acsi.c

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	if (DEVICE_INTR)
		return;

  repeat:
	CLEAR_TIMER();
	/* Another check here: An interrupt or timer event could have
	 * happened since the last check!
	 */
	if (!QUEUE_EMPTY && CURRENT->rq_status == RQ_INACTIVE) {
		if (!DEVICE_INTR) {
			ENABLE_IRQ();
			stdma_release();
		}
		return;
	}
	if (DEVICE_INTR)
		return;

	if (QUEUE_EMPTY) {
		CLEAR_INTR;
		ENABLE_IRQ();
		stdma_release();
		return;
	}
	
	if (MAJOR(CURRENT->rq_dev) != MAJOR_NR)
		panic(DEVICE_NAME ": request list destroyed");
	if (CURRENT->bh) {
		if (!CURRENT->bh && !buffer_locked(CURRENT->bh))
			panic(DEVICE_NAME ": block not locked");
	}

	dev = MINOR(CURRENT->rq_dev);
	block = CURRENT->sector;
	if (DEVICE_NR(dev) >= NDevices ||
		block+CURRENT->nr_sectors >= acsi_part[dev].nr_sects) {
#ifdef DEBUG
		printk( "ad%c: attempted access for blocks %d...%ld past end of device at block %ld.\n",
		       DEVICE_NR(dev)+'a',
		       block, block + CURRENT->nr_sectors - 1,
		       acsi_part[dev].nr_sects);
#endif
		end_request(0);
		goto repeat;
	}
	if (acsi_info[DEVICE_NR(dev)].changed) {
		printk( KERN_NOTICE "ad%c: request denied because cartridge has "
				"been changed.\n", DEVICE_NR(dev)+'a' );
		end_request(0);
		goto repeat;
	}
	
	block += acsi_part[dev].start_sect;
	target = acsi_info[DEVICE_NR(dev)].target;
	lun    = acsi_info[DEVICE_NR(dev)].lun;

	/* Find out how many sectors should be transferred from/to
	 * consecutive buffers and thus can be done with a single command.
	 */
	buffer      = CURRENT->buffer;
	pbuffer     = virt_to_phys(buffer);
	nsect       = CURRENT->current_nr_sectors;
	CurrentNReq = 1;

	if ((bh = CURRENT->bh) && bh != CURRENT->bhtail) {
		if (!STRAM_ADDR(pbuffer)) {
			/* If transfer is done via the ACSI buffer anyway, we can
			 * assemble as much bh's as fit in the buffer.
			 */
			while( (bh = bh->b_reqnext) ) {
				if (nsect + (bh->b_size>>9) > ACSI_BUFFER_SECTORS) break;
				nsect += bh->b_size >> 9;
				++CurrentNReq;
				if (bh == CURRENT->bhtail) break;
			}
			buffer = acsi_buffer;
			pbuffer = phys_acsi_buffer;
		}
		else {
			unsigned long pendadr, pnewadr;
			pendadr = pbuffer + nsect*512;
			while( (bh = bh->b_reqnext) ) {
				pnewadr = virt_to_phys(bh->b_data);
				if (!STRAM_ADDR(pnewadr) || pendadr != pnewadr) break;
				nsect += bh->b_size >> 9;
				pendadr = pnewadr + bh->b_size;
				++CurrentNReq;
				if (bh == CURRENT->bhtail) break;
			}
		}
	}
	else {
		if (!STRAM_ADDR(pbuffer)) {
			buffer = acsi_buffer;
			pbuffer = phys_acsi_buffer;
			if (nsect > ACSI_BUFFER_SECTORS)
				nsect = ACSI_BUFFER_SECTORS;
		}
	}
	CurrentBuffer = buffer;
	CurrentNSect  = nsect;
	
	if (CURRENT->cmd == WRITE) {
		CMDSET_TARG_LUN( write_cmd, target, lun );
		CMDSET_BLOCK( write_cmd, block );
		CMDSET_LEN( write_cmd, nsect );
		if (buffer == acsi_buffer)
			copy_to_acsibuffer();
		dma_cache_maintenance( pbuffer, nsect*512, 1 );
		SET_INTR(write_intr);
		if (!acsicmd_dma( write_cmd, buffer, nsect, 1, 1)) {
			CLEAR_INTR;
			printk( KERN_ERR "ACSI (write): Timeout in command block\n" );
			bad_rw_intr();
			goto repeat;
		}
		SET_TIMER();
		return;
	}
	if (CURRENT->cmd == READ) {
		CMDSET_TARG_LUN( read_cmd, target, lun );
		CMDSET_BLOCK( read_cmd, block );
		CMDSET_LEN( read_cmd, nsect );
		SET_INTR(read_intr);
		if (!acsicmd_dma( read_cmd, buffer, nsect, 0, 1)) {
			CLEAR_INTR;
			printk( KERN_ERR "ACSI (read): Timeout in command block\n" );
			bad_rw_intr();
			goto repeat;
		}
		SET_TIMER();
		return;
	}
	panic("unknown ACSI command");
}



/***********************************************************************
 *
 *  Misc functions: ioctl, open, release, check_change, ...
 *
 ***********************************************************************/


static int acsi_ioctl( struct inode *inode, struct file *file,
					   unsigned int cmd, unsigned long arg )
{	int dev;

	if (!inode)
		return -EINVAL;
	dev = DEVICE_NR(MINOR(inode->i_rdev));
	if (dev >= NDevices)
		return -EINVAL;
	switch (cmd) {
	  case HDIO_GETGEO:
		/* HDIO_GETGEO is supported more for getting the partition's
		 * start sector... */
	  { struct hd_geometry *geo = (struct hd_geometry *)arg;
	    /* just fake some geometry here, it's nonsense anyway; to make it
		 * easy, use Adaptec's usual 64/32 mapping */
	    put_user( 64, &geo->heads );
	    put_user( 32, &geo->sectors );
	    put_user( acsi_info[dev].size >> 11, &geo->cylinders );
		put_user( acsi_part[MINOR(inode->i_rdev)].start_sect, &geo->start );
		return 0;
	  }
		
	  case SCSI_IOCTL_GET_IDLUN:
		/* SCSI compatible GET_IDLUN call to get target's ID and LUN number */
		put_user( acsi_info[dev].target | (acsi_info[dev].lun << 8),
				  &((Scsi_Idlun *) arg)->dev_id );
		put_user( 0, &((Scsi_Idlun *) arg)->host_unique_id );
		return 0;
		
	  case BLKGETSIZE:   /* Return device size */
		return put_user(acsi_part[MINOR(inode->i_rdev)].nr_sects,
				(long *) arg);

	  case BLKROSET:
	  case BLKROGET:
	  case BLKFLSBUF:
	  case BLKPG:
		return blk_ioctl(inode->i_rdev, cmd, arg);

	  case BLKRRPART: /* Re-read partition tables */
	        if (!capable(CAP_SYS_ADMIN)) 
			return -EACCES;
		return revalidate_acsidisk(inode->i_rdev, 1);

	  default:
		return -EINVAL;
	}
}


/*
 * Open a device, check for read-only and lock the medium if it is
 * removable.
 *
 * Changes by Martin Rogge, 9th Aug 1995:
 * Check whether check_disk_change (and therefore revalidate_acsidisk)
 * was successful. They fail when there is no medium in the drive.
 *
 * The problem of media being changed during an operation can be 
 * ignored because of the prevent_removal code.
 *
 * Added check for the validity of the device number.
 *
 */

static int acsi_open( struct inode * inode, struct file * filp )
{
	int  device;
	struct acsi_info_struct *aip;

	device = DEVICE_NR(MINOR(inode->i_rdev));
	if (device >= NDevices)
		return -ENXIO;
	aip = &acsi_info[device];
	while (busy[device])
		sleep_on(&busy_wait);

	if (access_count[device] == 0 && aip->removable) {
#if 0
		aip->changed = 1;	/* safety first */
#endif
		check_disk_change( inode->i_rdev );
		if (aip->changed)	/* revalidate was not successful (no medium) */
			return -ENXIO;
		acsi_prevent_removal(device, 1);
	}
	access_count[device]++;
	MOD_INC_USE_COUNT;

	if (filp && filp->f_mode) {
		check_disk_change( inode->i_rdev );
		if (filp->f_mode & 2) {
			if (aip->read_only) {
				acsi_release( inode, filp );
				return -EROFS;
			}
		}
	}

	return 0;
}

/*
 * Releasing a block device means we sync() it, so that it can safely
 * be forgotten about...
 */

static int acsi_release( struct inode * inode, struct file * file )
{
	int device = DEVICE_NR(MINOR(inode->i_rdev));
	if (--access_count[device] == 0 && acsi_info[device].removable)
		acsi_prevent_removal(device, 0);
	MOD_DEC_USE_COUNT;
	return( 0 );
}

/*
 * Prevent or allow a media change for removable devices.
 */

static void acsi_prevent_removal(int device, int flag)
{
	stdma_lock( NULL, NULL );
	
	CMDSET_TARG_LUN(pa_med_rem_cmd, acsi_info[device].target,
			acsi_info[device].lun);
	CMDSET_LEN( pa_med_rem_cmd, flag );
	
	if (acsicmd_nodma(pa_med_rem_cmd, 0) && acsi_wait_for_IRQ(3*HZ))
		acsi_getstatus();
	/* Do not report errors -- some devices may not know this command. */

	ENABLE_IRQ();
	stdma_release();
}

static int acsi_media_change (dev_t dev)
{
	int device = DEVICE_NR(MINOR(dev));
	struct acsi_info_struct *aip;

	aip = &acsi_info[device];
	if (!aip->removable) 
		return 0;

	if (aip->changed)
		/* We can be sure that the medium has been changed -- REQUEST
		 * SENSE has reported this earlier.
		 */
		return 1;

	/* If the flag isn't set, make a test by reading block 0.
	 * If errors happen, it seems to be better to say "changed"...
	 */
	stdma_lock( NULL, NULL );
	CMDSET_TARG_LUN(read_cmd, aip->target, aip->lun);
	CMDSET_BLOCK( read_cmd, 0 );
	CMDSET_LEN( read_cmd, 1 );
	if (acsicmd_dma(read_cmd, acsi_buffer, 1, 0, 0) &&
	    acsi_wait_for_IRQ(3*HZ)) {
		if (acsi_getstatus()) {
			if (acsi_reqsense(acsi_buffer, aip->target, aip->lun)) {
				if (CARTRCH_STAT(device, acsi_buffer))
					aip->changed = 1;
			}
			else {
				printk( KERN_ERR "ad%c: REQUEST SENSE failed in test for "
				       "medium change; assuming a change\n", device + 'a' );
				aip->changed = 1;
			}
		}
	}
	else {
		printk( KERN_ERR "ad%c: Test for medium changed timed out; "
				"assuming a change\n", device + 'a');
		aip->changed = 1;
	}
	ENABLE_IRQ();
	stdma_release();

	/* Now, after reading a block, the changed status is surely valid. */
	return aip->changed;
}


static int acsi_change_blk_size( int target, int lun)

{	int i;

	for (i=0; i<12; i++)
		acsi_buffer[i] = 0;

	acsi_buffer[3] = 8;
	acsi_buffer[10] = 2;
	CMDSET_TARG_LUN( modeselect_cmd, target, lun);

	if (!acsicmd_dma( modeselect_cmd, acsi_buffer, 1,1,0) ||
		!acsi_wait_for_IRQ( 3*HZ ) ||
		acsi_getstatus() != 0 ) {
		return(0);
	}
	return(1);
}


static int acsi_mode_sense( int target, int lun, SENSE_DATA *sd )

{
	int page;

	CMDSET_TARG_LUN( modesense_cmd, target, lun );
	for (page=0; page<4; page++) {
		modesense_cmd[2] = page;
		if (!acsicmd_dma( modesense_cmd, acsi_buffer, 1, 0, 0 ) ||
		    !acsi_wait_for_IRQ( 3*HZ ) ||
		    acsi_getstatus())
			continue;

		/* read twice to jump over the second 16-byte border! */
		udelay(300);
		if (acsi_wait_for_noIRQ( 20 ) &&
		    acsicmd_nodma( modesense_cmd, 0 ) &&
		    acsi_wait_for_IRQ( 3*HZ ) &&
		    acsi_getstatus() == 0)
			break;
	}
	if (page == 4) {
		return(0);
	}

	dma_cache_maintenance( phys_acsi_buffer, sizeof(SENSE_DATA), 0 );
	*sd = *(SENSE_DATA *)acsi_buffer;

	/* Validity check, depending on type of data */
	
	switch( SENSE_TYPE(*sd) ) {

	  case SENSE_TYPE_ATARI:
		if (CAPACITY(*sd) == 0)
			goto invalid_sense;
		break;

	  case SENSE_TYPE_SCSI:
		if (sd->scsi.descriptor_size != 8)
			goto invalid_sense;
		break;

	  case SENSE_TYPE_UNKNOWN:

		printk( KERN_ERR "ACSI target %d, lun %d: Cannot interpret "
				"sense data\n", target, lun ); 
		
	  invalid_sense:

#ifdef DEBUG
		{	int i;
		printk( "Mode sense data for ACSI target %d, lun %d seem not valid:",
				target, lun );
		for( i = 0; i < sizeof(SENSE_DATA); ++i )
			printk( "%02x ", (unsigned char)acsi_buffer[i] );
		printk( "\n" );
		}
#endif
		return( 0 );
	}
		
	return( 1 );
}



/*******************************************************************
 *
 *  Initialization
 *
 ********************************************************************/


extern struct block_device_operations acsi_fops;

static struct gendisk acsi_gendisk = {
	MAJOR_NR,		/* Major number */	
	"ad",			/* Major name */
	4,			/* Bits to shift to get real from partition */
	1 << 4,			/* Number of partitions per real */
	acsi_part,		/* hd struct */
	acsi_sizes,		/* block sizes */
	0,			/* number */
	(void *)acsi_info,	/* internal */
	NULL,			/* next */
	&acsi_fops,		/* file operations */
};
	
#define MAX_SCSI_DEVICE_CODE 10

static const char *const scsi_device_types[MAX_SCSI_DEVICE_CODE] =
{
 "Direct-Access    ",
 "Sequential-Access",
 "Printer          ",
 "Processor        ",
 "WORM             ",
 "CD-ROM           ",
 "Scanner          ",
 "Optical Device   ",
 "Medium Changer   ",
 "Communications   "
};

static void print_inquiry(unsigned char *data)
{
	int i;

	printk(KERN_INFO "  Vendor: ");
	for (i = 8; i < 16; i++)
		{
	        if (data[i] >= 0x20 && i < data[4] + 5)
			printk("%c", data[i]);
		else
			printk(" ");
		}

	printk("  Model: ");
	for (i = 16; i < 32; i++)
		{
	        if (data[i] >= 0x20 && i < data[4] + 5)
			printk("%c", data[i]);
		else
			printk(" ");
		}

	printk("  Rev: ");
	for (i = 32; i < 36; i++)
		{
	        if (data[i] >= 0x20 && i < data[4] + 5)
			printk("%c", data[i]);