- 22 Oct, 2018 1 commit
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Filipe Manana authored
We were iterating a block group's free space cache rbtree without locking first the lock that protects it (the free_space_ctl->free_space_offset rbtree is protected by the free_space_ctl->tree_lock spinlock). KASAN reported an use-after-free problem when iterating such a rbtree due to a concurrent rbtree delete: [ 9520.359168] ================================================================== [ 9520.359656] BUG: KASAN: use-after-free in rb_next+0x13/0x90 [ 9520.359949] Read of size 8 at addr ffff8800b7ada500 by task btrfs-transacti/1721 [ 9520.360357] [ 9520.360530] CPU: 4 PID: 1721 Comm: btrfs-transacti Tainted: G L 4.19.0-rc8-nbor #555 [ 9520.360990] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.10.2-1ubuntu1 04/01/2014 [ 9520.362682] Call Trace: [ 9520.362887] dump_stack+0xa4/0xf5 [ 9520.363146] print_address_description+0x78/0x280 [ 9520.363412] kasan_report+0x263/0x390 [ 9520.363650] ? rb_next+0x13/0x90 [ 9520.363873] __asan_load8+0x54/0x90 [ 9520.364102] rb_next+0x13/0x90 [ 9520.364380] btrfs_dump_free_space+0x146/0x160 [btrfs] [ 9520.364697] dump_space_info+0x2cd/0x310 [btrfs] [ 9520.364997] btrfs_reserve_extent+0x1ee/0x1f0 [btrfs] [ 9520.365310] __btrfs_prealloc_file_range+0x1cc/0x620 [btrfs] [ 9520.365646] ? btrfs_update_time+0x180/0x180 [btrfs] [ 9520.365923] ? _raw_spin_unlock+0x27/0x40 [ 9520.366204] ? btrfs_alloc_data_chunk_ondemand+0x2c0/0x5c0 [btrfs] [ 9520.366549] btrfs_prealloc_file_range_trans+0x23/0x30 [btrfs] [ 9520.366880] cache_save_setup+0x42e/0x580 [btrfs] [ 9520.367220] ? btrfs_check_data_free_space+0xd0/0xd0 [btrfs] [ 9520.367518] ? lock_downgrade+0x2f0/0x2f0 [ 9520.367799] ? btrfs_write_dirty_block_groups+0x11f/0x6e0 [btrfs] [ 9520.368104] ? kasan_check_read+0x11/0x20 [ 9520.368349] ? do_raw_spin_unlock+0xa8/0x140 [ 9520.368638] btrfs_write_dirty_block_groups+0x2af/0x6e0 [btrfs] [ 9520.368978] ? btrfs_start_dirty_block_groups+0x870/0x870 [btrfs] [ 9520.369282] ? do_raw_spin_unlock+0xa8/0x140 [ 9520.369534] ? _raw_spin_unlock+0x27/0x40 [ 9520.369811] ? btrfs_run_delayed_refs+0x1b8/0x230 [btrfs] [ 9520.370137] commit_cowonly_roots+0x4b9/0x610 [btrfs] [ 9520.370560] ? commit_fs_roots+0x350/0x350 [btrfs] [ 9520.370926] ? btrfs_run_delayed_refs+0x1b8/0x230 [btrfs] [ 9520.371285] btrfs_commit_transaction+0x5e5/0x10e0 [btrfs] [ 9520.371612] ? btrfs_apply_pending_changes+0x90/0x90 [btrfs] [ 9520.371943] ? start_transaction+0x168/0x6c0 [btrfs] [ 9520.372257] transaction_kthread+0x21c/0x240 [btrfs] [ 9520.372537] kthread+0x1d2/0x1f0 [ 9520.372793] ? btrfs_cleanup_transaction+0xb50/0xb50 [btrfs] [ 9520.373090] ? kthread_park+0xb0/0xb0 [ 9520.373329] ret_from_fork+0x3a/0x50 [ 9520.373567] [ 9520.373738] Allocated by task 1804: [ 9520.373974] kasan_kmalloc+0xff/0x180 [ 9520.374208] kasan_slab_alloc+0x11/0x20 [ 9520.374447] kmem_cache_alloc+0xfc/0x2d0 [ 9520.374731] __btrfs_add_free_space+0x40/0x580 [btrfs] [ 9520.375044] unpin_extent_range+0x4f7/0x7a0 [btrfs] [ 9520.375383] btrfs_finish_extent_commit+0x15f/0x4d0 [btrfs] [ 9520.375707] btrfs_commit_transaction+0xb06/0x10e0 [btrfs] [ 9520.376027] btrfs_alloc_data_chunk_ondemand+0x237/0x5c0 [btrfs] [ 9520.376365] btrfs_check_data_free_space+0x81/0xd0 [btrfs] [ 9520.376689] btrfs_delalloc_reserve_space+0x25/0x80 [btrfs] [ 9520.377018] btrfs_direct_IO+0x42e/0x6d0 [btrfs] [ 9520.377284] generic_file_direct_write+0x11e/0x220 [ 9520.377587] btrfs_file_write_iter+0x472/0xac0 [btrfs] [ 9520.377875] aio_write+0x25c/0x360 [ 9520.378106] io_submit_one+0xaa0/0xdc0 [ 9520.378343] __se_sys_io_submit+0xfa/0x2f0 [ 9520.378589] __x64_sys_io_submit+0x43/0x50 [ 9520.378840] do_syscall_64+0x7d/0x240 [ 9520.379081] entry_SYSCALL_64_after_hwframe+0x49/0xbe [ 9520.379387] [ 9520.379557] Freed by task 1802: [ 9520.379782] __kasan_slab_free+0x173/0x260 [ 9520.380028] kasan_slab_free+0xe/0x10 [ 9520.380262] kmem_cache_free+0xc1/0x2c0 [ 9520.380544] btrfs_find_space_for_alloc+0x4cd/0x4e0 [btrfs] [ 9520.380866] find_free_extent+0xa99/0x17e0 [btrfs] [ 9520.381166] btrfs_reserve_extent+0xd5/0x1f0 [btrfs] [ 9520.381474] btrfs_get_blocks_direct+0x60b/0xbd0 [btrfs] [ 9520.381761] __blockdev_direct_IO+0x10ee/0x58a1 [ 9520.382059] btrfs_direct_IO+0x25a/0x6d0 [btrfs] [ 9520.382321] generic_file_direct_write+0x11e/0x220 [ 9520.382623] btrfs_file_write_iter+0x472/0xac0 [btrfs] [ 9520.382904] aio_write+0x25c/0x360 [ 9520.383172] io_submit_one+0xaa0/0xdc0 [ 9520.383416] __se_sys_io_submit+0xfa/0x2f0 [ 9520.383678] __x64_sys_io_submit+0x43/0x50 [ 9520.383927] do_syscall_64+0x7d/0x240 [ 9520.384165] entry_SYSCALL_64_after_hwframe+0x49/0xbe [ 9520.384439] [ 9520.384610] The buggy address belongs to the object at ffff8800b7ada500 which belongs to the cache btrfs_free_space of size 72 [ 9520.385175] The buggy address is located 0 bytes inside of 72-byte region [ffff8800b7ada500, ffff8800b7ada548) [ 9520.385691] The buggy address belongs to the page: [ 9520.385957] page:ffffea0002deb680 count:1 mapcount:0 mapping:ffff880108a1d700 index:0x0 compound_mapcount: 0 [ 9520.388030] flags: 0x8100(slab|head) [ 9520.388281] raw: 0000000000008100 ffffea0002deb608 ffffea0002728808 ffff880108a1d700 [ 9520.388722] raw: 0000000000000000 0000000000130013 00000001ffffffff 0000000000000000 [ 9520.389169] page dumped because: kasan: bad access detected [ 9520.389473] [ 9520.389658] Memory state around the buggy address: [ 9520.389943] ffff8800b7ada400: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc [ 9520.390368] ffff8800b7ada480: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc [ 9520.390796] >ffff8800b7ada500: fb fb fb fb fb fb fb fb fb fc fc fc fc fc fc fc [ 9520.391223] ^ [ 9520.391461] ffff8800b7ada580: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc [ 9520.391885] ffff8800b7ada600: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc [ 9520.392313] ================================================================== [ 9520.392772] BTRFS critical (device vdc): entry offset 2258497536, bytes 131072, bitmap no [ 9520.393247] BUG: unable to handle kernel NULL pointer dereference at 0000000000000011 [ 9520.393705] PGD 800000010dbab067 P4D 800000010dbab067 PUD 107551067 PMD 0 [ 9520.394059] Oops: 0000 [#1] SMP DEBUG_PAGEALLOC KASAN PTI [ 9520.394378] CPU: 4 PID: 1721 Comm: btrfs-transacti Tainted: G B L 4.19.0-rc8-nbor #555 [ 9520.394858] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.10.2-1ubuntu1 04/01/2014 [ 9520.395350] RIP: 0010:rb_next+0x3c/0x90 [ 9520.396461] RSP: 0018:ffff8801074ff780 EFLAGS: 00010292 [ 9520.396762] RAX: 0000000000000000 RBX: 0000000000000001 RCX: ffffffff81b5ac4c [ 9520.397115] RDX: 0000000000000000 RSI: 0000000000000008 RDI: 0000000000000011 [ 9520.397468] RBP: ffff8801074ff7a0 R08: ffffed0021d64ccc R09: ffffed0021d64ccc [ 9520.397821] R10: 0000000000000001 R11: ffffed0021d64ccb R12: ffff8800b91e0000 [ 9520.398188] R13: ffff8800a3ceba48 R14: ffff8800b627bf80 R15: 0000000000020000 [ 9520.398555] FS: 0000000000000000(0000) GS:ffff88010eb00000(0000) knlGS:0000000000000000 [ 9520.399007] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 9520.399335] CR2: 0000000000000011 CR3: 0000000106b52000 CR4: 00000000000006a0 [ 9520.399679] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 [ 9520.400023] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 [ 9520.400400] Call Trace: [ 9520.400648] btrfs_dump_free_space+0x146/0x160 [btrfs] [ 9520.400974] dump_space_info+0x2cd/0x310 [btrfs] [ 9520.401287] btrfs_reserve_extent+0x1ee/0x1f0 [btrfs] [ 9520.401609] __btrfs_prealloc_file_range+0x1cc/0x620 [btrfs] [ 9520.401952] ? btrfs_update_time+0x180/0x180 [btrfs] [ 9520.402232] ? _raw_spin_unlock+0x27/0x40 [ 9520.402522] ? btrfs_alloc_data_chunk_ondemand+0x2c0/0x5c0 [btrfs] [ 9520.402882] btrfs_prealloc_file_range_trans+0x23/0x30 [btrfs] [ 9520.403261] cache_save_setup+0x42e/0x580 [btrfs] [ 9520.403570] ? btrfs_check_data_free_space+0xd0/0xd0 [btrfs] [ 9520.403871] ? lock_downgrade+0x2f0/0x2f0 [ 9520.404161] ? btrfs_write_dirty_block_groups+0x11f/0x6e0 [btrfs] [ 9520.404481] ? kasan_check_read+0x11/0x20 [ 9520.404732] ? do_raw_spin_unlock+0xa8/0x140 [ 9520.405026] btrfs_write_dirty_block_groups+0x2af/0x6e0 [btrfs] [ 9520.405375] ? btrfs_start_dirty_block_groups+0x870/0x870 [btrfs] [ 9520.405694] ? do_raw_spin_unlock+0xa8/0x140 [ 9520.405958] ? _raw_spin_unlock+0x27/0x40 [ 9520.406243] ? btrfs_run_delayed_refs+0x1b8/0x230 [btrfs] [ 9520.406574] commit_cowonly_roots+0x4b9/0x610 [btrfs] [ 9520.406899] ? commit_fs_roots+0x350/0x350 [btrfs] [ 9520.407253] ? btrfs_run_delayed_refs+0x1b8/0x230 [btrfs] [ 9520.407589] btrfs_commit_transaction+0x5e5/0x10e0 [btrfs] [ 9520.407925] ? btrfs_apply_pending_changes+0x90/0x90 [btrfs] [ 9520.408262] ? start_transaction+0x168/0x6c0 [btrfs] [ 9520.408582] transaction_kthread+0x21c/0x240 [btrfs] [ 9520.408870] kthread+0x1d2/0x1f0 [ 9520.409138] ? btrfs_cleanup_transaction+0xb50/0xb50 [btrfs] [ 9520.409440] ? kthread_park+0xb0/0xb0 [ 9520.409682] ret_from_fork+0x3a/0x50 [ 9520.410508] Dumping ftrace buffer: [ 9520.410764] (ftrace buffer empty) [ 9520.411007] CR2: 0000000000000011 [ 9520.411297] ---[ end trace 01a0863445cf360a ]--- [ 9520.411568] RIP: 0010:rb_next+0x3c/0x90 [ 9520.412644] RSP: 0018:ffff8801074ff780 EFLAGS: 00010292 [ 9520.412932] RAX: 0000000000000000 RBX: 0000000000000001 RCX: ffffffff81b5ac4c [ 9520.413274] RDX: 0000000000000000 RSI: 0000000000000008 RDI: 0000000000000011 [ 9520.413616] RBP: ffff8801074ff7a0 R08: ffffed0021d64ccc R09: ffffed0021d64ccc [ 9520.414007] R10: 0000000000000001 R11: ffffed0021d64ccb R12: ffff8800b91e0000 [ 9520.414349] R13: ffff8800a3ceba48 R14: ffff8800b627bf80 R15: 0000000000020000 [ 9520.416074] FS: 0000000000000000(0000) GS:ffff88010eb00000(0000) knlGS:0000000000000000 [ 9520.416536] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 9520.416848] CR2: 0000000000000011 CR3: 0000000106b52000 CR4: 00000000000006a0 [ 9520.418477] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 [ 9520.418846] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 [ 9520.419204] Kernel panic - not syncing: Fatal exception [ 9520.419666] Dumping ftrace buffer: [ 9520.419930] (ftrace buffer empty) [ 9520.420168] Kernel Offset: disabled [ 9520.420406] ---[ end Kernel panic - not syncing: Fatal exception ]--- Fix this by acquiring the respective lock before iterating the rbtree. Reported-by:Nikolay Borisov <nborisov@suse.com> CC: stable@vger.kernel.org # 4.4+ Reviewed-by:
Josef Bacik <josef@toxicpanda.com> Signed-off-by:
Filipe Manana <fdmanana@suse.com> Signed-off-by:
David Sterba <dsterba@suse.com>
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- 19 Oct, 2018 9 commits
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Filipe Manana authored
At inode.c:evict_inode_truncate_pages(), when we iterate over the inode's extent states, we access an extent state record's "state" field after we unlocked the inode's io tree lock. This can lead to a use-after-free issue because after we unlock the io tree that extent state record might have been freed due to being merged into another adjacent extent state record (a previous inflight bio for a read operation finished in the meanwhile which unlocked a range in the io tree and cause a merge of extent state records, as explained in the comment before the while loop added in commit 6ca07097 ("Btrfs: fix hang during inode eviction due to concurrent readahead")). Fix this by keeping a copy of the extent state's flags in a local variable and using it after unlocking the io tree. Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=201189 Fixes: b9d0b389 ("btrfs: Add handler for invalidate page") CC: stable@vger.kernel.org # 4.4+ Reviewed-by:
Qu Wenruo <wqu@suse.com> Signed-off-by:
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Josef Bacik authored
We're getting a lockdep splat because we take the dio_sem under the log_mutex. What we really need is to protect fsync() from logging an extent map for an extent we never waited on higher up, so just guard the whole thing with dio_sem. ====================================================== WARNING: possible circular locking dependency detected 4.18.0-rc4-xfstests-00025-g5de5edbaf1d4 #411 Not tainted ------------------------------------------------------ aio-dio-invalid/30928 is trying to acquire lock: 0000000092621cfd (&mm->mmap_sem){++++}, at: get_user_pages_unlocked+0x5a/0x1e0 but task is already holding lock: 00000000cefe6b35 (&ei->dio_sem){++++}, at: btrfs_direct_IO+0x3be/0x400 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #5 (&ei->dio_sem){++++}: lock_acquire+0xbd/0x220 down_write+0x51/0xb0 btrfs_log_changed_extents+0x80/0xa40 btrfs_log_inode+0xbaf/0x1000 btrfs_log_inode_parent+0x26f/0xa80 btrfs_log_dentry_safe+0x50/0x70 btrfs_sync_file+0x357/0x540 do_fsync+0x38/0x60 __ia32_sys_fdatasync+0x12/0x20 do_fast_syscall_32+0x9a/0x2f0 entry_SYSENTER_compat+0x84/0x96 -> #4 (&ei->log_mutex){+.+.}: lock_acquire+0xbd/0x220 __mutex_lock+0x86/0xa10 btrfs_record_unlink_dir+0x2a/0xa0 btrfs_unlink+0x5a/0xc0 vfs_unlink+0xb1/0x1a0 do_unlinkat+0x264/0x2b0 do_fast_syscall_32+0x9a/0x2f0 entry_SYSENTER_compat+0x84/0x96 -> #3 (sb_internal#2){.+.+}: lock_acquire+0xbd/0x220 __sb_start_write+0x14d/0x230 start_transaction+0x3e6/0x590 btrfs_evict_inode+0x475/0x640 evict+0xbf/0x1b0 btrfs_run_delayed_iputs+0x6c/0x90 cleaner_kthread+0x124/0x1a0 kthread+0x106/0x140 ret_from_fork+0x3a/0x50 -> #2 (&fs_info->cleaner_delayed_iput_mutex){+.+.}: lock_acquire+0xbd/0x220 __mutex_lock+0x86/0xa10 btrfs_alloc_data_chunk_ondemand+0x197/0x530 btrfs_check_data_free_space+0x4c/0x90 btrfs_delalloc_reserve_space+0x20/0x60 btrfs_page_mkwrite+0x87/0x520 do_page_mkwrite+0x31/0xa0 __handle_mm_fault+0x799/0xb00 handle_mm_fault+0x7c/0xe0 __do_page_fault+0x1d3/0x4a0 async_page_fault+0x1e/0x30 -> #1 (sb_pagefaults){.+.+}: lock_acquire+0xbd/0x220 __sb_start_write+0x14d/0x230 btrfs_page_mkwrite+0x6a/0x520 do_page_mkwrite+0x31/0xa0 __handle_mm_fault+0x799/0xb00 handle_mm_fault+0x7c/0xe0 __do_page_fault+0x1d3/0x4a0 async_page_fault+0x1e/0x30 -> #0 (&mm->mmap_sem){++++}: __lock_acquire+0x42e/0x7a0 lock_acquire+0xbd/0x220 down_read+0x48/0xb0 get_user_pages_unlocked+0x5a/0x1e0 get_user_pages_fast+0xa4/0x150 iov_iter_get_pages+0xc3/0x340 do_direct_IO+0xf93/0x1d70 __blockdev_direct_IO+0x32d/0x1c20 btrfs_direct_IO+0x227/0x400 generic_file_direct_write+0xcf/0x180 btrfs_file_write_iter+0x308/0x58c aio_write+0xf8/0x1d0 io_submit_one+0x3a9/0x620 __ia32_compat_sys_io_submit+0xb2/0x270 do_int80_syscall_32+0x5b/0x1a0 entry_INT80_compat+0x88/0xa0 other info that might help us debug this: Chain exists of: &mm->mmap_sem --> &ei->log_mutex --> &ei->dio_sem Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(&ei->dio_sem); lock(&ei->log_mutex); lock(&ei->dio_sem); lock(&mm->mmap_sem); *** DEADLOCK *** 1 lock held by aio-dio-invalid/30928: #0: 00000000cefe6b35 (&ei->dio_sem){++++}, at: btrfs_direct_IO+0x3be/0x400 stack backtrace: CPU: 0 PID: 30928 Comm: aio-dio-invalid Not tainted 4.18.0-rc4-xfstests-00025-g5de5edbaf1d4 #411 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.11.0-2.el7 04/01/2014 Call Trace: dump_stack+0x7c/0xbb print_circular_bug.isra.37+0x297/0x2a4 check_prev_add.constprop.45+0x781/0x7a0 ? __lock_acquire+0x42e/0x7a0 validate_chain.isra.41+0x7f0/0xb00 __lock_acquire+0x42e/0x7a0 lock_acquire+0xbd/0x220 ? get_user_pages_unlocked+0x5a/0x1e0 down_read+0x48/0xb0 ? get_user_pages_unlocked+0x5a/0x1e0 get_user_pages_unlocked+0x5a/0x1e0 get_user_pages_fast+0xa4/0x150 iov_iter_get_pages+0xc3/0x340 do_direct_IO+0xf93/0x1d70 ? __alloc_workqueue_key+0x358/0x490 ? __blockdev_direct_IO+0x14b/0x1c20 __blockdev_direct_IO+0x32d/0x1c20 ? btrfs_run_delalloc_work+0x40/0x40 ? can_nocow_extent+0x490/0x490 ? kvm_clock_read+0x1f/0x30 ? can_nocow_extent+0x490/0x490 ? btrfs_run_delalloc_work+0x40/0x40 btrfs_direct_IO+0x227/0x400 ? btrfs_run_delalloc_work+0x40/0x40 generic_file_direct_write+0xcf/0x180 btrfs_file_write_iter+0x308/0x58c aio_write+0xf8/0x1d0 ? kvm_clock_read+0x1f/0x30 ? __might_fault+0x3e/0x90 io_submit_one+0x3a9/0x620 ? io_submit_one+0xe5/0x620 __ia32_compat_sys_io_submit+0xb2/0x270 do_int80_syscall_32+0x5b/0x1a0 entry_INT80_compat+0x88/0xa0 CC: stable@vger.kernel.org # 4.14+ Reviewed-by: -
Josef Bacik authored
This could result in a really bad case where we do something like evict evict_refill_and_join btrfs_commit_transaction btrfs_run_delayed_iputs evict evict_refill_and_join btrfs_commit_transaction ... forever We have plenty of other places where we run delayed iputs that are much safer, let those do the work. CC: stable@vger.kernel.org # 4.4+ Reviewed-by: -
Josef Bacik authored
We were not handling the reserved byte accounting properly for data references. Metadata was fine, if it errored out the error paths would free the bytes_reserved count and pin the extent, but it even missed one of the error cases. So instead move this handling up into run_one_delayed_ref so we are sure that both cases are properly cleaned up in case of a transaction abort. CC: stable@vger.kernel.org # 4.18+ Reviewed-by:
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Josef Bacik authored
When we insert the file extent once the ordered extent completes we free the reserved extent reservation as it'll have been migrated to the bytes_used counter. However if we error out after this step we'll still clear the reserved extent reservation, resulting in a negative accounting of the reserved bytes for the block group and space info. Fix this by only doing the free if we didn't successfully insert a file extent for this extent. CC: stable@vger.kernel.org # 4.14+ Reviewed-by:
Omar Sandoval <osandov@fb.com> Reviewed-by:
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Josef Bacik authored
max_extent_size is supposed to be the largest contiguous range for the space info, and ctl->free_space is the total free space in the block group. We need to keep track of these separately and _only_ use the max_free_space if we don't have a max_extent_size, as that means our original request was too large to search any of the block groups for and therefore wouldn't have a max_extent_size set. CC: stable@vger.kernel.org # 4.14+ Reviewed-by:
Josef Bacik <jbacik@fb.com> Signed-off-by:
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Josef Bacik authored
We can't use entry->bytes if our entry is a bitmap entry, we need to use entry->max_extent_size in that case. Fix up all the logic to make this consistent. CC: stable@vger.kernel.org # 4.4+ Signed-off-by:
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Josef Bacik authored
If we use up our block group before allocating a new one we'll easily get a max_extent_size that's set really really low, which will result in a lot of fragmentation. We need to make sure we're resetting the max_extent_size when we add a new chunk or add new space. CC: stable@vger.kernel.org # 4.4+ Reviewed-by:
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Josef Bacik authored
My work email is completely useless, switch it to my personal address so I get emails on a account I actually pay attention to. Signed-off-by:
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- 17 Oct, 2018 4 commits
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Lu Fengqi authored
The find_ref_head shouldn't return the first entry even if no exact match is found. So move the hidden behavior to higher level. Besides, remove the useless local variables in the btrfs_select_ref_head. Reviewed-by:
Lu Fengqi <lufq.fnst@cn.fujitsu.com> [ reformat comment ] Signed-off-by:
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Filipe Manana authored
When writing out a block group free space cache we can end deadlocking with ourselves on an extent buffer lock resulting in a warning like the following: [245043.379979] WARNING: CPU: 4 PID: 2608 at fs/btrfs/locking.c:251 btrfs_tree_lock+0x1be/0x1d0 [btrfs] [245043.392792] CPU: 4 PID: 2608 Comm: btrfs-transacti Tainted: G W I 4.16.8 #1 [245043.395489] RIP: 0010:btrfs_tree_lock+0x1be/0x1d0 [btrfs] [245043.396791] RSP: 0018:ffffc9000424b840 EFLAGS: 00010246 [245043.398093] RAX: 0000000000000a30 RBX: ffff8807e20a3d20 RCX: 0000000000000001 [245043.399414] RDX: 0000000000000001 RSI: 0000000000000002 RDI: ffff8807e20a3d20 [245043.400732] RBP: 0000000000000001 R08: ffff88041f39a700 R09: ffff880000000000 [245043.402021] R10: 0000000000000040 R11: ffff8807e20a3d20 R12: ffff8807cb220630 [245043.403296] R13: 0000000000000001 R14: ffff8807cb220628 R15: ffff88041fbdf000 [245043.404780] FS: 0000000000000000(0000) GS:ffff88082fc80000(0000) knlGS:0000000000000000 [245043.406050] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [245043.407321] CR2: 00007fffdbdb9f10 CR3: 0000000001c09005 CR4: 00000000000206e0 [245043.408670] Call Trace: [245043.409977] btrfs_search_slot+0x761/0xa60 [btrfs] [245043.411278] btrfs_insert_empty_items+0x62/0xb0 [btrfs] [245043.412572] btrfs_insert_item+0x5b/0xc0 [btrfs] [245043.413922] btrfs_create_pending_block_groups+0xfb/0x1e0 [btrfs] [245043.415216] do_chunk_alloc+0x1e5/0x2a0 [btrfs] [245043.416487] find_free_extent+0xcd0/0xf60 [btrfs] [245043.417813] btrfs_reserve_extent+0x96/0x1e0 [btrfs] [245043.419105] btrfs_alloc_tree_block+0xfb/0x4a0 [btrfs] [245043.420378] __btrfs_cow_block+0x127/0x550 [btrfs] [245043.421652] btrfs_cow_block+0xee/0x190 [btrfs] [245043.422979] btrfs_search_slot+0x227/0xa60 [btrfs] [245043.424279] ? btrfs_update_inode_item+0x59/0x100 [btrfs] [245043.425538] ? iput+0x72/0x1e0 [245043.426798] write_one_cache_group.isra.49+0x20/0x90 [btrfs] [245043.428131] btrfs_start_dirty_block_groups+0x102/0x420 [btrfs] [245043.429419] btrfs_commit_transaction+0x11b/0x880 [btrfs] [245043.430712] ? start_transaction+0x8e/0x410 [btrfs] [245043.432006] transaction_kthread+0x184/0x1a0 [btrfs] [245043.433341] kthread+0xf0/0x130 [245043.434628] ? btrfs_cleanup_transaction+0x4e0/0x4e0 [btrfs] [245043.435928] ? kthread_create_worker_on_cpu+0x40/0x40 [245043.437236] ret_from_fork+0x1f/0x30 [245043.441054] ---[ end trace 15abaa2aaf36827f ]--- This is because at write_one_cache_group() when we are COWing a leaf from the extent tree we end up allocating a new block group (chunk) and, because we have hit a threshold on the number of bytes reserved for system chunks, we attempt to finalize the creation of new block groups from the current transaction, by calling btrfs_create_pending_block_groups(). However here we also need to modify the extent tree in order to insert a block group item, and if the location for this new block group item happens to be in the same leaf that we were COWing earlier, we deadlock since btrfs_search_slot() tries to write lock the extent buffer that we locked before at write_one_cache_group(). We have already hit similar cases in the past and commit d9a0540a ("Btrfs: fix deadlock when finalizing block group creation") fixed some of those cases by delaying the creation of pending block groups at the known specific spots that could lead to a deadlock. This change reworks that commit to be more generic so that we don't have to add similar logic to every possible path that can lead to a deadlock. This is done by making __btrfs_cow_block() disallowing the creation of new block groups (setting the transaction's can_flush_pending_bgs to false) before it attempts to allocate a new extent buffer for either the extent, chunk or device trees, since those are the trees that pending block creation modifies. Once the new extent buffer is allocated, it allows creation of pending block groups to happen again. This change depends on a recent patch from Josef which is not yet in Linus' tree, named "btrfs: make sure we create all new block groups" in order to avoid occasional warnings at btrfs_trans_release_chunk_metadata(). Fixes: d9a0540a ("Btrfs: fix deadlock when finalizing block group creation") CC: stable@vger.kernel.org # 4.4+ Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=199753 Link: https://lore.kernel.org/linux-btrfs/CAJtFHUTHna09ST-_EEiyWmDH6gAqS6wa=zMNMBsifj8ABu99cw@mail.gmail.com/Reported-by:E V <eliventer@gmail.com> Reviewed-by:
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Filipe Manana authored
When using the NO_HOLES feature and logging a regular file, we were expecting that if we find an inline extent, that either its size in RAM (uncompressed and unenconded) matches the size of the file or if it does not, that it matches the sector size and it represents compressed data. This assertion does not cover a case where the length of the inline extent is smaller than the sector size and also smaller the file's size, such case is possible through fallocate. Example: $ mkfs.btrfs -f -O no-holes /dev/sdb $ mount /dev/sdb /mnt $ xfs_io -f -c "pwrite -S 0xb60 0 21" /mnt/foobar $ xfs_io -c "falloc 40 40" /mnt/foobar $ xfs_io -c "fsync" /mnt/foobar In the above example we trigger the assertion because the inline extent's length is 21 bytes while the file size is 80 bytes. The fallocate() call merely updated the file's size and did not touch the existing inline extent, as expected. So fix this by adjusting the assertion so that an inline extent length smaller than the file size is valid if the file size is smaller than the filesystem's sector size. A test case for fstests follows soon. Reported-by:
Anatoly Trosinenko <anatoly.trosinenko@gmail.com> Fixes: a89ca6f2 ("Btrfs: fix fsync after truncate when no_holes feature is enabled") CC: stable@vger.kernel.org # 4.14+ Link: https://lore.kernel.org/linux-btrfs/CAE5jQCfRSBC7n4pUTFJcmHh109=gwyT9mFkCOL+NKfzswmR=_Q@mail.gmail.com/Signed-off-by:
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Filipe Manana authored
At inode.c:compress_file_range(), under the "free_pages_out" label, we can end up dereferencing the "pages" pointer when it has a NULL value. This case happens when "start" has a value of 0 and we fail to allocate memory for the "pages" pointer. When that happens we jump to the "cont" label and then enter the "if (start == 0)" branch where we immediately call the cow_file_range_inline() function. If that function returns 0 (success creating an inline extent) or an error (like -ENOMEM for example) we jump to the "free_pages_out" label and then access "pages[i]" leading to a NULL pointer dereference, since "nr_pages" has a value greater than zero at that point. Fix this by setting "nr_pages" to 0 when we fail to allocate memory for the "pages" pointer. Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=201119 Fixes: 771ed689 ("Btrfs: Optimize compressed writeback and reads") CC: stable@vger.kernel.org # 4.4+ Reviewed-by:
Liu Bo <bo.liu@linux.alibaba.com> Signed-off-by:
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- 15 Oct, 2018 26 commits
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Lu Fengqi authored
Using bool is more suitable than int here, and add the comment about the return_bigger. Signed-off-by:
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Lu Fengqi authored
The avg_delayed_ref_runtime can be referenced from the transaction handle. Signed-off-by:
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Lu Fengqi authored
It can be referenced from the transaction handle. Signed-off-by:
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Lu Fengqi authored
Since trans is only used for referring to delayed_refs, there is no need to pass it instead of delayed_refs to btrfs_delayed_ref_lock(). No functional change. Reviewed-by:
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Lu Fengqi authored
Since trans is only used for referring to delayed_refs, there is no need to pass it instead of delayed_refs to btrfs_select_ref_head(). No functional change. Signed-off-by:
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Lu Fengqi authored
There is no reason to put this check in (!qgroup)'s else branch because if qgroup is null, it will goto out directly. So move it out to reduce indentation level. No functional change. Signed-off-by:
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Qu Wenruo authored
Commit 581c1760 ("btrfs: Validate child tree block's level and first key") has made tree block level check mandatory. So if tree block level doesn't match, we won't get a valid extent buffer. The extra WARN_ON() check can be removed completely. Reviewed-by:
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Qu Wenruo authored
And add one line comment explaining what we're doing for each loop. Reviewed-by:
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Qu Wenruo authored
Some qgroup trace events like btrfs_qgroup_release_data() and btrfs_qgroup_free_delayed_ref() can still be triggered even if qgroup is not enabled. This is caused by the lack of qgroup status check before calling some qgroup functions. Thankfully the functions can handle quota disabled case well and just do nothing for qgroup disabled case. This patch will do earlier check before triggering related trace events. And for enabled <-> disabled race case: 1) For enabled->disabled case Disable will wipe out all qgroups data including reservation and excl/rfer. Even if we leak some reservation or numbers, it will still be cleared, so nothing will go wrong. 2) For disabled -> enabled case Current btrfs_qgroup_release_data() will use extent_io tree to ensure we won't underflow reservation. And for delayed_ref we use head->qgroup_reserved to record the reserved space, so in that case head->qgroup_reserved should be 0 and we won't underflow. CC: stable@vger.kernel.org # 4.14+ Reported-by:
Chris Murphy <lists@colorremedies.com> Link: https://lore.kernel.org/linux-btrfs/CAJCQCtQau7DtuUUeycCkZ36qjbKuxNzsgqJ7+sJ6W0dK_NLE3w@mail.gmail.com/Signed-off-by:
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Filipe Manana authored
In a scenario like the following: mkdir /mnt/A # inode 258 mkdir /mnt/B # inode 259 touch /mnt/B/bar # inode 260 sync mv /mnt/B/bar /mnt/A/bar mv -T /mnt/A /mnt/B fsync /mnt/B/bar <power fail> After replaying the log we end up with file bar having 2 hard links, both with the name 'bar' and one in the directory with inode number 258 and the other in the directory with inode number 259. Also, we end up with the directory inode 259 still existing and with the directory inode 258 still named as 'A', instead of 'B'. In this scenario, file 'bar' should only have one hard link, located at directory inode 258, the directory inode 259 should not exist anymore and the name for directory inode 258 should be 'B'. This incorrect behaviour happens because when attempting to log the old parents of an inode, we skip any parents that no longer exist. Fix this by forcing a full commit if an old parent no longer exists. A test case for fstests follows soon. CC: stable@vger.kernel.org # 4.4+ Signed-off-by:
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Filipe Manana authored
When replaying a log which contains a tmpfile (which necessarily has a link count of 0) we end up calling inc_nlink(), at fs/btrfs/tree-log.c:replay_one_buffer(), which produces a warning like the following: [195191.943673] WARNING: CPU: 0 PID: 6924 at fs/inode.c:342 inc_nlink+0x33/0x40 [195191.943723] CPU: 0 PID: 6924 Comm: mount Not tainted 4.19.0-rc6-btrfs-next-38 #1 [195191.943724] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.11.2-0-gf9626ccb91-prebuilt.qemu-project.org 04/01/2014 [195191.943726] RIP: 0010:inc_nlink+0x33/0x40 [195191.943728] RSP: 0018:ffffb96e425e3870 EFLAGS: 00010246 [195191.943730] RAX: 0000000000000000 RBX: ffff8c0d1e6af4f0 RCX: 0000000000000006 [195191.943731] RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffff8c0d1e6af4f0 [195191.943731] RBP: 0000000000000097 R08: 0000000000000001 R09: 0000000000000000 [195191.943732] R10: 0000000000000000 R11: 0000000000000000 R12: ffffb96e425e3a60 [195191.943733] R13: ffff8c0d10cff0c8 R14: ffff8c0d0d515348 R15: ffff8c0d78a1b3f8 [195191.943735] FS: 00007f570ee24480(0000) GS:ffff8c0dfb200000(0000) knlGS:0000000000000000 [195191.943736] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [195191.943737] CR2: 00005593286277c8 CR3: 00000000bb8f2006 CR4: 00000000003606f0 [195191.943739] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 [195191.943740] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 [195191.943741] Call Trace: [195191.943778] replay_one_buffer+0x797/0x7d0 [btrfs] [195191.943802] walk_up_log_tree+0x1c1/0x250 [btrfs] [195191.943809] ? rcu_read_lock_sched_held+0x3f/0x70 [195191.943825] walk_log_tree+0xae/0x1d0 [btrfs] [195191.943840] btrfs_recover_log_trees+0x1d7/0x4d0 [btrfs] [195191.943856] ? replay_dir_deletes+0x280/0x280 [btrfs] [195191.943870] open_ctree+0x1c3b/0x22a0 [btrfs] [195191.943887] btrfs_mount_root+0x6b4/0x800 [btrfs] [195191.943894] ? rcu_read_lock_sched_held+0x3f/0x70 [195191.943899] ? pcpu_alloc+0x55b/0x7c0 [195191.943906] ? mount_fs+0x3b/0x140 [195191.943908] mount_fs+0x3b/0x140 [195191.943912] ? __init_waitqueue_head+0x36/0x50 [195191.943916] vfs_kern_mount+0x62/0x160 [195191.943927] btrfs_mount+0x134/0x890 [btrfs] [195191.943936] ? rcu_read_lock_sched_held+0x3f/0x70 [195191.943938] ? pcpu_alloc+0x55b/0x7c0 [195191.943943] ? mount_fs+0x3b/0x140 [195191.943952] ? btrfs_remount+0x570/0x570 [btrfs] [195191.943954] mount_fs+0x3b/0x140 [195191.943956] ? __init_waitqueue_head+0x36/0x50 [195191.943960] vfs_kern_mount+0x62/0x160 [195191.943963] do_mount+0x1f9/0xd40 [195191.943967] ? memdup_user+0x4b/0x70 [195191.943971] ksys_mount+0x7e/0xd0 [195191.943974] __x64_sys_mount+0x21/0x30 [195191.943977] do_syscall_64+0x60/0x1b0 [195191.943980] entry_SYSCALL_64_after_hwframe+0x49/0xbe [195191.943983] RIP: 0033:0x7f570e4e524a [195191.943986] RSP: 002b:00007ffd83589478 EFLAGS: 00000206 ORIG_RAX: 00000000000000a5 [195191.943989] RAX: ffffffffffffffda RBX: 0000563f335b2060 RCX: 00007f570e4e524a [195191.943990] RDX: 0000563f335b2240 RSI: 0000563f335b2280 RDI: 0000563f335b2260 [195191.943992] RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000020 [195191.943993] R10: 00000000c0ed0000 R11: 0000000000000206 R12: 0000563f335b2260 [195191.943994] R13: 0000563f335b2240 R14: 0000000000000000 R15: 00000000ffffffff [195191.944002] irq event stamp: 8688 [195191.944010] hardirqs last enabled at (8687): [<ffffffff9cb004c3>] console_unlock+0x503/0x640 [195191.944012] hardirqs last disabled at (8688): [<ffffffff9ca037dd>] trace_hardirqs_off_thunk+0x1a/0x1c [195191.944018] softirqs last enabled at (8638): [<ffffffff9cc0a5d1>] __set_page_dirty_nobuffers+0x101/0x150 [195191.944020] softirqs last disabled at (8634): [<ffffffff9cc26bbe>] wb_wakeup_delayed+0x2e/0x60 [195191.944022] ---[ end trace 5d6e873a9a0b811a ]--- This happens because the inode does not have the flag I_LINKABLE set, which is a runtime only flag, not meant to be persisted, set when the inode is created through open(2) if the flag O_EXCL is not passed to it. Except for the warning, there are no other consequences (like corruptions or metadata inconsistencies). Since it's pointless to replay a tmpfile as it would be deleted in a later phase of the log replay procedure (it has a link count of 0), fix this by not logging tmpfiles and if a tmpfile is found in a log (created by a kernel without this change), skip the replay of the inode. A test case for fstests follows soon. Fixes: 471d557a ("Btrfs: fix loss of prealloc extents past i_size after fsync log replay") CC: stable@vger.kernel.org # 4.18+ Reported-by:
Martin Steigerwald <martin@lichtvoll.de> Link: https://lore.kernel.org/linux-btrfs/3666619.NTnn27ZJZE@merkaba/Signed-off-by:
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Josef Bacik authored
We don't need it, rsv->size is set once and never changes throughout its lifetime, so just use that for the reserve size. Signed-off-by:
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Josef Bacik authored
I ran into an issue where there was some reference being held on an inode that I couldn't track. This assert wasn't triggered, but it at least rules out we're doing something stupid. Reviewed-by:
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Josef Bacik authored
Allocating new chunks modifies both the extent and chunk tree, which can trigger new chunk allocations. So instead of doing list_for_each_safe, just do while (!list_empty()) so we make sure we don't exit with other pending bg's still on our list. CC: stable@vger.kernel.org # 4.4+ Reviewed-by:
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Josef Bacik authored
We need to clear the max_extent_size when we clear bits from a bitmap since it could have been from the range that contains the max_extent_size. CC: stable@vger.kernel.org # 4.4+ Reviewed-by:
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Josef Bacik authored
If we're allocating a new space cache inode it's likely going to be under a transaction handle, so we need to use memalloc_nofs_save() in order to avoid deadlocks, and more importantly lockdep messages that make xfstests fail. CC: stable@vger.kernel.org # 4.4+ Reviewed-by:
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Josef Bacik authored
We want to release the unused reservation we have since it refills the delayed refs reserve, which will make everything go smoother when running the delayed refs if we're short on our reservation. CC: stable@vger.kernel.org # 4.4+ Reviewed-by:
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Liu Bo authored
Btrfs's btree locking has two modes, spinning mode and blocking mode, while searching btree, locking is always acquired in spinning mode and then converted to blocking mode if necessary, and in some hot paths we may switch the locking back to spinning mode by btrfs_clear_path_blocking(). When acquiring locks, both of reader and writer need to wait for blocking readers and writers to complete before doing read_lock()/write_lock(). The problem is that btrfs_clear_path_blocking() needs to switch nodes in the path to blocking mode at first (by btrfs_set_path_blocking) to make lockdep happy before doing its actual clearing blocking job. When switching to blocking mode from spinning mode, it consists of step 1) bumping up blocking readers counter and step 2) read_unlock()/write_unlock(), this has caused serious ping-pong effect if there're a great amount of concurrent readers/writers, as waiters will be woken up and go to sleep immediately. 1) Killing this kind of ping-pong results in a big improvement in my 1600k files creation script, MNT=/mnt/btrfs mkfs.btrfs -f /dev/sdf mount /dev/def $MNT time fsmark -D 10000 -S0 -n 100000 -s 0 -L 1 -l /tmp/fs_log.txt \ -d $MNT/0 -d $MNT/1 \ -d $MNT/2 -d $MNT/3 \ -d $MNT/4 -d $MNT/5 \ -d $MNT/6 -d $MNT/7 \ -d $MNT/8 -d $MNT/9 \ -d $MNT/10 -d $MNT/11 \ -d $MNT/12 -d $MNT/13 \ -d $MNT/14 -d $MNT/15 w/o patch: real 2m27.307s user 0m12.839s sys 13m42.831s w/ patch: real 1m2.273s user 0m15.802s sys 8m16.495s 1.1) latency histogram from funclatency[1] Overall with the patch, there're ~50% less write lock acquisition and the 95% max latency that write lock takes also reduces to ~100ms from >500ms. -------------------------------------------- w/o patch: -------------------------------------------- Function = btrfs_tree_lock msecs : count distribution 0 -> 1 : 2385222 |****************************************| 2 -> 3 : 37147 | | 4 -> 7 : 20452 | | 8 -> 15 : 13131 | | 16 -> 31 : 3877 | | 32 -> 63 : 3900 | | 64 -> 127 : 2612 | | 128 -> 255 : 974 | | 256 -> 511 : 165 | | 512 -> 1023 : 13 | | Function = btrfs_tree_read_lock msecs : count distribution 0 -> 1 : 6743860 |****************************************| 2 -> 3 : 2146 | | 4 -> 7 : 190 | | 8 -> 15 : 38 | | 16 -> 31 : 4 | | -------------------------------------------- w/ patch: -------------------------------------------- Function = btrfs_tree_lock msecs : count distribution 0 -> 1 : 1318454 |****************************************| 2 -> 3 : 6800 | | 4 -> 7 : 3664 | | 8 -> 15 : 2145 | | 16 -> 31 : 809 | | 32 -> 63 : 219 | | 64 -> 127 : 10 | | Function = btrfs_tree_read_lock msecs : count distribution 0 -> 1 : 6854317 |****************************************| 2 -> 3 : 2383 | | 4 -> 7 : 601 | | 8 -> 15 : 92 | | 2) dbench also proves the improvement, dbench -t 120 -D /mnt/btrfs 16 w/o patch: Throughput 158.363 MB/sec w/ patch: Throughput 449.52 MB/sec 3) xfstests didn't show any additional failures. One thing to note is that callers may set path->leave_spinning to have all nodes in the path stay in spinning mode, which means callers are ready to not sleep before releasing the path, but it won't cause problems if they don't want to sleep in blocking mode. [1]: https://github.com/iovisor/bcc/blob/master/tools/funclatency.pySigned-off-by: -
David Sterba authored
The value of blocking_readers is increased only when the lock is taken for read, no way we can fail the condition with the write lock. Reviewed-by:
Anand Jain <anand.jain@oracle.com> Signed-off-by:
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David Sterba authored
The replace_wait and bio_counter were mistakenly added to fs_info in commit c404e0dc ("Btrfs: fix use-after-free in the finishing procedure of the device replace"), but they logically belong to fs_info::dev_replace. Besides, bio_counter is a very generic name and is confusing in bare fs_info context. Reviewed-by:
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David Sterba authored
The exit sequence in btrfs_dev_replace_start does not allow to simply add a label to the right place so the error handling after starting transaction failure jumps there. Currently there's a lock that pairs with the unlock in the section, which is unnecessary and only raises questions. Add a variable to track the locking status and avoid the extra locking. Reviewed-by:
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David Sterba authored
Too trivial, the purpose can be simply documented in a comment. Reviewed-by:
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David Sterba authored
The wrapper is too trivial, open coding does not make it less readable. Reviewed-by:
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David Sterba authored
There's a single caller and the function name does not say it's actually taking the lock, so open coding makes it more explicit. For now, btrfs_dev_replace_read_lock is used instead of read_lock so it's paired with the unlocking wrapper in the same block. Reviewed-by:
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David Sterba authored
This member seems to be copied from the extent_buffer locking scheme and is at least used to assert that the read lock/unlock is properly nested. In some way. While the _inc/_dec are called inside the read lock section, the asserts are both inside and outside, so the ordering is not guaranteed and we can see read/inc/dec ordered in any way (theoretically). A missing call of btrfs_dev_replace_clear_lock_blocking could cause unexpected read_locks count, so this at least looks like a valid assertion, but this will become unnecessary with later updates. Reviewed-by:
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Qu Wenruo authored
Although we have tree level check at tree read runtime, it's completely based on its parent level. We still need to do accurate level check to avoid invalid tree blocks sneak into kernel space. The check itself is simple, for leaf its level should always be 0. For nodes its level should be in range [1, BTRFS_MAX_LEVEL - 1]. Signed-off-by:
Su Yue <suy.fnst@cn.fujitsu.com> Reviewed-by:
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