Re: [PATCH 25/45] block: simplify bdev/disk lookup in blkdev_get

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

 



On Sat, Nov 28, 2020 at 05:14:50PM +0100, Christoph Hellwig wrote:
> To simplify block device lookup and a few other upcoming areas, make sure
> that we always have a struct block_device available for each disk and
> each partition, and only find existing block devices in bdget.  The only
> downside of this is that each device and partition uses a little more
> memory.  The upside will be that a lot of code can be simplified.
> 
> With that all we need to look up the block device is to lookup the inode
> and do a few sanity checks on the gendisk, instead of the separate lookup
> for the gendisk.  For blk-cgroup which wants to access a gendisk without
> opening it, a new blkdev_{get,put}_no_open low-level interface is added
> to replace the previous get_gendisk use.
> 
> Note that the change to look up block device directly instead of the two
> step lookup using struct gendisk causes a subtile change in behavior:
> accessing a non-existing partition on an existing block device can now
> cause a call to request_module.  That call is harmless, and in practice
> no recent system will access these nodes as they aren't created by udev
> and static /dev/ setups are unusual.
> 
> Signed-off-by: Christoph Hellwig <hch@xxxxxx>

It's already merged but FWIW looks great to me.

Thank you.

-- 
tejun



[Index of Archives]     [Linux Ext4 Filesystem]     [Union Filesystem]     [Filesystem Testing]     [Ceph Users]     [Ecryptfs]     [AutoFS]     [Kernel Newbies]     [Share Photos]     [Security]     [Netfilter]     [Bugtraq]     [Yosemite News]     [MIPS Linux]     [ARM Linux]     [Linux Security]     [Linux Cachefs]     [Reiser Filesystem]     [Linux RAID]     [Samba]     [Device Mapper]     [CEPH Development]

  Powered by Linux