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* Merge tag 'for-5.5-rc8-tag' of ↵Linus Torvalds2020-01-252-9/+29
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux Pull btrfs fix from David Sterba: "Here's a last minute fix for a regression introduced in this development cycle. There's a small chance of a silent corruption when device replace and NOCOW data writes happen at the same time in one block group. Metadata or COW data writes are unaffected. The extra fixup patch is there to silence an unnecessary warning" * tag 'for-5.5-rc8-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux: btrfs: dev-replace: remove warning for unknown return codes when finished btrfs: scrub: Require mandatory block group RO for dev-replace
| * btrfs: dev-replace: remove warning for unknown return codes when finishedDavid Sterba2020-01-251-4/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The fstests btrfs/011 triggered a warning at the end of device replace, [ 1891.998975] BTRFS warning (device vdd): failed setting block group ro: -28 [ 1892.038338] BTRFS error (device vdd): btrfs_scrub_dev(/dev/vdd, 1, /dev/vdb) failed -28 [ 1892.059993] ------------[ cut here ]------------ [ 1892.063032] WARNING: CPU: 2 PID: 2244 at fs/btrfs/dev-replace.c:506 btrfs_dev_replace_start.cold+0xf9/0x140 [btrfs] [ 1892.074346] CPU: 2 PID: 2244 Comm: btrfs Not tainted 5.5.0-rc7-default+ #942 [ 1892.079956] RIP: 0010:btrfs_dev_replace_start.cold+0xf9/0x140 [btrfs] [ 1892.096576] RSP: 0018:ffffbb58c7b3fd10 EFLAGS: 00010286 [ 1892.098311] RAX: 00000000ffffffe4 RBX: 0000000000000001 RCX: 8888888888888889 [ 1892.100342] RDX: 0000000000000001 RSI: ffff9e889645f5d8 RDI: ffffffff92821080 [ 1892.102291] RBP: ffff9e889645c000 R08: 000001b8878fe1f6 R09: 0000000000000000 [ 1892.104239] R10: ffffbb58c7b3fd08 R11: 0000000000000000 R12: ffff9e88a0017000 [ 1892.106434] R13: ffff9e889645f608 R14: ffff9e88794e1000 R15: ffff9e88a07b5200 [ 1892.108642] FS: 00007fcaed3f18c0(0000) GS:ffff9e88bda00000(0000) knlGS:0000000000000000 [ 1892.111558] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 1892.113492] CR2: 00007f52509ff420 CR3: 00000000603dd002 CR4: 0000000000160ee0 [ 1892.115814] Call Trace: [ 1892.116896] btrfs_dev_replace_by_ioctl+0x35/0x60 [btrfs] [ 1892.118962] btrfs_ioctl+0x1d62/0x2550 [btrfs] caused by the previous patch ("btrfs: scrub: Require mandatory block group RO for dev-replace"). Hitting ENOSPC is possible and could happen when the block group is set read-only, preventing NOCOW writes to the area that's being accessed by dev-replace. This has happend with scratch devices of size 12G but not with 5G and 20G, so this is depends on timing and other activity on the filesystem. The whole replace operation is restartable, the space state should be examined by the user in any case. The error code is propagated back to the ioctl caller so the kernel warning is causing false alerts. Signed-off-by: David Sterba <dsterba@suse.com>
| * btrfs: scrub: Require mandatory block group RO for dev-replaceQu Wenruo2020-01-241-5/+28
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | [BUG] For dev-replace test cases with fsstress, like btrfs/06[45] btrfs/071, looped runs can lead to random failure, where scrub finds csum error. The possibility is not high, around 1/20 to 1/100, but it's causing data corruption. The bug is observable after commit b12de52896c0 ("btrfs: scrub: Don't check free space before marking a block group RO") [CAUSE] Dev-replace has two source of writes: - Write duplication All writes to source device will also be duplicated to target device. Content: Not yet persisted data/meta - Scrub copy Dev-replace reused scrub code to iterate through existing extents, and copy the verified data to target device. Content: Previously persisted data and metadata The difference in contents makes the following race possible: Regular Writer | Dev-replace ----------------------------------------------------------------- ^ | | Preallocate one data extent | | at bytenr X, len 1M | v | ^ Commit transaction | | Now extent [X, X+1M) is in | v commit root | ================== Dev replace starts ========================= | ^ | | Scrub extent [X, X+1M) | | Read [X, X+1M) | | (The content are mostly garbage | | since it's preallocated) ^ | v | Write back happens for | | extent [X, X+512K) | | New data writes to both | | source and target dev. | v | | ^ | | Scrub writes back extent [X, X+1M) | | to target device. | | This will over write the new data in | | [X, X+512K) | v This race can only happen for nocow writes. Thus metadata and data cow writes are safe, as COW will never overwrite extents of previous transaction (in commit root). This behavior can be confirmed by disabling all fallocate related calls in fsstress (*), then all related tests can pass a 2000 run loop. *: FSSTRESS_AVOID="-f fallocate=0 -f allocsp=0 -f zero=0 -f insert=0 \ -f collapse=0 -f punch=0 -f resvsp=0" I didn't expect resvsp ioctl will fallback to fallocate in VFS... [FIX] Make dev-replace to require mandatory block group RO, and wait for current nocow writes before calling scrub_chunk(). This patch will mostly revert commit 76a8efa171bf ("btrfs: Continue replace when set_block_ro failed") for dev-replace path. The side effect is, dev-replace can be more strict on avaialble space, but definitely worth to avoid data corruption. Reported-by: Filipe Manana <fdmanana@suse.com> Fixes: 76a8efa171bf ("btrfs: Continue replace when set_block_ro failed") Fixes: b12de52896c0 ("btrfs: scrub: Don't check free space before marking a block group RO") Reviewed-by: Filipe Manana <fdmanana@suse.com> Signed-off-by: Qu Wenruo <wqu@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
* | Merge tag 'for-5.5-rc6-tag' of ↵Linus Torvalds2020-01-176-46/+114
|\| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux Pull btrfs fixes from David Sterba: "A few more fixes that have been in the works during last twp weeks. All have a user visible effect and are stable material: - scrub: properly update progress after calling cancel ioctl, calling 'resume' would start from the beginning otherwise - fix subvolume reference removal, after moving out of the original path the reference is not recognized and will lead to transaction abort - fix reloc root lifetime checks, could lead to crashes when there's subvolume cleaning running in parallel - fix memory leak when quotas get disabled in the middle of extent accounting - fix transaction abort in case of balance being started on degraded mount on eg. RAID1" * tag 'for-5.5-rc6-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux: btrfs: check rw_devices, not num_devices for balance Btrfs: always copy scrub arguments back to user space btrfs: relocation: fix reloc_root lifespan and access btrfs: fix memory leak in qgroup accounting btrfs: do not delete mismatched root refs btrfs: fix invalid removal of root ref btrfs: rework arguments of btrfs_unlink_subvol
| * btrfs: check rw_devices, not num_devices for balanceJosef Bacik2020-01-171-1/+5
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The fstest btrfs/154 reports [ 8675.381709] BTRFS: Transaction aborted (error -28) [ 8675.383302] WARNING: CPU: 1 PID: 31900 at fs/btrfs/block-group.c:2038 btrfs_create_pending_block_groups+0x1e0/0x1f0 [btrfs] [ 8675.390925] CPU: 1 PID: 31900 Comm: btrfs Not tainted 5.5.0-rc6-default+ #935 [ 8675.392780] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.12.0-59-gc9ba527-rebuilt.opensuse.org 04/01/2014 [ 8675.395452] RIP: 0010:btrfs_create_pending_block_groups+0x1e0/0x1f0 [btrfs] [ 8675.402672] RSP: 0018:ffffb2090888fb00 EFLAGS: 00010286 [ 8675.404413] RAX: 0000000000000000 RBX: ffff92026dfa91c8 RCX: 0000000000000001 [ 8675.406609] RDX: 0000000000000000 RSI: ffffffff8e100899 RDI: ffffffff8e100971 [ 8675.408775] RBP: ffff920247c61660 R08: 0000000000000000 R09: 0000000000000000 [ 8675.410978] R10: 0000000000000000 R11: 0000000000000000 R12: 00000000ffffffe4 [ 8675.412647] R13: ffff92026db74000 R14: ffff920247c616b8 R15: ffff92026dfbc000 [ 8675.413994] FS: 00007fd5e57248c0(0000) GS:ffff92027d800000(0000) knlGS:0000000000000000 [ 8675.416146] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 8675.417833] CR2: 0000564aa51682d8 CR3: 000000006dcbc004 CR4: 0000000000160ee0 [ 8675.419801] Call Trace: [ 8675.420742] btrfs_start_dirty_block_groups+0x355/0x480 [btrfs] [ 8675.422600] btrfs_commit_transaction+0xc8/0xaf0 [btrfs] [ 8675.424335] reset_balance_state+0x14a/0x190 [btrfs] [ 8675.425824] btrfs_balance.cold+0xe7/0x154 [btrfs] [ 8675.427313] ? kmem_cache_alloc_trace+0x235/0x2c0 [ 8675.428663] btrfs_ioctl_balance+0x298/0x350 [btrfs] [ 8675.430285] btrfs_ioctl+0x466/0x2550 [btrfs] [ 8675.431788] ? mem_cgroup_charge_statistics+0x51/0xf0 [ 8675.433487] ? mem_cgroup_commit_charge+0x56/0x400 [ 8675.435122] ? do_raw_spin_unlock+0x4b/0xc0 [ 8675.436618] ? _raw_spin_unlock+0x1f/0x30 [ 8675.438093] ? __handle_mm_fault+0x499/0x740 [ 8675.439619] ? do_vfs_ioctl+0x56e/0x770 [ 8675.441034] do_vfs_ioctl+0x56e/0x770 [ 8675.442411] ksys_ioctl+0x3a/0x70 [ 8675.443718] ? trace_hardirqs_off_thunk+0x1a/0x1c [ 8675.445333] __x64_sys_ioctl+0x16/0x20 [ 8675.446705] do_syscall_64+0x50/0x210 [ 8675.448059] entry_SYSCALL_64_after_hwframe+0x49/0xbe [ 8675.479187] BTRFS: error (device vdb) in btrfs_create_pending_block_groups:2038: errno=-28 No space left We now use btrfs_can_overcommit() to see if we can flip a block group read only. Before this would fail because we weren't taking into account the usable un-allocated space for allocating chunks. With my patches we were allowed to do the balance, which is technically correct. The test is trying to start balance on degraded mount. So now we're trying to allocate a chunk and cannot because we want to allocate a RAID1 chunk, but there's only 1 device that's available for usage. This results in an ENOSPC. But we shouldn't even be making it this far, we don't have enough devices to restripe. The problem is we're using btrfs_num_devices(), that also includes missing devices. That's not actually what we want, we need to use rw_devices. The chunk_mutex is not needed here, rw_devices changes only in device add, remove or replace, all are excluded by EXCL_OP mechanism. Fixes: e4d8ec0f65b9 ("Btrfs: implement online profile changing") CC: stable@vger.kernel.org # 4.4+ Signed-off-by: Josef Bacik <josef@toxicpanda.com> Reviewed-by: David Sterba <dsterba@suse.com> [ add stacktrace, update changelog, drop chunk_mutex ] Signed-off-by: David Sterba <dsterba@suse.com>
| * Btrfs: always copy scrub arguments back to user spaceFilipe Manana2020-01-171-1/+13
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | If scrub returns an error we are not copying back the scrub arguments structure to user space. This prevents user space to know how much progress scrub has done if an error happened - this includes -ECANCELED which is returned when users ask for scrub to stop. A particular use case, which is used in btrfs-progs, is to resume scrub after it is canceled, in that case it relies on checking the progress from the scrub arguments structure and then use that progress in a call to resume scrub. So fix this by always copying the scrub arguments structure to user space, overwriting the value returned to user space with -EFAULT only if copying the structure failed to let user space know that either that copying did not happen, and therefore the structure is stale, or it happened partially and the structure is probably not valid and corrupt due to the partial copy. Reported-by: Graham Cobb <g.btrfs@cobb.uk.net> Link: https://lore.kernel.org/linux-btrfs/d0a97688-78be-08de-ca7d-bcb4c7fb397e@cobb.uk.net/ Fixes: 06fe39ab15a6a4 ("Btrfs: do not overwrite scrub error with fault error in scrub ioctl") CC: stable@vger.kernel.org # 5.1+ Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com> Reviewed-by: Qu Wenruo <wqu@suse.com> Tested-by: Graham Cobb <g.btrfs@cobb.uk.net> Signed-off-by: Filipe Manana <fdmanana@suse.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
| * btrfs: relocation: fix reloc_root lifespan and accessQu Wenruo2020-01-131-5/+46
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | [BUG] There are several different KASAN reports for balance + snapshot workloads. Involved call paths include: should_ignore_root+0x54/0xb0 [btrfs] build_backref_tree+0x11af/0x2280 [btrfs] relocate_tree_blocks+0x391/0xb80 [btrfs] relocate_block_group+0x3e5/0xa00 [btrfs] btrfs_relocate_block_group+0x240/0x4d0 [btrfs] btrfs_relocate_chunk+0x53/0xf0 [btrfs] btrfs_balance+0xc91/0x1840 [btrfs] btrfs_ioctl_balance+0x416/0x4e0 [btrfs] btrfs_ioctl+0x8af/0x3e60 [btrfs] do_vfs_ioctl+0x831/0xb10 create_reloc_root+0x9f/0x460 [btrfs] btrfs_reloc_post_snapshot+0xff/0x6c0 [btrfs] create_pending_snapshot+0xa9b/0x15f0 [btrfs] create_pending_snapshots+0x111/0x140 [btrfs] btrfs_commit_transaction+0x7a6/0x1360 [btrfs] btrfs_mksubvol+0x915/0x960 [btrfs] btrfs_ioctl_snap_create_transid+0x1d5/0x1e0 [btrfs] btrfs_ioctl_snap_create_v2+0x1d3/0x270 [btrfs] btrfs_ioctl+0x241b/0x3e60 [btrfs] do_vfs_ioctl+0x831/0xb10 btrfs_reloc_pre_snapshot+0x85/0xc0 [btrfs] create_pending_snapshot+0x209/0x15f0 [btrfs] create_pending_snapshots+0x111/0x140 [btrfs] btrfs_commit_transaction+0x7a6/0x1360 [btrfs] btrfs_mksubvol+0x915/0x960 [btrfs] btrfs_ioctl_snap_create_transid+0x1d5/0x1e0 [btrfs] btrfs_ioctl_snap_create_v2+0x1d3/0x270 [btrfs] btrfs_ioctl+0x241b/0x3e60 [btrfs] do_vfs_ioctl+0x831/0xb10 [CAUSE] All these call sites are only relying on root->reloc_root, which can undergo btrfs_drop_snapshot(), and since we don't have real refcount based protection to reloc roots, we can reach already dropped reloc root, triggering KASAN. [FIX] To avoid such access to unstable root->reloc_root, we should check BTRFS_ROOT_DEAD_RELOC_TREE bit first. This patch introduces wrappers that provide the correct way to check the bit with memory barriers protection. Most callers don't distinguish merged reloc tree and no reloc tree. The only exception is should_ignore_root(), as merged reloc tree can be ignored, while no reloc tree shouldn't. [CRITICAL SECTION ANALYSIS] Although test_bit()/set_bit()/clear_bit() doesn't imply a barrier, the DEAD_RELOC_TREE bit has extra help from transaction as a higher level barrier, the lifespan of root::reloc_root and DEAD_RELOC_TREE bit are: NULL: reloc_root is NULL PTR: reloc_root is not NULL 0: DEAD_RELOC_ROOT bit not set DEAD: DEAD_RELOC_ROOT bit set (NULL, 0) Initial state __ | /\ Section A btrfs_init_reloc_root() \/ | __ (PTR, 0) reloc_root initialized /\ | | btrfs_update_reloc_root() | Section B | | (PTR, DEAD) reloc_root has been merged \/ | __ === btrfs_commit_transaction() ==================== | /\ clean_dirty_subvols() | | | Section C (NULL, DEAD) reloc_root cleanup starts \/ | __ btrfs_drop_snapshot() /\ | | Section D (NULL, 0) Back to initial state \/ Every have_reloc_root() or test_bit(DEAD_RELOC_ROOT) caller holds transaction handle, so none of such caller can cross transaction boundary. In Section A, every caller just found no DEAD bit, and grab reloc_root. In the cross section A-B, caller may get no DEAD bit, but since reloc_root is still completely valid thus accessing reloc_root is completely safe. No test_bit() caller can cross the boundary of Section B and Section C. In Section C, every caller found the DEAD bit, so no one will access reloc_root. In the cross section C-D, either caller gets the DEAD bit set, avoiding access reloc_root no matter if it's safe or not. Or caller get the DEAD bit cleared, then access reloc_root, which is already NULL, nothing will be wrong. The memory write barriers are between the reloc_root updates and bit set/clear, the pairing read side is before test_bit. Reported-by: Zygo Blaxell <ce3g8jdj@umail.furryterror.org> Fixes: d2311e698578 ("btrfs: relocation: Delay reloc tree deletion after merge_reloc_roots") CC: stable@vger.kernel.org # 5.4+ Reviewed-by: Josef Bacik <josef@toxicpanda.com> Signed-off-by: Qu Wenruo <wqu@suse.com> Reviewed-by: David Sterba <dsterba@suse.com> [ barriers ] Signed-off-by: David Sterba <dsterba@suse.com>
| * btrfs: fix memory leak in qgroup accountingJohannes Thumshirn2020-01-081-1/+5
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | When running xfstests on the current btrfs I get the following splat from kmemleak: unreferenced object 0xffff88821b2404e0 (size 32): comm "kworker/u4:7", pid 26663, jiffies 4295283698 (age 8.776s) hex dump (first 32 bytes): 01 00 00 00 00 00 00 00 10 ff fd 26 82 88 ff ff ...........&.... 10 ff fd 26 82 88 ff ff 20 ff fd 26 82 88 ff ff ...&.... ..&.... backtrace: [<00000000f94fd43f>] ulist_alloc+0x25/0x60 [btrfs] [<00000000fd023d99>] btrfs_find_all_roots_safe+0x41/0x100 [btrfs] [<000000008f17bd32>] btrfs_find_all_roots+0x52/0x70 [btrfs] [<00000000b7660afb>] btrfs_qgroup_rescan_worker+0x343/0x680 [btrfs] [<0000000058e66778>] btrfs_work_helper+0xac/0x1e0 [btrfs] [<00000000f0188930>] process_one_work+0x1cf/0x350 [<00000000af5f2f8e>] worker_thread+0x28/0x3c0 [<00000000b55a1add>] kthread+0x109/0x120 [<00000000f88cbd17>] ret_from_fork+0x35/0x40 This corresponds to: (gdb) l *(btrfs_find_all_roots_safe+0x41) 0x8d7e1 is in btrfs_find_all_roots_safe (fs/btrfs/backref.c:1413). 1408 1409 tmp = ulist_alloc(GFP_NOFS); 1410 if (!tmp) 1411 return -ENOMEM; 1412 *roots = ulist_alloc(GFP_NOFS); 1413 if (!*roots) { 1414 ulist_free(tmp); 1415 return -ENOMEM; 1416 } 1417 Following the lifetime of the allocated 'roots' ulist, it gets freed again in btrfs_qgroup_account_extent(). But this does not happen if the function is called with the 'BTRFS_FS_QUOTA_ENABLED' flag cleared, then btrfs_qgroup_account_extent() does a short leave and directly returns. Instead of directly returning we should jump to the 'out_free' in order to free all resources as expected. CC: stable@vger.kernel.org # 4.14+ Reviewed-by: Qu Wenruo <wqu@suse.com> Signed-off-by: Johannes Thumshirn <johannes.thumshirn@wdc.com> [ add comment ] Signed-off-by: David Sterba <dsterba@suse.com>
| * btrfs: do not delete mismatched root refsJosef Bacik2020-01-081-4/+6
| | | | | | | | | | | | | | | | | | | | | | | | | | btrfs_del_root_ref() will simply WARN_ON() if the ref doesn't match in any way, and then continue to delete the reference. This shouldn't happen, we have these values because there's more to the reference than the original root and the sub root. If any of these checks fail, return -ENOENT. CC: stable@vger.kernel.org # 4.4+ Signed-off-by: Josef Bacik <josef@toxicpanda.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
| * btrfs: fix invalid removal of root refJosef Bacik2020-01-081-8/+19
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | If we have the following sequence of events btrfs sub create A btrfs sub create A/B btrfs sub snap A C mkdir C/foo mv A/B C/foo rm -rf * We will end up with a transaction abort. The reason for this is because we create a root ref for B pointing to A. When we create a snapshot of C we still have B in our tree, but because the root ref points to A and not C we will make it appear to be empty. The problem happens when we move B into C. This removes the root ref for B pointing to A and adds a ref of B pointing to C. When we rmdir C we'll see that we have a ref to our root and remove the root ref, despite not actually matching our reference name. Now btrfs_del_root_ref() allowing this to work is a bug as well, however we know that this inode does not actually point to a root ref in the first place, so we shouldn't be calling btrfs_del_root_ref() in the first place and instead simply look up our dir index for this item and do the rest of the removal. CC: stable@vger.kernel.org # 4.4+ Signed-off-by: Josef Bacik <josef@toxicpanda.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
| * btrfs: rework arguments of btrfs_unlink_subvolJosef Bacik2020-01-081-26/+20
| | | | | | | | | | | | | | | | | | | | | | | | | | | | btrfs_unlink_subvol takes the name of the dentry and the root objectid based on what kind of inode this is, either a real subvolume link or a empty one that we inherited as a snapshot. We need to fix how we unlink in the case for BTRFS_EMPTY_SUBVOL_DIR_OBJECTID in the future, so rework btrfs_unlink_subvol to just take the dentry and handle getting the right objectid given the type of inode this is. There is no functional change here, simply pushing the work into btrfs_unlink_subvol() proper. Signed-off-by: Josef Bacik <josef@toxicpanda.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
* | Merge tag 'for-5.5-rc4-tag' of ↵Linus Torvalds2020-01-032-4/+9
|\| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux Pull btrfs fixes from David Sterba: "A few fixes for btrfs: - blkcg accounting problem with compression that could stall writes - setting up blkcg bio for compression crashes due to NULL bdev pointer - fix possible infinite loop in writeback for nocow files (here possible means almost impossible, 13 things that need to happen to trigger it)" * tag 'for-5.5-rc4-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux: Btrfs: fix infinite loop during nocow writeback due to race btrfs: fix compressed write bio blkcg attribution btrfs: punt all bios created in btrfs_submit_compressed_write()
| * Btrfs: fix infinite loop during nocow writeback due to raceFilipe Manana2019-12-301-3/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | When starting writeback for a range that covers part of a preallocated extent, due to a race with writeback for another range that also covers another part of the same preallocated extent, we can end up in an infinite loop. Consider the following example where for inode 280 we have two dirty ranges: range A, from 294912 to 303103, 8192 bytes range B, from 348160 to 438271, 90112 bytes and we have the following file extent item layout for our inode: leaf 38895616 gen 24544 total ptrs 29 free space 13820 owner 5 (...) item 27 key (280 108 200704) itemoff 14598 itemsize 53 extent data disk bytenr 0 nr 0 type 1 (regular) extent data offset 0 nr 94208 ram 94208 item 28 key (280 108 294912) itemoff 14545 itemsize 53 extent data disk bytenr 10433052672 nr 81920 type 2 (prealloc) extent data offset 0 nr 81920 ram 81920 Then the following happens: 1) Writeback starts for range B (from 348160 to 438271), execution of run_delalloc_nocow() starts; 2) The first iteration of run_delalloc_nocow()'s whil loop leaves us at the extent item at slot 28, pointing to the prealloc extent item covering the range from 294912 to 376831. This extent covers part of our range; 3) An ordered extent is created against that extent, covering the file range from 348160 to 376831 (28672 bytes); 4) We adjust 'cur_offset' to 376832 and move on to the next iteration of the while loop; 5) The call to btrfs_lookup_file_extent() leaves us at the same leaf, pointing to slot 29, 1 slot after the last item (the extent item we processed in the previous iteration); 6) Because we are a slot beyond the last item, we call btrfs_next_leaf(), which releases the search path before doing a another search for the last key of the leaf (280 108 294912); 7) Right after btrfs_next_leaf() released the path, and before it did another search for the last key of the leaf, writeback for the range A (from 294912 to 303103) completes (it was previously started at some point); 8) Upon completion of the ordered extent for range A, the prealloc extent we previously found got split into two extent items, one covering the range from 294912 to 303103 (8192 bytes), with a type of regular extent (and no longer prealloc) and another covering the range from 303104 to 376831 (73728 bytes), with a type of prealloc and an offset of 8192 bytes. So our leaf now has the following layout: leaf 38895616 gen 24544 total ptrs 31 free space 13664 owner 5 (...) item 27 key (280 108 200704) itemoff 14598 itemsize 53 extent data disk bytenr 0 nr 0 type 1 extent data offset 0 nr 8192 ram 94208 item 28 key (280 108 208896) itemoff 14545 itemsize 53 extent data disk bytenr 10433142784 nr 86016 type 1 extent data offset 0 nr 86016 ram 86016 item 29 key (280 108 294912) itemoff 14492 itemsize 53 extent data disk bytenr 10433052672 nr 81920 type 1 extent data offset 0 nr 8192 ram 81920 item 30 key (280 108 303104) itemoff 14439 itemsize 53 extent data disk bytenr 10433052672 nr 81920 type 2 extent data offset 8192 nr 73728 ram 81920 9) After btrfs_next_leaf() returns, we have our path pointing to that same leaf and at slot 30, since it has a key we didn't have before and it's the first key greater then the key that was previously the last key of the leaf (key (280 108 294912)); 10) The extent item at slot 30 covers the range from 303104 to 376831 which is in our target range, so we process it, despite having already created an ordered extent against this extent for the file range from 348160 to 376831. This is because we skip to the next extent item only if its end is less than or equals to the start of our delalloc range, and not less than or equals to the current offset ('cur_offset'); 11) As a result we compute 'num_bytes' as: num_bytes = min(end + 1, extent_end) - cur_offset; = min(438271 + 1, 376832) - 376832 = 0 12) We then call create_io_em() for a 0 bytes range starting at offset 376832; 13) Then create_io_em() enters an infinite loop because its calls to btrfs_drop_extent_cache() do nothing due to the 0 length range passed to it. So no existing extent maps that cover the offset 376832 get removed, and therefore calls to add_extent_mapping() return -EEXIST, resulting in an infinite loop. This loop from create_io_em() is the following: do { btrfs_drop_extent_cache(BTRFS_I(inode), em->start, em->start + em->len - 1, 0); write_lock(&em_tree->lock); ret = add_extent_mapping(em_tree, em, 1); write_unlock(&em_tree->lock); /* * The caller has taken lock_extent(), who could race with us * to add em? */ } while (ret == -EEXIST); Also, each call to btrfs_drop_extent_cache() triggers a warning because the start offset passed to it (376832) is smaller then the end offset (376832 - 1) passed to it by -1, due to the 0 length: [258532.052621] ------------[ cut here ]------------ [258532.052643] WARNING: CPU: 0 PID: 9987 at fs/btrfs/file.c:602 btrfs_drop_extent_cache+0x3f4/0x590 [btrfs] (...) [258532.052672] CPU: 0 PID: 9987 Comm: fsx Tainted: G W 5.4.0-rc7-btrfs-next-64 #1 [258532.052673] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.12.0-0-ga698c8995f-prebuilt.qemu.org 04/01/2014 [258532.052691] RIP: 0010:btrfs_drop_extent_cache+0x3f4/0x590 [btrfs] (...) [258532.052695] RSP: 0018:ffffb4be0153f860 EFLAGS: 00010287 [258532.052700] RAX: ffff975b445ee360 RBX: ffff975b44eb3e08 RCX: 0000000000000000 [258532.052700] RDX: 0000000000038fff RSI: 0000000000039000 RDI: ffff975b445ee308 [258532.052700] RBP: 0000000000038fff R08: 0000000000000000 R09: 0000000000000001 [258532.052701] R10: ffff975b513c5c10 R11: 00000000e3c0cfa9 R12: 0000000000039000 [258532.052703] R13: ffff975b445ee360 R14: 00000000ffffffef R15: ffff975b445ee308 [258532.052705] FS: 00007f86a821de80(0000) GS:ffff975b76a00000(0000) knlGS:0000000000000000 [258532.052707] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [258532.052708] CR2: 00007fdacf0f3ab4 CR3: 00000001f9d26002 CR4: 00000000003606f0 [258532.052712] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 [258532.052717] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 [258532.052717] Call Trace: [258532.052718] ? preempt_schedule_common+0x32/0x70 [258532.052722] ? ___preempt_schedule+0x16/0x20 [258532.052741] create_io_em+0xff/0x180 [btrfs] [258532.052767] run_delalloc_nocow+0x942/0xb10 [btrfs] [258532.052791] btrfs_run_delalloc_range+0x30b/0x520 [btrfs] [258532.052812] ? find_lock_delalloc_range+0x221/0x250 [btrfs] [258532.052834] writepage_delalloc+0xe4/0x140 [btrfs] [258532.052855] __extent_writepage+0x110/0x4e0 [btrfs] [258532.052876] extent_write_cache_pages+0x21c/0x480 [btrfs] [258532.052906] extent_writepages+0x52/0xb0 [btrfs] [258532.052911] do_writepages+0x23/0x80 [258532.052915] __filemap_fdatawrite_range+0xd2/0x110 [258532.052938] btrfs_fdatawrite_range+0x1b/0x50 [btrfs] [258532.052954] start_ordered_ops+0x57/0xa0 [btrfs] [258532.052973] ? btrfs_sync_file+0x225/0x490 [btrfs] [258532.052988] btrfs_sync_file+0x225/0x490 [btrfs] [258532.052997] __x64_sys_msync+0x199/0x200 [258532.053004] do_syscall_64+0x5c/0x250 [258532.053007] entry_SYSCALL_64_after_hwframe+0x49/0xbe [258532.053010] RIP: 0033:0x7f86a7dfd760 (...) [258532.053014] RSP: 002b:00007ffd99af0368 EFLAGS: 00000246 ORIG_RAX: 000000000000001a [258532.053016] RAX: ffffffffffffffda RBX: 0000000000000ec9 RCX: 00007f86a7dfd760 [258532.053017] RDX: 0000000000000004 RSI: 000000000000836c RDI: 00007f86a8221000 [258532.053019] RBP: 0000000000021ec9 R08: 0000000000000003 R09: 00007f86a812037c [258532.053020] R10: 0000000000000001 R11: 0000000000000246 R12: 00000000000074a3 [258532.053021] R13: 00007f86a8221000 R14: 000000000000836c R15: 0000000000000001 [258532.053032] irq event stamp: 1653450494 [258532.053035] hardirqs last enabled at (1653450493): [<ffffffff9dec69f9>] _raw_spin_unlock_irq+0x29/0x50 [258532.053037] hardirqs last disabled at (1653450494): [<ffffffff9d4048ea>] trace_hardirqs_off_thunk+0x1a/0x20 [258532.053039] softirqs last enabled at (1653449852): [<ffffffff9e200466>] __do_softirq+0x466/0x6bd [258532.053042] softirqs last disabled at (1653449845): [<ffffffff9d4c8a0c>] irq_exit+0xec/0x120 [258532.053043] ---[ end trace 8476fce13d9ce20a ]--- Which results in flooding dmesg/syslog since btrfs_drop_extent_cache() uses WARN_ON() and not WARN_ON_ONCE(). So fix this issue by changing run_delalloc_nocow()'s loop to move to the next extent item when the current extent item ends at at offset less than or equals to the current offset instead of the start offset. Fixes: 80ff385665b7fc ("Btrfs: update nodatacow code v2") CC: stable@vger.kernel.org # 4.4+ Reviewed-by: Josef Bacik <josef@toxicpanda.com> Signed-off-by: Filipe Manana <fdmanana@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
| * btrfs: fix compressed write bio blkcg attributionDennis Zhou2019-12-301-4/+5
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Bio attribution is handled at bio_set_dev() as once we have a device, we have a corresponding request_queue and then can derive the current css. In special cases, we want to attribute to bio to someone else. This can be done by calling bio_associate_blkg_from_css() or kthread_associate_blkcg() depending on the scenario. Btrfs does this for compressed writeback as they are handled by kworkers, so the latter can be done here. Commit 1a41802701ec ("btrfs: drop bio_set_dev where not needed") removes early bio_set_dev() calls prior to submit_stripe_bio(). This breaks the above assumption that we'll have a request_queue when we are doing association. To fix this, switch to using kthread_associate_blkcg(). Without this, we crash in btrfs/024: [ 3052.093088] BUG: kernel NULL pointer dereference, address: 0000000000000510 [ 3052.107013] #PF: supervisor read access in kernel mode [ 3052.107014] #PF: error_code(0x0000) - not-present page [ 3052.107015] PGD 0 P4D 0 [ 3052.107021] Oops: 0000 [#1] SMP [ 3052.138904] CPU: 42 PID: 201270 Comm: kworker/u161:0 Kdump: loaded Not tainted 5.5.0-rc1-00062-g4852d8ac90a9 #712 [ 3052.138905] Hardware name: Quanta Tioga Pass Single Side 01-0032211004/Tioga Pass Single Side, BIOS F08_3A18 12/20/2018 [ 3052.138912] Workqueue: btrfs-delalloc btrfs_work_helper [ 3052.191375] RIP: 0010:bio_associate_blkg_from_css+0x1e/0x3c0 [ 3052.191379] RSP: 0018:ffffc900210cfc90 EFLAGS: 00010282 [ 3052.191380] RAX: 0000000000000000 RBX: ffff88bfe5573c00 RCX: 0000000000000000 [ 3052.191382] RDX: ffff889db48ec2f0 RSI: ffff88bfe5573c00 RDI: ffff889db48ec2f0 [ 3052.191386] RBP: 0000000000000800 R08: 0000000000203bb0 R09: ffff889db16b2400 [ 3052.293364] R10: 0000000000000000 R11: ffff88a07fffde80 R12: ffff889db48ec2f0 [ 3052.293365] R13: 0000000000001000 R14: ffff889de82bc000 R15: ffff889e2b7bdcc8 [ 3052.293367] FS: 0000000000000000(0000) GS:ffff889ffba00000(0000) knlGS:0000000000000000 [ 3052.293368] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 3052.293369] CR2: 0000000000000510 CR3: 0000000002611001 CR4: 00000000007606e0 [ 3052.293370] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 [ 3052.293371] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 [ 3052.293372] PKRU: 55555554 [ 3052.293376] Call Trace: [ 3052.402552] btrfs_submit_compressed_write+0x137/0x390 [ 3052.402558] submit_compressed_extents+0x40f/0x4c0 [ 3052.422401] btrfs_work_helper+0x246/0x5a0 [ 3052.422408] process_one_work+0x200/0x570 [ 3052.438601] ? process_one_work+0x180/0x570 [ 3052.438605] worker_thread+0x4c/0x3e0 [ 3052.438614] kthread+0x103/0x140 [ 3052.460735] ? process_one_work+0x570/0x570 [ 3052.460737] ? kthread_mod_delayed_work+0xc0/0xc0 [ 3052.460744] ret_from_fork+0x24/0x30 Fixes: 1a41802701ec ("btrfs: drop bio_set_dev where not needed") Reported-by: Chris Murphy <chris@colorremedies.com> Signed-off-by: Dennis Zhou <dennis@kernel.org> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
| * btrfs: punt all bios created in btrfs_submit_compressed_write()Dennis Zhou2019-12-301-0/+4
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Compressed writes happen in the background via kworkers. However, this causes bios to be attributed to root bypassing any cgroup limits from the actual writer. We tag the first bio with REQ_CGROUP_PUNT, which will punt the bio to an appropriate cgroup specific workqueue and attribute the IO properly. However, if btrfs_submit_compressed_write() creates a new bio, we don't tag it the same way. Add the appropriate tagging for subsequent bios. Fixes: ec39f7696ccfa ("Btrfs: use REQ_CGROUP_PUNT for worker thread submitted bios") Reviewed-by: Chris Mason <clm@fb.com> Signed-off-by: Dennis Zhou <dennis@kernel.org> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
* | Merge tag 'for-5.5-rc2-tag' of ↵Linus Torvalds2019-12-1717-56/+127
|\| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux Pull btrfs fixes from David Sterba: "A mix of regression fixes and regular fixes for stable trees: - fix swapped error messages for qgroup enable/rescan - fixes for NO_HOLES feature with clone range - fix deadlock between iget/srcu lock/synchronize srcu while freeing an inode - fix double lock on subvolume cross-rename - tree log fixes * fix missing data checksums after replaying a log tree * also teach tree-checker about this problem * skip log replay on orphaned roots - fix maximum devices constraints for RAID1C -3 and -4 - send: don't print warning on read-only mount regarding orphan cleanup - error handling fixes" * tag 'for-5.5-rc2-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux: btrfs: send: remove WARN_ON for readonly mount btrfs: do not leak reloc root if we fail to read the fs root btrfs: skip log replay on orphaned roots btrfs: handle ENOENT in btrfs_uuid_tree_iterate btrfs: abort transaction after failed inode updates in create_subvol Btrfs: fix hole extent items with a zero size after range cloning Btrfs: fix removal logic of the tree mod log that leads to use-after-free issues Btrfs: make tree checker detect checksum items with overlapping ranges Btrfs: fix missing data checksums after replaying a log tree btrfs: return error pointer from alloc_test_extent_buffer btrfs: fix devs_max constraints for raid1c3 and raid1c4 btrfs: tree-checker: Fix error format string for size_t btrfs: don't double lock the subvol_sem for rename exchange btrfs: handle error in btrfs_cache_block_group btrfs: do not call synchronize_srcu() in inode_tree_del Btrfs: fix cloning range with a hole when using the NO_HOLES feature btrfs: Fix error messages in qgroup_rescan_init
| * btrfs: send: remove WARN_ON for readonly mountAnand Jain2019-12-131-6/+0
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | We log warning if root::orphan_cleanup_state is not set to ORPHAN_CLEANUP_DONE in btrfs_ioctl_send(). However if the filesystem is mounted as readonly we skip the orphan item cleanup during the lookup and root::orphan_cleanup_state remains at the init state 0 instead of ORPHAN_CLEANUP_DONE (2). So during send in btrfs_ioctl_send() we hit the warning as below. WARN_ON(send_root->orphan_cleanup_state != ORPHAN_CLEANUP_DONE); WARNING: CPU: 0 PID: 2616 at /Volumes/ws/btrfs-devel/fs/btrfs/send.c:7090 btrfs_ioctl_send+0xb2f/0x18c0 [btrfs] :: RIP: 0010:btrfs_ioctl_send+0xb2f/0x18c0 [btrfs] :: Call Trace: :: _btrfs_ioctl_send+0x7b/0x110 [btrfs] btrfs_ioctl+0x150a/0x2b00 [btrfs] :: do_vfs_ioctl+0xa9/0x620 ? __fget+0xac/0xe0 ksys_ioctl+0x60/0x90 __x64_sys_ioctl+0x16/0x20 do_syscall_64+0x49/0x130 entry_SYSCALL_64_after_hwframe+0x44/0xa9 Reproducer: mkfs.btrfs -fq /dev/sdb mount /dev/sdb /btrfs btrfs subvolume create /btrfs/sv1 btrfs subvolume snapshot -r /btrfs/sv1 /btrfs/ss1 umount /btrfs mount -o ro /dev/sdb /btrfs btrfs send /btrfs/ss1 -f /tmp/f The warning exists because having orphan inodes could confuse send and cause it to fail or produce incorrect streams. The two cases that would cause such send failures, which are already fixed are: 1) Inodes that were unlinked - these are orphanized and remain with a link count of 0. These caused send operations to fail because it expected to always find at least one path for an inode. However this is no longer a problem since send is now able to deal with such inodes since commit 46b2f4590aab ("Btrfs: fix send failure when root has deleted files still open") and treats them as having been completely removed (the state after an orphan cleanup is performed). 2) Inodes that were in the process of being truncated. These resulted in send not knowing about the truncation and potentially issue write operations full of zeroes for the range from the new file size to the old file size. This is no longer a problem because we no longer create orphan items for truncation since commit f7e9e8fc792f ("Btrfs: stop creating orphan items for truncate"). As such before these commits, the WARN_ON here provided a clue in case something went wrong. Instead of being a warning against the root::orphan_cleanup_state value, it could have been more accurate by checking if there were actually any orphan items, and then issue a warning only if any exists, but that would be more expensive to check. Since orphanized inodes no longer cause problems for send, just remove the warning. Reported-by: Christoph Anton Mitterer <calestyo@scientia.net> Link: https://lore.kernel.org/linux-btrfs/21cb5e8d059f6e1496a903fa7bfc0a297e2f5370.camel@scientia.net/ CC: stable@vger.kernel.org # 4.19+ Suggested-by: Filipe Manana <fdmanana@suse.com> Reviewed-by: Filipe Manana <fdmanana@suse.com> Signed-off-by: Anand Jain <anand.jain@oracle.com> Signed-off-by: David Sterba <dsterba@suse.com>
| * btrfs: do not leak reloc root if we fail to read the fs rootJosef Bacik2019-12-131-0/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | If we fail to read the fs root corresponding with a reloc root we'll just break out and free the reloc roots. But we remove our current reloc_root from this list higher up, which means we'll leak this reloc_root. Fix this by adding ourselves back to the reloc_roots list so we are properly cleaned up. CC: stable@vger.kernel.org # 4.4+ Reviewed-by: Filipe Manana <fdmanana@suse.com> Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de> Signed-off-by: Josef Bacik <josef@toxicpanda.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
| * btrfs: skip log replay on orphaned rootsJosef Bacik2019-12-131-2/+21
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | My fsstress modifications coupled with generic/475 uncovered a failure to mount and replay the log if we hit a orphaned root. We do not want to replay the log for an orphan root, but it's completely legitimate to have an orphaned root with a log attached. Fix this by simply skipping replaying the log. We still need to pin it's root node so that we do not overwrite it while replaying other logs, as we re-read the log root at every stage of the replay. CC: stable@vger.kernel.org # 4.4+ Reviewed-by: Filipe Manana <fdmanana@suse.com> Signed-off-by: Josef Bacik <josef@toxicpanda.com> Signed-off-by: David Sterba <dsterba@suse.com>
| * btrfs: handle ENOENT in btrfs_uuid_tree_iterateJosef Bacik2019-12-131-0/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | If we get an -ENOENT back from btrfs_uuid_iter_rem when iterating the uuid tree we'll just continue and do btrfs_next_item(). However we've done a btrfs_release_path() at this point and no longer have a valid path. So increment the key and go back and do a normal search. CC: stable@vger.kernel.org # 4.4+ Reviewed-by: Filipe Manana <fdmanana@suse.com> Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de> Signed-off-by: Josef Bacik <josef@toxicpanda.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
| * btrfs: abort transaction after failed inode updates in create_subvolJosef Bacik2019-12-131-2/+8
| | | | | | | | | | | | | | | | | | | | | | | | We can just abort the transaction here, and in fact do that for every other failure in this function except these two cases. CC: stable@vger.kernel.org # 4.4+ Reviewed-by: Filipe Manana <fdmanana@suse.com> Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de> Signed-off-by: Josef Bacik <josef@toxicpanda.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
| * Btrfs: fix hole extent items with a zero size after range cloningFilipe Manana2019-12-131-11/+5
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Normally when cloning a file range if we find an implicit hole at the end of the range we assume it is because the NO_HOLES feature is enabled. However that is not always the case. One well known case [1] is when we have a power failure after mixing buffered and direct IO writes against the same file. In such cases we need to punch a hole in the destination file, and if the NO_HOLES feature is not enabled, we need to insert explicit file extent items to represent the hole. After commit 690a5dbfc51315 ("Btrfs: fix ENOSPC errors, leading to transaction aborts, when cloning extents"), we started to insert file extent items representing the hole with an item size of 0, which is invalid and should be 53 bytes (the size of a btrfs_file_extent_item structure), resulting in all sorts of corruptions and invalid memory accesses. This is detected by the tree checker when we attempt to write a leaf to disk. The problem can be sporadically triggered by test case generic/561 from fstests. That test case does not exercise power failure and creates a new filesystem when it starts, so it does not use a filesystem created by any previous test that tests power failure. However the test does both buffered and direct IO writes (through fsstress) and it's precisely that which is creating the implicit holes in files. That happens even before the commit mentioned earlier. I need to investigate why we get those implicit holes to check if there is a real problem or not. For now this change fixes the regression of introducing file extent items with an item size of 0 bytes. Fix the issue by calling btrfs_punch_hole_range() without passing a btrfs_clone_extent_info structure, which ensures file extent items are inserted to represent the hole with a correct item size. We were passing a btrfs_clone_extent_info with a value of 0 for its 'item_size' field, which was causing the insertion of file extent items with an item size of 0. [1] https://www.spinics.net/lists/linux-btrfs/msg75350.html Reported-by: David Sterba <dsterba@suse.com> Fixes: 690a5dbfc51315 ("Btrfs: fix ENOSPC errors, leading to transaction aborts, when cloning extents") Signed-off-by: Filipe Manana <fdmanana@suse.com> Reviewed-by: Josef Bacik <josef@toxicpanda.com> Signed-off-by: David Sterba <dsterba@suse.com>
| * Btrfs: fix removal logic of the tree mod log that leads to use-after-free issuesFilipe Manana2019-12-131-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | When a tree mod log user no longer needs to use the tree it calls btrfs_put_tree_mod_seq() to remove itself from the list of users and delete all no longer used elements of the tree's red black tree, which should be all elements with a sequence number less then our equals to the caller's sequence number. However the logic is broken because it can delete and free elements from the red black tree that have a sequence number greater then the caller's sequence number: 1) At a point in time we have sequence numbers 1, 2, 3 and 4 in the tree mod log; 2) The task which got assigned the sequence number 1 calls btrfs_put_tree_mod_seq(); 3) Sequence number 1 is deleted from the list of sequence numbers; 4) The current minimum sequence number is computed to be the sequence number 2; 5) A task using sequence number 2 is at tree_mod_log_rewind() and gets a pointer to one of its elements from the red black tree through a call to tree_mod_log_search(); 6) The task with sequence number 1 iterates the red black tree of tree modification elements and deletes (and frees) all elements with a sequence number less then or equals to 2 (the computed minimum sequence number) - it ends up only leaving elements with sequence numbers of 3 and 4; 7) The task with sequence number 2 now uses the pointer to its element, already freed by the other task, at __tree_mod_log_rewind(), resulting in a use-after-free issue. When CONFIG_DEBUG_PAGEALLOC=y it produces a trace like the following: [16804.546854] general protection fault: 0000 [#1] PREEMPT SMP DEBUG_PAGEALLOC PTI [16804.547451] CPU: 0 PID: 28257 Comm: pool Tainted: G W 5.4.0-rc8-btrfs-next-51 #1 [16804.548059] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.12.0-0-ga698c8995f-prebuilt.qemu.org 04/01/2014 [16804.548666] RIP: 0010:rb_next+0x16/0x50 (...) [16804.550581] RSP: 0018:ffffb948418ef9b0 EFLAGS: 00010202 [16804.551227] RAX: 6b6b6b6b6b6b6b6b RBX: ffff90e0247f6600 RCX: 6b6b6b6b6b6b6b6b [16804.551873] RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffff90e0247f6600 [16804.552504] RBP: ffff90dffe0d4688 R08: 0000000000000001 R09: 0000000000000000 [16804.553136] R10: ffff90dffa4a0040 R11: 0000000000000000 R12: 000000000000002e [16804.553768] R13: ffff90e0247f6600 R14: 0000000000001663 R15: ffff90dff77862b8 [16804.554399] FS: 00007f4b197ae700(0000) GS:ffff90e036a00000(0000) knlGS:0000000000000000 [16804.555039] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [16804.555683] CR2: 00007f4b10022000 CR3: 00000002060e2004 CR4: 00000000003606f0 [16804.556336] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 [16804.556968] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 [16804.557583] Call Trace: [16804.558207] __tree_mod_log_rewind+0xbf/0x280 [btrfs] [16804.558835] btrfs_search_old_slot+0x105/0xd00 [btrfs] [16804.559468] resolve_indirect_refs+0x1eb/0xc70 [btrfs] [16804.560087] ? free_extent_buffer.part.19+0x5a/0xc0 [btrfs] [16804.560700] find_parent_nodes+0x388/0x1120 [btrfs] [16804.561310] btrfs_check_shared+0x115/0x1c0 [btrfs] [16804.561916] ? extent_fiemap+0x59d/0x6d0 [btrfs] [16804.562518] extent_fiemap+0x59d/0x6d0 [btrfs] [16804.563112] ? __might_fault+0x11/0x90 [16804.563706] do_vfs_ioctl+0x45a/0x700 [16804.564299] ksys_ioctl+0x70/0x80 [16804.564885] ? trace_hardirqs_off_thunk+0x1a/0x20 [16804.565461] __x64_sys_ioctl+0x16/0x20 [16804.566020] do_syscall_64+0x5c/0x250 [16804.566580] entry_SYSCALL_64_after_hwframe+0x49/0xbe [16804.567153] RIP: 0033:0x7f4b1ba2add7 (...) [16804.568907] RSP: 002b:00007f4b197adc88 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 [16804.569513] RAX: ffffffffffffffda RBX: 00007f4b100210d8 RCX: 00007f4b1ba2add7 [16804.570133] RDX: 00007f4b100210d8 RSI: 00000000c020660b RDI: 0000000000000003 [16804.570726] RBP: 000055de05a6cfe0 R08: 0000000000000000 R09: 00007f4b197add44 [16804.571314] R10: 0000000000000000 R11: 0000000000000246 R12: 00007f4b197add48 [16804.571905] R13: 00007f4b197add40 R14: 00007f4b100210d0 R15: 00007f4b197add50 (...) [16804.575623] ---[ end trace 87317359aad4ba50 ]--- Fix this by making btrfs_put_tree_mod_seq() skip deletion of elements that have a sequence number equals to the computed minimum sequence number, and not just elements with a sequence number greater then that minimum. Fixes: bd989ba359f2ac ("Btrfs: add tree modification log functions") CC: stable@vger.kernel.org # 4.4+ Reviewed-by: Josef Bacik <josef@toxicpanda.com> Signed-off-by: Filipe Manana <fdmanana@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
| * Btrfs: make tree checker detect checksum items with overlapping rangesFilipe Manana2019-12-131-2/+16
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Having checksum items, either on the checksums tree or in a log tree, that represent ranges that overlap each other is a sign of a corruption. Such case confuses the checksum lookup code and can result in not being able to find checksums or find stale checksums. So add a check for such case. This is motivated by a recent fix for a case where a log tree had checksum items covering ranges that overlap each other due to extent cloning, and resulted in missing checksums after replaying the log tree. It also helps detect past issues such as stale and outdated checksums due to overlapping, commit 27b9a8122ff71a ("Btrfs: fix csum tree corruption, duplicate and outdated checksums"). CC: stable@vger.kernel.org # 4.4+ Signed-off-by: Filipe Manana <fdmanana@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
| * Btrfs: fix missing data checksums after replaying a log treeFilipe Manana2019-12-134-9/+36
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | When logging a file that has shared extents (reflinked with other files or with itself), we can end up logging multiple checksum items that cover overlapping ranges. This confuses the search for checksums at log replay time causing some checksums to never be added to the fs/subvolume tree. Consider the following example of a file that shares the same extent at offsets 0 and 256Kb: [ bytenr 13893632, offset 64Kb, len 64Kb ] 0 64Kb [ bytenr 13631488, offset 64Kb, len 192Kb ] 64Kb 256Kb [ bytenr 13893632, offset 0, len 256Kb ] 256Kb 512Kb When logging the inode, at tree-log.c:copy_items(), when processing the file extent item at offset 0, we log a checksum item covering the range 13959168 to 14024704, which corresponds to 13893632 + 64Kb and 13893632 + 64Kb + 64Kb, respectively. Later when processing the extent item at offset 256K, we log the checksums for the range from 13893632 to 14155776 (which corresponds to 13893632 + 256Kb). These checksums get merged with the checksum item for the range from 13631488 to 13893632 (13631488 + 256Kb), logged by a previous fsync. So after this we get the two following checksum items in the log tree: (...) item 6 key (EXTENT_CSUM EXTENT_CSUM 13631488) itemoff 3095 itemsize 512 range start 13631488 end 14155776 length 524288 item 7 key (EXTENT_CSUM EXTENT_CSUM 13959168) itemoff 3031 itemsize 64 range start 13959168 end 14024704 length 65536 The first one covers the range from the second one, they overlap. So far this does not cause a problem after replaying the log, because when replaying the file extent item for offset 256K, we copy all the checksums for the extent 13893632 from the log tree to the fs/subvolume tree, since searching for an checksum item for bytenr 13893632 leaves us at the first checksum item, which covers the whole range of the extent. However if we write 64Kb to file offset 256Kb for example, we will not be able to find and copy the checksums for the last 128Kb of the extent at bytenr 13893632, referenced by the file range 384Kb to 512Kb. After writing 64Kb into file offset 256Kb we get the following extent layout for our file: [ bytenr 13893632, offset 64K, len 64Kb ] 0 64Kb [ bytenr 13631488, offset 64Kb, len 192Kb ] 64Kb 256Kb [ bytenr 14155776, offset 0, len 64Kb ] 256Kb 320Kb [ bytenr 13893632, offset 64Kb, len 192Kb ] 320Kb 512Kb After fsync'ing the file, if we have a power failure and then mount the filesystem to replay the log, the following happens: 1) When replaying the file extent item for file offset 320Kb, we lookup for the checksums for the extent range from 13959168 (13893632 + 64Kb) to 14155776 (13893632 + 256Kb), through a call to btrfs_lookup_csums_range(); 2) btrfs_lookup_csums_range() finds the checksum item that starts precisely at offset 13959168 (item 7 in the log tree, shown before); 3) However that checksum item only covers 64Kb of data, and not 192Kb of data; 4) As a result only the checksums for the first 64Kb of data referenced by the file extent item are found and copied to the fs/subvolume tree. The remaining 128Kb of data, file range 384Kb to 512Kb, doesn't get the corresponding data checksums found and copied to the fs/subvolume tree. 5) After replaying the log userspace will not be able to read the file range from 384Kb to 512Kb, because the checksums are missing and resulting in an -EIO error. The following steps reproduce this scenario: $ mkfs.btrfs -f /dev/sdc $ mount /dev/sdc /mnt/sdc $ xfs_io -f -c "pwrite -S 0xa3 0 256K" /mnt/sdc/foobar $ xfs_io -c "fsync" /mnt/sdc/foobar $ xfs_io -c "pwrite -S 0xc7 256K 256K" /mnt/sdc/foobar $ xfs_io -c "reflink /mnt/sdc/foobar 320K 0 64K" /mnt/sdc/foobar $ xfs_io -c "fsync" /mnt/sdc/foobar $ xfs_io -c "pwrite -S 0xe5 256K 64K" /mnt/sdc/foobar $ xfs_io -c "fsync" /mnt/sdc/foobar <power failure> $ mount /dev/sdc /mnt/sdc $ md5sum /mnt/sdc/foobar md5sum: /mnt/sdc/foobar: Input/output error $ dmesg | tail [165305.003464] BTRFS info (device sdc): no csum found for inode 257 start 401408 [165305.004014] BTRFS info (device sdc): no csum found for inode 257 start 405504 [165305.004559] BTRFS info (device sdc): no csum found for inode 257 start 409600 [165305.005101] BTRFS info (device sdc): no csum found for inode 257 start 413696 [165305.005627] BTRFS info (device sdc): no csum found for inode 257 start 417792 [165305.006134] BTRFS info (device sdc): no csum found for inode 257 start 421888 [165305.006625] BTRFS info (device sdc): no csum found for inode 257 start 425984 [165305.007278] BTRFS info (device sdc): no csum found for inode 257 start 430080 [165305.008248] BTRFS warning (device sdc): csum failed root 5 ino 257 off 393216 csum 0x1337385e expected csum 0x00000000 mirror 1 [165305.009550] BTRFS warning (device sdc): csum failed root 5 ino 257 off 393216 csum 0x1337385e expected csum 0x00000000 mirror 1 Fix this simply by deleting first any checksums, from the log tree, for the range of the extent we are logging at copy_items(). This ensures we do not get checksum items in the log tree that have overlapping ranges. This is a long time issue that has been present since we have the clone (and deduplication) ioctl, and can happen both when an extent is shared between different files and within the same file. A test case for fstests follows soon. CC: stable@vger.kernel.org # 4.4+ Signed-off-by: Filipe Manana <fdmanana@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
| * btrfs: return error pointer from alloc_test_extent_bufferDan Carpenter2019-12-133-6/+8
| | | | | | | | | | | | | | | | | | | | | | | | | | | | Callers of alloc_test_extent_buffer have not correctly interpreted the return value as error pointer, as alloc_test_extent_buffer should behave as alloc_extent_buffer. The self-tests were unaffected but btrfs_find_create_tree_block could call both functions and that would cause problems up in the call chain. Fixes: faa2dbf004e8 ("Btrfs: add sanity tests for new qgroup accounting code") CC: stable@vger.kernel.org # 4.4+ Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
| * btrfs: fix devs_max constraints for raid1c3 and raid1c4David Sterba2019-12-131-2/+2
| | | | | | | | | | | | | | | | | | | | | | The value 0 for devs_max means to spread the allocated chunks over all available devices, eg. stripe for RAID0 or RAID5. This got mistakenly copied to the RAID1C3/4 profiles. The intention is to have exactly 3 and 4 copies respectively. Fixes: 47e6f7423b91 ("btrfs: add support for 3-copy replication (raid1c3)") Fixes: 8d6fac0087e5 ("btrfs: add support for 4-copy replication (raid1c4)") Signed-off-by: David Sterba <dsterba@suse.com>
| * btrfs: tree-checker: Fix error format string for size_tAndreas Färber2019-12-131-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Argument BTRFS_FILE_EXTENT_INLINE_DATA_START is defined as offsetof(), which returns type size_t, so we need %zu instead of %lu. This fixes a build warning on 32-bit ARM: ../fs/btrfs/tree-checker.c: In function 'check_extent_data_item': ../fs/btrfs/tree-checker.c:230:43: warning: format '%lu' expects argument of type 'long unsigned int', but argument 5 has type 'unsigned int' [-Wformat=] 230 | "invalid item size, have %u expect [%lu, %u)", | ~~^ | long unsigned int | %u Fixes: 153a6d299956 ("btrfs: tree-checker: Check item size before reading file extent type") Acked-by: Geert Uytterhoeven <geert@linux-m68k.org> Signed-off-by: Andreas Färber <afaerber@suse.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
| * btrfs: don't double lock the subvol_sem for rename exchangeJosef Bacik2019-12-131-6/+4
| | | | | | | | | | | | | | | | | | | | | | If we're rename exchanging two subvols we'll try to lock this lock twice, which is bad. Just lock once if either of the ino's are subvols. Fixes: cdd1fedf8261 ("btrfs: add support for RENAME_EXCHANGE and RENAME_WHITEOUT") CC: stable@vger.kernel.org # 4.4+ Signed-off-by: Josef Bacik <josef@toxicpanda.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
| * btrfs: handle error in btrfs_cache_block_groupJosef Bacik2019-12-131-2/+18
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | We have a BUG_ON(ret < 0) in find_free_extent from btrfs_cache_block_group. If we fail to allocate our ctl we'll just panic, which is not good. Instead just go on to another block group. If we fail to find a block group we don't want to return ENOSPC, because really we got a ENOMEM and that's the root of the problem. Save our return from btrfs_cache_block_group(), and then if we still fail to make our allocation return that ret so we get the right error back. Tested with inject-error.py from bcc. Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de> Signed-off-by: Josef Bacik <josef@toxicpanda.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
| * btrfs: do not call synchronize_srcu() in inode_tree_delJosef Bacik2019-12-131-2/+0
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Testing with the new fsstress uncovered a pretty nasty deadlock with lookup and snapshot deletion. Process A unlink -> final iput -> inode_tree_del -> synchronize_srcu(subvol_srcu) Process B btrfs_lookup <- srcu_read_lock() acquired here -> btrfs_iget -> find inode that has I_FREEING set -> __wait_on_freeing_inode() We're holding the srcu_read_lock() while doing the iget in order to make sure our fs root doesn't go away, and then we are waiting for the inode to finish freeing. However because the free'ing process is doing a synchronize_srcu() we deadlock. Fix this by dropping the synchronize_srcu() in inode_tree_del(). We don't need people to stop accessing the fs root at this point, we're only adding our empty root to the dead roots list. A larger much more invasive fix is forthcoming to address how we deal with fs roots, but this fixes the immediate problem. Fixes: 76dda93c6ae2 ("Btrfs: add snapshot/subvolume destroy ioctl") CC: stable@vger.kernel.org # 4.4+ Signed-off-by: Josef Bacik <josef@toxicpanda.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
| * Btrfs: fix cloning range with a hole when using the NO_HOLES featureFilipe Manana2019-12-131-2/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | When using the NO_HOLES feature if we clone a range that contains a hole and a temporary ENOSPC happens while dropping extents from the target inode's range, we can end up failing and aborting the transaction with -EEXIST or with a corrupt file extent item, that has a length greater than it should and overlaps with other extents. For example when cloning the following range from inode A to inode B: Inode A: extent A1 extent A2 [ ----------- ] [ hole, implicit, 4MB length ] [ ------------- ] 0 1MB 5MB 6MB Range to clone: [1MB, 6MB) Inode B: extent B1 extent B2 extent B3 extent B4 [ ---------- ] [ --------- ] [ ---------- ] [ ---------- ] 0 1MB 1MB 2MB 2MB 5MB 5MB 6MB Target range: [1MB, 6MB) (same as source, to make it easier to explain) The following can happen: 1) btrfs_punch_hole_range() gets -ENOSPC from __btrfs_drop_extents(); 2) At that point, 'cur_offset' is set to 1MB and __btrfs_drop_extents() set 'drop_end' to 2MB, meaning it was able to drop only extent B2; 3) We then compute 'clone_len' as 'drop_end' - 'cur_offset' = 2MB - 1MB = 1MB; 4) We then attempt to insert a file extent item at inode B with a file offset of 5MB, which is the value of clone_info->file_offset. This fails with error -EEXIST because there's already an extent at that offset (extent B4); 5) We abort the current transaction with -EEXIST and return that error to user space as well. Another example, for extent corruption: Inode A: extent A1 extent A2 [ ----------- ] [ hole, implicit, 10MB length ] [ ------------- ] 0 1MB 11MB 12MB Inode B: extent B1 extent B2 [ ----------- ] [ --------- ] [ ----------------------------- ] 0 1MB 1MB 5MB 5MB 12MB Target range: [1MB, 12MB) (same as source, to make it easier to explain) 1) btrfs_punch_hole_range() gets -ENOSPC from __btrfs_drop_extents(); 2) At that point, 'cur_offset' is set to 1MB and __btrfs_drop_extents() set 'drop_end' to 5MB, meaning it was able to drop only extent B2; 3) We then compute 'clone_len' as 'drop_end' - 'cur_offset' = 5MB - 1MB = 4MB; 4) We then insert a file extent item at inode B with a file offset of 11MB which is the value of clone_info->file_offset, and a length of 4MB (the value of 'clone_len'). So we get 2 extents items with ranges that overlap and an extent length of 4MB, larger then the extent A2 from inode A (1MB length); 5) After that we end the transaction, balance the btree dirty pages and then start another or join the previous transaction. It might happen that the transaction which inserted the incorrect extent was committed by another task so we end up with extent corruption if a power failure happens. So fix this by making sure we attempt to insert the extent to clone at the destination inode only if we are past dropping the sub-range that corresponds to a hole. Fixes: 690a5dbfc51315 ("Btrfs: fix ENOSPC errors, leading to transaction aborts, when cloning extents") Signed-off-by: Filipe Manana <fdmanana@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
| * btrfs: Fix error messages in qgroup_rescan_initNikolay Borisov2019-12-131-2/+2
| | | | | | | | | | | | | | | | | | | | | | The branch of qgroup_rescan_init which is executed from the mount path prints wrong errors messages. The textual print out in case BTRFS_QGROUP_STATUS_FLAG_RESCAN/BTRFS_QGROUP_STATUS_FLAG_ON are not set are transposed. Fix it by exchanging their place. Signed-off-by: Nikolay Borisov <nborisov@suse.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
* | btrfs: add Kconfig dependency for BLAKE2BDavid Sterba2019-12-091-0/+1
| | | | | | | | | | | | | | | | Because the BLAKE2B code went through a different tree, it was not available at the time the btrfs part was merged. Now that the Kconfig symbol exists, add it to the list. Signed-off-by: David Sterba <dsterba@suse.com>
* | Merge tag 'compat-ioctl-5.5' of ↵Linus Torvalds2019-12-011-1/+1
|\ \ | |/ |/| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org:/pub/scm/linux/kernel/git/arnd/playground Pull removal of most of fs/compat_ioctl.c from Arnd Bergmann: "As part of the cleanup of some remaining y2038 issues, I came to fs/compat_ioctl.c, which still has a couple of commands that need support for time64_t. In completely unrelated work, I spent time on cleaning up parts of this file in the past, moving things out into drivers instead. After Al Viro reviewed an earlier version of this series and did a lot more of that cleanup, I decided to try to completely eliminate the rest of it and move it all into drivers. This series incorporates some of Al's work and many patches of my own, but in the end stops short of actually removing the last part, which is the scsi ioctl handlers. I have patches for those as well, but they need more testing or possibly a rewrite" * tag 'compat-ioctl-5.5' of git://git.kernel.org:/pub/scm/linux/kernel/git/arnd/playground: (42 commits) scsi: sd: enable compat ioctls for sed-opal pktcdvd: add compat_ioctl handler compat_ioctl: move SG_GET_REQUEST_TABLE handling compat_ioctl: ppp: move simple commands into ppp_generic.c compat_ioctl: handle PPPIOCGIDLE for 64-bit time_t compat_ioctl: move PPPIOCSCOMPRESS to ppp_generic compat_ioctl: unify copy-in of ppp filters tty: handle compat PPP ioctls compat_ioctl: move SIOCOUTQ out of compat_ioctl.c compat_ioctl: handle SIOCOUTQNSD af_unix: add compat_ioctl support compat_ioctl: reimplement SG_IO handling compat_ioctl: move WDIOC handling into wdt drivers fs: compat_ioctl: move FITRIM emulation into file systems gfs2: add compat_ioctl support compat_ioctl: remove unused convert_in_user macro compat_ioctl: remove last RAID handling code compat_ioctl: remove /dev/raw ioctl translation compat_ioctl: remove PCI ioctl translation compat_ioctl: remove joystick ioctl translation ...
| * compat_ioctl: move more drivers to compat_ptr_ioctlArnd Bergmann2019-10-231-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The .ioctl and .compat_ioctl file operations have the same prototype so they can both point to the same function, which works great almost all the time when all the commands are compatible. One exception is the s390 architecture, where a compat pointer is only 31 bit wide, and converting it into a 64-bit pointer requires calling compat_ptr(). Most drivers here will never run in s390, but since we now have a generic helper for it, it's easy enough to use it consistently. I double-checked all these drivers to ensure that all ioctl arguments are used as pointers or are ignored, but are not interpreted as integer values. Acked-by: Jason Gunthorpe <jgg@mellanox.com> Acked-by: Daniel Vetter <daniel.vetter@ffwll.ch> Acked-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org> Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Acked-by: David Sterba <dsterba@suse.com> Acked-by: Darren Hart (VMware) <dvhart@infradead.org> Acked-by: Jonathan Cameron <Jonathan.Cameron@huawei.com> Acked-by: Bjorn Andersson <bjorn.andersson@linaro.org> Acked-by: Dan Williams <dan.j.williams@intel.com> Signed-off-by: Arnd Bergmann <arnd@arndb.de>
* | btrfs: drop bdev argument from submit_extent_pageDavid Sterba2019-11-181-8/+3
| | | | | | | | | | | | | | | | After previous patches removing bdev being passed around to set it to bio, it has become unused in submit_extent_page. So it now has "only" 13 parameters. Signed-off-by: David Sterba <dsterba@suse.com>
* | btrfs: remove extent_map::bdevDavid Sterba2019-11-188-31/+2
| | | | | | | | | | | | | | | | We can now remove the bdev from extent_map. Previous patches made sure that bio_set_dev is correctly in all places and that we don't need to grab it from latest_bdev or pass it around inside the extent map. Signed-off-by: David Sterba <dsterba@suse.com>
* | btrfs: drop bio_set_dev where not neededDavid Sterba2019-11-182-11/+0
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | bio_set_dev sets a bdev to a bio and is not only setting a pointer bug also changing some state bits if there was a different bdev set before. This is one thing that's not needed. Another thing is that setting a bdev at bio allocation time is too early and actually does not work with plain redundancy profiles, where each time we submit a bio to a device, the bdev is set correctly. In many places the bio bdev is set to latest_bdev that seems to serve as a stub pointer "just to put something to bio". But we don't have to do that. Where do we know which bdev to set: * for regular IO: submit_stripe_bio that's called by btrfs_map_bio * repair IO: repair_io_failure, read or write from specific device * super block write (using buffer_heads but uses raw bdev) and barriers * scrub: this does not use all regular IO paths as it needs to reach all copies, verify and fixup eventually, and for that all bdev management is independent * raid56: rbio_add_io_page, for the RMW write * integrity-checker: does it's own low-level block tracking Signed-off-by: David Sterba <dsterba@suse.com>
* | btrfs: get bdev directly from fs_devices in submit_extent_pageDavid Sterba2019-11-181-1/+4
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This is preparatory patch to remove @bdev parameter from submit_extent_page. It can't be removed completely, because the cgroups need it for wbc when initializing the bio wbc_init_bio bio_associate_blkg_from_css dereference bdev->bi_disk->queue The bdev pointer is the same as latest_bdev, thus no functional change. We can retrieve it from fs_devices that's reachable through several dereferences. The local variable shadows the parameter, but that's only temporary. Signed-off-by: David Sterba <dsterba@suse.com>
* | btrfs: record all roots for rename exchange on a subvolJosef Bacik2019-11-181-0/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Testing with the new fsstress support for subvolumes uncovered a pretty bad problem with rename exchange on subvolumes. We're modifying two different subvolumes, but we only start the transaction on one of them, so the other one is not added to the dirty root list. This is caught by btrfs_cow_block() with a warning because the root has not been updated, however if we do not modify this root again we'll end up pointing at an invalid root because the root item is never updated. Fix this by making sure we add the destination root to the trans list, the same as we do with normal renames. This fixes the corruption. Fixes: cdd1fedf8261 ("btrfs: add support for RENAME_EXCHANGE and RENAME_WHITEOUT") CC: stable@vger.kernel.org # 4.9+ Reviewed-by: Filipe Manana <fdmanana@suse.com> Signed-off-by: Josef Bacik <josef@toxicpanda.com> Signed-off-by: David Sterba <dsterba@suse.com>
* | Btrfs: fix block group remaining RO forever after error during device replaceFilipe Manana2019-11-183-45/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | When doing a device replace, while at scrub.c:scrub_enumerate_chunks(), we set the block group to RO mode and then wait for any ongoing writes into extents of the block group to complete. While doing that wait we overwrite the value of the variable 'ret' and can break out of the loop if an error happens without turning the block group back into RW mode. So what happens is the following: 1) btrfs_inc_block_group_ro() returns 0, meaning it set the block group to RO mode (its ->ro field set to 1 or incremented to some value > 1); 2) Then btrfs_wait_ordered_roots() returns a value > 0; 3) Then if either joining or committing the transaction fails, we break out of the loop wihtout calling btrfs_dec_block_group_ro(), leaving the block group in RO mode forever. To fix this, just remove the code that waits for ongoing writes to extents of the block group, since it's not needed because in the initial setup phase of a device replace operation, before starting to find all chunks and their extents, we set the target device for replace while holding fs_info->dev_replace->rwsem, which ensures that after releasing that semaphore, any writes into the source device are made to the target device as well (__btrfs_map_block() guarantees that). So while at scrub_enumerate_chunks() we only need to worry about finding and copying extents (from the source device to the target device) that were written before we started the device replace operation. Fixes: f0e9b7d6401959 ("Btrfs: fix race setting block group readonly during device replace") Signed-off-by: Filipe Manana <fdmanana@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
* | btrfs: scrub: Don't check free space before marking a block group ROQu Wenruo2019-11-184-20/+54
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | [BUG] When running btrfs/072 with only one online CPU, it has a pretty high chance to fail: btrfs/072 12s ... _check_dmesg: something found in dmesg (see xfstests-dev/results//btrfs/072.dmesg) - output mismatch (see xfstests-dev/results//btrfs/072.out.bad) --- tests/btrfs/072.out 2019-10-22 15:18:14.008965340 +0800 +++ /xfstests-dev/results//btrfs/072.out.bad 2019-11-14 15:56:45.877152240 +0800 @@ -1,2 +1,3 @@ QA output created by 072 Silence is golden +Scrub find errors in "-m dup -d single" test ... And with the following call trace: BTRFS info (device dm-5): scrub: started on devid 1 ------------[ cut here ]------------ BTRFS: Transaction aborted (error -27) WARNING: CPU: 0 PID: 55087 at fs/btrfs/block-group.c:1890 btrfs_create_pending_block_groups+0x3e6/0x470 [btrfs] CPU: 0 PID: 55087 Comm: btrfs Tainted: G W O 5.4.0-rc1-custom+ #13 Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 0.0.0 02/06/2015 RIP: 0010:btrfs_create_pending_block_groups+0x3e6/0x470 [btrfs] Call Trace: __btrfs_end_transaction+0xdb/0x310 [btrfs] btrfs_end_transaction+0x10/0x20 [btrfs] btrfs_inc_block_group_ro+0x1c9/0x210 [btrfs] scrub_enumerate_chunks+0x264/0x940 [btrfs] btrfs_scrub_dev+0x45c/0x8f0 [btrfs] btrfs_ioctl+0x31a1/0x3fb0 [btrfs] do_vfs_ioctl+0x636/0xaa0 ksys_ioctl+0x67/0x90 __x64_sys_ioctl+0x43/0x50 do_syscall_64+0x79/0xe0 entry_SYSCALL_64_after_hwframe+0x49/0xbe ---[ end trace 166c865cec7688e7 ]--- [CAUSE] The error number -27 is -EFBIG, returned from the following call chain: btrfs_end_transaction() |- __btrfs_end_transaction() |- btrfs_create_pending_block_groups() |- btrfs_finish_chunk_alloc() |- btrfs_add_system_chunk() This happens because we have used up all space of btrfs_super_block::sys_chunk_array. The root cause is, we have the following bad loop of creating tons of system chunks: 1. The only SYSTEM chunk is being scrubbed It's very common to have only one SYSTEM chunk. 2. New SYSTEM bg will be allocated As btrfs_inc_block_group_ro() will check if we have enough space after marking current bg RO. If not, then allocate a new chunk. 3. New SYSTEM bg is still empty, will be reclaimed During the reclaim, we will mark it RO again. 4. That newly allocated empty SYSTEM bg get scrubbed We go back to step 2, as the bg is already mark RO but still not cleaned up yet. If the cleaner kthread doesn't get executed fast enough (e.g. only one CPU), then we will get more and more empty SYSTEM chunks, using up all the space of btrfs_super_block::sys_chunk_array. [FIX] Since scrub/dev-replace doesn't always need to allocate new extent, especially chunk tree extent, so we don't really need to do chunk pre-allocation. To break above spiral, here we introduce a new parameter to btrfs_inc_block_group(), @do_chunk_alloc, which indicates whether we need extra chunk pre-allocation. For relocation, we pass @do_chunk_alloc=true, while for scrub, we pass @do_chunk_alloc=false. This should keep unnecessary empty chunks from popping up for scrub. Also, since there are two parameters for btrfs_inc_block_group_ro(), add more comment for it. Reviewed-by: Filipe Manana <fdmanana@suse.com> Signed-off-by: Qu Wenruo <wqu@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
* | btrfs: change btrfs_fs_devices::rotating to boolJohannes Thumshirn2019-11-182-4/+4
| | | | | | | | | | | | | | | | | | | | | | | | | | | | struct btrfs_fs_devices::rotating currently is declared as an integer variable but only used as a boolean. Change the variable definition to bool and update to code touching it to set 'true' and 'false'. Reviewed-by: Qu Wenruo <wqu@suse.com> Reviewed-by: Anand Jain <anand.jain@oracle.com> Signed-off-by: Johannes Thumshirn <jthumshirn@suse.de> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
* | btrfs: change btrfs_fs_devices::seeding to boolJohannes Thumshirn2019-11-182-5/+5
| | | | | | | | | | | | | | | | | | | | | | | | | | | | struct btrfs_fs_devices::seeding currently is declared as an integer variable but only used as a boolean. Change the variable definition to bool and update to code touching it to set 'true' and 'false'. Reviewed-by: Qu Wenruo <wqu@suse.com> Reviewed-by: Anand Jain <anand.jain@oracle.com> Signed-off-by: Johannes Thumshirn <jthumshirn@suse.de> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
* | btrfs: rename btrfs_block_group_cacheDavid Sterba2019-11-1825-281/+266
| | | | | | | | | | | | | | | | | | | | The type name is misleading, a single entry is named 'cache' while this normally means a collection of objects. Rename that everywhere. Also the identifier was quite long, making function prototypes harder to format. Suggested-by: Nikolay Borisov <nborisov@suse.com> Reviewed-by: Qu Wenruo <wqu@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
* | btrfs: block-group: Reuse the item key from caller of read_one_block_group()Qu Wenruo2019-11-181-9/+8
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | For read_one_block_group(), its only caller has already got the item key to search next block group item. So we can use that key directly without doing our own convertion on stack. Also, since that key used in btrfs_read_block_groups() is vital for block group item search, add 'const' keyword for that parameter to prevent read_one_block_group() to modify it. Signed-off-by: Qu Wenruo <wqu@suse.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
* | btrfs: block-group: Refactor btrfs_read_block_groups()Qu Wenruo2019-11-181-111/+108
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Refactor the work inside the loop of btrfs_read_block_groups() into one separate function, read_one_block_group(). This allows read_one_block_group to be reused for later BG_TREE feature. The refactor does the following extra fix: - Use btrfs_fs_incompat() to replace open-coded feature check Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de> Reviewed-by: Anand Jain <anand.jain@oracle.com> Signed-off-by: Qu Wenruo <wqu@suse.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
* | btrfs: document extent buffer lockingDavid Sterba2019-11-181-14/+158
| | | | | | | | Signed-off-by: David Sterba <dsterba@suse.com>
* | btrfs: access eb::blocking_writers according to ACCESS_ONCE policiesDavid Sterba2019-11-181-11/+21
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | A nice writeup of the LKMM (Linux Kernel Memory Model) rules for access once policies can be found here https://lwn.net/Articles/799218/#Access-Marking%20Policies . The locked and unlocked access to eb::blocking_writers should be annotated accordingly, following this: Writes: - locked write must use ONCE, may use plain read - unlocked write must use ONCE Reads: - unlocked read must use ONCE - locked read may use plain read iff not mixed with unlocked read - unlocked read then locked must use ONCE There's one difference on the assembly level, where btrfs_tree_read_lock_atomic and btrfs_try_tree_read_lock used the cached value and did not reevaluate it after taking the lock. This could have missed some opportunities to take the lock in case blocking writers changed between the calls, but the window is just a few instructions long. As this is in try-lock, the callers handle that. Signed-off-by: David Sterba <dsterba@suse.com>