File: smbdirect.h

package info (click to toggle)
linux 4.19.37-3
  • links: PTS, VCS
  • area: main
  • in suites: bullseye, buster, sid
  • size: 962,264 kB
  • sloc: ansic: 16,757,120; asm: 271,404; makefile: 38,285; sh: 33,529; perl: 27,681; python: 21,031; cpp: 5,063; yacc: 4,648; lex: 2,585; awk: 1,385; ruby: 25; sed: 5
file content (338 lines) | stat: -rw-r--r-- 9,278 bytes parent folder | download | duplicates (7)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
/*
 *   Copyright (C) 2017, Microsoft Corporation.
 *
 *   Author(s): Long Li <longli@microsoft.com>
 *
 *   This program is free software;  you can redistribute it and/or modify
 *   it under the terms of the GNU General Public License as published by
 *   the Free Software Foundation; either version 2 of the License, or
 *   (at your option) any later version.
 *
 *   This program is distributed in the hope that it will be useful,
 *   but WITHOUT ANY WARRANTY;  without even the implied warranty of
 *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See
 *   the GNU General Public License for more details.
 */
#ifndef _SMBDIRECT_H
#define _SMBDIRECT_H

#ifdef CONFIG_CIFS_SMB_DIRECT
#define cifs_rdma_enabled(server)	((server)->rdma)

#include "cifsglob.h"
#include <rdma/ib_verbs.h>
#include <rdma/rdma_cm.h>
#include <linux/mempool.h>

extern int rdma_readwrite_threshold;
extern int smbd_max_frmr_depth;
extern int smbd_keep_alive_interval;
extern int smbd_max_receive_size;
extern int smbd_max_fragmented_recv_size;
extern int smbd_max_send_size;
extern int smbd_send_credit_target;
extern int smbd_receive_credit_max;

enum keep_alive_status {
	KEEP_ALIVE_NONE,
	KEEP_ALIVE_PENDING,
	KEEP_ALIVE_SENT,
};

enum smbd_connection_status {
	SMBD_CREATED,
	SMBD_CONNECTING,
	SMBD_CONNECTED,
	SMBD_NEGOTIATE_FAILED,
	SMBD_DISCONNECTING,
	SMBD_DISCONNECTED,
	SMBD_DESTROYED
};

/*
 * The context for the SMBDirect transport
 * Everything related to the transport is here. It has several logical parts
 * 1. RDMA related structures
 * 2. SMBDirect connection parameters
 * 3. Memory registrations
 * 4. Receive and reassembly queues for data receive path
 * 5. mempools for allocating packets
 */
struct smbd_connection {
	enum smbd_connection_status transport_status;

	/* RDMA related */
	struct rdma_cm_id *id;
	struct ib_qp_init_attr qp_attr;
	struct ib_pd *pd;
	struct ib_cq *send_cq, *recv_cq;
	struct ib_device_attr dev_attr;
	int ri_rc;
	struct completion ri_done;
	wait_queue_head_t conn_wait;
	wait_queue_head_t wait_destroy;

	struct completion negotiate_completion;
	bool negotiate_done;

	struct work_struct destroy_work;
	struct work_struct disconnect_work;
	struct work_struct recv_done_work;
	struct work_struct post_send_credits_work;

	spinlock_t lock_new_credits_offered;
	int new_credits_offered;

	/* Connection parameters defined in [MS-SMBD] 3.1.1.1 */
	int receive_credit_max;
	int send_credit_target;
	int max_send_size;
	int max_fragmented_recv_size;
	int max_fragmented_send_size;
	int max_receive_size;
	int keep_alive_interval;
	int max_readwrite_size;
	enum keep_alive_status keep_alive_requested;
	int protocol;
	atomic_t send_credits;
	atomic_t receive_credits;
	int receive_credit_target;
	int fragment_reassembly_remaining;

	/* Memory registrations */
	/* Maximum number of RDMA read/write outstanding on this connection */
	int responder_resources;
	/* Maximum number of SGEs in a RDMA write/read */
	int max_frmr_depth;
	/*
	 * If payload is less than or equal to the threshold,
	 * use RDMA send/recv to send upper layer I/O.
	 * If payload is more than the threshold,
	 * use RDMA read/write through memory registration for I/O.
	 */
	int rdma_readwrite_threshold;
	enum ib_mr_type mr_type;
	struct list_head mr_list;
	spinlock_t mr_list_lock;
	/* The number of available MRs ready for memory registration */
	atomic_t mr_ready_count;
	atomic_t mr_used_count;
	wait_queue_head_t wait_mr;
	struct work_struct mr_recovery_work;
	/* Used by transport to wait until all MRs are returned */
	wait_queue_head_t wait_for_mr_cleanup;

	/* Activity accoutning */
	/* Pending reqeusts issued from upper layer */
	int smbd_send_pending;
	wait_queue_head_t wait_smbd_send_pending;

	int smbd_recv_pending;
	wait_queue_head_t wait_smbd_recv_pending;

	atomic_t send_pending;
	wait_queue_head_t wait_send_pending;
	atomic_t send_payload_pending;
	wait_queue_head_t wait_send_payload_pending;

	/* Receive queue */
	struct list_head receive_queue;
	int count_receive_queue;
	spinlock_t receive_queue_lock;

	struct list_head empty_packet_queue;
	int count_empty_packet_queue;
	spinlock_t empty_packet_queue_lock;

	wait_queue_head_t wait_receive_queues;

	/* Reassembly queue */
	struct list_head reassembly_queue;
	spinlock_t reassembly_queue_lock;
	wait_queue_head_t wait_reassembly_queue;

	/* total data length of reassembly queue */
	int reassembly_data_length;
	int reassembly_queue_length;
	/* the offset to first buffer in reassembly queue */
	int first_entry_offset;

	bool send_immediate;

	wait_queue_head_t wait_send_queue;

	/*
	 * Indicate if we have received a full packet on the connection
	 * This is used to identify the first SMBD packet of a assembled
	 * payload (SMB packet) in reassembly queue so we can return a
	 * RFC1002 length to upper layer to indicate the length of the SMB
	 * packet received
	 */
	bool full_packet_received;

	struct workqueue_struct *workqueue;
	struct delayed_work idle_timer_work;
	struct delayed_work send_immediate_work;

	/* Memory pool for preallocating buffers */
	/* request pool for RDMA send */
	struct kmem_cache *request_cache;
	mempool_t *request_mempool;

	/* response pool for RDMA receive */
	struct kmem_cache *response_cache;
	mempool_t *response_mempool;

	/* for debug purposes */
	unsigned int count_get_receive_buffer;
	unsigned int count_put_receive_buffer;
	unsigned int count_reassembly_queue;
	unsigned int count_enqueue_reassembly_queue;
	unsigned int count_dequeue_reassembly_queue;
	unsigned int count_send_empty;
};

enum smbd_message_type {
	SMBD_NEGOTIATE_RESP,
	SMBD_TRANSFER_DATA,
};

#define SMB_DIRECT_RESPONSE_REQUESTED 0x0001

/* SMBD negotiation request packet [MS-SMBD] 2.2.1 */
struct smbd_negotiate_req {
	__le16 min_version;
	__le16 max_version;
	__le16 reserved;
	__le16 credits_requested;
	__le32 preferred_send_size;
	__le32 max_receive_size;
	__le32 max_fragmented_size;
} __packed;

/* SMBD negotiation response packet [MS-SMBD] 2.2.2 */
struct smbd_negotiate_resp {
	__le16 min_version;
	__le16 max_version;
	__le16 negotiated_version;
	__le16 reserved;
	__le16 credits_requested;
	__le16 credits_granted;
	__le32 status;
	__le32 max_readwrite_size;
	__le32 preferred_send_size;
	__le32 max_receive_size;
	__le32 max_fragmented_size;
} __packed;

/* SMBD data transfer packet with payload [MS-SMBD] 2.2.3 */
struct smbd_data_transfer {
	__le16 credits_requested;
	__le16 credits_granted;
	__le16 flags;
	__le16 reserved;
	__le32 remaining_data_length;
	__le32 data_offset;
	__le32 data_length;
	__le32 padding;
	__u8 buffer[];
} __packed;

/* The packet fields for a registered RDMA buffer */
struct smbd_buffer_descriptor_v1 {
	__le64 offset;
	__le32 token;
	__le32 length;
} __packed;

/* Default maximum number of SGEs in a RDMA send/recv */
#define SMBDIRECT_MAX_SGE	16
/* The context for a SMBD request */
struct smbd_request {
	struct smbd_connection *info;
	struct ib_cqe cqe;

	/* true if this request carries upper layer payload */
	bool has_payload;

	/* the SGE entries for this packet */
	struct ib_sge sge[SMBDIRECT_MAX_SGE];
	int num_sge;

	/* SMBD packet header follows this structure */
	u8 packet[];
};

/* The context for a SMBD response */
struct smbd_response {
	struct smbd_connection *info;
	struct ib_cqe cqe;
	struct ib_sge sge;

	enum smbd_message_type type;

	/* Link to receive queue or reassembly queue */
	struct list_head list;

	/* Indicate if this is the 1st packet of a payload */
	bool first_segment;

	/* SMBD packet header and payload follows this structure */
	u8 packet[];
};

/* Create a SMBDirect session */
struct smbd_connection *smbd_get_connection(
	struct TCP_Server_Info *server, struct sockaddr *dstaddr);

/* Reconnect SMBDirect session */
int smbd_reconnect(struct TCP_Server_Info *server);
/* Destroy SMBDirect session */
void smbd_destroy(struct smbd_connection *info);

/* Interface for carrying upper layer I/O through send/recv */
int smbd_recv(struct smbd_connection *info, struct msghdr *msg);
int smbd_send(struct TCP_Server_Info *server, struct smb_rqst *rqst);

enum mr_state {
	MR_READY,
	MR_REGISTERED,
	MR_INVALIDATED,
	MR_ERROR
};

struct smbd_mr {
	struct smbd_connection	*conn;
	struct list_head	list;
	enum mr_state		state;
	struct ib_mr		*mr;
	struct scatterlist	*sgl;
	int			sgl_count;
	enum dma_data_direction	dir;
	union {
		struct ib_reg_wr	wr;
		struct ib_send_wr	inv_wr;
	};
	struct ib_cqe		cqe;
	bool			need_invalidate;
	struct completion	invalidate_done;
};

/* Interfaces to register and deregister MR for RDMA read/write */
struct smbd_mr *smbd_register_mr(
	struct smbd_connection *info, struct page *pages[], int num_pages,
	int offset, int tailsz, bool writing, bool need_invalidate);
int smbd_deregister_mr(struct smbd_mr *mr);

#else
#define cifs_rdma_enabled(server)	0
struct smbd_connection {};
static inline void *smbd_get_connection(
	struct TCP_Server_Info *server, struct sockaddr *dstaddr) {return NULL;}
static inline int smbd_reconnect(struct TCP_Server_Info *server) {return -1; }
static inline void smbd_destroy(struct smbd_connection *info) {}
static inline int smbd_recv(struct smbd_connection *info, struct msghdr *msg) {return -1; }
static inline int smbd_send(struct TCP_Server_Info *server, struct smb_rqst *rqst) {return -1; }
#endif

#endif