ide.c

基于组件方式开发操作系统的OSKIT源代码

	for (unit = 0; unit < MAX_DRIVES; ++unit) {
		drive = &hwif->drives[unit];
		if (!drive->present)
			continue;
		if (drive->busy || drive->usage)
			goto abort;
		if (drive->driver != NULL && DRIVER(drive)->cleanup(drive))
			goto abort;
	}
	hwif->present = 0;
	
	/*
	 * All clear?  Then blow away the buffer cache
	 */
	sti();
	for (unit = 0; unit < MAX_DRIVES; ++unit) {
		drive = &hwif->drives[unit];
		if (!drive->present)
			continue;
		minor = drive->select.b.unit << PARTN_BITS;
		for (p = 0; p < (1<<PARTN_BITS); ++p) {
			if (drive->part[p].nr_sects > 0) {
				kdev_t devp = MKDEV(hwif->major, minor+p);
				struct super_block * sb = get_super(devp);
				if (sb) invalidate_inodes(sb);
				invalidate_buffers (devp);
			}
		}
	}
	cli();
	hwgroup = hwif->hwgroup;

	/*
	 * free the irq if we were the only hwif using it
	 */
	g = hwgroup->hwif;
	do {
		if (g->irq == hwif->irq)
			++irq_count;
		g = g->next;
	} while (g != hwgroup->hwif);
	if (irq_count == 1)
		free_irq(hwif->irq, hwgroup);

	/*
	 * Note that we only release the standard ports,
	 * and do not even try to handle any extra ports
	 * allocated for weird IDE interface chipsets.
	 */
	ide_release_region(hwif->io_ports[IDE_DATA_OFFSET], 8);
	ide_release_region(hwif->io_ports[IDE_CONTROL_OFFSET], 1);

	/*
	 * Remove us from the hwgroup, and free
	 * the hwgroup if we were the only member
	 */
	d = hwgroup->drive;
	for (i = 0; i < MAX_DRIVES; ++i) {
		drive = &hwif->drives[i];
		if (!drive->present)
			continue;
		while (hwgroup->drive->next != drive)
			hwgroup->drive = hwgroup->drive->next;
		hwgroup->drive->next = drive->next;
		if (hwgroup->drive == drive)
			hwgroup->drive = NULL;
		if (drive->id != NULL) {
			kfree(drive->id);
			drive->id = NULL;
		}
		drive->present = 0;
	}
	if (d->present)
		hwgroup->drive = d;
	while (hwgroup->hwif->next != hwif)
		hwgroup->hwif = hwgroup->hwif->next;
	hwgroup->hwif->next = hwif->next;
	if (hwgroup->hwif == hwif)
		kfree(hwgroup);
	else
		hwgroup->hwif = HWIF(hwgroup->drive);

#ifdef CONFIG_BLK_DEV_IDEDMA
	if (hwif->dma_base)
		(void) ide_release_dma(hwif);
#endif /* CONFIG_BLK_DEV_IDEDMA */

	/*
	 * Remove us from the kernel's knowledge
	 */
	unregister_blkdev(hwif->major, hwif->name);
	kfree(blksize_size[hwif->major]);
	kfree(max_sectors[hwif->major]);
	kfree(max_readahead[hwif->major]);
	blk_dev[hwif->major].request_fn = NULL;
	blk_dev[hwif->major].data = NULL;
	blk_dev[hwif->major].queue = NULL;
	blksize_size[hwif->major] = NULL;
	for (gdp = &gendisk_head; *gdp; gdp = &((*gdp)->next))
		if (*gdp == hwif->gd)
			break;
	if (*gdp == NULL)
		printk("gd not in disk chain!\n");
	else {
		gd = *gdp; *gdp = gd->next;
		kfree(gd->sizes);
		kfree(gd->part);
		kfree(gd);
	}
	init_hwif_data (index);	/* restore hwif data to pristine status */
abort:
	restore_flags(flags);	/* all CPUs */
#endif
}

int ide_register (int arg1, int arg2, int irq)
{
	int index, retry = 1;
	ide_hwif_t *hwif;
	ide_ioreg_t data_port = (ide_ioreg_t) arg1, ctl_port = (ide_ioreg_t) arg2;

	do {
		for (index = 0; index < MAX_HWIFS; ++index) {
			hwif = &ide_hwifs[index];
			if (hwif->io_ports[IDE_DATA_OFFSET] == data_port)
				goto found;
		}
		for (index = 0; index < MAX_HWIFS; ++index) {
			hwif = &ide_hwifs[index];
			if (!hwif->present)
				goto found;
		}
		for (index = 0; index < MAX_HWIFS; index++)
			ide_unregister(index);
	} while (retry--);
	return -1;
found:
	if (hwif->present)
		ide_unregister(index);
	if (hwif->present)
		return -1;
	ide_init_hwif_ports(hwif->io_ports, data_port, &hwif->irq);
	if (ctl_port)
		hwif->io_ports[IDE_CONTROL_OFFSET] = ctl_port;
	hwif->irq = irq;
	hwif->noprobe = 0;
	ide_init_module(IDE_PROBE_MODULE);
	ide_init_module(IDE_DRIVER_MODULE);
	return hwif->present ? index : -1;
}

void ide_add_setting(ide_drive_t *drive, const char *name, int rw, int read_ioctl, int write_ioctl, int data_type, int min, int max, int mul_factor, int div_factor, void *data, ide_procset_t *set)
{
	ide_settings_t **p = (ide_settings_t **) &drive->settings, *setting = NULL;

	while ((*p) && strcmp((*p)->name, name) < 0)
		p = &((*p)->next);
	if ((setting = kmalloc(sizeof(*setting), GFP_KERNEL)) == NULL)
		goto abort;
	memset(setting, 0, sizeof(*setting));
	if ((setting->name = kmalloc(strlen(name) + 1, GFP_KERNEL)) == NULL)
		goto abort;
	strcpy(setting->name, name);		setting->rw = rw;
	setting->read_ioctl = read_ioctl;	setting->write_ioctl = write_ioctl;
	setting->data_type = data_type;		setting->min = min;
	setting->max = max;			setting->mul_factor = mul_factor;
	setting->div_factor = div_factor;	setting->data = data;
	setting->set = set;			setting->next = *p;
	if (drive->driver)
		setting->auto_remove = 1;
	*p = setting;
	return;
abort:
	if (setting)
		kfree(setting);
}

void ide_remove_setting(ide_drive_t *drive, char *name)
{
	ide_settings_t **p = (ide_settings_t **) &drive->settings, *setting;

	while ((*p) && strcmp((*p)->name, name))
		p = &((*p)->next);
	if ((setting = (*p)) == NULL)
		return;
	(*p) = setting->next;
	kfree(setting->name);
	kfree(setting);
}

static ide_settings_t *ide_find_setting_by_ioctl(ide_drive_t *drive, int cmd)
{
	ide_settings_t *setting = drive->settings;

	while (setting) {
		if (setting->read_ioctl == cmd || setting->write_ioctl == cmd)
			break;
		setting = setting->next;
	}
	return setting;
}

ide_settings_t *ide_find_setting_by_name(ide_drive_t *drive, char *name)
{
	ide_settings_t *setting = drive->settings;

	while (setting) {
		if (strcmp(setting->name, name) == 0)
			break;
		setting = setting->next;
	}
	return setting;
}

static void auto_remove_settings(ide_drive_t *drive)
{
	ide_settings_t *setting;
repeat:
	setting = drive->settings;
	while (setting) {
		if (setting->auto_remove) {
			ide_remove_setting(drive, setting->name);
			goto repeat;
		}
		setting = setting->next;
	}
}

int ide_read_setting(ide_drive_t *drive, ide_settings_t *setting)
{
	int		val = -EINVAL;
	unsigned long	flags;

	if ((setting->rw & SETTING_READ)) {
		spin_lock_irqsave(&HWGROUP(drive)->spinlock, flags);
		switch(setting->data_type) {
			case TYPE_BYTE:
				val = *((u8 *) setting->data);
				break;
			case TYPE_SHORT:
				val = *((u16 *) setting->data);
				break;
			case TYPE_INT:
			case TYPE_INTA:
				val = *((u32 *) setting->data);
				break;
		}
		spin_unlock_irqrestore(&HWGROUP(drive)->spinlock, flags);
	}
	return val;
}

int ide_spin_wait_hwgroup (ide_drive_t *drive, unsigned long *flags)
{
	ide_hwgroup_t *hwgroup = HWGROUP(drive);
	unsigned long timeout = jiffies + (3 * HZ);

	spin_lock_irqsave(&hwgroup->spinlock, *flags);
	while (hwgroup->busy) {
		spin_unlock_irqrestore(&hwgroup->spinlock, *flags);
		__sti();	/* local CPU only; needed for jiffies */
		if (0 < (signed long)(jiffies - timeout)) {
			printk("%s: channel busy\n", drive->name);
			return -EBUSY;
		}
		spin_lock_irqsave(&hwgroup->spinlock, *flags);
	}
	return 0;
}

int ide_write_setting(ide_drive_t *drive, ide_settings_t *setting, int val)
{
	unsigned long flags;
	int i;
	u32 *p;

	if (!capable(CAP_SYS_ADMIN))
		return -EACCES;
	if (!(setting->rw & SETTING_WRITE))
		return -EPERM;
	if (val < setting->min || val > setting->max)
		return -EINVAL;
	if (setting->set)
		return setting->set(drive, val);
	if (ide_spin_wait_hwgroup(drive, &flags))
		return -EBUSY;
	switch (setting->data_type) {
		case TYPE_BYTE:
			*((u8 *) setting->data) = val;
			break;
		case TYPE_SHORT:
			*((u16 *) setting->data) = val;
			break;
		case TYPE_INT:
			*((u32 *) setting->data) = val;
			break;
		case TYPE_INTA:
			p = (u32 *) setting->data;
			for (i = 0; i < 1 << PARTN_BITS; i++, p++)
				*p = val;
			break;
	}
	spin_unlock_irqrestore(&HWGROUP(drive)->spinlock, flags);
	return 0;
}

static int set_io_32bit(ide_drive_t *drive, int arg)
{
	drive->io_32bit = arg;
#ifdef CONFIG_BLK_DEV_DTC2278
	if (HWIF(drive)->chipset == ide_dtc2278)
		HWIF(drive)->drives[!drive->select.b.unit].io_32bit = arg;
#endif /* CONFIG_BLK_DEV_DTC2278 */
	return 0;
}

static int set_using_dma(ide_drive_t *drive, int arg)
{
	if (!drive->driver || !DRIVER(drive)->supports_dma)
		return -EPERM;
	if (!drive->id || !(drive->id->capability & 1) || !HWIF(drive)->dmaproc)
		return -EPERM;
	if (HWIF(drive)->dmaproc(arg ? ide_dma_on : ide_dma_off, drive))
		return -EIO;
	return 0;
}

static int set_pio_mode(ide_drive_t *drive, int arg)
{
	struct request rq;

	if (!HWIF(drive)->tuneproc)
		return -ENOSYS;
	if (drive->special.b.set_tune)
		return -EBUSY;
	ide_init_drive_cmd(&rq);
	drive->tune_req = (byte) arg;
	drive->special.b.set_tune = 1;
	(void) ide_do_drive_cmd (drive, &rq, ide_wait);
	return 0;
}

void ide_add_generic_settings(ide_drive_t *drive)
{
/*
 *			drive	setting name		read/write access				read ioctl		write ioctl		data type	min	max				mul_factor	div_factor	data pointer			set function
 */
	ide_add_setting(drive,	"io_32bit",		drive->no_io_32bit ? SETTING_READ : SETTING_RW,	HDIO_GET_32BIT,		HDIO_SET_32BIT,		TYPE_BYTE,	0,	1 + (SUPPORT_VLB_SYNC << 1),	1,		1,		&drive->io_32bit,		set_io_32bit);
	ide_add_setting(drive,	"keepsettings",		SETTING_RW,					HDIO_GET_KEEPSETTINGS,	HDIO_SET_KEEPSETTINGS,	TYPE_BYTE,	0,	1,				1,		1,		&drive->keep_settings,		NULL);
	ide_add_setting(drive,	"nice1",		SETTING_RW,					-1,			-1,			TYPE_BYTE,	0,	1,				1,		1,		&drive->nice1,			NULL);
	ide_add_setting(drive,	"pio_mode",		SETTING_WRITE,					-1,			HDIO_SET_PIO_MODE,	TYPE_BYTE,	0,	255,				1,		1,		NULL,				set_pio_mode);
	ide_add_setting(drive,	"slow",			SETTING_RW,					-1,			-1,			TYPE_BYTE,	0,	1,				1,		1,		&drive->slow,			NULL);
	ide_add_setting(drive,	"unmaskirq",		drive->no_unmask ? SETTING_READ : SETTING_RW,	HDIO_GET_UNMASKINTR,	HDIO_SET_UNMASKINTR,	TYPE_BYTE,	0,	1,				1,		1,		&drive->unmask,			NULL);
	ide_add_setting(drive,	"using_dma",		SETTING_RW,					HDIO_GET_DMA,		HDIO_SET_DMA,		TYPE_BYTE,	0,	1,				1,		1,		&drive->using_dma,		set_using_dma);
}

int ide_wait_cmd (ide_drive_t *drive, int cmd, int nsect, int feature, int sectors, byte *buf)
{
	struct request rq;
	byte buffer[4];

	if (!buf)
		buf = buffer;
	memset(buf, 0, 4 + SECTOR_WORDS * 4 * sectors);
	ide_init_drive_cmd(&rq);
	rq.buffer = buf;
	*buf++ = cmd;
	*buf++ = nsect;
	*buf++ = feature;
	*buf++ = sectors;
	return ide_do_drive_cmd(drive, &rq, ide_wait);
}

static int ide_ioctl (struct inode *inode, struct file *file,
			unsigned int cmd, unsigned long arg)
{
	int err, major, minor;
	ide_drive_t *drive;
	struct request rq;
	kdev_t dev;
	ide_settings_t *setting;

	if (!inode || !(dev = inode->i_rdev))
		return -EINVAL;
	major = MAJOR(dev); minor = MINOR(dev);
	if ((drive = get_info_ptr(inode->i_rdev)) == NULL)
		return -ENODEV;

	if ((setting = ide_find_setting_by_ioctl(drive, cmd)) != NULL) {
		if (cmd == setting->read_ioctl) {
			err = ide_read_setting(drive, setting);
			return err >= 0 ? put_user(err, (long *) arg) : err;
		} else {
			if ((MINOR(inode->i_rdev) & PARTN_MASK))
				return -EINVAL;
			return ide_write_setting(drive, setting, arg);
		}
	}

	ide_init_drive_cmd (&rq);
	switch (cmd) {
		case HDIO_GETGEO:
		{
			struct hd_geometry *loc = (struct hd_geometry *) arg;
			if (!loc || (drive->media != ide_disk && drive->media != ide_floppy)) return -EINVAL;
			if (put_user(drive->bios_head, (byte *) &loc->heads)) return -EFAULT;
			if (put_user(drive->bios_sect, (byte *) &loc->sectors)) return -EFAULT;
			if (put_user(drive->bios_cyl, (unsigned short *) &loc->cylinders)) return -EFAULT;
			if (put_user((unsigned)drive->part[MINOR(inode->i_rdev)&PARTN_MASK].start_sect,
				(unsigned long *) &loc->start)) return -EFAULT;
			return 0;
		}
		case BLKSSZGET:
			/* Block size of media */
			return put_user(blksize_size[HWIF(drive)->major]
						    [minor&PARTN_MASK],
						    (int *)arg);
		
		case BLKFLSBUF:
			if (!capable(CAP_SYS_ADMIN)) return -EACCES;
			fsync_dev(inode->i_rdev);
			invalidate_buffers(inode->i_rdev);
			return 0;

	 	case BLKGETSIZE:   /* Return device size */
			return put_user(drive->part[MINOR(inode->i_rdev)&PARTN_MASK].nr_sects, (long *) arg);

		case BLKRRPART: /* Re-read partition tables */
			if (!capable(CAP_SYS_A