/* 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) be64_to_cpu(x)#define htonll(x) cpu_to_be64(x) static inline u32 ntoh24(const u8 *p){	return (p[0] << 16) | (p[1] << 8) | p[2];} static inline void hton24(u8 *p, u32 v){	p[0] = (v >> 16) & 0xff;	p[1] = (v >> 8) & 0xff;	p[2] = v & 0xff;} /* * 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	32	/* headroom for VLAN + FCoE headers */#define	FC_FRAME_TAILROOM	8	/* trailer space for FCoE */ /* Max number of skb frags allowed, reserving one for fcoe_crc_eof page */#define FC_FRAME_SG_LEN		(MAX_SKB_FRAGS - 1) #define fp_skb(fp)	(&((fp)->skb))#define fr_hdr(fp)	((fp)->skb.data)#define fr_len(fp)	((fp)->skb.len)#define fr_cb(fp)	((struct fcoe_rcv_info *)&((fp)->skb.cb[0]))#define fr_dev(fp)	(fr_cb(fp)->fr_dev)#define fr_seq(fp)	(fr_cb(fp)->fr_seq)#define fr_sof(fp)	(fr_cb(fp)->fr_sof)#define fr_eof(fp)	(fr_cb(fp)->fr_eof)#define fr_flags(fp)	(fr_cb(fp)->fr_flags)#define fr_encaps(fp)	(fr_cb(fp)->fr_encaps)#define fr_max_payload(fp)	(fr_cb(fp)->fr_max_payload)#define fr_fsp(fp)	(fr_cb(fp)->fr_fsp)#define fr_crc(fp)	(fr_cb(fp)->fr_crc) struct fc_frame {	struct sk_buff skb;}; struct fcoe_rcv_info {	struct fc_lport	*fr_dev;	/* transport layer private pointer */	struct fc_seq	*fr_seq;	/* for use with exchange manager */	struct fc_fcp_pkt *fr_fsp;	/* for the corresponding fcp I/O */	u32		fr_crc;	u16		fr_max_payload;	/* max FC payload */	u8		fr_sof;		/* start of frame delimiter */	u8		fr_eof;		/* end of frame delimiter */	u8		fr_flags;	/* flags - see below */	u8		fr_encaps;	/* LLD encapsulation info (e.g. FIP) */	u8		granted_mac[ETH_ALEN]; /* FCoE MAC address */};  /* * 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){	BUILD_BUG_ON(sizeof(struct fcoe_rcv_info) > sizeof(skb->cb));	return (struct fcoe_rcv_info *) skb->cb;} /* * fr_flags. */#define	FCPHF_CRC_UNCHECKED	0x01	/* CRC not computed, still appended */ /* * 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){	fr_dev(fp) = NULL;	fr_seq(fp) = NULL;	fr_flags(fp) = 0;	fr_encaps(fp) = 0;} 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){	struct fc_frame *fp; 	/*	 * Note: Since len will often be a constant multiple of 4,	 * this check will usually be evaluated and eliminated at compile time.	 */	if (len && len % 4)		fp = fc_frame_alloc_fill(dev, len);	else		fp = _fc_frame_alloc(len);	return fp;} /* * Free the fc_frame structure and buffer. */static inline void fc_frame_free(struct fc_frame *fp){	kfree_skb(fp_skb(fp));} static inline int fc_frame_is_linear(struct fc_frame *fp){	return !skb_is_nonlinear(fp_skb(fp));} /* * Get frame header from message in fc_frame structure. * This version doesn't do a length check. */static inlinestruct fc_frame_header *__fc_frame_header_get(const struct fc_frame *fp){	return (struct fc_frame_header *)fr_hdr(fp);} /* * Get frame header from message in fc_frame structure. * This hides a cast and provides a place to add some checking. */static inlinestruct fc_frame_header *fc_frame_header_get(const struct fc_frame *fp){	WARN_ON(fr_len(fp) < sizeof(struct fc_frame_header));	return __fc_frame_header_get(fp);} /* * Get source FC_ID (S_ID) from frame header in message. */static inline u32 fc_frame_sid(const struct fc_frame *fp){	return ntoh24(__fc_frame_header_get(fp)->fh_s_id);} /* * Get destination FC_ID (D_ID) from frame header in message. */static inline u32 fc_frame_did(const struct fc_frame *fp){	return ntoh24(__fc_frame_header_get(fp)->fh_d_id);} /* * 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){	void *pp = NULL; 	if (fr_len(fp) >= sizeof(struct fc_frame_header) + len)		pp = fc_frame_header_get(fp) + 1;	return pp;} /* * 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){	u8 *cp; 	cp = fc_frame_payload_get(fp, sizeof(u8));	if (!cp)		return 0;	return *cp; } /* * Get FC class from frame. */static inline enum fc_class fc_frame_class(const struct fc_frame *fp){	return fc_sof_class(fr_sof(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){	return fc_frame_header_get(fp)->fh_r_ctl;} static inline bool fc_frame_is_cmd(const struct fc_frame *fp){	return fc_frame_rctl(fp) == FC_RCTL_DD_UNSOL_CMD;} /* * 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){	WARN_ON(r_ctl == 0);	fh->fh_r_ctl = r_ctl;	hton24(fh->fh_d_id, did);	hton24(fh->fh_s_id, sid);	fh->fh_type = type;	hton24(fh->fh_f_ctl, f_ctl);	fh->fh_cs_ctl = 0;	fh->fh_df_ctl = 0;	fh->fh_parm_offset = htonl(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){	struct fc_frame_header *fh; 	fh = fc_frame_header_get(fp);	__fc_fill_fc_hdr(fh, r_ctl, did, sid, type, f_ctl, parm_offset);}  #endif /* _FC_FRAME_H_ */