[07/18] sg: move header to uapi section
diff mbox series

Message ID 20190617033934.5051-8-dgilbert@interlog.com
State Superseded
Headers show
Series
  • sg: add v4 interface
Related show

Commit Message

Douglas Gilbert June 17, 2019, 3:39 a.m. UTC
Move user interface part of scsi/sg.h into the new header file:
include/uapi/scsi/sg.h . Since scsi/sg.h includes the new header,
other code including scsi/sg.h should not be impacted.

Signed-off-by: Douglas Gilbert <dgilbert@interlog.com>
---
 include/scsi/sg.h      | 268 ++-------------------------------
 include/uapi/scsi/sg.h | 329 +++++++++++++++++++++++++++++++++++++++++
 2 files changed, 338 insertions(+), 259 deletions(-)
 create mode 100644 include/uapi/scsi/sg.h

Patch
diff mbox series

diff --git a/include/scsi/sg.h b/include/scsi/sg.h
index f91bcca604e4..46fc7cbffd78 100644
--- a/include/scsi/sg.h
+++ b/include/scsi/sg.h
@@ -4,271 +4,21 @@ 
 
 #include <linux/compiler.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 - 2014 Douglas Gilbert
- *
- *  Version: 3.5.36 (20140603)
- *  This version is for 2.6 and 3 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
- */
-
 #ifdef __KERNEL__
 extern int sg_big_buff; /* for sysctl */
 #endif
 
+/*
+ * In version 3.9.01 of the sg driver, this file was spilt in two, with the
+ * bulk of the user space interface being placed in the file being included
+ * in the following line.
+ */
+#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	/* because of conflicting 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..bb1be50d7b01
--- /dev/null
+++ b/include/uapi/scsi/sg.h
@@ -0,0 +1,329 @@ 
+/* SPDX-License-Identifier: GPL-2.0 */
+#ifndef _UAPI_SCSI_SG_H
+#define _UAPI_SCSI_SG_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
+ *
+ * Later extensions (versions 2, 3 and 4) to driver:
+ *   Copyright (C) 1998 - 2018 Douglas Gilbert
+ *
+ * Version 4.0.11 (20190502)
+ *  This version is for Linux 4 and 5 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
+ */
+
+#include <linux/types.h>
+#include <linux/major.h>
+
+/* bsg.h contains the sg v4 user space interface structure (sg_io_v4). */
+#include <linux/bsg.h>
+
+/*
+ * Same structure as used by readv() call. It defines one scatter-gather
+ * element. "Scatter-gather" is abbreviated to "sgat" in this 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 sgat list */
+	unsigned int dxfer_len;	/* [i] byte count of data transfer */
+	/* dxferp 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 */
+/*
+ * SG_DXFER_TO_FROM_DEV is 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 in v3::flags or v4::flags */
+#define SG_FLAG_DIRECT_IO 1	/* default is indirect IO */
+/* SG_FLAG_UNUSED_LUN_INHIBIT is ignored in sg v4 driver */
+#define SG_FLAG_UNUSED_LUN_INHIBIT 2  /* ignored, was LUN overwrite in cdb */
+#define SG_FLAG_MMAP_IO 4	/* request memory mapped IO */
+/* no transfer of kernel buffers to/from user space; used for sharing */
+#define SG_FLAG_NO_DXFER 0x10000
+/* defaults: for sg driver (v3_v4): Q_AT_HEAD; for block layer: Q_AT_TAIL */
+#define SG_FLAG_Q_AT_TAIL 0x10
+#define SG_FLAG_Q_AT_HEAD 0x20
+
+/* Output (potentially OR-ed together) in v3::info or v4::info field */
+#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	/* not used, always 0 */
+#define SG_INFO_DEVICE_DETACHING 0x8	/* completed successfully but ... */
+#define SG_INFO_ABORTED 0x10	/* this command has been aborted */
+#define SG_INFO_MRQ_FINI 0x20	/* marks multi-reqs that have finished */
+
+/*
+ * Pointer to object of this structure filled by ioctl(SG_GET_SCSI_ID). Last
+ * field changed in v4 driver, was 'int unused[2]' so remains the same size.
+ */
+typedef struct sg_scsi_id {
+	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;	/* lower 32 bits of internal 64 bit integer */
+	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];
+} sg_scsi_id_t;
+
+/* For backward compatibility v4 driver yields at most SG_MAX_QUEUE of these */
+typedef struct sg_req_info {	/* used by SG_GET_REQUEST_TABLE ioctl() */
+	char req_state;	/* See 'enum sg_rq_state' definition in v4 driver */
+	char orphan;	/* 0 -> normal request, 1 -> from interrupted SG_IO */
+	/* sg_io_owned set imples synchronous, clear implies asynchronous */
+	char sg_io_owned;/* 0 -> complete with read(), 1 -> owned by SG_IO */
+	char problem;	/* 0 -> no problem detected, 1 -> error to report */
+	/* If SG_CTL_FLAGM_TAG_FOR_PACK_ID set on fd then next field is tag */
+	int pack_id;	/* pack_id, in v4 driver may be tag instead */
+	void __user *usr_ptr;	/* user provided pointer in v3+v4 interface */
+	unsigned int duration;
+	int unused;
+} sg_req_info_t;
+
+/*
+ * 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 */
+
+/* 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 (or tag) is input to read() or
+ * ioctl(SG_IO_RECEIVE). These functions wait until matching packet (request/
+ * command) is finished but they will return with EAGAIN quickly if the file
+ * descriptor was opened O_NONBLOCK or (in v4) if SGV4_FLAG_IMMED is given.
+ * The tag is used when SG_CTL_FLAGM_TAG_FOR_PACK_ID is set on the parent
+ * file descriptor (default: use pack_id). If pack_id or tag is -1 then read
+ * oldest waiting and this is the same action as when FORCE_PACK_ID is
+ * clear on the parent file descriptor. In the v4 interface the pack_id is
+ * placed the in sg_io_v4::request_extra field .
+ */
+#define SG_SET_FORCE_PACK_ID 0x227b	/* pack_id or in v4 can be tag */
+#define SG_GET_PACK_ID 0x227c  /* Yields oldest readable pack_id/tag, 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 */
+
+/*
+ * Integer form of version number: [x]xyyzz where [x] empty when x=0 .
+ * String form of version number: "[x]x.[y]y.zz"
+ */
+#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, (for version 3 and 4 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 v3 and v4 driver */
+#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
+
+
+/*
+ * Default 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). In the
+ * v4 driver this can be changed by ioctl(SG_SET_GET_EXTENDED{SGAT_ELEM_SZ}).
+ */
+#define SG_SCATTER_SZ (8 * 4096)
+
+/* sg driver users' code should handle retries (e.g. from Unit Attentions) */
+#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 v1+v2 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 v3 or v4
+ * interface is used as those structures contain a timeout field. These
+ * ioctls are kept for backward compatibility with v1+v2 interfaces.
+ */
+
+#define SG_SET_TIMEOUT 0x2201  /* unit: (user space) jiffies */
+#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).
+ * This setting defaults to 0 (i.e. no queuing) but gets set the first
+ * time that fd sees a v3 or v4 interface request.
+ */
+#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 (v1 and v2 interface only)
+ */
+#define SG_NEXT_CMD_LEN 0x2283
+
+/* command queuing is always on when the v3 or v4 interface is used */
+#define SG_DEF_COMMAND_Q 0
+
+#define SG_DEF_UNDERRUN_FLAG 0
+
+/* If the timeout value in the v3_v4 interfaces is 0, this value is used */
+#define SG_DEFAULT_TIMEOUT	(60*HZ)	/* HZ == 'jiffies in 1 second' */
+
+#endif		/* end of _UAPI_SCSI_SG_H guard */