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2018-10-19btrfs: move the dio_sem higher up the callchainJosef Bacik1-2/+0
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: Filipe Manana <fdmanana@suse.com> Signed-off-by: Josef Bacik <josef@toxicpanda.com> Signed-off-by: David Sterba <dsterba@suse.com>
2018-10-17Btrfs: fix assertion on fsync of regular file when using no-holes featureFilipe Manana1-1/+2
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: a89ca6f24ffe ("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: Filipe Manana <fdmanana@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2018-10-15Btrfs: fix wrong dentries after fsync of file that got its parent replacedFilipe Manana1-3/+27
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: Filipe Manana <fdmanana@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2018-10-15Btrfs: fix warning when replaying log after fsync of a tmpfileFilipe Manana1-10/+32
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: 471d557afed1 ("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: Filipe Manana <fdmanana@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2018-10-15btrfs: fix error handling in free_log_treeJeff Mahoney1-3/+6
When we hit an I/O error in free_log_tree->walk_log_tree during file system shutdown we can crash due to there not being a valid transaction handle. Use btrfs_handle_fs_error when there's no transaction handle to use. BUG: unable to handle kernel NULL pointer dereference at 0000000000000060 IP: free_log_tree+0xd2/0x140 [btrfs] PGD 0 P4D 0 Oops: 0000 [#1] SMP DEBUG_PAGEALLOC PTI Modules linked in: <modules> CPU: 2 PID: 23544 Comm: umount Tainted: G W 4.12.14-kvmsmall #9 SLE15 (unreleased) Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.0.0-prebuilt.qemu-project.org 04/01/2014 task: ffff96bfd3478880 task.stack: ffffa7cf40d78000 RIP: 0010:free_log_tree+0xd2/0x140 [btrfs] RSP: 0018:ffffa7cf40d7bd10 EFLAGS: 00010282 RAX: 00000000fffffffb RBX: 00000000fffffffb RCX: 0000000000000002 RDX: 0000000000000000 RSI: ffff96c02f07d4c8 RDI: 0000000000000282 RBP: ffff96c013cf1000 R08: ffff96c02f07d4c8 R09: ffff96c02f07d4d0 R10: 0000000000000000 R11: 0000000000000002 R12: 0000000000000000 R13: ffff96c005e800c0 R14: ffffa7cf40d7bdb8 R15: 0000000000000000 FS: 00007f17856bcfc0(0000) GS:ffff96c03f600000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000000000060 CR3: 0000000045ed6002 CR4: 00000000003606e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: ? wait_for_writer+0xb0/0xb0 [btrfs] btrfs_free_log+0x17/0x30 [btrfs] btrfs_drop_and_free_fs_root+0x9a/0xe0 [btrfs] btrfs_free_fs_roots+0xc0/0x130 [btrfs] ? wait_for_completion+0xf2/0x100 close_ctree+0xea/0x2e0 [btrfs] ? kthread_stop+0x161/0x260 generic_shutdown_super+0x6c/0x120 kill_anon_super+0xe/0x20 btrfs_kill_super+0x13/0x100 [btrfs] deactivate_locked_super+0x3f/0x70 cleanup_mnt+0x3b/0x70 task_work_run+0x78/0x90 exit_to_usermode_loop+0x77/0xa6 do_syscall_64+0x1c5/0x1e0 entry_SYSCALL_64_after_hwframe+0x42/0xb7 RIP: 0033:0x7f1784f90827 RSP: 002b:00007ffdeeb03118 EFLAGS: 00000246 ORIG_RAX: 00000000000000a6 RAX: 0000000000000000 RBX: 0000556a60c62970 RCX: 00007f1784f90827 RDX: 0000000000000001 RSI: 0000000000000000 RDI: 0000556a60c62b50 RBP: 0000000000000000 R08: 0000000000000005 R09: 00000000ffffffff R10: 0000556a60c63900 R11: 0000000000000246 R12: 0000556a60c62b50 R13: 00007f17854a81c4 R14: 0000000000000000 R15: 0000000000000000 RIP: free_log_tree+0xd2/0x140 [btrfs] RSP: ffffa7cf40d7bd10 CR2: 0000000000000060 Fixes: 681ae50917df9 ("Btrfs: cleanup reserved space when freeing tree log on error") CC: <stable@vger.kernel.org> # v3.13 Signed-off-by: Jeff Mahoney <jeffm@suse.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2018-10-15btrfs: change btrfs_pin_log_trans to return voidzhong jiang1-4/+1
btrfs_pin_log_trans defines the variable "ret" for return value, but it is not modified after initialization. Further, I find that none of the callers do handles the return value, so it is safe to drop the unneeded "ret" and make it return void. Signed-off-by: zhong jiang <zhongjiang@huawei.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2018-08-23Btrfs: sync log after logging new nameFilipe Manana1-6/+42
When we add a new name for an inode which was logged in the current transaction, we update the inode in the log so that its new name and ancestors are added to the log. However when we do this we do not persist the log, so the changes remain in memory only, and as a consequence, any ancestors that were created in the current transaction are updated such that future calls to btrfs_inode_in_log() return true. This leads to a subsequent fsync against such new ancestor directories returning immediately, without persisting the log, therefore after a power failure the new ancestor directories do not exist, despite fsync being called against them explicitly. Example: $ mkfs.btrfs -f /dev/sdb $ mount /dev/sdb /mnt $ mkdir /mnt/A $ mkdir /mnt/B $ mkdir /mnt/A/C $ touch /mnt/B/foo $ xfs_io -c "fsync" /mnt/B/foo $ ln /mnt/B/foo /mnt/A/C/foo $ xfs_io -c "fsync" /mnt/A <power failure> After the power failure, directory "A" does not exist, despite the explicit fsync on it. Instead of fixing this by changing the behaviour of the explicit fsync on directory "A" to persist the log instead of doing nothing, make the logging of the new file name (which happens when creating a hard link or renaming) persist the log. This approach not only is simpler, not requiring addition of new fields to the inode in memory structure, but also gives us the same behaviour as ext4, xfs and f2fs (possibly other filesystems too). A test case for fstests follows soon. Fixes: 12fcfd22fe5b ("Btrfs: tree logging unlink/rename fixes") Reported-by: Vijay Chidambaram <vvijay03@gmail.com> Signed-off-by: Filipe Manana <fdmanana@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2018-08-06btrfs: simplify IS_ERR/PTR_ERR checksAl Viro1-3/+2
IS_ERR(p) && PTR_ERR(p) == n is a weird way to spell p == ERR_PTR(n). Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Reviewed-by: David Sterba <dsterba@suse.com> Reviewed-by: Nikolay Borisov <nborisov@suse.com> [ update changelog ] Signed-off-by: David Sterba <dsterba@suse.com>
2018-08-06btrfs: btrfs_iget never returns an is_bad_inode inodeAl Viro1-5/+1
Just get rid of pointless checks. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Reviewed-by: Nikolay Borisov <nborisov@suse.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2018-08-06Btrfs: fix mount failure after fsync due to hard link recreationFilipe Manana1-0/+66
If we end up with logging an inode reference item which has the same name but different index from the one we have persisted, we end up failing when replaying the log with an errno value of -EEXIST. The error comes from btrfs_add_link(), which is called from add_inode_ref(), when we are replaying an inode reference item. Example scenario where this happens: $ mkfs.btrfs -f /dev/sdb $ mount /dev/sdb /mnt $ touch /mnt/foo $ ln /mnt/foo /mnt/bar $ sync # Rename the first hard link (foo) to a new name and rename the second # hard link (bar) to the old name of the first hard link (foo). $ mv /mnt/foo /mnt/qwerty $ mv /mnt/bar /mnt/foo # Create a new file, in the same parent directory, with the old name of # the second hard link (bar) and fsync this new file. # We do this instead of calling fsync on foo/qwerty because if we did # that the fsync resulted in a full transaction commit, not triggering # the problem. $ touch /mnt/bar $ xfs_io -c "fsync" /mnt/bar <power fail> $ mount /dev/sdb /mnt mount: mount /dev/sdb on /mnt failed: File exists So fix this by checking if a conflicting inode reference exists (same name, same parent but different index), removing it (and the associated dir index entries from the parent inode) if it exists, before attempting to add the new reference. A test case for fstests follows soon. CC: stable@vger.kernel.org # 4.4+ Signed-off-by: Filipe Manana <fdmanana@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2018-08-06btrfs: qgroup: Drop fs_info parameter from btrfs_qgroup_trace_extentLu Fengqi1-1/+1
It can be fetched from the transaction handle. In addition, remove the WARN_ON(trans == NULL) because it's not possible to hit this condition. Signed-off-by: Lu Fengqi <lufq.fnst@cn.fujitsu.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2018-08-06btrfs: simplify pointer chasing of local fs_info variablesDavid Sterba1-3/+3
Functions that get btrfs inode can simply reach the fs_info by dereferencing the root and this looks a bit more straightforward compared to the btrfs_sb(...) indirection. If the transaction handle is available and not NULL it's used instead. Signed-off-by: David Sterba <dsterba@suse.com>
2018-08-06btrfs: Get rid of the confusing btrfs_file_extent_inline_lenQu Wenruo1-8/+4
We used to call btrfs_file_extent_inline_len() to get the uncompressed data size of an inlined extent. However this function is hiding evil, for compressed extent, it has no choice but to directly read out ram_bytes from btrfs_file_extent_item. While for uncompressed extent, it uses item size to calculate the real data size, and ignoring ram_bytes completely. In fact, for corrupted ram_bytes, due to above behavior kernel btrfs_print_leaf() can't even print correct ram_bytes to expose the bug. Since we have the tree-checker to verify all EXTENT_DATA, such mismatch can be detected pretty easily, thus we can trust ram_bytes without the evil btrfs_file_extent_inline_len(). Signed-off-by: Qu Wenruo <wqu@suse.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2018-08-06btrfs: Remove fs_info from btrfs_alloc_logged_file_extentNikolay Borisov1-1/+0
It can be referenced from trans since the function is always called within a valid transaction. Signed-off-by: Nikolay Borisov <nborisov@suse.com> Reviewed-by: Qu Wenruo <wqu@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2018-08-06btrfs: Streamline log_extent_csums a bitNikolay Borisov1-6/+4
Currently this function takes the root as an argument only to get the log_root from it. Simplify this by directly passing the log root from the caller. Also eliminate the fs_info local variable, since it's used only once, so directly reference it from the transaction handle. Signed-off-by: Nikolay Borisov <nborisov@suse.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2018-08-06btrfs: remove the logged extents infrastructureJosef Bacik1-16/+0
This is no longer used anywhere, remove all of it. Signed-off-by: Josef Bacik <jbacik@fb.com> Reviewed-by: Filipe Manana <fdmanana@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2018-08-06btrfs: clean up the left over logged_list usageJosef Bacik1-30/+2
We no longer use this list we've passed around so remove it everywhere. Also remove the extra checks for ordered/filemap errors as this is handled higher up now that we're waiting on ordered_extents before getting to the tree log code. Signed-off-by: Josef Bacik <jbacik@fb.com> Reviewed-by: Filipe Manana <fdmanana@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2018-08-06btrfs: remove the wait ordered logic in the log_one_extent pathJosef Bacik1-108/+10
Since we are waiting on all ordered extents at the start of the fsync() path we don't need to wait on any logged ordered extents, and we don't need to look up the checksums on the ordered extents as they will already be on disk prior to getting here. Rework this so we're only looking up and copying the on-disk checksums for the extent range we care about. Signed-off-by: Josef Bacik <jbacik@fb.com> Reviewed-by: Filipe Manana <fdmanana@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2018-05-28btrfs: replace waitqueue_actvie with cond_wake_upDavid Sterba1-22/+12
Use the wrappers and reduce the amount of low-level details about the waitqueue management. Reviewed-by: Nikolay Borisov <nborisov@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2018-05-28btrfs: add barriers to btrfs_sync_log before log_commit_wait wakeupsDavid Sterba1-2/+8
Currently the code assumes that there's an implied barrier by the sequence of code preceding the wakeup, namely the mutex unlock. As Nikolay pointed out: I think this is wrong (not your code) but the original assumption that the RELEASE semantics provided by mutex_unlock is sufficient. According to memory-barriers.txt: Section 'LOCK ACQUISITION FUNCTIONS' states: (2) RELEASE operation implication: Memory operations issued before the RELEASE will be completed before the RELEASE operation has completed. Memory operations issued after the RELEASE *may* be completed before the RELEASE operation has completed. (I've bolded the may portion) The example given there: As an example, consider the following: *A = a; *B = b; ACQUIRE *C = c; *D = d; RELEASE *E = e; *F = f; The following sequence of events is acceptable: ACQUIRE, {*F,*A}, *E, {*C,*D}, *B, RELEASE So if we assume that *C is modifying the flag which the waitqueue is checking, and *E is the actual wakeup, then those accesses can be re-ordered... IMHO this code should be considered broken... --- To be on the safe side, add the barriers. The synchronization logic around log using the mutexes and several other threads does not make it easy to reason for/against the barrier. CC: Nikolay Borisov <nborisov@suse.com> Link: https://lkml.kernel.org/r/6ee068d8-1a69-3728-00d1-d86293d43c9f@suse.com Reviewed-by: Nikolay Borisov <nborisov@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2018-05-17Btrfs: fix duplicate extents after fsync of file with prealloc extentsFilipe Manana1-25/+112
In commit 471d557afed1 ("Btrfs: fix loss of prealloc extents past i_size after fsync log replay"), on fsync, we started to always log all prealloc extents beyond an inode's i_size in order to avoid losing them after a power failure. However under some cases this can lead to the log replay code to create duplicate extent items, with different lengths, in the extent tree. That happens because, as of that commit, we can now log extent items based on extent maps that are not on the "modified" list of extent maps of the inode's extent map tree. Logging extent items based on extent maps is used during the fast fsync path to save time and for this to work reliably it requires that the extent maps are not merged with other adjacent extent maps - having the extent maps in the list of modified extents gives such guarantee. Consider the following example, captured during a long run of fsstress, which illustrates this problem. We have inode 271, in the filesystem tree (root 5), for which all of the following operations and discussion apply to. A buffered write starts at offset 312391 with a length of 933471 bytes (end offset at 1245862). At this point we have, for this inode, the following extent maps with the their field values: em A, start 0, orig_start 0, len 40960, block_start 18446744073709551613, block_len 0, orig_block_len 0 em B, start 40960, orig_start 40960, len 376832, block_start 1106399232, block_len 376832, orig_block_len 376832 em C, start 417792, orig_start 417792, len 782336, block_start 18446744073709551613, block_len 0, orig_block_len 0 em D, start 1200128, orig_start 1200128, len 835584, block_start 1106776064, block_len 835584, orig_block_len 835584 em E, start 2035712, orig_start 2035712, len 245760, block_start 1107611648, block_len 245760, orig_block_len 245760 Extent map A corresponds to a hole and extent maps D and E correspond to preallocated extents. Extent map D ends where extent map E begins (1106776064 + 835584 = 1107611648), but these extent maps were not merged because they are in the inode's list of modified extent maps. An fsync against this inode is made, which triggers the fast path (BTRFS_INODE_NEEDS_FULL_SYNC is not set). This fsync triggers writeback of the data previously written using buffered IO, and when the respective ordered extent finishes, btrfs_drop_extents() is called against the (aligned) range 311296..1249279. This causes a split of extent map D at btrfs_drop_extent_cache(), replacing extent map D with a new extent map D', also added to the list of modified extents, with the following values: em D', start 1249280, orig_start of 1200128, block_start 1106825216 (= 1106776064 + 1249280 - 1200128), orig_block_len 835584, block_len 786432 (835584 - (1249280 - 1200128)) Then, during the fast fsync, btrfs_log_changed_extents() is called and extent maps D' and E are removed from the list of modified extents. The flag EXTENT_FLAG_LOGGING is also set on them. After the extents are logged clear_em_logging() is called on each of them, and that makes extent map E to be merged with extent map D' (try_merge_map()), resulting in D' being deleted and E adjusted to: em E, start 1249280, orig_start 1200128, len 1032192, block_start 1106825216, block_len 1032192, orig_block_len 245760 A direct IO write at offset 1847296 and length of 360448 bytes (end offset at 2207744) starts, and at that moment the following extent maps exist for our inode: em A, start 0, orig_start 0, len 40960, block_start 18446744073709551613, block_len 0, orig_block_len 0 em B, start 40960, orig_start 40960, len 270336, block_start 1106399232, block_len 270336, orig_block_len 376832 em C, start 311296, orig_start 311296, len 937984, block_start 1112842240, block_len 937984, orig_block_len 937984 em E (prealloc), start 1249280, orig_start 1200128, len 1032192, block_start 1106825216, block_len 1032192, orig_block_len 245760 The dio write results in drop_extent_cache() being called twice. The first time for a range that starts at offset 1847296 and ends at offset 2035711 (length of 188416), which results in a double split of extent map E, replacing it with two new extent maps: em F, start 1249280, orig_start 1200128, block_start 1106825216, block_len 598016, orig_block_len 598016 em G, start 2035712, orig_start 1200128, block_start 1107611648, block_len 245760, orig_block_len 1032192 It also creates a new extent map that represents a part of the requested IO (through create_io_em()): em H, start 1847296, len 188416, block_start 1107423232, block_len 188416 The second call to drop_extent_cache() has a range with a start offset of 2035712 and end offset of 2207743 (length of 172032). This leads to replacing extent map G with a new extent map I with the following values: em I, start 2207744, orig_start 1200128, block_start 1107783680, block_len 73728, orig_block_len 1032192 It also creates a new extent map that represents the second part of the requested IO (through create_io_em()): em J, start 2035712, len 172032, block_start 1107611648, block_len 172032 The dio write set the inode's i_size to 2207744 bytes. After the dio write the inode has the following extent maps: em A, start 0, orig_start 0, len 40960, block_start 18446744073709551613, block_len 0, orig_block_len 0 em B, start 40960, orig_start 40960, len 270336, block_start 1106399232, block_len 270336, orig_block_len 376832 em C, start 311296, orig_start 311296, len 937984, block_start 1112842240, block_len 937984, orig_block_len 937984 em F, start 1249280, orig_start 1200128, len 598016, block_start 1106825216, block_len 598016, orig_block_len 598016 em H, start 1847296, orig_start 1200128, len 188416, block_start 1107423232, block_len 188416, orig_block_len 835584 em J, start 2035712, orig_start 2035712, len 172032, block_start 1107611648, block_len 172032, orig_block_len 245760 em I, start 2207744, orig_start 1200128, len 73728, block_start 1107783680, block_len 73728, orig_block_len 1032192 Now do some change to the file, like adding a xattr for example and then fsync it again. This triggers a fast fsync path, and as of commit 471d557afed1 ("Btrfs: fix loss of prealloc extents past i_size after fsync log replay"), we use the extent map I to log a file extent item because it's a prealloc extent and it starts at an offset matching the inode's i_size. However when we log it, we create a file extent item with a value for the disk byte location that is wrong, as can be seen from the following output of "btrfs inspect-internal dump-tree": item 1 key (271 EXTENT_DATA 2207744) itemoff 3782 itemsize 53 generation 22 type 2 (prealloc) prealloc data disk byte 1106776064 nr 1032192 prealloc data offset 1007616 nr 73728 Here the disk byte value corresponds to calculation based on some fields from the extent map I: 1106776064 = block_start (1107783680) - 1007616 (extent_offset) extent_offset = 2207744 (start) - 1200128 (orig_start) = 1007616 The disk byte value of 1106776064 clashes with disk byte values of the file extent items at offsets 1249280 and 1847296 in the fs tree: item 6 key (271 EXTENT_DATA 1249280) itemoff 3568 itemsize 53 generation 20 type 2 (prealloc) prealloc data disk byte 1106776064 nr 835584 prealloc data offset 49152 nr 598016 item 7 key (271 EXTENT_DATA 1847296) itemoff 3515 itemsize 53 generation 20 type 1 (regular) extent data disk byte 1106776064 nr 835584 extent data offset 647168 nr 188416 ram 835584 extent compression 0 (none) item 8 key (271 EXTENT_DATA 2035712) itemoff 3462 itemsize 53 generation 20 type 1 (regular) extent data disk byte 1107611648 nr 245760 extent data offset 0 nr 172032 ram 245760 extent compression 0 (none) item 9 key (271 EXTENT_DATA 2207744) itemoff 3409 itemsize 53 generation 20 type 2 (prealloc) prealloc data disk byte 1107611648 nr 245760 prealloc data offset 172032 nr 73728 Instead of the disk byte value of 1106776064, the value of 1107611648 should have been logged. Also the data offset value should have been 172032 and not 1007616. After a log replay we end up getting two extent items in the extent tree with different lengths, one of 835584, which is correct and existed before the log replay, and another one of 1032192 which is wrong and is based on the logged file extent item: item 12 key (1106776064 EXTENT_ITEM 835584) itemoff 3406 itemsize 53 refs 2 gen 15 flags DATA extent data backref root 5 objectid 271 offset 1200128 count 2 item 13 key (1106776064 EXTENT_ITEM 1032192) itemoff 3353 itemsize 53 refs 1 gen 22 flags DATA extent data backref root 5 objectid 271 offset 1200128 count 1 Obviously this leads to many problems and a filesystem check reports many errors: (...) checking extents Extent back ref already exists for 1106776064 parent 0 root 5 owner 271 offset 1200128 num_refs 1 extent item 1106776064 has multiple extent items ref mismatch on [1106776064 835584] extent item 2, found 3 Incorrect local backref count on 1106776064 root 5 owner 271 offset 1200128 found 2 wanted 1 back 0x55b1d0ad7680 Backref 1106776064 root 5 owner 271 offset 1200128 num_refs 0 not found in extent tree Incorrect local backref count on 1106776064 root 5 owner 271 offset 1200128 found 1 wanted 0 back 0x55b1d0ad4e70 Backref bytes do not match extent backref, bytenr=1106776064, ref bytes=835584, backref bytes=1032192 backpointer mismatch on [1106776064 835584] checking free space cache block group 1103101952 has wrong amount of free space failed to load free space cache for block group 1103101952 checking fs roots (...) So fix this by logging the prealloc extents beyond the inode's i_size based on searches in the subvolume tree instead of the extent maps. Fixes: 471d557afed1 ("Btrfs: fix loss of prealloc extents past i_size after fsync log replay") CC: stable@vger.kernel.org # 4.14+ Signed-off-by: Filipe Manana <fdmanana@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2018-05-14Btrfs: fix xattr loss after power failureFilipe Manana1-0/+7
If a file has xattrs, we fsync it, to ensure we clear the flags BTRFS_INODE_NEEDS_FULL_SYNC and BTRFS_INODE_COPY_EVERYTHING from its inode, the current transaction commits and then we fsync it (without either of those bits being set in its inode), we end up not logging all its xattrs. This results in deleting all xattrs when replying the log after a power failure. Trivial reproducer $ mkfs.btrfs -f /dev/sdb $ mount /dev/sdb /mnt $ touch /mnt/foobar $ setfattr -n user.xa -v qwerty /mnt/foobar $ xfs_io -c "fsync" /mnt/foobar $ sync $ xfs_io -c "pwrite -S 0xab 0 64K" /mnt/foobar $ xfs_io -c "fsync" /mnt/foobar <power failure> $ mount /dev/sdb /mnt $ getfattr --absolute-names --dump /mnt/foobar <empty output> $ So fix this by making sure all xattrs are logged if we log a file's inode item and neither the flags BTRFS_INODE_NEEDS_FULL_SYNC nor BTRFS_INODE_COPY_EVERYTHING were set in the inode. Fixes: 36283bf777d9 ("Btrfs: fix fsync xattr loss in the fast fsync path") Cc: <stable@vger.kernel.org> # 4.2+ Signed-off-by: Filipe Manana <fdmanana@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2018-04-12btrfs: replace GPL boilerplate by SPDX -- sourcesDavid Sterba1-14/+1
Remove GPL boilerplate text (long, short, one-line) and keep the rest, ie. personal, company or original source copyright statements. Add the SPDX header. Signed-off-by: David Sterba <dsterba@suse.com>
2018-04-12Btrfs: fix loss of prealloc extents past i_size after fsync log replayFilipe Manana1-5/+58
Currently if we allocate extents beyond an inode's i_size (through the fallocate system call) and then fsync the file, we log the extents but after a power failure we replay them and then immediately drop them. This behaviour happens since about 2009, commit c71bf099abdd ("Btrfs: Avoid orphan inodes cleanup while replaying log"), because it marks the inode as an orphan instead of dropping any extents beyond i_size before replaying logged extents, so after the log replay, and while the mount operation is still ongoing, we find the inode marked as an orphan and then perform a truncation (drop extents beyond the inode's i_size). Because the processing of orphan inodes is still done right after replaying the log and before the mount operation finishes, the intention of that commit does not make any sense (at least as of today). However reverting that behaviour is not enough, because we can not simply discard all extents beyond i_size and then replay logged extents, because we risk dropping extents beyond i_size created in past transactions, for example: add prealloc extent beyond i_size fsync - clears the flag BTRFS_INODE_NEEDS_FULL_SYNC from the inode transaction commit add another prealloc extent beyond i_size fsync - triggers the fast fsync path power failure In that scenario, we would drop the first extent and then replay the second one. To fix this just make sure that all prealloc extents beyond i_size are logged, and if we find too many (which is far from a common case), fallback to a full transaction commit (like we do when logging regular extents in the fast fsync path). Trivial reproducer: $ mkfs.btrfs -f /dev/sdb $ mount /dev/sdb /mnt $ xfs_io -f -c "pwrite -S 0xab 0 256K" /mnt/foo $ sync $ xfs_io -c "falloc -k 256K 1M" /mnt/foo $ xfs_io -c "fsync" /mnt/foo <power failure> # mount to replay log $ mount /dev/sdb /mnt # at this point the file only has one extent, at offset 0, size 256K A test case for fstests follows soon, covering multiple scenarios that involve adding prealloc extents with previous shrinking truncates and without such truncates. Fixes: c71bf099abdd ("Btrfs: Avoid orphan inodes cleanup while replaying log") Signed-off-by: Filipe Manana <fdmanana@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2018-04-05Btrfs: bail out on error during replay_dir_deletesLiu Bo1-1/+3
If errors were returned by btrfs_next_leaf(), replay_dir_deletes needs to bail out, otherwise @ret would be forced to be 0 after 'break;' and the caller won't be aware of it. Fixes: e02119d5a7b4 ("Btrfs: Add a write ahead tree log to optimize synchronous operations") Reviewed-by: Nikolay Borisov <nborisov@suse.com> Signed-off-by: Liu Bo <bo.liu@linux.alibaba.com> Signed-off-by: David Sterba <dsterba@suse.com>
2018-04-05Btrfs: fix NULL pointer dereference in log_dir_itemsLiu Bo1-2/+5
0, 1 and <0 can be returned by btrfs_next_leaf(), and when <0 is returned, path->nodes[0] could be NULL, log_dir_items lacks such a check for <0 and we may run into a null pointer dereference panic. Fixes: e02119d5a7b4 ("Btrfs: Add a write ahead tree log to optimize synchronous operations") Reviewed-by: Nikolay Borisov <nborisov@suse.com> Signed-off-by: Liu Bo <bo.liu@linux.alibaba.com> Signed-off-by: David Sterba <dsterba@suse.com>
2018-03-31btrfs: Validate child tree block's level and first keyQu Wenruo1-11/+17
We have several reports about node pointer points to incorrect child tree blocks, which could have even wrong owner and level but still with valid generation and checksum. Although btrfs check could handle it and print error message like: leaf parent key incorrect 60670574592 Kernel doesn't have enough check on this type of corruption correctly. At least add such check to read_tree_block() and btrfs_read_buffer(), where we need two new parameters @level and @first_key to verify the child tree block. The new @level check is mandatory and all call sites are already modified to extract expected level from its call chain. While @first_key is optional, the following call sites are skipping such check: 1) Root node/leaf As ROOT_ITEM doesn't contain the first key, skip @first_key check. 2) Direct backref Only parent bytenr and level is known and we need to resolve the key all by ourselves, skip @first_key check. Another note of this verification is, it needs extra info from nodeptr or ROOT_ITEM, so it can't fit into current tree-checker framework, which is limited to node/leaf boundary. Signed-off-by: Qu Wenruo <wqu@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2018-03-31Btrfs: fix copy_items() return value when logging an inodeFilipe Manana1-0/+1
When logging an inode, at tree-log.c:copy_items(), if we call btrfs_next_leaf() at the loop which checks for the need to log holes, we need to make sure copy_items() returns the value 1 to its caller and not 0 (on success). This is because the path the caller passed was released and is now different from what is was before, and the caller expects a return value of 0 to mean both success and that the path has not changed, while a return value of 1 means both success and signals the caller that it can not reuse the path, it has to perform another tree search. Even though this is a case that should not be triggered on normal circumstances or very rare at least, its consequences can be very unpredictable (especially when replaying a log tree). Fixes: 16e7549f045d ("Btrfs: incompatible format change to remove hole extents") Signed-off-by: Filipe Manana <fdmanana@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2018-03-31Btrfs: fix fsync after hole punching when using no-holes featureFilipe Manana1-0/+30
When we have the no-holes mode enabled and fsync a file after punching a hole in it, we can end up not logging the whole hole range in the log tree. This happens if the file has extent items that span more than one leaf and we punch a hole that covers a range that starts in a leaf but does not go beyond the offset of the first extent in the next leaf. Example: $ mkfs.btrfs -f -O no-holes -n 65536 /dev/sdb $ mount /dev/sdb /mnt $ for ((i = 0; i <= 831; i++)); do offset=$((i * 2 * 256 * 1024)) xfs_io -f -c "pwrite -S 0xab -b 256K $offset 256K" \ /mnt/foobar >/dev/null done $ sync # We now have 2 leafs in our filesystem fs tree, the first leaf has an # item corresponding the extent at file offset 216530944 and the second # leaf has a first item corresponding to the extent at offset 217055232. # Now we punch a hole that partially covers the range of the extent at # offset 216530944 but does go beyond the offset 217055232. $ xfs_io -c "fpunch $((216530944 + 128 * 1024 - 4000)) 256K" /mnt/foobar $ xfs_io -c "fsync" /mnt/foobar <power fail> # mount to replay the log $ mount /dev/sdb /mnt # Before this patch, only the subrange [216658016, 216662016[ (length of # 4000 bytes) was logged, leaving an incorrect file layout after log # replay. Fix this by checking if there is a hole between the last extent item that we processed and the first extent item in the next leaf, and if there is one, log an explicit hole extent item. Fixes: 16e7549f045d ("Btrfs: incompatible format change to remove hole extents") Signed-off-by: Filipe Manana <fdmanana@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2018-03-26btrfs: Remove root argument from btrfs_log_dentry_safeNikolay Borisov1-1/+1
Now that nothing uses the root arg of btrfs_log_dentry_safe it can be safely removed. No functional changes. Signed-off-by: Nikolay Borisov <nborisov@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2018-03-26btrfs: Remove root arg from btrfs_log_inode_parentNikolay Borisov1-7/+6
btrfs_log_inode_parent is called from 2 places (btrfs_log_dentry_safe and btrfs_log_new_name) both of which pass inode->root as the root argument and the inode itself. Remove the redundant root argument and get a reference to the root directly from the inode, also remove redundant root != inode->root check from the same function. No functional change. Signed-off-by: Nikolay Borisov <nborisov@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2018-03-26btrfs: Remove custom crc32c init codeNikolay Borisov1-1/+1
The custom crc32 init code was introduced in 14a958e678cd ("Btrfs: fix btrfs boot when compiled as built-in") to enable using btrfs as a built-in. However, later as pointed out by 60efa5eb2e88 ("Btrfs: use late_initcall instead of module_init") this wasn't enough and finally btrfs was switched to late_initcall which comes after the generic crc32c implementation is initiliased. The latter commit superseeded the former. Now that we don't have to maintain our own code let's just remove it and switch to using the generic implementation. Despite touching a lot of files the patch is really simple. Here is the gist of the changes: 1. Select LIBCRC32C rather than the low-level modules. 2. s/btrfs_crc32c/crc32c/g 3. replace hash.h with linux/crc32c.h 4. Move the btrfs namehash funcs to ctree.h and change the tree accordingly. I've tested this with btrfs being both a module and a built-in and xfstest doesn't complain. Does seem to fix the longstanding problem of not automatically selectiong the crc32c module when btrfs is used. Possibly there is a workaround in dracut. The modinfo confirms that now all the module dependencies are there: before: depends: zstd_compress,zstd_decompress,raid6_pq,xor,zlib_deflate after: depends: libcrc32c,zstd_compress,zstd_decompress,raid6_pq,xor,zlib_deflate Signed-off-by: Nikolay Borisov <nborisov@suse.com> Reviewed-by: David Sterba <dsterba@suse.com> [ add more info to changelog from mails ] Signed-off-by: David Sterba <dsterba@suse.com> <