text: /*
   * This header file contains public constants and structures used by
   * the scsi code for linux.
   *
   * For documentation on the OPCODES, MESSAGES, and SENSE values,
   * please consult the SCSI standard.
   */
  #ifndef _SCSI_SCSI_H
  #define _SCSI_SCSI_H
  
  #include <linux/types.h>
  #include <linux/scatterlist.h>
  #include <linux/kernel.h>
  
  struct scsi_cmnd;
  
  enum scsi_timeouts {
  	SCSI_DEFAULT_EH_TIMEOUT		= 10 * HZ,
  };
  
  /*
   * The maximum number of SG segments that we will put inside a
   * scatterlist (unless chaining is used). Should ideally fit inside a
   * single page, to avoid a higher order allocation.  We could define this
   * to SG_MAX_SINGLE_ALLOC to pack correctly at the highest order.  The
   * minimum value is 32
   */
  #define SCSI_MAX_SG_SEGMENTS	128
  
  /*
   * Like SCSI_MAX_SG_SEGMENTS, but for archs that have sg chaining. This limit
   * is totally arbitrary, a setting of 2048 will get you at least 8mb ios.
   */
  #ifdef ARCH_HAS_SG_CHAIN
  #define SCSI_MAX_SG_CHAIN_SEGMENTS	2048
  #else
  #define SCSI_MAX_SG_CHAIN_SEGMENTS	SCSI_MAX_SG_SEGMENTS
  #endif
  
  /*
   * DIX-capable adapters effectively support infinite chaining for the
   * protection information scatterlist
   */
  #define SCSI_MAX_PROT_SG_SEGMENTS	0xFFFF
  
  /*
   * Special value for scanning to specify scanning or rescanning of all
   * possible channels, (target) ids, or luns on a given shost.
   */
  #define SCAN_WILD_CARD	~0
  
  /*
   *      SCSI opcodes
   */
  
  #define TEST_UNIT_READY       0x00
  #define REZERO_UNIT           0x01
  #define REQUEST_SENSE         0x03
  #define FORMAT_UNIT           0x04
  #define READ_BLOCK_LIMITS     0x05
  #define REASSIGN_BLOCKS       0x07
  #define INITIALIZE_ELEMENT_STATUS 0x07
  #define READ_6                0x08
  #define WRITE_6               0x0a
  #define SEEK_6                0x0b
  #define READ_REVERSE          0x0f
  #define WRITE_FILEMARKS       0x10
  #define SPACE                 0x11
  #define INQUIRY               0x12
  #define RECOVER_BUFFERED_DATA 0x14
  #define MODE_SELECT           0x15
  #define RESERVE               0x16
  #define RELEASE               0x17
  #define COPY                  0x18
  #define ERASE                 0x19
  #define MODE_SENSE            0x1a
  #define START_STOP            0x1b
  #define RECEIVE_DIAGNOSTIC    0x1c
  #define SEND_DIAGNOSTIC       0x1d
  #define ALLOW_MEDIUM_REMOVAL  0x1e
  
  #define READ_FORMAT_CAPACITIES 0x23
  #define SET_WINDOW            0x24
  #define READ_CAPACITY         0x25
  #define READ_10               0x28
  #define WRITE_10              0x2a
  #define SEEK_10               0x2b
  #define POSITION_TO_ELEMENT   0x2b
  #define WRITE_VERIFY          0x2e
  #define VERIFY                0x2f
  #define SEARCH_HIGH           0x30
  #define SEARCH_EQUAL          0x31
  #define SEARCH_LOW            0x32
  #define SET_LIMITS            0x33
  #define PRE_FETCH             0x34
  #define READ_POSITION         0x34
  #define SYNCHRONIZE_CACHE     0x35
  #define LOCK_UNLOCK_CACHE     0x36
  #define READ_DEFECT_DATA      0x37
  #define MEDIUM_SCAN           0x38
  #define COMPARE               0x39
  #define COPY_VERIFY           0x3a
  #define WRITE_BUFFER          0x3b
  #define READ_BUFFER           0x3c
  #define UPDATE_BLOCK          0x3d
  #define READ_LONG             0x3e
  #define WRITE_LONG            0x3f
  #define CHANGE_DEFINITION     0x40
  #define WRITE_SAME            0x41
  #define UNMAP		      0x42
  #define READ_TOC              0x43
  #define READ_HEADER           0x44
  #define GET_EVENT_STATUS_NOTIFICATION 0x4a
  #define LOG_SELECT            0x4c
  #define LOG_SENSE             0x4d
  #define XDWRITEREAD_10        0x53
  #define MODE_SELECT_10        0x55
  #define RESERVE_10            0x56
  #define RELEASE_10            0x57
  #define MODE_SENSE_10         0x5a
  #define PERSISTENT_RESERVE_IN 0x5e
  #define PERSISTENT_RESERVE_OUT 0x5f
  #define VARIABLE_LENGTH_CMD   0x7f
  #define REPORT_LUNS           0xa0
  #define SECURITY_PROTOCOL_IN  0xa2
  #define MAINTENANCE_IN        0xa3
  #define MAINTENANCE_OUT       0xa4
  #define MOVE_MEDIUM           0xa5
  #define EXCHANGE_MEDIUM       0xa6
  #define READ_12               0xa8
  #define WRITE_12              0xaa
  #define READ_MEDIA_SERIAL_NUMBER 0xab
  #define WRITE_VERIFY_12       0xae
  #define VERIFY_12	      0xaf
  #define SEARCH_HIGH_12        0xb0
  #define SEARCH_EQUAL_12       0xb1
  #define SEARCH_LOW_12         0xb2
  #define SECURITY_PROTOCOL_OUT 0xb5
  #define READ_ELEMENT_STATUS   0xb8
  #define SEND_VOLUME_TAG       0xb6
  #define WRITE_LONG_2          0xea
  #define EXTENDED_COPY         0x83
  #define RECEIVE_COPY_RESULTS  0x84
  #define ACCESS_CONTROL_IN     0x86
  #define ACCESS_CONTROL_OUT    0x87
  #define READ_16               0x88
  #define COMPARE_AND_WRITE     0x89
  #define WRITE_16              0x8a
  #define READ_ATTRIBUTE        0x8c
  #define WRITE_ATTRIBUTE	      0x8d
  #define VERIFY_16	      0x8f
  #define SYNCHRONIZE_CACHE_16  0x91
  #define WRITE_SAME_16	      0x93
  #define SERVICE_ACTION_IN     0x9e
  /* values for service action in */
  #define	SAI_READ_CAPACITY_16  0x10
  #define SAI_GET_LBA_STATUS    0x12
  /* values for VARIABLE_LENGTH_CMD service action codes
   * see spc4r17 Section D.3.5, table D.7 and D.8 */
  #define VLC_SA_RECEIVE_CREDENTIAL 0x1800
  /* values for maintenance in */
  #define MI_REPORT_IDENTIFYING_INFORMATION 0x05
  #define MI_REPORT_TARGET_PGS  0x0a
  #define MI_REPORT_ALIASES     0x0b
  #define MI_REPORT_SUPPORTED_OPERATION_CODES 0x0c
  #define MI_REPORT_SUPPORTED_TASK_MANAGEMENT_FUNCTIONS 0x0d
  #define MI_REPORT_PRIORITY   0x0e
  #define MI_REPORT_TIMESTAMP  0x0f
  #define MI_MANAGEMENT_PROTOCOL_IN 0x10
  /* value for MI_REPORT_TARGET_PGS ext header */
  #define MI_EXT_HDR_PARAM_FMT  0x20
  /* values for maintenance out */
  #define MO_SET_IDENTIFYING_INFORMATION 0x06
  #define MO_SET_TARGET_PGS     0x0a
  #define MO_CHANGE_ALIASES     0x0b
  #define MO_SET_PRIORITY       0x0e
  #define MO_SET_TIMESTAMP      0x0f
  #define MO_MANAGEMENT_PROTOCOL_OUT 0x10
  /* values for variable length command */
  #define XDREAD_32	      0x03
  #define XDWRITE_32	      0x04
  #define XPWRITE_32	      0x06
  #define XDWRITEREAD_32	      0x07
  #define READ_32		      0x09
  #define VERIFY_32	      0x0a
  #define WRITE_32	      0x0b
  #define WRITE_SAME_32	      0x0d
  
  /* Values for T10/04-262r7 */
  #define	ATA_16		      0x85	/* 16-byte pass-thru */
  #define	ATA_12		      0xa1	/* 12-byte pass-thru */
  
  /*
   *	SCSI command lengths
   */
  
  #define SCSI_MAX_VARLEN_CDB_SIZE 260
  
  /* defined in T10 SCSI Primary Commands-2 (SPC2) */
  struct scsi_varlen_cdb_hdr {
  	__u8 opcode;        /* opcode always == VARIABLE_LENGTH_CMD */
  	__u8 control;
  	__u8 misc[5];
  	__u8 additional_cdb_length;         /* total cdb length - 8 */
  	__be16 service_action;
  	/* service specific data follows */
  };
  
  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]);
  }
  
  #ifdef CONFIG_ACPI
  struct acpi_bus_type;
  
  extern int
  scsi_register_acpi_bus_type(struct acpi_bus_type *bus);
  
  extern void
  scsi_unregister_acpi_bus_type(struct acpi_bus_type *bus);
  #endif
  
  /*
   *  SCSI Architecture Model (SAM) Status codes. Taken from SAM-3 draft
   *  T10/1561-D Revision 4 Draft dated 7th November 2002.
   */
  #define SAM_STAT_GOOD            0x00
  #define SAM_STAT_CHECK_CONDITION 0x02
  #define SAM_STAT_CONDITION_MET   0x04
  #define SAM_STAT_BUSY            0x08
  #define SAM_STAT_INTERMEDIATE    0x10
  #define SAM_STAT_INTERMEDIATE_CONDITION_MET 0x14
  #define SAM_STAT_RESERVATION_CONFLICT 0x18
  #define SAM_STAT_COMMAND_TERMINATED 0x22	/* obsolete in SAM-3 */
  #define SAM_STAT_TASK_SET_FULL   0x28
  #define SAM_STAT_ACA_ACTIVE      0x30
  #define SAM_STAT_TASK_ABORTED    0x40
  
  /** scsi_status_is_good - check the status return.
   *
   * @status: the status passed up from the driver (including host and
   *          driver components)
   *
   * This returns true for known good conditions that may be treated as
   * command completed normally
   */
  static inline int scsi_status_is_good(int status)
  {
  	/*
  	 * FIXME: bit0 is listed as reserved in SCSI-2, but is
  	 * significant in SCSI-3.  For now, we follow the SCSI-2
  	 * behaviour and ignore reserved bits.
  	 */
  	status &= 0xfe;
  	return ((status == SAM_STAT_GOOD) ||
  		(status == SAM_STAT_INTERMEDIATE) ||
  		(status == SAM_STAT_INTERMEDIATE_CONDITION_MET) ||
  		/* FIXME: this is obsolete in SAM-3 */
  		(status == SAM_STAT_COMMAND_TERMINATED));
  }
  
  /*
   *  Status codes. These are deprecated as they are shifted 1 bit right
   *  from those found in the SCSI standards. This causes confusion for
   *  applications that are ported to several OSes. Prefer SAM Status codes
   *  above.
   */
  
  #define GOOD                 0x00
  #define CHECK_CONDITION      0x01
  #define CONDITION_GOOD       0x02
  #define BUSY                 0x04
  #define INTERMEDIATE_GOOD    0x08
  #define INTERMEDIATE_C_GOOD  0x0a
  #define RESERVATION_CONFLICT 0x0c
  #define COMMAND_TERMINATED   0x11
  #define QUEUE_FULL           0x14
  #define ACA_ACTIVE           0x18
  #define TASK_ABORTED         0x20
  
  #define STATUS_MASK          0xfe
  
  /*
   *  SENSE KEYS
   */
  
  #define NO_SENSE            0x00
  #define RECOVERED_ERROR     0x01
  #define NOT_READY           0x02
  #define MEDIUM_ERROR        0x03
  #define HARDWARE_ERROR      0x04
  #define ILLEGAL_REQUEST     0x05
  #define UNIT_ATTENTION      0x06
  #define DATA_PROTECT        0x07
  #define BLANK_CHECK         0x08
  #define COPY_ABORTED        0x0a
  #define ABORTED_COMMAND     0x0b
  #define VOLUME_OVERFLOW     0x0d
  #define MISCOMPARE          0x0e
  
  
  /*
   *  DEVICE TYPES
   *  Please keep them in 0x%02x format for $MODALIAS to work
   */
  
  #define TYPE_DISK           0x00
  #define TYPE_TAPE           0x01
  #define TYPE_PRINTER        0x02
  #define TYPE_PROCESSOR      0x03    /* HP scanners use this */
  #define TYPE_WORM           0x04    /* Treated as ROM by our system */
  #define TYPE_ROM            0x05
  #define TYPE_SCANNER        0x06
  #define TYPE_MOD            0x07    /* Magneto-optical disk - 
  				     * - treated as TYPE_DISK */
  #define TYPE_MEDIUM_CHANGER 0x08
  #define TYPE_COMM           0x09    /* Communications device */
  #define TYPE_RAID           0x0c
  #define TYPE_ENCLOSURE      0x0d    /* Enclosure Services Device */
  #define TYPE_RBC	    0x0e
  #define TYPE_OSD            0x11
  #define TYPE_NO_LUN         0x7f
  
  /* SCSI protocols; these are taken from SPC-3 section 7.5 */
  enum scsi_protocol {
  	SCSI_PROTOCOL_FCP = 0,	/* Fibre Channel */
  	SCSI_PROTOCOL_SPI = 1,	/* parallel SCSI */
  	SCSI_PROTOCOL_SSA = 2,	/* Serial Storage Architecture - Obsolete */
  	SCSI_PROTOCOL_SBP = 3,	/* firewire */
  	SCSI_PROTOCOL_SRP = 4,	/* Infiniband RDMA */
  	SCSI_PROTOCOL_ISCSI = 5,
  	SCSI_PROTOCOL_SAS = 6,
  	SCSI_PROTOCOL_ADT = 7,	/* Media Changers */
  	SCSI_PROTOCOL_ATA = 8,
  	SCSI_PROTOCOL_UNSPEC = 0xf, /* No specific protocol */
  };
  
  /* Returns a human-readable name for the device */
  extern const char * scsi_device_type(unsigned type);
  
  /*
   * standard mode-select header prepended to all mode-select commands
   */
  
  struct ccs_modesel_head {
  	__u8 _r1;			/* reserved */
  	__u8 medium;		/* device-specific medium type */
  	__u8 _r2;			/* reserved */
  	__u8 block_desc_length;	/* block descriptor length */
  	__u8 density;		/* device-specific density code */
  	__u8 number_blocks_hi;	/* number of blocks in this block desc */
  	__u8 number_blocks_med;
  	__u8 number_blocks_lo;
  	__u8 _r3;
  	__u8 block_length_hi;	/* block length for blocks in this desc */
  	__u8 block_length_med;
  	__u8 block_length_lo;
  };
  
  /*
   * ScsiLun: 8 byte LUN.
   */
  struct scsi_lun {
  	__u8 scsi_lun[8];
  };
  
  /*
   * The Well Known LUNS (SAM-3) in our int representation of a LUN
   */
  #define SCSI_W_LUN_BASE 0xc100
  #define SCSI_W_LUN_REPORT_LUNS (SCSI_W_LUN_BASE + 1)
  #define SCSI_W_LUN_ACCESS_CONTROL (SCSI_W_LUN_BASE + 2)
  #define SCSI_W_LUN_TARGET_LOG_PAGE (SCSI_W_LUN_BASE + 3)
  
  static inline int scsi_is_wlun(unsigned int lun)
  {
  	return (lun & 0xff00) == SCSI_W_LUN_BASE;
  }
  
  
  /*
   *  MESSAGE CODES
   */
  
  #define COMMAND_COMPLETE    0x00
  #define EXTENDED_MESSAGE    0x01
  #define     EXTENDED_MODIFY_DATA_POINTER    0x00
  #define     EXTENDED_SDTR                   0x01
  #define     EXTENDED_EXTENDED_IDENTIFY      0x02    /* SCSI-I only */
  #define     EXTENDED_WDTR                   0x03
  #define     EXTENDED_PPR                    0x04
  #define     EXTENDED_MODIFY_BIDI_DATA_PTR   0x05
  #define SAVE_POINTERS       0x02
  #define RESTORE_POINTERS    0x03
  #define DISCONNECT          0x04
  #define INITIATOR_ERROR     0x05
  #define ABORT_TASK_SET      0x06
  #define MESSAGE_REJECT      0x07
  #define NOP                 0x08
  #define MSG_PARITY_ERROR    0x09
  #define LINKED_CMD_COMPLETE 0x0a
  #define LINKED_FLG_CMD_COMPLETE 0x0b
  #define TARGET_RESET        0x0c
  #define ABORT_TASK          0x0d
  #define CLEAR_TASK_SET      0x0e
  #define INITIATE_RECOVERY   0x0f            /* SCSI-II only */
  #define RELEASE_RECOVERY    0x10            /* SCSI-II only */
  #define CLEAR_ACA           0x16
  #define LOGICAL_UNIT_RESET  0x17
  #define SIMPLE_QUEUE_TAG    0x20
  #define HEAD_OF_QUEUE_TAG   0x21
  #define ORDERED_QUEUE_TAG   0x22
  #define IGNORE_WIDE_RESIDUE 0x23
  #define ACA                 0x24
  #define QAS_REQUEST         0x55
  
  /* Old SCSI2 names, don't use in new code */
  #define BUS_DEVICE_RESET    TARGET_RESET
  #define ABORT               ABORT_TASK_SET
  
  /*
   * Host byte codes
   */
  
  #define DID_OK          0x00	/* NO error                                */
  #define DID_NO_CONNECT  0x01	/* Couldn't connect before timeout period  */
  #define DID_BUS_BUSY    0x02	/* BUS stayed busy through time out period */
  #define DID_TIME_OUT    0x03	/* TIMED OUT for other reason              */
  #define DID_BAD_TARGET  0x04	/* BAD target.                             */
  #define DID_ABORT       0x05	/* Told to abort for some other reason     */
  #define DID_PARITY      0x06	/* Parity error                            */
  #define DID_ERROR       0x07	/* Internal error                          */
  #define DID_RESET       0x08	/* Reset by somebody.                      */
  #define DID_BAD_INTR    0x09	/* Got an interrupt we weren't expecting.  */
  #define DID_PASSTHROUGH 0x0a	/* Force command past mid-layer            */
  #define DID_SOFT_ERROR  0x0b	/* The low level driver just wish a retry  */
  #define DID_IMM_RETRY   0x0c	/* Retry without decrementing retry count  */
  #define DID_REQUEUE	0x0d	/* Requeue command (no immediate retry) also
  				 * without decrementing the retry count	   */
  #define DID_TRANSPORT_DISRUPTED 0x0e /* Transport error disrupted execution
  				      * and the driver blocked the port to
  				      * recover the link. Transport class will
  				      * retry or fail IO */
  #define DID_TRANSPORT_FAILFAST	0x0f /* Transport class fastfailed the io */
  #define DID_TARGET_FAILURE 0x10 /* Permanent target failure, do not retry on
  				 * other paths */
  #define DID_NEXUS_FAILURE 0x11  /* Permanent nexus failure, retry on other
  				 * paths might yield different results */
  #define DID_ALLOC_FAILURE 0x12  /* Space allocation on the device failed */
  #define DID_MEDIUM_ERROR  0x13  /* Medium error */
  #define DRIVER_OK       0x00	/* Driver status                           */
  
  /*
   *  These indicate the error that occurred, and what is available.
   */
  
  #define DRIVER_BUSY         0x01
  #define DRIVER_SOFT         0x02
  #define DRIVER_MEDIA        0x03
  #define DRIVER_ERROR        0x04
  
  #define DRIVER_INVALID      0x05
  #define DRIVER_TIMEOUT      0x06
  #define DRIVER_HARD         0x07
  #define DRIVER_SENSE	    0x08
  
  /*
   * Internal return values.
   */
  
  #define NEEDS_RETRY     0x2001
  #define SUCCESS         0x2002
  #define FAILED          0x2003
  #define QUEUED          0x2004
  #define SOFT_ERROR      0x2005
  #define ADD_TO_MLQUEUE  0x2006
  #define TIMEOUT_ERROR   0x2007
  #define SCSI_RETURN_NOT_HANDLED   0x2008
  #define FAST_IO_FAIL	0x2009
  
  /*
   * Midlevel queue return values.
   */
  #define SCSI_MLQUEUE_HOST_BUSY   0x1055
  #define SCSI_MLQUEUE_DEVICE_BUSY 0x1056
  #define SCSI_MLQUEUE_EH_RETRY    0x1057
  #define SCSI_MLQUEUE_TARGET_BUSY 0x1058
  
  /*
   *  Use these to separate status msg and our bytes
   *
   *  These are set by:
   *
   *      status byte = set from target device
   *      msg_byte    = return status from host adapter itself.
   *      host_byte   = set by low-level driver to indicate status.
   *      driver_byte = set by mid-level.
   */
  #define status_byte(result) (((result) >> 1) & 0x7f)
  #define msg_byte(result)    (((result) >> 8) & 0xff)
  #define host_byte(result)   (((result) >> 16) & 0xff)
  #define driver_byte(result) (((result) >> 24) & 0xff)
  
  #define sense_class(sense)  (((sense) >> 4) & 0x7)
  #define sense_error(sense)  ((sense) & 0xf)
  #define sense_valid(sense)  ((sense) & 0x80)
  
  /*
   * default timeouts
  */
  #define FORMAT_UNIT_TIMEOUT		(2 * 60 * 60 * HZ)
  #define START_STOP_TIMEOUT		(60 * HZ)
  #define MOVE_MEDIUM_TIMEOUT		(5 * 60 * HZ)
  #define READ_ELEMENT_STATUS_TIMEOUT	(5 * 60 * HZ)
  #define READ_DEFECT_DATA_TIMEOUT	(60 * HZ )
  
  
  #define IDENTIFY_BASE       0x80
  #define IDENTIFY(can_disconnect, lun)   (IDENTIFY_BASE |\
  		     ((can_disconnect) ?  0x40 : 0) |\
  		     ((lun) & 0x07))
  
  /*
   *  struct scsi_device::scsi_level values. For SCSI devices other than those
   *  prior to SCSI-2 (i.e. over 12 years old) this value is (resp[2] + 1)
   *  where "resp" is a byte array of the response to an INQUIRY. The scsi_level
   *  variable is visible to the user via sysfs.
   */
  
  #define SCSI_UNKNOWN    0
  #define SCSI_1          1
  #define SCSI_1_CCS      2
  #define SCSI_2          3
  #define SCSI_3          4        /* SPC */
  #define SCSI_SPC_2      5
  #define SCSI_SPC_3      6
  
  /*
   * INQ PERIPHERAL QUALIFIERS
   */
  #define SCSI_INQ_PQ_CON         0x00
  #define SCSI_INQ_PQ_NOT_CON     0x01
  #define SCSI_INQ_PQ_NOT_CAP     0x03
  
  
  /*
   * Here are some scsi specific ioctl commands which are sometimes useful.
   *
   * Note that include/linux/cdrom.h also defines IOCTL 0x5300 - 0x5395
   */
  
  /* Used to obtain PUN and LUN info.  Conflicts with CDROMAUDIOBUFSIZ */
  #define SCSI_IOCTL_GET_IDLUN		0x5382
  
  /* 0x5383 and 0x5384 were used for SCSI_IOCTL_TAGGED_{ENABLE,DISABLE} */
  
  /* Used to obtain the host number of a device. */
  #define SCSI_IOCTL_PROBE_HOST		0x5385
  
  /* Used to obtain the bus number for a device */
  #define SCSI_IOCTL_GET_BUS_NUMBER	0x5386
  
  /* Used to obtain the PCI location of a device */
  #define SCSI_IOCTL_GET_PCI		0x5387
  
  /* Pull a u32 out of a SCSI message (using BE SCSI conventions) */
  static inline __u32 scsi_to_u32(__u8 *ptr)
  {
  	return (ptr[0]<<24) + (ptr[1]<<16) + (ptr[2]<<8) + ptr[3];
  }
  
  #endif /* _SCSI_SCSI_H */
  