btrfs partition fails to mount with open_ctree failed

Question

I have a btrfs partition that appears to be failing to mount. Here are the details:

(1) When I try to mount the partition, I get the following output in dmesg:

[791594.778798] BTRFS info (device sdf1): disk space caching is enabled
[791594.778801] BTRFS info (device sdf1): has skinny extents
[791594.781558] BTRFS error (device sdf1): parent transid verify failed on 21020672 wanted 8751 found 8847
[791594.781812] BTRFS error (device sdf1): parent transid verify failed on 21020672 wanted 8751 found 8847
[791594.781816] BTRFS error (device sdf1): failed to read chunk root
[791594.822945] BTRFS error (device sdf1): open_ctree failed

(2) I've tried mounting in ro/recovery mode with no luck.

(3) I've tried backing up the disk using btrfs recover with no luck.

(4) I've downloaded and built the latest btrfs-tools and btrfsck and friends seem to complain with the following message:

parent transid verify failed on 623312896 wanted 8755 found 8806
parent transid verify failed on 623312896 wanted 8755 found 8806
parent transid verify failed on 623312896 wanted 8755 found 8806
parent transid verify failed on 623312896 wanted 8755 found 8806
Ignoring transid failure
parent transid verify failed on 397623296 wanted 8563 found 8796
parent transid verify failed on 397623296 wanted 8563 found 8796
parent transid verify failed on 397623296 wanted 8563 found 8796
parent transid verify failed on 397623296 wanted 8563 found 8796
Ignoring transid failure
ERROR: child eb corrupted: parent bytenr=29425664 item=1 parent level=2 child level=0
ERROR: cannot open file system

Most interesting is the following log line which the devs seem to have added recently:

ERROR: child eb corrupted: parent bytenr=29425664 item=1 parent level=2 child level=0

Does anybody have any suggestions?