Release 4.14 include/scsi/sg.h
/* SPDX-License-Identifier: GPL-2.0 */
#ifndef _SCSI_GENERIC_H
#define _SCSI_GENERIC_H
#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
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' */
#endif
#define SG_DEF_COMMAND_Q 0
/* command queuing is always on when
the new interface is used */
#define SG_DEF_UNDERRUN_FLAG 0
#endif
Overall Contributors
| Person | Tokens | Prop | Commits | CommitProp |
| Linus Torvalds (pre-git) | 580 | 88.28% | 12 | 42.86% |
| Linus Torvalds | 21 | 3.20% | 2 | 7.14% |
| Douglas Gilbert | 18 | 2.74% | 6 | 21.43% |
| Rolf Fokkens | 12 | 1.83% | 1 | 3.57% |
| Dave Young | 10 | 1.52% | 1 | 3.57% |
| Al Viro | 7 | 1.07% | 2 | 7.14% |
| Brian King | 4 | 0.61% | 1 | 3.57% |
| Jens Axboe | 3 | 0.46% | 1 | 3.57% |
| Greg Kroah-Hartman | 1 | 0.15% | 1 | 3.57% |
| Patrick Mansfield | 1 | 0.15% | 1 | 3.57% |
| Total | 657 | 100.00% | 28 | 100.00% |
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