linux/fs/btrfs
Josef Bacik aec7db3b13 btrfs: fix setting last_trans for reloc roots
I made a mistake with my previous fix, I assumed that we didn't need to
mess with the reloc roots once we were out of the part of relocation where
we are actually moving the extents.

The subtle thing that I missed is that btrfs_init_reloc_root() also
updates the last_trans for the reloc root when we do
btrfs_record_root_in_trans() for the corresponding fs_root.  I've added a
comment to make sure future me doesn't make this mistake again.

This showed up as a WARN_ON() in btrfs_copy_root() because our
last_trans didn't == the current transid.  This could happen if we
snapshotted a fs root with a reloc root after we set
rc->create_reloc_tree = 0, but before we actually merge the reloc root.

Worth mentioning that the regression produced the following warning
when running snapshot creation and balance in parallel:

  BTRFS info (device sdc): relocating block group 30408704 flags metadata|dup
  ------------[ cut here ]------------
  WARNING: CPU: 0 PID: 12823 at fs/btrfs/ctree.c:191 btrfs_copy_root+0x26f/0x430 [btrfs]
  CPU: 0 PID: 12823 Comm: btrfs Tainted: G        W 5.6.0-rc7-btrfs-next-58 #1
  Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.12.0-59-gc9ba5276e321-prebuilt.qemu.org 04/01/2014
  RIP: 0010:btrfs_copy_root+0x26f/0x430 [btrfs]
  RSP: 0018:ffffb96e044279b8 EFLAGS: 00010202
  RAX: 0000000000000009 RBX: ffff9da70bf61000 RCX: ffffb96e04427a48
  RDX: ffff9da733a770c8 RSI: ffff9da70bf61000 RDI: ffff9da694163818
  RBP: ffff9da733a770c8 R08: fffffffffffffff8 R09: 0000000000000002
  R10: ffffb96e044279a0 R11: 0000000000000000 R12: ffff9da694163818
  R13: fffffffffffffff8 R14: ffff9da6d2512000 R15: ffff9da714cdac00
  FS:  00007fdeacf328c0(0000) GS:ffff9da735e00000(0000) knlGS:0000000000000000
  CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
  CR2: 000055a2a5b8a118 CR3: 00000001eed78002 CR4: 00000000003606f0
  DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
  DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
  Call Trace:
   ? create_reloc_root+0x49/0x2b0 [btrfs]
   ? kmem_cache_alloc_trace+0xe5/0x200
   create_reloc_root+0x8b/0x2b0 [btrfs]
   btrfs_reloc_post_snapshot+0x96/0x5b0 [btrfs]
   create_pending_snapshot+0x610/0x1010 [btrfs]
   create_pending_snapshots+0xa8/0xd0 [btrfs]
   btrfs_commit_transaction+0x4c7/0xc50 [btrfs]
   ? btrfs_mksubvol+0x3cd/0x560 [btrfs]
   btrfs_mksubvol+0x455/0x560 [btrfs]
   __btrfs_ioctl_snap_create+0x15f/0x190 [btrfs]
   btrfs_ioctl_snap_create_v2+0xa4/0xf0 [btrfs]
   ? mem_cgroup_commit_charge+0x6e/0x540
   btrfs_ioctl+0x12d8/0x3760 [btrfs]
   ? do_raw_spin_unlock+0x49/0xc0
   ? _raw_spin_unlock+0x29/0x40
   ? __handle_mm_fault+0x11b3/0x14b0
   ? ksys_ioctl+0x92/0xb0
   ksys_ioctl+0x92/0xb0
   ? trace_hardirqs_off_thunk+0x1a/0x1c
   __x64_sys_ioctl+0x16/0x20
   do_syscall_64+0x5c/0x280
   entry_SYSCALL_64_after_hwframe+0x49/0xbe
  RIP: 0033:0x7fdeabd3bdd7

Fixes: 2abc726ab4 ("btrfs: do not init a reloc root if we aren't relocating")
Reviewed-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2020-04-17 15:20:08 +02:00
..
tests btrfs: kill the subvol_srcu 2020-03-23 17:02:00 +01:00
acl.c btrfs: cleanup btrfs_setxattr_trans and drop transaction parameter 2019-04-29 19:02:44 +02:00
async-thread.c Btrfs: fix crash during unmount due to race with delayed inode workers 2020-03-23 17:01:51 +01:00
async-thread.h Btrfs: fix crash during unmount due to race with delayed inode workers 2020-03-23 17:01:51 +01:00
backref.c btrfs: do not resolve backrefs for roots that are being deleted 2020-03-23 17:03:51 +01:00
backref.h btrfs: relocation: Use btrfs_find_all_leafs to locate data extent parent tree leaves 2020-03-23 17:01:57 +01:00
block-group.c btrfs: fix reclaim counter leak of space_info objects 2020-04-08 19:11:19 +02:00
block-group.h btrfs: Move and unexport btrfs_rmap_block 2020-01-23 17:24:34 +01:00
block-rsv.c btrfs: Remove __ prefix from btrfs_block_rsv_release 2020-03-23 17:01:55 +01:00
block-rsv.h btrfs: Remove __ prefix from btrfs_block_rsv_release 2020-03-23 17:01:55 +01:00
btrfs_inode.h btrfs: introduce per-inode file extent tree 2020-03-23 17:01:24 +01:00
check-integrity.c btrfs: remove buffer_heads form super block mirror integrity checking 2020-03-23 17:01:40 +01:00
check-integrity.h btrfs: remove btrfsic_submit_bh() 2020-03-23 17:01:39 +01:00
compression.c btrfs: use larger zlib buffer for s390 hardware compression 2020-01-31 10:30:40 -08:00
compression.h btrfs: compression: remove ops pointer from workspace_manager 2019-11-18 12:46:59 +01:00
ctree.c btrfs: inline checksum name and driver definitions 2020-03-23 17:01:52 +01:00
ctree.h btrfs: kill the subvol_srcu 2020-03-23 17:02:00 +01:00
delalloc-space.c btrfs: Remove __ prefix from btrfs_block_rsv_release 2020-03-23 17:01:55 +01:00
delalloc-space.h btrfs: migrate the delalloc space stuff to it's own home 2019-07-04 17:26:17 +02:00
delayed-inode.c btrfs: use nofs allocations for running delayed items 2020-03-25 16:26:00 +01:00
delayed-inode.h btrfs: delayed-inode: Replace zero-length array with flexible-array member 2020-03-23 17:01:53 +01:00
delayed-ref.c btrfs: Remove __ prefix from btrfs_block_rsv_release 2020-03-23 17:01:55 +01:00
delayed-ref.h btrfs: migrate the delayed refs rsv code 2019-07-04 17:26:17 +02:00
dev-replace.c btrfs: sysfs, rename device_link add/remove functions 2020-03-23 17:01:35 +01:00
dev-replace.h btrfs: add __pure attribute to functions 2019-11-18 12:46:52 +01:00
dir-item.c btrfs: remove unused parameter fs_info from btrfs_extend_item 2019-04-29 19:02:50 +02:00
discard.c btrfs: add correction to handle -1 edge case in async discard 2020-01-20 16:41:01 +01:00
discard.h btrfs: have multiple discard lists 2020-01-20 16:41:00 +01:00
disk-io.c btrfs: kill the subvol_srcu 2020-03-23 17:02:00 +01:00
disk-io.h btrfs: move the root freeing stuff into btrfs_put_root 2020-03-23 17:01:59 +01:00
export.c btrfs: kill the subvol_srcu 2020-03-23 17:02:00 +01:00
export.h btrfs: export helpers for subvolume name/id resolution 2020-03-23 17:01:42 +01:00
extent_io.c btrfs: move the root freeing stuff into btrfs_put_root 2020-03-23 17:01:59 +01:00
extent_io.h btrfs: make the extent buffer leak check per fs info 2020-03-23 17:01:58 +01:00
extent_map.c Btrfs: fix race between using extent maps and merging them 2020-02-12 17:16:46 +01:00
extent_map.h btrfs: remove extent_map::bdev 2019-11-18 23:43:44 +01:00
extent-io-tree.h btrfs: switch to per-transaction pinned extents 2020-03-23 17:01:38 +01:00
extent-tree.c btrfs: do not use readahead for running delayed refs 2020-03-23 17:03:50 +01:00
file-item.c btrfs: add helper to get the end offset of a file extent item 2020-03-23 17:01:56 +01:00
file.c btrfs: make full fsyncs always operate on the entire file again 2020-04-08 19:10:52 +02:00
free-space-cache.c btrfs: simplify error handling in __btrfs_write_out_cache() 2020-03-23 17:01:43 +01:00
free-space-cache.h btrfs: have multiple discard lists 2020-01-20 16:41:00 +01:00
free-space-tree.c btrfs: move the root freeing stuff into btrfs_put_root 2020-03-23 17:01:59 +01:00
free-space-tree.h btrfs: rename btrfs_block_group_cache 2019-11-18 17:51:51 +01:00
inode-item.c btrfs: Make btrfs_find_name_in_ext_backref return struct btrfs_inode_extref 2019-09-09 14:59:16 +02:00
inode-map.c btrfs: Remove __ prefix from btrfs_block_rsv_release 2020-03-23 17:01:55 +01:00
inode-map.h
inode.c btrfs: kill the subvol_srcu 2020-03-23 17:02:00 +01:00
ioctl.c btrfs: Remove async_transid from btrfs_mksubvol/create_subvol/create_snapshot 2020-03-23 17:02:00 +01:00
Kconfig btrfs: add Kconfig dependency for BLAKE2B 2019-12-09 17:56:06 +01:00
locking.c btrfs: Implement DREW lock 2020-03-23 17:01:43 +01:00
locking.h btrfs: Implement DREW lock 2020-03-23 17:01:43 +01:00
lzo.c btrfs: compression: inline free_workspace 2019-11-18 12:46:59 +01:00
Makefile Btrfs: move all reflink implementation code into its own file 2020-03-23 17:01:54 +01:00
misc.h btrfs: add 64bit safe helper for power of two checks 2019-11-18 12:46:50 +01:00
ordered-data.c btrfs: drop argument tree from btrfs_lock_and_flush_ordered_range 2020-03-23 17:01:34 +01:00
ordered-data.h btrfs: drop argument tree from btrfs_lock_and_flush_ordered_range 2020-03-23 17:01:34 +01:00
orphan.c
print-tree.c btrfs: Remove unneeded semicolon 2020-01-20 16:40:55 +01:00
print-tree.h
props.c btrfs: Remove __ prefix from btrfs_block_rsv_release 2020-03-23 17:01:55 +01:00
props.h btrfs: delete unused function btrfs_set_prop_trans 2019-04-29 19:02:54 +02:00
qgroup.c btrfs: move the root freeing stuff into btrfs_put_root 2020-03-23 17:01:59 +01:00
qgroup.h btrfs: destroy qgroup extent records on transaction abort 2020-02-19 00:35:54 +01:00
raid56.c btrfs: use struct_size to calculate size of raid hash table 2020-03-23 17:01:44 +01:00
raid56.h btrfs: constify map parameter for nr_parity_stripes and nr_data_stripes 2019-07-01 13:34:58 +02:00
rcu-string.h btrfs: rcu-string: Replace zero-length array with flexible-array member 2020-03-23 17:01:53 +01:00
reada.c btrfs: rename btrfs_block_group_cache 2019-11-18 17:51:51 +01:00
ref-verify.c btrfs: fix ref-verify to catch operations on 0 ref extents 2020-03-23 17:01:56 +01:00
ref-verify.h btrfs: ref-verify: Use btrfs_ref to refactor btrfs_ref_tree_mod() 2019-04-29 19:02:49 +02:00
reflink.c btrfs: fix lost i_size update after cloning inline extent 2020-04-08 19:10:34 +02:00
reflink.h Btrfs: move all reflink implementation code into its own file 2020-03-23 17:01:54 +01:00
relocation.c btrfs: fix setting last_trans for reloc roots 2020-04-17 15:20:08 +02:00
root-tree.c btrfs: Remove __ prefix from btrfs_block_rsv_release 2020-03-23 17:01:55 +01:00
scrub.c btrfs: scrub: Replace zero-length array with flexible-array member 2020-03-23 17:01:54 +01:00
send.c btrfs: kill the subvol_srcu 2020-03-23 17:02:00 +01:00
send.h
space-info.c btrfs: fix reclaim counter leak of space_info objects 2020-04-08 19:11:19 +02:00
space-info.h btrfs: account ticket size at add/delete time 2020-03-23 17:01:55 +01:00
struct-funcs.c btrfs: tie extent buffer and it's token together 2019-09-09 14:59:16 +02:00
super.c btrfs: adjust message level for unrecognized mount option 2020-03-23 17:01:45 +01:00
sysfs.c btrfs: sysfs: Use scnprintf() instead of snprintf() 2020-03-23 18:14:47 +01:00
sysfs.h btrfs: sysfs, rename device_link add/remove functions 2020-03-23 17:01:35 +01:00
transaction.c btrfs: hold a ref on the root on the dead roots list 2020-03-23 17:01:59 +01:00
transaction.h btrfs: switch to per-transaction pinned extents 2020-03-23 17:01:38 +01:00
tree-checker.c btrfs: tree-checker: Verify location key for DIR_ITEM/DIR_INDEX 2020-01-20 16:40:56 +01:00
tree-checker.h btrfs: get fs_info from eb in btrfs_check_chunk_valid 2019-04-29 19:02:39 +02:00
tree-defrag.c
tree-log.c btrfs: make full fsyncs always operate on the entire file again 2020-04-08 19:10:52 +02:00
tree-log.h btrfs: get fs_info from trans in btrfs_set_log_full_commit 2019-04-29 19:02:41 +02:00
ulist.c
ulist.h
uuid-tree.c btrfs: bail out of uuid tree scanning if we're closing 2020-03-23 17:01:41 +01:00
volumes.c btrfs: relocation: add error injection points for cancelling balance 2020-03-23 17:01:54 +01:00
volumes.h btrfs: introduce chunk allocation policy 2020-03-23 17:01:48 +01:00
xattr.c Btrfs: fix failure to persist compression property xattr deletion on fsync 2019-06-17 16:37:17 +02:00
xattr.h btrfs: cleanup btrfs_setxattr_trans and drop transaction parameter 2019-04-29 19:02:44 +02:00
zlib.c btrfs: use larger zlib buffer for s390 hardware compression 2020-01-31 10:30:40 -08:00
zstd.c btrfs: compression: inline free_workspace 2019-11-18 12:46:59 +01:00