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
58struct srpt_nexus;
59
60enum {
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 MIN_SRPT_SQ_SIZE = 16,
110 DEF_SRPT_SQ_SIZE = 4096,
111 MAX_SRPT_RQ_SIZE = 128,
112 MIN_SRPT_SRQ_SIZE = 4,
113 DEFAULT_SRPT_SRQ_SIZE = 4095,
114 MAX_SRPT_SRQ_SIZE = 65535,
115 MAX_SRPT_RDMA_SIZE = 1U << 24,
116 MAX_SRPT_RSP_SIZE = 1024,
117
118 SRP_MAX_ADD_CDB_LEN = 16,
119 SRP_MAX_IMM_DATA_OFFSET = 80,
120 SRP_MAX_IMM_DATA = 8 * 1024,
121 MIN_MAX_REQ_SIZE = 996,
122 DEFAULT_MAX_REQ_SIZE_1 = sizeof(struct srp_cmd)/*48*/ +
123 SRP_MAX_ADD_CDB_LEN +
124 sizeof(struct srp_indirect_buf)/*20*/ +
125 128 * sizeof(struct srp_direct_buf)/*16*/,
126 DEFAULT_MAX_REQ_SIZE_2 = SRP_MAX_IMM_DATA_OFFSET +
127 sizeof(struct srp_imm_buf) + SRP_MAX_IMM_DATA,
128 DEFAULT_MAX_REQ_SIZE = DEFAULT_MAX_REQ_SIZE_1 > DEFAULT_MAX_REQ_SIZE_2 ?
129 DEFAULT_MAX_REQ_SIZE_1 : DEFAULT_MAX_REQ_SIZE_2,
130
131 MIN_MAX_RSP_SIZE = sizeof(struct srp_rsp)/*36*/ + 4,
132 DEFAULT_MAX_RSP_SIZE = 256, /* leaves 220 bytes for sense data */
133
134 DEFAULT_MAX_RDMA_SIZE = 65536,
135};
136
137/**
138 * enum srpt_command_state - SCSI command state managed by SRPT
139 * @SRPT_STATE_NEW: New command arrived and is being processed.
140 * @SRPT_STATE_NEED_DATA: Processing a write or bidir command and waiting
141 * for data arrival.
142 * @SRPT_STATE_DATA_IN: Data for the write or bidir command arrived and is
143 * being processed.
144 * @SRPT_STATE_CMD_RSP_SENT: SRP_RSP for SRP_CMD has been sent.
145 * @SRPT_STATE_MGMT: Processing a SCSI task management command.
146 * @SRPT_STATE_MGMT_RSP_SENT: SRP_RSP for SRP_TSK_MGMT has been sent.
147 * @SRPT_STATE_DONE: Command processing finished successfully, command
148 * processing has been aborted or command processing
149 * failed.
150 */
151enum srpt_command_state {
152 SRPT_STATE_NEW = 0,
153 SRPT_STATE_NEED_DATA = 1,
154 SRPT_STATE_DATA_IN = 2,
155 SRPT_STATE_CMD_RSP_SENT = 3,
156 SRPT_STATE_MGMT = 4,
157 SRPT_STATE_MGMT_RSP_SENT = 5,
158 SRPT_STATE_DONE = 6,
159};
160
161/**
162 * struct srpt_ioctx - shared SRPT I/O context information
163 * @cqe: Completion queue element.
164 * @buf: Pointer to the buffer.
165 * @dma: DMA address of the buffer.
166 * @offset: Offset of the first byte in @buf and @dma that is actually used.
167 * @index: Index of the I/O context in its ioctx_ring array.
168 */
169struct srpt_ioctx {
170 struct ib_cqe cqe;
171 void *buf;
172 dma_addr_t dma;
173 uint32_t offset;
174 uint32_t index;
175};
176
177/**
178 * struct srpt_recv_ioctx - SRPT receive I/O context
179 * @ioctx: See above.
180 * @wait_list: Node for insertion in srpt_rdma_ch.cmd_wait_list.
181 * @byte_len: Number of bytes in @ioctx.buf.
182 */
183struct srpt_recv_ioctx {
184 struct srpt_ioctx ioctx;
185 struct list_head wait_list;
186 int byte_len;
187};
188
189struct srpt_rw_ctx {
190 struct rdma_rw_ctx rw;
191 struct scatterlist *sg;
192 unsigned int nents;
193};
194
195/**
196 * struct srpt_send_ioctx - SRPT send I/O context
197 * @ioctx: See above.
198 * @ch: Channel pointer.
199 * @recv_ioctx: Receive I/O context associated with this send I/O context.
200 * Only used for processing immediate data.
201 * @s_rw_ctx: @rw_ctxs points here if only a single rw_ctx is needed.
202 * @rw_ctxs: RDMA read/write contexts.
203 * @imm_sg: Scatterlist for immediate data.
204 * @rdma_cqe: RDMA completion queue element.
205 * @state: I/O context state.
206 * @cmd: Target core command data structure.
207 * @sense_data: SCSI sense data.
208 * @n_rdma: Number of work requests needed to transfer this ioctx.
209 * @n_rw_ctx: Size of rw_ctxs array.
210 * @queue_status_only: Send a SCSI status back to the initiator but no data.
211 * @sense_data: Sense data to be sent to the initiator.
212 */
213struct srpt_send_ioctx {
214 struct srpt_ioctx ioctx;
215 struct srpt_rdma_ch *ch;
216 struct srpt_recv_ioctx *recv_ioctx;
217
218 struct srpt_rw_ctx s_rw_ctx;
219 struct srpt_rw_ctx *rw_ctxs;
220
221 struct scatterlist imm_sg;
222
223 struct ib_cqe rdma_cqe;
224 enum srpt_command_state state;
225 struct se_cmd cmd;
226 u8 n_rdma;
227 u8 n_rw_ctx;
228 bool queue_status_only;
229 u8 sense_data[TRANSPORT_SENSE_BUFFER];
230};
231
232/**
233 * enum rdma_ch_state - SRP channel state
234 * @CH_CONNECTING: QP is in RTR state; waiting for RTU.
235 * @CH_LIVE: QP is in RTS state.
236 * @CH_DISCONNECTING: DREQ has been sent and waiting for DREP or DREQ has
237 * been received.
238 * @CH_DRAINING: DREP has been received or waiting for DREP timed out
239 * and last work request has been queued.
240 * @CH_DISCONNECTED: Last completion has been received.
241 */
242enum rdma_ch_state {
243 CH_CONNECTING,
244 CH_LIVE,
245 CH_DISCONNECTING,
246 CH_DRAINING,
247 CH_DISCONNECTED,
248};
249
250/**
251 * struct srpt_rdma_ch - RDMA channel
252 * @nexus: I_T nexus this channel is associated with.
253 * @qp: IB queue pair used for communicating over this channel.
254 * @ib_cm: See below.
255 * @ib_cm.cm_id: IB CM ID associated with the channel.
256 * @rdma_cm: See below.
257 * @rdma_cm.cm_id: RDMA CM ID associated with the channel.
258 * @cq: IB completion queue for this channel.
259 * @cq_size: Number of CQEs in @cq.
260 * @zw_cqe: Zero-length write CQE.
261 * @rcu: RCU head.
262 * @kref: kref for this channel.
263 * @closed: Completion object that will be signaled as soon as a new
264 * channel object with the same identity can be created.
265 * @rq_size: IB receive queue size.
266 * @max_rsp_size: Maximum size of an RSP response message in bytes.
267 * @sq_wr_avail: number of work requests available in the send queue.
268 * @sport: pointer to the information of the HCA port used by this
269 * channel.
270 * @max_ti_iu_len: maximum target-to-initiator information unit length.
271 * @req_lim: request limit: maximum number of requests that may be sent
272 * by the initiator without having received a response.
273 * @req_lim_delta: Number of credits not yet sent back to the initiator.
274 * @imm_data_offset: Offset from start of SRP_CMD for immediate data.
275 * @spinlock: Protects free_list and state.
276 * @state: channel state. See also enum rdma_ch_state.
277 * @using_rdma_cm: Whether the RDMA/CM or IB/CM is used for this channel.
278 * @processing_wait_list: Whether or not cmd_wait_list is being processed.
279 * @rsp_buf_cache: kmem_cache for @ioctx_ring.
280 * @ioctx_ring: Send ring.
281 * @req_buf_cache: kmem_cache for @ioctx_recv_ring.
282 * @ioctx_recv_ring: Receive I/O context ring.
283 * @list: Node in srpt_nexus.ch_list.
284 * @cmd_wait_list: List of SCSI commands that arrived before the RTU event. This
285 * list contains struct srpt_ioctx elements and is protected
286 * against concurrent modification by the cm_id spinlock.
287 * @pkey: P_Key of the IB partition for this SRP channel.
288 * @sess: Session information associated with this SRP channel.
289 * @sess_name: Session name.
290 * @release_work: Allows scheduling of srpt_release_channel().
291 */
292struct srpt_rdma_ch {
293 struct srpt_nexus *nexus;
294 struct ib_qp *qp;
295 union {
296 struct {
297 struct ib_cm_id *cm_id;
298 } ib_cm;
299 struct {
300 struct rdma_cm_id *cm_id;
301 } rdma_cm;
302 };
303 struct ib_cq *cq;
304 u32 cq_size;
305 struct ib_cqe zw_cqe;
306 struct rcu_head rcu;
307 struct kref kref;
308 struct completion *closed;
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 */
341struct 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_attrib - 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 */
356struct 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_tpg - information about a single "target portal group"
365 * @entry: Entry in @sport_id->tpg_list.
366 * @sport_id: Port name this TPG is associated with.
367 * @tpg: LIO TPG data structure.
368 *
369 * Zero or more target portal groups are associated with each port name
370 * (srpt_port_id). With each TPG an ACL list is associated.
371 */
372struct srpt_tpg {
373 struct list_head entry;
374 struct srpt_port_id *sport_id;
375 struct se_portal_group tpg;
376};
377
378/**
379 * struct srpt_port_id - LIO RDMA port information
380 * @mutex: Protects @tpg_list changes.
381 * @tpg_list: TPGs associated with the RDMA port name.
382 * @wwn: WWN associated with the RDMA port name.
383 * @name: ASCII representation of the port name.
384 *
385 * Multiple sysfs directories can be associated with a single RDMA port. This
386 * data structure represents a single (port, name) pair.
387 */
388struct srpt_port_id {
389 struct mutex mutex;
390 struct list_head tpg_list;
391 struct se_wwn wwn;
392 char name[64];
393};
394
395/**
396 * struct srpt_port - SRPT RDMA port information
397 * @sdev: backpointer to the HCA information.
398 * @mad_agent: per-port management datagram processing information.
399 * @enabled: Whether or not this target port is enabled.
400 * @port: one-based port number.
401 * @sm_lid: cached value of the port's sm_lid.
402 * @lid: cached value of the port's lid.
403 * @gid: cached value of the port's gid.
404 * @work: work structure for refreshing the aforementioned cached values.
405 * @guid_name: port name in GUID format.
406 * @guid_id: LIO target port information for the port name in GUID format.
407 * @gid_name: port name in GID format.
408 * @gid_id: LIO target port information for the port name in GID format.
409 * @port_attrib: Port attributes that can be accessed through configfs.
410 * @refcount: Number of objects associated with this port.
411 * @freed_channels: Completion that will be signaled once @refcount becomes 0.
412 * @mutex: Protects nexus_list.
413 * @nexus_list: Nexus list. See also srpt_nexus.entry.
414 */
415struct srpt_port {
416 struct srpt_device *sdev;
417 struct ib_mad_agent *mad_agent;
418 bool enabled;
419 u8 port;
420 u32 sm_lid;
421 u32 lid;
422 union ib_gid gid;
423 struct work_struct work;
424 char guid_name[64];
425 struct srpt_port_id *guid_id;
426 char gid_name[64];
427 struct srpt_port_id *gid_id;
428 struct srpt_port_attrib port_attrib;
429 atomic_t refcount;
430 struct completion *freed_channels;
431 struct mutex mutex;
432 struct list_head nexus_list;
433};
434
435/**
436 * struct srpt_device - information associated by SRPT with a single HCA
437 * @refcnt: Reference count for this device.
438 * @device: Backpointer to the struct ib_device managed by the IB core.
439 * @pd: IB protection domain.
440 * @lkey: L_Key (local key) with write access to all local memory.
441 * @srq: Per-HCA SRQ (shared receive queue).
442 * @cm_id: Connection identifier.
443 * @srq_size: SRQ size.
444 * @sdev_mutex: Serializes use_srq changes.
445 * @use_srq: Whether or not to use SRQ.
446 * @req_buf_cache: kmem_cache for @ioctx_ring buffers.
447 * @ioctx_ring: Per-HCA SRQ.
448 * @event_handler: Per-HCA asynchronous IB event handler.
449 * @list: Node in srpt_dev_list.
450 * @port: Information about the ports owned by this HCA.
451 */
452struct srpt_device {
453 struct kref refcnt;
454 struct ib_device *device;
455 struct ib_pd *pd;
456 u32 lkey;
457 struct ib_srq *srq;
458 struct ib_cm_id *cm_id;
459 int srq_size;
460 struct mutex sdev_mutex;
461 bool use_srq;
462 struct kmem_cache *req_buf_cache;
463 struct srpt_recv_ioctx **ioctx_ring;
464 struct ib_event_handler event_handler;
465 struct list_head list;
466 struct srpt_port port[];
467};
468
469#endif /* IB_SRPT_H */
470

source code of linux/drivers/infiniband/ulp/srpt/ib_srpt.h