summaryrefslogtreecommitdiffstats
path: root/fs
Commit message (Collapse)AuthorAgeFilesLines
* btrfs: fix deadlock with fiemap and extent lockingJosef Bacik2024-02-191-17/+45
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | While working on the patchset to remove extent locking I got a lockdep splat with fiemap and pagefaulting with my new extent lock replacement lock. This deadlock exists with our normal code, we just don't have lockdep annotations with the extent locking so we've never noticed it. Since we're copying the fiemap extent to user space on every iteration we have the chance of pagefaulting. Because we hold the extent lock for the entire range we could mkwrite into a range in the file that we have mmap'ed. This would deadlock with the following stack trace [<0>] lock_extent+0x28d/0x2f0 [<0>] btrfs_page_mkwrite+0x273/0x8a0 [<0>] do_page_mkwrite+0x50/0xb0 [<0>] do_fault+0xc1/0x7b0 [<0>] __handle_mm_fault+0x2fa/0x460 [<0>] handle_mm_fault+0xa4/0x330 [<0>] do_user_addr_fault+0x1f4/0x800 [<0>] exc_page_fault+0x7c/0x1e0 [<0>] asm_exc_page_fault+0x26/0x30 [<0>] rep_movs_alternative+0x33/0x70 [<0>] _copy_to_user+0x49/0x70 [<0>] fiemap_fill_next_extent+0xc8/0x120 [<0>] emit_fiemap_extent+0x4d/0xa0 [<0>] extent_fiemap+0x7f8/0xad0 [<0>] btrfs_fiemap+0x49/0x80 [<0>] __x64_sys_ioctl+0x3e1/0xb50 [<0>] do_syscall_64+0x94/0x1a0 [<0>] entry_SYSCALL_64_after_hwframe+0x6e/0x76 I wrote an fstest to reproduce this deadlock without my replacement lock and verified that the deadlock exists with our existing locking. To fix this simply don't take the extent lock for the entire duration of the fiemap. This is safe in general because we keep track of where we are when we're searching the tree, so if an ordered extent updates in the middle of our fiemap call we'll still emit the correct extents because we know what offset we were on before. The only place we maintain the lock is searching delalloc. Since the delalloc stuff can change during writeback we want to lock the extent range so we have a consistent view of delalloc at the time we're checking to see if we need to set the delalloc flag. With this patch applied we no longer deadlock with my testcase. CC: stable@vger.kernel.org # 6.1+ Reviewed-by: Filipe Manana <fdmanana@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>
* btrfs: defrag: avoid unnecessary defrag caused by incorrect extent sizeQu Wenruo2024-02-191-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | [BUG] With the following file extent layout, defrag would do unnecessary IO and result more on-disk space usage. # mkfs.btrfs -f $dev # mount $dev $mnt # xfs_io -f -c "pwrite 0 40m" $mnt/foobar # sync # xfs_io -f -c "pwrite 40m 16k" $mnt/foobar # sync Above command would lead to the following file extent layout: item 6 key (257 EXTENT_DATA 0) itemoff 15816 itemsize 53 generation 7 type 1 (regular) extent data disk byte 298844160 nr 41943040 extent data offset 0 nr 41943040 ram 41943040 extent compression 0 (none) item 7 key (257 EXTENT_DATA 41943040) itemoff 15763 itemsize 53 generation 8 type 1 (regular) extent data disk byte 13631488 nr 16384 extent data offset 0 nr 16384 ram 16384 extent compression 0 (none) Which is mostly fine. We can allow the final 16K to be merged with the previous 40M, but it's upon the end users' preference. But if we defrag the file using the default parameters, it would result worse file layout: # btrfs filesystem defrag $mnt/foobar # sync item 6 key (257 EXTENT_DATA 0) itemoff 15816 itemsize 53 generation 7 type 1 (regular) extent data disk byte 298844160 nr 41943040 extent data offset 0 nr 8650752 ram 41943040 extent compression 0 (none) item 7 key (257 EXTENT_DATA 8650752) itemoff 15763 itemsize 53 generation 9 type 1 (regular) extent data disk byte 340787200 nr 33292288 extent data offset 0 nr 33292288 ram 33292288 extent compression 0 (none) item 8 key (257 EXTENT_DATA 41943040) itemoff 15710 itemsize 53 generation 8 type 1 (regular) extent data disk byte 13631488 nr 16384 extent data offset 0 nr 16384 ram 16384 extent compression 0 (none) Note the original 40M extent is still there, but a new 32M extent is created for no benefit at all. [CAUSE] There is an existing check to make sure we won't defrag a large enough extent (the threshold is by default 32M). But the check is using the length to the end of the extent: range_len = em->len - (cur - em->start); /* Skip too large extent */ if (range_len >= extent_thresh) goto next; This means, for the first 8MiB of the extent, the range_len is always smaller than the default threshold, and would not be defragged. But after the first 8MiB, the remaining part would fit the requirement, and be defragged. Such different behavior inside the same extent caused the above problem, and we should avoid different defrag decision inside the same extent. [FIX] Instead of using @range_len, just use @em->len, so that we have a consistent decision among the same file extent. Now with this fix, we won't touch the extent, thus not making it any worse. Reported-by: Filipe Manana <fdmanana@suse.com> Fixes: 0cb5950f3f3b ("btrfs: fix deadlock when reserving space during defrag") CC: stable@vger.kernel.org # 6.1+ Reviewed-by: Boris Burkov <boris@bur.io> Reviewed-by: Filipe Manana <fdmanana@suse.com> Signed-off-by: Qu Wenruo <wqu@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
* btrfs: don't refill whole delayed refs block reserve when starting transactionFilipe Manana2024-02-131-36/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Since commit 28270e25c69a ("btrfs: always reserve space for delayed refs when starting transaction") we started not only to reserve metadata space for the delayed refs a caller of btrfs_start_transaction() might generate but also to try to fully refill the delayed refs block reserve, because there are several case where we generate delayed refs and haven't reserved space for them, relying on the global block reserve. Relying too much on the global block reserve is not always safe, and can result in hitting -ENOSPC during transaction commits or worst, in rare cases, being unable to mount a filesystem that needs to do orphan cleanup or anything that requires modifying the filesystem during mount, and has no more unallocated space and the metadata space is nearly full. This was explained in detail in that commit's change log. However the gap between the reserved amount and the size of the delayed refs block reserve can be huge, so attempting to reserve space for such a gap can result in allocating many metadata block groups that end up not being used. After a recent patch, with the subject: "btrfs: add new unused block groups to the list of unused block groups" We started to add new block groups that are unused to the list of unused block groups, to avoid having them around for a very long time in case they are never used, because a block group is only added to the list of unused block groups when we deallocate the last extent or when mounting the filesystem and the block group has 0 bytes used. This is not a problem introduced by the commit mentioned earlier, it always existed as our metadata space reservations are, most of the time, pessimistic and end up not using all the space they reserved, so we can occasionally end up with one or two unused metadata block groups for a long period. However after that commit mentioned earlier, we are just more pessimistic in the metadata space reservations when starting a transaction and therefore the issue is more likely to happen. This however is not always enough because we might create unused metadata block groups when reserving metadata space at a high rate if there's always a gap in the delayed refs block reserve and the cleaner kthread isn't triggered often enough or is busy with other work (running delayed iputs, cleaning deleted roots, etc), not to mention the block group's allocated space is only usable for a new block group after the transaction used to remove it is committed. A user reported that he's getting a lot of allocated metadata block groups but the usage percentage of metadata space was very low compared to the total allocated space, specially after running a series of block group relocations. So for now stop trying to refill the gap in the delayed refs block reserve and reserve space only for the delayed refs we are expected to generate when starting a transaction. CC: stable@vger.kernel.org # 6.7+ Reported-by: Ivan Shapovalov <intelfx@intelfx.name> Link: https://lore.kernel.org/linux-btrfs/9cdbf0ca9cdda1b4c84e15e548af7d7f9f926382.camel@intelfx.name/ Link: https://lore.kernel.org/linux-btrfs/CAL3q7H6802ayLHUJFztzZAVzBLJAGdFx=6FHNNy87+obZXXZpQ@mail.gmail.com/ Tested-by: Ivan Shapovalov <intelfx@intelfx.name> Reported-by: Heddxh <g311571057@gmail.com> Link: https://lore.kernel.org/linux-btrfs/CAE93xANEby6RezOD=zcofENYZOT-wpYygJyauyUAZkLv6XVFOA@mail.gmail.com/ Reviewed-by: Josef Bacik <josef@toxicpanda.com> Signed-off-by: Filipe Manana <fdmanana@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
* btrfs: zoned: fix chunk map leak when loading block group zone infoFilipe Manana2024-02-131-0/+1
| | | | | | | | | | | | | | | At btrfs_load_block_group_zone_info() we never drop a reference on the chunk map we have looked up, therefore leaking a reference on it. So add the missing btrfs_free_chunk_map() at the end of the function. Fixes: 7dc66abb5a47 ("btrfs: use a dedicated data structure for chunk maps") Reported-by: Johannes Thumshirn <johannes.thumshirn@wdc.com> Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com> Tested-by: Johannes Thumshirn <johannes.thumshirn@wdc.com> Reviewed-by: Anand Jain <anand.jain@oracle.com> Signed-off-by: Filipe Manana <fdmanana@suse.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
* btrfs: reject encoded write if inode has nodatasum flag setFilipe Manana2024-02-131-0/+7
| | | | | | | | | | | | | | | | | | | | | | | | | | | | Currently we allow an encoded write against inodes that have the NODATASUM flag set, either because they are NOCOW files or they were created while the filesystem was mounted with "-o nodatasum". This results in having compressed extents without corresponding checksums, which is a filesystem inconsistency reported by 'btrfs check'. For example, running btrfs/281 with MOUNT_OPTIONS="-o nodatacow" triggers this and 'btrfs check' errors out with: [1/7] checking root items [2/7] checking extents [3/7] checking free space tree [4/7] checking fs roots root 256 inode 257 errors 1040, bad file extent, some csum missing root 256 inode 258 errors 1040, bad file extent, some csum missing ERROR: errors found in fs roots (...) So reject encoded writes if the target inode has NODATASUM set. CC: stable@vger.kernel.org # 6.1+ 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>
* btrfs: don't reserve space for checksums when writing to nocow filesFilipe Manana2024-02-131-10/+19
| | | | | | | | | | | | | | | | | | | Currently when doing a write to a file we always reserve metadata space for inserting data checksums. However we don't need to do it if we have a nodatacow file (-o nodatacow mount option or chattr +C) or if checksums are disabled (-o nodatasum mount option), as in that case we are only adding unnecessary pressure to metadata reservations. For example on x86_64, with the default node size of 16K, a 4K buffered write into a nodatacow file is reserving 655360 bytes of metadata space, as it's accounting for checksums. After this change, which stops reserving space for checksums if we have a nodatacow file or checksums are disabled, we only need to reserve 393216 bytes of metadata. CC: stable@vger.kernel.org # 6.1+ Signed-off-by: Filipe Manana <fdmanana@suse.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
* btrfs: add new unused block groups to the list of unused block groupsFilipe Manana2024-02-091-0/+31
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Space reservations for metadata are, most of the time, pessimistic as we reserve space for worst possible cases - where tree heights are at the maximum possible height (8), we need to COW every extent buffer in a tree path, need to split extent buffers, etc. For data, we generally reserve the exact amount of space we are going to allocate. The exception here is when using compression, in which case we reserve space matching the uncompressed size, as the compression only happens at writeback time and in the worst possible case we need that amount of space in case the data is not compressible. This means that when there's not available space in the corresponding space_info object, we may need to allocate a new block group, and then that block group might not be used after all. In this case the block group is never added to the list of unused block groups and ends up never being deleted - except if we unmount and mount again the fs, as when reading block groups from disk we add unused ones to the list of unused block groups (fs_info->unused_bgs). Otherwise a block group is only added to the list of unused block groups when we deallocate the last extent from it, so if no extent is ever allocated, the block group is kept around forever. This also means that if we have a bunch of tasks reserving space in parallel we can end up allocating many block groups that end up never being used or kept around for too long without being used, which has the potential to result in ENOSPC failures in case for example we over allocate too many metadata block groups and then end up in a state without enough unallocated space to allocate a new data block group. This is more likely to happen with metadata reservations as of kernel 6.7, namely since commit 28270e25c69a ("btrfs: always reserve space for delayed refs when starting transaction"), because we started to always reserve space for delayed references when starting a transaction handle for a non-zero number of items, and also to try to reserve space to fill the gap between the delayed block reserve's reserved space and its size. So to avoid this, when finishing the creation a new block group, add the block group to the list of unused block groups if it's still unused at that time. This way the next time the cleaner kthread runs, it will delete the block group if it's still unused and not needed to satisfy existing space reservations. Reported-by: Ivan Shapovalov <intelfx@intelfx.name> Link: https://lore.kernel.org/linux-btrfs/9cdbf0ca9cdda1b4c84e15e548af7d7f9f926382.camel@intelfx.name/ CC: stable@vger.kernel.org # 6.7+ Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com> Reviewed-by: Josef Bacik <josef@toxicpanda.com> Reviewed-by: Boris Burkov <boris@bur.io> Signed-off-by: Filipe Manana <fdmanana@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
* btrfs: do not delete unused block group if it may be used soonFilipe Manana2024-02-091-0/+46
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Before deleting a block group that is in the list of unused block groups (fs_info->unused_bgs), we check if the block group became used before deleting it, as extents from it may have been allocated after it was added to the list. However even if the block group was not yet used, there may be tasks that have only reserved space and have not yet allocated extents, and they might be relying on the availability of the unused block group in order to allocate extents. The reservation works first by increasing the "bytes_may_use" field of the corresponding space_info object (which may first require flushing delayed items, allocating a new block group, etc), and only later a task does the actual allocation of extents. For metadata we usually don't end up using all reserved space, as we are pessimistic and typically account for the worst cases (need to COW every single node in a path of a tree at maximum possible height, etc). For data we usually reserve the exact amount of space we're going to allocate later, except when using compression where we always reserve space based on the uncompressed size, as compression is only triggered when writeback starts so we don't know in advance how much space we'll actually need, or if the data is compressible. So don't delete an unused block group if the total size of its space_info object minus the block group's size is less then the sum of used space and space that may be used (space_info->bytes_may_use), as that means we have tasks that reserved space and may need to allocate extents from the block group. In this case, besides skipping the deletion, re-add the block group to the list of unused block groups so that it may be reconsidered later, in case the tasks that reserved space end up not needing to allocate extents from it. Allowing the deletion of the block group while we have reserved space, can result in tasks failing to allocate metadata extents (-ENOSPC) while under a transaction handle, resulting in a transaction abort, or failure during writeback for the case of data extents. CC: stable@vger.kernel.org # 6.0+ Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com> Reviewed-by: Josef Bacik <josef@toxicpanda.com> Reviewed-by: Boris Burkov <boris@bur.io> Signed-off-by: Filipe Manana <fdmanana@suse.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
* btrfs: add and use helper to check if block group is usedFilipe Manana2024-02-092-2/+8
| | | | | | | | | | | | | Add a helper function to determine if a block group is being used and make use of it at btrfs_delete_unused_bgs(). This helper will also be used in future code changes. Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com> Reviewed-by: Josef Bacik <josef@toxicpanda.com> Reviewed-by: Boris Burkov <boris@bur.io> Signed-off-by: Filipe Manana <fdmanana@suse.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
* btrfs: don't drop extent_map for free space inode on write errorJosef Bacik2024-02-091-2/+17
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | While running the CI for an unrelated change I hit the following panic with generic/648 on btrfs_holes_spacecache. assertion failed: block_start != EXTENT_MAP_HOLE, in fs/btrfs/extent_io.c:1385 ------------[ cut here ]------------ kernel BUG at fs/btrfs/extent_io.c:1385! invalid opcode: 0000 [#1] PREEMPT SMP NOPTI CPU: 1 PID: 2695096 Comm: fsstress Kdump: loaded Tainted: G W 6.8.0-rc2+ #1 RIP: 0010:__extent_writepage_io.constprop.0+0x4c1/0x5c0 Call Trace: <TASK> extent_write_cache_pages+0x2ac/0x8f0 extent_writepages+0x87/0x110 do_writepages+0xd5/0x1f0 filemap_fdatawrite_wbc+0x63/0x90 __filemap_fdatawrite_range+0x5c/0x80 btrfs_fdatawrite_range+0x1f/0x50 btrfs_write_out_cache+0x507/0x560 btrfs_write_dirty_block_groups+0x32a/0x420 commit_cowonly_roots+0x21b/0x290 btrfs_commit_transaction+0x813/0x1360 btrfs_sync_file+0x51a/0x640 __x64_sys_fdatasync+0x52/0x90 do_syscall_64+0x9c/0x190 entry_SYSCALL_64_after_hwframe+0x6e/0x76 This happens because we fail to write out the free space cache in one instance, come back around and attempt to write it again. However on the second pass through we go to call btrfs_get_extent() on the inode to get the extent mapping. Because this is a new block group, and with the free space inode we always search the commit root to avoid deadlocking with the tree, we find nothing and return a EXTENT_MAP_HOLE for the requested range. This happens because the first time we try to write the space cache out we hit an error, and on an error we drop the extent mapping. This is normal for normal files, but the free space cache inode is special. We always expect the extent map to be correct. Thus the second time through we end up with a bogus extent map. Since we're deprecating this feature, the most straightforward way to fix this is to simply skip dropping the extent map range for this failed range. I shortened the test by using error injection to stress the area to make it easier to reproduce. With this patch in place we no longer panic with my error injection test. CC: stable@vger.kernel.org # 4.14+ Reviewed-by: Filipe Manana <fdmanana@suse.com> Signed-off-by: Josef Bacik <josef@toxicpanda.com> Signed-off-by: David Sterba <dsterba@suse.com>
* btrfs: do not ASSERT() if the newly created subvolume already got readQu Wenruo2024-01-311-2/+11
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | [BUG] There is a syzbot crash, triggered by the ASSERT() during subvolume creation: assertion failed: !anon_dev, in fs/btrfs/disk-io.c:1319 ------------[ cut here ]------------ kernel BUG at fs/btrfs/disk-io.c:1319! invalid opcode: 0000 [#1] PREEMPT SMP KASAN RIP: 0010:btrfs_get_root_ref.part.0+0x9aa/0xa60 <TASK> btrfs_get_new_fs_root+0xd3/0xf0 create_subvol+0xd02/0x1650 btrfs_mksubvol+0xe95/0x12b0 __btrfs_ioctl_snap_create+0x2f9/0x4f0 btrfs_ioctl_snap_create+0x16b/0x200 btrfs_ioctl+0x35f0/0x5cf0 __x64_sys_ioctl+0x19d/0x210 do_syscall_64+0x3f/0xe0 entry_SYSCALL_64_after_hwframe+0x63/0x6b ---[ end trace 0000000000000000 ]--- [CAUSE] During create_subvol(), after inserting root item for the newly created subvolume, we would trigger btrfs_get_new_fs_root() to get the btrfs_root of that subvolume. The idea here is, we have preallocated an anonymous device number for the subvolume, thus we can assign it to the new subvolume. But there is really nothing preventing things like backref walk to read the new subvolume. If that happens before we call btrfs_get_new_fs_root(), the subvolume would be read out, with a new anonymous device number assigned already. In that case, we would trigger ASSERT(), as we really expect no one to read out that subvolume (which is not yet accessible from the fs). But things like backref walk is still possible to trigger the read on the subvolume. Thus our assumption on the ASSERT() is not correct in the first place. [FIX] Fix it by removing the ASSERT(), and just free the @anon_dev, reset it to 0, and continue. If the subvolume tree is read out by something else, it should have already get a new anon_dev assigned thus we only need to free the preallocated one. Reported-by: Chenyuan Yang <chenyuan0y@gmail.com> Fixes: 2dfb1e43f57d ("btrfs: preallocate anon block device at first phase of snapshot creation") CC: stable@vger.kernel.org # 5.15+ Reviewed-by: Filipe Manana <fdmanana@suse.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: forbid deleting live subvol qgroupBoris Burkov2024-01-311-0/+14
| | | | | | | | | | | | | If a subvolume still exists, forbid deleting its qgroup 0/subvolid. This behavior generally leads to incorrect behavior in squotas and doesn't have a legitimate purpose. Fixes: cecbb533b5fc ("btrfs: record simple quota deltas in delayed refs") CC: stable@vger.kernel.org # 5.4+ Reviewed-by: Qu Wenruo <wqu@suse.com> Signed-off-by: Boris Burkov <boris@bur.io> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
* btrfs: forbid creating subvol qgroupsBoris Burkov2024-01-311-0/+5
| | | | | | | | | | | | | | | Creating a qgroup 0/subvolid leads to various races and it isn't helpful, because you can't specify a subvol id when creating a subvol, so you can't be sure it will be the right one. Any requirements on the automatic subvol can be gratified by using a higher level qgroup and the inheritance parameters of subvol creation. Fixes: cecbb533b5fc ("btrfs: record simple quota deltas in delayed refs") CC: stable@vger.kernel.org # 4.14+ Reviewed-by: Qu Wenruo <wqu@suse.com> Signed-off-by: Boris Burkov <boris@bur.io> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
* btrfs: send: return EOPNOTSUPP on unknown flagsDavid Sterba2024-01-311-1/+1
| | | | | | | | | | | | | When some ioctl flags are checked we return EOPNOTSUPP, like for BTRFS_SCRUB_SUPPORTED_FLAGS, BTRFS_SUBVOL_CREATE_ARGS_MASK or fallocate modes. The EINVAL is supposed to be for a supported but invalid values or combination of options. Fix that when checking send flags so it's consistent with the rest. CC: stable@vger.kernel.org # 4.14+ Link: https://lore.kernel.org/linux-btrfs/CAL3q7H5rryOLzp3EKq8RTbjMHMHeaJubfpsVLF6H4qJnKCUR1w@mail.gmail.com/ Reviewed-by: Filipe Manana <fdmanana@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
* btrfs: scrub: limit RST scrub to chunk boundaryQu Wenruo2024-01-181-0/+7
| | | | | | | | | | | | | | | | | | | | | | | [BUG] If there is an extent beyond chunk boundary, currently RST scrub would error out. [CAUSE] In scrub_submit_extent_sector_read(), we completely rely on extent_sector_bitmap, which is populated using extent tree. The extent tree can be corrupted that there is an extent item beyond a chunk. In that case, RST scrub would fail and error out. [FIX] Despite the extent_sector_bitmap usage, also limit the read to chunk boundary. Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com> Signed-off-by: Qu Wenruo <wqu@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
* btrfs: scrub: avoid use-after-free when chunk length is not 64K alignedQu Wenruo2024-01-181-7/+22
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | [BUG] There is a bug report that, on a ext4-converted btrfs, scrub leads to various problems, including: - "unable to find chunk map" errors BTRFS info (device vdb): scrub: started on devid 1 BTRFS critical (device vdb): unable to find chunk map for logical 2214744064 length 4096 BTRFS critical (device vdb): unable to find chunk map for logical 2214744064 length 45056 This would lead to unrepariable errors. - Use-after-free KASAN reports: ================================================================== BUG: KASAN: slab-use-after-free in __blk_rq_map_sg+0x18f/0x7c0 Read of size 8 at addr ffff8881013c9040 by task btrfs/909 CPU: 0 PID: 909 Comm: btrfs Not tainted 6.7.0-x64v3-dbg #11 c50636e9419a8354555555245df535e380563b2b Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 2023.11-2 12/24/2023 Call Trace: <TASK> dump_stack_lvl+0x43/0x60 print_report+0xcf/0x640 kasan_report+0xa6/0xd0 __blk_rq_map_sg+0x18f/0x7c0 virtblk_prep_rq.isra.0+0x215/0x6a0 [virtio_blk 19a65eeee9ae6fcf02edfad39bb9ddee07dcdaff] virtio_queue_rqs+0xc4/0x310 [virtio_blk 19a65eeee9ae6fcf02edfad39bb9ddee07dcdaff] blk_mq_flush_plug_list.part.0+0x780/0x860 __blk_flush_plug+0x1ba/0x220 blk_finish_plug+0x3b/0x60 submit_initial_group_read+0x10a/0x290 [btrfs e57987a360bed82fe8756dcd3e0de5406ccfe965] flush_scrub_stripes+0x38e/0x430 [btrfs e57987a360bed82fe8756dcd3e0de5406ccfe965] scrub_stripe+0x82a/0xae0 [btrfs e57987a360bed82fe8756dcd3e0de5406ccfe965] scrub_chunk+0x178/0x200 [btrfs e57987a360bed82fe8756dcd3e0de5406ccfe965] scrub_enumerate_chunks+0x4bc/0xa30 [btrfs e57987a360bed82fe8756dcd3e0de5406ccfe965] btrfs_scrub_dev+0x398/0x810 [btrfs e57987a360bed82fe8756dcd3e0de5406ccfe965] btrfs_ioctl+0x4b9/0x3020 [btrfs e57987a360bed82fe8756dcd3e0de5406ccfe965] __x64_sys_ioctl+0xbd/0x100 do_syscall_64+0x5d/0xe0 entry_SYSCALL_64_after_hwframe+0x63/0x6b RIP: 0033:0x7f47e5e0952b - Crash, mostly due to above use-after-free [CAUSE] The converted fs has the following data chunk layout: item 2 key (FIRST_CHUNK_TREE CHUNK_ITEM 2214658048) itemoff 16025 itemsize 80 length 86016 owner 2 stripe_len 65536 type DATA|single For above logical bytenr 2214744064, it's at the chunk end (2214658048 + 86016 = 2214744064). This means btrfs_submit_bio() would split the bio, and trigger endio function for both of the two halves. However scrub_submit_initial_read() would only expect the endio function to be called once, not any more. This means the first endio function would already free the bbio::bio, leaving the bvec freed, thus the 2nd endio call would lead to use-after-free. [FIX] - Make sure scrub_read_endio() only updates bits in its range Since we may read less than 64K at the end of the chunk, we should not touch the bits beyond chunk boundary. - Make sure scrub_submit_initial_read() only to read the chunk range This is done by calculating the real number of sectors we need to read, and add sector-by-sector to the bio. Thankfully the scrub read repair path won't need extra fixes: - scrub_stripe_submit_repair_read() With above fixes, we won't update error bit for range beyond chunk, thus scrub_stripe_submit_repair_read() should never submit any read beyond the chunk. Reported-by: Rongrong <i@rong.moe> Fixes: e02ee89baa66 ("btrfs: scrub: switch scrub_simple_mirror() to scrub_stripe infrastructure") Tested-by: Rongrong <i@rong.moe> Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com> Signed-off-by: Qu Wenruo <wqu@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
* btrfs: don't unconditionally call folio_start_writeback in subpageJosef Bacik2024-01-181-1/+2
| | | | | | | | | | | | | | | | | | | | | In the normal case we check if a page is under writeback and skip it before we attempt to begin writeback. The exception is subpage metadata writes, where we know we don't have an eb under writeback and we're doing it one eb at a time. Since b5612c368648 ("mm: return void from folio_start_writeback() and related functions") we now will BUG_ON() if we call folio_start_writeback() on a folio that's already under writeback. Previously folio_start_writeback() would bail if writeback was already started. Fix this in the subpage code by checking if we have writeback set and skipping it if we do. This fixes the panic we were seeing on subpage. Reviewed-by: Qu Wenruo <wqu@suse.com> Reviewed-by: Anand Jain <anand.jain@oracle.com> Signed-off-by: Josef Bacik <josef@toxicpanda.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
* btrfs: use the original mount's mount options for the legacy reconfigureJosef Bacik2024-01-181-0/+8
| | | | | | | | | | | | | | | | | | | | | | btrfs/330, which tests our old trick to allow mount -o ro,subvol=/x /dev/sda1 /foo mount -o rw,subvol=/y /dev/sda1 /bar fails on the block group tree. This is because we aren't preserving the mount options for what is essentially a remount, and thus we're ending up without the FREE_SPACE_TREE mount option, which triggers our free space tree delete codepath. This isn't possible with the block group tree and thus it falls over. Fix this by making sure we copy the existing mount options for the existing fs mount over in this case. Fixes: f044b318675f ("btrfs: handle the ro->rw transition for mounting different subvolumes") Reviewed-by: Neal Gompa <neal@gompa.dev> Signed-off-by: Josef Bacik <josef@toxicpanda.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
* btrfs: don't warn if discard range is not aligned to sectorDavid Sterba2024-01-181-1/+2
| | | | | | | | | | | | | | There's a warning in btrfs_issue_discard() when the range is not aligned to 512 bytes, originally added in 4d89d377bbb0 ("btrfs: btrfs_issue_discard ensure offset/length are aligned to sector boundaries"). We can't do sub-sector writes anyway so the adjustment is the only thing that we can do and the warning is unnecessary. CC: stable@vger.kernel.org # 4.19+ Reported-by: syzbot+4a4f1eba14eb5c3417d1@syzkaller.appspotmail.com Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com> Reviewed-by: Anand Jain <anand.jain@oracle.com> Signed-off-by: David Sterba <dsterba@suse.com>
* btrfs: tree-checker: fix inline ref size in error messagesChung-Chiang Cheng2024-01-181-1/+1
| | | | | | | | | | | | | The error message should accurately reflect the size rather than the type. Fixes: f82d1c7ca8ae ("btrfs: tree-checker: Add EXTENT_ITEM and METADATA_ITEM check") CC: stable@vger.kernel.org # 5.4+ Reviewed-by: Filipe Manana <fdmanana@suse.com> Reviewed-by: Qu Wenruo <wqu@suse.com> Signed-off-by: Chung-Chiang Cheng <cccheng@synology.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
* btrfs: zstd: fix and simplify the inline extent decompressionQu Wenruo2024-01-182-54/+23
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | [BUG] If we have a filesystem with 4k sectorsize, and an inlined compressed extent created like this: item 4 key (257 INODE_ITEM 0) itemoff 15863 itemsize 160 generation 8 transid 8 size 4096 nbytes 4096 block group 0 mode 100600 links 1 uid 0 gid 0 rdev 0 sequence 1 flags 0x0(none) item 5 key (257 INODE_REF 256) itemoff 15839 itemsize 24 index 2 namelen 14 name: source_inlined item 6 key (257 EXTENT_DATA 0) itemoff 15770 itemsize 69 generation 8 type 0 (inline) inline extent data size 48 ram_bytes 4096 compression 3 (zstd) Then trying to reflink that extent in an aarch64 system with 64K page size, the reflink would just fail: # xfs_io -f -c "reflink $mnt/source_inlined 0 60k 4k" $mnt/dest XFS_IOC_CLONE_RANGE: Input/output error [CAUSE] In zstd_decompress(), we didn't treat @start_byte as just a page offset, but also use it as an indicator on whether we should error out, without any proper explanation (this is copied from other decompression code). In reality, for subpage cases, although @start_byte can be non-zero, we should never switch input/output buffer nor error out, since the whole input/output buffer should never exceed one sector, thus we should not need to do any buffer switch. Thus the current code using @start_byte as a condition to switch input/output buffer or finish the decompression is completely incorrect. [FIX] The fix involves several modification: - Rename @start_byte to @dest_pgoff to properly express its meaning - Use @sectorsize other than PAGE_SIZE to properly initialize the output buffer size - Use correct destination offset inside the destination page - Simplify the main loop Since the input/output buffer should never switch, we only need one zstd_decompress_stream() call. - Consider early end as an error After the fix, even on 64K page sized aarch64, above reflink now works as expected: # xfs_io -f -c "reflink $mnt/source_inlined 0 60k 4k" $mnt/dest linked 4096/4096 bytes at offset 61440 And results the correct file layout: item 9 key (258 INODE_ITEM 0) itemoff 15542 itemsize 160 generation 10 transid 10 size 65536 nbytes 4096 block group 0 mode 100600 links 1 uid 0 gid 0 rdev 0 sequence 1 flags 0x0(none) item 10 key (258 INODE_REF 256) itemoff 15528 itemsize 14 index 3 namelen 4 name: dest item 11 key (258 XATTR_ITEM 3817753667) itemoff 15445 itemsize 83 location key (0 UNKNOWN.0 0) type XATTR transid 10 data_len 37 name_len 16 name: security.selinux data unconfined_u:object_r:unlabeled_t:s0 item 12 key (258 EXTENT_DATA 61440) itemoff 15392 itemsize 53 generation 10 type 1 (regular) extent data disk byte 13631488 nr 4096 extent data offset 0 nr 4096 ram 4096 extent compression 0 (none) Signed-off-by: Qu Wenruo <wqu@suse.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
* btrfs: lzo: fix and simplify the inline extent decompressionQu Wenruo2024-01-182-26/+10
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | [BUG] If we have a filesystem with 4k sectorsize, and an inlined compressed extent created like this: item 4 key (257 INODE_ITEM 0) itemoff 15863 itemsize 160 generation 8 transid 8 size 4096 nbytes 4096 block group 0 mode 100600 links 1 uid 0 gid 0 rdev 0 sequence 1 flags 0x0(none) item 5 key (257 INODE_REF 256) itemoff 15839 itemsize 24 index 2 namelen 14 name: source_inlined item 6 key (257 EXTENT_DATA 0) itemoff 15770 itemsize 69 generation 8 type 0 (inline) inline extent data size 48 ram_bytes 4096 compression 2 (lzo) Then trying to reflink that extent in an aarch64 system with 64K page size, the reflink would just fail: # xfs_io -f -c "reflink $mnt/source_inlined 0 60k 4k" $mnt/dest XFS_IOC_CLONE_RANGE: Input/output error [CAUSE] In zlib_decompress(), we didn't treat @start_byte as just a page offset, but also use it as an indicator on whether we should error out, without any proper explanation (this is from the very beginning of btrfs). In reality, for subpage cases, although @start_byte can be non-zero, we should never switch input/output buffer nor error out, since the whole input/output buffer should never exceed one sector. Note: The above assumption is only not true if we're going to support multi-page sectorsize. Thus the current code using @start_byte as a condition to switch input/output buffer or finish the decompression is completely incorrect. [FIX] The fix involves several modifications: - Rename @start_byte to @dest_pgoff to properly express its meaning - Use @sectorsize other than PAGE_SIZE to properly initialize the output buffer size - Use correct destination offset inside the destination page - Use memcpy_to_page() to copy the contents to the destination page - Use memzero_page() to zero out the tailing part - Consider early end as an error After the fix, even on 64K page sized aarch64, above reflink now works as expected: # xfs_io -f -c "reflink $mnt/source_inlined 0 60k 4k" $mnt/dest linked 4096/4096 bytes at offset 61440 And results the correct file layout: item 9 key (258 INODE_ITEM 0) itemoff 15542 itemsize 160 generation 10 transid 10 size 65536 nbytes 4096 block group 0 mode 100600 links 1 uid 0 gid 0 rdev 0 sequence 1 flags 0x0(none) item 10 key (258 INODE_REF 256) itemoff 15528 itemsize 14 index 3 namelen 4 name: dest item 11 key (258 XATTR_ITEM 3817753667) itemoff 15445 itemsize 83 location key (0 UNKNOWN.0 0) type XATTR transid 10 data_len 37 name_len 16 name: security.selinux data unconfined_u:object_r:unlabeled_t:s0 item 12 key (258 EXTENT_DATA 61440) itemoff 15392 itemsize 53 generation 10 type 1 (regular) extent data disk byte 13631488 nr 4096 extent data offset 0 nr 4096 ram 4096 extent compression 0 (none) Signed-off-by: Qu Wenruo <wqu@suse.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
* btrfs: zlib: fix and simplify the inline extent decompressionQu Wenruo2024-01-183-62/+36
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | [BUG] If we have a filesystem with 4k sectorsize, and an inlined compressed extent created like this: item 4 key (257 INODE_ITEM 0) itemoff 15863 itemsize 160 generation 8 transid 8 size 4096 nbytes 4096 block group 0 mode 100600 links 1 uid 0 gid 0 rdev 0 sequence 1 flags 0x0(none) item 5 key (257 INODE_REF 256) itemoff 15839 itemsize 24 index 2 namelen 14 name: source_inlined item 6 key (257 EXTENT_DATA 0) itemoff 15770 itemsize 69 generation 8 type 0 (inline) inline extent data size 48 ram_bytes 4096 compression 1 (zlib) Which has an inline compressed extent at file offset 0, and its decompressed size is 4K, allowing us to reflink that 4K range to another location (which will not be compressed). If we do such reflink on a subpage system, it would fail like this: # xfs_io -f -c "reflink $mnt/source_inlined 0 60k 4k" $mnt/dest XFS_IOC_CLONE_RANGE: Input/output error [CAUSE] In zlib_decompress(), we didn't treat @start_byte as just a page offset, but also use it as an indicator on whether we should switch our output buffer. In reality, for subpage cases, although @start_byte can be non-zero, we should never switch input/output buffer, since the whole input/output buffer should never exceed one sector. Note: The above assumption is only not true if we're going to support multi-page sectorsize. Thus the current code using @start_byte as a condition to switch input/output buffer or finish the decompression is completely incorrect. [FIX] The fix involves several modifications: - Rename @start_byte to @dest_pgoff to properly express its meaning - Add an extra ASSERT() inside btrfs_decompress() to make sure the input/output size never exceeds one sector. - Use Z_FINISH flag to make sure the decompression happens in one go - Remove the loop needed to switch input/output buffers - Use correct destination offset inside the destination page - Consider early end as an error After the fix, even on 64K page sized aarch64, above reflink now works as expected: # xfs_io -f -c "reflink $mnt/source_inlined 0 60k 4k" $mnt/dest linked 4096/4096 bytes at offset 61440 And resulted a correct file layout: item 9 key (258 INODE_ITEM 0) itemoff 15542 itemsize 160 generation 10 transid 10 size 65536 nbytes 4096 block group 0 mode 100600 links 1 uid 0 gid 0 rdev 0 sequence 1 flags 0x0(none) item 10 key (258 INODE_REF 256) itemoff 15528 itemsize 14 index 3 namelen 4 name: dest item 11 key (258 XATTR_ITEM 3817753667) itemoff 15445 itemsize 83 location key (0 UNKNOWN.0 0) type XATTR transid 10 data_len 37 name_len 16 name: security.selinux data unconfined_u:object_r:unlabeled_t:s0 item 12 key (258 EXTENT_DATA 61440) itemoff 15392 itemsize 53 generation 10 type 1 (regular) extent data disk byte 13631488 nr 4096 extent data offset 0 nr 4096 ram 4096 extent compression 0 (none) Signed-off-by: Qu Wenruo <wqu@suse.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
* btrfs: defrag: reject unknown flags of btrfs_ioctl_defrag_range_argsQu Wenruo2024-01-121-0/+4
| | | | | | | | | | | | | | | | | Add extra sanity check for btrfs_ioctl_defrag_range_args::flags. This is not really to enhance fuzzing tests, but as a preparation for future expansion on btrfs_ioctl_defrag_range_args. In the future we're going to add new members, allowing more fine tuning for btrfs defrag. Without the -ENONOTSUPP error, there would be no way to detect if the kernel supports those new defrag features. CC: stable@vger.kernel.org # 4.14+ Reviewed-by: Filipe Manana <fdmanana@suse.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: avoid copying BTRFS_ROOT_SUBVOL_DEAD flag to snapshot of subvolume ↵Omar Sandoval2024-01-121-9/+13
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | being deleted Sweet Tea spotted a race between subvolume deletion and snapshotting that can result in the root item for the snapshot having the BTRFS_ROOT_SUBVOL_DEAD flag set. The race is: Thread 1 | Thread 2 ----------------------------------------------|---------- btrfs_delete_subvolume | btrfs_set_root_flags(BTRFS_ROOT_SUBVOL_DEAD)| |btrfs_mksubvol | down_read(subvol_sem) | create_snapshot | ... | create_pending_snapshot | copy root item from source down_write(subvol_sem) | This flag is only checked in send and swap activate, which this would cause to fail mysteriously. create_snapshot() now checks the root refs to reject a deleted subvolume, so we can fix this by locking subvol_sem earlier so that the BTRFS_ROOT_SUBVOL_DEAD flag and the root refs are updated atomically. CC: stable@vger.kernel.org # 4.14+ Reported-by: Sweet Tea Dorminy <sweettea-kernel@dorminy.me> Reviewed-by: Sweet Tea Dorminy <sweettea-kernel@dorminy.me> Reviewed-by: Anand Jain <anand.jain@oracle.com> Signed-off-by: Omar Sandoval <osandov@fb.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
* btrfs: don't abort filesystem when attempting to snapshot deleted subvolumeOmar Sandoval2024-01-121-0/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | If the source file descriptor to the snapshot ioctl refers to a deleted subvolume, we get the following abort: BTRFS: Transaction aborted (error -2) WARNING: CPU: 0 PID: 833 at fs/btrfs/transaction.c:1875 create_pending_snapshot+0x1040/0x1190 [btrfs] Modules linked in: pata_acpi btrfs ata_piix libata scsi_mod virtio_net blake2b_generic xor net_failover virtio_rng failover scsi_common rng_core raid6_pq libcrc32c CPU: 0 PID: 833 Comm: t_snapshot_dele Not tainted 6.7.0-rc6 #2 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.16.3-1.fc39 04/01/2014 RIP: 0010:create_pending_snapshot+0x1040/0x1190 [btrfs] RSP: 0018:ffffa09c01337af8 EFLAGS: 00010282 RAX: 0000000000000000 RBX: ffff9982053e7c78 RCX: 0000000000000027 RDX: ffff99827dc20848 RSI: 0000000000000001 RDI: ffff99827dc20840 RBP: ffffa09c01337c00 R08: 0000000000000000 R09: ffffa09c01337998 R10: 0000000000000003 R11: ffffffffb96da248 R12: fffffffffffffffe R13: ffff99820535bb28 R14: ffff99820b7bd000 R15: ffff99820381ea80 FS: 00007fe20aadabc0(0000) GS:ffff99827dc00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000559a120b502f CR3: 00000000055b6000 CR4: 00000000000006f0 Call Trace: <TASK> ? create_pending_snapshot+0x1040/0x1190 [btrfs] ? __warn+0x81/0x130 ? create_pending_snapshot+0x1040/0x1190 [btrfs] ? report_bug+0x171/0x1a0 ? handle_bug+0x3a/0x70 ? exc_invalid_op+0x17/0x70 ? asm_exc_invalid_op+0x1a/0x20 ? create_pending_snapshot+0x1040/0x1190 [btrfs] ? create_pending_snapshot+0x1040/0x1190 [btrfs] create_pending_snapshots+0x92/0xc0 [btrfs] btrfs_commit_transaction+0x66b/0xf40 [btrfs] btrfs_mksubvol+0x301/0x4d0 [btrfs] btrfs_mksnapshot+0x80/0xb0 [btrfs] __btrfs_ioctl_snap_create+0x1c2/0x1d0 [btrfs] btrfs_ioctl_snap_create_v2+0xc4/0x150 [btrfs] btrfs_ioctl+0x8a6/0x2650 [btrfs] ? kmem_cache_free+0x22/0x340 ? do_sys_openat2+0x97/0xe0 __x64_sys_ioctl+0x97/0xd0 do_syscall_64+0x46/0xf0 entry_SYSCALL_64_after_hwframe+0x6e/0x76 RIP: 0033:0x7fe20abe83af RSP: 002b:00007ffe6eff1360 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 0000000000000004 RCX: 00007fe20abe83af RDX: 00007ffe6eff23c0 RSI: 0000000050009417 RDI: 0000000000000003 RBP: 0000000000000003 R08: 0000000000000000 R09: 00007fe20ad16cd0 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007ffe6eff13c0 R14: 00007fe20ad45000 R15: 0000559a120b6d58 </TASK> ---[ end trace 0000000000000000 ]--- BTRFS: error (device vdc: state A) in create_pending_snapshot:1875: errno=-2 No such entry BTRFS info (device vdc: state EA): forced readonly BTRFS warning (device vdc: state EA): Skipping commit of aborted transaction. BTRFS: error (device vdc: state EA) in cleanup_transaction:2055: errno=-2 No such entry This happens because create_pending_snapshot() initializes the new root item as a copy of the source root item. This includes the refs field, which is 0 for a deleted subvolume. The call to btrfs_insert_root() therefore inserts a root with refs == 0. btrfs_get_new_fs_root() then finds the root and returns -ENOENT if refs == 0, which causes create_pending_snapshot() to abort. Fix it by checking the source root's refs before attempting the snapshot, but after locking subvol_sem to avoid racing with deletion. CC: stable@vger.kernel.org # 4.14+ Reviewed-by: Sweet Tea Dorminy <sweettea-kernel@dorminy.me> Reviewed-by: Anand Jain <anand.jain@oracle.com> Signed-off-by: Omar Sandoval <osandov@fb.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
* btrfs: zoned: fix lock ordering in btrfs_zone_activate()Naohiro Aota2024-01-121-6/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The btrfs CI reported a lockdep warning as follows by running generic generic/129. WARNING: possible circular locking dependency detected 6.7.0-rc5+ #1 Not tainted ------------------------------------------------------ kworker/u5:5/793427 is trying to acquire lock: ffff88813256d028 (&cache->lock){+.+.}-{2:2}, at: btrfs_zone_finish_one_bg+0x5e/0x130 but task is already holding lock: ffff88810a23a318 (&fs_info->zone_active_bgs_lock){+.+.}-{2:2}, at: btrfs_zone_finish_one_bg+0x34/0x130 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #1 (&fs_info->zone_active_bgs_lock){+.+.}-{2:2}: ... -> #0 (&cache->lock){+.+.}-{2:2}: ... This is because we take fs_info->zone_active_bgs_lock after a block_group's lock in btrfs_zone_activate() while doing the opposite in other places. Fix the issue by expanding the fs_info->zone_active_bgs_lock's critical section and taking it before a block_group's lock. Fixes: a7e1ac7bdc5a ("btrfs: zoned: reserve zones for an active metadata/system block group") CC: stable@vger.kernel.org # 6.6 Signed-off-by: Naohiro Aota <naohiro.aota@wdc.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
* btrfs: fix unbalanced unlock of mapping_tree_lockNaohiro Aota2024-01-121-2/+0
| | | | | | | | | | The error path of btrfs_get_chunk_map() releases fs_info->mapping_tree_lock. But, it is taken and released in btrfs_find_chunk_map(). So, there is no need to do so. Fixes: 7dc66abb5a47 ("btrfs: use a dedicated data structure for chunk maps") Signed-off-by: Naohiro Aota <naohiro.aota@wdc.com> Signed-off-by: David Sterba <dsterba@suse.com>
* btrfs: ref-verify: free ref cache before clearing mount optFedor Pchelkin2024-01-121-2/+4
| | | | | | | | | | | | | | | | | | | | | | As clearing REF_VERIFY mount option indicates there were some errors in a ref-verify process, a ref cache is not relevant anymore and should be freed. btrfs_free_ref_cache() requires REF_VERIFY option being set so call it just before clearing the mount option. Found by Linux Verification Center (linuxtesting.org) with Syzkaller. Reported-by: syzbot+be14ed7728594dc8bd42@syzkaller.appspotmail.com Fixes: fd708b81d972 ("Btrfs: add a extent ref verify tool") CC: stable@vger.kernel.org # 5.4+ Closes: https://lore.kernel.org/lkml/000000000000e5a65c05ee832054@google.com/ Reported-by: syzbot+c563a3c79927971f950f@syzkaller.appspotmail.com Closes: https://lore.kernel.org/lkml/0000000000007fe09705fdc6086c@google.com/ Reviewed-by: Anand Jain <anand.jain@oracle.com> Signed-off-by: Fedor Pchelkin <pchelkin@ispras.ru> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
* btrfs: fix kvcalloc() arguments order in btrfs_ioctl_send()Dmitry Antipov2024-01-121-2/+2
| | | | | | | | | | | | | | | | | | | When compiling with gcc version 14.0.0 20231220 (experimental) and W=1, I've noticed the following warning: fs/btrfs/send.c: In function 'btrfs_ioctl_send': fs/btrfs/send.c:8208:44: warning: 'kvcalloc' sizes specified with 'sizeof' in the earlier argument and not in the later argument [-Wcalloc-transposed-args] 8208 | sctx->clone_roots = kvcalloc(sizeof(*sctx->clone_roots), | ^ Since 'n' and 'size' arguments of 'kvcalloc()' are multiplied to calculate the final size, their actual order doesn't affect the result and so this is not a bug. But it's still worth to fix it. Signed-off-by: Dmitry Antipov <dmantipov@yandex.ru> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
* btrfs: zoned: optimize hint byte for zoned allocatorNaohiro Aota2024-01-121-0/+18
| | | | | | | | | | | | | | | | | | | | Writing sequentially to a huge file on btrfs on a SMR HDD revealed a decline of the performance (220 MiB/s to 30 MiB/s after 500 minutes). The performance goes down because of increased latency of the extent allocation, which is induced by a traversing of a lot of full block groups. So, this patch optimizes the ffe_ctl->hint_byte by choosing a block group with sufficient size from the active block group list, which does not contain full block groups. After applying the patch, the performance is maintained well. Fixes: 2eda57089ea3 ("btrfs: zoned: implement sequential extent allocation") CC: stable@vger.kernel.org # 5.15+ Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com> Signed-off-by: Naohiro Aota <naohiro.aota@wdc.com> Signed-off-by: David Sterba <dsterba@suse.com>
* btrfs: zoned: factor out prepare_allocation_zoned()Naohiro Aota2024-01-121-13/+19
| | | | | | | | | | Factor out prepare_allocation_zoned() for further extension. While at it, optimize the if-branch a bit. Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com> Signed-off-by: Naohiro Aota <naohiro.aota@wdc.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
* btrfs: pass btrfs_io_geometry into btrfs_max_io_lenJohannes Thumshirn2023-12-151-17/+13
| | | | | | | | | Instead of passing three individual members of 'struct btrfs_io_geometry' into btrfs_max_io_len(), pass a pointer to btrfs_io_geometry. Signed-off-by: Johannes Thumshirn <johannes.thumshirn@wdc.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
* btrfs: pass struct btrfs_io_geometry to set_io_stripeJohannes Thumshirn2023-12-151-17/+15
| | | | | | | | | | Instead of passing three members of 'struct btrfs_io_geometry' into set_io_stripe() pass a pointer to the whole structure and then get the needed members out of btrfs_io_geometry. Signed-off-by: Johannes Thumshirn <johannes.thumshirn@wdc.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
* btrfs: open code set_io_stripe for RAID56Johannes Thumshirn2023-12-151-7/+9
| | | | | | | | | | | | Open code set_io_stripe() for RAID56, as it a) uses a different method to calculate the stripe_index b) doesn't need to go through raid-stripe-tree mapping code. Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Johannes Thumshirn <johannes.thumshirn@wdc.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
* btrfs: change block mapping to switch/case in btrfs_map_blockJohannes Thumshirn2023-12-151-6/+16
| | | | | | | | | | | Now that all the per-profile if/else statement blocks have been converted to calls to helper the conversion to switch/case is straightforward. Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Johannes Thumshirn <johannes.thumshirn@wdc.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
* btrfs: factor out block mapping for single profilesJohannes Thumshirn2023-12-151-3/+9
| | | | | | | | | | Now that we have a container for the I/O geometry that has all the needed information for the block mappings of SINGLE profiles, factor out a helper calculating this information. Signed-off-by: Johannes Thumshirn <johannes.thumshirn@wdc.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
* btrfs: factor out block mapping for RAID5/6Johannes Thumshirn2023-12-151-42/+53
| | | | | | | | | | Now that we have a container for the I/O geometry that has all the needed information for the block mappings of RAID5 and RAID6, factor out a helper calculating this information. Signed-off-by: Johannes Thumshirn <johannes.thumshirn@wdc.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
* btrfs: reduce scope of data_stripes in btrfs_map_blockJohannes Thumshirn2023-12-151-4/+4
| | | | | | | | | | Reduce the scope of 'data_stripes' in btrfs_map_block(). While the change alone may not make too much sense, it helps us factoring out a helper function for the block mapping of RAID56 I/O. Signed-off-by: Johannes Thumshirn <johannes.thumshirn@wdc.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
* btrfs: factor out block mapping for RAID10Johannes Thumshirn2023-12-151-17/+29
| | | | | | | | | | Now that we have a container for the I/O geometry that has all the needed information for the block mappings of RAID10, factor out a helper calculating this information. Signed-off-by: Johannes Thumshirn <johannes.thumshirn@wdc.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
* btrfs: factor out block mapping for DUP profilesJohannes Thumshirn2023-12-151-8/+17
| | | | | | | | | | Now that we have a container for the I/O geometry that has all the needed information for the block mappings of DUP, factor out a helper calculating this information. Signed-off-by: Johannes Thumshirn <johannes.thumshirn@wdc.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
* btrfs: factor out RAID1 block mappingJohannes Thumshirn2023-12-151-10/+21
| | | | | | | | | | Now that we have a container for the I/O geometry that has all the needed information for the block mappings of RAID1, factor out a helper calculating this information. Signed-off-by: Johannes Thumshirn <johannes.thumshirn@wdc.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
* btrfs: factor out block-mapping for RAID0Johannes Thumshirn2023-12-151-4/+10
| | | | | | | | | | Now that we have a container for the I/O geometry that has all the needed information for the block mappings of RAID0, factor out a helper calculating this information. Signed-off-by: Johannes Thumshirn <johannes.thumshirn@wdc.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
* btrfs: re-introduce struct btrfs_io_geometryJohannes Thumshirn2023-12-151-70/+88
| | | | | | | | | | Re-introduce struct btrfs_io_geometry, holding the necessary bits and pieces needed in btrfs_map_block() to decide the I/O geometry of a specific block mapping. Signed-off-by: Johannes Thumshirn <johannes.thumshirn@wdc.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
* btrfs: factor out helper for single device IO checkJohannes Thumshirn2023-12-151-4/+23
| | | | | | | | | | | | | The check in btrfs_map_block() deciding if a particular I/O is targeting a single device is getting more and more convoluted. Factor out the check conditions into a helper function, with no functional change otherwise. Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Johannes Thumshirn <johannes.thumshirn@wdc.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
* btrfs: migrate btrfs_repair_io_failure() to folio interfacesQu Wenruo2023-12-153-12/+20
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | [BUG] Test case btrfs/124 failed if larger metadata folio is enabled, the dying message looks like this: BTRFS error (device dm-2): bad tree block start, mirror 2 want 31686656 have 0 BTRFS info (device dm-2): read error corrected: ino 0 off 31686656 (dev /dev/mapper/test-scratch2 sector 20928) BUG: kernel NULL pointer dereference, address: 0000000000000020 #PF: supervisor read access in kernel mode #PF: error_code(0x0000) - not-present page CPU: 6 PID: 350881 Comm: btrfs Tainted: G OE 6.7.0-rc3-custom+ #128 Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS unknown 2/2/2022 RIP: 0010:btrfs_read_extent_buffer+0x106/0x180 [btrfs] PKRU: 55555554 Call Trace: <TASK> read_tree_block+0x33/0xb0 [btrfs] read_block_for_search+0x23e/0x340 [btrfs] btrfs_search_slot+0x2f9/0xe60 [btrfs] btrfs_lookup_csum+0x75/0x160 [btrfs] btrfs_lookup_bio_sums+0x21a/0x560 [btrfs] btrfs_submit_chunk+0x152/0x680 [btrfs] btrfs_submit_bio+0x1c/0x50 [btrfs] submit_one_bio+0x40/0x80 [btrfs] submit_extent_page+0x158/0x390 [btrfs] btrfs_do_readpage+0x330/0x740 [btrfs] extent_readahead+0x38d/0x6c0 [btrfs] read_pages+0x94/0x2c0 page_cache_ra_unbounded+0x12d/0x190 relocate_file_extent_cluster+0x7c1/0x9d0 [btrfs] relocate_block_group+0x2d3/0x560 [btrfs] btrfs_relocate_block_group+0x2c7/0x4b0 [btrfs] btrfs_relocate_chunk+0x4c/0x1a0 [btrfs] btrfs_balance+0x925/0x13c0 [btrfs] btrfs_ioctl+0x19f1/0x25d0 [btrfs] __x64_sys_ioctl+0x90/0xd0 do_syscall_64+0x3f/0xf0 entry_SYSCALL_64_after_hwframe+0x6e/0x76 [CAUSE] The dying line is at btrfs_repair_io_failure() call inside btrfs_repair_eb_io_failure(). The function is still relying on the extent buffer using page sized folios. When the extent buffer is using larger folio, we go into the 2nd slot of folios[], and triggered the NULL pointer dereference. [FIX] Migrate btrfs_repair_io_failure() to folio interfaces. So that when we hit a larger folio, we just submit the whole folio in one go. This also affects data repair path through btrfs_end_repair_bio(), thankfully data is still fully page based, we can just add an ASSERT(), and use page_folio() to convert the page to folio. Signed-off-by: Qu Wenruo <wqu@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
* btrfs: migrate eb_bitmap_offset() to folio interfacesQu Wenruo2023-12-151-12/+10
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | [BUG] Test case btrfs/002 would fail if larger folios are enabled for metadata: assertion failed: folio, in fs/btrfs/extent_io.c:4358 ------------[ cut here ]------------ kernel BUG at fs/btrfs/extent_io.c:4358! invalid opcode: 0000 [#1] PREEMPT SMP NOPTI CPU: 1 PID: 30916 Comm: fsstress Tainted: G OE 6.7.0-rc3-custom+ #128 Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS unknown 2/2/2022 RIP: 0010:assert_eb_folio_uptodate+0x98/0xe0 [btrfs] Call Trace: <TASK> extent_buffer_test_bit+0x3c/0x70 [btrfs] free_space_test_bit+0xcd/0x140 [btrfs] modify_free_space_bitmap+0x27a/0x430 [btrfs] add_to_free_space_tree+0x8d/0x160 [btrfs] __btrfs_free_extent.isra.0+0xef1/0x13c0 [btrfs] __btrfs_run_delayed_refs+0x786/0x13c0 [btrfs] btrfs_run_delayed_refs+0x33/0x120 [btrfs] btrfs_commit_transaction+0xa2/0x1350 [btrfs] iterate_supers+0x77/0xe0 ksys_sync+0x60/0xa0 __do_sys_sync+0xa/0x20 do_syscall_64+0x3f/0xf0 entry_SYSCALL_64_after_hwframe+0x6e/0x76 </TASK> [CAUSE] The function extent_buffer_test_bit() is not folio compatible. It still assumes the old fixed page size, when an extent buffer with large folio passed in, only eb->folios[0] is populated. Then if the target bit range falls in the 2nd page of the folio, then we would check eb->folios[1], and trigger the ASSERT(). [FIX] Just migrate eb_bitmap_offset() to folio interfaces, using the folio_size() to replace PAGE_SIZE. Signed-off-by: Qu Wenruo <wqu@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
* btrfs: migrate various end io functions to foliosQu Wenruo2023-12-152-77/+81
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | If we still go the old page based iterator functions, like bio_for_each_segment_all(), we can hit middle pages of a folio (compound page). In that case if we set any page flag on those middle pages, we can easily trigger VM_BUG_ON(), as for compound page flags, they should follow their flag policies (normally only set on leading or tail pages). To avoid such problem in the future full folio migration, here we do: - Change from bio_for_each_segment_all() to bio_for_each_folio_all() This completely removes the ability to access the middle page. - Add extra ASSERT()s for data read/write paths To ensure we only get single paged folio for data now. - Rename those end io functions to follow a certain schema * end_bbio_compressed_read() * end_bbio_compressed_write() These two endio functions don't set any page flags, as they use pages not mapped to any address space. They can be very good candidates for higher order folio testing. And they are shared between compression and encoded IO. * end_bbio_data_read() * end_bbio_data_write() * end_bbio_meta_read() * end_bbio_meta_write() The old function names are not unified: - end_bio_extent_writepage() - end_bio_extent_readpage() - extent_buffer_write_end_io() - extent_buffer_read_end_io() They share no schema on where the "end_*io" string should be, nor can be confusing just using "extent_buffer" and "extent" to distinguish data and metadata paths. Signed-off-by: Qu Wenruo <wqu@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
* btrfs: migrate subpage code to folio interfacesQu Wenruo2023-12-1512-284/+281
| | | | | | | | | | | | | | | | | | | | | | | | | | Although subpage itself is conflicting with higher folio, since subpage (sectorsize < PAGE_SIZE and nodesize < PAGE_SIZE) means we will never need higher order folio, there is a hidden pitfall: - btrfs_page_*() helpers Those helpers are an abstraction to handle both subpage and non-subpage cases, which means we're going to pass pages pointers to those helpers. And since those helpers are shared between data and metadata paths, it's unavoidable to let them to handle folios, including higher order folios). Meanwhile for true subpage case, we should only have a single page backed folios anyway, thus add a new ASSERT() for btrfs_subpage_assert() to ensure that. Also since those helpers are shared between both data and metadata, add some extra ASSERT()s for data path to make sure we only get single page backed folio for now. Signed-off-by: Qu Wenruo <wqu@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
* btrfs: migrate get_eb_page_index() and get_eb_offset_in_page() to foliosQu Wenruo2023-12-155-117/+141
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | These two functions are still using the old page based code, which is not going to handle larger folios at all. The migration itself is going to involve the following changes: - PAGE_SIZE -> folio_size() - PAGE_SHIFT -> folio_shift() - get_eb_page_index() -> get_eb_folio_index() - get_eb_offset_in_page() -> get_eb_offset_in_folio() And since we're going to support larger folios, although above straight conversion is good enough, this patch would add extra comments in the involved functions to explain why the same single line code can now cover 3 cases: - folio_size == PAGE_SIZE, sectorsize == PAGE_SIZE, nodesize >= PAGE_SIZE The common, non-subpage case with per-page folio. - folio_size > PAGE_SIZE, sectorsize == PAGE_SIZE, nodesize >= PAGE_SIZE The incoming larger folio, non-subpage case. - folio_size == PAGE_SIZE, sectorsize < PAGE_SIZE, nodesize < PAGE_SIZE The existing subpage case, we won't larger folio anyway. Signed-off-by: Qu Wenruo <wqu@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
generated by cgit v1.2.3 (git 2.25.1) at 2024-11-18 19:44:06 +0000