xref: /OK3568_Linux_fs/kernel/include/scsi/libiscsi_tcp.h (revision 4882a59341e53eb6f0b4789bf948001014eff981)
1*4882a593Smuzhiyun /* SPDX-License-Identifier: GPL-2.0-or-later */
2*4882a593Smuzhiyun /*
3*4882a593Smuzhiyun  * iSCSI over TCP/IP Data-Path lib
4*4882a593Smuzhiyun  *
5*4882a593Smuzhiyun  * Copyright (C) 2008 Mike Christie
6*4882a593Smuzhiyun  * Copyright (C) 2008 Red Hat, Inc.  All rights reserved.
7*4882a593Smuzhiyun  * maintained by open-iscsi@googlegroups.com
8*4882a593Smuzhiyun  */
9*4882a593Smuzhiyun 
10*4882a593Smuzhiyun #ifndef LIBISCSI_TCP_H
11*4882a593Smuzhiyun #define LIBISCSI_TCP_H
12*4882a593Smuzhiyun 
13*4882a593Smuzhiyun #include <scsi/libiscsi.h>
14*4882a593Smuzhiyun 
15*4882a593Smuzhiyun struct iscsi_tcp_conn;
16*4882a593Smuzhiyun struct iscsi_segment;
17*4882a593Smuzhiyun struct sk_buff;
18*4882a593Smuzhiyun struct ahash_request;
19*4882a593Smuzhiyun 
20*4882a593Smuzhiyun typedef int iscsi_segment_done_fn_t(struct iscsi_tcp_conn *,
21*4882a593Smuzhiyun 				    struct iscsi_segment *);
22*4882a593Smuzhiyun 
23*4882a593Smuzhiyun struct iscsi_segment {
24*4882a593Smuzhiyun 	unsigned char		*data;
25*4882a593Smuzhiyun 	unsigned int		size;
26*4882a593Smuzhiyun 	unsigned int		copied;
27*4882a593Smuzhiyun 	unsigned int		total_size;
28*4882a593Smuzhiyun 	unsigned int		total_copied;
29*4882a593Smuzhiyun 
30*4882a593Smuzhiyun 	struct ahash_request	*hash;
31*4882a593Smuzhiyun 	unsigned char		padbuf[ISCSI_PAD_LEN];
32*4882a593Smuzhiyun 	unsigned char		recv_digest[ISCSI_DIGEST_SIZE];
33*4882a593Smuzhiyun 	unsigned char		digest[ISCSI_DIGEST_SIZE];
34*4882a593Smuzhiyun 	unsigned int		digest_len;
35*4882a593Smuzhiyun 
36*4882a593Smuzhiyun 	struct scatterlist	*sg;
37*4882a593Smuzhiyun 	void			*sg_mapped;
38*4882a593Smuzhiyun 	unsigned int		sg_offset;
39*4882a593Smuzhiyun 	bool			atomic_mapped;
40*4882a593Smuzhiyun 
41*4882a593Smuzhiyun 	iscsi_segment_done_fn_t	*done;
42*4882a593Smuzhiyun };
43*4882a593Smuzhiyun 
44*4882a593Smuzhiyun /* Socket connection receive helper */
45*4882a593Smuzhiyun struct iscsi_tcp_recv {
46*4882a593Smuzhiyun 	struct iscsi_hdr	*hdr;
47*4882a593Smuzhiyun 	struct iscsi_segment	segment;
48*4882a593Smuzhiyun 
49*4882a593Smuzhiyun 	/* Allocate buffer for BHS + AHS */
50*4882a593Smuzhiyun 	uint32_t		hdr_buf[64];
51*4882a593Smuzhiyun 
52*4882a593Smuzhiyun 	/* copied and flipped values */
53*4882a593Smuzhiyun 	int			datalen;
54*4882a593Smuzhiyun };
55*4882a593Smuzhiyun 
56*4882a593Smuzhiyun struct iscsi_tcp_conn {
57*4882a593Smuzhiyun 	struct iscsi_conn	*iscsi_conn;
58*4882a593Smuzhiyun 	void			*dd_data;
59*4882a593Smuzhiyun 	int			stop_stage;	/* conn_stop() flag: *
60*4882a593Smuzhiyun 						 * stop to recover,  *
61*4882a593Smuzhiyun 						 * stop to terminate */
62*4882a593Smuzhiyun 	/* control data */
63*4882a593Smuzhiyun 	struct iscsi_tcp_recv	in;		/* TCP receive context */
64*4882a593Smuzhiyun 	/* CRC32C (Rx) LLD should set this is they do not offload */
65*4882a593Smuzhiyun 	struct ahash_request	*rx_hash;
66*4882a593Smuzhiyun };
67*4882a593Smuzhiyun 
68*4882a593Smuzhiyun struct iscsi_tcp_task {
69*4882a593Smuzhiyun 	uint32_t		exp_datasn;	/* expected target's R2TSN/DataSN */
70*4882a593Smuzhiyun 	int			data_offset;
71*4882a593Smuzhiyun 	struct iscsi_r2t_info	*r2t;		/* in progress solict R2T */
72*4882a593Smuzhiyun 	struct iscsi_pool	r2tpool;
73*4882a593Smuzhiyun 	struct kfifo		r2tqueue;
74*4882a593Smuzhiyun 	void			*dd_data;
75*4882a593Smuzhiyun 	spinlock_t		pool2queue;
76*4882a593Smuzhiyun 	spinlock_t		queue2pool;
77*4882a593Smuzhiyun };
78*4882a593Smuzhiyun 
79*4882a593Smuzhiyun enum {
80*4882a593Smuzhiyun 	ISCSI_TCP_SEGMENT_DONE,		/* curr seg has been processed */
81*4882a593Smuzhiyun 	ISCSI_TCP_SKB_DONE,		/* skb is out of data */
82*4882a593Smuzhiyun 	ISCSI_TCP_CONN_ERR,		/* iscsi layer has fired a conn err */
83*4882a593Smuzhiyun 	ISCSI_TCP_SUSPENDED,		/* conn is suspended */
84*4882a593Smuzhiyun };
85*4882a593Smuzhiyun 
86*4882a593Smuzhiyun extern void iscsi_tcp_hdr_recv_prep(struct iscsi_tcp_conn *tcp_conn);
87*4882a593Smuzhiyun extern int iscsi_tcp_recv_skb(struct iscsi_conn *conn, struct sk_buff *skb,
88*4882a593Smuzhiyun 			      unsigned int offset, bool offloaded, int *status);
89*4882a593Smuzhiyun extern void iscsi_tcp_cleanup_task(struct iscsi_task *task);
90*4882a593Smuzhiyun extern int iscsi_tcp_task_init(struct iscsi_task *task);
91*4882a593Smuzhiyun extern int iscsi_tcp_task_xmit(struct iscsi_task *task);
92*4882a593Smuzhiyun 
93*4882a593Smuzhiyun /* segment helpers */
94*4882a593Smuzhiyun extern int iscsi_tcp_recv_segment_is_hdr(struct iscsi_tcp_conn *tcp_conn);
95*4882a593Smuzhiyun extern int iscsi_tcp_segment_done(struct iscsi_tcp_conn *tcp_conn,
96*4882a593Smuzhiyun 				  struct iscsi_segment *segment, int recv,
97*4882a593Smuzhiyun 				  unsigned copied);
98*4882a593Smuzhiyun extern void iscsi_tcp_segment_unmap(struct iscsi_segment *segment);
99*4882a593Smuzhiyun 
100*4882a593Smuzhiyun extern void iscsi_segment_init_linear(struct iscsi_segment *segment,
101*4882a593Smuzhiyun 				      void *data, size_t size,
102*4882a593Smuzhiyun 				      iscsi_segment_done_fn_t *done,
103*4882a593Smuzhiyun 				      struct ahash_request *hash);
104*4882a593Smuzhiyun extern int
105*4882a593Smuzhiyun iscsi_segment_seek_sg(struct iscsi_segment *segment,
106*4882a593Smuzhiyun 		      struct scatterlist *sg_list, unsigned int sg_count,
107*4882a593Smuzhiyun 		      unsigned int offset, size_t size,
108*4882a593Smuzhiyun 		      iscsi_segment_done_fn_t *done,
109*4882a593Smuzhiyun 		      struct ahash_request *hash);
110*4882a593Smuzhiyun 
111*4882a593Smuzhiyun /* digest helpers */
112*4882a593Smuzhiyun extern void iscsi_tcp_dgst_header(struct ahash_request *hash, const void *hdr,
113*4882a593Smuzhiyun 				  size_t hdrlen,
114*4882a593Smuzhiyun 				  unsigned char digest[ISCSI_DIGEST_SIZE]);
115*4882a593Smuzhiyun extern struct iscsi_cls_conn *
116*4882a593Smuzhiyun iscsi_tcp_conn_setup(struct iscsi_cls_session *cls_session, int dd_data_size,
117*4882a593Smuzhiyun 		     uint32_t conn_idx);
118*4882a593Smuzhiyun extern void iscsi_tcp_conn_teardown(struct iscsi_cls_conn *cls_conn);
119*4882a593Smuzhiyun 
120*4882a593Smuzhiyun /* misc helpers */
121*4882a593Smuzhiyun extern int iscsi_tcp_r2tpool_alloc(struct iscsi_session *session);
122*4882a593Smuzhiyun extern void iscsi_tcp_r2tpool_free(struct iscsi_session *session);
123*4882a593Smuzhiyun extern int iscsi_tcp_set_max_r2t(struct iscsi_conn *conn, char *buf);
124*4882a593Smuzhiyun extern void iscsi_tcp_conn_get_stats(struct iscsi_cls_conn *cls_conn,
125*4882a593Smuzhiyun 				     struct iscsi_stats *stats);
126*4882a593Smuzhiyun #endif /* LIBISCSI_TCP_H */
127