libata-core.c

linux 内核源代码

/*
 *  libata-core.c - helper library for ATA
 *
 *  Maintained by:  Jeff Garzik <[e-mail]>
 *    		    Please ALWAYS copy [e-mail]
 *		    on emails.
 *
 *  Copyright 2003-2004 Red Hat, Inc.  All rights reserved.
 *  Copyright 2003-2004 Jeff Garzik
 *
 *
 *  This program is free software; you can redistribute it and/or modify
 *  it under the terms of the GNU General Public License as published by
 *  the Free Software Foundation; either version 2, or (at your option)
 *  any later version.
 *
 *  This program is distributed in the hope that it will be useful,
 *  but WITHOUT ANY WARRANTY; without even the implied warranty of
 *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 *  GNU General Public License for more details.
 *
 *  You should have received a copy of the GNU General Public License
 *  along with this program; see the file COPYING.  If not, write to
 *  the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA.
 *
 *
 *  libata documentation is available via 'make {ps|pdf}docs',
 *  as Documentation/DocBook/libata.*
 *
 *  Hardware documentation available from http://www.t13.org/ and
 *  http://www.sata-io.org/
 *
 *  Standards documents from:
 *	http://www.t13.org (ATA standards, PCI DMA IDE spec)
 *	http://www.t10.org (SCSI MMC - for ATAPI MMC)
 *	http://www.sata-io.org (SATA)
 *	http://www.compactflash.org (CF)
 *	http://www.qic.org (QIC157 - Tape and DSC)
 *	http://www.ce-ata.org (CE-ATA: not supported)
 *
 */

#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/pci.h>
#include <linux/init.h>
#include <linux/list.h>
#include <linux/mm.h>
#include <linux/highmem.h>
#include <linux/spinlock.h>
#include <linux/blkdev.h>
#include <linux/delay.h>
#include <linux/timer.h>
#include <linux/interrupt.h>
#include <linux/completion.h>
#include <linux/suspend.h>
#include <linux/workqueue.h>
#include <linux/jiffies.h>
#include <linux/scatterlist.h>
#include <linux/io.h>
#include <scsi/scsi.h>
#include <scsi/scsi_cmnd.h>
#include <scsi/scsi_host.h>
#include <linux/libata.h>
#include <asm/semaphore.h>
#include <asm/byteorder.h>
#include <linux/cdrom.h>

#include "libata.h"


/* debounce timing parameters in msecs { interval, duration, timeout } */
const unsigned long sata_deb_timing_normal[]		= {   5,  100, 2000 };
const unsigned long sata_deb_timing_hotplug[]		= {  25,  500, 2000 };
const unsigned long sata_deb_timing_long[]		= { 100, 2000, 5000 };

static unsigned int ata_dev_init_params(struct ata_device *dev,
					u16 heads, u16 sectors);
static unsigned int ata_dev_set_xfermode(struct ata_device *dev);
static unsigned int ata_dev_set_feature(struct ata_device *dev,
					u8 enable, u8 feature);
static void ata_dev_xfermask(struct ata_device *dev);
static unsigned long ata_dev_blacklisted(const struct ata_device *dev);

unsigned int ata_print_id = 1;
static struct workqueue_struct *ata_wq;

struct workqueue_struct *ata_aux_wq;

int atapi_enabled = 1;
module_param(atapi_enabled, int, 0444);
MODULE_PARM_DESC(atapi_enabled, "Enable discovery of ATAPI devices (0=off, 1=on)");

int atapi_dmadir = 0;
module_param(atapi_dmadir, int, 0444);
MODULE_PARM_DESC(atapi_dmadir, "Enable ATAPI DMADIR bridge support (0=off, 1=on)");

int atapi_passthru16 = 1;
module_param(atapi_passthru16, int, 0444);
MODULE_PARM_DESC(atapi_passthru16, "Enable ATA_16 passthru for ATAPI devices; on by default (0=off, 1=on)");

int libata_fua = 0;
module_param_named(fua, libata_fua, int, 0444);
MODULE_PARM_DESC(fua, "FUA support (0=off, 1=on)");

static int ata_ignore_hpa;
module_param_named(ignore_hpa, ata_ignore_hpa, int, 0644);
MODULE_PARM_DESC(ignore_hpa, "Ignore HPA limit (0=keep BIOS limits, 1=ignore limits, using full disk)");

static int libata_dma_mask = ATA_DMA_MASK_ATA|ATA_DMA_MASK_ATAPI|ATA_DMA_MASK_CFA;
module_param_named(dma, libata_dma_mask, int, 0444);
MODULE_PARM_DESC(dma, "DMA enable/disable (0x1==ATA, 0x2==ATAPI, 0x4==CF)");

static int ata_probe_timeout = ATA_TMOUT_INTERNAL / HZ;
module_param(ata_probe_timeout, int, 0444);
MODULE_PARM_DESC(ata_probe_timeout, "Set ATA probing timeout (seconds)");

int libata_noacpi = 0;
module_param_named(noacpi, libata_noacpi, int, 0444);
MODULE_PARM_DESC(noacpi, "Disables the use of ACPI in probe/suspend/resume when set");

MODULE_AUTHOR("Jeff Garzik");
MODULE_DESCRIPTION("Library module for ATA devices");
MODULE_LICENSE("GPL");
MODULE_VERSION(DRV_VERSION);


/**
 *	ata_tf_to_fis - Convert ATA taskfile to SATA FIS structure
 *	@tf: Taskfile to convert
 *	@pmp: Port multiplier port
 *	@is_cmd: This FIS is for command
 *	@fis: Buffer into which data will output
 *
 *	Converts a standard ATA taskfile to a Serial ATA
 *	FIS structure (Register - Host to Device).
 *
 *	LOCKING:
 *	Inherited from caller.
 */
void ata_tf_to_fis(const struct ata_taskfile *tf, u8 pmp, int is_cmd, u8 *fis)
{
	fis[0] = 0x27;			/* Register - Host to Device FIS */
	fis[1] = pmp & 0xf;		/* Port multiplier number*/
	if (is_cmd)
		fis[1] |= (1 << 7);	/* bit 7 indicates Command FIS */

	fis[2] = tf->command;
	fis[3] = tf->feature;

	fis[4] = tf->lbal;
	fis[5] = tf->lbam;
	fis[6] = tf->lbah;
	fis[7] = tf->device;

	fis[8] = tf->hob_lbal;
	fis[9] = tf->hob_lbam;
	fis[10] = tf->hob_lbah;
	fis[11] = tf->hob_feature;

	fis[12] = tf->nsect;
	fis[13] = tf->hob_nsect;
	fis[14] = 0;
	fis[15] = tf->ctl;

	fis[16] = 0;
	fis[17] = 0;
	fis[18] = 0;
	fis[19] = 0;
}

/**
 *	ata_tf_from_fis - Convert SATA FIS to ATA taskfile
 *	@fis: Buffer from which data will be input
 *	@tf: Taskfile to output
 *
 *	Converts a serial ATA FIS structure to a standard ATA taskfile.
 *
 *	LOCKING:
 *	Inherited from caller.
 */

void ata_tf_from_fis(const u8 *fis, struct ata_taskfile *tf)
{
	tf->command	= fis[2];	/* status */
	tf->feature	= fis[3];	/* error */

	tf->lbal	= fis[4];
	tf->lbam	= fis[5];
	tf->lbah	= fis[6];
	tf->device	= fis[7];

	tf->hob_lbal	= fis[8];
	tf->hob_lbam	= fis[9];
	tf->hob_lbah	= fis[10];

	tf->nsect	= fis[12];
	tf->hob_nsect	= fis[13];
}

static const u8 ata_rw_cmds[] = {
	/* pio multi */
	ATA_CMD_READ_MULTI,
	ATA_CMD_WRITE_MULTI,
	ATA_CMD_READ_MULTI_EXT,
	ATA_CMD_WRITE_MULTI_EXT,
	0,
	0,
	0,
	ATA_CMD_WRITE_MULTI_FUA_EXT,
	/* pio */
	ATA_CMD_PIO_READ,
	ATA_CMD_PIO_WRITE,
	ATA_CMD_PIO_READ_EXT,
	ATA_CMD_PIO_WRITE_EXT,
	0,
	0,
	0,
	0,
	/* dma */
	ATA_CMD_READ,
	ATA_CMD_WRITE,
	ATA_CMD_READ_EXT,
	ATA_CMD_WRITE_EXT,
	0,
	0,
	0,
	ATA_CMD_WRITE_FUA_EXT
};

/**
 *	ata_rwcmd_protocol - set taskfile r/w commands and protocol
 *	@tf: command to examine and configure
 *	@dev: device tf belongs to
 *
 *	Examine the device configuration and tf->flags to calculate
 *	the proper read/write commands and protocol to use.
 *
 *	LOCKING:
 *	caller.
 */
static int ata_rwcmd_protocol(struct ata_taskfile *tf, struct ata_device *dev)
{
	u8 cmd;

	int index, fua, lba48, write;

	fua = (tf->flags & ATA_TFLAG_FUA) ? 4 : 0;
	lba48 = (tf->flags & ATA_TFLAG_LBA48) ? 2 : 0;
	write = (tf->flags & ATA_TFLAG_WRITE) ? 1 : 0;

	if (dev->flags & ATA_DFLAG_PIO) {
		tf->protocol = ATA_PROT_PIO;
		index = dev->multi_count ? 0 : 8;
	} else if (lba48 && (dev->link->ap->flags & ATA_FLAG_PIO_LBA48)) {
		/* Unable to use DMA due to host limitation */
		tf->protocol = ATA_PROT_PIO;
		index = dev->multi_count ? 0 : 8;
	} else {
		tf->protocol = ATA_PROT_DMA;
		index = 16;
	}

	cmd = ata_rw_cmds[index + fua + lba48 + write];
	if (cmd) {
		tf->command = cmd;
		return 0;
	}
	return -1;
}

/**
 *	ata_tf_read_block - Read block address from ATA taskfile
 *	@tf: ATA taskfile of interest
 *	@dev: ATA device @tf belongs to
 *
 *	LOCKING:
 *	None.
 *
 *	Read block address from @tf.  This function can handle all
 *	three address formats - LBA, LBA48 and CHS.  tf->protocol and
 *	flags select the address format to use.
 *
 *	RETURNS:
 *	Block address read from @tf.
 */
u64 ata_tf_read_block(struct ata_taskfile *tf, struct ata_device *dev)
{
	u64 block = 0;

	if (tf->flags & ATA_TFLAG_LBA) {
		if (tf->flags & ATA_TFLAG_LBA48) {
			block |= (u64)tf->hob_lbah << 40;
			block |= (u64)tf->hob_lbam << 32;
			block |= tf->hob_lbal << 24;
		} else
			block |= (tf->device & 0xf) << 24;

		block |= tf->lbah << 16;
		block |= tf->lbam << 8;
		block |= tf->lbal;
	} else {
		u32 cyl, head, sect;

		cyl = tf->lbam | (tf->lbah << 8);
		head = tf->device & 0xf;
		sect = tf->lbal;

		block = (cyl * dev->heads + head) * dev->sectors + sect;
	}

	return block;
}

/**
 *	ata_build_rw_tf - Build ATA taskfile for given read/write request
 *	@tf: Target ATA taskfile
 *	@dev: ATA device @tf belongs to
 *	@block: Block address
 *	@n_block: Number of blocks
 *	@tf_flags: RW/FUA etc...
 *	@tag: tag
 *
 *	LOCKING:
 *	None.
 *
 *	Build ATA taskfile @tf for read/write request described by
 *	@block, @n_block, @tf_flags and @tag on @dev.
 *
 *	RETURNS:
 *
 *	0 on success, -ERANGE if the request is too large for @dev,
 *	-EINVAL if the request is invalid.
 */
int ata_build_rw_tf(struct ata_taskfile *tf, struct ata_device *dev,
		    u64 block, u32 n_block, unsigned int tf_flags,
		    unsigned int tag)
{
	tf->flags |= ATA_TFLAG_ISADDR | ATA_TFLAG_DEVICE;
	tf->flags |= tf_flags;

	if (ata_ncq_enabled(dev) && likely(tag != ATA_TAG_INTERNAL)) {
		/* yay, NCQ */
		if (!lba_48_ok(block, n_block))
			return -ERANGE;

		tf->protocol = ATA_PROT_NCQ;
		tf->flags |= ATA_TFLAG_LBA | ATA_TFLAG_LBA48;

		if (tf->flags & ATA_TFLAG_WRITE)
			tf->command = ATA_CMD_FPDMA_WRITE;
		else
			tf->command = ATA_CMD_FPDMA_READ;

		tf->nsect = tag << 3;
		tf->hob_feature = (n_block >> 8) & 0xff;
		tf->feature = n_block & 0xff;

		tf->hob_lbah = (block >> 40) & 0xff;
		tf->hob_lbam = (block >> 32) & 0xff;
		tf->hob_lbal = (block >> 24) & 0xff;
		tf->lbah = (block >> 16) & 0xff;
		tf->lbam = (block >> 8) & 0xff;
		tf->lbal = block & 0xff;

		tf->device = 1 << 6;
		if (tf->flags & ATA_TFLAG_FUA)
			tf->device |= 1 << 7;
	} else if (dev->flags & ATA_DFLAG_LBA) {
		tf->flags |= ATA_TFLAG_LBA;

		if (lba_28_ok(block, n_block)) {
			/* use LBA28 */
			tf->device |= (block >> 24) & 0xf;
		} else if (lba_48_ok(block, n_block)) {
			if (!(dev->flags & ATA_DFLAG_LBA48))
				return -ERANGE;

			/* use LBA48 */
			tf->flags |= ATA_TFLAG_LBA48;

			tf->hob_nsect = (n_block >> 8) & 0xff;

			tf->hob_lbah = (block >> 40) & 0xff;
			tf->hob_lbam = (block >> 32) & 0xff;
			tf->hob_lbal = (block >> 24) & 0xff;
		} else
			/* request too large even for LBA48 */
			return -ERANGE;

		if (unlikely(ata_rwcmd_protocol(tf, dev) < 0))
			return -EINVAL;

		tf->nsect = n_block & 0xff;

		tf->lbah = (block >> 16) & 0xff;
		tf->lbam = (block >> 8) & 0xff;
		tf->lbal = block & 0xff;

		tf->device |= ATA_LBA;
	} else {
		/* CHS */
		u32 sect, head, cyl, track;

		/* The request -may- be too large for CHS addressing. */
		if (!lba_28_ok(block, n_block))
			return -ERANGE;

		if (unlikely(ata_rwcmd_protocol(tf, dev) < 0))
			return -EINVAL;

		/* Convert LBA to CHS */
		track = (u32)block / dev->sectors;
		cyl   = track / dev->heads;
		head  = track % dev->heads;
		sect  = (u32)block % dev->sectors + 1;

		DPRINTK("block %u track %u cyl %u head %u sect %u\n",
			(u32)block, track, cyl, head, sect);

		/* Check whether the converted CHS can fit.
		   Cylinder: 0-65535
		   Head: 0-15
		   Sector: 1-255*/
		if ((cyl >> 16) || (head >> 4) || (sect >> 8) || (!sect))
			return -ERANGE;

		tf->nsect = n_block & 0xff; /* Sector count 0 means 256 sectors */
		tf->lbal = sect;
		tf->lbam = cyl;
		tf->lbah = cyl >> 8;
		tf->device |= head;
	}

	return 0;
}

/**
 *	ata_pack_xfermask - Pack pio, mwdma and udma masks into xfer_mask
 *	@pio_mask: pio_mask
 *	@mwdma_mask: mwdma_mask
 *	@udma_mask: udma_mask
 *
 *	Pack @pio_mask, @mwdma_mask and @udma_mask into a single
 *	unsigned int xfer_mask.
 *
 *	LOCKING:
 *	None.
 *
 *	RETURNS:
 *	Packed xfer_mask.
 */
static unsigned int ata_pack_xfermask(unsigned int pio_mask,
				      unsigned int mwdma_mask,
				      unsigned int udma_mask)
{
	return ((pio_mask << ATA_SHIFT_PIO) & ATA_MASK_PIO) |
		((mwdma_mask << ATA_SHIFT_MWDMA) & ATA_MASK_MWDMA) |
		((udma_mask << ATA_SHIFT_UDMA) & ATA_MASK_UDMA);
}

/**
 *	ata_unpack_xfermask - Unpack xfer_mask into pio, mwdma and udma masks
 *	@xfer_mask: xfer_mask to unpack
 *	@pio_mask: resulting pio_mask
 *	@mwdma_mask: resulting mwdma_mask
 *	@udma_mask: resulting udma_mask
 *
 *	Unpack @xfer_mask into @pio_mask, @mwdma_mask and @udma_mask.
 *	Any NULL distination masks will be ignored.
 */
static void ata_unpack_xfermask(unsigned int xfer_mask,
				unsigned int *pio_mask,
				unsigned int *mwdma_mask,
				unsigned int *udma_mask)
{
	if (pio_mask)
		*pio_mask = (xfer_mask & ATA_MASK_PIO) >> ATA_SHIFT_PIO;
	if (mwdma_mask)
		*mwdma_mask = (xfer_mask & ATA_MASK_MWDMA) >> ATA_SHIFT_MWDMA;
	if (udma_mask)
		*udma_mask = (xfer_mask & ATA_MASK_UDMA) >> ATA_SHIFT_UDMA;
}

static const struct ata_xfer_ent {
	int shift, bits;
	u8 base;
} ata_xfer_tbl[] = {
	{ ATA_SHIFT_PIO, ATA_BITS_PIO, XFER_PIO_0 },
	{ ATA_SHIFT_MWDMA, ATA_BITS_MWDMA, XFER_MW_DMA_0 },
	{ ATA_SHIFT_UDMA, ATA_BITS_UDMA, XFER_UDMA_0 },
	{ -1, },
};

/**
 *	ata_xfer_mask2mode - Find matching XFER_* for the given xfer_mask
 *	@xfer_mask: xfer_mask of interest
 *
 *	Return matching XFER_* value for @xfer_mask.  Only the highest
 *	bit of @xfer_mask is considered.
 *
 *	LOCKING:
 *	None.
 *
 *	RETURNS:
 *	Matching XFER_* value, 0 if no match found.
 */
static u8 ata_xfer_mask2mode(unsigned int xfer_mask)
{
	int highbit = fls(xfer_mask) - 1;
	const struct ata_xfer_ent *ent;

	for (ent = ata_xfer_tbl; ent->shift >= 0; ent++)
		if (highbit >= ent->shift && highbit < ent->shift + ent->bits)
			return ent->base + highbit - ent->shift;
	return 0;