linux-imx

// SPDX-License-Identifier: GPL-2.0-or-later

/*

 *  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.c):

 *        Copyright (C) 1992 Lawrence Foard

 * Version 2 and 3 extensions to driver:

 *        Copyright (C) 1998 - 2014 Douglas Gilbert

 */

​

static int sg_version_num = 30536;  /* 2 digits for each component */

#define SG_VERSION_STR "3.5.36"

​

/*

 *  D. P. Gilbert (dgilbert@interlog.com), notes:

 *      - scsi logging is available via SCSI_LOG_TIMEOUT macros. First

 *        the kernel/module needs to be built with CONFIG_SCSI_LOGGING

 *        (otherwise the macros compile to empty statements).

 *

 */

#include <linux/module.h>

​

#include <linux/fs.h>

#include <linux/kernel.h>

#include <linux/sched.h>

#include <linux/string.h>

#include <linux/mm.h>

#include <linux/errno.h>

#include <linux/mtio.h>

#include <linux/ioctl.h>

#include <linux/slab.h>

#include <linux/fcntl.h>

#include <linux/init.h>

#include <linux/poll.h>

#include <linux/moduleparam.h>

#include <linux/cdev.h>

#include <linux/idr.h>

#include <linux/seq_file.h>

#include <linux/blkdev.h>

#include <linux/delay.h>

#include <linux/blktrace_api.h>

#include <linux/mutex.h>

#include <linux/atomic.h>

#include <linux/ratelimit.h>

#include <linux/uio.h>

#include <linux/cred.h> /* for sg_check_file_access() */

​

#include "scsi.h"

#include <scsi/scsi_dbg.h>

#include <scsi/scsi_host.h>

#include <scsi/scsi_driver.h>

#include <scsi/scsi_ioctl.h>

#include <scsi/sg.h>

​

#include "scsi_logging.h"

​

#ifdef CONFIG_SCSI_PROC_FS

#include <linux/proc_fs.h>

static char *sg_version_date = "20140603";

​

static int sg_proc_init(void);

#endif

​

#define SG_ALLOW_DIO_DEF 0

​

#define SG_MAX_DEVS 32768

​

/* SG_MAX_CDB_SIZE should be 260 (spc4r37 section 3.1.30) however the type

 * of sg_io_hdr::cmd_len can only represent 255. All SCSI commands greater

 * than 16 bytes are "variable length" whose length is a multiple of 4

 */

#define SG_MAX_CDB_SIZE 252

​

#define SG_DEFAULT_TIMEOUT mult_frac(SG_DEFAULT_TIMEOUT_USER, HZ, USER_HZ)

​

int sg_big_buff = SG_DEF_RESERVED_SIZE;

/* N.B. This variable is readable and writeable via

   /proc/scsi/sg/def_reserved_size . Each time sg_open() is called a buffer

   of this size (or less if there is not enough memory) will be reserved

   for use by this file descriptor. [Deprecated usage: this variable is also

   readable via /proc/sys/kernel/sg-big-buff if the sg driver is built into

   the kernel (i.e. it is not a module).] */

static int def_reserved_size = -1;  /* picks up init parameter */

static int sg_allow_dio = SG_ALLOW_DIO_DEF;

​

static int scatter_elem_sz = SG_SCATTER_SZ;

static int scatter_elem_sz_prev = SG_SCATTER_SZ;

​

#define SG_SECTOR_SZ 512