ide-io.c

linux 内核源代码

		if (err == ABRT_ERR) {
			if (drive->select.b.lba &&
			    /* some newer drives don't support WIN_SPECIFY */
			    hwif->INB(IDE_COMMAND_REG) == WIN_SPECIFY)
				return ide_stopped;
		} else if ((err & BAD_CRC) == BAD_CRC) {
			/* UDMA crc error, just retry the operation */
			drive->crc_count++;
		} else if (err & (BBD_ERR | ECC_ERR)) {
			/* retries won't help these */
			rq->errors = ERROR_MAX;
		} else if (err & TRK0_ERR) {
			/* help it find track zero */
			rq->errors |= ERROR_RECAL;
		}
	}

	if ((stat & DRQ_STAT) && rq_data_dir(rq) == READ &&
	    (hwif->host_flags & IDE_HFLAG_ERROR_STOPS_FIFO) == 0)
		try_to_flush_leftover_data(drive);

	if (rq->errors >= ERROR_MAX || blk_noretry_request(rq)) {
		ide_kill_rq(drive, rq);
		return ide_stopped;
	}

	if (hwif->INB(IDE_STATUS_REG) & (BUSY_STAT|DRQ_STAT))
		rq->errors |= ERROR_RESET;

	if ((rq->errors & ERROR_RESET) == ERROR_RESET) {
		++rq->errors;
		return ide_do_reset(drive);
	}

	if ((rq->errors & ERROR_RECAL) == ERROR_RECAL)
		drive->special.b.recalibrate = 1;

	++rq->errors;

	return ide_stopped;
}

static ide_startstop_t ide_atapi_error(ide_drive_t *drive, struct request *rq, u8 stat, u8 err)
{
	ide_hwif_t *hwif = drive->hwif;

	if (stat & BUSY_STAT || ((stat & WRERR_STAT) && !drive->nowerr)) {
		/* other bits are useless when BUSY */
		rq->errors |= ERROR_RESET;
	} else {
		/* add decoding error stuff */
	}

	if (hwif->INB(IDE_STATUS_REG) & (BUSY_STAT|DRQ_STAT))
		/* force an abort */
		hwif->OUTB(WIN_IDLEIMMEDIATE, IDE_COMMAND_REG);

	if (rq->errors >= ERROR_MAX) {
		ide_kill_rq(drive, rq);
	} else {
		if ((rq->errors & ERROR_RESET) == ERROR_RESET) {
			++rq->errors;
			return ide_do_reset(drive);
		}
		++rq->errors;
	}

	return ide_stopped;
}

ide_startstop_t
__ide_error(ide_drive_t *drive, struct request *rq, u8 stat, u8 err)
{
	if (drive->media == ide_disk)
		return ide_ata_error(drive, rq, stat, err);
	return ide_atapi_error(drive, rq, stat, err);
}

EXPORT_SYMBOL_GPL(__ide_error);

/**
 *	ide_error	-	handle an error on the IDE
 *	@drive: drive the error occurred on
 *	@msg: message to report
 *	@stat: status bits
 *
 *	ide_error() takes action based on the error returned by the drive.
 *	For normal I/O that may well include retries. We deal with
 *	both new-style (taskfile) and old style command handling here.
 *	In the case of taskfile command handling there is work left to
 *	do
 */
 
ide_startstop_t ide_error (ide_drive_t *drive, const char *msg, u8 stat)
{
	struct request *rq;
	u8 err;

	err = ide_dump_status(drive, msg, stat);

	if ((rq = HWGROUP(drive)->rq) == NULL)
		return ide_stopped;

	/* retry only "normal" I/O: */
	if (!blk_fs_request(rq)) {
		rq->errors = 1;
		ide_end_drive_cmd(drive, stat, err);
		return ide_stopped;
	}

	if (rq->rq_disk) {
		ide_driver_t *drv;

		drv = *(ide_driver_t **)rq->rq_disk->private_data;
		return drv->error(drive, rq, stat, err);
	} else
		return __ide_error(drive, rq, stat, err);
}

EXPORT_SYMBOL_GPL(ide_error);

ide_startstop_t __ide_abort(ide_drive_t *drive, struct request *rq)
{
	if (drive->media != ide_disk)
		rq->errors |= ERROR_RESET;

	ide_kill_rq(drive, rq);

	return ide_stopped;
}

EXPORT_SYMBOL_GPL(__ide_abort);

/**
 *	ide_abort	-	abort pending IDE operations
 *	@drive: drive the error occurred on
 *	@msg: message to report
 *
 *	ide_abort kills and cleans up when we are about to do a 
 *	host initiated reset on active commands. Longer term we
 *	want handlers to have sensible abort handling themselves
 *
 *	This differs fundamentally from ide_error because in 
 *	this case the command is doing just fine when we
 *	blow it away.
 */
 
ide_startstop_t ide_abort(ide_drive_t *drive, const char *msg)
{
	struct request *rq;

	if (drive == NULL || (rq = HWGROUP(drive)->rq) == NULL)
		return ide_stopped;

	/* retry only "normal" I/O: */
	if (!blk_fs_request(rq)) {
		rq->errors = 1;
		ide_end_drive_cmd(drive, BUSY_STAT, 0);
		return ide_stopped;
	}

	if (rq->rq_disk) {
		ide_driver_t *drv;

		drv = *(ide_driver_t **)rq->rq_disk->private_data;
		return drv->abort(drive, rq);
	} else
		return __ide_abort(drive, rq);
}

/**
 *	ide_cmd		-	issue a simple drive command
 *	@drive: drive the command is for
 *	@cmd: command byte
 *	@nsect: sector byte
 *	@handler: handler for the command completion
 *
 *	Issue a simple drive command with interrupts.
 *	The drive must be selected beforehand.
 */

static void ide_cmd (ide_drive_t *drive, u8 cmd, u8 nsect,
		ide_handler_t *handler)
{
	ide_hwif_t *hwif = HWIF(drive);
	if (IDE_CONTROL_REG)
		hwif->OUTB(drive->ctl,IDE_CONTROL_REG);	/* clear nIEN */
	SELECT_MASK(drive,0);
	hwif->OUTB(nsect,IDE_NSECTOR_REG);
	ide_execute_command(drive, cmd, handler, WAIT_CMD, NULL);
}

/**
 *	drive_cmd_intr		- 	drive command completion interrupt
 *	@drive: drive the completion interrupt occurred on
 *
 *	drive_cmd_intr() is invoked on completion of a special DRIVE_CMD.
 *	We do any necessary data reading and then wait for the drive to
 *	go non busy. At that point we may read the error data and complete
 *	the request
 */
 
static ide_startstop_t drive_cmd_intr (ide_drive_t *drive)
{
	struct request *rq = HWGROUP(drive)->rq;
	ide_hwif_t *hwif = HWIF(drive);
	u8 *args = (u8 *) rq->buffer;
	u8 stat = hwif->INB(IDE_STATUS_REG);
	int retries = 10;

	local_irq_enable_in_hardirq();
	if (rq->cmd_type == REQ_TYPE_ATA_CMD &&
	    (stat & DRQ_STAT) && args && args[3]) {
		u8 io_32bit = drive->io_32bit;
		drive->io_32bit = 0;
		hwif->ata_input_data(drive, &args[4], args[3] * SECTOR_WORDS);
		drive->io_32bit = io_32bit;
		while (((stat = hwif->INB(IDE_STATUS_REG)) & BUSY_STAT) && retries--)
			udelay(100);
	}

	if (!OK_STAT(stat, READY_STAT, BAD_STAT))
		return ide_error(drive, "drive_cmd", stat);
		/* calls ide_end_drive_cmd */
	ide_end_drive_cmd(drive, stat, hwif->INB(IDE_ERROR_REG));
	return ide_stopped;
}

static void ide_init_specify_cmd(ide_drive_t *drive, ide_task_t *task)
{
	task->tfRegister[IDE_NSECTOR_OFFSET] = drive->sect;
	task->tfRegister[IDE_SECTOR_OFFSET]  = drive->sect;
	task->tfRegister[IDE_LCYL_OFFSET]    = drive->cyl;
	task->tfRegister[IDE_HCYL_OFFSET]    = drive->cyl>>8;
	task->tfRegister[IDE_SELECT_OFFSET]  = ((drive->head-1)|drive->select.all)&0xBF;
	task->tfRegister[IDE_COMMAND_OFFSET] = WIN_SPECIFY;

	task->handler = &set_geometry_intr;
}

static void ide_init_restore_cmd(ide_drive_t *drive, ide_task_t *task)
{
	task->tfRegister[IDE_NSECTOR_OFFSET] = drive->sect;
	task->tfRegister[IDE_COMMAND_OFFSET] = WIN_RESTORE;

	task->handler = &recal_intr;
}

static void ide_init_setmult_cmd(ide_drive_t *drive, ide_task_t *task)
{
	task->tfRegister[IDE_NSECTOR_OFFSET] = drive->mult_req;
	task->tfRegister[IDE_COMMAND_OFFSET] = WIN_SETMULT;

	task->handler = &set_multmode_intr;
}

static ide_startstop_t ide_disk_special(ide_drive_t *drive)
{
	special_t *s = &drive->special;
	ide_task_t args;

	memset(&args, 0, sizeof(ide_task_t));
	args.command_type = IDE_DRIVE_TASK_NO_DATA;

	if (s->b.set_geometry) {
		s->b.set_geometry = 0;
		ide_init_specify_cmd(drive, &args);
	} else if (s->b.recalibrate) {
		s->b.recalibrate = 0;
		ide_init_restore_cmd(drive, &args);
	} else if (s->b.set_multmode) {
		s->b.set_multmode = 0;
		if (drive->mult_req > drive->id->max_multsect)
			drive->mult_req = drive->id->max_multsect;
		ide_init_setmult_cmd(drive, &args);
	} else if (s->all) {
		int special = s->all;
		s->all = 0;
		printk(KERN_ERR "%s: bad special flag: 0x%02x\n", drive->name, special);
		return ide_stopped;
	}

	do_rw_taskfile(drive, &args);

	return ide_started;
}

/*
 * handle HDIO_SET_PIO_MODE ioctl abusers here, eventually it will go away
 */
static int set_pio_mode_abuse(ide_hwif_t *hwif, u8 req_pio)
{
	switch (req_pio) {
	case 202:
	case 201:
	case 200:
	case 102:
	case 101:
	case 100:
		return (hwif->host_flags & IDE_HFLAG_ABUSE_DMA_MODES) ? 1 : 0;
	case 9:
	case 8:
		return (hwif->host_flags & IDE_HFLAG_ABUSE_PREFETCH) ? 1 : 0;
	case 7:
	case 6:
		return (hwif->host_flags & IDE_HFLAG_ABUSE_FAST_DEVSEL) ? 1 : 0;
	default:
		return 0;
	}
}

/**
 *	do_special		-	issue some special commands
 *	@drive: drive the command is for
 *
 *	do_special() is used to issue WIN_SPECIFY, WIN_RESTORE, and WIN_SETMULT
 *	commands to a drive.  It used to do much more, but has been scaled
 *	back.
 */

static ide_startstop_t do_special (ide_drive_t *drive)
{
	special_t *s = &drive->special;

#ifdef DEBUG
	printk("%s: do_special: 0x%02x\n", drive->name, s->all);
#endif
	if (s->b.set_tune) {
		ide_hwif_t *hwif = drive->hwif;
		u8 req_pio = drive->tune_req;

		s->b.set_tune = 0;

		if (set_pio_mode_abuse(drive->hwif, req_pio)) {

			if (hwif->set_pio_mode == NULL)
				return ide_stopped;

			/*
			 * take ide_lock for drive->[no_]unmask/[no_]io_32bit
			 */
			if (req_pio == 8 || req_pio == 9) {
				unsigned long flags;

				spin_lock_irqsave(&ide_lock, flags);
				hwif->set_pio_mode(drive, req_pio);
				spin_unlock_irqrestore(&ide_lock, flags);
			} else
				hwif->set_pio_mode(drive, req_pio);
		} else {
			int keep_dma = drive->using_dma;

			ide_set_pio(drive, req_pio);

			if (hwif->host_flags & IDE_HFLAG_SET_PIO_MODE_KEEP_DMA) {
				if (keep_dma)
					hwif->ide_dma_on(drive);
			}
		}

		return ide_stopped;
	} else {
		if (drive->media == ide_disk)
			return ide_disk_special(drive);

		s->all = 0;
		drive->mult_req = 0;
		return ide_stopped;
	}
}

void ide_map_sg(ide_drive_t *drive, struct request *rq)
{
	ide_hwif_t *hwif = drive->hwif;
	struct scatterlist *sg = hwif->sg_table;

	if (hwif->sg_mapped)	/* needed by ide-scsi */
		return;

	if (rq->cmd_type != REQ_TYPE_ATA_TASKFILE) {
		hwif->sg_nents = blk_rq_map_sg(drive->queue, rq, sg);
	} else {
		sg_init_one(sg, rq->buffer, rq->nr_sectors * SECTOR_SIZE);
		hwif->sg_nents = 1;
	}
}

EXPORT_SYMBOL_GPL(ide_map_sg);

void ide_init_sg_cmd(ide_drive_t *drive, struct request *rq)
{
	ide_hwif_t *hwif = drive->hwif;

	hwif->nsect = hwif->nleft = rq->nr_sectors;
	hwif->cursg_ofs = 0;
	hwif->cursg = NULL;
}

EXPORT_SYMBOL_GPL(ide_init_sg_cmd);

/**
 *	execute_drive_command	-	issue special drive command
 *	@drive: the drive to issue the command on
 *	@rq: the request structure holding the command
 *
 *	execute_drive_cmd() issues a special drive command,  usually 
 *	initiated by ioctl() from the external hdparm program. The
 *	command can be a drive command, drive task or taskfile 
 *	operation. Weirdly you can call it with NULL to wait for
 *	all commands to finish. Don't do this as that is due to change
 */

static ide_startstop_t execute_drive_cmd (ide_drive_t *drive,
		struct request *rq)
{
	ide_hwif_t *hwif = HWIF(drive);
	if (rq->cmd_type == REQ_TYPE_ATA_TASKFILE) {
 		ide_task_t *args = rq->special;
 
		if (!args)
			goto done;

		hwif->data_phase = args->data_phase;

		switch (hwif->data_phase) {
		case TASKFILE_MULTI_OUT:
		case TASKFILE_OUT:
		case TASKFILE_MULTI_IN:
		case TASKFILE_IN:
			ide_init_sg_cmd(drive, rq);
			ide_map_sg(drive, rq);
		default:
			break;
		}

		if (args->tf_out_flags.all != 0) 
			return flagged_taskfile(drive, args);
		return do_rw_taskfile(drive, args);
	} else if (rq->cmd_type == REQ_TYPE_ATA_TASK) {
		u8 *args = rq->buffer;
 
		if (!args)
			goto done;
#ifdef DEBUG
 		printk("%s: DRIVE_TASK_CMD ", drive->name);
 		printk("cmd=0x%02x ", args[0]);
 		printk("fr=0x%02x ", args[1]);