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2018-11-11Merge tag 'for-4.20-rc1-tag' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux Pull btrfs fixes from David Sterba: "Several fixes to recent release (4.19, fixes tagged for stable) and other fixes" * tag 'for-4.20-rc1-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux: Btrfs: fix missing delayed iputs on unmount Btrfs: fix data corruption due to cloning of eof block Btrfs: fix infinite loop on inode eviction after deduplication of eof block Btrfs: fix deadlock on tree root leaf when finding free extent btrfs: avoid link error with CONFIG_NO_AUTO_INLINE btrfs: tree-checker: Fix misleading group system information Btrfs: fix missing data checksums after a ranged fsync (msync) btrfs: fix pinned underflow after transaction aborted Btrfs: fix cur_offset in the error case for nocow
2018-11-06Btrfs: fix deadlock on tree root leaf when finding free extentFilipe Manana
When we are writing out a free space cache, during the transaction commit phase, we can end up in a deadlock which results in a stack trace like the following: schedule+0x28/0x80 btrfs_tree_read_lock+0x8e/0x120 [btrfs] ? finish_wait+0x80/0x80 btrfs_read_lock_root_node+0x2f/0x40 [btrfs] btrfs_search_slot+0xf6/0x9f0 [btrfs] ? evict_refill_and_join+0xd0/0xd0 [btrfs] ? inode_insert5+0x119/0x190 btrfs_lookup_inode+0x3a/0xc0 [btrfs] ? kmem_cache_alloc+0x166/0x1d0 btrfs_iget+0x113/0x690 [btrfs] __lookup_free_space_inode+0xd8/0x150 [btrfs] lookup_free_space_inode+0x5b/0xb0 [btrfs] load_free_space_cache+0x7c/0x170 [btrfs] ? cache_block_group+0x72/0x3b0 [btrfs] cache_block_group+0x1b3/0x3b0 [btrfs] ? finish_wait+0x80/0x80 find_free_extent+0x799/0x1010 [btrfs] btrfs_reserve_extent+0x9b/0x180 [btrfs] btrfs_alloc_tree_block+0x1b3/0x4f0 [btrfs] __btrfs_cow_block+0x11d/0x500 [btrfs] btrfs_cow_block+0xdc/0x180 [btrfs] btrfs_search_slot+0x3bd/0x9f0 [btrfs] btrfs_lookup_inode+0x3a/0xc0 [btrfs] ? kmem_cache_alloc+0x166/0x1d0 btrfs_update_inode_item+0x46/0x100 [btrfs] cache_save_setup+0xe4/0x3a0 [btrfs] btrfs_start_dirty_block_groups+0x1be/0x480 [btrfs] btrfs_commit_transaction+0xcb/0x8b0 [btrfs] At cache_save_setup() we need to update the inode item of a block group's cache which is located in the tree root (fs_info->tree_root), which means that it may result in COWing a leaf from that tree. If that happens we need to find a free metadata extent and while looking for one, if we find a block group which was not cached yet we attempt to load its cache by calling cache_block_group(). However this function will try to load the inode of the free space cache, which requires finding the matching inode item in the tree root - if that inode item is located in the same leaf as the inode item of the space cache we are updating at cache_save_setup(), we end up in a deadlock, since we try to obtain a read lock on the same extent buffer that we previously write locked. So fix this by using the tree root's commit root when searching for a block group's free space cache inode item when we are attempting to load a free space cache. This is safe since block groups once loaded stay in memory forever, as well as their caches, so after they are first loaded we will never need to read their inode items again. For new block groups, once they are created they get their ->cached field set to BTRFS_CACHE_FINISHED meaning we will not need to read their inode item. Reported-by: Andrew Nelson <andrew.s.nelson@gmail.com> Link: https://lore.kernel.org/linux-btrfs/CAPTELenq9x5KOWuQ+fa7h1r3nsJG8vyiTH8+ifjURc_duHh2Wg@mail.gmail.com/ Fixes: 9d66e233c704 ("Btrfs: load free space cache if it exists") Tested-by: Andrew Nelson <andrew.s.nelson@gmail.com> Reviewed-by: Josef Bacik <josef@toxicpanda.com> Signed-off-by: Filipe Manana <fdmanana@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2018-11-06Btrfs: fix cur_offset in the error case for nocowRobbie Ko
When the cow_file_range fails, the related resources are unlocked according to the range [start..end), so the unlock cannot be repeated in run_delalloc_nocow. In some cases (e.g. cur_offset <= end && cow_start != -1), cur_offset is not updated correctly, so move the cur_offset update before cow_file_range. kernel BUG at mm/page-writeback.c:2663! Internal error: Oops - BUG: 0 [#1] SMP CPU: 3 PID: 31525 Comm: kworker/u8:7 Tainted: P O Hardware name: Realtek_RTD1296 (DT) Workqueue: writeback wb_workfn (flush-btrfs-1) task: ffffffc076db3380 ti: ffffffc02e9ac000 task.ti: ffffffc02e9ac000 PC is at clear_page_dirty_for_io+0x1bc/0x1e8 LR is at clear_page_dirty_for_io+0x14/0x1e8 pc : [<ffffffc00033c91c>] lr : [<ffffffc00033c774>] pstate: 40000145 sp : ffffffc02e9af4f0 Process kworker/u8:7 (pid: 31525, stack limit = 0xffffffc02e9ac020) Call trace: [<ffffffc00033c91c>] clear_page_dirty_for_io+0x1bc/0x1e8 [<ffffffbffc514674>] extent_clear_unlock_delalloc+0x1e4/0x210 [btrfs] [<ffffffbffc4fb168>] run_delalloc_nocow+0x3b8/0x948 [btrfs] [<ffffffbffc4fb948>] run_delalloc_range+0x250/0x3a8 [btrfs] [<ffffffbffc514c0c>] writepage_delalloc.isra.21+0xbc/0x1d8 [btrfs] [<ffffffbffc516048>] __extent_writepage+0xe8/0x248 [btrfs] [<ffffffbffc51630c>] extent_write_cache_pages.isra.17+0x164/0x378 [btrfs] [<ffffffbffc5185a8>] extent_writepages+0x48/0x68 [btrfs] [<ffffffbffc4f5828>] btrfs_writepages+0x20/0x30 [btrfs] [<ffffffc00033d758>] do_writepages+0x30/0x88 [<ffffffc0003ba0f4>] __writeback_single_inode+0x34/0x198 [<ffffffc0003ba6c4>] writeback_sb_inodes+0x184/0x3c0 [<ffffffc0003ba96c>] __writeback_inodes_wb+0x6c/0xc0 [<ffffffc0003bac20>] wb_writeback+0x1b8/0x1c0 [<ffffffc0003bb0f0>] wb_workfn+0x150/0x250 [<ffffffc0002b0014>] process_one_work+0x1dc/0x388 [<ffffffc0002b02f0>] worker_thread+0x130/0x500 [<ffffffc0002b6344>] kthread+0x10c/0x110 [<ffffffc000284590>] ret_from_fork+0x10/0x40 Code: d503201f a9025bb5 a90363b7 f90023b9 (d4210000) CC: stable@vger.kernel.org # 4.4+ Reviewed-by: Filipe Manana <fdmanana@suse.com> Signed-off-by: Robbie Ko <robbieko@synology.com> Signed-off-by: David Sterba <dsterba@suse.com>
2018-10-30Merge tag 'for-4.20-part2-tag' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux Pull more btrfs updates from David Sterba: "This contains a few minor updates and fixes that were under testing or arrived shortly after the merge window freeze, mostly stable material" * tag 'for-4.20-part2-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux: Btrfs: fix use-after-free when dumping free space Btrfs: fix use-after-free during inode eviction btrfs: move the dio_sem higher up the callchain btrfs: don't run delayed_iputs in commit btrfs: fix insert_reserved error handling btrfs: only free reserved extent if we didn't insert it btrfs: don't use ctl->free_space for max_extent_size btrfs: set max_extent_size properly btrfs: reset max_extent_size properly MAINTAINERS: update my email address for btrfs btrfs: delayed-ref: extract find_first_ref_head from find_ref_head Btrfs: fix deadlock when writing out free space caches Btrfs: fix assertion on fsync of regular file when using no-holes feature Btrfs: fix null pointer dereference on compressed write path error
2018-10-25Merge branch 'work.lookup' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs Pull more ->lookup() cleanups from Al Viro: "Some ->lookup() instances are still overcomplicating the life for themselves, open-coding the stuff that would be handled by d_splice_alias() just fine. Simplify a couple of such cases caught this cycle and document d_splice_alias() intended use" * 'work.lookup' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: Document d_splice_alias() calling conventions for ->lookup() users. simplify btrfs_lookup() clean erofs_lookup()
2018-10-19Btrfs: fix use-after-free during inode evictionFilipe Manana
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 6ca0709756710 ("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: b9d0b38928e2 ("btrfs: Add handler for invalidate page") CC: stable@vger.kernel.org # 4.4+ Reviewed-by: Qu Wenruo <wqu@suse.com> Signed-off-by: Filipe Manana <fdmanana@suse.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2018-10-19btrfs: only free reserved extent if we didn't insert itJosef Bacik
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: 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 null pointer dereference on compressed write path errorFilipe Manana
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: 771ed689d2cd ("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: Filipe Manana <fdmanana@suse.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2018-10-15btrfs: remove fs_info from btrfs_should_throttle_delayed_refsLu Fengqi
The avg_delayed_ref_runtime can be referenced from the transaction handle. Signed-off-by: Lu Fengqi <lufq.fnst@cn.fujitsu.com> Reviewed-by: Nikolay Borisov <nborisov@suse.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2018-10-15btrfs: remove fs_info from btrfs_check_space_for_delayed_refsLu Fengqi
It can be referenced from the transaction handle. Signed-off-by: Lu Fengqi <lufq.fnst@cn.fujitsu.com> Reviewed-by: Nikolay Borisov <nborisov@suse.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2018-10-15btrfs: drop min_size from evict_refill_and_joinJosef Bacik
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: Josef Bacik <josef@toxicpanda.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2018-10-15Btrfs: get rid of btrfs_symlink_aopsOmar Sandoval
The only aops we define for symlinks are identical to the aops for regular files. This has been the case since symlink support was added in commit 2b8d99a723a3 ("Btrfs: symlinks and hard links"). As far as I can tell, there wasn't a good reason to have separate aops then, and there isn't now, so let's just do what most other filesystems do and reuse the same structure. Signed-off-by: Omar Sandoval <osandov@fb.com> Reviewed-by: Nikolay Borisov <nborisov@suse.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2018-10-15Btrfs: extent_map: use rb_first_cachedLiu Bo
rb_first_cached() trades an extra pointer "leftmost" for doing the same job as rb_first() but in O(1). As evict_inode_truncate_pages() removes all extent mapping by always looking for the first rb entry, it's helpful to use rb_first_cached instead. For more details about the optimization see patch "Btrfs: delayed-refs: use rb_first_cached for href_root". Tested-by: Holger Hoffstätte <holger@applied-asynchrony.com> Signed-off-by: Liu Bo <bo.liu@linux.alibaba.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2018-10-15btrfs: Remove logically dead code from btrfs_orphan_cleanupNikolay Borisov
In btrfs_orphan_cleanup the final 'if (ret) goto out' cannot ever be executed. This is due to the last assignment to 'ret' depending on the return value of btrfs_iget. If an error other than -ENOENT is returned then the loop is prematurely terminated by 'goto out'. On the other hand, if the error value is ENOENT then a subsequent if branch is executed that always re-assigns 'ret' and in case it's an error just terminates the loop. No functional changes. Coverity-id: 1437392 Signed-off-by: Nikolay Borisov <nborisov@suse.com> Reviewed-by: Lu Fengqi <lufq.fnst@cn.fujitsu.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2018-10-15Btrfs: remove wait_ordered_range in btrfs_evict_inodeLiu Bo
When we delete an inode, btrfs_evict_inode() { truncate_inode_pages_final() truncate_inode_pages_range() lock_page() truncate_cleanup_page() btrfs_invalidatepage() wait_on_page_writeback btrfs_lookup_ordered_range() cancel_dirty_page() unlock_page() ... btrfs_wait_ordered_range() ... As VFS has called ->invalidatepage() to get all ordered extents done (if there are any) and truncated all page cache pages (no dirty pages to writeback after this step), wait_ordered_range() is just a noop. Signed-off-by: Liu Bo <bo.liu@linux.alibaba.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2018-10-15Btrfs: unify error handling of btrfs_lookup_dir_itemLiu Bo
Unify the error handling of directory item lookups using IS_ERR_OR_NULL. No functional changes. Signed-off-by: Liu Bo <bo.liu@linux.alibaba.com> Reviewed-by: Nikolay Borisov <nborisov@suse.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2018-10-15Btrfs: set leave_spinning in btrfs_get_extentLiu Bo
Unless it's going to read inline extents from btree leaf to page, btrfs_get_extent won't sleep during the period of holding path lock. This sets leave_spinning at first and sets path to blocking mode right before reading inline extent if that's the case. The benefit is that a path in spinning mode typically has lower impact (faster) on waiters rather than that in the blocking mode. Signed-off-by: Liu Bo <bo.liu@linux.alibaba.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2018-10-15Btrfs: fix alignment in declaration and prototype of btrfs_get_extentLiu Bo
This fixes btrfs_get_extent to be consistent with our existing declaration style. Note: For the record, indentation styles that are accepted are both, aligning under the opening ( and tab or double tab indentation on the next line. Preferrably not spliting the type or long expressions in the argument lists. Signed-off-by: Liu Bo <bo.liu@linux.alibaba.com> [ add note ] Signed-off-by: David Sterba <dsterba@suse.com>
2018-10-15btrfs: remove unused pointer inode in relink_file_extentsColin Ian King
Pointer inode is being assigned but is never used hence it is redundant and can be removed. It's been unused since the introduction in 38c227d87c49a ("Btrfs: snapshot-aware defrag"). Cleans up clang warning: variable ‘inode’ set but not used [-Wunused-but-set-variable] Signed-off-by: Colin Ian King <colin.king@canonical.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2018-10-15btrfs: free path at an earlier point in btrfs_get_extentLiu Bo
trace_btrfs_get_extent() has nothing to do with path, place btrfs_free_path ahead so that we can unlock path on error. Signed-off-by: Liu Bo <bo.liu@linux.alibaba.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2018-10-15Btrfs: remove always true if branch in btrfs_get_extentLiu Bo
@path is always NULL when it comes to the if branch. Signed-off-by: Liu Bo <bo.liu@linux.alibaba.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2018-10-15btrfs: Remove 'objectid' member from struct btrfs_rootMisono Tomohiro
There are two members in struct btrfs_root which indicate root's objectid: objectid and root_key.objectid. They are both set to the same value in __setup_root(): static void __setup_root(struct btrfs_root *root, struct btrfs_fs_info *fs_info, u64 objectid) { ... root->objectid = objectid; ... root->root_key.objectid = objecitd; ... } and not changed to other value after initialization. grep in btrfs directory shows both are used in many places: $ grep -rI "root->root_key.objectid" | wc -l 133 $ grep -rI "root->objectid" | wc -l 55 (4.17, inc. some noise) It is confusing to have two similar variable names and it seems that there is no rule about which should be used in a certain case. Since ->root_key itself is needed for tree reloc tree, let's remove 'objecitd' member and unify code to use ->root_key.objectid in all places. Signed-off-by: Misono Tomohiro <misono.tomohiro@jp.fujitsu.com> Reviewed-by: Qu Wenruo <wqu@suse.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2018-10-15btrfs: Remove root parameter from btrfs_insert_dir_itemLu Fengqi
All callers pass the root tree of dir, we can push that down to the function itself. 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>
2018-10-15btrfs: switch update_size to bool in btrfs_block_rsv_migrate and ↵Lu Fengqi
btrfs_rsv_add_bytes Using true and false here is closer to the expected semantic than using 0 and 1. No functional change. 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>
2018-10-15btrfs: simplify the send_in_progress check in btrfs_delete_subvolumeLu Fengqi
Only when send_in_progress, we have to do something different such as btrfs_warn() and return -EPERM. Therefore, we could check send_in_progress first and process error handling, after the root_item_lock has been got. Just for better readability. No functional change. 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>
2018-10-10simplify btrfs_lookup()Al Viro
d_splice_alias() is fine with ERR_PTR(-E...) for inode Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2018-09-06Merge tag 'for-4.19-rc2-tag' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux Pull btrfs fixes from David Sterba: - fix for improper fsync after hardlink - fix for a corruption during file deduplication - use after free fixes - RCU warning fix - fix for buffered write to nodatacow file * tag 'for-4.19-rc2-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux: btrfs: Fix suspicious RCU usage warning in btrfs_debug_in_rcu btrfs: use after free in btrfs_quota_enable btrfs: btrfs_shrink_device should call commit transaction at the end btrfs: fix qgroup_free wrong num_bytes in btrfs_subvolume_reserve_metadata Btrfs: fix data corruption when deduplicating between different files Btrfs: sync log after logging new name Btrfs: fix unexpected failure of nocow buffered writes after snapshotting when low on space
2018-08-23Btrfs: sync log after logging new nameFilipe Manana
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>
2018-08-17Btrfs: fix unexpected failure of nocow buffered writes after snapshotting ↵Robbie Ko
when low on space Commit e9894fd3e3b3 ("Btrfs: fix snapshot vs nocow writting") forced nocow writes to fallback to COW, during writeback, when a snapshot is created. This resulted in writes made before creating the snapshot to unexpectedly fail with ENOSPC during writeback when success (0) was returned to user space through the write system call. The steps leading to this problem are: 1. When it's not possible to allocate data space for a write, the buffered write path checks if a NOCOW write is possible. If it is, it will not reserve space and success (0) is returned to user space. 2. Then when a snapshot is created, the root's will_be_snapshotted atomic is incremented and writeback is triggered for all inode's that belong to the root being snapshotted. Incrementing that atomic forces all previous writes to fallback to COW during writeback (running delalloc). 3. This results in the writeback for the inodes to fail and therefore setting the ENOSPC error in their mappings, so that a subsequent fsync on them will report the error to user space. So it's not a completely silent data loss (since fsync will report ENOSPC) but it's a very unexpected and undesirable behaviour, because if a clean shutdown/unmount of the filesystem happens without previous calls to fsync, it is expected to have the data present in the files after mounting the filesystem again. So fix this by adding a new atomic named snapshot_force_cow to the root structure which prevents this behaviour and works the following way: 1. It is incremented when we start to create a snapshot after triggering writeback and before waiting for writeback to finish. 2. This new atomic is now what is used by writeback (running delalloc) to decide whether we need to fallback to COW or not. Because we incremented this new atomic after triggering writeback in the snapshot creation ioctl, we ensure that all buffered writes that happened before snapshot creation will succeed and not fallback to COW (which would make them fail with ENOSPC). 3. The existing atomic, will_be_snapshotted, is kept because it is used to force new buffered writes, that start after we started snapshotting, to reserve data space even when NOCOW is possible. This makes these writes fail early with ENOSPC when there's no available space to allocate, preventing the unexpected behaviour of writeback later failing with ENOSPC due to a fallback to COW mode. Fixes: e9894fd3e3b3 ("Btrfs: fix snapshot vs nocow writting") Signed-off-by: Robbie Ko <robbieko@synology.com> Reviewed-by: Filipe Manana <fdmanana@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2018-08-13Merge tag 'for-4.19-tag' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux Pull btrfs updates from David Sterba: "Mostly fixes and cleanups, nothing big, though the notable thing is the inserted/deleted lines delta -1124. User visible changes: - allow defrag on opened read-only files that have rw permissions; similar to what dedupe will allow on such files Core changes: - tree checker improvements, reported by fuzzing: * more checks for: block group items, essential trees * chunk type validation * mount time cross-checks that physical and logical chunks match * switch more error codes to EUCLEAN aka EFSCORRUPTED Fixes: - fsync corner case fixes - fix send failure when root has deleted files still open - send, fix incorrect file layout after hole punching beyond eof - fix races between mount and deice scan ioctl, found by fuzzing - fix deadlock when delayed iput is called from writeback on the same inode; rare but has been observed in practice, also removes code - fix pinned byte accounting, using the right percpu helpers; this should avoid some write IO inefficiency during low space conditions - don't remove block group that still has pinned bytes - reset on-disk device stats value after replace, otherwise this would report stale values for the new device Cleanups: - time64_t/timespec64 cleanups - remove remaining dead code in scrub handling NOCOW extents after disabling it in previous cycle - simplify fsync regarding ordered extents logic and remove all the related code - remove redundant arguments in order to reduce stack space consumption - remove support for V0 type of extents, not in use since 2.6.30 - remove several unused structure members - fewer indirect function calls by inlining some callbacks - qgroup rescan timing fixes - vfs: iget cleanups" * tag 'for-4.19-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux: (182 commits) btrfs: revert fs_devices state on error of btrfs_init_new_device btrfs: Exit gracefully when chunk map cannot be inserted to the tree btrfs: Introduce mount time chunk <-> dev extent mapping check btrfs: Verify that every chunk has corresponding block group at mount time btrfs: Check that each block group has corresponding chunk at mount time Btrfs: send, fix incorrect file layout after hole punching beyond eof btrfs: Use wrapper macro for rcu string to remove duplicate code btrfs: simplify btrfs_iget btrfs: lift make_bad_inode into btrfs_iget btrfs: simplify IS_ERR/PTR_ERR checks btrfs: btrfs_iget never returns an is_bad_inode inode btrfs: replace: Reset on-disk dev stats value after replace btrfs: extent-tree: Remove unused __btrfs_free_block_rsv btrfs: backref: Use ERR_CAST to return error code btrfs: Remove redundant btrfs_release_path from btrfs_unlink_subvol btrfs: Remove root parameter from btrfs_unlink_subvol btrfs: Remove fs_info from btrfs_add_root_ref btrfs: Remove fs_info from btrfs_del_root_ref btrfs: Remove fs_info from btrfs_del_root btrfs: Remove fs_info from btrfs_delete_delayed_dir_index ...
2018-08-13Merge branch 'work.mkdir' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs Pull vfs icache updates from Al Viro: - NFS mkdir/open_by_handle race fix - analogous solution for FUSE, replacing the one currently in mainline - new primitive to be used when discarding halfway set up inodes on failed object creation; gives sane warranties re icache lookups not returning such doomed by still not freed inodes. A bunch of filesystems switched to that animal. - Miklos' fix for last cycle regression in iget5_locked(); -stable will need a slightly different variant, unfortunately. - misc bits and pieces around things icache-related (in adfs and jfs). * 'work.mkdir' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: jfs: don't bother with make_bad_inode() in ialloc() adfs: don't put inodes into icache new helper: inode_fake_hash() vfs: don't evict uninitialized inode jfs: switch to discard_new_inode() ext2: make sure that partially set up inodes won't be returned by ext2_iget() udf: switch to discard_new_inode() ufs: switch to discard_new_inode() btrfs: switch to discard_new_inode() new primitive: discard_new_inode() kill d_instantiate_no_diralias() nfs_instantiate(): prevent multiple aliases for directory inode
2018-08-06btrfs: simplify btrfs_igetAl Viro
Don't open-code iget_failed(), don't bother with btrfs_free_path(NULL), move handling of positive return values of btrfs_lookup_inode() from btrfs_read_locked_inode() to btrfs_iget() and kill now obviously pointless ASSERT() in there. 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: lift make_bad_inode into btrfs_igetAl Viro
We don't need to check is_bad_inode() after the call of btrfs_read_locked_inode() - it's exactly the same as checking return value for being non-zero. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Reviewed-by: David Sterba <dsterba@suse.com> Reviewed-by: Nikolay Borisov <nborisov@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2018-08-06btrfs: Remove redundant btrfs_release_path from btrfs_unlink_subvolLu Fengqi
Although it is safe to call this on already released paths with no locks held or extent buffers, removing the redundant btrfs_release_path is reasonable. 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: Remove root parameter from btrfs_unlink_subvolLu Fengqi
All callers pass the root tree of dir, we can push that down to the function itself. 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: Remove fs_info from btrfs_add_root_refLu Fengqi
It can be referenced from the passed transaction handle. Signed-off-by: Lu Fengqi <lufq.fnst@cn.fujitsu.com> Signed-off-by: David Sterba <dsterba@suse.com>
2018-08-06btrfs: Remove fs_info from btrfs_del_root_refLu Fengqi
It can be referenced from the passed transaction handle. Signed-off-by: Lu Fengqi <lufq.fnst@cn.fujitsu.com> Signed-off-by: David Sterba <dsterba@suse.com>
2018-08-06btrfs: Remove fs_info from btrfs_delete_delayed_dir_indexLu Fengqi
It can be referenced from the passed transaction handle. Signed-off-by: Lu Fengqi <lufq.fnst@cn.fujitsu.com> Signed-off-by: David Sterba <dsterba@suse.com>
2018-08-06Btrfs: fix btrfs_write_inode vs delayed iput deadlockJosef Bacik
We recently ran into the following deadlock involving btrfs_write_inode(): [ +0.005066] __schedule+0x38e/0x8c0 [ +0.007144] schedule+0x36/0x80 [ +0.006447] bit_wait+0x11/0x60 [ +0.006446] __wait_on_bit+0xbe/0x110 [ +0.007487] ? bit_wait_io+0x60/0x60 [ +0.007319] __inode_wait_for_writeback+0x96/0xc0 [ +0.009568] ? autoremove_wake_function+0x40/0x40 [ +0.009565] inode_wait_for_writeback+0x21/0x30 [ +0.009224] evict+0xb0/0x190 [ +0.006099] iput+0x1a8/0x210 [ +0.006103] btrfs_run_delayed_iputs+0x73/0xc0 [ +0.009047] btrfs_commit_transaction+0x799/0x8c0 [ +0.009567] btrfs_write_inode+0x81/0xb0 [ +0.008008] __writeback_single_inode+0x267/0x320 [ +0.009569] writeback_sb_inodes+0x25b/0x4e0 [ +0.008702] wb_writeback+0x102/0x2d0 [ +0.007487] wb_workfn+0xa4/0x310 [ +0.006794] ? wb_workfn+0xa4/0x310 [ +0.007143] process_one_work+0x150/0x410 [ +0.008179] worker_thread+0x6d/0x520 [ +0.007490] kthread+0x12c/0x160 [ +0.006620] ? put_pwq_unlocked+0x80/0x80 [ +0.008185] ? kthread_park+0xa0/0xa0 [ +0.007484] ? do_syscall_64+0x53/0x150 [ +0.007837] ret_from_fork+0x29/0x40 Writeback calls: btrfs_write_inode btrfs_commit_transaction btrfs_run_delayed_iputs If iput() is called on that same inode, evict() will wait for writeback forever. btrfs_write_inode() was originally added way back in 4730a4bc5bf3 ("btrfs_dirty_inode") to support O_SYNC writes. However, ->write_inode() hasn't been used for O_SYNC since 148f948ba877 ("vfs: Introduce new helpers for syncing after writing to O_SYNC file or IS_SYNC inode"), so btrfs_write_inode() is actually unnecessary (and leads to a bunch of unnecessary commits). Get rid of it, which also gets rid of the deadlock. CC: stable@vger.kernel.org # 3.2+ Signed-off-by: Josef Bacik <jbacik@fb.com> [Omar: new commit message] Signed-off-by: Omar Sandoval <osandov@fb.com> Signed-off-by: David Sterba <dsterba@suse.com>
2018-08-06btrfs: drop extent_io_ops::set_range_writeback callbackDavid Sterba
The data and metadata callback implementation both use the same function. We can remove the call indirection and intermediate helper completely. Reviewed-by: Nikolay Borisov <nborisov@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2018-08-06btrfs: drop extent_io_ops::merge_bio_hook callbackDavid Sterba
The data and metadata callback implementation both use the same function. We can remove the call indirection completely. Reviewed-by: Nikolay Borisov <nborisov@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2018-08-06btrfs: drop extent_io_ops::tree_fs_info callbackDavid Sterba
All implementations of the callback are trivial and do the same and there's only one user. Merge everything together. Reviewed-by: Nikolay Borisov <nborisov@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2018-08-06btrfs: unify end_io callbacks of async_submit_bioDavid Sterba
The end_io callbacks passed to btrfs_wq_submit_bio (btrfs_submit_bio_done and btree_submit_bio_done) are effectively the same code, there's no point to do the indirection. Export btrfs_submit_bio_done and call it directly. Reviewed-by: Nikolay Borisov <nborisov@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2018-08-06btrfs: open-code bio_set_op_attrsDavid Sterba
The helper is trivial and marked as deprecated. Signed-off-by: David Sterba <dsterba@suse.com>
2018-08-06btrfs: prune unused includesDavid Sterba
Remove includes if none of the interfaces and exports is used in the given source file. Signed-off-by: David Sterba <dsterba@suse.com>
2018-08-06btrfs: simplify pointer chasing of local fs_info variablesDavid Sterba
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: simplify some assignments of inode numbersDavid Sterba
There are several places when the btrfs inode is converted to the generic inode, back to btrfs and then passed to btrfs_ino. We can remove the extra back and forth conversions. Signed-off-by: David Sterba <dsterba@suse.com>
2018-08-06btrfs: use timespec64 for i_otimeArnd Bergmann
While the regular inode timestamps all use timespec64 now, the i_otime field is btrfs specific and still needs to be converted to correctly represent times beyond 2038. Signed-off-by: Arnd Bergmann <arnd@arndb.de> 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: Get rid of the confusing btrfs_file_extent_inline_lenQu Wenruo
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>
2018-08-03btrfs: switch to discard_new_inode()Al Viro
Make sure that no partially set up inodes can be returned by open-by-handle. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>