- 根目录:
- drivers
- scsi
- scsi_ioctl.c
/*
* Changes:
* Arnaldo Carvalho de Melo <acme@conectiva.com.br> 08/23/2000
* - get rid of some verify_areas and use __copy*user and __get/put_user
* for the ones that remain
*/
#include <linux/module.h>
#include <linux/blkdev.h>
#include <linux/interrupt.h>
#include <linux/errno.h>
#include <linux/kernel.h>
#include <linux/sched.h>
#include <linux/mm.h>
#include <linux/string.h>
#include <asm/uaccess.h>
#include <scsi/scsi.h>
#include <scsi/scsi_cmnd.h>
#include <scsi/scsi_device.h>
#include <scsi/scsi_eh.h>
#include <scsi/scsi_host.h>
#include <scsi/scsi_ioctl.h>
#include <scsi/sg.h>
#include <scsi/scsi_dbg.h>
#include "scsi_logging.h"
#define NORMAL_RETRIES 5
#define IOCTL_NORMAL_TIMEOUT (10 * HZ)
#define MAX_BUF PAGE_SIZE
/**
* ioctl_probe -- return host identification
* @host: host to identify
* @buffer: userspace buffer for identification
*
* Return an identifying string at @buffer, if @buffer is non-NULL, filling
* to the length stored at * (int *) @buffer.
*/
static int ioctl_probe(struct Scsi_Host *host, void __user *buffer)
{
unsigned int len, slen;
const char *string;
if (buffer) {
if (get_user(len, (unsigned int __user *) buffer))
return -EFAULT;
if (host->hostt->info)
string = host->hostt->info(host);
else
string = host->hostt->name;
if (string) {
slen = strlen(string);
if (len > slen)
len = slen + 1;
if (copy_to_user(buffer, string, len))
return -EFAULT;
}
}
return 1;
}
/*
* The SCSI_IOCTL_SEND_COMMAND ioctl sends a command out to the SCSI host.
* The IOCTL_NORMAL_TIMEOUT and NORMAL_RETRIES variables are used.
*
* dev is the SCSI device struct ptr, *(int *) arg is the length of the
* input data, if any, not including the command string & counts,
* *((int *)arg + 1) is the output buffer size in bytes.
*
* *(char *) ((int *) arg)[2] the actual command byte.
*
* Note that if more than MAX_BUF bytes are requested to be transferred,
* the ioctl will fail with error EINVAL.
*
* This size *does not* include the initial lengths that were passed.
*
* The SCSI command is read from the memory location immediately after the
* length words, and the input data is right after the command. The SCSI
* routines know the command size based on the opcode decode.
*
* The output area is then filled in starting from the command byte.
*/
static int ioctl_internal_command(struct scsi_device *sdev, char *cmd,
int timeout, int retries)
{
int result;
struct scsi_sense_hdr sshdr;
SCSI_LOG_IOCTL(1, printk("Trying ioctl with scsi command %d\n", *cmd));
result = scsi_execute_req(sdev, cmd, DMA_NONE, NULL, 0,
&sshdr, timeout, retries, NULL);
SCSI_LOG_IOCTL(2, printk("Ioctl returned 0x%x\n", result));
if ((driver_byte(result) & DRIVER_SENSE) &&
(scsi_sense_valid(&sshdr))) {
switch (sshdr.sense_key) {
case ILLEGAL_REQUEST:
if (cmd[0] == ALLOW_MEDIUM_REMOVAL)
sdev->lockable = 0;
else
printk(KERN_INFO "ioctl_internal_command: "
"ILLEGAL REQUEST asc=0x%x ascq=0x%x\n",
sshdr.asc, sshdr.ascq);
break;
case NOT_READY: /* This happens if there is no disc in drive */
if (sdev->removable)
break;
case UNIT_ATTENTION:
if (sdev->removable) {
sdev->changed = 1;
result = 0; /* This is no longer considered an error */
break;
}
default: /* Fall through for non-removable media */
sdev_printk(KERN_INFO, sdev,
"ioctl_internal_command return code = %x\n",
result);
scsi_print_sense_hdr(" ", &sshdr);
break;
}
}
SCSI_LOG_IOCTL(2, printk("IOCTL Releasing command\n"));
return result;
}
int scsi_set_medium_removal(struct scsi_device *sdev, char state)
{
char scsi_cmd[MAX_COMMAND_SIZE];
int ret;
if (!sdev->removable || !sdev->lockable)
return 0;
scsi_cmd[0] = ALLOW_MEDIUM_REMOVAL;
scsi_cmd[1] = 0;
scsi_cmd[2] = 0;
scsi_cmd[3] = 0;
scsi_cmd[4] = state;
scsi_cmd[5] = 0;
ret = ioctl_internal_command(sdev, scsi_cmd,
IOCTL_NORMAL_TIMEOUT, NORMAL_RETRIES);
if (ret == 0)
sdev->locked = (state == SCSI_REMOVAL_PREVENT);
return ret;
}
EXPORT_SYMBOL(scsi_set_medium_removal);
/*
* The scsi_ioctl_get_pci() function places into arg the value
* pci_dev::slot_name (8 characters) for the PCI device (if any).
* Returns: 0 on success
* -ENXIO if there isn't a PCI device pointer
* (could be because the SCSI driver hasn't been
* updated yet, or because it isn't a SCSI
* device)
* any copy_to_user() error on failure there
*/
static int scsi_ioctl_get_pci(struct scsi_device *sdev, void __user *arg)
{
struct device *dev = scsi_get_device(sdev->host);
const char *name;
if (!dev)
return -ENXIO;
name = dev_name(dev);
/* compatibility with old ioctl which only returned
* 20 characters */
return copy_to_user(arg, name, min(strlen(name), (size_t)20))
? -EFAULT: 0;
}
/**
* scsi_ioctl - Dispatch ioctl to scsi device
* @sdev: scsi device receiving ioctl
* @cmd: which ioctl is it
* @arg: data associated with ioctl
*
* Description: The scsi_ioctl() function differs from most ioctls in that it
* does not take a major/minor number as the dev field. Rather, it takes
* a pointer to a &struct scsi_device.
*/
int scsi_ioctl(struct scsi_device *sdev, int cmd, void __user *arg)
{
char scsi_cmd[MAX_COMMAND_SIZE];
/* No idea how this happens.... */
if (!sdev)
return -ENXIO;
/*
* If we are in the middle of error recovery, don't let anyone
* else try and use this device. Also, if error recovery fails, it
* may try and take the device offline, in which case all further
* access to the device is prohibited.
*/
if (!scsi_block_when_processing_errors(sdev))
return -ENODEV;
/* Check for deprecated ioctls ... all the ioctls which don't
* follow the new unique numbering scheme are deprecated */
switch (cmd) {
case SCSI_IOCTL_SEND_COMMAND:
case SCSI_IOCTL_TEST_UNIT_READY:
case SCSI_IOCTL_BENCHMARK_COMMAND:
case SCSI_IOCTL_SYNC:
case SCSI_IOCTL_START_UNIT:
case SCSI_IOCTL_STOP_UNIT:
printk(KERN_WARNING "program %s is using a deprecated SCSI "
"ioctl, please convert it to SG_IO\n", current->comm);
break;
default:
break;
}
switch (cmd) {
case SCSI_IOCTL_GET_IDLUN:
if (!access_ok(VERIFY_WRITE, arg, sizeof(struct scsi_idlun)))
return -EFAULT;
__put_user((sdev->id & 0xff)
+ ((sdev->lun & 0xff) << 8)
+ ((sdev->channel & 0xff) << 16)
+ ((sdev->host->host_no & 0xff) << 24),
&((struct scsi_idlun __user *)arg)->dev_id);
__put_user(sdev->host->unique_id,
&((struct scsi_idlun __user *)arg)->host_unique_id);
return 0;
case SCSI_IOCTL_GET_BUS_NUMBER:
return put_user(sdev->host->host_no, (int __user *)arg);
case SCSI_IOCTL_PROBE_HOST:
return ioctl_probe(sdev->host, arg);
case SCSI_IOCTL_SEND_COMMAND:
if (!capable(CAP_SYS_ADMIN) || !capable(CAP_SYS_RAWIO))
return -EACCES;
return sg_scsi_ioctl(sdev->request_queue, NULL, 0, arg);
case SCSI_IOCTL_DOORLOCK:
return scsi_set_medium_removal(sdev, SCSI_REMOVAL_PREVENT);
case SCSI_IOCTL_DOORUNLOCK:
return scsi_set_medium_removal(sdev, SCSI_REMOVAL_ALLOW);
case SCSI_IOCTL_TEST_UNIT_READY:
return scsi_test_unit_ready(sdev, IOCTL_NORMAL_TIMEOUT,
NORMAL_RETRIES, NULL);
case SCSI_IOCTL_START_UNIT:
scsi_cmd[0] = START_STOP;
scsi_cmd[1] = 0;
scsi_cmd[2] = scsi_cmd[3] = scsi_cmd[5] = 0;
scsi_cmd[4] = 1;
return ioctl_internal_command(sdev, scsi_cmd,
START_STOP_TIMEOUT, NORMAL_RETRIES);
case SCSI_IOCTL_STOP_UNIT:
scsi_cmd[0] = START_STOP;
scsi_cmd[1] = 0;
scsi_cmd[2] = scsi_cmd[3] = scsi_cmd[5] = 0;
scsi_cmd[4] = 0;
return ioctl_internal_command(sdev, scsi_cmd,
START_STOP_TIMEOUT, NORMAL_RETRIES);
case SCSI_IOCTL_GET_PCI:
return scsi_ioctl_get_pci(sdev, arg);
default:
if (sdev->host->hostt->ioctl)
return sdev->host->hostt->ioctl(sdev, cmd, arg);
}
return -EINVAL;
}
EXPORT_SYMBOL(scsi_ioctl);
/**
* scsi_nonblockable_ioctl() - Handle SG_SCSI_RESET
* @sdev: scsi device receiving ioctl
* @cmd: Must be SC_SCSI_RESET
* @arg: pointer to int containing SG_SCSI_RESET_{DEVICE,BUS,HOST}
* @ndelay: file mode O_NDELAY flag
*/
int scsi_nonblockable_ioctl(struct scsi_device *sdev, int cmd,
void __user *arg, int ndelay)
{
int val, result;
/* The first set of iocts may be executed even if we're doing
* error processing, as long as the device was opened
* non-blocking */
if (ndelay) {
if (scsi_host_in_recovery(sdev->host))
return -ENODEV;
} else if (!scsi_block_when_processing_errors(sdev))
return -ENODEV;
switch (cmd) {
case SG_SCSI_RESET:
result = get_user(val, (int __user *)arg);
if (result)
return result;
if (val == SG_SCSI_RESET_NOTHING)
return 0;
switch (val) {
case SG_SCSI_RESET_DEVICE:
val = SCSI_TRY_RESET_DEVICE;
break;
case SG_SCSI_RESET_TARGET:
val = SCSI_TRY_RESET_TARGET;
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(sdev, val) ==
SUCCESS) ? 0 : -EIO;
}
return -ENODEV;
}
EXPORT_SYMBOL(scsi_nonblockable_ioctl);