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2023-07-19fs: Lock moved directoriesJan Kara
commit 28eceeda130f5058074dd007d9c59d2e8bc5af2e upstream. When a directory is moved to a different directory, some filesystems (udf, ext4, ocfs2, f2fs, and likely gfs2, reiserfs, and others) need to update their pointer to the parent and this must not race with other operations on the directory. Lock the directories when they are moved. Although not all filesystems need this locking, we perform it in vfs_rename() because getting the lock ordering right is really difficult and we don't want to expose these locking details to filesystems. CC: stable@vger.kernel.org Signed-off-by: Jan Kara <jack@suse.cz> Message-Id: <20230601105830.13168-5-jack@suse.cz> Signed-off-by: Christian Brauner <brauner@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-07-19autofs: use flexible array in ioctl structureArnd Bergmann
commit e910c8e3aa02dc456e2f4c32cb479523c326b534 upstream. Commit df8fc4e934c1 ("kbuild: Enable -fstrict-flex-arrays=3") introduced a warning for the autofs_dev_ioctl structure: In function 'check_name', inlined from 'validate_dev_ioctl' at fs/autofs/dev-ioctl.c:131:9, inlined from '_autofs_dev_ioctl' at fs/autofs/dev-ioctl.c:624:8: fs/autofs/dev-ioctl.c:33:14: error: 'strchr' reading 1 or more bytes from a region of size 0 [-Werror=stringop-overread] 33 | if (!strchr(name, '/')) | ^~~~~~~~~~~~~~~~~ In file included from include/linux/auto_dev-ioctl.h:10, from fs/autofs/autofs_i.h:10, from fs/autofs/dev-ioctl.c:14: include/uapi/linux/auto_dev-ioctl.h: In function '_autofs_dev_ioctl': include/uapi/linux/auto_dev-ioctl.h:112:14: note: source object 'path' of size 0 112 | char path[0]; | ^~~~ This is easily fixed by changing the gnu 0-length array into a c99 flexible array. Since this is a uapi structure, we have to be careful about possible regressions but this one should be fine as they are equivalent here. While it would break building with ancient gcc versions that predate c99, it helps building with --std=c99 and -Wpedantic builds in user space, as well as non-gnu compilers. This means we probably also want it fixed in stable kernels. Cc: stable@vger.kernel.org Cc: Kees Cook <keescook@chromium.org> Cc: "Gustavo A. R. Silva" <gustavoars@kernel.org> Signed-off-by: Arnd Bergmann <arnd@arndb.de> Signed-off-by: Kees Cook <keescook@chromium.org> Link: https://lore.kernel.org/r/20230523081944.581710-1-arnd@kernel.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-03-22docs: Correct missing "d_" prefix for dentry_operations member d_weak_revalidateGlenn Washburn
[ Upstream commit 74596085796fae0cfce3e42ee46bf4f8acbdac55 ] The details for struct dentry_operations member d_weak_revalidate is missing a "d_" prefix. Fixes: af96c1e304f7 ("docs: filesystems: vfs: Convert vfs.txt to RST") Signed-off-by: Glenn Washburn <development@efficientek.com> Reviewed-by: Matthew Wilcox (Oracle) <willy@infradead.org> Link: https://lore.kernel.org/r/20230227184042.2375235-1-development@efficientek.com Signed-off-by: Jonathan Corbet <corbet@lwn.net> Signed-off-by: Sasha Levin <sashal@kernel.org>
2023-01-07ext4: journal_path mount options should follow linksLukas Czerner
commit e3ea75ee651daf5e434afbfdb7dbf75e200ea1f6 upstream. Before the commit 461c3af045d3 ("ext4: Change handle_mount_opt() to use fs_parameter") ext4 mount option journal_path did follow links in the provided path. Bring this behavior back by allowing to pass pathwalk flags to fs_lookup_param(). Fixes: 461c3af045d3 ("ext4: Change handle_mount_opt() to use fs_parameter") Signed-off-by: Lukas Czerner <lczerner@redhat.com> Reviewed-by: Darrick J. Wong <djwong@kernel.org> Link: https://lore.kernel.org/r/20221004135803.32283-1-lczerner@redhat.com Signed-off-by: Theodore Ts'o <tytso@mit.edu> Cc: stable@kernel.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-10-13Merge tag 'docs-6.1-2' of git://git.lwn.net/linuxLinus Torvalds
Pull documentation fixes from Jonathan Corbet: "A handful of relatively simple documentation fixes, plus a set of patches catching the Chinese translation up with the front-page rework" * tag 'docs-6.1-2' of git://git.lwn.net/linux: Documentation: rtla: Correct command line example docs/zh_CN: add a man-pages link to zh_CN/index.rst docs/zh_CN: Rewrite the Chinese translation front page docs/zh_CN: add zh_CN/arch.rst docs/zh_CN: promote the title of zh_CN/process/index.rst docs/zh_CN: Update the translation of page_owner to 6.0-rc7 docs/zh_CN: Update the translation of ksm to 6.0-rc7 docs/howto: Replace abundoned URL of gmane.org Documentation: ubifs: Fix compression idiom Documentation/mm/page_owner.rst: delete frequently changing experimental data docs/zh_CN: Fix build warning docs: ftrace: Correct access mode
2022-10-13Merge tag 'ceph-for-6.1-rc1' of https://github.com/ceph/ceph-clientLinus Torvalds
Pull ceph updates from Ilya Dryomov: "A quiet round this time: several assorted filesystem fixes, the most noteworthy one being some additional wakeups in cap handling code, and a messenger cleanup" * tag 'ceph-for-6.1-rc1' of https://github.com/ceph/ceph-client: ceph: remove Sage's git tree from documentation ceph: fix incorrectly showing the .snap size for stat ceph: fail the open_by_handle_at() if the dentry is being unlinked ceph: increment i_version when doing a setattr with caps ceph: Use kcalloc for allocating multiple elements ceph: no need to wait for transition RDCACHE|RD -> RD ceph: fail the request if the peer MDS doesn't support getvxattr op ceph: wake up the waiters if any new caps comes libceph: drop last_piece flag from ceph_msg_data_cursor
2022-10-10Merge tag 'pull-tmpfile' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs Pull vfs tmpfile updates from Al Viro: "Miklos' ->tmpfile() signature change; pass an unopened struct file to it, let it open the damn thing. Allows to add tmpfile support to FUSE" * tag 'pull-tmpfile' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: fuse: implement ->tmpfile() vfs: open inside ->tmpfile() vfs: move open right after ->tmpfile() vfs: make vfs_tmpfile() static ovl: use vfs_tmpfile_open() helper cachefiles: use vfs_tmpfile_open() helper cachefiles: only pass inode to *mark_inode_inuse() helpers cachefiles: tmpfile error handling cleanup hugetlbfs: cleanup mknod and tmpfile vfs: add vfs_tmpfile_open() helper
2022-10-10Documentation: ubifs: Fix compression idiomJoel Stanley
Clearly the author meant 'on the fly'. Signed-off-by: Joel Stanley <joel@jms.id.au> Link: https://lore.kernel.org/r/20221005030904.65604-1-joel@jms.id.au Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2022-10-09Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvmLinus Torvalds
Pull kvm updates from Paolo Bonzini: "The first batch of KVM patches, mostly covering x86. ARM: - Account stage2 page table allocations in memory stats x86: - Account EPT/NPT arm64 page table allocations in memory stats - Tracepoint cleanups/fixes for nested VM-Enter and emulated MSR accesses - Drop eVMCS controls filtering for KVM on Hyper-V, all known versions of Hyper-V now support eVMCS fields associated with features that are enumerated to the guest - Use KVM's sanitized VMCS config as the basis for the values of nested VMX capabilities MSRs - A myriad event/exception fixes and cleanups. Most notably, pending exceptions morph into VM-Exits earlier, as soon as the exception is queued, instead of waiting until the next vmentry. This fixed a longstanding issue where the exceptions would incorrecly become double-faults instead of triggering a vmexit; the common case of page-fault vmexits had a special workaround, but now it's fixed for good - A handful of fixes for memory leaks in error paths - Cleanups for VMREAD trampoline and VMX's VM-Exit assembly flow - Never write to memory from non-sleepable kvm_vcpu_check_block() - Selftests refinements and cleanups - Misc typo cleanups Generic: - remove KVM_REQ_UNHALT" * tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (94 commits) KVM: remove KVM_REQ_UNHALT KVM: mips, x86: do not rely on KVM_REQ_UNHALT KVM: x86: never write to memory from kvm_vcpu_check_block() KVM: x86: Don't snapshot pending INIT/SIPI prior to checking nested events KVM: nVMX: Make event request on VMXOFF iff INIT/SIPI is pending KVM: nVMX: Make an event request if INIT or SIPI is pending on VM-Enter KVM: SVM: Make an event request if INIT or SIPI is pending when GIF is set KVM: x86: lapic does not have to process INIT if it is blocked KVM: x86: Rename kvm_apic_has_events() to make it INIT/SIPI specific KVM: x86: Rename and expose helper to detect if INIT/SIPI are allowed KVM: nVMX: Make an event request when pending an MTF nested VM-Exit KVM: x86: make vendor code check for all nested events mailmap: Update Oliver's email address KVM: x86: Allow force_emulation_prefix to be written without a reload KVM: selftests: Add an x86-only test to verify nested exception queueing KVM: selftests: Use uapi header to get VMX and SVM exit reasons/codes KVM: x86: Rename inject_pending_events() to kvm_check_and_inject_events() KVM: VMX: Update MTF and ICEBP comments to document KVM's subtle behavior KVM: x86: Treat pending TRIPLE_FAULT requests as pending exceptions KVM: x86: Morph pending exceptions to pending VM-Exits at queue time ...
2022-10-07Merge tag 'driver-core-6.1-rc1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core Pull driver core updates from Greg KH: "Here is the big set of driver core and debug printk changes for 6.1-rc1. Included in here is: - dynamic debug updates for the core and the drm subsystem. The drm changes have all been acked by the relevant maintainers - kernfs fixes for syzbot reported problems - kernfs refactors and updates for cgroup requirements - magic number cleanups and removals from the kernel tree (they were not being used and they really did not actually do anything) - other tiny cleanups All of these have been in linux-next for a while with no reported issues" * tag 'driver-core-6.1-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core: (74 commits) docs: filesystems: sysfs: Make text and code for ->show() consistent Documentation: NBD_REQUEST_MAGIC isn't a magic number a.out: restore CMAGIC device property: Add const qualifier to device_get_match_data() parameter drm_print: add _ddebug descriptor to drm_*dbg prototypes drm_print: prefer bare printk KERN_DEBUG on generic fn drm_print: optimize drm_debug_enabled for jump-label drm-print: add drm_dbg_driver to improve namespace symmetry drm-print.h: include dyndbg header drm_print: wrap drm_*_dbg in dyndbg descriptor factory macro drm_print: interpose drm_*dbg with forwarding macros drm: POC drm on dyndbg - use in core, 2 helpers, 3 drivers. drm_print: condense enum drm_debug_category debugfs: use DEFINE_SHOW_ATTRIBUTE to define debugfs_regset32_fops driver core: use IS_ERR_OR_NULL() helper in device_create_groups_vargs() Documentation: ENI155_MAGIC isn't a magic number Documentation: NBD_REPLY_MAGIC isn't a magic number nbd: remove define-only NBD_MAGIC, previously magic number Documentation: FW_HEADER_MAGIC isn't a magic number Documentation: EEPROM_MAGIC_VALUE isn't a magic number ...
2022-10-07Merge tag '6.1-rc-ksmbd-fixes' of git://git.samba.org/ksmbdLinus Torvalds
Pull ksmbd updates from Steve French: - RDMA (smbdirect) fixes - fixes for SMB3.1.1 POSIX Extensions (especially for id mapping) - various casemapping fixes for mount and lookup - UID mapping fixes - fix confusing error message - protocol negotiation fixes, including NTLMSSP fix - two encryption fixes - directory listing fix - some cleanup fixes * tag '6.1-rc-ksmbd-fixes' of git://git.samba.org/ksmbd: (24 commits) ksmbd: validate share name from share config response ksmbd: call ib_drain_qp when disconnected ksmbd: make utf-8 file name comparison work in __caseless_lookup() ksmbd: Fix user namespace mapping ksmbd: hide socket error message when ipv6 config is disable ksmbd: reduce server smbdirect max send/receive segment sizes ksmbd: decrease the number of SMB3 smbdirect server SGEs ksmbd: Fix wrong return value and message length check in smb2_ioctl() ksmbd: set NTLMSSP_NEGOTIATE_SEAL flag to challenge blob ksmbd: fix encryption failure issue for session logoff response ksmbd: fix endless loop when encryption for response fails ksmbd: fill sids in SMB_FIND_FILE_POSIX_INFO response ksmbd: set file permission mode to match Samba server posix extension behavior ksmbd: change security id to the one samba used for posix extension ksmbd: update documentation ksmbd: casefold utf-8 share names and fix ascii lowercase conversion ksmbd: port to vfs{g,u}id_t and associated helpers ksmbd: fix incorrect handling of iterate_dir MAINTAINERS: remove Hyunchul Lee from ksmbd maintainers MAINTAINERS: Add Tom Talpey as ksmbd reviewer ...
2022-10-06Merge tag 'ext4_for_linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4 Pull ext4 updates from Ted Ts'o: "The first two changes involve files outside of fs/ext4: - submit_bh() can never return an error, so change it to return void, and remove the unused checks from its callers - fix I_DIRTY_TIME handling so it will be set even if the inode already has I_DIRTY_INODE Performance: - Always enable i_version counter (as btrfs and xfs already do). Remove some uneeded i_version bumps to avoid unnecessary nfs cache invalidations - Wake up journal waiters in FIFO order, to avoid some journal users from not getting a journal handle for an unfairly long time - In ext4_write_begin() allocate any necessary buffer heads before starting the journal handle - Don't try to prefetch the block allocation bitmaps for a read-only file system Bug Fixes: - Fix a number of fast commit bugs, including resources leaks and out of bound references in various error handling paths and/or if the fast commit log is corrupted - Avoid stopping the online resize early when expanding a file system which is less than 16TiB to a size greater than 16TiB - Fix apparent metadata corruption caused by a race with a metadata buffer head getting migrated while it was trying to be read - Mark the lazy initialization thread freezable to prevent suspend failures - Other miscellaneous bug fixes Cleanups: - Break up the incredibly long ext4_full_super() function by refactoring to move code into more understandable, smaller functions - Remove the deprecated (and ignored) noacl and nouser_attr mount option - Factor out some common code in fast commit handling - Other miscellaneous cleanups" * tag 'ext4_for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4: (53 commits) ext4: fix potential out of bound read in ext4_fc_replay_scan() ext4: factor out ext4_fc_get_tl() ext4: introduce EXT4_FC_TAG_BASE_LEN helper ext4: factor out ext4_free_ext_path() ext4: remove unnecessary drop path references in mext_check_coverage() ext4: update 'state->fc_regions_size' after successful memory allocation ext4: fix potential memory leak in ext4_fc_record_regions() ext4: fix potential memory leak in ext4_fc_record_modified_inode() ext4: remove redundant checking in ext4_ioctl_checkpoint jbd2: add miss release buffer head in fc_do_one_pass() ext4: move DIOREAD_NOLOCK setting to ext4_set_def_opts() ext4: remove useless local variable 'blocksize' ext4: unify the ext4 super block loading operation ext4: factor out ext4_journal_data_mode_check() ext4: factor out ext4_load_and_init_journal() ext4: factor out ext4_group_desc_init() and ext4_group_desc_free() ext4: factor out ext4_geometry_check() ext4: factor out ext4_check_feature_compatibility() ext4: factor out ext4_init_metadata_csum() ext4: factor out ext4_encoding_init() ...
2022-10-06Merge tag 'pull-file' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfsLinus Torvalds
Pull vfs file updates from Al Viro: "struct file-related stuff" * tag 'pull-file' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: dma_buf_getfile(): don't bother with ->f_flags reassignments Change calling conventions for filldir_t locks: fix TOCTOU race when granting write lease
2022-10-05ksmbd: update documentationNamjae Jeon
configuration.txt in ksmbd-tools moved to ksmbd.conf manpage. update it and more detailed ksmbd-tools build method. Signed-off-by: Namjae Jeon <linkinjeon@kernel.org> Reviewed-by: Sergey Senozhatsky <senozhatsky@chromium.org> Reviewed-by: Tom Talpey <tom@talpey.com> Signed-off-by: Steve French <stfrench@microsoft.com>
2022-10-04ceph: remove Sage's git tree from documentationTiezhu Yang
Sage's git tree has not been pushed to in years, and it was removed in commit 3a5ccecd9af7 ("MAINTAINERS: remove myself as ceph co-maintainer"), so it is better to remove it in the documentation too. Signed-off-by: Tiezhu Yang <yangtiezhu@loongson.cn> Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
2022-09-30docs: filesystems: sysfs: Make text and code for ->show() consistentAndy Shevchenko
The documentation says that ->show() should only use sysfs_emit() or sysfs_emit_at(), but example keeps outdated code. Update the code to be consistent. Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Link: https://lore.kernel.org/r/20220928135741.54919-1-andriy.shevchenko@linux.intel.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-09-29fs: record I_DIRTY_TIME even if inode already has I_DIRTY_INODELukas Czerner
Currently the I_DIRTY_TIME will never get set if the inode already has I_DIRTY_INODE with assumption that it supersedes I_DIRTY_TIME. That's true, however ext4 will only update the on-disk inode in ->dirty_inode(), not on actual writeback. As a result if the inode already has I_DIRTY_INODE state by the time we get to __mark_inode_dirty() only with I_DIRTY_TIME, the time was already filled into on-disk inode and will not get updated until the next I_DIRTY_INODE update, which might never come if we crash or get a power failure. The problem can be reproduced on ext4 by running xfstest generic/622 with -o iversion mount option. Fix it by allowing I_DIRTY_TIME to be set even if the inode already has I_DIRTY_INODE. Also make sure that the case is properly handled in writeback_single_inode() as well. Additionally changes in xfs_fs_dirty_inode() was made to accommodate for I_DIRTY_TIME in flag. Thanks Jan Kara for suggestions on how to make this work properly. Cc: Dave Chinner <david@fromorbit.com> Cc: Christoph Hellwig <hch@infradead.org> Cc: stable@kernel.org Signed-off-by: Lukas Czerner <lczerner@redhat.com> Suggested-by: Jan Kara <jack@suse.cz> Reviewed-by: Jan Kara <jack@suse.cz> Link: https://lore.kernel.org/r/20220825100657.44217-1-lczerner@redhat.com Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2022-09-27Documentation: spufs: correct a duplicate word typoRandy Dunlap
Fix a typo of "or" which should be "of". Signed-off-by: Randy Dunlap <rdunlap@infradead.org> Cc: Jeremy Kerr <jk@ozlabs.org> Cc: Arnd Bergmann <arnd@arndb.de> Cc: linuxppc-dev@lists.ozlabs.org Cc: Jonathan Corbet <corbet@lwn.net> Reviewed-by: Jeremy Kerr <jk@ozlabs.org> Link: https://lore.kernel.org/r/20220829232908.32437-1-rdunlap@infradead.org Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2022-09-27Documentation: filesystems: correct possessive "its"Randy Dunlap
Change occurrences of "it's" that are possessive to "its" so that they don't read as "it is". For f2fs.rst, reword one description for better clarity. Signed-off-by: Randy Dunlap <rdunlap@infradead.org> Cc: Jonathan Corbet <corbet@lwn.net> Cc: linux-fsdevel@vger.kernel.org Cc: linux-f2fs-devel@lists.sourceforge.net Cc: linux-xfs@vger.kernel.org Cc: Christian Brauner <brauner@kernel.org> Cc: Seth Forshee <sforshee@kernel.org> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Theodore Ts'o <tytso@mit.edu> Cc: Jaegeuk Kim <jaegeuk@kernel.org> Reviewed-by: Darrick J. Wong <djwong@kernel.org> Reviewed-by: "Christian Brauner (Microsoft)" <brauner@kernel.org> Reviewed-by: Chao Yu <chao@kernel.org> Reviewed-by: Jaegeuk Kim <jaegeuk@kernel.org> Link: https://lore.kernel.org/r/20220901002828.25102-1-rdunlap@infradead.org Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2022-09-27Remove duplicate words inside documentationAkhil Raj
I have removed repeated `the` inside the documentation Signed-off-by: Akhil Raj <lf32.dev@gmail.com> Link: https://lore.kernel.org/r/20220827145359.32599-1-lf32.dev@gmail.com Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2022-09-27Documentation: ext4: correct the document about superblockJunChao Sun
The description of s_lastcheck_hi, s_first_error_time_hi, and s_last_error_time_hi fields refer to themselves, while these means referring to upper 8 bits (byte) of corresponding fields (s_lastcheck, s_first_error_time, and s_last_error_time). Correct the mistake. Signed-off-by: JunChao Sun <sunjunchao2870@gmail.com> Reviewed-by: Darrick J. Wong <djwong@kernel.org> Link: https://lore.kernel.org/r/20220815125233.2040-1-sunjunchao2870@gmail.com Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2022-09-27Documentation: filesystems: xfs: update pseudocode and typo fixesZhao Mengmeng
According to the implementation of xfs_trans_roll(), it calls xfs_trans_reserve(), which reserves not only log space, but also free disk blocks. In short, the "transaction stuff". So change xfs_log_reserve() to xfs_trans_reserve(). Besides, fix several typo issues. Signed-off-by: Zhao Mengmeng <zhaomengmeng@kylinos.cn> Reviewed-by: Darrick J. Wong <djwong@kernel.org> Link: https://lore.kernel.org/r/20220823013653.203469-1-zhaomzhao@126.com Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2022-09-24vfs: open inside ->tmpfile()Miklos Szeredi
This is in preparation for adding tmpfile support to fuse, which requires that the tmpfile creation and opening are done as a single operation. Replace the 'struct dentry *' argument of i_op->tmpfile with 'struct file *'. Call finish_open_simple() as the last thing in ->tmpfile() instances (may be omitted in the error case). Change d_tmpfile() argument to 'struct file *' as well to make callers more readable. Reviewed-by: Christian Brauner (Microsoft) <brauner@kernel.org> Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
2022-08-24mm: add NR_SECONDARY_PAGETABLE to count secondary page table uses.Yosry Ahmed
We keep track of several kernel memory stats (total kernel memory, page tables, stack, vmalloc, etc) on multiple levels (global, per-node, per-memcg, etc). These stats give insights to users to how much memory is used by the kernel and for what purposes. Currently, memory used by KVM mmu is not accounted in any of those kernel memory stats. This patch series accounts the memory pages used by KVM for page tables in those stats in a new NR_SECONDARY_PAGETABLE stat. This stat can be later extended to account for other types of secondary pages tables (e.g. iommu page tables). KVM has a decent number of large allocations that aren't for page tables, but for most of them, the number/size of those allocations scales linearly with either the number of vCPUs or the amount of memory assigned to the VM. KVM's secondary page table allocations do not scale linearly, especially when nested virtualization is in use. From a KVM perspective, NR_SECONDARY_PAGETABLE will scale with KVM's per-VM pages_{4k,2m,1g} stats unless the guest is doing something bizarre (e.g. accessing only 4kb chunks of 2mb pages so that KVM is forced to allocate a large number of page tables even though the guest isn't accessing that much memory). However, someone would need to either understand how KVM works to make that connection, or know (or be told) to go look at KVM's stats if they're running VMs to better decipher the stats. Furthermore, having NR_PAGETABLE side-by-side with NR_SECONDARY_PAGETABLE is informative. For example, when backing a VM with THP vs. HugeTLB, NR_SECONDARY_PAGETABLE is roughly the same, but NR_PAGETABLE is an order of magnitude higher with THP. So having this stat will at the very least prove to be useful for understanding tradeoffs between VM backing types, and likely even steer folks towards potential optimizations. The original discussion with more details about the rationale: https://lore.kernel.org/all/87ilqoi77b.wl-maz@kernel.org This stat will be used by subsequent patches to count KVM mmu memory usage. Signed-off-by: Yosry Ahmed <yosryahmed@google.com> Acked-by: Shakeel Butt <shakeelb@google.com> Acked-by: Marc Zyngier <maz@kernel.org> Link: https://lore.kernel.org/r/20220823004639.2387269-2-yosryahmed@google.com Signed-off-by: Sean Christopherson <seanjc@google.com>
2022-08-17Change calling conventions for filldir_tAl Viro
filldir_t instances (directory iterators callbacks) used to return 0 for "OK, keep going" or -E... for "stop". Note that it's *NOT* how the error values are reported - the rules for those are callback-dependent and ->iterate{,_shared}() instances only care about zero vs. non-zero (look at emit_dir() and friends). So let's just return bool ("should we keep going?") - it's less confusing that way. The choice between "true means keep going" and "true means stop" is bikesheddable; we have two groups of callbacks - do something for everything in directory, until we run into problem and find an entry in directory and do something to it. The former tended to use 0/-E... conventions - -E<something> on failure. The latter tended to use 0/1, 1 being "stop, we are done". The callers treated anything non-zero as "stop", ignoring which non-zero value did they get. "true means stop" would be more natural for the second group; "true means keep going" - for the first one. I tried both variants and the things like if allocation failed something = -ENOMEM; return true; just looked unnatural and asking for trouble. [folded suggestion from Matthew Wilcox <willy@infradead.org>] Acked-by: Christian Brauner (Microsoft) <brauner@kernel.org> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2022-08-08Merge tag 'f2fs-for-6.0' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/jaegeuk/f2fs Pull f2fs updates from Jaegeuk Kim: "In this cycle, we mainly fixed some corner cases that manipulate a per-file compression flag inappropriately. And, we found f2fs counted valid blocks in a section incorrectly when zone capacity is set, and thus, fixed it with additional sysfs entry to check it easily. Lastly, this series includes several patches with respect to the new atomic write support such as a couple of bug fixes and re-adding atomic_write_abort support that we removed by mistake in the previous release. Enhancements: - add sysfs entries to understand atomic write operations and zone capacity - introduce memory mode to get a hint for low-memory devices - adjust the waiting time of foreground GC - decompress clusters under softirq to avoid non-deterministic latency - do not skip updating inode when retrying to flush node page - enforce single zone capacity Bug fixes: - set the compression/no-compression flags correctly - revive F2FS_IOC_ABORT_VOLATILE_WRITE - check inline_data during compressed inode conversion - understand zone capacity when calculating valid block count As usual, the series includes several minor clean-ups and sanity checks" * tag 'f2fs-for-6.0' of git://git.kernel.org/pub/scm/linux/kernel/git/jaegeuk/f2fs: (29 commits) f2fs: use onstack pages instead of pvec f2fs: intorduce f2fs_all_cluster_page_ready f2fs: clean up f2fs_abort_atomic_write() f2fs: handle decompress only post processing in softirq f2fs: do not allow to decompress files have FI_COMPRESS_RELEASED f2fs: do not set compression bit if kernel doesn't support f2fs: remove device type check for direct IO f2fs: fix null-ptr-deref in f2fs_get_dnode_of_data f2fs: revive F2FS_IOC_ABORT_VOLATILE_WRITE f2fs: fix to do sanity check on segment type in build_sit_entries() f2fs: obsolete unused MAX_DISCARD_BLOCKS f2fs: fix to avoid use f2fs_bug_on() in f2fs_new_node_page() f2fs: fix to remove F2FS_COMPR_FL and tag F2FS_NOCOMP_FL at the same time f2fs: introduce sysfs atomic write statistics f2fs: don't bother wait_ms by foreground gc f2fs: invalidate meta pages only for post_read required inode f2fs: allow compression of files without blocks f2fs: fix to check inline_data during compressed inode conversion f2fs: Delete f2fs_copy_page() and replace with memcpy_page() f2fs: fix to invalidate META_MAPPING before DIO write ...
2022-08-08Merge tag 'fuse-update-6.0' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/mszeredi/fuse Pull fuse updates from Miklos Szeredi: - Fix an issue with reusing the bdi in case of block based filesystems - Allow root (in init namespace) to access fuse filesystems in user namespaces if expicitly enabled with a module param - Misc fixes * tag 'fuse-update-6.0' of git://git.kernel.org/pub/scm/linux/kernel/git/mszeredi/fuse: fuse: retire block-device-based superblock on force unmount vfs: function to prevent re-use of block-device-based superblocks virtio_fs: Modify format for virtio_fs_direct_access virtiofs: delete unused parameter for virtio_fs_cleanup_vqs fuse: Add module param for CAP_SYS_ADMIN access bypassing allow_other fuse: Remove the control interface for virtio-fs fuse: ioctl: translate ENOSYS fuse: limit nsec fuse: avoid unnecessary spinlock bump fuse: fix deadlock between atomic O_TRUNC and page invalidation fuse: write inode in fuse_release()
2022-08-05Merge tag 'mm-stable-2022-08-03' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm Pull MM updates from Andrew Morton: "Most of the MM queue. A few things are still pending. Liam's maple tree rework didn't make it. This has resulted in a few other minor patch series being held over for next time. Multi-gen LRU still isn't merged as we were waiting for mapletree to stabilize. The current plan is to merge MGLRU into -mm soon and to later reintroduce mapletree, with a view to hopefully getting both into 6.1-rc1. Summary: - The usual batches of cleanups from Baoquan He, Muchun Song, Miaohe Lin, Yang Shi, Anshuman Khandual and Mike Rapoport - Some kmemleak fixes from Patrick Wang and Waiman Long - DAMON updates from SeongJae Park - memcg debug/visibility work from Roman Gushchin - vmalloc speedup from Uladzislau Rezki - more folio conversion work from Matthew Wilcox - enhancements for coherent device memory mapping from Alex Sierra - addition of shared pages tracking and CoW support for fsdax, from Shiyang Ruan - hugetlb optimizations from Mike Kravetz - Mel Gorman has contributed some pagealloc changes to improve latency and realtime behaviour. - mprotect soft-dirty checking has been improved by Peter Xu - Many other singleton patches all over the place" [ XFS merge from hell as per Darrick Wong in https://lore.kernel.org/all/YshKnxb4VwXycPO8@magnolia/ ] * tag 'mm-stable-2022-08-03' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (282 commits) tools/testing/selftests/vm/hmm-tests.c: fix build mm: Kconfig: fix typo mm: memory-failure: convert to pr_fmt() mm: use is_zone_movable_page() helper hugetlbfs: fix inaccurate comment in hugetlbfs_statfs() hugetlbfs: cleanup some comments in inode.c hugetlbfs: remove unneeded header file hugetlbfs: remove unneeded hugetlbfs_ops forward declaration hugetlbfs: use helper macro SZ_1{K,M} mm: cleanup is_highmem() mm/hmm: add a test for cross device private faults selftests: add soft-dirty into run_vmtests.sh selftests: soft-dirty: add test for mprotect mm/mprotect: fix soft-dirty check in can_change_pte_writable() mm: memcontrol: fix potential oom_lock recursion deadlock mm/gup.c: fix formatting in check_and_migrate_movable_page() xfs: fail dax mount if reflink is enabled on a partition mm/memcontrol.c: remove the redundant updating of stats_flush_threshold userfaultfd: don't fail on unrecognized features hugetlb_cgroup: fix wrong hugetlb cgroup numa stat ...
2022-08-04Merge tag 'xfs-5.20-merge-6' of git://git.kernel.org/pub/scm/fs/xfs/xfs-linuxLinus Torvalds
Pull xfs updates from Darrick Wong: "The biggest changes for this release are the log scalability improvements, lockless lookups for the buffer cache, and making the attr fork a permanent part of the incore inode in preparation for directory parent pointers. There's also a bunch of bug fixes that have accumulated since -rc5. I might send you a second pull request with some more bug fixes that I'm still working on. Once the merge window ends, I will hand maintainership back to Dave Chinner until the 6.1-rc1 release so that I can conduct the design review for the online fsck feature, and try to get it merged. Summary: - Improve scalability of the XFS log by removing spinlocks and global synchronization points. - Add security labels to whiteout inodes to match the other filesystems. - Clean up per-ag pointer passing to simplify call sites. - Reduce verifier overhead by precalculating more AG geometry. - Implement fast-path lockless lookups in the buffer cache to reduce spinlock hammering. - Make attr forks a permanent part of the inode structure to fix a UAF bug and because most files these days tend to have security labels and soon will have parent pointers too. - Clean up XFS_IFORK_Q usage and give it a better name. - Fix more UAF bugs in the xattr code. - SOB my tags. - Fix some typos in the timestamp range documentation. - Fix a few more memory leaks. - Code cleanups and typo fixes. - Fix an unlocked inode fork pointer access in getbmap" * tag 'xfs-5.20-merge-6' of git://git.kernel.org/pub/scm/fs/xfs/xfs-linux: (61 commits) xfs: delete extra space and tab in blank line xfs: fix NULL pointer dereference in xfs_getbmap() xfs: Fix typo 'the the' in comment xfs: Fix comment typo xfs: don't leak memory when attr fork loading fails xfs: fix for variable set but not used warning xfs: xfs_buf cache destroy isn't RCU safe xfs: delete unnecessary NULL checks xfs: fix comment for start time value of inode with bigtime enabled xfs: fix use-after-free in xattr node block inactivation xfs: lockless buffer lookup xfs: remove a superflous hash lookup when inserting new buffers xfs: reduce the number of atomic when locking a buffer after lookup xfs: merge xfs_buf_find() and xfs_buf_get_map() xfs: break up xfs_buf_find() into individual pieces xfs: add in-memory iunlink log item xfs: add log item precommit operation xfs: combine iunlink inode update functions xfs: clean up xfs_iunlink_update_inode() xfs: double link the unlinked inode list ...
2022-08-04Merge tag 'ext4_for_linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4 Pull ext4 updates from Ted Ts'o: "Add new ioctls to set and get the file system UUID in the ext4 superblock and improved the performance of the online resizing of file systems with bigalloc enabled. Fixed a lot of bugs, in particular for the inline data feature, potential races when creating and deleting inodes with shared extended attribute blocks, and the handling of directory blocks which are corrupted" * tag 'ext4_for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4: (37 commits) ext4: add ioctls to get/set the ext4 superblock uuid ext4: avoid resizing to a partial cluster size ext4: reduce computation of overhead during resize jbd2: fix assertion 'jh->b_frozen_data == NULL' failure when journal aborted ext4: block range must be validated before use in ext4_mb_clear_bb() mbcache: automatically delete entries from cache on freeing mbcache: Remove mb_cache_entry_delete() ext2: avoid deleting xattr block that is being reused ext2: unindent codeblock in ext2_xattr_set() ext2: factor our freeing of xattr block reference ext4: fix race when reusing xattr blocks ext4: unindent codeblock in ext4_xattr_block_set() ext4: remove EA inode entry from mbcache on inode eviction mbcache: add functions to delete entry if unused mbcache: don't reclaim used entries ext4: make sure ext4_append() always allocates new block ext4: check if directory block is within i_size ext4: reflect mb_optimize_scan value in options file ext4: avoid remove directory when directory is corrupted ext4: aligned '*' in comments ...
2022-08-03Merge tag 'pull-work.lseek' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs Pull vfs lseek updates from Al Viro: "Jason's lseek series. Saner handling of 'lseek should fail with ESPIPE' - this gets rid of the magical no_llseek thing and makes checks consistent. In particular, the ad-hoc "can we do splice via internal pipe" checks got saner (and somewhat more permissive, which is what Jason had been after, AFAICT)" * tag 'pull-work.lseek' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: fs: remove no_llseek fs: check FMODE_LSEEK to control internal pipe splicing vfio: do not set FMODE_LSEEK flag dma-buf: remove useless FMODE_LSEEK flag fs: do not compare against ->llseek fs: clear or set FMODE_LSEEK based on llseek function
2022-08-03Merge tag 'folio-6.0' of git://git.infradead.org/users/willy/pagecacheLinus Torvalds
Pull folio updates from Matthew Wilcox: - Fix an accounting bug that made NR_FILE_DIRTY grow without limit when running xfstests - Convert more of mpage to use folios - Remove add_to_page_cache() and add_to_page_cache_locked() - Convert find_get_pages_range() to filemap_get_folios() - Improvements to the read_cache_page() family of functions - Remove a few unnecessary checks of PageError - Some straightforward filesystem conversions to use folios - Split PageMovable users out from address_space_operations into their own movable_operations - Convert aops->migratepage to aops->migrate_folio - Remove nobh support (Christoph Hellwig) * tag 'folio-6.0' of git://git.infradead.org/users/willy/pagecache: (78 commits) fs: remove the NULL get_block case in mpage_writepages fs: don't call ->writepage from __mpage_writepage fs: remove the nobh helpers jfs: stop using the nobh helper ext2: remove nobh support ntfs3: refactor ntfs_writepages mm/folio-compat: Remove migration compatibility functions fs: Remove aops->migratepage() secretmem: Convert to migrate_folio hugetlb: Convert to migrate_folio aio: Convert to migrate_folio f2fs: Convert to filemap_migrate_folio() ubifs: Convert to filemap_migrate_folio() btrfs: Convert btrfs_migratepage to migrate_folio mm/migrate: Add filemap_migrate_folio() mm/migrate: Convert migrate_page() to migrate_folio() nfs: Convert to migrate_folio btrfs: Convert btree_migratepage to migrate_folio mm/migrate: Convert expected_page_refs() to folio_expected_refs() mm/migrate: Convert buffer_migrate_page() to buffer_migrate_folio() ...
2022-08-02Documentation: ext4: fix cell spacing of table heading on blockmap tableBagas Sanjaya
Commit 3103084afcf234 ("ext4, doc: remove unnecessary escaping") removes redundant underscore escaping, however the cell spacing in heading row of blockmap table became not aligned anymore, hence triggers malformed table warning: Documentation/filesystems/ext4/blockmap.rst:3: WARNING: Malformed table. +---------------------+------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+ | i.i_block Offset | Where It Points | <snipped>... The warning caused the table not being loaded. Realign the heading row cell by adding missing space at the first cell to fix the warning. Fixes: 3103084afcf234 ("ext4, doc: remove unnecessary escaping") Cc: stable@kernel.org Cc: Andreas Dilger <adilger.kernel@dilger.ca> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Wang Jianjian <wangjianjian3@huawei.com> Cc: linux-ext4@vger.kernel.org Cc: linux-kernel@vger.kernel.org Signed-off-by: Bagas Sanjaya <bagasdotme@gmail.com> Link: https://lore.kernel.org/r/20220619072938.7334-1-bagasdotme@gmail.com Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2022-08-02Merge tag 'docs-6.0' of git://git.lwn.net/linuxLinus Torvalds
Pull documentation updates from Jonathan Corbet: "This was a moderately busy cycle for documentation, but nothing all that earth-shaking: - More Chinese translations, and an update to the Italian translations. The Japanese, Korean, and traditional Chinese translations are more-or-less unmaintained at this point, instead. - Some build-system performance improvements. - The removal of the archaic submitting-drivers.rst document, with the movement of what useful material that remained into other docs. - Improvements to sphinx-pre-install to, hopefully, give more useful suggestions. - A number of build-warning fixes Plus the usual collection of typo fixes, updates, and more" * tag 'docs-6.0' of git://git.lwn.net/linux: (92 commits) docs: efi-stub: Fix paths for x86 / arm stubs Docs/zh_CN: Update the translation of sched-stats to 5.19-rc8 Docs/zh_CN: Update the translation of pci to 5.19-rc8 Docs/zh_CN: Update the translation of pci-iov-howto to 5.19-rc8 Docs/zh_CN: Update the translation of usage to 5.19-rc8 Docs/zh_CN: Update the translation of testing-overview to 5.19-rc8 Docs/zh_CN: Update the translation of sparse to 5.19-rc8 Docs/zh_CN: Update the translation of kasan to 5.19-rc8 Docs/zh_CN: Update the translation of iio_configfs to 5.19-rc8 doc:it_IT: align Italian documentation docs: Remove spurious tag from admin-guide/mm/overcommit-accounting.rst Documentation: process: Update email client instructions for Thunderbird docs: ABI: correct QEMU fw_cfg spec path doc/zh_CN: remove submitting-driver reference from docs docs: zh_TW: align to submitting-drivers removal docs: zh_CN: align to submitting-drivers removal docs: ko_KR: howto: remove reference to removed submitting-drivers docs: ja_JP: howto: remove reference to removed submitting-drivers docs: it_IT: align to submitting-drivers removal docs: process: remove outdated submitting-drivers.rst ...
2022-08-02Merge tag 'v5.20-p1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6 Pull crypto updates from Herbert Xu: "API: - Make proc files report fips module name and version Algorithms: - Move generic SHA1 code into lib/crypto - Implement Chinese Remainder Theorem for RSA - Remove blake2s - Add XCTR with x86/arm64 acceleration - Add POLYVAL with x86/arm64 acceleration - Add HCTR2 - Add ARIA Drivers: - Add support for new CCP/PSP device ID in ccp" * tag 'v5.20-p1' of git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6: (89 commits) crypto: tcrypt - Remove the static variable initialisations to NULL crypto: arm64/poly1305 - fix a read out-of-bound crypto: hisilicon/zip - Use the bitmap API to allocate bitmaps crypto: hisilicon/sec - fix auth key size error crypto: ccree - Remove a useless dma_supported() call crypto: ccp - Add support for new CCP/PSP device ID crypto: inside-secure - Add missing MODULE_DEVICE_TABLE for of crypto: hisilicon/hpre - don't use GFP_KERNEL to alloc mem during softirq crypto: testmgr - some more fixes to RSA test vectors cyrpto: powerpc/aes - delete the rebundant word "block" in comments hwrng: via - Fix comment typo crypto: twofish - Fix comment typo crypto: rmd160 - fix Kconfig "its" grammar crypto: keembay-ocs-ecc - Drop if with an always false condition Documentation: qat: rewrite description Documentation: qat: Use code block for qat sysfs example crypto: lib - add module license to libsha1 crypto: lib - make the sha1 library optional crypto: lib - move lib/sha1.c into lib/crypto/ crypto: fips - make proc files report fips module name and version ...
2022-08-02Merge tag 'fsverity-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/fs/fscrypt/fscrypt Pull fsverity update from Eric Biggers: "Just a small documentation update to mention the btrfs support" * tag 'fsverity-for-linus' of git://git.kernel.org/pub/scm/fs/fscrypt/fscrypt: fs-verity: mention btrfs support
2022-08-02ext2: remove nobh supportChristoph Hellwig
The nobh mode is an obscure feature to save lowlevel for large memory 32-bit configurations while trading for much slower performance and has been long obsolete. Remove it. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Jan Kara <jack@suse.cz> Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
2022-08-02fs: Add aops->migrate_folioMatthew Wilcox (Oracle)
Provide a folio-based replacement for aops->migratepage. Update the documentation to document migrate_folio instead of migratepage. Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org> Reviewed-by: Christoph Hellwig <hch@lst.de>
2022-08-02mm: Convert all PageMovable users to movable_operationsMatthew Wilcox (Oracle)
These drivers are rather uncomfortably hammered into the address_space_operations hole. They aren't filesystems and don't behave like filesystems. They just need their own movable_operations structure, which we can point to directly from page->mapping. Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
2022-08-01Merge tag 'fs.idmapped.overlay.acl.v5.20' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/brauner/linux Pull acl updates from Christian Brauner: "Last cycle we introduced support for mounting overlayfs on top of idmapped mounts. While looking into additional testing we realized that posix acls don't really work correctly with stacking filesystems on top of idmapped layers. We already knew what the fix were but it would require work that is more suitable for the merge window so we turned off posix acls for v5.19 for overlayfs on top of idmapped layers with Miklos routing my patch upstream in 72a8e05d4f66 ("Merge tag 'ovl-fixes-5.19-rc7' [..]"). This contains the work to support posix acls for overlayfs on top of idmapped layers. Since the posix acl fixes should use the new vfs{g,u}id_t work the associated branch has been merged in. (We sent a pull request for this earlier.) We've also pulled in Miklos pull request containing my patch to turn of posix acls on top of idmapped layers. This allowed us to avoid rebasing the branch which we didn't like because we were already at rc7 by then. Merging it in allows this branch to first fix posix acls and then to cleanly revert the temporary fix it brought in by commit 4a47c6385bb4 ("ovl: turn of SB_POSIXACL with idmapped layers temporarily"). The last patch in this series adds Seth Forshee as a co-maintainer for idmapped mounts. Seth has been integral to all of this work and is also the main architect behind the filesystem idmapping work which ultimately made filesystems such as FUSE and overlayfs available in containers. He continues to be active in both development and review. I'm very happy he decided to help and he has my full trust. This increases the bus factor which is always great for work like this. I'm honestly very excited about this because I think in general we don't do great in the bringing on new maintainers department" For more explanations of the ACL issues, see https://lore.kernel.org/all/20220801145520.1532837-1-brauner@kernel.org/ * tag 'fs.idmapped.overlay.acl.v5.20' of git://git.kernel.org/pub/scm/linux/kernel/git/brauner/linux: Add Seth Forshee as co-maintainer for idmapped mounts Revert "ovl: turn of SB_POSIXACL with idmapped layers temporarily" ovl: handle idmappings in ovl_get_acl() acl: make posix_acl_clone() available to overlayfs acl: port to vfs{g,u}id_t acl: move idmapped mount fixup into vfs_{g,s}etxattr() mnt_idmapping: add vfs[g,u]id_into_k[g,u]id()
2022-07-30f2fs: introduce memory modeDaeho Jeong
Introduce memory mode to supports "normal" and "low" memory modes. "low" mode is to support low memory devices. Because of the nature of low memory devices, in this mode, f2fs will try to save memory sometimes by sacrificing performance. "normal" mode is the default mode and same as before. Signed-off-by: Daeho Jeong <daehojeong@google.com> Reviewed-by: Chao Yu <chao@kernel.org> Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2022-07-21fuse: Add module param for CAP_SYS_ADMIN access bypassing allow_otherDave Marchevsky
Since commit 73f03c2b4b52 ("fuse: Restrict allow_other to the superblock's namespace or a descendant"), access to allow_other FUSE filesystems has been limited to users in the mounting user namespace or descendants. This prevents a process that is privileged in its userns - but not its parent namespaces - from mounting a FUSE fs w/ allow_other that is accessible to processes in parent namespaces. While this restriction makes sense overall it breaks a legitimate usecase: I have a tracing daemon which needs to peek into process' open files in order to symbolicate - similar to 'perf'. The daemon is a privileged process in the root userns, but is unable to peek into FUSE filesystems mounted by processes in child namespaces. This patch adds a module param, allow_sys_admin_access, to act as an escape hatch for this descendant userns logic and for the allow_other mount option in general. Setting allow_sys_admin_access allows processes with CAP_SYS_ADMIN in the initial userns to access FUSE filesystems irrespective of the mounting userns or whether allow_other was set. A sysadmin setting this param must trust FUSEs on the host to not DoS processes as described in 73f03c2b4b52. Signed-off-by: Dave Marchevsky <davemarchevsky@fb.com> Reviewed-by: Christian Brauner (Microsoft) <brauner@kernel.org> Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
2022-07-17doc: proc: fix the description to THPeligibleYang Shi
The THPeligible bit shows 1 if and only if the VMA is eligible for allocating THP and the THP is also PMD mappable. Some misaligned file VMAs may be eligible for allocating THP but the THP can't be mapped by PMD. Make this more explicitly to avoid ambiguity. Link: https://lkml.kernel.org/r/20220616174840.1202070-8-shy828301@gmail.com Signed-off-by: Yang Shi <shy828301@gmail.com> Reviewed-by: Zach O'Keefe <zokeefe@google.com> Cc: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Cc: Matthew Wilcox <willy@infradead.org> Cc: Miaohe Lin <linmiaohe@huawei.com> Cc: Vlastimil Babka <vbabka@suse.cz> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2022-07-16fs: remove no_llseekJason A. Donenfeld
Now that all callers of ->llseek are going through vfs_llseek(), we don't gain anything by keeping no_llseek around. Nothing actually calls it and setting ->llseek to no_lseek is completely equivalent to leaving it NULL. Longer term (== by the end of merge window) we want to remove all such intializations. To simplify the merge window this commit does *not* touch initializers - it only defines no_llseek as NULL (and simplifies the tests on file opening). At -rc1 we'll need do a mechanical removal of no_llseek - git grep -l -w no_llseek | grep -v porting.rst | while read i; do sed -i '/\<no_llseek\>/d' $i done would do it. Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2022-07-15fs-verity: mention btrfs supportEric Biggers
btrfs supports fs-verity since Linux v5.15. Document this. Signed-off-by: Eric Biggers <ebiggers@google.com> Acked-by: David Sterba <dsterba@suse.com> Link: https://lore.kernel.org/r/20220610000616.18225-1-ebiggers@kernel.org
2022-07-15Revert "ovl: turn of SB_POSIXACL with idmapped layers temporarily"Christian Brauner
This reverts commit 4a47c6385bb4e0786826e75bd4555aba32953653. Now that we have a proper fix for POSIX ACLs with overlayfs on top of idmapped layers revert the temporary fix. Signed-off-by: Christian Brauner (Microsoft) <brauner@kernel.org>
2022-07-15Merge tag 'ceph-for-5.19-rc7' of https://github.com/ceph/ceph-clientLinus Torvalds
Pull ceph fix from Ilya Dryomov: "A folio locking fixup that Xiubo and David cooperated on, marked for stable. Most of it is in netfs but I picked it up into ceph tree on agreement with David" * tag 'ceph-for-5.19-rc7' of https://github.com/ceph/ceph-client: netfs: do not unlock and put the folio twice
2022-07-14netfs: do not unlock and put the folio twiceXiubo Li
check_write_begin() will unlock and put the folio when return non-zero. So we should avoid unlocking and putting it twice in netfs layer. Change the way ->check_write_begin() works in the following two ways: (1) Pass it a pointer to the folio pointer, allowing it to unlock and put the folio prior to doing the stuff it wants to do, provided it clears the folio pointer. (2) Change the return values such that 0 with folio pointer set means continue, 0 with folio pointer cleared means re-get and all error codes indicating an error (no special treatment for -EAGAIN). [ bagasdotme: use Sphinx code text syntax for *foliop pointer ] Cc: stable@vger.kernel.org Link: https://tracker.ceph.com/issues/56423 Link: https://lore.kernel.org/r/cf169f43-8ee7-8697-25da-0204d1b4343e@redhat.com Co-developed-by: David Howells <dhowells@redhat.com> Signed-off-by: Xiubo Li <xiubli@redhat.com> Signed-off-by: David Howells <dhowells@redhat.com> Signed-off-by: Bagas Sanjaya <bagasdotme@gmail.com> Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
2022-07-09Merge tag 'xfs-cil-scale-5.20' of ↵Darrick J. Wong
git://git.kernel.org/pub/scm/linux/kernel/git/dgc/linux-xfs into xfs-5.20-mergeA xfs: improve CIL scalability This series aims to improve the scalability of XFS transaction commits on large CPU count machines. My 32p machine hits contention limits in xlog_cil_commit() at about 700,000 transaction commits a section. It hits this at 16 thread workloads, and 32 thread workloads go no faster and just burn CPU on the CIL spinlocks. This patchset gets rid of spinlocks and global serialisation points in the xlog_cil_commit() path. It does this by moving to a combination of per-cpu counters, unordered per-cpu lists and post-ordered per-cpu lists. This results in transaction commit rates exceeding 1.4 million commits/s under unlink certain workloads, and while the log lock contention is largely gone there is still significant lock contention in the VFS (dentry cache, inode cache and security layers) at >600,000 transactions/s that still limit scalability. The changes to the CIL accounting and behaviour, combined with the structural changes to xlog_write() in prior patchsets make the per-cpu restructuring possible and sane. This allows us to move to precalculated reservation requirements that allow for reservation stealing to be accounted across multiple CPUs accurately. That is, instead of trying to account for continuation log opheaders on a "growth" basis, we pre-calculate how many iclogs we'll need to write out a maximally sized CIL checkpoint and steal that reserveD that space one commit at a time until the CIL has a full reservation. If we ever run a commit when we are already at the hard limit (because post-throttling) we simply take an extra reservation from each commit that is run when over the limit. Hence we don't need to do space usage math in the fast path and so never need to sum the per-cpu counters in this fast path. Similarly, per-cpu lists have the problem of ordering - we can't remove an item from a per-cpu list if we want to move it forward in the CIL. We solve this problem by using an atomic counter to give every commit a sequence number that is copied into the log items in that transaction. Hence relogging items just overwrites the sequence number in the log item, and does not move it in the per-cpu lists. Once we reaggregate the per-cpu lists back into a single list in the CIL push work, we can run it through list-sort() and reorder it back into a globally ordered list. This costs a bit of CPU time, but now that the CIL can run multiple works and pipelines properly, this is not a limiting factor for performance. It does increase fsync latency when the CIL is full, but workloads issuing large numbers of fsync()s or sync transactions end up with very small CILs and so the latency impact or sorting is not measurable for such workloads. OVerall, this pushes the transaction commit bottleneck out to the lockless reservation grant head updates. These atomic updates don't start to be a limiting fact until > 1.5 million transactions/s are being run, at which point the accounting functions start to show up in profiles as the highest CPU users. Still, this series doubles transaction throughput without increasing CPU usage before we get to that cacheline contention breakdown point... ` Signed-off-by: Dave Chinner <dchinner@redhat.com> Signed-off-by: Darrick J. Wong <djwong@kernel.org> * tag 'xfs-cil-scale-5.20' of git://git.kernel.org/pub/scm/linux/kernel/git/dgc/linux-xfs: xfs: expanding delayed logging design with background material xfs: xlog_sync() manually adjusts grant head space xfs: avoid cil push lock if possible xfs: move CIL ordering to the logvec chain xfs: convert log vector chain to use list heads xfs: convert CIL to unordered per cpu lists xfs: Add order IDs to log items in CIL xfs: convert CIL busy extents to per-cpu xfs: track CIL ticket reservation in percpu structure xfs: implement percpu cil space used calculation xfs: introduce per-cpu CIL tracking structure xfs: rework per-iclog header CIL reservation xfs: lift init CIL reservation out of xc_cil_lock xfs: use the CIL space used counter for emptiness checks
2022-07-08ovl: turn of SB_POSIXACL with idmapped layers temporarilyChristian Brauner
This cycle we added support for mounting overlayfs on top of idmapped mounts. Recently I've started looking into potential corner cases when trying to add additional tests and I noticed that reporting for POSIX ACLs is currently wrong when using idmapped layers with overlayfs mounted on top of it. I have sent out an patch that fixes this and makes POSIX ACLs work correctly but the patch is a bit bigger and we're already at -rc5 so I recommend we simply don't raise SB_POSIXACL when idmapped layers are used. Then we can fix the VFS part described below for the next merge window so we can have good exposure in -next. I'm going to give a rather detailed explanation to both the origin of the problem and mention the solution so people know what's going on. Let's assume the user creates the following directory layout and they have a rootfs /var/lib/lxc/c1/rootfs. The files in this rootfs are owned as you would expect files on your host system to be owned. For example, ~/.bashrc for your regular user would be owned by 1000:1000 and /root/.bashrc would be owned by 0:0. IOW, this is just regular boring filesystem tree on an ext4 or xfs filesystem. The user chooses to set POSIX ACLs using the setfacl binary granting the user with uid 4 read, write, and execute permissions for their .bashrc file: setfacl -m u:4:rwx /var/lib/lxc/c2/rootfs/home/ubuntu/.bashrc Now they to expose the whole rootfs to a container using an idmapped mount. So they first create: mkdir -pv /vol/contpool/{ctrover,merge,lowermap,overmap} mkdir -pv /vol/contpool/ctrover/{over,work} chown 10000000:10000000 /vol/contpool/ctrover/{over,work} The user now creates an idmapped mount for the rootfs: mount-idmapped/mount-idmapped --map-mount=b:0:10000000:65536 \ /var/lib/lxc/c2/rootfs \ /vol/contpool/lowermap This for example makes it so that /var/lib/lxc/c2/rootfs/home/ubuntu/.bashrc which is owned by uid and gid 1000 as being owned by uid and gid 10001000 at /vol/contpool/lowermap/home/ubuntu/.bashrc. Assume the user wants to expose these idmapped mounts through an overlayfs mount to a container. mount -t overlay overlay \ -o lowerdir=/vol/contpool/lowermap, \ upperdir=/vol/contpool/overmap/over, \ workdir=/vol/contpool/overmap/work \ /vol/contpool/merge The user can do this in two ways: (1) Mount overlayfs in the initial user namespace and expose it to the container. (2) Mount overlayfs on top of the idmapped mounts inside of the container's user namespace. Let's assume the user chooses the (1) option and mounts overlayfs on the host and then changes into a container which uses the idmapping 0:10000000:65536 which is the same used for the two idmapped mounts. Now the user tries to retrieve the POSIX ACLs using the getfacl command getfacl -n /vol/contpool/lowermap/home/ubuntu/.bashrc and to their surprise they see: # file: vol/contpool/merge/home/ubuntu/.bashrc # owner: 1000 # group: 1000 user::rw- user:4294967295:rwx group::r-- mask::rwx other::r-- indicating the uid wasn't correctly translated according to the idmapped mount. The problem is how we currently translate POSIX ACLs. Let's inspect the callchain in this example: idmapped mount /vol/contpool/merge: 0:10000000:65536 caller's idmapping: 0:10000000:65536 overlayfs idmapping (ofs->creator_cred): 0:0:4k /* initial idmapping */ sys_getxattr() -> path_getxattr() -> getxattr() -> do_getxattr() |> vfs_getxattr() | -> __vfs_getxattr() | -> handler->get == ovl_posix_acl_xattr_get() | -> ovl_xattr_get() | -> vfs_getxattr() | -> __vfs_getxattr() | -> handler->get() /* lower filesystem callback */ |> posix_acl_fix_xattr_to_user() { 4 = make_kuid(&init_user_ns, 4); 4 = mapped_kuid_fs(&init_user_ns /* no idmapped mount */, 4); /* FAILURE */ -1 = from_kuid(0:10000000:65536 /* caller's idmapping */, 4); } If the user chooses to use option (2) and mounts overlayfs on top of idmapped mounts inside the container things don't look that much better: idmapped mount /vol/contpool/merge: 0:10000000:65536 caller's idmapping: 0:10000000:65536 overlayfs idmapping (ofs->creator_cred): 0:10000000:65536 sys_getxattr() -> path_getxattr() -> getxattr() -> do_getxattr() |> vfs_getxattr() | -> __vfs_getxattr() | -> handler->get == ovl_posix_acl_xattr_get() | -> ovl_xattr_get() | -> vfs_getxattr() | -> __vfs_getxattr() | -> handler->get() /* lower filesystem callback */ |> posix_acl_fix_xattr_to_user() { 4 = make_kuid(&init_user_ns, 4); 4 = mapped_kuid_fs(&init_user_ns, 4); /* FAILURE */ -1 = from_kuid(0:10000000:65536 /* caller's idmapping */, 4); } As is easily seen the problem arises because the idmapping of the lower mount isn't taken into account as all of this happens in do_gexattr(). But do_getxattr() is always called on an overlayfs mount and inode and thus cannot possible take the idmapping of the lower layers into account. This problem is similar for fscaps but there the translation happens as part of vfs_getxattr() already. Let's walk through an fscaps overlayfs callchain: setcap 'cap_net_raw+ep' /var/lib/lxc/c2/rootfs/home/ubuntu/.bashrc The expected outcome here is that we'll receive the cap_net_raw capability as we are able to map the uid associated with the fscap to 0 within our container. IOW, we want to see 0 as the result of the idmapping translations. If the user chooses option (1) we get the following callchain for fscaps: idmapped mount /vol/contpool/merge: 0:10000000:65536 caller's idmapping: 0:10000000:65536 overlayfs idmapping (ofs->creator_cred): 0:0:4k /* initial idmapping */ sys_getxattr() -> path_getxattr() -> getxattr() -> do_getxattr() -> vfs_getxattr() -> xattr_getsecurity() -> security_inode_getsecurity() ________________________________ -> cap_inode_getsecurity() | | { V | 10000000 = make_kuid(0:0:4k /* overlayfs idmapping */, 10000000); | 10000000 = mapped_kuid_fs(0:0:4k /* no idmapped mount */, 10000000); | /* Expected result is 0 and thus that we own the fscap. */ | 0 = from_kuid(0:10000000:65536 /* caller's idmapping */, 10000000); | } | -> vfs_getxattr_alloc() | -> handler->get == ovl_other_xattr_get() | -> vfs_getxattr() | -> xattr_getsecurity() | -> security_inode_getsecurity() | -> cap_inode_getsecurity() | { | 0 = make_kuid(0:0:4k /* lower s_user_ns */, 0); | 10000000 = mapped_kuid_fs(0:10000000:65536 /* idmapped mount */, 0); | 10000000 = from_kuid(0:0:4k /* overlayfs idmapping */, 10000000); | |____________________________________________________________________| } -> vfs_getxattr_alloc() -> handler->get == /* lower filesystem callback */ And if the user chooses option (2) we get: idmapped mount /vol/contpool/merge: 0:10000000:65536 caller's idmapping: 0:10000000:65536 overlayfs idmapping (ofs->creator_cred): 0:10000000:65536 sys_getxattr() -> path_getxattr() -> getxattr() -> do_getxattr() -> vfs_getxattr() -> xattr_getsecurity() -> security_inode_getsecurity() _______________________________ -> cap_inode_getsecurity() | | { V | 10000000 = make_kuid(0:10000000:65536 /* overlayfs idmapping */, 0); | 10000000 = mapped_kuid_fs(0:0:4k /* no idmapped mount */, 10000000); | /* Expected result is 0 and thus that we own the fscap. */ | 0 = from_kuid(0:10000000:65536 /* caller's idmapping */, 10000000); | } | -> vfs_getxattr_alloc() | -> handler->get == ovl_other_xattr_get() | |-> vfs_getxattr() | -> xattr_getsecurity() | -> security_inode_getsecurity() | -> cap_inode_getsecurity() | { | 0 = make_kuid(0:0:4k /* lower s_user_ns */, 0); | 10000000 = mapped_kuid_fs(0:10000000:65536 /* idmapped mount */, 0); | 0 = from_kuid(0:10000000:65536 /* overlayfs idmapping */, 10000000); | |____________________________________________________________________| } -> vfs_getxattr_alloc() -> handler->get == /* lower filesystem callback */ We can see how the translation happens correctly in those cases as the conversion happens within the vfs_getxattr() helper. For POSIX ACLs we need to do something similar. However, in contrast to fscaps we cannot apply the fix directly to the kernel internal posix acl data structure as this would alter the cached values and would also require a rework of how we currently deal with POSIX ACLs in general which almost never take the filesystem idmapping into account (the noteable exception being FUSE but even there the implementation is special) and instead retrieve the raw values based on the initial idmapping. The correct values are then generated right before returning to userspace. The fix for this is to move taking the mount's idmapping into account directly in vfs_getxattr() instead of having it be part of posix_acl_fix_xattr_to_user(). To this end we simply move the idmapped mount translation into a separate step performed in vfs_{g,s}etxattr() instead of in posix_acl_fix_xattr_{from,to}_user(). To see how this fixes things let's go back to the original example. Assume the user chose option (1) and mounted overlayfs on top of idmapped mounts on the host: idmapped mount /vol/contpool/merge: 0:10000000:65536 caller's idmapping: 0:10000000:65536 overlayfs idmapping (ofs->creator_cred): 0:0:4k /* initial idmapping */ sys_getxattr() -> path_getxattr() -> getxattr() -> do_getxattr() |> vfs_getxattr() | |> __vfs_getxattr() | | -> handler->get == ovl_posix_acl_xattr_get() | | -> ovl_xattr_get() | | -> vfs_getxattr() | | |> __vfs_getxattr() | | | -> handler->get() /* lower filesystem callback */ | | |> posix_acl_getxattr_idmapped_mnt() | | { | | 4 = make_kuid(&init_user_ns, 4); | | 10000004 = mapped_kuid_fs(0:10000000:65536 /* lower idmapped mount */, 4); | | 10000004 = from_kuid(&init_user_ns, 10000004); | | |_______________________ | | } | | | | | |> posix_acl_getxattr_idmapped_mnt() | | { | | V | 10000004 = make_kuid(&init_user_ns, 10000004); | 10000004 = mapped_kuid_fs(&init_user_ns /* no idmapped mount */, 10000004); | 10000004 = from_kuid(&init_user_ns, 10000004); | } |_________________________________________________ | | | | |> posix_acl_fix_xattr_to_user() | { V 10000004 = make_kuid(0:0:4k /* init_user_ns */, 10000004); /* SUCCESS */ 4 = from_kuid(0:10000000:65536 /* caller's idmapping */, 10000004); } And similarly if the user chooses option (1) and mounted overayfs on top of idmapped mounts inside the container: idmapped mount /vol/contpool/merge: 0:10000000:65536 caller's idmapping: 0:10000000:65536 overlayfs idmapping (ofs->creator_cred): 0:10000000:65536 sys_getxattr() -> path_getxattr() -> getxattr() -> do_getxattr() |> vfs_getxattr() | |> __vfs_getxattr() | | -> handler->get == ovl_posix_acl_xattr_get() | | -> ovl_xattr_get() | | -> vfs_getxattr() | | |> __vfs_getxattr() | | | -> handler->get() /* lower filesystem callback */ | | |> posix_acl_getxattr_idmapped_mnt() | | { | | 4 = make_kuid(&init_user_ns, 4); | | 10000004 = mapped_kuid_fs(0:10000000:65536 /* lower idmapped mount */, 4); | | 10000004 = from_kuid(&init_user_ns, 10000004); | | |_______________________ | | } | | | | | |> posix_acl_getxattr_idmapped_mnt() | | { V | 10000004 = make_kuid(&init_user_ns, 10000004); | 10000004 = mapped_kuid_fs(&init_user_ns /* no idmapped mount */, 10000004); | 10000004 = from_kuid(0(&init_user_ns, 10000004); | |_________________________________________________ | } | | | |> posix_acl_fix_xattr_to_user() | { V 10000004 = make_kuid(0:0:4k /* init_user_ns */, 10000004); /* SUCCESS */ 4 = from_kuid(0:10000000:65536 /* caller's idmappings */, 10000004); } The last remaining problem we need to fix here is ovl_get_acl(). During ovl_permission() overlayfs will call: ovl_permission() -> generic_permission() -> acl_permission_check() -> check_acl() -> get_acl() -> inode->i_op->get_acl() == ovl_get_acl() > get_acl() /* on the underlying filesystem) ->inode->i_op->get_acl() == /*lower filesystem callback */ -> posix_acl_permission() passing through the get_acl request to the underlying filesystem. This will retrieve the acls stored in the lower filesystem without taking the idmapping of the underlying mount into account as this would mean altering the cached values for the lower filesystem. The simple solution is to have ovl_get_acl() simply duplicate the ACLs, update the values according to the idmapped mount and return it to acl_permission_check() so it can be used in posix_acl_permission(). Since overlayfs doesn't cache ACLs they'll be released right after. Link: https://github.com/brauner/mount-idmapped/issues/9 Cc: Seth Forshee <sforshee@digitalocean.com> Cc: Amir Goldstein <amir73il@gmail.com> Cc: Vivek Goyal <vgoyal@redhat.com> Cc: Christoph Hellwig <hch@lst.de> Cc: Aleksa Sarai <cyphar@cyphar.com> Cc: linux-unionfs@vger.kernel.org Signed-off-by: Christian Brauner (Microsoft) <brauner@kernel.org> Fixes: bc70682a497c ("ovl: support idmapped layers") Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>