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
46#include <scsi/srp.h>
47
48#include "ib_dm_mad.h"
49
50/*
51 * The prefix the ServiceName field must start with in the device management
52 * ServiceEntries attribute pair. See also the SRP specification.
53 */
54#define SRP_SERVICE_NAME_PREFIX		"SRP.T10:"
55
56enum {
57	/*
58	 * SRP IOControllerProfile attributes for SRP target ports that have
59	 * not been defined in <scsi/srp.h>. Source: section B.7, table B.7
60	 * in the SRP specification.
61	 */
62	SRP_PROTOCOL = 0x0108,
63	SRP_PROTOCOL_VERSION = 0x0001,
64	SRP_IO_SUBCLASS = 0x609e,
65	SRP_SEND_TO_IOC = 0x01,
66	SRP_SEND_FROM_IOC = 0x02,
67	SRP_RDMA_READ_FROM_IOC = 0x08,
68	SRP_RDMA_WRITE_FROM_IOC = 0x20,
69
70	/*
71	 * srp_login_cmd.req_flags bitmasks. See also table 9 in the SRP
72	 * specification.
73	 */
74	SRP_MTCH_ACTION = 0x03, /* MULTI-CHANNEL ACTION */
75	SRP_LOSOLNT = 0x10, /* logout solicited notification */
76	SRP_CRSOLNT = 0x20, /* credit request solicited notification */
77	SRP_AESOLNT = 0x40, /* asynchronous event solicited notification */
78
79	/*
80	 * srp_cmd.sol_nt / srp_tsk_mgmt.sol_not bitmasks. See also tables
81	 * 18 and 20 in the SRP specification.
82	 */
83	SRP_SCSOLNT = 0x02, /* SCSOLNT = successful solicited notification */
84	SRP_UCSOLNT = 0x04, /* UCSOLNT = unsuccessful solicited notification */
85
86	/*
87	 * srp_rsp.sol_not / srp_t_logout.sol_not bitmasks. See also tables
88	 * 16 and 22 in the SRP specification.
89	 */
90	SRP_SOLNT = 0x01, /* SOLNT = solicited notification */
91
92	/* See also table 24 in the SRP specification. */
93	SRP_TSK_MGMT_SUCCESS = 0x00,
94	SRP_TSK_MGMT_FUNC_NOT_SUPP = 0x04,
95	SRP_TSK_MGMT_FAILED = 0x05,
96
97	/* See also table 21 in the SRP specification. */
98	SRP_CMD_SIMPLE_Q = 0x0,
99	SRP_CMD_HEAD_OF_Q = 0x1,
100	SRP_CMD_ORDERED_Q = 0x2,
101	SRP_CMD_ACA = 0x4,
102
103	SRP_LOGIN_RSP_MULTICHAN_NO_CHAN = 0x0,
104	SRP_LOGIN_RSP_MULTICHAN_TERMINATED = 0x1,
105	SRP_LOGIN_RSP_MULTICHAN_MAINTAINED = 0x2,
106
107	SRPT_DEF_SG_TABLESIZE = 128,
108	SRPT_DEF_SG_PER_WQE = 16,
109
110	MIN_SRPT_SQ_SIZE = 16,
111	DEF_SRPT_SQ_SIZE = 4096,
112	SRPT_RQ_SIZE = 128,
113	MIN_SRPT_SRQ_SIZE = 4,
114	DEFAULT_SRPT_SRQ_SIZE = 4095,
115	MAX_SRPT_SRQ_SIZE = 65535,
116	MAX_SRPT_RDMA_SIZE = 1U << 24,
117	MAX_SRPT_RSP_SIZE = 1024,
118
119	MIN_MAX_REQ_SIZE = 996,
120	DEFAULT_MAX_REQ_SIZE
121		= sizeof(struct srp_cmd)/*48*/
122		+ sizeof(struct srp_indirect_buf)/*20*/
123		+ 128 * sizeof(struct srp_direct_buf)/*16*/,
124
125	MIN_MAX_RSP_SIZE = sizeof(struct srp_rsp)/*36*/ + 4,
126	DEFAULT_MAX_RSP_SIZE = 256, /* leaves 220 bytes for sense data */
127
128	DEFAULT_MAX_RDMA_SIZE = 65536,
129};
130
131enum srpt_opcode {
132	SRPT_RECV,
133	SRPT_SEND,
134	SRPT_RDMA_MID,
135	SRPT_RDMA_ABORT,
136	SRPT_RDMA_READ_LAST,
137	SRPT_RDMA_WRITE_LAST,
138};
139
140static inline u64 encode_wr_id(u8 opcode, u32 idx)
141{
142	return ((u64)opcode << 32) | idx;
143}
144static inline enum srpt_opcode opcode_from_wr_id(u64 wr_id)
145{
146	return wr_id >> 32;
147}
148static inline u32 idx_from_wr_id(u64 wr_id)
149{
150	return (u32)wr_id;
151}
152
153struct rdma_iu {
154	u64		raddr;
155	u32		rkey;
156	struct ib_sge	*sge;
157	u32		sge_cnt;
158	int		mem_id;
159};
160
161/**
162 * enum srpt_command_state - SCSI command state managed by SRPT.
163 * @SRPT_STATE_NEW:           New command arrived and is being processed.
164 * @SRPT_STATE_NEED_DATA:     Processing a write or bidir command and waiting
165 *                            for data arrival.
166 * @SRPT_STATE_DATA_IN:       Data for the write or bidir command arrived and is
167 *                            being processed.
168 * @SRPT_STATE_CMD_RSP_SENT:  SRP_RSP for SRP_CMD has been sent.
169 * @SRPT_STATE_MGMT:          Processing a SCSI task management command.
170 * @SRPT_STATE_MGMT_RSP_SENT: SRP_RSP for SRP_TSK_MGMT has been sent.
171 * @SRPT_STATE_DONE:          Command processing finished successfully, command
172 *                            processing has been aborted or command processing
173 *                            failed.
174 */
175enum srpt_command_state {
176	SRPT_STATE_NEW		 = 0,
177	SRPT_STATE_NEED_DATA	 = 1,
178	SRPT_STATE_DATA_IN	 = 2,
179	SRPT_STATE_CMD_RSP_SENT	 = 3,
180	SRPT_STATE_MGMT		 = 4,
181	SRPT_STATE_MGMT_RSP_SENT = 5,
182	SRPT_STATE_DONE		 = 6,
183};
184
185/**
186 * struct srpt_ioctx - Shared SRPT I/O context information.
187 * @buf:   Pointer to the buffer.
188 * @dma:   DMA address of the buffer.
189 * @index: Index of the I/O context in its ioctx_ring array.
190 */
191struct srpt_ioctx {
192	void			*buf;
193	dma_addr_t		dma;
194	uint32_t		index;
195};
196
197/**
198 * struct srpt_recv_ioctx - SRPT receive I/O context.
199 * @ioctx:     See above.
200 * @wait_list: Node for insertion in srpt_rdma_ch.cmd_wait_list.
201 */
202struct srpt_recv_ioctx {
203	struct srpt_ioctx	ioctx;
204	struct list_head	wait_list;
205};
206
207/**
208 * struct srpt_send_ioctx - SRPT send I/O context.
209 * @ioctx:       See above.
210 * @ch:          Channel pointer.
211 * @free_list:   Node in srpt_rdma_ch.free_list.
212 * @n_rbuf:      Number of data buffers in the received SRP command.
213 * @rbufs:       Pointer to SRP data buffer array.
214 * @single_rbuf: SRP data buffer if the command has only a single buffer.
215 * @sg:          Pointer to sg-list associated with this I/O context.
216 * @sg_cnt:      SG-list size.
217 * @mapped_sg_count: ib_dma_map_sg() return value.
218 * @n_rdma_ius:  Number of elements in the rdma_ius array.
219 * @rdma_ius:    Array with information about the RDMA mapping.
220 * @tag:         Tag of the received SRP information unit.
221 * @spinlock:    Protects 'state'.
222 * @state:       I/O context state.
223 * @rdma_aborted: If initiating a multipart RDMA transfer failed, whether
224 * 		 the already initiated transfers have finished.
225 * @cmd:         Target core command data structure.
226 * @sense_data:  SCSI sense data.
227 */
228struct srpt_send_ioctx {
229	struct srpt_ioctx	ioctx;
230	struct srpt_rdma_ch	*ch;
231	struct rdma_iu		*rdma_ius;
232	struct srp_direct_buf	*rbufs;
233	struct srp_direct_buf	single_rbuf;
234	struct scatterlist	*sg;
235	struct list_head	free_list;
236	spinlock_t		spinlock;
237	enum srpt_command_state	state;
238	bool			rdma_aborted;
239	struct se_cmd		cmd;
240	struct completion	tx_done;
241	u64			tag;
242	int			sg_cnt;
243	int			mapped_sg_count;
244	u16			n_rdma_ius;
245	u8			n_rdma;
246	u8			n_rbuf;
247	bool			queue_status_only;
248	u8			sense_data[SCSI_SENSE_BUFFERSIZE];
249};
250
251/**
252 * enum rdma_ch_state - SRP channel state.
253 * @CH_CONNECTING:	 QP is in RTR state; waiting for RTU.
254 * @CH_LIVE:		 QP is in RTS state.
255 * @CH_DISCONNECTING:    DREQ has been received; waiting for DREP
256 *                       or DREQ has been send and waiting for DREP
257 *                       or .
258 * @CH_DRAINING:	 QP is in ERR state; waiting for last WQE event.
259 * @CH_RELEASING:	 Last WQE event has been received; releasing resources.
260 */
261enum rdma_ch_state {
262	CH_CONNECTING,
263	CH_LIVE,
264	CH_DISCONNECTING,
265	CH_DRAINING,
266	CH_RELEASING
267};
268
269/**
270 * struct srpt_rdma_ch - RDMA channel.
271 * @wait_queue:    Allows the kernel thread to wait for more work.
272 * @thread:        Kernel thread that processes the IB queues associated with
273 *                 the channel.
274 * @cm_id:         IB CM ID associated with the channel.
275 * @qp:            IB queue pair used for communicating over this channel.
276 * @cq:            IB completion queue for this channel.
277 * @rq_size:       IB receive queue size.
278 * @rsp_size	   IB response message size in bytes.
279 * @sq_wr_avail:   number of work requests available in the send queue.
280 * @sport:         pointer to the information of the HCA port used by this
281 *                 channel.
282 * @i_port_id:     128-bit initiator port identifier copied from SRP_LOGIN_REQ.
283 * @t_port_id:     128-bit target port identifier copied from SRP_LOGIN_REQ.
284 * @max_ti_iu_len: maximum target-to-initiator information unit length.
285 * @req_lim:       request limit: maximum number of requests that may be sent
286 *                 by the initiator without having received a response.
287 * @req_lim_delta: Number of credits not yet sent back to the initiator.
288 * @spinlock:      Protects free_list and state.
289 * @free_list:     Head of list with free send I/O contexts.
290 * @state:         channel state. See also enum rdma_ch_state.
291 * @ioctx_ring:    Send ring.
292 * @wc:            IB work completion array for srpt_process_completion().
293 * @list:          Node for insertion in the srpt_device.rch_list list.
294 * @cmd_wait_list: List of SCSI commands that arrived before the RTU event. This
295 *                 list contains struct srpt_ioctx elements and is protected
296 *                 against concurrent modification by the cm_id spinlock.
297 * @sess:          Session information associated with this SRP channel.
298 * @sess_name:     Session name.
299 * @release_work:  Allows scheduling of srpt_release_channel().
300 * @release_done:  Enables waiting for srpt_release_channel() completion.
301 */
302struct srpt_rdma_ch {
303	wait_queue_head_t	wait_queue;
304	struct task_struct	*thread;
305	struct ib_cm_id		*cm_id;
306	struct ib_qp		*qp;
307	struct ib_cq		*cq;
308	int			rq_size;
309	u32			rsp_size;
310	atomic_t		sq_wr_avail;
311	struct srpt_port	*sport;
312	u8			i_port_id[16];
313	u8			t_port_id[16];
314	int			max_ti_iu_len;
315	atomic_t		req_lim;
316	atomic_t		req_lim_delta;
317	spinlock_t		spinlock;
318	struct list_head	free_list;
319	enum rdma_ch_state	state;
320	struct srpt_send_ioctx	**ioctx_ring;
321	struct ib_wc		wc[16];
322	struct list_head	list;
323	struct list_head	cmd_wait_list;
324	struct se_session	*sess;
325	u8			sess_name[36];
326	struct work_struct	release_work;
327	struct completion	*release_done;
328	bool			in_shutdown;
329};
330
331/**
332 * struct srpt_port_attib - Attributes for SRPT port
333 * @srp_max_rdma_size: Maximum size of SRP RDMA transfers for new connections.
334 * @srp_max_rsp_size: Maximum size of SRP response messages in bytes.
335 * @srp_sq_size: Shared receive queue (SRQ) size.
336 */
337struct srpt_port_attrib {
338	u32			srp_max_rdma_size;
339	u32			srp_max_rsp_size;
340	u32			srp_sq_size;
341};
342
343/**
344 * struct srpt_port - Information associated by SRPT with a single IB port.
345 * @sdev:      backpointer to the HCA information.
346 * @mad_agent: per-port management datagram processing information.
347 * @enabled:   Whether or not this target port is enabled.
348 * @port_guid: ASCII representation of Port GUID
349 * @port:      one-based port number.
350 * @sm_lid:    cached value of the port's sm_lid.
351 * @lid:       cached value of the port's lid.
352 * @gid:       cached value of the port's gid.
353 * @port_acl_lock spinlock for port_acl_list:
354 * @work:      work structure for refreshing the aforementioned cached values.
355 * @port_tpg_1 Target portal group = 1 data.
356 * @port_wwn:  Target core WWN data.
357 * @port_acl_list: Head of the list with all node ACLs for this port.
358 */
359struct srpt_port {
360	struct srpt_device	*sdev;
361	struct ib_mad_agent	*mad_agent;
362	bool			enabled;
363	u8			port_guid[64];
364	u8			port;
365	u16			sm_lid;
366	u16			lid;
367	union ib_gid		gid;
368	spinlock_t		port_acl_lock;
369	struct work_struct	work;
370	struct se_portal_group	port_tpg_1;
371	struct se_wwn		port_wwn;
372	struct list_head	port_acl_list;
373	struct srpt_port_attrib port_attrib;
374};
375
376/**
377 * struct srpt_device - Information associated by SRPT with a single HCA.
378 * @device:        Backpointer to the struct ib_device managed by the IB core.
379 * @pd:            IB protection domain.
380 * @mr:            L_Key (local key) with write access to all local memory.
381 * @srq:           Per-HCA SRQ (shared receive queue).
382 * @cm_id:         Connection identifier.
383 * @dev_attr:      Attributes of the InfiniBand device as obtained during the
384 *                 ib_client.add() callback.
385 * @srq_size:      SRQ size.
386 * @ioctx_ring:    Per-HCA SRQ.
387 * @rch_list:      Per-device channel list -- see also srpt_rdma_ch.list.
388 * @ch_releaseQ:   Enables waiting for removal from rch_list.
389 * @spinlock:      Protects rch_list and tpg.
390 * @port:          Information about the ports owned by this HCA.
391 * @event_handler: Per-HCA asynchronous IB event handler.
392 * @list:          Node in srpt_dev_list.
393 */
394struct srpt_device {
395	struct ib_device	*device;
396	struct ib_pd		*pd;
397	struct ib_mr		*mr;
398	struct ib_srq		*srq;
399	struct ib_cm_id		*cm_id;
400	struct ib_device_attr	dev_attr;
401	int			srq_size;
402	struct srpt_recv_ioctx	**ioctx_ring;
403	struct list_head	rch_list;
404	wait_queue_head_t	ch_releaseQ;
405	spinlock_t		spinlock;
406	struct srpt_port	port[2];
407	struct ib_event_handler	event_handler;
408	struct list_head	list;
409};
410
411/**
412 * struct srpt_node_acl - Per-initiator ACL data (managed via configfs).
413 * @i_port_id: 128-bit SRP initiator port ID.
414 * @sport:     port information.
415 * @nacl:      Target core node ACL information.
416 * @list:      Element of the per-HCA ACL list.
417 */
418struct srpt_node_acl {
419	u8			i_port_id[16];
420	struct srpt_port	*sport;
421	struct se_node_acl	nacl;
422	struct list_head	list;
423};
424
425/*
426 * SRP-releated SCSI persistent reservation definitions.
427 *
428 * See also SPC4r28, section 7.6.1 (Protocol specific parameters introduction).
429 * See also SPC4r28, section 7.6.4.5 (TransportID for initiator ports using
430 * SCSI over an RDMA interface).
431 */
432
433enum {
434	SCSI_TRANSPORTID_PROTOCOLID_SRP	= 4,
435};
436
437struct spc_rdma_transport_id {
438	uint8_t protocol_identifier;
439	uint8_t reserved[7];
440	uint8_t i_port_id[16];
441};
442
443#endif				/* IB_SRPT_H */
444