linux/fs/libfs.c, branch v6.7

libfs: getdents() should return 0 after reaching EOD

2023-11-20T14:34:22Z

The new directory offset helpers don't conform with the convention of getdents() returning no more entries once a directory file descriptor has reached the current end-of-directory. To address this, copy the logic from dcache_readdir() to mark the open directory file descriptor once EOD has been reached. Seeking resets the mark. Reported-by: Tavian Barnes Closes: https://lore.kernel.org/linux-fsdevel/20231113180616.2831430-1-tavianator@tavianator.com/ Fixes: 6faddda69f62 ("libfs: Add directory operations for stable offsets") Signed-off-by: Chuck Lever Link: https://lore.kernel.org/r/170043792492.4628.15646203084646716134.stgit@bazille.1015granger.net Signed-off-by: Christian Brauner

Merge tag 'vfs-6.7.fsid' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs

2023-11-07T20:11:26Z

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

fs: fix build error with CONFIG_EXPORTFS=m or not defined

2023-10-28T14:16:19Z

Many of the filesystems that call the generic exportfs helpers do not select the EXPORTFS config. Move generic_encode_ino32_fh() to libfs.c, same as generic_fh_to_*() to avoid having to fix all those config dependencies. Reported-by: kernel test robot Closes: https://lore.kernel.org/oe-kbuild-all/202310262151.renqMvme-lkp@intel.com/ Fixes: dfaf653dc415 ("exportfs: make ->encode_fh() a mandatory method for NFS export") Suggested-by: Arnd Bergmann Signed-off-by: Amir Goldstein Link: https://lore.kernel.org/r/20231026204540.143217-1-amir73il@gmail.com Tested-by: Arnd Bergmann Signed-off-by: Christian Brauner

fs: report f_fsid from s_dev for "simple" filesystems

2023-10-28T14:16:18Z

There are many "simple" filesystems (*) that report null f_fsid in statfs(2). Those "simple" filesystems report sb->s_dev as the st_dev field of the stat syscalls for all inodes of the filesystem (**). In order to enable fanotify reporting of events with fsid on those "simple" filesystems, report the sb->s_dev number in f_fsid field of statfs(2). (*) For most of the "simple" filesystem refered to in this commit, the ->statfs() operation is simple_statfs(). Some of those fs assign the simple_statfs() method directly in their ->s_op struct and some assign it indirectly via a call to simple_fill_super() or to pseudo_fs_fill_super() with either custom or "simple" s_op. We also make the same change to efivarfs and hugetlbfs, although they do not use simple_statfs(), because they use the simple_* inode opreations (e.g. simple_lookup()). (**) For most of the "simple" filesystems, the ->getattr() method is not assigned, so stat() is implemented by generic_fillattr(). A few "simple" filesystem use the simple_getattr() method which also calls generic_fillattr() to fill most of the stat struct. The two exceptions are procfs and 9p. procfs implements several different ->getattr() methods, but they all end up calling generic_fillattr() to fill the st_dev field from sb->s_dev. 9p has more complicated ->getattr() methods, but they too, end up calling generic_fillattr() to fill the st_dev field from sb->s_dev. Note that 9p and kernfs also call simple_statfs() from custom ->statfs() methods which already fill the f_fsid field, but v9fs_statfs() calls simple_statfs() only in case f_fsid was not filled and kenrfs_statfs() overwrites f_fsid after calling simple_statfs(). Link: https://lore.kernel.org/r/20230919094820.g5bwharbmy2dq46w@quack3/ Signed-off-by: Amir Goldstein Link: https://lore.kernel.org/r/20231023143049.2944970-1-amir73il@gmail.com Reviewed-by: Jan Kara Signed-off-by: Christian Brauner

fs: new accessor methods for atime and mtime

2023-10-18T11:26:14Z

Recently, we converted the ctime accesses in the kernel to use new accessor functions. Linus recently pointed out though that if we add accessors for the atime and mtime, then that would allow us to seamlessly change how these timestamps are stored in the inode. Add new accessor functions for the atime and mtime that mirror the accessors for the ctime. Signed-off-by: Jeff Layton Link: https://lore.kernel.org/r/20231004185239.80830-1-jlayton@kernel.org Signed-off-by: Christian Brauner

direct_write_fallback(): on error revert the ->ki_pos update from buffered write

2023-09-20T12:22:01Z

If we fail filemap_write_and_wait_range() on the range the buffered write went into, we only report the "number of bytes which we direct-written", to quote the comment in there. Which is fine, but buffered write has already advanced iocb->ki_pos, so we need to roll that back. Otherwise we end up with e.g. write(2) advancing position by more than the amount it reports having written. Fixes: 182c25e9c157 "filemap: update ki_pos in generic_perform_write" Signed-off-by: Al Viro Message-Id: <20230827214518.GU3390869@ZenIV> Signed-off-by: Christian Brauner

Merge tag 'ext4_for_linus-6.6-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4

2023-08-31T22:18:15Z

Pull ext4 updates from Ted Ts'o: "Many ext4 and jbd2 cleanups and bug fixes: - Cleanups in the ext4 remount code when going to and from read-only - Cleanups in ext4's multiblock allocator - Cleanups in the jbd2 setup/mounting code paths - Performance improvements when appending to a delayed allocation file - Miscellaneous syzbot and other bug fixes" * tag 'ext4_for_linus-6.6-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4: (60 commits) ext4: fix slab-use-after-free in ext4_es_insert_extent() libfs: remove redundant checks of s_encoding ext4: remove redundant checks of s_encoding ext4: reject casefold inode flag without casefold feature ext4: use LIST_HEAD() to initialize the list_head in mballoc.c ext4: do not mark inode dirty every time when appending using delalloc ext4: rename s_error_work to s_sb_upd_work ext4: add periodic superblock update check ext4: drop dio overwrite only flag and associated warning ext4: add correct group descriptors and reserved GDT blocks to system zone ext4: remove unused function declaration ext4: mballoc: avoid garbage value from err ext4: use sbi instead of EXT4_SB(sb) in ext4_mb_new_blocks_simple() ext4: change the type of blocksize in ext4_mb_init_cache() ext4: fix unttached inode after power cut with orphan file feature enabled jbd2: correct the end of the journal recovery scan range ext4: ext4_get_{dev}_journal return proper error value ext4: cleanup ext4_get_dev_journal() and ext4_get_journal() jbd2: jbd2_journal_init_{dev,inode} return proper error return value jbd2: drop useless error tag in jbd2_journal_wipe() ...

Merge tag 'v6.6-vfs.misc' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs

2023-08-28T17:17:14Z

Pull misc vfs updates from Christian Brauner: "This contains the usual miscellaneous features, cleanups, and fixes for vfs and individual filesystems. Features: - Block mode changes on symlinks and rectify our broken semantics - Report file modifications via fsnotify() for splice - Allow specifying an explicit timeout for the "rootwait" kernel command line option. This allows to timeout and reboot instead of always waiting indefinitely for the root device to show up - Use synchronous fput for the close system call Cleanups: - Get rid of open-coded lockdep workarounds for async io submitters and replace it all with a single consolidated helper - Simplify epoll allocation helper - Convert simple_write_begin and simple_write_end to use a folio - Convert page_cache_pipe_buf_confirm() to use a folio - Simplify __range_close to avoid pointless locking - Disable per-cpu buffer head cache for isolated cpus - Port ecryptfs to kmap_local_page() api - Remove redundant initialization of pointer buf in pipe code - Unexport the d_genocide() function which is only used within core vfs - Replace printk(KERN_ERR) and WARN_ON() with WARN() Fixes: - Fix various kernel-doc issues - Fix refcount underflow for eventfds when used as EFD_SEMAPHORE - Fix a mainly theoretical issue in devpts - Check the return value of __getblk() in reiserfs - Fix a racy assert in i_readcount_dec - Fix integer conversion issues in various functions - Fix LSM security context handling during automounts that prevented NFS superblock sharing" * tag 'v6.6-vfs.misc' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs: (39 commits) cachefiles: use kiocb_{start,end}_write() helpers ovl: use kiocb_{start,end}_write() helpers aio: use kiocb_{start,end}_write() helpers io_uring: use kiocb_{start,end}_write() helpers fs: create kiocb_{start,end}_write() helpers fs: add kerneldoc to file_{start,end}_write() helpers io_uring: rename kiocb_end_write() local helper splice: Convert page_cache_pipe_buf_confirm() to use a folio libfs: Convert simple_write_begin and simple_write_end to use a folio fs/dcache: Replace printk and WARN_ON by WARN fs/pipe: remove redundant initialization of pointer buf fs: Fix kernel-doc warnings devpts: Fix kernel-doc warnings doc: idmappings: fix an error and rephrase a paragraph init: Add support for rootwait timeout parameter vfs: fix up the assert in i_readcount_dec fs: Fix one kernel-doc comment docs: filesystems: idmappings: clarify from where idmappings are taken fs/buffer.c: disable per-CPU buffer_head cache for isolated CPUs vfs, security: Fix automount superblock LSM init problem, preventing NFS sb sharing ...

Merge tag 'v6.6-vfs.tmpfs' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs

2023-08-28T16:55:25Z

Pull libfs and tmpfs updates from Christian Brauner: "This cycle saw a lot of work for tmpfs that required changes to the vfs layer. Andrew, Hugh, and I decided to take tmpfs through vfs this cycle. Things will go back to mm next cycle. Features ======== - By far the biggest work is the quota support for tmpfs. New tmpfs quota infrastructure is added to support it and a new QFMT_SHMEM uapi option is exposed. This offers user and group quotas to tmpfs (project quotas will be added later). Similar to other filesystems tmpfs quota are not supported within user namespaces yet. - Add support for user xattrs. While tmpfs already supports security xattrs (security.*) and POSIX ACLs for a long time it lacked support for user xattrs (user.*). With this pull request tmpfs will be able to support a limited number of user xattrs. This is accompanied by a fix (see below) to limit persistent simple xattr allocations. - Add support for stable directory offsets. Currently tmpfs relies on the libfs provided cursor-based mechanism for readdir. This causes issues when a tmpfs filesystem is exported via NFS. NFS clients do not open directories. Instead, each server-side readdir operation opens the directory, reads it, and then closes it. Since the cursor state for that directory is associated with the opened file it is discarded after each readdir operation. Such directory offsets are not just cached by NFS clients but also various userspace libraries based on these clients. As it stands there is no way to invalidate the caches when directory offsets have changed and the whole application depends on unchanging directory offsets. At LSFMM we discussed how to solve this problem and decided to support stable directory offsets. libfs now allows filesystems like tmpfs to use an xarrary to map a directory offset to a dentry. This mechanism is currently only used by tmpfs but can be supported by others as well. Fixes ===== - Change persistent simple xattrs allocations in libfs from GFP_KERNEL to GPF_KERNEL_ACCOUNT so they're subject to memory cgroup limits. Since this is a change to libfs it affects both tmpfs and kernfs. - Correctly verify {g,u}id mount options. A new filesystem context is created via fsopen() which records the namespace that becomes the owning namespace of the superblock when fsconfig(FSCONFIG_CMD_CREATE) is called for filesystems that are mountable in namespaces. However, fsconfig() calls can occur in a namespace different from the namespace where fsopen() has been called. Currently, when fsconfig() is called to set {g,u}id mount options the requested {g,u}id is mapped into a k{g,u}id according to the namespace where fsconfig() was called from. The resulting k{g,u}id is not guaranteed to be resolvable in the namespace of the filesystem (the one that fsopen() was called in). This means it's possible for an unprivileged user to create files owned by any group in a tmpfs mount since it's possible to set the setid bits on the tmpfs directory. The contract for {g,u}id mount options and {g,u}id values in general set from userspace has always been that they are translated according to the caller's idmapping. In so far, tmpfs has been doing the correct thing. But since tmpfs is mountable in unprivileged contexts it is also necessary to verify that the resulting {k,g}uid is representable in the namespace of the superblock to avoid such bugs. The new mount api's cross-namespace delegation abilities are already widely used. Having talked to a bunch of userspace this is the most faithful solution with minimal regression risks" * tag 'v6.6-vfs.tmpfs' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs: tmpfs,xattr: GFP_KERNEL_ACCOUNT for simple xattrs mm: invalidation check mapping before folio_contains tmpfs: trivial support for direct IO tmpfs,xattr: enable limited user extended attributes tmpfs: track free_ispace instead of free_inodes xattr: simple_xattr_set() return old_xattr to be freed tmpfs: verify {g,u}id mount options correctly shmem: move spinlock into shmem_recalc_inode() to fix quota support libfs: Remove parent dentry locking in offset_iterate_dir() libfs: Add a lock class for the offset map's xa_lock shmem: stable directory offsets shmem: Refactor shmem_symlink() libfs: Add directory operations for stable offsets shmem: fix quota lock nesting in huge hole handling shmem: Add default quota limit mount options shmem: quota support shmem: prepare shmem quota infrastructure quota: Check presence of quota operation structures instead of ->quota_read and ->quota_write callbacks shmem: make shmem_get_inode() return ERR_PTR instead of NULL shmem: make shmem_inode_acct_block() return error

libfs: remove redundant checks of s_encoding

2023-08-27T15:27:13Z

Now that neither ext4 nor f2fs allows inodes with the casefold flag to be instantiated when unsupported, it's unnecessary to repeatedly check for support later on during random filesystem operations. Signed-off-by: Eric Biggers Link: https://lore.kernel.org/r/20230814182903.37267-4-ebiggers@kernel.org Signed-off-by: Theodore Ts'o