Commit 906d15fb authored by Christoph Hellwig's avatar Christoph Hellwig
Browse files

scsi: split scsi_nonblockable_ioctl 



The calling conventions for this function are bad as it could return
-ENODEV both for a device not currently online and a not recognized ioctl.

Add a new scsi_ioctl_block_when_processing_errors function that wraps
scsi_block_when_processing_errors with the a special case for the
SG_SCSI_RESET ioctl command, and handle the SG_SCSI_RESET case itself
in scsi_ioctl.  All callers of scsi_ioctl now must call the above helper
to check for the EH state, so that the ioctl handler itself doesn't
have to.

Reported-by: default avatarRobert Elliott <Elliott@hp.com>
Signed-off-by: default avatarChristoph Hellwig <hch@lst.de>
Reviewed-by: default avatarMartin K. Petersen <martin.petersen@oracle.com>
Reviewed-by: default avatarHannes Reinecke <hare@suse.de>
parent 176aa9d6

drivers/scsi/ch.c

+5 −0
Original line number Diff line number Diff line
@@ -616,6 +616,11 @@ static long ch_ioctl(struct file *file, 
	int retval;

	void __user *argp = (void __user *)arg;



	retval = scsi_ioctl_block_when_processing_errors(ch->device, cmd,

			file->f_flags & O_NDELAY);

	if (retval)

		return retval;



	switch (cmd) {

	case CHIOGPARAMS:

	{

drivers/scsi/osst.c

+3 −3
Original line number Diff line number Diff line
@@ -4969,10 +4969,10 @@ static long osst_ioctl(struct file * file, 
	 * may try and take the device offline, in which case all further

	 * access to the device is prohibited.

	 */

	if( !scsi_block_when_processing_errors(STp->device) ) {

		retval = (-ENXIO);

	retval = scsi_ioctl_block_when_processing_errors(STp->device, cmd_in,

			file->f_flags & O_NDELAY);

	if (retval)

		goto out;

	}



	cmd_type = _IOC_TYPE(cmd_in);

	cmd_nr   = _IOC_NR(cmd_in);

drivers/scsi/scsi_ioctl.c

+13 −34
Original line number Diff line number Diff line
@@ -200,19 +200,6 @@ 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) {
@@ -273,6 +260,8 @@ int scsi_ioctl(struct scsi_device *sdev, int cmd, void __user *arg) 
				     START_STOP_TIMEOUT, NORMAL_RETRIES);

        case SCSI_IOCTL_GET_PCI:

                return scsi_ioctl_get_pci(sdev, arg);

	case SG_SCSI_RESET:

		return scsi_ioctl_reset(sdev, arg);

	default:

		if (sdev->host->hostt->ioctl)

			return sdev->host->hostt->ioctl(sdev, cmd, arg);
@@ -281,30 +270,20 @@ int scsi_ioctl(struct scsi_device *sdev, int cmd, void __user *arg) 
}

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,TARGET,BUS,HOST}

 *       possibly OR-ed with SG_SCSI_RESET_NO_ESCALATE

 * @ndelay: file mode O_NDELAY flag

/*

 * We can process a reset even when a device isn't fully operable.

 */

int scsi_nonblockable_ioctl(struct scsi_device *sdev, int cmd,

			    void __user *arg, int ndelay)

int scsi_ioctl_block_when_processing_errors(struct scsi_device *sdev, int cmd,

		bool ndelay)

{

	/* 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 (cmd == SG_SCSI_RESET && ndelay) {

		if (scsi_host_in_recovery(sdev->host))

			return -ENODEV;

	} else if (!scsi_block_when_processing_errors(sdev))

	} else {

		if (!scsi_block_when_processing_errors(sdev))

			return -ENODEV;



	switch (cmd) {

	case SG_SCSI_RESET:

		return scsi_ioctl_reset(sdev, arg);

	}

	return -ENODEV;



	return 0;

}

EXPORT_SYMBOL(scsi_nonblockable_ioctl);
 
EXPORT_SYMBOL_GPL(scsi_ioctl_block_when_processing_errors);

drivers/scsi/sd.c

+3 −3
Original line number Diff line number Diff line
@@ -1334,9 +1334,9 @@ static int sd_ioctl(struct block_device *bdev, fmode_t mode, 
	 * may try and take the device offline, in which case all further

	 * access to the device is prohibited.

	 */

	error = scsi_nonblockable_ioctl(sdp, cmd, p,

	error = scsi_ioctl_block_when_processing_errors(sdp, cmd,

			(mode & FMODE_NDELAY) != 0);

	if (!scsi_block_when_processing_errors(sdp) || !error)

	if (error)

		goto out;



	/*

drivers/scsi/sg.c

+15 −18
Original line number Diff line number Diff line
@@ -1071,16 +1071,6 @@ sg_ioctl(struct file *filp, unsigned int cmd_in, unsigned long arg) 
		if (atomic_read(&sdp->detaching))

			return -ENODEV;

		return put_user(sdp->device->host->hostt->emulated, ip);

	case SG_SCSI_RESET:

		if (atomic_read(&sdp->detaching))

			return -ENODEV;

		if (filp->f_flags & O_NONBLOCK) {

			if (scsi_host_in_recovery(sdp->device->host))

				return -EBUSY;

		} else if (!scsi_block_when_processing_errors(sdp->device))

			return -EBUSY;



		return scsi_ioctl_reset(sdp->device, ip);

	case SCSI_IOCTL_SEND_COMMAND:

		if (atomic_read(&sdp->detaching))

			return -ENODEV;
@@ -1100,13 +1090,6 @@ sg_ioctl(struct file *filp, unsigned int cmd_in, unsigned long arg) 
			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 (atomic_read(&sdp->detaching))

			return -ENODEV;

		return scsi_ioctl(sdp->device, cmd_in, p);

	case BLKSECTGET:

		return put_user(max_sectors_bytes(sdp->device->request_queue),

				ip);
@@ -1122,11 +1105,25 @@ sg_ioctl(struct file *filp, unsigned int cmd_in, unsigned long arg) 
		return blk_trace_startstop(sdp->device->request_queue, 0);

	case BLKTRACETEARDOWN:

		return blk_trace_remove(sdp->device->request_queue);

	case SCSI_IOCTL_GET_IDLUN:

	case SCSI_IOCTL_GET_BUS_NUMBER:

	case SCSI_IOCTL_PROBE_HOST:

	case SG_GET_TRANSFORM:

	case SG_SCSI_RESET:

		if (atomic_read(&sdp->detaching))

			return -ENODEV;

		break;

	default:

		if (read_only)

			return -EPERM;	/* don't know so take safe approach */

		return scsi_ioctl(sdp->device, cmd_in, p);

		break;

	}



	result = scsi_ioctl_block_when_processing_errors(sdp->device,

			cmd_in, filp->f_flags & O_NDELAY);

	if (result)

		return result;

	return scsi_ioctl(sdp->device, cmd_in, p);

}



#ifdef CONFIG_COMPAT

CRA Git | Maintained and supported by SUSTech CRA and CCSE