linux/include/scsi/fc_frame.h

/* SPDX-License-Identifier: GPL-2.0-only */
/*
 * Copyright(c) 2007 Intel Corporation. All rights reserved.
 *
 * Maintained at www.Open-FCoE.org
 */

#ifndef _FC_FRAME_H_
#define _FC_FRAME_H_

#include <linux/scatterlist.h>
#include <linux/skbuff.h>
#include <scsi/scsi_cmnd.h>

#include <scsi/fc/fc_fs.h>
#include <scsi/fc/fc_fcp.h>
#include <scsi/fc/fc_encaps.h>

#include <linux/if_ether.h>

/* some helpful macros */

#define ntohll(x) …
#define htonll(x) …

static inline u32 ntoh24(const u8 *p)
{ … }

static inline void hton24(u8 *p, u32 v)
{ … }

/*
 * The fc_frame interface is used to pass frame data between functions.
 * The frame includes the data buffer, length, and SOF / EOF delimiter types.
 * A pointer to the port structure of the receiving port is also includeded.
 */

#define FC_FRAME_HEADROOM …
#define FC_FRAME_TAILROOM …

/* Max number of skb frags allowed, reserving one for fcoe_crc_eof page */
#define FC_FRAME_SG_LEN …

#define fp_skb(fp) …
#define fr_hdr(fp) …
#define fr_len(fp) …
#define fr_cb(fp) …
#define fr_dev(fp) …
#define fr_seq(fp) …
#define fr_sof(fp) …
#define fr_eof(fp) …
#define fr_flags(fp) …
#define fr_encaps(fp) …
#define fr_max_payload(fp) …
#define fr_fsp(fp) …
#define fr_crc(fp) …

struct fc_frame { … };

struct fcoe_rcv_info { … };


/*
 * Get fc_frame pointer for an skb that's already been imported.
 */
static inline struct fcoe_rcv_info *fcoe_dev_from_skb(const struct sk_buff *skb)
{ … }

/*
 * fr_flags.
 */
#define FCPHF_CRC_UNCHECKED …

/*
 * Initialize a frame.
 * We don't do a complete memset here for performance reasons.
 * The caller must set fr_free, fr_hdr, fr_len, fr_sof, and fr_eof eventually.
 */
static inline void fc_frame_init(struct fc_frame *fp)
{ … }

struct fc_frame *fc_frame_alloc_fill(struct fc_lport *, size_t payload_len);
struct fc_frame *_fc_frame_alloc(size_t payload_len);

/*
 * Allocate fc_frame structure and buffer.  Set the initial length to
 * payload_size + sizeof (struct fc_frame_header).
 */
static inline struct fc_frame *fc_frame_alloc(struct fc_lport *dev, size_t len)
{ … }

/*
 * Free the fc_frame structure and buffer.
 */
static inline void fc_frame_free(struct fc_frame *fp)
{ … }

static inline int fc_frame_is_linear(struct fc_frame *fp)
{ … }

/*
 * Get frame header from message in fc_frame structure.
 * This version doesn't do a length check.
 */
static inline
struct fc_frame_header *__fc_frame_header_get(const struct fc_frame *fp)
{ … }

/*
 * Get frame header from message in fc_frame structure.
 * This hides a cast and provides a place to add some checking.
 */
static inline
struct fc_frame_header *fc_frame_header_get(const struct fc_frame *fp)
{ … }

/*
 * Get source FC_ID (S_ID) from frame header in message.
 */
static inline u32 fc_frame_sid(const struct fc_frame *fp)
{ … }

/*
 * Get destination FC_ID (D_ID) from frame header in message.
 */
static inline u32 fc_frame_did(const struct fc_frame *fp)
{ … }

/*
 * Get frame payload from message in fc_frame structure.
 * This hides a cast and provides a place to add some checking.
 * The len parameter is the minimum length for the payload portion.
 * Returns NULL if the frame is too short.
 *
 * This assumes the interesting part of the payload is in the first part
 * of the buffer for received data.  This may not be appropriate to use for
 * buffers being transmitted.
 */
static inline void *fc_frame_payload_get(const struct fc_frame *fp,
					 size_t len)
{ … }

/*
 * Get frame payload opcode (first byte) from message in fc_frame structure.
 * This hides a cast and provides a place to add some checking. Return 0
 * if the frame has no payload.
 */
static inline u8 fc_frame_payload_op(const struct fc_frame *fp)
{ … }

/*
 * Get FC class from frame.
 */
static inline enum fc_class fc_frame_class(const struct fc_frame *fp)
{ … }

/*
 * Check the CRC in a frame.
 * The CRC immediately follows the last data item *AFTER* the length.
 * The return value is zero if the CRC matches.
 */
u32 fc_frame_crc_check(struct fc_frame *);

static inline u8 fc_frame_rctl(const struct fc_frame *fp)
{ … }

static inline bool fc_frame_is_cmd(const struct fc_frame *fp)
{ … }

/*
 * Check for leaks.
 * Print the frame header of any currently allocated frame, assuming there
 * should be none at this point.
 */
void fc_frame_leak_check(void);

static inline void __fc_fill_fc_hdr(struct fc_frame_header *fh,
				    enum fc_rctl r_ctl,
				    u32 did, u32 sid, enum fc_fh_type type,
				    u32 f_ctl, u32 parm_offset)
{ … }

/**
 * fill FC header fields in specified fc_frame
 */
static inline void fc_fill_fc_hdr(struct fc_frame *fp, enum fc_rctl r_ctl,
				  u32 did, u32 sid, enum fc_fh_type type,
				  u32 f_ctl, u32 parm_offset)
{ … }


#endif /* _FC_FRAME_H_ */