libata-scsi.c

linux 内核源代码

/*
 *  libata-scsi.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.t10.org/
 *  - http://www.t13.org/
 *
 */

#include <linux/kernel.h>
#include <linux/blkdev.h>
#include <linux/spinlock.h>
#include <scsi/scsi.h>
#include <scsi/scsi_host.h>
#include <scsi/scsi_cmnd.h>
#include <scsi/scsi_eh.h>
#include <scsi/scsi_device.h>
#include <scsi/scsi_tcq.h>
#include <scsi/scsi_transport.h>
#include <linux/libata.h>
#include <linux/hdreg.h>
#include <linux/uaccess.h>

#include "libata.h"

#define SECTOR_SIZE	512

typedef unsigned int (*ata_xlat_func_t)(struct ata_queued_cmd *qc);

static struct ata_device *__ata_scsi_find_dev(struct ata_port *ap,
					const struct scsi_device *scsidev);
static struct ata_device *ata_scsi_find_dev(struct ata_port *ap,
					    const struct scsi_device *scsidev);
static int ata_scsi_user_scan(struct Scsi_Host *shost, unsigned int channel,
			      unsigned int id, unsigned int lun);


#define RW_RECOVERY_MPAGE 0x1
#define RW_RECOVERY_MPAGE_LEN 12
#define CACHE_MPAGE 0x8
#define CACHE_MPAGE_LEN 20
#define CONTROL_MPAGE 0xa
#define CONTROL_MPAGE_LEN 12
#define ALL_MPAGES 0x3f
#define ALL_SUB_MPAGES 0xff


static const u8 def_rw_recovery_mpage[RW_RECOVERY_MPAGE_LEN] = {
	RW_RECOVERY_MPAGE,
	RW_RECOVERY_MPAGE_LEN - 2,
	(1 << 7),	/* AWRE */
	0,		/* read retry count */
	0, 0, 0, 0,
	0,		/* write retry count */
	0, 0, 0
};

static const u8 def_cache_mpage[CACHE_MPAGE_LEN] = {
	CACHE_MPAGE,
	CACHE_MPAGE_LEN - 2,
	0,		/* contains WCE, needs to be 0 for logic */
	0, 0, 0, 0, 0, 0, 0, 0, 0,
	0,		/* contains DRA, needs to be 0 for logic */
	0, 0, 0, 0, 0, 0, 0
};

static const u8 def_control_mpage[CONTROL_MPAGE_LEN] = {
	CONTROL_MPAGE,
	CONTROL_MPAGE_LEN - 2,
	2,	/* DSENSE=0, GLTSD=1 */
	0,	/* [QAM+QERR may be 1, see 05-359r1] */
	0, 0, 0, 0, 0xff, 0xff,
	0, 30	/* extended self test time, see 05-359r1 */
};

/*
 * libata transport template.  libata doesn't do real transport stuff.
 * It just needs the eh_timed_out hook.
 */
static struct scsi_transport_template ata_scsi_transport_template = {
	.eh_strategy_handler	= ata_scsi_error,
	.eh_timed_out		= ata_scsi_timed_out,
	.user_scan		= ata_scsi_user_scan,
};


static const struct {
	enum link_pm	value;
	const char	*name;
} link_pm_policy[] = {
	{ NOT_AVAILABLE, "max_performance" },
	{ MIN_POWER, "min_power" },
	{ MAX_PERFORMANCE, "max_performance" },
	{ MEDIUM_POWER, "medium_power" },
};

static const char *ata_scsi_lpm_get(enum link_pm policy)
{
	int i;

	for (i = 0; i < ARRAY_SIZE(link_pm_policy); i++)
		if (link_pm_policy[i].value == policy)
			return link_pm_policy[i].name;

	return NULL;
}

static ssize_t ata_scsi_lpm_put(struct class_device *class_dev,
	const char *buf, size_t count)
{
	struct Scsi_Host *shost = class_to_shost(class_dev);
	struct ata_port *ap = ata_shost_to_port(shost);
	enum link_pm policy = 0;
	int i;

	/*
	 * we are skipping array location 0 on purpose - this
	 * is because a value of NOT_AVAILABLE is displayed
	 * to the user as max_performance, but when the user
	 * writes "max_performance", they actually want the
	 * value to match MAX_PERFORMANCE.
	 */
	for (i = 1; i < ARRAY_SIZE(link_pm_policy); i++) {
		const int len = strlen(link_pm_policy[i].name);
		if (strncmp(link_pm_policy[i].name, buf, len) == 0 &&
		   buf[len] == '\n') {
			policy = link_pm_policy[i].value;
			break;
		}
	}
	if (!policy)
		return -EINVAL;

	ata_lpm_schedule(ap, policy);
	return count;
}

static ssize_t
ata_scsi_lpm_show(struct class_device *class_dev, char *buf)
{
	struct Scsi_Host *shost = class_to_shost(class_dev);
	struct ata_port *ap = ata_shost_to_port(shost);
	const char *policy =
		ata_scsi_lpm_get(ap->pm_policy);

	if (!policy)
		return -EINVAL;

	return snprintf(buf, 23, "%s\n", policy);
}
CLASS_DEVICE_ATTR(link_power_management_policy, S_IRUGO | S_IWUSR,
		ata_scsi_lpm_show, ata_scsi_lpm_put);
EXPORT_SYMBOL_GPL(class_device_attr_link_power_management_policy);

static void ata_scsi_invalid_field(struct scsi_cmnd *cmd,
				   void (*done)(struct scsi_cmnd *))
{
	ata_scsi_set_sense(cmd, ILLEGAL_REQUEST, 0x24, 0x0);
	/* "Invalid field in cbd" */
	done(cmd);
}

/**
 *	ata_std_bios_param - generic bios head/sector/cylinder calculator used by sd.
 *	@sdev: SCSI device for which BIOS geometry is to be determined
 *	@bdev: block device associated with @sdev
 *	@capacity: capacity of SCSI device
 *	@geom: location to which geometry will be output
 *
 *	Generic bios head/sector/cylinder calculator
 *	used by sd. Most BIOSes nowadays expect a XXX/255/16  (CHS)
 *	mapping. Some situations may arise where the disk is not
 *	bootable if this is not used.
 *
 *	LOCKING:
 *	Defined by the SCSI layer.  We don't really care.
 *
 *	RETURNS:
 *	Zero.
 */
int ata_std_bios_param(struct scsi_device *sdev, struct block_device *bdev,
		       sector_t capacity, int geom[])
{
	geom[0] = 255;
	geom[1] = 63;
	sector_div(capacity, 255*63);
	geom[2] = capacity;

	return 0;
}

/**
 *	ata_get_identity - Handler for HDIO_GET_IDENTITY ioctl
 *	@sdev: SCSI device to get identify data for
 *	@arg: User buffer area for identify data
 *
 *	LOCKING:
 *	Defined by the SCSI layer.  We don't really care.
 *
 *	RETURNS:
 *	Zero on success, negative errno on error.
 */
static int ata_get_identity(struct scsi_device *sdev, void __user *arg)
{
	struct ata_port *ap = ata_shost_to_port(sdev->host);
	struct ata_device *dev = ata_scsi_find_dev(ap, sdev);
	u16 __user *dst = arg;
	char buf[40];

	if (!dev)
		return -ENOMSG;

	if (copy_to_user(dst, dev->id, ATA_ID_WORDS * sizeof(u16)))
		return -EFAULT;

	ata_id_string(dev->id, buf, ATA_ID_PROD, ATA_ID_PROD_LEN);
	if (copy_to_user(dst + ATA_ID_PROD, buf, ATA_ID_PROD_LEN))
		return -EFAULT;

	ata_id_string(dev->id, buf, ATA_ID_FW_REV, ATA_ID_FW_REV_LEN);
	if (copy_to_user(dst + ATA_ID_FW_REV, buf, ATA_ID_FW_REV_LEN))
		return -EFAULT;

	ata_id_string(dev->id, buf, ATA_ID_SERNO, ATA_ID_SERNO_LEN);
	if (copy_to_user(dst + ATA_ID_SERNO, buf, ATA_ID_SERNO_LEN))
		return -EFAULT;

	return 0;
}

/**
 *	ata_cmd_ioctl - Handler for HDIO_DRIVE_CMD ioctl
 *	@scsidev: Device to which we are issuing command
 *	@arg: User provided data for issuing command
 *
 *	LOCKING:
 *	Defined by the SCSI layer.  We don't really care.
 *
 *	RETURNS:
 *	Zero on success, negative errno on error.
 */
int ata_cmd_ioctl(struct scsi_device *scsidev, void __user *arg)
{
	int rc = 0;
	u8 scsi_cmd[MAX_COMMAND_SIZE];
	u8 args[4], *argbuf = NULL, *sensebuf = NULL;
	int argsize = 0;
	enum dma_data_direction data_dir;
	int cmd_result;

	if (arg == NULL)
		return -EINVAL;

	if (copy_from_user(args, arg, sizeof(args)))
		return -EFAULT;

	sensebuf = kzalloc(SCSI_SENSE_BUFFERSIZE, GFP_NOIO);
	if (!sensebuf)
		return -ENOMEM;

	memset(scsi_cmd, 0, sizeof(scsi_cmd));

	if (args[3]) {
		argsize = SECTOR_SIZE * args[3];
		argbuf = kmalloc(argsize, GFP_KERNEL);
		if (argbuf == NULL) {
			rc = -ENOMEM;
			goto error;
		}

		scsi_cmd[1]  = (4 << 1); /* PIO Data-in */
		scsi_cmd[2]  = 0x0e;     /* no off.line or cc, read from dev,
					    block count in sector count field */
		data_dir = DMA_FROM_DEVICE;
	} else {
		scsi_cmd[1]  = (3 << 1); /* Non-data */
		scsi_cmd[2]  = 0x20;     /* cc but no off.line or data xfer */
		data_dir = DMA_NONE;
	}

	scsi_cmd[0] = ATA_16;

	scsi_cmd[4] = args[2];
	if (args[0] == WIN_SMART) { /* hack -- ide driver does this too... */
		scsi_cmd[6]  = args[3];
		scsi_cmd[8]  = args[1];
		scsi_cmd[10] = 0x4f;
		scsi_cmd[12] = 0xc2;
	} else {
		scsi_cmd[6]  = args[1];
	}
	scsi_cmd[14] = args[0];

	/* Good values for timeout and retries?  Values below
	   from scsi_ioctl_send_command() for default case... */
	cmd_result = scsi_execute(scsidev, scsi_cmd, data_dir, argbuf, argsize,
				  sensebuf, (10*HZ), 5, 0);

	if (driver_byte(cmd_result) == DRIVER_SENSE) {/* sense data available */
		u8 *desc = sensebuf + 8;
		cmd_result &= ~(0xFF<<24); /* DRIVER_SENSE is not an error */

		/* If we set cc then ATA pass-through will cause a
		 * check condition even if no error. Filter that. */
		if (cmd_result & SAM_STAT_CHECK_CONDITION) {
			struct scsi_sense_hdr sshdr;
			scsi_normalize_sense(sensebuf, SCSI_SENSE_BUFFERSIZE,
					     &sshdr);
			if (sshdr.sense_key == 0 &&
			    sshdr.asc == 0 && sshdr.ascq == 0)
				cmd_result &= ~SAM_STAT_CHECK_CONDITION;
		}

		/* Send userspace a few ATA registers (same as drivers/ide) */
		if (sensebuf[0] == 0x72 &&	/* format is "descriptor" */
		    desc[0] == 0x09) {		/* code is "ATA Descriptor" */
			args[0] = desc[13];	/* status */
			args[1] = desc[3];	/* error */
			args[2] = desc[5];	/* sector count (0:7) */
			if (copy_to_user(arg, args, sizeof(args)))
				rc = -EFAULT;
		}
	}


	if (cmd_result) {
		rc = -EIO;
		goto error;
	}

	if ((argbuf)
	 && copy_to_user(arg + sizeof(args), argbuf, argsize))
		rc = -EFAULT;
error:
	kfree(sensebuf);
	kfree(argbuf);
	return rc;
}

/**
 *	ata_task_ioctl - Handler for HDIO_DRIVE_TASK ioctl
 *	@scsidev: Device to which we are issuing command
 *	@arg: User provided data for issuing command
 *
 *	LOCKING:
 *	Defined by the SCSI layer.  We don't really care.
 *
 *	RETURNS:
 *	Zero on success, negative errno on error.
 */
int ata_task_ioctl(struct scsi_device *scsidev, void __user *arg)
{
	int rc = 0;
	u8 scsi_cmd[MAX_COMMAND_SIZE];
	u8 args[7], *sensebuf = NULL;
	int cmd_result;

	if (arg == NULL)
		return -EINVAL;

	if (copy_from_user(args, arg, sizeof(args)))
		return -EFAULT;

	sensebuf = kzalloc(SCSI_SENSE_BUFFERSIZE, GFP_NOIO);
	if (!sensebuf)
		return -ENOMEM;

	memset(scsi_cmd, 0, sizeof(scsi_cmd));
	scsi_cmd[0]  = ATA_16;
	scsi_cmd[1]  = (3 << 1); /* Non-data */
	scsi_cmd[2]  = 0x20;     /* cc but no off.line or data xfer */
	scsi_cmd[4]  = args[1];
	scsi_cmd[6]  = args[2];
	scsi_cmd[8]  = args[3];
	scsi_cmd[10] = args[4];
	scsi_cmd[12] = args[5];
	scsi_cmd[13] = args[6] & 0x4f;
	scsi_cmd[14] = args[0];

	/* Good values for timeout and retries?  Values below
	   from scsi_ioctl_send_command() for default case... */
	cmd_result = scsi_execute(scsidev, scsi_cmd, DMA_NONE, NULL, 0,
				sensebuf, (10*HZ), 5, 0);

	if (driver_byte(cmd_result) == DRIVER_SENSE) {/* sense data available */
		u8 *desc = sensebuf + 8;
		cmd_result &= ~(0xFF<<24); /* DRIVER_SENSE is not an error */

		/* If we set cc then ATA pass-through will cause a
		 * check condition even if no error. Filter that. */
		if (cmd_result & SAM_STAT_CHECK_CONDITION) {
			struct scsi_sense_hdr sshdr;
			scsi_normalize_sense(sensebuf, SCSI_SENSE_BUFFERSIZE,
						&sshdr);
			if (sshdr.sense_key == 0 &&
				sshdr.asc == 0 && sshdr.ascq == 0)
				cmd_result &= ~SAM_STAT_CHECK_CONDITION;
		}

		/* Send userspace ATA registers */
		if (sensebuf[0] == 0x72 &&	/* format is "descriptor" */
				desc[0] == 0x09) {/* code is "ATA Descriptor" */
			args[0] = desc[13];	/* status */
			args[1] = desc[3];	/* error */
			args[2] = desc[5];	/* sector count (0:7) */
			args[3] = desc[7];	/* lbal */
			args[4] = desc[9];	/* lbam */
			args[5] = desc[11];	/* lbah */
			args[6] = desc[12];	/* select */
			if (copy_to_user(arg, args, sizeof(args)))
				rc = -EFAULT;
		}
	}

	if (cmd_result) {
		rc = -EIO;
		goto error;
	}

 error:
	kfree(sensebuf);
	return rc;
}

int ata_scsi_ioctl(struct scsi_device *scsidev, int cmd, void __user *arg)
{
	int val = -EINVAL, rc = -EINVAL;

	switch (cmd) {
	case ATA_IOC_GET_IO32:
		val = 0;
		if (copy_to_user(arg, &val, 1))
			return -EFAULT;
		return 0;

	case ATA_IOC_SET_IO32:
		val = (unsigned long) arg;
		if (val != 0)
			return -EINVAL;
		return 0;

	case HDIO_GET_IDENTITY:
		return ata_get_identity(scsidev, arg);

	case HDIO_DRIVE_CMD:
		if (!capable(CAP_SYS_ADMIN) || !capable(CAP_SYS_RAWIO))
			return -EACCES;
		return ata_cmd_ioctl(scsidev, arg);

	case HDIO_DRIVE_TASK:
		if (!capable(CAP_SYS_ADMIN) || !capable(CAP_SYS_RAWIO))
			return -EACCES;
		return ata_task_ioctl(scsidev, arg);

	default:
		rc = -ENOTTY;
		break;
	}

	return rc;
}

/**
 *	ata_scsi_qc_new - acquire new ata_queued_cmd reference
 *	@dev: ATA device to which the new command is attached
 *	@cmd: SCSI command that originated this ATA command
 *	@done: SCSI command completion function
 *
 *	Obtain a reference to an unused ata_queued_cmd structure,
 *	which is the basic libata structure representing a single
 *	ATA command sent to the hardware.
 *
 *	If a command was available, fill in the SCSI-specific
 *	portions of the structure with information on the