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libata: add support for READ/WRITE LONG commands

PATCH In review Mark Lord 1 participant 2 messages Feb 13, 2007 libata

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Mark Lord

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#0 lore raw

PATCH 1/1 libata: add support for READ/WRITE LONG commands

The READ/WRITE LONG commands are theoretically obsolete, but most (all?) drives to date still implement them.

Of these, WRITE_LONG and WRITE_LONG_ONCE 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.

---

drivers/ata/libata-core.c +0 -0
diff -u --recursive --new-file --exclude='.*' --exclude='*.[osa]' --exclude='*.ko' --exclude='*.mod.c' linux-2.6.20/drivers/ata/libata-core.c new/drivers/ata/libata-core.c
@@ -1249,7 +1249,7 @@
			buflen += sg[i].length;

		ata_sg_init(qc, sg, n_elem);
-		qc->nsect = buflen / ATA_SECT_SIZE;
+		qc->nsect = buflen / qc->sect_size;
		qc->nbytes = buflen;
	}

@@ -4004,7 +4004,7 @@

/**
- * 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.
@@ -4021,12 +4021,13 @@

	struct page *page;
	unsigned int offset;
	unsigned char *buf;

+ unsigned int sect_size = qc->sect_size;

	if (qc->cursect == (qc->nsect - 1))
		ap->hsm_task_state = HSM_ST_LAST;

	page = sg[qc->cursg].page;

- offset = sg[qc->cursg].offset + qc->cursg_ofs * ATA_SECT_SIZE;
+ offset = sg[qc->cursg].offset + qc->cursg_ofs * sect_size;

	/* get the current page and offset */
	page = nth_page(page, (offset >> PAGE_SHIFT));
@@ -4042,30 +4043,30 @@
		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, 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, sect_size, do_write);
	}

	qc->cursect++;
	qc->cursg_ofs++;

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

+	if ((qc->cursg_ofs * sect_size) == (&sg[qc->cursg])->length) {
		qc->cursg++;
		qc->cursg_ofs = 0;
	}
}

/**
- * 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
- * ATA device for the DRQ request.
+ * Transfer one or many qc->sect_size chunks of data
+ * from/to the ATA device for the DRQ request.
*
* LOCKING:
* Inherited from caller.

drivers/ata/libata-scsi.c +0 -0
diff -u --recursive --new-file --exclude='.*' --exclude='*.[osa]' --exclude='*.ko' --exclude='*.mod.c' linux-2.6.20/drivers/ata/libata-scsi.c new/drivers/ata/libata-scsi.c
@@ -2634,6 +2634,19 @@
		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 = cmd->request_bufflen;
+ }
+
/*
* Filter SET_FEATURES - XFER MODE command -- otherwise,
* SET_FEATURES - XFER MODE must be preceded/succeeded
@@ -2661,7 +2674,7 @@
* TODO: find out if we need to do more here to
* cover scatter/gather case.
*/
- qc->nsect = scmd->request_bufflen / ATA_SECT_SIZE;
+ qc->nsect = scmd->request_bufflen / qc->sect_size;

	/* request result TF */
	qc->flags |= ATA_QCFLAG_RESULT_TF;
include/linux/ata.h +0 -0
diff -u --recursive --new-file --exclude='.*' --exclude='*.[osa]' --exclude='*.ko' --exclude='*.mod.c' linux-2.6.20/include/linux/ata.h new/include/linux/ata.h
@@ -160,6 +160,12 @@
	/* 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 +0 -0
diff -u --recursive --new-file --exclude='.*' --exclude='*.[osa]' --exclude='*.ko' --exclude='*.mod.c' linux-2.6.20/include/linux/libata.h new/include/linux/libata.h
@@ -430,6 +430,7 @@
	int			dma_dir;

	unsigned int		pad_len;

+ unsigned int sect_size;

	unsigned int		nsect;
	unsigned int		cursect;
@@ -1155,6 +1156,7 @@
	qc->n_elem = 0;
	qc->err_mask = 0;
	qc->pad_len = 0;

+ qc->sect_size = 512;

	ata_tf_init(qc->dev, &qc->tf);
author
#1 lore raw

Re: [PATCH] libata: [take 2] add support for READ/WRITE LONG commands

[ take 2 -- s/cmd/scmd/; also fixed nbytes in libata-eh ]

The READ/WRITE LONG commands are theoretically obsolete, but most (all?) drives to date still implement them.

Of these, WRITE_LONG and WRITE_LONG_ONCE 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.

drivers/ata/libata-core.c +0 -0
diff -u --recursive --new-file --exclude='.*' --exclude='*.[osa]' --exclude='*.ko' --exclude='*.mod.c' linux-2.6.20/drivers/ata/libata-core.c new/drivers/ata/libata-core.c
@@ -1249,7 +1249,7 @@
			buflen += sg[i].length;

		ata_sg_init(qc, sg, n_elem);
-		qc->nsect = buflen / ATA_SECT_SIZE;
+		qc->nsect = buflen / qc->sect_size;
		qc->nbytes = buflen;
	}

@@ -4004,7 +4004,7 @@

/**
- * 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.
@@ -4021,12 +4021,13 @@

	struct page *page;
	unsigned int offset;
	unsigned char *buf;

+ unsigned int sect_size = qc->sect_size;

	if (qc->cursect == (qc->nsect - 1))
		ap->hsm_task_state = HSM_ST_LAST;

	page = sg[qc->cursg].page;

- offset = sg[qc->cursg].offset + qc->cursg_ofs * ATA_SECT_SIZE;
+ offset = sg[qc->cursg].offset + qc->cursg_ofs * sect_size;

	/* get the current page and offset */
	page = nth_page(page, (offset >> PAGE_SHIFT));
@@ -4042,30 +4043,30 @@
		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, 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, sect_size, do_write);
	}

	qc->cursect++;
	qc->cursg_ofs++;

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

+	if ((qc->cursg_ofs * sect_size) == (&sg[qc->cursg])->length) {
		qc->cursg++;
		qc->cursg_ofs = 0;
	}
}

/**
- * 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
- * ATA device for the DRQ request.
+ * Transfer one or many qc->sect_size chunks of data
+ * from/to the ATA device for the DRQ request.
*
* LOCKING:
* Inherited from caller.

drivers/ata/libata-eh.c +0 -0
diff -u --recursive --new-file --exclude='.*' --exclude='*.[osa]' --exclude='*.ko' --exclude='*.mod.c' linux-2.6.20/drivers/ata/libata-eh.c new/drivers/ata/libata-eh.c
@@ -1450,7 +1450,7 @@
 
		nbytes = qc->nbytes;
		if (!nbytes)

- nbytes = qc->nsect << 9;
+ nbytes = qc->nsect & qc->sect_size;

		ata_dev_printk(qc->dev, KERN_ERR,
			"cmd %02x/%02x:%02x:%02x:%02x:%02x/%02x:%02x:%02x:%02x:%02x/%02x "
drivers/ata/libata-scsi.c +0 -0
diff -u --recursive --new-file --exclude='.*' --exclude='*.[osa]' --exclude='*.ko' --exclude='*.mod.c' linux-2.6.20/drivers/ata/libata-scsi.c new/drivers/ata/libata-scsi.c
@@ -2634,6 +2634,19 @@
		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
@@ -2661,7 +2674,7 @@
* TODO: find out if we need to do more here to
* cover scatter/gather case.
*/
- qc->nsect = scmd->request_bufflen / ATA_SECT_SIZE;
+ qc->nsect = scmd->request_bufflen / qc->sect_size;

	/* request result TF */
	qc->flags |= ATA_QCFLAG_RESULT_TF;
include/linux/ata.h +0 -0
diff -u --recursive --new-file --exclude='.*' --exclude='*.[osa]' --exclude='*.ko' --exclude='*.mod.c' linux-2.6.20/include/linux/ata.h new/include/linux/ata.h
@@ -160,6 +160,12 @@
	/* 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 +0 -0
diff -u --recursive --new-file --exclude='.*' --exclude='*.[osa]' --exclude='*.ko' --exclude='*.mod.c' linux-2.6.20/include/linux/libata.h new/include/linux/libata.h
@@ -430,6 +430,7 @@
	int			dma_dir;

	unsigned int		pad_len;

+ unsigned int sect_size;

	unsigned int		nsect;
	unsigned int		cursect;
@@ -1155,6 +1156,7 @@
	qc->n_elem = 0;
	qc->err_mask = 0;
	qc->pad_len = 0;

+ qc->sect_size = 512;

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