include/scsi/scsi.h - kernel/msm - Gitiles

 /*
  * 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/device.h>

 struct scsi_cmnd;

 /*
  * 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 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
 /* 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]);
 }

 /*
  *  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 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
 #define TARGET_ERROR    0x200A

 /*
  * 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];
 }

 struct scsi_disk *scsi_disk_get_from_dev(struct device *dev);

 #endif /* _SCSI_SCSI_H */
	/*
	* 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/device.h>

	struct scsi_cmnd;

	/*
	* 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 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
	/* 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]);
	}

	/*
	* 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 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
	#define TARGET_ERROR 0x200A

	/*
	* 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];
	}

	struct scsi_disk scsi_disk_get_from_dev(struct device dev);

	#endif /* _SCSI_SCSI_H */