[linux-2.6-block.git] / include / scsi / libiscsi_tcp.h

/* SPDX-License-Identifier: GPL-2.0-or-later */
/*
 * iSCSI over TCP/IP Data-Path lib
 *
 * Copyright (C) 2008 Mike Christie
 * Copyright (C) 2008 Red Hat, Inc.  All rights reserved.
 * maintained by open-iscsi@googlegroups.com
 *
 * See the file COPYING included with this distribution for more details.
 */

#ifndef LIBISCSI_TCP_H
#define LIBISCSI_TCP_H

#include <scsi/libiscsi.h>

struct iscsi_tcp_conn;
struct iscsi_segment;
struct sk_buff;
struct ahash_request;

typedef int iscsi_segment_done_fn_t(struct iscsi_tcp_conn *,
				    struct iscsi_segment *);

struct iscsi_segment {
	unsigned char		*data;
	unsigned int		size;
	unsigned int		copied;
	unsigned int		total_size;
	unsigned int		total_copied;

	struct ahash_request	*hash;
	unsigned char		padbuf[ISCSI_PAD_LEN];
	unsigned char		recv_digest[ISCSI_DIGEST_SIZE];
	unsigned char		digest[ISCSI_DIGEST_SIZE];
	unsigned int		digest_len;

	struct scatterlist	*sg;
	void			*sg_mapped;
	unsigned int		sg_offset;
	bool			atomic_mapped;

	iscsi_segment_done_fn_t	*done;
};

/* Socket connection receive helper */
struct iscsi_tcp_recv {
	struct iscsi_hdr	*hdr;
	struct iscsi_segment	segment;

	/* Allocate buffer for BHS + AHS */
	uint32_t		hdr_buf[64];

	/* copied and flipped values */
	int			datalen;
};

struct iscsi_tcp_conn {
	struct iscsi_conn	*iscsi_conn;
	void			*dd_data;
	int			stop_stage;	/* conn_stop() flag: *
						 * stop to recover,  *
						 * stop to terminate */
	/* control data */
	struct iscsi_tcp_recv	in;		/* TCP receive context */
	/* CRC32C (Rx) LLD should set this is they do not offload */
	struct ahash_request	*rx_hash;
};

struct iscsi_tcp_task {
	uint32_t		exp_datasn;	/* expected target's R2TSN/DataSN */
	int			data_offset;
	struct iscsi_r2t_info	*r2t;		/* in progress solict R2T */
	struct iscsi_pool	r2tpool;
	struct kfifo		r2tqueue;
	void			*dd_data;
	spinlock_t		pool2queue;
	spinlock_t		queue2pool;
};

enum {
	ISCSI_TCP_SEGMENT_DONE,		/* curr seg has been processed */
	ISCSI_TCP_SKB_DONE,		/* skb is out of data */
	ISCSI_TCP_CONN_ERR,		/* iscsi layer has fired a conn err */
	ISCSI_TCP_SUSPENDED,		/* conn is suspended */
};

extern void iscsi_tcp_hdr_recv_prep(struct iscsi_tcp_conn *tcp_conn);
extern int iscsi_tcp_recv_skb(struct iscsi_conn *conn, struct sk_buff *skb,
			      unsigned int offset, bool offloaded, int *status);
extern void iscsi_tcp_cleanup_task(struct iscsi_task *task);
extern int iscsi_tcp_task_init(struct iscsi_task *task);
extern int iscsi_tcp_task_xmit(struct iscsi_task *task);

/* segment helpers */
extern int iscsi_tcp_recv_segment_is_hdr(struct iscsi_tcp_conn *tcp_conn);
extern int iscsi_tcp_segment_done(struct iscsi_tcp_conn *tcp_conn,
				  struct iscsi_segment *segment, int recv,
				  unsigned copied);
extern void iscsi_tcp_segment_unmap(struct iscsi_segment *segment);

extern void iscsi_segment_init_linear(struct iscsi_segment *segment,
				      void *data, size_t size,
				      iscsi_segment_done_fn_t *done,
				      struct ahash_request *hash);
extern int
iscsi_segment_seek_sg(struct iscsi_segment *segment,
		      struct scatterlist *sg_list, unsigned int sg_count,
		      unsigned int offset, size_t size,
		      iscsi_segment_done_fn_t *done,
		      struct ahash_request *hash);

/* digest helpers */
extern void iscsi_tcp_dgst_header(struct ahash_request *hash, const void *hdr,
				  size_t hdrlen,
				  unsigned char digest[ISCSI_DIGEST_SIZE]);
extern struct iscsi_cls_conn *
iscsi_tcp_conn_setup(struct iscsi_cls_session *cls_session, int dd_data_size,
		     uint32_t conn_idx);
extern void iscsi_tcp_conn_teardown(struct iscsi_cls_conn *cls_conn);

/* misc helpers */
extern int iscsi_tcp_r2tpool_alloc(struct iscsi_session *session);
extern void iscsi_tcp_r2tpool_free(struct iscsi_session *session);
extern int iscsi_tcp_set_max_r2t(struct iscsi_conn *conn, char *buf);
extern void iscsi_tcp_conn_get_stats(struct iscsi_cls_conn *cls_conn,
				     struct iscsi_stats *stats);
#endif /* LIBISCSI_TCP_H */
Commit	Line	Data
c942fddf	1	/* SPDX-License-Identifier: GPL-2.0-or-later */
a081c13e MC	2	/*
	3	* iSCSI over TCP/IP Data-Path lib
	4	*
	5	* Copyright (C) 2008 Mike Christie
	6	* Copyright (C) 2008 Red Hat, Inc. All rights reserved.
	7	* maintained by open-iscsi@googlegroups.com
	8	*
a081c13e MC	9	* See the file COPYING included with this distribution for more details.
	10	*/
	11
	12	#ifndef LIBISCSI_TCP_H
	13	#define LIBISCSI_TCP_H
	14
	15	#include <scsi/libiscsi.h>
	16
	17	struct iscsi_tcp_conn;
	18	struct iscsi_segment;
	19	struct sk_buff;
5d6ac29b	20	struct ahash_request;
a081c13e MC	21
	22	typedef int iscsi_segment_done_fn_t(struct iscsi_tcp_conn *,
	23	struct iscsi_segment *);
	24
	25	struct iscsi_segment {
	26	unsigned char *data;
	27	unsigned int size;
	28	unsigned int copied;
	29	unsigned int total_size;
	30	unsigned int total_copied;
	31
5d6ac29b	32	struct ahash_request *hash;
2856830b	33	unsigned char padbuf[ISCSI_PAD_LEN];
a081c13e MC	34	unsigned char recv_digest[ISCSI_DIGEST_SIZE];
	35	unsigned char digest[ISCSI_DIGEST_SIZE];
	36	unsigned int digest_len;
	37
	38	struct scatterlist *sg;
	39	void *sg_mapped;
	40	unsigned int sg_offset;
70c7c88a	41	bool atomic_mapped;
a081c13e MC	42
	43	iscsi_segment_done_fn_t *done;
	44	};
	45
25985edc	46	/* Socket connection receive helper */
a081c13e MC	47	struct iscsi_tcp_recv {
	48	struct iscsi_hdr *hdr;
	49	struct iscsi_segment segment;
	50
	51	/* Allocate buffer for BHS + AHS */
	52	uint32_t hdr_buf[64];
	53
	54	/* copied and flipped values */
	55	int datalen;
	56	};
	57
	58	struct iscsi_tcp_conn {
	59	struct iscsi_conn *iscsi_conn;
	60	void *dd_data;
	61	int stop_stage; /* conn_stop() flag: *
	62	* stop to recover, *
	63	* stop to terminate */
	64	/* control data */
	65	struct iscsi_tcp_recv in; /* TCP receive context */
	66	/* CRC32C (Rx) LLD should set this is they do not offload */
5d6ac29b	67	struct ahash_request *rx_hash;
a081c13e MC	68	};
	69
	70	struct iscsi_tcp_task {
	71	uint32_t exp_datasn; /* expected target's R2TSN/DataSN */
	72	int data_offset;
	73	struct iscsi_r2t_info r2t; / in progress solict R2T */
	74	struct iscsi_pool r2tpool;
45465487	75	struct kfifo r2tqueue;
a081c13e	76	void *dd_data;
659743b0 SP	77	spinlock_t pool2queue;
659743b0 SP	78	spinlock_t queue2pool;
a081c13e MC	79	};
	80
	81	enum {
	82	ISCSI_TCP_SEGMENT_DONE, /* curr seg has been processed */
	83	ISCSI_TCP_SKB_DONE, /* skb is out of data */
	84	ISCSI_TCP_CONN_ERR, /* iscsi layer has fired a conn err */
	85	ISCSI_TCP_SUSPENDED, /* conn is suspended */
	86	};
	87
	88	extern void iscsi_tcp_hdr_recv_prep(struct iscsi_tcp_conn *tcp_conn);
	89	extern int iscsi_tcp_recv_skb(struct iscsi_conn conn, struct sk_buff skb,
	90	unsigned int offset, bool offloaded, int *status);
	91	extern void iscsi_tcp_cleanup_task(struct iscsi_task *task);
	92	extern int iscsi_tcp_task_init(struct iscsi_task *task);
	93	extern int iscsi_tcp_task_xmit(struct iscsi_task *task);
	94
	95	/* segment helpers */
	96	extern int iscsi_tcp_recv_segment_is_hdr(struct iscsi_tcp_conn *tcp_conn);
6df19a79 MC	97	extern int iscsi_tcp_segment_done(struct iscsi_tcp_conn *tcp_conn,
6df19a79 MC	98	struct iscsi_segment *segment, int recv,
a081c13e MC	99	unsigned copied);
	100	extern void iscsi_tcp_segment_unmap(struct iscsi_segment *segment);
	101
	102	extern void iscsi_segment_init_linear(struct iscsi_segment *segment,
	103	void *data, size_t size,
	104	iscsi_segment_done_fn_t *done,
5d6ac29b	105	struct ahash_request *hash);
a081c13e MC	106	extern int
	107	iscsi_segment_seek_sg(struct iscsi_segment *segment,
	108	struct scatterlist *sg_list, unsigned int sg_count,
	109	unsigned int offset, size_t size,
5d6ac29b HX	110	iscsi_segment_done_fn_t *done,
5d6ac29b HX	111	struct ahash_request *hash);
a081c13e MC	112
a081c13e MC	113	/* digest helpers */
5d6ac29b	114	extern void iscsi_tcp_dgst_header(struct ahash_request hash, const void hdr,
a081c13e MC	115	size_t hdrlen,
	116	unsigned char digest[ISCSI_DIGEST_SIZE]);
	117	extern struct iscsi_cls_conn *
	118	iscsi_tcp_conn_setup(struct iscsi_cls_session *cls_session, int dd_data_size,
	119	uint32_t conn_idx);
	120	extern void iscsi_tcp_conn_teardown(struct iscsi_cls_conn *cls_conn);
	121
	122	/* misc helpers */
	123	extern int iscsi_tcp_r2tpool_alloc(struct iscsi_session *session);
	124	extern void iscsi_tcp_r2tpool_free(struct iscsi_session *session);
1304be5f	125	extern int iscsi_tcp_set_max_r2t(struct iscsi_conn conn, char buf);
a081c13e MC	126	extern void iscsi_tcp_conn_get_stats(struct iscsi_cls_conn *cls_conn,
	127	struct iscsi_stats *stats);
	128	#endif /* LIBISCSI_TCP_H */