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2024-07-12Merge tag 'for-6.10-rc7-tag' of ↵Linus Torvalds1-0/+2
git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux Pull btrfs fixes from David Sterba: "Fix a regression in extent map shrinker behaviour. In the past weeks we got reports from users that there are huge latency spikes or freezes. This was bisected to newly added shrinker of extent maps (it was added to fix a build up of the structures in memory). I'm assuming that the freezes would happen to many users after release so I'd like to get it merged now so it's in 6.10. Although the diff size is not small the changes are relatively straightforward, the reporters verified the fixes and we did testing on our side. The fixes: - adjust behaviour under memory pressure and check lock or scheduling conditions, bail out if needed - synchronize tracking of the scanning progress so inode ranges are not skipped or work duplicated - do a delayed iput when scanning a root so evicting an inode does not slow things down in case of lots of dirty data, also fix lockdep warning, a deadlock could happen when writing the dirty data would need to start a transaction" * tag 'for-6.10-rc7-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux: btrfs: avoid races when tracking progress for extent map shrinking btrfs: stop extent map shrinker if reschedule is needed btrfs: use delayed iput during extent map shrinking
2024-07-11btrfs: avoid races when tracking progress for extent map shrinkingFilipe Manana1-0/+2
We store the progress (root and inode numbers) of the extent map shrinker in fs_info without any synchronization but we can have multiple tasks calling into the shrinker during memory allocations when there's enough memory pressure for example. This can result in a task A reading fs_info->extent_map_shrinker_last_ino after another task B updates it, and task A reading fs_info->extent_map_shrinker_last_root before task B updates it, making task A see an odd state that isn't necessarily harmful but may make it skip certain inode ranges or do more work than necessary by going over the same inodes again. These unprotected accesses would also trigger warnings from tools like KCSAN. So add a lock to protect access to these progress fields. Reviewed-by: Josef Bacik <josef@toxicpanda.com> Signed-off-by: Filipe Manana <fdmanana@suse.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2024-06-08Merge tag 'for-6.10-rc2-tag' of ↵Linus Torvalds1-9/+1
git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux Pull btrfs fixes from David Sterba: - fix handling of folio private changes. The private value holds pointer to our extent buffer structure representing a metadata range. Release and create of the range was not properly synchronized when updating the private bit which ended up in double folio_put, leading to all sorts of breakage - fix a crash, reported as duplicate key in metadata, but caused by a race of fsync and size extending write. Requires prealloc target range + fsync and other conditions (log tree state, timing) - fix leak of qgroup extent records after transaction abort * tag 'for-6.10-rc2-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux: btrfs: protect folio::private when attaching extent buffer folios btrfs: fix leak of qgroup extent records after transaction abort btrfs: fix crash on racing fsync and size-extending write into prealloc
2024-06-05btrfs: fix leak of qgroup extent records after transaction abortFilipe Manana1-9/+1
Qgroup extent records are created when delayed ref heads are created and then released after accounting extents at btrfs_qgroup_account_extents(), called during the transaction commit path. If a transaction is aborted we free the qgroup records by calling btrfs_qgroup_destroy_extent_records() at btrfs_destroy_delayed_refs(), unless we don't have delayed references. We are incorrectly assuming that no delayed references means we don't have qgroup extents records. We can currently have no delayed references because we ran them all during a transaction commit and the transaction was aborted after that due to some error in the commit path. So fix this by ensuring we btrfs_qgroup_destroy_extent_records() at btrfs_destroy_delayed_refs() even if we don't have any delayed references. Reported-by: syzbot+0fecc032fa134afd49df@syzkaller.appspotmail.com Link: https://lore.kernel.org/linux-btrfs/0000000000004e7f980619f91835@google.com/ Fixes: 81f7eb00ff5b ("btrfs: destroy qgroup extent records on transaction abort") CC: stable@vger.kernel.org # 6.1+ Reviewed-by: Josef Bacik <josef@toxicpanda.com> Reviewed-by: Qu Wenruo <wqu@suse.com> Signed-off-by: Filipe Manana <fdmanana@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2024-05-21Merge tag 'pull-bd_inode-1' of ↵Linus Torvalds1-3/+3
git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs Pull bdev bd_inode updates from Al Viro: "Replacement of bdev->bd_inode with sane(r) set of primitives by me and Yu Kuai" * tag 'pull-bd_inode-1' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: RIP ->bd_inode dasd_format(): killing the last remaining user of ->bd_inode nilfs_attach_log_writer(): use ->bd_mapping->host instead of ->bd_inode block/bdev.c: use the knowledge of inode/bdev coallocation gfs2: more obvious initializations of mapping->host fs/buffer.c: massage the remaining users of ->bd_inode to ->bd_mapping blk_ioctl_{discard,zeroout}(): we only want ->bd_inode->i_mapping here... grow_dev_folio(): we only want ->bd_inode->i_mapping there use ->bd_mapping instead of ->bd_inode->i_mapping block_device: add a pointer to struct address_space (page cache of bdev) missing helpers: bdev_unhash(), bdev_drop() block: move two helpers into bdev.c block2mtd: prevent direct access of bd_inode dm-vdo: use bdev_nr_bytes(bdev) instead of i_size_read(bdev->bd_inode) blkdev_write_iter(): saner way to get inode and bdev bcachefs: remove dead function bdev_sectors() ext4: remove block_device_ejected() erofs_buf: store address_space instead of inode erofs: switch erofs_bread() to passing offset instead of block number
2024-05-07btrfs: count super block write errors in device instead of tracking folio ↵Matthew Wilcox (Oracle)1-27/+19
error state Currently the error status of super block write is tracked in page/folio status bit Error. For that we need to keep the reference for the whole duration of write and wait. Count the number of superblock writeback errors in the btrfs_device. That means we don't need the folio to stay around until it's waited for, and can avoid the extra call to folio_get/put. Also remove a mention of PageError in a comment as it's the last mention of the page Error state. Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2024-05-07btrfs: use the folio iterator in btrfs_end_super_write()Matthew Wilcox (Oracle)1-13/+6
Iterate over folios instead of bvecs. Switch the order of unlock and put to be the usual order; we know this folio can't be put until it's been waited for, but that's fragile. Remove the calls to ClearPageUptodate / SetPageUptodate -- if PAGE_SIZE is larger than BTRFS_SUPER_INFO_SIZE, we'd be marking the entire folio uptodate without having actually initialised all the bytes in the page. Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2024-05-07btrfs: convert super block writes to folio in write_dev_supers()Matthew Wilcox (Oracle)1-10/+13
This is a direct conversion from pages to folios, assuming single page folio. Also removes some calls to obsolete APIs and some hidden calls to compound_head(). Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2024-05-07btrfs: convert super block writes to folio in wait_dev_supers()Matthew Wilcox (Oracle)1-11/+12
This is a direct conversion from pages to folios, assuming single page folio. Also removes a few calls to compound_head() and calls to obsolete APIs. Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2024-05-07btrfs: use btrfs_is_testing() everywhereDavid Sterba1-2/+2
There are open coded tests of BTRFS_FS_STATE_DUMMY_FS_INFO and we have a wrapper for that that's a compile-time constant when self-tests are not built in. As this is only for development we can save some bytes and conditions on release configs by using the helper in the remaining cases. Reviewed-by: Josef Bacik <josef@toxicpanda.com> Signed-off-by: David Sterba <dsterba@suse.com>
2024-05-07btrfs: initialize delayed inodes xarray without GFP_ATOMICFilipe Manana1-2/+1
There's no need to initialize the delayed inodes xarray with a GFP_ATOMIC flag because that actually does nothing on the xarray operations. That was needed for radix trees, but for xarrays the allocation flags are passed as the last argument to xa_store() (which we are using correctly). So initialize the delayed inodes xarray with a simple xa_init(). Reviewed-by: Josef Bacik <josef@toxicpanda.com> Reviewed-by: Qu Wenruo <wqu@suse.com> Signed-off-by: Filipe Manana <fdmanana@suse.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2024-05-07btrfs: add a global per cpu counter to track number of used extent mapsFilipe Manana1-0/+9
Add a per cpu counter that tracks the total number of extent maps that are in extent trees of inodes that belong to fs trees. This is going to be used in an upcoming change that adds a shrinker for extent maps. Only extent maps for fs trees are considered, because for special trees such as the data relocation tree we don't want to evict their extent maps which are critical for the relocation to work, and since those are limited, it's not a concern to have them in memory during the relocation of a block group. Another case are extent maps for free space cache inodes, which must always remain in memory, but those are limited (there's only one per free space cache inode, which means one per block group). Reviewed-by: Josef Bacik <josef@toxicpanda.com> Signed-off-by: Filipe Manana <fdmanana@suse.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2024-05-07btrfs: change root->root_key.objectid to btrfs_root_id()Josef Bacik1-18/+18
A comment from Filipe on one of my previous cleanups brought my attention to a new helper we have for getting the root id of a root, which makes it easier to read in the code. The changes where made with the following Coccinelle semantic patch: // <smpl> @@ expression E,E1; @@ ( E->root_key.objectid = E1 | - E->root_key.objectid + btrfs_root_id(E) ) // </smpl> Reviewed-by: Filipe Manana <fdmanana@suse.com> Signed-off-by: Josef Bacik <josef@toxicpanda.com> Reviewed-by: David Sterba <dsterba@suse.com> [ minor style fixups ] Signed-off-by: David Sterba <dsterba@suse.com>
2024-05-07btrfs: remove list_empty() check at warn_about_uncommitted_trans()Filipe Manana1-3/+0
At warn_about_uncommitted_trans(), there's no need to check if the list is empty and return, because list_for_each_entry_safe() is safe to call for an empty list, it simply does nothing. So remove the check. Reviewed-by: Qu Wenruo <wqu@suse.com> Signed-off-by: Filipe Manana <fdmanana@suse.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2024-05-07btrfs: free PERTRANS at the end of cleanup_transaction()Boris Burkov1-4/+1
Some of the operations after the free might convert more PERTRANS metadata. Do the freeing as late as possible to eliminate a source of leaked PERTRANS metadata. This helps with the pass rate of generic/269 and generic/475. Reviewed-by: Qu Wenruo <qwu@suse.com> Signed-off-by: Boris Burkov <boris@bur.io> Signed-off-by: David Sterba <dsterba@suse.com>
2024-05-03use ->bd_mapping instead of ->bd_inode->i_mappingAl Viro1-3/+3
Just the low-hanging fruit... Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Link: https://lore.kernel.org/r/20240411145346.2516848-2-viro@zeniv.linux.org.uk Signed-off-by: Christian Brauner <brauner@kernel.org>
2024-03-04btrfs: merge btrfs_del_delalloc_inode() helpersDavid Sterba1-1/+1
The helpers btrfs_del_delalloc_inode() and __btrfs_del_delalloc_inode() don't follow the pattern when the "__" helper does a special case and are in fact reversed regarding the naming. We can merge them into one as there's only one place that needs to be open coded. Reviewed-by: Josef Bacik <josef@toxicpanda.com> Reviewed-by: Qu Wenruo <wqu@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2024-03-04btrfs: stop passing root argument to __btrfs_del_delalloc_inode()Filipe Manana1-1/+1
There's no need to pass a root argument to __btrfs_del_delalloc_inode() and btrfs_del_delalloc_inode(), we can just pass the inode since the root is always the root associated to that inode. Some remove the root argument from these functions. Reviewed-by: Boris Burkov <boris@bur.io> Reviewed-by: Qu Wenruo <wqu@suse.com> Signed-off-by: Filipe Manana <fdmanana@suse.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2024-03-04btrfs: add helper to get fs_info from struct inode pointerDavid Sterba1-3/+3
Add a convenience helper to get a fs_info from a VFS inode pointer instead of open coding the chain or using btrfs_sb() that in some cases does one more pointer hop. This is implemented as a macro (still with type checking) so we don't need full definitions of struct btrfs_inode, btrfs_root or btrfs_fs_info. Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com> Reviewed-by: Anand Jain <anand.jain@oracle.com> Signed-off-by: David Sterba <dsterba@suse.com>
2024-03-04btrfs: add helpers to get fs_info from page/folio pointersDavid Sterba1-1/+1
Add convenience helpers to get a fs_info from a page or folio pointer instead of open coding the chain or using btrfs_sb() that in some cases does one more pointer hop. This is implemented as a macro (still with type checking) so we don't need full definitions of struct page, folio, btrfs_root and btrfs_fs_info. The latter can't be static inlines as this would create loop between ctree.h <-> fs.h, or the headers would have to be restructured. Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com> Reviewed-by: Anand Jain <anand.jain@oracle.com> Signed-off-by: David Sterba <dsterba@suse.com>
2024-03-04btrfs: add helpers to get inode from page/folio pointersDavid Sterba1-1/+2
Add convenience helpers to get a struct btrfs_inode from a page or folio pointer instead of open coding the chain or intermediate BTRFS_I. This is implemented as a macro (still with type checking) so we don't need full definitions of struct page or address_space. Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com> Reviewed-by: Anand Jain <anand.jain@oracle.com> Signed-off-by: David Sterba <dsterba@suse.com>
2024-03-04btrfs: change BUG_ON to assertion in btrfs_read_roots()David Sterba1-1/+1
There's one caller of btrfs_read_roots() and that already uses the tree_root pointer, it's pointless to BUG_ON on it. As it's an assumption of the initialization helpers make it an assert instead. Reviewed-by: Josef Bacik <josef@toxicpanda.com> Reviewed-by: Anand Jain <anand.jain@oracle.com> Signed-off-by: David Sterba <dsterba@suse.com>
2024-03-04btrfs: handle invalid root reference found in btrfs_init_root_free_objectid()David Sterba1-1/+8
The btrfs_init_root_free_objectid() looks up a root by a key, allowing to do an inexact search when key->offset is -1. It's never expected to find such item, as it would break the allowed range of a root id. Reviewed-by: Josef Bacik <josef@toxicpanda.com> Reviewed-by: Anand Jain <anand.jain@oracle.com> Signed-off-by: David Sterba <dsterba@suse.com>
2024-03-04btrfs: remove unused included headersDavid Sterba1-1/+0
With help of neovim, LSP and clangd we can identify header files that are not actually needed to be included in the .c files. This is focused only on removal (with minor fixups), further cleanups are possible but will require doing the header files properly with forward declarations, minimized includes and include-what-you-use care. Reviewed-by: Josef Bacik <josef@toxicpanda.com> Signed-off-by: David Sterba <dsterba@suse.com>
2024-03-04btrfs: replace sb::s_blocksize by fs_info::sectorsizeDavid Sterba1-0/+2
The block size stored in the super block is used by subsystems outside of btrfs and it's a copy of fs_info::sectorsize. Unify that to always use our sectorsize, with the exception of mount where we first need to use fixed values (4K) until we read the super block and can set the sectorsize. Replace all uses, in most cases it's fewer pointer indirections. Reviewed-by: Josef Bacik <josef@toxicpanda.com> Reviewed-by: Anand Jain <anand.jain@oracle.com> Signed-off-by: David Sterba <dsterba@suse.com>
2024-03-04btrfs: WARN_ON_ONCE() in our leak detection codeJosef Bacik1-0/+1
fstests looks for WARN_ON's in dmesg. Add WARN_ON_ONCE() to our leak detection code (enabled only in debug builds) so that fstests will fail if these things trip at all. This will allow us to easily catch problems with our reference counting that may otherwise go unnoticed. Reviewed-by: Neal Gompa <neal@gompa.dev> 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>
2024-03-04btrfs: cache folio size and shift in extent_bufferQu Wenruo1-1/+1
After the conversion to folio interfaces (but without the patch to enable larger folio allocation), there is an LTP report about observable performance drop on metadata heavy operations. https://lore.kernel.org/linux-btrfs/202312221750.571925bd-oliver.sang@intel.com/ This drop is caused by the extra code of calculating the folio_size()/folio_shift(), instead of the old hard coded PAGE_SIZE/PAGE_SHIFT. To slightly reduce the overhead, just cache both folio_size and folio_shift in extent_buffer. The two new members (u32 folio_size and u8 folio_shift) are stored inside the holes of extent_buffer. folio_size is shared with len, which is reduced to u32. The size of eb does not change. Signed-off-by: Qu Wenruo <wqu@suse.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2024-03-01btrfs: fix double free of anonymous device after snapshot creation failureFilipe Manana1-11/+11
When creating a snapshot we may do a double free of an anonymous device in case there's an error committing the transaction. The second free may result in freeing an anonymous device number that was allocated by some other subsystem in the kernel or another btrfs filesystem. The steps that lead to this: 1) At ioctl.c:create_snapshot() we allocate an anonymous device number and assign it to pending_snapshot->anon_dev; 2) Then we call btrfs_commit_transaction() and end up at transaction.c:create_pending_snapshot(); 3) There we call btrfs_get_new_fs_root() and pass it the anonymous device number stored in pending_snapshot->anon_dev; 4) btrfs_get_new_fs_root() frees that anonymous device number because btrfs_lookup_fs_root() returned a root - someone else did a lookup of the new root already, which could some task doing backref walking; 5) After that some error happens in the transaction commit path, and at ioctl.c:create_snapshot() we jump to the 'fail' label, and after that we free again the same anonymous device number, which in the meanwhile may have been reallocated somewhere else, because pending_snapshot->anon_dev still has the same value as in step 1. Recently syzbot ran into this and reported the following trace: ------------[ cut here ]------------ ida_free called for id=51 which is not allocated. WARNING: CPU: 1 PID: 31038 at lib/idr.c:525 ida_free+0x370/0x420 lib/idr.c:525 Modules linked in: CPU: 1 PID: 31038 Comm: syz-executor.2 Not tainted 6.8.0-rc4-syzkaller-00410-gc02197fc9076 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/25/2024 RIP: 0010:ida_free+0x370/0x420 lib/idr.c:525 Code: 10 42 80 3c 28 (...) RSP: 0018:ffffc90015a67300 EFLAGS: 00010246 RAX: be5130472f5dd000 RBX: 0000000000000033 RCX: 0000000000040000 RDX: ffffc90009a7a000 RSI: 000000000003ffff RDI: 0000000000040000 RBP: ffffc90015a673f0 R08: ffffffff81577992 R09: 1ffff92002b4cdb4 R10: dffffc0000000000 R11: fffff52002b4cdb5 R12: 0000000000000246 R13: dffffc0000000000 R14: ffffffff8e256b80 R15: 0000000000000246 FS: 00007fca3f4b46c0(0000) GS:ffff8880b9500000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f167a17b978 CR3: 000000001ed26000 CR4: 0000000000350ef0 Call Trace: <TASK> btrfs_get_root_ref+0xa48/0xaf0 fs/btrfs/disk-io.c:1346 create_pending_snapshot+0xff2/0x2bc0 fs/btrfs/transaction.c:1837 create_pending_snapshots+0x195/0x1d0 fs/btrfs/transaction.c:1931 btrfs_commit_transaction+0xf1c/0x3740 fs/btrfs/transaction.c:2404 create_snapshot+0x507/0x880 fs/btrfs/ioctl.c:848 btrfs_mksubvol+0x5d0/0x750 fs/btrfs/ioctl.c:998 btrfs_mksnapshot+0xb5/0xf0 fs/btrfs/ioctl.c:1044 __btrfs_ioctl_snap_create+0x387/0x4b0 fs/btrfs/ioctl.c:1306 btrfs_ioctl_snap_create_v2+0x1ca/0x400 fs/btrfs/ioctl.c:1393 btrfs_ioctl+0xa74/0xd40 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:871 [inline] __se_sys_ioctl+0xfe/0x170 fs/ioctl.c:857 do_syscall_64+0xfb/0x240 entry_SYSCALL_64_after_hwframe+0x6f/0x77 RIP: 0033:0x7fca3e67dda9 Code: 28 00 00 00 (...) RSP: 002b:00007fca3f4b40c8 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 00007fca3e7abf80 RCX: 00007fca3e67dda9 RDX: 00000000200005c0 RSI: 0000000050009417 RDI: 0000000000000003 RBP: 00007fca3e6ca47a R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 000000000000000b R14: 00007fca3e7abf80 R15: 00007fff6bf95658 </TASK> Where we get an explicit message where we attempt to free an anonymous device number that is not currently allocated. It happens in a different code path from the example below, at btrfs_get_root_ref(), so this change may not fix the case triggered by syzbot. To fix at least the code path from the example above, change btrfs_get_root_ref() and its callers to receive a dev_t pointer argument for the anonymous device number, so that in case it frees the number, it also resets it to 0, so that up in the call chain we don't attempt to do the double free. CC: stable@vger.kernel.org # 5.10+ Link: https://lore.kernel.org/linux-btrfs/000000000000f673a1061202f630@google.com/ Fixes: e03ee2fe873e ("btrfs: do not ASSERT() if the newly created subvolume already got read") Signed-off-by: Filipe Manana <fdmanana@suse.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2024-01-31btrfs: do not ASSERT() if the newly created subvolume already got readQu Wenruo1-2/+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>
2023-12-16btrfs: migrate btrfs_repair_io_failure() to folio interfacesQu Wenruo1-6/+7
[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>
2023-12-16btrfs: migrate subpage code to folio interfacesQu Wenruo1-2/+2
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>
2023-12-16btrfs: migrate get_eb_page_index() and get_eb_offset_in_page() to foliosQu Wenruo1-1/+1
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>
2023-12-16btrfs: cleanup metadata page pointer usageQu Wenruo1-0/+6
Although we have migrated extent_buffer::pages[] to folios[], we're still mostly using the folio_page() help to grab the page. This patch would do the following cleanups for metadata: - Introduce num_extent_folios() helper This is to replace most num_extent_pages() callers. - Use num_extent_folios() to iterate future large folios This allows us to use things like bio_add_folio()/bio_add_folio_nofail(), and only set the needed flags for the folio (aka the leading/tailing page), which reduces the loop iteration to 1 for large folios. - Change metadata related functions to use folio pointers Including their function name, involving: * attach_extent_buffer_page() * detach_extent_buffer_page() * page_range_has_eb() * btrfs_release_extent_buffer_pages() * btree_clear_page_dirty() * btrfs_page_inc_eb_refs() * btrfs_page_dec_eb_refs() - Change btrfs_is_subpage() to accept an address_space pointer This is to allow both page->mapping and folio->mapping to be utilized. As data is still using the old per-page code, and may keep so for a while. - Special corner case place holder for future order mismatches between extent buffer and inode filemap For now it's just a block of comments and a dead ASSERT(), no real handling yet. The subpage code would still go page, just because subpage and large folio are conflicting conditions, thus we don't need to bother subpage with higher order folios at all. Just folio_page(folio, 0) would be enough. Signed-off-by: Qu Wenruo <wqu@suse.com> Reviewed-by: David Sterba <dsterba@suse.com> [ minor styling tweaks ] Signed-off-by: David Sterba <dsterba@suse.com>
2023-12-16btrfs: migrate extent_buffer::pages[] to folioQu Wenruo1-9/+10
For now extent_buffer::pages[] are still only accepting single page pointer, thus we can migrate to folios pretty easily. As for single page, page and folio are 1:1 mapped, including their page flags. This patch would just do the conversion from struct page to struct folio, providing the first step to higher order folio in the future. This conversion is pretty simple: - extent_buffer::pages[] -> extent_buffer::folios[] - page_address(eb->pages[i]) -> folio_address(eb->pages[i]) - eb->pages[i] -> folio_page(eb->folios[i], 0) There would be more specific cleanups preparing for the incoming higher order folio support. Signed-off-by: Qu Wenruo <wqu@suse.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2023-12-16btrfs: switch btrfs_root::delayed_nodes_tree to xarray from radix-treeDavid Sterba1-1/+2
The radix-tree has been superseded by the xarray (https://lwn.net/Articles/745073), this patch converts the btrfs_root::delayed_nodes, the APIs are used in a simple way. First idea is to do xa_insert() but this would require GFP_ATOMIC allocation which we want to avoid if possible. The preload mechanism of radix-tree can be emulated within the xarray API. - xa_reserve() with GFP_NOFS outside of the lock, the reserved entry is inserted atomically at most once - xa_store() under a lock, in case something races in we can detect that and xa_load() returns a valid pointer All uses of xa_load() must check for a valid pointer in case they manage to get between the xa_reserve() and xa_store(), this is handled in btrfs_get_delayed_node(). Otherwise the functionality is equivalent, xarray implements the radix-tree and there should be no performance difference. The patch continues the efforts started in 253bf57555e451 ("btrfs: turn delayed_nodes_tree into an XArray") and fixes the problems with locking and GFP flags 088aea3b97e0ae ("Revert "btrfs: turn delayed_nodes_tree into an XArray""). Reviewed-by: Filipe Manana <fdmanana@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2023-12-15btrfs: set clear_cache if we use usebackuprootJosef Bacik1-3/+0
We're currently setting this when we try to load the roots and we see that usebackuproot is set. Instead set this at mount option parsing time. Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com> Reviewed-by: Anand Jain <anand.jain@oracle.com> Acked-by: Christian Brauner <brauner@kernel.org> Signed-off-by: Josef Bacik <josef@toxicpanda.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2023-12-15btrfs: move one shot mount option clearing to super.cJosef Bacik1-15/+1
There's no reason this has to happen in open_ctree, and in fact in the old mount API we had to call this from remount. Move this to super.c, unexport it, and call it from both mount and reconfigure. Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com> Reviewed-by: Anand Jain <anand.jain@oracle.com> Acked-by: Christian Brauner <brauner@kernel.org> Signed-off-by: Josef Bacik <josef@toxicpanda.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2023-12-15btrfs: move the device specific mount options to super.cJosef Bacik1-23/+0
We add these mount options based on the fs_devices settings, which can be set once we've opened the fs_devices. Move these into their own helper and call it from get_tree_super. Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com> Reviewed-by: Anand Jain <anand.jain@oracle.com> Acked-by: Christian Brauner <brauner@kernel.org> Signed-off-by: Josef Bacik <josef@toxicpanda.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2023-12-15btrfs: switch to the new mount APIJosef Bacik1-2/+9
Now that we have all of the parts in place to use the new mount API, switch our fs_type to use the new callbacks. There are a few things that have to be done at the same time because of the order of operations changes that come along with the new mount API. These must be done in the same patch otherwise things will go wrong. 1. Export and use btrfs_check_options in open_ctree(). This is because the options are done ahead of time, and we need to check them once we have the feature flags loaded. 2. Update the free space cache settings. Since we're coming in with the options already set we need to make sure we don't undo what the user has asked for. 3. Set our sb_flags at init_fs_context time, the fs_context stuff is trying to manage the sb_flagss itself, so move that into init_fs_context and out of the fill super part. Additionally I've marked the unused functions with __maybe_unused and will remove them in a future patch. Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com> Acked-by: Christian Brauner <brauner@kernel.org> Signed-off-by: Josef Bacik <josef@toxicpanda.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2023-12-15btrfs: add a NOSPACECACHE mount option flagJosef Bacik1-0/+1
With the old mount API we'd pre-populate the mount options with the space cache settings of the file system, and then the user toggled them on or off with the mount options. When we switch to the new mount API the mount options will be set before we get into opening the file system, so we need a flag to indicate that the user explicitly asked for -o nospace_cache so we can make the appropriate changes after the fact. Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com> Reviewed-by: Anand Jain <anand.jain@oracle.com> Acked-by: Christian Brauner <brauner@kernel.org> Signed-off-by: Josef Bacik <josef@toxicpanda.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2023-12-15btrfs: do not allow free space tree rebuild on extent tree v2Josef Bacik1-1/+5
We currently don't allow these options to be set if we're extent tree v2 via the mount option parsing. However when we switch to the new mount API we'll no longer have the super block loaded, so won't be able to make this distinction at mount option parsing time. Address this by checking for extent tree v2 at the point where we make the decision to rebuild the free space tree. Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com> Reviewed-by: Anand Jain <anand.jain@oracle.com> Acked-by: Christian Brauner <brauner@kernel.org> Signed-off-by: Josef Bacik <josef@toxicpanda.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2023-12-15btrfs: move space cache settings into open_ctreeJosef Bacik1-11/+6
Currently we pre-load the space cache settings in btrfs_parse_options, however when we switch to the new mount API the mount option parsing will happen before we have the super block loaded. Add a helper to set the appropriate options based on the fs settings, this will allow us to have consistent free space cache settings. This also folds in the space cache related decisions we make for subpage sectorsize support, so all of this is done in one place. Since this was being called by parse options it looks like we're changing the behavior of remount, but in fact we aren't. The pre-loading of the free space cache settings is done because we want to handle the case of users not using any space_cache options, we'll derive the appropriate mount option based on the on disk state. On remount this wouldn't reset anything as we'll have cleared the v1 cache generation if we mounted -o nospace_cache. Similarly it's impossible to turn off the free space tree without specifically saying -o nospace_cache,clear_cache, which will delete the free space tree and clear the compat_ro option. Again in this case calling this code in remount wouldn't result in any change. Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com> Reviewed-by: Anand Jain <anand.jain@oracle.com> Acked-by: Christian Brauner <brauner@kernel.org> Signed-off-by: Josef Bacik <josef@toxicpanda.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2023-12-15btrfs: set default compress type at btrfs_init_fs_info timeJosef Bacik1-7/+3
With the new mount API we'll be setting our compression well before we call open_ctree. We don't want to overwrite our settings, so set the default in btrfs_init_fs_info instead of open_ctree. Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com> Reviewed-by: Anand Jain <anand.jain@oracle.com> Acked-by: Christian Brauner <brauner@kernel.org> Signed-off-by: Josef Bacik <josef@toxicpanda.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2023-12-15btrfs: allow extent buffer helpers to skip cross-page handlingQu Wenruo1-3/+14
Currently btrfs extent buffer helpers are doing all the cross-page handling, as there is no guarantee that all those eb pages are contiguous. However on systems with enough memory, there is a very high chance the page cache for btree_inode are allocated with physically contiguous pages. In that case, we can skip all the complex cross-page handling, thus speeding up the code. This patch adds a new member, extent_buffer::addr, which is only set to non-NULL if all the extent buffer pages are physically contiguous. Signed-off-by: Qu Wenruo <wqu@suse.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2023-12-15btrfs: zoned: don't clear dirty flag of extent bufferJohannes Thumshirn1-1/+6
One a zoned filesystem, never clear the dirty flag of an extent buffer, but instead mark it as zeroout. On writeout, when encountering a marked extent_buffer, zero it out. Reviewed-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Josef Bacik <josef@toxicpanda.com> Signed-off-by: Johannes Thumshirn <johannes.thumshirn@wdc.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2023-12-15btrfs: rename EXTENT_BUFFER_NO_CHECK to EXTENT_BUFFER_ZONED_ZEROOUTJohannes Thumshirn1-1/+1
EXTENT_BUFFER_ZONED_ZEROOUT better describes the state of the extent buffer, namely it is written as all zeros. This is needed in zoned mode, to preserve I/O ordering. Reviewed-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Josef Bacik <josef@toxicpanda.com> Signed-off-by: Johannes Thumshirn <johannes.thumshirn@wdc.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2023-12-15btrfs: use a dedicated data structure for chunk mapsFilipe Manana1-3/+4
Currently we abuse the extent_map structure for two purposes: 1) To actually represent extents for inodes; 2) To represent chunk mappings. This is odd and has several disadvantages: 1) To create a chunk map, we need to do two memory allocations: one for an extent_map structure and another one for a map_lookup structure, so more potential for an allocation failure and more complicated code to manage and link two structures; 2) For a chunk map we actually only use 3 fields (24 bytes) of the respective extent map structure: the 'start' field to have the logical start address of the chunk, the 'len' field to have the chunk's size, and the 'orig_block_len' field to contain the chunk's stripe size. Besides wasting a memory, it's also odd and not intuitive at all to have the stripe size in a field named 'orig_block_len'. We are also using 'block_len' of the extent_map structure to contain the chunk size, so we have 2 fields for the same value, 'len' and 'block_len', which is pointless; 3) When an extent map is associated to a chunk mapping, we set the bit EXTENT_FLAG_FS_MAPPING on its flags and then make its member named 'map_lookup' point to the associated map_lookup structure. This means that for an extent map associated to an inode extent, we are not using this 'map_lookup' pointer, so wasting 8 bytes (on a 64 bits platform); 4) Extent maps associated to a chunk mapping are never merged or split so it's pointless to use the existing extent map infrastructure. So add a dedicated data structure named 'btrfs_chunk_map' to represent chunk mappings, this is basically the existing map_lookup structure with some extra fields: 1) 'start' to contain the chunk logical address; 2) 'chunk_len' to contain the chunk's length; 3) 'stripe_size' for the stripe size; 4) 'rb_node' for insertion into a rb tree; 5) 'refs' for reference counting. This way we do a single memory allocation for chunk mappings and we don't waste memory for them with unused/unnecessary fields from an extent_map. We also save 8 bytes from the extent_map structure by removing the 'map_lookup' pointer, so the size of struct extent_map is reduced from 144 bytes down to 136 bytes, and we can now have 30 extents map per 4K page instead of 28. Reviewed-by: Josef Bacik <josef@toxicpanda.com> Signed-off-by: Filipe Manana <fdmanana@suse.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2023-12-15btrfs: remove log_extents_lock and logged_list from struct btrfs_rootFilipe Manana1-4/+0
The logged_list[2] and log_extents_lock[2] members of struct btrfs_root are no longer used, their last use was removed in commit 5636cf7d6dc8 ("btrfs: remove the logged extents infrastructure"). So remove these fields. This reduces the size of struct btrfs_root, on a release kernel, from 1392 bytes down to 1352 bytes. Signed-off-by: Filipe Manana <fdmanana@suse.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2023-12-07btrfs: free qgroup pertrans reserve on transaction abortBoris Burkov1-0/+28
If we abort a transaction, we never run the code that frees the pertrans qgroup reservation. This results in warnings on unmount as that reservation has been leaked. The leak isn't a huge issue since the fs is read-only, but it's better to clean it up when we know we can/should. Do it during the cleanup_transaction step of aborting. CC: stable@vger.kernel.org # 5.15+ Reviewed-by: Qu Wenruo <wqu@suse.com> Signed-off-by: Boris Burkov <boris@bur.io> Signed-off-by: David Sterba <dsterba@suse.com>
2023-11-24btrfs: add dmesg output for first mount and last unmount of a filesystemQu Wenruo1-0/+1
There is a feature request to add dmesg output when unmounting a btrfs. There are several alternative methods to do the same thing, but with their own problems: - Use eBPF to watch btrfs_put_super()/open_ctree() Not end user friendly, they have to dip their head into the source code. - Watch for directory /sys/fs/<uuid>/ This is way more simple, but still requires some simple device -> uuid lookups. And a script needs to use inotify to watch /sys/fs/. Compared to all these, directly outputting the information into dmesg would be the most simple one, with both device and UUID included. And since we're here, also add the output when mounting a filesystem for the first time for parity. A more fine grained monitoring of subvolume mounts should be done by another layer, like audit. Now mounting a btrfs with all default mkfs options would look like this: [81.906566] BTRFS info (device dm-8): first mount of filesystem 633b5c16-afe3-4b79-b195-138fe145e4f2 [81.907494] BTRFS info (device dm-8): using crc32c (crc32c-intel) checksum algorithm [81.908258] BTRFS info (device dm-8): using free space tree [81.912644] BTRFS info (device dm-8): auto enabling async discard [81.913277] BTRFS info (device dm-8): checking UUID tree [91.668256] BTRFS info (device dm-8): last unmount of filesystem 633b5c16-afe3-4b79-b195-138fe145e4f2 CC: stable@vger.kernel.org # 5.4+ Link: https://github.com/kdave/btrfs-progs/issues/689 Reviewed-by: Anand Jain <anand.jain@oracle.com> Signed-off-by: Qu Wenruo <wqu@suse.com> Reviewed-by: David Sterba <dsterba@suse.com> [ update changelog ] Signed-off-by: David Sterba <dsterba@suse.com>