned int		hb_missed_max;
114 };
115 
116 /* rtrs information unit */
117 struct rtrs_iu {
118 	struct list_head        list;
119 	struct ib_cqe           cqe;
120 	dma_addr_t              dma_addr;
121 	void                    *buf;
122 	size_t                  size;
123 	enum dma_data_direction direction;
124 };
125 
126 /**
127  * enum rtrs_msg_types - RTRS message types, see also rtrs/README
128  * @RTRS_MSG_INFO_REQ:		Client additional info request to the server
129  * @RTRS_MSG_INFO_RSP:		Server additional info response to the client
130  * @RTRS_MSG_WRITE:		Client writes data per RDMA to server
131  * @RTRS_MSG_READ:		Client requests data transfer from server
132  * @RTRS_MSG_RKEY_RSP:		Server refreshed rkey for rbuf
133  */
134 enum rtrs_msg_types {
135 	RTRS_MSG_INFO_REQ,
136 	RTRS_MSG_INFO_RSP,
137 	RTRS_MSG_WRITE,
138 	RTRS_MSG_READ,
139 	RTRS_MSG_RKEY_RSP,
140 };
141 
142 /**
143  * enum rtrs_msg_flags - RTRS message flags.
144  * @RTRS_NEED_INVAL:	Send invalidation in response.
145  * @RTRS_MSG_NEW_RKEY_F: Send refreshed rkey in response.
146  */
147 enum rtrs_msg_flags {
148 	RTRS_MSG_NEED_INVAL_F = 1 << 0,
149 	RTRS_MSG_NEW_RKEY_F = 1 << 1,
150 };
151 
152 /**
153  * struct rtrs_sg_desc - RDMA-Buffer entry description
154  * @addr:	Address of RDMA destination buffer
155  * @key:	Authorization rkey to write to the buffer
156  * @len:	Size of the buffer
157  */
158 struct rtrs_sg_desc {
159 	__le64			addr;
160 	__le32			key;
161 	__le32			len;
162 };
163 
164 /**
165  * struct rtrs_msg_conn_req - Client connection request to the server
166  * @magic:	   RTRS magic
167  * @version:	   RTRS protocol version
168  * @cid:	   Current connection id
169  * @cid_num:	   Number of connections per session
170  * @recon_cnt:	   Reconnections counter
171  * @sess_uuid:	   UUID of a session (path)
172  * @paths_uuid:	   UUID of a group of sessions (paths)
173  *
174  * NOTE: max size 56 bytes, see man rdma_connect().
175  */
176 struct rtrs_msg_conn_req {
177 	/* Is set to 0 by cma.c in case of AF_IB, do not touch that.
178 	 * see https://www.spinics.net/lists/linux-rdma/msg22397.html
179 	 */
180 	u8		__cma_version;
181 	/* On sender side that should be set to 0, or cma_save_ip_info()
182 	 * extract garbage and will fail.
183 	 */
184 	u8		__ip_version;
185 	__le16		magic;
186 	__le16		version;
187 	__le16		cid;
188 	__le16		cid_num;
189 	__le16		recon_cnt;
190 	uuid_t		sess_uuid;
191 	uuid_t		paths_uuid;
192 	u8		reserved[12];
193 };
194 
195 /**
196  * struct rtrs_msg_conn_rsp - Server connection response to the client
197  * @magic:	   RTRS magic
198  * @version:	   RTRS protocol version
199  * @errno:	   If rdma_accept() then 0, if rdma_reject() indicates error
200  * @queue_depth:   max inflight messages (queue-depth) in this session
201  * @max_io_size:   max io size server supports
202  * @max_hdr_size:  max msg header size server supports
203  *
204  * NOTE: size is 56 bytes, max possible is 136 bytes, see man rdma_accept().
205  */
206 struct rtrs_msg_conn_rsp {
207 	__le16		magic;
208 	__le16		version;
209 	__le16		errno;
210 	__le16		queue_depth;
211 	__le32		max_io_size;
212 	__le32		max_hdr_size;
213 	__le32		flags;
214 	u8		reserved[36];
215 };
216 
217 /**
218  * struct rtrs_msg_info_req
219  * @type:		@RTRS_MSG_INFO_REQ
220  * @sessname:		Session name chosen by client
221  */
222 struct rtrs_msg_info_req {
223 	__le16		type;
224 	u8		sessname[NAME_MAX];
225 	u8		reserved[15];
226 };
227 
228 /**
229  * struct rtrs_msg_info_rsp
230  * @type:		@RTRS_MSG_INFO_RSP
231  * @sg_cnt:		Number of @desc entries
232  * @desc:		RDMA buffers where the client can write to server
233  */
234 struct rtrs_msg_info_rsp {
235 	__le16		type;
236 	__le16          sg_cnt;
237 	u8              reserved[4];
238 	struct rtrs_sg_desc desc[];
239 };
240 
241 /**
242  * struct rtrs_msg_rkey_rsp
243  * @type:		@RTRS_MSG_RKEY_RSP
244  * @buf_id:		RDMA buf_id of the new rkey
245  * @rkey:		new remote key for RDMA buffers id from server
246  */
247 struct rtrs_msg_rkey_rsp {
248 	__le16		type;
249 	__le16          buf_id;
250 	__le32		rkey;
251 };
252 
253 /**
254  * struct rtrs_msg_rdma_read - RDMA data transfer request from client
255  * @type:		always @RTRS_MSG_READ
256  * @usr_len:		length of user payload
257  * @sg_cnt:		number of @desc entries
258  * @desc:		RDMA buffers where the server can write the result to
259  */
260 struct rtrs_msg_rdma_read {
261 	__le16			type;
262 	__le16			usr_len;
263 	__le16			flags;
264 	__le16			sg_cnt;
265 	struct rtrs_sg_desc    desc[];
266 };
267 
268 /**
269  * struct_msg_rdma_write - Message transferred to server with RDMA-Write
270  * @type:		always @RTRS_MSG_WRITE
271  * @usr_len:		length of user payload
272  */
273 struct rtrs_msg_rdma_write {
274 	__le16			type;
275 	__le16			usr_len;
276 };
277 
278 /**
279  * struct_msg_rdma_hdr - header for read or write request
280  * @type:		@RTRS_MSG_WRITE | @RTRS_MSG_READ
281  */
282 struct rtrs_msg_rdma_hdr {
283 	__le16			type;
284 };
285 
286 /* rtrs.c */
287 
288 struct rtrs_iu *rtrs_iu_alloc(u32 queue_size, size_t size, gfp_t t,
289 			      struct ib_device *dev, enum dma_data_direction,
290 			      void (*done)(struct ib_cq *cq, struct ib_wc *wc));
291 void rtrs_iu_free(struct rtrs_iu *iu, enum dma_data_direction dir,
292 		  struct ib_device *dev, u32 queue_size);
293 int rtrs_iu_post_recv(struct rtrs_con *con, struct rtrs_iu *iu);
294 int rtrs_iu_post_send(struct rtrs_con *con, struct rtrs_iu *iu, size_t size,
295 		      struct ib_send_wr *head);
296 int rtrs_iu_post_rdma_write_imm(struct rtrs_con *con, struct rtrs_iu *iu,
297 				struct ib_sge *sge, unsigned int num_sge,
298 				u32 rkey, u64 rdma_addr, u32 imm_data,
299 				enum ib_send_flags flags,
300 				struct ib_send_wr *head);
301 
302 int rtrs_post_recv_empty(struct rtrs_con *con, struct ib_cqe *cqe);
303 int rtrs_post_rdma_write_imm_empty(struct rtrs_con *con, struct ib_cqe *cqe,
304 				   u32 imm_data, enum ib_send_flags flags,
305 				   struct ib_send_wr *head);
306 
307 int rtrs_cq_qp_create(struct rtrs_sess *rtrs_sess, struct rtrs_con *con,
308 		      u32 max_send_sge, int cq_vector, u16 cq_size,
309 		      u16 wr_queue_size, enum ib_poll_context poll_ctx);
310 void rtrs_cq_qp_destroy(struct rtrs_con *con);
311 
312 void rtrs_init_hb(struct rtrs_sess *sess, struct ib_cqe *cqe,
313 		  unsigned int interval_ms, unsigned int missed_max,
314 		  void (*err_handler)(struct rtrs_con *con),
315 		  struct workqueue_struct *wq);
316 void rtrs_start_hb(struct rtrs_sess *sess);
317 void rtrs_stop_hb(struct rtrs_sess *sess);
318 void rtrs_send_hb_ack(struct rtrs_sess *sess);
319 
320 void rtrs_rdma_dev_pd_init(enum ib_pd_flags pd_flags,
321 			   struct rtrs_rdma_dev_pd *pool);
322 void rtrs_rdma_dev_pd_deinit(struct rtrs_rdma_dev_pd *pool);
323 
324 struct rtrs_ib_dev *rtrs_ib_dev_find_or_add(struct ib_device *ib_dev,
325 					    struct rtrs_rdma_dev_pd *pool);
326 int rtrs_ib_dev_put(struct rtrs_ib_dev *dev);
327 
328 static inline u32 rtrs_to_imm(u32 type, u32 payload)
329 {
330 	BUILD_BUG_ON(MAX_IMM_PAYL_BITS + MAX_IMM_TYPE_BITS != 32);
331 	BUILD_BUG_ON(RTRS_LAST_IMM > (1<<MAX_IMM_TYPE_BITS));
332 	return ((type & MAX_IMM_TYPE_MASK) << MAX_IMM_PAYL_BITS) |
333 		(payload & MAX_IMM_PAYL_MASK);
334 }
335 
336 static inline void rtrs_from_imm(u32 imm, u32 *type, u32 *payload)
337 {
338 	*payload = imm & MAX_IMM_PAYL_MASK;
339 	*type = imm >> MAX_IMM_PAYL_BITS;
340 }
341 
342 static inline u32 rtrs_to_io_req_imm(u32 addr)
343 {
344 	return rtrs_to_imm(RTRS_IO_REQ_IMM, addr);
345 }
346 
347 static inline u32 rtrs_to_io_rsp_imm(u32 msg_id, int errno, bool w_inval)
348 {
349 	enum rtrs_imm_type type;
350 	u32 payload;
351 
352 	/* 9 bits for errno, 19 bits for msg_id */
353 	payload = (abs(errno) & 0x1ff) << 19 | (msg_id & 0x7ffff);
354 	type = w_inval ? RTRS_IO_RSP_W_INV_IMM : RTRS_IO_RSP_IMM;
355 
356 	return rtrs_to_imm(type, payload);
357 }
358 
359 static inline void rtrs_from_io_rsp_imm(u32 payload, u32 *msg_id, int *errno)
360 {
361 	/* 9 bits for errno, 19 bits for msg_id */
362 	*msg_id = payload & 0x7ffff;
363 	*errno = -(int)((payload >> 19) & 0x1ff);
364 }
365 
366 #define STAT_STORE_FUNC(type, set_value, reset)				\
367 static ssize_t set_value##_store(struct kobject *kobj,			\
368 			     struct kobj_attribute *attr,		\
369 			     const char *buf, size_t count)		\
370 {									\
371 	int ret = -EINVAL;						\
372 	type *stats = container_of(kobj, type, kobj_stats);		\
373 									\
374 	if (sysfs_streq(buf, "1"))					\
375 		ret = reset(stats, true);			\
376 	else if (sysfs_streq(buf, "0"))					\
377 		ret = reset(stats, false);			\
378 	if (ret)							\
379 		return ret;						\
380 									\
381 	return count;							\
382 }
383 
384 #define STAT_SHOW_FUNC(type, get_value, print)				\
385 static ssize_t get_value##_show(struct kobject *kobj,			\
386 			   struct kobj_attribute *attr,			\
387 			   char *page)					\
388 {									\
389 	type *stats = container_of(kobj, type, kobj_stats);		\
390 									\
391 	return print(stats, page, PAGE_SIZE);			\
392 }
393 
394 #define STAT_ATTR(type, stat, print, reset)				\
395 STAT_STORE_FUNC(type, stat, reset)					\
396 STAT_SHOW_FUNC(type, stat, print)					\
397 static struct kobj_attribute stat##_attr = __ATTR_RW(stat)
398 
399 #endif /* RTRS_PRI_H */
400