mirror_ubuntu-kernels/fs/btrfs
Qu Wenruo 0d27797e92 btrfs: make set/clear_extent_buffer_dirty() subpage compatible
For set_extent_buffer_dirty() to support subpage sized metadata, just
call btrfs_page_set_dirty() to handle both cases.

For clear_extent_buffer_dirty(), it needs to clear the page dirty if and
only if all extent buffers in the page range are no longer dirty.
Also do the same for page error.

This is pretty different from the existing clear_extent_buffer_dirty()
routine, so add a new helper function,
clear_subpage_extent_buffer_dirty() to do this for subpage metadata.

Also since the main part of clearing page dirty code is still the same,
extract that into btree_clear_page_dirty() so that it can be utilized
for both cases.

But there is a special race between set_extent_buffer_dirty() and
clear_extent_buffer_dirty(), where we can clear the page dirty.

[POSSIBLE RACE WINDOW]
For the race window between clear_subpage_extent_buffer_dirty() and
set_extent_buffer_dirty(), due to the fact that we can't call
clear_page_dirty_for_io() under subpage spin lock, we can race like
below:

   T1 (eb1 in the same page)	|  T2 (eb2 in the same page)
 -------------------------------+------------------------------
 set_extent_buffer_dirty()	| clear_extent_buffer_dirty()
 |- was_dirty = false;		| |- clear_subpagE_extent_buffer_dirty()
 |				|    |- btrfs_clear_and_test_dirty()
 |				|    |  Since eb2 is the last dirty page
 |				|    |  we got:
 |				|    |  last == true;
 |				|    |
 |- btrfs_page_set_dirty()	|    |
 |  We set the page dirty and   |    |
 |  subpage dirty bitmap	|    |
 |				|    |- if (last)
 |				|    |  Since we don't have subpage lock
 |				|    |  held, now @last is no longer
 |				|    |  correct
 |				|    |- btree_clear_page_dirty()
 |				|	Now PageDirty == false, even if
 |				|       we have dirty_bitmap not zero.
 |- ASSERT(PageDirty());	|
    ^^^^ CRASH

The solution here is to also lock the eb->pages[0] for subpage case of
set_extent_buffer_dirty(), to prevent racing with
clear_extent_buffer_dirty().

Signed-off-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2021-04-19 17:25:18 +02:00
..
tests idmapped-mounts-v5.12 2021-02-23 13:39:45 -08:00
acl.c fs: make helpers idmap mount aware 2021-01-24 14:27:20 +01:00
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: move the tree mod log code into its own file 2021-04-19 17:25:16 +02:00
backref.h btrfs: add asserts for deleting backref cache nodes 2021-02-08 22:58:56 +01:00
block-group.c btrfs: fix exhaustion of the system chunk array due to concurrent allocations 2021-04-19 17:25:17 +02:00
block-group.h btrfs: fix race between writes to swap files and scrub 2021-02-22 18:07:15 +01:00
block-rsv.c btrfs: introduce mount option rescue=ignorebadroots 2020-12-08 15:53:41 +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: remove stale comment and logic from btrfs_inode_in_log() 2021-04-19 17:25:16 +02:00
check-integrity.c btrfs: integrity-checker: convert block context kmap's to kmap_local_page 2021-04-19 17:25:16 +02:00
check-integrity.h btrfs: remove btrfsic_submit_bh() 2020-03-23 17:01:39 +01:00
compression.c btrfs: convert kmap to kmap_local_page, simple cases 2021-04-19 17:25:16 +02:00
compression.h btrfs: compression: move declarations to header 2020-10-07 12:06:55 +02:00
ctree.c btrfs: improve btree readahead for full send operations 2021-04-19 17:25:17 +02:00
ctree.h btrfs: improve btree readahead for full send operations 2021-04-19 17:25:17 +02:00
delalloc-space.c btrfs: fix parameter description of btrfs_inode_rsv_release/btrfs_delalloc_release_space 2021-02-08 22:58:54 +01:00
delalloc-space.h btrfs: make btrfs_delalloc_reserve_space take btrfs_inode 2020-07-27 12:55:36 +02:00
delayed-inode.c btrfs: use btrfs_inode_lock/btrfs_inode_unlock inode lock helpers 2021-04-19 17:25:15 +02:00
delayed-inode.h btrfs: make btrfs_delayed_update_inode take btrfs_inode 2020-12-08 15:54:10 +01:00
delayed-ref.c btrfs: update debug message when checking seq number of a delayed ref 2021-04-19 17:25:17 +02:00
delayed-ref.h btrfs: only let one thread pre-flush delayed refs in commit 2021-02-08 22:58:56 +01:00
dev-replace.c btrfs: do not initialize dev replace for bad dev root 2021-03-17 19:42:14 +01:00
dev-replace.h btrfs: zoned: mark block groups to copy for device-replace 2021-02-09 02:46:07 +01:00
dir-item.c btrfs: locking: rip out path->leave_spinning 2020-12-08 15:54:02 +01:00
discard.c btrfs: document now parameter of peek_discard_list 2021-02-08 22:58:53 +01:00
discard.h btrfs: cleanup btrfs_discard_update_discardable usage 2020-12-08 15:54:02 +01:00
disk-io.c btrfs: subpage: support metadata checksum calculation at write time 2021-04-19 17:25:18 +02:00
disk-io.h btrfs: split alloc_log_tree() 2021-02-09 02:46:07 +01:00
export.c btrfs: locking: rip out path->leave_spinning 2020-12-08 15:54:02 +01:00
export.h btrfs: export helpers for subvolume name/id resolution 2020-03-23 17:01:42 +01:00
extent_io.c btrfs: make set/clear_extent_buffer_dirty() subpage compatible 2021-04-19 17:25:18 +02:00
extent_io.h btrfs: zoned: redirty released extent buffers 2021-02-09 02:46:04 +01:00
extent_map.c btrfs: fix parameter description of btrfs_add_extent_mapping 2021-02-08 22:58:53 +01:00
extent_map.h btrfs: remove extent_map::bdev 2019-11-18 23:43:44 +01:00
extent-io-tree.h btrfs: use fixed width int type for extent_state::state 2020-12-08 15:54:13 +01:00
extent-tree.c btrfs: use the new bit BTRFS_FS_TREE_MOD_LOG_USERS at btrfs_free_tree_block() 2021-04-19 17:25:16 +02:00
file-item.c btrfs: remove duplicated in_range() macro 2021-04-19 17:25:16 +02:00
file.c btrfs: fix a potential hole punching failure 2021-04-19 17:25:17 +02:00
free-space-cache.c btrfs: zoned: do not account freed region of read-only block group as zone_unusable 2021-03-04 16:16:58 +01:00
free-space-cache.h btrfs: zoned: track unusable bytes for zones 2021-02-09 02:46:03 +01:00
free-space-tree.c btrfs: fix possible free space tree corruption with online conversion 2021-01-25 18:44:37 +01:00
free-space-tree.h btrfs: rename btrfs_block_group_cache 2019-11-18 17:51:51 +01:00
inode-item.c btrfs: locking: rip out path->leave_spinning 2020-12-08 15:54:02 +01:00
inode.c btrfs: remove unnecessary variable shadowing in btrfs_invalidatepage() 2021-04-19 17:25:18 +02:00
ioctl.c btrfs: use btrfs_inode_lock/btrfs_inode_unlock inode lock helpers 2021-04-19 17:25:15 +02:00
Kconfig btrfs: switch to iomap for direct IO 2020-10-07 12:06:57 +02:00
locking.c btrfs: remove the recurse parameter from __btrfs_tree_read_lock 2020-12-08 15:54:09 +01:00
locking.h btrfs: remove the recurse parameter from __btrfs_tree_read_lock 2020-12-08 15:54:09 +01:00
lzo.c btrfs: convert kmap to kmap_local_page, simple cases 2021-04-19 17:25:16 +02:00
Makefile btrfs: move the tree mod log code into its own file 2021-04-19 17:25:16 +02:00
misc.h btrfs: rename tree_entry to rb_simple_node and export it 2020-05-25 11:25:19 +02:00
ordered-data.c btrfs: replace offset_in_entry with in_range 2021-04-19 17:25:14 +02:00
ordered-data.h btrfs: fix comment for btrfs ordered extent flag bits 2021-04-19 17:25:14 +02:00
orphan.c
print-tree.c btrfs: print the actual offset in btrfs_root_name 2021-01-07 17:25:05 +01:00
print-tree.h btrfs: print the actual offset in btrfs_root_name 2021-01-07 17:25:05 +01:00
props.c btrfs: simplify iget helpers 2020-05-25 11:25:37 +02:00
props.h
qgroup.c btrfs: move the tree mod log code into its own file 2021-04-19 17:25:16 +02:00
qgroup.h btrfs: export and rename qgroup_reserve_meta 2021-03-02 16:58:30 +01:00
raid56.c btrfs: raid56: convert kmaps to kmap_local_page 2021-04-19 17:25:16 +02:00
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: subpage: make readahead work properly 2021-03-16 11:06:21 +01:00
ref-verify.c btrfs: ref-verify: use 'inline void' keyword ordering 2021-03-02 16:55:40 +01:00
ref-verify.h
reflink.c btrfs: make reflinks respect O_SYNC O_DSYNC and S_SYNC flags 2021-04-19 17:25:17 +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: use btrfs_inode_lock/btrfs_inode_unlock inode lock helpers 2021-04-19 17:25:15 +02:00
root-tree.c btrfs: qgroup: fix qgroup meta rsv leak for subvolume operations 2020-10-07 12:12:13 +02:00
scrub.c btrfs: scrub: drop a few function declarations 2021-04-19 17:25:14 +02:00
send.c btrfs: improve btree readahead for full send operations 2021-04-19 17:25:17 +02:00
send.h btrfs: send: avoid copying file data 2020-10-07 12:13:17 +02:00
space-info.c btrfs: use percpu_read_positive instead of sum_positive for need_preempt 2021-04-19 17:25:17 +02:00
space-info.h btrfs: zoned: track unusable bytes for zones 2021-02-09 02:46:03 +01:00
struct-funcs.c btrfs: handle sectorsize < PAGE_SIZE case for extent buffer accessors 2020-12-09 19:16:10 +01:00
subpage.c btrfs: subpage: introduce helpers for writeback status 2021-04-19 17:25:18 +02:00
subpage.h btrfs: subpage: introduce helpers for writeback status 2021-04-19 17:25:18 +02:00
super.c btrfs: fix spurious free_space_tree remount warning 2021-03-02 16:55:55 +01:00
sysfs.c btrfs: add sysfs interface for supported sectorsize 2021-04-19 17:25:18 +02:00
sysfs.h btrfs: split and refactor btrfs_sysfs_remove_devices_dir 2020-10-07 12:12:21 +02:00
transaction.c btrfs: fix exhaustion of the system chunk array due to concurrent allocations 2021-04-19 17:25:17 +02:00
transaction.h btrfs: fix exhaustion of the system chunk array due to concurrent allocations 2021-04-19 17:25:17 +02:00
tree-checker.c btrfs: tree-checker: do not error out if extent ref hash doesn't match 2021-02-22 18:07:44 +01:00
tree-checker.h
tree-defrag.c btrfs: locking: remove all the blocking helpers 2020-12-08 15:54:01 +01:00
tree-log.c btrfs: zoned: move log tree node allocation out of log_root_tree->log_mutex 2021-04-19 17:25:17 +02:00
tree-log.h btrfs: make fast fsyncs wait only for writeback 2020-10-07 12:06:56 +02:00
tree-mod-log.c btrfs: add and use helper to get lowest sequence number for the tree mod log 2021-04-19 17:25:17 +02:00
tree-mod-log.h btrfs: add and use helper to get lowest sequence number for the tree mod log 2021-04-19 17:25:17 +02:00
ulist.c
ulist.h
uuid-tree.c btrfs: remove unnecessary casts in printk 2020-12-08 15:53:52 +01:00
volumes.c btrfs: zoned: bail out in btrfs_alloc_chunk for bad input 2021-04-19 17:25:17 +02:00
volumes.h btrfs: zoned: relocate block group to repair IO failure in zoned filesystems 2021-02-09 02:46:07 +01:00
xattr.c for-5.12-rc1-tag 2021-03-05 12:21:14 -08:00
xattr.h
zlib.c btrfs: use memcpy_[to|from]_page() and kmap_local_page() 2021-02-26 12:45:15 +01:00
zoned.c for-5.12-rc6-tag 2021-04-11 11:53:36 -07:00
zoned.h btrfs: zoned: extend zoned allocator to use dedicated tree-log block group 2021-02-09 02:46:08 +01:00
zstd.c btrfs: use memcpy_[to|from]_page() and kmap_local_page() 2021-02-26 12:45:15 +01:00