bcachefs: Fix bch2_dev_btree_bitmap_marked_sectors() shift

Fixes: 27c15ed297cb bcachefs: bch_member.btree_allocated_bitmap
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>

bcachefs: bch_member.btree_allocated_bitmap

This adds a small (64 bit) per-device bitmap that tracks ranges that
have btree nodes, for accelerating btree node scan if it is ever needed.

- New helpers, bch2_dev_btree_bitmap_marked() and
bch2_dev_bitmap_mark(), for checking and updating the bitmap

- Interior btree update path updates the bitmaps when required

- The check_allocations pass has a new fsck_err check,
btree_bitmap_not_marked

- New on disk format version, mi_btree_mitmap, which indicates the new
bitmap is present

- Upgrade table lists the required recovery pass and expected fsck error

- Btree node scan uses the bitmap to skip ranges if we're on the new
version

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

bcachefs: for_each_member_device_rcu() now declares loop iter

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

bcachefs: for_each_member_device() now declares loop iter

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

bcachefs: simplify bch_devs_list

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

bcachefs: Move __bch2_members_v2_get_mut to sb-members.h

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

bcachefs: bch_sb_field_errors

Add a new superblock section to keep counts of errors seen since
filesystem creation: we'll be addingcounters for every distinct fsck
error.

The new superblock section has entries of the for [ id, count,
time_of_last_error ]; this is intended to let us see what errors are
occuring - and getting fixed - via show-super output.

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

bcachefs: Add IO error counts to bch_member

We now track IO errors per device since filesystem creation.

IO error counts can be viewed in sysfs, or with the 'bcachefs
show-super' command.

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

bcachefs: Rename bch_sb_field_members -> bch_sb_field_members_v1

Signed-off-by: Hunter Shaffer <huntershaffer182456@gmail.com>
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>

bcachefs: New superblock section members_v2

members_v2 has dynamically resizable entries so that we can extend
bch_member. The members can no longer be accessed with simple array
indexing Instead members_v2_get is used to find a member's exact
location within the array and returns a copy of that member.
Alternatively member_v2_get_mut retrieves a mutable point to a member.

Signed-off-by: Hunter Shaffer <huntershaffer182456@gmail.com>
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>

bcachefs: Add new helper to retrieve bch_member from sb

Prep work for introducing bch_sb_field_members_v2 - introduce new
helpers that will check for members_v2 if it exists, otherwise using v1

Signed-off-by: Hunter Shaffer <huntershaffer182456@gmail.com>
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>

bcachefs: sb-members.c

Split out a new file for bch_sb_field_members - we'll likely want to
move more code here in the future.

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