diff --git a/include/scsi/sg.h b/include/scsi/sg.h
index f91bcca604e4..596f68746f66 100644
--- a/include/scsi/sg.h
+++ b/include/scsi/sg.h
@@ -7,23 +7,23 @@
 /*
  * History:
  *  Started: Aug 9 by Lawrence Foard (entropy@world.std.com), to allow user
- *   process control of SCSI devices.
+ *  process control of SCSI devices.
  *  Development Sponsored by Killy Corp. NY NY
  *
  * Original driver (sg.h):
- *       Copyright (C) 1992 Lawrence Foard
+ *   Copyright (C) 1992 Lawrence Foard
  * Version 2 and 3 extensions to driver:
- *	Copyright (C) 1998 - 2014 Douglas Gilbert
+ *   Copyright (C) 1998 - 2018 Douglas Gilbert
  *
- *  Version: 3.5.36 (20140603)
- *  This version is for 2.6 and 3 series kernels.
+ *  Version: 3.9.01 (20181016)
+ *  This version is for 2.6, 3 and 4 series kernels.
  *
  * Documentation
  * =============
  * A web site for the SG device driver can be found at:
- *	http://sg.danny.cz/sg  [alternatively check the MAINTAINERS file]
+ *   http://sg.danny.cz/sg  [alternatively check the MAINTAINERS file]
  * The documentation for the sg version 3 driver can be found at:
- *	http://sg.danny.cz/sg/p/sg_v3_ho.html
+ *   http://sg.danny.cz/sg/p/sg_v3_ho.html
  * Also see: <kernel_source>/Documentation/scsi/scsi-generic.txt
  *
  * For utility and test programs see: http://sg.danny.cz/sg/sg3_utils.html
@@ -33,242 +33,12 @@
 extern int sg_big_buff; /* for sysctl */
 #endif
 
+#include <uapi/scsi/sg.h>
 
-typedef struct sg_iovec /* same structure as used by readv() Linux system */
-{                       /* call. It defines one scatter-gather element. */
-    void __user *iov_base;      /* Starting address  */
-    size_t iov_len;             /* Length in bytes  */
-} sg_iovec_t;
-
-
-typedef struct sg_io_hdr
-{
-    int interface_id;           /* [i] 'S' for SCSI generic (required) */
-    int dxfer_direction;        /* [i] data transfer direction  */
-    unsigned char cmd_len;      /* [i] SCSI command length */
-    unsigned char mx_sb_len;    /* [i] max length to write to sbp */
-    unsigned short iovec_count; /* [i] 0 implies no scatter gather */
-    unsigned int dxfer_len;     /* [i] byte count of data transfer */
-    void __user *dxferp;	/* [i], [*io] points to data transfer memory
-					      or scatter gather list */
-    unsigned char __user *cmdp; /* [i], [*i] points to command to perform */
-    void __user *sbp;		/* [i], [*o] points to sense_buffer memory */
-    unsigned int timeout;       /* [i] MAX_UINT->no timeout (unit: millisec) */
-    unsigned int flags;         /* [i] 0 -> default, see SG_FLAG... */
-    int pack_id;                /* [i->o] unused internally (normally) */
-    void __user * usr_ptr;      /* [i->o] unused internally */
-    unsigned char status;       /* [o] scsi status */
-    unsigned char masked_status;/* [o] shifted, masked scsi status */
-    unsigned char msg_status;   /* [o] messaging level data (optional) */
-    unsigned char sb_len_wr;    /* [o] byte count actually written to sbp */
-    unsigned short host_status; /* [o] errors from host adapter */
-    unsigned short driver_status;/* [o] errors from software driver */
-    int resid;                  /* [o] dxfer_len - actual_transferred */
-    unsigned int duration;      /* [o] time taken by cmd (unit: millisec) */
-    unsigned int info;          /* [o] auxiliary information */
-} sg_io_hdr_t;  /* 64 bytes long (on i386) */
-
-#define SG_INTERFACE_ID_ORIG 'S'
-
-/* Use negative values to flag difference from original sg_header structure */
-#define SG_DXFER_NONE (-1)      /* e.g. a SCSI Test Unit Ready command */
-#define SG_DXFER_TO_DEV (-2)    /* e.g. a SCSI WRITE command */
-#define SG_DXFER_FROM_DEV (-3)  /* e.g. a SCSI READ command */
-#define SG_DXFER_TO_FROM_DEV (-4) /* treated like SG_DXFER_FROM_DEV with the
-				   additional property than during indirect
-				   IO the user buffer is copied into the
-				   kernel buffers before the transfer */
-#define SG_DXFER_UNKNOWN (-5)   /* Unknown data direction */
-
-/* following flag values can be "or"-ed together */
-#define SG_FLAG_DIRECT_IO 1     /* default is indirect IO */
-#define SG_FLAG_UNUSED_LUN_INHIBIT 2   /* default is overwrite lun in SCSI */
-				/* command block (when <= SCSI_2) */
-#define SG_FLAG_MMAP_IO 4       /* request memory mapped IO */
-#define SG_FLAG_NO_DXFER 0x10000 /* no transfer of kernel buffers to/from */
-				/* user space (debug indirect IO) */
-/* defaults:: for sg driver: Q_AT_HEAD; for block layer: Q_AT_TAIL */
-#define SG_FLAG_Q_AT_TAIL 0x10
-#define SG_FLAG_Q_AT_HEAD 0x20
-
-/* following 'info' values are "or"-ed together */
-#define SG_INFO_OK_MASK 0x1
-#define SG_INFO_OK 0x0          /* no sense, host nor driver "noise" */
-#define SG_INFO_CHECK 0x1       /* something abnormal happened */
-
-#define SG_INFO_DIRECT_IO_MASK 0x6
-#define SG_INFO_INDIRECT_IO 0x0 /* data xfer via kernel buffers (or no xfer) */
-#define SG_INFO_DIRECT_IO 0x2   /* direct IO requested and performed */
-#define SG_INFO_MIXED_IO 0x4    /* part direct, part indirect IO */
-
-
-typedef struct sg_scsi_id { /* used by SG_GET_SCSI_ID ioctl() */
-    int host_no;        /* as in "scsi<n>" where 'n' is one of 0, 1, 2 etc */
-    int channel;
-    int scsi_id;        /* scsi id of target device */
-    int lun;
-    int scsi_type;      /* TYPE_... defined in scsi/scsi.h */
-    short h_cmd_per_lun;/* host (adapter) maximum commands per lun */
-    short d_queue_depth;/* device (or adapter) maximum queue length */
-    int unused[2];      /* probably find a good use, set 0 for now */
-} sg_scsi_id_t; /* 32 bytes long on i386 */
-
-typedef struct sg_req_info { /* used by SG_GET_REQUEST_TABLE ioctl() */
-    char req_state;     /* 0 -> not used, 1 -> written, 2 -> ready to read */
-    char orphan;        /* 0 -> normal request, 1 -> from interruped SG_IO */
-    char sg_io_owned;   /* 0 -> complete with read(), 1 -> owned by SG_IO */
-    char problem;       /* 0 -> no problem detected, 1 -> error to report */
-    int pack_id;        /* pack_id associated with request */
-    void __user *usr_ptr;     /* user provided pointer (in new interface) */
-    unsigned int duration; /* millisecs elapsed since written (req_state==1)
-			      or request duration (req_state==2) */
-    int unused;
-} sg_req_info_t; /* 20 bytes long on i386 */
-
-
-/* IOCTLs: Those ioctls that are relevant to the SG 3.x drivers follow.
- [Those that only apply to the SG 2.x drivers are at the end of the file.]
- (_GET_s yield result via 'int *' 3rd argument unless otherwise indicated) */
-
-#define SG_EMULATED_HOST 0x2203 /* true for emulated host adapter (ATAPI) */
-
-/* Used to configure SCSI command transformation layer for ATAPI devices */
-/* Only supported by the ide-scsi driver */
-#define SG_SET_TRANSFORM 0x2204 /* N.B. 3rd arg is not pointer but value: */
-		      /* 3rd arg = 0 to disable transform, 1 to enable it */
-#define SG_GET_TRANSFORM 0x2205
-
-#define SG_SET_RESERVED_SIZE 0x2275  /* request a new reserved buffer size */
-#define SG_GET_RESERVED_SIZE 0x2272  /* actual size of reserved buffer */
-
-/* The following ioctl has a 'sg_scsi_id_t *' object as its 3rd argument. */
-#define SG_GET_SCSI_ID 0x2276   /* Yields fd's bus, chan, dev, lun + type */
-/* SCSI id information can also be obtained from SCSI_IOCTL_GET_IDLUN */
-
-/* Override host setting and always DMA using low memory ( <16MB on i386) */
-#define SG_SET_FORCE_LOW_DMA 0x2279  /* 0-> use adapter setting, 1-> force */
-#define SG_GET_LOW_DMA 0x227a   /* 0-> use all ram for dma; 1-> low dma ram */
-
-/* When SG_SET_FORCE_PACK_ID set to 1, pack_id is input to read() which
-   tries to fetch a packet with a matching pack_id, waits, or returns EAGAIN.
-   If pack_id is -1 then read oldest waiting. When ...FORCE_PACK_ID set to 0
-   then pack_id ignored by read() and oldest readable fetched. */
-#define SG_SET_FORCE_PACK_ID 0x227b
-#define SG_GET_PACK_ID 0x227c /* Yields oldest readable pack_id (or -1) */
-
-#define SG_GET_NUM_WAITING 0x227d /* Number of commands awaiting read() */
-
-/* Yields max scatter gather tablesize allowed by current host adapter */
-#define SG_GET_SG_TABLESIZE 0x227F  /* 0 implies can't do scatter gather */
-
-#define SG_GET_VERSION_NUM 0x2282 /* Example: version 2.1.34 yields 20134 */
-
-/* Returns -EBUSY if occupied. 3rd argument pointer to int (see next) */
-#define SG_SCSI_RESET 0x2284
-/* Associated values that can be given to SG_SCSI_RESET follow.
- * SG_SCSI_RESET_NO_ESCALATE may be OR-ed to the _DEVICE, _TARGET, _BUS
- * or _HOST reset value so only that action is attempted. */
-#define		SG_SCSI_RESET_NOTHING	0
-#define		SG_SCSI_RESET_DEVICE	1
-#define		SG_SCSI_RESET_BUS	2
-#define		SG_SCSI_RESET_HOST	3
-#define		SG_SCSI_RESET_TARGET	4
-#define		SG_SCSI_RESET_NO_ESCALATE	0x100
-
-/* synchronous SCSI command ioctl, (only in version 3 interface) */
-#define SG_IO 0x2285   /* similar effect as write() followed by read() */
-
-#define SG_GET_REQUEST_TABLE 0x2286   /* yields table of active requests */
-
-/* How to treat EINTR during SG_IO ioctl(), only in SG 3.x series */
-#define SG_SET_KEEP_ORPHAN 0x2287 /* 1 -> hold for read(), 0 -> drop (def) */
-#define SG_GET_KEEP_ORPHAN 0x2288
-
-/* yields scsi midlevel's access_count for this SCSI device */
-#define SG_GET_ACCESS_COUNT 0x2289  
-
-
-#define SG_SCATTER_SZ (8 * 4096)
-/* Largest size (in bytes) a single scatter-gather list element can have.
-   The value used by the driver is 'max(SG_SCATTER_SZ, PAGE_SIZE)'.
-   This value should be a power of 2 (and may be rounded up internally).
-   If scatter-gather is not supported by adapter then this value is the
-   largest data block that can be read/written by a single scsi command. */
-
-#define SG_DEFAULT_RETRIES 0
-
-/* Defaults, commented if they differ from original sg driver */
-#define SG_DEF_FORCE_PACK_ID 0
-#define SG_DEF_KEEP_ORPHAN 0
-#define SG_DEF_RESERVED_SIZE SG_SCATTER_SZ /* load time option */
-
-/* maximum outstanding requests, write() yields EDOM if exceeded */
-#define SG_MAX_QUEUE 16
-
-#define SG_BIG_BUFF SG_DEF_RESERVED_SIZE    /* for backward compatibility */
-
-/* Alternate style type names, "..._t" variants preferred */
-typedef struct sg_io_hdr Sg_io_hdr;
-typedef struct sg_io_vec Sg_io_vec;
-typedef struct sg_scsi_id Sg_scsi_id;
-typedef struct sg_req_info Sg_req_info;
-
-
-/* vvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvv */
-/*   The older SG interface based on the 'sg_header' structure follows.   */
-/* ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ */
-
-#define SG_MAX_SENSE 16   /* this only applies to the sg_header interface */
-
-struct sg_header
-{
-    int pack_len;    /* [o] reply_len (ie useless), ignored as input */
-    int reply_len;   /* [i] max length of expected reply (inc. sg_header) */
-    int pack_id;     /* [io] id number of packet (use ints >= 0) */
-    int result;      /* [o] 0==ok, else (+ve) Unix errno (best ignored) */
-    unsigned int twelve_byte:1;
-	/* [i] Force 12 byte command length for group 6 & 7 commands  */
-    unsigned int target_status:5;   /* [o] scsi status from target */
-    unsigned int host_status:8;     /* [o] host status (see "DID" codes) */
-    unsigned int driver_status:8;   /* [o] driver status+suggestion */
-    unsigned int other_flags:10;    /* unused */
-    unsigned char sense_buffer[SG_MAX_SENSE]; /* [o] Output in 3 cases:
-	   when target_status is CHECK_CONDITION or
-	   when target_status is COMMAND_TERMINATED or
-	   when (driver_status & DRIVER_SENSE) is true. */
-};      /* This structure is 36 bytes long on i386 */
-
-
-/* IOCTLs: The following are not required (or ignored) when the sg_io_hdr_t
-	   interface is used. They are kept for backward compatibility with
-	   the original and version 2 drivers. */
-
-#define SG_SET_TIMEOUT 0x2201  /* unit: jiffies (10ms on i386) */
-#define SG_GET_TIMEOUT 0x2202  /* yield timeout as _return_ value */
-
-/* Get/set command queuing state per fd (default is SG_DEF_COMMAND_Q.
-   Each time a sg_io_hdr_t object is seen on this file descriptor, this
-   command queuing flag is set on (overriding the previous setting). */
-#define SG_GET_COMMAND_Q 0x2270   /* Yields 0 (queuing off) or 1 (on) */
-#define SG_SET_COMMAND_Q 0x2271   /* Change queuing state with 0 or 1 */
-
-/* Turn on/off error sense trace (1 and 0 respectively, default is off).
-   Try using: "# cat /proc/scsi/sg/debug" instead in the v3 driver */
-#define SG_SET_DEBUG 0x227e    /* 0 -> turn off debug */
-
-#define SG_NEXT_CMD_LEN 0x2283  /* override SCSI command length with given
-		   number on the next write() on this file descriptor */
-
-
-/* Defaults, commented if they differ from original sg driver */
 #ifdef __KERNEL__
-#define SG_DEFAULT_TIMEOUT_USER	(60*USER_HZ) /* HZ == 'jiffies in 1 second' */
-#else
-#define SG_DEFAULT_TIMEOUT	(60*HZ)	     /* HZ == 'jiffies in 1 second' */
+#define SG_DEFAULT_TIMEOUT_USER (60*USER_HZ) /* HZ == 'jiffies in 1 second' */
 #endif
 
-#define SG_DEF_COMMAND_Q 0     /* command queuing is always on when
-				  the new interface is used */
-#define SG_DEF_UNDERRUN_FLAG 0
+#undef SG_DEFAULT_TIMEOUT	/* cause define in sg.c */
 
-#endif
+#endif	/* end of ifndef _SCSI_GENERIC_H guard */
diff --git a/include/uapi/scsi/sg.h b/include/uapi/scsi/sg.h
new file mode 100644
index 000000000000..0bc652402bd9
--- /dev/null
+++ b/include/uapi/scsi/sg.h
@@ -0,0 +1,418 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+#ifndef _UAPI_SCSI_SG_H
+#define _UAPI_SCSI_SG_H
+
+/*
+ * Want to block the original sg.h header from also being included. That
+ * causes lots of multiple definition errors. This will only work if this
+ * header is included _before_ the original sg.h header .
+ */
+#define _SCSI_GENERIC_H		/* original kernel header guard */
+#define _SCSI_SG_H		/* glibc header guard */
+
+/*
+ * Other UAPI headers include linux/compiler.h to resolve "__" types but that
+ * doesn't always work, perhaps in the future. Fall back to linux/types.h .
+ */
+/* #include <linux/compiler.h> */
+#include <linux/types.h>
+#include <linux/major.h>
+
+/* Still problems with __user so define to nothing */
+#define __user
+
+#include <linux/bsg.h>
+
+/*
+ * History:
+ *  Started: Aug 9 by Lawrence Foard (entropy@world.std.com), to allow user
+ *  process control of SCSI devices.
+ *  Development Sponsored by Killy Corp. NY NY
+ *
+ * Original driver (sg.h):
+ *   Copyright (C) 1992 Lawrence Foard
+ * Version 2 and 3 extensions to driver:
+ *   Copyright (C) 1998 - 2018 Douglas Gilbert
+ *
+ *  Version: 3.9.01 (20181014)
+ *  This version is for Linux 2.6, 3 and 4 series kernels.
+ *
+ * Documentation
+ * =============
+ * A web site for the SG device driver can be found at:
+ *   http://sg.danny.cz/sg  [alternatively check the MAINTAINERS file]
+ * The documentation for the sg version 3 driver can be found at:
+ *   http://sg.danny.cz/sg/p/sg_v3_ho.html
+ * Also see: <kernel_source>/Documentation/scsi/scsi-generic.txt
+ *
+ * For utility and test programs see: http://sg.danny.cz/sg/sg3_utils.html
+ */
+
+
+/*
+ * Same structure as used by readv() call. It defines one scatter-gather
+ * element. "Scatter-gather" is abbreviated to "sgat" in thsi driver to
+ * avoid confusion with this driver's name.
+ */
+typedef struct sg_iovec	{
+	void __user *iov_base;	/* Starting address (of a byte) */
+	size_t iov_len;		/* Length in bytes */
+} sg_iovec_t;
+
+
+typedef struct sg_io_hdr {
+	int interface_id;	/* [i] 'S' for SCSI generic (required) */
+	int dxfer_direction;	/* [i] data transfer direction  */
+	unsigned char cmd_len;	/* [i] SCSI command length */
+	unsigned char mx_sb_len;/* [i] max length to write to sbp */
+	unsigned short iovec_count;	/* [i] 0 implies no scatter gather */
+	unsigned int dxfer_len;	/* [i] byte count of data transfer */
+	/* points to data transfer memory or scatter gather list */
+	void __user *dxferp;	/* [i], [*io] */
+	unsigned char __user *cmdp;/* [i], [*i] points to command to perform */
+	void __user *sbp;	/* [i], [*o] points to sense_buffer memory */
+	unsigned int timeout;	/* [i] MAX_UINT->no timeout (unit: millisec) */
+	unsigned int flags;	/* [i] 0 -> default, see SG_FLAG... */
+	int pack_id;		/* [i->o] unused internally (normally) */
+	void __user *usr_ptr;	/* [i->o] unused internally */
+	unsigned char status;	/* [o] scsi status */
+	unsigned char masked_status;/* [o] shifted, masked scsi status */
+	unsigned char msg_status;/* [o] messaging level data (optional) */
+	unsigned char sb_len_wr; /* [o] byte count actually written to sbp */
+	unsigned short host_status; /* [o] errors from host adapter */
+	unsigned short driver_status;/* [o] errors from software driver */
+	int resid;		/* [o] dxfer_len - actual_transferred */
+	/* unit may be nanoseconds after SG_SET_GET_EXTENDED ioctl use */
+	unsigned int duration;	/* [o] time taken by cmd (unit: millisec) */
+	unsigned int info;	/* [o] auxiliary information */
+} sg_io_hdr_t;
+
+#define SG_INTERFACE_ID_ORIG 'S'
+
+/* Use negative values to flag difference from original sg_header structure */
+#define SG_DXFER_NONE (-1)	/* e.g. a SCSI Test Unit Ready command */
+#define SG_DXFER_TO_DEV (-2)	/* data-out buffer e.g. SCSI WRITE command */
+#define SG_DXFER_FROM_DEV (-3)	/* data-in buffer e.g. SCSI READ command */
+/*
+ * treated like SG_DXFER_FROM_DEV with the additional property than during
+ * indirect IO the user buffer is copied into the kernel buffers _before_
+ * the transfer from the device takes place. Useful if short DMA transfers
+ * (less than requested) are not reported (e.g. resid always 0).
+ */
+#define SG_DXFER_TO_FROM_DEV (-4)
+#define SG_DXFER_UNKNOWN (-5)	/* Unknown data direction, do not use */
+
+/* following flag values can be OR-ed together */
+#define SG_FLAG_DIRECT_IO 1	/* default is indirect IO */
+#define SG_FLAG_UNUSED_LUN_INHIBIT 2	/* default is overwrite lun in SCSI */
+				/* command block (when <= SCSI_2) */
+#define SG_FLAG_MMAP_IO 4	/* request memory mapped IO */
+/* no transfer of kernel buffers to/from user space; to debug indirect IO */
+#define SG_FLAG_NO_DXFER 0x10000
+/* defaults: for sg driver: Q_AT_HEAD; for block layer: Q_AT_TAIL */
+#define SG_FLAG_Q_AT_TAIL 0x10
+#define SG_FLAG_Q_AT_HEAD 0x20
+
+/*
+ * Flags used by ioctl(SG_IOSUBMIT) [abbrev: SG_IOS] and ioctl(SG_IORECEIVE)
+ * [abbrev: SG_IOR] OR-ed into sg_io_v4::flags, also with ioctl(SG_IO) when
+ * sg_io_v4::guard is 'Q' in which case SGV4_FLAG_SYNC is implicitly set.
+ * These flags apply for SG_IOS unless otherwise noted. May be OR-ed together.
+ */
+#define SGV4_FLAG_DIRECT_IO SG_FLAG_DIRECT_IO
+#define SGV4_FLAG_MMAP_IO SG_FLAG_MMAP_IO
+#define SGV4_FLAG_SYNC 0x8	/* similar to ioctl(SG_IO) */
+#define SGV4_FLAG_Q_AT_TAIL SG_FLAG_Q_AT_TAIL
+#define SGV4_FLAG_Q_AT_HEAD SG_FLAG_Q_AT_HEAD
+/* Following 2 flags for request::tag (type: int) manipulations */
+#define SGV4_NO_TAG_REQUIRED 0x100	/* default: SG_IOS yields tag */
+#define SGV4_USE_GIVEN_TAG 0x200	/* SG_IOR selector else ignored */
+#define SGV4_FLAG_IMMED 0x400	/* for polling with SG_IOR else ignored */
+#define SGV4_FLAG_ASYNC 0x800	/* make sync ioctl (e.g. SG_IO) async */
+#define SGV4_FLAG_DEV_SCOPE 0x1000 /* permit SG_IOABORT to have wider scope */
+#define SGV4_FLAG_NO_DXFER SG_FLAG_NO_DXFER
+
+/* following 'info' values are OR-ed together */
+#define SG_INFO_OK_MASK 0x1
+#define SG_INFO_OK 0x0		/* no sense, host nor driver "noise" */
+#define SG_INFO_CHECK 0x1	/* something abnormal happened */
+
+#define SG_INFO_DIRECT_IO_MASK 0x6
+#define SG_INFO_INDIRECT_IO 0x0	/* data xfer via kernel buffers (or no xfer) */
+#define SG_INFO_DIRECT_IO 0x2	/* direct IO requested and performed */
+#define SG_INFO_MIXED_IO 0x4	/* part direct, part indirect IO */
+#define SG_INFO_DEVICE_DETACHING 0x8	/* completed successfully but ... */
+
+
+typedef struct sg_scsi_id {	/* used by SG_GET_SCSI_ID ioctl() */
+	int host_no;	/* as in "scsi<n>" where 'n' is one of 0, 1, 2 etc */
+	int channel;
+	int scsi_id;	/* scsi id of target device */
+	int lun;
+	int scsi_type;	/* TYPE_... defined in scsi/scsi.h */
+	short h_cmd_per_lun;/* host (adapter) maximum commands per lun */
+	short d_queue_depth;/* device (or adapter) maximum queue length */
+	int unused[2];	/* probably find a good use, set 0 for now */
+} sg_scsi_id_t;
+
+typedef struct sg_req_info {	/* used by SG_GET_REQUEST_TABLE ioctl() */
+	char req_state;	/* 0 -> not used, 1 -> written, 2 -> ready to read */
+	char orphan;	/* 0 -> normal request, 1 -> from interruped SG_IO */
+	char sg_io_owned;/* 0 -> complete with read(), 1 -> owned by SG_IO */
+	char problem;	/* 0 -> no problem detected, 1 -> error to report */
+	int pack_id;	/* pack_id associated with request */
+	void __user *usr_ptr;	/* user provided pointer (in new interface) */
+	/*
+	 * millisecs elapsed since the command started (req_state==1) or
+	 * command duration (req_state==2). May be in nanoseconds after
+	 * the SG_SET_GET_EXTENDED ioctl.
+	 */
+	unsigned int duration;
+	int unused;
+} sg_req_info_t;
+
+/*
+ * The following defines may help when using struct sg_extended_info which
+ * is abbreviated to "SEI". A following "M" (i.e. "_SEIM_") indicates a
+ * mask. Most mask values correspond to a integer (usually a __u32) apart
+ * from SG_SEIM_CTL_FLAGS which is for a collection of boolean values
+ * packed into an integer. The mask values for those booleans start with
+ * "SG_CTL_FLAGM_". The scope of these settings, like most other ioctls,
+ * is usually that of the file descriptor the ioctl is executed on. Masks
+ * marked with "rd" are read-only, attempts to write to them are ignored.
+ */
+#define SG_SEIM_RESERVED_SIZE	0x1	/* reserved_sz field valid */
+#define SG_SEIM_RQ_REM_THRESH	0x2	/* rq_rem_sgat_thresh field valid */
+#define SG_SEIM_TOT_FD_THRESH	0x4	/* tot_fd_thresh field valid */
+#define SG_SEIM_CTL_FLAGS	0x8	/* ctl_flags_mask bits in ctl_flags */
+#define SG_SEIM_MINOR_INDEX	0x10	/* sg device minor index number */
+#define SG_SEIM_ALL_BITS	0x1f	/* should be OR of previous items */
+
+#define SG_CTL_FLAGM_TIME_IN_NS	0x1	/* time: nanosecs (def: millisecs) */
+#define SG_CTL_FLAGM_TAG_FOR_PACK_ID	0x2
+#define SG_CTL_FLAGM_OTHER_OPENS	0x4 /* rd: other sg fd_s on this dev */
+#define SG_CTL_FLAGM_ORPHANS	0x8	/* rd: orphaned requests on this fd */
+
+/*
+ * A pointer to the following structure is passed as the third argument to 
+ * ioctl(SG_SET_GET_EXTENDED). Each bit in the *_wr_mask fields causes the
+ * corresponding integer (e.g. reserved_sz) or bit (e.g. the
+ * SG_CTL_FLAG_TIME_IN_NS bit in ctl_flags) to be read from the user space
+ * and modify the driver. Each bit in the *_rd_mask fields causes the
+ * corresponding integer or bit to be fetched from the driver and written
+ * back to the user space. If the same bit is set in both the *_wr_mask and
+ * corresponding *_rd_mask fields, then the write action takes place before
+ * the read action and no other operation will split the two. This structure
+ * is padded to 64 bytes to allow for new values to be added in the future.
+ */
+struct sg_extended_info {
+	__u32	valid_wr_mask;	/* OR-ed SG_SEIM_* values */
+	__u32	valid_rd_mask;	/* OR-ed SG_SEIM_* values */
+	__u32	reserved_sz;	/* data/sgl size of pre-allocated request */
+	__u32	rq_rem_sgat_thresh;/* request re-use: clear data/sgat if > */
+	__u32	tot_fd_thresh;	/* total data/sgat for this fd, 0: no limit */
+	__u32	ctl_flags_wr_mask;	/* OR-ed SG_CTL_FLAGM_* values */
+	__u32	ctl_flags_rd_mask;	/* OR-ed SG_CTL_FLAGM_* values */
+	__u32	ctl_flags;	/* bit values OR-ed, see SG_CTL_FLAGM_* */
+	__u32	minor_index;	/* rd: kernel's sg device minor number */
+	__u8	pad_to_64[28];	/* pad so struct is 64 bytes long */
+};
+
+/*
+ * IOCTLs: Those ioctls that are relevant to the SG 3.x drivers follow.
+ * [Those that only apply to the SG 2.x drivers are at the end of the file.]
+ * (_GET_s yield result via 'int *' 3rd argument unless otherwise indicated)
+ */
+
+#define SG_EMULATED_HOST 0x2203	/* true for emulated host adapter (ATAPI) */
+
+/*
+ * Used to configure SCSI command transformation layer for ATAPI devices.
+ * Only supported by the ide-scsi driver. 20181014 No longer supported, this
+ * driver passes them to the mid-level which returns a EINVAL (22) errno.
+ *
+ * Original note: N.B. 3rd arg is not pointer but value: 3rd arg = 0 to
+ * disable transform, 1 to enable it
+ */
+#define SG_SET_TRANSFORM 0x2204
+#define SG_GET_TRANSFORM 0x2205
+
+#define SG_SET_RESERVED_SIZE 0x2275  /* request new reserved buffer size */
+#define SG_GET_RESERVED_SIZE 0x2272  /* actual size of reserved buffer */
+
+/*
+ * SCSI_GENERIC_MAJOR has the value 0x15 so the author has no idea why
+ * this driver has used 0x22 as its upper byte (when viewed as a __u16).
+ * As the driver is 26 years old, SCSI_GENERIC_MAJOR may have been 0x22
+ * at some point in the distant past.
+ */
+#define SG_SET_GET_EXTENDED _IOWR(SCSI_GENERIC_MAJOR, 0x51,	\
+				  struct sg_extended_info)
+
+/* The following ioctl has a 'sg_scsi_id_t *' object as its 3rd argument. */
+#define SG_GET_SCSI_ID 0x2276   /* Yields fd's bus, chan, dev, lun + type */
+/* SCSI id information can also be obtained from SCSI_IOCTL_GET_IDLUN */
+
+/* Override host setting and always DMA using low memory ( <16MB on i386) */
+#define SG_SET_FORCE_LOW_DMA 0x2279  /* 0-> use adapter setting, 1-> force */
+#define SG_GET_LOW_DMA 0x227a	/* 0-> use all ram for dma; 1-> low dma ram */
+
+/*
+ * When SG_SET_FORCE_PACK_ID set to 1, pack_id is input to read() which
+ * tries to fetch a packet with a matching pack_id, waits, or returns EAGAIN.
+ * If pack_id is -1 then read oldest waiting. When ...FORCE_PACK_ID set to 0
+ * then pack_id ignored by read() and oldest readable fetched.
+ */
+#define SG_SET_FORCE_PACK_ID 0x227b
+#define SG_GET_PACK_ID 0x227c	/* Yields oldest readable pack_id (or -1) */
+
+#define SG_GET_NUM_WAITING 0x227d /* Number of commands awaiting read() */
+
+/* Yields max scatter gather tablesize allowed by current host adapter */
+#define SG_GET_SG_TABLESIZE 0x227F  /* 0 implies can't do scatter gather */
+
+#define SG_GET_VERSION_NUM 0x2282 /* Example: version 2.1.34 yields 20134 */
+
+/* Returns -EBUSY if occupied. 3rd argument pointer to int (see next) */
+#define SG_SCSI_RESET 0x2284
+/*
+ * Associated values that can be given to SG_SCSI_RESET follow.
+ * SG_SCSI_RESET_NO_ESCALATE may be OR-ed to the _DEVICE, _TARGET, _BUS
+ * or _HOST reset value so only that action is attempted.
+ */
+#define		SG_SCSI_RESET_NOTHING	0
+#define		SG_SCSI_RESET_DEVICE	1
+#define		SG_SCSI_RESET_BUS	2
+#define		SG_SCSI_RESET_HOST	3
+#define		SG_SCSI_RESET_TARGET	4
+#define		SG_SCSI_RESET_NO_ESCALATE	0x100
+
+/* synchronous SCSI command ioctl, (only in version 3 interface) */
+#define SG_IO 0x2285	/* similar effect as write() followed by read() */
+
+#define SG_GET_REQUEST_TABLE 0x2286	/* yields table of active requests */
+
+/* How to treat EINTR during SG_IO ioctl(), only in SG 3.x series */
+#define SG_SET_KEEP_ORPHAN 0x2287 /* 1 -> hold for read(), 0 -> drop (def) */
+#define SG_GET_KEEP_ORPHAN 0x2288
+
+/*
+ * Yields scsi midlevel's access_count for this SCSI device. 20181014 No
+ * longer available, always yields 1.
+ */
+#define SG_GET_ACCESS_COUNT 0x2289
+
+
+/*
+ * Largest size (in bytes) a single scatter-gather list element can have.
+ * The value used by the driver is 'max(SG_SCATTER_SZ, PAGE_SIZE)'.
+ * This value should be a power of 2 (and may be rounded up internally).
+ * If scatter-gather is not supported by adapter then this value is the
+ * largest data block that can be read/written by a single scsi command.
+ */
+#define SG_SCATTER_SZ (8 * 4096)
+
+#define SG_DEFAULT_RETRIES 0
+
+/* Defaults, commented if they differ from original sg driver */
+#define SG_DEF_FORCE_PACK_ID 0
+#define SG_DEF_KEEP_ORPHAN 0
+#define SG_DEF_RESERVED_SIZE SG_SCATTER_SZ /* load time option */
+
+/*
+ * Maximum outstanding requests (i.e write()s without corresponding read()s)
+ * yields EDOM from write() if exceeded. This limit only applies prior to
+ * version 3.9 . It is still used as a maximum number of sg_req_info objects
+ * that are returned from the SG_GET_REQUEST_TABLE ioctl.
+ */
+#define SG_MAX_QUEUE 16
+
+#define SG_BIG_BUFF SG_DEF_RESERVED_SIZE    /* for backward compatibility */
+
+/*
+ * Alternate style type names, "..._t" variants (as found in the
+ * 'typedef struct * {};' definitions above) are preferred to these:
+ */
+typedef struct sg_io_hdr Sg_io_hdr;
+typedef struct sg_io_vec Sg_io_vec;
+typedef struct sg_scsi_id Sg_scsi_id;
+typedef struct sg_req_info Sg_req_info;
+
+
+/* vvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvv */
+/*   The older SG interface based on the 'sg_header' structure follows.   */
+/* ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ */
+
+#define SG_MAX_SENSE 16	/* this only applies to the sg_header interface */
+
+struct sg_header {
+	int pack_len;	/* [o] reply_len (ie useless), ignored as input */
+	int reply_len;	/* [i] max length of expected reply (inc. sg_header) */
+	int pack_id;	/* [io] id number of packet (use ints >= 0) */
+	int result;	/* [o] 0==ok, else (+ve) Unix errno (best ignored) */
+	unsigned int twelve_byte:1;
+	    /* [i] Force 12 byte command length for group 6 & 7 commands  */
+	unsigned int target_status:5;	/* [o] scsi status from target */
+	unsigned int host_status:8;	/* [o] host status (see "DID" codes) */
+	unsigned int driver_status:8;	/* [o] driver status+suggestion */
+	unsigned int other_flags:10;	/* unused */
+	unsigned char sense_buffer[SG_MAX_SENSE];
+	/*
+	 * [o] Output in 3 cases:
+	 *	when target_status is CHECK_CONDITION or
+	 *	when target_status is COMMAND_TERMINATED or
+	 *	when (driver_status & DRIVER_SENSE) is true.
+	 */
+};
+
+/*
+ * IOCTLs: The following are not required (or ignored) when the sg_io_hdr_t
+ *  interface is used. They are kept for backward compatibility with
+ * the original and version 2 drivers.
+ */
+
+#define SG_SET_TIMEOUT 0x2201  /* unit: jiffies (10ms on i386) */
+#define SG_GET_TIMEOUT 0x2202  /* yield timeout as _return_ value */
+
+/*
+ * Get/set command queuing state per fd (default is SG_DEF_COMMAND_Q.
+ * Each time a sg_io_hdr_t object is seen on this file descriptor, this
+ * command queuing flag is set on (overriding the previous setting).
+ */
+#define SG_GET_COMMAND_Q 0x2270   /* Yields 0 (queuing off) or 1 (on) */
+#define SG_SET_COMMAND_Q 0x2271   /* Change queuing state with 0 or 1 */
+
+/*
+ * Turn on/off error sense trace (1 and 0 respectively, default is off).
+ * Try using: "# cat /proc/scsi/sg/debug" instead in the v3 driver
+ */
+#define SG_SET_DEBUG 0x227e    /* 0 -> turn off debug */
+
+/*
+ * override SCSI command length with given number on the next write() on
+ * this file descriptor
+ */
+#define SG_NEXT_CMD_LEN 0x2283
+
+/*
+ * New ioctls to replace async write()/read() interface. Present in version
+ * 4 and later of the sg driver [>20181014]. These two ioctls accept both
+ * the sg_v3 interface (structure defined above) and the sg_v4 interface
+ * (structure defined in <include/uapi/linux/bsg.h> ). Following "read" and
+ * "write" terms are from the driver's POV, the _IO macros from users' POV.
+ */
+/* via pointer reads sg v3 or v4 object, optionally writes tag, so _IOWR */
+#define SG_IOSUBMIT _IOWR(SCSI_GENERIC_MAJOR, 0x41, struct sg_io_v4)
+/* via pointer optionally reads tag, writes sg v3 or v4 object, so _IOWR */
+#define SG_IORECEIVE _IOWR(SCSI_GENERIC_MAJOR, 0x42, struct sg_io_v4)
+/* via pointer reads v4 object (including tag), writes nothing, so _IOW */
+#define SG_IOABORT _IOW(SCSI_GENERIC_MAJOR, 0x43, struct sg_io_v4)
+
+/* command queuing is always on when the new interface is used */
+#define SG_DEF_COMMAND_Q 0
+
+#define SG_DEF_UNDERRUN_FLAG 0
+
+#define SG_DEFAULT_TIMEOUT	(60*HZ)	/* HZ == 'jiffies in 1 second' */
+
+#endif
