kernel/linux.git/fs/dcache.c, branch v7.1-rc5

Merge tag 'pull-dcache-busy-wait' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs

2026-04-21T14:30:44+00:00

Pull dcache busy loop updates from Al Viro: "Fix livelocks in shrink_dcache_tree() If shrink_dcache_tree() finds a dentry in the middle of being killed by another thread, it has to wait until the victim finishes dying, gets detached from the tree and ceases to pin its parent. The way we used to deal with that amounted to busy-wait; unfortunately, it's not just inefficient but can lead to reliably reproducible hard livelocks. Solved by having shrink_dentry_tree() attach a completion to such dentry, with dentry_unlist() calling complete() on all objects attached to it. With a bit of care it can be done without growing struct dentry or adding overhead in normal case" * tag 'pull-dcache-busy-wait' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: get rid of busy-waiting in shrink_dcache_tree() dcache.c: more idiomatic "positives are not allowed" sanity checks struct dentry: make ->d_u anonymous for_each_alias(): helper macro for iterating through dentries of given inode

vfs: get rid of BUG_ON() in d_mark_tmpfile_name()

2026-04-14T17:01:12+00:00

Do proper error handling in d_mark_tmpfile_name() by returning errors rather than using BUG_ON()'s. Adjust caller to check for errors from d_mark_tmpfile_name() as well as clean it up for using return value from scnprintf() in QSTR_LEN() to make it more obvious where the tmpfile name's length is coming from. Link: https://lore.kernel.org/r/CAHk-=wgerpUKCDhdzKH0FEdLyfhj3doc9t+kO9Yb6rSsTp7hdQ@mail.gmail.com Suggested-by: Linus Torvalds Reviewed-by: David Howells Signed-off-by: Paulo Alcantara (Red Hat) Cc: Christian Brauner Cc: Jan Kara CC: linux-fsdevel@vger.kernel.org Cc: linux-cifs@vger.kernel.org Signed-off-by: Steve French

Merge tag 'v7.1-rc1-part1-smb3-client-fixes' of git://git.samba.org/sfrench/cifs-2.6

2026-04-14T00:09:00+00:00

Pull smb client updates from Steve French: - Fix EAs bounds check - Fix OOB read in symlink response parsing - Add support for creating tmpfiles - Minor debug improvement for mount failure - Minor crypto cleanup - Add missing module description - mount fix for lease vs. nolease - Add Metze as maintainer for smbdirect - Minor error mapping header cleanup - Improve search speed of SMB1 maperror - Fix potential null ptr ref in smb2 map error tests * tag 'v7.1-rc1-part1-smb3-client-fixes' of git://git.samba.org/sfrench/cifs-2.6: (26 commits) smb: client: allow both 'lease' and 'nolease' mount options smb: client: get rid of d_drop()+d_add() smb: client: set ATTR_TEMPORARY with O_TMPFILE | O_EXCL smb: client: add support for O_TMPFILE vfs: introduce d_mark_tmpfile_name() MAINTAINERS: create entry for smbdirect smb: client: add missing MODULE_DESCRIPTION() to smb1maperror_test smb: client: fix OOB reads parsing symlink error response smb: client: fix off-by-8 bounds check in check_wsl_eas() smb: client: Remove unnecessary selection of CRYPTO_ECB smb/client: move smb2maperror declarations to smb2proto.h smb/client: introduce KUnit tests to check DOS/SRV err mapping search smb/client: check if SMB1 DOS/SRV error mapping arrays are sorted smb/client: use binary search for SMB1 DOS/SRV error mapping smb/client: autogenerate SMB1 DOS/SRV to POSIX error mapping smb/client: annotate smberr.h with POSIX error codes smb/client: move ERRnetlogonNotStarted to DOS error class smb/client: introduce KUnit test to check ntstatus_to_dos_map search smb/client: check if ntstatus_to_dos_map is sorted smb/client: use binary search for NT status to DOS mapping ...

Merge tag 'vfs-7.1-rc1.misc' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs

2026-04-13T21:20:11+00:00

Pull misc vfs updates from Christian Brauner: "Features: - coredump: add tracepoint for coredump events - fs: hide file and bfile caches behind runtime const machinery Fixes: - fix architecture-specific compat_ftruncate64 implementations - dcache: Limit the minimal number of bucket to two - fs/omfs: reject s_sys_blocksize smaller than OMFS_DIR_START - fs/mbcache: cancel shrink work before destroying the cache - dcache: permit dynamic_dname()s up to NAME_MAX Cleanups: - remove or unexport unused fs_context infrastructure - trivial ->setattr cleanups - selftests/filesystems: Assume that TIOCGPTPEER is defined - writeback: fix kernel-doc function name mismatch for wb_put_many() - autofs: replace manual symlink buffer allocation in autofs_dir_symlink - init/initramfs.c: trivial fix: FSM -> Finite-state machine - fs: remove stale and duplicate forward declarations - readdir: Introduce dirent_size() - fs: Replace user_access_{begin/end} by scoped user access - kernel: acct: fix duplicate word in comment - fs: write a better comment in step_into() concerning .mnt assignment - fs: attr: fix comment formatting and spelling issues" * tag 'vfs-7.1-rc1.misc' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs: (28 commits) dcache: permit dynamic_dname()s up to NAME_MAX fs: attr: fix comment formatting and spelling issues fs: hide file and bfile caches behind runtime const machinery fs: write a better comment in step_into() concerning .mnt assignment proc: rename proc_notify_change to proc_setattr proc: rename proc_setattr to proc_nochmod_setattr affs: rename affs_notify_change to affs_setattr adfs: rename adfs_notify_change to adfs_setattr hfs: update comments on hfs_inode_setattr kernel: acct: fix duplicate word in comment fs: Replace user_access_{begin/end} by scoped user access readdir: Introduce dirent_size() coredump: add tracepoint for coredump events fs: remove do_sys_truncate fs: pass on FTRUNCATE_* flags to do_truncate fs: fix archiecture-specific compat_ftruncate64 fs: remove stale and duplicate forward declarations init/initramfs.c: trivial fix: FSM -> Finite-state machine autofs: replace manual symlink buffer allocation in autofs_dir_symlink fs/mbcache: cancel shrink work before destroying the cache ...

vfs: introduce d_mark_tmpfile_name()

2026-04-10T16:25:34+00:00

CIFS requires O_TMPFILE dentries to have names of newly created delete-on-close files in the server so it can build full pathnames from the root of the share when performing operations on them. Suggested-by: Al Viro Signed-off-by: Paulo Alcantara (Red Hat) Cc: Christian Brauner Cc: Jan Kara Cc: David Howells Cc: Matthew Wilcox Cc: linux-fsdevel@vger.kernel.org Cc: linux-cifs@vger.kernel.org Signed-off-by: Steve French

get rid of busy-waiting in shrink_dcache_tree()

2026-04-04T08:03:56+00:00

If shrink_dcache_tree() runs into a potential victim that is already dying, it must wait for that dentry to go away. To avoid busy-waiting we need some object to wait on and a way for dentry_unlist() to see that we need to be notified. The obvious place for the object to wait on would be on our stack frame. We will store a pointer to that object (struct completion_list) in victim dentry; if there's more than one thread wanting to wait for the same dentry to finish dying, we'll have their instances linked into a list, with reference in dentry pointing to the head of that list. * new object - struct completion_list. A pair of struct completion and pointer to the next instance. That's what shrink_dcache_tree() will wait on if needed. * add a new member (->waiters, opaque pointer to struct completion_list) to struct dentry. It is defined for negative live dentries that are not in-lookup ones and it will remain NULL for almost all of them. It does not conflict with ->d_rcu (defined for killed dentries), ->d_alias (defined for positive dentries, all live) or ->d_in_lookup_hash (defined for in-lookup dentries, all live negative). That allows to colocate all four members. * make sure that all places where dentry enters the state where ->waiters is defined (live, negative, not-in-lookup) initialize ->waiters to NULL. * if select_collect2() runs into a dentry that is already dying, have its caller insert a local instance of struct completion_list into the head of the list hanging off dentry->waiters and wait for completion. * if dentry_unlist() sees non-NULL ->waiters, have it carefully walk through the completion_list instances in that list, calling complete() for each. For now struct completion_list is local to fs/dcache.c; it's obviously dentry-agnostic, and it can be trivially lifted into linux/completion.h if somebody finds a reason to do so... Signed-off-by: Al Viro

dcache.c: more idiomatic "positives are not allowed" sanity checks

2026-04-02T08:09:37+00:00

Several functions have BUG_ON/WARN_ON sanity checks that want to verify that dentry is not positive and instead of looking at ->d_inode (as we do in all other places that check that) they look at ->d_alias. Just use the normal helpers instead - that way we no longer even look at ->d_alias for negative dentries Signed-off-by: Al Viro

struct dentry: make ->d_u anonymous

2026-04-02T07:47:31+00:00

Making ->d_rcu and (then) ->d_child overlapping dates back to 2006; anon unions support had been added to gcc only in 4.6 (2011) and the minimal gcc version hadn't been bumped to that until 4.19 (2018). These days there's no reason not to keep that union named. Signed-off-by: Al Viro

for_each_alias(): helper macro for iterating through dentries of given inode

2026-04-02T07:45:02+00:00

Most of the places using d_alias are loops iterating through all aliases for given inode; introduce a helper macro (for_each_alias(dentry, inode)) and convert open-coded instances of such loop to it. They are easier to read that way and it reduces the noise on the next steps. You _must_ hold inode->i_lock over that thing. Signed-off-by: Al Viro

treewide: change inode->i_ino from unsigned long to u64

2026-03-06T13:31:28+00:00

On 32-bit architectures, unsigned long is only 32 bits wide, which causes 64-bit inode numbers to be silently truncated. Several filesystems (NFS, XFS, BTRFS, etc.) can generate inode numbers that exceed 32 bits, and this truncation can lead to inode number collisions and other subtle bugs on 32-bit systems. Change the type of inode->i_ino from unsigned long to u64 to ensure that inode numbers are always represented as 64-bit values regardless of architecture. Update all format specifiers treewide from %lu/%lx to %llu/%llx to match the new type, along with corresponding local variable types. This is the bulk treewide conversion. Earlier patches in this series handled trace events separately to allow trace field reordering for better struct packing on 32-bit. Signed-off-by: Jeff Layton Link: https://patch.msgid.link/20260304-iino-u64-v3-12-2257ad83d372@kernel.org Acked-by: Damien Le Moal Reviewed-by: Christoph Hellwig Reviewed-by: Jan Kara Reviewed-by: Chuck Lever Signed-off-by: Christian Brauner