xref: /openbmc/linux/drivers/scsi/cxgbi/libcxgbi.h (revision 4f3db074)
1 /*
2  * libcxgbi.h: Chelsio common library for T3/T4 iSCSI driver.
3  *
4  * Copyright (c) 2010 Chelsio Communications, Inc.
5  *
6  * This program is free software; you can redistribute it and/or modify
7  * it under the terms of the GNU General Public License as published by
8  * the Free Software Foundation.
9  *
10  * Written by: Karen Xie (kxie@chelsio.com)
11  * Written by: Rakesh Ranjan (rranjan@chelsio.com)
12  */
13 
14 #ifndef	__LIBCXGBI_H__
15 #define	__LIBCXGBI_H__
16 
17 #include <linux/kernel.h>
18 #include <linux/errno.h>
19 #include <linux/types.h>
20 #include <linux/debugfs.h>
21 #include <linux/list.h>
22 #include <linux/netdevice.h>
23 #include <linux/if_vlan.h>
24 #include <linux/scatterlist.h>
25 #include <linux/skbuff.h>
26 #include <linux/vmalloc.h>
27 #include <scsi/scsi_device.h>
28 #include <scsi/libiscsi_tcp.h>
29 
30 enum cxgbi_dbg_flag {
31 	CXGBI_DBG_ISCSI,
32 	CXGBI_DBG_DDP,
33 	CXGBI_DBG_TOE,
34 	CXGBI_DBG_SOCK,
35 
36 	CXGBI_DBG_PDU_TX,
37 	CXGBI_DBG_PDU_RX,
38 	CXGBI_DBG_DEV,
39 };
40 
41 #define log_debug(level, fmt, ...)	\
42 	do {	\
43 		if (dbg_level & (level)) \
44 			pr_info(fmt, ##__VA_ARGS__); \
45 	} while (0)
46 
47 #define pr_info_ipaddr(fmt_trail,					\
48 			addr1, addr2, args_trail...)			\
49 do {									\
50 	if (!((1 << CXGBI_DBG_SOCK) & dbg_level))			\
51 		break;							\
52 	pr_info("%pISpc - %pISpc, " fmt_trail,				\
53 		addr1, addr2, args_trail);				\
54 } while (0)
55 
56 /* max. connections per adapter */
57 #define CXGBI_MAX_CONN		16384
58 
59 /* always allocate rooms for AHS */
60 #define SKB_TX_ISCSI_PDU_HEADER_MAX	\
61 	(sizeof(struct iscsi_hdr) + ISCSI_MAX_AHS_SIZE)
62 
63 #define	ISCSI_PDU_NONPAYLOAD_LEN	312 /* bhs(48) + ahs(256) + digest(8)*/
64 
65 /*
66  * align pdu size to multiple of 512 for better performance
67  */
68 #define cxgbi_align_pdu_size(n) do { n = (n) & (~511); } while (0)
69 
70 #define ULP2_MODE_ISCSI		2
71 
72 #define ULP2_MAX_PKT_SIZE	16224
73 #define ULP2_MAX_PDU_PAYLOAD	\
74 	(ULP2_MAX_PKT_SIZE - ISCSI_PDU_NONPAYLOAD_LEN)
75 
76 /*
77  * For iscsi connections HW may inserts digest bytes into the pdu. Those digest
78  * bytes are not sent by the host but are part of the TCP payload and therefore
79  * consume TCP sequence space.
80  */
81 static const unsigned int ulp2_extra_len[] = { 0, 4, 4, 8 };
82 static inline unsigned int cxgbi_ulp_extra_len(int submode)
83 {
84 	return ulp2_extra_len[submode & 3];
85 }
86 
87 /*
88  * struct pagepod_hdr, pagepod - pagepod format
89  */
90 
91 #define CPL_RX_DDP_STATUS_DDP_SHIFT	16 /* ddp'able */
92 #define CPL_RX_DDP_STATUS_PAD_SHIFT	19 /* pad error */
93 #define CPL_RX_DDP_STATUS_HCRC_SHIFT	20 /* hcrc error */
94 #define CPL_RX_DDP_STATUS_DCRC_SHIFT	21 /* dcrc error */
95 
96 struct cxgbi_pagepod_hdr {
97 	u32 vld_tid;
98 	u32 pgsz_tag_clr;
99 	u32 max_offset;
100 	u32 page_offset;
101 	u64 rsvd;
102 };
103 
104 #define PPOD_PAGES_MAX			4
105 struct cxgbi_pagepod {
106 	struct cxgbi_pagepod_hdr hdr;
107 	u64 addr[PPOD_PAGES_MAX + 1];
108 };
109 
110 struct cxgbi_tag_format {
111 	unsigned char sw_bits;
112 	unsigned char rsvd_bits;
113 	unsigned char rsvd_shift;
114 	unsigned char filler[1];
115 	u32 rsvd_mask;
116 };
117 
118 struct cxgbi_gather_list {
119 	unsigned int tag;
120 	unsigned int length;
121 	unsigned int offset;
122 	unsigned int nelem;
123 	struct page **pages;
124 	dma_addr_t phys_addr[0];
125 };
126 
127 struct cxgbi_ddp_info {
128 	struct kref refcnt;
129 	struct cxgbi_device *cdev;
130 	struct pci_dev *pdev;
131 	unsigned int max_txsz;
132 	unsigned int max_rxsz;
133 	unsigned int llimit;
134 	unsigned int ulimit;
135 	unsigned int nppods;
136 	unsigned int idx_last;
137 	unsigned char idx_bits;
138 	unsigned char filler[3];
139 	unsigned int idx_mask;
140 	unsigned int rsvd_tag_mask;
141 	spinlock_t map_lock;
142 	struct cxgbi_gather_list **gl_map;
143 };
144 
145 #define DDP_PGIDX_MAX		4
146 #define DDP_THRESHOLD		2048
147 
148 #define PPOD_PAGES_SHIFT	2       /*  4 pages per pod */
149 
150 #define PPOD_SIZE               sizeof(struct cxgbi_pagepod)  /*  64 */
151 #define PPOD_SIZE_SHIFT         6
152 
153 #define ULPMEM_DSGL_MAX_NPPODS	16	/*  1024/PPOD_SIZE */
154 #define ULPMEM_IDATA_MAX_NPPODS	4	/*  256/PPOD_SIZE */
155 #define PCIE_MEMWIN_MAX_NPPODS	16	/*  1024/PPOD_SIZE */
156 
157 #define PPOD_COLOR_SHIFT	0
158 #define PPOD_COLOR(x)		((x) << PPOD_COLOR_SHIFT)
159 
160 #define PPOD_IDX_SHIFT          6
161 #define PPOD_IDX_MAX_SIZE       24
162 
163 #define PPOD_TID_SHIFT		0
164 #define PPOD_TID(x)		((x) << PPOD_TID_SHIFT)
165 
166 #define PPOD_TAG_SHIFT		6
167 #define PPOD_TAG(x)		((x) << PPOD_TAG_SHIFT)
168 
169 #define PPOD_VALID_SHIFT	24
170 #define PPOD_VALID(x)		((x) << PPOD_VALID_SHIFT)
171 #define PPOD_VALID_FLAG		PPOD_VALID(1U)
172 
173 /*
174  * sge_opaque_hdr -
175  * Opaque version of structure the SGE stores at skb->head of TX_DATA packets
176  * and for which we must reserve space.
177  */
178 struct sge_opaque_hdr {
179 	void *dev;
180 	dma_addr_t addr[MAX_SKB_FRAGS + 1];
181 };
182 
183 struct cxgbi_sock {
184 	struct cxgbi_device *cdev;
185 
186 	int tid;
187 	int atid;
188 	unsigned long flags;
189 	unsigned int mtu;
190 	unsigned short rss_qid;
191 	unsigned short txq_idx;
192 	unsigned short advmss;
193 	unsigned int tx_chan;
194 	unsigned int rx_chan;
195 	unsigned int mss_idx;
196 	unsigned int smac_idx;
197 	unsigned char port_id;
198 	int wr_max_cred;
199 	int wr_cred;
200 	int wr_una_cred;
201 	unsigned char hcrc_len;
202 	unsigned char dcrc_len;
203 
204 	void *l2t;
205 	struct sk_buff *wr_pending_head;
206 	struct sk_buff *wr_pending_tail;
207 	struct sk_buff *cpl_close;
208 	struct sk_buff *cpl_abort_req;
209 	struct sk_buff *cpl_abort_rpl;
210 	struct sk_buff *skb_ulp_lhdr;
211 	spinlock_t lock;
212 	struct kref refcnt;
213 	unsigned int state;
214 	unsigned int csk_family;
215 	union {
216 		struct sockaddr_in saddr;
217 		struct sockaddr_in6 saddr6;
218 	};
219 	union {
220 		struct sockaddr_in daddr;
221 		struct sockaddr_in6 daddr6;
222 	};
223 	struct dst_entry *dst;
224 	struct sk_buff_head receive_queue;
225 	struct sk_buff_head write_queue;
226 	struct timer_list retry_timer;
227 	int err;
228 	rwlock_t callback_lock;
229 	void *user_data;
230 
231 	u32 rcv_nxt;
232 	u32 copied_seq;
233 	u32 rcv_wup;
234 	u32 snd_nxt;
235 	u32 snd_una;
236 	u32 write_seq;
237 };
238 
239 /*
240  * connection states
241  */
242 enum cxgbi_sock_states{
243 	CTP_CLOSED,
244 	CTP_CONNECTING,
245 	CTP_ACTIVE_OPEN,
246 	CTP_ESTABLISHED,
247 	CTP_ACTIVE_CLOSE,
248 	CTP_PASSIVE_CLOSE,
249 	CTP_CLOSE_WAIT_1,
250 	CTP_CLOSE_WAIT_2,
251 	CTP_ABORTING,
252 };
253 
254 /*
255  * Connection flags -- many to track some close related events.
256  */
257 enum cxgbi_sock_flags {
258 	CTPF_ABORT_RPL_RCVD,	/*received one ABORT_RPL_RSS message */
259 	CTPF_ABORT_REQ_RCVD,	/*received one ABORT_REQ_RSS message */
260 	CTPF_ABORT_RPL_PENDING,	/* expecting an abort reply */
261 	CTPF_TX_DATA_SENT,	/* already sent a TX_DATA WR */
262 	CTPF_ACTIVE_CLOSE_NEEDED,/* need to be closed */
263 	CTPF_HAS_ATID,		/* reserved atid */
264 	CTPF_HAS_TID,		/* reserved hw tid */
265 	CTPF_OFFLOAD_DOWN,	/* offload function off */
266 };
267 
268 struct cxgbi_skb_rx_cb {
269 	__u32 ddigest;
270 	__u32 pdulen;
271 };
272 
273 struct cxgbi_skb_tx_cb {
274 	void *l2t;
275 	struct sk_buff *wr_next;
276 };
277 
278 enum cxgbi_skcb_flags {
279 	SKCBF_TX_NEED_HDR,	/* packet needs a header */
280 	SKCBF_RX_COALESCED,	/* received whole pdu */
281 	SKCBF_RX_HDR,		/* received pdu header */
282 	SKCBF_RX_DATA,		/* received pdu payload */
283 	SKCBF_RX_STATUS,	/* received ddp status */
284 	SKCBF_RX_DATA_DDPD,	/* pdu payload ddp'd */
285 	SKCBF_RX_HCRC_ERR,	/* header digest error */
286 	SKCBF_RX_DCRC_ERR,	/* data digest error */
287 	SKCBF_RX_PAD_ERR,	/* padding byte error */
288 };
289 
290 struct cxgbi_skb_cb {
291 	unsigned char ulp_mode;
292 	unsigned long flags;
293 	unsigned int seq;
294 	union {
295 		struct cxgbi_skb_rx_cb rx;
296 		struct cxgbi_skb_tx_cb tx;
297 	};
298 };
299 
300 #define CXGBI_SKB_CB(skb)	((struct cxgbi_skb_cb *)&((skb)->cb[0]))
301 #define cxgbi_skcb_flags(skb)		(CXGBI_SKB_CB(skb)->flags)
302 #define cxgbi_skcb_ulp_mode(skb)	(CXGBI_SKB_CB(skb)->ulp_mode)
303 #define cxgbi_skcb_tcp_seq(skb)		(CXGBI_SKB_CB(skb)->seq)
304 #define cxgbi_skcb_rx_ddigest(skb)	(CXGBI_SKB_CB(skb)->rx.ddigest)
305 #define cxgbi_skcb_rx_pdulen(skb)	(CXGBI_SKB_CB(skb)->rx.pdulen)
306 #define cxgbi_skcb_tx_wr_next(skb)	(CXGBI_SKB_CB(skb)->tx.wr_next)
307 
308 static inline void cxgbi_skcb_set_flag(struct sk_buff *skb,
309 					enum cxgbi_skcb_flags flag)
310 {
311 	__set_bit(flag, &(cxgbi_skcb_flags(skb)));
312 }
313 
314 static inline void cxgbi_skcb_clear_flag(struct sk_buff *skb,
315 					enum cxgbi_skcb_flags flag)
316 {
317 	__clear_bit(flag, &(cxgbi_skcb_flags(skb)));
318 }
319 
320 static inline int cxgbi_skcb_test_flag(const struct sk_buff *skb,
321 				       enum cxgbi_skcb_flags flag)
322 {
323 	return test_bit(flag, &(cxgbi_skcb_flags(skb)));
324 }
325 
326 static inline void cxgbi_sock_set_flag(struct cxgbi_sock *csk,
327 					enum cxgbi_sock_flags flag)
328 {
329 	__set_bit(flag, &csk->flags);
330 	log_debug(1 << CXGBI_DBG_SOCK,
331 		"csk 0x%p,%u,0x%lx, bit %d.\n",
332 		csk, csk->state, csk->flags, flag);
333 }
334 
335 static inline void cxgbi_sock_clear_flag(struct cxgbi_sock *csk,
336 					enum cxgbi_sock_flags flag)
337 {
338 	__clear_bit(flag, &csk->flags);
339 	log_debug(1 << CXGBI_DBG_SOCK,
340 		"csk 0x%p,%u,0x%lx, bit %d.\n",
341 		csk, csk->state, csk->flags, flag);
342 }
343 
344 static inline int cxgbi_sock_flag(struct cxgbi_sock *csk,
345 				enum cxgbi_sock_flags flag)
346 {
347 	if (csk == NULL)
348 		return 0;
349 	return test_bit(flag, &csk->flags);
350 }
351 
352 static inline void cxgbi_sock_set_state(struct cxgbi_sock *csk, int state)
353 {
354 	log_debug(1 << CXGBI_DBG_SOCK,
355 		"csk 0x%p,%u,0x%lx, state -> %u.\n",
356 		csk, csk->state, csk->flags, state);
357 	csk->state = state;
358 }
359 
360 static inline void cxgbi_sock_free(struct kref *kref)
361 {
362 	struct cxgbi_sock *csk = container_of(kref,
363 						struct cxgbi_sock,
364 						refcnt);
365 	if (csk) {
366 		log_debug(1 << CXGBI_DBG_SOCK,
367 			"free csk 0x%p, state %u, flags 0x%lx\n",
368 			csk, csk->state, csk->flags);
369 		kfree(csk);
370 	}
371 }
372 
373 static inline void __cxgbi_sock_put(const char *fn, struct cxgbi_sock *csk)
374 {
375 	log_debug(1 << CXGBI_DBG_SOCK,
376 		"%s, put csk 0x%p, ref %u-1.\n",
377 		fn, csk, atomic_read(&csk->refcnt.refcount));
378 	kref_put(&csk->refcnt, cxgbi_sock_free);
379 }
380 #define cxgbi_sock_put(csk)	__cxgbi_sock_put(__func__, csk)
381 
382 static inline void __cxgbi_sock_get(const char *fn, struct cxgbi_sock *csk)
383 {
384 	log_debug(1 << CXGBI_DBG_SOCK,
385 		"%s, get csk 0x%p, ref %u+1.\n",
386 		fn, csk, atomic_read(&csk->refcnt.refcount));
387 	kref_get(&csk->refcnt);
388 }
389 #define cxgbi_sock_get(csk)	__cxgbi_sock_get(__func__, csk)
390 
391 static inline int cxgbi_sock_is_closing(struct cxgbi_sock *csk)
392 {
393 	return csk->state >= CTP_ACTIVE_CLOSE;
394 }
395 
396 static inline int cxgbi_sock_is_established(struct cxgbi_sock *csk)
397 {
398 	return csk->state == CTP_ESTABLISHED;
399 }
400 
401 static inline void cxgbi_sock_purge_write_queue(struct cxgbi_sock *csk)
402 {
403 	struct sk_buff *skb;
404 
405 	while ((skb = __skb_dequeue(&csk->write_queue)))
406 		__kfree_skb(skb);
407 }
408 
409 static inline unsigned int cxgbi_sock_compute_wscale(unsigned int win)
410 {
411 	unsigned int wscale = 0;
412 
413 	while (wscale < 14 && (65535 << wscale) < win)
414 		wscale++;
415 	return wscale;
416 }
417 
418 static inline struct sk_buff *alloc_wr(int wrlen, int dlen, gfp_t gfp)
419 {
420 	struct sk_buff *skb = alloc_skb(wrlen + dlen, gfp);
421 
422 	if (skb) {
423 		__skb_put(skb, wrlen);
424 		memset(skb->head, 0, wrlen + dlen);
425 	} else
426 		pr_info("alloc cpl wr skb %u+%u, OOM.\n", wrlen, dlen);
427 	return skb;
428 }
429 
430 
431 /*
432  * The number of WRs needed for an skb depends on the number of fragments
433  * in the skb and whether it has any payload in its main body.  This maps the
434  * length of the gather list represented by an skb into the # of necessary WRs.
435  * The extra two fragments are for iscsi bhs and payload padding.
436  */
437 #define SKB_WR_LIST_SIZE	 (MAX_SKB_FRAGS + 2)
438 
439 static inline void cxgbi_sock_reset_wr_list(struct cxgbi_sock *csk)
440 {
441 	csk->wr_pending_head = csk->wr_pending_tail = NULL;
442 }
443 
444 static inline void cxgbi_sock_enqueue_wr(struct cxgbi_sock *csk,
445 					  struct sk_buff *skb)
446 {
447 	cxgbi_skcb_tx_wr_next(skb) = NULL;
448 	/*
449 	 * We want to take an extra reference since both us and the driver
450 	 * need to free the packet before it's really freed. We know there's
451 	 * just one user currently so we use atomic_set rather than skb_get
452 	 * to avoid the atomic op.
453 	 */
454 	atomic_set(&skb->users, 2);
455 
456 	if (!csk->wr_pending_head)
457 		csk->wr_pending_head = skb;
458 	else
459 		cxgbi_skcb_tx_wr_next(csk->wr_pending_tail) = skb;
460 	csk->wr_pending_tail = skb;
461 }
462 
463 static inline int cxgbi_sock_count_pending_wrs(const struct cxgbi_sock *csk)
464 {
465 	int n = 0;
466 	const struct sk_buff *skb = csk->wr_pending_head;
467 
468 	while (skb) {
469 		n += skb->csum;
470 		skb = cxgbi_skcb_tx_wr_next(skb);
471 	}
472 	return n;
473 }
474 
475 static inline struct sk_buff *cxgbi_sock_peek_wr(const struct cxgbi_sock *csk)
476 {
477 	return csk->wr_pending_head;
478 }
479 
480 static inline struct sk_buff *cxgbi_sock_dequeue_wr(struct cxgbi_sock *csk)
481 {
482 	struct sk_buff *skb = csk->wr_pending_head;
483 
484 	if (likely(skb)) {
485 		csk->wr_pending_head = cxgbi_skcb_tx_wr_next(skb);
486 		cxgbi_skcb_tx_wr_next(skb) = NULL;
487 	}
488 	return skb;
489 }
490 
491 void cxgbi_sock_check_wr_invariants(const struct cxgbi_sock *);
492 void cxgbi_sock_purge_wr_queue(struct cxgbi_sock *);
493 void cxgbi_sock_skb_entail(struct cxgbi_sock *, struct sk_buff *);
494 void cxgbi_sock_fail_act_open(struct cxgbi_sock *, int);
495 void cxgbi_sock_act_open_req_arp_failure(void *, struct sk_buff *);
496 void cxgbi_sock_closed(struct cxgbi_sock *);
497 void cxgbi_sock_established(struct cxgbi_sock *, unsigned int, unsigned int);
498 void cxgbi_sock_rcv_abort_rpl(struct cxgbi_sock *);
499 void cxgbi_sock_rcv_peer_close(struct cxgbi_sock *);
500 void cxgbi_sock_rcv_close_conn_rpl(struct cxgbi_sock *, u32);
501 void cxgbi_sock_rcv_wr_ack(struct cxgbi_sock *, unsigned int, unsigned int,
502 				int);
503 unsigned int cxgbi_sock_select_mss(struct cxgbi_sock *, unsigned int);
504 void cxgbi_sock_free_cpl_skbs(struct cxgbi_sock *);
505 
506 struct cxgbi_hba {
507 	struct net_device *ndev;
508 	struct net_device *vdev;	/* vlan dev */
509 	struct Scsi_Host *shost;
510 	struct cxgbi_device *cdev;
511 	__be32 ipv4addr;
512 	unsigned char port_id;
513 };
514 
515 struct cxgbi_ports_map {
516 	unsigned int max_connect;
517 	unsigned int used;
518 	unsigned short sport_base;
519 	spinlock_t lock;
520 	unsigned int next;
521 	struct cxgbi_sock **port_csk;
522 };
523 
524 #define CXGBI_FLAG_DEV_T3		0x1
525 #define CXGBI_FLAG_DEV_T4		0x2
526 #define CXGBI_FLAG_ADAPTER_RESET	0x4
527 #define CXGBI_FLAG_IPV4_SET		0x10
528 struct cxgbi_device {
529 	struct list_head list_head;
530 	struct list_head rcu_node;
531 	unsigned int flags;
532 	struct net_device **ports;
533 	void *lldev;
534 	struct cxgbi_hba **hbas;
535 	const unsigned short *mtus;
536 	unsigned char nmtus;
537 	unsigned char nports;
538 	struct pci_dev *pdev;
539 	struct dentry *debugfs_root;
540 	struct iscsi_transport *itp;
541 
542 	unsigned int pfvf;
543 	unsigned int snd_win;
544 	unsigned int rcv_win;
545 	unsigned int rx_credit_thres;
546 	unsigned int skb_tx_rsvd;
547 	unsigned int skb_rx_extra;	/* for msg coalesced mode */
548 	unsigned int tx_max_size;
549 	unsigned int rx_max_size;
550 	struct cxgbi_ports_map pmap;
551 	struct cxgbi_tag_format tag_format;
552 	struct cxgbi_ddp_info *ddp;
553 
554 	void (*dev_ddp_cleanup)(struct cxgbi_device *);
555 	int (*csk_ddp_set)(struct cxgbi_sock *, struct cxgbi_pagepod_hdr *,
556 				unsigned int, unsigned int,
557 				struct cxgbi_gather_list *);
558 	void (*csk_ddp_clear)(struct cxgbi_hba *,
559 				unsigned int, unsigned int, unsigned int);
560 	int (*csk_ddp_setup_digest)(struct cxgbi_sock *,
561 				unsigned int, int, int, int);
562 	int (*csk_ddp_setup_pgidx)(struct cxgbi_sock *,
563 				unsigned int, int, bool);
564 
565 	void (*csk_release_offload_resources)(struct cxgbi_sock *);
566 	int (*csk_rx_pdu_ready)(struct cxgbi_sock *, struct sk_buff *);
567 	u32 (*csk_send_rx_credits)(struct cxgbi_sock *, u32);
568 	int (*csk_push_tx_frames)(struct cxgbi_sock *, int);
569 	void (*csk_send_abort_req)(struct cxgbi_sock *);
570 	void (*csk_send_close_req)(struct cxgbi_sock *);
571 	int (*csk_alloc_cpls)(struct cxgbi_sock *);
572 	int (*csk_init_act_open)(struct cxgbi_sock *);
573 
574 	void *dd_data;
575 };
576 #define cxgbi_cdev_priv(cdev)	((cdev)->dd_data)
577 
578 struct cxgbi_conn {
579 	struct cxgbi_endpoint *cep;
580 	struct iscsi_conn *iconn;
581 	struct cxgbi_hba *chba;
582 	u32 task_idx_bits;
583 };
584 
585 struct cxgbi_endpoint {
586 	struct cxgbi_conn *cconn;
587 	struct cxgbi_hba *chba;
588 	struct cxgbi_sock *csk;
589 };
590 
591 #define MAX_PDU_FRAGS	((ULP2_MAX_PDU_PAYLOAD + 512 - 1) / 512)
592 struct cxgbi_task_data {
593 	unsigned short nr_frags;
594 	struct page_frag frags[MAX_PDU_FRAGS];
595 	struct sk_buff *skb;
596 	unsigned int offset;
597 	unsigned int count;
598 	unsigned int sgoffset;
599 };
600 #define iscsi_task_cxgbi_data(task) \
601 	((task)->dd_data + sizeof(struct iscsi_tcp_task))
602 
603 static inline int cxgbi_is_ddp_tag(struct cxgbi_tag_format *tformat, u32 tag)
604 {
605 	return !(tag & (1 << (tformat->rsvd_bits + tformat->rsvd_shift - 1)));
606 }
607 
608 static inline int cxgbi_sw_tag_usable(struct cxgbi_tag_format *tformat,
609 					u32 sw_tag)
610 {
611 	sw_tag >>= (32 - tformat->rsvd_bits);
612 	return !sw_tag;
613 }
614 
615 static inline u32 cxgbi_set_non_ddp_tag(struct cxgbi_tag_format *tformat,
616 					u32 sw_tag)
617 {
618 	unsigned char shift = tformat->rsvd_bits + tformat->rsvd_shift - 1;
619 	u32 mask = (1 << shift) - 1;
620 
621 	if (sw_tag && (sw_tag & ~mask)) {
622 		u32 v1 = sw_tag & ((1 << shift) - 1);
623 		u32 v2 = (sw_tag >> (shift - 1)) << shift;
624 
625 		return v2 | v1 | 1 << shift;
626 	}
627 
628 	return sw_tag | 1 << shift;
629 }
630 
631 static inline u32 cxgbi_ddp_tag_base(struct cxgbi_tag_format *tformat,
632 					u32 sw_tag)
633 {
634 	u32 mask = (1 << tformat->rsvd_shift) - 1;
635 
636 	if (sw_tag && (sw_tag & ~mask)) {
637 		u32 v1 = sw_tag & mask;
638 		u32 v2 = sw_tag >> tformat->rsvd_shift;
639 
640 		v2 <<= tformat->rsvd_bits + tformat->rsvd_shift;
641 
642 		return v2 | v1;
643 	}
644 
645 	return sw_tag;
646 }
647 
648 static inline u32 cxgbi_tag_rsvd_bits(struct cxgbi_tag_format *tformat,
649 					u32 tag)
650 {
651 	if (cxgbi_is_ddp_tag(tformat, tag))
652 		return (tag >> tformat->rsvd_shift) & tformat->rsvd_mask;
653 
654 	return 0;
655 }
656 
657 static inline u32 cxgbi_tag_nonrsvd_bits(struct cxgbi_tag_format *tformat,
658 					u32 tag)
659 {
660 	unsigned char shift = tformat->rsvd_bits + tformat->rsvd_shift - 1;
661 	u32 v1, v2;
662 
663 	if (cxgbi_is_ddp_tag(tformat, tag)) {
664 		v1 = tag & ((1 << tformat->rsvd_shift) - 1);
665 		v2 = (tag >> (shift + 1)) << tformat->rsvd_shift;
666 	} else {
667 		u32 mask = (1 << shift) - 1;
668 		tag &= ~(1 << shift);
669 		v1 = tag & mask;
670 		v2 = (tag >> 1) & ~mask;
671 	}
672 	return v1 | v2;
673 }
674 
675 static inline void *cxgbi_alloc_big_mem(unsigned int size,
676 					gfp_t gfp)
677 {
678 	void *p = kzalloc(size, gfp | __GFP_NOWARN);
679 
680 	if (!p)
681 		p = vzalloc(size);
682 
683 	return p;
684 }
685 
686 static inline void cxgbi_free_big_mem(void *addr)
687 {
688 	if (is_vmalloc_addr(addr))
689 		vfree(addr);
690 	else
691 		kfree(addr);
692 }
693 
694 static inline void cxgbi_set_iscsi_ipv4(struct cxgbi_hba *chba, __be32 ipaddr)
695 {
696 	if (chba->cdev->flags & CXGBI_FLAG_IPV4_SET)
697 		chba->ipv4addr = ipaddr;
698 	else
699 		pr_info("set iscsi ipv4 NOT supported, using %s ipv4.\n",
700 			chba->ndev->name);
701 }
702 
703 struct cxgbi_device *cxgbi_device_register(unsigned int, unsigned int);
704 void cxgbi_device_unregister(struct cxgbi_device *);
705 void cxgbi_device_unregister_all(unsigned int flag);
706 struct cxgbi_device *cxgbi_device_find_by_lldev(void *);
707 struct cxgbi_device *cxgbi_device_find_by_netdev(struct net_device *, int *);
708 struct cxgbi_device *cxgbi_device_find_by_netdev_rcu(struct net_device *,
709 						     int *);
710 int cxgbi_hbas_add(struct cxgbi_device *, u64, unsigned int,
711 			struct scsi_host_template *,
712 			struct scsi_transport_template *);
713 void cxgbi_hbas_remove(struct cxgbi_device *);
714 
715 int cxgbi_device_portmap_create(struct cxgbi_device *cdev, unsigned int base,
716 			unsigned int max_conn);
717 void cxgbi_device_portmap_cleanup(struct cxgbi_device *cdev);
718 
719 void cxgbi_conn_tx_open(struct cxgbi_sock *);
720 void cxgbi_conn_pdu_ready(struct cxgbi_sock *);
721 int cxgbi_conn_alloc_pdu(struct iscsi_task *, u8);
722 int cxgbi_conn_init_pdu(struct iscsi_task *, unsigned int , unsigned int);
723 int cxgbi_conn_xmit_pdu(struct iscsi_task *);
724 
725 void cxgbi_cleanup_task(struct iscsi_task *task);
726 
727 umode_t cxgbi_attr_is_visible(int param_type, int param);
728 void cxgbi_get_conn_stats(struct iscsi_cls_conn *, struct iscsi_stats *);
729 int cxgbi_set_conn_param(struct iscsi_cls_conn *,
730 			enum iscsi_param, char *, int);
731 int cxgbi_get_ep_param(struct iscsi_endpoint *ep, enum iscsi_param, char *);
732 struct iscsi_cls_conn *cxgbi_create_conn(struct iscsi_cls_session *, u32);
733 int cxgbi_bind_conn(struct iscsi_cls_session *,
734 			struct iscsi_cls_conn *, u64, int);
735 void cxgbi_destroy_session(struct iscsi_cls_session *);
736 struct iscsi_cls_session *cxgbi_create_session(struct iscsi_endpoint *,
737 			u16, u16, u32);
738 int cxgbi_set_host_param(struct Scsi_Host *,
739 			enum iscsi_host_param, char *, int);
740 int cxgbi_get_host_param(struct Scsi_Host *, enum iscsi_host_param, char *);
741 struct iscsi_endpoint *cxgbi_ep_connect(struct Scsi_Host *,
742 			struct sockaddr *, int);
743 int cxgbi_ep_poll(struct iscsi_endpoint *, int);
744 void cxgbi_ep_disconnect(struct iscsi_endpoint *);
745 
746 int cxgbi_iscsi_init(struct iscsi_transport *,
747 			struct scsi_transport_template **);
748 void cxgbi_iscsi_cleanup(struct iscsi_transport *,
749 			struct scsi_transport_template **);
750 void cxgbi_parse_pdu_itt(struct iscsi_conn *, itt_t, int *, int *);
751 int cxgbi_ddp_init(struct cxgbi_device *, unsigned int, unsigned int,
752 			unsigned int, unsigned int);
753 int cxgbi_ddp_cleanup(struct cxgbi_device *);
754 void cxgbi_ddp_page_size_factor(int *);
755 void cxgbi_ddp_ppod_clear(struct cxgbi_pagepod *);
756 void cxgbi_ddp_ppod_set(struct cxgbi_pagepod *, struct cxgbi_pagepod_hdr *,
757 			struct cxgbi_gather_list *, unsigned int);
758 #endif	/*__LIBCXGBI_H__*/
759