ide-scsi.c

linux 内核源代码

	} else {
		pc->scsi_cmd->result = DID_OK << 16;
	}
	host = pc->scsi_cmd->device->host;
	spin_lock_irqsave(host->host_lock, flags);
	pc->done(pc->scsi_cmd);
	spin_unlock_irqrestore(host->host_lock, flags);
	kfree(pc);
	kfree(rq);
	scsi->pc = NULL;
	return 0;
}

static inline unsigned long get_timeout(idescsi_pc_t *pc)
{
	return max_t(unsigned long, WAIT_CMD, pc->timeout - jiffies);
}

static int idescsi_expiry(ide_drive_t *drive)
{
	idescsi_scsi_t *scsi = drive_to_idescsi(drive);
	idescsi_pc_t   *pc   = scsi->pc;

#if IDESCSI_DEBUG_LOG
	printk(KERN_WARNING "idescsi_expiry called for %lu at %lu\n", pc->scsi_cmd->serial_number, jiffies);
#endif
	set_bit(PC_TIMEDOUT, &pc->flags);

	return 0;					/* we do not want the ide subsystem to retry */
}

/*
 *	Our interrupt handler.
 */
static ide_startstop_t idescsi_pc_intr (ide_drive_t *drive)
{
	idescsi_scsi_t *scsi = drive_to_idescsi(drive);
	idescsi_pc_t *pc=scsi->pc;
	struct request *rq = pc->rq;
	atapi_bcount_t bcount;
	atapi_status_t status;
	atapi_ireason_t ireason;
	atapi_feature_t feature;

	unsigned int temp;

#if IDESCSI_DEBUG_LOG
	printk (KERN_INFO "ide-scsi: Reached idescsi_pc_intr interrupt handler\n");
#endif /* IDESCSI_DEBUG_LOG */

	if (test_bit(PC_TIMEDOUT, &pc->flags)){
#if IDESCSI_DEBUG_LOG
		printk(KERN_WARNING "idescsi_pc_intr: got timed out packet  %lu at %lu\n",
				pc->scsi_cmd->serial_number, jiffies);
#endif
		/* end this request now - scsi should retry it*/
		idescsi_end_request (drive, 1, 0);
		return ide_stopped;
	}
	if (test_and_clear_bit (PC_DMA_IN_PROGRESS, &pc->flags)) {
#if IDESCSI_DEBUG_LOG
		printk ("ide-scsi: %s: DMA complete\n", drive->name);
#endif /* IDESCSI_DEBUG_LOG */
		pc->actually_transferred=pc->request_transfer;
		(void) HWIF(drive)->ide_dma_end(drive);
	}

	feature.all = 0;
	/* Clear the interrupt */
	status.all = HWIF(drive)->INB(IDE_STATUS_REG);

	if (!status.b.drq) {
		/* No more interrupts */
		if (test_bit(IDESCSI_LOG_CMD, &scsi->log))
			printk (KERN_INFO "Packet command completed, %d bytes transferred\n", pc->actually_transferred);
		local_irq_enable_in_hardirq();
		if (status.b.check)
			rq->errors++;
		idescsi_end_request (drive, 1, 0);
		return ide_stopped;
	}
	bcount.b.low	= HWIF(drive)->INB(IDE_BCOUNTL_REG);
	bcount.b.high	= HWIF(drive)->INB(IDE_BCOUNTH_REG);
	ireason.all	= HWIF(drive)->INB(IDE_IREASON_REG);

	if (ireason.b.cod) {
		printk(KERN_ERR "ide-scsi: CoD != 0 in idescsi_pc_intr\n");
		return ide_do_reset (drive);
	}
	if (ireason.b.io) {
		temp = pc->actually_transferred + bcount.all;
		if (temp > pc->request_transfer) {
			if (temp > pc->buffer_size) {
				printk(KERN_ERR "ide-scsi: The scsi wants to "
					"send us more data than expected "
					"- discarding data\n");
				temp = pc->buffer_size - pc->actually_transferred;
				if (temp) {
					clear_bit(PC_WRITING, &pc->flags);
					if (pc->sg)
						idescsi_input_buffers(drive, pc, temp);
					else
						drive->hwif->atapi_input_bytes(drive, pc->current_position, temp);
					printk(KERN_ERR "ide-scsi: transferred %d of %d bytes\n", temp, bcount.all);
				}
				pc->actually_transferred += temp;
				pc->current_position += temp;
				idescsi_discard_data(drive, bcount.all - temp);
				ide_set_handler(drive, &idescsi_pc_intr, get_timeout(pc), idescsi_expiry);
				return ide_started;
			}
#if IDESCSI_DEBUG_LOG
			printk (KERN_NOTICE "ide-scsi: The scsi wants to send us more data than expected - allowing transfer\n");
#endif /* IDESCSI_DEBUG_LOG */
		}
	}
	if (ireason.b.io) {
		clear_bit(PC_WRITING, &pc->flags);
		if (pc->sg)
			idescsi_input_buffers(drive, pc, bcount.all);
		else
			HWIF(drive)->atapi_input_bytes(drive, pc->current_position, bcount.all);
	} else {
		set_bit(PC_WRITING, &pc->flags);
		if (pc->sg)
			idescsi_output_buffers (drive, pc, bcount.all);
		else
			HWIF(drive)->atapi_output_bytes(drive, pc->current_position, bcount.all);
	}
	/* Update the current position */
	pc->actually_transferred += bcount.all;
	pc->current_position += bcount.all;

	/* And set the interrupt handler again */
	ide_set_handler(drive, &idescsi_pc_intr, get_timeout(pc), idescsi_expiry);
	return ide_started;
}

static ide_startstop_t idescsi_transfer_pc(ide_drive_t *drive)
{
	ide_hwif_t *hwif = drive->hwif;
	idescsi_scsi_t *scsi = drive_to_idescsi(drive);
	idescsi_pc_t *pc = scsi->pc;
	atapi_ireason_t ireason;
	ide_startstop_t startstop;

	if (ide_wait_stat(&startstop,drive,DRQ_STAT,BUSY_STAT,WAIT_READY)) {
		printk(KERN_ERR "ide-scsi: Strange, packet command "
			"initiated yet DRQ isn't asserted\n");
		return startstop;
	}
	ireason.all	= HWIF(drive)->INB(IDE_IREASON_REG);
	if (!ireason.b.cod || ireason.b.io) {
		printk(KERN_ERR "ide-scsi: (IO,CoD) != (0,1) while "
				"issuing a packet command\n");
		return ide_do_reset (drive);
	}
	BUG_ON(HWGROUP(drive)->handler != NULL);
	/* Set the interrupt routine */
	ide_set_handler(drive, &idescsi_pc_intr, get_timeout(pc), idescsi_expiry);
	/* Send the actual packet */
	drive->hwif->atapi_output_bytes(drive, scsi->pc->c, 12);
	if (test_bit (PC_DMA_OK, &pc->flags)) {
		set_bit (PC_DMA_IN_PROGRESS, &pc->flags);
		hwif->dma_start(drive);
	}
	return ide_started;
}

static inline int idescsi_set_direction(idescsi_pc_t *pc)
{
	switch (pc->c[0]) {
		case READ_6: case READ_10: case READ_12:
			clear_bit(PC_WRITING, &pc->flags);
			return 0;
		case WRITE_6: case WRITE_10: case WRITE_12:
			set_bit(PC_WRITING, &pc->flags);
			return 0;
		default:
			return 1;
	}
}

static int idescsi_map_sg(ide_drive_t *drive, idescsi_pc_t *pc)
{
	ide_hwif_t *hwif = drive->hwif;
	struct scatterlist *sg, *scsi_sg;
	int segments;

	if (!pc->request_transfer || pc->request_transfer % 1024)
		return 1;

	if (idescsi_set_direction(pc))
		return 1;

	sg = hwif->sg_table;
	scsi_sg = scsi_sglist(pc->scsi_cmd);
	segments = scsi_sg_count(pc->scsi_cmd);

	if (segments > hwif->sg_max_nents)
		return 1;

	hwif->sg_nents = segments;
	memcpy(sg, scsi_sg, sizeof(*sg) * segments);

	return 0;
}

/*
 *	Issue a packet command
 */
static ide_startstop_t idescsi_issue_pc (ide_drive_t *drive, idescsi_pc_t *pc)
{
	idescsi_scsi_t *scsi = drive_to_idescsi(drive);
	ide_hwif_t *hwif = drive->hwif;
	atapi_feature_t feature;
	atapi_bcount_t bcount;

	scsi->pc=pc;							/* Set the current packet command */
	pc->actually_transferred=0;					/* We haven't transferred any data yet */
	pc->current_position=pc->buffer;
	bcount.all = min(pc->request_transfer, 63 * 1024);		/* Request to transfer the entire buffer at once */

	feature.all = 0;
	if (drive->using_dma && !idescsi_map_sg(drive, pc)) {
		hwif->sg_mapped = 1;
		feature.b.dma = !hwif->dma_setup(drive);
		hwif->sg_mapped = 0;
	}

	SELECT_DRIVE(drive);
	if (IDE_CONTROL_REG)
		HWIF(drive)->OUTB(drive->ctl, IDE_CONTROL_REG);

	HWIF(drive)->OUTB(feature.all, IDE_FEATURE_REG);
	HWIF(drive)->OUTB(bcount.b.high, IDE_BCOUNTH_REG);
	HWIF(drive)->OUTB(bcount.b.low, IDE_BCOUNTL_REG);

	if (feature.b.dma)
		set_bit(PC_DMA_OK, &pc->flags);

	if (test_bit(IDESCSI_DRQ_INTERRUPT, &scsi->flags)) {
		BUG_ON(HWGROUP(drive)->handler != NULL);
		ide_set_handler(drive, &idescsi_transfer_pc,
				get_timeout(pc), idescsi_expiry);
		/* Issue the packet command */
		HWIF(drive)->OUTB(WIN_PACKETCMD, IDE_COMMAND_REG);
		return ide_started;
	} else {
		/* Issue the packet command */
		HWIF(drive)->OUTB(WIN_PACKETCMD, IDE_COMMAND_REG);
		return idescsi_transfer_pc(drive);
	}
}

/*
 *	idescsi_do_request is our request handling function.
 */
static ide_startstop_t idescsi_do_request (ide_drive_t *drive, struct request *rq, sector_t block)
{
#if IDESCSI_DEBUG_LOG
	printk (KERN_INFO "dev: %s, cmd: %x, errors: %d\n", rq->rq_disk->disk_name,rq->cmd[0],rq->errors);
	printk (KERN_INFO "sector: %ld, nr_sectors: %ld, current_nr_sectors: %d\n",rq->sector,rq->nr_sectors,rq->current_nr_sectors);
#endif /* IDESCSI_DEBUG_LOG */

	if (blk_sense_request(rq) || blk_special_request(rq)) {
		return idescsi_issue_pc (drive, (idescsi_pc_t *) rq->special);
	}
	blk_dump_rq_flags(rq, "ide-scsi: unsup command");
	idescsi_end_request (drive, 0, 0);
	return ide_stopped;
}

#ifdef CONFIG_IDE_PROC_FS
static void idescsi_add_settings(ide_drive_t *drive)
{
	idescsi_scsi_t *scsi = drive_to_idescsi(drive);

/*
 *			drive	setting name	read/write	data type	min	max	mul_factor	div_factor	data pointer		set function
 */
	ide_add_setting(drive,	"bios_cyl",	SETTING_RW,	TYPE_INT,	0,	1023,	1,		1,		&drive->bios_cyl,	NULL);
	ide_add_setting(drive,	"bios_head",	SETTING_RW,	TYPE_BYTE,	0,	255,	1,		1,		&drive->bios_head,	NULL);
	ide_add_setting(drive,	"bios_sect",	SETTING_RW,	TYPE_BYTE,	0,	63,	1,		1,		&drive->bios_sect,	NULL);
	ide_add_setting(drive,	"transform",	SETTING_RW,	TYPE_INT,	0,	3,	1,		1,		&scsi->transform,	NULL);
	ide_add_setting(drive,	"log",		SETTING_RW,	TYPE_INT,	0,	1,	1,		1,		&scsi->log,		NULL);
}
#else
static inline void idescsi_add_settings(ide_drive_t *drive) { ; }
#endif

/*
 *	Driver initialization.
 */
static void idescsi_setup (ide_drive_t *drive, idescsi_scsi_t *scsi)
{
	if (drive->id && (drive->id->config & 0x0060) == 0x20)
		set_bit (IDESCSI_DRQ_INTERRUPT, &scsi->flags);
	clear_bit(IDESCSI_SG_TRANSFORM, &scsi->transform);
#if IDESCSI_DEBUG_LOG
	set_bit(IDESCSI_LOG_CMD, &scsi->log);
#endif /* IDESCSI_DEBUG_LOG */
	idescsi_add_settings(drive);
}

static void ide_scsi_remove(ide_drive_t *drive)
{
	struct Scsi_Host *scsihost = drive->driver_data;
	struct ide_scsi_obj *scsi = scsihost_to_idescsi(scsihost);
	struct gendisk *g = scsi->disk;

	scsi_remove_host(scsihost);
	ide_proc_unregister_driver(drive, scsi->driver);

	ide_unregister_region(g);

	drive->driver_data = NULL;
	g->private_data = NULL;
	put_disk(g);

	ide_scsi_put(scsi);
}

static int ide_scsi_probe(ide_drive_t *);

#ifdef CONFIG_IDE_PROC_FS
static ide_proc_entry_t idescsi_proc[] = {
	{ "capacity", S_IFREG|S_IRUGO, proc_ide_read_capacity, NULL },
	{ NULL, 0, NULL, NULL }
};
#endif

static ide_driver_t idescsi_driver = {
	.gen_driver = {
		.owner		= THIS_MODULE,
		.name		= "ide-scsi",
		.bus		= &ide_bus_type,
	},
	.probe			= ide_scsi_probe,
	.remove			= ide_scsi_remove,
	.version		= IDESCSI_VERSION,
	.media			= ide_scsi,
	.supports_dsc_overlap	= 0,
	.do_request		= idescsi_do_request,
	.end_request		= idescsi_end_request,
	.error                  = idescsi_atapi_error,
	.abort                  = idescsi_atapi_abort,
#ifdef CONFIG_IDE_PROC_FS
	.proc			= idescsi_proc,
#endif
};

static int idescsi_ide_open(struct inode *inode, struct file *filp)
{
	struct gendisk *disk = inode->i_bdev->bd_disk;
	struct ide_scsi_obj *scsi;

	if (!(scsi = ide_scsi_get(disk)))
		return -ENXIO;