Commit 5a5dbd18 authored by Mark Lord's avatar Mark Lord Committed by Jeff Garzik
Browse files

libata: add support for READ/WRITE LONG 



The READ/WRITE LONG commands are theoretically obsolete,
but the majority of drives in existance still implement them.

The WRITE_LONG and WRITE_LONG_ONCE commands are of particular
interest for fault injection testing -- eg. creating "media errors"
at specific locations on a disk.

The fussy bit is that these commands require a non-standard
sector size, usually 520 bytes instead of 512.

This patch adds support to libata for READ/WRITE LONG commands
issued via SG_IO/ATA_16.

Signed-off-by: default avatarMark Lord <mlord@pobox.com>
Signed-off-by: default avatarJeff Garzik <jeff@garzik.org>
parent 12340106

drivers/ata/libata-core.c

+10 −10
Original line number Diff line number Diff line
@@ -4106,10 +4106,10 @@ void ata_data_xfer_noirq(struct ata_device *adev, unsigned char *buf, 




/**

 *	ata_pio_sector - Transfer ATA_SECT_SIZE (512 bytes) of data.

 *	ata_pio_sector - Transfer a sector of data.

 *	@qc: Command on going

 *

 *	Transfer ATA_SECT_SIZE of data from/to the ATA device.

 *	Transfer qc->sect_size bytes of data from/to the ATA device.

 *

 *	LOCKING:

 *	Inherited from caller.
@@ -4124,7 +4124,7 @@ static void ata_pio_sector(struct ata_queued_cmd *qc) 
	unsigned int offset;

	unsigned char *buf;



	if (qc->curbytes == qc->nbytes - ATA_SECT_SIZE)

	if (qc->curbytes == qc->nbytes - qc->sect_size)

		ap->hsm_task_state = HSM_ST_LAST;



	page = sg[qc->cursg].page;
@@ -4144,17 +4144,17 @@ static void ata_pio_sector(struct ata_queued_cmd *qc) 
		buf = kmap_atomic(page, KM_IRQ0);



		/* do the actual data transfer */

		ap->ops->data_xfer(qc->dev, buf + offset, ATA_SECT_SIZE, do_write);

		ap->ops->data_xfer(qc->dev, buf + offset, qc->sect_size, do_write);



		kunmap_atomic(buf, KM_IRQ0);

		local_irq_restore(flags);

	} else {

		buf = page_address(page);

		ap->ops->data_xfer(qc->dev, buf + offset, ATA_SECT_SIZE, do_write);

		ap->ops->data_xfer(qc->dev, buf + offset, qc->sect_size, do_write);

	}



	qc->curbytes += ATA_SECT_SIZE;

	qc->cursg_ofs += ATA_SECT_SIZE;

	qc->curbytes += qc->sect_size;

	qc->cursg_ofs += qc->sect_size;



	if (qc->cursg_ofs == (&sg[qc->cursg])->length) {

		qc->cursg++;
@@ -4163,10 +4163,10 @@ static void ata_pio_sector(struct ata_queued_cmd *qc) 
}



/**

 *	ata_pio_sectors - Transfer one or many 512-byte sectors.

 *	ata_pio_sectors - Transfer one or many sectors.

 *	@qc: Command on going

 *

 *	Transfer one or many ATA_SECT_SIZE of data from/to the

 *	Transfer one or many sectors of data from/to the

 *	ATA device for the DRQ request.

 *

 *	LOCKING:
@@ -4181,7 +4181,7 @@ static void ata_pio_sectors(struct ata_queued_cmd *qc) 


		WARN_ON(qc->dev->multi_count == 0);



		nsect = min((qc->nbytes - qc->curbytes) / ATA_SECT_SIZE,

		nsect = min((qc->nbytes - qc->curbytes) / qc->sect_size,

			    qc->dev->multi_count);

		while (nsect--)

			ata_pio_sector(qc);

drivers/ata/libata-scsi.c

+12 −0
Original line number Diff line number Diff line
@@ -2678,6 +2678,18 @@ static unsigned int ata_scsi_pass_thru(struct ata_queued_cmd *qc) 
		tf->device = qc->dev->devno ?

			tf->device | ATA_DEV1 : tf->device & ~ATA_DEV1;



	/* READ/WRITE LONG use a non-standard sect_size */

	qc->sect_size = ATA_SECT_SIZE;

	switch (tf->command) {

	case ATA_CMD_READ_LONG:

	case ATA_CMD_READ_LONG_ONCE:

	case ATA_CMD_WRITE_LONG:

	case ATA_CMD_WRITE_LONG_ONCE:

		if (tf->protocol != ATA_PROT_PIO || tf->nsect != 1)

			goto invalid_fld;

		qc->sect_size = scmd->request_bufflen;

	}



	/*

	 * Filter SET_FEATURES - XFER MODE command -- otherwise,

	 * SET_FEATURES - XFER MODE must be preceded/succeeded

include/linux/ata.h

+6 −0
Original line number Diff line number Diff line
@@ -164,6 +164,12 @@ enum { 
	/* READ_LOG_EXT pages */

	ATA_LOG_SATA_NCQ	= 0x10,



	/* READ/WRITE LONG (obsolete) */

	ATA_CMD_READ_LONG	= 0x22,

	ATA_CMD_READ_LONG_ONCE	= 0x23,

	ATA_CMD_WRITE_LONG	= 0x32,

	ATA_CMD_WRITE_LONG_ONCE	= 0x33,



	/* SETFEATURES stuff */

	SETFEATURES_XFER	= 0x03,

	XFER_UDMA_7		= 0x47,

include/linux/libata.h

+2 −0
Original line number Diff line number Diff line
@@ -427,6 +427,7 @@ struct ata_queued_cmd { 
	int			dma_dir;



	unsigned int		pad_len;

	unsigned int		sect_size;



	unsigned int		nbytes;

	unsigned int		curbytes;
@@ -1182,6 +1183,7 @@ static inline void ata_qc_reinit(struct ata_queued_cmd *qc) 
	qc->n_elem = 0;

	qc->err_mask = 0;

	qc->pad_len = 0;

	qc->sect_size = ATA_SECT_SIZE;



	ata_tf_init(qc->dev, &qc->tf);

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