1 /* SPDX-License-Identifier: GPL-2.0-or-later */
2 /*
3 * Copyright (C) 2017, Microsoft Corporation.
4 *
5 * Author(s): Long Li <longli@microsoft.com>
6 */
7 #ifndef _SMBDIRECT_H
8 #define _SMBDIRECT_H
9
10 #ifdef CONFIG_CIFS_SMB_DIRECT
11 #define cifs_rdma_enabled(server) ((server)->rdma)
12
13 #include "cifsglob.h"
14 #include <rdma/ib_verbs.h>
15 #include <rdma/rdma_cm.h>
16 #include <linux/mempool.h>
17
18 extern int rdma_readwrite_threshold;
19 extern int smbd_max_frmr_depth;
20 extern int smbd_keep_alive_interval;
21 extern int smbd_max_receive_size;
22 extern int smbd_max_fragmented_recv_size;
23 extern int smbd_max_send_size;
24 extern int smbd_send_credit_target;
25 extern int smbd_receive_credit_max;
26
27 enum keep_alive_status {
28 KEEP_ALIVE_NONE,
29 KEEP_ALIVE_PENDING,
30 KEEP_ALIVE_SENT,
31 };
32
33 enum smbd_connection_status {
34 SMBD_CREATED,
35 SMBD_CONNECTING,
36 SMBD_CONNECTED,
37 SMBD_NEGOTIATE_FAILED,
38 SMBD_DISCONNECTING,
39 SMBD_DISCONNECTED,
40 SMBD_DESTROYED
41 };
42
43 /*
44 * The context for the SMBDirect transport
45 * Everything related to the transport is here. It has several logical parts
46 * 1. RDMA related structures
47 * 2. SMBDirect connection parameters
48 * 3. Memory registrations
49 * 4. Receive and reassembly queues for data receive path
50 * 5. mempools for allocating packets
51 */
52 struct smbd_connection {
53 enum smbd_connection_status transport_status;
54
55 /* RDMA related */
56 struct rdma_cm_id *id;
57 struct ib_qp_init_attr qp_attr;
58 struct ib_pd *pd;
59 struct ib_cq *send_cq, *recv_cq;
60 struct ib_device_attr dev_attr;
61 int ri_rc;
62 struct completion ri_done;
63 wait_queue_head_t conn_wait;
64 wait_queue_head_t disconn_wait;
65
66 struct completion negotiate_completion;
67 bool negotiate_done;
68
69 struct work_struct disconnect_work;
70 struct work_struct post_send_credits_work;
71
72 spinlock_t lock_new_credits_offered;
73 int new_credits_offered;
74
75 /* Connection parameters defined in [MS-SMBD] 3.1.1.1 */
76 int receive_credit_max;
77 int send_credit_target;
78 int max_send_size;
79 int max_fragmented_recv_size;
80 int max_fragmented_send_size;
81 int max_receive_size;
82 int keep_alive_interval;
83 int max_readwrite_size;
84 enum keep_alive_status keep_alive_requested;
85 int protocol;
86 atomic_t send_credits;
87 atomic_t receive_credits;
88 int receive_credit_target;
89 int fragment_reassembly_remaining;
90
91 /* Memory registrations */
92 /* Maximum number of RDMA read/write outstanding on this connection */
93 int responder_resources;
94 /* Maximum number of pages in a single RDMA write/read on this connection */
95 int max_frmr_depth;
96 /*
97 * If payload is less than or equal to the threshold,
98 * use RDMA send/recv to send upper layer I/O.
99 * If payload is more than the threshold,
100 * use RDMA read/write through memory registration for I/O.
101 */
102 int rdma_readwrite_threshold;
103 enum ib_mr_type mr_type;
104 struct list_head mr_list;
105 spinlock_t mr_list_lock;
106 /* The number of available MRs ready for memory registration */
107 atomic_t mr_ready_count;
108 atomic_t mr_used_count;
109 wait_queue_head_t wait_mr;
110 struct work_struct mr_recovery_work;
111 /* Used by transport to wait until all MRs are returned */
112 wait_queue_head_t wait_for_mr_cleanup;
113
114 /* Activity accoutning */
115 atomic_t send_pending;
116 wait_queue_head_t wait_send_pending;
117 wait_queue_head_t wait_post_send;
118
119 /* Receive queue */
120 struct list_head receive_queue;
121 int count_receive_queue;
122 spinlock_t receive_queue_lock;
123
124 struct list_head empty_packet_queue;
125 int count_empty_packet_queue;
126 spinlock_t empty_packet_queue_lock;
127
128 wait_queue_head_t wait_receive_queues;
129
130 /* Reassembly queue */
131 struct list_head reassembly_queue;
132 spinlock_t reassembly_queue_lock;
133 wait_queue_head_t wait_reassembly_queue;
134
135 /* total data length of reassembly queue */
136 int reassembly_data_length;
137 int reassembly_queue_length;
138 /* the offset to first buffer in reassembly queue */
139 int first_entry_offset;
140
141 bool send_immediate;
142
143 wait_queue_head_t wait_send_queue;
144
145 /*
146 * Indicate if we have received a full packet on the connection
147 * This is used to identify the first SMBD packet of a assembled
148 * payload (SMB packet) in reassembly queue so we can return a
149 * RFC1002 length to upper layer to indicate the length of the SMB
150 * packet received
151 */
152 bool full_packet_received;
153
154 struct workqueue_struct *workqueue;
155 struct delayed_work idle_timer_work;
156
157 /* Memory pool for preallocating buffers */
158 /* request pool for RDMA send */
159 struct kmem_cache *request_cache;
160 mempool_t *request_mempool;
161
162 /* response pool for RDMA receive */
163 struct kmem_cache *response_cache;
164 mempool_t *response_mempool;
165
166 /* for debug purposes */
167 unsigned int count_get_receive_buffer;
168 unsigned int count_put_receive_buffer;
169 unsigned int count_reassembly_queue;
170 unsigned int count_enqueue_reassembly_queue;
171 unsigned int count_dequeue_reassembly_queue;
172 unsigned int count_send_empty;
173 };
174
175 enum smbd_message_type {
176 SMBD_NEGOTIATE_RESP,
177 SMBD_TRANSFER_DATA,
178 };
179
180 #define SMB_DIRECT_RESPONSE_REQUESTED 0x0001
181
182 /* SMBD negotiation request packet [MS-SMBD] 2.2.1 */
183 struct smbd_negotiate_req {
184 __le16 min_version;
185 __le16 max_version;
186 __le16 reserved;
187 __le16 credits_requested;
188 __le32 preferred_send_size;
189 __le32 max_receive_size;
190 __le32 max_fragmented_size;
191 } __packed;
192
193 /* SMBD negotiation response packet [MS-SMBD] 2.2.2 */
194 struct smbd_negotiate_resp {
195 __le16 min_version;
196 __le16 max_version;
197 __le16 negotiated_version;
198 __le16 reserved;
199 __le16 credits_requested;
200 __le16 credits_granted;
201 __le32 status;
202 __le32 max_readwrite_size;
203 __le32 preferred_send_size;
204 __le32 max_receive_size;
205 __le32 max_fragmented_size;
206 } __packed;
207
208 /* SMBD data transfer packet with payload [MS-SMBD] 2.2.3 */
209 struct smbd_data_transfer {
210 __le16 credits_requested;
211 __le16 credits_granted;
212 __le16 flags;
213 __le16 reserved;
214 __le32 remaining_data_length;
215 __le32 data_offset;
216 __le32 data_length;
217 __le32 padding;
218 __u8 buffer[];
219 } __packed;
220
221 /* The packet fields for a registered RDMA buffer */
222 struct smbd_buffer_descriptor_v1 {
223 __le64 offset;
224 __le32 token;
225 __le32 length;
226 } __packed;
227
228 /* Maximum number of SGEs used by smbdirect.c in any send work request */
229 #define SMBDIRECT_MAX_SEND_SGE 6
230
231 /* The context for a SMBD request */
232 struct smbd_request {
233 struct smbd_connection *info;
234 struct ib_cqe cqe;
235
236 /* the SGE entries for this work request */
237 struct ib_sge sge[SMBDIRECT_MAX_SEND_SGE];
238 int num_sge;
239
240 /* SMBD packet header follows this structure */
241 u8 packet[];
242 };
243
244 /* Maximum number of SGEs used by smbdirect.c in any receive work request */
245 #define SMBDIRECT_MAX_RECV_SGE 1
246
247 /* The context for a SMBD response */
248 struct smbd_response {
249 struct smbd_connection *info;
250 struct ib_cqe cqe;
251 struct ib_sge sge;
252
253 enum smbd_message_type type;
254
255 /* Link to receive queue or reassembly queue */
256 struct list_head list;
257
258 /* Indicate if this is the 1st packet of a payload */
259 bool first_segment;
260
261 /* SMBD packet header and payload follows this structure */
262 u8 packet[];
263 };
264
265 /* Create a SMBDirect session */
266 struct smbd_connection *smbd_get_connection(
267 struct TCP_Server_Info *server, struct sockaddr *dstaddr);
268
269 /* Reconnect SMBDirect session */
270 int smbd_reconnect(struct TCP_Server_Info *server);
271 /* Destroy SMBDirect session */
272 void smbd_destroy(struct TCP_Server_Info *server);
273
274 /* Interface for carrying upper layer I/O through send/recv */
275 int smbd_recv(struct smbd_connection *info, struct msghdr *msg);
276 int smbd_send(struct TCP_Server_Info *server,
277 int num_rqst, struct smb_rqst *rqst);
278
279 enum mr_state {
280 MR_READY,
281 MR_REGISTERED,
282 MR_INVALIDATED,
283 MR_ERROR
284 };
285
286 struct smbd_mr {
287 struct smbd_connection *conn;
288 struct list_head list;
289 enum mr_state state;
290 struct ib_mr *mr;
291 struct sg_table sgt;
292 enum dma_data_direction dir;
293 union {
294 struct ib_reg_wr wr;
295 struct ib_send_wr inv_wr;
296 };
297 struct ib_cqe cqe;
298 bool need_invalidate;
299 struct completion invalidate_done;
300 };
301
302 /* Interfaces to register and deregister MR for RDMA read/write */
303 struct smbd_mr *smbd_register_mr(
304 struct smbd_connection *info, struct iov_iter *iter,
305 bool writing, bool need_invalidate);
306 int smbd_deregister_mr(struct smbd_mr *mr);
307
308 #else
309 #define cifs_rdma_enabled(server) 0
310 struct smbd_connection {};
311 static inline void *smbd_get_connection(
312 struct TCP_Server_Info *server, struct sockaddr *dstaddr) {return NULL;}
313 static inline int smbd_reconnect(struct TCP_Server_Info *server) {return -1; }
314 static inline void smbd_destroy(struct TCP_Server_Info *server) {}
315 static inline int smbd_recv(struct smbd_connection *info, struct msghdr *msg) {return -1; }
316 static inline int smbd_send(struct TCP_Server_Info *server, int num_rqst, struct smb_rqst *rqst) {return -1; }
317 #endif
318
319 #endif
320
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