summaryrefslogtreecommitdiff
path: root/fs/btrfs
AgeCommit message (Collapse)Author
2021-05-11Merge tag 'for-5.13-rc1-part2-tag' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux Pull btrfs fix from David Sterba: "Handle transaction start error in btrfs_fileattr_set() This is fix for code introduced by the new fileattr merge" * tag 'for-5.13-rc1-part2-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux: btrfs: handle transaction start error in btrfs_fileattr_set
2021-05-11btrfs: handle transaction start error in btrfs_fileattr_setRitesh Harjani
Add error handling in btrfs_fileattr_set in case of an error while starting a transaction. This fixes btrfs/232 which otherwise used to fail with below signature on Power. btrfs/232 [ 1119.474650] run fstests btrfs/232 at 2021-04-21 02:21:22 <...> [ 1366.638585] BUG: Unable to handle kernel data access on read at 0xffffffffffffff86 [ 1366.638768] Faulting instruction address: 0xc0000000009a5c88 cpu 0x0: Vector: 380 (Data SLB Access) at [c000000014f177b0] pc: c0000000009a5c88: btrfs_update_root_times+0x58/0xc0 lr: c0000000009a5c84: btrfs_update_root_times+0x54/0xc0 <...> pid = 24881, comm = fsstress btrfs_update_inode+0xa0/0x140 btrfs_fileattr_set+0x5d0/0x6f0 vfs_fileattr_set+0x2a8/0x390 do_vfs_ioctl+0x1290/0x1ac0 sys_ioctl+0x6c/0x120 system_call_exception+0x3d4/0x410 system_call_common+0xec/0x278 Fixes: 97fc29775487 ("btrfs: convert to fileattr") Signed-off-by: Ritesh Harjani <riteshh@linux.ibm.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2021-05-10Merge tag 'for-5.13-rc1-tag' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux Pull btrfs fixes from David Sterba: "First batch of various fixes, here's a list of notable ones: - fix unmountable seed device after fstrim - fix silent data loss in zoned mode due to ordered extent splitting - fix race leading to unpersisted data and metadata on fsync - fix deadlock when cloning inline extents and using qgroups" * tag 'for-5.13-rc1-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux: btrfs: initialize return variable in cleanup_free_space_cache_v1 btrfs: zoned: sanity check zone type btrfs: fix unmountable seed device after fstrim btrfs: fix deadlock when cloning inline extents and using qgroups btrfs: fix race leading to unpersisted data and metadata on fsync btrfs: do not consider send context as valid when trying to flush qgroups btrfs: zoned: fix silent data loss after failure splitting ordered extent
2021-05-05btrfs: use memzero_page() instead of open coded kmap patternIra Weiny
There are many places where kmap/memset/kunmap patterns occur. Use the newly lifted memzero_page() to eliminate direct uses of kmap and leverage the new core functions use of kmap_local_page(). The development of this patch was aided by the following coccinelle script: // <smpl> // SPDX-License-Identifier: GPL-2.0-only // Find kmap/memset/kunmap pattern and replace with memset*page calls // // NOTE: Offsets and other expressions may be more complex than what the script // will automatically generate. Therefore a catchall rule is provided to find // the pattern which then must be evaluated by hand. // // Confidence: Low // Copyright: (C) 2021 Intel Corporation // URL: http://coccinelle.lip6.fr/ // Comments: // Options: // // Then the memset pattern // @ memset_rule1 @ expression page, V, L, Off; identifier ptr; type VP; @@ ( -VP ptr = kmap(page); | -ptr = kmap(page); | -VP ptr = kmap_atomic(page); | -ptr = kmap_atomic(page); ) <+... ( -memset(ptr, 0, L); +memzero_page(page, 0, L); | -memset(ptr + Off, 0, L); +memzero_page(page, Off, L); | -memset(ptr, V, L); +memset_page(page, V, 0, L); | -memset(ptr + Off, V, L); +memset_page(page, V, Off, L); ) ...+> ( -kunmap(page); | -kunmap_atomic(ptr); ) // Remove any pointers left unused @ depends on memset_rule1 @ identifier memset_rule1.ptr; type VP, VP1; @@ -VP ptr; ... when != ptr; ? VP1 ptr; // // Catch all // @ memset_rule2 @ expression page; identifier ptr; expression GenTo, GenSize, GenValue; type VP; @@ ( -VP ptr = kmap(page); | -ptr = kmap(page); | -VP ptr = kmap_atomic(page); | -ptr = kmap_atomic(page); ) <+... ( // // Some call sites have complex expressions within the memset/memcpy // The follow are catch alls which need to be evaluated by hand. // -memset(GenTo, 0, GenSize); +memzero_pageExtra(page, GenTo, GenSize); | -memset(GenTo, GenValue, GenSize); +memset_pageExtra(page, GenValue, GenTo, GenSize); ) ...+> ( -kunmap(page); | -kunmap_atomic(ptr); ) // Remove any pointers left unused @ depends on memset_rule2 @ identifier memset_rule2.ptr; type VP, VP1; @@ -VP ptr; ... when != ptr; ? VP1 ptr; // </smpl> Link: https://lkml.kernel.org/r/20210309212137.2610186-4-ira.weiny@intel.com Signed-off-by: Ira Weiny <ira.weiny@intel.com> Reviewed-by: David Sterba <dsterba@suse.com> Cc: Alexander Viro <viro@zeniv.linux.org.uk> Cc: Chaitanya Kulkarni <chaitanya.kulkarni@wdc.com> Cc: Chris Mason <clm@fb.com> Cc: Josef Bacik <josef@toxicpanda.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-05-04btrfs: initialize return variable in cleanup_free_space_cache_v1Tom Rix
Static analysis reports this problem free-space-cache.c:3965:2: warning: Undefined or garbage value returned return ret; ^~~~~~~~~~ ret is set in the node handling loop. Treat doing nothing as a success and initialize ret to 0, although it's unlikely the loop would be skipped. We always have block groups, but as it could lead to transaction abort in the caller it's better to be safe. CC: stable@vger.kernel.org # 5.12+ Signed-off-by: Tom Rix <trix@redhat.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2021-05-04btrfs: zoned: sanity check zone typeNaohiro Aota
The fstests test case generic/475 creates a dm-linear device that gets changed to a dm-error device. This leads to errors in loading the block group's zone information when running on a zoned file system, ultimately resulting in a list corruption. When running on a kernel with list debugging enabled this leads to the following crash. BTRFS: error (device dm-2) in cleanup_transaction:1953: errno=-5 IO failure kernel BUG at lib/list_debug.c:54! invalid opcode: 0000 [#1] SMP PTI CPU: 1 PID: 2433 Comm: umount Tainted: G W 5.12.0+ #1018 RIP: 0010:__list_del_entry_valid.cold+0x1d/0x47 RSP: 0018:ffffc90001473df0 EFLAGS: 00010296 RAX: 0000000000000054 RBX: ffff8881038fd000 RCX: ffffc90001473c90 RDX: 0000000100001a31 RSI: 0000000000000003 RDI: 0000000000000003 RBP: ffff888308871108 R08: 0000000000000003 R09: 0000000000000001 R10: 3961373532383838 R11: 6666666620736177 R12: ffff888308871000 R13: ffff8881038fd088 R14: ffff8881038fdc78 R15: dead000000000100 FS: 00007f353c9b1540(0000) GS:ffff888627d00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f353cc2c710 CR3: 000000018e13c000 CR4: 00000000000006a0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: btrfs_free_block_groups+0xc9/0x310 [btrfs] close_ctree+0x2ee/0x31a [btrfs] ? call_rcu+0x8f/0x270 ? mutex_lock+0x1c/0x40 generic_shutdown_super+0x67/0x100 kill_anon_super+0x14/0x30 btrfs_kill_super+0x12/0x20 [btrfs] deactivate_locked_super+0x31/0x90 cleanup_mnt+0x13e/0x1b0 task_work_run+0x63/0xb0 exit_to_user_mode_loop+0xd9/0xe0 exit_to_user_mode_prepare+0x3e/0x60 syscall_exit_to_user_mode+0x1d/0x50 entry_SYSCALL_64_after_hwframe+0x44/0xae As dm-error has no support for zones, btrfs will run it's zone emulation mode on this device. The zone emulation mode emulates conventional zones, so bail out if the zone bitmap that gets populated on mount sees the zone as sequential while we're thinking it's a conventional zone when creating a block group. Note: this scenario is unlikely in a real wold application and can only happen by this (ab)use of device-mapper targets. CC: stable@vger.kernel.org # 5.12+ Signed-off-by: Naohiro Aota <naohiro.aota@wdc.com> Signed-off-by: Johannes Thumshirn <johannes.thumshirn@wdc.com> Signed-off-by: David Sterba <dsterba@suse.com>
2021-05-04btrfs: fix unmountable seed device after fstrimAnand Jain
The following test case reproduces an issue of wrongly freeing in-use blocks on the readonly seed device when fstrim is called on the rw sprout device. As shown below. Create a seed device and add a sprout device to it: $ mkfs.btrfs -fq -dsingle -msingle /dev/loop0 $ btrfstune -S 1 /dev/loop0 $ mount /dev/loop0 /btrfs $ btrfs dev add -f /dev/loop1 /btrfs BTRFS info (device loop0): relocating block group 290455552 flags system BTRFS info (device loop0): relocating block group 1048576 flags system BTRFS info (device loop0): disk added /dev/loop1 $ umount /btrfs Mount the sprout device and run fstrim: $ mount /dev/loop1 /btrfs $ fstrim /btrfs $ umount /btrfs Now try to mount the seed device, and it fails: $ mount /dev/loop0 /btrfs mount: /btrfs: wrong fs type, bad option, bad superblock on /dev/loop0, missing codepage or helper program, or other error. Block 5292032 is missing on the readonly seed device: $ dmesg -kt | tail <snip> BTRFS error (device loop0): bad tree block start, want 5292032 have 0 BTRFS warning (device loop0): couldn't read-tree root BTRFS error (device loop0): open_ctree failed From the dump-tree of the seed device (taken before the fstrim). Block 5292032 belonged to the block group starting at 5242880: $ btrfs inspect dump-tree -e /dev/loop0 | grep -A1 BLOCK_GROUP <snip> item 3 key (5242880 BLOCK_GROUP_ITEM 8388608) itemoff 16169 itemsize 24 block group used 114688 chunk_objectid 256 flags METADATA <snip> From the dump-tree of the sprout device (taken before the fstrim). fstrim used block-group 5242880 to find the related free space to free: $ btrfs inspect dump-tree -e /dev/loop1 | grep -A1 BLOCK_GROUP <snip> item 1 key (5242880 BLOCK_GROUP_ITEM 8388608) itemoff 16226 itemsize 24 block group used 32768 chunk_objectid 256 flags METADATA <snip> BPF kernel tracing the fstrim command finds the missing block 5292032 within the range of the discarded blocks as below: kprobe:btrfs_discard_extent { printf("freeing start %llu end %llu num_bytes %llu:\n", arg1, arg1+arg2, arg2); } freeing start 5259264 end 5406720 num_bytes 147456 <snip> Fix this by avoiding the discard command to the readonly seed device. Reported-by: Chris Murphy <lists@colorremedies.com> CC: stable@vger.kernel.org # 4.4+ Reviewed-by: Filipe Manana <fdmanana@suse.com> Signed-off-by: Anand Jain <anand.jain@oracle.com> Signed-off-by: David Sterba <dsterba@suse.com>
2021-04-28btrfs: fix deadlock when cloning inline extents and using qgroupsFilipe Manana
There are a few exceptional cases where cloning an inline extent needs to copy the inline extent data into a page of the destination inode. When this happens, we end up starting a transaction while having a dirty page for the destination inode and while having the range locked in the destination's inode iotree too. Because when reserving metadata space for a transaction we may need to flush existing delalloc in case there is not enough free space, we have a mechanism in place to prevent a deadlock, which was introduced in commit 3d45f221ce627d ("btrfs: fix deadlock when cloning inline extent and low on free metadata space"). However when using qgroups, a transaction also reserves metadata qgroup space, which can also result in flushing delalloc in case there is not enough available space at the moment. When this happens we deadlock, since flushing delalloc requires locking the file range in the inode's iotree and the range was already locked at the very beginning of the clone operation, before attempting to start the transaction. When this issue happens, stack traces like the following are reported: [72747.556262] task:kworker/u81:9 state:D stack: 0 pid: 225 ppid: 2 flags:0x00004000 [72747.556268] Workqueue: writeback wb_workfn (flush-btrfs-1142) [72747.556271] Call Trace: [72747.556273] __schedule+0x296/0x760 [72747.556277] schedule+0x3c/0xa0 [72747.556279] io_schedule+0x12/0x40 [72747.556284] __lock_page+0x13c/0x280 [72747.556287] ? generic_file_readonly_mmap+0x70/0x70 [72747.556325] extent_write_cache_pages+0x22a/0x440 [btrfs] [72747.556331] ? __set_page_dirty_nobuffers+0xe7/0x160 [72747.556358] ? set_extent_buffer_dirty+0x5e/0x80 [btrfs] [72747.556362] ? update_group_capacity+0x25/0x210 [72747.556366] ? cpumask_next_and+0x1a/0x20 [72747.556391] extent_writepages+0x44/0xa0 [btrfs] [72747.556394] do_writepages+0x41/0xd0 [72747.556398] __writeback_single_inode+0x39/0x2a0 [72747.556403] writeback_sb_inodes+0x1ea/0x440 [72747.556407] __writeback_inodes_wb+0x5f/0xc0 [72747.556410] wb_writeback+0x235/0x2b0 [72747.556414] ? get_nr_inodes+0x35/0x50 [72747.556417] wb_workfn+0x354/0x490 [72747.556420] ? newidle_balance+0x2c5/0x3e0 [72747.556424] process_one_work+0x1aa/0x340 [72747.556426] worker_thread+0x30/0x390 [72747.556429] ? create_worker+0x1a0/0x1a0 [72747.556432] kthread+0x116/0x130 [72747.556435] ? kthread_park+0x80/0x80 [72747.556438] ret_from_fork+0x1f/0x30 [72747.566958] Workqueue: btrfs-flush_delalloc btrfs_work_helper [btrfs] [72747.566961] Call Trace: [72747.566964] __schedule+0x296/0x760 [72747.566968] ? finish_wait+0x80/0x80 [72747.566970] schedule+0x3c/0xa0 [72747.566995] wait_extent_bit.constprop.68+0x13b/0x1c0 [btrfs] [72747.566999] ? finish_wait+0x80/0x80 [72747.567024] lock_extent_bits+0x37/0x90 [btrfs] [72747.567047] btrfs_invalidatepage+0x299/0x2c0 [btrfs] [72747.567051] ? find_get_pages_range_tag+0x2cd/0x380 [72747.567076] __extent_writepage+0x203/0x320 [btrfs] [72747.567102] extent_write_cache_pages+0x2bb/0x440 [btrfs] [72747.567106] ? update_load_avg+0x7e/0x5f0 [72747.567109] ? enqueue_entity+0xf4/0x6f0 [72747.567134] extent_writepages+0x44/0xa0 [btrfs] [72747.567137] ? enqueue_task_fair+0x93/0x6f0 [72747.567140] do_writepages+0x41/0xd0 [72747.567144] __filemap_fdatawrite_range+0xc7/0x100 [72747.567167] btrfs_run_delalloc_work+0x17/0x40 [btrfs] [72747.567195] btrfs_work_helper+0xc2/0x300 [btrfs] [72747.567200] process_one_work+0x1aa/0x340 [72747.567202] worker_thread+0x30/0x390 [72747.567205] ? create_worker+0x1a0/0x1a0 [72747.567208] kthread+0x116/0x130 [72747.567211] ? kthread_park+0x80/0x80 [72747.567214] ret_from_fork+0x1f/0x30 [72747.569686] task:fsstress state:D stack: 0 pid:841421 ppid:841417 flags:0x00000000 [72747.569689] Call Trace: [72747.569691] __schedule+0x296/0x760 [72747.569694] schedule+0x3c/0xa0 [72747.569721] try_flush_qgroup+0x95/0x140 [btrfs] [72747.569725] ? finish_wait+0x80/0x80 [72747.569753] btrfs_qgroup_reserve_data+0x34/0x50 [btrfs] [72747.569781] btrfs_check_data_free_space+0x5f/0xa0 [btrfs] [72747.569804] btrfs_buffered_write+0x1f7/0x7f0 [btrfs] [72747.569810] ? path_lookupat.isra.48+0x97/0x140 [72747.569833] btrfs_file_write_iter+0x81/0x410 [btrfs] [72747.569836] ? __kmalloc+0x16a/0x2c0 [72747.569839] do_iter_readv_writev+0x160/0x1c0 [72747.569843] do_iter_write+0x80/0x1b0 [72747.569847] vfs_writev+0x84/0x140 [72747.569869] ? btrfs_file_llseek+0x38/0x270 [btrfs] [72747.569873] do_writev+0x65/0x100 [72747.569876] do_syscall_64+0x33/0x40 [72747.569879] entry_SYSCALL_64_after_hwframe+0x44/0xa9 [72747.569899] task:fsstress state:D stack: 0 pid:841424 ppid:841417 flags:0x00004000 [72747.569903] Call Trace: [72747.569906] __schedule+0x296/0x760 [72747.569909] schedule+0x3c/0xa0 [72747.569936] try_flush_qgroup+0x95/0x140 [btrfs] [72747.569940] ? finish_wait+0x80/0x80 [72747.569967] __btrfs_qgroup_reserve_meta+0x36/0x50 [btrfs] [72747.569989] start_transaction+0x279/0x580 [btrfs] [72747.570014] clone_copy_inline_extent+0x332/0x490 [btrfs] [72747.570041] btrfs_clone+0x5b7/0x7a0 [btrfs] [72747.570068] ? lock_extent_bits+0x64/0x90 [btrfs] [72747.570095] btrfs_clone_files+0xfc/0x150 [btrfs] [72747.570122] btrfs_remap_file_range+0x3d8/0x4a0 [btrfs] [72747.570126] do_clone_file_range+0xed/0x200 [72747.570131] vfs_clone_file_range+0x37/0x110 [72747.570134] ioctl_file_clone+0x7d/0xb0 [72747.570137] do_vfs_ioctl+0x138/0x630 [72747.570140] __x64_sys_ioctl+0x62/0xc0 [72747.570143] do_syscall_64+0x33/0x40 [72747.570146] entry_SYSCALL_64_after_hwframe+0x44/0xa9 So fix this by skipping the flush of delalloc for an inode that is flagged with BTRFS_INODE_NO_DELALLOC_FLUSH, meaning it is currently under such a special case of cloning an inline extent, when flushing delalloc during qgroup metadata reservation. The special cases for cloning inline extents were added in kernel 5.7 by by commit 05a5a7621ce66c ("Btrfs: implement full reflink support for inline extents"), while having qgroup metadata space reservation flushing delalloc when low on space was added in kernel 5.9 by commit c53e9653605dbf ("btrfs: qgroup: try to flush qgroup space when we get -EDQUOT"). So use a "Fixes:" tag for the later commit to ease stable kernel backports. Reported-by: Wang Yugui <wangyugui@e16-tech.com> Link: https://lore.kernel.org/linux-btrfs/20210421083137.31E3.409509F4@e16-tech.com/ Fixes: c53e9653605dbf ("btrfs: qgroup: try to flush qgroup space when we get -EDQUOT") CC: stable@vger.kernel.org # 5.9+ 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>
2021-04-28btrfs: fix race leading to unpersisted data and metadata on fsyncFilipe Manana
When doing a fast fsync on a file, there is a race which can result in the fsync returning success to user space without logging the inode and without durably persisting new data. The following example shows one possible scenario for this: $ mkfs.btrfs -f /dev/sdc $ mount /dev/sdc /mnt $ touch /mnt/bar $ xfs_io -f -c "pwrite -S 0xab 0 1M" -c "fsync" /mnt/baz # Now we have: # file bar == inode 257 # file baz == inode 258 $ mv /mnt/baz /mnt/foo # Now we have: # file bar == inode 257 # file foo == inode 258 $ xfs_io -c "pwrite -S 0xcd 0 1M" /mnt/foo # fsync bar before foo, it is important to trigger the race. $ xfs_io -c "fsync" /mnt/bar $ xfs_io -c "fsync" /mnt/foo # After this: # inode 257, file bar, is empty # inode 258, file foo, has 1M filled with 0xcd <power failure> # Replay the log: $ mount /dev/sdc /mnt # After this point file foo should have 1M filled with 0xcd and not 0xab The following steps explain how the race happens: 1) Before the first fsync of inode 258, when it has the "baz" name, its ->logged_trans is 0, ->last_sub_trans is 0 and ->last_log_commit is -1. The inode also has the full sync flag set; 2) After the first fsync, we set inode 258 ->logged_trans to 6, which is the generation of the current transaction, and set ->last_log_commit to 0, which is the current value of ->last_sub_trans (done at btrfs_log_inode()). The full sync flag is cleared from the inode during the fsync. The log sub transaction that was committed had an ID of 0 and when we synced the log, at btrfs_sync_log(), we incremented root->log_transid from 0 to 1; 3) During the rename: We update inode 258, through btrfs_update_inode(), and that causes its ->last_sub_trans to be set to 1 (the current log transaction ID), and ->last_log_commit remains with a value of 0. After updating inode 258, because we have previously logged the inode in the previous fsync, we log again the inode through the call to btrfs_log_new_name(). This results in updating the inode's ->last_log_commit from 0 to 1 (the current value of its ->last_sub_trans). The ->last_sub_trans of inode 257 is updated to 1, which is the ID of the next log transaction; 4) Then a buffered write against inode 258 is made. This leaves the value of ->last_sub_trans as 1 (the ID of the current log transaction, stored at root->log_transid); 5) Then an fsync against inode 257 (or any other inode other than 258), happens. This results in committing the log transaction with ID 1, which results in updating root->last_log_commit to 1 and bumping root->log_transid from 1 to 2; 6) Then an fsync against inode 258 starts. We flush delalloc and wait only for writeback to complete, since the full sync flag is not set in the inode's runtime flags - we do not wait for ordered extents to complete. Then, at btrfs_sync_file(), we call btrfs_inode_in_log() before the ordered extent completes. The call returns true: static inline bool btrfs_inode_in_log(...) { bool ret = false; spin_lock(&inode->lock); if (inode->logged_trans == generation && inode->last_sub_trans <= inode->last_log_commit && inode->last_sub_trans <= inode->root->last_log_commit) ret = true; spin_unlock(&inode->lock); return ret; } generation has a value of 6 (fs_info->generation), ->logged_trans also has a value of 6 (set when we logged the inode during the first fsync and when logging it during the rename), ->last_sub_trans has a value of 1, set during the rename (step 3), ->last_log_commit also has a value of 1 (set in step 3) and root->last_log_commit has a value of 1, which was set in step 5 when fsyncing inode 257. As a consequence we don't log the inode, any new extents and do not sync the log, resulting in a data loss if a power failure happens after the fsync and before the current transaction commits. Also, because we do not log the inode, after a power failure the mtime and ctime of the inode do not match those we had before. When the ordered extent completes before we call btrfs_inode_in_log(), then the call returns false and we log the inode and sync the log, since at the end of ordered extent completion we update the inode and set ->last_sub_trans to 2 (the value of root->log_transid) and ->last_log_commit to 1. This problem is found after removing the check for the emptiness of the inode's list of modified extents in the recent commit 209ecbb8585bf6 ("btrfs: remove stale comment and logic from btrfs_inode_in_log()"), added in the 5.13 merge window. However checking the emptiness of the list is not really the way to solve this problem, and was never intended to, because while that solves the problem for COW writes, the problem persists for NOCOW writes because in that case the list is always empty. In the case of NOCOW writes, even though we wait for the writeback to complete before returning from btrfs_sync_file(), we end up not logging the inode, which has a new mtime/ctime, and because we don't sync the log, we never issue disk barriers (send REQ_PREFLUSH to the device) since that only happens when we sync the log (when we write super blocks at btrfs_sync_log()). So effectively, for a NOCOW case, when we return from btrfs_sync_file() to user space, we are not guaranteeing that the data is durably persisted on disk. Also, while the example above uses a rename exchange to show how the problem happens, it is not the only way to trigger it. An alternative could be adding a new hard link to inode 258, since that also results in calling btrfs_log_new_name() and updating the inode in the log. An example reproducer using the addition of a hard link instead of a rename operation: $ mkfs.btrfs -f /dev/sdc $ mount /dev/sdc /mnt $ touch /mnt/bar $ xfs_io -f -c "pwrite -S 0xab 0 1M" -c "fsync" /mnt/foo $ ln /mnt/foo /mnt/foo_link $ xfs_io -c "pwrite -S 0xcd 0 1M" /mnt/foo $ xfs_io -c "fsync" /mnt/bar $ xfs_io -c "fsync" /mnt/foo <power failure> # Replay the log: $ mount /dev/sdc /mnt # After this point file foo often has 1M filled with 0xab and not 0xcd The reasons leading to the final fsync of file foo, inode 258, not persisting the new data are the same as for the previous example with a rename operation. So fix by never skipping logging and log syncing when there are still any ordered extents in flight. To avoid making the conditional if statement that checks if logging an inode is needed harder to read, place all the logic into an helper function with separate if statements to make it more manageable and easier to read. A test case for fstests will follow soon. For NOCOW writes, the problem existed before commit b5e6c3e170b770 ("btrfs: always wait on ordered extents at fsync time"), introduced in kernel 4.19, then it went away with that commit since we started to always wait for ordered extent completion before logging. The problem came back again once the fast fsync path was changed again to avoid waiting for ordered extent completion, in commit 487781796d3022 ("btrfs: make fast fsyncs wait only for writeback"), added in kernel 5.10. However, for COW writes, the race only happens after the recent commit 209ecbb8585bf6 ("btrfs: remove stale comment and logic from btrfs_inode_in_log()"), introduced in the 5.13 merge window. For NOCOW writes, the bug existed before that commit. So tag 5.10+ as the release for stable backports. CC: stable@vger.kernel.org # 5.10+ Signed-off-by: Filipe Manana <fdmanana@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2021-04-28btrfs: do not consider send context as valid when trying to flush qgroupsFilipe Manana
At qgroup.c:try_flush_qgroup() we are asserting that current->journal_info is either NULL or has the value BTRFS_SEND_TRANS_STUB. However allowing for BTRFS_SEND_TRANS_STUB makes no sense because: 1) It is misleading, because send operations are read-only and do not ever need to reserve qgroup space; 2) We already assert that current->journal_info != BTRFS_SEND_TRANS_STUB at transaction.c:start_transaction(); 3) On a kernel without CONFIG_BTRFS_ASSERT=y set, it would result in a crash if try_flush_qgroup() is ever called in a send context, because at transaction.c:start_transaction we cast current->journal_info into a struct btrfs_trans_handle pointer and then dereference it. So just do allow a send context at try_flush_qgroup() and update the comment about it. 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>
2021-04-28btrfs: zoned: fix silent data loss after failure splitting ordered extentFilipe Manana
On a zoned filesystem, sometimes we need to split an ordered extent into 3 different ordered extents. The original ordered extent is shortened, at the front and at the rear, and we create two other new ordered extents to represent the trimmed parts of the original ordered extent. After adjusting the original ordered extent, we create an ordered extent to represent the pre-range, and that may fail with ENOMEM for example. After that we always try to create the ordered extent for the post-range, and if that happens to succeed we end up returning success to the caller as we overwrite the 'ret' variable which contained the previous error. This means we end up with a file range for which there is no ordered extent, which results in the range never getting a new file extent item pointing to the new data location. And since the split operation did not return an error, writeback does not fail and the inode's mapping is not flagged with an error, resulting in a subsequent fsync not reporting an error either. It's possibly very unlikely to have the creation of the post-range ordered extent succeed after the creation of the pre-range ordered extent failed, but it's not impossible. So fix this by making sure we only create the post-range ordered extent if there was no error creating the ordered extent for the pre-range. Fixes: d22002fd37bd97 ("btrfs: zoned: split ordered extent when bio is sent") CC: stable@vger.kernel.org # 5.12+ Signed-off-by: Filipe Manana <fdmanana@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2021-04-27Merge branch 'miklos.fileattr' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs Pull fileattr conversion updates from Miklos Szeredi via Al Viro: "This splits the handling of FS_IOC_[GS]ETFLAGS from ->ioctl() into a separate method. The interface is reasonably uniform across the filesystems that support it and gives nice boilerplate removal" * 'miklos.fileattr' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (23 commits) ovl: remove unneeded ioctls fuse: convert to fileattr fuse: add internal open/release helpers fuse: unsigned open flags fuse: move ioctl to separate source file vfs: remove unused ioctl helpers ubifs: convert to fileattr reiserfs: convert to fileattr ocfs2: convert to fileattr nilfs2: convert to fileattr jfs: convert to fileattr hfsplus: convert to fileattr efivars: convert to fileattr xfs: convert to fileattr orangefs: convert to fileattr gfs2: convert to fileattr f2fs: convert to fileattr ext4: convert to fileattr ext2: convert to fileattr btrfs: convert to fileattr ...
2021-04-27Merge tag 'cfi-v5.13-rc1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux Pull CFI on arm64 support from Kees Cook: "This builds on last cycle's LTO work, and allows the arm64 kernels to be built with Clang's Control Flow Integrity feature. This feature has happily lived in Android kernels for almost 3 years[1], so I'm excited to have it ready for upstream. The wide diffstat is mainly due to the treewide fixing of mismatched list_sort prototypes. Other things in core kernel are to address various CFI corner cases. The largest code portion is the CFI runtime implementation itself (which will be shared by all architectures implementing support for CFI). The arm64 pieces are Acked by arm64 maintainers rather than coming through the arm64 tree since carrying this tree over there was going to be awkward. CFI support for x86 is still under development, but is pretty close. There are a handful of corner cases on x86 that need some improvements to Clang and objtool, but otherwise works well. Summary: - Clean up list_sort prototypes (Sami Tolvanen) - Introduce CONFIG_CFI_CLANG for arm64 (Sami Tolvanen)" * tag 'cfi-v5.13-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux: arm64: allow CONFIG_CFI_CLANG to be selected KVM: arm64: Disable CFI for nVHE arm64: ftrace: use function_nocfi for ftrace_call arm64: add __nocfi to __apply_alternatives arm64: add __nocfi to functions that jump to a physical address arm64: use function_nocfi with __pa_symbol arm64: implement function_nocfi psci: use function_nocfi for cpu_resume lkdtm: use function_nocfi treewide: Change list_sort to use const pointers bpf: disable CFI in dispatcher functions kallsyms: strip ThinLTO hashes from static functions kthread: use WARN_ON_FUNCTION_MISMATCH workqueue: use WARN_ON_FUNCTION_MISMATCH module: ensure __cfi_check alignment mm: add generic function_nocfi macro cfi: add __cficanonical add support for Clang CFI
2021-04-20btrfs: zoned: automatically reclaim zonesJohannes Thumshirn
When a file gets deleted on a zoned file system, the space freed is not returned back into the block group's free space, but is migrated to zone_unusable. As this zone_unusable space is behind the current write pointer it is not possible to use it for new allocations. In the current implementation a zone is reset once all of the block group's space is accounted as zone unusable. This behaviour can lead to premature ENOSPC errors on a busy file system. Instead of only reclaiming the zone once it is completely unusable, kick off a reclaim job once the amount of unusable bytes exceeds a user configurable threshold between 51% and 100%. It can be set per mounted filesystem via the sysfs tunable bg_reclaim_threshold which is set to 75% by default. Similar to reclaiming unused block groups, these dirty block groups are added to a to_reclaim list and then on a transaction commit, the reclaim process is triggered but after we deleted unused block groups, which will free space for the relocation process. Reviewed-by: Filipe Manana <fdmanana@suse.com> Signed-off-by: Johannes Thumshirn <johannes.thumshirn@wdc.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2021-04-20btrfs: rename delete_unused_bgs_mutex to reclaim_bgs_lockJohannes Thumshirn
As a preparation for extending the block group deletion use case, rename the unused_bgs_mutex to reclaim_bgs_lock. Reviewed-by: Filipe Manana <fdmanana@suse.com> Reviewed-by: Josef Bacik <josef@toxicpanda.com> Signed-off-by: Johannes Thumshirn <johannes.thumshirn@wdc.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2021-04-20btrfs: zoned: reset zones of relocated block groupsJohannes Thumshirn
When relocating a block group the freed up space is not discarded in one big block, but each extent is discarded on its own with -odisard=sync. For a zoned filesystem we need to discard the whole block group at once, so btrfs_discard_extent() will translate the discard into a REQ_OP_ZONE_RESET operation, which then resets the device's zone. Failure to reset the zone is not fatal error. Discussion about the approach and regarding transaction blocking: https://lore.kernel.org/linux-btrfs/CAL3q7H4SjS_d5rBepfTMhU8Th3bJzdmyYd0g4Z60yUgC_rC_ZA@mail.gmail.com/ Reviewed-by: Josef Bacik <josef@toxicpanda.com> Reviewed-by: Filipe Manana <fdmanana@suse.com> Signed-off-by: Johannes Thumshirn <johannes.thumshirn@wdc.com> Signed-off-by: David Sterba <dsterba@suse.com>
2021-04-20btrfs: more graceful errors/warnings on 32bit systems when reaching limitsQu Wenruo
Btrfs uses internally mapped u64 address space for all its metadata. Due to the page cache limit on 32bit systems, btrfs can't access metadata at or beyond (ULONG_MAX + 1) << PAGE_SHIFT. See how MAX_LFS_FILESIZE and page::index are defined. This is 16T for 4K page size while 256T for 64K page size. Users can have a filesystem which doesn't have metadata beyond the boundary at mount time, but later balance can cause it to create metadata beyond the boundary. And modification to MM layer is unrealistic just for such minor use case. We can't do more than to prevent mounting such filesystem or warn early when the numbers are still within the limits. To address such problem, this patch will introduce the following checks: - Mount time rejection This will reject any fs which has metadata chunk at or beyond the boundary. - Mount time early warning If there is any metadata chunk beyond 5/8th of the boundary, we do an early warning and hope the end user will see it. - Runtime extent buffer rejection If we're going to allocate an extent buffer at or beyond the boundary, reject such request with EOVERFLOW. This is definitely going to cause problems like transaction abort, but we have no better ways. - Runtime extent buffer early warning If an extent buffer beyond 5/8th of the max file size is allocated, do an early warning. Above error/warning message will only be printed once for each fs to reduce dmesg flood. If the mount is rejected, the filesystem will be mountable only on a 64bit host. Link: https://lore.kernel.org/linux-btrfs/1783f16d-7a28-80e6-4c32-fdf19b705ed0@gmx.com/ Reported-by: Erik Jensen <erikjensen@rkjnsn.net> Reviewed-by: Josef Bacik <josef@toxicpanda.com> Signed-off-by: Qu Wenruo <wqu@suse.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2021-04-20btrfs: zoned: fix unpaired block group unfreeze during device replaceFilipe Manana
When doing a device replace on a zoned filesystem, if we find a block group with ->to_copy == 0, we jump to the label 'done', which will result in later calling btrfs_unfreeze_block_group(), even though at this point we never called btrfs_freeze_block_group(). Since at this point we have neither turned the block group to RO mode nor made any progress, we don't need to jump to the label 'done'. So fix this by jumping instead to the label 'skip' and dropping our reference on the block group before the jump. Fixes: 78ce9fc269af6e ("btrfs: zoned: mark block groups to copy for device-replace") CC: stable@vger.kernel.org # 5.12 Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com> Signed-off-by: Filipe Manana <fdmanana@suse.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2021-04-20btrfs: fix race when picking most recent mod log operation for an old rootFilipe Manana
Commit dbcc7d57bffc0c ("btrfs: fix race when cloning extent buffer during rewind of an old root"), fixed a race when we need to rewind the extent buffer of an old root. It was caused by picking a new mod log operation for the extent buffer while getting a cloned extent buffer with an outdated number of items (off by -1), because we cloned the extent buffer without locking it first. However there is still another similar race, but in the opposite direction. The cloned extent buffer has a number of items that does not match the number of tree mod log operations that are going to be replayed. This is because right after we got the last (most recent) tree mod log operation to replay and before locking and cloning the extent buffer, another task adds a new pointer to the extent buffer, which results in adding a new tree mod log operation and incrementing the number of items in the extent buffer. So after cloning we have mismatch between the number of items in the extent buffer and the number of mod log operations we are going to apply to it. This results in hitting a BUG_ON() that produces the following stack trace: ------------[ cut here ]------------ kernel BUG at fs/btrfs/tree-mod-log.c:675! invalid opcode: 0000 [#1] SMP KASAN PTI CPU: 3 PID: 4811 Comm: crawl_1215 Tainted: G W 5.12.0-7d1efdf501f8-misc-next+ #99 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.12.0-1 04/01/2014 RIP: 0010:tree_mod_log_rewind+0x3b1/0x3c0 Code: 05 48 8d 74 10 (...) RSP: 0018:ffffc90001027090 EFLAGS: 00010293 RAX: 0000000000000000 RBX: ffff8880a8514600 RCX: ffffffffaa9e59b6 RDX: 0000000000000007 RSI: dffffc0000000000 RDI: ffff8880a851462c RBP: ffffc900010270e0 R08: 00000000000000c0 R09: ffffed1004333417 R10: ffff88802199a0b7 R11: ffffed1004333416 R12: 000000000000000e R13: ffff888135af8748 R14: ffff88818766ff00 R15: ffff8880a851462c FS: 00007f29acf62700(0000) GS:ffff8881f2200000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f0e6013f718 CR3: 000000010d42e003 CR4: 0000000000170ee0 Call Trace: btrfs_get_old_root+0x16a/0x5c0 ? lock_downgrade+0x400/0x400 btrfs_search_old_slot+0x192/0x520 ? btrfs_search_slot+0x1090/0x1090 ? free_extent_buffer.part.61+0xd7/0x140 ? free_extent_buffer+0x13/0x20 resolve_indirect_refs+0x3e9/0xfc0 ? lock_downgrade+0x400/0x400 ? __kasan_check_read+0x11/0x20 ? add_prelim_ref.part.11+0x150/0x150 ? lock_downgrade+0x400/0x400 ? __kasan_check_read+0x11/0x20 ? lock_acquired+0xbb/0x620 ? __kasan_check_write+0x14/0x20 ? do_raw_spin_unlock+0xa8/0x140 ? rb_insert_color+0x340/0x360 ? prelim_ref_insert+0x12d/0x430 find_parent_nodes+0x5c3/0x1830 ? stack_trace_save+0x87/0xb0 ? resolve_indirect_refs+0xfc0/0xfc0 ? fs_reclaim_acquire+0x67/0xf0 ? __kasan_check_read+0x11/0x20 ? lockdep_hardirqs_on_prepare+0x210/0x210 ? fs_reclaim_acquire+0x67/0xf0 ? __kasan_check_read+0x11/0x20 ? ___might_sleep+0x10f/0x1e0 ? __kasan_kmalloc+0x9d/0xd0 ? trace_hardirqs_on+0x55/0x120 btrfs_find_all_roots_safe+0x142/0x1e0 ? find_parent_nodes+0x1830/0x1830 ? trace_hardirqs_on+0x55/0x120 ? ulist_free+0x1f/0x30 ? btrfs_inode_flags_to_xflags+0x50/0x50 iterate_extent_inodes+0x20e/0x580 ? tree_backref_for_extent+0x230/0x230 ? release_extent_buffer+0x225/0x280 ? read_extent_buffer+0xdd/0x110 ? lock_downgrade+0x400/0x400 ? __kasan_check_read+0x11/0x20 ? lock_acquired+0xbb/0x620 ? __kasan_check_write+0x14/0x20 ? do_raw_spin_unlock+0xa8/0x140 ? _raw_spin_unlock+0x22/0x30 ? release_extent_buffer+0x225/0x280 iterate_inodes_from_logical+0x129/0x170 ? iterate_inodes_from_logical+0x129/0x170 ? btrfs_inode_flags_to_xflags+0x50/0x50 ? iterate_extent_inodes+0x580/0x580 ? __vmalloc_node+0x92/0xb0 ? init_data_container+0x34/0xb0 ? init_data_container+0x34/0xb0 ? kvmalloc_node+0x60/0x80 btrfs_ioctl_logical_to_ino+0x158/0x230 btrfs_ioctl+0x2038/0x4360 ? __kasan_check_write+0x14/0x20 ? mmput+0x3b/0x220 ? btrfs_ioctl_get_supported_features+0x30/0x30 ? __kasan_check_read+0x11/0x20 ? __kasan_check_read+0x11/0x20 ? lock_release+0xc8/0x650 ? __might_fault+0x64/0xd0 ? __kasan_check_read+0x11/0x20 ? lock_downgrade+0x400/0x400 ? lockdep_hardirqs_on_prepare+0x210/0x210 ? lockdep_hardirqs_on_prepare+0x13/0x210 ? _raw_spin_unlock_irqrestore+0x51/0x63 ? __kasan_check_read+0x11/0x20 ? do_vfs_ioctl+0xfc/0x9d0 ? ioctl_file_clone+0xe0/0xe0 ? lock_downgrade+0x400/0x400 ? lockdep_hardirqs_on_prepare+0x210/0x210 ? __kasan_check_read+0x11/0x20 ? lock_release+0xc8/0x650 ? __task_pid_nr_ns+0xd3/0x250 ? __kasan_check_read+0x11/0x20 ? __fget_files+0x160/0x230 ? __fget_light+0xf2/0x110 __x64_sys_ioctl+0xc3/0x100 do_syscall_64+0x37/0x80 entry_SYSCALL_64_after_hwframe+0x44/0xae RIP: 0033:0x7f29ae85b427 Code: 00 00 90 48 8b (...) RSP: 002b:00007f29acf5fcf8 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 00007f29acf5ff40 RCX: 00007f29ae85b427 RDX: 00007f29acf5ff48 RSI: 00000000c038943b RDI: 0000000000000003 RBP: 0000000001000000 R08: 0000000000000000 R09: 00007f29acf60120 R10: 00005640d5fc7b00 R11: 0000000000000246 R12: 0000000000000003 R13: 00007f29acf5ff48 R14: 00007f29acf5ff40 R15: 00007f29acf5fef8 Modules linked in: ---[ end trace 85e5fce078dfbe04 ]--- (gdb) l *(tree_mod_log_rewind+0x3b1) 0xffffffff819e5b21 is in tree_mod_log_rewind (fs/btrfs/tree-mod-log.c:675). 670 * the modification. As we're going backwards, we do the 671 * opposite of each operation here. 672 */ 673 switch (tm->op) { 674 case BTRFS_MOD_LOG_KEY_REMOVE_WHILE_FREEING: 675 BUG_ON(tm->slot < n); 676 fallthrough; 677 case BTRFS_MOD_LOG_KEY_REMOVE_WHILE_MOVING: 678 case BTRFS_MOD_LOG_KEY_REMOVE: 679 btrfs_set_node_key(eb, &tm->key, tm->slot); (gdb) quit The following steps explain in more detail how it happens: 1) We have one tree mod log user (through fiemap or the logical ino ioctl), with a sequence number of 1, so we have fs_info->tree_mod_seq == 1. This is task A; 2) Another task is at ctree.c:balance_level() and we have eb X currently as the root of the tree, and we promote its single child, eb Y, as the new root. Then, at ctree.c:balance_level(), we call: ret = btrfs_tree_mod_log_insert_root(root->node, child, true); 3) At btrfs_tree_mod_log_insert_root() we create a tree mod log operation of type BTRFS_MOD_LOG_KEY_REMOVE_WHILE_FREEING, with a ->logical field pointing to ebX->start. We only have one item in eb X, so we create only one tree mod log operation, and store in the "tm_list" array; 4) Then, still at btrfs_tree_mod_log_insert_root(), we create a tree mod log element of operation type BTRFS_MOD_LOG_ROOT_REPLACE, ->logical set to ebY->start, ->old_root.logical set to ebX->start, ->old_root.level set to the level of eb X and ->generation set to the generation of eb X; 5) Then btrfs_tree_mod_log_insert_root() calls tree_mod_log_free_eb() with "tm_list" as argument. After that, tree_mod_log_free_eb() calls tree_mod_log_insert(). This inserts the mod log operation of type BTRFS_MOD_LOG_KEY_REMOVE_WHILE_FREEING from step 3 into the rbtree with a sequence number of 2 (and fs_info->tree_mod_seq set to 2); 6) Then, after inserting the "tm_list" single element into the tree mod log rbtree, the BTRFS_MOD_LOG_ROOT_REPLACE element is inserted, which gets the sequence number 3 (and fs_info->tree_mod_seq set to 3); 7) Back to ctree.c:balance_level(), we free eb X by calling btrfs_free_tree_block() on it. Because eb X was created in the current transaction, has no other references and writeback did not happen for it, we add it back to the free space cache/tree; 8) Later some other task B allocates the metadata extent from eb X, since it is marked as free space in the space cache/tree, and uses it as a node for some other btree; 9) The tree mod log user task calls btrfs_search_old_slot(), which calls btrfs_get_old_root(), and finally that calls tree_mod_log_oldest_root() with time_seq == 1 and eb_root == eb Y; 10) The first iteration of the while loop finds the tree mod log element with sequence number 3, for the logical address of eb Y and of type BTRFS_MOD_LOG_ROOT_REPLACE; 11) Because the operation type is BTRFS_MOD_LOG_ROOT_REPLACE, we don't break out of the loop, and set root_logical to point to tm->old_root.logical, which corresponds to the logical address of eb X; 12) On the next iteration of the while loop, the call to tree_mod_log_search_oldest() returns the smallest tree mod log element for the logical address of eb X, which has a sequence number of 2, an operation type of BTRFS_MOD_LOG_KEY_REMOVE_WHILE_FREEING and corresponds to the old slot 0 of eb X (eb X had only 1 item in it before being freed at step 7); 13) We then break out of the while loop and return the tree mod log operation of type BTRFS_MOD_LOG_ROOT_REPLACE (eb Y), and not the one for slot 0 of eb X, to btrfs_get_old_root(); 14) At btrfs_get_old_root(), we process the BTRFS_MOD_LOG_ROOT_REPLACE operation and set "logical" to the logical address of eb X, which was the old root. We then call tree_mod_log_search() passing it the logical address of eb X and time_seq == 1; 15) But before calling tree_mod_log_search(), task B locks eb X, adds a key to eb X, which results in adding a tree mod log operation of type BTRFS_MOD_LOG_KEY_ADD, with a sequence number of 4, to the tree mod log, and increments the number of items in eb X from 0 to 1. Now fs_info->tree_mod_seq has a value of 4; 16) Task A then calls tree_mod_log_search(), which returns the most recent tree mod log operation for eb X, which is the one just added by task B at the previous step, with a sequence number of 4, a type of BTRFS_MOD_LOG_KEY_ADD and for slot 0; 17) Before task A locks and clones eb X, task A adds another key to eb X, which results in adding a new BTRFS_MOD_LOG_KEY_ADD mod log operation, with a sequence number of 5, for slot 1 of eb X, increments the number of items in eb X from 1 to 2, and unlocks eb X. Now fs_info->tree_mod_seq has a value of 5; 18) Task A then locks eb X and clones it. The clone has a value of 2 for the number of items and the pointer "tm" points to the tree mod log operation with sequence number 4, not the most recent one with a sequence number of 5, so there is mismatch between the number of mod log operations that are going to be applied to the cloned version of eb X and the number of items in the clone; 19) Task A then calls tree_mod_log_rewind() with the clone of eb X, the tree mod log operation with sequence number 4 and a type of BTRFS_MOD_LOG_KEY_ADD, and time_seq == 1; 20) At tree_mod_log_rewind(), we set the local variable "n" with a value of 2, which is the number of items in the clone of eb X. Then in the first iteration of the while loop, we process the mod log operation with sequence number 4, which is targeted at slot 0 and has a type of BTRFS_MOD_LOG_KEY_ADD. This results in decrementing "n" from 2 to 1. Then we pick the next tree mod log operation for eb X, which is the tree mod log operation with a sequence number of 2, a type of BTRFS_MOD_LOG_KEY_REMOVE_WHILE_FREEING and for slot 0, it is the one added in step 5 to the tree mod log tree. We go back to the top of the loop to process this mod log operation, and because its slot is 0 and "n" has a value of 1, we hit the BUG_ON: (...) switch (tm->op) { case BTRFS_MOD_LOG_KEY_REMOVE_WHILE_FREEING: BUG_ON(tm->slot < n); fallthrough; (...) Fix this by checking for a more recent tree mod log operation after locking and cloning the extent buffer of the old root node, and use it as the first operation to apply to the cloned extent buffer when rewinding it. Stable backport notes: due to moved code and renames, in =< 5.11 the change should be applied to ctree.c:get_old_root. Reported-by: Zygo Blaxell <ce3g8jdj@umail.furryterror.org> Link: https://lore.kernel.org/linux-btrfs/20210404040732.GZ32440@hungrycats.org/ Fixes: 834328a8493079 ("Btrfs: tree mod log's old roots could still be part of the tree") CC: stable@vger.kernel.org # 4.4+ Signed-off-by: Filipe Manana <fdmanana@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2021-04-20btrfs: fix metadata extent leak after failure to create subvolumeFilipe Manana
When creating a subvolume we allocate an extent buffer for its root node after starting a transaction. We setup a root item for the subvolume that points to that extent buffer and then attempt to insert the root item into the root tree - however if that fails, due to ENOMEM for example, we do not free the extent buffer previously allocated and we do not abort the transaction (as at that point we did nothing that can not be undone). This means that we effectively do not return the metadata extent back to the free space cache/tree and we leave a delayed reference for it which causes a metadata extent item to be added to the extent tree, in the next transaction commit, without having backreferences. When this happens 'btrfs check' reports the following: $ btrfs check /dev/sdi Opening filesystem to check... Checking filesystem on /dev/sdi UUID: dce2cb9d-025f-4b05-a4bf-cee0ad3785eb [1/7] checking root items [2/7] checking extents ref mismatch on [30425088 16384] extent item 1, found 0 backref 30425088 root 256 not referenced back 0x564a91c23d70 incorrect global backref count on 30425088 found 1 wanted 0 backpointer mismatch on [30425088 16384] owner ref check failed [30425088 16384] ERROR: errors found in extent allocation tree or chunk allocation [3/7] checking free space cache [4/7] checking fs roots [5/7] checking only csums items (without verifying data) [6/7] checking root refs [7/7] checking quota groups skipped (not enabled on this FS) found 212992 bytes used, error(s) found total csum bytes: 0 total tree bytes: 131072 total fs tree bytes: 32768 total extent tree bytes: 16384 btree space waste bytes: 124669 file data blocks allocated: 65536 referenced 65536 So fix this by freeing the metadata extent if btrfs_insert_root() returns an error. CC: stable@vger.kernel.org # 4.4+ Signed-off-by: Filipe Manana <fdmanana@suse.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2021-04-19btrfs: handle remount to no compress during compressionQu Wenruo
[BUG] When running btrfs/071 with inode_need_compress() removed from compress_file_range(), we got the following crash: BUG: kernel NULL pointer dereference, address: 0000000000000018 #PF: supervisor read access in kernel mode #PF: error_code(0x0000) - not-present page Workqueue: btrfs-delalloc btrfs_work_helper [btrfs] RIP: 0010:compress_file_range+0x476/0x7b0 [btrfs] Call Trace: ? submit_compressed_extents+0x450/0x450 [btrfs] async_cow_start+0x16/0x40 [btrfs] btrfs_work_helper+0xf2/0x3e0 [btrfs] process_one_work+0x278/0x5e0 worker_thread+0x55/0x400 ? process_one_work+0x5e0/0x5e0 kthread+0x168/0x190 ? kthread_create_worker_on_cpu+0x70/0x70 ret_from_fork+0x22/0x30 ---[ end trace 65faf4eae941fa7d ]--- This is already after the patch "btrfs: inode: fix NULL pointer dereference if inode doesn't need compression." [CAUSE] @pages is firstly created by kcalloc() in compress_file_extent(): pages = kcalloc(nr_pages, sizeof(struct page *), GFP_NOFS); Then passed to btrfs_compress_pages() to be utilized there: ret = btrfs_compress_pages(... pages, &nr_pages, ...); btrfs_compress_pages() will initialize each page as output, in zlib_compress_pages() we have: pages[nr_pages] = out_page; nr_pages++; Normally this is completely fine, but there is a special case which is in btrfs_compress_pages() itself: switch (type) { default: return -E2BIG; } In this case, we didn't modify @pages nor @out_pages, leaving them untouched, then when we cleanup pages, the we can hit NULL pointer dereference again: if (pages) { for (i = 0; i < nr_pages; i++) { WARN_ON(pages[i]->mapping); put_page(pages[i]); } ... } Since pages[i] are all initialized to zero, and btrfs_compress_pages() doesn't change them at all, accessing pages[i]->mapping would lead to NULL pointer dereference. This is not possible for current kernel, as we check inode_need_compress() before doing pages allocation. But if we're going to remove that inode_need_compress() in compress_file_extent(), then it's going to be a problem. [FIX] When btrfs_compress_pages() hits its default case, modify @out_pages to 0 to prevent such problem from happening. Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=212331 CC: stable@vger.kernel.org # 5.10+ Reviewed-by: Josef Bacik <josef@toxicpanda.com> Signed-off-by: Qu Wenruo <wqu@suse.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2021-04-19btrfs: zoned: fail mount if the device does not support zone appendJohannes Thumshirn
For zoned btrfs, zone append is mandatory to write to a sequential write only zone, otherwise parallel writes to the same zone could result in unaligned write errors. If a zoned block device does not support zone append (e.g. a dm-crypt zoned device using a non-NULL IV cypher), fail to mount. CC: stable@vger.kernel.org # 5.12 Signed-off-by: Johannes Thumshirn <johannes.thumshirn@wdc.com> Signed-off-by: Damien Le Moal <damien.lemoal@wdc.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2021-04-19btrfs: fix race between transaction aborts and fsyncs leading to use-after-freeFilipe Manana
There is a race between a task aborting a transaction during a commit, a task doing an fsync and the transaction kthread, which leads to an use-after-free of the log root tree. When this happens, it results in a stack trace like the following: BTRFS info (device dm-0): forced readonly BTRFS warning (device dm-0): Skipping commit of aborted transaction. BTRFS: error (device dm-0) in cleanup_transaction:1958: errno=-5 IO failure BTRFS warning (device dm-0): lost page write due to IO error on /dev/mapper/error-test (-5) BTRFS warning (device dm-0): Skipping commit of aborted transaction. BTRFS warning (device dm-0): direct IO failed ino 261 rw 0,0 sector 0xa4e8 len 4096 err no 10 BTRFS error (device dm-0): error writing primary super block to device 1 BTRFS warning (device dm-0): direct IO failed ino 261 rw 0,0 sector 0x12e000 len 4096 err no 10 BTRFS warning (device dm-0): direct IO failed ino 261 rw 0,0 sector 0x12e008 len 4096 err no 10 BTRFS warning (device dm-0): direct IO failed ino 261 rw 0,0 sector 0x12e010 len 4096 err no 10 BTRFS: error (device dm-0) in write_all_supers:4110: errno=-5 IO failure (1 errors while writing supers) BTRFS: error (device dm-0) in btrfs_sync_log:3308: errno=-5 IO failure general protection fault, probably for non-canonical address 0x6b6b6b6b6b6b6b68: 0000 [#1] PREEMPT SMP DEBUG_PAGEALLOC PTI CPU: 2 PID: 2458471 Comm: fsstress Not tainted 5.12.0-rc5-btrfs-next-84 #1 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.14.0-0-g155821a1990b-prebuilt.qemu.org 04/01/2014 RIP: 0010:__mutex_lock+0x139/0xa40 Code: c0 74 19 (...) RSP: 0018:ffff9f18830d7b00 EFLAGS: 00010202 RAX: 6b6b6b6b6b6b6b68 RBX: 0000000000000001 RCX: 0000000000000002 RDX: ffffffffb9c54d13 RSI: 0000000000000000 RDI: 0000000000000000 RBP: ffff9f18830d7bc0 R08: 0000000000000000 R09: 0000000000000000 R10: ffff9f18830d7be0 R11: 0000000000000001 R12: ffff8c6cd199c040 R13: ffff8c6c95821358 R14: 00000000fffffffb R15: ffff8c6cbcf01358 FS: 00007fa9140c2b80(0000) GS:ffff8c6fac600000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fa913d52000 CR3: 000000013d2b4003 CR4: 0000000000370ee0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: ? __btrfs_handle_fs_error+0xde/0x146 [btrfs] ? btrfs_sync_log+0x7c1/0xf20 [btrfs] ? btrfs_sync_log+0x7c1/0xf20 [btrfs] btrfs_sync_log+0x7c1/0xf20 [btrfs] btrfs_sync_file+0x40c/0x580 [btrfs] do_fsync+0x38/0x70 __x64_sys_fsync+0x10/0x20 do_syscall_64+0x33/0x80 entry_SYSCALL_64_after_hwframe+0x44/0xae RIP: 0033:0x7fa9142a55c3 Code: 8b 15 09 (...) RSP: 002b:00007fff26278d48 EFLAGS: 00000246 ORIG_RAX: 000000000000004a RAX: ffffffffffffffda RBX: 0000563c83cb4560 RCX: 00007fa9142a55c3 RDX: 00007fff26278cb0 RSI: 00007fff26278cb0 RDI: 0000000000000005 RBP: 0000000000000005 R08: 0000000000000001 R09: 00007fff26278d5c R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000340 R13: 00007fff26278de0 R14: 00007fff26278d96 R15: 0000563c83ca57c0 Modules linked in: btrfs dm_zero dm_snapshot dm_thin_pool (...) ---[ end trace ee2f1b19327d791d ]--- The steps that lead to this crash are the following: 1) We are at transaction N; 2) We have two tasks with a transaction handle attached to transaction N. Task A and Task B. Task B is doing an fsync; 3) Task B is at btrfs_sync_log(), and has saved fs_info->log_root_tree into a local variable named 'log_root_tree' at the top of btrfs_sync_log(). Task B is about to call write_all_supers(), but before that... 4) Task A calls btrfs_commit_transaction(), and after it sets the transaction state to TRANS_STATE_COMMIT_START, an error happens before it waits for the transaction's 'num_writers' counter to reach a value of 1 (no one else attached to the transaction), so it jumps to the label "cleanup_transaction"; 5) Task A then calls cleanup_transaction(), where it aborts the transaction, setting BTRFS_FS_STATE_TRANS_ABORTED on fs_info->fs_state, setting the ->aborted field of the transaction and the handle to an errno value and also setting BTRFS_FS_STATE_ERROR on fs_info->fs_state. After that, at cleanup_transaction(), it deletes the transaction from the list of transactions (fs_info->trans_list), sets the transaction to the state TRANS_STATE_COMMIT_DOING and then waits for the number of writers to go down to 1, as it's currently 2 (1 for task A and 1 for task B); 6) The transaction kthread is running and sees that BTRFS_FS_STATE_ERROR is set in fs_info->fs_state, so it calls btrfs_cleanup_transaction(). There it sees the list fs_info->trans_list is empty, and then proceeds into calling btrfs_drop_all_logs(), which frees the log root tree with a call to btrfs_free_log_root_tree(); 7) Task B calls write_all_supers() and, shortly after, under the label 'out_wake_log_root', it deferences the pointer stored in 'log_root_tree', which was already freed in the previous step by the transaction kthread. This results in a use-after-free leading to a crash. Fix this by deleting the transaction from the list of transactions at cleanup_transaction() only after setting the transaction state to TRANS_STATE_COMMIT_DOING and waiting for all existing tasks that are attached to the transaction to release their transaction handles. This makes the transaction kthread wait for all the tasks attached to the transaction to be done with the transaction before dropping the log roots and doing other cleanups. Fixes: ef67963dac255b ("btrfs: drop logs when we've aborted a transaction") CC: stable@vger.kernel.org # 5.10+ Reviewed-by: Josef Bacik <josef@toxicpanda.com> Signed-off-by: Filipe Manana <fdmanana@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2021-04-19btrfs: introduce submit_eb_subpage() to submit a subpage metadata pageQu Wenruo
The new function, submit_eb_subpage(), will submit all the dirty extent buffers in the page. The major difference between submit_eb_page() and submit_eb_subpage() is: - How to grab extent buffer Now we use find_extent_buffer_nospinlock() other than using page::private. All other different handling is already done in functions like lock_extent_buffer_for_io() and write_one_eb(). Signed-off-by: Qu Wenruo <wqu@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2021-04-19btrfs: make lock_extent_buffer_for_io() to be subpage compatibleQu Wenruo
For subpage metadata, we don't use page locking at all. So just skip the page locking part for subpage. The rest of the function can be reused. Signed-off-by: Qu Wenruo <wqu@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2021-04-19btrfs: introduce write_one_subpage_eb() functionQu Wenruo
The new function, write_one_subpage_eb(), as a subroutine for subpage metadata write, will handle the extent buffer bio submission. The major differences between the new write_one_subpage_eb() and write_one_eb() is: - No page locking When entering write_one_subpage_eb() the page is no longer locked. We only lock the page for its status update, and unlock immediately. Now we completely rely on extent io tree locking. - Extra bitmap update along with page status update Now page dirty and writeback is controlled by btrfs_subpage::dirty_bitmap and btrfs_subpage::writeback_bitmap. They both follow the schema that any sector is dirty/writeback, then the full page gets dirty/writeback. - When to update the nr_written number Now we take a shortcut, if we have cleared the last dirty bit of the page, we update nr_written. This is not completely perfect, but should emulate the old behavior well enough. Signed-off-by: Qu Wenruo <wqu@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2021-04-19btrfs: introduce end_bio_subpage_eb_writepage() functionQu Wenruo
The new function, end_bio_subpage_eb_writepage(), will handle the metadata writeback endio. The major differences involved are: - How to grab extent buffer Now page::private is a pointer to btrfs_subpage, we can no longer grab extent buffer directly. Thus we need to use the bv_offset to locate the extent buffer manually and iterate through the whole range. - Use btrfs_subpage_end_writeback() caller This helper will handle the subpage writeback for us. Since this function is executed under endio context, when grabbing extent buffers it can't grab eb->refs_lock as that lock is not designed to be grabbed under hardirq context. So here introduce a helper, find_extent_buffer_nolock(), for such situation, and convert find_extent_buffer() to use that helper. Signed-off-by: Qu Wenruo <wqu@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2021-04-19btrfs: check return value of btrfs_commit_transaction in relocationJosef Bacik
There are a few places where we don't check the return value of btrfs_commit_transaction in relocation.c. Thankfully all these places have straightforward error handling, so simply change all of the sites at once. Reviewed-by: Qu Wenruo <wqu@suse.com> Signed-off-by: Josef Bacik <josef@toxicpanda.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2021-04-19btrfs: do proper error handling in merge_reloc_rootsJosef Bacik
We have a BUG_ON() if we get an error back from btrfs_get_fs_root(). This honestly should never fail, as at this point we have a solid coordination of fs root to reloc root, and these roots will all be in memory. But in the name of killing BUG_ON()'s remove these and handle the error condition properly, ASSERT()'ing for developers. Signed-off-by: Josef Bacik <josef@toxicpanda.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2021-04-19btrfs: handle extent corruption with select_one_root properlyJosef Bacik
In corruption cases we could have paths from a block up to no root at all, and thus we'll BUG_ON(!root) in select_one_root. Handle this by adding an ASSERT() for developers, and returning an error for normal users. Signed-off-by: Josef Bacik <josef@toxicpanda.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2021-04-19btrfs: cleanup error handling in prepare_to_mergeJosef Bacik
This probably can't happen even with a corrupt file system, because we would have failed much earlier on than here. However there's no reason we can't just check and bail out as appropriate, so do that and convert the correctness BUG_ON() to an ASSERT(). Reviewed-by: Qu Wenruo <wqu@suse.com> Signed-off-by: Josef Bacik <josef@toxicpanda.com> Reviewed-by: David Sterba <dsterba@suse.com> [ add comment ] Signed-off-by: David Sterba <dsterba@suse.com>
2021-04-19btrfs: do not panic in __add_reloc_rootJosef Bacik
If we have a duplicate entry for a reloc root then we could have fs corruption that resulted in a double allocation. Since this shouldn't happen unless there is corruption, add an ASSERT(ret != -EEXIST) to all of the callers of __add_reloc_root() to catch any logic mistakes for developers, otherwise normal error handling will happen for normal users. Signed-off-by: Josef Bacik <josef@toxicpanda.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2021-04-19btrfs: handle __add_reloc_root failures in btrfs_recover_relocationJosef Bacik
We can already handle errors appropriately from this function, deal with an error coming from __add_reloc_root appropriately. Reviewed-by: Qu Wenruo <wqu@suse.com> Signed-off-by: Josef Bacik <josef@toxicpanda.com> Reviewed-by: David Sterba <dsterba@suse.com> [ add comment ] Signed-off-by: David Sterba <dsterba@suse.com>
2021-04-19btrfs: do proper error handling in create_reloc_inodeJosef Bacik
We already handle some errors in this function, and the callers do the correct error handling, so clean up the rest of the function to do the appropriate error handling. There's a little extra work that needs to be done here, as we create the inode item before we create the orphan item. We could potentially add the orphan item, but if we failed to create the inode item we would have to abort the transaction. Instead add a helper to delete the inode item we created in the case that we're unable to look up the inode (this would likely be caused by an ENOMEM), which if it succeeds means we can avoid a transaction abort in this particular error case. Signed-off-by: Josef Bacik <josef@toxicpanda.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2021-04-19btrfs: remove the extent item sanity checks in relocate_block_groupJosef Bacik
These checks are all taken care of for us by the tree checker code: - the flags don't change or are updated consistently - the v0 extent item format is invalid and caught in many other places too Reviewed-by: Qu Wenruo <wqu@suse.com> Signed-off-by: Josef Bacik <josef@toxicpanda.com> Reviewed-by: David Sterba <dsterba@suse.com> [ update changelog ] Signed-off-by: David Sterba <dsterba@suse.com>
2021-04-19btrfs: tree-checker: check for BTRFS_BLOCK_FLAG_FULL_BACKREF being set ↵Josef Bacik
improperly We need to validate that a data extent item does not have the FULL_BACKREF flag set on its flags. Reviewed-by: Qu Wenruo <wqu@suse.com> Signed-off-by: Josef Bacik <josef@toxicpanda.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2021-04-19btrfs: handle extent reference errors in do_relocationJosef Bacik
We can already deal with errors appropriately from do_relocation, simply handle any errors that come from changing the refs at this point cleanly. We have to abort the transaction if we fail here as we've modified metadata at this point. Signed-off-by: Josef Bacik <josef@toxicpanda.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2021-04-19btrfs: handle errors in reference count manipulation in replace_pathJosef Bacik
If any of the reference count manipulation stuff fails in replace_path we need to abort the transaction, as we've modified the blocks already. We can simply break at this point and everything will be cleaned up. Reviewed-by: Qu Wenruo <wqu@suse.com> Signed-off-by: Josef Bacik <josef@toxicpanda.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2021-04-19btrfs: handle btrfs_search_slot failure in replace_pathJosef Bacik
The search can fail for various reasons, in case of errors there's no cleanup to be done so we can pass the error to the caller, adjusting for the case where the key is not found and search slot returns 1. Reviewed-by: Qu Wenruo <wqu@suse.com> Signed-off-by: Josef Bacik <josef@toxicpanda.com> Reviewed-by: David Sterba <dsterba@suse.com> [ update changelog ] Signed-off-by: David Sterba <dsterba@suse.com>
2021-04-19btrfs: handle btrfs_cow_block errors in replace_pathJosef Bacik
If we error out COWing the root node when doing a replace_path then we simply unlock and free the buffer and return the error. Reviewed-by: Qu Wenruo <wqu@suse.com> Signed-off-by: Josef Bacik <josef@toxicpanda.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2021-04-19btrfs: convert logic BUG_ON()'s in replace_path to ASSERT()'sJosef Bacik
A few BUG_ON()'s in replace_path are purely to keep us from making logical mistakes, so replace them with ASSERT()'s. Reviewed-by: Qu Wenruo <wqu@suse.com> Signed-off-by: Josef Bacik <josef@toxicpanda.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2021-04-19btrfs: do proper error handling in btrfs_update_reloc_rootJosef Bacik
We call btrfs_update_root in btrfs_update_reloc_root, which can fail for all sorts of reasons, including IO errors. Instead of panicing the box lets return the error, now that all callers properly handle those errors. Reviewed-by: Qu Wenruo <wqu@suse.com> Signed-off-by: Josef Bacik <josef@toxicpanda.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2021-04-19btrfs: handle btrfs_update_reloc_root failure in prepare_to_mergeJosef Bacik
btrfs_update_reloc_root will will return errors in the future, so handle an error properly in prepare_to_merge. Signed-off-by: Josef Bacik <josef@toxicpanda.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2021-04-19btrfs: handle btrfs_update_reloc_root failure in insert_dirty_subvolJosef Bacik
btrfs_update_reloc_root will will return errors in the future, so handle the error properly in insert_dirty_subvol. Signed-off-by: Josef Bacik <josef@toxicpanda.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2021-04-19btrfs: change insert_dirty_subvol to return errorsJosef Bacik
This will be able to return errors in the future, so change it to return an error and handle the errors appropriately. Signed-off-by: Josef Bacik <josef@toxicpanda.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2021-04-19btrfs: handle btrfs_update_reloc_root failure in commit_fs_rootsJosef Bacik
btrfs_update_reloc_root will will return errors in the future, so handle the error properly in commit_fs_roots. Reviewed-by: Qu Wenruo <wqu@suse.com> Signed-off-by: Josef Bacik <josef@toxicpanda.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2021-04-19btrfs: validate root::reloc_root after recording root in transJosef Bacik
If we fail to setup a root->reloc_root in a different thread that path will error out, however it still leaves root->reloc_root NULL but would still appear set up in the transaction. Subsequent calls to btrfs_record_root_in_transaction would succeed without attempting to create the reloc root, as the transid has already been updated. Handle this case by making sure we have a root->reloc_root set after a btrfs_record_root_in_transaction call so we don't end up dereferencing a NULL pointer. Reported-by: Zygo Blaxell <ce3g8jdj@umail.furryterror.org> Signed-off-by: Josef Bacik <josef@toxicpanda.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2021-04-19btrfs: do proper error handling in create_reloc_rootJosef Bacik
We do memory allocations here, read blocks from disk, all sorts of operations that could easily fail at any given point. Instead of panicing the box, simply return the error back up the chain, all callers at this point have proper error handling. Signed-off-by: Josef Bacik <josef@toxicpanda.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2021-04-19btrfs: have proper error handling in btrfs_init_reloc_rootJosef Bacik
create_reloc_root will return errors in the future, and __add_reloc_root can return ENOMEM or EEXIST, so handle these errors properly. Signed-off-by: Josef Bacik <josef@toxicpanda.com> Reviewed-by: David Sterba <dsterba@suse.com> [ add comment ] Signed-off-by: David Sterba <dsterba@suse.com>
2021-04-19btrfs: return an error from btrfs_record_root_in_transJosef Bacik
We can create a reloc root when we record the root in the trans, which can fail for all sorts of different reasons. Propagate this error up the chain of callers. Future patches will fix the callers of btrfs_record_root_in_trans() to handle the error. Reviewed-by: Qu Wenruo <wqu@suse.com> Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com> Signed-off-by: Josef Bacik <josef@toxicpanda.com> Signed-off-by: David Sterba <dsterba@suse.com>