#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? */ 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); } 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);