blob: 4042fed385270bd7d494394c41a1b2de04ae1602 [file] [log] [blame]
/*
* 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 - 2002 Douglas Gilbert
*
* Modified 19-JAN-1998 Richard Gooch <rgooch@atnf.csiro.au> Devfs support
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2, or (at your option)
* any later version.
*
*/
#include <linux/config.h>
static char *sg_version_str = "3.5.28 [20030308]";
static int sg_version_num = 30528; /* 2 digits for each component */
/*
* D. P. Gilbert (dgilbert@interlog.com, dougg@triode.net.au), 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).
* Then before running the program to be debugged enter:
* # echo "scsi log timeout 7" > /proc/scsi/scsi
* This will send copious output to the console and the log which
* is usually /var/log/messages. To turn off debugging enter:
* # echo "scsi log timeout 0" > /proc/scsi/scsi
* The 'timeout' token was chosen because it is relatively unused.
* The token 'hlcomplete' should be used but that triggers too
* much output from the sd device driver. To dump the current
* state of the SCSI mid level data structures enter:
* # echo "scsi dump 1" > /proc/scsi/scsi
* To dump the state of sg's data structures use:
* # cat /proc/scsi/sg/debug
*
*/
#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/fcntl.h>
#include <linux/init.h>
#include <linux/poll.h>
#include <linux/vmalloc.h>
#include <linux/smp_lock.h>
#include <linux/moduleparam.h>
#include <asm/io.h>
#include <asm/uaccess.h>
#include <asm/system.h>
#include <linux/blk.h>
#include "scsi.h"
#include "hosts.h"
#include <scsi/scsi_ioctl.h>
#include <scsi/sg.h>
#ifdef CONFIG_PROC_FS
#include <linux/proc_fs.h>
static int sg_proc_init(void);
static void sg_proc_cleanup(void);
#endif
#ifndef LINUX_VERSION_CODE
#include <linux/version.h>
#endif /* LINUX_VERSION_CODE */
#define SG_ALLOW_DIO_DEF 0
#define SG_ALLOW_DIO_CODE /* compile out by commenting this define */
#define SG_MAX_DEVS_MASK ((1U << KDEV_MINOR_BITS) - 1)
/*
* Suppose you want to calculate the formula muldiv(x,m,d)=int(x * m / d)
* Then when using 32 bit integers x * m may overflow during the calculation.
* Replacing muldiv(x) by muldiv(x)=((x % d) * m) / d + int(x / d) * m
* calculates the same, but prevents the overflow when both m and d
* are "small" numbers (like HZ and USER_HZ).
* Of course an overflow is inavoidable if the result of muldiv doesn't fit
* in 32 bits.
*/
#define MULDIV(X,MUL,DIV) ((((X % DIV) * MUL) / DIV) + ((X / DIV) * MUL))
#define SG_DEFAULT_TIMEOUT MULDIV(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;
#define SG_SECTOR_SZ 512
#define SG_SECTOR_MSK (SG_SECTOR_SZ - 1)
#define SG_DEV_ARR_LUMP 6 /* amount to over allocate sg_dev_arr by */
static int sg_attach(Scsi_Device *);
static void sg_detach(Scsi_Device *);
static Scsi_Request *dummy_cmdp; /* only used for sizeof */
static rwlock_t sg_dev_arr_lock = RW_LOCK_UNLOCKED; /* Also used to lock
file descriptor list for device */
static struct Scsi_Device_Template sg_template = {
.module = THIS_MODULE,
.list = LIST_HEAD_INIT(sg_template.list),
.name = "generic",
.scsi_type = 0xff,
.attach = sg_attach,
.detach = sg_detach,
.scsi_driverfs_driver = {
.name = "sg",
},
};
typedef struct sg_scatter_hold { /* holding area for scsi scatter gather info */
unsigned short k_use_sg; /* Count of kernel scatter-gather pieces */
unsigned short sglist_len; /* size of malloc'd scatter-gather list ++ */
unsigned bufflen; /* Size of (aggregate) data buffer */
unsigned b_malloc_len; /* actual len malloc'ed in buffer */
void *buffer; /* Data buffer or scatter list (k_use_sg>0) */
char dio_in_use; /* 0->indirect IO (or mmap), 1->dio */
unsigned char cmd_opcode; /* first byte of command */
} Sg_scatter_hold;
struct sg_device; /* forward declarations */
struct sg_fd;
typedef struct sg_request { /* SG_MAX_QUEUE requests outstanding per file */
Scsi_Request *my_cmdp; /* != 0 when request with lower levels */
struct sg_request *nextrp; /* NULL -> tail request (slist) */
struct sg_fd *parentfp; /* NULL -> not in use */
Sg_scatter_hold data; /* hold buffer, perhaps scatter list */
sg_io_hdr_t header; /* scsi command+info, see <scsi/sg.h> */
unsigned char sense_b[sizeof (dummy_cmdp->sr_sense_buffer)];
char res_used; /* 1 -> using reserve buffer, 0 -> not ... */
char orphan; /* 1 -> drop on sight, 0 -> normal */
char sg_io_owned; /* 1 -> packet belongs to SG_IO */
volatile char done; /* 0->before bh, 1->before read, 2->read */
} Sg_request;
typedef struct sg_fd { /* holds the state of a file descriptor */
struct sg_fd *nextfp; /* NULL when last opened fd on this device */
struct sg_device *parentdp; /* owning device */
wait_queue_head_t read_wait; /* queue read until command done */
rwlock_t rq_list_lock; /* protect access to list in req_arr */
int timeout; /* defaults to SG_DEFAULT_TIMEOUT */
int timeout_user; /* defaults to SG_DEFAULT_TIMEOUT_USER */
Sg_scatter_hold reserve; /* buffer held for this file descriptor */
unsigned save_scat_len; /* original length of trunc. scat. element */
Sg_request *headrp; /* head of request slist, NULL->empty */
struct fasync_struct *async_qp; /* used by asynchronous notification */
Sg_request req_arr[SG_MAX_QUEUE]; /* used as singly-linked list */
char low_dma; /* as in parent but possibly overridden to 1 */
char force_packid; /* 1 -> pack_id input to read(), 0 -> ignored */
volatile char closed; /* 1 -> fd closed but request(s) outstanding */
char cmd_q; /* 1 -> allow command queuing, 0 -> don't */
char next_cmd_len; /* 0 -> automatic (def), >0 -> use on next write() */
char keep_orphan; /* 0 -> drop orphan (def), 1 -> keep for read() */
char mmap_called; /* 0 -> mmap() never called on this fd */
} Sg_fd;
typedef struct sg_device { /* holds the state of each scsi generic device */
struct Scsi_Device_Template *driver;
Scsi_Device *device;
wait_queue_head_t o_excl_wait; /* queue open() when O_EXCL in use */
int sg_tablesize; /* adapter's max scatter-gather table size */
Sg_fd *headfp; /* first open fd belonging to this device */
volatile char detached; /* 0->attached, 1->detached pending removal */
volatile char exclude; /* opened for exclusive access */
char sgdebug; /* 0->off, 1->sense, 9->dump dev, 10-> all devs */
struct device sg_driverfs_dev;
struct gendisk *disk;
} Sg_device;
static int sg_fasync(int fd, struct file *filp, int mode);
static void sg_cmd_done(Scsi_Cmnd * SCpnt); /* tasklet or soft irq callback */
static int sg_start_req(Sg_request * srp);
static void sg_finish_rem_req(Sg_request * srp);
static int sg_build_indirect(Sg_scatter_hold * schp, Sg_fd * sfp, int buff_size);
static int sg_build_sgat(Sg_scatter_hold * schp, const Sg_fd * sfp,
int tablesize);
static ssize_t sg_new_read(Sg_fd * sfp, char *buf, size_t count,
Sg_request * srp);
static ssize_t sg_new_write(Sg_fd * sfp, const char *buf, size_t count,
int blocking, int read_only, Sg_request ** o_srp);
static int sg_common_write(Sg_fd * sfp, Sg_request * srp,
unsigned char *cmnd, int timeout, int blocking);
static int sg_u_iovec(sg_io_hdr_t * hp, int sg_num, int ind,
int wr_xf, int *countp, unsigned char **up);
static int sg_write_xfer(Sg_request * srp);
static int sg_read_xfer(Sg_request * srp);
static int sg_read_oxfer(Sg_request * srp, char *outp, int num_read_xfer);
static void sg_remove_scat(Sg_scatter_hold * schp);
static void sg_build_reserve(Sg_fd * sfp, int req_size);
static void sg_link_reserve(Sg_fd * sfp, Sg_request * srp, int size);
static void sg_unlink_reserve(Sg_fd * sfp, Sg_request * srp);
static char *sg_page_malloc(int rqSz, int lowDma, int *retSzp);
static void sg_page_free(char *buff, int size);
static Sg_fd *sg_add_sfp(Sg_device * sdp, int dev);
static int sg_remove_sfp(Sg_device * sdp, Sg_fd * sfp);
static void __sg_remove_sfp(Sg_device * sdp, Sg_fd * sfp);
static Sg_request *sg_get_rq_mark(Sg_fd * sfp, int pack_id);
static Sg_request *sg_add_request(Sg_fd * sfp);
static int sg_remove_request(Sg_fd * sfp, Sg_request * srp);
static int sg_res_in_use(Sg_fd * sfp);
static int sg_ms_to_jif(unsigned int msecs);
static inline unsigned sg_jif_to_ms(int jifs);
static int sg_allow_access(unsigned char opcode, char dev_type);
static int sg_build_direct(Sg_request * srp, Sg_fd * sfp, int dxfer_len);
// static void sg_unmap_and(Sg_scatter_hold * schp, int free_also);
static Sg_device *sg_get_dev(int dev);
static inline unsigned char *sg_scatg2virt(const struct scatterlist *sclp);
#ifdef CONFIG_PROC_FS
static int sg_last_dev(void);
#endif
static Sg_device **sg_dev_arr = NULL;
static int sg_dev_max;
static int sg_nr_dev;
#define SZ_SG_HEADER sizeof(struct sg_header)
#define SZ_SG_IO_HDR sizeof(sg_io_hdr_t)
#define SZ_SG_IOVEC sizeof(sg_iovec_t)
#define SZ_SG_REQ_INFO sizeof(sg_req_info_t)
static int
sg_open(struct inode *inode, struct file *filp)
{
int dev = minor(inode->i_rdev);
int flags = filp->f_flags;
Sg_device *sdp;
Sg_fd *sfp;
int res;
int retval = -EBUSY;
SCSI_LOG_TIMEOUT(3, printk("sg_open: dev=%d, flags=0x%x\n", dev, flags));
sdp = sg_get_dev(dev);
if ((!sdp) || (!sdp->device))
return -ENXIO;
if (sdp->detached)
return -ENODEV;
/* This driver's module count bumped by fops_get in <linux/fs.h> */
/* Prevent the device driver from vanishing while we sleep */
retval = scsi_device_get(sdp->device);
if (retval)
return retval;
if (!((flags & O_NONBLOCK) ||
scsi_block_when_processing_errors(sdp->device))) {
retval = -ENXIO;
/* we are in error recovery for this device */
goto error_out;
}
if (flags & O_EXCL) {
if (O_RDONLY == (flags & O_ACCMODE)) {
retval = -EPERM; /* Can't lock it with read only access */
goto error_out;
}
if (sdp->headfp && (flags & O_NONBLOCK))
goto error_out;
res = 0;
__wait_event_interruptible(sdp->o_excl_wait,
((sdp->headfp || sdp->exclude) ? 0 : (sdp->exclude = 1)), res);
if (res) {
retval = res; /* -ERESTARTSYS because signal hit process */
goto error_out;
}
} else if (sdp->exclude) { /* some other fd has an exclusive lock on dev */
if (flags & O_NONBLOCK)
goto error_out;
res = 0;
__wait_event_interruptible(sdp->o_excl_wait, (!sdp->exclude),
res);
if (res) {
retval = res; /* -ERESTARTSYS because signal hit process */
goto error_out;
}
}
if (sdp->detached) {
retval = -ENODEV;
goto error_out;
}
if (!sdp->headfp) { /* no existing opens on this device */
sdp->sgdebug = 0;
sdp->sg_tablesize = sdp->device->host->sg_tablesize;
}
if ((sfp = sg_add_sfp(sdp, dev)))
filp->private_data = sfp;
else {
if (flags & O_EXCL)
sdp->exclude = 0; /* undo if error */
retval = -ENOMEM;
goto error_out;
}
return 0;
error_out:
scsi_device_put(sdp->device);
return retval;
}
/* Following function was formerly called 'sg_close' */
static int
sg_release(struct inode *inode, struct file *filp)
{
Sg_device *sdp;
Sg_fd *sfp;
if ((!(sfp = (Sg_fd *) filp->private_data)) || (!(sdp = sfp->parentdp)))
return -ENXIO;
SCSI_LOG_TIMEOUT(3, printk("sg_release: %s\n", sdp->disk->disk_name));
sg_fasync(-1, filp, 0); /* remove filp from async notification list */
if (0 == sg_remove_sfp(sdp, sfp)) { /* Returns 1 when sdp gone */
if (!sdp->detached) {
scsi_device_put(sdp->device);
}
sdp->exclude = 0;
wake_up_interruptible(&sdp->o_excl_wait);
}
return 0;
}
static ssize_t
sg_read(struct file *filp, char *buf, size_t count, loff_t * ppos)
{
int k, res;
Sg_device *sdp;
Sg_fd *sfp;
Sg_request *srp;
int req_pack_id = -1;
struct sg_header old_hdr;
sg_io_hdr_t new_hdr;
sg_io_hdr_t *hp;
if ((!(sfp = (Sg_fd *) filp->private_data)) || (!(sdp = sfp->parentdp)))
return -ENXIO;
SCSI_LOG_TIMEOUT(3, printk("sg_read: %s, count=%d\n",
sdp->disk->disk_name, (int) count));
if (ppos != &filp->f_pos) ; /* FIXME: Hmm. Seek to the right place, or fail? */
if ((k = verify_area(VERIFY_WRITE, buf, count)))
return k;
if (sfp->force_packid && (count >= SZ_SG_HEADER)) {
if (__copy_from_user(&old_hdr, buf, SZ_SG_HEADER))
return -EFAULT;
if (old_hdr.reply_len < 0) {
if (count >= SZ_SG_IO_HDR) {
if (__copy_from_user
(&new_hdr, buf, SZ_SG_IO_HDR))
return -EFAULT;
req_pack_id = new_hdr.pack_id;
}
} else
req_pack_id = old_hdr.pack_id;
}
srp = sg_get_rq_mark(sfp, req_pack_id);
if (!srp) { /* now wait on packet to arrive */
if (sdp->detached)
return -ENODEV;
if (filp->f_flags & O_NONBLOCK)
return -EAGAIN;
while (1) {
res = 0; /* following is a macro that beats race condition */
__wait_event_interruptible(sfp->read_wait,
(sdp->detached || (srp = sg_get_rq_mark(sfp, req_pack_id))),
res);
if (sdp->detached)
return -ENODEV;
if (0 == res)
break;
return res; /* -ERESTARTSYS because signal hit process */
}
}
if (srp->header.interface_id != '\0')
return sg_new_read(sfp, buf, count, srp);
hp = &srp->header;
memset(&old_hdr, 0, SZ_SG_HEADER);
old_hdr.reply_len = (int) hp->timeout;
old_hdr.pack_len = old_hdr.reply_len; /* very old, strange behaviour */
old_hdr.pack_id = hp->pack_id;
old_hdr.twelve_byte =
((srp->data.cmd_opcode >= 0xc0) && (12 == hp->cmd_len)) ? 1 : 0;
old_hdr.target_status = hp->masked_status;
old_hdr.host_status = hp->host_status;
old_hdr.driver_status = hp->driver_status;
if ((CHECK_CONDITION & hp->masked_status) ||
(DRIVER_SENSE & hp->driver_status))
memcpy(old_hdr.sense_buffer, srp->sense_b,
sizeof (old_hdr.sense_buffer));
switch (hp->host_status) {
/* This setup of 'result' is for backward compatibility and is best
ignored by the user who should use target, host + driver status */
case DID_OK:
case DID_PASSTHROUGH:
case DID_SOFT_ERROR:
old_hdr.result = 0;
break;
case DID_NO_CONNECT:
case DID_BUS_BUSY:
case DID_TIME_OUT:
old_hdr.result = EBUSY;
break;
case DID_BAD_TARGET:
case DID_ABORT:
case DID_PARITY:
case DID_RESET:
case DID_BAD_INTR:
old_hdr.result = EIO;
break;
case DID_ERROR:
old_hdr.result = (srp->sense_b[0] == 0 &&
hp->masked_status == GOOD) ? 0 : EIO;
break;
default:
old_hdr.result = EIO;
break;
}
/* Now copy the result back to the user buffer. */
if (count >= SZ_SG_HEADER) {
if (__copy_to_user(buf, &old_hdr, SZ_SG_HEADER))
return -EFAULT;
buf += SZ_SG_HEADER;
if (count > old_hdr.reply_len)
count = old_hdr.reply_len;
if (count > SZ_SG_HEADER) {
if ((res =
sg_read_oxfer(srp, buf, count - SZ_SG_HEADER)))
return -EFAULT;
}
} else
count = (old_hdr.result == 0) ? 0 : -EIO;
sg_finish_rem_req(srp);
return count;
}
static ssize_t
sg_new_read(Sg_fd * sfp, char *buf, size_t count, Sg_request * srp)
{
sg_io_hdr_t *hp = &srp->header;
int err = 0;
int len;
if (count < SZ_SG_IO_HDR) {
err = -EINVAL;
goto err_out;
}
hp->sb_len_wr = 0;
if ((hp->mx_sb_len > 0) && hp->sbp) {
if ((CHECK_CONDITION & hp->masked_status) ||
(DRIVER_SENSE & hp->driver_status)) {
int sb_len = sizeof (dummy_cmdp->sr_sense_buffer);
sb_len = (hp->mx_sb_len > sb_len) ? sb_len : hp->mx_sb_len;
len = 8 + (int) srp->sense_b[7]; /* Additional sense length field */
len = (len > sb_len) ? sb_len : len;
if (copy_to_user(hp->sbp, srp->sense_b, len)) {
err = -EFAULT;
goto err_out;
}
hp->sb_len_wr = len;
}
}
if (hp->masked_status || hp->host_status || hp->driver_status)
hp->info |= SG_INFO_CHECK;
if (copy_to_user(buf, hp, SZ_SG_IO_HDR)) {
err = -EFAULT;
goto err_out;
}
err = sg_read_xfer(srp);
err_out:
sg_finish_rem_req(srp);
return (0 == err) ? count : err;
}
static ssize_t
sg_write(struct file *filp, const char *buf, size_t count, loff_t * ppos)
{
int mxsize, cmd_size, k;
int input_size, blocking;
unsigned char opcode;
Sg_device *sdp;
Sg_fd *sfp;
Sg_request *srp;
struct sg_header old_hdr;
sg_io_hdr_t *hp;
unsigned char cmnd[sizeof (dummy_cmdp->sr_cmnd)];
if ((!(sfp = (Sg_fd *) filp->private_data)) || (!(sdp = sfp->parentdp)))
return -ENXIO;
SCSI_LOG_TIMEOUT(3, printk("sg_write: %s, count=%d\n",
sdp->disk->disk_name, (int) count));
if (sdp->detached)
return -ENODEV;
if (!((filp->f_flags & O_NONBLOCK) ||
scsi_block_when_processing_errors(sdp->device)))
return -ENXIO;
if (ppos != &filp->f_pos) ; /* FIXME: Hmm. Seek to the right place, or fail? */
if ((k = verify_area(VERIFY_READ, buf, count)))
return k; /* protects following copy_from_user()s + get_user()s */
if (count < SZ_SG_HEADER)
return -EIO;
if (__copy_from_user(&old_hdr, buf, SZ_SG_HEADER))
return -EFAULT;
blocking = !(filp->f_flags & O_NONBLOCK);
if (old_hdr.reply_len < 0)
return sg_new_write(sfp, buf, count, blocking, 0, NULL);
if (count < (SZ_SG_HEADER + 6))
return -EIO; /* The minimum scsi command length is 6 bytes. */
if (!(srp = sg_add_request(sfp))) {
SCSI_LOG_TIMEOUT(1, printk("sg_write: queue full\n"));
return -EDOM;
}
buf += SZ_SG_HEADER;
__get_user(opcode, buf);
if (sfp->next_cmd_len > 0) {
if (sfp->next_cmd_len > MAX_COMMAND_SIZE) {
SCSI_LOG_TIMEOUT(1, printk("sg_write: command length too long\n"));
sfp->next_cmd_len = 0;
sg_remove_request(sfp, srp);
return -EIO;
}
cmd_size = sfp->next_cmd_len;
sfp->next_cmd_len = 0; /* reset so only this write() effected */
} else {
cmd_size = COMMAND_SIZE(opcode); /* based on SCSI command group */
if ((opcode >= 0xc0) && old_hdr.twelve_byte)
cmd_size = 12;
}
SCSI_LOG_TIMEOUT(4, printk(
"sg_write: scsi opcode=0x%02x, cmd_size=%d\n", (int) opcode, cmd_size));
/* Determine buffer size. */
input_size = count - cmd_size;
mxsize = (input_size > old_hdr.reply_len) ? input_size : old_hdr.reply_len;
mxsize -= SZ_SG_HEADER;
input_size -= SZ_SG_HEADER;
if (input_size < 0) {
sg_remove_request(sfp, srp);
return -EIO; /* User did not pass enough bytes for this command. */
}
hp = &srp->header;
hp->interface_id = '\0'; /* indicator of old interface tunnelled */
hp->cmd_len = (unsigned char) cmd_size;
hp->iovec_count = 0;
hp->mx_sb_len = 0;
if (input_size > 0)
hp->dxfer_direction = (old_hdr.reply_len > SZ_SG_HEADER) ?
SG_DXFER_TO_FROM_DEV : SG_DXFER_TO_DEV;
else
hp->dxfer_direction = (mxsize > 0) ? SG_DXFER_FROM_DEV : SG_DXFER_NONE;
hp->dxfer_len = mxsize;
hp->dxferp = (unsigned char *) buf + cmd_size;
hp->sbp = NULL;
hp->timeout = old_hdr.reply_len; /* structure abuse ... */
hp->flags = input_size; /* structure abuse ... */
hp->pack_id = old_hdr.pack_id;
hp->usr_ptr = NULL;
if (__copy_from_user(cmnd, buf, cmd_size))
return -EFAULT;
k = sg_common_write(sfp, srp, cmnd, sfp->timeout, blocking);
return (k < 0) ? k : count;
}
static ssize_t
sg_new_write(Sg_fd * sfp, const char *buf, size_t count,
int blocking, int read_only, Sg_request ** o_srp)
{
int k;
Sg_request *srp;
sg_io_hdr_t *hp;
unsigned char cmnd[sizeof (dummy_cmdp->sr_cmnd)];
int timeout;
if (count < SZ_SG_IO_HDR)
return -EINVAL;
if ((k = verify_area(VERIFY_READ, buf, count)))
return k; /* protects following copy_from_user()s + get_user()s */
sfp->cmd_q = 1; /* when sg_io_hdr seen, set command queuing on */
if (!(srp = sg_add_request(sfp))) {
SCSI_LOG_TIMEOUT(1, printk("sg_new_write: queue full\n"));
return -EDOM;
}
hp = &srp->header;
if (__copy_from_user(hp, buf, SZ_SG_IO_HDR)) {
sg_remove_request(sfp, srp);
return -EFAULT;
}
if (hp->interface_id != 'S') {
sg_remove_request(sfp, srp);
return -ENOSYS;
}
if (hp->flags & SG_FLAG_MMAP_IO) {
if (hp->dxfer_len > sfp->reserve.bufflen) {
sg_remove_request(sfp, srp);
return -ENOMEM; /* MMAP_IO size must fit in reserve buffer */
}
if (hp->flags & SG_FLAG_DIRECT_IO) {
sg_remove_request(sfp, srp);
return -EINVAL; /* either MMAP_IO or DIRECT_IO (not both) */
}
if (sg_res_in_use(sfp)) {
sg_remove_request(sfp, srp);
return -EBUSY; /* reserve buffer already being used */
}
}
timeout = sg_ms_to_jif(srp->header.timeout);
if ((!hp->cmdp) || (hp->cmd_len < 6) || (hp->cmd_len > sizeof (cmnd))) {
sg_remove_request(sfp, srp);
return -EMSGSIZE;
}
if ((k = verify_area(VERIFY_READ, hp->cmdp, hp->cmd_len))) {
sg_remove_request(sfp, srp);
return k; /* protects following copy_from_user()s + get_user()s */
}
if (__copy_from_user(cmnd, hp->cmdp, hp->cmd_len)) {
sg_remove_request(sfp, srp);
return -EFAULT;
}
if (read_only &&
(!sg_allow_access(cmnd[0], sfp->parentdp->device->type))) {
sg_remove_request(sfp, srp);
return -EPERM;
}
k = sg_common_write(sfp, srp, cmnd, timeout, blocking);
if (k < 0)
return k;
if (o_srp)
*o_srp = srp;
return count;
}
static int
sg_common_write(Sg_fd * sfp, Sg_request * srp,
unsigned char *cmnd, int timeout, int blocking)
{
int k;
Scsi_Request *SRpnt;
Sg_device *sdp = sfp->parentdp;
sg_io_hdr_t *hp = &srp->header;
request_queue_t *q;
srp->data.cmd_opcode = cmnd[0]; /* hold opcode of command */
hp->status = 0;
hp->masked_status = 0;
hp->msg_status = 0;
hp->info = 0;
hp->host_status = 0;
hp->driver_status = 0;
hp->resid = 0;
SCSI_LOG_TIMEOUT(4, printk("sg_common_write: scsi opcode=0x%02x, cmd_size=%d\n",
(int) cmnd[0], (int) hp->cmd_len));
if ((k = sg_start_req(srp))) {
SCSI_LOG_TIMEOUT(1, printk("sg_write: start_req err=%d\n", k));
sg_finish_rem_req(srp);
return k; /* probably out of space --> ENOMEM */
}
if ((k = sg_write_xfer(srp))) {
SCSI_LOG_TIMEOUT(1, printk("sg_write: write_xfer, bad address\n"));
sg_finish_rem_req(srp);
return k;
}
if (sdp->detached) {
sg_finish_rem_req(srp);
return -ENODEV;
}
SRpnt = scsi_allocate_request(sdp->device);
if (SRpnt == NULL) {
SCSI_LOG_TIMEOUT(1, printk("sg_write: no mem\n"));
sg_finish_rem_req(srp);
return -ENOMEM;
}
srp->my_cmdp = SRpnt;
q = SRpnt->sr_device->request_queue;
SRpnt->sr_request->rq_disk = sdp->disk;
SRpnt->sr_sense_buffer[0] = 0;
SRpnt->sr_cmd_len = hp->cmd_len;
SRpnt->sr_use_sg = srp->data.k_use_sg;
SRpnt->sr_sglist_len = srp->data.sglist_len;
SRpnt->sr_bufflen = srp->data.bufflen;
SRpnt->sr_underflow = 0;
SRpnt->sr_buffer = srp->data.buffer;
switch (hp->dxfer_direction) {
case SG_DXFER_TO_FROM_DEV:
case SG_DXFER_FROM_DEV:
SRpnt->sr_data_direction = SCSI_DATA_READ;
break;
case SG_DXFER_TO_DEV:
SRpnt->sr_data_direction = SCSI_DATA_WRITE;
break;
case SG_DXFER_UNKNOWN:
SRpnt->sr_data_direction = SCSI_DATA_UNKNOWN;
break;
default:
SRpnt->sr_data_direction = SCSI_DATA_NONE;
break;
}
SRpnt->upper_private_data = srp;
srp->data.k_use_sg = 0;
srp->data.sglist_len = 0;
srp->data.bufflen = 0;
srp->data.buffer = NULL;
hp->duration = jiffies; /* unit jiffies now, millisecs after done */
/* Now send everything of to mid-level. The next time we hear about this
packet is when sg_cmd_done() is called (i.e. a callback). */
scsi_do_req(SRpnt, (void *) cmnd,
(void *) SRpnt->sr_buffer, hp->dxfer_len,
sg_cmd_done, timeout, SG_DEFAULT_RETRIES);
/* dxfer_len overwrites SRpnt->sr_bufflen, hence need for b_malloc_len */
generic_unplug_device(q);
return 0;
}
static int
sg_ioctl(struct inode *inode, struct file *filp,
unsigned int cmd_in, unsigned long arg)
{
int result, val, read_only;
Sg_device *sdp;
Sg_fd *sfp;
Sg_request *srp;
unsigned long iflags;
if ((!(sfp = (Sg_fd *) filp->private_data)) || (!(sdp = sfp->parentdp)))
return -ENXIO;
SCSI_LOG_TIMEOUT(3, printk("sg_ioctl: %s, cmd=0x%x\n",
sdp->disk->disk_name, (int) cmd_in));
read_only = (O_RDWR != (filp->f_flags & O_ACCMODE));
switch (cmd_in) {
case SG_IO:
{
int blocking = 1; /* ignore O_NONBLOCK flag */
if (sdp->detached)
return -ENODEV;
if (!scsi_block_when_processing_errors(sdp->device))
return -ENXIO;
result = verify_area(VERIFY_WRITE, (void *) arg,
SZ_SG_IO_HDR);
if (result)
return result;
result =
sg_new_write(sfp, (const char *) arg, SZ_SG_IO_HDR,
blocking, read_only, &srp);
if (result < 0)
return result;
srp->sg_io_owned = 1;
while (1) {
result = 0; /* following macro to beat race condition */
__wait_event_interruptible(sfp->read_wait,
(sdp->detached || sfp->closed || srp->done),
result);
if (sdp->detached)
return -ENODEV;
if (sfp->closed)
return 0; /* request packet dropped already */
if (0 == result)
break;
srp->orphan = 1;
return result; /* -ERESTARTSYS because signal hit process */
}
srp->done = 2;
result = sg_new_read(sfp, (char *) arg, SZ_SG_IO_HDR, srp);
return (result < 0) ? result : 0;
}
case SG_SET_TIMEOUT:
result = get_user(val, (int *) arg);
if (result)
return result;
if (val < 0)
return -EIO;
if (val >= MULDIV (INT_MAX, USER_HZ, HZ))
val = MULDIV (INT_MAX, USER_HZ, HZ);
sfp->timeout_user = val;
sfp->timeout = MULDIV (val, HZ, USER_HZ);
return 0;
case SG_GET_TIMEOUT: /* N.B. User receives timeout as return value */
/* strange ..., for backward compatibility */
return sfp->timeout_user;
case SG_SET_FORCE_LOW_DMA:
result = get_user(val, (int *) arg);
if (result)
return result;
if (val) {
sfp->low_dma = 1;
if ((0 == sfp->low_dma) && (0 == sg_res_in_use(sfp))) {
val = (int) sfp->reserve.bufflen;
sg_remove_scat(&sfp->reserve);
sg_build_reserve(sfp, val);
}
} else {
if (sdp->detached)
return -ENODEV;
sfp->low_dma = sdp->device->host->unchecked_isa_dma;
}
return 0;
case SG_GET_LOW_DMA:
return put_user((int) sfp->low_dma, (int *) arg);
case SG_GET_SCSI_ID:
result =
verify_area(VERIFY_WRITE, (void *) arg,
sizeof (sg_scsi_id_t));
if (result)
return result;
else {
sg_scsi_id_t *sg_idp = (sg_scsi_id_t *) arg;
if (sdp->detached)
return -ENODEV;
__put_user((int) sdp->device->host->host_no,
&sg_idp->host_no);
__put_user((int) sdp->device->channel,
&sg_idp->channel);
__put_user((int) sdp->device->id, &sg_idp->scsi_id);
__put_user((int) sdp->device->lun, &sg_idp->lun);
__put_user((int) sdp->device->type, &sg_idp->scsi_type);
__put_user((short) sdp->device->host->cmd_per_lun,
&sg_idp->h_cmd_per_lun);
__put_user((short) sdp->device->queue_depth,
&sg_idp->d_queue_depth);
__put_user(0, &sg_idp->unused[0]);
__put_user(0, &sg_idp->unused[1]);
return 0;
}
case SG_SET_FORCE_PACK_ID:
result = get_user(val, (int *) arg);
if (result)
return result;
sfp->force_packid = val ? 1 : 0;
return 0;
case SG_GET_PACK_ID:
result = verify_area(VERIFY_WRITE, (void *) arg, sizeof (int));
if (result)
return result;
read_lock_irqsave(&sfp->rq_list_lock, iflags);
for (srp = sfp->headrp; srp; srp = srp->nextrp) {
if ((1 == srp->done) && (!srp->sg_io_owned)) {
read_unlock_irqrestore(&sfp->rq_list_lock,
iflags);
__put_user(srp->header.pack_id, (int *) arg);
return 0;
}
}
read_unlock_irqrestore(&sfp->rq_list_lock, iflags);
__put_user(-1, (int *) arg);
return 0;
case SG_GET_NUM_WAITING:
read_lock_irqsave(&sfp->rq_list_lock, iflags);
for (val = 0, srp = sfp->headrp; srp; srp = srp->nextrp) {
if ((1 == srp->done) && (!srp->sg_io_owned))
++val;
}
read_unlock_irqrestore(&sfp->rq_list_lock, iflags);
return put_user(val, (int *) arg);
case SG_GET_SG_TABLESIZE:
return put_user(sdp->sg_tablesize, (int *) arg);
case SG_SET_RESERVED_SIZE:
result = get_user(val, (int *) arg);
if (result)
return result;
if (val != sfp->reserve.bufflen) {
if (sg_res_in_use(sfp) || sfp->mmap_called)
return -EBUSY;
sg_remove_scat(&sfp->reserve);
sg_build_reserve(sfp, val);
}
return 0;
case SG_GET_RESERVED_SIZE:
val = (int) sfp->reserve.bufflen;
return put_user(val, (int *) arg);
case SG_SET_COMMAND_Q:
result = get_user(val, (int *) arg);
if (result)
return result;
sfp->cmd_q = val ? 1 : 0;
return 0;
case SG_GET_COMMAND_Q:
return put_user((int) sfp->cmd_q, (int *) arg);
case SG_SET_KEEP_ORPHAN:
result = get_user(val, (int *) arg);
if (result)
return result;
sfp->keep_orphan = val;
return 0;
case SG_GET_KEEP_ORPHAN:
return put_user((int) sfp->keep_orphan, (int *) arg);
case SG_NEXT_CMD_LEN:
result = get_user(val, (int *) arg);
if (result)
return result;
sfp->next_cmd_len = (val > 0) ? val : 0;
return 0;
case SG_GET_VERSION_NUM:
return put_user(sg_version_num, (int *) arg);
case SG_GET_ACCESS_COUNT:
val = (sdp->device ? sdp->device->access_count : 0);
return put_user(val, (int *) arg);
case SG_GET_REQUEST_TABLE:
result = verify_area(VERIFY_WRITE, (void *) arg,
SZ_SG_REQ_INFO * SG_MAX_QUEUE);
if (result)
return result;
else {
sg_req_info_t rinfo[SG_MAX_QUEUE];
Sg_request *srp;
read_lock_irqsave(&sfp->rq_list_lock, iflags);
for (srp = sfp->headrp, val = 0; val < SG_MAX_QUEUE;
++val, srp = srp ? srp->nextrp : srp) {
memset(&rinfo[val], 0, SZ_SG_REQ_INFO);
if (srp) {
rinfo[val].req_state = srp->done + 1;
rinfo[val].problem =
srp->header.masked_status &
srp->header.host_status &
srp->header.driver_status;
rinfo[val].duration =
srp->done ? srp->header.duration :
sg_jif_to_ms(
jiffies - srp->header.duration);
rinfo[val].orphan = srp->orphan;
rinfo[val].sg_io_owned = srp->sg_io_owned;
rinfo[val].pack_id = srp->header.pack_id;
rinfo[val].usr_ptr = srp->header.usr_ptr;
}
}
read_unlock_irqrestore(&sfp->rq_list_lock, iflags);
return (__copy_to_user((void *) arg, rinfo,
SZ_SG_REQ_INFO * SG_MAX_QUEUE) ? -EFAULT : 0);
}
case SG_EMULATED_HOST:
if (sdp->detached)
return -ENODEV;
return put_user(sdp->device->host->hostt->emulated, (int *) arg);
case SG_SCSI_RESET:
if (sdp->detached)
return -ENODEV;
if (filp->f_flags & O_NONBLOCK) {
if (sdp->device->host->in_recovery)
return -EBUSY;
} else if (!scsi_block_when_processing_errors(sdp->device))
return -EBUSY;
result = get_user(val, (int *) arg);
if (result)
return result;
if (SG_SCSI_RESET_NOTHING == val)
return 0;
switch (val) {
case SG_SCSI_RESET_DEVICE:
val = SCSI_TRY_RESET_DEVICE;
break;
case SG_SCSI_RESET_BUS:
val = SCSI_TRY_RESET_BUS;
break;
case SG_SCSI_RESET_HOST:
val = SCSI_TRY_RESET_HOST;
break;
default:
return -EINVAL;
}
if (!capable(CAP_SYS_ADMIN) || !capable(CAP_SYS_RAWIO))
return -EACCES;
return (scsi_reset_provider(sdp->device, val) ==
SUCCESS) ? 0 : -EIO;
case SCSI_IOCTL_SEND_COMMAND:
if (sdp->detached)
return -ENODEV;
if (read_only) {
unsigned char opcode = WRITE_6;
Scsi_Ioctl_Command *siocp = (void *) arg;
if (copy_from_user(&opcode, siocp->data, 1))
return -EFAULT;
if (!sg_allow_access(opcode, sdp->device->type))
return -EPERM;
}
return scsi_ioctl_send_command(sdp->device, (void *) arg);
case SG_SET_DEBUG:
result = get_user(val, (int *) arg);
if (result)
return result;
sdp->sgdebug = (char) val;
return 0;
case SCSI_IOCTL_GET_IDLUN:
case SCSI_IOCTL_GET_BUS_NUMBER:
case SCSI_IOCTL_PROBE_HOST:
case SG_GET_TRANSFORM:
if (sdp->detached)
return -ENODEV;
return scsi_ioctl(sdp->device, cmd_in, (void *) arg);
default:
if (read_only)
return -EPERM; /* don't know so take safe approach */
return scsi_ioctl(sdp->device, cmd_in, (void *) arg);
}
}
static unsigned int
sg_poll(struct file *filp, poll_table * wait)
{
unsigned int res = 0;
Sg_device *sdp;
Sg_fd *sfp;
Sg_request *srp;
int count = 0;
unsigned long iflags;
if ((!(sfp = (Sg_fd *) filp->private_data)) || (!(sdp = sfp->parentdp))
|| sfp->closed)
return POLLERR;
poll_wait(filp, &sfp->read_wait, wait);
read_lock_irqsave(&sfp->rq_list_lock, iflags);
for (srp = sfp->headrp; srp; srp = srp->nextrp) {
/* if any read waiting, flag it */
if ((0 == res) && (1 == srp->done) && (!srp->sg_io_owned))
res = POLLIN | POLLRDNORM;
++count;
}
read_unlock_irqrestore(&sfp->rq_list_lock, iflags);
if (sdp->detached)
res |= POLLHUP;
else if (!sfp->cmd_q) {
if (0 == count)
res |= POLLOUT | POLLWRNORM;
} else if (count < SG_MAX_QUEUE)
res |= POLLOUT | POLLWRNORM;
SCSI_LOG_TIMEOUT(3, printk("sg_poll: %s, res=0x%x\n",
sdp->disk->disk_name, (int) res));
return res;
}
static int
sg_fasync(int fd, struct file *filp, int mode)
{
int retval;
Sg_device *sdp;
Sg_fd *sfp;
if ((!(sfp = (Sg_fd *) filp->private_data)) || (!(sdp = sfp->parentdp)))
return -ENXIO;
SCSI_LOG_TIMEOUT(3, printk("sg_fasync: %s, mode=%d\n",
sdp->disk->disk_name, mode));
retval = fasync_helper(fd, filp, mode, &sfp->async_qp);
return (retval < 0) ? retval : 0;
}
static inline unsigned char *
sg_scatg2virt(const struct scatterlist *sclp)
{
return (sclp && sclp->page) ?
(unsigned char *) page_address(sclp->page) + sclp->offset : NULL;
}
/* When startFinish==1 increments page counts for pages other than the
first of scatter gather elements obtained from __get_free_pages().
When startFinish==0 decrements ... */
static void
sg_rb_correct4mmap(Sg_scatter_hold * rsv_schp, int startFinish)
{
void *page_ptr;
struct page *page;
int k, m;
SCSI_LOG_TIMEOUT(3, printk("sg_rb_correct4mmap: startFinish=%d, scatg=%d\n",
startFinish, rsv_schp->k_use_sg));
/* N.B. correction _not_ applied to base page of each allocation */
if (rsv_schp->k_use_sg) { /* reserve buffer is a scatter gather list */
struct scatterlist *sclp = rsv_schp->buffer;
for (k = 0; k < rsv_schp->k_use_sg; ++k, ++sclp) {
for (m = PAGE_SIZE; m < sclp->length; m += PAGE_SIZE) {
page_ptr = sg_scatg2virt(sclp) + m;
page = virt_to_page(page_ptr);
if (startFinish)
atomic_inc(&page->count);
else {
if (page_count(page) > 0)
atomic_dec(&page->count);
}
}
}
} else { /* reserve buffer is just a single allocation */
for (m = PAGE_SIZE; m < rsv_schp->bufflen; m += PAGE_SIZE) {
page_ptr = (unsigned char *) rsv_schp->buffer + m;
page = virt_to_page(page_ptr);
if (startFinish)
atomic_inc(&page->count);
else {
if (page_count(page) > 0)
atomic_dec(&page->count);
}
}
}
}
static struct page *
sg_vma_nopage(struct vm_area_struct *vma, unsigned long addr, int unused)
{
Sg_fd *sfp;
struct page *page = NOPAGE_SIGBUS;
void *page_ptr = NULL;
unsigned long offset;
Sg_scatter_hold *rsv_schp;
if ((NULL == vma) || (!(sfp = (Sg_fd *) vma->vm_private_data)))
return page;
rsv_schp = &sfp->reserve;
offset = addr - vma->vm_start;
if (offset >= rsv_schp->bufflen)
return page;
SCSI_LOG_TIMEOUT(3, printk("sg_vma_nopage: offset=%lu, scatg=%d\n",
offset, rsv_schp->k_use_sg));
if (rsv_schp->k_use_sg) { /* reserve buffer is a scatter gather list */
int k;
unsigned long sa = vma->vm_start;
unsigned long len;
struct scatterlist *sclp = rsv_schp->buffer;
for (k = 0; (k < rsv_schp->k_use_sg) && (sa < vma->vm_end);
++k, ++sclp) {
len = vma->vm_end - sa;
len = (len < sclp->length) ? len : sclp->length;
if (offset < len) {
page_ptr = sg_scatg2virt(sclp) + offset;
page = virt_to_page(page_ptr);
get_page(page); /* increment page count */
break;
}
sa += len;
offset -= len;
}
} else { /* reserve buffer is just a single allocation */
page_ptr = (unsigned char *) rsv_schp->buffer + offset;
page = virt_to_page(page_ptr);
get_page(page); /* increment page count */
}
return page;
}
static struct vm_operations_struct sg_mmap_vm_ops = {
.nopage = sg_vma_nopage,
};
static int
sg_mmap(struct file *filp, struct vm_area_struct *vma)
{
Sg_fd *sfp;
unsigned long req_sz = vma->vm_end - vma->vm_start;
Sg_scatter_hold *rsv_schp;
if ((!filp) || (!vma) || (!(sfp = (Sg_fd *) filp->private_data)))
return -ENXIO;
SCSI_LOG_TIMEOUT(3, printk("sg_mmap starting, vm_start=%p, len=%d\n",
(void *) vma->vm_start, (int) req_sz));
if (vma->vm_pgoff)
return -EINVAL; /* want no offset */
rsv_schp = &sfp->reserve;
if (req_sz > rsv_schp->bufflen)
return -ENOMEM; /* cannot map more than reserved buffer */
if (rsv_schp->k_use_sg) { /* reserve buffer is a scatter gather list */
int k;
unsigned long sa = vma->vm_start;
unsigned long len;
struct scatterlist *sclp = rsv_schp->buffer;
for (k = 0; (k < rsv_schp->k_use_sg) && (sa < vma->vm_end);
++k, ++sclp) {
if (0 != sclp->offset)
return -EFAULT; /* non page aligned memory ?? */
len = vma->vm_end - sa;
len = (len < sclp->length) ? len : sclp->length;
sa += len;
}
} else { /* reserve buffer is just a single allocation */
if ((unsigned long) rsv_schp->buffer & (PAGE_SIZE - 1))
return -EFAULT; /* non page aligned memory ?? */
}
if (0 == sfp->mmap_called) {
sg_rb_correct4mmap(rsv_schp, 1); /* do only once per fd lifetime */
sfp->mmap_called = 1;
}
vma->vm_flags |= (VM_RESERVED | VM_IO);
vma->vm_private_data = sfp;
vma->vm_ops = &sg_mmap_vm_ops;
return 0;
}
/* This function is a "bottom half" handler that is called by the
* mid level when a command is completed (or has failed). */
static void
sg_cmd_done(Scsi_Cmnd * SCpnt)
{
Scsi_Request *SRpnt = NULL;
Sg_device *sdp = NULL;
Sg_fd *sfp;
Sg_request *srp = NULL;
if (SCpnt && (SRpnt = SCpnt->sc_request))
srp = (Sg_request *) SRpnt->upper_private_data;
if (NULL == srp) {
printk(KERN_ERR "sg_cmd_done: NULL request\n");
if (SRpnt)
scsi_release_request(SRpnt);
return;
}
sfp = srp->parentfp;
if (sfp)
sdp = sfp->parentdp;
if ((NULL == sdp) || sdp->detached) {
printk(KERN_INFO "sg_cmd_done: device detached\n");
scsi_release_request(SRpnt);
return;
}
/* First transfer ownership of data buffers to sg_device object. */
srp->data.k_use_sg = SRpnt->sr_use_sg;
srp->data.sglist_len = SRpnt->sr_sglist_len;
srp->data.bufflen = SRpnt->sr_bufflen;
srp->data.buffer = SRpnt->sr_buffer;
/* now clear out request structure */
SRpnt->sr_use_sg = 0;
SRpnt->sr_sglist_len = 0;
SRpnt->sr_bufflen = 0;
SRpnt->sr_buffer = NULL;
SRpnt->sr_underflow = 0;
SRpnt->sr_request->rq_disk = NULL; /* "sg" _disowns_ request blk */
srp->my_cmdp = NULL;
srp->done = 1;
SCSI_LOG_TIMEOUT(4, printk("sg_cmd_done: %s, pack_id=%d, res=0x%x\n",
sdp->disk->disk_name, srp->header.pack_id, (int) SRpnt->sr_result));
srp->header.resid = SCpnt->resid;
/* N.B. unit of duration changes here from jiffies to millisecs */
srp->header.duration =
sg_jif_to_ms(jiffies - (int) srp->header.duration);
if (0 != SRpnt->sr_result) {
memcpy(srp->sense_b, SRpnt->sr_sense_buffer,
sizeof (srp->sense_b));
srp->header.status = 0xff & SRpnt->sr_result;
srp->header.masked_status = status_byte(SRpnt->sr_result);
srp->header.msg_status = msg_byte(SRpnt->sr_result);
srp->header.host_status = host_byte(SRpnt->sr_result);
srp->header.driver_status = driver_byte(SRpnt->sr_result);
if ((sdp->sgdebug > 0) &&
((CHECK_CONDITION == srp->header.masked_status) ||
(COMMAND_TERMINATED == srp->header.masked_status)))
print_req_sense("sg_cmd_done", SRpnt);
/* Following if statement is a patch supplied by Eric Youngdale */
if (driver_byte(SRpnt->sr_result) != 0
&& (SRpnt->sr_sense_buffer[0] & 0x7f) == 0x70
&& (SRpnt->sr_sense_buffer[2] & 0xf) == UNIT_ATTENTION
&& sdp->device->removable) {
/* Detected disc change. Set the bit - this may be used if */
/* there are filesystems using this device. */
sdp->device->changed = 1;
}
}
/* Rely on write phase to clean out srp status values, so no "else" */
scsi_release_request(SRpnt);
SRpnt = NULL;
if (sfp->closed) { /* whoops this fd already released, cleanup */
SCSI_LOG_TIMEOUT(1, printk("sg_cmd_done: already closed, freeing ...\n"));
sg_finish_rem_req(srp);
srp = NULL;
if (NULL == sfp->headrp) {
SCSI_LOG_TIMEOUT(1, printk("sg...bh: already closed, final cleanup\n"));
if (0 == sg_remove_sfp(sdp, sfp)) { /* device still present */
scsi_device_put(sdp->device);
}
sfp = NULL;
}
} else if (srp && srp->orphan) {
if (sfp->keep_orphan)
srp->sg_io_owned = 0;
else {
sg_finish_rem_req(srp);
srp = NULL;
}
}
if (sfp && srp) {
/* Now wake up any sg_read() that is waiting for this packet. */
wake_up_interruptible(&sfp->read_wait);
kill_fasync(&sfp->async_qp, SIGPOLL, POLL_IN);
}
}
static struct file_operations sg_fops = {
.owner = THIS_MODULE,
.read = sg_read,
.write = sg_write,
.poll = sg_poll,
.ioctl = sg_ioctl,
.open = sg_open,
.mmap = sg_mmap,
.release = sg_release,
.fasync = sg_fasync,
};
/* Driverfs file support */
static ssize_t
sg_device_kdev_read(struct device *driverfs_dev, char *page)
{
Sg_device *sdp = list_entry(driverfs_dev, Sg_device, sg_driverfs_dev);
return sprintf(page, "%x\n", MKDEV(sdp->disk->major,
sdp->disk->first_minor));
}
static DEVICE_ATTR(kdev,S_IRUGO,sg_device_kdev_read,NULL);
static ssize_t
sg_device_type_read(struct device *driverfs_dev, char *page)
{
return sprintf(page, "CHR\n");
}
static DEVICE_ATTR(type,S_IRUGO,sg_device_type_read,NULL);
static int
sg_attach(Scsi_Device * scsidp)
{
struct gendisk *disk;
Sg_device *sdp = NULL;
unsigned long iflags;
char devfs_name[64];
int k, error;
disk = alloc_disk(1);
if (!disk)
return -ENOMEM;
error = scsi_slave_attach(scsidp);
if (error)
goto out_put;
write_lock_irqsave(&sg_dev_arr_lock, iflags);
if (sg_nr_dev >= sg_dev_max) { /* try to resize */
Sg_device **tmp_da;
int tmp_dev_max = sg_nr_dev + SG_DEV_ARR_LUMP;
write_unlock_irqrestore(&sg_dev_arr_lock, iflags);
tmp_da = (Sg_device **)vmalloc(
tmp_dev_max * sizeof(Sg_device *));
if (NULL == tmp_da) {
printk(KERN_ERR
"sg_attach: device array cannot be resized\n");
error = -ENOMEM;
goto out_detach;
}
write_lock_irqsave(&sg_dev_arr_lock, iflags);
memset(tmp_da, 0, tmp_dev_max * sizeof (Sg_device *));
memcpy(tmp_da, sg_dev_arr,
sg_dev_max * sizeof (Sg_device *));
vfree((char *) sg_dev_arr);
sg_dev_arr = tmp_da;
sg_dev_max = tmp_dev_max;
}
find_empty_slot:
for (k = 0; k < sg_dev_max; k++)
if (!sg_dev_arr[k])
break;
if (k > SG_MAX_DEVS_MASK) {
write_unlock_irqrestore(&sg_dev_arr_lock, iflags);
printk(KERN_WARNING
"Unable to attach sg device <%d, %d, %d, %d>"
" type=%d, minor number exceed %d\n",
scsidp->host->host_no, scsidp->channel, scsidp->id,
scsidp->lun, scsidp->type, SG_MAX_DEVS_MASK);
if (NULL != sdp)
vfree((char *) sdp);
error = -ENODEV;
goto out_detach;
}
if (k < sg_dev_max) {
if (NULL == sdp) {
write_unlock_irqrestore(&sg_dev_arr_lock, iflags);
sdp = (Sg_device *)vmalloc(sizeof(Sg_device));
write_lock_irqsave(&sg_dev_arr_lock, iflags);
if (!sg_dev_arr[k])
goto find_empty_slot;
}
} else
sdp = NULL;
if (NULL == sdp) {
write_unlock_irqrestore(&sg_dev_arr_lock, iflags);
printk(KERN_ERR "sg_attach: Sg_device cannot be allocated\n");
error = -ENOMEM;
goto out_detach;
}
SCSI_LOG_TIMEOUT(3, printk("sg_attach: dev=%d \n", k));
memset(sdp, 0, sizeof(*sdp));
sdp->driver = &sg_template;
disk->private_data = &sdp->driver;
sprintf(disk->disk_name, "sg%d", k);
disk->major = SCSI_GENERIC_MAJOR;
disk->first_minor = k;
sdp->disk = disk;
sdp->device = scsidp;
init_waitqueue_head(&sdp->o_excl_wait);
sdp->headfp = NULL;
sdp->exclude = 0;
sdp->sgdebug = 0;
sdp->detached = 0;
sdp->sg_tablesize = scsidp->host ? scsidp->host->sg_tablesize : 0;
memset(&sdp->sg_driverfs_dev, 0, sizeof (struct device));
snprintf(sdp->sg_driverfs_dev.bus_id, BUS_ID_SIZE, "%s:gen",
scsidp->sdev_driverfs_dev.bus_id);
snprintf(sdp->sg_driverfs_dev.name, DEVICE_NAME_SIZE, "%sgeneric",
scsidp->sdev_driverfs_dev.name);
sdp->sg_driverfs_dev.parent = &scsidp->sdev_driverfs_dev;
sdp->sg_driverfs_dev.bus = scsidp->sdev_driverfs_dev.bus;
sg_nr_dev++;
sg_dev_arr[k] = sdp;
write_unlock_irqrestore(&sg_dev_arr_lock, iflags);
device_register(&sdp->sg_driverfs_dev);
device_create_file(&sdp->sg_driverfs_dev, &dev_attr_type);
device_create_file(&sdp->sg_driverfs_dev, &dev_attr_kdev);
sprintf(devfs_name, "%s/generic", scsidp->devfs_name);
devfs_register(NULL, devfs_name, 0,
SCSI_GENERIC_MAJOR, k,
S_IFCHR | S_IRUSR | S_IWUSR | S_IRGRP,
&sg_fops, sdp);
switch (scsidp->type) {
case TYPE_DISK:
case TYPE_MOD:
case TYPE_ROM:
case TYPE_WORM:
case TYPE_TAPE:
break;
default:
printk(KERN_NOTICE
"Attached scsi generic sg%d at scsi%d, channel"
" %d, id %d, lun %d, type %d\n", k,
scsidp->host->host_no, scsidp->channel, scsidp->id,
scsidp->lun, scsidp->type);
}
return 0;
out_detach:
scsi_slave_detach(scsidp);
out_put:
put_disk(disk);
return error;
}
static void
sg_detach(Scsi_Device * scsidp)
{
Sg_device *sdp = NULL;
unsigned long iflags;
Sg_fd *sfp;
Sg_fd *tsfp;
Sg_request *srp;
Sg_request *tsrp;
int k, delay;
if (NULL == sg_dev_arr)
return;
delay = 0;
write_lock_irqsave(&sg_dev_arr_lock, iflags);
for (k = 0; k < sg_dev_max; k++) {
sdp = sg_dev_arr[k];
if ((NULL == sdp) || (sdp->device != scsidp))
continue; /* dirty but lowers nesting */
if (sdp->headfp) {
sdp->detached = 1;
for (sfp = sdp->headfp; sfp; sfp = tsfp) {
tsfp = sfp->nextfp;
for (srp = sfp->headrp; srp; srp = tsrp) {
tsrp = srp->nextrp;
if (sfp->closed || (0 == srp->done))
sg_finish_rem_req(srp);
}
if (sfp->closed) {
scsi_device_put(sdp->device);
__sg_remove_sfp(sdp, sfp);
} else {
delay = 1;
wake_up_interruptible(&sfp->read_wait);
kill_fasync(&sfp->async_qp, SIGPOLL,
POLL_HUP);
}
}
SCSI_LOG_TIMEOUT(3, printk("sg_detach: dev=%d, dirty\n", k));
if (NULL == sdp->headfp) {
sg_dev_arr[k] = NULL;
}
} else { /* nothing active, simple case */
SCSI_LOG_TIMEOUT(3, printk("sg_detach: dev=%d\n", k));
sg_dev_arr[k] = NULL;
}
scsi_slave_detach(scsidp);
sg_nr_dev--;
break;
}
write_unlock_irqrestore(&sg_dev_arr_lock, iflags);
if (sdp) {
devfs_remove("%s/generic", scsidp->devfs_name);
device_remove_file(&sdp->sg_driverfs_dev, &dev_attr_type);
device_remove_file(&sdp->sg_driverfs_dev, &dev_attr_kdev);
device_unregister(&sdp->sg_driverfs_dev);
put_disk(sdp->disk);
sdp->disk = NULL;
if (NULL == sdp->headfp)
vfree((char *) sdp);
}
if (delay)
scsi_sleep(2); /* dirty detach so delay device destruction */
}
/* Set 'perm' (4th argument) to 0 to disable module_param's definition
* of sysfs parameters (which module_param doesn't yet support).
* Sysfs parameters defined explicitly below.
*/
module_param_named(def_reserved_size, def_reserved_size, int, 0);
module_param_named(allow_dio, sg_allow_dio, int, 0);
MODULE_AUTHOR("Douglas Gilbert");
MODULE_DESCRIPTION("SCSI generic (sg) driver");
MODULE_LICENSE("GPL");
MODULE_PARM_DESC(def_reserved_size, "size of buffer reserved for each fd");
static ssize_t sg_allow_dio_show(struct device_driver * ddp, char * buf)
{
return snprintf(buf, PAGE_SIZE, "%d\n", sg_allow_dio);
}
static ssize_t sg_allow_dio_store(struct device_driver * ddp,
const char * buf, size_t count)
{
if (1 == sscanf(buf, "%d", &sg_allow_dio)) {
sg_allow_dio = sg_allow_dio ? 1 : 0;
return count;
}
return -EINVAL;
}
DRIVER_ATTR(allow_dio, S_IRUGO | S_IWUSR, sg_allow_dio_show,
sg_allow_dio_store)
static ssize_t sg_def_reserved_show(struct device_driver * ddp, char * buf)
{
return snprintf(buf, PAGE_SIZE, "%d\n", sg_big_buff);
}
static ssize_t sg_def_reserved_store(struct device_driver * ddp,
const char * buf, size_t count)
{
if (1 == sscanf(buf, "%d", &def_reserved_size)) {
if (def_reserved_size >= 0) {
sg_big_buff = def_reserved_size;
return count;
}
}
return -EINVAL;
}
DRIVER_ATTR(def_reserved_size, S_IRUGO | S_IWUSR, sg_def_reserved_show,
sg_def_reserved_store)
static ssize_t sg_version_show(struct device_driver * ddp, char * buf)
{
return snprintf(buf, PAGE_SIZE, "%s\n", sg_version_str);
}
DRIVER_ATTR(version, S_IRUGO, sg_version_show, NULL)
static void do_create_driverfs_files(void)
{
struct device_driver * driverfs = &sg_template.scsi_driverfs_driver;
driver_create_file(driverfs, &driver_attr_allow_dio);
driver_create_file(driverfs, &driver_attr_def_reserved_size);
driver_create_file(driverfs, &driver_attr_version);
}
static void do_remove_driverfs_files(void)
{
struct device_driver * driverfs = &sg_template.scsi_driverfs_driver;
driver_remove_file(driverfs, &driver_attr_version);
driver_remove_file(driverfs, &driver_attr_def_reserved_size);
driver_remove_file(driverfs, &driver_attr_allow_dio);
}
static int __init
init_sg(void)
{
int rc;
if (def_reserved_size >= 0)
sg_big_buff = def_reserved_size;
rc = register_chrdev(SCSI_GENERIC_MAJOR, "sg", &sg_fops);
if (rc)
return rc;
rc = scsi_register_device(&sg_template);
if (rc)
return rc;
#ifdef CONFIG_PROC_FS
sg_proc_init();
#endif /* CONFIG_PROC_FS */
do_create_driverfs_files();
return 0;
}
static void __exit
exit_sg(void)
{
do_remove_driverfs_files();
#ifdef CONFIG_PROC_FS
sg_proc_cleanup();
#endif /* CONFIG_PROC_FS */
scsi_unregister_device(&sg_template);
unregister_chrdev(SCSI_GENERIC_MAJOR, "sg");
if (sg_dev_arr != NULL) {
vfree((char *) sg_dev_arr);
sg_dev_arr = NULL;
}
sg_dev_max = 0;
}
static int
sg_start_req(Sg_request * srp)
{
int res;
Sg_fd *sfp = srp->parentfp;
sg_io_hdr_t *hp = &srp->header;
int dxfer_len = (int) hp->dxfer_len;
int dxfer_dir = hp->dxfer_direction;
Sg_scatter_hold *req_schp = &srp->data;
Sg_scatter_hold *rsv_schp = &sfp->reserve;
SCSI_LOG_TIMEOUT(4, printk("sg_start_req: dxfer_len=%d\n", dxfer_len));
if ((dxfer_len <= 0) || (dxfer_dir == SG_DXFER_NONE))
return 0;
if (sg_allow_dio && (hp->flags & SG_FLAG_DIRECT_IO) &&
(dxfer_dir != SG_DXFER_UNKNOWN) && (0 == hp->iovec_count) &&
(!sfp->parentdp->device->host->unchecked_isa_dma)) {
res = sg_build_direct(srp, sfp, dxfer_len);
if (res <= 0) /* -ve -> error, 0 -> done, 1 -> try indirect */
return res;
}
if ((!sg_res_in_use(sfp)) && (dxfer_len <= rsv_schp->bufflen))
sg_link_reserve(sfp, srp, dxfer_len);
else {
res = sg_build_indirect(req_schp, sfp, dxfer_len);
if (res) {
sg_remove_scat(req_schp);
return res;
}
}
return 0;
}
static void
sg_finish_rem_req(Sg_request * srp)
{
Sg_fd *sfp = srp->parentfp;
Sg_scatter_hold *req_schp = &srp->data;
SCSI_LOG_TIMEOUT(4, printk("sg_finish_rem_req: res_used=%d\n", (int) srp->res_used));
// sg_unmap_and(&srp->data, 1);
if (srp->res_used)
sg_unlink_reserve(sfp, srp);
else
sg_remove_scat(req_schp);
sg_remove_request(sfp, srp);
}
static int
sg_build_sgat(Sg_scatter_hold * schp, const Sg_fd * sfp, int tablesize)
{
int ret_sz;
int elem_sz = sizeof (struct scatterlist);
int sg_bufflen = tablesize * elem_sz;
int mx_sc_elems = tablesize;
schp->buffer = sg_page_malloc(sg_bufflen, sfp->low_dma, &ret_sz);
if (!schp->buffer)
return -ENOMEM;
else if (ret_sz != sg_bufflen) {
sg_bufflen = ret_sz;
mx_sc_elems = sg_bufflen / elem_sz;
}
schp->sglist_len = sg_bufflen;
memset(schp->buffer, 0, sg_bufflen);
return mx_sc_elems; /* number of scat_gath elements allocated */
}
#ifdef SG_ALLOW_DIO_CODE
/* vvvvvvvv following code borrowed from st driver's direct IO vvvvvvvvv */
/* hopefully this generic code will moved to a library */
/* Pin down user pages and put them into a scatter gather list. Returns <= 0 if
- mapping of all pages not successful
- any page is above max_pfn
(i.e., either completely successful or fails)
*/
static int
st_map_user_pages(struct scatterlist *sgl, const unsigned int max_pages,
unsigned long uaddr, size_t count, int rw,
unsigned long max_pfn)
{
int res, i, j;
unsigned int nr_pages;
struct page **pages;
nr_pages = ((uaddr & ~PAGE_MASK) + count - 1 + ~PAGE_MASK) >> PAGE_SHIFT;
/* User attempted Overflow! */
if ((uaddr + count) < uaddr)
return -EINVAL;
/* Too big */
if (nr_pages > max_pages)
return -ENOMEM;
/* Hmm? */
if (count == 0)
return 0;
if ((pages = kmalloc(max_pages * sizeof(*pages), GFP_ATOMIC)) == NULL)
return -ENOMEM;
/* Try to fault in all of the necessary pages */
down_read(&current->mm->mmap_sem);
/* rw==READ means read from drive, write into memory area */
res = get_user_pages(
current,
current->mm,
uaddr,
nr_pages,
rw == READ,
0, /* don't force */
pages,
NULL);
up_read(&current->mm->mmap_sem);
/* Errors and no page mapped should return here */
if (res < nr_pages)
goto out_unmap;
for (i=0; i < nr_pages; i++) {
/* FIXME: flush superflous for rw==READ,
* probably wrong function for rw==WRITE
*/
flush_dcache_page(pages[i]);
if (page_to_pfn(pages[i]) > max_pfn)
goto out_unlock;
/* ?? Is locking needed? I don't think so */
/* if (TestSetPageLocked(pages[i]))
goto out_unlock; */
}
/* Populate the scatter/gather list */
sgl[0].page = pages[0];
sgl[0].offset = uaddr & ~PAGE_MASK;
if (nr_pages > 1) {
sgl[0].length = PAGE_SIZE - sgl[0].offset;
count -= sgl[0].length;
for (i=1; i < nr_pages ; i++) {
sgl[i].offset = 0;
sgl[i].page = pages[i];
sgl[i].length = count < PAGE_SIZE ? count : PAGE_SIZE;
count -= PAGE_SIZE;
}
}
else {
sgl[0].length = count;
}
kfree(pages);
return nr_pages;
out_unlock:
/* for (j=0; j < i; j++)
unlock_page(pages[j]); */
res = 0;
out_unmap:
if (res > 0)
for (j=0; j < res; j++)
page_cache_release(pages[j]);
kfree(pages);
return res;
}
/* And unmap them... */
static int
st_unmap_user_pages(struct scatterlist *sgl, const unsigned int nr_pages,
int dirtied)
{
int i;
for (i=0; i < nr_pages; i++) {
if (dirtied && !PageReserved(sgl[i].page))
SetPageDirty(sgl[i].page);
/* unlock_page(sgl[i].page); */
/* FIXME: cache flush missing for rw==READ
* FIXME: call the correct reference counting function
*/
page_cache_release(sgl[i].page);
}
return 0;
}
/* ^^^^^^^^ above code borrowed from st driver's direct IO ^^^^^^^^^ */
#endif
/* Returns: -ve -> error, 0 -> done, 1 -> try indirect */
static int
sg_build_direct(Sg_request * srp, Sg_fd * sfp, int dxfer_len)
{
#ifdef SG_ALLOW_DIO_CODE
sg_io_hdr_t *hp = &srp->header;
Sg_scatter_hold *schp = &srp->data;
int sg_tablesize = sfp->parentdp->sg_tablesize;
struct scatterlist *sgl;
int mx_sc_elems, res;
mx_sc_elems = sg_build_sgat(schp, sfp, sg_tablesize);
if (mx_sc_elems <= 0) {
return 1;
}
sgl = (struct scatterlist *)schp->buffer;
res = st_map_user_pages(sgl, mx_sc_elems, (unsigned long)hp->dxferp, dxfer_len,
(SG_DXFER_TO_DEV == hp->dxfer_direction) ? 1 : 0, ULONG_MAX);
if (res <= 0)
return 1;
schp->k_use_sg = res;
schp->dio_in_use = 1;
hp->info |= SG_INFO_DIRECT_IO;
return 0;
#else
return 1;
#endif
}
static int
sg_build_indirect(Sg_scatter_hold * schp, Sg_fd * sfp, int buff_size)
{
int ret_sz;
int blk_size = buff_size;
unsigned char *p = NULL;
if ((blk_size < 0) || (!sfp))
return -EFAULT;
if (0 == blk_size)
++blk_size; /* don't know why */
/* round request up to next highest SG_SECTOR_SZ byte boundary */
blk_size = (blk_size + SG_SECTOR_MSK) & (~SG_SECTOR_MSK);
SCSI_LOG_TIMEOUT(4, printk("sg_build_indirect: buff_size=%d, blk_size=%d\n",
buff_size, blk_size));
if (blk_size <= SG_SCATTER_SZ) {
p = sg_page_malloc(blk_size, sfp->low_dma, &ret_sz);
if (!p)
return -ENOMEM;
if (blk_size == ret_sz) { /* got it on the first attempt */
schp->k_use_sg = 0;
schp->buffer = p;
schp->bufflen = blk_size;
schp->b_malloc_len = blk_size;
return 0;
}
} else {
p = sg_page_malloc(SG_SCATTER_SZ, sfp->low_dma, &ret_sz);
if (!p)
return -ENOMEM;
}
/* Want some local declarations, so start new block ... */
{ /* lets try and build a scatter gather list */
struct scatterlist *sclp;
int k, rem_sz, num;
int mx_sc_elems;
int sg_tablesize = sfp->parentdp->sg_tablesize;
int first = 1;
/* N.B. ret_sz carried into this block ... */
mx_sc_elems = sg_build_sgat(schp, sfp, sg_tablesize);
if (mx_sc_elems < 0)
return mx_sc_elems; /* most likely -ENOMEM */
for (k = 0, sclp = schp->buffer, rem_sz = blk_size;
(rem_sz > 0) && (k < mx_sc_elems);
++k, rem_sz -= ret_sz, ++sclp) {
if (first)
first = 0;
else {
num =
(rem_sz >
SG_SCATTER_SZ) ? SG_SCATTER_SZ : rem_sz;
p = sg_page_malloc(num, sfp->low_dma, &ret_sz);
if (!p)
break;
}
sclp->page = virt_to_page(p);
sclp->offset = (unsigned long) p & ~PAGE_MASK;
sclp->length = ret_sz;
SCSI_LOG_TIMEOUT(5, printk("sg_build_build: k=%d, a=0x%p, len=%d\n",
k, sg_scatg2virt(sclp), ret_sz));
} /* end of for loop */
schp->k_use_sg = k;
SCSI_LOG_TIMEOUT(5, printk("sg_build_indirect: k_use_sg=%d, rem_sz=%d\n", k, rem_sz));
schp->bufflen = blk_size;
if (rem_sz > 0) /* must have failed */
return -ENOMEM;
}
return 0;
}
static int
sg_write_xfer(Sg_request * srp)
{
sg_io_hdr_t *hp = &srp->header;
Sg_scatter_hold *schp = &srp->data;
int num_xfer = 0;
int j, k, onum, usglen, ksglen, res;
int iovec_count = (int) hp->iovec_count;
int dxfer_dir = hp->dxfer_direction;
unsigned char *p;
unsigned char *up;
int new_interface = ('\0' == hp->interface_id) ? 0 : 1;
if ((SG_DXFER_UNKNOWN == dxfer_dir) || (SG_DXFER_TO_DEV == dxfer_dir) ||
(SG_DXFER_TO_FROM_DEV == dxfer_dir)) {
num_xfer = (int) (new_interface ? hp->dxfer_len : hp->flags);
if (schp->bufflen < num_xfer)
num_xfer = schp->bufflen;
}
if ((num_xfer <= 0) || (schp->dio_in_use) ||
(new_interface
&& ((SG_FLAG_NO_DXFER | SG_FLAG_MMAP_IO) & hp->flags)))
return 0;
SCSI_LOG_TIMEOUT(4, printk("sg_write_xfer: num_xfer=%d, iovec_count=%d, k_use_sg=%d\n",
num_xfer, iovec_count, schp->k_use_sg));
if (iovec_count) {
onum = iovec_count;
if ((k = verify_area(VERIFY_READ, hp->dxferp,
SZ_SG_IOVEC * onum)))
return k;
} else
onum = 1;
if (0 == schp->k_use_sg) { /* kernel has single buffer */
for (j = 0, p = schp->buffer; j < onum; ++j) {
res = sg_u_iovec(hp, iovec_count, j, 1, &usglen, &up);
if (res)
return res;
usglen = (num_xfer > usglen) ? usglen : num_xfer;
if (__copy_from_user(p, up, usglen))
return -EFAULT;
p += usglen;
num_xfer -= usglen;
if (num_xfer <= 0)
return 0;
}
} else { /* kernel using scatter gather list */
struct scatterlist *sclp = (struct scatterlist *) schp->buffer;
ksglen = (int) sclp->length;
p = sg_scatg2virt(sclp);
for (j = 0, k = 0; j < onum; ++j) {
res = sg_u_iovec(hp, iovec_count, j, 1, &usglen, &up);
if (res)
return res;
for (; k < schp->k_use_sg; ++k, ++sclp) {
ksglen = (int) sclp->length;
p = sg_scatg2virt(sclp);
if (NULL == p)
break;
if (usglen <= 0)
break;
if (ksglen > usglen) {
if (usglen >= num_xfer) {
if (__copy_from_user
(p, up, num_xfer))
return -EFAULT;
return 0;
}
if (__copy_from_user(p, up, usglen))
return -EFAULT;
p += usglen;
ksglen -= usglen;
break;
} else {
if (ksglen >= num_xfer) {
if (__copy_from_user
(p, up, num_xfer))
return -EFAULT;
return 0;
}
if (__copy_from_user(p, up, ksglen))
return -EFAULT;
up += ksglen;
usglen -= ksglen;
}
}
}
}
return 0;
}
static int
sg_u_iovec(sg_io_hdr_t * hp, int sg_num, int ind,
int wr_xf, int *countp, unsigned char **up)
{
int num_xfer = (int) hp->dxfer_len;
unsigned char *p;
int count, k;
sg_iovec_t u_iovec;
if (0 == sg_num) {
p = (unsigned char *) hp->dxferp;
if (wr_xf && ('\0' == hp->interface_id))
count = (int) hp->flags; /* holds "old" input_size */
else
count = num_xfer;
} else {
if (__copy_from_user(&u_iovec,
(unsigned char *) hp->dxferp +
(ind * SZ_SG_IOVEC), SZ_SG_IOVEC))
return -EFAULT;
p = (unsigned char *) u_iovec.iov_base;
count = (int) u_iovec.iov_len;
}
if ((k = verify_area(wr_xf ? VERIFY_READ : VERIFY_WRITE, p, count)))
return k;
if (up)
*up = p;
if (countp)
*countp = count;
return 0;
}
static void
sg_remove_scat(Sg_scatter_hold * schp)
{
SCSI_LOG_TIMEOUT(4, printk("sg_remove_scat: k_use_sg=%d\n", schp->k_use_sg));
if (schp->buffer && (schp->sglist_len > 0)) {
struct scatterlist *sclp = (struct scatterlist *) schp->buffer;
if (schp->dio_in_use) {
#ifdef SG_ALLOW_DIO_CODE
st_unmap_user_pages(sclp, schp->k_use_sg, TRUE);
#endif
} else {
int k;
for (k = 0; (k < schp->k_use_sg) && sg_scatg2virt(sclp);
++k, ++sclp) {
SCSI_LOG_TIMEOUT(5, printk(
"sg_remove_scat: k=%d, a=0x%p, len=%d\n",
k, sg_scatg2virt(sclp), sclp->length));
sg_page_free(sg_scatg2virt(sclp), sclp->length);
sclp->page = NULL;
sclp->offset = 0;
sclp->length = 0;
}
}
sg_page_free(schp->buffer, schp->sglist_len);
} else if (schp->buffer)
sg_page_free(schp->buffer, schp->b_malloc_len);
memset(schp, 0, sizeof (*schp));
}
static int
sg_read_xfer(Sg_request * srp)
{
sg_io_hdr_t *hp = &srp->header;
Sg_scatter_hold *schp = &srp->data;
int num_xfer = 0;
int j, k, onum, usglen, ksglen, res;
int iovec_count = (int) hp->iovec_count;
int dxfer_dir = hp->dxfer_direction;
unsigned char *p;
unsigned char *up;
int new_interface = ('\0' == hp->interface_id) ? 0 : 1;
if ((SG_DXFER_UNKNOWN == dxfer_dir) || (SG_DXFER_FROM_DEV == dxfer_dir)
|| (SG_DXFER_TO_FROM_DEV == dxfer_dir)) {
num_xfer = hp->dxfer_len;
if (schp->bufflen < num_xfer)
num_xfer = schp->bufflen;
}
if ((num_xfer <= 0) || (schp->dio_in_use) ||
(new_interface
&& ((SG_FLAG_NO_DXFER | SG_FLAG_MMAP_IO) & hp->flags)))
return 0;
SCSI_LOG_TIMEOUT(4, printk("sg_read_xfer: num_xfer=%d, iovec_count=%d, k_use_sg=%d\n",
num_xfer, iovec_count, schp->k_use_sg));
if (iovec_count) {
onum = iovec_count;
if ((k = verify_area(VERIFY_READ, hp->dxferp,
SZ_SG_IOVEC * onum)))
return k;
} else
onum = 1;
if (0 == schp->k_use_sg) { /* kernel has single buffer */
for (j = 0, p = schp->buffer; j < onum; ++j) {
res = sg_u_iovec(hp, iovec_count, j, 0, &usglen, &up);
if (res)
return res;
usglen = (num_xfer > usglen) ? usglen : num_xfer;
if (__copy_to_user(up, p, usglen))
return -EFAULT;
p += usglen;
num_xfer -= usglen;
if (num_xfer <= 0)
return 0;
}
} else { /* kernel using scatter gather list */
struct scatterlist *sclp = (struct scatterlist *) schp->buffer;
ksglen = (int) sclp->length;
p = sg_scatg2virt(sclp);
for (j = 0, k = 0; j < onum; ++j) {
res = sg_u_iovec(hp, iovec_count, j, 0, &usglen, &up);
if (res)
return res;
for (; k < schp->k_use_sg; ++k, ++sclp) {
ksglen = (int) sclp->length;
p = sg_scatg2virt(sclp);
if (NULL == p)
break;
if (usglen <= 0)
break;
if (ksglen > usglen) {
if (usglen >= num_xfer) {
if (__copy_to_user
(up, p, num_xfer))
return -EFAULT;
return 0;
}
if (__copy_to_user(up, p, usglen))
return -EFAULT;
p += usglen;
ksglen -= usglen;
break;
} else {
if (ksglen >= num_xfer) {
if (__copy_to_user
(up, p, num_xfer))
return -EFAULT;
return 0;
}
if (__copy_to_user(up, p, ksglen))
return -EFAULT;
up += ksglen;
usglen -= ksglen;
}
}
}
}
return 0;
}
static int
sg_read_oxfer(Sg_request * srp, char *outp, int num_read_xfer)
{
Sg_scatter_hold *schp = &srp->data;
SCSI_LOG_TIMEOUT(4, printk("sg_read_oxfer: num_read_xfer=%d\n",
num_read_xfer));
if ((!outp) || (num_read_xfer <= 0))
return 0;
if (schp->k_use_sg > 0) {
int k, num;
struct scatterlist *sclp = (struct scatterlist *) schp->buffer;
for (k = 0; (k < schp->k_use_sg) && sg_scatg2virt(sclp);
++k, ++sclp) {
num = (int) sclp->length;
if (num > num_read_xfer) {
if (__copy_to_user
(outp, sg_scatg2virt(sclp), num_read_xfer))
return -EFAULT;
break;
} else {
if (__copy_to_user
(outp, sg_scatg2virt(sclp), num))
return -EFAULT;
num_read_xfer -= num;
if (num_read_xfer <= 0)
break;
outp += num;
}
}
} else {
if (__copy_to_user(outp, schp->buffer, num_read_xfer))
return -EFAULT;
}
return 0;
}
static void
sg_build_reserve(Sg_fd * sfp, int req_size)
{
Sg_scatter_hold *schp = &sfp->reserve;
SCSI_LOG_TIMEOUT(4, printk("sg_build_reserve: req_size=%d\n", req_size));
do {
if (req_size < PAGE_SIZE)
req_size = PAGE_SIZE;
if (0 == sg_build_indirect(schp, sfp, req_size))
return;
else
sg_remove_scat(schp);
req_size >>= 1; /* divide by 2 */
} while (req_size > (PAGE_SIZE / 2));
}
static void
sg_link_reserve(Sg_fd * sfp, Sg_request * srp, int size)
{
Sg_scatter_hold *req_schp = &srp->data;
Sg_scatter_hold *rsv_schp = &sfp->reserve;
srp->res_used = 1;
SCSI_LOG_TIMEOUT(4, printk("sg_link_reserve: size=%d\n", size));
size = (size + 1) & (~1); /* round to even for aha1542 */
if (rsv_schp->k_use_sg > 0) {
int k, num;
int rem = size;
struct scatterlist *sclp =
(struct scatterlist *) rsv_schp->buffer;
for (k = 0; k < rsv_schp->k_use_sg; ++k, ++sclp) {
num = (int) sclp->length;
if (rem <= num) {
if (0 == k) {
req_schp->k_use_sg = 0;
req_schp->buffer = sg_scatg2virt(sclp);
} else {
sfp->save_scat_len = num;
sclp->length = (unsigned) rem;
req_schp->k_use_sg = k + 1;
req_schp->sglist_len =
rsv_schp->sglist_len;
req_schp->buffer = rsv_schp->buffer;
}
req_schp->bufflen = size;
req_schp->b_malloc_len = rsv_schp->b_malloc_len;
break;
} else
rem -= num;
}
if (k >= rsv_schp->k_use_sg)
SCSI_LOG_TIMEOUT(1, printk("sg_link_reserve: BAD size\n"));
} else {
req_schp->k_use_sg = 0;
req_schp->bufflen = size;
req_schp->buffer = rsv_schp->buffer;
req_schp->b_malloc_len = rsv_schp->b_malloc_len;
}
}
static void
sg_unlink_reserve(Sg_fd * sfp, Sg_request * srp)
{
Sg_scatter_hold *req_schp = &srp->data;
Sg_scatter_hold *rsv_schp = &sfp->reserve;
SCSI_LOG_TIMEOUT(4, printk("sg_unlink_reserve: req->k_use_sg=%d\n",
(int) req_schp->k_use_sg));
if ((rsv_schp->k_use_sg > 0) && (req_schp->k_use_sg > 0)) {
struct scatterlist *sclp =
(struct scatterlist *) rsv_schp->buffer;
if (sfp->save_scat_len > 0)
(sclp + (req_schp->k_use_sg - 1))->length =
(unsigned) sfp->save_scat_len;
else
SCSI_LOG_TIMEOUT(1, printk ("sg_unlink_reserve: BAD save_scat_len\n"));
}
req_schp->k_use_sg = 0;
req_schp->bufflen = 0;
req_schp->buffer = NULL;
req_schp->sglist_len = 0;
sfp->save_scat_len = 0;
srp->res_used = 0;
}
static Sg_request *
sg_get_rq_mark(Sg_fd * sfp, int pack_id)
{
Sg_request *resp;
unsigned long iflags;
write_lock_irqsave(&sfp->rq_list_lock, iflags);
for (resp = sfp->headrp; resp; resp = resp->nextrp) {
/* look for requests that are ready + not SG_IO owned */
if ((1 == resp->done) && (!resp->sg_io_owned) &&
((-1 == pack_id) || (resp->header.pack_id == pack_id))) {
resp->done = 2; /* guard against other readers */
break;
}
}
write_unlock_irqrestore(&sfp->rq_list_lock, iflags);
return resp;
}
#ifdef CONFIG_PROC_FS
static Sg_request *
sg_get_nth_request(Sg_fd * sfp, int nth)
{
Sg_request *resp;
unsigned long iflags;
int k;
read_lock_irqsave(&sfp->rq_list_lock, iflags);
for (k = 0, resp = sfp->headrp; resp && (k < nth);
++k, resp = resp->nextrp) ;
read_unlock_irqrestore(&sfp->rq_list_lock, iflags);
return resp;
}
#endif
/* always adds to end of list */
static Sg_request *
sg_add_request(Sg_fd * sfp)
{
int k;
unsigned long iflags;
Sg_request *resp;
Sg_request *rp = sfp->req_arr;
write_lock_irqsave(&sfp->rq_list_lock, iflags);
resp = sfp->headrp;
if (!resp) {
memset(rp, 0, sizeof (Sg_request));
rp->parentfp = sfp;
resp = rp;
sfp->headrp = resp;
} else {
if (0 == sfp->cmd_q)
resp = NULL; /* command queuing disallowed */
else {
for (k = 0; k < SG_MAX_QUEUE; ++k, ++rp) {
if (!rp->parentfp)
break;
}
if (k < SG_MAX_QUEUE) {
memset(rp, 0, sizeof (Sg_request));
rp->parentfp = sfp;
while (resp->nextrp)
resp = resp->nextrp;
resp->nextrp = rp;
resp = rp;
} else
resp = NULL;
}
}
if (resp) {
resp->nextrp = NULL;
resp->header.duration = jiffies;
resp->my_cmdp = NULL;
}
write_unlock_irqrestore(&sfp->rq_list_lock, iflags);
return resp;
}
/* Return of 1 for found; 0 for not found */
static int
sg_remove_request(Sg_fd * sfp, Sg_request * srp)
{
Sg_request *prev_rp;
Sg_request *rp;
unsigned long iflags;
int res = 0;
if ((!sfp) || (!srp) || (!sfp->headrp))
return res;
write_lock_irqsave(&sfp->rq_list_lock, iflags);
prev_rp = sfp->headrp;
if (srp == prev_rp) {
sfp->headrp = prev_rp->nextrp;
prev_rp->parentfp = NULL;
res = 1;
} else {
while ((rp = prev_rp->nextrp)) {
if (srp == rp) {
prev_rp->nextrp = rp->nextrp;
rp->parentfp = NULL;
res = 1;
break;
}
prev_rp = rp;
}
}
write_unlock_irqrestore(&sfp->rq_list_lock, iflags);
return res;
}
#ifdef CONFIG_PROC_FS
static Sg_fd *
sg_get_nth_sfp(Sg_device * sdp, int nth)
{
Sg_fd *resp;
unsigned long iflags;
int k;
read_lock_irqsave(&sg_dev_arr_lock, iflags);
for (k = 0, resp = sdp->headfp; resp && (k < nth);
++k, resp = resp->nextfp) ;
read_unlock_irqrestore(&sg_dev_arr_lock, iflags);
return resp;
}
#endif
static Sg_fd *
sg_add_sfp(Sg_device * sdp, int dev)
{
Sg_fd *sfp;
unsigned long iflags;
sfp = (Sg_fd *) sg_page_malloc(sizeof (Sg_fd), 0, 0);
if (!sfp)
return NULL;
memset(sfp, 0, sizeof (Sg_fd));
init_waitqueue_head(&sfp->read_wait);
sfp->rq_list_lock = RW_LOCK_UNLOCKED;
sfp->timeout = SG_DEFAULT_TIMEOUT;
sfp->timeout_user = SG_DEFAULT_TIMEOUT_USER;
sfp->force_packid = SG_DEF_FORCE_PACK_ID;
sfp->low_dma = (SG_DEF_FORCE_LOW_DMA == 0) ?
sdp->device->host->unchecked_isa_dma : 1;
sfp->cmd_q = SG_DEF_COMMAND_Q;
sfp->keep_orphan = SG_DEF_KEEP_ORPHAN;
sfp->parentdp = sdp;
write_lock_irqsave(&sg_dev_arr_lock, iflags);
if (!sdp->headfp)
sdp->headfp = sfp;