Commit Graph

1337255 Commits

Author SHA1 Message Date
Kent Overstreet
2adfa46734 bcachefs: btree node write errors now print btree node
It turned out a user was wondering why we were going read-only after a
write error, and he didn't realize he didn't have replication enabled -
this will make that more obvious, and we should be printing it anyways.

Link: https://www.reddit.com/r/bcachefs/comments/1jf9akl/large_data_transfers_switched_bcachefs_to_readonly/
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
2025-03-24 09:50:37 -04:00
Kent Overstreet
739200c573 bcachefs: Fix race in print_chain()
00636 Unable to handle kernel NULL pointer dereference at virtual address 00000000000000b0
00636 Mem abort info:
00636   ESR = 0x0000000096000005
00636   EC = 0x25: DABT (current EL), IL = 32 bits
00636   SET = 0, FnV = 0
00636   EA = 0, S1PTW = 0
00636   FSC = 0x05: level 1 translation fault
00636 Data abort info:
00636   ISV = 0, ISS = 0x00000005, ISS2 = 0x00000000
00636   CM = 0, WnR = 0, TnD = 0, TagAccess = 0
00636   GCS = 0, Overlay = 0, DirtyBit = 0, Xs = 0
00636 user pgtable: 4k pages, 39-bit VAs, pgdp=0000000101b10000
00636 [00000000000000b0] pgd=0000000000000000, p4d=0000000000000000, pud=0000000000000000
00636 Internal error: Oops: 0000000096000005 [#1] SMP
00636 Modules linked in:
00636 CPU: 12 UID: 0 PID: 79369 Comm: cat Not tainted 6.14.0-rc6-ktest-g3783b8973ab7 #17757
00636 Hardware name: linux,dummy-virt (DT)
00636 pstate: 20001005 (nzCv daif -PAN -UAO -TCO -DIT +SSBS BTYPE=--)
00636 pc : print_chain+0xb8/0x170
00636 lr : print_chain+0xa0/0x170
00636 sp : ffffff80d9c1bbb0
00636 x29: ffffff80d9c1bbb0 x28: 0000000000000002 x27: ffffff80c1be8250
00636 x26: ffffff80dd9b0000 x25: 0000000000000020 x24: 000000000000002d
00636 x23: 000000000000003c x22: ffffffc080a54518 x21: ffffff80da6e00d0
00636 x20: ffffff80da6e0170 x19: ffffff80c1a1d240 x18: 00000000ffffffff
00636 x17: 3535303937202d3c x16: 203139202d3c2035 x15: 00000000ffffffff
00636 x14: 0000000000000000 x13: ffffff80d71b63f1 x12: 0000000000000006
00636 x11: ffffffc080beb1c0 x10: 0000000000000020 x9 : 00000000000134cc
00636 x8 : 0000000000000020 x7 : 0000000000000004 x6 : 0000000000000020
00636 x5 : ffffff80d71b63f7 x4 : ffffffc080a5451b x3 : 0000000000000000
00636 x2 : 0000000000000000 x1 : 0000000000000000 x0 : 0000000000000000
00636 Call trace:
00636  print_chain+0xb8/0x170 (P)
00636  bch2_check_for_deadlock+0x444/0x5a0
00636  bch2_btree_deadlock_read+0xb4/0x1c8
00636  full_proxy_read+0x74/0xd8
00636  vfs_read+0x90/0x300

Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
2025-03-24 09:50:37 -04:00
Kent Overstreet
0b4fd56726 bcachefs: btree_trans_restart_foreign_task()
In debug mode, we save the call stack on transaction restart - but
there's no locking, so we can't touch it if we're issuing the restart
from another thread.

Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
2025-03-24 09:50:37 -04:00
Kent Overstreet
f4a584f4bf bcachefs: bch2_disk_accounting_mod2()
We're hitting some issues with uninitialized struct padding, flagged by
kmsan.

They appear to be falso positives, otherwise bch2_accounting_validate()
would have flagged them as "junk at end". But for now, we'll need to
initialize disk_accounting_pos with memset().

This adds a new helper, bch2_disk_accounting_mod2(), that initializes a
disk_accounting_pos and does the accounting mod all at once - so overall
things actually get slightly more ergonomic.

BCH_DISK_ACCOUNTING_replicas keys are left for now; KMSAN isn't warning
about them and they're a bit special.

Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
2025-03-24 09:50:37 -04:00
Kent Overstreet
5ae6f33053 bcachefs: zero init journal bios
fix a kmsan splat

Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
2025-03-24 09:50:37 -04:00
Kent Overstreet
9ea24b287b bcachefs: Eliminate padding in move_bucket_key
We appear to be tripping over a compiler/kmsan bug with padding fields -
this is an easy workaround.

Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
2025-03-24 09:50:37 -04:00
Kent Overstreet
1f88c35674 bcachefs: Fix a KMSAN splat in btree_update_nodes_written()
We may sometimes read from uninitialized memory; we know, and that's ok.

We check if a btree node has been reused before waiting on any
outstanding IO.

Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
2025-03-24 09:50:37 -04:00
Kent Overstreet
28aa859b6b bcachefs: kmsan asserts
Catching these early makes them a lot easier to track down.

Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
2025-03-24 09:50:36 -04:00
Kent Overstreet
53cf2a3daa bcachefs: Fix kmsan warnings in bch2_extent_crc_pack()
We store to all fields, so the kmsan warnings were spurious - but
initializing via stores to bitfields appear to have been giving the
compiler/kmsan trouble, and they're not necessary.

Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
2025-03-24 09:50:36 -04:00
Kent Overstreet
9c3a2c9b47 bcachefs: Disable asm memcpys when kmsan enabled
kmsan doesn't know about inline assembly, obviously; this will close a
ton of syzbot bugs.

Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
2025-03-24 09:50:36 -04:00
Kent Overstreet
962322475b bcachefs: Handle backpointers with unknown data types
New data types might be added later, so we don't want to disallow
unknown data types - that'll be a compatibility hassle later. Instead,
ignore them.

Reported-by: syzbot+3a290f5ff67ca3023834@syzkaller.appspotmail.com
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
2025-03-24 09:50:36 -04:00
Kent Overstreet
6a9f681ef6 bcachefs: Count BCH_DATA_parity backpointers correctly
These are counted as stripe data in the corresponding alloc keys.

Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
2025-03-24 09:50:36 -04:00
Kent Overstreet
04e90891be bcachefs: Run bch2_check_dirent_target() at lookup time
More on the "full online self healing" project:

We now run most of the dirent <-> inode consistency checks, with repair
code, at runtime - the exact same check and repair code that fsck runs.

This will allow us to repair the "dirent points to inode that does not
point back" inconsistencies that have been popping up at runtime.

Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
2025-03-24 09:50:36 -04:00
Kent Overstreet
9b0d00a369 bcachefs: Refactor bch2_check_dirent_target()
Prep work for calling bch2_check_dirent_target() from bch2_lookup().

- Add an inline wrapper, if the target and backpointer match we can skip
  the function call.

- We don't (yet?) want to remove the dirent we did the lookup from (when
  we find a directory or subvol with multiple valid dirents pointing to
  it), we can defer on that until later. For now, add an "are we in
  fsck?" parameter.

Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
2025-03-24 09:50:36 -04:00
Kent Overstreet
758ea4ff81 bcachefs: Move bch2_check_dirent_target() to namei.c
We're gradually running more and more fsck.c checks at runtime,
whereever applicable; when we do so they get moved out of fsck.c.

Next patch will call bch2_check_dirent_target() from bch2_lookup().

Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
2025-03-24 09:50:36 -04:00
Kent Overstreet
4fcd4de0a6 bcachefs: fs-common.c -> namei.c
name <-> inode, code for managing the relationships between inodes and
dirents.

Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
2025-03-24 09:50:36 -04:00
Kent Overstreet
8a9f3d0582 bcachefs: EIO cleanup
Replace these with proper private error codes, so that when we get an
error message we're not sifting through the entire codebase to see where
it came from.

Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
2025-03-24 09:50:36 -04:00
Kent Overstreet
127d90d282 bcachefs: bch2_write_prep_encoded_data() now returns errcode
Prep work for killing off EIO and replacing them with proper private
error codes.

Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
2025-03-24 09:50:36 -04:00
Kent Overstreet
2fe208303a bcachefs: Simplify bch2_write_op_error()
There's no reason for the caller to do the actual logging, it's all done
the same.

Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
2025-03-24 09:50:36 -04:00
Kent Overstreet
af2ff37da7 bcachefs: Fix block/btree node size defaults
We're fixing option parsing in userspace, it now obeys
OPT_SB_FIELD_SECTORS

Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
2025-03-24 09:50:35 -04:00
Alan Huang
5d361ae5af bcachefs: Add missing smp_rmb()
The smp_rmb() guarantees that reads from reservations.counter
occur before accessing cur_entry_u64s. It's paired with the
atomic64_try_cmpxchg in journal_entry_open.

Signed-off-by: Alan Huang <mmpgouride@gmail.com>
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
2025-03-24 09:50:35 -04:00
Kent Overstreet
4a4000b9a6 bcachefs: Kill JOURNAL_ERRORS()
Convert these to standard error codes, which means we can pass them
outside the journal code, they're easier to pass to tracepoints, etc.

Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
2025-03-24 09:50:35 -04:00
Kent Overstreet
80be08cdb5 bcachefs: Filesystem discard option now propagates to devices
the discard option is special, because it's both a filesystem and a
device option.

When set at the filesytsem level, it's supposed to propagate to (if set
persistently via sysfs) or override (if non persistently as a mount
option) the devices - that now works correctly.

Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
2025-03-24 09:50:35 -04:00
Kent Overstreet
8d7b7ac367 bcachefs: Device state is now a runtime option
Other options can normally be set at runtime via sysfs, no reason for
this one not to be as well - it just doesn't support the degraded flags
argument this way, that requires the ioctl.

Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
2025-03-24 09:50:35 -04:00
Kent Overstreet
7b84d934a1 bcachefs: Setting foreground_target at runtime now triggers rebalance
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
2025-03-24 09:50:35 -04:00
Kent Overstreet
8b294a9b5c bcachefs: Device options now use standard sysfs code
Device options now use the common code for sysfs, and can superblock
fields (in a struct bch_member).

This replaces BCH_DEV_OPT_SETTERS(), which was weird and easy to miss.

Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
2025-03-24 09:50:35 -04:00
Kent Overstreet
d2bad59255 bcachefs: Kill BCH_DEV_OPT_SETTERS()
Previously, device options had their superblock option field listed
separately, which was weird and easy to miss when defining options.

Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
2025-03-24 09:50:35 -04:00
Alan Huang
dd7ae389ff bcachefs: Remove spurious smp_mb()
The smp_mb() is paired with nothing.

Signed-off-by: Alan Huang <mmpgouride@gmail.com>
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
2025-03-24 09:50:35 -04:00
Alan Huang
5cc0ab39fb bcachefs: Fix incorrect state count
atomic64_read(&j->seq) - j->seq_write_started == JOURNAL_STATE_BUF_NR is
the condition in journal_entry_open where we return JOURNAL_ERR_max_open,
so journal_cur_seq(j) - seq == JOURNAL_STATE_BUF_NR means that the buf
corresponding to seq has started to write.

Signed-off-by: Alan Huang <mmpgouride@gmail.com>
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
2025-03-24 09:50:35 -04:00
Kent Overstreet
16a8d5d00b bcachefs: Fix btree iter flags in data move
Rebalance requires a not_extents iterator.

This wasn't hit before because all_snapshots disableds is_extents on
snapshots btrees - but has no effect on the reflink btree.

Reported-by: Maël Kerbiriou <mael.kerbiriou@free.fr>
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
2025-03-24 09:50:35 -04:00
Kent Overstreet
92c7789a9e bcachefs: Validate bch_sb.offset field
This was missed - but it needs to be correct for the superblock recovery
tool that scans the start and end of the device for backup superblocks:
we don't want to pick up superblocks that belong to a different
partition that starts at a different offset.

Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
2025-03-24 09:50:35 -04:00
Kent Overstreet
8bd875ae47 bcachefs: bch2_sb_validate() doesn't need bch_sb_handle
Minor refactoring, so that bch2_sb_validate() can be used in the new
userspace superblock recovery tool.

Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
2025-03-24 09:50:35 -04:00
Kent Overstreet
5e67243ea6 bcachefs: Add missing random.h includes
Fix build in userspace, and good hygeine.

Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
2025-03-24 09:50:34 -04:00
Kent Overstreet
2eb985c549 bcachefs: Better incompat version/feature error messages
If we can't mount because of an incompatibility, print what's supported
and unsupported - to help solve PEBKAC issues.

Reported-by: Roland Vet <vet.roland@protonmail.com>
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
2025-03-24 09:50:34 -04:00
Kent Overstreet
6aa446c05a bcachefs: Fix offset_into_extent in data move path
Fixes the following:

[   17.607394] kernel BUG at fs/bcachefs/reflink.c:261!
[   17.608316] Oops: invalid opcode: 0000 [#1] PREEMPT SMP NOPTI
[   17.608485] CPU: 0 UID: 0 PID: 564 Comm: bch-rebalance/3 Tainted: G           OE      6.14.0-rc6-arch1-gfcb0bd9609d2 #7 0efd7a8f4a00afeb2c5fb6e7ecb1aec8ddcbb1e1
[   17.608616] Tainted: [O]=OOT_MODULE, [E]=UNSIGNED_MODULE
[   17.608736] Hardware name: Micro-Star International Co., Ltd. MS-7D75/MAG B650 TOMAHAWK WIFI (MS-7D75), BIOS 1.74 08/01/2023
[   17.608855] RIP: 0010:bch2_lookup_indirect_extent+0x252/0x290 [bcachefs]
[   17.609006] Code: 00 00 00 00 e8 7f 51 f5 ff 89 c3 85 c0 74 52 48 8b 7d b0 4c 89 ee e8 4d 4b f4 ff 48 63 d3 48 89 d0 31 d2 e9 2e ff ff ff 0f 0b <0f> 0b 48 8b 7d b0 4c 89 ee 48 89 55 a8 e8 2c 4b f4 ff 4c 8b 55 a8
[   17.609136] RSP: 0018:ffffa3714455f850 EFLAGS: 00010246
[   17.609261] RAX: 0000000000000080 RBX: ffff895891098790 RCX: 0000000000000000
[   17.609387] RDX: 0000000000000080 RSI: ffffa3714455fa90 RDI: ffff895889550000
[   17.609511] RBP: ffffa3714455f8c0 R08: ffff895891098790 R09: 0000000000000001
[   17.609637] R10: ffffa3714455f8d8 R11: ffffa3714455f950 R12: ffffa3714455fa58
[   17.609763] R13: ffff895891098790 R14: ffffa3714455fa58 R15: ffff895889550000
[   17.609888] FS:  0000000000000000(0000) GS:ffff896757c00000(0000) knlGS:0000000000000000
[   17.610015] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[   17.610143] CR2: 0000716b8cda2750 CR3: 0000000914e22000 CR4: 0000000000f50ef0
[   17.610272] PKRU: 55555554
[   17.610403] Call Trace:
[   17.610535]  <TASK>
[   17.610662]  ? __die_body.cold+0x19/0x27
[   17.610791]  ? die+0x2e/0x50
[   17.610918]  ? do_trap+0xca/0x110
[   17.611049]  ? do_error_trap+0x6a/0x90
[   17.611178]  ? bch2_lookup_indirect_extent+0x252/0x290 [bcachefs c42b95c23facdfe11d39755520127cd771dddec2]
[   17.611331]  ? exc_invalid_op+0x50/0x70
[   17.611468]  ? bch2_lookup_indirect_extent+0x252/0x290 [bcachefs c42b95c23facdfe11d39755520127cd771dddec2]
[   17.611620]  ? asm_exc_invalid_op+0x1a/0x20
[   17.611757]  ? bch2_lookup_indirect_extent+0x252/0x290 [bcachefs c42b95c23facdfe11d39755520127cd771dddec2]
[   17.611911]  ? bch2_move_data_btree+0x58a/0x6c0 [bcachefs c42b95c23facdfe11d39755520127cd771dddec2]
[   17.612084]  bch2_move_data_btree+0x58a/0x6c0 [bcachefs c42b95c23facdfe11d39755520127cd771dddec2]
[   17.612256]  ? __pfx_rebalance_pred+0x10/0x10 [bcachefs c42b95c23facdfe11d39755520127cd771dddec2]
[   17.612431]  ? bch2_move_extent+0x3d7/0x6e0 [bcachefs c42b95c23facdfe11d39755520127cd771dddec2]
[   17.612607]  ? __bch2_move_data+0xea/0x200 [bcachefs c42b95c23facdfe11d39755520127cd771dddec2]
[   17.612782]  __bch2_move_data+0xea/0x200 [bcachefs c42b95c23facdfe11d39755520127cd771dddec2]
[   17.612959]  ? __pfx_rebalance_pred+0x10/0x10 [bcachefs c42b95c23facdfe11d39755520127cd771dddec2]
[   17.613149]  do_rebalance+0x517/0x8d0 [bcachefs c42b95c23facdfe11d39755520127cd771dddec2]
[   17.613342]  ? local_clock_noinstr+0xd/0xd0
[   17.613518]  ? local_clock+0x15/0x30
[   17.613693]  ? __bch2_trans_get+0x152/0x300 [bcachefs c42b95c23facdfe11d39755520127cd771dddec2]
[   17.613890]  ? __pfx_bch2_rebalance_thread+0x10/0x10 [bcachefs c42b95c23facdfe11d39755520127cd771dddec2]
[   17.614090]  bch2_rebalance_thread+0x66/0xb0 [bcachefs c42b95c23facdfe11d39755520127cd771dddec2]

The offset_into_extent bit was copied from the read path, but it's
unnecessary here, where we always want to read and move the entire
indirect extent, and it causes the assertion pop - because we're using a
non-extents iterator, which always points to the end of the reflink
pointer.

Reported-by: Maël Kerbiriou <mael.kerbiriou@free.fr>
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
2025-03-24 09:50:34 -04:00
Eric Biggers
71fbb0b86e bcachefs: use sha256() instead of crypto_shash API
Just use sha256() instead of the clunky crypto API.  This is much
simpler.

Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
2025-03-24 09:50:34 -04:00
Eric Biggers
39abc73b59 bcachefs: Remove unnecessary softdeps on crc32c and crc64
Since bcachefs does not access crc32c and crc64 through the crypto API,
there is no need to use module softdeps to ensure they are loaded.

Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
2025-03-24 09:50:34 -04:00
Kent Overstreet
9b39835e93 bcachefs: #if 0 out (enable|disable)_encryption()
These weren't hooked up, but they probably should be - add some comments
for context.

Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
2025-03-24 09:50:34 -04:00
Kent Overstreet
9962cb7748 bcachefs: Improve can_write_extent()
This fixes another "rebalance spinning and doing no work" issue;
rebalance was reading extents it wanted to move, but then failing in
bch2_write() -> bch2_alloc_sectors_start() due to being unable to
allocate sufficient replicas.

This was triggered by a user playing with the durability settings, the
foreground device was an NVME device with durability=2, and originally
he'd set the background device to durability=2 as well, but changed it
back to 1 (the default) after seeing IO errors.

That meant that with replicas=2, we want to move data off the NVME
device which satisfies that constraint, but with a single durability=1
device on the background target there's no way to move the extent to
that target while satisfiying the "required replicas" constraint.

The solution for now is for bch2_data_update_init() to check for this,
and return an error - before kicking off the read.

bch2_data_update_init() already had two different checks for "will we be
able to write this extent", with partially duplicated code, so this
patch combines and improves that logic.

Additionally, we now always bail out and return an error if there's
insufficient space on the destination target. Previously, we only did
this for BCH_WRITE_alloc_nowait moves, because it might be the case that
copygc just needs to free up space on the destination target.

But we really shouldn't kick off a move if the destination is full, we
can't currently distinguish between "really full" and "just need to wait
for copygc", and if we are going to wait on copygc it'd be better to do
that before kicking off the move.

This will additionally fix "rebalance spinning" issues caused by a
filesystem that has more data than can fit in background_target - which
is a valid scenario, since we don't exclude foreground/cache devices
when calculating filesystem capacity.

Reported-by: Maël Kerbiriou <mael.kerbiriou@free.fr>
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
2025-03-24 09:50:34 -04:00
Kent Overstreet
fb8a9a32cc bcachefs: trace_io_move_write_fail
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
2025-03-24 09:50:34 -04:00
Alan Huang
76bc6e51cd bcachefs: Increase blacklist range
Now there are 16 journal buffers, 8 is too small to be enough.

Signed-off-by: Alan Huang <mmpgouride@gmail.com>
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
2025-03-24 09:50:34 -04:00
Kent Overstreet
35de2abc22 bcachefs: __bch2_read() now takes a btree_trans
Next patch will be checking if the extent we're reading from matches the
IO failure we saw before marking the failure.

For this to work, __bch2_read() needs to take the same transaction
context that bch2_rbio_retry() uses to do that check.

Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
2025-03-24 09:50:34 -04:00
Kent Overstreet
3fb8bacb14 bcachefs: BCH_READ_data_update -> bch_read_bio.data_update
Read flags are codepath dependent and change as they're passed around,
while the fields in rbio._state are mostly fixed properties of that
particular object.

Losing track of BCH_READ_data_update would be bad, and previously it was
not obvious if it was always correctly set in the rbio, so this is a
safety cleanup.

Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
2025-03-24 09:50:34 -04:00
Kent Overstreet
be31e412ac bcachefs: Checksum errors get additional retries
It's possible for checksum errors to be transient - e.g. flakey
controller or cable, thus we need additional retries (besides retrying
from different replicas) before we can definitely return an error.

This is particularly important for the next patch, which will allow the
data move path to move extents with checksum errors - we don't want to
accidentally introduce bitrot due to a transient error!

- bch2_bkey_pick_read_device() is substantially reworked, and
  bch2_dev_io_failures is expanded to record more information about the
  type of failure (i.e. number of checksum errors).

  It now returns an error code that describes more precisely the reason
  for the failure - checksum error, io error, or offline device, instead
  of the previous generic "insufficient devices". This is important for
  the next patches that add poisoning, as we only want to poison extents
  when we've got real checksum errors (or perhaps IO errors?) - not
  because a device was offline.

- Add a new option and superblock field for the number of checksum
  retries.

Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
2025-03-16 13:47:55 -04:00
Kent Overstreet
ccba9029b0 bcachefs: Print message on successful read retry
Users have been asking for this, and now that errors are returned to the
top level read retry path - we can.

Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
2025-03-16 13:47:55 -04:00
Kent Overstreet
de73677ff8 bcachefs: Return errors to top level bch2_rbio_retry()
Next patch will be adding an additional retry loop for checksum errors,
so that we can rule out transient errors before marking an extent as
poisoned.

Prerequisite to this is returning errors to bch2_rbio_retry(); this will
also let us add a "successful retry" message.

Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
2025-03-16 13:47:55 -04:00
Kent Overstreet
881b598ef1 bcachefs: BCH_ERR_data_read_buffer_too_small
Now that the read path uses proper error codes, we can get rid of the
weird rbio->hole signalling to the move path that the read didn't
happen.

Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
2025-03-16 13:47:55 -04:00
Kent Overstreet
f4b84bac20 bcachefs: Read error message now indicates if it was for an internal move
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
2025-03-16 13:47:55 -04:00
Kent Overstreet
e75993b0bf bcachefs: Fix BCH_ERR_data_read_csum_err_maybe_userspace in retry path
When we do a read to a buffer that's mapped into userspace, it's
possible to get a spurious checksum error if userspace was modified the
buffer at the same time.

When we retry those, they have to be bounced before we know definitively
whether we're reading corrupt data.

But the retry path propagates read flags differently, so needs special
handling.

Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
2025-03-16 13:47:55 -04:00
Kent Overstreet
943f0cfb15 bcachefs: Convert read path to standard error codes
Kill the READ_ERR/READ_RETRY/READ_RETRY_AVOID enums, and add standard
error codes that describe precisely which error occured.

This is going to be used for the data move path, to move but poison
extents with checksum errors.

Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
2025-03-16 13:47:55 -04:00