1 /*
2 * Copyright (c) 2006 - 2009 Mellanox Technology Inc. All rights reserved.
3 * Copyright (C) 2009 - 2010 Bart Van Assche <bvanassche@acm.org>.
4 *
5 * This software is available to you under a choice of one of two
6 * licenses. You may choose to be licensed under the terms of the GNU
7 * General Public License (GPL) Version 2, available from the file
8 * COPYING in the main directory of this source tree, or the
9 * OpenIB.org BSD license below:
10 *
11 * Redistribution and use in source and binary forms, with or
12 * without modification, are permitted provided that the following
13 * conditions are met:
14 *
15 * - Redistributions of source code must retain the above
16 * copyright notice, this list of conditions and the following
17 * disclaimer.
18 *
19 * - Redistributions in binary form must reproduce the above
20 * copyright notice, this list of conditions and the following
21 * disclaimer in the documentation and/or other materials
22 * provided with the distribution.
23 *
24 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
25 * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
26 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
27 * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
28 * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
29 * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
30 * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
31 * SOFTWARE.
32 *
33 */
34
35 #ifndef IB_SRPT_H
36 #define IB_SRPT_H
37
38 #include <linux/types.h>
39 #include <linux/list.h>
40 #include <linux/wait.h>
41
42 #include <rdma/ib_verbs.h>
43 #include <rdma/ib_sa.h>
44 #include <rdma/ib_cm.h>
45 #include <rdma/rdma_cm.h>
46 #include <rdma/rw.h>
47
48 #include <scsi/srp.h>
49
50 #include "ib_dm_mad.h"
51
52 /*
53 * The prefix the ServiceName field must start with in the device management
54 * ServiceEntries attribute pair. See also the SRP specification.
55 */
56 #define SRP_SERVICE_NAME_PREFIX "SRP.T10:"
57
58 struct srpt_nexus;
59
60 enum {
61 /*
62 * SRP IOControllerProfile attributes for SRP target ports that have
63 * not been defined in <scsi/srp.h>. Source: section B.7, table B.7
64 * in the SRP specification.
65 */
66 SRP_PROTOCOL = 0x0108,
67 SRP_PROTOCOL_VERSION = 0x0001,
68 SRP_IO_SUBCLASS = 0x609e,
69 SRP_SEND_TO_IOC = 0x01,
70 SRP_SEND_FROM_IOC = 0x02,
71 SRP_RDMA_READ_FROM_IOC = 0x08,
72 SRP_RDMA_WRITE_FROM_IOC = 0x20,
73
74 /*
75 * srp_login_cmd.req_flags bitmasks. See also table 9 in the SRP
76 * specification.
77 */
78 SRP_MTCH_ACTION = 0x03, /* MULTI-CHANNEL ACTION */
79 SRP_LOSOLNT = 0x10, /* logout solicited notification */
80 SRP_CRSOLNT = 0x20, /* credit request solicited notification */
81 SRP_AESOLNT = 0x40, /* asynchronous event solicited notification */
82
83 /*
84 * srp_cmd.sol_nt / srp_tsk_mgmt.sol_not bitmasks. See also tables
85 * 18 and 20 in the SRP specification.
86 */
87 SRP_SCSOLNT = 0x02, /* SCSOLNT = successful solicited notification */
88 SRP_UCSOLNT = 0x04, /* UCSOLNT = unsuccessful solicited notification */
89
90 /*
91 * srp_rsp.sol_not / srp_t_logout.sol_not bitmasks. See also tables
92 * 16 and 22 in the SRP specification.
93 */
94 SRP_SOLNT = 0x01, /* SOLNT = solicited notification */
95
96 /* See also table 24 in the SRP specification. */
97 SRP_TSK_MGMT_SUCCESS = 0x00,
98 SRP_TSK_MGMT_FUNC_NOT_SUPP = 0x04,
99 SRP_TSK_MGMT_FAILED = 0x05,
100
101 /* See also table 21 in the SRP specification. */
102 SRP_CMD_SIMPLE_Q = 0x0,
103 SRP_CMD_HEAD_OF_Q = 0x1,
104 SRP_CMD_ORDERED_Q = 0x2,
105 SRP_CMD_ACA = 0x4,
106
107 SRPT_DEF_SG_TABLESIZE = 128,
108 /*
109 * An experimentally determined value that avoids that QP creation
110 * fails due to "swiotlb buffer is full" on systems using the swiotlb.
111 */
112 SRPT_MAX_SG_PER_WQE = 16,
113
114 MIN_SRPT_SQ_SIZE = 16,
115 DEF_SRPT_SQ_SIZE = 4096,
116 MAX_SRPT_RQ_SIZE = 128,
117 MIN_SRPT_SRQ_SIZE = 4,
118 DEFAULT_SRPT_SRQ_SIZE = 4095,
119 MAX_SRPT_SRQ_SIZE = 65535,
120 MAX_SRPT_RDMA_SIZE = 1U << 24,
121 MAX_SRPT_RSP_SIZE = 1024,
122
123 SRP_MAX_ADD_CDB_LEN = 16,
124 SRP_MAX_IMM_DATA_OFFSET = 80,
125 SRP_MAX_IMM_DATA = 8 * 1024,
126 MIN_MAX_REQ_SIZE = 996,
127 DEFAULT_MAX_REQ_SIZE_1 = sizeof(struct srp_cmd)/*48*/ +
128 SRP_MAX_ADD_CDB_LEN +
129 sizeof(struct srp_indirect_buf)/*20*/ +
130 128 * sizeof(struct srp_direct_buf)/*16*/,
131 DEFAULT_MAX_REQ_SIZE_2 = SRP_MAX_IMM_DATA_OFFSET +
132 sizeof(struct srp_imm_buf) + SRP_MAX_IMM_DATA,
133 DEFAULT_MAX_REQ_SIZE = DEFAULT_MAX_REQ_SIZE_1 > DEFAULT_MAX_REQ_SIZE_2 ?
134 DEFAULT_MAX_REQ_SIZE_1 : DEFAULT_MAX_REQ_SIZE_2,
135
136 MIN_MAX_RSP_SIZE = sizeof(struct srp_rsp)/*36*/ + 4,
137 DEFAULT_MAX_RSP_SIZE = 256, /* leaves 220 bytes for sense data */
138
139 DEFAULT_MAX_RDMA_SIZE = 65536,
140 };
141
142 /**
143 * enum srpt_command_state - SCSI command state managed by SRPT
144 * @SRPT_STATE_NEW: New command arrived and is being processed.
145 * @SRPT_STATE_NEED_DATA: Processing a write or bidir command and waiting
146 * for data arrival.
147 * @SRPT_STATE_DATA_IN: Data for the write or bidir command arrived and is
148 * being processed.
149 * @SRPT_STATE_CMD_RSP_SENT: SRP_RSP for SRP_CMD has been sent.
150 * @SRPT_STATE_MGMT: Processing a SCSI task management command.
151 * @SRPT_STATE_MGMT_RSP_SENT: SRP_RSP for SRP_TSK_MGMT has been sent.
152 * @SRPT_STATE_DONE: Command processing finished successfully, command
153 * processing has been aborted or command processing
154 * failed.
155 */
156 enum srpt_command_state {
157 SRPT_STATE_NEW = 0,
158 SRPT_STATE_NEED_DATA = 1,
159 SRPT_STATE_DATA_IN = 2,
160 SRPT_STATE_CMD_RSP_SENT = 3,
161 SRPT_STATE_MGMT = 4,
162 SRPT_STATE_MGMT_RSP_SENT = 5,
163 SRPT_STATE_DONE = 6,
164 };
165
166 /**
167 * struct srpt_ioctx - shared SRPT I/O context information
168 * @cqe: Completion queue element.
169 * @buf: Pointer to the buffer.
170 * @dma: DMA address of the buffer.
171 * @offset: Offset of the first byte in @buf and @dma that is actually used.
172 * @index: Index of the I/O context in its ioctx_ring array.
173 */
174 struct srpt_ioctx {
175 struct ib_cqe cqe;
176 void *buf;
177 dma_addr_t dma;
178 uint32_t offset;
179 uint32_t index;
180 };
181
182 /**
183 * struct srpt_recv_ioctx - SRPT receive I/O context
184 * @ioctx: See above.
185 * @wait_list: Node for insertion in srpt_rdma_ch.cmd_wait_list.
186 * @byte_len: Number of bytes in @ioctx.buf.
187 */
188 struct srpt_recv_ioctx {
189 struct srpt_ioctx ioctx;
190 struct list_head wait_list;
191 int byte_len;
192 };
193
194 struct srpt_rw_ctx {
195 struct rdma_rw_ctx rw;
196 struct scatterlist *sg;
197 unsigned int nents;
198 };
199
200 /**
201 * struct srpt_send_ioctx - SRPT send I/O context
202 * @ioctx: See above.
203 * @ch: Channel pointer.
204 * @recv_ioctx: Receive I/O context associated with this send I/O context.
205 * Only used for processing immediate data.
206 * @s_rw_ctx: @rw_ctxs points here if only a single rw_ctx is needed.
207 * @rw_ctxs: RDMA read/write contexts.
208 * @imm_sg: Scatterlist for immediate data.
209 * @rdma_cqe: RDMA completion queue element.
210 * @state: I/O context state.
211 * @cmd: Target core command data structure.
212 * @sense_data: SCSI sense data.
213 * @n_rdma: Number of work requests needed to transfer this ioctx.
214 * @n_rw_ctx: Size of rw_ctxs array.
215 * @queue_status_only: Send a SCSI status back to the initiator but no data.
216 * @sense_data: Sense data to be sent to the initiator.
217 */
218 struct srpt_send_ioctx {
219 struct srpt_ioctx ioctx;
220 struct srpt_rdma_ch *ch;
221 struct srpt_recv_ioctx *recv_ioctx;
222
223 struct srpt_rw_ctx s_rw_ctx;
224 struct srpt_rw_ctx *rw_ctxs;
225
226 struct scatterlist imm_sg;
227
228 struct ib_cqe rdma_cqe;
229 enum srpt_command_state state;
230 struct se_cmd cmd;
231 u8 n_rdma;
232 u8 n_rw_ctx;
233 bool queue_status_only;
234 u8 sense_data[TRANSPORT_SENSE_BUFFER];
235 };
236
237 /**
238 * enum rdma_ch_state - SRP channel state
239 * @CH_CONNECTING: QP is in RTR state; waiting for RTU.
240 * @CH_LIVE: QP is in RTS state.
241 * @CH_DISCONNECTING: DREQ has been sent and waiting for DREP or DREQ has
242 * been received.
243 * @CH_DRAINING: DREP has been received or waiting for DREP timed out
244 * and last work request has been queued.
245 * @CH_DISCONNECTED: Last completion has been received.
246 */
247 enum rdma_ch_state {
248 CH_CONNECTING,
249 CH_LIVE,
250 CH_DISCONNECTING,
251 CH_DRAINING,
252 CH_DISCONNECTED,
253 };
254
255 /**
256 * struct srpt_rdma_ch - RDMA channel
257 * @nexus: I_T nexus this channel is associated with.
258 * @qp: IB queue pair used for communicating over this channel.
259 * @ib_cm: See below.
260 * @ib_cm.cm_id: IB CM ID associated with the channel.
261 * @rdma_cm: See below.
262 * @rdma_cm.cm_id: RDMA CM ID associated with the channel.
263 * @cq: IB completion queue for this channel.
264 * @zw_cqe: Zero-length write CQE.
265 * @rcu: RCU head.
266 * @kref: kref for this channel.
267 * @rq_size: IB receive queue size.
268 * @max_rsp_size: Maximum size of an RSP response message in bytes.
269 * @sq_wr_avail: number of work requests available in the send queue.
270 * @sport: pointer to the information of the HCA port used by this
271 * channel.
272 * @max_ti_iu_len: maximum target-to-initiator information unit length.
273 * @req_lim: request limit: maximum number of requests that may be sent
274 * by the initiator without having received a response.
275 * @req_lim_delta: Number of credits not yet sent back to the initiator.
276 * @imm_data_offset: Offset from start of SRP_CMD for immediate data.
277 * @spinlock: Protects free_list and state.
278 * @state: channel state. See also enum rdma_ch_state.
279 * @using_rdma_cm: Whether the RDMA/CM or IB/CM is used for this channel.
280 * @processing_wait_list: Whether or not cmd_wait_list is being processed.
281 * @rsp_buf_cache: kmem_cache for @ioctx_ring.
282 * @ioctx_ring: Send ring.
283 * @req_buf_cache: kmem_cache for @ioctx_recv_ring.
284 * @ioctx_recv_ring: Receive I/O context ring.
285 * @list: Node in srpt_nexus.ch_list.
286 * @cmd_wait_list: List of SCSI commands that arrived before the RTU event. This
287 * list contains struct srpt_ioctx elements and is protected
288 * against concurrent modification by the cm_id spinlock.
289 * @pkey: P_Key of the IB partition for this SRP channel.
290 * @sess: Session information associated with this SRP channel.
291 * @sess_name: Session name.
292 * @release_work: Allows scheduling of srpt_release_channel().
293 */
294 struct srpt_rdma_ch {
295 struct srpt_nexus *nexus;
296 struct ib_qp *qp;
297 union {
298 struct {
299 struct ib_cm_id *cm_id;
300 } ib_cm;
301 struct {
302 struct rdma_cm_id *cm_id;
303 } rdma_cm;
304 };
305 struct ib_cq *cq;
306 struct ib_cqe zw_cqe;
307 struct rcu_head rcu;
308 struct kref kref;
309 int rq_size;
310 u32 max_rsp_size;
311 atomic_t sq_wr_avail;
312 struct srpt_port *sport;
313 int max_ti_iu_len;
314 atomic_t req_lim;
315 atomic_t req_lim_delta;
316 u16 imm_data_offset;
317 spinlock_t spinlock;
318 enum rdma_ch_state state;
319 struct kmem_cache *rsp_buf_cache;
320 struct srpt_send_ioctx **ioctx_ring;
321 struct kmem_cache *req_buf_cache;
322 struct srpt_recv_ioctx **ioctx_recv_ring;
323 struct list_head list;
324 struct list_head cmd_wait_list;
325 uint16_t pkey;
326 bool using_rdma_cm;
327 bool processing_wait_list;
328 struct se_session *sess;
329 u8 sess_name[40];
330 struct work_struct release_work;
331 };
332
333 /**
334 * struct srpt_nexus - I_T nexus
335 * @rcu: RCU head for this data structure.
336 * @entry: srpt_port.nexus_list list node.
337 * @ch_list: struct srpt_rdma_ch list. Protected by srpt_port.mutex.
338 * @i_port_id: 128-bit initiator port identifier copied from SRP_LOGIN_REQ.
339 * @t_port_id: 128-bit target port identifier copied from SRP_LOGIN_REQ.
340 */
341 struct srpt_nexus {
342 struct rcu_head rcu;
343 struct list_head entry;
344 struct list_head ch_list;
345 u8 i_port_id[16];
346 u8 t_port_id[16];
347 };
348
349 /**
350 * struct srpt_port_attib - attributes for SRPT port
351 * @srp_max_rdma_size: Maximum size of SRP RDMA transfers for new connections.
352 * @srp_max_rsp_size: Maximum size of SRP response messages in bytes.
353 * @srp_sq_size: Shared receive queue (SRQ) size.
354 * @use_srq: Whether or not to use SRQ.
355 */
356 struct srpt_port_attrib {
357 u32 srp_max_rdma_size;
358 u32 srp_max_rsp_size;
359 u32 srp_sq_size;
360 bool use_srq;
361 };
362
363 /**
364 * struct srpt_port - information associated by SRPT with a single IB port
365 * @sdev: backpointer to the HCA information.
366 * @mad_agent: per-port management datagram processing information.
367 * @enabled: Whether or not this target port is enabled.
368 * @port_guid: ASCII representation of Port GUID
369 * @port_gid: ASCII representation of Port GID
370 * @port: one-based port number.
371 * @sm_lid: cached value of the port's sm_lid.
372 * @lid: cached value of the port's lid.
373 * @gid: cached value of the port's gid.
374 * @port_acl_lock spinlock for port_acl_list:
375 * @work: work structure for refreshing the aforementioned cached values.
376 * @port_guid_tpg: TPG associated with target port GUID.
377 * @port_guid_wwn: WWN associated with target port GUID.
378 * @port_gid_tpg: TPG associated with target port GID.
379 * @port_gid_wwn: WWN associated with target port GID.
380 * @port_attrib: Port attributes that can be accessed through configfs.
381 * @ch_releaseQ: Enables waiting for removal from nexus_list.
382 * @mutex: Protects nexus_list.
383 * @nexus_list: Nexus list. See also srpt_nexus.entry.
384 */
385 struct srpt_port {
386 struct srpt_device *sdev;
387 struct ib_mad_agent *mad_agent;
388 bool enabled;
389 u8 port_guid[24];
390 u8 port_gid[64];
391 u8 port;
392 u32 sm_lid;
393 u32 lid;
394 union ib_gid gid;
395 struct work_struct work;
396 struct se_portal_group port_guid_tpg;
397 struct se_wwn port_guid_wwn;
398 struct se_portal_group port_gid_tpg;
399 struct se_wwn port_gid_wwn;
400 struct srpt_port_attrib port_attrib;
401 wait_queue_head_t ch_releaseQ;
402 struct mutex mutex;
403 struct list_head nexus_list;
404 };
405
406 /**
407 * struct srpt_device - information associated by SRPT with a single HCA
408 * @device: Backpointer to the struct ib_device managed by the IB core.
409 * @pd: IB protection domain.
410 * @lkey: L_Key (local key) with write access to all local memory.
411 * @srq: Per-HCA SRQ (shared receive queue).
412 * @cm_id: Connection identifier.
413 * @srq_size: SRQ size.
414 * @sdev_mutex: Serializes use_srq changes.
415 * @use_srq: Whether or not to use SRQ.
416 * @req_buf_cache: kmem_cache for @ioctx_ring buffers.
417 * @ioctx_ring: Per-HCA SRQ.
418 * @event_handler: Per-HCA asynchronous IB event handler.
419 * @list: Node in srpt_dev_list.
420 * @port: Information about the ports owned by this HCA.
421 */
422 struct srpt_device {
423 struct ib_device *device;
424 struct ib_pd *pd;
425 u32 lkey;
426 struct ib_srq *srq;
427 struct ib_cm_id *cm_id;
428 int srq_size;
429 struct mutex sdev_mutex;
430 bool use_srq;
431 struct kmem_cache *req_buf_cache;
432 struct srpt_recv_ioctx **ioctx_ring;
433 struct ib_event_handler event_handler;
434 struct list_head list;
435 struct srpt_port port[];
436 };
437
438 #endif /* IB_SRPT_H */