Edit File: fc_frame.h
/* * Copyright(c) 2007 Intel Corporation. All rights reserved. * * This program is free software; you can redistribute it and/or modify it * under the terms and conditions of the GNU General Public License, * version 2, as published by the Free Software Foundation. * * This program is distributed in the hope it will be useful, but WITHOUT * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for * more details. * * You should have received a copy of the GNU General Public License along with * this program; if not, write to the Free Software Foundation, Inc., * 51 Franklin St - Fifth Floor, Boston, MA 02110-1301 USA. * * 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 inline struct 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 inline struct 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); #endif /* _FC_FRAME_H_ */