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2024-02-09docs: filesystems: fix typo in docsVincenzo Mezzela
This patch resolves a spelling error in the filesystem documentation. It is submitted as part of my application to the "Linux Kernel Bug Fixing Spring Unpaid 2024" mentorship program of the Linux Kernel Foundation. Signed-off-by: Vincenzo Mezzela <vincenzo.mezzela@gmail.com> Link: https://lore.kernel.org/r/20240208162032.109184-1-vincenzo.mezzela@gmail.com Signed-off-by: Christian Brauner <brauner@kernel.org>
2024-02-06fs: remove the inode argument to ->d_real() methodAmir Goldstein
The only remaining user of ->d_real() method is d_real_inode(), which passed NULL inode argument to get the real data dentry. There are no longer any users that call ->d_real() with a non-NULL inode argument for getting a detry from a specific underlying layer. Remove the inode argument of the method and replace it with an integer 'type' argument, to allow callers to request the real metadata dentry instead of the real data dentry. All the current users of d_real_inode() (e.g. uprobe) continue to get the real data inode. Caller that need to get the real metadata inode (e.g. IMA/EVM) can use d_inode(d_real(dentry, D_REAL_METADATA)). Signed-off-by: Amir Goldstein <amir73il@gmail.com> Link: https://lore.kernel.org/r/20240202110132.1584111-3-amir73il@gmail.com Tested-by: Stefan Berger <stefanb@linux.ibm.com> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Christian Brauner <brauner@kernel.org>
2024-02-05f2fs: introduce FAULT_BLKADDR_CONSISTENCEChao Yu
We will encounter below inconsistent status when FAULT_BLKADDR type fault injection is on. Info: checkpoint state = d6 : nat_bits crc fsck compacted_summary orphan_inodes sudden-power-off [ASSERT] (fsck_chk_inode_blk:1254) --> ino: 0x1c100 has i_blocks: 000000c0, but has 191 blocks [FIX] (fsck_chk_inode_blk:1260) --> [0x1c100] i_blocks=0x000000c0 -> 0xbf [FIX] (fsck_chk_inode_blk:1269) --> [0x1c100] i_compr_blocks=0x00000026 -> 0x27 [ASSERT] (fsck_chk_inode_blk:1254) --> ino: 0x1cadb has i_blocks: 0000002f, but has 46 blocks [FIX] (fsck_chk_inode_blk:1260) --> [0x1cadb] i_blocks=0x0000002f -> 0x2e [FIX] (fsck_chk_inode_blk:1269) --> [0x1cadb] i_compr_blocks=0x00000011 -> 0x12 [ASSERT] (fsck_chk_inode_blk:1254) --> ino: 0x1c62c has i_blocks: 00000002, but has 1 blocks [FIX] (fsck_chk_inode_blk:1260) --> [0x1c62c] i_blocks=0x00000002 -> 0x1 After we inject fault into f2fs_is_valid_blkaddr() during truncation, a) it missed to increase @nr_free or @valid_blocks b) it can cause in blkaddr leak in truncated dnode Which may cause inconsistent status. This patch separates FAULT_BLKADDR_CONSISTENCE from FAULT_BLKADDR, and rename FAULT_BLKADDR to FAULT_BLKADDR_VALIDITY so that we can: a) use FAULT_BLKADDR_CONSISTENCE in f2fs_truncate_data_blocks_range() to simulate inconsistent issue independently, then it can verify fsck repair flow. b) FAULT_BLKADDR_VALIDITY fault will not cause any inconsistent status, we can just use it to check error path handling in kernel side. Reviewed-by: Daeho Jeong <daehojeong@google.com> Signed-off-by: Chao Yu <chao@kernel.org> Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2024-01-24fs: remove NTFS classic from docum. indexRandy Dunlap
With the remove of the NTFS classic filesystem, also remove its documentation entry from the filesystems index to prevent a kernel-doc warning: Documentation/filesystems/index.rst:63: WARNING: toctree contains reference to nonexisting document 'filesystems/ntfs' Fixes: 9c67092ed339 ("fs: Remove NTFS classic") Signed-off-by: Randy Dunlap <rdunlap@infradead.org> Link: https://lore.kernel.org/r/20240124011424.731-1-rdunlap@infradead.org Cc: Matthew Wilcox (Oracle) <willy@infradead.org> Cc: Alexander Viro <viro@zeniv.linux.org.uk> Cc: Christian Brauner <brauner@kernel.org> Cc: Jan Kara <jack@suse.cz> Cc: <linux-fsdevel@vger.kernel.org> Cc: Namjae Jeon <linkinjeon@kernel.org> Cc: Dave Chinner <david@fromorbit.com> Cc: Anton Altaparmakov <anton@tuxera.com> Cc: Jonathan Corbet <corbet@lwn.net> Cc: <linux-doc@vger.kernel.org> Signed-off-by: Christian Brauner <brauner@kernel.org>
2024-01-24fs: Remove NTFS classicMatthew Wilcox (Oracle)
The replacement, NTFS3, was merged over two years ago. It is now time to remove the original from the tree as it is the last user of several APIs, and it is not worth changing. Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org> Link: https://lore.kernel.org/r/20240115072025.2071931-1-willy@infradead.org Acked-by: Namjae Jeon <linkinjeon@kernel.org> Acked-by: Dave Chinner <david@fromorbit.com> Cc: Anton Altaparmakov <anton@tuxera.com> Cc: Namjae Jeon <linkinjeon@kernel.org> Signed-off-by: Christian Brauner <brauner@kernel.org>
2024-01-23ovl: mark xwhiteouts directory with overlay.opaque='x'Amir Goldstein
An opaque directory cannot have xwhiteouts, so instead of marking an xwhiteouts directory with a new xattr, overload overlay.opaque xattr for marking both opaque dir ('y') and xwhiteouts dir ('x'). This is more efficient as the overlay.opaque xattr is checked during lookup of directory anyway. This also prevents unnecessary checking the xattr when reading a directory without xwhiteouts, i.e. most of the time. Note that the xwhiteouts marker is not checked on the upper layer and on the last layer in lowerstack, where xwhiteouts are not expected. Fixes: bc8df7a3dc03 ("ovl: Add an alternative type of whiteout") Cc: <stable@vger.kernel.org> # v6.7 Reviewed-by: Alexander Larsson <alexl@redhat.com> Tested-by: Alexander Larsson <alexl@redhat.com> Signed-off-by: Amir Goldstein <amir73il@gmail.com>
2024-01-19Merge tag '6.8-rc-smb-server-fixes-part2' of git://git.samba.org/ksmbdLinus Torvalds
Pull more smb server updates from Steve French: - Fix for incorrect oplock break on directories when leases disabled - UAF fix for race between create and destroy of tcp connection - Important session setup SPNEGO fix - Update ksmbd feature status summary * tag '6.8-rc-smb-server-fixes-part2' of git://git.samba.org/ksmbd: ksmbd: only v2 leases handle the directory ksmbd: fix UAF issue in ksmbd_tcp_new_connection() ksmbd: validate mech token in session setup ksmbd: update feature status in documentation
2024-01-19Merge tag 'vfs-6.8.netfs' of ↵Linus Torvalds
gitolite.kernel.org:pub/scm/linux/kernel/git/vfs/vfs Pull netfs updates from Christian Brauner: "This extends the netfs helper library that network filesystems can use to replace their own implementations. Both afs and 9p are ported. cifs is ready as well but the patches are way bigger and will be routed separately once this is merged. That will remove lots of code as well. The overal goal is to get high-level I/O and knowledge of the page cache and ouf of the filesystem drivers. This includes knowledge about the existence of pages and folios The pull request converts afs and 9p. This removes about 800 lines of code from afs and 300 from 9p. For 9p it is now possible to do writes in larger than a page chunks. Additionally, multipage folio support can be turned on for 9p. Separate patches exist for cifs removing another 2000+ lines. I've included detailed information in the individual pulls I took. Summary: - Add NFS-style (and Ceph-style) locking around DIO vs buffered I/O calls to prevent these from happening at the same time. - Support for direct and unbuffered I/O. - Support for write-through caching in the page cache. - O_*SYNC and RWF_*SYNC writes use write-through rather than writing to the page cache and then flushing afterwards. - Support for write-streaming. - Support for write grouping. - Skip reads for which the server could only return zeros or EOF. - The fscache module is now part of the netfs library and the corresponding maintainer entry is updated. - Some helpers from the fscache subsystem are renamed to mark them as belonging to the netfs library. - Follow-up fixes for the netfs library. - Follow-up fixes for the 9p conversion" * tag 'vfs-6.8.netfs' of gitolite.kernel.org:pub/scm/linux/kernel/git/vfs/vfs: (50 commits) netfs: Fix wrong #ifdef hiding wait cachefiles: Fix signed/unsigned mixup netfs: Fix the loop that unmarks folios after writing to the cache netfs: Fix interaction between write-streaming and cachefiles culling netfs: Count DIO writes netfs: Mark netfs_unbuffered_write_iter_locked() static netfs: Fix proc/fs/fscache symlink to point to "netfs" not "../netfs" netfs: Rearrange netfs_io_subrequest to put request pointer first 9p: Use length of data written to the server in preference to error 9p: Do a couple of cleanups 9p: Fix initialisation of netfs_inode for 9p cachefiles: Fix __cachefiles_prepare_write() 9p: Use netfslib read/write_iter afs: Use the netfs write helpers netfs: Export the netfs_sreq tracepoint netfs: Optimise away reads above the point at which there can be no data netfs: Implement a write-through caching option netfs: Provide a launder_folio implementation netfs: Provide a writepages implementation netfs, cachefiles: Pass upper bound length to allow expansion ...
2024-01-14ksmbd: update feature status in documentationNamjae Jeon
Update ksmbd feature status in documentation file. - add support for v2 lease feature and SMB3 CCM/GCM256 encryption. - add planned compression, quic, gmac signing features. Signed-off-by: Namjae Jeon <linkinjeon@kernel.org> Signed-off-by: Steve French <stfrench@microsoft.com>
2024-01-11Merge tag 'pull-dcache' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs Pull dcache updates from Al Viro: "Change of locking rules for __dentry_kill(), regularized refcounting rules in that area, assorted cleanups and removal of weird corner cases (e.g. now ->d_iput() on child is always called before the parent might hit __dentry_kill(), etc)" * tag 'pull-dcache' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (40 commits) dcache: remove unnecessary NULL check in dget_dlock() kill DCACHE_MAY_FREE __d_unalias() doesn't use inode argument d_alloc_parallel(): in-lookup hash insertion doesn't need an RCU variant get rid of DCACHE_GENOCIDE d_genocide(): move the extern into fs/internal.h simple_fill_super(): don't bother with d_genocide() on failure nsfs: use d_make_root() d_alloc_pseudo(): move setting ->d_op there from the (sole) caller kill d_instantate_anon(), fold __d_instantiate_anon() into remaining caller retain_dentry(): introduce a trimmed-down lockless variant __dentry_kill(): new locking scheme d_prune_aliases(): use a shrink list switch select_collect{,2}() to use of to_shrink_list() to_shrink_list(): call only if refcount is 0 fold dentry_kill() into dput() don't try to cut corners in shrink_lock_dentry() fold the call of retain_dentry() into fast_dput() Call retain_dentry() with refcount 0 dentry_kill(): don't bother with retain_dentry() on slow path ...
2024-01-11Merge tag 'pull-rename' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs Pull rename updates from Al Viro: "Fix directory locking scheme on rename This was broken in 6.5; we really can't lock two unrelated directories without holding ->s_vfs_rename_mutex first and in case of same-parent rename of a subdirectory 6.5 ends up doing just that" * tag 'pull-rename' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: rename(): avoid a deadlock in the case of parents having no common ancestor kill lock_two_inodes() rename(): fix the locking of subdirectories f2fs: Avoid reading renamed directory if parent does not change ext4: don't access the source subdirectory content on same-directory rename ext2: Avoid reading renamed directory if parent does not change udf_rename(): only access the child content on cross-directory rename ocfs2: Avoid touching renamed directory if parent does not change reiserfs: Avoid touching renamed directory if parent does not change
2024-01-11Merge tag 'docs-6.8' of git://git.lwn.net/linuxLinus Torvalds
Pull documentation update from Jonathan Corbet: "Another moderately busy cycle for documentation, including: - The minimum Sphinx requirement has been raised to 2.4.4, following a warning that was added in 6.2 - Some reworking of the Documentation/process front page to, hopefully, make it more useful - Various kernel-doc tweaks to, for example, make it deal properly with __counted_by annotations - We have also restored a warning for documentation of nonexistent structure members that disappeared a while back. That had the delightful consequence of adding some 600 warnings to the docs build. A sustained effort by Randy, Vegard, and myself has addressed almost all of those, bringing the documentation back into sync with the code. The fixes are going through the appropriate maintainer trees - Various improvements to the HTML rendered docs, including automatic links to Git revisions and a nice new pulldown to make translations easy to access - Speaking of translations, more of those for Spanish and Chinese ... plus the usual stream of documentation updates and typo fixes" * tag 'docs-6.8' of git://git.lwn.net/linux: (57 commits) MAINTAINERS: use tabs for indent of CONFIDENTIAL COMPUTING THREAT MODEL A reworked process/index.rst ring-buffer/Documentation: Add documentation on buffer_percent file Translated the RISC-V architecture boot documentation. Docs: remove mentions of fdformat from util-linux Docs/zh_CN: Fix the meaning of DEBUG to pr_debug() Documentation: move driver-api/dcdbas to userspace-api/ Documentation: move driver-api/isapnp to userspace-api/ Documentation/core-api : fix typo in workqueue Documentation/trace: Fixed typos in the ftrace FLAGS section kernel-doc: handle a void function without producing a warning scripts/get_abi.pl: ignore some temp files docs: kernel_abi.py: fix command injection scripts/get_abi: fix source path leak CREDITS, MAINTAINERS, docs/process/howto: Update man-pages' maintainer docs: translations: add translations links when they exist kernel-doc: Align quick help and the code MAINTAINERS: add reviewer for Spanish translations docs: ignore __counted_by attribute in structure definitions scripts: kernel-doc: Clarify missing struct member description ..
2024-01-10Merge tag 'ovl-update-6.8' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/overlayfs/vfs Pull overlayfs updates from Amir Goldstein: "This is a very small update with no bug fixes and no new features. The larger update of overlayfs for this cycle, the re-factoring of overlayfs code into generic backing_file helpers, was already merged via Christian. Summary: - Simplify/clarify some code No bug fixes here, just some changes following questions from Al about overlayfs code that could be a little more simple to follow. - Overlayfs documentation style fixes Mainly fixes for ReST formatting suggested by documentation developers" * tag 'ovl-update-6.8' of git://git.kernel.org/pub/scm/linux/kernel/git/overlayfs/vfs: overlayfs.rst: fix ReST formatting overlayfs.rst: use consistent feature names ovl: initialize ovl_copy_up_ctx.destname inside ovl_do_copy_up() ovl: remove redundant ofs->indexdir member
2024-01-10Merge tag 'fscrypt-for-linus' of git://git.kernel.org/pub/scm/fs/fscrypt/linuxLinus Torvalds
Pull fscrypt updates from Eric Biggers: "Adjust the timing of the fscrypt keyring destruction, to prepare for btrfs's fscrypt support. Also document that CephFS supports fscrypt now" * tag 'fscrypt-for-linus' of git://git.kernel.org/pub/scm/fs/fscrypt/linux: fs: move fscrypt keyring destruction to after ->put_super f2fs: move release of block devices to after kill_block_super() fscrypt: document that CephFS supports fscrypt now fscrypt: update comment for do_remove_key() fscrypt.rst: update definition of struct fscrypt_context_v2
2024-01-10Merge tag 'xfs-6.8-merge-3' of git://git.kernel.org/pub/scm/fs/xfs/xfs-linuxLinus Torvalds
Pull xfs updates from Chandan Babu: "New features/functionality: - Online repair: - Reserve disk space for online repairs - Fix misinteraction between the AIL and btree bulkloader because of which the bulk load fails to queue a buffer for writeback if it happens to be on the AIL list - Prevent transaction reservation overflows when reaping blocks during online repair - Whenever possible, bulkloader now copies multiple records into a block - Support repairing of 1. Per-AG free space, inode and refcount btrees 2. Ondisk inodes 3. File data and attribute fork mappings - Verify the contents of 1. Inode and data fork of realtime bitmap file 2. Quota files - Introduce MF_MEM_PRE_REMOVE. This will be used to notify tasks about a pmem device being removed Bug fixes: - Fix memory leak of recovered attri intent items - Fix UAF during log intent recovery - Fix realtime geometry integer overflows - Prevent scrub from live locking in xchk_iget - Prevent fs shutdown when removing files during low free disk space - Prevent transaction reservation overflow when extending an RT device - Prevent incorrect warning from being printed when extending a filesystem - Fix an off-by-one error in xreap_agextent_binval - Serialize access to perag radix tree during deletion operation - Fix perag memory leak during growfs - Allow allocation of minlen realtime extent when the maximum sized realtime free extent is minlen in size Cleanups: - Remove duplicate boilerplate code spread across functionality associated with different log items - Cleanup resblks interfaces - Pass defer ops pointer to defer helpers instead of an enum - Initialize di_crc in xfs_log_dinode to prevent KMSAN warnings - Use static_assert() instead of BUILD_BUG_ON_MSG() to validate size of structures and structure member offsets. This is done in order to be able to share the code with userspace - Move XFS documentation under a new directory specific to XFS - Do not invoke deferred ops' ->create_done callback if the deferred operation does not have an intent item associated with it - Remove duplicate inclusion of header files from scrub/health.c - Refactor Realtime code - Cleanup attr code" * tag 'xfs-6.8-merge-3' of git://git.kernel.org/pub/scm/fs/xfs/xfs-linux: (123 commits) xfs: use the op name in trace_xlog_intent_recovery_failed xfs: fix a use after free in xfs_defer_finish_recovery xfs: turn the XFS_DA_OP_REPLACE checks in xfs_attr_shortform_addname into asserts xfs: remove xfs_attr_sf_hdr_t xfs: remove struct xfs_attr_shortform xfs: use xfs_attr_sf_findname in xfs_attr_shortform_getvalue xfs: remove xfs_attr_shortform_lookup xfs: simplify xfs_attr_sf_findname xfs: move the xfs_attr_sf_lookup tracepoint xfs: return if_data from xfs_idata_realloc xfs: make if_data a void pointer xfs: fold xfs_rtallocate_extent into xfs_bmap_rtalloc xfs: simplify and optimize the RT allocation fallback cascade xfs: reorder the minlen and prod calculations in xfs_bmap_rtalloc xfs: remove XFS_RTMIN/XFS_RTMAX xfs: remove rt-wrappers from xfs_format.h xfs: factor out a xfs_rtalloc_sumlevel helper xfs: tidy up xfs_rtallocate_extent_exact xfs: merge the calls to xfs_rtallocate_range in xfs_rtallocate_block xfs: reflow the tail end of xfs_rtallocate_extent_block ...
2024-01-09Merge tag 'mm-nonmm-stable-2024-01-09-10-33' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm Pull non-MM updates from Andrew Morton: "Quite a lot of kexec work this time around. Many singleton patches in many places. The notable patch series are: - nilfs2 folio conversion from Matthew Wilcox in 'nilfs2: Folio conversions for file paths'. - Additional nilfs2 folio conversion from Ryusuke Konishi in 'nilfs2: Folio conversions for directory paths'. - IA64 remnant removal in Heiko Carstens's 'Remove unused code after IA-64 removal'. - Arnd Bergmann has enabled the -Wmissing-prototypes warning everywhere in 'Treewide: enable -Wmissing-prototypes'. This had some followup fixes: - Nathan Chancellor has cleaned up the hexagon build in the series 'hexagon: Fix up instances of -Wmissing-prototypes'. - Nathan also addressed some s390 warnings in 's390: A couple of fixes for -Wmissing-prototypes'. - Arnd Bergmann addresses the same warnings for MIPS in his series 'mips: address -Wmissing-prototypes warnings'. - Baoquan He has made kexec_file operate in a top-down-fitting manner similar to kexec_load in the series 'kexec_file: Load kernel at top of system RAM if required' - Baoquan He has also added the self-explanatory 'kexec_file: print out debugging message if required'. - Some checkstack maintenance work from Tiezhu Yang in the series 'Modify some code about checkstack'. - Douglas Anderson has disentangled the watchdog code's logging when multiple reports are occurring simultaneously. The series is 'watchdog: Better handling of concurrent lockups'. - Yuntao Wang has contributed some maintenance work on the crash code in 'crash: Some cleanups and fixes'" * tag 'mm-nonmm-stable-2024-01-09-10-33' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (157 commits) crash_core: fix and simplify the logic of crash_exclude_mem_range() x86/crash: use SZ_1M macro instead of hardcoded value x86/crash: remove the unused image parameter from prepare_elf_headers() kdump: remove redundant DEFAULT_CRASH_KERNEL_LOW_SIZE scripts/decode_stacktrace.sh: strip unexpected CR from lines watchdog: if panicking and we dumped everything, don't re-enable dumping watchdog/hardlockup: use printk_cpu_sync_get_irqsave() to serialize reporting watchdog/softlockup: use printk_cpu_sync_get_irqsave() to serialize reporting watchdog/hardlockup: adopt softlockup logic avoiding double-dumps kexec_core: fix the assignment to kimage->control_page x86/kexec: fix incorrect end address passed to kernel_ident_mapping_init() lib/trace_readwrite.c:: replace asm-generic/io with linux/io nilfs2: cpfile: fix some kernel-doc warnings stacktrace: fix kernel-doc typo scripts/checkstack.pl: fix no space expression between sp and offset x86/kexec: fix incorrect argument passed to kexec_dprintk() x86/kexec: use pr_err() instead of kexec_dprintk() when an error occurs nilfs2: add missing set_freezable() for freezable kthread kernel: relay: remove relay_file_splice_read dead code, doesn't work docs: submit-checklist: remove all of "make namespacecheck" ...
2024-01-09Merge tag 'mm-stable-2024-01-08-15-31' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm Pull MM updates from Andrew Morton: "Many singleton patches against the MM code. The patch series which are included in this merge do the following: - Peng Zhang has done some mapletree maintainance work in the series 'maple_tree: add mt_free_one() and mt_attr() helpers' 'Some cleanups of maple tree' - In the series 'mm: use memmap_on_memory semantics for dax/kmem' Vishal Verma has altered the interworking between memory-hotplug and dax/kmem so that newly added 'device memory' can more easily have its memmap placed within that newly added memory. - Matthew Wilcox continues folio-related work (including a few fixes) in the patch series 'Add folio_zero_tail() and folio_fill_tail()' 'Make folio_start_writeback return void' 'Fix fault handler's handling of poisoned tail pages' 'Convert aops->error_remove_page to ->error_remove_folio' 'Finish two folio conversions' 'More swap folio conversions' - Kefeng Wang has also contributed folio-related work in the series 'mm: cleanup and use more folio in page fault' - Jim Cromie has improved the kmemleak reporting output in the series 'tweak kmemleak report format'. - In the series 'stackdepot: allow evicting stack traces' Andrey Konovalov to permits clients (in this case KASAN) to cause eviction of no longer needed stack traces. - Charan Teja Kalla has fixed some accounting issues in the page allocator's atomic reserve calculations in the series 'mm: page_alloc: fixes for high atomic reserve caluculations'. - Dmitry Rokosov has added to the samples/ dorectory some sample code for a userspace memcg event listener application. See the series 'samples: introduce cgroup events listeners'. - Some mapletree maintanance work from Liam Howlett in the series 'maple_tree: iterator state changes'. - Nhat Pham has improved zswap's approach to writeback in the series 'workload-specific and memory pressure-driven zswap writeback'. - DAMON/DAMOS feature and maintenance work from SeongJae Park in the series 'mm/damon: let users feed and tame/auto-tune DAMOS' 'selftests/damon: add Python-written DAMON functionality tests' 'mm/damon: misc updates for 6.8' - Yosry Ahmed has improved memcg's stats flushing in the series 'mm: memcg: subtree stats flushing and thresholds'. - In the series 'Multi-size THP for anonymous memory' Ryan Roberts has added a runtime opt-in feature to transparent hugepages which improves performance by allocating larger chunks of memory during anonymous page faults. - Matthew Wilcox has also contributed some cleanup and maintenance work against eh buffer_head code int he series 'More buffer_head cleanups'. - Suren Baghdasaryan has done work on Andrea Arcangeli's series 'userfaultfd move option'. UFFDIO_MOVE permits userspace heap compaction algorithms to move userspace's pages around rather than UFFDIO_COPY'a alloc/copy/free. - Stefan Roesch has developed a 'KSM Advisor', in the series 'mm/ksm: Add ksm advisor'. This is a governor which tunes KSM's scanning aggressiveness in response to userspace's current needs. - Chengming Zhou has optimized zswap's temporary working memory use in the series 'mm/zswap: dstmem reuse optimizations and cleanups'. - Matthew Wilcox has performed some maintenance work on the writeback code, both code and within filesystems. The series is 'Clean up the writeback paths'. - Andrey Konovalov has optimized KASAN's handling of alloc and free stack traces for secondary-level allocators, in the series 'kasan: save mempool stack traces'. - Andrey also performed some KASAN maintenance work in the series 'kasan: assorted clean-ups'. - David Hildenbrand has gone to town on the rmap code. Cleanups, more pte batching, folio conversions and more. See the series 'mm/rmap: interface overhaul'. - Kinsey Ho has contributed some maintenance work on the MGLRU code in the series 'mm/mglru: Kconfig cleanup'. - Matthew Wilcox has contributed lruvec page accounting code cleanups in the series 'Remove some lruvec page accounting functions'" * tag 'mm-stable-2024-01-08-15-31' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (361 commits) mm, treewide: rename MAX_ORDER to MAX_PAGE_ORDER mm, treewide: introduce NR_PAGE_ORDERS selftests/mm: add separate UFFDIO_MOVE test for PMD splitting selftests/mm: skip test if application doesn't has root privileges selftests/mm: conform test to TAP format output selftests: mm: hugepage-mmap: conform to TAP format output selftests/mm: gup_test: conform test to TAP format output mm/selftests: hugepage-mremap: conform test to TAP format output mm/vmstat: move pgdemote_* out of CONFIG_NUMA_BALANCING mm: zsmalloc: return -ENOSPC rather than -EINVAL in zs_malloc while size is too large mm/memcontrol: remove __mod_lruvec_page_state() mm/khugepaged: use a folio more in collapse_file() slub: use a folio in __kmalloc_large_node slub: use folio APIs in free_large_kmalloc() slub: use alloc_pages_node() in alloc_slab_page() mm: remove inc/dec lruvec page state functions mm: ratelimit stat flush from workingset shrinker kasan: stop leaking stack trace handles mm/mglru: remove CONFIG_TRANSPARENT_HUGEPAGE mm/mglru: add dummy pmd_dirty() ...
2024-01-08Merge tag 'vfs-6.8.super' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs Pull vfs super updates from Christian Brauner: "This contains the super work for this cycle including the long-awaited series by Jan to make it possible to prevent writing to mounted block devices: - Writing to mounted devices is dangerous and can lead to filesystem corruption as well as crashes. Furthermore syzbot comes with more and more involved examples how to corrupt block device under a mounted filesystem leading to kernel crashes and reports we can do nothing about. Add tracking of writers to each block device and a kernel cmdline argument which controls whether other writeable opens to block devices open with BLK_OPEN_RESTRICT_WRITES flag are allowed. Note that this effectively only prevents modification of the particular block device's page cache by other writers. The actual device content can still be modified by other means - e.g. by issuing direct scsi commands, by doing writes through devices lower in the storage stack (e.g. in case loop devices, DM, or MD are involved) etc. But blocking direct modifications of the block device page cache is enough to give filesystems a chance to perform data validation when loading data from the underlying storage and thus prevent kernel crashes. Syzbot can use this cmdline argument option to avoid uninteresting crashes. Also users whose userspace setup does not need writing to mounted block devices can set this option for hardening. We expect that this will be interesting to quite a few workloads. Btrfs is currently opted out of this because they still haven't merged patches we require for this to work from three kernel releases ago. - Reimplement block device freezing and thawing as holder operations on the block device. This allows us to extend block device freezing to all devices associated with a superblock and not just the main device. It also allows us to remove get_active_super() and thus another function that scans the global list of superblocks. Freezing via additional block devices only works if the filesystem chooses to use @fs_holder_ops for these additional devices as well. That currently only includes ext4 and xfs. Earlier releases switched get_tree_bdev() and mount_bdev() to use @fs_holder_ops. The remaining nilfs2 open-coded version of mount_bdev() has been converted to rely on @fs_holder_ops as well. So block device freezing for the main block device will continue to work as before. There should be no regressions in functionality. The only special case is btrfs where block device freezing for the main block device never worked because sb->s_bdev isn't set. Block device freezing for btrfs can be fixed once they can switch to @fs_holder_ops but that can happen whenever they're ready" * tag 'vfs-6.8.super' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs: (27 commits) block: Fix a memory leak in bdev_open_by_dev() super: don't bother with WARN_ON_ONCE() super: massage wait event mechanism ext4: Block writes to journal device xfs: Block writes to log device fs: Block writes to mounted block devices btrfs: Do not restrict writes to btrfs devices block: Add config option to not allow writing to mounted devices block: Remove blkdev_get_by_*() functions bcachefs: Convert to bdev_open_by_path() fs: handle freezing from multiple devices fs: remove dead check nilfs2: simplify device handling fs: streamline thaw_super_locked ext4: simplify device handling xfs: simplify device handling fs: simplify setup_bdev_super() calls blkdev: comment fs_holder_ops porting: document block device freeze and thaw changes fs: remove unused helper ...
2023-12-26fscrypt: document that CephFS supports fscrypt nowEric Biggers
The help text for CONFIG_FS_ENCRYPTION and the fscrypt.rst documentation file both list the filesystems that support fscrypt. CephFS added support for fscrypt in v6.6, so add CephFS to the list. Link: https://lore.kernel.org/r/20231227045158.87276-1-ebiggers@kernel.org Signed-off-by: Eric Biggers <ebiggers@google.com>
2023-12-24netfs, fscache: Remove ->begin_cache_operationDavid Howells
Remove ->begin_cache_operation() in favour of just calling fscache directly. Signed-off-by: David Howells <dhowells@redhat.com> Reviewed-by: Jeff Layton <jlayton@kernel.org> cc: Christian Brauner <christian@brauner.io> cc: linux-fsdevel@vger.kernel.org cc: linux-cachefs@redhat.com
2023-12-20mm: thp: introduce multi-size THP sysfs interfaceRyan Roberts
In preparation for adding support for anonymous multi-size THP, introduce new sysfs structure that will be used to control the new behaviours. A new directory is added under transparent_hugepage for each supported THP size, and contains an `enabled` file, which can be set to "inherit" (to inherit the global setting), "always", "madvise" or "never". For now, the kernel still only supports PMD-sized anonymous THP, so only 1 directory is populated. The first half of the change converts transhuge_vma_suitable() and hugepage_vma_check() so that they take a bitfield of orders for which the user wants to determine support, and the functions filter out all the orders that can't be supported, given the current sysfs configuration and the VMA dimensions. The resulting functions are renamed to thp_vma_suitable_orders() and thp_vma_allowable_orders() respectively. Convenience functions that take a single, unencoded order and return a boolean are also defined as thp_vma_suitable_order() and thp_vma_allowable_order(). The second half of the change implements the new sysfs interface. It has been done so that each supported THP size has a `struct thpsize`, which describes the relevant metadata and is itself a kobject. This is pretty minimal for now, but should make it easy to add new per-thpsize files to the interface if needed in future (e.g. per-size defrag). Rather than keep the `enabled` state directly in the struct thpsize, I've elected to directly encode it into huge_anon_orders_[always|madvise|inherit] bitfields since this reduces the amount of work required in thp_vma_allowable_orders() which is called for every page fault. See Documentation/admin-guide/mm/transhuge.rst, as modified by this commit, for details of how the new sysfs interface works. [ryan.roberts@arm.com: fix build warning when CONFIG_SYSFS is disabled] Link: https://lkml.kernel.org/r/20231211125320.3997543-1-ryan.roberts@arm.com Link: https://lkml.kernel.org/r/20231207161211.2374093-4-ryan.roberts@arm.com Signed-off-by: Ryan Roberts <ryan.roberts@arm.com> Reviewed-by: Barry Song <v-songbaohua@oppo.com> Tested-by: Kefeng Wang <wangkefeng.wang@huawei.com> Tested-by: John Hubbard <jhubbard@nvidia.com> Acked-by: David Hildenbrand <david@redhat.com> Cc: Alistair Popple <apopple@nvidia.com> Cc: Anshuman Khandual <anshuman.khandual@arm.com> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: David Rientjes <rientjes@google.com> Cc: "Huang, Ying" <ying.huang@intel.com> Cc: Hugh Dickins <hughd@google.com> Cc: Itaru Kitayama <itaru.kitayama@gmail.com> Cc: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Cc: Luis Chamberlain <mcgrof@kernel.org> Cc: Matthew Wilcox (Oracle) <willy@infradead.org> Cc: Vlastimil Babka <vbabka@suse.cz> Cc: Yang Shi <shy828301@gmail.com> Cc: Yin Fengwei <fengwei.yin@intel.com> Cc: Yu Zhao <yuzhao@google.com> Cc: Zi Yan <ziy@nvidia.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-12-15overlayfs.rst: fix ReST formattingAmir Goldstein
Fix some indentation issues and fix missing newlines in quoted text by converting quoted text to code blocks. Reported-by: Christian Brauner <brauner@kernel.org> Suggested-by: Bagas Sanjaya <bagasdotme@gmail.com> Reviewed-by: Bagas Sanjaya <bagasdotme@gmail.com> Reviewed-by: Akira Yokosawa <akiyks@gmail.com> Signed-off-by: Amir Goldstein <amir73il@gmail.com>
2023-12-14overlayfs.rst: use consistent feature namesAmir Goldstein
Use the feature names "metacopy" and "index" consistently throughout the document. Covert the numbered list of features "redirect_dir", "index", "xino" to section headings, so that those features could be referenced in the document by their name. Reviewed-by: Bagas Sanjaya <bagasdotme@gmail.com> Signed-off-by: Amir Goldstein <amir73il@gmail.com>
2023-12-10docs: filesystems: document the squashfs specific mount optionsAriel Miculas
When SQUASHFS_CHOICE_DECOMP_BY_MOUNT is set, the "threads" mount option can be used to specify the decompression mode: single-threaded, multi-threaded, percpu or the number of threads used for decompression. When SQUASHFS_CHOICE_DECOMP_BY_MOUNT is not set, SQUASHFS_DECOMP_MULTI and SQUASHFS_MOUNT_DECOMP_THREADS are both set, the "threads" option can also be used to specify the number of threads used for decompression. This mount option is only mentioned in fs/squashfs/Kconfig, which makes it difficult to find. Another mount option available is "errors", which can be configured to panic the kernel when squashfs errors are encountered. Add both these options to the squashfs documentation, making them more noticeable. Link: https://lkml.kernel.org/r/20231117161215.140282-1-amiculas@cisco.com Signed-off-by: Ariel Miculas <amiculas@cisco.com> Reviewed-by: Bagas Sanjaya <bagasdotme@gmail.com> Reviewed-by: Phillip Lougher <phillip@squashfs.org.uk> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Serge Hallyn <serge@hallyn.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-12-10fs: convert error_remove_page to error_remove_folioMatthew Wilcox (Oracle)
There were already assertions that we were not passing a tail page to error_remove_page(), so make the compiler enforce that by converting everything to pass and use a folio. Link: https://lkml.kernel.org/r/20231117161447.2461643-7-willy@infradead.org Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org> Cc: Naoya Horiguchi <naoya.horiguchi@nec.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-12-09fscrypt.rst: update definition of struct fscrypt_context_v2Eric Biggers
Get the copy of the fscrypt_context_v2 definition in the documentation in sync with the actual definition, which was changed recently by commit 5b1188847180 ("fscrypt: support crypto data unit size less than filesystem block size"). Link: https://lore.kernel.org/r/20231206001901.14371-1-ebiggers@kernel.org Signed-off-by: Eric Biggers <ebiggers@google.com>
2023-12-07Documentation: xfs: consolidate XFS docs into its own subdirectoryBagas Sanjaya
XFS docs are currently in upper-level Documentation/filesystems. Although these are currently 4 docs, they are already outstanding as a group and can be moved to its own subdirectory. Consolidate them into Documentation/filesystems/xfs/. Signed-off-by: Bagas Sanjaya <bagasdotme@gmail.com> Reviewed-by: Bill O'Donnell <bodonnel@redhat.com> Reviewed-by: "Darrick J. Wong" <djwong@kernel.org> Signed-off-by: Chandan Babu R <chandanbabu@kernel.org>
2023-12-04docs/fuse-io: Document the usage of DIRECT_IO_ALLOW_MMAPTyler Fanelli
By default, shared mmap is disabled in FUSE DIRECT_IO mode. However, when the DIRECT_IO_ALLOW_MMAP flag is enabled in the FUSE_INIT reply, shared mmap is allowed. Signed-off-by: Tyler Fanelli <tfanelli@redhat.com> Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
2023-11-25rename(): avoid a deadlock in the case of parents having no common ancestorAl Viro
... and fix the directory locking documentation and proof of correctness. Holding ->s_vfs_rename_mutex *almost* prevents ->d_parent changes; the case where we really don't want it is splicing the root of disconnected tree to somewhere. In other words, ->s_vfs_rename_mutex is sufficient to stabilize "X is an ancestor of Y" only if X and Y are already in the same tree. Otherwise it can go from false to true, and one can construct a deadlock on that. Make lock_two_directories() report an error in such case and update the callers of lock_rename()/lock_rename_child() to handle such errors. And yes, such conditions are not impossible to create ;-/ Reviewed-by: Jan Kara <jack@suse.cz> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2023-11-25rename(): fix the locking of subdirectoriesAl Viro
We should never lock two subdirectories without having taken ->s_vfs_rename_mutex; inode pointer order or not, the "order" proposed in 28eceeda130f "fs: Lock moved directories" is not transitive, with the usual consequences. The rationale for locking renamed subdirectory in all cases was the possibility of race between rename modifying .. in a subdirectory to reflect the new parent and another thread modifying the same subdirectory. For a lot of filesystems that's not a problem, but for some it can lead to trouble (e.g. the case when short directory contents is kept in the inode, but creating a file in it might push it across the size limit and copy its contents into separate data block(s)). However, we need that only in case when the parent does change - otherwise ->rename() doesn't need to do anything with .. entry in the first place. Some instances are lazy and do a tautological update anyway, but it's really not hard to avoid. Amended locking rules for rename(): find the parent(s) of source and target if source and target have the same parent lock the common parent else lock ->s_vfs_rename_mutex lock both parents, in ancestor-first order; if neither is an ancestor of another, lock the parent of source first. find the source and target. if source and target have the same parent if operation is an overwriting rename of a subdirectory lock the target subdirectory else if source is a subdirectory lock the source if target is a subdirectory lock the target lock non-directories involved, in inode pointer order if both source and target are such. That way we are guaranteed that parents are locked (for obvious reasons), that any renamed non-directory is locked (nfsd relies upon that), that any victim is locked (emptiness check needs that, among other things) and subdirectory that changes parent is locked (needed to protect the update of .. entries). We are also guaranteed that any operation locking more than one directory either takes ->s_vfs_rename_mutex or locks a parent followed by its child. Cc: stable@vger.kernel.org Fixes: 28eceeda130f "fs: Lock moved directories" Reviewed-by: Jan Kara <jack@suse.cz> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2023-11-25__dentry_kill(): new locking schemeAl Viro
Currently we enter __dentry_kill() with parent (along with the victim dentry and victim's inode) held locked. Then we mark dentry refcount as dead call ->d_prune() remove dentry from hash remove it from the parent's list of children unlock the parent, don't need it from that point on detach dentry from inode, unlock dentry and drop the inode (via ->d_iput()) call ->d_release() regain the lock on dentry check if it's on a shrink list (in which case freeing its empty husk has to be left to shrink_dentry_list()) or not (in which case we can free it ourselves). In the former case, mark it as an empty husk, so that shrink_dentry_list() would know it can free the sucker. drop the lock on dentry ... and usually the caller proceeds to drop a reference on the parent, possibly retaking the lock on it. That is painful for a bunch of reasons, starting with the need to take locks out of order, but not limited to that - the parent of positive dentry can change if we drop its ->d_lock, so getting these locks has to be done with care. Moreover, as soon as dentry is out of the parent's list of children, shrink_dcache_for_umount() won't see it anymore, making it appear as if the parent is inexplicably busy. We do work around that by having shrink_dentry_list() decrement the parent's refcount first and put it on shrink list to be evicted once we are done with __dentry_kill() of child, but that may in some cases lead to ->d_iput() on child called after the parent got killed. That doesn't happen in cases where in-tree ->d_iput() instances might want to look at the parent, but that's brittle as hell. Solution: do removal from the parent's list of children in the very end of __dentry_kill(). As the result, the callers do not need to lock the parent and by the time we really need the parent locked, dentry is negative and is guaranteed not to be moved around. It does mean that ->d_prune() will be called with parent not locked. It also means that we might see dentries in process of being torn down while going through the parent's list of children; those dentries will be unhashed, negative and with refcount marked dead. In practice, that's enough for in-tree code that looks through the list of children to do the right thing as-is. Out-of-tree code might need to be adjusted. Calling conventions: __dentry_kill(dentry) is called with dentry->d_lock held, along with ->i_lock of its inode (if any). It either returns the parent (locked, with refcount decremented to 0) or NULL (if there'd been no parent or if refcount decrement for parent hadn't reached 0). lock_for_kill() is adjusted for new requirements - it doesn't touch the parent's ->d_lock at all. Callers adjusted. Note that for dput() we don't need to bother with fast_dput() for the parent - we just need to check retain_dentry() for it, since its ->d_lock is still held since the moment when __dentry_kill() had taken it to remove the victim from the list of children. The kludge with early decrement of parent's refcount in shrink_dentry_list() is no longer needed - shrink_dcache_for_umount() sees the half-killed dentries in the list of children for as long as they are pinning the parent. They are easily recognized and accounted for by select_collect(), so we know we are not done yet. As the result, we always have the expected ordering for ->d_iput()/->d_release() vs. __dentry_kill() of the parent, no exceptions. Moreover, the current rules for shrink lists (one must make sure that shrink_dcache_for_umount() won't happen while any dentries from the superblock in question are on any shrink lists) are gone - shrink_dcache_for_umount() will do the right thing in all cases, taking such dentries out. Their empty husks (memory occupied by struct dentry itself + its external name, if any) will remain on the shrink lists, but they are no obstacles to filesystem shutdown. And such husks will get freed as soon as shrink_dentry_list() of the list they are on gets to them. Reviewed-by: Christian Brauner <brauner@kernel.org> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2023-11-25Call retain_dentry() with refcount 0Al Viro
Instead of bumping it from 0 to 1, calling retain_dentry(), then decrementing it back to 0 (with ->d_lock held all the way through), just leave refcount at 0 through all of that. It will have a visible effect for ->d_delete() - now it can be called with refcount 0 instead of 1 and it can no longer play silly buggers with dropping/regaining ->d_lock. Not that any in-tree instances tried to (it's pretty hard to get right). Any out-of-tree ones will have to adjust (assuming they need any changes). Note that we do not need to extend rcu-critical area here - we have verified that refcount is non-negative after having grabbed ->d_lock, so nobody will be able to free dentry until they get into __dentry_kill(), which won't happen until they manage to grab ->d_lock. Reviewed-by: Christian Brauner <brauner@kernel.org> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2023-11-25dentry: switch the lists of children to hlistAl Viro
Saves a pointer per struct dentry and actually makes the things less clumsy. Cleaned the d_walk() and dcache_readdir() a bit by use of hlist_for_... iterators. A couple of new helpers - d_first_child() and d_next_sibling(), to make the expressions less awful. Reviewed-by: Christian Brauner <brauner@kernel.org> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2023-11-18porting: document block device freeze and thaw changesChristian Brauner
Link: https://lore.kernel.org/r/20230927-vfs-super-freeze-v1-7-ecc36d9ab4d9@kernel.org Link: https://lore.kernel.org/r/20231024-vfs-super-freeze-v2-9-599c19f4faac@kernel.org Reviewed-by: Darrick J. Wong <djwong@kernel.org> Reviewed-by: Jan Kara <jack@suse.cz> Signed-off-by: Christian Brauner <brauner@kernel.org>
2023-11-17docs: vfs: fix typo in struct xattr_handlersAriel Miculas
The structure is called struct xattr_handler, singular, not plural. Fixing the typo also makes it greppable with the whole word matching flag. Signed-off-by: Ariel Miculas <amiculas@cisco.com> Acked-by: Randy Dunlap <rdunlap@infradead.org> Signed-off-by: Jonathan Corbet <corbet@lwn.net> Message-ID: <20231027152101.226296-1-amiculas@cisco.com>
2023-11-17MAINTAINERS: erofs: add EROFS webpageGao Xiang
Add a new `W:` field of the EROFS entry points to the documentation site at <https://erofs.docs.kernel.org>. In addition, update the in-tree documentation and Kconfig too. Signed-off-by: Gao Xiang <hsiangkao@linux.alibaba.com> Link: https://lore.kernel.org/r/20231117085329.1624223-1-hsiangkao@linux.alibaba.com
2023-11-07Merge tag 'vfs-6.7.fsid' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs Pull vfs fanotify fsid updates from Christian Brauner: "This work is part of the plan to enable fanotify to serve as a drop-in replacement for inotify. While inotify is availabe on all filesystems, fanotify currently isn't. In order to support fanotify on all filesystems two things are needed: (1) all filesystems need to support AT_HANDLE_FID (2) all filesystems need to report a non-zero f_fsid This contains (1) and allows filesystems to encode non-decodable file handlers for fanotify without implementing any exportfs operations by encoding a file id of type FILEID_INO64_GEN from i_ino and i_generation. Filesystems that want to opt out of encoding non-decodable file ids for fanotify that don't support NFS export can do so by providing an empty export_operations struct. This also partially addresses (2) by generating f_fsid for simple filesystems as well as freevxfs. Remaining filesystems will be dealt with by separate patches. Finally, this contains the patch from the current exportfs maintainers which moves exportfs under vfs with Chuck, Jeff, and Amir as maintainers and vfs.git as tree" * tag 'vfs-6.7.fsid' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs: MAINTAINERS: create an entry for exportfs fs: fix build error with CONFIG_EXPORTFS=m or not defined freevxfs: derive f_fsid from bdev->bd_dev fs: report f_fsid from s_dev for "simple" filesystems exportfs: support encoding non-decodeable file handles by default exportfs: define FILEID_INO64_GEN* file handle types exportfs: make ->encode_fh() a mandatory method for NFS export exportfs: add helpers to check if filesystem can encode/decode file handles
2023-11-07Merge tag 'ovl-update-6.7' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/overlayfs/vfs Pull overlayfs updates from Amir Goldstein: - Overlayfs aio cleanups and fixes Cleanups and minor fixes in preparation for factoring out of read/write passthrough code. - Overlayfs lock ordering changes Hold mnt_writers only throughout copy up instead of a long lived elevated refcount. - Add support for nesting overlayfs private xattrs There are cases where you want to use an overlayfs mount as a lowerdir for another overlayfs mount. For example, if the system rootfs is on overlayfs due to composefs, or to make it volatile (via tmpfs), then you cannot currently store a lowerdir on the rootfs, because the inner overlayfs will eat all the whiteouts and overlay xattrs. This means you can't e.g. store on the rootfs a prepared container image for use with overlayfs. This adds support for nesting of overlayfs mounts by escaping the problematic features and unescaping them when exposing to the overlayfs user. - Add new mount options for appending lowerdirs * tag 'ovl-update-6.7' of git://git.kernel.org/pub/scm/linux/kernel/git/overlayfs/vfs: ovl: add support for appending lowerdirs one by one ovl: refactor layer parsing helpers ovl: store and show the user provided lowerdir mount option ovl: remove unused code in lowerdir param parsing ovl: Add documentation on nesting of overlayfs mounts ovl: Add an alternative type of whiteout ovl: Support escaped overlay.* xattrs ovl: Add OVL_XATTR_TRUSTED/USER_PREFIX_LEN macros ovl: Move xattr support to new xattrs.c file ovl: do not encode lower fh with upper sb_writers held ovl: do not open/llseek lower file with upper sb_writers held ovl: reorder ovl_want_write() after ovl_inode_lock() ovl: split ovl_want_write() into two helpers ovl: add helper ovl_file_modified() ovl: protect copying of realinode attributes to ovl inode ovl: punt write aio completion to workqueue ovl: propagate IOCB_APPEND flag on writes to realfile ovl: use simpler function to convert iocb to rw flags
2023-11-02Merge tag 'erofs-for-6.7-rc1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/xiang/erofs Pull erofs updates from Gao Xiang: "Nothing exciting lands for this cycle, since we're still busying in developing support for sub-page blocks and large-folios of compressed data for new scenarios on Android. In this cycle, MicroLZMA format is marked as stable, and there are minor cleanups around documentation and codebase. In addition, it also fixes incorrect lockref usage in erofs_insert_workgroup(). Summary: - Fix inode metadata space layout documentation - Avoid warning for MicroLZMA format anymore - Fix erofs_insert_workgroup() lockref usage - Some cleanups" * tag 'erofs-for-6.7-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/xiang/erofs: erofs: fix erofs_insert_workgroup() lockref usage erofs: tidy up redundant includes erofs: get rid of ROOT_NID() erofs: simplify compression configuration parser erofs: don't warn MicroLZMA format anymore erofs: fix inode metadata space layout description in documentation
2023-11-01Merge tag 'docs-6.7' of git://git.lwn.net/linuxLinus Torvalds
Pull documentation updates from Jonathan Corbet: "The number of commits for documentation is not huge this time around, but there are some significant changes nonetheless: - Some more Spanish-language and Chinese translations - The much-discussed documentation of the confidential-computing threat model - Powerpc and RISCV documentation move under Documentation/arch - these complete this particular bit of documentation churn - A large traditional-Chinese documentation update - A new document on backporting and conflict resolution - Some kernel-doc and Sphinx fixes Plus the usual smattering of smaller updates and typo fixes" * tag 'docs-6.7' of git://git.lwn.net/linux: (40 commits) scripts/kernel-doc: Fix the regex for matching -Werror flag docs: backporting: address feedback Documentation: driver-api: pps: Update PPS generator documentation speakup: Document USB support doc: blk-ioprio: Bring the doc in line with the implementation docs: usb: fix reference to nonexistent file in UVC Gadget docs: doc-guide: mention 'make refcheckdocs' Documentation: fix typo in dynamic-debug howto scripts/kernel-doc: match -Werror flag strictly Documentation/sphinx: Remove the repeated word "the" in comments. docs: sparse: add SPDX-License-Identifier docs/zh_CN: Add subsystem-apis Chinese translation docs/zh_TW: update contents for zh_TW docs: submitting-patches: encourage direct notifications to commenters docs: add backporting and conflict resolution document docs: move riscv under arch docs: update link to powerpc/vmemmap_dedup.rst mm/memory-hotplug: fix typo in documentation docs: move powerpc under arch PCI: Update the devres documentation regarding to pcim_*() ...
2023-11-01Merge tag 'bootconfig-v6.7' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace Pull bootconfig updates from Masami Hiramatsu: - Documentation update for /proc/cmdline, which includes both the parameters from bootloader and the embedded parameters in the kernel - fs/proc: Add bootloader argument as a comment line to /proc/bootconfig so that the user can distinguish what parameters were passed from bootloader even if bootconfig modified that - Documentation fix to add /proc/bootconfig to proc.rst * tag 'bootconfig-v6.7' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace: doc: Add /proc/bootconfig to proc.rst fs/proc: Add boot loader arguments as comment to /proc/bootconfig doc: Update /proc/cmdline documentation to include boot config
2023-10-31doc: Add /proc/bootconfig to proc.rstPaul E. McKenney
Add /proc/bootconfig description to Documentation/filesystems/proc.rst. Link: https://lore.kernel.org/all/20231005171747.541123-3-paulmck@kernel.org/ Reported-by: Masami Hiramatsu <mhiramat@kernel.org> Signed-off-by: Paul E. McKenney <paulmck@kernel.org> Acked-by: Masami Hiramatsu (Google) <mhiramat@kernel.org> Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
2023-10-31ovl: add support for appending lowerdirs one by oneAmir Goldstein
Add new mount options lowerdir+ and datadir+ that can be used to add layers to lower layers stack one by one. Unlike the legacy lowerdir mount option, special characters (i.e. colons and cammas) are not unescaped with these new mount options. The new mount options can be repeated to compose a large stack of lower layers, but they may not be mixed with the lagacy lowerdir mount option, because for displaying lower layers in mountinfo, we do not want to mix escaped with unescaped lower layers path syntax. Similar to data-only layer rules with the lowerdir mount option, the datadir+ option must follow at least one lowerdir+ option and the lowerdir+ option must not follow the datadir+ option. If the legacy lowerdir mount option follows lowerdir+ and datadir+ mount options, it overrides them. Sepcifically, calling: fsconfig(FSCONFIG_SET_STRING, "lowerdir", "", 0); can be used to reset previously setup lower layers. Suggested-by: Miklos Szeredi <miklos@szeredi.hu> Link: https://lore.kernel.org/r/CAJfpegt7VC94KkRtb1dfHG8+4OzwPBLYqhtc8=QFUxpFJE+=RQ@mail.gmail.com/ Signed-off-by: Amir Goldstein <amir73il@gmail.com>
2023-10-31ovl: Add documentation on nesting of overlayfs mountsAlexander Larsson
Signed-off-by: Alexander Larsson <alexl@redhat.com> Reviewed-by: Amir Goldstein <amir73il@gmail.com> Signed-off-by: Amir Goldstein <amir73il@gmail.com>
2023-10-30Merge tag 'fscrypt-for-linus' of git://git.kernel.org/pub/scm/fs/fscrypt/linuxLinus Torvalds
Pull fscrypt updates from Eric Biggers: "This update adds support for configuring the crypto data unit size (i.e. the granularity of file contents encryption) to be less than the filesystem block size. This can allow users to use inline encryption hardware in some cases when it wouldn't otherwise be possible. In addition, there are two commits that are prerequisites for the extent-based encryption support that the btrfs folks are working on" * tag 'fscrypt-for-linus' of git://git.kernel.org/pub/scm/fs/fscrypt/linux: fscrypt: track master key presence separately from secret fscrypt: rename fscrypt_info => fscrypt_inode_info fscrypt: support crypto data unit size less than filesystem block size fscrypt: replace get_ino_and_lblk_bits with just has_32bit_inodes fscrypt: compute max_lblk_bits from s_maxbytes and block size fscrypt: make the bounce page pool opt-in instead of opt-out fscrypt: make it clearer that key_prefix is deprecated
2023-10-30Merge tag 'nfsd-6.7' of git://git.kernel.org/pub/scm/linux/kernel/git/cel/linuxLinus Torvalds
Pull nfsd updates from Chuck Lever: "This release completes the SunRPC thread scheduler work that was begun in v6.6. The scheduler can now find an svc thread to wake in constant time and without a list walk. Thanks again to Neil Brown for this overhaul. Lorenzo Bianconi contributed infrastructure for a netlink-based NFSD control plane. The long-term plan is to provide the same functionality as found in /proc/fs/nfsd, plus some interesting additions, and then migrate the NFSD user space utilities to netlink. A long series to overhaul NFSD's NFSv4 operation encoding was applied in this release. The goals are to bring this family of encoding functions in line with the matching NFSv4 decoding functions and with the NFSv2 and NFSv3 XDR functions, preparing the way for better memory safety and maintainability. A further improvement to NFSD's write delegation support was contributed by Dai Ngo. This adds a CB_GETATTR callback, enabling the server to retrieve cached size and mtime data from clients holding write delegations. If the server can retrieve this information, it does not have to recall the delegation in some cases. The usual panoply of bug fixes and minor improvements round out this release. As always I am grateful to all contributors, reviewers, and testers" * tag 'nfsd-6.7' of git://git.kernel.org/pub/scm/linux/kernel/git/cel/linux: (127 commits) svcrdma: Fix tracepoint printk format svcrdma: Drop connection after an RDMA Read error NFSD: clean up alloc_init_deleg() NFSD: Fix frame size warning in svc_export_parse() NFSD: Rewrite synopsis of nfsd_percpu_counters_init() nfsd: Clean up errors in nfs3proc.c nfsd: Clean up errors in nfs4state.c NFSD: Clean up errors in stats.c NFSD: simplify error paths in nfsd_svc() NFSD: Clean up nfsd4_encode_seek() NFSD: Clean up nfsd4_encode_offset_status() NFSD: Clean up nfsd4_encode_copy_notify() NFSD: Clean up nfsd4_encode_copy() NFSD: Clean up nfsd4_encode_test_stateid() NFSD: Clean up nfsd4_encode_exchange_id() NFSD: Clean up nfsd4_do_encode_secinfo() NFSD: Clean up nfsd4_encode_access() NFSD: Clean up nfsd4_encode_readdir() NFSD: Clean up nfsd4_encode_entry4() NFSD: Add an nfsd4_encode_nfs_cookie4() helper ...
2023-10-30Merge tag 'vfs-6.7.misc' of gitolite.kernel.org:pub/scm/linux/kernel/git/vfs/vfsLinus Torvalds
Pull misc vfs updates from Christian Brauner: "This contains the usual miscellaneous features, cleanups, and fixes for vfs and individual fses. Features: - Rename and export helpers that get write access to a mount. They are used in overlayfs to get write access to the upper mount. - Print the pretty name of the root device on boot failure. This helps in scenarios where we would usually only print "unknown-block(1,2)". - Add an internal SB_I_NOUMASK flag. This is another part in the endless POSIX ACL saga in a way. When POSIX ACLs are enabled via SB_POSIXACL the vfs cannot strip the umask because if the relevant inode has POSIX ACLs set it might take the umask from there. But if the inode doesn't have any POSIX ACLs set then we apply the umask in the filesytem itself. So we end up with: (1) no SB_POSIXACL -> strip umask in vfs (2) SB_POSIXACL -> strip umask in filesystem The umask semantics associated with SB_POSIXACL allowed filesystems that don't even support POSIX ACLs at all to raise SB_POSIXACL purely to avoid umask stripping. That specifically means NFS v4 and Overlayfs. NFS v4 does it because it delegates this to the server and Overlayfs because it needs to delegate umask stripping to the upper filesystem, i.e., the filesystem used as the writable layer. This went so far that SB_POSIXACL is raised eve on kernels that don't even have POSIX ACL support at all. Stop this blatant abuse and add SB_I_NOUMASK which is an internal superblock flag that filesystems can raise to opt out of umask handling. That should really only be the two mentioned above. It's not that we want any filesystems to do this. Ideally we have all umask handling always in the vfs. - Make overlayfs use SB_I_NOUMASK too. - Now that we have SB_I_NOUMASK, stop checking for SB_POSIXACL in IS_POSIXACL() if the kernel doesn't have support for it. This is a very old patch but it's only possible to do this now with the wider cleanup that was done. - Follow-up work on fake path handling from last cycle. Citing mostly from Amir: When overlayfs was first merged, overlayfs files of regular files and directories, the ones that are installed in file table, had a "fake" path, namely, f_path is the overlayfs path and f_inode is the "real" inode on the underlying filesystem. In v6.5, we took another small step by introducing of the backing_file container and the file_real_path() helper. This change allowed vfs and filesystem code to get the "real" path of an overlayfs backing file. With this change, we were able to make fsnotify work correctly and report events on the "real" filesystem objects that were accessed via overlayfs. This method works fine, but it still leaves the vfs vulnerable to new code that is not aware of files with fake path. A recent example is commit db1d1e8b9867 ("IMA: use vfs_getattr_nosec to get the i_version"). This commit uses direct referencing to f_path in IMA code that otherwise uses file_inode() and file_dentry() to reference the filesystem objects that it is measuring. This contains work to switch things around: instead of having filesystem code opt-in to get the "real" path, have generic code opt-in for the "fake" path in the few places that it is needed. Is it far more likely that new filesystems code that does not use the file_dentry() and file_real_path() helpers will end up causing crashes or averting LSM/audit rules if we keep the "fake" path exposed by default. This change already makes file_dentry() moot, but for now we did not change this helper just added a WARN_ON() in ovl_d_real() to catch if we have made any wrong assumptions. After the dust settles on this change, we can make file_dentry() a plain accessor and we can drop the inode argument to ->d_real(). - Switch struct file to SLAB_TYPESAFE_BY_RCU. This looks like a small change but it really isn't and I would like to see everyone on their tippie toes for any possible bugs from this work. Essentially we've been doing most of what SLAB_TYPESAFE_BY_RCU for files since a very long time because of the nasty interactions between the SCM_RIGHTS file descriptor garbage collection. So extending it makes a lot of sense but it is a subtle change. There are almost no places that fiddle with file rcu semantics directly and the ones that did mess around with struct file internal under rcu have been made to stop doing that because it really was always dodgy. I forgot to put in the link tag for this change and the discussion in the commit so adding it into the merge message: https://lore.kernel.org/r/20230926162228.68666-1-mjguzik@gmail.com Cleanups: - Various smaller pipe cleanups including the removal of a spin lock that was only used to protect against writes without pipe_lock() from O_NOTIFICATION_PIPE aka watch queues. As that was never implemented remove the additional locking from pipe_write(). - Annotate struct watch_filter with the new __counted_by attribute. - Clarify do_unlinkat() cleanup so that it doesn't look like an extra iput() is done that would cause issues. - Simplify file cleanup when the file has never been opened. - Use module helper instead of open-coding it. - Predict error unlikely for stale retry. - Use WRITE_ONCE() for mount expiry field instead of just commenting that one hopes the compiler doesn't get smart. Fixes: - Fix readahead on block devices. - Fix writeback when layztime is enabled and inodes whose timestamp is the only thing that changed reside on wb->b_dirty_time. This caused excessively large zombie memory cgroup when lazytime was enabled as such inodes weren't handled fast enough. - Convert BUG_ON() to WARN_ON_ONCE() in open_last_lookups()" * tag 'vfs-6.7.misc' of gitolite.kernel.org:pub/scm/linux/kernel/git/vfs/vfs: (26 commits) file, i915: fix file reference for mmap_singleton() vfs: Convert BUG_ON to WARN_ON_ONCE in open_last_lookups writeback, cgroup: switch inodes with dirty timestamps to release dying cgwbs chardev: Simplify usage of try_module_get() ovl: rely on SB_I_NOUMASK fs: fix umask on NFS with CONFIG_FS_POSIX_ACL=n fs: store real path instead of fake path in backing file f_path fs: create helper file_user_path() for user displayed mapped file path fs: get mnt_writers count for an open backing file's real path vfs: stop counting on gcc not messing with mnt_expiry_mark if not asked vfs: predict the error in retry_estale as unlikely backing file: free directly vfs: fix readahead(2) on block devices io_uring: use files_lookup_fd_locked() file: convert to SLAB_TYPESAFE_BY_RCU vfs: shave work on failed file open fs: simplify misleading code to remove ambiguity regarding ihold()/iput() watch_queue: Annotate struct watch_filter with __counted_by fs/pipe: use spinlock in pipe_read() only if there is a watch_queue fs/pipe: remove unnecessary spinlock from pipe_write() ...
2023-10-28exportfs: make ->encode_fh() a mandatory method for NFS exportAmir Goldstein
Rename the default helper for encoding FILEID_INO32_GEN* file handles to generic_encode_ino32_fh() and convert the filesystems that used the default implementation to use the generic helper explicitly. After this change, exportfs_encode_inode_fh() no longer has a default implementation to encode FILEID_INO32_GEN* file handles. This is a step towards allowing filesystems to encode non-decodeable file handles for fanotify without having to implement any export_operations. Reviewed-by: Jan Kara <jack@suse.cz> Reviewed-by: Jeff Layton <jlayton@kernel.org> Acked-by: Chuck Lever <chuck.lever@oracle.com> Signed-off-by: Amir Goldstein <amir73il@gmail.com> Link: https://lore.kernel.org/r/20231023180801.2953446-3-amir73il@gmail.com Acked-by: Dave Kleikamp <dave.kleikamp@oracle.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Christian Brauner <brauner@kernel.org>
2023-10-28porting: update locking requirementsChristian Brauner
Now that s_umount is never taken under open_mutex update the documentation to say so. Link: https://lore.kernel.org/r/20231017184823.1383356-1-hch@lst.de Signed-off-by: Christian Brauner <brauner@kernel.org>
2023-10-19file: convert to SLAB_TYPESAFE_BY_RCUChristian Brauner
In recent discussions around some performance improvements in the file handling area we discussed switching the file cache to rely on SLAB_TYPESAFE_BY_RCU which allows us to get rid of call_rcu() based freeing for files completely. This is a pretty sensitive change overall but it might actually be worth doing. The main downside is the subtlety. The other one is that we should really wait for Jann's patch to land that enables KASAN to handle SLAB_TYPESAFE_BY_RCU UAFs. Currently it doesn't but a patch for this exists. With SLAB_TYPESAFE_BY_RCU objects may be freed and reused multiple times which requires a few changes. So it isn't sufficient anymore to just acquire a reference to the file in question under rcu using atomic_long_inc_not_zero() since the file might have already been recycled and someone else might have bumped the reference. In other words, callers might see reference count bumps from newer users. For this reason it is necessary to verify that the pointer is the same before and after the reference count increment. This pattern can be seen in get_file_rcu() and __files_get_rcu(). In addition, it isn't possible to access or check fields in struct file without first aqcuiring a reference on it. Not doing that was always very dodgy and it was only usable for non-pointer data in struct file. With SLAB_TYPESAFE_BY_RCU it is necessary that callers first acquire a reference under rcu or they must hold the files_lock of the fdtable. Failing to do either one of this is a bug. Thanks to Jann for pointing out that we need to ensure memory ordering between reallocations and pointer check by ensuring that all subsequent loads have a dependency on the second load in get_file_rcu() and providing a fixup that was folded into this patch. Cc: Jann Horn <jannh@google.com> Suggested-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Christian Brauner <brauner@kernel.org>