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#include <linux/sched.h> /* for capable() */
#include <linux/blkdev.h>
#include <linux/blkpg.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? */
down(&bdev->bd_sem);
if (disk->part[part - 1]) {
up(&bdev->bd_sem);
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)) {
up(&bdev->bd_sem);
return -EBUSY;
}
}
/* all seems OK */
add_partition(disk, part, start, length);
up(&bdev->bd_sem);
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;
down(&bdevp->bd_sem);
if (bdevp->bd_openers) {
up(&bdevp->bd_sem);
bdput(bdevp);
return -EBUSY;
}
/* all seems OK */
fsync_bdev(bdevp);
invalidate_bdev(bdevp, 0);
down(&bdev->bd_sem);
delete_partition(disk, part);
up(&bdev->bd_sem);
up(&bdevp->bd_sem);
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 (down_trylock(&bdev->bd_sem))
return -EBUSY;
res = rescan_partitions(disk, bdev);
up(&bdev->bd_sem);
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);
}
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;
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);
case BLKFLSBUF:
if (!capable(CAP_SYS_ADMIN))
return -EACCES;
if (disk->fops->ioctl) {
ret = disk->fops->ioctl(inode, file, cmd, arg);
/* -EINVAL to handle old uncorrected drivers */
if (ret != -EINVAL && ret != -ENOTTY)
return ret;
}
fsync_bdev(bdev);
invalidate_bdev(bdev, 0);
return 0;
case BLKROSET:
if (disk->fops->ioctl) {
ret = disk->fops->ioctl(inode, file, 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;
set_device_ro(bdev, n);
return 0;
default:
if (disk->fops->ioctl)
return disk->fops->ioctl(inode, file, cmd, arg);
}
return -ENOTTY;
}
/* 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);
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