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
52#include <linux/interrupt.h>
53#include <linux/wait.h>
54#include <linux/sched.h>
55#include <linux/list.h>
56#include <linux/slab.h>
57#include <linux/dma-mapping.h>
58#include <linux/mutex.h>
59#include <linux/mempool.h>
60#include <linux/uio.h>
61
62#include <linux/socket.h>
63#include <linux/in.h>
64#include <linux/in6.h>
65
66#include <rdma/ib_verbs.h>
67#include <rdma/ib_fmr_pool.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#define SHIFT_4K	12
99#define SIZE_4K	(1ULL << SHIFT_4K)
100#define MASK_4K	(~(SIZE_4K-1))
101					/* support up to 512KB in one RDMA */
102#define ISCSI_ISER_SG_TABLESIZE         (0x80000 >> SHIFT_4K)
103#define ISER_DEF_XMIT_CMDS_DEFAULT		512
104#if ISCSI_DEF_XMIT_CMDS_MAX > ISER_DEF_XMIT_CMDS_DEFAULT
105	#define ISER_DEF_XMIT_CMDS_MAX		ISCSI_DEF_XMIT_CMDS_MAX
106#else
107	#define ISER_DEF_XMIT_CMDS_MAX		ISER_DEF_XMIT_CMDS_DEFAULT
108#endif
109#define ISER_DEF_CMD_PER_LUN		ISER_DEF_XMIT_CMDS_MAX
110
111/* QP settings */
112/* Maximal bounds on received asynchronous PDUs */
113#define ISER_MAX_RX_MISC_PDUS		4 /* NOOP_IN(2) , ASYNC_EVENT(2)   */
114
115#define ISER_MAX_TX_MISC_PDUS		6 /* NOOP_OUT(2), TEXT(1),         *
116					   * SCSI_TMFUNC(2), LOGOUT(1) */
117
118#define ISER_QP_MAX_RECV_DTOS		(ISER_DEF_XMIT_CMDS_MAX)
119
120#define ISER_MIN_POSTED_RX		(ISER_DEF_XMIT_CMDS_MAX >> 2)
121
122/* the max TX (send) WR supported by the iSER QP is defined by                 *
123 * max_send_wr = T * (1 + D) + C ; D is how many inflight dataouts we expect   *
124 * to have at max for SCSI command. The tx posting & completion handling code  *
125 * supports -EAGAIN scheme where tx is suspended till the QP has room for more *
126 * send WR. D=8 comes from 64K/8K                                              */
127
128#define ISER_INFLIGHT_DATAOUTS		8
129
130#define ISER_QP_MAX_REQ_DTOS		(ISER_DEF_XMIT_CMDS_MAX *    \
131					(1 + ISER_INFLIGHT_DATAOUTS) + \
132					ISER_MAX_TX_MISC_PDUS        + \
133					ISER_MAX_RX_MISC_PDUS)
134
135/* Max registration work requests per command */
136#define ISER_MAX_REG_WR_PER_CMD		5
137
138/* For Signature we don't support DATAOUTs so no need to make room for them */
139#define ISER_QP_SIG_MAX_REQ_DTOS	(ISER_DEF_XMIT_CMDS_MAX	*       \
140					(1 + ISER_MAX_REG_WR_PER_CMD) + \
141					ISER_MAX_TX_MISC_PDUS         + \
142					ISER_MAX_RX_MISC_PDUS)
143
144#define ISER_GET_MAX_XMIT_CMDS(send_wr) ((send_wr			\
145					 - ISER_MAX_TX_MISC_PDUS	\
146					 - ISER_MAX_RX_MISC_PDUS) /	\
147					 (1 + ISER_INFLIGHT_DATAOUTS))
148
149#define ISER_WC_BATCH_COUNT   16
150#define ISER_SIGNAL_CMD_COUNT 32
151
152#define ISER_VER			0x10
153#define ISER_WSV			0x08
154#define ISER_RSV			0x04
155
156#define ISER_FASTREG_LI_WRID		0xffffffffffffffffULL
157#define ISER_BEACON_WRID		0xfffffffffffffffeULL
158
159/**
160 * struct iser_hdr - iSER header
161 *
162 * @flags:        flags support (zbva, remote_inv)
163 * @rsvd:         reserved
164 * @write_stag:   write rkey
165 * @write_va:     write virtual address
166 * @reaf_stag:    read rkey
167 * @read_va:      read virtual address
168 */
169struct iser_hdr {
170	u8      flags;
171	u8      rsvd[3];
172	__be32  write_stag;
173	__be64  write_va;
174	__be32  read_stag;
175	__be64  read_va;
176} __attribute__((packed));
177
178
179#define ISER_ZBVA_NOT_SUPPORTED		0x80
180#define ISER_SEND_W_INV_NOT_SUPPORTED	0x40
181
182struct iser_cm_hdr {
183	u8      flags;
184	u8      rsvd[3];
185} __packed;
186
187/* Constant PDU lengths calculations */
188#define ISER_HEADERS_LEN  (sizeof(struct iser_hdr) + sizeof(struct iscsi_hdr))
189
190#define ISER_RECV_DATA_SEG_LEN	128
191#define ISER_RX_PAYLOAD_SIZE	(ISER_HEADERS_LEN + ISER_RECV_DATA_SEG_LEN)
192#define ISER_RX_LOGIN_SIZE	(ISER_HEADERS_LEN + ISCSI_DEF_MAX_RECV_SEG_LEN)
193
194/* Length of an object name string */
195#define ISER_OBJECT_NAME_SIZE		    64
196
197enum iser_conn_state {
198	ISER_CONN_INIT,		   /* descriptor allocd, no conn          */
199	ISER_CONN_PENDING,	   /* in the process of being established */
200	ISER_CONN_UP,		   /* up and running                      */
201	ISER_CONN_TERMINATING,	   /* in the process of being terminated  */
202	ISER_CONN_DOWN,		   /* shut down                           */
203	ISER_CONN_STATES_NUM
204};
205
206enum iser_task_status {
207	ISER_TASK_STATUS_INIT = 0,
208	ISER_TASK_STATUS_STARTED,
209	ISER_TASK_STATUS_COMPLETED
210};
211
212enum iser_data_dir {
213	ISER_DIR_IN = 0,	   /* to initiator */
214	ISER_DIR_OUT,		   /* from initiator */
215	ISER_DIRS_NUM
216};
217
218/**
219 * struct iser_data_buf - iSER data buffer
220 *
221 * @sg:           pointer to the sg list
222 * @size:         num entries of this sg
223 * @data_len:     total beffer byte len
224 * @dma_nents:    returned by dma_map_sg
225 * @orig_sg:      pointer to the original sg list (in case
226 *                we used a copy)
227 * @orig_size:    num entris of orig sg list
228 */
229struct iser_data_buf {
230	struct scatterlist *sg;
231	unsigned int       size;
232	unsigned long      data_len;
233	unsigned int       dma_nents;
234	struct scatterlist *orig_sg;
235	unsigned int       orig_size;
236  };
237
238/* fwd declarations */
239struct iser_device;
240struct iscsi_iser_task;
241struct iscsi_endpoint;
242
243/**
244 * struct iser_mem_reg - iSER memory registration info
245 *
246 * @sge:          memory region sg element
247 * @rkey:         memory region remote key
248 * @mem_h:        pointer to registration context (FMR/Fastreg)
249 */
250struct iser_mem_reg {
251	struct ib_sge	 sge;
252	u32		 rkey;
253	void		*mem_h;
254};
255
256enum iser_desc_type {
257	ISCSI_TX_CONTROL ,
258	ISCSI_TX_SCSI_COMMAND,
259	ISCSI_TX_DATAOUT
260};
261
262/**
263 * struct iser_tx_desc - iSER TX descriptor (for send wr_id)
264 *
265 * @iser_header:   iser header
266 * @iscsi_header:  iscsi header
267 * @type:          command/control/dataout
268 * @dam_addr:      header buffer dma_address
269 * @tx_sg:         sg[0] points to iser/iscsi headers
270 *                 sg[1] optionally points to either of immediate data
271 *                 unsolicited data-out or control
272 * @num_sge:       number sges used on this TX task
273 * @mapped:        Is the task header mapped
274 */
275struct iser_tx_desc {
276	struct iser_hdr              iser_header;
277	struct iscsi_hdr             iscsi_header;
278	enum   iser_desc_type        type;
279	u64		             dma_addr;
280	struct ib_sge		     tx_sg[2];
281	int                          num_sge;
282	bool			     mapped;
283};
284
285#define ISER_RX_PAD_SIZE	(256 - (ISER_RX_PAYLOAD_SIZE + \
286					sizeof(u64) + sizeof(struct ib_sge)))
287/**
288 * struct iser_rx_desc - iSER RX descriptor (for recv wr_id)
289 *
290 * @iser_header:   iser header
291 * @iscsi_header:  iscsi header
292 * @data:          received data segment
293 * @dma_addr:      receive buffer dma address
294 * @rx_sg:         ib_sge of receive buffer
295 * @pad:           for sense data TODO: Modify to maximum sense length supported
296 */
297struct iser_rx_desc {
298	struct iser_hdr              iser_header;
299	struct iscsi_hdr             iscsi_header;
300	char		             data[ISER_RECV_DATA_SEG_LEN];
301	u64		             dma_addr;
302	struct ib_sge		     rx_sg;
303	char		             pad[ISER_RX_PAD_SIZE];
304} __attribute__((packed));
305
306struct iser_conn;
307struct ib_conn;
308struct iscsi_iser_task;
309
310/**
311 * struct iser_comp - iSER completion context
312 *
313 * @device:     pointer to device handle
314 * @cq:         completion queue
315 * @wcs:        work completion array
316 * @tasklet:    Tasklet handle
317 * @active_qps: Number of active QPs attached
318 *              to completion context
319 */
320struct iser_comp {
321	struct iser_device      *device;
322	struct ib_cq		*cq;
323	struct ib_wc		 wcs[ISER_WC_BATCH_COUNT];
324	struct tasklet_struct	 tasklet;
325	int                      active_qps;
326};
327
328/**
329 * struct iser_device - iSER device handle
330 *
331 * @ib_device:     RDMA device
332 * @pd:            Protection Domain for this device
333 * @dev_attr:      Device attributes container
334 * @mr:            Global DMA memory region
335 * @event_handler: IB events handle routine
336 * @ig_list:	   entry in devices list
337 * @refcount:      Reference counter, dominated by open iser connections
338 * @comps_used:    Number of completion contexts used, Min between online
339 *                 cpus and device max completion vectors
340 * @comps:         Dinamically allocated array of completion handlers
341 * Memory registration pool Function pointers (FMR or Fastreg):
342 *     @iser_alloc_rdma_reg_res: Allocation of memory regions pool
343 *     @iser_free_rdma_reg_res:  Free of memory regions pool
344 *     @iser_reg_rdma_mem:       Memory registration routine
345 *     @iser_unreg_rdma_mem:     Memory deregistration routine
346 */
347struct iser_device {
348	struct ib_device             *ib_device;
349	struct ib_pd	             *pd;
350	struct ib_device_attr	     dev_attr;
351	struct ib_mr	             *mr;
352	struct ib_event_handler      event_handler;
353	struct list_head             ig_list;
354	int                          refcount;
355	int			     comps_used;
356	struct iser_comp	     *comps;
357	int                          (*iser_alloc_rdma_reg_res)(struct ib_conn *ib_conn,
358								unsigned cmds_max);
359	void                         (*iser_free_rdma_reg_res)(struct ib_conn *ib_conn);
360	int                          (*iser_reg_rdma_mem)(struct iscsi_iser_task *iser_task,
361							  enum iser_data_dir cmd_dir);
362	void                         (*iser_unreg_rdma_mem)(struct iscsi_iser_task *iser_task,
363							    enum iser_data_dir cmd_dir);
364};
365
366#define ISER_CHECK_GUARD	0xc0
367#define ISER_CHECK_REFTAG	0x0f
368#define ISER_CHECK_APPTAG	0x30
369
370enum iser_reg_indicator {
371	ISER_DATA_KEY_VALID	= 1 << 0,
372	ISER_PROT_KEY_VALID	= 1 << 1,
373	ISER_SIG_KEY_VALID	= 1 << 2,
374	ISER_FASTREG_PROTECTED	= 1 << 3,
375};
376
377/**
378 * struct iser_pi_context - Protection information context
379 *
380 * @prot_mr:        protection memory region
381 * @prot_frpl:      protection fastreg page list
382 * @sig_mr:         signature feature enabled memory region
383 */
384struct iser_pi_context {
385	struct ib_mr                   *prot_mr;
386	struct ib_fast_reg_page_list   *prot_frpl;
387	struct ib_mr                   *sig_mr;
388};
389
390/**
391 * struct fast_reg_descriptor - Fast registration descriptor
392 *
393 * @list:           entry in connection fastreg pool
394 * @data_mr:        data memory region
395 * @data_frpl:      data fastreg page list
396 * @pi_ctx:         protection information context
397 * @reg_indicators: fast registration indicators
398 */
399struct fast_reg_descriptor {
400	struct list_head		  list;
401	struct ib_mr			 *data_mr;
402	struct ib_fast_reg_page_list     *data_frpl;
403	struct iser_pi_context		 *pi_ctx;
404	u8				  reg_indicators;
405};
406
407/**
408 * struct ib_conn - Infiniband related objects
409 *
410 * @cma_id:              rdma_cm connection maneger handle
411 * @qp:                  Connection Queue-pair
412 * @post_recv_buf_count: post receive counter
413 * @sig_count:           send work request signal count
414 * @rx_wr:               receive work request for batch posts
415 * @device:              reference to iser device
416 * @comp:                iser completion context
417 * @pi_support:          Indicate device T10-PI support
418 * @beacon:              beacon send wr to signal all flush errors were drained
419 * @flush_comp:          completes when all connection completions consumed
420 * @lock:                protects fmr/fastreg pool
421 * @union.fmr:
422 *     @pool:            FMR pool for fast registrations
423 *     @page_vec:        page vector to hold mapped commands pages
424 *                       used for registration
425 * @union.fastreg:
426 *     @pool:            Fast registration descriptors pool for fast
427 *                       registrations
428 *     @pool_size:       Size of pool
429 */
430struct ib_conn {
431	struct rdma_cm_id           *cma_id;
432	struct ib_qp	            *qp;
433	int                          post_recv_buf_count;
434	u8                           sig_count;
435	struct ib_recv_wr	     rx_wr[ISER_MIN_POSTED_RX];
436	struct iser_device          *device;
437	struct iser_comp	    *comp;
438	bool			     pi_support;
439	struct ib_send_wr	     beacon;
440	struct completion	     flush_comp;
441	spinlock_t		     lock;
442	union {
443		struct {
444			struct ib_fmr_pool      *pool;
445			struct iser_page_vec	*page_vec;
446		} fmr;
447		struct {
448			struct list_head	 pool;
449			int			 pool_size;
450		} fastreg;
451	};
452};
453
454/**
455 * struct iser_conn - iSER connection context
456 *
457 * @ib_conn:          connection RDMA resources
458 * @iscsi_conn:       link to matching iscsi connection
459 * @ep:               transport handle
460 * @state:            connection logical state
461 * @qp_max_recv_dtos: maximum number of data outs, corresponds
462 *                    to max number of post recvs
463 * @qp_max_recv_dtos_mask: (qp_max_recv_dtos - 1)
464 * @min_posted_rx:    (qp_max_recv_dtos >> 2)
465 * @max_cmds:         maximum cmds allowed for this connection
466 * @name:             connection peer portal
467 * @release_work:     deffered work for release job
468 * @state_mutex:      protects iser onnection state
469 * @stop_completion:  conn_stop completion
470 * @ib_completion:    RDMA cleanup completion
471 * @up_completion:    connection establishment completed
472 *                    (state is ISER_CONN_UP)
473 * @conn_list:        entry in ig conn list
474 * @login_buf:        login data buffer (stores login parameters)
475 * @login_req_buf:    login request buffer
476 * @login_req_dma:    login request buffer dma address
477 * @login_resp_buf:   login response buffer
478 * @login_resp_dma:   login response buffer dma address
479 * @rx_desc_head:     head of rx_descs cyclic buffer
480 * @rx_descs:         rx buffers array (cyclic buffer)
481 * @num_rx_descs:     number of rx descriptors
482 */
483struct iser_conn {
484	struct ib_conn		     ib_conn;
485	struct iscsi_conn	     *iscsi_conn;
486	struct iscsi_endpoint	     *ep;
487	enum iser_conn_state	     state;
488	unsigned		     qp_max_recv_dtos;
489	unsigned		     qp_max_recv_dtos_mask;
490	unsigned		     min_posted_rx;
491	u16                          max_cmds;
492	char 			     name[ISER_OBJECT_NAME_SIZE];
493	struct work_struct	     release_work;
494	struct mutex		     state_mutex;
495	struct completion	     stop_completion;
496	struct completion	     ib_completion;
497	struct completion	     up_completion;
498	struct list_head	     conn_list;
499
500	char  			     *login_buf;
501	char			     *login_req_buf, *login_resp_buf;
502	u64			     login_req_dma, login_resp_dma;
503	unsigned int 		     rx_desc_head;
504	struct iser_rx_desc	     *rx_descs;
505	u32                          num_rx_descs;
506};
507
508/**
509 * struct iscsi_iser_task - iser task context
510 *
511 * @desc:     TX descriptor
512 * @iser_conn:        link to iser connection
513 * @status:           current task status
514 * @sc:               link to scsi command
515 * @command_sent:     indicate if command was sent
516 * @dir:              iser data direction
517 * @rdma_reg:         task rdma registration desc
518 * @data:             iser data buffer desc
519 * @prot:             iser protection buffer desc
520 */
521struct iscsi_iser_task {
522	struct iser_tx_desc          desc;
523	struct iser_conn	     *iser_conn;
524	enum iser_task_status 	     status;
525	struct scsi_cmnd	     *sc;
526	int                          command_sent;
527	int                          dir[ISER_DIRS_NUM];
528	struct iser_mem_reg          rdma_reg[ISER_DIRS_NUM];
529	struct iser_data_buf         data[ISER_DIRS_NUM];
530	struct iser_data_buf         prot[ISER_DIRS_NUM];
531};
532
533struct iser_page_vec {
534	u64 *pages;
535	int length;
536	int offset;
537	int data_size;
538};
539
540/**
541 * struct iser_global: iSER global context
542 *
543 * @device_list_mutex:    protects device_list
544 * @device_list:          iser devices global list
545 * @connlist_mutex:       protects connlist
546 * @connlist:             iser connections global list
547 * @desc_cache:           kmem cache for tx dataout
548 */
549struct iser_global {
550	struct mutex      device_list_mutex;
551	struct list_head  device_list;
552	struct mutex      connlist_mutex;
553	struct list_head  connlist;
554	struct kmem_cache *desc_cache;
555};
556
557extern struct iser_global ig;
558extern int iser_debug_level;
559extern bool iser_pi_enable;
560extern int iser_pi_guard;
561
562int iser_send_control(struct iscsi_conn *conn,
563		      struct iscsi_task *task);
564
565int iser_send_command(struct iscsi_conn *conn,
566		      struct iscsi_task *task);
567
568int iser_send_data_out(struct iscsi_conn *conn,
569		       struct iscsi_task *task,
570		       struct iscsi_data *hdr);
571
572void iscsi_iser_recv(struct iscsi_conn *conn,
573		     struct iscsi_hdr *hdr,
574		     char *rx_data,
575		     int rx_data_len);
576
577void iser_conn_init(struct iser_conn *iser_conn);
578
579void iser_conn_release(struct iser_conn *iser_conn);
580
581int iser_conn_terminate(struct iser_conn *iser_conn);
582
583void iser_release_work(struct work_struct *work);
584
585void iser_rcv_completion(struct iser_rx_desc *desc,
586			 unsigned long dto_xfer_len,
587			 struct ib_conn *ib_conn);
588
589void iser_snd_completion(struct iser_tx_desc *desc,
590			 struct ib_conn *ib_conn);
591
592void iser_task_rdma_init(struct iscsi_iser_task *task);
593
594void iser_task_rdma_finalize(struct iscsi_iser_task *task);
595
596void iser_free_rx_descriptors(struct iser_conn *iser_conn);
597
598void iser_finalize_rdma_unaligned_sg(struct iscsi_iser_task *iser_task,
599				     struct iser_data_buf *mem,
600				     enum iser_data_dir cmd_dir);
601
602int  iser_reg_rdma_mem_fmr(struct iscsi_iser_task *task,
603			   enum iser_data_dir cmd_dir);
604int  iser_reg_rdma_mem_fastreg(struct iscsi_iser_task *task,
605			       enum iser_data_dir cmd_dir);
606
607int  iser_connect(struct iser_conn *iser_conn,
608		  struct sockaddr *src_addr,
609		  struct sockaddr *dst_addr,
610		  int non_blocking);
611
612void iser_unreg_mem_fmr(struct iscsi_iser_task *iser_task,
613			enum iser_data_dir cmd_dir);
614void iser_unreg_mem_fastreg(struct iscsi_iser_task *iser_task,
615			    enum iser_data_dir cmd_dir);
616
617int  iser_post_recvl(struct iser_conn *iser_conn);
618int  iser_post_recvm(struct iser_conn *iser_conn, int count);
619int  iser_post_send(struct ib_conn *ib_conn, struct iser_tx_desc *tx_desc,
620		    bool signal);
621
622int iser_dma_map_task_data(struct iscsi_iser_task *iser_task,
623			   struct iser_data_buf *data,
624			   enum iser_data_dir iser_dir,
625			   enum dma_data_direction dma_dir);
626
627void iser_dma_unmap_task_data(struct iscsi_iser_task *iser_task,
628			      struct iser_data_buf *data,
629			      enum dma_data_direction dir);
630
631int  iser_initialize_task_headers(struct iscsi_task *task,
632			struct iser_tx_desc *tx_desc);
633int iser_alloc_rx_descriptors(struct iser_conn *iser_conn,
634			      struct iscsi_session *session);
635int iser_create_fmr_pool(struct ib_conn *ib_conn, unsigned cmds_max);
636void iser_free_fmr_pool(struct ib_conn *ib_conn);
637int iser_create_fastreg_pool(struct ib_conn *ib_conn, unsigned cmds_max);
638void iser_free_fastreg_pool(struct ib_conn *ib_conn);
639u8 iser_check_task_pi_status(struct iscsi_iser_task *iser_task,
640			     enum iser_data_dir cmd_dir, sector_t *sector);
641struct fast_reg_descriptor *
642iser_reg_desc_get(struct ib_conn *ib_conn);
643void
644iser_reg_desc_put(struct ib_conn *ib_conn,
645		  struct fast_reg_descriptor *desc);
646#endif
647