Move code that is used both by initiator and target drivers

Move the functions that are used by both the initiator and target
subsystems into scsi_common.c/.h. This change will allow to remove
the initiator SCSI header include directives from most SCSI target
source files in a later patch.

Signed-off-by: Bart Van Assche <bart.vanassche@sandisk.com>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: James Bottomley <JBottomley@Odin.com>

1 files changed, 64 insertions, 0 deletions

diff --git a/include/scsi/scsi_common.h b/include/scsi/scsi_common.h
new file mode 100644
index 000000000000..676b03b78e57
--- /dev/null
+++ b/include/scsi/scsi_common.h
@@ -0,0 +1,64 @@
+/*
+ * Functions used by both the SCSI initiator code and the SCSI target code.
+ */
+
+#ifndef _SCSI_COMMON_H_
+#define _SCSI_COMMON_H_
+
+#include <linux/types.h>
+#include <scsi/scsi_proto.h>
+
+static inline unsigned
+scsi_varlen_cdb_length(const void *hdr)
+{
+	return ((struct scsi_varlen_cdb_hdr *)hdr)->additional_cdb_length + 8;
+}
+
+extern const unsigned char scsi_command_size_tbl[8];
+#define COMMAND_SIZE(opcode) scsi_command_size_tbl[((opcode) >> 5) & 7]
+
+static inline unsigned
+scsi_command_size(const unsigned char *cmnd)
+{
+	return (cmnd[0] == VARIABLE_LENGTH_CMD) ?
+		scsi_varlen_cdb_length(cmnd) : COMMAND_SIZE(cmnd[0]);
+}
+
+/* Returns a human-readable name for the device */
+extern const char *scsi_device_type(unsigned type);
+
+extern void int_to_scsilun(u64, struct scsi_lun *);
+extern u64 scsilun_to_int(struct scsi_lun *);
+
+/*
+ * This is a slightly modified SCSI sense "descriptor" format header.
+ * The addition is to allow the 0x70 and 0x71 response codes. The idea
+ * is to place the salient data from either "fixed" or "descriptor" sense
+ * format into one structure to ease application processing.
+ *
+ * The original sense buffer should be kept around for those cases
+ * in which more information is required (e.g. the LBA of a MEDIUM ERROR).
+ */
+struct scsi_sense_hdr {		/* See SPC-3 section 4.5 */
+	u8 response_code;	/* permit: 0x0, 0x70, 0x71, 0x72, 0x73 */
+	u8 sense_key;
+	u8 asc;
+	u8 ascq;
+	u8 byte4;
+	u8 byte5;
+	u8 byte6;
+	u8 additional_length;	/* always 0 for fixed sense format */
+};
+
+static inline bool scsi_sense_valid(const struct scsi_sense_hdr *sshdr)
+{
+	if (!sshdr)
+		return false;
+
+	return (sshdr->response_code & 0x70) == 0x70;
+}
+
+extern bool scsi_normalize_sense(const u8 *sense_buffer, int sb_len,
+				 struct scsi_sense_hdr *sshdr);
+
+#endif /* _SCSI_COMMON_H_ */