Merge branch 'vfs-7.2.casefold' into vfs.all

Signed-off-by: Christian Brauner <brauner@kernel.org>
author: Christian Brauner <brauner@kernel.org> 2026-05-21 15:34:12 +0200
committer: Christian Brauner <brauner@kernel.org> 2026-05-21 15:34:12 +0200
commit: fda3760fe867b3c5fda044d7fed4ae969a992f7a (patch)
tree: 2cf63af290a57f6997c15cfea39df561f89591aa /fs
parent: 82ff857a1878bb9502bf66ba73677a47679240f9 (diff)
parent: ea3120fd5153c967efb20e6e3330caecbf9d8b0a (diff)
download: linux-next-history-fda3760fe867b3c5fda044d7fed4ae969a992f7a.tar.gz
43 files changed, 587 insertions, 53 deletions
diff --git a/fs/exfat/exfat_fs.h b/fs/exfat/exfat_fs.h
index 89ef5368277f8..aff4dcd4e75a5 100644
--- a/fs/exfat/exfat_fs.h
+++ b/fs/exfat/exfat_fs.h
@@ -496,6 +496,8 @@ int exfat_setattr(struct mnt_idmap *idmap, struct dentry *dentry,
 int exfat_getattr(struct mnt_idmap *idmap, const struct path *path,
 		  struct kstat *stat, unsigned int request_mask,
 		  unsigned int query_flags);
+struct file_kattr;
+int exfat_fileattr_get(struct dentry *dentry, struct file_kattr *fa);
 int exfat_file_fsync(struct file *file, loff_t start, loff_t end, int datasync);
 long exfat_ioctl(struct file *filp, unsigned int cmd, unsigned long arg);
 long exfat_compat_ioctl(struct file *filp, unsigned int cmd,
diff --git a/fs/exfat/file.c b/fs/exfat/file.c
index 354bdcfe4abcd..91e5511945d11 100644
--- a/fs/exfat/file.c
+++ b/fs/exfat/file.c
@@ -14,6 +14,7 @@
 #include <linux/writeback.h>
 #include <linux/filelock.h>
 #include <linux/falloc.h>
+#include <linux/fileattr.h>
 
 #include "exfat_raw.h"
 #include "exfat_fs.h"
@@ -323,6 +324,18 @@ int exfat_getattr(struct mnt_idmap *idmap, const struct path *path,
 	return 0;
 }
 
+int exfat_fileattr_get(struct dentry *dentry, struct file_kattr *fa)
+{
+	/*
+	 * exFAT compares filenames through an upcase table, so lookup
+	 * is always case-insensitive. Long names are stored in UTF-16
+	 * with case intact; CASENONPRESERVING stays clear.
+	 */
+	fa->fsx_xflags |= FS_XFLAG_CASEFOLD;
+	fa->flags |= FS_CASEFOLD_FL;
+	return 0;
+}
+
 int exfat_setattr(struct mnt_idmap *idmap, struct dentry *dentry,
 		  struct iattr *attr)
 {
@@ -817,6 +830,7 @@ const struct file_operations exfat_file_operations = {
 };
 
 const struct inode_operations exfat_file_inode_operations = {
-	.setattr     = exfat_setattr,
-	.getattr     = exfat_getattr,
+	.setattr	= exfat_setattr,
+	.getattr	= exfat_getattr,
+	.fileattr_get	= exfat_fileattr_get,
 };
diff --git a/fs/exfat/namei.c b/fs/exfat/namei.c
index 2c5636634b4a4..94002e43db08d 100644
--- a/fs/exfat/namei.c
+++ b/fs/exfat/namei.c
@@ -1311,4 +1311,5 @@ const struct inode_operations exfat_dir_inode_operations = {
 	.rename		= exfat_rename,
 	.setattr	= exfat_setattr,
 	.getattr	= exfat_getattr,
+	.fileattr_get	= exfat_fileattr_get,
 };
diff --git a/fs/fat/fat.h b/fs/fat/fat.h
index 5a58f0bf8ce83..99ed9228a677b 100644
--- a/fs/fat/fat.h
+++ b/fs/fat/fat.h
@@ -10,6 +10,8 @@
 #include <linux/fs_context.h>
 #include <linux/fs_parser.h>
 
+struct file_kattr;
+
 /*
  * vfat shortname flags
  */
@@ -408,6 +410,7 @@ extern void fat_truncate_blocks(struct inode *inode, loff_t offset);
 extern int fat_getattr(struct mnt_idmap *idmap,
 		       const struct path *path, struct kstat *stat,
 		       u32 request_mask, unsigned int flags);
+int fat_fileattr_get(struct dentry *dentry, struct file_kattr *fa);
 extern int fat_file_fsync(struct file *file, loff_t start, loff_t end,
 			  int datasync);
 
diff --git a/fs/fat/file.c b/fs/fat/file.c
index becccdd2e501a..37e7049b4c8c4 100644
--- a/fs/fat/file.c
+++ b/fs/fat/file.c
@@ -17,6 +17,7 @@
 #include <linux/fsnotify.h>
 #include <linux/security.h>
 #include <linux/falloc.h>
+#include <linux/fileattr.h>
 #include "fat.h"
 
 static long fat_fallocate(struct file *file, int mode,
@@ -398,6 +399,40 @@ void fat_truncate_blocks(struct inode *inode, loff_t offset)
 	fat_flush_inodes(inode->i_sb, inode, NULL);
 }
 
+int fat_fileattr_get(struct dentry *dentry, struct file_kattr *fa)
+{
+	struct msdos_sb_info *sbi = MSDOS_SB(dentry->d_sb);
+	bool case_sensitive;
+
+	/*
+	 * FAT filesystems are case-insensitive by default. VFAT
+	 * becomes case-sensitive when mounted with 'check=strict',
+	 * which installs vfat_dentry_ops. MSDOS has no such option;
+	 * its 'nocase' mount option selects case-sensitive matching.
+	 *
+	 * VFAT long filename entries preserve case. Without VFAT, only
+	 * uppercased 8.3 short names are stored. MSDOS with 'nocase'
+	 * also preserves case.
+	 */
+	if (sbi->options.isvfat)
+		case_sensitive = sbi->options.name_check == 's';
+	else
+		case_sensitive = sbi->options.nocase;
+
+	if (!case_sensitive) {
+		fa->fsx_xflags |= FS_XFLAG_CASEFOLD;
+		fa->flags |= FS_CASEFOLD_FL;
+		if (!sbi->options.isvfat)
+			fa->fsx_xflags |= FS_XFLAG_CASENONPRESERVING;
+	}
+	if (d_inode(dentry)->i_flags & S_IMMUTABLE) {
+		fa->fsx_xflags |= FS_XFLAG_IMMUTABLE;
+		fa->flags |= FS_IMMUTABLE_FL;
+	}
+	return 0;
+}
+EXPORT_SYMBOL_GPL(fat_fileattr_get);
+
 int fat_getattr(struct mnt_idmap *idmap, const struct path *path,
 		struct kstat *stat, u32 request_mask, unsigned int flags)
 {
@@ -575,5 +610,6 @@ EXPORT_SYMBOL_GPL(fat_setattr);
 const struct inode_operations fat_file_inode_operations = {
 	.setattr	= fat_setattr,
 	.getattr	= fat_getattr,
+	.fileattr_get	= fat_fileattr_get,
 	.update_time	= fat_update_time,
 };
diff --git a/fs/fat/namei_msdos.c b/fs/fat/namei_msdos.c
index 4cc65f330fb7e..0fd2971ad4b13 100644
--- a/fs/fat/namei_msdos.c
+++ b/fs/fat/namei_msdos.c
@@ -644,6 +644,7 @@ static const struct inode_operations msdos_dir_inode_operations = {
 	.rename		= msdos_rename,
 	.setattr	= fat_setattr,
 	.getattr	= fat_getattr,
+	.fileattr_get	= fat_fileattr_get,
 	.update_time	= fat_update_time,
 };
 
diff --git a/fs/fat/namei_vfat.c b/fs/fat/namei_vfat.c
index 918b3756674c3..e909447873e36 100644
--- a/fs/fat/namei_vfat.c
+++ b/fs/fat/namei_vfat.c
@@ -1185,6 +1185,7 @@ static const struct inode_operations vfat_dir_inode_operations = {
 	.rename		= vfat_rename2,
 	.setattr	= fat_setattr,
 	.getattr	= fat_getattr,
+	.fileattr_get	= fat_fileattr_get,
 	.update_time	= fat_update_time,
 };
 
diff --git a/fs/file_attr.c b/fs/file_attr.c
index da983e105d708..bfb00d256dd56 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)
@@ -39,6 +37,8 @@ void fileattr_fill_xflags(struct file_kattr *fa, u32 xflags)
 		fa->flags |= FS_PROJINHERIT_FL;
 	if (fa->fsx_xflags & FS_XFLAG_VERITY)
 		fa->flags |= FS_VERITY_FL;
+	if (fa->fsx_xflags & FS_XFLAG_CASEFOLD)
+		fa->flags |= FS_CASEFOLD_FL;
 }
 EXPORT_SYMBOL(fileattr_fill_xflags);
 
@@ -48,11 +48,9 @@ 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)
@@ -71,6 +69,8 @@ void fileattr_fill_flags(struct file_kattr *fa, u32 flags)
 		fa->fsx_xflags |= FS_XFLAG_PROJINHERIT;
 	if (fa->flags & FS_VERITY_FL)
 		fa->fsx_xflags |= FS_XFLAG_VERITY;
+	if (fa->flags & FS_CASEFOLD_FL)
+		fa->fsx_xflags |= FS_XFLAG_CASEFOLD;
 }
 EXPORT_SYMBOL(fileattr_fill_flags);
 
@@ -325,7 +325,7 @@ 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;
 
@@ -357,7 +357,7 @@ 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);
@@ -431,7 +431,7 @@ SYSCALL_DEFINE5(file_setattr, int, dfd, const char __user *, filename,
 	struct path filepath __free(path_put) = {};
 	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/hfs/dir.c b/fs/hfs/dir.c
index f5e7efe924e78..c4c6e1623f55d 100644
--- a/fs/hfs/dir.c
+++ b/fs/hfs/dir.c
@@ -328,4 +328,5 @@ const struct inode_operations hfs_dir_inode_operations = {
 	.rmdir		= hfs_remove,
 	.rename		= hfs_rename,
 	.setattr	= hfs_inode_setattr,
+	.fileattr_get	= hfs_fileattr_get,
 };
diff --git a/fs/hfs/hfs_fs.h b/fs/hfs/hfs_fs.h
index ac0e83f77a0f1..1b23448c9a48b 100644
--- a/fs/hfs/hfs_fs.h
+++ b/fs/hfs/hfs_fs.h
@@ -177,6 +177,8 @@ extern int hfs_get_block(struct inode *inode, sector_t block,
 extern const struct address_space_operations hfs_aops;
 extern const struct address_space_operations hfs_btree_aops;
 
+struct file_kattr;
+int hfs_fileattr_get(struct dentry *dentry, struct file_kattr *fa);
 int hfs_write_begin(const struct kiocb *iocb, struct address_space *mapping,
 		    loff_t pos, unsigned int len, struct folio **foliop,
 		    void **fsdata);
diff --git a/fs/hfs/inode.c b/fs/hfs/inode.c
index 89b33a9d46d5c..f41cc261684d9 100644
--- a/fs/hfs/inode.c
+++ b/fs/hfs/inode.c
@@ -18,6 +18,7 @@
 #include <linux/uio.h>
 #include <linux/xattr.h>
 #include <linux/blkdev.h>
+#include <linux/fileattr.h>
 
 #include "hfs_fs.h"
 #include "btree.h"
@@ -699,6 +700,18 @@ static int hfs_file_fsync(struct file *filp, loff_t start, loff_t end,
 	return ret;
 }
 
+int hfs_fileattr_get(struct dentry *dentry, struct file_kattr *fa)
+{
+	/*
+	 * HFS compares filenames using Mac OS Roman case folding, so
+	 * lookup is always case-insensitive. Names are stored on disk
+	 * with case intact; CASENONPRESERVING stays clear.
+	 */
+	fa->fsx_xflags |= FS_XFLAG_CASEFOLD;
+	fa->flags |= FS_CASEFOLD_FL;
+	return 0;
+}
+
 static const struct file_operations hfs_file_operations = {
 	.llseek		= generic_file_llseek,
 	.read_iter	= generic_file_read_iter,
@@ -715,4 +728,5 @@ static const struct inode_operations hfs_file_inode_operations = {
 	.lookup		= hfs_file_lookup,
 	.setattr	= hfs_inode_setattr,
 	.listxattr	= generic_listxattr,
+	.fileattr_get	= hfs_fileattr_get,
 };
diff --git a/fs/hfsplus/inode.c b/fs/hfsplus/inode.c
index d05891ec492e3..5565c14b4bf69 100644
--- a/fs/hfsplus/inode.c
+++ b/fs/hfsplus/inode.c
@@ -740,6 +740,7 @@ int hfsplus_fileattr_get(struct dentry *dentry, struct file_kattr *fa)
 {
 	struct inode *inode = d_inode(dentry);
 	struct hfsplus_inode_info *hip = HFSPLUS_I(inode);
+	struct hfsplus_sb_info *sbi = HFSPLUS_SB(inode->i_sb);
 	unsigned int flags = 0;
 
 	if (inode->i_flags & S_IMMUTABLE)
@@ -748,6 +749,8 @@ int hfsplus_fileattr_get(struct dentry *dentry, struct file_kattr *fa)
 		flags |= FS_APPEND_FL;
 	if (hip->userflags & HFSPLUS_FLG_NODUMP)
 		flags |= FS_NODUMP_FL;
+	if (test_bit(HFSPLUS_SB_CASEFOLD, &sbi->flags))
+		flags |= FS_CASEFOLD_FL;
 
 	fileattr_fill_flags(fa, flags);
 
@@ -759,13 +762,24 @@ int hfsplus_fileattr_set(struct mnt_idmap *idmap,
 {
 	struct inode *inode = d_inode(dentry);
 	struct hfsplus_inode_info *hip = HFSPLUS_I(inode);
+	struct hfsplus_sb_info *sbi = HFSPLUS_SB(inode->i_sb);
+	unsigned int allowed = FS_IMMUTABLE_FL | FS_APPEND_FL | FS_NODUMP_FL;
 	unsigned int new_fl = 0;
 
 	if (fileattr_has_fsx(fa))
 		return -EOPNOTSUPP;
 
+	/*
+	 * FS_CASEFOLD_FL reflects HFSPLUS_SB_CASEFOLD, a mount-time
+	 * property. Accept it as a no-op so chattr's RMW round-trip
+	 * succeeds; reject any attempt to enable it on a volume that
+	 * was not formatted case-insensitive.
+	 */
+	if (test_bit(HFSPLUS_SB_CASEFOLD, &sbi->flags))
+		allowed |= FS_CASEFOLD_FL;
+
 	/* don't silently ignore unsupported ext2 flags */
-	if (fa->flags & ~(FS_IMMUTABLE_FL|FS_APPEND_FL|FS_NODUMP_FL))
+	if (fa->flags & ~allowed)
 		return -EOPNOTSUPP;
 
 	if (fa->flags & FS_IMMUTABLE_FL)
diff --git a/fs/isofs/dir.c b/fs/isofs/dir.c
index 2fd9948d606e9..55385a72a4ce0 100644
--- a/fs/isofs/dir.c
+++ b/fs/isofs/dir.c
@@ -14,6 +14,7 @@
 #include <linux/gfp.h>
 #include <linux/filelock.h>
 #include "isofs.h"
+#include <linux/fileattr.h>
 
 int isofs_name_translate(struct iso_directory_record *de, char *new, struct inode *inode)
 {
@@ -267,6 +268,20 @@ static int isofs_readdir(struct file *file, struct dir_context *ctx)
 	return result;
 }
 
+int isofs_fileattr_get(struct dentry *dentry, struct file_kattr *fa)
+{
+	struct isofs_sb_info *sbi = ISOFS_SB(dentry->d_sb);
+
+	if (sbi->s_check == 'r') {
+		fa->fsx_xflags |= FS_XFLAG_CASEFOLD;
+		fa->flags |= FS_CASEFOLD_FL;
+	}
+	if (!sbi->s_joliet_level && !sbi->s_rock &&
+	    (sbi->s_mapping == 'n' || sbi->s_mapping == 'a'))
+		fa->fsx_xflags |= FS_XFLAG_CASENONPRESERVING;
+	return 0;
+}
+
 const struct file_operations isofs_dir_operations =
 {
 	.llseek = generic_file_llseek,
@@ -281,6 +296,7 @@ const struct file_operations isofs_dir_operations =
 const struct inode_operations isofs_dir_inode_operations =
 {
 	.lookup = isofs_lookup,
+	.fileattr_get = isofs_fileattr_get,
 };
 
 
diff --git a/fs/isofs/isofs.h b/fs/isofs/isofs.h
index 5065558375333..0ec8b24a42edc 100644
--- a/fs/isofs/isofs.h
+++ b/fs/isofs/isofs.h
@@ -197,6 +197,9 @@ isofs_normalize_block_and_offset(struct iso_directory_record* de,
 	}
 }
 
+struct file_kattr;
+int isofs_fileattr_get(struct dentry *dentry, struct file_kattr *fa);
+
 extern const struct inode_operations isofs_dir_inode_operations;
 extern const struct file_operations isofs_dir_operations;
 extern const struct address_space_operations isofs_symlink_aops;
diff --git a/fs/nfs/client.c b/fs/nfs/client.c
index be02bb227741d..73b95318ba48b 100644
--- a/fs/nfs/client.c
+++ b/fs/nfs/client.c
@@ -914,6 +914,7 @@ static void nfs_server_set_fsinfo(struct nfs_server *server,
  */
 static int nfs_probe_fsinfo(struct nfs_server *server, struct nfs_fh *mntfh, struct nfs_fattr *fattr)
 {
+	struct nfs_pathconf pathinfo = { };
 	struct nfs_fsinfo fsinfo;
 	struct nfs_client *clp = server->nfs_client;
 	int error;
@@ -933,15 +934,28 @@ static int nfs_probe_fsinfo(struct nfs_server *server, struct nfs_fh *mntfh, str
 
 	nfs_server_set_fsinfo(server, &fsinfo);
 
-	/* Get some general file system info */
-	if (server->namelen == 0) {
-		struct nfs_pathconf pathinfo;
+	pathinfo.fattr = fattr;
+	nfs_fattr_init(fattr);
 
-		pathinfo.fattr = fattr;
-		nfs_fattr_init(fattr);
+	if (clp->rpc_ops->version < 4 || server->namelen == 0) {
+		if (clp->rpc_ops->pathconf(server, mntfh, &pathinfo) >= 0) {
+			if (server->namelen == 0)
+				server->namelen = pathinfo.max_namelen;
+			if (clp->rpc_ops->version < 4) {
+				unsigned int caps = server->caps;
 
-		if (clp->rpc_ops->pathconf(server, mntfh, &pathinfo) >= 0)
-			server->namelen = pathinfo.max_namelen;
+				caps &= ~(NFS_CAP_CASE_INSENSITIVE |
+					  NFS_CAP_CASE_NONPRESERVING);
+				if (pathinfo.case_insensitive)
+					caps |= NFS_CAP_CASE_INSENSITIVE;
+				if (!pathinfo.case_preserving)
+					caps |= NFS_CAP_CASE_NONPRESERVING;
+				server->caps = caps;
+			}
+		} else if (clp->rpc_ops->version < 4) {
+			server->caps &= ~(NFS_CAP_CASE_INSENSITIVE |
+					  NFS_CAP_CASE_NONPRESERVING);
+		}
 	}
 
 	if (clp->rpc_ops->discover_trunking != NULL &&
diff --git a/fs/nfs/inode.c b/fs/nfs/inode.c
index cd9930dee00e2..6227df9ae6f1d 100644
--- a/fs/nfs/inode.c
+++ b/fs/nfs/inode.c
@@ -41,6 +41,7 @@
 #include <linux/freezer.h>
 #include <linux/uaccess.h>
 #include <linux/iversion.h>
+#include <linux/fileattr.h>
 
 #include "nfs4_fs.h"
 #include "callback.h"
@@ -1095,6 +1096,20 @@ out:
 }
 EXPORT_SYMBOL_GPL(nfs_getattr);
 
+int nfs_fileattr_get(struct dentry *dentry, struct file_kattr *fa)
+{
+	struct inode *inode = d_inode(dentry);
+
+	if (nfs_server_capable(inode, NFS_CAP_CASE_INSENSITIVE)) {
+		fa->fsx_xflags |= FS_XFLAG_CASEFOLD;
+		fa->flags |= FS_CASEFOLD_FL;
+	}
+	if (nfs_server_capable(inode, NFS_CAP_CASE_NONPRESERVING))
+		fa->fsx_xflags |= FS_XFLAG_CASENONPRESERVING;
+	return 0;
+}
+EXPORT_SYMBOL_GPL(nfs_fileattr_get);
+
 static void nfs_init_lock_context(struct nfs_lock_context *l_ctx)
 {
 	refcount_set(&l_ctx->count, 1);
diff --git a/fs/nfs/internal.h b/fs/nfs/internal.h
index 18d46b0e71ddc..ec2b3d9843989 100644
--- a/fs/nfs/internal.h
+++ b/fs/nfs/internal.h
@@ -451,6 +451,9 @@ extern void nfs_set_cache_invalid(struct inode *inode, unsigned long flags);
 extern bool nfs_check_cache_invalid(struct inode *, unsigned long);
 extern int nfs_wait_bit_killable(struct wait_bit_key *key, int mode);
 
+struct file_kattr;
+int nfs_fileattr_get(struct dentry *dentry, struct file_kattr *fa);
+
 #if IS_ENABLED(CONFIG_NFS_LOCALIO)
 /* localio.c */
 struct nfs_local_dio {
diff --git a/fs/nfs/namespace.c b/fs/nfs/namespace.c
index af9be0c5f5163..6d0073c24771b 100644
--- a/fs/nfs/namespace.c
+++ b/fs/nfs/namespace.c
@@ -246,11 +246,13 @@ nfs_namespace_setattr(struct mnt_idmap *idmap, struct dentry *dentry,
 const struct inode_operations nfs_mountpoint_inode_operations = {
 	.getattr	= nfs_getattr,
 	.setattr	= nfs_setattr,
+	.fileattr_get	= nfs_fileattr_get,
 };
 
 const struct inode_operations nfs_referral_inode_operations = {
 	.getattr	= nfs_namespace_getattr,
 	.setattr	= nfs_namespace_setattr,
+	.fileattr_get	= nfs_fileattr_get,
 };
 
 static void nfs_expire_automounts(struct work_struct *work)
diff --git a/fs/nfs/nfs3proc.c b/fs/nfs/nfs3proc.c
index 95d7cd564b746..b80d0c5efc279 100644
--- a/fs/nfs/nfs3proc.c
+++ b/fs/nfs/nfs3proc.c
@@ -1053,6 +1053,7 @@ static const struct inode_operations nfs3_dir_inode_operations = {
 	.permission	= nfs_permission,
 	.getattr	= nfs_getattr,
 	.setattr	= nfs_setattr,
+	.fileattr_get	= nfs_fileattr_get,
 #ifdef CONFIG_NFS_V3_ACL
 	.listxattr	= nfs3_listxattr,
 	.get_inode_acl	= nfs3_get_acl,
@@ -1064,6 +1065,7 @@ static const struct inode_operations nfs3_file_inode_operations = {
 	.permission	= nfs_permission,
 	.getattr	= nfs_getattr,
 	.setattr	= nfs_setattr,
+	.fileattr_get	= nfs_fileattr_get,
 #ifdef CONFIG_NFS_V3_ACL
 	.listxattr	= nfs3_listxattr,
 	.get_inode_acl	= nfs3_get_acl,
diff --git a/fs/nfs/nfs3xdr.c b/fs/nfs/nfs3xdr.c
index e17d729084125..e745e78faab0a 100644
--- a/fs/nfs/nfs3xdr.c
+++ b/fs/nfs/nfs3xdr.c
@@ -2276,8 +2276,11 @@ static int decode_pathconf3resok(struct xdr_stream *xdr,
 	if (unlikely(!p))
 		return -EIO;
 	result->max_link = be32_to_cpup(p++);
-	result->max_namelen = be32_to_cpup(p);
-	/* ignore remaining fields */
+	result->max_namelen = be32_to_cpup(p++);
+	p++;	/* ignore no_trunc */
+	p++;	/* ignore chown_restricted */
+	result->case_insensitive = be32_to_cpup(p++) != 0;
+	result->case_preserving = be32_to_cpup(p) != 0;
 	return 0;
 }
 
diff --git a/fs/nfs/nfs4proc.c b/fs/nfs/nfs4proc.c
index a9b8d482d2894..0715a6745d1fa 100644
--- a/fs/nfs/nfs4proc.c
+++ b/fs/nfs/nfs4proc.c
@@ -3933,7 +3933,8 @@ static int _nfs4_server_capabilities(struct nfs_server *server, struct nfs_fh *f
 		server->caps &=
 			~(NFS_CAP_ACLS | NFS_CAP_HARDLINKS | NFS_CAP_SYMLINKS |
 			  NFS_CAP_SECURITY_LABEL | NFS_CAP_FS_LOCATIONS |
-			  NFS_CAP_OPEN_XOR | NFS_CAP_DELEGTIME);
+			  NFS_CAP_OPEN_XOR | NFS_CAP_DELEGTIME |
+			  NFS_CAP_CASE_INSENSITIVE | NFS_CAP_CASE_NONPRESERVING);
 		server->fattr_valid = NFS_ATTR_FATTR_V4;
 		if (res.attr_bitmask[0] & FATTR4_WORD0_ACL &&
 				res.acl_bitmask & ACL4_SUPPORT_ALLOW_ACL)
@@ -3944,8 +3945,9 @@ static int _nfs4_server_capabilities(struct nfs_server *server, struct nfs_fh *f
 			server->caps |= NFS_CAP_SYMLINKS;
 		if (res.case_insensitive)
 			server->caps |= NFS_CAP_CASE_INSENSITIVE;
-		if (res.case_preserving)
-			server->caps |= NFS_CAP_CASE_PRESERVING;
+		if ((res.attr_bitmask[0] & FATTR4_WORD0_CASE_PRESERVING) &&
+		    !res.case_preserving)
+			server->caps |= NFS_CAP_CASE_NONPRESERVING;
 #ifdef CONFIG_NFS_V4_SECURITY_LABEL
 		if (res.attr_bitmask[2] & FATTR4_WORD2_SECURITY_LABEL)
 			server->caps |= NFS_CAP_SECURITY_LABEL;
@@ -10617,6 +10619,7 @@ static const struct inode_operations nfs4_dir_inode_operations = {
 	.getattr	= nfs_getattr,
 	.setattr	= nfs_setattr,
 	.listxattr	= nfs4_listxattr,
+	.fileattr_get	= nfs_fileattr_get,
 };
 
 static const struct inode_operations nfs4_file_inode_operations = {
@@ -10624,6 +10627,7 @@ static const struct inode_operations nfs4_file_inode_operations = {
 	.getattr	= nfs_getattr,
 	.setattr	= nfs_setattr,
 	.listxattr	= nfs4_listxattr,
+	.fileattr_get	= nfs_fileattr_get,
 };
 
 static struct nfs_server *nfs4_clone_server(struct nfs_server *source,
diff --git a/fs/nfs/proc.c b/fs/nfs/proc.c
index 70795684b8e84..03c2c1f31be9a 100644
--- a/fs/nfs/proc.c
+++ b/fs/nfs/proc.c
@@ -598,6 +598,7 @@ nfs_proc_pathconf(struct nfs_server *server, struct nfs_fh *fhandle,
 {
 	info->max_link = 0;
 	info->max_namelen = NFS2_MAXNAMLEN;
+	info->case_preserving = true;
 	return 0;
 }
 
@@ -718,12 +719,14 @@ static const struct inode_operations nfs_dir_inode_operations = {
 	.permission	= nfs_permission,
 	.getattr	= nfs_getattr,
 	.setattr	= nfs_setattr,
+	.fileattr_get	= nfs_fileattr_get,
 };
 
 static const struct inode_operations nfs_file_inode_operations = {
 	.permission	= nfs_permission,
 	.getattr	= nfs_getattr,
 	.setattr	= nfs_setattr,
+	.fileattr_get	= nfs_fileattr_get,
 };
 
 const struct nfs_rpc_ops nfs_v2_clientops = {
diff --git a/fs/nfs/symlink.c b/fs/nfs/symlink.c
index 58146e9354020..74a072896f8d9 100644
--- a/fs/nfs/symlink.c
+++ b/fs/nfs/symlink.c
@@ -22,6 +22,8 @@
 #include <linux/mm.h>
 #include <linux/string.h>
 
+#include "internal.h"
+
 /* Symlink caching in the page cache is even more simplistic
  * and straight-forward than readdir caching.
  */
@@ -74,4 +76,5 @@ const struct inode_operations nfs_symlink_inode_operations = {
 	.get_link	= nfs_get_link,
 	.getattr	= nfs_getattr,
 	.setattr	= nfs_setattr,
+	.fileattr_get	= nfs_fileattr_get,
 };
diff --git a/fs/nfsd/nfs3proc.c b/fs/nfsd/nfs3proc.c
index 42adc5461db03..aeda7a802bdf7 100644
--- a/fs/nfsd/nfs3proc.c
+++ b/fs/nfsd/nfs3proc.c
@@ -710,23 +710,46 @@ nfsd3_proc_pathconf(struct svc_rqst *rqstp)
 	resp->p_name_max = 255;		/* at least */
 	resp->p_no_trunc = 0;
 	resp->p_chown_restricted = 1;
-	resp->p_case_insensitive = 0;
-	resp->p_case_preserving = 1;
+	resp->p_case_insensitive = false;
+	resp->p_case_preserving = true;
 
 	resp->status = fh_verify(rqstp, &argp->fh, 0, NFSD_MAY_NOP);
 
 	if (resp->status == nfs_ok) {
 		struct super_block *sb = argp->fh.fh_dentry->d_sb;
+		int err;
 
-		/* Note that we don't care for remote fs's here */
-		switch (sb->s_magic) {
-		case EXT2_SUPER_MAGIC:
+		if (sb->s_magic == EXT2_SUPER_MAGIC) {
 			resp->p_link_max = EXT2_LINK_MAX;
 			resp->p_name_max = EXT2_NAME_LEN;
+		}
+
+		err = nfsd_get_case_info(argp->fh.fh_dentry,
+					 &resp->p_case_insensitive,
+					 &resp->p_case_preserving);
+		/*
+		 * RFC 1813 lists NFS3ERR_STALE, NFS3ERR_BADHANDLE, and
+		 * NFS3ERR_SERVERFAULT as the only PATHCONF errors.
+		 */
+		switch (err) {
+		case 0:
+		case -EOPNOTSUPP:
+			/* Both arms leave the output booleans valid. */
+			break;
+		case -EACCES:
+		case -EPERM:
+			/*
+			 * Policy denied the query. Report STALE so the
+			 * handle is unusable without implying a server
+			 * malfunction.
+			 */
+			resp->status = nfserr_stale;
+			break;
+		case -ESTALE:
+			resp->status = nfserr_stale;
 			break;
-		case MSDOS_SUPER_MAGIC:
-			resp->p_case_insensitive = 1;
-			resp->p_case_preserving  = 0;
+		default:
+			resp->status = nfserr_serverfault;
 			break;
 		}
 	}
diff --git a/fs/nfsd/nfs4xdr.c b/fs/nfsd/nfs4xdr.c
index 2a0946c630e1d..20355dc3f1d16 100644
--- a/fs/nfsd/nfs4xdr.c
+++ b/fs/nfsd/nfs4xdr.c
@@ -3158,6 +3158,8 @@ struct nfsd4_fattr_args {
 	u32			rdattr_err;
 	bool			contextsupport;
 	bool			ignore_crossmnt;
+	bool			case_insensitive;
+	bool			case_preserving;
 };
 
 typedef __be32(*nfsd4_enc_attr)(struct xdr_stream *xdr,
@@ -3356,6 +3358,33 @@ static __be32 nfsd4_encode_fattr4_acl(struct xdr_stream *xdr,
 	return nfs_ok;
 }
 
+static __be32 nfsd4_encode_fattr4_case_insensitive(struct xdr_stream *xdr,
+					const struct nfsd4_fattr_args *args)
+{
+	return nfsd4_encode_bool(xdr, args->case_insensitive);
+}
+
+static __be32 nfsd4_encode_fattr4_case_preserving(struct xdr_stream *xdr,
+					const struct nfsd4_fattr_args *args)
+{
+	return nfsd4_encode_bool(xdr, args->case_preserving);
+}
+
+static __be32 nfsd4_encode_fattr4_homogeneous(struct xdr_stream *xdr,
+					const struct nfsd4_fattr_args *args)
+{
+	/*
+	 * Casefold-capable filesystems (e.g. ext4 or f2fs with the
+	 * casefold feature) attach a Unicode encoding at mount time
+	 * but apply case folding per directory.  The per-file-system
+	 * case_insensitive and case_preserving values can therefore
+	 * legitimately differ across objects that share the same fsid.
+	 * Report FATTR4_HOMOGENEOUS = FALSE on such filesystems to
+	 * keep that variation consistent with RFC 8881 Section 5.8.2.16.
+	 */
+	return nfsd4_encode_bool(xdr, !sb_has_encoding(args->dentry->d_sb));
+}
+
 static __be32 nfsd4_encode_fattr4_filehandle(struct xdr_stream *xdr,
 					     const struct nfsd4_fattr_args *args)
 {
@@ -3748,8 +3777,8 @@ static const nfsd4_enc_attr nfsd4_enc_fattr4_encode_ops[] = {
 	[FATTR4_ACLSUPPORT]		= nfsd4_encode_fattr4_aclsupport,
 	[FATTR4_ARCHIVE]		= nfsd4_encode_fattr4__noop,
 	[FATTR4_CANSETTIME]		= nfsd4_encode_fattr4__true,
-	[FATTR4_CASE_INSENSITIVE]	= nfsd4_encode_fattr4__false,
-	[FATTR4_CASE_PRESERVING]	= nfsd4_encode_fattr4__true,
+	[FATTR4_CASE_INSENSITIVE]	= nfsd4_encode_fattr4_case_insensitive,
+	[FATTR4_CASE_PRESERVING]	= nfsd4_encode_fattr4_case_preserving,
 	[FATTR4_CHOWN_RESTRICTED]	= nfsd4_encode_fattr4__true,
 	[FATTR4_FILEHANDLE]		= nfsd4_encode_fattr4_filehandle,
 	[FATTR4_FILEID]			= nfsd4_encode_fattr4_fileid,
@@ -3758,7 +3787,7 @@ static const nfsd4_enc_attr nfsd4_enc_fattr4_encode_ops[] = {
 	[FATTR4_FILES_TOTAL]		= nfsd4_encode_fattr4_files_total,
 	[FATTR4_FS_LOCATIONS]		= nfsd4_encode_fattr4_fs_locations,
 	[FATTR4_HIDDEN]			= nfsd4_encode_fattr4__noop,
-	[FATTR4_HOMOGENEOUS]		= nfsd4_encode_fattr4__true,
+	[FATTR4_HOMOGENEOUS]		= nfsd4_encode_fattr4_homogeneous,
 	[FATTR4_MAXFILESIZE]		= nfsd4_encode_fattr4_maxfilesize,
 	[FATTR4_MAXLINK]		= nfsd4_encode_fattr4_maxlink,
 	[FATTR4_MAXNAME]		= nfsd4_encode_fattr4_maxname,
@@ -3854,13 +3883,16 @@ static const nfsd4_enc_attr nfsd4_enc_fattr4_encode_ops[] = {
 
 /*
  * Note: @fhp can be NULL; in this case, we might have to compose the filehandle
- * ourselves.
+ * ourselves. @case_cache is NULL for callers that encode a single dentry
+ * (GETATTR, the buffer wrapper); READDIR passes a per-request cache so
+ * non-directory children share the parent's case-folding probe result.
  */
 static __be32
 nfsd4_encode_fattr4(struct svc_rqst *rqstp, struct xdr_stream *xdr,
 		    struct svc_fh *fhp, struct svc_export *exp,
 		    struct dentry *dentry, const u32 *bmval,
-		    int ignore_crossmnt)
+		    int ignore_crossmnt,
+		    struct nfsd_case_attrs_cache *case_cache)
 {
 	DECLARE_BITMAP(attr_bitmap, ARRAY_SIZE(nfsd4_enc_fattr4_encode_ops));
 	struct nfs4_delegation *dp = NULL;
@@ -3968,6 +4000,47 @@ nfsd4_encode_fattr4(struct svc_rqst *rqstp, struct xdr_stream *xdr,
 		args.fhp = tempfh;
 	} else
 		args.fhp = fhp;
+	if (attrmask[0] & (FATTR4_WORD0_CASE_INSENSITIVE |
+			   FATTR4_WORD0_CASE_PRESERVING)) {
+		/*
+		 * In a batched encoder (READDIR) every non-directory
+		 * child shares the same case-folding answer, so the
+		 * directory being read is probed once and the result is
+		 * cached. The probe targets case_cache->dir, the held
+		 * readdir filehandle's dentry, instead of the child's
+		 * locklessly-acquired dentry, which a concurrent rename
+		 * could move under an unrelated parent. Directory
+		 * entries are queried directly because casefold-capable
+		 * filesystems answer per directory.
+		 *
+		 * Per RFC 8881 Section 18.7.3, an attribute advertised
+		 * in SUPPORTED_ATTRS must come back with a value or the
+		 * GETATTR must fail. nfsd_get_case_info() fills POSIX
+		 * defaults and returns -EOPNOTSUPP when the underlying
+		 * filesystem does not expose case state; encode those
+		 * defaults so the reply agrees with what SUPPORTED_ATTRS
+		 * advertises. Other errors fail the operation as the
+		 * spec requires.
+		 */
+		if (case_cache && !d_is_dir(dentry)) {
+			if (!case_cache->valid) {
+				err = nfsd_get_case_info(case_cache->dir,
+							 &case_cache->insensitive,
+							 &case_cache->preserving);
+				if (err && err != -EOPNOTSUPP)
+					goto out_nfserr;
+				case_cache->valid = true;
+			}
+			args.case_insensitive = case_cache->insensitive;
+			args.case_preserving = case_cache->preserving;
+		} else {
+			err = nfsd_get_case_info(dentry,
+						 &args.case_insensitive,
+						 &args.case_preserving);
+			if (err && err != -EOPNOTSUPP)
+				goto out_nfserr;
+		}
+	}
 
 	if (attrmask[0] & FATTR4_WORD0_ACL) {
 		err = nfsd4_get_nfs4_acl(rqstp, dentry, &args.acl);
@@ -4124,7 +4197,7 @@ __be32 nfsd4_encode_fattr_to_buf(__be32 **p, int words,
 
 	svcxdr_init_encode_from_buffer(&xdr, &dummy, *p, words << 2);
 	ret = nfsd4_encode_fattr4(rqstp, &xdr, fhp, exp, dentry, bmval,
-				  ignore_crossmnt);
+				  ignore_crossmnt, NULL);
 	*p = xdr.p;
 	return ret;
 }
@@ -4162,6 +4235,7 @@ nfsd4_encode_entry4_fattr(struct nfsd4_readdir *cd, const char *name,
 	struct dentry *dentry;
 	__be32 nfserr;
 	int ignore_crossmnt = 0;
+	bool crossed = false;
 
 	dentry = lookup_one_positive_unlocked(&nop_mnt_idmap,
 					      &QSTR_LEN(name, namlen),
@@ -4198,11 +4272,18 @@ nfsd4_encode_entry4_fattr(struct nfsd4_readdir *cd, const char *name,
 		nfserr = check_nfsd_access(exp, cd->rd_rqstp, false);
 		if (nfserr)
 			goto out_put;
+		crossed = true;
 
 	}
 out_encode:
+	/*
+	 * A crossed entry no longer shares a parent with the directory
+	 * being read, so it must neither consume nor populate the
+	 * per-readdir case-folding cache.
+	 */
 	nfserr = nfsd4_encode_fattr4(cd->rd_rqstp, cd->xdr, NULL, exp, dentry,
-				     cd->rd_bmval, ignore_crossmnt);
+				     cd->rd_bmval, ignore_crossmnt,
+				     crossed ? NULL : &cd->rd_case_cache);
 out_put:
 	dput(dentry);
 	exp_put(exp);
@@ -4449,7 +4530,7 @@ nfsd4_encode_getattr(struct nfsd4_compoundres *resp, __be32 nfserr,
 
 	/* obj_attributes */
 	return nfsd4_encode_fattr4(resp->rqstp, xdr, fhp, fhp->fh_export,
-				   fhp->fh_dentry, getattr->ga_bmval, 0);
+				   fhp->fh_dentry, getattr->ga_bmval, 0, NULL);
 }
 
 static __be32
@@ -4976,6 +5057,8 @@ static __be32 nfsd4_encode_dirlist4(struct xdr_stream *xdr,
 	readdir->rd_maxcount = maxcount;
 	readdir->common.err = 0;
 	readdir->cookie_offset = 0;
+	readdir->rd_case_cache.dir = readdir->rd_fhp->fh_dentry;
+	readdir->rd_case_cache.valid = false;
 	offset = readdir->rd_cookie;
 	status = nfsd_readdir(readdir->rd_rqstp, readdir->rd_fhp, &offset,
 			      &readdir->common, nfsd4_encode_entry4);
diff --git a/fs/nfsd/vfs.c b/fs/nfsd/vfs.c
index eafdf7b7890fd..ba97e287c0072 100644
--- a/fs/nfsd/vfs.c
+++ b/fs/nfsd/vfs.c
@@ -32,6 +32,7 @@
 #include <linux/writeback.h>
 #include <linux/security.h>
 #include <linux/sunrpc/xdr.h>
+#include <linux/fileattr.h>
 
 #include "xdr3.h"
 
@@ -2891,3 +2892,88 @@ nfsd_permission(struct svc_cred *cred, struct svc_export *exp,
 
 	return err? nfserrno(err) : 0;
 }
+
+/**
+ * nfsd_get_case_info - get case sensitivity info for a dentry
+ * @dentry: dentry to query
+ * @case_insensitive: set to true if name comparison ignores case
+ * @case_preserving: set to true if case is preserved on disk
+ *
+ * On casefold-capable filesystems the flag lives on the directory,
+ * not on its entries, so for a non-directory @dentry the parent is
+ * queried instead. A directory (including an export root, whose
+ * parent lies outside the export) is queried as-is so its own
+ * contents' lookup behavior is reported. NFSD advertises
+ * fattr4_homogeneous as FALSE, so per-directory answers may differ
+ * within an export.
+ *
+ * The probe runs with kernel credentials. case_insensitive and
+ * case_preserving describe the directory's structural lookup
+ * behavior, not the caller's identity; running under the calling
+ * client's mapped credentials would let per-client MAC policy on
+ * the parent directory turn this query into NFS4ERR_ACCESS even
+ * though the underlying property is the same for every client.
+ *
+ * When the filesystem does not expose case-folding state (no
+ * ->fileattr_get, or the callback returns -EOPNOTSUPP /
+ * -ENOIOCTLCMD / -ENOTTY / -EINVAL), the outputs are filled with
+ * POSIX defaults (case-sensitive, case-preserving) on the premise
+ * that a filesystem with case-folding support wires up
+ * fileattr_get.
+ *
+ * Return: 0 with outputs filled, -EOPNOTSUPP with outputs filled
+ *         to POSIX defaults, or a negative errno (e.g., -EIO,
+ *         -ESTALE, -ENOMEM) with outputs unmodified.
+ */
+int
+nfsd_get_case_info(struct dentry *dentry, bool *case_insensitive,
+		   bool *case_preserving)
+{
+	struct file_kattr fa = {};
+	const struct cred *saved;
+	struct cred *probe;
+	struct dentry *cd;
+	bool put = false;
+	int err;
+
+	if (d_is_dir(dentry)) {
+		cd = dentry;
+	} else {
+		cd = dget_parent(dentry);
+		put = true;
+	}
+
+	probe = prepare_kernel_cred(&init_task);
+	if (!probe) {
+		err = -ENOMEM;
+		goto out;
+	}
+	saved = override_creds(probe);
+
+	err = vfs_fileattr_get(cd, &fa);
+
+	put_cred(revert_creds(saved));
+out:
+	if (put)
+		dput(cd);
+	switch (err) {
+	case 0:
+		*case_insensitive = fa.fsx_xflags & FS_XFLAG_CASEFOLD;
+		*case_preserving =
+			!(fa.fsx_xflags & FS_XFLAG_CASENONPRESERVING);
+		return 0;
+	case -EINVAL:
+	case -ENOTTY:
+	case -ENOIOCTLCMD:
+	case -EOPNOTSUPP:
+		/*
+		 * Filesystem does not expose case state.
+		 * Report POSIX defaults.
+		 */
+		*case_insensitive = false;
+		*case_preserving = true;
+		return -EOPNOTSUPP;
+	default:
+		return err;
+	}
+}
diff --git a/fs/nfsd/vfs.h b/fs/nfsd/vfs.h
index 702a844f2106b..e09ea04a51b99 100644
--- a/fs/nfsd/vfs.h
+++ b/fs/nfsd/vfs.h
@@ -156,6 +156,9 @@ __be32		nfsd_readdir(struct svc_rqst *, struct svc_fh *,
 			     loff_t *, struct readdir_cd *, nfsd_filldir_t);
 __be32		nfsd_statfs(struct svc_rqst *, struct svc_fh *,
 				struct kstatfs *, int access);
+int		nfsd_get_case_info(struct dentry *dentry,
+				   bool *case_insensitive,
+				   bool *case_preserving);
 
 __be32		nfsd_permission(struct svc_cred *cred, struct svc_export *exp,
 				struct dentry *dentry, int acc);
diff --git a/fs/nfsd/xdr3.h b/fs/nfsd/xdr3.h
index 522067b7fd755..a7c9714b0b0e1 100644
--- a/fs/nfsd/xdr3.h
+++ b/fs/nfsd/xdr3.h
@@ -209,8 +209,8 @@ struct nfsd3_pathconfres {
 	__u32			p_name_max;
 	__u32			p_no_trunc;
 	__u32			p_chown_restricted;
-	__u32			p_case_insensitive;
-	__u32			p_case_preserving;
+	bool			p_case_insensitive;
+	bool			p_case_preserving;
 };
 
 struct nfsd3_commitres {
diff --git a/fs/nfsd/xdr4.h b/fs/nfsd/xdr4.h
index 417e9ad9fbb39..615797df218fd 100644
--- a/fs/nfsd/xdr4.h
+++ b/fs/nfsd/xdr4.h
@@ -432,6 +432,19 @@ struct nfsd4_read {
 	u32			rd_eof;             /* response */
 };
 
+/*
+ * Cache the case-folding properties of @dir so a batched encoder
+ * (e.g., READDIR) does not re-probe per child. @dir is the
+ * directory being read, held by the request, so it is stable
+ * against rename for the duration of the cache's lifetime.
+ */
+struct nfsd_case_attrs_cache {
+	struct dentry	*dir;
+	bool		valid;
+	bool		insensitive;
+	bool		preserving;
+};
+
 struct nfsd4_readdir {
 	u64		rd_cookie;          /* request */
 	nfs4_verifier	rd_verf;            /* request */
@@ -444,6 +457,7 @@ struct nfsd4_readdir {
 	struct readdir_cd	common;
 	struct xdr_stream	*xdr;
 	int			cookie_offset;
+	struct nfsd_case_attrs_cache rd_case_cache;
 };
 
 struct nfsd4_release_lockowner {
diff --git a/fs/ntfs3/file.c b/fs/ntfs3/file.c
index b041639ab406f..ad9350d7fc3fd 100644
--- a/fs/ntfs3/file.c
+++ b/fs/ntfs3/file.c
@@ -181,6 +181,34 @@ 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 (the default). Case sensitivity depends on
+	 * mount options: with "nocase", NTFS is case-insensitive;
+	 * otherwise it is case-sensitive.
+	 */
+	if (sbi->options->nocase) {
+		fa->fsx_xflags |= FS_XFLAG_CASEFOLD;
+		fa->flags |= FS_CASEFOLD_FL;
+	}
+	if (inode->i_flags & S_IMMUTABLE) {
+		fa->fsx_xflags |= FS_XFLAG_IMMUTABLE;
+		fa->flags |= FS_IMMUTABLE_FL;
+	}
+	return 0;
+}
+
+/*
  * ntfs_getattr - inode_operations::getattr
  */
 int ntfs_getattr(struct mnt_idmap *idmap, const struct path *path,
@@ -1547,6 +1575,7 @@ 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/namei.c b/fs/ntfs3/namei.c
index b2af8f695e60f..e159ba66a34a4 100644
--- a/fs/ntfs3/namei.c
+++ b/fs/ntfs3/namei.c
@@ -518,6 +518,7 @@ 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 = {
diff --git a/fs/ntfs3/ntfs_fs.h b/fs/ntfs3/ntfs_fs.h
index bbf3b6a1dcbee..41db22d652c47 100644
--- a/fs/ntfs3/ntfs_fs.h
+++ b/fs/ntfs3/ntfs_fs.h
@@ -529,6 +529,7 @@ bool dir_is_empty(struct inode *dir);
 extern const struct file_operations ntfs_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,
diff --git a/fs/smb/client/cifsfs.c b/fs/smb/client/cifsfs.c
index feac491c50702..192b3f9c7c94a 100644
--- a/fs/smb/client/cifsfs.c
+++ b/fs/smb/client/cifsfs.c
@@ -30,6 +30,7 @@
 #include <linux/xattr.h>
 #include <linux/mm.h>
 #include <linux/key-type.h>
+#include <linux/fileattr.h>
 #include <uapi/linux/magic.h>
 #include <net/ipv6.h>
 #include "cifsfs.h"
@@ -1163,6 +1164,56 @@ struct file_system_type smb3_fs_type = {
 MODULE_ALIAS_FS("smb3");
 MODULE_ALIAS("smb3");
 
+int cifs_fileattr_get(struct dentry *dentry, struct file_kattr *fa)
+{
+	struct cifs_sb_info *cifs_sb = CIFS_SB(dentry->d_sb);
+	struct cifs_tcon *tcon = cifs_sb_master_tcon(cifs_sb);
+	struct inode *inode = d_inode(dentry);
+	u32 attrs;
+
+	/* Preserve FS_COMPR_FL previously reported by cifs_ioctl(). */
+	if (CIFS_I(inode)->cifsAttrs & ATTR_COMPRESSED)
+		fa->flags |= FS_COMPR_FL;
+
+	/*
+	 * FS_CASEFOLD_FL is defined by UAPI as a folder attribute,
+	 * and userspace tools (e.g., lsattr) display it only on
+	 * directories. Confine the case-handling bits to directories
+	 * to match that convention; for non-directories the share's
+	 * case semantics are still discoverable through the parent.
+	 */
+	if (!S_ISDIR(inode->i_mode))
+		return 0;
+
+	/*
+	 * The server's FS_ATTRIBUTE_INFORMATION response, cached on
+	 * the tcon at mount, reflects the share's case-handling
+	 * semantics after any POSIX extensions negotiation. Prefer
+	 * it over the client-local nocase mount option, which only
+	 * governs dentry comparison on this superblock.
+	 *
+	 * QueryFSInfo is best-effort at mount; when it did not
+	 * populate fsAttrInfo, MaxPathNameComponentLength remains
+	 * zero. In that case fall back to nocase so the reporting
+	 * matches the comparison behavior installed on the sb.
+	 */
+	if (le32_to_cpu(tcon->fsAttrInfo.MaxPathNameComponentLength) == 0) {
+		if (tcon->nocase) {
+			fa->fsx_xflags |= FS_XFLAG_CASEFOLD;
+			fa->flags |= FS_CASEFOLD_FL;
+		}
+		return 0;
+	}
+	attrs = le32_to_cpu(tcon->fsAttrInfo.Attributes);
+	if (!(attrs & FILE_CASE_SENSITIVE_SEARCH)) {
+		fa->fsx_xflags |= FS_XFLAG_CASEFOLD;
+		fa->flags |= FS_CASEFOLD_FL;
+	}
+	if (!(attrs & FILE_CASE_PRESERVED_NAMES))
+		fa->fsx_xflags |= FS_XFLAG_CASENONPRESERVING;
+	return 0;
+}
+
 const struct inode_operations cifs_dir_inode_ops = {
 	.create = cifs_create,
 	.atomic_open = cifs_atomic_open,
@@ -1181,6 +1232,7 @@ const struct inode_operations cifs_dir_inode_ops = {
 	.listxattr = cifs_listxattr,
 	.get_acl = cifs_get_acl,
 	.set_acl = cifs_set_acl,
+	.fileattr_get = cifs_fileattr_get,
 };
 
 const struct inode_operations cifs_file_inode_ops = {
@@ -1191,6 +1243,7 @@ const struct inode_operations cifs_file_inode_ops = {
 	.fiemap = cifs_fiemap,
 	.get_acl = cifs_get_acl,
 	.set_acl = cifs_set_acl,
+	.fileattr_get = cifs_fileattr_get,
 };
 
 const char *cifs_get_link(struct dentry *dentry, struct inode *inode,
diff --git a/fs/smb/client/cifsfs.h b/fs/smb/client/cifsfs.h
index c455b15f27782..9d85224fafab5 100644
--- a/fs/smb/client/cifsfs.h
+++ b/fs/smb/client/cifsfs.h
@@ -89,6 +89,9 @@ extern const struct inode_operations cifs_file_inode_ops;
 extern const struct inode_operations cifs_symlink_inode_ops;
 extern const struct inode_operations cifs_namespace_inode_operations;
 
+struct file_kattr;
+int cifs_fileattr_get(struct dentry *dentry, struct file_kattr *fa);
+
 
 /* Functions related to files and directories */
 extern const struct netfs_request_ops cifs_req_ops;
diff --git a/fs/smb/client/namespace.c b/fs/smb/client/namespace.c
index 52a520349cb76..52a51b032fae3 100644
--- a/fs/smb/client/namespace.c
+++ b/fs/smb/client/namespace.c
@@ -294,4 +294,5 @@ struct vfsmount *cifs_d_automount(struct path *path)
 }
 
 const struct inode_operations cifs_namespace_inode_operations = {
+	.fileattr_get	= cifs_fileattr_get,
 };
diff --git a/fs/smb/server/smb2pdu.c b/fs/smb/server/smb2pdu.c
index 62d4399a993d8..406ede2dd9e73 100644
--- a/fs/smb/server/smb2pdu.c
+++ b/fs/smb/server/smb2pdu.c
@@ -14,6 +14,7 @@
 #include <linux/falloc.h>
 #include <linux/mount.h>
 #include <linux/filelock.h>
+#include <linux/fileattr.h>
 
 #include "glob.h"
 #include "smbfsctl.h"
@@ -5550,16 +5551,33 @@ static int smb2_get_info_filesystem(struct ksmbd_work *work,
 	case FS_ATTRIBUTE_INFORMATION:
 	{
 		FILE_SYSTEM_ATTRIBUTE_INFO *info;
+		struct file_kattr fa = {};
 		size_t sz;
+		u32 attrs;
+		int err;
 
 		info = (FILE_SYSTEM_ATTRIBUTE_INFO *)rsp->Buffer;
-		info->Attributes = cpu_to_le32(FILE_SUPPORTS_OBJECT_IDS |
-					       FILE_PERSISTENT_ACLS |
-					       FILE_UNICODE_ON_DISK |
-					       FILE_CASE_PRESERVED_NAMES |
-					       FILE_CASE_SENSITIVE_SEARCH |
-					       FILE_SUPPORTS_BLOCK_REFCOUNTING);
+		attrs = FILE_SUPPORTS_OBJECT_IDS |
+			FILE_PERSISTENT_ACLS |
+			FILE_UNICODE_ON_DISK |
+			FILE_SUPPORTS_BLOCK_REFCOUNTING;
+
+		err = vfs_fileattr_get(path.dentry, &fa);
+		/*
+		 * -EINVAL, -EOPNOTSUPP: ntfs-3g and other FUSE
+		 * filesystems that lack FS_IOC_FSGETXATTR support.
+		 */
+		if (err && err != -ENOIOCTLCMD && err != -ENOTTY &&
+		    err != -EINVAL && err != -EOPNOTSUPP) {
+			path_put(&path);
+			return err;
+		}
+		if (!(fa.fsx_xflags & FS_XFLAG_CASEFOLD))
+			attrs |= FILE_CASE_SENSITIVE_SEARCH;
+		if (!(fa.fsx_xflags & FS_XFLAG_CASENONPRESERVING))
+			attrs |= FILE_CASE_PRESERVED_NAMES;
 
+		info->Attributes = cpu_to_le32(attrs);
 		info->Attributes |= cpu_to_le32(server_conf.share_fake_fscaps);
 
 		if (test_share_config_flag(work->tcon->share_conf,
diff --git a/fs/vboxsf/dir.c b/fs/vboxsf/dir.c
index 42bedc4ec7af7..c5bd3271aa961 100644
--- a/fs/vboxsf/dir.c
+++ b/fs/vboxsf/dir.c
@@ -477,4 +477,5 @@ const struct inode_operations vboxsf_dir_iops = {
 	.symlink = vboxsf_dir_symlink,
 	.getattr = vboxsf_getattr,
 	.setattr = vboxsf_setattr,
+	.fileattr_get = vboxsf_fileattr_get,
 };
diff --git a/fs/vboxsf/file.c b/fs/vboxsf/file.c
index 7a7a3fbb26514..943953867e18e 100644
--- a/fs/vboxsf/file.c
+++ b/fs/vboxsf/file.c
@@ -222,7 +222,8 @@ const struct file_operations vboxsf_reg_fops = {
 
 const struct inode_operations vboxsf_reg_iops = {
 	.getattr = vboxsf_getattr,
-	.setattr = vboxsf_setattr
+	.setattr = vboxsf_setattr,
+	.fileattr_get = vboxsf_fileattr_get,
 };
 
 static int vboxsf_read_folio(struct file *file, struct folio *folio)
@@ -389,5 +390,6 @@ static const char *vboxsf_get_link(struct dentry *dentry, struct inode *inode,
 }
 
 const struct inode_operations vboxsf_lnk_iops = {
-	.get_link = vboxsf_get_link
+	.get_link = vboxsf_get_link,
+	.fileattr_get = vboxsf_fileattr_get,
 };
diff --git a/fs/vboxsf/super.c b/fs/vboxsf/super.c
index a618cb093e007..a61fbab51d370 100644
--- a/fs/vboxsf/super.c
+++ b/fs/vboxsf/super.c
@@ -185,6 +185,13 @@ static int vboxsf_fill_super(struct super_block *sb, struct fs_context *fc)
 	if (err)
 		goto fail_unmap;
 
+	/*
+	 * A failed query leaves sbi->case_insensitive false, so the
+	 * mount defaults to reporting case-sensitive behavior. Do not
+	 * fail the mount over an advisory attribute.
+	 */
+	vboxsf_query_case_sensitive(sbi);
+
 	sb->s_magic = VBOXSF_SUPER_MAGIC;
 	sb->s_blocksize = 1024;
 	sb->s_maxbytes = MAX_LFS_FILESIZE;
diff --git a/fs/vboxsf/utils.c b/fs/vboxsf/utils.c
index 440e8c50629d3..298bfc93255c0 100644
--- a/fs/vboxsf/utils.c
+++ b/fs/vboxsf/utils.c
@@ -11,6 +11,7 @@
 #include <linux/sizes.h>
 #include <linux/pagemap.h>
 #include <linux/vfs.h>
+#include <linux/fileattr.h>
 #include "vfsmod.h"
 
 struct inode *vboxsf_new_inode(struct super_block *sb)
@@ -567,3 +568,32 @@ int vboxsf_dir_read_all(struct vboxsf_sbi *sbi, struct vboxsf_dir_info *sf_d,
 
 	return err;
 }
+
+int vboxsf_query_case_sensitive(struct vboxsf_sbi *sbi)
+{
+	struct shfl_volinfo volinfo = {};
+	u32 buf_len;
+	int err;
+
+	buf_len = sizeof(volinfo);
+	err = vboxsf_fsinfo(sbi->root, 0, SHFL_INFO_GET | SHFL_INFO_VOLUME,
+			    &buf_len, &volinfo);
+	if (err)
+		return err;
+	if (buf_len < sizeof(volinfo))
+		return 0;
+
+	sbi->case_insensitive = !volinfo.properties.case_sensitive;
+	return 0;
+}
+
+int vboxsf_fileattr_get(struct dentry *dentry, struct file_kattr *fa)
+{
+	struct vboxsf_sbi *sbi = VBOXSF_SBI(dentry->d_sb);
+
+	if (sbi->case_insensitive) {
+		fa->fsx_xflags |= FS_XFLAG_CASEFOLD;
+		fa->flags |= FS_CASEFOLD_FL;
+	}
+	return 0;
+}
diff --git a/fs/vboxsf/vfsmod.h b/fs/vboxsf/vfsmod.h
index 05973eb89d528..b61afd0ce842d 100644
--- a/fs/vboxsf/vfsmod.h
+++ b/fs/vboxsf/vfsmod.h
@@ -47,6 +47,7 @@ struct vboxsf_sbi {
 	u32 next_generation;
 	u32 root;
 	int bdi_id;
+	bool case_insensitive;
 };
 
 /* per-inode information */
@@ -111,6 +112,11 @@ void vboxsf_dir_info_free(struct vboxsf_dir_info *p);
 int vboxsf_dir_read_all(struct vboxsf_sbi *sbi, struct vboxsf_dir_info *sf_d,
 			u64 handle);
 
+int vboxsf_query_case_sensitive(struct vboxsf_sbi *sbi);
+
+struct file_kattr;
+int vboxsf_fileattr_get(struct dentry *dentry, struct file_kattr *fa);
+
 /* from vboxsf_wrappers.c */
 int vboxsf_connect(void);
 void vboxsf_disconnect(void);
diff --git a/fs/xfs/libxfs/xfs_inode_util.c b/fs/xfs/libxfs/xfs_inode_util.c
index 551fa51befb65..82be54b6f8d3a 100644
--- a/fs/xfs/libxfs/xfs_inode_util.c
+++ b/fs/xfs/libxfs/xfs_inode_util.c
@@ -130,6 +130,8 @@ xfs_ip2xflags(
 
 	if (xfs_inode_has_attr_fork(ip))
 		flags |= FS_XFLAG_HASATTR;
+	if (xfs_has_asciici(ip->i_mount))
+		flags |= FS_XFLAG_CASEFOLD;
 	return flags;
 }
 
diff --git a/fs/xfs/xfs_ioctl.c b/fs/xfs/xfs_ioctl.c
index 46e234863644f..f8216f74679fd 100644
--- a/fs/xfs/xfs_ioctl.c
+++ b/fs/xfs/xfs_ioctl.c
@@ -517,7 +517,7 @@ 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);
@@ -755,9 +755,23 @@ xfs_fileattr_set(
 	trace_xfs_ioctl_setattr(ip);
 
 	if (!fa->fsx_valid) {
-		if (fa->flags & ~(FS_IMMUTABLE_FL | FS_APPEND_FL |
-				  FS_NOATIME_FL | FS_NODUMP_FL |
-				  FS_SYNC_FL | FS_DAX_FL | FS_PROJINHERIT_FL))
+		unsigned int allowed = FS_IMMUTABLE_FL | FS_APPEND_FL |
+				       FS_NOATIME_FL | FS_NODUMP_FL |
+				       FS_SYNC_FL | FS_DAX_FL |
+				       FS_PROJINHERIT_FL;
+
+		/*
+		 * FS_CASEFOLD_FL reflects the ASCIICI superblock feature,
+		 * a read-only property. Accept it as a no-op so chattr's
+		 * RMW round-trip succeeds; reject any attempt to enable
+		 * it on a non-ASCIICI filesystem. xfs_flags2diflags()
+		 * has no clause for CASEFOLD, so the bit is dropped from
+		 * the on-disk diflags regardless.
+		 */
+		if (xfs_has_asciici(mp))
+			allowed |= FS_CASEFOLD_FL;
+
+		if (fa->flags & ~allowed)
 			return -EOPNOTSUPP;
 	}
author	Christian Brauner <brauner@kernel.org>	2026-05-21 15:34:12 +0200
committer	Christian Brauner <brauner@kernel.org>	2026-05-21 15:34:12 +0200
commit	fda3760fe867b3c5fda044d7fed4ae969a992f7a (patch)
tree	2cf63af290a57f6997c15cfea39df561f89591aa /fs
parent	82ff857a1878bb9502bf66ba73677a47679240f9 (diff)
parent	ea3120fd5153c967efb20e6e3330caecbf9d8b0a (diff)
download	linux-next-history-fda3760fe867b3c5fda044d7fed4ae969a992f7a.tar.gz