1 /*
2 * iSER transport for the Open iSCSI Initiator & iSER transport internals
3 *
4 * Copyright (C) 2004 Dmitry Yusupov
5 * Copyright (C) 2004 Alex Aizman
6 * Copyright (C) 2005 Mike Christie
7 * based on code maintained by open-iscsi@googlegroups.com
8 *
9 * Copyright (c) 2004, 2005, 2006 Voltaire, Inc. All rights reserved.
10 * Copyright (c) 2005, 2006 Cisco Systems. All rights reserved.
11 * Copyright (c) 2013-2014 Mellanox Technologies. All rights reserved.
12 *
13 * This software is available to you under a choice of one of two
14 * licenses. You may choose to be licensed under the terms of the GNU
15 * General Public License (GPL) Version 2, available from the file
16 * COPYING in the main directory of this source tree, or the
17 * OpenIB.org BSD license below:
18 *
19 * Redistribution and use in source and binary forms, with or
20 * without modification, are permitted provided that the following
21 * conditions are met:
22 *
23 * - Redistributions of source code must retain the above
24 * copyright notice, this list of conditions and the following
25 * disclaimer.
26 *
27 * - Redistributions in binary form must reproduce the above
28 * copyright notice, this list of conditions and the following
29 * disclaimer in the documentation and/or other materials
30 * provided with the distribution.
31 *
32 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
33 * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
34 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
35 * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
36 * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
37 * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
38 * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
39 * SOFTWARE.
40 */
41 #ifndef __ISCSI_ISER_H__
42 #define __ISCSI_ISER_H__
43
44 #include <linux/types.h>
45 #include <linux/net.h>
46 #include <linux/printk.h>
47 #include <scsi/libiscsi.h>
48 #include <scsi/scsi_transport_iscsi.h>
49 #include <scsi/scsi_cmnd.h>
50 #include <scsi/scsi_device.h>
51 #include <scsi/iser.h>
52
53 #include <linux/interrupt.h>
54 #include <linux/wait.h>
55 #include <linux/sched.h>
56 #include <linux/list.h>
57 #include <linux/slab.h>
58 #include <linux/dma-mapping.h>
59 #include <linux/mutex.h>
60 #include <linux/mempool.h>
61 #include <linux/uio.h>
62
63 #include <linux/socket.h>
64 #include <linux/in.h>
65 #include <linux/in6.h>
66
67 #include <rdma/ib_verbs.h>
68 #include <rdma/rdma_cm.h>
69
70 #define DRV_NAME "iser"
71 #define PFX DRV_NAME ": "
72 #define DRV_VER "1.6"
73
74 #define iser_dbg(fmt, arg...) \
75 do { \
76 if (unlikely(iser_debug_level > 2)) \
77 printk(KERN_DEBUG PFX "%s: " fmt,\
78 __func__ , ## arg); \
79 } while (0)
80
81 #define iser_warn(fmt, arg...) \
82 do { \
83 if (unlikely(iser_debug_level > 0)) \
84 pr_warn(PFX "%s: " fmt, \
85 __func__ , ## arg); \
86 } while (0)
87
88 #define iser_info(fmt, arg...) \
89 do { \
90 if (unlikely(iser_debug_level > 1)) \
91 pr_info(PFX "%s: " fmt, \
92 __func__ , ## arg); \
93 } while (0)
94
95 #define iser_err(fmt, arg...) \
96 pr_err(PFX "%s: " fmt, __func__ , ## arg)
97
98 /* Default support is 512KB I/O size */
99 #define ISER_DEF_MAX_SECTORS 1024
100 #define ISCSI_ISER_DEF_SG_TABLESIZE \
101 ((ISER_DEF_MAX_SECTORS * SECTOR_SIZE) >> ilog2(SZ_4K))
102 /* Maximum support is 16MB I/O size */
103 #define ISCSI_ISER_MAX_SG_TABLESIZE ((32768 * SECTOR_SIZE) >> ilog2(SZ_4K))
104
105 #define ISER_DEF_XMIT_CMDS_DEFAULT 512
106 #if ISCSI_DEF_XMIT_CMDS_MAX > ISER_DEF_XMIT_CMDS_DEFAULT
107 #define ISER_DEF_XMIT_CMDS_MAX ISCSI_DEF_XMIT_CMDS_MAX
108 #else
109 #define ISER_DEF_XMIT_CMDS_MAX ISER_DEF_XMIT_CMDS_DEFAULT
110 #endif
111 #define ISER_DEF_CMD_PER_LUN ISER_DEF_XMIT_CMDS_MAX
112
113 /* QP settings */
114 /* Maximal bounds on received asynchronous PDUs */
115 #define ISER_MAX_RX_MISC_PDUS 4 /* NOOP_IN(2) , ASYNC_EVENT(2) */
116
117 #define ISER_MAX_TX_MISC_PDUS 6 /* NOOP_OUT(2), TEXT(1), *
118 * SCSI_TMFUNC(2), LOGOUT(1) */
119
120 #define ISER_QP_MAX_RECV_DTOS (ISER_DEF_XMIT_CMDS_MAX)
121
122 #define ISER_MIN_POSTED_RX (ISER_DEF_XMIT_CMDS_MAX >> 2)
123
124 /* the max TX (send) WR supported by the iSER QP is defined by *
125 * max_send_wr = T * (1 + D) + C ; D is how many inflight dataouts we expect *
126 * to have at max for SCSI command. The tx posting & completion handling code *
127 * supports -EAGAIN scheme where tx is suspended till the QP has room for more *
128 * send WR. D=8 comes from 64K/8K */
129
130 #define ISER_INFLIGHT_DATAOUTS 8
131
132 #define ISER_QP_MAX_REQ_DTOS (ISER_DEF_XMIT_CMDS_MAX * \
133 (1 + ISER_INFLIGHT_DATAOUTS) + \
134 ISER_MAX_TX_MISC_PDUS + \
135 ISER_MAX_RX_MISC_PDUS)
136
137 /* Max registration work requests per command */
138 #define ISER_MAX_REG_WR_PER_CMD 5
139
140 /* For Signature we don't support DATAOUTs so no need to make room for them */
141 #define ISER_QP_SIG_MAX_REQ_DTOS (ISER_DEF_XMIT_CMDS_MAX * \
142 (1 + ISER_MAX_REG_WR_PER_CMD) + \
143 ISER_MAX_TX_MISC_PDUS + \
144 ISER_MAX_RX_MISC_PDUS)
145
146 #define ISER_GET_MAX_XMIT_CMDS(send_wr) ((send_wr \
147 - ISER_MAX_TX_MISC_PDUS \
148 - ISER_MAX_RX_MISC_PDUS) / \
149 (1 + ISER_INFLIGHT_DATAOUTS))
150
151 #define ISER_SIGNAL_CMD_COUNT 32
152
153 /* Constant PDU lengths calculations */
154 #define ISER_HEADERS_LEN (sizeof(struct iser_ctrl) + sizeof(struct iscsi_hdr))
155
156 #define ISER_RECV_DATA_SEG_LEN 128
157 #define ISER_RX_PAYLOAD_SIZE (ISER_HEADERS_LEN + ISER_RECV_DATA_SEG_LEN)
158 #define ISER_RX_LOGIN_SIZE (ISER_HEADERS_LEN + ISCSI_DEF_MAX_RECV_SEG_LEN)
159
160 /* Length of an object name string */
161 #define ISER_OBJECT_NAME_SIZE 64
162
163 enum iser_conn_state {
164 ISER_CONN_INIT, /* descriptor allocd, no conn */
165 ISER_CONN_PENDING, /* in the process of being established */
166 ISER_CONN_UP, /* up and running */
167 ISER_CONN_TERMINATING, /* in the process of being terminated */
168 ISER_CONN_DOWN, /* shut down */
169 ISER_CONN_STATES_NUM
170 };
171
172 enum iser_task_status {
173 ISER_TASK_STATUS_INIT = 0,
174 ISER_TASK_STATUS_STARTED,
175 ISER_TASK_STATUS_COMPLETED
176 };
177
178 enum iser_data_dir {
179 ISER_DIR_IN = 0, /* to initiator */
180 ISER_DIR_OUT, /* from initiator */
181 ISER_DIRS_NUM
182 };
183
184 /**
185 * struct iser_data_buf - iSER data buffer
186 *
187 * @sg: pointer to the sg list
188 * @size: num entries of this sg
189 * @data_len: total beffer byte len
190 * @dma_nents: returned by dma_map_sg
191 */
192 struct iser_data_buf {
193 struct scatterlist *sg;
194 int size;
195 unsigned long data_len;
196 int dma_nents;
197 };
198
199 /* fwd declarations */
200 struct iser_device;
201 struct iscsi_iser_task;
202 struct iscsi_endpoint;
203 struct iser_reg_resources;
204
205 /**
206 * struct iser_mem_reg - iSER memory registration info
207 *
208 * @sge: memory region sg element
209 * @rkey: memory region remote key
210 * @mem_h: pointer to registration context (FMR/Fastreg)
211 */
212 struct iser_mem_reg {
213 struct ib_sge sge;
214 u32 rkey;
215 void *mem_h;
216 };
217
218 enum iser_desc_type {
219 ISCSI_TX_CONTROL ,
220 ISCSI_TX_SCSI_COMMAND,
221 ISCSI_TX_DATAOUT
222 };
223
224 /**
225 * struct iser_tx_desc - iSER TX descriptor
226 *
227 * @iser_header: iser header
228 * @iscsi_header: iscsi header
229 * @type: command/control/dataout
230 * @dma_addr: header buffer dma_address
231 * @tx_sg: sg[0] points to iser/iscsi headers
232 * sg[1] optionally points to either of immediate data
233 * unsolicited data-out or control
234 * @num_sge: number sges used on this TX task
235 * @cqe: completion handler
236 * @mapped: Is the task header mapped
237 * @reg_wr: registration WR
238 * @send_wr: send WR
239 * @inv_wr: invalidate WR
240 */
241 struct iser_tx_desc {
242 struct iser_ctrl iser_header;
243 struct iscsi_hdr iscsi_header;
244 enum iser_desc_type type;
245 u64 dma_addr;
246 struct ib_sge tx_sg[2];
247 int num_sge;
248 struct ib_cqe cqe;
249 bool mapped;
250 struct ib_reg_wr reg_wr;
251 struct ib_send_wr send_wr;
252 struct ib_send_wr inv_wr;
253 };
254
255 #define ISER_RX_PAD_SIZE (256 - (ISER_RX_PAYLOAD_SIZE + \
256 sizeof(u64) + sizeof(struct ib_sge) + \
257 sizeof(struct ib_cqe)))
258 /**
259 * struct iser_rx_desc - iSER RX descriptor
260 *
261 * @iser_header: iser header
262 * @iscsi_header: iscsi header
263 * @data: received data segment
264 * @dma_addr: receive buffer dma address
265 * @rx_sg: ib_sge of receive buffer
266 * @cqe: completion handler
267 * @pad: for sense data TODO: Modify to maximum sense length supported
268 */
269 struct iser_rx_desc {
270 struct iser_ctrl iser_header;
271 struct iscsi_hdr iscsi_header;
272 char data[ISER_RECV_DATA_SEG_LEN];
273 u64 dma_addr;
274 struct ib_sge rx_sg;
275 struct ib_cqe cqe;
276 char pad[ISER_RX_PAD_SIZE];
277 } __packed;
278
279 /**
280 * struct iser_login_desc - iSER login descriptor
281 *
282 * @req: pointer to login request buffer
283 * @rsp: pointer to login response buffer
284 * @req_dma: DMA address of login request buffer
285 * @rsp_dma: DMA address of login response buffer
286 * @sge: IB sge for login post recv
287 * @cqe: completion handler
288 */
289 struct iser_login_desc {
290 void *req;
291 void *rsp;
292 u64 req_dma;
293 u64 rsp_dma;
294 struct ib_sge sge;
295 struct ib_cqe cqe;
296 } __packed;
297
298 struct iser_conn;
299 struct ib_conn;
300
301 /**
302 * struct iser_device - iSER device handle
303 *
304 * @ib_device: RDMA device
305 * @pd: Protection Domain for this device
306 * @mr: Global DMA memory region
307 * @event_handler: IB events handle routine
308 * @ig_list: entry in devices list
309 * @refcount: Reference counter, dominated by open iser connections
310 */
311 struct iser_device {
312 struct ib_device *ib_device;
313 struct ib_pd *pd;
314 struct ib_event_handler event_handler;
315 struct list_head ig_list;
316 int refcount;
317 };
318
319 /**
320 * struct iser_reg_resources - Fast registration resources
321 *
322 * @mr: memory region
323 * @sig_mr: signature memory region
324 * @mr_valid: is mr valid indicator
325 */
326 struct iser_reg_resources {
327 struct ib_mr *mr;
328 struct ib_mr *sig_mr;
329 u8 mr_valid:1;
330 };
331
332 /**
333 * struct iser_fr_desc - Fast registration descriptor
334 *
335 * @list: entry in connection fastreg pool
336 * @rsc: data buffer registration resources
337 * @sig_protected: is region protected indicator
338 * @all_list: first and last list members
339 */
340 struct iser_fr_desc {
341 struct list_head list;
342 struct iser_reg_resources rsc;
343 bool sig_protected;
344 struct list_head all_list;
345 };
346
347 /**
348 * struct iser_fr_pool - connection fast registration pool
349 *
350 * @list: list of fastreg descriptors
351 * @lock: protects fastreg pool
352 * @size: size of the pool
353 * @all_list: first and last list members
354 */
355 struct iser_fr_pool {
356 struct list_head list;
357 spinlock_t lock;
358 int size;
359 struct list_head all_list;
360 };
361
362 /**
363 * struct ib_conn - Infiniband related objects
364 *
365 * @cma_id: rdma_cm connection maneger handle
366 * @qp: Connection Queue-pair
367 * @cq: Connection completion queue
368 * @cq_size: The number of max outstanding completions
369 * @post_recv_buf_count: post receive counter
370 * @sig_count: send work request signal count
371 * @rx_wr: receive work request for batch posts
372 * @device: reference to iser device
373 * @fr_pool: connection fast registration poool
374 * @pi_support: Indicate device T10-PI support
375 * @reg_cqe: completion handler
376 */
377 struct ib_conn {
378 struct rdma_cm_id *cma_id;
379 struct ib_qp *qp;
380 struct ib_cq *cq;
381 u32 cq_size;
382 int post_recv_buf_count;
383 u8 sig_count;
384 struct ib_recv_wr rx_wr[ISER_MIN_POSTED_RX];
385 struct iser_device *device;
386 struct iser_fr_pool fr_pool;
387 bool pi_support;
388 struct ib_cqe reg_cqe;
389 };
390
391 /**
392 * struct iser_conn - iSER connection context
393 *
394 * @ib_conn: connection RDMA resources
395 * @iscsi_conn: link to matching iscsi connection
396 * @ep: transport handle
397 * @state: connection logical state
398 * @qp_max_recv_dtos: maximum number of data outs, corresponds
399 * to max number of post recvs
400 * @qp_max_recv_dtos_mask: (qp_max_recv_dtos - 1)
401 * @min_posted_rx: (qp_max_recv_dtos >> 2)
402 * @max_cmds: maximum cmds allowed for this connection
403 * @name: connection peer portal
404 * @release_work: deffered work for release job
405 * @state_mutex: protects iser onnection state
406 * @stop_completion: conn_stop completion
407 * @ib_completion: RDMA cleanup completion
408 * @up_completion: connection establishment completed
409 * (state is ISER_CONN_UP)
410 * @conn_list: entry in ig conn list
411 * @login_desc: login descriptor
412 * @rx_desc_head: head of rx_descs cyclic buffer
413 * @rx_descs: rx buffers array (cyclic buffer)
414 * @num_rx_descs: number of rx descriptors
415 * @scsi_sg_tablesize: scsi host sg_tablesize
416 * @pages_per_mr: maximum pages available for registration
417 * @snd_w_inv: connection uses remote invalidation
418 */
419 struct iser_conn {
420 struct ib_conn ib_conn;
421 struct iscsi_conn *iscsi_conn;
422 struct iscsi_endpoint *ep;
423 enum iser_conn_state state;
424 unsigned qp_max_recv_dtos;
425 unsigned qp_max_recv_dtos_mask;
426 unsigned min_posted_rx;
427 u16 max_cmds;
428 char name[ISER_OBJECT_NAME_SIZE];
429 struct work_struct release_work;
430 struct mutex state_mutex;
431 struct completion stop_completion;
432 struct completion ib_completion;
433 struct completion up_completion;
434 struct list_head conn_list;
435 struct iser_login_desc login_desc;
436 unsigned int rx_desc_head;
437 struct iser_rx_desc *rx_descs;
438 u32 num_rx_descs;
439 unsigned short scsi_sg_tablesize;
440 unsigned short pages_per_mr;
441 bool snd_w_inv;
442 };
443
444 /**
445 * struct iscsi_iser_task - iser task context
446 *
447 * @desc: TX descriptor
448 * @iser_conn: link to iser connection
449 * @status: current task status
450 * @sc: link to scsi command
451 * @command_sent: indicate if command was sent
452 * @dir: iser data direction
453 * @rdma_reg: task rdma registration desc
454 * @data: iser data buffer desc
455 * @prot: iser protection buffer desc
456 */
457 struct iscsi_iser_task {
458 struct iser_tx_desc desc;
459 struct iser_conn *iser_conn;
460 enum iser_task_status status;
461 struct scsi_cmnd *sc;
462 int command_sent;
463 int dir[ISER_DIRS_NUM];
464 struct iser_mem_reg rdma_reg[ISER_DIRS_NUM];
465 struct iser_data_buf data[ISER_DIRS_NUM];
466 struct iser_data_buf prot[ISER_DIRS_NUM];
467 };
468
469 /**
470 * struct iser_global - iSER global context
471 *
472 * @device_list_mutex: protects device_list
473 * @device_list: iser devices global list
474 * @connlist_mutex: protects connlist
475 * @connlist: iser connections global list
476 * @desc_cache: kmem cache for tx dataout
477 */
478 struct iser_global {
479 struct mutex device_list_mutex;
480 struct list_head device_list;
481 struct mutex connlist_mutex;
482 struct list_head connlist;
483 struct kmem_cache *desc_cache;
484 };
485
486 extern struct iser_global ig;
487 extern int iser_debug_level;
488 extern bool iser_pi_enable;
489 extern int iser_pi_guard;
490 extern unsigned int iser_max_sectors;
491 extern bool iser_always_reg;
492
493 int iser_send_control(struct iscsi_conn *conn,
494 struct iscsi_task *task);
495
496 int iser_send_command(struct iscsi_conn *conn,
497 struct iscsi_task *task);
498
499 int iser_send_data_out(struct iscsi_conn *conn,
500 struct iscsi_task *task,
501 struct iscsi_data *hdr);
502
503 void iscsi_iser_recv(struct iscsi_conn *conn,
504 struct iscsi_hdr *hdr,
505 char *rx_data,
506 int rx_data_len);
507
508 void iser_conn_init(struct iser_conn *iser_conn);
509
510 void iser_conn_release(struct iser_conn *iser_conn);
511
512 int iser_conn_terminate(struct iser_conn *iser_conn);
513
514 void iser_release_work(struct work_struct *work);
515
516 void iser_err_comp(struct ib_wc *wc, const char *type);
517 void iser_login_rsp(struct ib_cq *cq, struct ib_wc *wc);
518 void iser_task_rsp(struct ib_cq *cq, struct ib_wc *wc);
519 void iser_cmd_comp(struct ib_cq *cq, struct ib_wc *wc);
520 void iser_ctrl_comp(struct ib_cq *cq, struct ib_wc *wc);
521 void iser_dataout_comp(struct ib_cq *cq, struct ib_wc *wc);
522 void iser_reg_comp(struct ib_cq *cq, struct ib_wc *wc);
523
524 void iser_task_rdma_init(struct iscsi_iser_task *task);
525
526 void iser_task_rdma_finalize(struct iscsi_iser_task *task);
527
528 void iser_free_rx_descriptors(struct iser_conn *iser_conn);
529
530 void iser_finalize_rdma_unaligned_sg(struct iscsi_iser_task *iser_task,
531 struct iser_data_buf *mem,
532 enum iser_data_dir cmd_dir);
533
534 int iser_reg_mem_fastreg(struct iscsi_iser_task *task,
535 enum iser_data_dir dir,
536 bool all_imm);
537 void iser_unreg_mem_fastreg(struct iscsi_iser_task *task,
538 enum iser_data_dir dir);
539
540 int iser_connect(struct iser_conn *iser_conn,
541 struct sockaddr *src_addr,
542 struct sockaddr *dst_addr,
543 int non_blocking);
544
545 int iser_post_recvl(struct iser_conn *iser_conn);
546 int iser_post_recvm(struct iser_conn *iser_conn, int count);
547 int iser_post_send(struct ib_conn *ib_conn, struct iser_tx_desc *tx_desc,
548 bool signal);
549
550 int iser_dma_map_task_data(struct iscsi_iser_task *iser_task,
551 struct iser_data_buf *data,
552 enum iser_data_dir iser_dir,
553 enum dma_data_direction dma_dir);
554
555 void iser_dma_unmap_task_data(struct iscsi_iser_task *iser_task,
556 struct iser_data_buf *data,
557 enum dma_data_direction dir);
558
559 int iser_initialize_task_headers(struct iscsi_task *task,
560 struct iser_tx_desc *tx_desc);
561 int iser_alloc_rx_descriptors(struct iser_conn *iser_conn,
562 struct iscsi_session *session);
563 int iser_alloc_fastreg_pool(struct ib_conn *ib_conn,
564 unsigned cmds_max,
565 unsigned int size);
566 void iser_free_fastreg_pool(struct ib_conn *ib_conn);
567 u8 iser_check_task_pi_status(struct iscsi_iser_task *iser_task,
568 enum iser_data_dir cmd_dir, sector_t *sector);
569
570 static inline struct iser_conn *
to_iser_conn(struct ib_conn * ib_conn)571 to_iser_conn(struct ib_conn *ib_conn)
572 {
573 return container_of(ib_conn, struct iser_conn, ib_conn);
574 }
575
576 static inline struct iser_rx_desc *
iser_rx(struct ib_cqe * cqe)577 iser_rx(struct ib_cqe *cqe)
578 {
579 return container_of(cqe, struct iser_rx_desc, cqe);
580 }
581
582 static inline struct iser_tx_desc *
iser_tx(struct ib_cqe * cqe)583 iser_tx(struct ib_cqe *cqe)
584 {
585 return container_of(cqe, struct iser_tx_desc, cqe);
586 }
587
588 static inline struct iser_login_desc *
iser_login(struct ib_cqe * cqe)589 iser_login(struct ib_cqe *cqe)
590 {
591 return container_of(cqe, struct iser_login_desc, cqe);
592 }
593
594 #endif
595