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| author |   Guo Chao <yan@linux.vnet.ibm.com> | 2013-02-21 15:16:46 -0800 |
|---|---|---|
| committer |   Jens Axboe <axboe@kernel.dk> | 2013-02-22 10:43:22 +0100 |
| commit | 541c742a7559eb65f0e36d3e2338c2ca532a3e61 (patch) | |
| tree | 73ac23dda59eb39cc026bc3264e21abaa077328a /drivers/block | |
| parent | loopdev: fix a deadlock (diff) | |
| download | linux-dev-541c742a7559eb65f0e36d3e2338c2ca532a3e61.tar.xz linux-dev-541c742a7559eb65f0e36d3e2338c2ca532a3e61.zip | |
loopdev: update block device size in loop_set_status()
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.
Signed-off-by: Guo Chao <yan@linux.vnet.ibm.com>
Reported-by: M. Hindess <hindessm@uk.ibm.com>
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Cc: Guo Chao <yan@linux.vnet.ibm.com>
Cc: Nikanth Karthikesan <knikanth@suse.de>
Cc: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Diffstat (limited to 'drivers/block')
| -rw-r--r-- | drivers/block/loop.c | 5 |
1 files changed, 5 insertions, 0 deletions
diff --git a/drivers/block/loop.c b/drivers/block/loop.c index 7f8065392064..ed850366f22d 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); |