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-rw-r--r--include/scsi/fc_frame.h242
1 files changed, 242 insertions, 0 deletions
diff --git a/include/scsi/fc_frame.h b/include/scsi/fc_frame.h
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--- /dev/null
+++ b/include/scsi/fc_frame.h
@@ -0,0 +1,242 @@
+/*
+ * 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>
+
+/*
+ * 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 */
+
+/*
+ * Information about an individual fibre channel frame received or to be sent.
+ * The buffer may be in up to 4 additional non-contiguous sections,
+ * but the linear section must hold the frame header.
+ */
+#define FC_FRAME_SG_LEN 4 /* scatter/gather list maximum length */
+
+#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_max_payload(fp) (fr_cb(fp)->fr_max_payload)
+#define fr_cmd(fp) (fr_cb(fp)->fr_cmd)
+#define fr_dir(fp) (fr_cmd(fp)->sc_data_direction)
+#define fr_crc(fp) (fr_cb(fp)->fr_crc)
+
+struct fc_frame {
+ struct sk_buff skb;
+};
+
+struct fcoe_rcv_info {
+ struct packet_type *ptype;
+ struct fc_lport *fr_dev; /* transport layer private pointer */
+ struct fc_seq *fr_seq; /* for use with exchange manager */
+ struct scsi_cmnd *fr_cmd; /* for use of scsi command */
+ u32 fr_crc;
+ u16 fr_max_payload; /* max FC payload */
+ enum fc_sof fr_sof; /* start of frame delimiter */
+ enum fc_eof fr_eof; /* end of frame delimiter */
+ u8 fr_flags; /* flags - see below */
+};
+
+
+/*
+ * 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;
+}
+
+struct fc_frame *fc_frame_alloc_fill(struct fc_lport *, size_t payload_len);
+
+struct fc_frame *__fc_frame_alloc(size_t payload_len);
+
+/*
+ * Get frame for sending via port.
+ */
+static inline struct fc_frame *_fc_frame_alloc(struct fc_lport *dev,
+ size_t payload_len)
+{
+ return __fc_frame_alloc(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 % 4) != 0)
+ fp = fc_frame_alloc_fill(dev, len);
+ else
+ fp = _fc_frame_alloc(dev, 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 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 (struct fc_frame_header *) fr_hdr(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)
+{
+ 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;
+}
+
+static inline bool fc_frame_is_read(const struct fc_frame *fp)
+{
+ if (fc_frame_is_cmd(fp) && fr_cmd(fp))
+ return fr_dir(fp) == DMA_FROM_DEVICE;
+ return false;
+}
+
+static inline bool fc_frame_is_write(const struct fc_frame *fp)
+{
+ if (fc_frame_is_cmd(fp) && fr_cmd(fp))
+ return fr_dir(fp) == DMA_TO_DEVICE;
+ return false;
+}
+
+/*
+ * 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_ */
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