Fixed missing spaces displayed in journal_entry_dev_usage_to_text
while adjusting the display format to improve readability.

before:
```
 # bcachefs list_journal -a -t alloc:1:0 /dev/sdb
 ...
     dev_usage: dev=0free: buckets=233180 sectors=0 fragmented=0sb: buckets=13 sectors=6152 fragmented=504journal: buckets=1847 sectors=945664 fragmented=0btree: buckets=20 sectors=10240 fragmented=0user: buckets=1419 sectors=726513 fragmented=15cached: buckets=0 sectors=0 fragmented=0parity: buckets=0 sectors=0 fragmented=0stripe: buckets=0 sectors=0 fragmented=0need_gc_gens: buckets=0 sectors=0 fragmented=0need_discard: buckets=1 sectors=0 fragmented=0
```

after:
```
 # bcachefs list_journal -a -t alloc:1:0 /dev/sdb
 ...
     dev_usage: dev=0
       free: buckets=233180 sectors=0 fragmented=0
       sb: buckets=13 sectors=6152 fragmented=504
       journal: buckets=1847 sectors=945664 fragmented=0
       btree: buckets=20 sectors=10240 fragmented=0
       user: buckets=1419 sectors=726513 fragmented=15
       cached: buckets=0 sectors=0 fragmented=0
       parity: buckets=0 sectors=0 fragmented=0
       stripe: buckets=0 sectors=0 fragmented=0
       need_gc_gens: buckets=0 sectors=0 fragmented=0
       need_discard: buckets=1 sectors=0 fragmented=0
```
Signed-off-by: Youling Tang <tangyouling@kylinos.cn>

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

Before patch:
```
 #cat btrees/inodes/keys
 u64s 17 type inode_v3 0:4096:U32_MAX len 0 ver 0:   mode=40755
   flags= (16300000)
   bi_size=0
```

After patch:
```
 #cat btrees/inodes/keys
 u64s 17 type inode_v3 0:4096:U32_MAX len 0 ver 0:
   mode=40755
   flags=(16300000)
   bi_size=0
```

Signed-off-by: Youling Tang <tangyouling@kylinos.cn>
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>

Using filemap_read() can reduce unnecessary code execution
for non IOCB_DIRECT paths.

Signed-off-by: Youling Tang <tangyouling@kylinos.cn>
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>

fs-common.h needs dirent.h for enum bch_rename_mode

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

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

Use try_cmpxchg() family of functions instead of
cmpxchg (*ptr, old, new) == old. x86 CMPXCHG instruction returns
success in ZF flag, so this change saves a compare after cmpxchg
(and related move instruction in front of cmpxchg).

Also, try_cmpxchg() implicitly assigns old *ptr value to "old" when
cmpxchg fails. There is no need to re-read the value in the loop.

No functional change intended.

Signed-off-by: Uros Bizjak <ubizjak@gmail.com>
Cc: Kent Overstreet <kent.overstreet@linux.dev>
Cc: Brian Foster <bfoster@redhat.com>
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>

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

this is for the userspace metadata dump tool

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

A subsequent change will remove "read_only" as a mount option in favor
of the standard option "ro", meaning the userspace fsck command cannot
pass it to the fsck ioctl. Instead, in offline fsck, set "read_only"
kernel-side without trying to parse it as a mount option.

For compatibility with versions of the "bcachefs fsck" command that try
to pass the "read_only" mount opt, remove it from the mount options
string prior to parsing when it is present.

Signed-off-by: Thomas Bertschinger <tahbertschinger@gmail.com>
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>

When "read_only" is exposed as a mount option, it is redundant with the
standard option "ro" and gives users multiple ways to specify that a
bcachefs filesystem should be mounted read-only. This presents the risk
of having inconsistent options specified.

This can be seen when remounting a read-only filesystem in read-write
mode, using mount(8) from util-linux. Because mount(8) parses the
existing mount options from `/proc/mounts` and applies them when
remounting, it can end up applying both "read_only" and "rw":

$ mount img -o ro /mnt
$ strace mount -o remount,rw /mnt
...
fsconfig(4, FSCONFIG_SET_FLAG, "read_only", NULL, 0) = 0
fsconfig(4, FSCONFIG_SET_FLAG, "rw", NULL, 0) = 0
...

Making "read_only" no longer a mount option means this edge case cannot
occur.

Fixes: 62719cf ("bcachefs: Fix nochanges/read_only interaction")
Signed-off-by: Thomas Bertschinger <tahbertschinger@gmail.com>
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>

Add a new helper to fix inode_to_text()

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

The output of mount options such as "metadata_target" in `/proc/mounts`
uses the full path to the device.

mount(8) from util-linux uses the output from `/proc/mounts` to pass
existing mount options when performing a remount, so bcachefs should
accept as input the same form that it prints as output.

Without this change:

$ mount -t bcachefs -o metadata_target=vdb /dev/vdb /mnt
$ strace mount -o remount /mnt
...
fsconfig(4, FSCONFIG_SET_STRING, "metadata_target", "/dev/vdb", 0) = -1 EINVAL (Invalid argument)
...

Signed-off-by: Thomas Bertschinger <tahbertschinger@gmail.com>
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>

Consolidate duplicated checks for extents/dirents/xattrs - these keys
should all have a corresponding inode of the correct type.

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

Add a separate counter to bch_alloc_v4 for amount of striped data; this
lets us separately track striped and unstriped data in a bucket, which
lets us see when erasure coding has failed to update extents with stripe
pointers, and also find buckets to continue updating if we crash mid way
through creating a new stripe.

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

Add a new pseudo data type, to track buckets that are members of a
stripe, but have unstriped data in them.

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

New on disk format version for bch_alloc->stripe_sectors and
BCH_DATA_unstriped - accounting for unstriped data in stripe buckets.

Upgrade/downgrade requires regenerating alloc info - but only if erasure
coding is in use.

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

Mount options that take the name of a device that may be part of a
filesystem, for example "metadata_target", cannot be validated until
after the filesystem has been opened. However, an attempt to parse those
options may be made prior to the filesystem being opened.

This change adds a printbuf parameter to bch2_parse_mount_opts() which
will be used to save those mount options, when they are supplied prior
to the FS being opened, so that they can be parsed later.

This functionality is not currently needed, but will be used after
bcachefs starts using the new mount API to parse mount options. This is
because using the new mount API, we will process mount options prior to
opening the FS, but the new API doesn't provide a convenient way to
"replay" mount option parsing. So we save these options ourselves to
accomplish this.

This change also splits out the code to parse a single option into
bch2_parse_one_mount_opt(), which will be useful when using the new
mount API which deals with a single mount option at a time.

Signed-off-by: Thomas Bertschinger <tahbertschinger@gmail.com>
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>

This introduces a new error code, option_needs_open_fs, which is used to
indicate that an attempt was made to parse a mount option prior to
opening a filesystem, when that mount option requires an open filesystem
in order to be validated.

Returning this error results in bch2_parse_one_mount_opt() saving that
option for later parsing, after the filesystem is opened.

Signed-off-by: Thomas Bertschinger <tahbertschinger@gmail.com>
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>

This updates bcachefs to use the new mount API:

- Update the file_system_type to use the new init_fs_context()
  function.

- Define the new fs_context_operations functions.

- No longer register bch2_mount() and bch2_remount(); these are now
  called via the new fs_context functions.

- Define a new helper type, bch2_opts_parse that includes a struct
  bch_opts and additionally a printbuf used to save options that can't
  be parsed until after the FS is opened. This enables us to parse as
  many options as possible prior to opening the filesystem while saving
  those options that need the open FS for later parsing.

Signed-off-by: Thomas Bertschinger <tahbertschinger@gmail.com>
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>

New key type for the disk space accounting rewrite.

 - Holds a variable sized array of u64s (may be more than one for
   accounting e.g. compressed and uncompressed size, or buckets and
   sectors for a given data type)

 - Updates are deltas, not new versions of the key: this means updates
   to accounting can happen via the btree write buffer, which we'll be
   teaching to accumulate deltas.

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

Until accounting keys hit the btree, they are deltas, not new versions
of the existing key; this means we have to teach journal replay to
accumulate them.

Additionally, the journal doesn't track precisely which entries have
been flushed to the btree; it only tracks a range of entries that may
possibly still need to be flushed.

That means we need to compare accounting keys against the version in the
btree and only flush updates that are newer.

There's another wrinkle with the write buffer: if the write buffer
starts flushing accounting keys before journal replay has finished
flushing accounting keys, journal replay will see the version number
from the new updates and updates from the journal will be lost.

To avoid this, journal replay has to flush accounting keys first, and
we'll be adding a flag so that write buffer flush knows to hold
accounting keys until then.

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

Teach the btree write buffer how to accumulate accounting keys - instead
of having the newer key overwrite the older key as we do with other
updates, we need to add them together.

Also, add a flag so that write buffer flush knows when journal replay is
finished flushing accounting, and teach it to hold accounting keys until
that flag is set.

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>

This fixes a performance regression in journal replay; without
colaescing accounting keys we have multiple keys at the same position,
which means journal_keys_peek_upto() has to skip past many overwritten
keys - turning journal replay into an O(n^2) algorithm.

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

Reading disk accounting now requires an eytzinger lookup (see:
bch2_accounting_mem_read()), but the per-device counters are used
frequently enough that we'd like to still be able to read them with just
a percpu sum, as in the old code.

This patch special cases the device counters; when we update in-memory
accounting we also update the old style percpu counters if it's a deice
counter update.

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

Deleting code for the old disk accounting scheme.

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

This converts bch2_ioctl_fs_usage() to read from the new disk
accounting, via bch2_fs_replicas_usage_read().

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

With bch2_ioctl_fs_usage(), this is now dead code.

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

More ripping out of the old disk space accounting.

Note that the new disk space accounting is incompatible with the old,
and writing out old style disk space accounting with the new code is
infeasible.

This means upgrading and downgrading past this version requires
regenerating accounting.

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

More deletion of dead code.

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

Dead code.

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

More dead code deletion.

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

More dead code deletion

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

Rewrite fsck/gc for the new accounting scheme.

This adds a second set of in-memory accounting counters for gc to use;
like with other parts of gc we run all trigger in TRIGGER_GC mode, then
compare what we calculated to existing in-memory accounting at the end.

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

bch2_replicas_gc2() is used for garbage collection superblock replicas
entries that are empty - this converts it to the new accounting scheme.

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

Verify that the in-memory accounting verifies the on-disk accounting
after a clean shutdown.

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

This adds per-compression-type accounting of compressed and uncompressed
size as well as number of extents - meaning we can now see compression
ratio (without walking the whole filesystem).

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

We no longer have to walk the whole btree to calculate compression
stats.

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

Helper to show raw accounting in sysfs, mainly for debugging.

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

Helper to show raw accounting in sysfs, mainly for debugging.

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

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

Add counters for how much disk space we're using per btree.

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

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

The btree write buffer takes as input keys from the journal, sorts them,
deduplicates them, and flushes them back to the btree in sorted order.

The disk space accounting rewrite is moving accounting to normal btree
keys, with update (in this case deltas) accumulated in the write buffer
and then flushed to the btree; but this is going to increase the number
of keys handled by the write buffer by perhaps as much as a factor of
3x-5x.

The overhead from copying around and sorting this many keys would cause
a significant performance regression, but: there is huge locality in
updates to accounting keys that we can take advantage of.

Instead of appending accounting keys to the list of keys to be sorted,
this patch adds an eytzinger search tree of recently seen accounting
keys. We look up the accounting key in the eytzinger search tree and
apply the delta directly, adding it if it doesn't exist, and
periodically prune the eytzinger tree of unused entries.

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

Fold into bch2_fs_get_tree()

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

- improve error paths
- call bch2_fs_start() separately, after applying late-parsed options

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

Blocking the journal was needed to finish checking old style accounting,
but that code is gone and it's not needed in the alloc rewrite,
mark_lock is sufficient for synchronization.

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

Next change will move gc_alloc_start initialization into the alloc
trigger, so we have to mark those first.

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

Needed for online fsck; we need the trigger to initialize newly
allocated buckets and generation number changes while gc is running.

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

the order in which btree_gc walks keys have changed, so we no longer
have the sort of issues with online fsck this assertion was warning
about.

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

Make things more consistent and ensure that we're using u64 bitfields -
key types and btree ids are already around 32 bits.

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

fsck_err() now optionally takes a btree_trans; if the current thread has
one, it is required that it be passed.

The next patch will use this to unlock when waiting for user input.

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

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

We now read the line from the buffer atomically, which means we have to
allow the buffer to grow past STDIO_REDIRECT_BUFSIZE if we're waiting
for a full line - this behaviour is necessary for
stdio_redirect_readline_timeout() in the next patch.

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

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

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

Commit 0c0cbfd dropped the ctx->pos
update before the call to dir_emit. This breaks the userspace
implementation, causing the directory reads to be stuck in an infinite
loop. This doesn't happen in the kernel because the vfs handles the
updates to ctx->pos, but in the fuse implementation nobody updates
it.

Signed-off-by: Ariel Miculas <ariel.miculas@gmail.com>
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>

…cture

We already using mapping_set_error() in bch2_writepage_io_done(), so all
we need to do is to use file_check_and_advance_wb_err() when handling
fsync() requests in bch2_fsync().

Signed-off-by: Youling Tang <tangyouling@kylinos.cn>
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>

Add trace_bch2_sync_fs() and trace_bch2_fsync() implementations.

The output in trace is as follows:
  sync-29779   [000] .....   193.700935: bch2_sync_fs: dev 254,16 wait 1
  <...>-40027  [002] .....   342.535227: bch2_fsync: dev 254,32 ino 4099 parent 4096 datasync 1

Signed-off-by: Youling Tang <tangyouling@kylinos.cn>
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>

We're seeing a funny looking trans->locked assertion pop; we should be
after a bch2_trans_begin() call.

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

We can't hold locks while waiting for user input, that's a deadlock.

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

In this patch we add the FS_IOC_GETVERSION ioctl for getting
i_generation from inode, after that, users can list file's
generation number by using "lsattr".

Signed-off-by: Hongbo Li <lihongbo22@huawei.com>
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>

Implement support for FS_IOC_GETFSLABEL ioctl to read filesystem
label.

Signed-off-by: Hongbo Li <lihongbo22@huawei.com>
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>

Implement support for FS_IOC_SETFSLABEL ioctl to set filesystem
label.

Signed-off-by: Hongbo Li <lihongbo22@huawei.com>
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>

By removing the early-exit when REMAP_FILE_DEDUP is set, we should be
able to support the fideduperange ioctl, albeit less efficiently than if
we handled some of the extent locking and comparison logic inside
bcachefs.  Extent comparison logic already exists inside of
`__generic_remap_file_range_prep`.

Signed-off-by: Reed Riley <reed@riley.engineer>
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>

The commit 65bd442 ("bcachefs: bch2_btree_insert_trans() no longer
specifies BTREE_ITER_cached") removes BTREE_ITER_cached from
bch2_btree_insert_trans, which causes the update_inode function from
bcachefs-tools to take a long time (~20s).  Add an iter_flags parameter
to bch2_btree_insert, so the users can specify iter update trigger
flags, such as BTREE_ITER_cached.

Signed-off-by: Ariel Miculas <ariel.miculas@gmail.com>
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>

bch2_accounting_mem_insert() drops and retakes mark_lock; thus, we need
to check if the entry in question has already been inserted.

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

smatch warns that the copy of arg to userspace is a potential data
leak by virtue of arg.pad not being checked or zeroed. This was
introduced by the commit referenced below that switched arg from
being a zeroed runtime allocation to living on the stack. Fix by
simply zero initializing the structure.

Fixes: cde738a ("bcachefs: Convert bch2_ioctl_fs_usage() to new accounting")
Reported-by: Dan Carpenter <dan.carpenter@linaro.org>
Signed-off-by: Brian Foster <bfoster@redhat.com>
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>

Break up the percpu counter allocations into individual allocations for
each disk accounting counter; this fixes an issue on large systems where
we have too many replica entries to for the percpu allocator's max
practical size.

Also, use just one eytzinger tree for the normal set of counters and the
gc counters; this simplifies accounting_gc_done() where we need the same
set of counters to be present in both tables.

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

Add a new helper to free zeroed out accounting entries, and use it in
bch2_replicas_gc2(); bch2_replicas_gc2() was killing superblock replicas
entries if their corresponding accounting counters were nonzero, but
that's incorrect - the superblock replicas entry needs to exist if the
accounting entry exists, not if it's nonzero, because we check and
create the replicas entry when creating the new accounting entry - we
don't know when it's becoming nonzero.

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

The transaction commit path takes mark_lock, so we shouldn't be holding
it; use a bpos as an iterator so that we can drop and retake.

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

gc_pos is now based on keys, not nodes, for invariantness w.r.t. splits
and merges

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

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

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

we have a separate helper for releasing write locks

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

new helper - small refactoring

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

this is an internal implementation detail - and we're improving key
cache coherency

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

Signed-off-by: Brian Foster <bfoster@redhat.com>
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>

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

gc_lock is now only for synchronization between check_alloc_info and
interior btree updates - nothing else

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

Use FGP_WRITEBEGIN to avoid repeating the individual FGP flags before
starting a buffered write.

Signed-off-by: Pankaj Raghav <p.raghav@samsung.com>
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>

Set the preferred folio order in the fgp_flags by calling
fgf_set_order(). Page cache will try to allocate large folio of the
preferred order whenever possible instead of allocating multiple 0 order
folios.

This improves the buffered write performance up to 1.25x with default
mount options and up to 1.57x when mounted with no_data_io option with
the following fio workload:

fio --name=bcachefs --filename=/mnt/test  --size=100G \
     --ioengine=io_uring --iodepth=16 --rw=write --bs=128k

Signed-off-by: Pankaj Raghav <p.raghav@samsung.com>
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>

As part of improving btree key cache coherency, the bkey_cached.valid
flag is going away.

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

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

Add support for STATX_DIOALIGN to bcachefs, so that direct I/O alignment
restrictions are exposed to userspace in a generic way.

[Before]
```
./statx_test /mnt/bcachefs/test
statx(/mnt/bcachefs/test) = 0
dio mem align:0
dio offset align:0
```

[After]
```
./statx_test /mnt/bcachefs/test
statx(/mnt/bcachefs/test) = 0
dio mem align:1
dio offset align:512
```

Signed-off-by: Hongbo Li <lihongbo22@huawei.com>
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>

There's no reason for discards to be single threaded across all devices;
this will also help with fixing a race between the discard path and
device removal.

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

This adds a new helper, bch2_folio_reservation_get_partial(), which
reserves as many blocks as possible and may return partial success.

__bch2_buffered_write() is switched to the new helper - this fixes
fstests generic/275, the write until -ENOSPC test.

generic/230 now fails: this appears to be a test bug, where xfs_io isn't
looping after a partial write to get the error code.

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

This fixes an accounting mismatch for cached data.

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

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

Don't allocate the new bkey_cached until after we've done the btree
lookup; this means we can kill bkey_cached.valid.

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

Bumps [certifi](https://github.com/certifi/python-certifi) from 2023.7.22 to 2024.7.4.
- [Commits](certifi/python-certifi@2023.07.22...2024.07.04)

---
updated-dependencies:
- dependency-name: certifi
  dependency-type: direct:production
...

Signed-off-by: dependabot[bot] <support@github.com>