On Thu, Jan 22, 2026 at 11:02:56AM -0500, Chuck Lever wrote: > From: Chuck Lever <[email protected]> > > Enable upper layers such as NFSD to retrieve case sensitivity > information from file systems by adding FS_XFLAG_CASEFOLD and > FS_XFLAG_CASENONPRESERVING flags. > > Filesystems report case-insensitive or case-nonpreserving behavior > by setting these flags directly in fa->fsx_xflags. The default > (flags unset) indicates POSIX semantics: case-sensitive and > case-preserving. These flags are read-only; userspace cannot set > them via ioctl. > > Remove struct file_kattr initialization from fileattr_fill_xflags() > and fileattr_fill_flags(). Callers at ioctl/syscall entry points > zero-initialize the struct themselves, which allows them to pass > hints (flags_valid, fsx_valid) to the filesystem's ->fileattr_get() > callback via the fa argument. Filesystem handlers that invoke these > fill functions can now set flags directly in fa->fsx_xflags before > calling them, without the fill functions zeroing those values.
In hindsight I regret not asking for the file_kattr initialization change to be in a separate patch. > Case sensitivity information is exported to userspace via the > fa_xflags field in the FS_IOC_FSGETXATTR ioctl and file_getattr() > system call. > > Signed-off-by: Chuck Lever <[email protected]> The UAPI changes still look ok to me. AFAICT the file_kattr initialization now seem like they don't zap fields to confuse vfs_fileattr_get. Reviewed-by: "Darrick J. Wong" <[email protected]> --D > --- > fs/file_attr.c | 12 ++++-------- > fs/xfs/xfs_ioctl.c | 2 +- > include/linux/fileattr.h | 3 ++- > include/uapi/linux/fs.h | 2 ++ > 4 files changed, 9 insertions(+), 10 deletions(-) > > diff --git a/fs/file_attr.c b/fs/file_attr.c > index 13cdb31a3e94..6e37040fc5fa 100644 > --- a/fs/file_attr.c > +++ b/fs/file_attr.c > @@ -15,12 +15,10 @@ > * @fa: fileattr pointer > * @xflags: FS_XFLAG_* flags > * > - * Set ->fsx_xflags, ->fsx_valid and ->flags (translated xflags). All > - * other fields are zeroed. > + * Set ->fsx_xflags, ->fsx_valid and ->flags (translated xflags). > */ > void fileattr_fill_xflags(struct file_kattr *fa, u32 xflags) > { > - memset(fa, 0, sizeof(*fa)); > fa->fsx_valid = true; > fa->fsx_xflags = xflags; > if (fa->fsx_xflags & FS_XFLAG_IMMUTABLE) > @@ -46,11 +44,9 @@ EXPORT_SYMBOL(fileattr_fill_xflags); > * @flags: FS_*_FL flags > * > * Set ->flags, ->flags_valid and ->fsx_xflags (translated flags). > - * All other fields are zeroed. > */ > void fileattr_fill_flags(struct file_kattr *fa, u32 flags) > { > - memset(fa, 0, sizeof(*fa)); > fa->flags_valid = true; > fa->flags = flags; > if (fa->flags & FS_SYNC_FL) > @@ -323,7 +319,7 @@ int ioctl_setflags(struct file *file, unsigned int __user > *argp) > { > struct mnt_idmap *idmap = file_mnt_idmap(file); > struct dentry *dentry = file->f_path.dentry; > - struct file_kattr fa; > + struct file_kattr fa = {}; > unsigned int flags; > int err; > > @@ -355,7 +351,7 @@ int ioctl_fssetxattr(struct file *file, void __user *argp) > { > struct mnt_idmap *idmap = file_mnt_idmap(file); > struct dentry *dentry = file->f_path.dentry; > - struct file_kattr fa; > + struct file_kattr fa = {}; > int err; > > err = copy_fsxattr_from_user(&fa, argp); > @@ -434,7 +430,7 @@ SYSCALL_DEFINE5(file_setattr, int, dfd, const char __user > *, filename, > struct filename *name __free(putname) = NULL; > unsigned int lookup_flags = 0; > struct file_attr fattr; > - struct file_kattr fa; > + struct file_kattr fa = {}; > int error; > > BUILD_BUG_ON(sizeof(struct file_attr) < FILE_ATTR_SIZE_VER0); > diff --git a/fs/xfs/xfs_ioctl.c b/fs/xfs/xfs_ioctl.c > index 59eaad774371..f0417c4d1fca 100644 > --- a/fs/xfs/xfs_ioctl.c > +++ b/fs/xfs/xfs_ioctl.c > @@ -496,7 +496,7 @@ xfs_ioc_fsgetxattra( > xfs_inode_t *ip, > void __user *arg) > { > - struct file_kattr fa; > + struct file_kattr fa = {}; > > xfs_ilock(ip, XFS_ILOCK_SHARED); > xfs_fill_fsxattr(ip, XFS_ATTR_FORK, &fa); > diff --git a/include/linux/fileattr.h b/include/linux/fileattr.h > index f89dcfad3f8f..709de829659f 100644 > --- a/include/linux/fileattr.h > +++ b/include/linux/fileattr.h > @@ -16,7 +16,8 @@ > > /* Read-only inode flags */ > #define FS_XFLAG_RDONLY_MASK \ > - (FS_XFLAG_PREALLOC | FS_XFLAG_HASATTR) > + (FS_XFLAG_PREALLOC | FS_XFLAG_HASATTR | \ > + FS_XFLAG_CASEFOLD | FS_XFLAG_CASENONPRESERVING) > > /* Flags to indicate valid value of fsx_ fields */ > #define FS_XFLAG_VALUES_MASK \ > diff --git a/include/uapi/linux/fs.h b/include/uapi/linux/fs.h > index 66ca526cf786..919148beaa8c 100644 > --- a/include/uapi/linux/fs.h > +++ b/include/uapi/linux/fs.h > @@ -253,6 +253,8 @@ struct file_attr { > #define FS_XFLAG_FILESTREAM 0x00004000 /* use filestream allocator */ > #define FS_XFLAG_DAX 0x00008000 /* use DAX for IO */ > #define FS_XFLAG_COWEXTSIZE 0x00010000 /* CoW extent size allocator > hint */ > +#define FS_XFLAG_CASEFOLD 0x00020000 /* case-insensitive lookups */ > +#define FS_XFLAG_CASENONPRESERVING 0x00040000 /* case not preserved */ > #define FS_XFLAG_HASATTR 0x80000000 /* no DIFLAG for this */ > > /* the read-only stuff doesn't really belong here, but any other place is > -- > 2.52.0 > > _______________________________________________ Linux-f2fs-devel mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/linux-f2fs-devel
