#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 <linux/blktrace_api.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 hd_struct *part; 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) 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); mutex_unlock(&bdev->bd_mutex); return IS_ERR(part) ? PTR_ERR(part) : 0; 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; default: return -EINVAL; } } static int blkdev_reread_part(struct block_device *bdev) { struct gendisk *disk = bdev->bd_disk; int res; if (!disk_partitionable(disk) || 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 blk_ioctl_discard(struct block_device *bdev, uint64_t start, uint64_t len) { if (start & 511) return -EINVAL; if (len & 511) return -EINVAL; start >>= 9; len >>= 9; if (start + len > (bdev->bd_inode->i_size >> 9)) return -EINVAL; return blkdev_issue_discard(bdev, start, len, GFP_KERNEL, DISCARD_FL_WAIT); } 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; int ret; if (disk->fops->ioctl) return disk->fops->ioctl(bdev, mode, cmd, arg); if (disk->fops->locked_ioctl) { lock_kernel(); ret = disk->fops->locked_ioctl(bdev, mode, cmd, arg); unlock_kernel(); return ret; } 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); /* * always keep this in sync with compat_blkdev_ioctl() and * compat_blkdev_locked_ioctl() */ int blkdev_ioctl(struct block_device *bdev, fmode_t mode, unsigned cmd, unsigned long arg) { struct gendisk *disk = bdev->bd_disk; struct backing_dev_info *bdi; loff_t size; int ret, n; switch(cmd) { case BLKFLSBUF: if (!capable(CAP_SYS_ADMIN)) return -EACCES; ret = __blkdev_driver_ioctl(bdev, mode, cmd, arg); /* -EINVAL to handle old uncorrected drivers */ if (ret != -EINVAL && ret != -ENOTTY) return ret; lock_kernel(); fsync_bdev(bdev); invalidate_bdev(bdev); unlock_kernel(); return 0; case BLKROSET: ret = __blkdev_driver_ioctl(bdev, mode, 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 BLKDISCARD: { uint64_t range[2]; if (!(mode & FMODE_WRITE)) return -EBADF; if (copy_from_user(range, (void __user *)arg, sizeof(range))) return -EFAULT; return blk_ioctl_discard(bdev, range[0], range[1]); } 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; } 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 block device soft block size (cf. BLKSSZGET) */ return put_int(arg, block_size(bdev)); case BLKSSZGET: /* get block device logical block size */ return put_int(arg, bdev_logical_block_size(bdev)); case BLKPBSZGET: /* get block device physical block size */ return put_uint(arg, bdev_physical_block_size(bdev)); case BLKIOMIN: return put_uint(arg, bdev_io_min(bdev)); case BLKIOOPT: return put_uint(arg, bdev_io_opt(bdev)); case BLKALIGNOFF: return put_int(arg, bdev_alignment_offset(bdev)); case BLKSECTGET: return put_ushort(arg, queue_max_sectors(bdev_get_queue(bdev))); 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 (!(mode & FMODE_EXCL) && bd_claim(bdev, &bdev) < 0) return -EBUSY; ret = set_blocksize(bdev, n); if (!(mode & FMODE_EXCL)) bd_release(bdev); return ret; case BLKPG: lock_kernel(); ret = blkpg_ioctl(bdev, (struct blkpg_ioctl_arg __user *) arg); unlock_kernel(); break; case BLKRRPART: lock_kernel(); ret = blkdev_reread_part(bdev); unlock_kernel(); break; case BLKGETSIZE: size = bdev->bd_inode->i_size; if ((size >> 9) > ~0UL) return -EFBIG; return put_ulong(arg, size >> 9); case BLKGETSIZE64: return put_u64(arg, bdev->bd_inode->i_size); case BLKTRACESTART: case BLKTRACESTOP: case BLKTRACESETUP: case BLKTRACETEARDOWN: lock_kernel(); ret = blk_trace_ioctl(bdev, cmd, (char __user *) arg); unlock_kernel(); break; default: ret = __blkdev_driver_ioctl(bdev, mode, cmd, arg); } return ret; } EXPORT_SYMBOL_GPL(blkdev_ioctl);