Iterating over backpointers on a specific device is potentially much
cheaper than walking all filesystem data.
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
Add a new data op to walk all data and metadata in a filesystem,
checking if it can be read successfully, and on error repairing from
another copy if possible.
- New helper: bch2_dev_idx_is_online(), so that we can bail out and
report to userspace when we're unable to scrub because the device is
offline
- data_update_opts, which controls the data move path, now understands
scrub: data is only read, not written. The read path is responsible
for rewriting on read error, as with other reads.
- scrub_pred skips data extents that don't have checksums
- bch_ioctl_data has a new scrub member, which has a data_types field
for data types to check - i.e. all data types, or only metadata.
- Add new entries to bch_move_stats so that we can report numbers for
corrected and uncorrected errors
- Add a new enum to bch_ioctl_data_event for explicitly reporting
completion and return code (i.e. device offline)
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
Add an ioctl for querying counters, the same ones provided in
/sys/fs/bcachefs/<uuid>/counters/, but more suitable for a 'bcachefs
top' command.
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
Add a new ioctl that can return the new accounting counter types; it
takes as input a bitmask of accounting types to return.
This will be used for returning e.g. compression accounting and
rebalance_work accounting.
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
Main part of the disk accounting rewrite.
This is a wholesale rewrite of the existing disk space accounting, which
relies on percepu counters that are sharded by journal buffer, and
rolled up and added to each journal write.
With the new scheme, every set of counters is a distinct key in the
accounting btree; this fixes scaling limitations of the old scheme,
where counters took up space in each journal entry and required multiple
percpu counters.
Now, in memory accounting requires a single set of percpu counters - not
multiple for each in flight journal buffer - and in the future we'll
probably also have counters that don't use in memory percpu counters,
they're not strictly required.
An accounting update is now a normal btree update, using the btree write
buffer path. At transaction commit time, we apply accounting updates to
the in memory counters, which are percpu counters indexed in an
eytzinger tree by the accounting key.
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
Fake flexible arrays (zero-length and one-element arrays) are
deprecated, and should be replaced by flexible-array members.
So, replace zero-length array with a flexible-array member in
`struct bch_ioctl_fsck_offline`.
Also annotate array `devs` with `__counted_by()` to prepare for the
coming implementation by GCC and Clang of the `__counted_by` attribute.
Flexible array members annotated with `__counted_by` can have their
accesses bounds-checked at run-time via `CONFIG_UBSAN_BOUNDS` (for
array indexing) and `CONFIG_FORTIFY_SOURCE` (for strcpy/memcpy-family
functions).
This fixes the following -Warray-bounds warnings:
fs/bcachefs/chardev.c: In function 'bch2_ioctl_fsck_offline':
fs/bcachefs/chardev.c:363:34: warning: array subscript 0 is outside array bounds of '__u64[0]' {aka 'long long unsigned int[]'} [-Warray-bounds=]
363 | if (copy_from_user(devs, &user_arg->devs[0], sizeof(user_arg->devs[0]) * arg.nr_devs)) {
| ^~~~~~~~~~~~~~~~~~
In file included from fs/bcachefs/chardev.c:5:
fs/bcachefs/bcachefs_ioctl.h:400:33: note: while referencing 'devs'
400 | __u64 devs[0];
This results in no differences in binary output.
Signed-off-by: Gustavo A. R. Silva <gustavoars@kernel.org>
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
This adds a new ioctl for running fsck on a mounted, in use filesystem.
This reuses the fsck_thread code from the previous patch for running
fsck on an offline, unmounted filesystem, so that log messages for the
fsck thread are redirected to userspace.
Only one running fsck instance is allowed at a time; a new semaphore
(since the lock will be taken by one thread and released by another) is
added for this.
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
This adds a new ioctl for running fsck on a list of devices.
Normally, if we wish to use the kernel's implementation of fsck we'd run
it at mount time with -o fsck. This ioctl lets us run fsck without
mounting, so that userspace bcachefs-tools can transparently switch to
the kernel's implementation of fsck when appropriate - primarily if the
kernel version of bcachefs better matches the filesystem on disk.
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
Fake flexible arrays (zero-length and one-element arrays) are
deprecated, and should be replaced by flexible-array members.
So, replace zero-length arrays with flexible-array members
in multiple structures.
Signed-off-by: Gustavo A. R. Silva <gustavoars@kernel.org>
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
BCH_IOCTL_DEV_USAGE mistakenly put the per-data-type array in struct
bch_ioctl_dev_usage; since ioctl numbers encode the size of the arg,
that means adding new data types breaks the ioctl.
This adds a new version that includes the number of data types as a
parameter: the old version is fixed at 10 so as to not break when adding
new types.
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
Previously, we were missing accounting for buckets in need_gc_gens and
need_discard states. This matters because buckets in those states need
other btree operations done before they can be used, so they can't be
conuted when checking current number of free buckets against the
allocation watermark.
Also, we weren't directly counting free buckets at all. Now, data type 0
== BCH_DATA_free, and free buckets are counted; this means we can get
rid of the separate (poorly defined) count of unavailable buckets.
This is a new on disk format version, with upgrade and fsck required for
the accounting changes.
Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com>
This patch adds subvolume.c - support for the subvolumes and snapshots
btrees and related data types and on disk data structures. The next
patches will start hooking up this new code to existing code.
Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com>
This adds a new data job type to scan for btree nodes in the old extent
format, and rewrite them.
Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com>
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
When the replicas mechanism was added, for tracking data by which drives
it's replicated on, the check for whether we have sufficient devices was
never updated to make use of it. This patch finally does that.
Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com>
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
When disk space accounting was changed to be tracked by replicas entry,
the ioctl interface was never update: this patch finally does that.
Aditionally, the BCH_IOCTL_USAGE ioctl is now broken out into separate
ioctls for filesystem and device usage.
Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com>
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
Initially forked from drivers/md/bcache, bcachefs is a new copy-on-write
filesystem with every feature you could possibly want.
Website: https://bcachefs.org
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
