block/ioctl.c - arm/linux-arm64-legacy - Git at Google

 #include <linux/capability.h>
 #include <linux/blkdev.h>
 #include <linux/blkpg.h>
 #include <linux/hdreg.h>
 #include <linux/backing-dev.h>
 #include <linux/buffer_head.h>
 #include <linux/smp_lock.h>
 #include <asm/uaccess.h>

 static int blkpg_ioctl(struct block_device *bdev, struct blkpg_ioctl_arg __user *arg)
 {
 	struct block_device *bdevp;
 	struct gendisk *disk;
 	struct blkpg_ioctl_arg a;
 	struct blkpg_partition p;
 	long long start, length;
 	int part;
 	int i;

 	if (!capable(CAP_SYS_ADMIN))
 		return -EACCES;
 	if (copy_from_user(&a, arg, sizeof(struct blkpg_ioctl_arg)))
 		return -EFAULT;
 	if (copy_from_user(&p, a.data, sizeof(struct blkpg_partition)))
 		return -EFAULT;
 	disk = bdev->bd_disk;
 	if (bdev != bdev->bd_contains)
 		return -EINVAL;
 	part = p.pno;
 	if (part <= 0 || part >= disk->minors)
 		return -EINVAL;
 	switch (a.op) {
 		case BLKPG_ADD_PARTITION:
 			start = p.start >> 9;
 			length = p.length >> 9;
 			/* check for fit in a hd_struct */
 			if (sizeof(sector_t) == sizeof(long) &&
 			    sizeof(long long) > sizeof(long)) {
 				long pstart = start, plength = length;
 				if (pstart != start || plength != length
 				    || pstart < 0 || plength < 0)
 					return -EINVAL;
 			}
 			/* partition number in use? */
 			mutex_lock(&bdev->bd_mutex);
 			if (disk->part[part - 1]) {
 				mutex_unlock(&bdev->bd_mutex);
 				return -EBUSY;
 			}
 			/* overlap? */
 			for (i = 0; i < disk->minors - 1; i++) {
 				struct hd_struct *s = disk->part[i];

 				if (!s)
 					continue;
 				if (!(start+length <= s->start_sect ||
 				      start >= s->start_sect + s->nr_sects)) {
 					mutex_unlock(&bdev->bd_mutex);
 					return -EBUSY;
 				}
 			}
 			/* all seems OK */
 			add_partition(disk, part, start, length);
 			mutex_unlock(&bdev->bd_mutex);
 			return 0;
 		case BLKPG_DEL_PARTITION:
 			if (!disk->part[part-1])
 				return -ENXIO;
 			if (disk->part[part - 1]->nr_sects == 0)
 				return -ENXIO;
 			bdevp = bdget_disk(disk, part);
 			if (!bdevp)
 				return -ENOMEM;
 			mutex_lock(&bdevp->bd_mutex);
 			if (bdevp->bd_openers) {
 				mutex_unlock(&bdevp->bd_mutex);
 				bdput(bdevp);
 				return -EBUSY;
 			}
 			/* all seems OK */
 			fsync_bdev(bdevp);
 			invalidate_bdev(bdevp, 0);

 			mutex_lock(&bdev->bd_mutex);
 			delete_partition(disk, part);
 			mutex_unlock(&bdev->bd_mutex);
 			mutex_unlock(&bdevp->bd_mutex);
 			bdput(bdevp);

 			return 0;
 		default:
 			return -EINVAL;
 	}
 }

 static int blkdev_reread_part(struct block_device *bdev)
 {
 	struct gendisk *disk = bdev->bd_disk;
 	int res;

 	if (disk->minors == 1 || bdev != bdev->bd_contains)
 		return -EINVAL;
 	if (!capable(CAP_SYS_ADMIN))
 		return -EACCES;
 	if (!mutex_trylock(&bdev->bd_mutex))
 		return -EBUSY;
 	res = rescan_partitions(disk, bdev);
 	mutex_unlock(&bdev->bd_mutex);
 	return res;
 }

 static int put_ushort(unsigned long arg, unsigned short val)
 {
 	return put_user(val, (unsigned short __user *)arg);
 }

 static int put_int(unsigned long arg, int val)
 {
 	return put_user(val, (int __user *)arg);
 }

 static int put_long(unsigned long arg, long val)
 {
 	return put_user(val, (long __user *)arg);
 }

 static int put_ulong(unsigned long arg, unsigned long val)
 {
 	return put_user(val, (unsigned long __user *)arg);
 }

 static int put_u64(unsigned long arg, u64 val)
 {
 	return put_user(val, (u64 __user *)arg);
 }

 static int blkdev_locked_ioctl(struct file *file, struct block_device *bdev,
 				unsigned cmd, unsigned long arg)
 {
 	struct backing_dev_info *bdi;
 	int ret, n;

 	switch (cmd) {
 	case BLKRAGET:
 	case BLKFRAGET:
 		if (!arg)
 			return -EINVAL;
 		bdi = blk_get_backing_dev_info(bdev);
 		if (bdi == NULL)
 			return -ENOTTY;
 		return put_long(arg, (bdi->ra_pages * PAGE_CACHE_SIZE) / 512);
 	case BLKROGET:
 		return put_int(arg, bdev_read_only(bdev) != 0);
 	case BLKBSZGET: /* get the logical block size (cf. BLKSSZGET) */
 		return put_int(arg, block_size(bdev));
 	case BLKSSZGET: /* get block device hardware sector size */
 		return put_int(arg, bdev_hardsect_size(bdev));
 	case BLKSECTGET:
 		return put_ushort(arg, bdev_get_queue(bdev)->max_sectors);
 	case BLKRASET:
 	case BLKFRASET:
 		if(!capable(CAP_SYS_ADMIN))
 			return -EACCES;
 		bdi = blk_get_backing_dev_info(bdev);
 		if (bdi == NULL)
 			return -ENOTTY;
 		bdi->ra_pages = (arg * 512) / PAGE_CACHE_SIZE;
 		return 0;
 	case BLKBSZSET:
 		/* set the logical block size */
 		if (!capable(CAP_SYS_ADMIN))
 			return -EACCES;
 		if (!arg)
 			return -EINVAL;
 		if (get_user(n, (int __user *) arg))
 			return -EFAULT;
 		if (bd_claim(bdev, file) < 0)
 			return -EBUSY;
 		ret = set_blocksize(bdev, n);
 		bd_release(bdev);
 		return ret;
 	case BLKPG:
 		return blkpg_ioctl(bdev, (struct blkpg_ioctl_arg __user *) arg);
 	case BLKRRPART:
 		return blkdev_reread_part(bdev);
 	case BLKGETSIZE:
 		if ((bdev->bd_inode->i_size >> 9) > ~0UL)
 			return -EFBIG;
 		return put_ulong(arg, bdev->bd_inode->i_size >> 9);
 	case BLKGETSIZE64:
 		return put_u64(arg, bdev->bd_inode->i_size);
 	}
 	return -ENOIOCTLCMD;
 }

 static int blkdev_driver_ioctl(struct inode *inode, struct file *file,
 		struct gendisk *disk, unsigned cmd, unsigned long arg)
 {
 	int ret;
 	if (disk->fops->unlocked_ioctl)
 		return disk->fops->unlocked_ioctl(file, cmd, arg);

 	if (disk->fops->ioctl) {
 		lock_kernel();
 		ret = disk->fops->ioctl(inode, file, cmd, arg);
 		unlock_kernel();
 		return ret;
 	}

 	return -ENOTTY;
 }

 int blkdev_ioctl(struct inode *inode, struct file *file, unsigned cmd,
 			unsigned long arg)
 {
 	struct block_device *bdev = inode->i_bdev;
 	struct gendisk *disk = bdev->bd_disk;
 	int ret, n;

 	switch(cmd) {
 	case BLKFLSBUF:
 		if (!capable(CAP_SYS_ADMIN))
 			return -EACCES;

 		ret = blkdev_driver_ioctl(inode, file, disk, cmd, arg);
 		/* -EINVAL to handle old uncorrected drivers */
 		if (ret != -EINVAL && ret != -ENOTTY)
 			return ret;

 		lock_kernel();
 		fsync_bdev(bdev);
 		invalidate_bdev(bdev, 0);
 		unlock_kernel();
 		return 0;

 	case BLKROSET:
 		ret = blkdev_driver_ioctl(inode, file, disk, cmd, arg);
 		/* -EINVAL to handle old uncorrected drivers */
 		if (ret != -EINVAL && ret != -ENOTTY)
 			return ret;
 		if (!capable(CAP_SYS_ADMIN))
 			return -EACCES;
 		if (get_user(n, (int __user *)(arg)))
 			return -EFAULT;
 		lock_kernel();
 		set_device_ro(bdev, n);
 		unlock_kernel();
 		return 0;
 	case HDIO_GETGEO: {
 		struct hd_geometry geo;

 		if (!arg)
 			return -EINVAL;
 		if (!disk->fops->getgeo)
 			return -ENOTTY;

 		/*
 		 * We need to set the startsect first, the driver may
 		 * want to override it.
 		 */
 		geo.start = get_start_sect(bdev);
 		ret = disk->fops->getgeo(bdev, &geo);
 		if (ret)
 			return ret;
 		if (copy_to_user((struct hd_geometry __user *)arg, &geo,
 					sizeof(geo)))
 			return -EFAULT;
 		return 0;
 	}
 	}

 	lock_kernel();
 	ret = blkdev_locked_ioctl(file, bdev, cmd, arg);
 	unlock_kernel();
 	if (ret != -ENOIOCTLCMD)
 		return ret;

 	return blkdev_driver_ioctl(inode, file, disk, cmd, arg);
 }

 /* Most of the generic ioctls are handled in the normal fallback path.
    This assumes the blkdev's low level compat_ioctl always returns
    ENOIOCTLCMD for unknown ioctls. */
 long compat_blkdev_ioctl(struct file *file, unsigned cmd, unsigned long arg)
 {
 	struct block_device *bdev = file->f_dentry->d_inode->i_bdev;
 	struct gendisk *disk = bdev->bd_disk;
 	int ret = -ENOIOCTLCMD;
 	if (disk->fops->compat_ioctl) {
 		lock_kernel();
 		ret = disk->fops->compat_ioctl(file, cmd, arg);
 		unlock_kernel();
 	}
 	return ret;
 }

 EXPORT_SYMBOL_GPL(blkdev_ioctl);
	#include <linux/capability.h>
	#include <linux/blkdev.h>
	#include <linux/blkpg.h>
	#include <linux/hdreg.h>
	#include <linux/backing-dev.h>
	#include <linux/buffer_head.h>
	#include <linux/smp_lock.h>
	#include <asm/uaccess.h>

	static int blkpg_ioctl(struct block_device bdev, struct blkpg_ioctl_arg __user arg)
	{
	struct block_device *bdevp;
	struct gendisk *disk;
	struct blkpg_ioctl_arg a;
	struct blkpg_partition p;
	long long start, length;
	int part;
	int i;

	if (!capable(CAP_SYS_ADMIN))
	return -EACCES;
	if (copy_from_user(&a, arg, sizeof(struct blkpg_ioctl_arg)))
	return -EFAULT;
	if (copy_from_user(&p, a.data, sizeof(struct blkpg_partition)))
	return -EFAULT;
	disk = bdev->bd_disk;
	if (bdev != bdev->bd_contains)
	return -EINVAL;
	part = p.pno;
	if (part <= 0 \|\| part >= disk->minors)
	return -EINVAL;
	switch (a.op) {
	case BLKPG_ADD_PARTITION:
	start = p.start >> 9;
	length = p.length >> 9;
	/* check for fit in a hd_struct */
	if (sizeof(sector_t) == sizeof(long) &&
	sizeof(long long) > sizeof(long)) {
	long pstart = start, plength = length;
	if (pstart != start \|\| plength != length
	\|\| pstart < 0 \|\| plength < 0)
	return -EINVAL;
	}
	/* partition number in use? */
	mutex_lock(&bdev->bd_mutex);
	if (disk->part[part - 1]) {
	mutex_unlock(&bdev->bd_mutex);
	return -EBUSY;
	}
	/* overlap? */
	for (i = 0; i < disk->minors - 1; i++) {
	struct hd_struct *s = disk->part[i];

	if (!s)
	continue;
	if (!(start+length <= s->start_sect \|\|
	start >= s->start_sect + s->nr_sects)) {
	mutex_unlock(&bdev->bd_mutex);
	return -EBUSY;
	}
	}
	/* all seems OK */
	add_partition(disk, part, start, length);
	mutex_unlock(&bdev->bd_mutex);
	return 0;
	case BLKPG_DEL_PARTITION:
	if (!disk->part[part-1])
	return -ENXIO;
	if (disk->part[part - 1]->nr_sects == 0)
	return -ENXIO;
	bdevp = bdget_disk(disk, part);
	if (!bdevp)
	return -ENOMEM;
	mutex_lock(&bdevp->bd_mutex);
	if (bdevp->bd_openers) {
	mutex_unlock(&bdevp->bd_mutex);
	bdput(bdevp);
	return -EBUSY;
	}
	/* all seems OK */
	fsync_bdev(bdevp);
	invalidate_bdev(bdevp, 0);

	mutex_lock(&bdev->bd_mutex);
	delete_partition(disk, part);
	mutex_unlock(&bdev->bd_mutex);
	mutex_unlock(&bdevp->bd_mutex);
	bdput(bdevp);

	return 0;
	default:
	return -EINVAL;
	}
	}

	static int blkdev_reread_part(struct block_device *bdev)
	{
	struct gendisk *disk = bdev->bd_disk;
	int res;

	if (disk->minors == 1 \|\| bdev != bdev->bd_contains)
	return -EINVAL;
	if (!capable(CAP_SYS_ADMIN))
	return -EACCES;
	if (!mutex_trylock(&bdev->bd_mutex))
	return -EBUSY;
	res = rescan_partitions(disk, bdev);
	mutex_unlock(&bdev->bd_mutex);
	return res;
	}

	static int put_ushort(unsigned long arg, unsigned short val)
	{
	return put_user(val, (unsigned short __user *)arg);
	}

	static int put_int(unsigned long arg, int val)
	{
	return put_user(val, (int __user *)arg);
	}

	static int put_long(unsigned long arg, long val)
	{
	return put_user(val, (long __user *)arg);
	}

	static int put_ulong(unsigned long arg, unsigned long val)
	{
	return put_user(val, (unsigned long __user *)arg);
	}

	static int put_u64(unsigned long arg, u64 val)
	{
	return put_user(val, (u64 __user *)arg);
	}

	static int blkdev_locked_ioctl(struct file file, struct block_device bdev,
	unsigned cmd, unsigned long arg)
	{
	struct backing_dev_info *bdi;
	int ret, n;

	switch (cmd) {
	case BLKRAGET:
	case BLKFRAGET:
	if (!arg)
	return -EINVAL;
	bdi = blk_get_backing_dev_info(bdev);
	if (bdi == NULL)
	return -ENOTTY;
	return put_long(arg, (bdi->ra_pages * PAGE_CACHE_SIZE) / 512);
	case BLKROGET:
	return put_int(arg, bdev_read_only(bdev) != 0);
	case BLKBSZGET: /* get the logical block size (cf. BLKSSZGET) */
	return put_int(arg, block_size(bdev));
	case BLKSSZGET: /* get block device hardware sector size */
	return put_int(arg, bdev_hardsect_size(bdev));
	case BLKSECTGET:
	return put_ushort(arg, bdev_get_queue(bdev)->max_sectors);
	case BLKRASET:
	case BLKFRASET:
	if(!capable(CAP_SYS_ADMIN))
	return -EACCES;
	bdi = blk_get_backing_dev_info(bdev);
	if (bdi == NULL)
	return -ENOTTY;
	bdi->ra_pages = (arg * 512) / PAGE_CACHE_SIZE;
	return 0;
	case BLKBSZSET:
	/* set the logical block size */
	if (!capable(CAP_SYS_ADMIN))
	return -EACCES;
	if (!arg)
	return -EINVAL;
	if (get_user(n, (int __user *) arg))
	return -EFAULT;
	if (bd_claim(bdev, file) < 0)
	return -EBUSY;
	ret = set_blocksize(bdev, n);
	bd_release(bdev);
	return ret;
	case BLKPG:
	return blkpg_ioctl(bdev, (struct blkpg_ioctl_arg __user *) arg);
	case BLKRRPART:
	return blkdev_reread_part(bdev);
	case BLKGETSIZE:
	if ((bdev->bd_inode->i_size >> 9) > ~0UL)
	return -EFBIG;
	return put_ulong(arg, bdev->bd_inode->i_size >> 9);
	case BLKGETSIZE64:
	return put_u64(arg, bdev->bd_inode->i_size);
	}
	return -ENOIOCTLCMD;
	}

	static int blkdev_driver_ioctl(struct inode inode, struct file file,
	struct gendisk *disk, unsigned cmd, unsigned long arg)
	{
	int ret;
	if (disk->fops->unlocked_ioctl)
	return disk->fops->unlocked_ioctl(file, cmd, arg);

	if (disk->fops->ioctl) {
	lock_kernel();
	ret = disk->fops->ioctl(inode, file, cmd, arg);
	unlock_kernel();
	return ret;
	}

	return -ENOTTY;
	}

	int blkdev_ioctl(struct inode inode, struct file file, unsigned cmd,
	unsigned long arg)
	{
	struct block_device *bdev = inode->i_bdev;
	struct gendisk *disk = bdev->bd_disk;
	int ret, n;

	switch(cmd) {
	case BLKFLSBUF:
	if (!capable(CAP_SYS_ADMIN))
	return -EACCES;

	ret = blkdev_driver_ioctl(inode, file, disk, cmd, arg);
	/* -EINVAL to handle old uncorrected drivers */
	if (ret != -EINVAL && ret != -ENOTTY)
	return ret;

	lock_kernel();
	fsync_bdev(bdev);
	invalidate_bdev(bdev, 0);
	unlock_kernel();
	return 0;

	case BLKROSET:
	ret = blkdev_driver_ioctl(inode, file, disk, cmd, arg);
	/* -EINVAL to handle old uncorrected drivers */
	if (ret != -EINVAL && ret != -ENOTTY)
	return ret;
	if (!capable(CAP_SYS_ADMIN))
	return -EACCES;
	if (get_user(n, (int __user *)(arg)))
	return -EFAULT;
	lock_kernel();
	set_device_ro(bdev, n);
	unlock_kernel();
	return 0;
	case HDIO_GETGEO: {
	struct hd_geometry geo;

	if (!arg)
	return -EINVAL;
	if (!disk->fops->getgeo)
	return -ENOTTY;

	/*
	* We need to set the startsect first, the driver may
	* want to override it.
	*/
	geo.start = get_start_sect(bdev);
	ret = disk->fops->getgeo(bdev, &geo);
	if (ret)
	return ret;
	if (copy_to_user((struct hd_geometry __user *)arg, &geo,
	sizeof(geo)))
	return -EFAULT;
	return 0;
	}
	}

	lock_kernel();
	ret = blkdev_locked_ioctl(file, bdev, cmd, arg);
	unlock_kernel();
	if (ret != -ENOIOCTLCMD)
	return ret;

	return blkdev_driver_ioctl(inode, file, disk, cmd, arg);
	}

	/* Most of the generic ioctls are handled in the normal fallback path.
	This assumes the blkdev's low level compat_ioctl always returns
	ENOIOCTLCMD for unknown ioctls. */
	long compat_blkdev_ioctl(struct file *file, unsigned cmd, unsigned long arg)
	{
	struct block_device *bdev = file->f_dentry->d_inode->i_bdev;
	struct gendisk *disk = bdev->bd_disk;
	int ret = -ENOIOCTLCMD;
	if (disk->fops->compat_ioctl) {
	lock_kernel();
	ret = disk->fops->compat_ioctl(file, cmd, arg);
	unlock_kernel();
	}
	return ret;
	}

	EXPORT_SYMBOL_GPL(blkdev_ioctl);