On Mon 21-10-19 11:27:36, Guoqing Jiang wrote:
>
>
> On 10/21/19 11:12 AM, Jan Kara wrote:
> > On Mon 21-10-19 10:49:54, Guoqing Jiang wrote:
> > >
> > > On 10/21/19 10:38 AM, Jan Kara wrote:
> > > > Currently, block device size in not updated on second and further open
> > > > for block devices where partition scan is disabled. This is particularly
> > > > annoying for example for DVD drives as that means block device size does
> > > > not get updated once the media is inserted into a drive if the device is
> > > > already open when inserting the media. This is actually always the case
> > > > for example when pktcdvd is in use.
> > > >
> > > > Fix the problem by revalidating block device size on every open even for
> > > > devices with partition scan disabled.
> > > >
> > > > Signed-off-by: Jan Kara <jack@xxxxxxx>
> > > > ---
> > > > fs/block_dev.c | 19 ++++++++++---------
> > > > 1 file changed, 10 insertions(+), 9 deletions(-)
> > > >
> > > > diff --git a/fs/block_dev.c b/fs/block_dev.c
> > > > index 88c6d35ec71d..d612468ee66b 100644
> > > > --- a/fs/block_dev.c
> > > > +++ b/fs/block_dev.c
> > > > @@ -1403,11 +1403,7 @@ static void flush_disk(struct block_device *bdev, bool kill_dirty)
> > > > "resized disk %s\n",
> > > > bdev->bd_disk ? bdev->bd_disk->disk_name : "");
> > > > }
> > > > -
> > > > - if (!bdev->bd_disk)
> > > > - return;
> > > > - if (disk_part_scan_enabled(bdev->bd_disk))
> > > > - bdev->bd_invalidated = 1;
> > > > + bdev->bd_invalidated = 1;
> > > > }
> > > > /**
> > > > @@ -1514,10 +1510,15 @@ static void __blkdev_put(struct block_device *bdev, fmode_t mode, int for_part);
> > > > static void bdev_disk_changed(struct block_device *bdev, bool invalidate)
> > > > {
> > > > - if (invalidate)
> > > > - invalidate_partitions(bdev->bd_disk, bdev);
> > > > - else
> > > > - rescan_partitions(bdev->bd_disk, bdev);
> > > > + if (disk_part_scan_enabled(bdev->bd_disk)) {
> > > > + if (invalidate)
> > > > + invalidate_partitions(bdev->bd_disk, bdev);
> > > > + else
> > > > + rescan_partitions(bdev->bd_disk, bdev);
> > > Maybe use the new common helper to replace above.
> > What do you mean exactly? Because there's only this place that has the code
> > pattern here...
>
> The above looks same as the new function.
>
> +static void bdev_disk_changed(struct block_device *bdev, bool invalidate)
> +{
> + if (invalidate)
> + invalidate_partitions(bdev->bd_disk, bdev);
> + else
> + rescan_partitions(bdev->bd_disk, bdev);
> +}
>
> So maybe just call it in the 'if' branch, am I misunderstand something?
I think you misparsed the diff ;) The code that you mention as duplicated
just gets reindented by the patch.
> static void bdev_disk_changed(struct block_device *bdev, bool invalidate)
> {
> if (disk_part_scan_enabled(bdev->bd_disk))
> bdev_disk_changed(bdev, invalidate)
> else {
> check_disk_size_change(bdev->bd_disk, bdev, !invalidate);
> bdev->bd_invalidated = 0;
> }
> }
This has infinite recursion in it - you call bdev_disk_changed() from
bdev_disk_changed().
Honza
--
Jan Kara <jack@xxxxxxxx>
SUSE Labs, CR
