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Diffstat (limited to 'include/scsi/fc/fc_encaps.h')
-rw-r--r-- | include/scsi/fc/fc_encaps.h | 126 |
1 files changed, 126 insertions, 0 deletions
diff --git a/include/scsi/fc/fc_encaps.h b/include/scsi/fc/fc_encaps.h new file mode 100644 index 000000000..4261e609c --- /dev/null +++ b/include/scsi/fc/fc_encaps.h @@ -0,0 +1,126 @@ +/* SPDX-License-Identifier: GPL-2.0-only */ +/* + * Copyright(c) 2007 Intel Corporation. All rights reserved. + * + * Maintained at www.Open-FCoE.org + */ +#ifndef _FC_ENCAPS_H_ +#define _FC_ENCAPS_H_ + +/* + * Protocol definitions from RFC 3643 - Fibre Channel Frame Encapsulation. + * + * Note: The frame length field is the number of 32-bit words in + * the encapsulation including the fcip_encaps_header, CRC and EOF words. + * The minimum frame length value in bytes is (32 + 24 + 4 + 4) * 4 = 64. + * The maximum frame length value in bytes is (32 + 24 + 2112 + 4 + 4) = 2172. + */ +#define FC_ENCAPS_MIN_FRAME_LEN 64 /* min frame len (bytes) (see above) */ +#define FC_ENCAPS_MAX_FRAME_LEN (FC_ENCAPS_MIN_FRAME_LEN + FC_MAX_PAYLOAD) + +#define FC_ENCAPS_VER 1 /* current version number */ + +struct fc_encaps_hdr { + __u8 fc_proto; /* protocol number */ + __u8 fc_ver; /* version of encapsulation */ + __u8 fc_proto_n; /* ones complement of protocol */ + __u8 fc_ver_n; /* ones complement of version */ + + unsigned char fc_proto_data[8]; /* protocol specific data */ + + __be16 fc_len_flags; /* 10-bit length/4 w/ 6 flag bits */ + __be16 fc_len_flags_n; /* ones complement of length / flags */ + + /* + * Offset 0x10 + */ + __be32 fc_time[2]; /* time stamp: seconds and fraction */ + __be32 fc_crc; /* CRC */ + __be32 fc_sof; /* start of frame (see FC_SOF below) */ + + /* 0x20 - FC frame content followed by EOF word */ +}; + +#define FCIP_ENCAPS_HDR_LEN 0x20 /* expected length for asserts */ + +/* + * Macro's for making redundant copies of EOF and SOF. + */ +#define FC_XY(x, y) ((((x) & 0xff) << 8) | ((y) & 0xff)) +#define FC_XYXY(x, y) ((FCIP_XY(x, y) << 16) | FCIP_XY(x, y)) +#define FC_XYNN(x, y) (FCIP_XYXY(x, y) ^ 0xffff) + +#define FC_SOF_ENCODE(n) FC_XYNN(n, n) +#define FC_EOF_ENCODE(n) FC_XYNN(n, n) + +/* + * SOF / EOF bytes. + */ +enum fc_sof { + FC_SOF_F = 0x28, /* fabric */ + FC_SOF_I4 = 0x29, /* initiate class 4 */ + FC_SOF_I2 = 0x2d, /* initiate class 2 */ + FC_SOF_I3 = 0x2e, /* initiate class 3 */ + FC_SOF_N4 = 0x31, /* normal class 4 */ + FC_SOF_N2 = 0x35, /* normal class 2 */ + FC_SOF_N3 = 0x36, /* normal class 3 */ + FC_SOF_C4 = 0x39, /* activate class 4 */ +} __attribute__((packed)); + +enum fc_eof { + FC_EOF_N = 0x41, /* normal (not last frame of seq) */ + FC_EOF_T = 0x42, /* terminate (last frame of sequence) */ + FC_EOF_RT = 0x44, + FC_EOF_DT = 0x46, /* disconnect-terminate class-1 */ + FC_EOF_NI = 0x49, /* normal-invalid */ + FC_EOF_DTI = 0x4e, /* disconnect-terminate-invalid */ + FC_EOF_RTI = 0x4f, + FC_EOF_A = 0x50, /* abort */ +} __attribute__((packed)); + +#define FC_SOF_CLASS_MASK 0x06 /* mask for class of service in SOF */ + +/* + * Define classes in terms of the SOF code (initial). + */ +enum fc_class { + FC_CLASS_NONE = 0, /* software value indicating no class */ + FC_CLASS_2 = FC_SOF_I2, + FC_CLASS_3 = FC_SOF_I3, + FC_CLASS_4 = FC_SOF_I4, + FC_CLASS_F = FC_SOF_F, +}; + +/* + * Determine whether SOF code indicates the need for a BLS ACK. + */ +static inline int fc_sof_needs_ack(enum fc_sof sof) +{ + return (~sof) & 0x02; /* true for class 1, 2, 4, 6, or F */ +} + +/* + * Given an fc_class, return the normal (non-initial) SOF value. + */ +static inline enum fc_sof fc_sof_normal(enum fc_class class) +{ + return class + FC_SOF_N3 - FC_SOF_I3; /* diff is always 8 */ +} + +/* + * Compute class from SOF value. + */ +static inline enum fc_class fc_sof_class(enum fc_sof sof) +{ + return (sof & 0x7) | FC_SOF_F; +} + +/* + * Determine whether SOF is for the initial frame of a sequence. + */ +static inline int fc_sof_is_init(enum fc_sof sof) +{ + return sof < 0x30; +} + +#endif /* _FC_ENCAPS_H_ */ |