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2026-03-04btrfs: continue trimming remaining devices on failurejinbaohong1-1/+1
[ Upstream commit 912d1c6680bdb40b72b1b9204706f32b6eb842c3 ] Commit 93bba24d4b5a ("btrfs: Enhance btrfs_trim_fs function to handle error better") intended to make device trimming continue even if one device fails, tracking failures and reporting them at the end. However, it used 'break' instead of 'continue', causing the loop to exit on the first device failure. Fix this by replacing 'break' with 'continue'. Fixes: 93bba24d4b5a ("btrfs: Enhance btrfs_trim_fs function to handle error better") CC: stable@vger.kernel.org # 5.4+ Reviewed-by: Qu Wenruo <wqu@suse.com> Signed-off-by: Robbie Ko <robbieko@synology.com> Signed-off-by: jinbaohong <jinbaohong@synology.com> Reviewed-by: Filipe Manana <fdmanana@suse.com> Signed-off-by: Filipe Manana <fdmanana@suse.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
2026-03-04btrfs: replace BUG() with error handling in __btrfs_balance()Adarsh Das1-2/+8
[ Upstream commit be6324a809dbda76d5fdb23720ad9b20e5c1905c ] We search with offset (u64)-1 which should never match exactly. Previously this was handled with BUG(). Now logs an error and return -EUCLEAN. Reviewed-by: Qu Wenruo <wqu@suse.com> Signed-off-by: Adarsh Das <adarshdas950@gmail.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
2026-03-04btrfs: handle user interrupt properly in btrfs_trim_fs()jinbaohong1-0/+11
[ Upstream commit bfb670b9183b0e4ba660aff2e396ec1cc01d0761 ] When a fatal signal is pending or the process is freezing, btrfs_trim_block_group() and btrfs_trim_free_extents() return -ERESTARTSYS. Currently this is treated as a regular error: the loops continue to the next iteration and count it as a block group or device failure. Instead, break out of the loops immediately and return -ERESTARTSYS to userspace without counting it as a failure. Also skip the device loop entirely if the block group loop was interrupted. Reviewed-by: Qu Wenruo <wqu@suse.com> Signed-off-by: Robbie Ko <robbieko@synology.com> Signed-off-by: jinbaohong <jinbaohong@synology.com> Reviewed-by: Filipe Manana <fdmanana@suse.com> Signed-off-by: Filipe Manana <fdmanana@suse.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
2026-03-04btrfs: fix invalid leaf access in btrfs_quota_enable() if ref key not foundFilipe Manana1-4/+7
[ Upstream commit ecb7c2484cfc83a93658907580035a8adf1e0a92 ] If btrfs_search_slot_for_read() returns 1, it means we did not find any key greater than or equals to the key we asked for, meaning we have reached the end of the tree and therefore the path is not valid. If this happens we need to break out of the loop and stop, instead of continuing and accessing an invalid path. Fixes: 5223cc60b40a ("btrfs: drop the path before adding qgroup items when enabling qgroups") Reviewed-by: Qu Wenruo <wqu@suse.com> Signed-off-by: Filipe Manana <fdmanana@suse.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
2026-03-04btrfs: fix block_group_tree dirty_list corruptionBoris Burkov1-7/+0
[ Upstream commit 3a1f4264daed4b419c325a7fe35e756cada3cf82 ] When the incompat flag EXTENT_TREE_V2 is set, we unconditionally add the block group tree to the switch_commits list before calling switch_commit_roots, as we do for the tree root and the chunk root. However, the block group tree uses normal root dirty tracking and in any transaction that does an allocation and dirties a block group, the block group root will already be linked to a list by the dirty_list field and this use of list_add_tail() is invalid and corrupts the prev/next members of block_group_root->dirty_list. This is apparent on a subsequent list_del on the prev if we enable CONFIG_DEBUG_LIST: [32.1571] ------------[ cut here ]------------ [32.1572] list_del corruption. next->prev should beffff958890202538, but was ffff9588992bd538. (next=ffff958890201538) [32.1575] WARNING: lib/list_debug.c:65 at 0x0, CPU#3: sync/607 [32.1583] CPU: 3 UID: 0 PID: 607 Comm: sync Not tainted 6.18.0 #24PREEMPT(none) [32.1585] Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS1.17.0-4.fc41 04/01/2014 [32.1587] RIP: 0010:__list_del_entry_valid_or_report+0x108/0x120 [32.1593] RSP: 0018:ffffaa288287fdd0 EFLAGS: 00010202 [32.1594] RAX: 0000000000000001 RBX: ffff95889326e800 RCX:ffff958890201538 [32.1596] RDX: ffff9588992bd538 RSI: ffff958890202538 RDI:ffffffff82a41e00 [32.1597] RBP: ffff958890202538 R08: ffffffff828fc1e8 R09:00000000ffffefff [32.1599] R10: ffffffff8288c200 R11: ffffffff828e4200 R12:ffff958890201538 [32.1601] R13: ffff95889326e958 R14: ffff958895c24000 R15:ffff958890202538 [32.1603] FS: 00007f0c28eb5740(0000) GS:ffff958af2bd2000(0000)knlGS:0000000000000000 [32.1605] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [32.1607] CR2: 00007f0c28e8a3cc CR3: 0000000109942005 CR4:0000000000370ef0 [32.1609] Call Trace: [32.1610] <TASK> [32.1611] switch_commit_roots+0x82/0x1d0 [btrfs] [32.1615] btrfs_commit_transaction+0x968/0x1550 [btrfs] [32.1618] ? btrfs_attach_transaction_barrier+0x23/0x60 [btrfs] [32.1621] __iterate_supers+0xe8/0x190 [32.1622] ? __pfx_sync_fs_one_sb+0x10/0x10 [32.1623] ksys_sync+0x63/0xb0 [32.1624] __do_sys_sync+0xe/0x20 [32.1625] do_syscall_64+0x73/0x450 [32.1626] entry_SYSCALL_64_after_hwframe+0x76/0x7e [32.1627] RIP: 0033:0x7f0c28d05d2b [32.1632] RSP: 002b:00007ffc9d988048 EFLAGS: 00000246 ORIG_RAX:00000000000000a2 [32.1634] RAX: ffffffffffffffda RBX: 00007ffc9d988228 RCX:00007f0c28d05d2b [32.1636] RDX: 00007f0c28e02301 RSI: 00007ffc9d989b21 RDI:00007f0c28dba90d [32.1637] RBP: 0000000000000001 R08: 0000000000000001 R09:0000000000000000 [32.1639] R10: 0000000000000000 R11: 0000000000000246 R12:000055b96572cb80 [32.1641] R13: 000055b96572b19f R14: 00007f0c28dfa434 R15:000055b96572b034 [32.1643] </TASK> [32.1644] irq event stamp: 0 [32.1644] hardirqs last enabled at (0): [<0000000000000000>] 0x0 [32.1646] hardirqs last disabled at (0): [<ffffffff81298817>]copy_process+0xb37/0x2260 [32.1648] softirqs last enabled at (0): [<ffffffff81298817>]copy_process+0xb37/0x2260 [32.1650] softirqs last disabled at (0): [<0000000000000000>] 0x0 [32.1652] ---[ end trace 0000000000000000 ]--- Furthermore, this list corruption eventually (when we happen to add a new block group) results in getting the switch_commits and dirty_cowonly_roots lists mixed up and attempting to call update_root on the tree root which can't be found in the tree root, resulting in a transaction abort: [87.8269] BTRFS critical (device nvme1n1): unable to find root key (1 0 0) in tree 1 [87.8272] ------------[ cut here ]------------ [87.8274] BTRFS: Transaction aborted (error -117) [87.8275] WARNING: fs/btrfs/root-tree.c:153 at 0x0, CPU#4: sync/703 [87.8285] CPU: 4 UID: 0 PID: 703 Comm: sync Not tainted 6.18.0 #25 PREEMPT(none) [87.8287] Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.17.0-4.fc41 04/01/2014 [87.8289] RIP: 0010:btrfs_update_root+0x296/0x790 [btrfs] [87.8295] RSP: 0018:ffffa58d035dfd60 EFLAGS: 00010282 [87.8297] RAX: ffff9a59126ddb68 RBX: ffff9a59126dc000 RCX: 0000000000000000 [87.8299] RDX: 0000000000000000 RSI: 00000000ffffff8b RDI: ffffffffc0b28270 [87.8301] RBP: ffff9a5904aec000 R08: 0000000000000000 R09: 00000000ffffefff [87.8303] R10: ffffffff9ac8c200 R11: ffffffff9ace4200 R12: 0000000000000001 [87.8305] R13: ffff9a59041740e8 R14: ffff9a5904aec1f7 R15: ffff9a590fdefaf0 [87.8307] FS: 00007f54cde6b740(0000) GS:ffff9a5b5a81c000(0000) knlGS:0000000000000000 [87.8309] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [87.8310] CR2: 00007f54cde403cc CR3: 0000000112902004 CR4: 0000000000370ef0 [87.8312] Call Trace: [87.8313] <TASK> [87.8314] ? _raw_spin_unlock+0x23/0x40 [87.8315] commit_cowonly_roots+0x1ad/0x250 [btrfs] [87.8317] ? btrfs_commit_transaction+0x79b/0x1560 [btrfs] [87.8320] btrfs_commit_transaction+0x8aa/0x1560 [btrfs] [87.8322] ? btrfs_attach_transaction_barrier+0x23/0x60 [btrfs] [87.8325] __iterate_supers+0xf1/0x170 [87.8326] ? __pfx_sync_fs_one_sb+0x10/0x10 [87.8327] ksys_sync+0x63/0xb0 [87.8328] __do_sys_sync+0xe/0x20 [87.8329] do_syscall_64+0x73/0x450 [87.8330] entry_SYSCALL_64_after_hwframe+0x76/0x7e [87.8331] RIP: 0033:0x7f54cdd05d2b [87.8336] RSP: 002b:00007fff1b58ff78 EFLAGS: 00000246 ORIG_RAX: 00000000000000a2 [87.8338] RAX: ffffffffffffffda RBX: 00007fff1b590158 RCX: 00007f54cdd05d2b [87.8340] RDX: 00007f54cde02301 RSI: 00007fff1b592b66 RDI: 00007f54cddba90d [87.8342] RBP: 0000000000000001 R08: 0000000000000001 R09: 0000000000000000 [87.8344] R10: 0000000000000000 R11: 0000000000000246 R12: 000055e07ca96b80 [87.8346] R13: 000055e07ca9519f R14: 00007f54cddfa434 R15: 000055e07ca95034 [87.8348] </TASK> [87.8348] irq event stamp: 0 [87.8349] hardirqs last enabled at (0): [<0000000000000000>] 0x0 [87.8351] hardirqs last disabled at (0): [<ffffffff99698797>] copy_process+0xb37/0x21e0 [87.8353] softirqs last enabled at (0): [<ffffffff99698797>] copy_process+0xb37/0x21e0 [87.8355] softirqs last disabled at (0): [<0000000000000000>] 0x0 [87.8357] ---[ end trace 0000000000000000 ]--- [87.8358] BTRFS: error (device nvme1n1 state A) in btrfs_update_root:153: errno=-117 Filesystem corrupted [87.8360] BTRFS info (device nvme1n1 state EA): forced readonly [87.8362] BTRFS warning (device nvme1n1 state EA): Skipping commit of aborted transaction. [87.8364] BTRFS: error (device nvme1n1 state EA) in cleanup_transaction:2037: errno=-117 Filesystem corrupted Since the block group tree was pulled out of the extent tree and uses normal root dirty tracking, remove the offending extra list_add. This fixes the list corruption and the resulting fs corruption. Fixes: 14033b08a029 ("btrfs: don't save block group root into super block") Reviewed-by: Filipe Manana <fdmanana@suse.com> Signed-off-by: Boris Burkov <boris@bur.io> Signed-off-by: David Sterba <dsterba@suse.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
2026-03-04btrfs: qgroup: return correct error when deleting qgroup relation itemFilipe Manana1-1/+3
[ Upstream commit 51b1fcf71c88c3c89e7dcf07869c5de837b1f428 ] If we fail to delete the second qgroup relation item, we end up returning success or -ENOENT in case the first item does not exist, instead of returning the error from the second item deletion. Fixes: 73798c465b66 ("btrfs: qgroup: Try our best to delete qgroup relations") Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com> Signed-off-by: Filipe Manana <fdmanana@suse.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
2026-02-11btrfs: fix racy bitfield write in btrfs_clear_space_info_full()Boris Burkov3-17/+17
commit 38e818718c5e04961eea0fa8feff3f100ce40408 upstream. From the memory-barriers.txt document regarding memory barrier ordering guarantees: (*) These guarantees do not apply to bitfields, because compilers often generate code to modify these using non-atomic read-modify-write sequences. Do not attempt to use bitfields to synchronize parallel algorithms. (*) Even in cases where bitfields are protected by locks, all fields in a given bitfield must be protected by one lock. If two fields in a given bitfield are protected by different locks, the compiler's non-atomic read-modify-write sequences can cause an update to one field to corrupt the value of an adjacent field. btrfs_space_info has a bitfield sharing an underlying word consisting of the fields full, chunk_alloc, and flush: struct btrfs_space_info { struct btrfs_fs_info * fs_info; /* 0 8 */ struct btrfs_space_info * parent; /* 8 8 */ ... int clamp; /* 172 4 */ unsigned int full:1; /* 176: 0 4 */ unsigned int chunk_alloc:1; /* 176: 1 4 */ unsigned int flush:1; /* 176: 2 4 */ ... Therefore, to be safe from parallel read-modify-writes losing a write to one of the bitfield members protected by a lock, all writes to all the bitfields must use the lock. They almost universally do, except for btrfs_clear_space_info_full() which iterates over the space_infos and writes out found->full = 0 without a lock. Imagine that we have one thread completing a transaction in which we finished deleting a block_group and are thus calling btrfs_clear_space_info_full() while simultaneously the data reclaim ticket infrastructure is running do_async_reclaim_data_space(): T1 T2 btrfs_commit_transaction btrfs_clear_space_info_full data_sinfo->full = 0 READ: full:0, chunk_alloc:0, flush:1 do_async_reclaim_data_space(data_sinfo) spin_lock(&space_info->lock); if(list_empty(tickets)) space_info->flush = 0; READ: full: 0, chunk_alloc:0, flush:1 MOD/WRITE: full: 0, chunk_alloc:0, flush:0 spin_unlock(&space_info->lock); return; MOD/WRITE: full:0, chunk_alloc:0, flush:1 and now data_sinfo->flush is 1 but the reclaim worker has exited. This breaks the invariant that flush is 0 iff there is no work queued or running. Once this invariant is violated, future allocations that go into __reserve_bytes() will add tickets to space_info->tickets but will see space_info->flush is set to 1 and not queue the work. After this, they will block forever on the resulting ticket, as it is now impossible to kick the worker again. I also confirmed by looking at the assembly of the affected kernel that it is doing RMW operations. For example, to set the flush (3rd) bit to 0, the assembly is: andb $0xfb,0x60(%rbx) and similarly for setting the full (1st) bit to 0: andb $0xfe,-0x20(%rax) So I think this is really a bug on practical systems. I have observed a number of systems in this exact state, but am currently unable to reproduce it. Rather than leaving this footgun lying around for the future, take advantage of the fact that there is room in the struct anyway, and that it is already quite large and simply change the three bitfield members to bools. This avoids writes to space_info->full having any effect on writes to space_info->flush, regardless of locking. Fixes: 957780eb2788 ("Btrfs: introduce ticketed enospc infrastructure") Reviewed-by: Qu Wenruo <wqu@suse.com> Signed-off-by: Boris Burkov <boris@bur.io> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com> [ The context change is due to the commit cc0517fe779f ("btrfs: tweak extent/chunk allocation for space_info sub-space") in v6.16 which is irrelevant to the logic of this patch. ] Signed-off-by: Rahul Sharma <black.hawk@163.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2026-02-11btrfs: fix reservation leak in some error paths when inserting inline extentFilipe Manana1-6/+10
[ Upstream commit c1c050f92d8f6aac4e17f7f2230160794fceef0c ] If we fail to allocate a path or join a transaction, we return from __cow_file_range_inline() without freeing the reserved qgroup data, resulting in a leak. Fix this by ensuring we call btrfs_qgroup_free_data() in such cases. Signed-off-by: Filipe Manana <fdmanana@suse.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
2026-02-06btrfs: prevent use-after-free on page private data in ↵JP Kobryn1-0/+13
btrfs_subpage_clear_uptodate() This is a stable-only patch. The issue was inadvertently fixed in 6.17 [0] as part of a refactoring, but this patch serves as a minimal targeted fix for prior kernels. Users of find_lock_page() need to guard against the situation where releasepage() has been invoked during reclaim but the page was ultimately not removed from the page cache. This patch covers one location that was overlooked. After acquiring the page, use set_page_extent_mapped() to ensure the page private state is valid. This is especially important in the subpage case, where the private field is an allocated struct containing bitmap and lock data. Without this protection, the race below is possible: [mm] page cache reclaim path [fs] relocation in subpage mode shrink_page_list() trylock_page() /* lock acquired */ try_to_release_page() mapping->a_ops->releasepage() btrfs_releasepage() __btrfs_releasepage() clear_page_extent_mapped() btrfs_detach_subpage() subpage = detach_page_private(page) btrfs_free_subpage(subpage) kfree(subpage) /* point A */ prealloc_file_extent_cluster() find_lock_page() page_cache_get_speculative() lock_page() /* wait for lock */ if (...) ... else if (!mapping || !__remove_mapping(..)) /* * __remove_mapping() returns zero when * page_ref_freeze(page, refcount) fails /* point B */ */ goto keep_locked /* page remains in cache */ keep_locked: unlock_page(page) /* lock released */ /* lock acquired */ btrfs_subpage_clear_uptodate() /* use-after-free */ subpage = page->private [0] 4e346baee95f ("btrfs: reloc: unconditionally invalidate the page cache for each cluster") Fixes: 9d9ea1e68a05 ("btrfs: subpage: fix relocation potentially overwriting last page data") Cc: stable@vger.kernel.org # 5.15 - 6.9 Signed-off-by: JP Kobryn <inwardvessel@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2026-01-30btrfs: fix missing fields in superblock backup with BLOCK_GROUP_TREEMark Harmstone1-1/+1
[ Upstream commit 1d8f69f453c2e8a2d99b158e58e02ed65031fa6d ] When the BLOCK_GROUP_TREE compat_ro flag is set, the extent root and csum root fields are getting missed. This is because EXTENT_TREE_V2 treated these differently, and when they were split off this special-casing was mistakenly assigned to BGT rather than the rump EXTENT_TREE_V2. There's no reason why the existence of the block group tree should mean that we don't record the details of the last commit's extent root and csum root. Fix the code in backup_super_roots() so that the correct check gets made. Fixes: 1c56ab991903 ("btrfs: separate BLOCK_GROUP_TREE compat RO flag from EXTENT_TREE_V2") Reviewed-by: Qu Wenruo <wqu@suse.com> Signed-off-by: Mark Harmstone <mark@harmstone.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
2026-01-30btrfs: fix deadlock in wait_current_trans() due to ignored transaction typeRobbie Ko1-5/+6
commit 5037b342825df7094a4906d1e2a9674baab50cb2 upstream. When wait_current_trans() is called during start_transaction(), it currently waits for a blocked transaction without considering whether the given transaction type actually needs to wait for that particular transaction state. The btrfs_blocked_trans_types[] array already defines which transaction types should wait for which transaction states, but this check was missing in wait_current_trans(). This can lead to a deadlock scenario involving two transactions and pending ordered extents: 1. Transaction A is in TRANS_STATE_COMMIT_DOING state 2. A worker processing an ordered extent calls start_transaction() with TRANS_JOIN 3. join_transaction() returns -EBUSY because Transaction A is in TRANS_STATE_COMMIT_DOING 4. Transaction A moves to TRANS_STATE_UNBLOCKED and completes 5. A new Transaction B is created (TRANS_STATE_RUNNING) 6. The ordered extent from step 2 is added to Transaction B's pending ordered extents 7. Transaction B immediately starts commit by another task and enters TRANS_STATE_COMMIT_START 8. The worker finally reaches wait_current_trans(), sees Transaction B in TRANS_STATE_COMMIT_START (a blocked state), and waits unconditionally 9. However, TRANS_JOIN should NOT wait for TRANS_STATE_COMMIT_START according to btrfs_blocked_trans_types[] 10. Transaction B is waiting for pending ordered extents to complete 11. Deadlock: Transaction B waits for ordered extent, ordered extent waits for Transaction B This can be illustrated by the following call stacks: CPU0 CPU1 btrfs_finish_ordered_io() start_transaction(TRANS_JOIN) join_transaction() # -EBUSY (Transaction A is # TRANS_STATE_COMMIT_DOING) # Transaction A completes # Transaction B created # ordered extent added to # Transaction B's pending list btrfs_commit_transaction() # Transaction B enters # TRANS_STATE_COMMIT_START # waiting for pending ordered # extents wait_current_trans() # waits for Transaction B # (should not wait!) Task bstore_kv_sync in btrfs_commit_transaction waiting for ordered extents: __schedule+0x2e7/0x8a0 schedule+0x64/0xe0 btrfs_commit_transaction+0xbf7/0xda0 [btrfs] btrfs_sync_file+0x342/0x4d0 [btrfs] __x64_sys_fdatasync+0x4b/0x80 do_syscall_64+0x33/0x40 entry_SYSCALL_64_after_hwframe+0x44/0xa9 Task kworker in wait_current_trans waiting for transaction commit: Workqueue: btrfs-syno_nocow btrfs_work_helper [btrfs] __schedule+0x2e7/0x8a0 schedule+0x64/0xe0 wait_current_trans+0xb0/0x110 [btrfs] start_transaction+0x346/0x5b0 [btrfs] btrfs_finish_ordered_io.isra.0+0x49b/0x9c0 [btrfs] btrfs_work_helper+0xe8/0x350 [btrfs] process_one_work+0x1d3/0x3c0 worker_thread+0x4d/0x3e0 kthread+0x12d/0x150 ret_from_fork+0x1f/0x30 Fix this by passing the transaction type to wait_current_trans() and checking btrfs_blocked_trans_types[cur_trans->state] against the given type before deciding to wait. This ensures that transaction types which are allowed to join during certain blocked states will not unnecessarily wait and cause deadlocks. Reviewed-by: Filipe Manana <fdmanana@suse.com> Signed-off-by: Robbie Ko <robbieko@synology.com> Signed-off-by: Filipe Manana <fdmanana@suse.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com> Cc: Motiejus Jakštys <motiejus@jakstys.lt> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2026-01-30btrfs: fix memory leaks in create_space_info() error pathsJiasheng Jiang1-2/+6
[ Upstream commit a11224a016d6d1d46a4d9b6573244448a80d4d7f ] In create_space_info(), the 'space_info' object is allocated at the beginning of the function. However, there are two error paths where the function returns an error code without freeing the allocated memory: 1. When create_space_info_sub_group() fails in zoned mode. 2. When btrfs_sysfs_add_space_info_type() fails. In both cases, 'space_info' has not yet been added to the fs_info->space_info list, resulting in a memory leak. Fix this by adding an error handling label to kfree(space_info) before returning. Fixes: 2be12ef79fe9 ("btrfs: Separate space_info create/update") Reviewed-by: Qu Wenruo <wqu@suse.com> Signed-off-by: Jiasheng Jiang <jiashengjiangcool@gmail.com> Signed-off-by: David Sterba <dsterba@suse.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
2026-01-30btrfs: introduce btrfs_space_info sub-groupNaohiro Aota4-6/+76
[ Upstream commit f92ee31e031c7819126d2febdda0c3e91f5d2eb9 ] Current code assumes we have only one space_info for each block group type (DATA, METADATA, and SYSTEM). We sometime need multiple space infos to manage special block groups. One example is handling the data relocation block group for the zoned mode. That block group is dedicated for writing relocated data and we cannot allocate any regular extent from that block group, which is implemented in the zoned extent allocator. This block group still belongs to the normal data space_info. So, when all the normal data block groups are full and there is some free space in the dedicated block group, the space_info looks to have some free space, while it cannot allocate normal extent anymore. That results in a strange ENOSPC error. We need to have a space_info for the relocation data block group to represent the situation properly. Adds a basic infrastructure for having a "sub-group" of a space_info: creation and removing. A sub-group space_info belongs to one of the primary space_infos and has the same flags as its parent. This commit first introduces the relocation data sub-space_info, and the next commit will introduce tree-log sub-space_info. In the future, it could be useful to implement tiered storage for btrfs e.g. by implementing a sub-group space_info for block groups resides on a fast storage. Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com> Signed-off-by: Naohiro Aota <naohiro.aota@wdc.com> Signed-off-by: David Sterba <dsterba@suse.com> Stable-dep-of: a11224a016d6 ("btrfs: fix memory leaks in create_space_info() error paths") Signed-off-by: Sasha Levin <sashal@kernel.org>
2026-01-30btrfs: factor out check_removing_space_info() from btrfs_free_block_groups()Naohiro Aota1-22/+27
[ Upstream commit 1cfdbe0d53b27b4b4a4f4cf2a4e430bc65ba2ba5 ] Factor out check_removing_space_info() from btrfs_free_block_groups(). It sanity checks a to-be-removed space_info. There is no functional change. Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com> Signed-off-by: Naohiro Aota <naohiro.aota@wdc.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com> Stable-dep-of: a11224a016d6 ("btrfs: fix memory leaks in create_space_info() error paths") Signed-off-by: Sasha Levin <sashal@kernel.org>
2026-01-30btrfs: factor out init_space_info() from create_space_info()Naohiro Aota1-11/+16
[ Upstream commit ac5578fef380e68e539a2238ba63dd978a450ef2 ] Factor out initialization of the space_info struct, which is used in a later patch. There is no functional change. Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com> Signed-off-by: Naohiro Aota <naohiro.aota@wdc.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com> Stable-dep-of: a11224a016d6 ("btrfs: fix memory leaks in create_space_info() error paths") Signed-off-by: Sasha Levin <sashal@kernel.org>
2026-01-30btrfs: store fs_info in space_infoBoris Burkov2-0/+2
[ Upstream commit 42f620aec182f62ee72e3fce41cb3353951b3508 ] This is handy when computing space_info dynamic reclaim thresholds where we do not have access to a block group. We could add it to the various functions as a parameter, but it seems reasonable for space_info to have an fs_info pointer. Reviewed-by: Josef Bacik <josef@toxicpanda.com> Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com> Signed-off-by: Boris Burkov <boris@bur.io> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com> Stable-dep-of: a11224a016d6 ("btrfs: fix memory leaks in create_space_info() error paths") Signed-off-by: Sasha Levin <sashal@kernel.org>
2026-01-30btrfs: send: check for inline extents in range_is_hole_in_parent()Qu Wenruo1-0/+2
[ Upstream commit 08b096c1372cd69627f4f559fb47c9fb67a52b39 ] Before accessing the disk_bytenr field of a file extent item we need to check if we are dealing with an inline extent. This is because for inline extents their data starts at the offset of the disk_bytenr field. So accessing the disk_bytenr means we are accessing inline data or in case the inline data is less than 8 bytes we can actually cause an invalid memory access if this inline extent item is the first item in the leaf or access metadata from other items. Fixes: 82bfb2e7b645 ("Btrfs: incremental send, fix unnecessary hole writes for sparse files") Reviewed-by: Filipe Manana <fdmanana@suse.com> Signed-off-by: Qu Wenruo <wqu@suse.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
2026-01-17btrfs: always detect conflicting inodes when logging inode refsFilipe Manana1-4/+2
commit 7ba0b6461bc4edb3005ea6e00cdae189bcf908a5 upstream. After rename exchanging (either with the rename exchange operation or regular renames in multiple non-atomic steps) two inodes and at least one of them is a directory, we can end up with a log tree that contains only of the inodes and after a power failure that can result in an attempt to delete the other inode when it should not because it was not deleted before the power failure. In some case that delete attempt fails when the target inode is a directory that contains a subvolume inside it, since the log replay code is not prepared to deal with directory entries that point to root items (only inode items). 1) We have directories "dir1" (inode A) and "dir2" (inode B) under the same parent directory; 2) We have a file (inode C) under directory "dir1" (inode A); 3) We have a subvolume inside directory "dir2" (inode B); 4) All these inodes were persisted in a past transaction and we are currently at transaction N; 5) We rename the file (inode C), so at btrfs_log_new_name() we update inode C's last_unlink_trans to N; 6) We get a rename exchange for "dir1" (inode A) and "dir2" (inode B), so after the exchange "dir1" is inode B and "dir2" is inode A. During the rename exchange we call btrfs_log_new_name() for inodes A and B, but because they are directories, we don't update their last_unlink_trans to N; 7) An fsync against the file (inode C) is done, and because its inode has a last_unlink_trans with a value of N we log its parent directory (inode A) (through btrfs_log_all_parents(), called from btrfs_log_inode_parent()). 8) So we end up with inode B not logged, which now has the old name of inode A. At copy_inode_items_to_log(), when logging inode A, we did not check if we had any conflicting inode to log because inode A has a generation lower than the current transaction (created in a past transaction); 9) After a power failure, when replaying the log tree, since we find that inode A has a new name that conflicts with the name of inode B in the fs tree, we attempt to delete inode B... this is wrong since that directory was never deleted before the power failure, and because there is a subvolume inside that directory, attempting to delete it will fail since replay_dir_deletes() and btrfs_unlink_inode() are not prepared to deal with dir items that point to roots instead of inodes. When that happens the mount fails and we get a stack trace like the following: [87.2314] BTRFS info (device dm-0): start tree-log replay [87.2318] BTRFS critical (device dm-0): failed to delete reference to subvol, root 5 inode 256 parent 259 [87.2332] ------------[ cut here ]------------ [87.2338] BTRFS: Transaction aborted (error -2) [87.2346] WARNING: CPU: 1 PID: 638968 at fs/btrfs/inode.c:4345 __btrfs_unlink_inode+0x416/0x440 [btrfs] [87.2368] Modules linked in: btrfs loop dm_thin_pool (...) [87.2470] CPU: 1 UID: 0 PID: 638968 Comm: mount Tainted: G W 6.18.0-rc7-btrfs-next-218+ #2 PREEMPT(full) [87.2489] Tainted: [W]=WARN [87.2494] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.16.2-0-gea1b7a073390-prebuilt.qemu.org 04/01/2014 [87.2514] RIP: 0010:__btrfs_unlink_inode+0x416/0x440 [btrfs] [87.2538] Code: c0 89 04 24 (...) [87.2568] RSP: 0018:ffffc0e741f4b9b8 EFLAGS: 00010286 [87.2574] RAX: 0000000000000000 RBX: ffff9d3ec8a6cf60 RCX: 0000000000000000 [87.2582] RDX: 0000000000000002 RSI: ffffffff84ab45a1 RDI: 00000000ffffffff [87.2591] RBP: ffff9d3ec8a6ef20 R08: 0000000000000000 R09: ffffc0e741f4b840 [87.2599] R10: ffff9d45dc1fffa8 R11: 0000000000000003 R12: ffff9d3ee26d77e0 [87.2608] R13: ffffc0e741f4ba98 R14: ffff9d4458040800 R15: ffff9d44b6b7ca10 [87.2618] FS: 00007f7b9603a840(0000) GS:ffff9d4658982000(0000) knlGS:0000000000000000 [87.2629] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [87.2637] CR2: 00007ffc9ec33b98 CR3: 000000011273e003 CR4: 0000000000370ef0 [87.2648] Call Trace: [87.2651] <TASK> [87.2654] btrfs_unlink_inode+0x15/0x40 [btrfs] [87.2661] unlink_inode_for_log_replay+0x27/0xf0 [btrfs] [87.2669] check_item_in_log+0x1ea/0x2c0 [btrfs] [87.2676] replay_dir_deletes+0x16b/0x380 [btrfs] [87.2684] fixup_inode_link_count+0x34b/0x370 [btrfs] [87.2696] fixup_inode_link_counts+0x41/0x160 [btrfs] [87.2703] btrfs_recover_log_trees+0x1ff/0x7c0 [btrfs] [87.2711] ? __pfx_replay_one_buffer+0x10/0x10 [btrfs] [87.2719] open_ctree+0x10bb/0x15f0 [btrfs] [87.2726] btrfs_get_tree.cold+0xb/0x16c [btrfs] [87.2734] ? fscontext_read+0x15c/0x180 [87.2740] ? rw_verify_area+0x50/0x180 [87.2746] vfs_get_tree+0x25/0xd0 [87.2750] vfs_cmd_create+0x59/0xe0 [87.2755] __do_sys_fsconfig+0x4f6/0x6b0 [87.2760] do_syscall_64+0x50/0x1220 [87.2764] entry_SYSCALL_64_after_hwframe+0x76/0x7e [87.2770] RIP: 0033:0x7f7b9625f4aa [87.2775] Code: 73 01 c3 48 (...) [87.2803] RSP: 002b:00007ffc9ec35b08 EFLAGS: 00000246 ORIG_RAX: 00000000000001af [87.2817] RAX: ffffffffffffffda RBX: 0000558bfa91ac20 RCX: 00007f7b9625f4aa [87.2829] RDX: 0000000000000000 RSI: 0000000000000006 RDI: 0000000000000003 [87.2842] RBP: 0000558bfa91b120 R08: 0000000000000000 R09: 0000000000000000 [87.2854] R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 [87.2864] R13: 00007f7b963f1580 R14: 00007f7b963f326c R15: 00007f7b963d8a23 [87.2877] </TASK> [87.2882] ---[ end trace 0000000000000000 ]--- [87.2891] BTRFS: error (device dm-0 state A) in __btrfs_unlink_inode:4345: errno=-2 No such entry [87.2904] BTRFS: error (device dm-0 state EAO) in do_abort_log_replay:191: errno=-2 No such entry [87.2915] BTRFS critical (device dm-0 state EAO): log tree (for root 5) leaf currently being processed (slot 7 key (258 12 257)): [87.2929] BTRFS info (device dm-0 state EAO): leaf 30736384 gen 10 total ptrs 7 free space 15712 owner 18446744073709551610 [87.2929] BTRFS info (device dm-0 state EAO): refs 3 lock_owner 0 current 638968 [87.2929] item 0 key (257 INODE_ITEM 0) itemoff 16123 itemsize 160 [87.2929] inode generation 9 transid 10 size 0 nbytes 0 [87.2929] block group 0 mode 40755 links 1 uid 0 gid 0 [87.2929] rdev 0 sequence 7 flags 0x0 [87.2929] atime 1765464494.678070921 [87.2929] ctime 1765464494.686606513 [87.2929] mtime 1765464494.686606513 [87.2929] otime 1765464494.678070921 [87.2929] item 1 key (257 INODE_REF 256) itemoff 16109 itemsize 14 [87.2929] index 4 name_len 4 [87.2929] item 2 key (257 DIR_LOG_INDEX 2) itemoff 16101 itemsize 8 [87.2929] dir log end 2 [87.2929] item 3 key (257 DIR_LOG_INDEX 3) itemoff 16093 itemsize 8 [87.2929] dir log end 18446744073709551615 [87.2930] item 4 key (257 DIR_INDEX 3) itemoff 16060 itemsize 33 [87.2930] location key (258 1 0) type 1 [87.2930] transid 10 data_len 0 name_len 3 [87.2930] item 5 key (258 INODE_ITEM 0) itemoff 15900 itemsize 160 [87.2930] inode generation 9 transid 10 size 0 nbytes 0 [87.2930] block group 0 mode 100644 links 1 uid 0 gid 0 [87.2930] rdev 0 sequence 2 flags 0x0 [87.2930] atime 1765464494.678456467 [87.2930] ctime 1765464494.686606513 [87.2930] mtime 1765464494.678456467 [87.2930] otime 1765464494.678456467 [87.2930] item 6 key (258 INODE_REF 257) itemoff 15887 itemsize 13 [87.2930] index 3 name_len 3 [87.2930] BTRFS critical (device dm-0 state EAO): log replay failed in unlink_inode_for_log_replay:1045 for root 5, stage 3, with error -2: failed to unlink inode 256 parent dir 259 name subvol root 5 [87.2963] BTRFS: error (device dm-0 state EAO) in btrfs_recover_log_trees:7743: errno=-2 No such entry [87.2981] BTRFS: error (device dm-0 state EAO) in btrfs_replay_log:2083: errno=-2 No such entry (Failed to recover log tr So fix this by changing copy_inode_items_to_log() to always detect if there are conflicting inodes for the ref/extref of the inode being logged even if the inode was created in a past transaction. A test case for fstests will follow soon. CC: stable@vger.kernel.org # 6.1+ Signed-off-by: Filipe Manana <fdmanana@suse.com> Signed-off-by: David Sterba <dsterba@suse.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2026-01-11btrfs: don't rewrite ret from inode_permissionJosef Bacik1-3/+1
[ Upstream commit 0185c2292c600993199bc6b1f342ad47a9e8c678 ] In our user safe ino resolve ioctl we'll just turn any ret into -EACCES from inode_permission(). This is redundant, and could potentially be wrong if we had an ENOMEM in the security layer or some such other error, so simply return the actual return value. Note: The patch was taken from v5 of fscrypt patchset (https://lore.kernel.org/linux-btrfs/cover.1706116485.git.josef@toxicpanda.com/) which was handled over time by various people: Omar Sandoval, Sweet Tea Dorminy, Josef Bacik. Fixes: 23d0b79dfaed ("btrfs: Add unprivileged version of ino_lookup ioctl") CC: stable@vger.kernel.org # 5.4+ Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com> Signed-off-by: Josef Bacik <josef@toxicpanda.com> Signed-off-by: Daniel Vacek <neelx@suse.com> Reviewed-by: David Sterba <dsterba@suse.com> [ add note ] Signed-off-by: David Sterba <dsterba@suse.com> [ Adjust context ] Signed-off-by: Sasha Levin <sashal@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2026-01-11btrfs: don't log conflicting inode if it's a dir moved in the current ↵Filipe Manana1-0/+38
transaction commit 266273eaf4d99475f1ae57f687b3e42bc71ec6f0 upstream. We can't log a conflicting inode if it's a directory and it was moved from one parent directory to another parent directory in the current transaction, as this can result an attempt to have a directory with two hard links during log replay, one for the old parent directory and another for the new parent directory. The following scenario triggers that issue: 1) We have directories "dir1" and "dir2" created in a past transaction. Directory "dir1" has inode A as its parent directory; 2) We move "dir1" to some other directory; 3) We create a file with the name "dir1" in directory inode A; 4) We fsync the new file. This results in logging the inode of the new file and the inode for the directory "dir1" that was previously moved in the current transaction. So the log tree has the INODE_REF item for the new location of "dir1"; 5) We move the new file to some other directory. This results in updating the log tree to included the new INODE_REF for the new location of the file and removes the INODE_REF for the old location. This happens during the rename when we call btrfs_log_new_name(); 6) We fsync the file, and that persists the log tree changes done in the previous step (btrfs_log_new_name() only updates the log tree in memory); 7) We have a power failure; 8) Next time the fs is mounted, log replay happens and when processing the inode for directory "dir1" we find a new INODE_REF and add that link, but we don't remove the old link of the inode since we have not logged the old parent directory of the directory inode "dir1". As a result after log replay finishes when we trigger writeback of the subvolume tree's extent buffers, the tree check will detect that we have a directory a hard link count of 2 and we get a mount failure. The errors and stack traces reported in dmesg/syslog are like this: [ 3845.729764] BTRFS info (device dm-0): start tree-log replay [ 3845.730304] page: refcount:3 mapcount:0 mapping:000000005c8a3027 index:0x1d00 pfn:0x11510c [ 3845.731236] memcg:ffff9264c02f4e00 [ 3845.731751] aops:btree_aops [btrfs] ino:1 [ 3845.732300] flags: 0x17fffc00000400a(uptodate|private|writeback|node=0|zone=2|lastcpupid=0x1ffff) [ 3845.733346] raw: 017fffc00000400a 0000000000000000 dead000000000122 ffff9264d978aea8 [ 3845.734265] raw: 0000000000001d00 ffff92650e6d4738 00000003ffffffff ffff9264c02f4e00 [ 3845.735305] page dumped because: eb page dump [ 3845.735981] BTRFS critical (device dm-0): corrupt leaf: root=5 block=30408704 slot=6 ino=257, invalid nlink: has 2 expect no more than 1 for dir [ 3845.737786] BTRFS info (device dm-0): leaf 30408704 gen 10 total ptrs 17 free space 14881 owner 5 [ 3845.737789] BTRFS info (device dm-0): refs 4 lock_owner 0 current 30701 [ 3845.737792] item 0 key (256 INODE_ITEM 0) itemoff 16123 itemsize 160 [ 3845.737794] inode generation 3 transid 9 size 16 nbytes 16384 [ 3845.737795] block group 0 mode 40755 links 1 uid 0 gid 0 [ 3845.737797] rdev 0 sequence 2 flags 0x0 [ 3845.737798] atime 1764259517.0 [ 3845.737800] ctime 1764259517.572889464 [ 3845.737801] mtime 1764259517.572889464 [ 3845.737802] otime 1764259517.0 [ 3845.737803] item 1 key (256 INODE_REF 256) itemoff 16111 itemsize 12 [ 3845.737805] index 0 name_len 2 [ 3845.737807] item 2 key (256 DIR_ITEM 2363071922) itemoff 16077 itemsize 34 [ 3845.737808] location key (257 1 0) type 2 [ 3845.737810] transid 9 data_len 0 name_len 4 [ 3845.737811] item 3 key (256 DIR_ITEM 2676584006) itemoff 16043 itemsize 34 [ 3845.737813] location key (258 1 0) type 2 [ 3845.737814] transid 9 data_len 0 name_len 4 [ 3845.737815] item 4 key (256 DIR_INDEX 2) itemoff 16009 itemsize 34 [ 3845.737816] location key (257 1 0) type 2 [ 3845.737818] transid 9 data_len 0 name_len 4 [ 3845.737819] item 5 key (256 DIR_INDEX 3) itemoff 15975 itemsize 34 [ 3845.737820] location key (258 1 0) type 2 [ 3845.737821] transid 9 data_len 0 name_len 4 [ 3845.737822] item 6 key (257 INODE_ITEM 0) itemoff 15815 itemsize 160 [ 3845.737824] inode generation 9 transid 10 size 6 nbytes 0 [ 3845.737825] block group 0 mode 40755 links 2 uid 0 gid 0 [ 3845.737826] rdev 0 sequence 1 flags 0x0 [ 3845.737827] atime 1764259517.572889464 [ 3845.737828] ctime 1764259517.572889464 [ 3845.737830] mtime 1764259517.572889464 [ 3845.737831] otime 1764259517.572889464 [ 3845.737832] item 7 key (257 INODE_REF 256) itemoff 15801 itemsize 14 [ 3845.737833] index 2 name_len 4 [ 3845.737834] item 8 key (257 INODE_REF 258) itemoff 15787 itemsize 14 [ 3845.737836] index 2 name_len 4 [ 3845.737837] item 9 key (257 DIR_ITEM 2507850652) itemoff 15754 itemsize 33 [ 3845.737838] location key (259 1 0) type 1 [ 3845.737839] transid 10 data_len 0 name_len 3 [ 3845.737840] item 10 key (257 DIR_INDEX 2) itemoff 15721 itemsize 33 [ 3845.737842] location key (259 1 0) type 1 [ 3845.737843] transid 10 data_len 0 name_len 3 [ 3845.737844] item 11 key (258 INODE_ITEM 0) itemoff 15561 itemsize 160 [ 3845.737846] inode generation 9 transid 10 size 8 nbytes 0 [ 3845.737847] block group 0 mode 40755 links 1 uid 0 gid 0 [ 3845.737848] rdev 0 sequence 1 flags 0x0 [ 3845.737849] atime 1764259517.572889464 [ 3845.737850] ctime 1764259517.572889464 [ 3845.737851] mtime 1764259517.572889464 [ 3845.737852] otime 1764259517.572889464 [ 3845.737853] item 12 key (258 INODE_REF 256) itemoff 15547 itemsize 14 [ 3845.737855] index 3 name_len 4 [ 3845.737856] item 13 key (258 DIR_ITEM 1843588421) itemoff 15513 itemsize 34 [ 3845.737857] location key (257 1 0) type 2 [ 3845.737858] transid 10 data_len 0 name_len 4 [ 3845.737860] item 14 key (258 DIR_INDEX 2) itemoff 15479 itemsize 34 [ 3845.737861] location key (257 1 0) type 2 [ 3845.737862] transid 10 data_len 0 name_len 4 [ 3845.737863] item 15 key (259 INODE_ITEM 0) itemoff 15319 itemsize 160 [ 3845.737865] inode generation 10 transid 10 size 0 nbytes 0 [ 3845.737866] block group 0 mode 100600 links 1 uid 0 gid 0 [ 3845.737867] rdev 0 sequence 2 flags 0x0 [ 3845.737868] atime 1764259517.580874966 [ 3845.737869] ctime 1764259517.586121869 [ 3845.737870] mtime 1764259517.580874966 [ 3845.737872] otime 1764259517.580874966 [ 3845.737873] item 16 key (259 INODE_REF 257) itemoff 15306 itemsize 13 [ 3845.737874] index 2 name_len 3 [ 3845.737875] BTRFS error (device dm-0): block=30408704 write time tree block corruption detected [ 3845.739448] ------------[ cut here ]------------ [ 3845.740092] WARNING: CPU: 5 PID: 30701 at fs/btrfs/disk-io.c:335 btree_csum_one_bio+0x25a/0x270 [btrfs] [ 3845.741439] Modules linked in: btrfs dm_flakey crc32c_cryptoapi (...) [ 3845.750626] CPU: 5 UID: 0 PID: 30701 Comm: mount Tainted: G W 6.18.0-rc6-btrfs-next-218+ #1 PREEMPT(full) [ 3845.752414] Tainted: [W]=WARN [ 3845.752828] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.16.2-0-gea1b7a073390-prebuilt.qemu.org 04/01/2014 [ 3845.754499] RIP: 0010:btree_csum_one_bio+0x25a/0x270 [btrfs] [ 3845.755460] Code: 31 f6 48 89 (...) [ 3845.758685] RSP: 0018:ffffa8d9c5677678 EFLAGS: 00010246 [ 3845.759450] RAX: 0000000000000000 RBX: ffff92650e6d4738 RCX: 0000000000000000 [ 3845.760309] RDX: 0000000000000000 RSI: ffffffff9aab45b9 RDI: ffff9264c4748000 [ 3845.761239] RBP: ffff9264d4324000 R08: 0000000000000000 R09: ffffa8d9c5677468 [ 3845.762607] R10: ffff926bdc1fffa8 R11: 0000000000000003 R12: ffffa8d9c5677680 [ 3845.764099] R13: 0000000000004000 R14: ffff9264dd624000 R15: ffff9264d978aba8 [ 3845.765094] FS: 00007f751fa5a840(0000) GS:ffff926c42a82000(0000) knlGS:0000000000000000 [ 3845.766226] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 3845.766970] CR2: 0000558df1815380 CR3: 000000010ed88003 CR4: 0000000000370ef0 [ 3845.768009] Call Trace: [ 3845.768392] <TASK> [ 3845.768714] btrfs_submit_bbio+0x6ee/0x7f0 [btrfs] [ 3845.769640] ? write_one_eb+0x28e/0x340 [btrfs] [ 3845.770588] btree_write_cache_pages+0x2f0/0x550 [btrfs] [ 3845.771286] ? alloc_extent_state+0x19/0x100 [btrfs] [ 3845.771967] ? merge_next_state+0x1a/0x90 [btrfs] [ 3845.772586] ? set_extent_bit+0x233/0x8b0 [btrfs] [ 3845.773198] ? xas_load+0x9/0xc0 [ 3845.773589] ? xas_find+0x14d/0x1a0 [ 3845.773969] do_writepages+0xc6/0x160 [ 3845.774367] filemap_fdatawrite_wbc+0x48/0x60 [ 3845.775003] __filemap_fdatawrite_range+0x5b/0x80 [ 3845.775902] btrfs_write_marked_extents+0x61/0x170 [btrfs] [ 3845.776707] btrfs_write_and_wait_transaction+0x4e/0xc0 [btrfs] [ 3845.777379] ? _raw_spin_unlock_irqrestore+0x23/0x40 [ 3845.777923] btrfs_commit_transaction+0x5ea/0xd20 [btrfs] [ 3845.778551] ? _raw_spin_unlock+0x15/0x30 [ 3845.778986] ? release_extent_buffer+0x34/0x160 [btrfs] [ 3845.779659] btrfs_recover_log_trees+0x7a3/0x7c0 [btrfs] [ 3845.780416] ? __pfx_replay_one_buffer+0x10/0x10 [btrfs] [ 3845.781499] open_ctree+0x10bb/0x15f0 [btrfs] [ 3845.782194] btrfs_get_tree.cold+0xb/0x16c [btrfs] [ 3845.782764] ? fscontext_read+0x15c/0x180 [ 3845.783202] ? rw_verify_area+0x50/0x180 [ 3845.783667] vfs_get_tree+0x25/0xd0 [ 3845.784047] vfs_cmd_create+0x59/0xe0 [ 3845.784458] __do_sys_fsconfig+0x4f6/0x6b0 [ 3845.784914] do_syscall_64+0x50/0x1220 [ 3845.785340] entry_SYSCALL_64_after_hwframe+0x76/0x7e [ 3845.785980] RIP: 0033:0x7f751fc7f4aa [ 3845.786759] Code: 73 01 c3 48 (...) [ 3845.789951] RSP: 002b:00007ffcdba45dc8 EFLAGS: 00000246 ORIG_RAX: 00000000000001af [ 3845.791402] RAX: ffffffffffffffda RBX: 000055ccc8291c20 RCX: 00007f751fc7f4aa [ 3845.792688] RDX: 0000000000000000 RSI: 0000000000000006 RDI: 0000000000000003 [ 3845.794308] RBP: 000055ccc8292120 R08: 0000000000000000 R09: 0000000000000000 [ 3845.795829] R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 [ 3845.797183] R13: 00007f751fe11580 R14: 00007f751fe1326c R15: 00007f751fdf8a23 [ 3845.798633] </TASK> [ 3845.799067] ---[ end trace 0000000000000000 ]--- [ 3845.800215] BTRFS: error (device dm-0) in btrfs_commit_transaction:2553: errno=-5 IO failure (Error while writing out transaction) [ 3845.801860] BTRFS warning (device dm-0 state E): Skipping commit of aborted transaction. [ 3845.802815] BTRFS error (device dm-0 state EA): Transaction aborted (error -5) [ 3845.803728] BTRFS: error (device dm-0 state EA) in cleanup_transaction:2036: errno=-5 IO failure [ 3845.805374] BTRFS: error (device dm-0 state EA) in btrfs_replay_log:2083: errno=-5 IO failure (Failed to recover log tree) [ 3845.807919] BTRFS error (device dm-0 state EA): open_ctree failed: -5 Fix this by never logging a conflicting inode that is a directory and was moved in the current transaction (its last_unlink_trans equals the current transaction) and instead fallback to a transaction commit. A test case for fstests will follow soon. Reported-by: Vyacheslav Kovalevsky <slva.kovalevskiy.2014@gmail.com> Link: https://lore.kernel.org/linux-btrfs/7bbc9419-5c56-450a-b5a0-efeae7457113@gmail.com/ CC: stable@vger.kernel.org # 6.1+ Signed-off-by: Filipe Manana <fdmanana@suse.com> Signed-off-by: David Sterba <dsterba@suse.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2026-01-11btrfs: scrub: always update btrfs_scrub_progress::last_physicalQu Wenruo1-0/+5
[ Upstream commit 54df8b80cc63aa0f22c4590cad11542731ed43ff ] [BUG] When a scrub failed immediately without any byte scrubbed, the returned btrfs_scrub_progress::last_physical will always be 0, even if there is a non-zero @start passed into btrfs_scrub_dev() for resume cases. This will reset the progress and make later scrub resume start from the beginning. [CAUSE] The function btrfs_scrub_dev() accepts a @progress parameter to copy its updated progress to the caller, there are cases where we either don't touch progress::last_physical at all or copy 0 into last_physical: - last_physical not updated at all If some error happened before scrubbing any super block or chunk, we will not copy the progress, leaving the @last_physical untouched. E.g. failed to allocate @sctx, scrubbing a missing device or even there is already a running scrub and so on. All those cases won't touch @progress at all, resulting the last_physical untouched and will be left as 0 for most cases. - Error out before scrubbing any bytes In those case we allocated @sctx, and sctx->stat.last_physical is all zero (initialized by kvzalloc()). Unfortunately some critical errors happened during scrub_enumerate_chunks() or scrub_supers() before any stripe is really scrubbed. In that case although we will copy sctx->stat back to @progress, since no byte is really scrubbed, last_physical will be overwritten to 0. [FIX] Make sure the parameter @progress always has its @last_physical member updated to @start parameter inside btrfs_scrub_dev(). At the very beginning of the function, set @progress->last_physical to @start, so that even if we error out without doing progress copying, last_physical is still at @start. Then after we got @sctx allocated, set sctx->stat.last_physical to @start, this will make sure even if we didn't get any byte scrubbed, at the progress copying stage the @last_physical is not left as zero. This should resolve the resume progress reset problem. Signed-off-by: Qu Wenruo <wqu@suse.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
2026-01-11btrfs: fix memory leak of fs_devices in degraded seed device pathDeepanshu Kartikey1-0/+1
[ Upstream commit b57f2ddd28737db6ff0e9da8467f0ab9d707e997 ] In open_seed_devices(), when find_fsid() fails and we're in DEGRADED mode, a new fs_devices is allocated via alloc_fs_devices() but is never added to the seed_list before returning. This contrasts with the normal path where fs_devices is properly added via list_add(). If any error occurs later in read_one_dev() or btrfs_read_chunk_tree(), the cleanup code iterates seed_list to free seed devices, but this orphaned fs_devices is never found and never freed, causing a memory leak. Any devices allocated via add_missing_dev() and attached to this fs_devices are also leaked. Fix this by adding the newly allocated fs_devices to seed_list in the degraded path, consistent with the normal path. Fixes: 5f37583569442 ("Btrfs: move the missing device to its own fs device list") Reported-by: syzbot+eadd98df8bceb15d7fed@syzkaller.appspotmail.com Closes: https://syzkaller.appspot.com/bug?extid=eadd98df8bceb15d7fed Tested-by: syzbot+eadd98df8bceb15d7fed@syzkaller.appspotmail.com Reviewed-by: Qu Wenruo <wqu@suse.com> Signed-off-by: Deepanshu Kartikey <kartikey406@gmail.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
2026-01-11btrfs: fix a potential path leak in print_data_reloc_error()Qu Wenruo1-0/+1
[ Upstream commit 313ef70a9f0f637a09d9ef45222f5bdcf30a354b ] Inside print_data_reloc_error(), if extent_from_logical() failed we return immediately. However there are the following cases where extent_from_logical() can return error but still holds a path: - btrfs_search_slot() returned 0 - No backref item found in extent tree - No flags_ret provided This is not possible in this call site though. So for the above two cases, we can return without releasing the path, causing extent buffer leaks. Fixes: b9a9a85059cd ("btrfs: output affected files when relocation fails") Signed-off-by: Qu Wenruo <wqu@suse.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
2026-01-11btrfs: do not skip logging new dentries when logging a new nameFilipe Manana1-8/+0
[ Upstream commit 5630f7557de61264ccb4f031d4734a1a97eaed16 ] When we are logging a directory and the log context indicates that we are logging a new name for some other file (that is or was inside that directory), we skip logging the inodes for new dentries in the directory. This is ok most of the time, but if after the rename or link operation that triggered the logging of that directory, we have an explicit fsync of that directory without the directory inode being evicted and reloaded, we end up never logging the inodes for the new dentries that we found during the new name logging, as the next directory fsync will only process dentries that were added after the last time we logged the directory (we are doing an incremental directory logging). So make sure we always log new dentries for a directory even if we are in a context of logging a new name. We started skipping logging inodes for new dentries as of commit c48792c6ee7a ("btrfs: do not log new dentries when logging that a new name exists") and it was fine back then, because when logging a directory we always iterated over all the directory entries (for leaves changed in the current transaction) so a subsequent fsync would always log anything that was previously skipped while logging a directory when logging a new name (with btrfs_log_new_name()). But later support for incrementally logging a directory was added in commit dc2872247ec0 ("btrfs: keep track of the last logged keys when logging a directory"), to avoid checking all dir items every time we log a directory, so the check to skip dentry logging added in the first commit should have been removed when the incremental support for logging a directory was added. A test case for fstests will follow soon. Reported-by: Vyacheslav Kovalevsky <slava.kovalevskiy.2014@gmail.com> Link: https://lore.kernel.org/linux-btrfs/84c4e713-85d6-42b9-8dcf-0722ed26cb05@gmail.com/ Fixes: dc2872247ec0 ("btrfs: keep track of the last logged keys when logging a directory") Reviewed-by: Boris Burkov <boris@bur.io> Signed-off-by: Filipe Manana <fdmanana@suse.com> Signed-off-by: David Sterba <dsterba@suse.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
2026-01-11btrfs: fix leaf leak in an error path in btrfs_del_items()Filipe Manana1-1/+1
[ Upstream commit e7dd1182fcedee7c6097c9f49eba8de94a4364e3 ] If the call to btrfs_del_leaf() fails we return without decrementing the extra ref we took on the leaf, therefore leaking it. Fix this by ensuring we drop the ref count before returning the error. Fixes: 751a27615dda ("btrfs: do not BUG_ON() on tree mod log failures at btrfs_del_ptr()") Reviewed-by: Qu Wenruo <wqu@suse.com> Signed-off-by: Filipe Manana <fdmanana@suse.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
2025-11-24btrfs: ensure no dirty metadata is written back for an fs with errorsQu Wenruo1-0/+8
[ Upstream commit 2618849f31e7cf51fadd4a5242458501a6d5b315 ] [BUG] During development of a minor feature (make sure all btrfs_bio::end_io() is called in task context), I noticed a crash in generic/388, where metadata writes triggered new works after btrfs_stop_all_workers(). It turns out that it can even happen without any code modification, just using RAID5 for metadata and the same workload from generic/388 is going to trigger the use-after-free. [CAUSE] If btrfs hits an error, the fs is marked as error, no new transaction is allowed thus metadata is in a frozen state. But there are some metadata modifications before that error, and they are still in the btree inode page cache. Since there will be no real transaction commit, all those dirty folios are just kept as is in the page cache, and they can not be invalidated by invalidate_inode_pages2() call inside close_ctree(), because they are dirty. And finally after btrfs_stop_all_workers(), we call iput() on btree inode, which triggers writeback of those dirty metadata. And if the fs is using RAID56 metadata, this will trigger RMW and queue new works into rmw_workers, which is already stopped, causing warning from queue_work() and use-after-free. [FIX] Add a special handling for write_one_eb(), that if the fs is already in an error state, immediately mark the bbio as failure, instead of really submitting them. Then during close_ctree(), iput() will just discard all those dirty tree blocks without really writing them back, thus no more new jobs for already stopped-and-freed workqueues. The extra discard in write_one_eb() also acts as an extra safenet. E.g. the transaction abort is triggered by some extent/free space tree corruptions, and since extent/free space tree is already corrupted some tree blocks may be allocated where they shouldn't be (overwriting existing tree blocks). In that case writing them back will further corrupting the fs. CC: stable@vger.kernel.org # 6.6+ Reviewed-by: Filipe Manana <fdmanana@suse.com> Signed-off-by: Qu Wenruo <wqu@suse.com> Signed-off-by: David Sterba <dsterba@suse.com> [ Adjust context ] Signed-off-by: Sasha Levin <sashal@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2025-11-24btrfs: do not update last_log_commit when logging inode due to a new nameFilipe Manana1-1/+1
commit bfe3d755ef7cec71aac6ecda34a107624735aac7 upstream. When logging that a new name exists, we skip updating the inode's last_log_commit field to prevent a later explicit fsync against the inode from doing nothing (as updating last_log_commit makes btrfs_inode_in_log() return true). We are detecting, at btrfs_log_inode(), that logging a new name is happening by checking the logging mode is not LOG_INODE_EXISTS, but that is not enough because we may log parent directories when logging a new name of a file in LOG_INODE_ALL mode - we need to check that the logging_new_name field of the log context too. An example scenario where this results in an explicit fsync against a directory not persisting changes to the directory is the following: $ mkfs.btrfs -f /dev/sdc $ mount /dev/sdc /mnt $ touch /mnt/foo $ sync $ mkdir /mnt/dir # Write some data to our file and fsync it. $ xfs_io -c "pwrite -S 0xab 0 64K" -c "fsync" /mnt/foo # Add a new link to our file. Since the file was logged before, we # update it in the log tree by calling btrfs_log_new_name(). $ ln /mnt/foo /mnt/dir/bar # fsync the root directory - we expect it to persist the dentry for # the new directory "dir". $ xfs_io -c "fsync" /mnt <power fail> After mounting the fs the entry for directory "dir" does not exists, despite the explicit fsync on the root directory. Here's why this happens: 1) When we fsync the file we log the inode, so that it's present in the log tree; 2) When adding the new link we enter btrfs_log_new_name(), and since the inode is in the log tree we proceed to updating the inode in the log tree; 3) We first set the inode's last_unlink_trans to the current transaction (early in btrfs_log_new_name()); 4) We then eventually enter btrfs_log_inode_parent(), and after logging the file's inode, we call btrfs_log_all_parents() because the inode's last_unlink_trans matches the current transaction's ID (updated in the previous step); 5) So btrfs_log_all_parents() logs the root directory by calling btrfs_log_inode() for the root's inode with a log mode of LOG_INODE_ALL so that new dentries are logged; 6) At btrfs_log_inode(), because the log mode is LOG_INODE_ALL, we update root inode's last_log_commit to the last transaction that changed the inode (->last_sub_trans field of the inode), which corresponds to the current transaction's ID; 7) Then later when user space explicitly calls fsync against the root directory, we enter btrfs_sync_file(), which calls skip_inode_logging() and that returns true, since its call to btrfs_inode_in_log() returns true and there are no ordered extents (it's a directory, never has ordered extents). This results in btrfs_sync_file() returning without syncing the log or committing the current transaction, so all the updates we did when logging the new name, including logging the root directory, are not persisted. So fix this by but updating the inode's last_log_commit if we are sure we are not logging a new name (if ctx->logging_new_name is false). A test case for fstests will follow soon. Reported-by: Vyacheslav Kovalevsky <slava.kovalevskiy.2014@gmail.com> Link: https://lore.kernel.org/linux-btrfs/03c5d7ec-5b3d-49d1-95bc-8970a7f82d87@gmail.com/ Fixes: 130341be7ffa ("btrfs: always update the logged transaction when logging new names") CC: stable@vger.kernel.org # 6.1+ Signed-off-by: Filipe Manana <fdmanana@suse.com> Signed-off-by: David Sterba <dsterba@suse.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2025-11-24btrfs: scrub: put bio after errors in scrub_raid56_parity_stripe()Zilin Guan1-0/+2
commit 5fea61aa1ca70c4b3738eebad9ce2d7e7938ebbd upstream. scrub_raid56_parity_stripe() allocates a bio with bio_alloc(), but fails to release it on some error paths, leading to a potential memory leak. Add the missing bio_put() calls to properly drop the bio reference in those error cases. Fixes: 1009254bf22a3 ("btrfs: scrub: use scrub_stripe to implement RAID56 P/Q scrub") CC: stable@vger.kernel.org # 6.6+ Reviewed-by: Qu Wenruo <wqu@suse.com> Signed-off-by: Zilin Guan <zilin@seu.edu.cn> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2025-11-24btrfs: mark dirty extent range for out of bound prealloc extentsaustinchang1-0/+10
[ Upstream commit 3b1a4a59a2086badab391687a6a0b86e03048393 ] In btrfs_fallocate(), when the allocated range overlaps with a prealloc extent and the extent starts after i_size, the range doesn't get marked dirty in file_extent_tree. This results in persisting an incorrect disk_i_size for the inode when not using the no-holes feature. This is reproducible since commit 41a2ee75aab0 ("btrfs: introduce per-inode file extent tree"), then became hidden since commit 3d7db6e8bd22 ("btrfs: don't allocate file extent tree for non regular files") and then visible again after commit 8679d2687c35 ("btrfs: initialize inode::file_extent_tree after i_mode has been set"), which fixes the previous commit. The following reproducer triggers the problem: $ cat test.sh MNT=/mnt/test DEV=/dev/vdb mkdir -p $MNT mkfs.btrfs -f -O ^no-holes $DEV mount $DEV $MNT touch $MNT/file1 fallocate -n -o 1M -l 2M $MNT/file1 umount $MNT mount $DEV $MNT len=$((1 * 1024 * 1024)) fallocate -o 1M -l $len $MNT/file1 du --bytes $MNT/file1 umount $MNT mount $DEV $MNT du --bytes $MNT/file1 umount $MNT Running the reproducer gives the following result: $ ./test.sh (...) 2097152 /mnt/test/file1 1048576 /mnt/test/file1 The difference is exactly 1048576 as we assigned. Fix by adding a call to btrfs_inode_set_file_extent_range() in btrfs_fallocate_update_isize(). Fixes: 41a2ee75aab0 ("btrfs: introduce per-inode file extent tree") Signed-off-by: austinchang <austinchang@synology.com> Reviewed-by: Filipe Manana <fdmanana@suse.com> Signed-off-by: Filipe Manana <fdmanana@suse.com> Signed-off-by: David Sterba <dsterba@suse.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
2025-11-02btrfs: use smp_mb__after_atomic() when forcing COW in create_pending_snapshot()Filipe Manana1-1/+1
[ Upstream commit 45c222468d33202c07c41c113301a4b9c8451b8f ] After setting the BTRFS_ROOT_FORCE_COW flag on the root we are doing a full write barrier, smp_wmb(), but we don't need to, all we need is a smp_mb__after_atomic(). The use of the smp_wmb() is from the old days when we didn't use a bit and used instead an int field in the root to signal if cow is forced. After the int field was changed to a bit in the root's state (flags field), we forgot to update the memory barrier in create_pending_snapshot() to smp_mb__after_atomic(), but we did the change in commit_fs_roots() after clearing BTRFS_ROOT_FORCE_COW. That happened in commit 27cdeb7096b8 ("Btrfs: use bitfield instead of integer data type for the some variants in btrfs_root"). On the reader side, in should_cow_block(), we also use the counterpart smp_mb__before_atomic() which generates further confusion. So change the smp_wmb() to smp_mb__after_atomic(). In fact we don't even need any barrier at all since create_pending_snapshot() is called in the critical section of a transaction commit and therefore no one can concurrently join/attach the transaction, or start a new one, until the transaction is unblocked. By the time someone starts a new transaction and enters should_cow_block(), a lot of implicit memory barriers already took place by having acquired several locks such as fs_info->trans_lock and extent buffer locks on the root node at least. Nevertlheless, for consistency use smp_mb__after_atomic() after setting the force cow bit in create_pending_snapshot(). Signed-off-by: Filipe Manana <fdmanana@suse.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
2025-11-02btrfs: use level argument in log tree walk callback replay_one_buffer()Filipe Manana1-5/+3
[ Upstream commit 6cb7f0b8c9b0d6a35682335fea88bd26f089306f ] We already have the extent buffer's level in an argument, there's no need to first ensure the extent buffer's data is loaded (by calling btrfs_read_extent_buffer()) and then call btrfs_header_level() to check the level. So use the level argument and do the check before calling btrfs_read_extent_buffer(). Signed-off-by: Filipe Manana <fdmanana@suse.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
2025-11-02btrfs: always drop log root tree reference in btrfs_replay_log()Filipe Manana2-2/+1
[ Upstream commit 2f5b8095ea47b142c56c09755a8b1e14145a2d30 ] Currently we have this odd behaviour: 1) At btrfs_replay_log() we drop the reference of the log root tree if the call to btrfs_recover_log_trees() failed; 2) But if the call to btrfs_recover_log_trees() did not fail, we don't drop the reference in btrfs_replay_log() - we expect that btrfs_recover_log_trees() does it in case it returns success. Let's simplify this and make btrfs_replay_log() always drop the reference on the log root tree, not only this simplifies code as it's what makes sense since it's btrfs_replay_log() who grabbed the reference in the first place. Signed-off-by: Filipe Manana <fdmanana@suse.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
2025-11-02btrfs: scrub: replace max_t()/min_t() with clamp() in scrub_throttle_dev_io()Thorsten Blum1-2/+1
[ Upstream commit a7f3dfb8293c4cee99743132d69863a92e8f4875 ] Replace max_t() followed by min_t() with a single clamp(). As was pointed by David Laight in https://lore.kernel.org/linux-btrfs/20250906122458.75dfc8f0@pumpkin/ the calculation may overflow u32 when the input value is too large, so clamp_t() is not used. In practice the expected values are in range of megabytes to gigabytes (throughput limit) so the bug would not happen. Signed-off-by: Thorsten Blum <thorsten.blum@linux.dev> Reviewed-by: David Sterba <dsterba@suse.com> [ Use clamp() and add explanation. ] Signed-off-by: David Sterba <dsterba@suse.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
2025-11-02btrfs: zoned: refine extent allocator hint selectionNaohiro Aota1-2/+4
[ Upstream commit 0d703963d297964451783e1a0688ebdf74cd6151 ] The hint block group selection in the extent allocator is wrong in the first place, as it can select the dedicated data relocation block group for the normal data allocation. Since we separated the normal data space_info and the data relocation space_info, we can easily identify a block group is for data relocation or not. Do not choose it for the normal data allocation. Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com> Signed-off-by: Naohiro Aota <naohiro.aota@wdc.com> Signed-off-by: David Sterba <dsterba@suse.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
2025-11-02btrfs: zoned: return error from btrfs_zone_finish_endio()Johannes Thumshirn3-9/+15
[ Upstream commit 3c44cd3c79fcb38a86836dea6ff8fec322a9e68c ] Now that btrfs_zone_finish_endio_workfn() is directly calling do_zone_finish() the only caller of btrfs_zone_finish_endio() is btrfs_finish_one_ordered(). btrfs_finish_one_ordered() already has error handling in-place so btrfs_zone_finish_endio() can return an error if the block group lookup fails. Also as btrfs_zone_finish_endio() already checks for zoned filesystems and returns early, there's no need to do this in the caller. Reviewed-by: Damien Le Moal <dlemoal@kernel.org> Signed-off-by: Johannes Thumshirn <johannes.thumshirn@wdc.com> Signed-off-by: David Sterba <dsterba@suse.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
2025-10-23btrfs: do not assert we found block group item when creating free space treeFilipe Manana1-7/+8
commit a5a51bf4e9b7354ce7cd697e610d72c1b33fd949 upstream. Currently, when building a free space tree at populate_free_space_tree(), if we are not using the block group tree feature, we always expect to find block group items (either extent items or a block group item with key type BTRFS_BLOCK_GROUP_ITEM_KEY) when we search the extent tree with btrfs_search_slot_for_read(), so we assert that we found an item. However this expectation is wrong since we can have a new block group created in the current transaction which is still empty and for which we still have not added the block group's item to the extent tree, in which case we do not have any items in the extent tree associated to the block group. The insertion of a new block group's block group item in the extent tree happens at btrfs_create_pending_block_groups() when it calls the helper insert_block_group_item(). This typically is done when a transaction handle is released, committed or when running delayed refs (either as part of a transaction commit or when serving tickets for space reservation if we are low on free space). So remove the assertion at populate_free_space_tree() even when the block group tree feature is not enabled and update the comment to mention this case. Syzbot reported this with the following stack trace: BTRFS info (device loop3 state M): rebuilding free space tree assertion failed: ret == 0 :: 0, in fs/btrfs/free-space-tree.c:1115 ------------[ cut here ]------------ kernel BUG at fs/btrfs/free-space-tree.c:1115! Oops: invalid opcode: 0000 [#1] SMP KASAN PTI CPU: 1 UID: 0 PID: 6352 Comm: syz.3.25 Not tainted syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/18/2025 RIP: 0010:populate_free_space_tree+0x700/0x710 fs/btrfs/free-space-tree.c:1115 Code: ff ff e8 d3 (...) RSP: 0018:ffffc9000430f780 EFLAGS: 00010246 RAX: 0000000000000043 RBX: ffff88805b709630 RCX: fea61d0e2e79d000 RDX: 0000000000000000 RSI: 0000000080000000 RDI: 0000000000000000 RBP: ffffc9000430f8b0 R08: ffffc9000430f4a7 R09: 1ffff92000861e94 R10: dffffc0000000000 R11: fffff52000861e95 R12: 0000000000000001 R13: 1ffff92000861f00 R14: dffffc0000000000 R15: 0000000000000000 FS: 00007f424d9fe6c0(0000) GS:ffff888125afc000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fd78ad212c0 CR3: 0000000076d68000 CR4: 00000000003526f0 Call Trace: <TASK> btrfs_rebuild_free_space_tree+0x1ba/0x6d0 fs/btrfs/free-space-tree.c:1364 btrfs_start_pre_rw_mount+0x128f/0x1bf0 fs/btrfs/disk-io.c:3062 btrfs_remount_rw fs/btrfs/super.c:1334 [inline] btrfs_reconfigure+0xaed/0x2160 fs/btrfs/super.c:1559 reconfigure_super+0x227/0x890 fs/super.c:1076 do_remount fs/namespace.c:3279 [inline] path_mount+0xd1a/0xfe0 fs/namespace.c:4027 do_mount fs/namespace.c:4048 [inline] __do_sys_mount fs/namespace.c:4236 [inline] __se_sys_mount+0x313/0x410 fs/namespace.c:4213 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xfa/0xfa0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f424e39066a Code: d8 64 89 02 (...) RSP: 002b:00007f424d9fde68 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5 RAX: ffffffffffffffda RBX: 00007f424d9fdef0 RCX: 00007f424e39066a RDX: 0000200000000180 RSI: 0000200000000380 RDI: 0000000000000000 RBP: 0000200000000180 R08: 00007f424d9fdef0 R09: 0000000000000020 R10: 0000000000000020 R11: 0000000000000246 R12: 0000200000000380 R13: 00007f424d9fdeb0 R14: 0000000000000000 R15: 00002000000002c0 </TASK> Modules linked in: ---[ end trace 0000000000000000 ]--- Reported-by: syzbot+884dc4621377ba579a6f@syzkaller.appspotmail.com Link: https://lore.kernel.org/linux-btrfs/68dc3dab.a00a0220.102ee.004e.GAE@google.com/ Fixes: a5ed91828518 ("Btrfs: implement the free space B-tree") CC: <stable@vger.kernel.org> # 6.1.x: 1961d20f6fa8: btrfs: fix assertion when building free space tree CC: <stable@vger.kernel.org> # 6.1.x Reviewed-by: Qu Wenruo <wqu@suse.com> Signed-off-by: Filipe Manana <fdmanana@suse.com> Signed-off-by: David Sterba <dsterba@suse.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2025-10-23btrfs: fix incorrect readahead expansion lengthBoris Burkov1-1/+1
commit 8ab2fa69691b2913a67f3c54fbb991247b3755be upstream. The intent of btrfs_readahead_expand() was to expand to the length of the current compressed extent being read. However, "ram_bytes" is *not* that, in the case where a single physical compressed extent is used for multiple file extents. Consider this case with a large compressed extent C and then later two non-compressed extents N1 and N2 written over C, leaving C1 and C2 pointing to offset/len pairs of C: [ C ] [ N1 ][ C1 ][ N2 ][ C2 ] In such a case, ram_bytes for both C1 and C2 is the full uncompressed length of C. So starting readahead in C1 will expand the readahead past the end of C1, past N2, and into C2. This will then expand readahead again, to C2_start + ram_bytes, way past EOF. First of all, this is totally undesirable, we don't want to read the whole file in arbitrary chunks of the large underlying extent if it happens to exist. Secondly, it results in zeroing the range past the end of C2 up to ram_bytes. This is particularly unpleasant with fs-verity as it can zero and set uptodate pages in the verity virtual space past EOF. This incorrect readahead behavior can lead to verity verification errors, if we iterate in a way that happens to do the wrong readahead. Fix this by using em->len for readahead expansion, not em->ram_bytes, resulting in the expected behavior of stopping readahead at the extent boundary. Reported-by: Max Chernoff <git@maxchernoff.ca> Link: https://bugzilla.redhat.com/show_bug.cgi?id=2399898 Fixes: 9e9ff875e417 ("btrfs: use readahead_expand() on compressed extents") CC: stable@vger.kernel.org # 6.17 Reviewed-by: Filipe Manana <fdmanana@suse.com> Signed-off-by: Boris Burkov <boris@bur.io> Signed-off-by: David Sterba <dsterba@suse.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2025-10-23btrfs: fix clearing of BTRFS_FS_RELOC_RUNNING if relocation already runningFilipe Manana1-6/+7
commit 7e5a5983edda664e8e4bb20af17b80f5135c655c upstream. When starting relocation, at reloc_chunk_start(), if we happen to find the flag BTRFS_FS_RELOC_RUNNING is already set we return an error (-EINPROGRESS) to the callers, however the callers call reloc_chunk_end() which will clear the flag BTRFS_FS_RELOC_RUNNING, which is wrong since relocation was started by another task and still running. Finding the BTRFS_FS_RELOC_RUNNING flag already set is an unexpected scenario, but still our current behaviour is not correct. Fix this by never calling reloc_chunk_end() if reloc_chunk_start() has returned an error, which is what logically makes sense, since the general widespread pattern is to have end functions called only if the counterpart start functions succeeded. This requires changing reloc_chunk_start() to clear BTRFS_FS_RELOC_RUNNING if there's a pending cancel request. Fixes: 907d2710d727 ("btrfs: add cancellable chunk relocation support") CC: stable@vger.kernel.org # 5.15+ Reviewed-by: Boris Burkov <boris@bur.io> Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com> Reviewed-by: Qu Wenruo <wqu@suse.com> Signed-off-by: Filipe Manana <fdmanana@suse.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2025-10-19btrfs: fix the incorrect max_bytes value for find_lock_delalloc_range()Qu Wenruo1-3/+11
[ Upstream commit 7b26da407420e5054e3f06c5d13271697add9423 ] [BUG] With my local branch to enable bs > ps support for btrfs, sometimes I hit the following ASSERT() inside submit_one_sector(): ASSERT(block_start != EXTENT_MAP_HOLE); Please note that it's not yet possible to hit this ASSERT() in the wild yet, as it requires btrfs bs > ps support, which is not even in the development branch. But on the other hand, there is also a very low chance to hit above ASSERT() with bs < ps cases, so this is an existing bug affect not only the incoming bs > ps support but also the existing bs < ps support. [CAUSE] Firstly that ASSERT() means we're trying to submit a dirty block but without a real extent map nor ordered extent map backing it. Furthermore with extra debugging, the folio triggering such ASSERT() is always larger than the fs block size in my bs > ps case. (8K block size, 4K page size) After some more debugging, the ASSERT() is trigger by the following sequence: extent_writepage() | We got a 32K folio (4 fs blocks) at file offset 0, and the fs block | size is 8K, page size is 4K. | And there is another 8K folio at file offset 32K, which is also | dirty. | So the filemap layout looks like the following: | | "||" is the filio boundary in the filemap. | "//| is the dirty range. | | 0 8K 16K 24K 32K 40K | |////////| |//////////////////////||////////| | |- writepage_delalloc() | |- find_lock_delalloc_range() for [0, 8K) | | Now range [0, 8K) is properly locked. | | | |- find_lock_delalloc_range() for [16K, 40K) | | |- btrfs_find_delalloc_range() returned range [16K, 40K) | | |- lock_delalloc_folios() locked folio 0 successfully | | | | | | The filemap range [32K, 40K) got dropped from filemap. | | | | | |- lock_delalloc_folios() failed with -EAGAIN on folio 32K | | | As the folio at 32K is dropped. | | | | | |- loops = 1; | | |- max_bytes = PAGE_SIZE; | | |- goto again; | | | This will re-do the lookup for dirty delalloc ranges. | | | | | |- btrfs_find_delalloc_range() called with @max_bytes == 4K | | | This is smaller than block size, so | | | btrfs_find_delalloc_range() is unable to return any range. | | \- return false; | | | \- Now only range [0, 8K) has an OE for it, but for dirty range | [16K, 32K) it's dirty without an OE. | This breaks the assumption that writepage_delalloc() will find | and lock all dirty ranges inside the folio. | |- extent_writepage_io() |- submit_one_sector() for [0, 8K) | Succeeded | |- submit_one_sector() for [16K, 24K) Triggering the ASSERT(), as there is no OE, and the original extent map is a hole. Please note that, this also exposed the same problem for bs < ps support. E.g. with 64K page size and 4K block size. If we failed to lock a folio, and falls back into the "loops = 1;" branch, we will re-do the search using 64K as max_bytes. Which may fail again to lock the next folio, and exit early without handling all dirty blocks inside the folio. [FIX] Instead of using the fixed size PAGE_SIZE as @max_bytes, use @sectorsize, so that we are ensured to find and lock any remaining blocks inside the folio. And since we're here, add an extra ASSERT() to before calling btrfs_find_delalloc_range() to make sure the @max_bytes is at least no smaller than a block to avoid false negative. Cc: stable@vger.kernel.org # 5.15+ Signed-off-by: Qu Wenruo <wqu@suse.com> Signed-off-by: David Sterba <dsterba@suse.com> [ adapted folio terminology and API calls to page-based equivalents ] Signed-off-by: Sasha Levin <sashal@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2025-10-19btrfs: avoid potential out-of-bounds in btrfs_encode_fh()Anderson Nascimento1-1/+7
commit dff4f9ff5d7f289e4545cc936362e01ed3252742 upstream. The function btrfs_encode_fh() does not properly account for the three cases it handles. Before writing to the file handle (fh), the function only returns to the user BTRFS_FID_SIZE_NON_CONNECTABLE (5 dwords, 20 bytes) or BTRFS_FID_SIZE_CONNECTABLE (8 dwords, 32 bytes). However, when a parent exists and the root ID of the parent and the inode are different, the function writes BTRFS_FID_SIZE_CONNECTABLE_ROOT (10 dwords, 40 bytes). If *max_len is not large enough, this write goes out of bounds because BTRFS_FID_SIZE_CONNECTABLE_ROOT is greater than BTRFS_FID_SIZE_CONNECTABLE originally returned. This results in an 8-byte out-of-bounds write at fid->parent_root_objectid = parent_root_id. A previous attempt to fix this issue was made but was lost. https://lore.kernel.org/all/4CADAEEC020000780001B32C@vpn.id2.novell.com/ Although this issue does not seem to be easily triggerable, it is a potential memory corruption bug that should be fixed. This patch resolves the issue by ensuring the function returns the appropriate size for all three cases and validates that *max_len is large enough before writing any data. Fixes: be6e8dc0ba84 ("NFS support for btrfs - v3") CC: stable@vger.kernel.org # 3.0+ Signed-off-by: Anderson Nascimento <anderson@allelesecurity.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2025-10-12btrfs: ref-verify: handle damaged extent root treeDavid Sterba1-1/+8
[ Upstream commit ed4e6b5d644c4dd2bc2872ffec036b7da0ec2e27 ] Syzbot hits a problem with enabled ref-verify, ignorebadroots and a fuzzed/damaged extent tree. There's no fallback option like in other places that can deal with it so disable the whole ref-verify as it is just a debugging feature. Reported-by: syzbot+9c3e0cdfbfe351b0bc0e@syzkaller.appspotmail.com Link: https://lore.kernel.org/all/0000000000001b6052062139be1c@google.com/ Reviewed-by: Qu Wenruo <wqu@suse.com> Signed-off-by: David Sterba <dsterba@suse.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
2025-10-02minmax: don't use max() in situations that want a C constant expressionLinus Torvalds1-1/+1
[ Upstream commit cb04e8b1d2f24c4c2c92f7b7529031fc35a16fed ] We only had a couple of array[] declarations, and changing them to just use 'MAX()' instead of 'max()' fixes the issue. This will allow us to simplify our min/max macros enormously, since they can now unconditionally use temporary variables to avoid using the argument values multiple times. Cc: David Laight <David.Laight@aculab.com> Cc: Lorenzo Stoakes <lorenzo.stoakes@oracle.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Eliav Farber <farbere@amazon.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2025-09-25btrfs: tree-checker: fix the incorrect inode ref size checkQu Wenruo1-2/+2
commit 96fa515e70f3e4b98685ef8cac9d737fc62f10e1 upstream. [BUG] Inside check_inode_ref(), we need to make sure every structure, including the btrfs_inode_extref header, is covered by the item. But our code is incorrectly using "sizeof(iref)", where @iref is just a pointer. This means "sizeof(iref)" will always be "sizeof(void *)", which is much smaller than "sizeof(struct btrfs_inode_extref)". This will allow some bad inode extrefs to sneak in, defeating tree-checker. [FIX] Fix the typo by calling "sizeof(*iref)", which is the same as "sizeof(struct btrfs_inode_extref)", and will be the correct behavior we want. Fixes: 71bf92a9b877 ("btrfs: tree-checker: Add check for INODE_REF") CC: stable@vger.kernel.org # 6.1+ Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com> Reviewed-by: Filipe Manana <fdmanana@suse.com> Signed-off-by: Qu Wenruo <wqu@suse.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2025-09-25btrfs: fix invalid extref key setup when replaying dentryFilipe Manana1-1/+1
[ Upstream commit b62fd63ade7cb573b114972ef8f9fa505be8d74a ] The offset for an extref item's key is not the object ID of the parent dir, otherwise we would not need the extref item and would use plain ref items. Instead the offset is the result of a hash computation that uses the object ID of the parent dir and the name associated to the entry. So fix this by setting the key offset at replay_one_name() to be the result of calling btrfs_extref_hash(). Fixes: 725af92a6251 ("btrfs: Open-code name_in_log_ref in replay_one_name") Signed-off-by: Filipe Manana <fdmanana@suse.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
2025-09-19btrfs: fix corruption reading compressed range when block size is smaller ↵Qu Wenruo1-14/+32
than page size [ Upstream commit 9786531399a679fc2f4630d2c0a186205282ab2f ] [BUG] With 64K page size (aarch64 with 64K page size config) and 4K btrfs block size, the following workload can easily lead to a corrupted read: mkfs.btrfs -f -s 4k $dev > /dev/null mount -o compress $dev $mnt xfs_io -f -c "pwrite -S 0xff 0 64k" $mnt/base > /dev/null echo "correct result:" od -Ad -t x1 $mnt/base xfs_io -f -c "reflink $mnt/base 32k 0 32k" \ -c "reflink $mnt/base 0 32k 32k" \ -c "pwrite -S 0xff 60k 4k" $mnt/new > /dev/null echo "incorrect result:" od -Ad -t x1 $mnt/new umount $mnt This shows the following result: correct result: 0000000 ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff * 0065536 incorrect result: 0000000 ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff * 0032768 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 * 0061440 ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff * 0065536 Notice the zero in the range [32K, 60K), which is incorrect. [CAUSE] With extra trace printk, it shows the following events during od: (some unrelated info removed like CPU and context) od-3457 btrfs_do_readpage: enter r/i=5/258 folio=0(65536) prev_em_start=0000000000000000 The "r/i" is indicating the root and inode number. In our case the file "new" is using ino 258 from fs tree (root 5). Here notice the @prev_em_start pointer is NULL. This means the btrfs_do_readpage() is called from btrfs_read_folio(), not from btrfs_readahead(). od-3457 btrfs_do_readpage: r/i=5/258 folio=0(65536) cur=0 got em start=0 len=32768 od-3457 btrfs_do_readpage: r/i=5/258 folio=0(65536) cur=4096 got em start=0 len=32768 od-3457 btrfs_do_readpage: r/i=5/258 folio=0(65536) cur=8192 got em start=0 len=32768 od-3457 btrfs_do_readpage: r/i=5/258 folio=0(65536) cur=12288 got em start=0 len=32768 od-3457 btrfs_do_readpage: r/i=5/258 folio=0(65536) cur=16384 got em start=0 len=32768 od-3457 btrfs_do_readpage: r/i=5/258 folio=0(65536) cur=20480 got em start=0 len=32768 od-3457 btrfs_do_readpage: r/i=5/258 folio=0(65536) cur=24576 got em start=0 len=32768 od-3457 btrfs_do_readpage: r/i=5/258 folio=0(65536) cur=28672 got em start=0 len=32768 These above 32K blocks will be read from the first half of the compressed data extent. od-3457 btrfs_do_readpage: r/i=5/258 folio=0(65536) cur=32768 got em start=32768 len=32768 Note here there is no btrfs_submit_compressed_read() call. Which is incorrect now. Although both extent maps at 0 and 32K are pointing to the same compressed data, their offsets are different thus can not be merged into the same read. So this means the compressed data read merge check is doing something wrong. od-3457 btrfs_do_readpage: r/i=5/258 folio=0(65536) cur=36864 got em start=32768 len=32768 od-3457 btrfs_do_readpage: r/i=5/258 folio=0(65536) cur=40960 got em start=32768 len=32768 od-3457 btrfs_do_readpage: r/i=5/258 folio=0(65536) cur=45056 got em start=32768 len=32768 od-3457 btrfs_do_readpage: r/i=5/258 folio=0(65536) cur=49152 got em start=32768 len=32768 od-3457 btrfs_do_readpage: r/i=5/258 folio=0(65536) cur=53248 got em start=32768 len=32768 od-3457 btrfs_do_readpage: r/i=5/258 folio=0(65536) cur=57344 got em start=32768 len=32768 od-3457 btrfs_do_readpage: r/i=5/258 folio=0(65536) cur=61440 skip uptodate od-3457 btrfs_submit_compressed_read: cb orig_bio: file off=0 len=61440 The function btrfs_submit_compressed_read() is only called at the end of folio read. The compressed bio will only have an extent map of range [0, 32K), but the original bio passed in is for the whole 64K folio. This will cause the decompression part to only fill the first 32K, leaving the rest untouched (aka, filled with zero). This incorrect compressed read merge leads to the above data corruption. There were similar problems that happened in the past, commit 808f80b46790 ("Btrfs: update fix for read corruption of compressed and shared extents") is doing pretty much the same fix for readahead. But that's back to 2015, where btrfs still only supports bs (block size) == ps (page size) cases. This means btrfs_do_readpage() only needs to handle a folio which contains exactly one block. Only btrfs_readahead() can lead to a read covering multiple blocks. Thus only btrfs_readahead() passes a non-NULL @prev_em_start pointer. With v5.15 kernel btrfs introduced bs < ps support. This breaks the above assumption that a folio can only contain one block. Now btrfs_read_folio() can also read multiple blocks in one go. But btrfs_read_folio() doesn't pass a @prev_em_start pointer, thus the existing bio force submission check will never be triggered. In theory, this can also happen for btrfs with large folios, but since large folio is still experimental, we don't need to bother it, thus only bs < ps support is affected for now. [FIX] Instead of passing @prev_em_start to do the proper compressed extent check, introduce one new member, btrfs_bio_ctrl::last_em_start, so that the existing bio force submission logic will always be triggered. CC: stable@vger.kernel.org # 5.15+ Reviewed-by: Filipe Manana <fdmanana@suse.com> Signed-off-by: Qu Wenruo <wqu@suse.com> Signed-off-by: David Sterba <dsterba@suse.com> Signed-off-by: Sasha Levin <sashal@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2025-09-19btrfs: use readahead_expand() on compressed extentsBoris Burkov1-1/+33
[ Upstream commit 9e9ff875e4174be939371667d2cc81244e31232f ] We recently received a report of poor performance doing sequential buffered reads of a file with compressed extents. With bs=128k, a naive sequential dd ran as fast on a compressed file as on an uncompressed (1.2GB/s on my reproducing system) while with bs<32k, this performance tanked down to ~300MB/s. i.e., slow: dd if=some-compressed-file of=/dev/null bs=4k count=X vs fast: dd if=some-compressed-file of=/dev/null bs=128k count=Y The cause of this slowness is overhead to do with looking up extent_maps to enable readahead pre-caching on compressed extents (add_ra_bio_pages()), as well as some overhead in the generic VFS readahead code we hit more in the slow case. Notably, the main difference between the two read sizes is that in the large sized request case, we call btrfs_readahead() relatively rarely while in the smaller request we call it for every compressed extent. So the fast case stays in the btrfs readahead loop: while ((folio = readahead_folio(rac)) != NULL) btrfs_do_readpage(folio, &em_cached, &bio_ctrl, &prev_em_start); where the slower one breaks out of that loop every time. This results in calling add_ra_bio_pages a lot, doing lots of extent_map lookups, extent_map locking, etc. This happens because although add_ra_bio_pages() does add the appropriate un-compressed file pages to the cache, it does not communicate back to the ractl in any way. To solve this, we should be using readahead_expand() to signal to readahead to expand the readahead window. This change passes the readahead_control into the btrfs_bio_ctrl and in the case of compressed reads sets the expansion to the size of the extent_map we already looked up anyway. It skips the subpage case as that one already doesn't do add_ra_bio_pages(). With this change, whether we use bs=4k or bs=128k, btrfs expands the readahead window up to the largest compressed extent we have seen so far (in the trivial example: 128k) and the call stacks of the two modes look identical. Notably, we barely call add_ra_bio_pages at all. And the performance becomes identical as well. So this change certainly "fixes" this performance problem. Of course, it does seem to beg a few questions: 1. Will this waste too much page cache with a too large ra window? 2. Will this somehow cause bugs prevented by the more thoughtful checking in add_ra_bio_pages? 3. Should we delete add_ra_bio_pages? My stabs at some answers: 1. Hard to say. See attempts at generic performance testing below. Is there a "readahead_shrink" we should be using? Should we expand more slowly, by half the remaining em size each time? 2. I don't think so. Since the new behavior is indistinguishable from reading the file with a larger read size passed in, I don't see why one would be safe but not the other. 3. Probably! I tested that and it was fine in fstests, and it seems like the pages would get re-used just as well in the readahead case. However, it is possible some reads that use page cache but not btrfs_readahead() could suffer. I will investigate this further as a follow up. I tested the performance implications of this change in 3 ways (using compress-force=zstd:3 for compression): Directly test the affected workload of small sequential reads on a compressed file (improved from ~250MB/s to ~1.2GB/s) ==========for-next========== dd /mnt/lol/non-cmpr 4k 1048576+0 records in 1048576+0 records out 4294967296 bytes (4.3 GB, 4.0 GiB) copied, 6.02983 s, 712 MB/s dd /mnt/lol/non-cmpr 128k 32768+0 records in 32768+0 records out 4294967296 bytes (4.3 GB, 4.0 GiB) copied, 5.92403 s, 725 MB/s dd /mnt/lol/cmpr 4k 1048576+0 records in 1048576+0 records out 4294967296 bytes (4.3 GB, 4.0 GiB) copied, 17.8832 s, 240 MB/s dd /mnt/lol/cmpr 128k 32768+0 records in 32768+0 records out 4294967296 bytes (4.3 GB, 4.0 GiB) copied, 3.71001 s, 1.2 GB/s ==========ra-expand========== dd /mnt/lol/non-cmpr 4k 1048576+0 records in 1048576+0 records out 4294967296 bytes (4.3 GB, 4.0 GiB) copied, 6.09001 s, 705 MB/s dd /mnt/lol/non-cmpr 128k 32768+0 records in 32768+0 records out 4294967296 bytes (4.3 GB, 4.0 GiB) copied, 6.07664 s, 707 MB/s dd /mnt/lol/cmpr 4k 1048576+0 records in 1048576+0 records out 4294967296 bytes (4.3 GB, 4.0 GiB) copied, 3.79531 s, 1.1 GB/s dd /mnt/lol/cmpr 128k 32768+0 records in 32768+0 records out 4294967296 bytes (4.3 GB, 4.0 GiB) copied, 3.69533 s, 1.2 GB/s Built the linux kernel from clean (no change) Ran fsperf. Mostly neutral results with some improvements and regressions here and there. Reported-by: Dimitrios Apostolou <jimis@gmx.net> Link: https://lore.kernel.org/linux-btrfs/34601559-6c16-6ccc-1793-20a97ca0dbba@gmx.net/ Reviewed-by: Filipe Manana <fdmanana@suse.com> Signed-off-by: Boris Burkov <boris@bur.io> Signed-off-by: David Sterba <dsterba@suse.com> Signed-off-by: Sasha Levin <sashal@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2025-09-09btrfs: adjust subpage bit start based on sectorsizeJosef Bacik1-1/+1
[ Upstream commit e08e49d986f82c30f42ad0ed43ebbede1e1e3739 ] When running machines with 64k page size and a 16k nodesize we started seeing tree log corruption in production. This turned out to be because we were not writing out dirty blocks sometimes, so this in fact affects all metadata writes. When writing out a subpage EB we scan the subpage bitmap for a dirty range. If the range isn't dirty we do bit_start++; to move onto the next bit. The problem is the bitmap is based on the number of sectors that an EB has. So in this case, we have a 64k pagesize, 16k nodesize, but a 4k sectorsize. This means our bitmap is 4 bits for every node. With a 64k page size we end up with 4 nodes per page. To make this easier this is how everything looks [0 16k 32k 48k ] logical address [0 4 8 12 ] radix tree offset [ 64k page ] folio [ 16k eb ][ 16k eb ][ 16k eb ][ 16k eb ] extent buffers [ | | | | | | | | | | | | | | | | ] bitmap Now we use all of our addressing based on fs_info->sectorsize_bits, so as you can see the above our 16k eb->start turns into radix entry 4. When we find a dirty range for our eb, we correctly do bit_start += sectors_per_node, because if we start at bit 0, the next bit for the next eb is 4, to correspond to eb->start 16k. However if our range is clean, we will do bit_start++, which will now put us offset from our radix tree entries. In our case, assume that the first time we check the bitmap the block is not dirty, we increment bit_start so now it == 1, and then we loop around and check again. This time it is dirty, and we go to find that start using the following equation start = folio_start + bit_start * fs_info->sectorsize; so in the case above, eb->start 0 is now dirty, and we calculate start as 0 + 1 * fs_info->sectorsize = 4096 4096 >> 12 = 1 Now we're looking up the radix tree for 1, and we won't find an eb. What's worse is now we're using bit_start == 1, so we do bit_start += sectors_per_node, which is now 5. If that eb is dirty we will run into the same thing, we will look at an offset that is not populated in the radix tree, and now we're skipping the writeout of dirty extent buffers. The best fix for this is to not use sectorsize_bits to address nodes, but that's a larger change. Since this is a fs corruption problem fix it simply by always using sectors_per_node to increment the start bit. Fixes: c4aec299fa8f ("btrfs: introduce submit_eb_subpage() to submit a subpage metadata page") CC: stable@vger.kernel.org # 5.15+ Reviewed-by: Boris Burkov <boris@bur.io> Reviewed-by: Qu Wenruo <wqu@suse.com> Signed-off-by: Josef Bacik <josef@toxicpanda.com> Signed-off-by: David Sterba <dsterba@suse.com> [ Adjust context ] Signed-off-by: Sasha Levin <sashal@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2025-09-09btrfs: avoid load/store tearing races when checking if an inode was loggedFilipe Manana1-4/+21
[ Upstream commit 986bf6ed44dff7fbae7b43a0882757ee7f5ba21b ] At inode_logged() we do a couple lockless checks for ->logged_trans, and these are generally safe except the second one in case we get a load or store tearing due to a concurrent call updating ->logged_trans (either at btrfs_log_inode() or later at inode_logged()). In the first case it's safe to compare to the current transaction ID since once ->logged_trans is set the current transaction, we never set it to a lower value. In the second case, where we check if it's greater than zero, we are prone to load/store tearing races, since we can have a concurrent task updating to the current transaction ID with store tearing for example, instead of updating with a single 64 bits write, to update with two 32 bits writes or four 16 bits writes. In that case the reading side at inode_logged() could see a positive value that does not match the current transaction and then return a false negative. Fix this by doing the second check while holding the inode's spinlock, add some comments about it too. Also add the data_race() annotation to the first check to avoid any reports from KCSAN (or similar tools) and comment about it. Fixes: 0f8ce49821de ("btrfs: avoid inode logging during rename and link when possible") Reviewed-by: Boris Burkov <boris@bur.io> Signed-off-by: Filipe Manana <fdmanana@suse.com> Signed-off-by: David Sterba <dsterba@suse.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
2025-09-09btrfs: fix race between setting last_dir_index_offset and inode loggingFilipe Manana3-16/+4
[ Upstream commit 59a0dd4ab98970086fd096281b1606c506ff2698 ] At inode_logged() if we find that the inode was not logged before we update its ->last_dir_index_offset to (u64)-1 with the goal that the next directory log operation will see the (u64)-1 and then figure out it must check what was the index of the last logged dir index key and update ->last_dir_index_offset to that key's offset (this is done in update_last_dir_index_offset()). This however has a possibility for a time window where a race can happen and lead to directory logging skipping dir index keys that should be logged. The race happens like this: 1) Task A calls inode_logged(), sees ->logged_trans as 0 and then checks that the inode item was logged before, but before it sets the inode's ->last_dir_index_offset to (u64)-1... 2) Task B is at btrfs_log_inode() which calls inode_logged() early, and that has set ->last_dir_index_offset to (u64)-1; 3) Task B then enters log_directory_changes() which calls update_last_dir_index_offset(). There it sees ->last_dir_index_offset is (u64)-1 and that the inode was logged before (ctx->logged_before is true), and so it searches for the last logged dir index key in the log tree and it finds that it has an offset (index) value of N, so it sets ->last_dir_index_offset to N, so that we can skip index keys that are less than or equal to N (later at process_dir_items_leaf()); 4) Task A now sets ->last_dir_index_offset to (u64)-1, undoing the update that task B just did; 5) Task B will now skip every index key when it enters process_dir_items_leaf(), since ->last_dir_index_offset is (u64)-1. Fix this by making inode_logged() not touch ->last_dir_index_offset and initializing it to 0 when an inode is loaded (at btrfs_alloc_inode()) and then having update_last_dir_index_offset() treat a value of 0 as meaning we must check the log tree and update with the index of the last logged index key. This is fine since the minimum possible value for ->last_dir_index_offset is 1 (BTRFS_DIR_START_INDEX - 1 = 2 - 1 = 1). This also simplifies the management of ->last_dir_index_offset and now all accesses to it are done under the inode's log_mutex. Fixes: 0f8ce49821de ("btrfs: avoid inode logging during rename and link when possible") Reviewed-by: Boris Burkov <boris@bur.io> Signed-off-by: Filipe Manana <fdmanana@suse.com> Signed-off-by: David Sterba <dsterba@suse.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
2025-09-09btrfs: fix race between logging inode and checking if it was logged beforeFilipe Manana1-6/+30
[ Upstream commit ef07b74e1be56f9eafda6aadebb9ebba0743c9f0 ] There's a race between checking if an inode was logged before and logging an inode that can cause us to mark an inode as not logged just after it was logged by a concurrent task: 1) We have inode X which was not logged before neither in the current transaction not in past transaction since the inode was loaded into memory, so it's ->logged_trans value is 0; 2) We are at transaction N; 3) Task A calls inode_logged() against inode X, sees that ->logged_trans is 0 and there is a log tree and so it proceeds to search in the log tree for an inode item for inode X. It doesn't see any, but before it sets ->logged_trans to N - 1... 3) Task B calls btrfs_log_inode() against inode X, logs the inode and sets ->logged_trans to N; 4) Task A now sets ->logged_trans to N - 1; 5) At this point anyone calling inode_logged() gets 0 (inode not logged) since ->logged_trans is greater than 0 and less than N, but our inode was really logged. As a consequence operations like rename, unlink and link that happen afterwards in the current transaction end up not updating the log when they should. Fix this by ensuring inode_logged() only updates ->logged_trans in case the inode item is not found in the log tree if after tacking the inode's lock (spinlock struct btrfs_inode::lock) the ->logged_trans value is still zero, since the inode lock is what protects setting ->logged_trans at btrfs_log_inode(). Fixes: 0f8ce49821de ("btrfs: avoid inode logging during rename and link when possible") Reviewed-by: Boris Burkov <boris@bur.io> Signed-off-by: Filipe Manana <fdmanana@suse.com> Signed-off-by: David Sterba <dsterba@suse.com> Signed-off-by: Sasha Levin <sashal@kernel.org>