[PATCH v2 3/6] ntfs3: Implement fileattr_get for case sensitivity

Chuck Lever
2025-12-11T15:21:55Z

From: Chuck Lever <chuck.lever@oracle.com>

Report NTFS case sensitivity behavior via the new file_kattr
case_info field. NTFS always preserves case at rest.

Case sensitivity depends on mount options: with "nocase", NTFS
performs Unicode case-insensitive matching; otherwise it is
case-sensitive.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
---
fs/ntfs3/file.c | 27 +++++++++++++++++++++++++++
fs/ntfs3/inode.c | 1 +
fs/ntfs3/namei.c | 2 ++
fs/ntfs3/ntfs_fs.h | 1 +
4 files changed, 31 insertions(+)

diff --git a/fs/ntfs3/file.c b/fs/ntfs3/file.c
index 4c90ec2fa2ea..35892988b788 100644
--- a/fs/ntfs3/file.c
+++ b/fs/ntfs3/file.c
@@ -104,6 +104,32 @@ long ntfs_compat_ioctl(struct file *filp, u32 cmd, unsigned long arg)
}
#endif

+/*
+ * ntfs_fileattr_get - inode_operations::fileattr_get
+ */
+int ntfs_fileattr_get(struct dentry *dentry, struct file_kattr *fa)
+{
+ struct inode *inode = d_inode(dentry);
+ struct ntfs_sb_info *sbi = inode->i_sb->s_fs_info;
+
+ /* Avoid any operation if inode is bad. */
+ if (unlikely(is_bad_ni(ntfs_i(inode))))
+ return -EINVAL;
+
+ /*
+ * NTFS preserves case. Case sensitivity depends on mount options:
+ * with "nocase" mount option, NTFS is case-insensitive using
+ * Unicode case folding; otherwise it is case-sensitive.
+ */
+ if (sbi->options && sbi->options->nocase)
+ fa->case_info = FILEATTR_CASEFOLD_UNICODE |
+ FILEATTR_CASE_PRESERVING;
+ else
+ fa->case_info = FILEATTR_CASEFOLD_NONE |
+ FILEATTR_CASE_PRESERVING;
+ return 0;
+}
+
/*
* ntfs_getattr - inode_operations::getattr
*/
@@ -1383,6 +1409,7 @@ const struct inode_operations ntfs_file_inode_operations = {
.get_acl = ntfs_get_acl,
.set_acl = ntfs_set_acl,
.fiemap = ntfs_fiemap,
+ .fileattr_get = ntfs_fileattr_get,
};

const struct file_operations ntfs_file_operations = {
diff --git a/fs/ntfs3/inode.c b/fs/ntfs3/inode.c
index 3959f23c487a..ecdea6d83980 100644
--- a/fs/ntfs3/inode.c
+++ b/fs/ntfs3/inode.c
@@ -2085,6 +2085,7 @@ const struct inode_operations ntfs_link_inode_operations = {
.get_link = ntfs_get_link,
.setattr = ntfs_setattr,
.listxattr = ntfs_listxattr,
+ .fileattr_get = ntfs_fileattr_get,
};

const struct address_space_operations ntfs_aops = {
diff --git a/fs/ntfs3/namei.c b/fs/ntfs3/namei.c
index 82c8ae56beee..2094e5409e43 100644
--- a/fs/ntfs3/namei.c
+++ b/fs/ntfs3/namei.c
@@ -519,6 +519,7 @@ const struct inode_operations ntfs_dir_inode_operations = {
.getattr = ntfs_getattr,
.listxattr = ntfs_listxattr,
.fiemap = ntfs_fiemap,
+ .fileattr_get = ntfs_fileattr_get,
};

const struct inode_operations ntfs_special_inode_operations = {
@@ -527,6 +528,7 @@ const struct inode_operations ntfs_special_inode_operations = {
.listxattr = ntfs_listxattr,
.get_acl = ntfs_get_acl,
.set_acl = ntfs_set_acl,
+ .fileattr_get = ntfs_fileattr_get,
};

const struct dentry_operations ntfs_dentry_ops = {
diff --git a/fs/ntfs3/ntfs_fs.h b/fs/ntfs3/ntfs_fs.h
index 630128716ea7..a178ca66e2e0 100644
--- a/fs/ntfs3/ntfs_fs.h
+++ b/fs/ntfs3/ntfs_fs.h
@@ -503,6 +503,7 @@ extern const struct file_operations ntfs_dir_operations;
extern const struct file_operations ntfs_legacy_dir_operations;

/* Globals from file.c */
+int ntfs_fileattr_get(struct dentry *dentry, struct file_kattr *fa);
int ntfs_getattr(struct mnt_idmap *idmap, const struct path *path,
struct kstat *stat, u32 request_mask, u32 flags);
int ntfs_setattr(struct mnt_idmap *idmap, struct dentry *dentry,
--
2.52.0