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2024-12-06btrfs: flush delalloc workers queue before stopping cleaner kthread during ↵Filipe Manana
unmount During the unmount path, at close_ctree(), we first stop the cleaner kthread, using kthread_stop() which frees the associated task_struct, and then stop and destroy all the work queues. However after we stopped the cleaner we may still have a worker from the delalloc_workers queue running inode.c:submit_compressed_extents(), which calls btrfs_add_delayed_iput(), which in turn tries to wake up the cleaner kthread - which was already destroyed before, resulting in a use-after-free on the task_struct. Syzbot reported this with the following stack traces: BUG: KASAN: slab-use-after-free in __lock_acquire+0x78/0x2100 kernel/locking/lockdep.c:5089 Read of size 8 at addr ffff8880259d2818 by task kworker/u8:3/52 CPU: 1 UID: 0 PID: 52 Comm: kworker/u8:3 Not tainted 6.13.0-rc1-syzkaller-00002-gcdd30ebb1b9f #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024 Workqueue: btrfs-delalloc btrfs_work_helper Call Trace: <TASK> __dump_stack lib/dump_stack.c:94 [inline] dump_stack_lvl+0x241/0x360 lib/dump_stack.c:120 print_address_description mm/kasan/report.c:378 [inline] print_report+0x169/0x550 mm/kasan/report.c:489 kasan_report+0x143/0x180 mm/kasan/report.c:602 __lock_acquire+0x78/0x2100 kernel/locking/lockdep.c:5089 lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5849 __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline] _raw_spin_lock_irqsave+0xd5/0x120 kernel/locking/spinlock.c:162 class_raw_spinlock_irqsave_constructor include/linux/spinlock.h:551 [inline] try_to_wake_up+0xc2/0x1470 kernel/sched/core.c:4205 submit_compressed_extents+0xdf/0x16e0 fs/btrfs/inode.c:1615 run_ordered_work fs/btrfs/async-thread.c:288 [inline] btrfs_work_helper+0x96f/0xc40 fs/btrfs/async-thread.c:324 process_one_work kernel/workqueue.c:3229 [inline] process_scheduled_works+0xa66/0x1840 kernel/workqueue.c:3310 worker_thread+0x870/0xd30 kernel/workqueue.c:3391 kthread+0x2f0/0x390 kernel/kthread.c:389 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 </TASK> Allocated by task 2: kasan_save_stack mm/kasan/common.c:47 [inline] kasan_save_track+0x3f/0x80 mm/kasan/common.c:68 unpoison_slab_object mm/kasan/common.c:319 [inline] __kasan_slab_alloc+0x66/0x80 mm/kasan/common.c:345 kasan_slab_alloc include/linux/kasan.h:250 [inline] slab_post_alloc_hook mm/slub.c:4104 [inline] slab_alloc_node mm/slub.c:4153 [inline] kmem_cache_alloc_node_noprof+0x1d9/0x380 mm/slub.c:4205 alloc_task_struct_node kernel/fork.c:180 [inline] dup_task_struct+0x57/0x8c0 kernel/fork.c:1113 copy_process+0x5d1/0x3d50 kernel/fork.c:2225 kernel_clone+0x223/0x870 kernel/fork.c:2807 kernel_thread+0x1bc/0x240 kernel/fork.c:2869 create_kthread kernel/kthread.c:412 [inline] kthreadd+0x60d/0x810 kernel/kthread.c:767 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 Freed by task 24: kasan_save_stack mm/kasan/common.c:47 [inline] kasan_save_track+0x3f/0x80 mm/kasan/common.c:68 kasan_save_free_info+0x40/0x50 mm/kasan/generic.c:582 poison_slab_object mm/kasan/common.c:247 [inline] __kasan_slab_free+0x59/0x70 mm/kasan/common.c:264 kasan_slab_free include/linux/kasan.h:233 [inline] slab_free_hook mm/slub.c:2338 [inline] slab_free mm/slub.c:4598 [inline] kmem_cache_free+0x195/0x410 mm/slub.c:4700 put_task_struct include/linux/sched/task.h:144 [inline] delayed_put_task_struct+0x125/0x300 kernel/exit.c:227 rcu_do_batch kernel/rcu/tree.c:2567 [inline] rcu_core+0xaaa/0x17a0 kernel/rcu/tree.c:2823 handle_softirqs+0x2d4/0x9b0 kernel/softirq.c:554 run_ksoftirqd+0xca/0x130 kernel/softirq.c:943 smpboot_thread_fn+0x544/0xa30 kernel/smpboot.c:164 kthread+0x2f0/0x390 kernel/kthread.c:389 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 Last potentially related work creation: kasan_save_stack+0x3f/0x60 mm/kasan/common.c:47 __kasan_record_aux_stack+0xac/0xc0 mm/kasan/generic.c:544 __call_rcu_common kernel/rcu/tree.c:3086 [inline] call_rcu+0x167/0xa70 kernel/rcu/tree.c:3190 context_switch kernel/sched/core.c:5372 [inline] __schedule+0x1803/0x4be0 kernel/sched/core.c:6756 __schedule_loop kernel/sched/core.c:6833 [inline] schedule+0x14b/0x320 kernel/sched/core.c:6848 schedule_timeout+0xb0/0x290 kernel/time/sleep_timeout.c:75 do_wait_for_common kernel/sched/completion.c:95 [inline] __wait_for_common kernel/sched/completion.c:116 [inline] wait_for_common kernel/sched/completion.c:127 [inline] wait_for_completion+0x355/0x620 kernel/sched/completion.c:148 kthread_stop+0x19e/0x640 kernel/kthread.c:712 close_ctree+0x524/0xd60 fs/btrfs/disk-io.c:4328 generic_shutdown_super+0x139/0x2d0 fs/super.c:642 kill_anon_super+0x3b/0x70 fs/super.c:1237 btrfs_kill_super+0x41/0x50 fs/btrfs/super.c:2112 deactivate_locked_super+0xc4/0x130 fs/super.c:473 cleanup_mnt+0x41f/0x4b0 fs/namespace.c:1373 task_work_run+0x24f/0x310 kernel/task_work.c:239 ptrace_notify+0x2d2/0x380 kernel/signal.c:2503 ptrace_report_syscall include/linux/ptrace.h:415 [inline] ptrace_report_syscall_exit include/linux/ptrace.h:477 [inline] syscall_exit_work+0xc7/0x1d0 kernel/entry/common.c:173 syscall_exit_to_user_mode_prepare kernel/entry/common.c:200 [inline] __syscall_exit_to_user_mode_work kernel/entry/common.c:205 [inline] syscall_exit_to_user_mode+0x24a/0x340 kernel/entry/common.c:218 do_syscall_64+0x100/0x230 arch/x86/entry/common.c:89 entry_SYSCALL_64_after_hwframe+0x77/0x7f The buggy address belongs to the object at ffff8880259d1e00 which belongs to the cache task_struct of size 7424 The buggy address is located 2584 bytes inside of freed 7424-byte region [ffff8880259d1e00, ffff8880259d3b00) The buggy address belongs to the physical page: page: refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x259d0 head: order:3 mapcount:0 entire_mapcount:0 nr_pages_mapped:0 pincount:0 memcg:ffff88802f4b56c1 flags: 0xfff00000000040(head|node=0|zone=1|lastcpupid=0x7ff) page_type: f5(slab) raw: 00fff00000000040 ffff88801bafe500 dead000000000100 dead000000000122 raw: 0000000000000000 0000000000040004 00000001f5000000 ffff88802f4b56c1 head: 00fff00000000040 ffff88801bafe500 dead000000000100 dead000000000122 head: 0000000000000000 0000000000040004 00000001f5000000 ffff88802f4b56c1 head: 00fff00000000003 ffffea0000967401 ffffffffffffffff 0000000000000000 head: 0000000000000008 0000000000000000 00000000ffffffff 0000000000000000 page dumped because: kasan: bad access detected page_owner tracks the page as allocated page last allocated via order 3, migratetype Unmovable, gfp_mask 0xd20c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 12, tgid 12 (kworker/u8:1), ts 7328037942, free_ts 0 set_page_owner include/linux/page_owner.h:32 [inline] post_alloc_hook+0x1f3/0x230 mm/page_alloc.c:1556 prep_new_page mm/page_alloc.c:1564 [inline] get_page_from_freelist+0x3651/0x37a0 mm/page_alloc.c:3474 __alloc_pages_noprof+0x292/0x710 mm/page_alloc.c:4751 alloc_pages_mpol_noprof+0x3e8/0x680 mm/mempolicy.c:2265 alloc_slab_page+0x6a/0x140 mm/slub.c:2408 allocate_slab+0x5a/0x2f0 mm/slub.c:2574 new_slab mm/slub.c:2627 [inline] ___slab_alloc+0xcd1/0x14b0 mm/slub.c:3815 __slab_alloc+0x58/0xa0 mm/slub.c:3905 __slab_alloc_node mm/slub.c:3980 [inline] slab_alloc_node mm/slub.c:4141 [inline] kmem_cache_alloc_node_noprof+0x269/0x380 mm/slub.c:4205 alloc_task_struct_node kernel/fork.c:180 [inline] dup_task_struct+0x57/0x8c0 kernel/fork.c:1113 copy_process+0x5d1/0x3d50 kernel/fork.c:2225 kernel_clone+0x223/0x870 kernel/fork.c:2807 user_mode_thread+0x132/0x1a0 kernel/fork.c:2885 call_usermodehelper_exec_work+0x5c/0x230 kernel/umh.c:171 process_one_work kernel/workqueue.c:3229 [inline] process_scheduled_works+0xa66/0x1840 kernel/workqueue.c:3310 worker_thread+0x870/0xd30 kernel/workqueue.c:3391 page_owner free stack trace missing Memory state around the buggy address: ffff8880259d2700: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff8880259d2780: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff8880259d2800: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff8880259d2880: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff8880259d2900: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ================================================================== Fix this by flushing the delalloc workers queue before stopping the cleaner kthread. Reported-by: syzbot+b7cf50a0c173770dcb14@syzkaller.appspotmail.com Link: https://lore.kernel.org/linux-btrfs/674ed7e8.050a0220.48a03.0031.GAE@google.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>
2024-11-11btrfs: remove fs_info parameter from btrfs_cleanup_one_transaction()Filipe Manana
The fs_info parameter is redundant because it can be extracted from the transaction given as another parameter. So remove it and use the fs_info accessible from the transaction. Reviewed-by: Boris Burkov <boris@bur.io> 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>
2024-11-11btrfs: remove fs_info parameter from btrfs_destroy_delayed_refs()Filipe Manana
The fs_info parameter is redundant because it can be extracted from the transaction given as another parameter. So remove it and use the fs_info accessible from the transaction. Reviewed-by: Boris Burkov <boris@bur.io> 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>
2024-11-11btrfs: move btrfs_destroy_delayed_refs() to delayed-ref.cFilipe Manana
It's better suited at delayed-ref.c since it's about delayed refs and contains logic to iterate over them (using the red black tree, doing all the locking, freeing, etc), so move it from disk-io.c, which is pretty big, into delayed-ref.c, hiding implementation details of how delayed refs are tracked and managed. This also facilitates the next patches in the series. This change moves the code between files but also does the following simple cleanups: 1) Rename the 'cache' variable to 'bg', since it's a block group (the 'cache' logic comes from old days where the block group structure was named 'btrfs_block_group_cache'); 2) Move the 'ref' variable declaration to the scope of the inner while loop, since it's not used outside that loop. Reviewed-by: Boris Burkov <boris@bur.io> 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>
2024-11-11btrfs: remove BUG_ON() at btrfs_destroy_delayed_refs()Filipe Manana
At btrfs_destroy_delayed_refs() it's unexpected to not find the block group to which a delayed reference's extent belongs to, so we have this BUG_ON(), not just because it's highly unexpected but also because we don't know what to do there. Since we are in the transaction abort path, there's nothing we can do other than proceed and cleanup all used resources we can. So remove the BUG_ON() and deal with a missing block group by logging an error message and continuing to cleanup all we can related to the current delayed ref head and moving to other delayed refs. Reviewed-by: Boris Burkov <boris@bur.io> 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>
2024-11-11btrfs: rename extent map shrinker members from struct btrfs_fs_infoFilipe Manana
The names for the members of struct btrfs_fs_info related to the extent map shrinker are a bit too long, so rename them to be shorter by replacing the "extent_map_" prefix with the "em_" prefix. Reviewed-by: Josef Bacik <josef@toxicpanda.com> Signed-off-by: Filipe Manana <fdmanana@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2024-11-11btrfs: simplify tracking progress for the extent map shrinkerFilipe Manana
Now that the extent map shrinker can only be run by a single task (as a work queue item) there is no need to keep the progress of the shrinker protected by a spinlock and passing the progress to trace events as parameters. So remove the lock and simplify the arguments for the trace events. Reviewed-by: Josef Bacik <josef@toxicpanda.com> Signed-off-by: Filipe Manana <fdmanana@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2024-11-11btrfs: make the extent map shrinker run asynchronously as a work queue jobFilipe Manana
Currently the extent map shrinker is run synchronously for kswapd tasks that end up calling the fs shrinker (fs/super.c:super_cache_scan()). This has some disadvantages and for some heavy workloads with memory pressure it can cause some delays and stalls that make a machine unresponsive for some periods. This happens because: 1) We can have several kswapd tasks on machines with multiple NUMA zones, and running the extent map shrinker concurrently can cause high contention on some spin locks, namely the spin locks that protect the radix tree that tracks roots, the per root xarray that tracks open inodes and the list of delayed iputs. This not only delays the shrinker but also causes high CPU consumption and makes the task running the shrinker monopolize a core, resulting in the symptoms of an unresponsive system. This was noted in previous commits such as commit ae1e766f623f ("btrfs: only run the extent map shrinker from kswapd tasks"); 2) The extent map shrinker's iteration over inodes can often be slow, even after changing the data structure that tracks open inodes for a root from a red black tree (up to kernel 6.10) to an xarray (kernel 6.10+). The transition to the xarray while it made things a bit faster, it's still somewhat slow - for example in a test scenario with 10000 inodes that have no extent maps loaded, the extent map shrinker took between 5ms to 8ms, using a release, non-debug kernel. Iterating over the extent maps of an inode can also be slow if have an inode with many thousands of extent maps, since we use a red black tree to track and search extent maps. So having the extent map shrinker run synchronously adds extra delay for other things a kswapd task does. So make the extent map shrinker run asynchronously as a job for the system unbounded workqueue, just like what we do for data and metadata space reclaim jobs. Reviewed-by: Josef Bacik <josef@toxicpanda.com> Signed-off-by: Filipe Manana <fdmanana@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2024-11-11btrfs: drop unused parameter transaction from alloc_log_tree()David Sterba
The function got split in commit 6ab6ebb76042d3 ("btrfs: split alloc_log_tree()") and since then transaction parameter has been unused. Reviewed-by: Anand Jain <anand.jain@oracle.com> Signed-off-by: David Sterba <dsterba@suse.com>
2024-11-11btrfs: drop unused parameter options from open_ctree()David Sterba
Since the new mount option parser in commit ad21f15b0f79 ("btrfs: switch to the new mount API") we don't pass the options like that anymore. Reviewed-by: Anand Jain <anand.jain@oracle.com> Signed-off-by: David Sterba <dsterba@suse.com>
2024-10-24Merge tag 'for-6.12-rc4-tag' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux Pull btrfs fixes from David Sterba: - mount option fixes: - fix handling of compression mount options on remount - reject rw remount in case there are options that don't work in read-write mode (like rescue options) - fix zone accounting of unusable space - fix in-memory corruption when merging extent maps - fix delalloc range locking for sector < page - use more convenient default value of drop subtree threshold, clean more subvolumes without the fallback to marking quotas inconsistent - fix smatch warning about incorrect value passed to ERR_PTR * tag 'for-6.12-rc4-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux: btrfs: fix passing 0 to ERR_PTR in btrfs_search_dir_index_item() btrfs: reject ro->rw reconfiguration if there are hard ro requirements btrfs: fix read corruption due to race with extent map merging btrfs: fix the delalloc range locking if sector size < page size btrfs: qgroup: set a more sane default value for subtree drop threshold btrfs: clear force-compress on remount when compress mount option is given btrfs: zoned: fix zone unusable accounting for freed reserved extent
2024-10-22btrfs: qgroup: set a more sane default value for subtree drop thresholdQu Wenruo
Since commit 011b46c30476 ("btrfs: skip subtree scan if it's too high to avoid low stall in btrfs_commit_transaction()"), btrfs qgroup can automatically skip large subtree scan at the cost of marking qgroup inconsistent. It's designed to address the final performance problem of snapshot drop with qgroup enabled, but to be safe the default value is BTRFS_MAX_LEVEL, requiring a user space daemon to set a different value to make it work. I'd say it's not a good idea to rely on user space tool to set this default value, especially when some operations (snapshot dropping) can be triggered immediately after mount, leaving a very small window to that that sysfs interface. So instead of disabling this new feature by default, enable it with a low threshold (3), so that large subvolume tree drop at mount time won't cause huge qgroup workload. CC: stable@vger.kernel.org # 6.1 Signed-off-by: Qu Wenruo <wqu@suse.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2024-10-04Merge tag 'for-6.12-rc1-tag' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux Pull btrfs fixes from David Sterba: - in incremental send, fix invalid clone operation for file that got its size decreased - fix __counted_by() annotation of send path cache entries, we do not store the terminating NUL - fix a longstanding bug in relocation (and quite hard to hit by chance), drop back reference cache that can get out of sync after transaction commit - wait for fixup worker kthread before finishing umount - add missing raid-stripe-tree extent for NOCOW files, zoned mode cannot have NOCOW files but RST is meant to be a standalone feature - handle transaction start error during relocation, avoid potential NULL pointer dereference of relocation control structure (reported by syzbot) - disable module-wide rate limiting of debug level messages - minor fix to tracepoint definition (reported by checkpatch.pl) * tag 'for-6.12-rc1-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux: btrfs: disable rate limiting when debug enabled btrfs: wait for fixup workers before stopping cleaner kthread during umount btrfs: fix a NULL pointer dereference when failed to start a new trasacntion btrfs: send: fix invalid clone operation for file that got its size decreased btrfs: tracepoints: end assignment with semicolon at btrfs_qgroup_extent event class btrfs: drop the backref cache during relocation if we commit btrfs: also add stripe entries for NOCOW writes btrfs: send: fix buffer overflow detection when copying path to cache entry
2024-10-02move asm/unaligned.h to linux/unaligned.hAl Viro
asm/unaligned.h is always an include of asm-generic/unaligned.h; might as well move that thing to linux/unaligned.h and include that - there's nothing arch-specific in that header. auto-generated by the following: for i in `git grep -l -w asm/unaligned.h`; do sed -i -e "s/asm\/unaligned.h/linux\/unaligned.h/" $i done for i in `git grep -l -w asm-generic/unaligned.h`; do sed -i -e "s/asm-generic\/unaligned.h/linux\/unaligned.h/" $i done git mv include/asm-generic/unaligned.h include/linux/unaligned.h git mv tools/include/asm-generic/unaligned.h tools/include/linux/unaligned.h sed -i -e "/unaligned.h/d" include/asm-generic/Kbuild sed -i -e "s/__ASM_GENERIC/__LINUX/" include/linux/unaligned.h tools/include/linux/unaligned.h
2024-10-01btrfs: wait for fixup workers before stopping cleaner kthread during umountFilipe Manana
During unmount, at close_ctree(), we have the following steps in this order: 1) Park the cleaner kthread - this doesn't destroy the kthread, it basically halts its execution (wake ups against it work but do nothing); 2) We stop the cleaner kthread - this results in freeing the respective struct task_struct; 3) We call btrfs_stop_all_workers() which waits for any jobs running in all the work queues and then free the work queues. Syzbot reported a case where a fixup worker resulted in a crash when doing a delayed iput on its inode while attempting to wake up the cleaner at btrfs_add_delayed_iput(), because the task_struct of the cleaner kthread was already freed. This can happen during unmount because we don't wait for any fixup workers still running before we call kthread_stop() against the cleaner kthread, which stops and free all its resources. Fix this by waiting for any fixup workers at close_ctree() before we call kthread_stop() against the cleaner and run pending delayed iputs. The stack traces reported by syzbot were the following: BUG: KASAN: slab-use-after-free in __lock_acquire+0x77/0x2050 kernel/locking/lockdep.c:5065 Read of size 8 at addr ffff8880272a8a18 by task kworker/u8:3/52 CPU: 1 UID: 0 PID: 52 Comm: kworker/u8:3 Not tainted 6.12.0-rc1-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024 Workqueue: btrfs-fixup btrfs_work_helper Call Trace: <TASK> __dump_stack lib/dump_stack.c:94 [inline] dump_stack_lvl+0x241/0x360 lib/dump_stack.c:120 print_address_description mm/kasan/report.c:377 [inline] print_report+0x169/0x550 mm/kasan/report.c:488 kasan_report+0x143/0x180 mm/kasan/report.c:601 __lock_acquire+0x77/0x2050 kernel/locking/lockdep.c:5065 lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5825 __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline] _raw_spin_lock_irqsave+0xd5/0x120 kernel/locking/spinlock.c:162 class_raw_spinlock_irqsave_constructor include/linux/spinlock.h:551 [inline] try_to_wake_up+0xb0/0x1480 kernel/sched/core.c:4154 btrfs_writepage_fixup_worker+0xc16/0xdf0 fs/btrfs/inode.c:2842 btrfs_work_helper+0x390/0xc50 fs/btrfs/async-thread.c:314 process_one_work kernel/workqueue.c:3229 [inline] process_scheduled_works+0xa63/0x1850 kernel/workqueue.c:3310 worker_thread+0x870/0xd30 kernel/workqueue.c:3391 kthread+0x2f0/0x390 kernel/kthread.c:389 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 </TASK> Allocated by task 2: kasan_save_stack mm/kasan/common.c:47 [inline] kasan_save_track+0x3f/0x80 mm/kasan/common.c:68 unpoison_slab_object mm/kasan/common.c:319 [inline] __kasan_slab_alloc+0x66/0x80 mm/kasan/common.c:345 kasan_slab_alloc include/linux/kasan.h:247 [inline] slab_post_alloc_hook mm/slub.c:4086 [inline] slab_alloc_node mm/slub.c:4135 [inline] kmem_cache_alloc_node_noprof+0x16b/0x320 mm/slub.c:4187 alloc_task_struct_node kernel/fork.c:180 [inline] dup_task_struct+0x57/0x8c0 kernel/fork.c:1107 copy_process+0x5d1/0x3d50 kernel/fork.c:2206 kernel_clone+0x223/0x880 kernel/fork.c:2787 kernel_thread+0x1bc/0x240 kernel/fork.c:2849 create_kthread kernel/kthread.c:412 [inline] kthreadd+0x60d/0x810 kernel/kthread.c:765 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 Freed by task 61: kasan_save_stack mm/kasan/common.c:47 [inline] kasan_save_track+0x3f/0x80 mm/kasan/common.c:68 kasan_save_free_info+0x40/0x50 mm/kasan/generic.c:579 poison_slab_object mm/kasan/common.c:247 [inline] __kasan_slab_free+0x59/0x70 mm/kasan/common.c:264 kasan_slab_free include/linux/kasan.h:230 [inline] slab_free_hook mm/slub.c:2343 [inline] slab_free mm/slub.c:4580 [inline] kmem_cache_free+0x1a2/0x420 mm/slub.c:4682 put_task_struct include/linux/sched/task.h:144 [inline] delayed_put_task_struct+0x125/0x300 kernel/exit.c:228 rcu_do_batch kernel/rcu/tree.c:2567 [inline] rcu_core+0xaaa/0x17a0 kernel/rcu/tree.c:2823 handle_softirqs+0x2c5/0x980 kernel/softirq.c:554 __do_softirq kernel/softirq.c:588 [inline] invoke_softirq kernel/softirq.c:428 [inline] __irq_exit_rcu+0xf4/0x1c0 kernel/softirq.c:637 irq_exit_rcu+0x9/0x30 kernel/softirq.c:649 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1037 [inline] sysvec_apic_timer_interrupt+0xa6/0xc0 arch/x86/kernel/apic/apic.c:1037 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702 Last potentially related work creation: kasan_save_stack+0x3f/0x60 mm/kasan/common.c:47 __kasan_record_aux_stack+0xac/0xc0 mm/kasan/generic.c:541 __call_rcu_common kernel/rcu/tree.c:3086 [inline] call_rcu+0x167/0xa70 kernel/rcu/tree.c:3190 context_switch kernel/sched/core.c:5318 [inline] __schedule+0x184b/0x4ae0 kernel/sched/core.c:6675 schedule_idle+0x56/0x90 kernel/sched/core.c:6793 do_idle+0x56a/0x5d0 kernel/sched/idle.c:354 cpu_startup_entry+0x42/0x60 kernel/sched/idle.c:424 start_secondary+0x102/0x110 arch/x86/kernel/smpboot.c:314 common_startup_64+0x13e/0x147 The buggy address belongs to the object at ffff8880272a8000 which belongs to the cache task_struct of size 7424 The buggy address is located 2584 bytes inside of freed 7424-byte region [ffff8880272a8000, ffff8880272a9d00) The buggy address belongs to the physical page: page: refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x272a8 head: order:3 mapcount:0 entire_mapcount:0 nr_pages_mapped:0 pincount:0 flags: 0xfff00000000040(head|node=0|zone=1|lastcpupid=0x7ff) page_type: f5(slab) raw: 00fff00000000040 ffff88801bafa500 dead000000000122 0000000000000000 raw: 0000000000000000 0000000080040004 00000001f5000000 0000000000000000 head: 00fff00000000040 ffff88801bafa500 dead000000000122 0000000000000000 head: 0000000000000000 0000000080040004 00000001f5000000 0000000000000000 head: 00fff00000000003 ffffea00009caa01 ffffffffffffffff 0000000000000000 head: 0000000000000008 0000000000000000 00000000ffffffff 0000000000000000 page dumped because: kasan: bad access detected page_owner tracks the page as allocated page last allocated via order 3, migratetype Unmovable, gfp_mask 0xd20c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 2, tgid 2 (kthreadd), ts 71247381401, free_ts 71214998153 set_page_owner include/linux/page_owner.h:32 [inline] post_alloc_hook+0x1f3/0x230 mm/page_alloc.c:1537 prep_new_page mm/page_alloc.c:1545 [inline] get_page_from_freelist+0x3039/0x3180 mm/page_alloc.c:3457 __alloc_pages_noprof+0x256/0x6c0 mm/page_alloc.c:4733 alloc_pages_mpol_noprof+0x3e8/0x680 mm/mempolicy.c:2265 alloc_slab_page+0x6a/0x120 mm/slub.c:2413 allocate_slab+0x5a/0x2f0 mm/slub.c:2579 new_slab mm/slub.c:2632 [inline] ___slab_alloc+0xcd1/0x14b0 mm/slub.c:3819 __slab_alloc+0x58/0xa0 mm/slub.c:3909 __slab_alloc_node mm/slub.c:3962 [inline] slab_alloc_node mm/slub.c:4123 [inline] kmem_cache_alloc_node_noprof+0x1fe/0x320 mm/slub.c:4187 alloc_task_struct_node kernel/fork.c:180 [inline] dup_task_struct+0x57/0x8c0 kernel/fork.c:1107 copy_process+0x5d1/0x3d50 kernel/fork.c:2206 kernel_clone+0x223/0x880 kernel/fork.c:2787 kernel_thread+0x1bc/0x240 kernel/fork.c:2849 create_kthread kernel/kthread.c:412 [inline] kthreadd+0x60d/0x810 kernel/kthread.c:765 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 page last free pid 5230 tgid 5230 stack trace: reset_page_owner include/linux/page_owner.h:25 [inline] free_pages_prepare mm/page_alloc.c:1108 [inline] free_unref_page+0xcd0/0xf00 mm/page_alloc.c:2638 discard_slab mm/slub.c:2678 [inline] __put_partials+0xeb/0x130 mm/slub.c:3146 put_cpu_partial+0x17c/0x250 mm/slub.c:3221 __slab_free+0x2ea/0x3d0 mm/slub.c:4450 qlink_free mm/kasan/quarantine.c:163 [inline] qlist_free_all+0x9a/0x140 mm/kasan/quarantine.c:179 kasan_quarantine_reduce+0x14f/0x170 mm/kasan/quarantine.c:286 __kasan_slab_alloc+0x23/0x80 mm/kasan/common.c:329 kasan_slab_alloc include/linux/kasan.h:247 [inline] slab_post_alloc_hook mm/slub.c:4086 [inline] slab_alloc_node mm/slub.c:4135 [inline] kmem_cache_alloc_noprof+0x135/0x2a0 mm/slub.c:4142 getname_flags+0xb7/0x540 fs/namei.c:139 do_sys_openat2+0xd2/0x1d0 fs/open.c:1409 do_sys_open fs/open.c:1430 [inline] __do_sys_openat fs/open.c:1446 [inline] __se_sys_openat fs/open.c:1441 [inline] __x64_sys_openat+0x247/0x2a0 fs/open.c:1441 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f Memory state around the buggy address: ffff8880272a8900: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff8880272a8980: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff8880272a8a00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff8880272a8a80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff8880272a8b00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ================================================================== Reported-by: syzbot+8aaf2df2ef0164ffe1fb@syzkaller.appspotmail.com Link: https://lore.kernel.org/linux-btrfs/66fb36b1.050a0220.aab67.003b.GAE@google.com/ CC: stable@vger.kernel.org # 4.19+ Reviewed-by: Qu Wenruo <wqu@suse.com> Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com> Reviewed-by: David Sterba <dsterba@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>
2024-09-10btrfs: convert try_release_extent_buffer() to take a folioLi Zetao
The old page API is being gradually replaced and converted to use folio to improve code readability and avoid repeated conversion between page and folio. Signed-off-by: Li Zetao <lizetao1@huawei.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2024-09-10btrfs: subpage: remove btrfs_fs_info::subpage_info memberQu Wenruo
The member btrfs_fs_info::subpage_info stores the cached bitmap start position inside the merged bitmap. However in reality there is only one thing depending on the sectorsize, bitmap_nr_bits, which records the number of sectors that fit inside a page. The sequence of sub-bitmaps have fixed order, thus it's just a quick multiplication to calculate the start position of each sub-bitmaps. Signed-off-by: Qu Wenruo <wqu@suse.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2024-07-17Merge tag 'for-6.11-tag' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux Pull btrfs updates from David Sterba: "The highlights are new logic behind background block group reclaim, automatic removal of qgroup after removing a subvolume and new 'rescue=' mount options. The rest is optimizations, cleanups and refactoring. User visible features: - dynamic block group reclaim: - tunable framework to avoid situations where eager data allocations prevent creating new metadata chunks due to lack of unallocated space - reuse sysfs knob bg_reclaim_threshold (otherwise used only in zoned mode) for a fixed value threshold - new on/off sysfs knob "dynamic_reclaim" calculating the value based on heuristics, aiming to keep spare working space for relocating chunks but not to needlessly relocate partially utilized block groups or reclaim newly allocated ones - stats are exported in sysfs per block group type, files "reclaim_*" - this may increase IO load at unexpected times but the corner case of no allocatable block groups is known to be worse - automatically remove qgroup of deleted subvolumes: - adjust qgroup removal conditions, make sure all related subvolume data are already removed, or return EBUSY, also take into account setting of sysfs drop_subtree_threshold - also works in squota mode - mount option updates: new modes of 'rescue=' that allow to mount images (read-only) that could have been partially converted by user space tools - ignoremetacsums - invalid metadata checksums are ignored - ignoresuperflags - super block flags that track conversion in progress (like UUID or checksums) Core: - size of struct btrfs_inode is now below 1024 (on a release config), improved memory packing and other secondary effects - switch tracking of open inodes from rb-tree to xarray, minor performance improvement - reduce number of empty transaction commits when there are no dirty data/metadata - memory allocation optimizations (reduced numbers, reordering out of critical sections) - extent map structure optimizations and refactoring, more sanity checks - more subpage in zoned mode preparations or fixes - general snapshot code cleanups, improvements and documentation - tree-checker updates: more file extent ram_bytes fixes, continued - raid-stripe-tree update (not backward compatible): - remove extent encoding field from the structure, can be inferred from other information - requires btrfs-progs 6.9.1 or newer - cleanups and refactoring - error message updates - error handling improvements - return type and parameter cleanups and improvements" * tag 'for-6.11-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux: (152 commits) btrfs: fix extent map use-after-free when adding pages to compressed bio btrfs: fix bitmap leak when loading free space cache on duplicate entry btrfs: remove the BUG_ON() inside extent_range_clear_dirty_for_io() btrfs: move extent_range_clear_dirty_for_io() into inode.c btrfs: enhance compression error messages btrfs: fix data race when accessing the last_trans field of a root btrfs: rename the extra_gfp parameter of btrfs_alloc_page_array() btrfs: remove the extra_gfp parameter from btrfs_alloc_folio_array() btrfs: introduce new "rescue=ignoresuperflags" mount option btrfs: introduce new "rescue=ignoremetacsums" mount option btrfs: output the unrecognized super block flags as hex btrfs: remove unused Opt enums btrfs: tree-checker: add extra ram_bytes and disk_num_bytes check btrfs: fix the ram_bytes assignment for truncated ordered extents btrfs: make validate_extent_map() catch ram_bytes mismatch btrfs: ignore incorrect btrfs_file_extent_item::ram_bytes btrfs: cleanup the bytenr usage inside btrfs_extent_item_to_extent_map() btrfs: fix typo in error message in btrfs_validate_super() btrfs: move the direct IO code into its own file btrfs: pass a btrfs_inode to btrfs_set_prop() ...
2024-07-12Merge tag 'for-6.10-rc7-tag' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux Pull btrfs fixes from David Sterba: "Fix a regression in extent map shrinker behaviour. In the past weeks we got reports from users that there are huge latency spikes or freezes. This was bisected to newly added shrinker of extent maps (it was added to fix a build up of the structures in memory). I'm assuming that the freezes would happen to many users after release so I'd like to get it merged now so it's in 6.10. Although the diff size is not small the changes are relatively straightforward, the reporters verified the fixes and we did testing on our side. The fixes: - adjust behaviour under memory pressure and check lock or scheduling conditions, bail out if needed - synchronize tracking of the scanning progress so inode ranges are not skipped or work duplicated - do a delayed iput when scanning a root so evicting an inode does not slow things down in case of lots of dirty data, also fix lockdep warning, a deadlock could happen when writing the dirty data would need to start a transaction" * tag 'for-6.10-rc7-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux: btrfs: avoid races when tracking progress for extent map shrinking btrfs: stop extent map shrinker if reschedule is needed btrfs: use delayed iput during extent map shrinking
2024-07-11btrfs: avoid races when tracking progress for extent map shrinkingFilipe Manana
We store the progress (root and inode numbers) of the extent map shrinker in fs_info without any synchronization but we can have multiple tasks calling into the shrinker during memory allocations when there's enough memory pressure for example. This can result in a task A reading fs_info->extent_map_shrinker_last_ino after another task B updates it, and task A reading fs_info->extent_map_shrinker_last_root before task B updates it, making task A see an odd state that isn't necessarily harmful but may make it skip certain inode ranges or do more work than necessary by going over the same inodes again. These unprotected accesses would also trigger warnings from tools like KCSAN. So add a lock to protect access to these progress fields. Reviewed-by: Josef Bacik <josef@toxicpanda.com> Signed-off-by: Filipe Manana <fdmanana@suse.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2024-07-11btrfs: fix data race when accessing the last_trans field of a rootFilipe Manana
KCSAN complains about a data race when accessing the last_trans field of a root: [ 199.553628] BUG: KCSAN: data-race in btrfs_record_root_in_trans [btrfs] / record_root_in_trans [btrfs] [ 199.555186] read to 0x000000008801e308 of 8 bytes by task 2812 on cpu 1: [ 199.555210] btrfs_record_root_in_trans+0x9a/0x128 [btrfs] [ 199.555999] start_transaction+0x154/0xcd8 [btrfs] [ 199.556780] btrfs_join_transaction+0x44/0x60 [btrfs] [ 199.557559] btrfs_dirty_inode+0x9c/0x140 [btrfs] [ 199.558339] btrfs_update_time+0x8c/0xb0 [btrfs] [ 199.559123] touch_atime+0x16c/0x1e0 [ 199.559151] pipe_read+0x6a8/0x7d0 [ 199.559179] vfs_read+0x466/0x498 [ 199.559204] ksys_read+0x108/0x150 [ 199.559230] __s390x_sys_read+0x68/0x88 [ 199.559257] do_syscall+0x1c6/0x210 [ 199.559286] __do_syscall+0xc8/0xf0 [ 199.559318] system_call+0x70/0x98 [ 199.559431] write to 0x000000008801e308 of 8 bytes by task 2808 on cpu 0: [ 199.559464] record_root_in_trans+0x196/0x228 [btrfs] [ 199.560236] btrfs_record_root_in_trans+0xfe/0x128 [btrfs] [ 199.561097] start_transaction+0x154/0xcd8 [btrfs] [ 199.561927] btrfs_join_transaction+0x44/0x60 [btrfs] [ 199.562700] btrfs_dirty_inode+0x9c/0x140 [btrfs] [ 199.563493] btrfs_update_time+0x8c/0xb0 [btrfs] [ 199.564277] file_update_time+0xb8/0xf0 [ 199.564301] pipe_write+0x8ac/0xab8 [ 199.564326] vfs_write+0x33c/0x588 [ 199.564349] ksys_write+0x108/0x150 [ 199.564372] __s390x_sys_write+0x68/0x88 [ 199.564397] do_syscall+0x1c6/0x210 [ 199.564424] __do_syscall+0xc8/0xf0 [ 199.564452] system_call+0x70/0x98 This is because we update and read last_trans concurrently without any type of synchronization. This should be generally harmless and in the worst case it can make us do extra locking (btrfs_record_root_in_trans()) trigger some warnings at ctree.c or do extra work during relocation - this would probably only happen in case of load or store tearing. So fix this by always reading and updating the field using READ_ONCE() and WRITE_ONCE(), this silences KCSAN and prevents load and store tearing. Reviewed-by: Josef Bacik <josef@toxicpanda.com> Signed-off-by: Filipe Manana <fdmanana@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2024-07-11btrfs: introduce new "rescue=ignoresuperflags" mount optionQu Wenruo
This new mount option allows the kernel to skip the super flags check, it's mostly to allow the kernel to do a rescue mount of an interrupted checksum conversion. Reviewed-by: Josef Bacik <josef@toxicpanda.com> Signed-off-by: Qu Wenruo <wqu@suse.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2024-07-11btrfs: introduce new "rescue=ignoremetacsums" mount optionQu Wenruo
Introduce "rescue=ignoremetacsums" to ignore metadata csums, all the other metadata sanity checks are still kept as is. This new mount option is mostly to allow the kernel to mount an interrupted checksum conversion (at the metadata csum overwrite stage). And since the main part of metadata sanity checks is inside tree-checker, we shouldn't lose much safety, and the new mount option is rescue mount option it requires full read-only mount. Reviewed-by: Josef Bacik <josef@toxicpanda.com> Signed-off-by: Qu Wenruo <wqu@suse.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2024-07-11btrfs: output the unrecognized super block flags as hexQu Wenruo
Most of the extra super block flags are beyond 32bits (from CHANGING_FSID_V2 to CHANGING_*_CSUMS), thus using %llu is not only too long and pretty hard to read. Reviewed-by: Josef Bacik <josef@toxicpanda.com> Signed-off-by: Qu Wenruo <wqu@suse.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2024-07-11btrfs: fix typo in error message in btrfs_validate_super()Mark Harmstone
There's a typo in an error message when checking the block group tree feature, it mentions fres-space-tree instead of free-space-tree. Fix that. Signed-off-by: Mark Harmstone <maharmstone@fb.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2024-07-11btrfs: remove all extra btrfs_check_eb_owner() callsJosef Bacik
Currently we have a handful of btrfs_check_eb_owner() calls in various places and helpers that read extent buffers. However we call this in the endio handler for every metadata block, so these extra checks are unnecessary, simply remove them from everywhere except the endio handler. Reviewed-by: Qu Wenruo <wqu@suse.com> Signed-off-by: Josef Bacik <josef@toxicpanda.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2024-07-11btrfs: constify pointer parameters where applicableDavid Sterba
We can add const to many parameters, this is for clarity and minor addition to safety. There are some minor effects, in the assembly code and .ko measured on release config. This patch does not cover all possible conversions. Signed-off-by: David Sterba <dsterba@suse.com>
2024-07-11btrfs: rename err to ret in btrfs_cleanup_fs_roots()Anand Jain
Since err represents the function return value, rename it as ret, and rename the original ret, which serves as a helper return value, to found. Also, optimize the code to continue call btrfs_put_root() for the rest of the root if even after btrfs_orphan_cleanup() returns error. Signed-off-by: Anand Jain <anand.jain@oracle.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2024-07-11btrfs: add and use helper to commit the current transactionFilipe Manana
We have several places that attach to the current transaction with btrfs_attach_transaction_barrier() and then commit the transaction if there is one. Add a helper and use it to deduplicate this pattern. Reviewed-by: Josef Bacik <josef@toxicpanda.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>
2024-07-11btrfs: avoid create and commit empty transaction when committing superFilipe Manana
At btrfs_commit_super(), called in a few contexts such as when unmounting a filesystem, we use btrfs_join_transaction() to catch any running transaction and then commit it. This will however create a new and empty transaction in case there's no running transaction or there's a running transaction with a state >= TRANS_STATE_UNBLOCKED. As we just want to be sure that any existing transaction is fully committed, we can use btrfs_attach_transaction_barrier() instead of btrfs_join_transaction(), therefore avoiding the creation and commit of empty transactions, which only waste IO and causes rotation of the precious backup roots. Example where we create and commit a pointless empty transaction: $ mkfs.btrfs -f /dev/sdj $ btrfs inspect-internal dump-super /dev/sdj | grep -e '^generation' generation 6 $ mount /dev/sdj /mnt/sdj $ touch /mnt/sdj/foo # Commit the currently open transaction. Just 'sync' or wait ~30 # seconds for the transaction kthread to commit it. $ sync $ btrfs inspect-internal dump-super /dev/sdj | grep -e '^generation' generation 7 $ umount /mnt/sdj $ btrfs inspect-internal dump-super /dev/sdj | grep -e '^generation' generation 8 The transaction with id 8 was pointless, an empty transaction that did not achieve anything. Reviewed-by: Josef Bacik <josef@toxicpanda.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>
2024-07-11btrfs: simplify range parameters of btrfs_wait_ordered_roots()David Sterba
The range is specified only in two ways, we can simplify the case for the whole filesystem range as a NULL block group parameter. Signed-off-by: David Sterba <dsterba@suse.com>
2024-07-11btrfs: move btrfs_block_group_root() to block-group.cAnand Jain
The function btrfs_block_group_root() is declared in disk-io.c; however, all its callers are in block-group.c. Move it to the latter file and declare it static. Reviewed-by: Naohiro Aota <naohiro.aota@wdc.com> Reviewed-by: Qu Wenruo <wqu@suse.com> Signed-off-by: Anand Jain <anand.jain@oracle.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2024-07-11btrfs: remove objectid from struct btrfs_inode on 64 bits platformsFilipe Manana
On 64 bits platforms we don't really need to have a dedicated member (the objectid field) for the inode's number since we store in the VFS inode's i_ino member, which is an unsigned long and this type is 64 bits wide on 64 bits platforms. We only need that field in case we are on a 32 bits platform because the unsigned long type is 32 bits wide on such platforms See commit 33345d01522f ("Btrfs: Always use 64bit inode number") regarding this 64/32 bits detail. The objectid field of struct btrfs_inode is also used to store the ID of a root for directories that are stubs for unreferenced roots. In such cases the inode is a directory and has the BTRFS_INODE_ROOT_STUB runtime flag set. So in order to reduce the size of btrfs_inode structure on 64 bits platforms we can remove the objectid member and use the VFS inode's i_ino member instead whenever we need to get the inode number. In case the inode is a root stub (BTRFS_INODE_ROOT_STUB set) we can use the member last_reflink_trans to store the ID of the unreferenced root, since such inode is a directory and reflinks can't be done against directories. So remove the objectid fields for 64 bits platforms and alias the last_reflink_trans field with a name of ref_root_id in a union. On a release kernel config, this reduces the size of struct btrfs_inode from 1040 bytes down to 1032 bytes. Signed-off-by: Filipe Manana <fdmanana@suse.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2024-07-11btrfs: remove location key from struct btrfs_inodeFilipe Manana
Currently struct btrfs_inode has a key member, named "location", that is either: 1) The key of the inode's item. In this case the objectid is the number of the inode; 2) A key stored in a dir entry with a type of BTRFS_ROOT_ITEM_KEY, for the case where we have a root that is a snapshot of a subvolume that points to other subvolumes. In this case the objectid is the ID of a subvolume inside the snapshotted parent subvolume. The key is only used to lookup the inode item for the first case, while for the second it's never used since it corresponds to directory stubs created with new_simple_dir() and which are marked as dummy, so there's no actual inode item to ever update. In the second case we only check the key type at btrfs_ino() for 32 bits platforms and its objectid is only needed for unlink. Instead of using a key we can do fine with just the objectid, since we can generate the key whenever we need it having only the objectid, as in all use cases the type is always BTRFS_INODE_ITEM_KEY and the offset is always 0. So use only an objectid instead of a full key. This reduces the size of struct btrfs_inode from 1048 bytes down to 1040 bytes on a release kernel. Signed-off-by: Filipe Manana <fdmanana@suse.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2024-07-11btrfs: remove inode_lock from struct btrfs_root and use xarray locksFilipe Manana
Currently we use the spinlock inode_lock from struct btrfs_root to serialize access to two different data structures: 1) The delayed inodes xarray (struct btrfs_root::delayed_nodes); 2) The inodes xarray (struct btrfs_root::inodes). Instead of using our own lock, we can use the spinlock that is part of the xarray implementation, by using the xa_lock() and xa_unlock() APIs and using the xarray APIs with the double underscore prefix that don't take the xarray locks and assume the caller is using xa_lock() and xa_unlock(). So remove the spinlock inode_lock from struct btrfs_root and use the corresponding xarray locks. This brings 2 benefits: 1) We reduce the size of struct btrfs_root, from 1336 bytes down to 1328 bytes on a 64 bits release kernel config; 2) We reduce lock contention by not using anymore the same lock for changing two different and unrelated xarrays. 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>
2024-07-11btrfs: use an xarray to track open inodes in a rootFilipe Manana
Currently we use a red black tree (rb-tree) to track the currently open inodes of a root (in struct btrfs_root::inode_tree). This however is not very efficient when the number of inodes is large since rb-trees are binary trees. For example for 100K open inodes, the tree has a depth of 17. Besides that, inserting into the tree requires navigating through it and pulling useless cache lines in the process since the red black tree nodes are embedded within the btrfs inode - on the other hand, by being embedded, it requires no extra memory allocations. We can improve this by using an xarray instead, which is efficient when indices are densely clustered (such as inode numbers), is more cache friendly and behaves like a resizable array, with a much better search and insertion complexity than a red black tree. This only has one small disadvantage which is that insertion will sometimes require allocating memory for the xarray - which may fail (not that often since it uses a kmem_cache) - but on the other hand we can reduce the btrfs inode structure size by 24 bytes (from 1080 down to 1056 bytes) after removing the embedded red black tree node, which after the next patches will allow to reduce the size of the structure to 1024 bytes, meaning we will be able to store 4 inodes per 4K page instead of 3 inodes. This change does a straightforward change to use an xarray, and results in a transaction abort if we can't allocate memory for the xarray when creating an inode - but the next patch changes things so that we don't need to abort. Running the following fs_mark test showed some improvements: $ cat test.sh #!/bin/bash DEV=/dev/nullb0 MNT=/mnt/nullb0 MOUNT_OPTIONS="-o ssd" FILES=100000 THREADS=$(nproc --all) echo "performance" | \ tee /sys/devices/system/cpu/cpu*/cpufreq/scaling_governor mkfs.btrfs -f $DEV mount $MOUNT_OPTIONS $DEV $MNT OPTS="-S 0 -L 5 -n $FILES -s 0 -t $THREADS -k" for ((i = 1; i <= $THREADS; i++)); do OPTS="$OPTS -d $MNT/d$i" done fs_mark $OPTS umount $MNT Before this patch: FSUse% Count Size Files/sec App Overhead 10 1200000 0 92081.6 12505547 16 2400000 0 138222.6 13067072 23 3600000 0 148833.1 13290336 43 4800000 0 97864.7 13931248 53 6000000 0 85597.3 14384313 After this patch: FSUse% Count Size Files/sec App Overhead 10 1200000 0 93225.1 12571078 16 2400000 0 146720.3 12805007 23 3600000 0 160626.4 13073835 46 4800000 0 116286.2 13802927 53 6000000 0 90087.9 14754892 The test was run with a release kernel config (Debian's default config). Also capturing the insertion times into the rb tree and into the xarray, that is measuring the duration of the old function inode_tree_add() and the duration of the new btrfs_add_inode_to_root() function, gave the following results (in nanoseconds): Before this patch, inode_tree_add() execution times: Count: 5000000 Range: 0.000 - 5536887.000; Mean: 775.674; Median: 729.000; Stddev: 4820.961 Percentiles: 90th: 1015.000; 95th: 1139.000; 99th: 1397.000 0.000 - 7.816: 40 | 7.816 - 37.858: 209 | 37.858 - 170.278: 6059 | 170.278 - 753.961: 2754890 ##################################################### 753.961 - 3326.728: 2232312 ########################################### 3326.728 - 14667.018: 4366 | 14667.018 - 64652.943: 852 | 64652.943 - 284981.761: 550 | 284981.761 - 1256150.914: 221 | 1256150.914 - 5536887.000: 7 | After this patch, btrfs_add_inode_to_root() execution times: Count: 5000000 Range: 0.000 - 2900652.000; Mean: 272.148; Median: 241.000; Stddev: 2873.369 Percentiles: 90th: 342.000; 95th: 432.000; 99th: 572.000 0.000 - 7.264: 104 | 7.264 - 33.145: 352 | 33.145 - 140.081: 109606 # 140.081 - 581.930: 4840090 ##################################################### 581.930 - 2407.590: 43532 | 2407.590 - 9950.979: 2245 | 9950.979 - 41119.278: 514 | 41119.278 - 169902.616: 155 | 169902.616 - 702018.539: 47 | 702018.539 - 2900652.000: 9 | Average, percentiles, standard deviation, etc, are all much better. 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>
2024-06-07Merge tag 'for-6.10-rc2-tag' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux Pull btrfs fixes from David Sterba: - fix handling of folio private changes. The private value holds pointer to our extent buffer structure representing a metadata range. Release and create of the range was not properly synchronized when updating the private bit which ended up in double folio_put, leading to all sorts of breakage - fix a crash, reported as duplicate key in metadata, but caused by a race of fsync and size extending write. Requires prealloc target range + fsync and other conditions (log tree state, timing) - fix leak of qgroup extent records after transaction abort * tag 'for-6.10-rc2-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux: btrfs: protect folio::private when attaching extent buffer folios btrfs: fix leak of qgroup extent records after transaction abort btrfs: fix crash on racing fsync and size-extending write into prealloc
2024-06-05btrfs: fix leak of qgroup extent records after transaction abortFilipe Manana
Qgroup extent records are created when delayed ref heads are created and then released after accounting extents at btrfs_qgroup_account_extents(), called during the transaction commit path. If a transaction is aborted we free the qgroup records by calling btrfs_qgroup_destroy_extent_records() at btrfs_destroy_delayed_refs(), unless we don't have delayed references. We are incorrectly assuming that no delayed references means we don't have qgroup extents records. We can currently have no delayed references because we ran them all during a transaction commit and the transaction was aborted after that due to some error in the commit path. So fix this by ensuring we btrfs_qgroup_destroy_extent_records() at btrfs_destroy_delayed_refs() even if we don't have any delayed references. Reported-by: syzbot+0fecc032fa134afd49df@syzkaller.appspotmail.com Link: https://lore.kernel.org/linux-btrfs/0000000000004e7f980619f91835@google.com/ Fixes: 81f7eb00ff5b ("btrfs: destroy qgroup extent records on transaction abort") CC: stable@vger.kernel.org # 6.1+ Reviewed-by: Josef Bacik <josef@toxicpanda.com> Reviewed-by: Qu Wenruo <wqu@suse.com> Signed-off-by: Filipe Manana <fdmanana@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2024-05-21Merge tag 'pull-bd_inode-1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs Pull bdev bd_inode updates from Al Viro: "Replacement of bdev->bd_inode with sane(r) set of primitives by me and Yu Kuai" * tag 'pull-bd_inode-1' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: RIP ->bd_inode dasd_format(): killing the last remaining user of ->bd_inode nilfs_attach_log_writer(): use ->bd_mapping->host instead of ->bd_inode block/bdev.c: use the knowledge of inode/bdev coallocation gfs2: more obvious initializations of mapping->host fs/buffer.c: massage the remaining users of ->bd_inode to ->bd_mapping blk_ioctl_{discard,zeroout}(): we only want ->bd_inode->i_mapping here... grow_dev_folio(): we only want ->bd_inode->i_mapping there use ->bd_mapping instead of ->bd_inode->i_mapping block_device: add a pointer to struct address_space (page cache of bdev) missing helpers: bdev_unhash(), bdev_drop() block: move two helpers into bdev.c block2mtd: prevent direct access of bd_inode dm-vdo: use bdev_nr_bytes(bdev) instead of i_size_read(bdev->bd_inode) blkdev_write_iter(): saner way to get inode and bdev bcachefs: remove dead function bdev_sectors() ext4: remove block_device_ejected() erofs_buf: store address_space instead of inode erofs: switch erofs_bread() to passing offset instead of block number
2024-05-07btrfs: count super block write errors in device instead of tracking folio ↵Matthew Wilcox (Oracle)
error state Currently the error status of super block write is tracked in page/folio status bit Error. For that we need to keep the reference for the whole duration of write and wait. Count the number of superblock writeback errors in the btrfs_device. That means we don't need the folio to stay around until it's waited for, and can avoid the extra call to folio_get/put. Also remove a mention of PageError in a comment as it's the last mention of the page Error state. Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2024-05-07btrfs: use the folio iterator in btrfs_end_super_write()Matthew Wilcox (Oracle)
Iterate over folios instead of bvecs. Switch the order of unlock and put to be the usual order; we know this folio can't be put until it's been waited for, but that's fragile. Remove the calls to ClearPageUptodate / SetPageUptodate -- if PAGE_SIZE is larger than BTRFS_SUPER_INFO_SIZE, we'd be marking the entire folio uptodate without having actually initialised all the bytes in the page. Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2024-05-07btrfs: convert super block writes to folio in write_dev_supers()Matthew Wilcox (Oracle)
This is a direct conversion from pages to folios, assuming single page folio. Also removes some calls to obsolete APIs and some hidden calls to compound_head(). Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2024-05-07btrfs: convert super block writes to folio in wait_dev_supers()Matthew Wilcox (Oracle)
This is a direct conversion from pages to folios, assuming single page folio. Also removes a few calls to compound_head() and calls to obsolete APIs. Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2024-05-07btrfs: use btrfs_is_testing() everywhereDavid Sterba
There are open coded tests of BTRFS_FS_STATE_DUMMY_FS_INFO and we have a wrapper for that that's a compile-time constant when self-tests are not built in. As this is only for development we can save some bytes and conditions on release configs by using the helper in the remaining cases. Reviewed-by: Josef Bacik <josef@toxicpanda.com> Signed-off-by: David Sterba <dsterba@suse.com>
2024-05-07btrfs: initialize delayed inodes xarray without GFP_ATOMICFilipe Manana
There's no need to initialize the delayed inodes xarray with a GFP_ATOMIC flag because that actually does nothing on the xarray operations. That was needed for radix trees, but for xarrays the allocation flags are passed as the last argument to xa_store() (which we are using correctly). So initialize the delayed inodes xarray with a simple xa_init(). Reviewed-by: Josef Bacik <josef@toxicpanda.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>
2024-05-07btrfs: add a global per cpu counter to track number of used extent mapsFilipe Manana
Add a per cpu counter that tracks the total number of extent maps that are in extent trees of inodes that belong to fs trees. This is going to be used in an upcoming change that adds a shrinker for extent maps. Only extent maps for fs trees are considered, because for special trees such as the data relocation tree we don't want to evict their extent maps which are critical for the relocation to work, and since those are limited, it's not a concern to have them in memory during the relocation of a block group. Another case are extent maps for free space cache inodes, which must always remain in memory, but those are limited (there's only one per free space cache inode, which means one per block group). Reviewed-by: Josef Bacik <josef@toxicpanda.com> Signed-off-by: Filipe Manana <fdmanana@suse.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2024-05-07btrfs: change root->root_key.objectid to btrfs_root_id()Josef Bacik
A comment from Filipe on one of my previous cleanups brought my attention to a new helper we have for getting the root id of a root, which makes it easier to read in the code. The changes where made with the following Coccinelle semantic patch: // <smpl> @@ expression E,E1; @@ ( E->root_key.objectid = E1 | - E->root_key.objectid + btrfs_root_id(E) ) // </smpl> Reviewed-by: Filipe Manana <fdmanana@suse.com> Signed-off-by: Josef Bacik <josef@toxicpanda.com> Reviewed-by: David Sterba <dsterba@suse.com> [ minor style fixups ] Signed-off-by: David Sterba <dsterba@suse.com>
2024-05-07btrfs: remove list_empty() check at warn_about_uncommitted_trans()Filipe Manana
At warn_about_uncommitted_trans(), there's no need to check if the list is empty and return, because list_for_each_entry_safe() is safe to call for an empty list, it simply does nothing. So remove the check. 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>
2024-05-07btrfs: free PERTRANS at the end of cleanup_transaction()Boris Burkov
Some of the operations after the free might convert more PERTRANS metadata. Do the freeing as late as possible to eliminate a source of leaked PERTRANS metadata. This helps with the pass rate of generic/269 and generic/475. Reviewed-by: Qu Wenruo <qwu@suse.com> Signed-off-by: Boris Burkov <boris@bur.io> Signed-off-by: David Sterba <dsterba@suse.com>
2024-05-03use ->bd_mapping instead of ->bd_inode->i_mappingAl Viro
Just the low-hanging fruit... Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Link: https://lore.kernel.org/r/20240411145346.2516848-2-viro@zeniv.linux.org.uk Signed-off-by: Christian Brauner <brauner@kernel.org>