tree a44326e425ad5e6831e84e21469c2e37ba304cde
parent c8c24a7255f6b20cb57337cef27652518bebd64e
author Kelvin Zhang <zhangkelvin@google.com> 1667408847 -0700
committer Kelvin Zhang <zhangkelvin@google.com> 1667412086 -0700

Check for COW space before writing to COW

This gives a more detailed message when we run out of cow space.
Also, previously, it's possible that the COW op metadata writes
successfully but op data fails due to out of space, resulting in a
broken COW image. After this change, we won't write anything unless
there's sufficient space for both OP metadata and block data. This makes
COW operations more atomic and easier to debug/inspect.

Test: th
Change-Id: I6c1347e91b4ec2d7e434b47a0f47b290e288e600