Messages in this thread Patch in this message | | | From | Guo Chao <> | Subject | [PATCH 4/7] loopdev: update block device size in loop_set_status() | Date | Fri, 25 Jan 2013 18:56:19 +0800 |
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Loop device driver sometimes fails to impose the size limit on the device. Keep issuing following two commands:
losetup --offset 7517244416 --sizelimit 3224971264 /dev/loop0 backed_file blockdev --getsize64 /dev/loop0
blockdev reports file size instead of sizelimit several out of 100 times.
The problems are:
- losetup set up the device in two ioctl: LOOP_SET_FD and LOOP_SET_STATUS64.
- LOOP_SET_STATUS64 only update size of gendisk.
Block device size will be updated lazily when device comes to use. If udev rushes in between the two ioctl, it will bring in a block device whose size is backing file size. If the device is not released after LOOP_SET_STATUS64 ioctl, blockdev will not see the updated size.
Update block size in LOOP_SET_STATUS64 ioctl.
Reported-by: M. Hindess <hindessm@uk.ibm.com> Signed-off-by: Guo Chao <yan@linux.vnet.ibm.com> --- drivers/block/loop.c | 5 +++++ 1 file changed, 5 insertions(+)
diff --git a/drivers/block/loop.c b/drivers/block/loop.c index 7f80653..ed85036 100644 --- a/drivers/block/loop.c +++ b/drivers/block/loop.c @@ -1092,8 +1092,13 @@ loop_set_status(struct loop_device *lo, const struct loop_info64 *info) if (lo->lo_offset != info->lo_offset || lo->lo_sizelimit != info->lo_sizelimit) { + struct block_device *bdev = lo->lo_device; + if (figure_loop_size(lo, info->lo_offset, info->lo_sizelimit)) return -EFBIG; + + bd_set_size(bdev, (loff_t)get_capacity(bdev->bd_disk) << 9); + kobject_uevent(&disk_to_dev(bdev->bd_disk)->kobj, KOBJ_CHANGE); } loop_config_discard(lo); -- 1.7.9.5
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