David Sterba wrote on 2016/02/24 13:38 +0100:

On Mon, Feb 22, 2016 at 02:59:52PM +0800, Qu Wenruo wrote:

quoted

Before this patchset, btrfs-find-root needs valid chunk tree from the
fs.
However for chunk root corrupted case, btrfs-find-root is of no use due
to above limitation.

This patchset will allow open_ctree_fs_info() to return a fs_info
without any valid tree root, but system chunk map from superblock only.
And modify btrfs-find-root along with some infrastructure to do chunk
root search.

Also fix an old bug where btrfs-find-root will always skip the first
chunk, with its corresponding regression test.

This also provides the basis for later "btrfsck --chunk-root" and faster
chunk-recovery enhancement.

Qu Wenruo (5):
   btrfs: volume: Fix a bug causing btrfs-find-root to skip first chunk
   btrfs: Allow open_ctree to return fs_info even chunk tree is corrupted
   btrfs: Add support for tree block operations on fs_info without roots.
   btrfs: find-root: Allow btrfs-find-root to search chunk root even
     chunk     root is corrupted
   btrfs: misc-test: Add regression test for find-root gives empty result

All applied, with minor adjustments. I'm not going to point them out
in the mails, please make a diff against your branch to see.

Thanks for the modification.
It's completely OK.

Thanks,
Qu