kdave
btrfs-progs: mkfs/rootdir: add hard link support
With the recently reworked --rootdir support, although it solves several hard link related problems, it splits the hard links into new inodes.
And on each split, it shows a warning on each file with hardlinks.
Although the split behavior doesn't cause any data corruption, it can still be pretty noisy for rootfs creation, as there are a lot of distros storing timezone files as hardlinks.
This patchset adds back the hard link detection and creation, with enhanced handling to co-operate with --subvol option.
The details can be found in the first patch, with the new corner case introduced by --subvol option.
The second patch enhances the existing --rootdir and --subvol test case with extra corner cases like hard links, and hard links split by subvolume boundary.
Can you please rebase the branch? The diff is mixed with all the v6.10.1 changes, I can't do the review properly.
