lwn.git/fs/btrfs, branch v6.11-rc3

Merge tag 'for-6.11-rc2-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux

2024-08-07T16:53:41+00:00

Pull btrfs fixes from David Sterba: - fix double inode unlock for direct IO sync writes (reported by syzbot) - fix root tree id/name map definitions, don't use fixed size buffers for name (reported by -Werror=unterminated-string-initialization) - fix qgroup reserve leaks in bufferd write path - update scrub status structure more often so it can be reported in user space more accurately and let 'resume' not repeat work - in preparation to remove space cache v1 in the future print a warning if it's detected * tag 'for-6.11-rc2-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux: btrfs: avoid using fixed char array size for tree names btrfs: fix double inode unlock for direct IO sync writes btrfs: emit a warning about space cache v1 being deprecated btrfs: fix qgroup reserve leaks in cow_file_range btrfs: implement launder_folio for clearing dirty page reserve btrfs: scrub: update last_physical after scrubbing one stripe btrfs: factor out stripe length calculation into a helper

btrfs: avoid using fixed char array size for tree names

2024-08-02T20:44:27+00:00

[BUG] There is a bug report that using the latest trunk GCC 15, btrfs would cause unterminated-string-initialization warning: linux-6.6/fs/btrfs/print-tree.c:29:49: error: initializer-string for array of ‘char’ is too long [-Werror=unterminated-string-initialization] 29 | { BTRFS_BLOCK_GROUP_TREE_OBJECTID, "BLOCK_GROUP_TREE" }, | ^~~~~~~~~~~~~~~~~~ [CAUSE] To print tree names we have an array of root_name_map structure, which uses "char name[16];" to store the name string of a tree. But the following trees have names exactly at 16 chars length: - "BLOCK_GROUP_TREE" - "RAID_STRIPE_TREE" This means we will have no space for the terminating '\0', and can lead to unexpected access when printing the name. [FIX] Instead of "char name[16];" use "const char *" instead. Since the name strings are all read-only data, and are all NULL terminated by default, there is not much need to bother the length at all. Reported-by: Sam James Reported-by: Alejandro Colomar Fixes: edde81f1abf29 ("btrfs: add raid stripe tree pretty printer") Fixes: 9c54e80ddc6bd ("btrfs: add code to support the block group root") CC: stable@vger.kernel.org # 6.1+ Suggested-by: Alejandro Colomar Reviewed-by: Johannes Thumshirn Reviewed-by: Alejandro Colomar Signed-off-by: Qu Wenruo Reviewed-by: David Sterba Signed-off-by: David Sterba

btrfs: fix double inode unlock for direct IO sync writes

2024-08-02T20:32:40+00:00

If we do a direct IO sync write, at btrfs_sync_file(), and we need to skip inode logging or we get an error starting a transaction or an error when flushing delalloc, we end up unlocking the inode when we shouldn't under the 'out_release_extents' label, and then unlock it again at btrfs_direct_write(). Fix that by checking if we have to skip inode unlocking under that label. Reported-by: syzbot+7dbbb74af6291b5a5a8b@syzkaller.appspotmail.com Link: https://lore.kernel.org/linux-btrfs/000000000000dfd631061eaeb4bc@google.com/ Fixes: 939b656bc8ab ("btrfs: fix corruption after buffer fault in during direct IO append write") Reviewed-by: Josef Bacik Signed-off-by: Filipe Manana Signed-off-by: David Sterba

btrfs: emit a warning about space cache v1 being deprecated

2024-08-01T15:30:50+00:00

We've been wanting to get rid of this for a while, add a message to indicate that this feature is going away and when so we can finally have a date when we're going to remove it. The output looks like this BTRFS warning (device nvme0n1): space cache v1 is being deprecated and will be removed in a future release, please use -o space_cache=v2 Reviewed-by: Qu Wenruo Reviewed-by: Neal Gompa Signed-off-by: Josef Bacik Reviewed-by: David Sterba Signed-off-by: David Sterba

btrfs: fix qgroup reserve leaks in cow_file_range

2024-08-01T15:26:52+00:00

In the buffered write path, the dirty page owns the qgroup reserve until it creates an ordered_extent. Therefore, any errors that occur before the ordered_extent is created must free that reservation, or else the space is leaked. The fstest generic/475 exercises various IO error paths, and is able to trigger errors in cow_file_range where we fail to get to allocating the ordered extent. Note that because we *do* clear delalloc, we are likely to remove the inode from the delalloc list, so the inodes/pages to not have invalidate/launder called on them in the commit abort path. This results in failures at the unmount stage of the test that look like: BTRFS: error (device dm-8 state EA) in cleanup_transaction:2018: errno=-5 IO failure BTRFS: error (device dm-8 state EA) in btrfs_replace_file_extents:2416: errno=-5 IO failure BTRFS warning (device dm-8 state EA): qgroup 0/5 has unreleased space, type 0 rsv 28672 ------------[ cut here ]------------ WARNING: CPU: 3 PID: 22588 at fs/btrfs/disk-io.c:4333 close_ctree+0x222/0x4d0 [btrfs] Modules linked in: btrfs blake2b_generic libcrc32c xor zstd_compress raid6_pq CPU: 3 PID: 22588 Comm: umount Kdump: loaded Tainted: G W 6.10.0-rc7-gab56fde445b8 #21 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS Arch Linux 1.16.3-1-1 04/01/2014 RIP: 0010:close_ctree+0x222/0x4d0 [btrfs] RSP: 0018:ffffb4465283be00 EFLAGS: 00010202 RAX: 0000000000000001 RBX: ffffa1a1818e1000 RCX: 0000000000000001 RDX: 0000000000000000 RSI: ffffb4465283bbe0 RDI: ffffa1a19374fcb8 RBP: ffffa1a1818e13c0 R08: 0000000100028b16 R09: 0000000000000000 R10: 0000000000000003 R11: 0000000000000003 R12: ffffa1a18ad7972c R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000 FS: 00007f9168312b80(0000) GS:ffffa1a4afcc0000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f91683c9140 CR3: 000000010acaa000 CR4: 00000000000006f0 Call Trace: ? close_ctree+0x222/0x4d0 [btrfs] ? __warn.cold+0x8e/0xea ? close_ctree+0x222/0x4d0 [btrfs] ? report_bug+0xff/0x140 ? handle_bug+0x3b/0x70 ? exc_invalid_op+0x17/0x70 ? asm_exc_invalid_op+0x1a/0x20 ? close_ctree+0x222/0x4d0 [btrfs] generic_shutdown_super+0x70/0x160 kill_anon_super+0x11/0x40 btrfs_kill_super+0x11/0x20 [btrfs] deactivate_locked_super+0x2e/0xa0 cleanup_mnt+0xb5/0x150 task_work_run+0x57/0x80 syscall_exit_to_user_mode+0x121/0x130 do_syscall_64+0xab/0x1a0 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f916847a887 ---[ end trace 0000000000000000 ]--- BTRFS error (device dm-8 state EA): qgroup reserved space leaked Cases 2 and 3 in the out_reserve path both pertain to this type of leak and must free the reserved qgroup data. Because it is already an error path, I opted not to handle the possible errors in btrfs_free_qgroup_data. Reviewed-by: Qu Wenruo Signed-off-by: Boris Burkov Signed-off-by: David Sterba

btrfs: implement launder_folio for clearing dirty page reserve

2024-08-01T15:26:40+00:00

In the buffered write path, dirty pages can be said to "own" the qgroup reservation until they create an ordered_extent. It is possible for there to be outstanding dirty pages when a transaction is aborted, in which case there is no cancellation path for freeing this reservation and it is leaked. We do already walk the list of outstanding delalloc inodes in btrfs_destroy_delalloc_inodes() and call invalidate_inode_pages2() on them. This does *not* call btrfs_invalidate_folio(), as one might guess, but rather calls launder_folio() and release_folio(). Since this is a reservation associated with dirty pages only, rather than something associated with the private bit (ordered_extent is cancelled separately already in the cleanup transaction path), implementing this release should be done via launder_folio. Reviewed-by: Qu Wenruo Signed-off-by: Boris Burkov Signed-off-by: David Sterba

btrfs: scrub: update last_physical after scrubbing one stripe

2024-08-01T15:15:07+00:00

Currently sctx->stat.last_physical only got updated in the following cases: - When the last stripe of a non-RAID56 chunk is scrubbed This implies a pitfall, if the last stripe is at the chunk boundary, and we finished the scrub of the whole chunk, we won't update last_physical at all until the next chunk. - When a P/Q stripe of a RAID56 chunk is scrubbed This leads the following two problems: - sctx->stat.last_physical is not updated for a almost full chunk This is especially bad, affecting scrub resume, as the resume would start from last_physical, causing unnecessary re-scrub. - "btrfs scrub status" will not report any progress for a long time Fix the problem by properly updating @last_physical after each stripe is scrubbed. And since we're here, for the sake of consistency, use spin lock to protect the update of @last_physical, just like all the remaining call sites touching sctx->stat. Reported-by: Michel Palleau Link: https://lore.kernel.org/linux-btrfs/CAMFk-+igFTv2E8svg=cQ6o3e6CrR5QwgQ3Ok9EyRaEvvthpqCQ@mail.gmail.com/ Reviewed-by: Johannes Thumshirn Signed-off-by: Qu Wenruo Reviewed-by: David Sterba Signed-off-by: David Sterba

btrfs: factor out stripe length calculation into a helper

2024-08-01T15:15:05+00:00

Currently there are two locations which need to calculate the real length of a stripe (which can be at the end of a chunk, and the chunk size may not always be 64K aligned). Factor them into a helper as we're going to have a third user soon. Reviewed-by: Johannes Thumshirn Signed-off-by: Qu Wenruo Reviewed-by: David Sterba Signed-off-by: David Sterba

Merge tag 'for-6.11-rc1-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux

2024-07-31T02:28:36+00:00

Pull btrfs fixes from David Sterba: - fix regression in extent map rework when handling insertion of overlapping compressed extent - fix unexpected file length when appending to a file using direct io and buffer not faulted in - in zoned mode, fix accounting of unusable space when flipping read-only block group back to read-write - fix page locking when COWing an inline range, assertion failure found by syzbot - fix calculation of space info in debugging print - tree-checker, add validation of data reference item - fix a few -Wmaybe-uninitialized build warnings * tag 'for-6.11-rc1-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux: btrfs: initialize location to fix -Wmaybe-uninitialized in btrfs_lookup_dentry() btrfs: fix corruption after buffer fault in during direct IO append write btrfs: zoned: fix zone_unusable accounting on making block group read-write again btrfs: do not subtract delalloc from avail bytes btrfs: make cow_file_range_inline() honor locked_page on error btrfs: fix corrupt read due to bad offset of a compressed extent map btrfs: tree-checker: validate dref root and objectid

btrfs: initialize location to fix -Wmaybe-uninitialized in btrfs_lookup_dentry()

2024-07-30T13:33:06+00:00

Some arch + compiler combinations report a potentially unused variable location in btrfs_lookup_dentry(). This is a false alert as the variable is passed by value and always valid or there's an error. The compilers cannot probably reason about that although btrfs_inode_by_name() is in the same file. > + /kisskb/src/fs/btrfs/inode.c: error: 'location.objectid' may be used +uninitialized in this function [-Werror=maybe-uninitialized]: => 5603:9 > + /kisskb/src/fs/btrfs/inode.c: error: 'location.type' may be used +uninitialized in this function [-Werror=maybe-uninitialized]: => 5674:5 m68k-gcc8/m68k-allmodconfig mips-gcc8/mips-allmodconfig powerpc-gcc5/powerpc-all{mod,yes}config powerpc-gcc5/ppc64_defconfig Initialize it to zero, this should fix the warnings and won't change the behaviour as btrfs_inode_by_name() accepts only a root or inode item types, otherwise returns an error. Reported-by: Geert Uytterhoeven Tested-by: Geert Uytterhoeven Link: https://lore.kernel.org/linux-btrfs/bd4e9928-17b3-9257-8ba7-6b7f9bbb639a@linux-m68k.org/ Reviewed-by: Qu Wenruo Signed-off-by: David Sterba