/* Copyright (C) 1997-2024 Free Software Foundation, Inc.
This file is part of the GNU C Library.
The GNU C Library is free software; you can redistribute it and/or
modify it under the terms of the GNU Lesser General Public
License as published by the Free Software Foundation; either
version 2.1 of the License, or (at your option) any later version.
The GNU C Library is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
Lesser General Public License for more details.
You should have received a copy of the GNU Lesser General Public
License along with the GNU C Library; if not, see
<https://www.gnu.org/licenses/>. */
/*
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
*/
#ifndef _SCSI_SG_H
#define _SCSI_SG_H 1
#include <features.h>
#define __need_size_t
#include <stddef.h>
/* New interface introduced in the 3.x SG drivers follows */
/* Same structure as used by readv() Linux system call. It defines one
scatter-gather element. */
typedef struct sg_iovec
{
void * 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 ( <= 16 bytes) */
unsigned char mx_sb_len; /* [i] max length to write to sbp */
unsigned short int iovec_count; /* [i] 0 implies no scatter gather */
unsigned int dxfer_len; /* [i] byte count of data transfer */
void * dxferp; /* [i], [*io] points to data transfer memory
or scatter gather list */
unsigned char * cmdp; /* [i], [*i] points to command to perform */
unsigned char * 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 * 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 int host_status; /* [o] errors from host adapter */
unsigned short int 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;
/* 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 */
/* following flag values can be "or"-ed together */
#define SG_FLAG_DIRECT_IO 1 /* default is indirect IO */
#define SG_FLAG_LUN_INHIBIT 2 /* default is to put device's lun into */
/* the 2nd byte of SCSI command */
#define SG_FLAG_NO_DXFER 0x10000 /* no transfer of kernel buffers to/from */
/* user space (debug indirect IO) */
/* The 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 */
/* Request information about a specific SG device, used by
SG_GET_SCSI_ID ioctl (). */
struct sg_scsi_id {
/* Host number as in "scsi<n>" where 'n' is one of 0, 1, 2 etc. */
int host_no;
int channel;
/* SCSI id of target device. */
int scsi_id;
int lun;
/* TYPE_... defined in <scsi/scsi.h>. */
int scsi_type;
/* Host (adapter) maximum commands per lun. */
short int h_cmd_per_lun;
/* Device (or adapter) maximum queue length. */
short int d_queue_depth;
/* Unused, set to 0 for now. */
int unused[2];
};
/* Used by SG_GET_REQUEST_TABLE ioctl(). */
typedef struct sg_req_info {
char req_state; /* 0 -> not used, 1 -> written, 2 -> ready to read */
char orphan; /* 0 -> normal request, 1 -> from interrupted 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 * 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;
/* 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 */
#define SG_SCSI_RESET_NOTHING 0
#define SG_SCSI_RESET_DEVICE 1
#define SG_SCSI_RESET_BUS 2
#define SG_SCSI_RESET_HOST 3
/* 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
#define SG_SCATTER_SZ (8 * 4096) /* PAGE_SIZE not available to user */
/* Largest size (in bytes) a single scatter-gather list element can have.
The value must be a power of 2 and <= (PAGE_SIZE * 32) [131072 bytes on
i386]. The minimum value is PAGE_SIZE. If scatter-gather not supported
by adapter then this value is the largest data block that can be
read/written by a single scsi command. The user can find the value of
PAGE_SIZE by calling getpagesize() defined in unistd.h . */
#define SG_DEFAULT_RETRIES 1
/* Defaults, commented if they differ from original sg driver */
#define SG_DEF_FORCE_LOW_DMA 0 /* was 1 -> memory below 16MB on i386 */
#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
{
/* Length of incoming packet (including header). */
int pack_len;
/* Maximal length of expected reply. */
int reply_len;
/* Id number of packet. */
int pack_id;
/* 0==ok, otherwise error number. */
int result;
/* Force 12 byte command length for group 6 & 7 commands. */
unsigned int twelve_byte:1;
/* SCSI status from target. */
unsigned int target_status:5;
/* Host status (see "DID" codes). */
unsigned int host_status:8;
/* Driver status+suggestion. */
unsigned int driver_status:8;
/* Unused. */
unsigned int other_flags:10;
/* 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. */
unsigned char sense_buffer[SG_MAX_SENSE];
};
/* 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 /* Set timeout; *(int *)arg==timeout. */
#define SG_GET_TIMEOUT 0x2202 /* Get timeout; return timeout. */
/* Get/set command queuing state per fd (default is SG_DEF_COMMAND_Q). */
#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 error sense trace (1..8), dump this device to log/console (9)
or dump all sg device states ( >9 ) to log/console. */
#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 */
#define SG_DEFAULT_TIMEOUT (60*HZ) /* HZ == 'jiffies in 1 second' */
#define SG_DEF_COMMAND_Q 0 /* command queuing is always on when
the new interface is used */
#define SG_DEF_UNDERRUN_FLAG 0
#endif /* scsi/sg.h */
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