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#include <linux/capability.h>#include <linux/blkdev.h>#include <linux/export.h>#include <linux/gfp.h>#include <linux/blkpg.h>#include <linux/hdreg.h>#include <linux/backing-dev.h>#include <linux/fs.h>#include <linux/blktrace_api.h>#include <linux/pr.h>#include <linux/uaccess.h> static int blkpg_ioctl(struct block_device *bdev, struct blkpg_ioctl_arg __user *arg){	struct block_device *bdevp;	struct gendisk *disk;	struct hd_struct *part, *lpart;	struct blkpg_ioctl_arg a;	struct blkpg_partition p;	struct disk_part_iter piter;	long long start, length;	int partno; 	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;	partno = p.pno;	if (partno <= 0)		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 || partno > 65535)					return -EINVAL;			}			/* check if partition is aligned to blocksize */			if (p.start & (bdev_logical_block_size(bdev) - 1))				return -EINVAL; 			mutex_lock(&bdev->bd_mutex); 			/* overlap? */			disk_part_iter_init(&piter, disk,					    DISK_PITER_INCL_EMPTY);			while ((part = disk_part_iter_next(&piter))) {				if (!(start + length <= part->start_sect ||				      start >= part->start_sect + part->nr_sects)) {					disk_part_iter_exit(&piter);					mutex_unlock(&bdev->bd_mutex);					return -EBUSY;				}			}			disk_part_iter_exit(&piter); 			/* all seems OK */			part = add_partition(disk, partno, start, length,					     ADDPART_FLAG_NONE, NULL);			mutex_unlock(&bdev->bd_mutex);			return PTR_ERR_OR_ZERO(part);		case BLKPG_DEL_PARTITION:			part = disk_get_part(disk, partno);			if (!part)				return -ENXIO; 			bdevp = bdget(part_devt(part));			disk_put_part(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); 			mutex_lock_nested(&bdev->bd_mutex, 1);			delete_partition(disk, partno);			mutex_unlock(&bdev->bd_mutex);			mutex_unlock(&bdevp->bd_mutex);			bdput(bdevp); 			return 0;		case BLKPG_RESIZE_PARTITION:			start = p.start >> 9;			/* new length of partition in bytes */			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;			}			part = disk_get_part(disk, partno);			if (!part)				return -ENXIO;			bdevp = bdget(part_devt(part));			if (!bdevp) {				disk_put_part(part);				return -ENOMEM;			}			mutex_lock(&bdevp->bd_mutex);			mutex_lock_nested(&bdev->bd_mutex, 1);			if (start != part->start_sect) {				mutex_unlock(&bdevp->bd_mutex);				mutex_unlock(&bdev->bd_mutex);				bdput(bdevp);				disk_put_part(part);				return -EINVAL;			}			/* overlap? */			disk_part_iter_init(&piter, disk,					    DISK_PITER_INCL_EMPTY);			while ((lpart = disk_part_iter_next(&piter))) {				if (lpart->partno != partno &&				   !(start + length <= lpart->start_sect ||				   start >= lpart->start_sect + lpart->nr_sects)				   ) {					disk_part_iter_exit(&piter);					mutex_unlock(&bdevp->bd_mutex);					mutex_unlock(&bdev->bd_mutex);					bdput(bdevp);					disk_put_part(part);					return -EBUSY;				}			}			disk_part_iter_exit(&piter);			part_nr_sects_write(part, (sector_t)length);			i_size_write(bdevp->bd_inode, p.length);			mutex_unlock(&bdevp->bd_mutex);			mutex_unlock(&bdev->bd_mutex);			bdput(bdevp);			disk_put_part(part);			return 0;		default:			return -EINVAL;	}} /* * This is an exported API for the block driver, and will not * acquire bd_mutex. This API should be used in case that * caller has held bd_mutex already. */int __blkdev_reread_part(struct block_device *bdev){	struct gendisk *disk = bdev->bd_disk; 	if (!disk_part_scan_enabled(disk) || bdev != bdev->bd_contains)		return -EINVAL;	if (!capable(CAP_SYS_ADMIN))		return -EACCES; 	lockdep_assert_held(&bdev->bd_mutex); 	return rescan_partitions(disk, bdev);}EXPORT_SYMBOL(__blkdev_reread_part); /* * This is an exported API for the block driver, and will * try to acquire bd_mutex. If bd_mutex has been held already * in current context, please call __blkdev_reread_part(). * * Make sure the held locks in current context aren't required * in open()/close() handler and I/O path for avoiding ABBA deadlock: * - bd_mutex is held before calling block driver's open/close *   handler * - reading partition table may submit I/O to the block device */int blkdev_reread_part(struct block_device *bdev){	int res; 	mutex_lock(&bdev->bd_mutex);	res = __blkdev_reread_part(bdev);	mutex_unlock(&bdev->bd_mutex); 	return res;}EXPORT_SYMBOL(blkdev_reread_part); static int blk_ioctl_discard(struct block_device *bdev, fmode_t mode,		unsigned long arg, unsigned long flags){	uint64_t range[2];	uint64_t start, len; 	if (!(mode & FMODE_WRITE))		return -EBADF; 	if (copy_from_user(range, (void __user *)arg, sizeof(range)))		return -EFAULT; 	start = range[0];	len = range[1]; 	if (start & 511)		return -EINVAL;	if (len & 511)		return -EINVAL;	start >>= 9;	len >>= 9; 	if (start + len > (i_size_read(bdev->bd_inode) >> 9))		return -EINVAL;	return blkdev_issue_discard(bdev, start, len, GFP_KERNEL, flags);} static int blk_ioctl_zeroout(struct block_device *bdev, fmode_t mode,		unsigned long arg){	uint64_t range[2];	struct address_space *mapping;	uint64_t start, end, len; 	if (!(mode & FMODE_WRITE))		return -EBADF; 	if (copy_from_user(range, (void __user *)arg, sizeof(range)))		return -EFAULT; 	start = range[0];	len = range[1];	end = start + len - 1; 	if (start & 511)		return -EINVAL;	if (len & 511)		return -EINVAL;	if (end >= (uint64_t)i_size_read(bdev->bd_inode))		return -EINVAL;	if (end < start)		return -EINVAL; 	/* Invalidate the page cache, including dirty pages */	mapping = bdev->bd_inode->i_mapping;	truncate_inode_pages_range(mapping, start, end); 	return blkdev_issue_zeroout(bdev, start >> 9, len >> 9, GFP_KERNEL,			BLKDEV_ZERO_NOUNMAP);} 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_uint(unsigned long arg, unsigned int val){	return put_user(val, (unsigned 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);} int __blkdev_driver_ioctl(struct block_device *bdev, fmode_t mode,			unsigned cmd, unsigned long arg){	struct gendisk *disk = bdev->bd_disk; 	if (disk->fops->ioctl)		return disk->fops->ioctl(bdev, mode, cmd, arg); 	return -ENOTTY;}/* * For the record: _GPL here is only because somebody decided to slap it * on the previous export.  Sheer idiocy, since it wasn't copyrightable * at all and could be open-coded without any exports by anybody who cares. */EXPORT_SYMBOL_GPL(__blkdev_driver_ioctl); static int blkdev_pr_register(struct block_device *bdev,		struct pr_registration __user *arg){	const struct pr_ops *ops = bdev->bd_disk->fops->pr_ops;	struct pr_registration reg; 	if (!capable(CAP_SYS_ADMIN))		return -EPERM;	if (!ops || !ops->pr_register)		return -EOPNOTSUPP;	if (copy_from_user(&reg, arg, sizeof(reg)))		return -EFAULT; 	if (reg.flags & ~PR_FL_IGNORE_KEY)		return -EOPNOTSUPP;	return ops->pr_register(bdev, reg.old_key, reg.new_key, reg.flags);} static int blkdev_pr_reserve(struct block_device *bdev,		struct pr_reservation __user *arg){	const struct pr_ops *ops = bdev->bd_disk->fops->pr_ops;	struct pr_reservation rsv; 	if (!capable(CAP_SYS_ADMIN))		return -EPERM;	if (!ops || !ops->pr_reserve)		return -EOPNOTSUPP;	if (copy_from_user(&rsv, arg, sizeof(rsv)))		return -EFAULT; 	if (rsv.flags & ~PR_FL_IGNORE_KEY)		return -EOPNOTSUPP;	return ops->pr_reserve(bdev, rsv.key, rsv.type, rsv.flags);} static int blkdev_pr_release(struct block_device *bdev,		struct pr_reservation __user *arg){	const struct pr_ops *ops = bdev->bd_disk->fops->pr_ops;	struct pr_reservation rsv; 	if (!capable(CAP_SYS_ADMIN))		return -EPERM;	if (!ops || !ops->pr_release)		return -EOPNOTSUPP;	if (copy_from_user(&rsv, arg, sizeof(rsv)))		return -EFAULT; 	if (rsv.flags)		return -EOPNOTSUPP;	return ops->pr_release(bdev, rsv.key, rsv.type);} static int blkdev_pr_preempt(struct block_device *bdev,		struct pr_preempt __user *arg, bool abort){	const struct pr_ops *ops = bdev->bd_disk->fops->pr_ops;	struct pr_preempt p; 	if (!capable(CAP_SYS_ADMIN))		return -EPERM;	if (!ops || !ops->pr_preempt)		return -EOPNOTSUPP;	if (copy_from_user(&p, arg, sizeof(p)))		return -EFAULT; 	if (p.flags)		return -EOPNOTSUPP;	return ops->pr_preempt(bdev, p.old_key, p.new_key, p.type, abort);} static int blkdev_pr_clear(struct block_device *bdev,		struct pr_clear __user *arg){	const struct pr_ops *ops = bdev->bd_disk->fops->pr_ops;	struct pr_clear c; 	if (!capable(CAP_SYS_ADMIN))		return -EPERM;	if (!ops || !ops->pr_clear)		return -EOPNOTSUPP;	if (copy_from_user(&c, arg, sizeof(c)))		return -EFAULT; 	if (c.flags)		return -EOPNOTSUPP;	return ops->pr_clear(bdev, c.key);} /* * Is it an unrecognized ioctl? The correct returns are either * ENOTTY (final) or ENOIOCTLCMD ("I don't know this one, try a * fallback"). ENOIOCTLCMD gets turned into ENOTTY by the ioctl * code before returning. * * Confused drivers sometimes return EINVAL, which is wrong. It * means "I understood the ioctl command, but the parameters to * it were wrong". * * We should aim to just fix the broken drivers, the EINVAL case * should go away. */static inline int is_unrecognized_ioctl(int ret){	return	ret == -EINVAL ||		ret == -ENOTTY ||		ret == -ENOIOCTLCMD;} static int blkdev_flushbuf(struct block_device *bdev, fmode_t mode,		unsigned cmd, unsigned long arg){	int ret; 	if (!capable(CAP_SYS_ADMIN))		return -EACCES; 	ret = __blkdev_driver_ioctl(bdev, mode, cmd, arg);	if (!is_unrecognized_ioctl(ret))		return ret; 	fsync_bdev(bdev);	invalidate_bdev(bdev);	return 0;} static int blkdev_roset(struct block_device *bdev, fmode_t mode,		unsigned cmd, unsigned long arg){	int ret, n; 	ret = __blkdev_driver_ioctl(bdev, mode, cmd, arg);	if (!is_unrecognized_ioctl(ret))		return ret;	if (!capable(CAP_SYS_ADMIN))		return -EACCES;	if (get_user(n, (int __user *)arg))		return -EFAULT;	set_device_ro(bdev, n);	return 0;} static int blkdev_getgeo(struct block_device *bdev,		struct hd_geometry __user *argp){	struct gendisk *disk = bdev->bd_disk;	struct hd_geometry geo;	int ret; 	if (!argp)		return -EINVAL;	if (!disk->fops->getgeo)		return -ENOTTY; 	/*	 * We need to set the startsect first, the driver may	 * want to override it.	 */	memset(&geo, 0, sizeof(geo));	geo.start = get_start_sect(bdev);	ret = disk->fops->getgeo(bdev, &geo);	if (ret)		return ret;	if (copy_to_user(argp, &geo, sizeof(geo)))		return -EFAULT;	return 0;} /* set the logical block size */static int blkdev_bszset(struct block_device *bdev, fmode_t mode,		int __user *argp){	int ret, n; 	if (!capable(CAP_SYS_ADMIN))		return -EACCES;	if (!argp)		return -EINVAL;	if (get_user(n, argp))		return -EFAULT; 	if (!(mode & FMODE_EXCL)) {		bdgrab(bdev);		if (blkdev_get(bdev, mode | FMODE_EXCL, &bdev) < 0)			return -EBUSY;	} 	ret = set_blocksize(bdev, n);	if (!(mode & FMODE_EXCL))		blkdev_put(bdev, mode | FMODE_EXCL);	return ret;}

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