diff --git a/fs/block_dev.c b/fs/block_dev.c index 4eeb69a88734..b721955d382e 100644 --- a/fs/block_dev.c +++ b/fs/block_dev.c @@ -852,6 +852,34 @@ struct block_device *open_by_devnum(dev_t dev, unsigned mode) EXPORT_SYMBOL(open_by_devnum); +/** + * check_disk_size_change - checks for disk size change and adjusts + * bdev size. + * + * @disk: struct gendisk to check + * @bdev: struct bdev to adjust. + * + * This routine checks to see if the bdev size does not match the disk size + * and adjusts it if it differs. + */ +void check_disk_size_change(struct gendisk *disk, struct block_device *bdev) +{ + loff_t disk_size, bdev_size; + + disk_size = (loff_t)get_capacity(disk) << 9; + bdev_size = i_size_read(bdev->bd_inode); + if (disk_size != bdev_size) { + char name[BDEVNAME_SIZE]; + + disk_name(disk, 0, name); + printk(KERN_INFO + "%s: detected capacity change from %lld to %lld\n", + name, bdev_size, disk_size); + i_size_write(bdev->bd_inode, disk_size); + } +} +EXPORT_SYMBOL(check_disk_size_change); + /** * revalidate_disk - wrapper for lower-level driver's revalidate_disk * call-back @@ -864,11 +892,20 @@ EXPORT_SYMBOL(open_by_devnum); */ int revalidate_disk(struct gendisk *disk) { + struct block_device *bdev; int ret = 0; if (disk->fops->revalidate_disk) ret = disk->fops->revalidate_disk(disk); + bdev = bdget_disk(disk, 0); + if (!bdev) + return ret; + + mutex_lock(&bdev->bd_mutex); + check_disk_size_change(disk, bdev); + mutex_unlock(&bdev->bd_mutex); + bdput(bdev); return ret; } EXPORT_SYMBOL(revalidate_disk); diff --git a/include/linux/fs.h b/include/linux/fs.h index d63461f97983..32477e8872d5 100644 --- a/include/linux/fs.h +++ b/include/linux/fs.h @@ -1722,6 +1722,8 @@ extern int fs_may_remount_ro(struct super_block *); */ #define bio_data_dir(bio) ((bio)->bi_rw & 1) +extern void check_disk_size_change(struct gendisk *disk, + struct block_device *bdev); extern int revalidate_disk(struct gendisk *); extern int check_disk_change(struct block_device *); extern int __invalidate_device(struct block_device *);