Check for mismatches between casefold dirents and casefold directories.

A mismatch will cause lookups to fail, as we'll be doing the lookup with
the casefolded name, which won't match the non-casefolded dirent, and
vice versa.

Reported-by: Christopher Snowhill <chris@kode54.net>
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>

Replace with logging the error in the superblock.

Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>

Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>

We won't be root causing this in the immediate future, and it's fairly
innocuous - so just log it in the superblock.

https://github.com/koverstreet/bcachefs/issues/869

Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>

Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>

There are a few errors that needed to be marked as autofix.

Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>

Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>

This will likely mean that the btree had only one node - there was
nothing or almost nothing in it, and we should reconstruct and continue.

Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>

Build up and emit the error message for an inconsistency error all at
once, instead of spread over multiple printk calls, so they're not
jumbled in the dmesg log.

Also, add better indenting.

Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>

We weren't checking that accounting keys have the expected number of
accounters. Originally we probably wanted to be flexible on this, but it
doesn't look like that will be required - accounting is extended by
adding new counter types, not more counters to an existing type.

This means we can drop a BUG_ON() that popped once in automated testing,
and the new validation will make that bug easier to track down.

Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>