fs: port xattr to mnt_idmap

Convert to struct mnt_idmap.

Last cycle we merged the necessary infrastructure in
256c8aed2b42 ("fs: introduce dedicated idmap type for mounts").
This is just the conversion to struct mnt_idmap.

Currently we still pass around the plain namespace that was attached to a
mount. This is in general pretty convenient but it makes it easy to
conflate namespaces that are relevant on the filesystem with namespaces
that are relevent on the mount level. Especially for non-vfs developers
without detailed knowledge in this area this can be a potential source for
bugs.

Once the conversion to struct mnt_idmap is done all helpers down to the
really low-level helpers will take a struct mnt_idmap argument instead of
two namespace arguments. This way it becomes impossible to conflate the two
eliminating the possibility of any bugs. All of the vfs and all filesystems
only operate on struct mnt_idmap.

Acked-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Christian Brauner (Microsoft) <brauner@kernel.org>

41 files changed, 68 insertions, 73 deletions

diff --git a/fs/9p/xattr.c b/fs/9p/xattr.c
index b6984311e00a..50f7f3f6b55e 100644
--- a/fs/9p/xattr.c
+++ b/fs/9p/xattr.c
@@ -150,7 +150,7 @@ static int v9fs_xattr_handler_get(const struct xattr_handler *handler,
 }
 
 static int v9fs_xattr_handler_set(const struct xattr_handler *handler,
-				  struct user_namespace *mnt_userns,
+				  struct mnt_idmap *idmap,
 				  struct dentry *dentry, struct inode *inode,
 				  const char *name, const void *value,
 				  size_t size, int flags)
diff --git a/fs/afs/xattr.c b/fs/afs/xattr.c
index 7751b0b3f81d..9048d8ccc715 100644
--- a/fs/afs/xattr.c
+++ b/fs/afs/xattr.c
@@ -97,7 +97,7 @@ static const struct afs_operation_ops afs_store_acl_operation = {
  * Set a file's AFS3 ACL.
  */
 static int afs_xattr_set_acl(const struct xattr_handler *handler,
-			     struct user_namespace *mnt_userns,
+			     struct mnt_idmap *idmap,
                              struct dentry *dentry,
                              struct inode *inode, const char *name,
                              const void *buffer, size_t size, int flags)
@@ -228,7 +228,7 @@ static const struct afs_operation_ops yfs_store_opaque_acl2_operation = {
  * Set a file's YFS ACL.
  */
 static int afs_xattr_set_yfs(const struct xattr_handler *handler,
-			     struct user_namespace *mnt_userns,
+			     struct mnt_idmap *idmap,
                              struct dentry *dentry,
                              struct inode *inode, const char *name,
                              const void *buffer, size_t size, int flags)
diff --git a/fs/attr.c b/fs/attr.c
index 48897e036ce9..1093db43ab9e 100644
--- a/fs/attr.c
+++ b/fs/attr.c
@@ -220,7 +220,7 @@ kill_priv:
 	if (ia_valid & ATTR_KILL_PRIV) {
 		int error;
 
-		error = security_inode_killpriv(mnt_userns, dentry);
+		error = security_inode_killpriv(idmap, dentry);
 		if (error)
 			return error;
 	}
@@ -489,7 +489,7 @@ int notify_change(struct mnt_idmap *idmap, struct dentry *dentry,
 
 	if (!error) {
 		fsnotify_change(dentry, ia_valid);
-		ima_inode_post_setattr(mnt_userns, dentry);
+		ima_inode_post_setattr(idmap, dentry);
 		evm_inode_post_setattr(dentry, ia_valid);
 	}
 
diff --git a/fs/btrfs/xattr.c b/fs/btrfs/xattr.c
index 0ed4b119a7ca..0ebeaf4e81f9 100644
--- a/fs/btrfs/xattr.c
+++ b/fs/btrfs/xattr.c
@@ -370,7 +370,7 @@ static int btrfs_xattr_handler_get(const struct xattr_handler *handler,
 }
 
 static int btrfs_xattr_handler_set(const struct xattr_handler *handler,
-				   struct user_namespace *mnt_userns,
+				   struct mnt_idmap *idmap,
 				   struct dentry *unused, struct inode *inode,
 				   const char *name, const void *buffer,
 				   size_t size, int flags)
@@ -383,7 +383,7 @@ static int btrfs_xattr_handler_set(const struct xattr_handler *handler,
 }
 
 static int btrfs_xattr_handler_set_prop(const struct xattr_handler *handler,
-					struct user_namespace *mnt_userns,
+					struct mnt_idmap *idmap,
 					struct dentry *unused, struct inode *inode,
 					const char *name, const void *value,
 					size_t size, int flags)
diff --git a/fs/ceph/xattr.c b/fs/ceph/xattr.c
index f31350cda960..f65b07cc33a2 100644
--- a/fs/ceph/xattr.c
+++ b/fs/ceph/xattr.c
@@ -1285,7 +1285,7 @@ static int ceph_get_xattr_handler(const struct xattr_handler *handler,
 }
 
 static int ceph_set_xattr_handler(const struct xattr_handler *handler,
-				  struct user_namespace *mnt_userns,
+				  struct mnt_idmap *idmap,
 				  struct dentry *unused, struct inode *inode,
 				  const char *name, const void *value,
 				  size_t size, int flags)
diff --git a/fs/cifs/xattr.c b/fs/cifs/xattr.c
index 5f2fb2fd2e37..50e762fa1a14 100644
--- a/fs/cifs/xattr.c
+++ b/fs/cifs/xattr.c
@@ -89,7 +89,7 @@ static int cifs_creation_time_set(unsigned int xid, struct cifs_tcon *pTcon,
 }
 
 static int cifs_xattr_set(const struct xattr_handler *handler,
-			  struct user_namespace *mnt_userns,
+			  struct mnt_idmap *idmap,
 			  struct dentry *dentry, struct inode *inode,
 			  const char *name, const void *value,
 			  size_t size, int flags)
diff --git a/fs/ecryptfs/crypto.c b/fs/ecryptfs/crypto.c
index e3f5d7f3c8a0..bd3f3c755b24 100644
--- a/fs/ecryptfs/crypto.c
+++ b/fs/ecryptfs/crypto.c
@@ -1105,7 +1105,7 @@ ecryptfs_write_metadata_to_xattr(struct dentry *ecryptfs_dentry,
 	}
 
 	inode_lock(lower_inode);
-	rc = __vfs_setxattr(&init_user_ns, lower_dentry, lower_inode,
+	rc = __vfs_setxattr(&nop_mnt_idmap, lower_dentry, lower_inode,
 			    ECRYPTFS_XATTR_NAME, page_virt, size, 0);
 	if (!rc && ecryptfs_inode)
 		fsstack_copy_attr_all(ecryptfs_inode, lower_inode);
diff --git a/fs/ecryptfs/inode.c b/fs/ecryptfs/inode.c
index 57bc453415cd..144ace9e0dd9 100644
--- a/fs/ecryptfs/inode.c
+++ b/fs/ecryptfs/inode.c
@@ -1099,7 +1099,7 @@ static int ecryptfs_removexattr(struct dentry *dentry, struct inode *inode,
 		goto out;
 	}
 	inode_lock(lower_inode);
-	rc = __vfs_removexattr(&init_user_ns, lower_dentry, name);
+	rc = __vfs_removexattr(&nop_mnt_idmap, lower_dentry, name);
 	inode_unlock(lower_inode);
 out:
 	return rc;
@@ -1190,7 +1190,7 @@ static int ecryptfs_xattr_get(const struct xattr_handler *handler,
 }
 
 static int ecryptfs_xattr_set(const struct xattr_handler *handler,
-			      struct user_namespace *mnt_userns,
+			      struct mnt_idmap *idmap,
 			      struct dentry *dentry, struct inode *inode,
 			      const char *name, const void *value, size_t size,
 			      int flags)
diff --git a/fs/ecryptfs/mmap.c b/fs/ecryptfs/mmap.c
index 19af229eb7ca..373c3e5747e6 100644
--- a/fs/ecryptfs/mmap.c
+++ b/fs/ecryptfs/mmap.c
@@ -428,7 +428,7 @@ static int ecryptfs_write_inode_size_to_xattr(struct inode *ecryptfs_inode)
 	if (size < 0)
 		size = 8;
 	put_unaligned_be64(i_size_read(ecryptfs_inode), xattr_virt);
-	rc = __vfs_setxattr(&init_user_ns, lower_dentry, lower_inode,
+	rc = __vfs_setxattr(&nop_mnt_idmap, lower_dentry, lower_inode,
 			    ECRYPTFS_XATTR_NAME, xattr_virt, size, 0);
 	inode_unlock(lower_inode);
 	if (rc)
diff --git a/fs/ext2/xattr_security.c b/fs/ext2/xattr_security.c
index ebade1f52451..db47b8ab153e 100644
--- a/fs/ext2/xattr_security.c
+++ b/fs/ext2/xattr_security.c
@@ -19,7 +19,7 @@ ext2_xattr_security_get(const struct xattr_handler *handler,
 
 static int
 ext2_xattr_security_set(const struct xattr_handler *handler,
-			struct user_namespace *mnt_userns,
+			struct mnt_idmap *idmap,
 			struct dentry *unused, struct inode *inode,
 			const char *name, const void *value,
 			size_t size, int flags)
diff --git a/fs/ext2/xattr_trusted.c b/fs/ext2/xattr_trusted.c
index 18a87d5dd1ab..995f931228ce 100644
--- a/fs/ext2/xattr_trusted.c
+++ b/fs/ext2/xattr_trusted.c
@@ -26,7 +26,7 @@ ext2_xattr_trusted_get(const struct xattr_handler *handler,
 
 static int
 ext2_xattr_trusted_set(const struct xattr_handler *handler,
-		       struct user_namespace *mnt_userns,
+		       struct mnt_idmap *idmap,
 		       struct dentry *unused, struct inode *inode,
 		       const char *name, const void *value,
 		       size_t size, int flags)
diff --git a/fs/ext2/xattr_user.c b/fs/ext2/xattr_user.c
index 58092449f8ff..dd1507231081 100644
--- a/fs/ext2/xattr_user.c
+++ b/fs/ext2/xattr_user.c
@@ -30,7 +30,7 @@ ext2_xattr_user_get(const struct xattr_handler *handler,
 
 static int
 ext2_xattr_user_set(const struct xattr_handler *handler,
-		    struct user_namespace *mnt_userns,
+		    struct mnt_idmap *idmap,
 		    struct dentry *unused, struct inode *inode,
 		    const char *name, const void *value,
 		    size_t size, int flags)
diff --git a/fs/ext4/xattr_hurd.c b/fs/ext4/xattr_hurd.c
index c78df5790377..8a5842e4cd95 100644
--- a/fs/ext4/xattr_hurd.c
+++ b/fs/ext4/xattr_hurd.c
@@ -32,7 +32,7 @@ ext4_xattr_hurd_get(const struct xattr_handler *handler,
 
 static int
 ext4_xattr_hurd_set(const struct xattr_handler *handler,
-		    struct user_namespace *mnt_userns,
+		    struct mnt_idmap *idmap,
 		    struct dentry *unused, struct inode *inode,
 		    const char *name, const void *value,
 		    size_t size, int flags)
diff --git a/fs/ext4/xattr_security.c b/fs/ext4/xattr_security.c
index 8213f66f7b2d..776cf11d24ca 100644
--- a/fs/ext4/xattr_security.c
+++ b/fs/ext4/xattr_security.c
@@ -23,7 +23,7 @@ ext4_xattr_security_get(const struct xattr_handler *handler,
 
 static int
 ext4_xattr_security_set(const struct xattr_handler *handler,
-			struct user_namespace *mnt_userns,
+			struct mnt_idmap *idmap,
 			struct dentry *unused, struct inode *inode,
 			const char *name, const void *value,
 			size_t size, int flags)
diff --git a/fs/ext4/xattr_trusted.c b/fs/ext4/xattr_trusted.c
index 7c21ffb26d25..9811eb0ab276 100644
--- a/fs/ext4/xattr_trusted.c
+++ b/fs/ext4/xattr_trusted.c
@@ -30,7 +30,7 @@ ext4_xattr_trusted_get(const struct xattr_handler *handler,
 
 static int
 ext4_xattr_trusted_set(const struct xattr_handler *handler,
-		       struct user_namespace *mnt_userns,
+		       struct mnt_idmap *idmap,
 		       struct dentry *unused, struct inode *inode,
 		       const char *name, const void *value,
 		       size_t size, int flags)
diff --git a/fs/ext4/xattr_user.c b/fs/ext4/xattr_user.c
index 2fe7ff0a479c..4b70bf4e7626 100644
--- a/fs/ext4/xattr_user.c
+++ b/fs/ext4/xattr_user.c
@@ -31,7 +31,7 @@ ext4_xattr_user_get(const struct xattr_handler *handler,
 
 static int
 ext4_xattr_user_set(const struct xattr_handler *handler,
-		    struct user_namespace *mnt_userns,
+		    struct mnt_idmap *idmap,
 		    struct dentry *unused, struct inode *inode,
 		    const char *name, const void *value,
 		    size_t size, int flags)
diff --git a/fs/f2fs/xattr.c b/fs/f2fs/xattr.c
index dc2e8637189e..044b74322ec4 100644
--- a/fs/f2fs/xattr.c
+++ b/fs/f2fs/xattr.c
@@ -65,7 +65,7 @@ static int f2fs_xattr_generic_get(const struct xattr_handler *handler,
 }
 
 static int f2fs_xattr_generic_set(const struct xattr_handler *handler,
-		struct user_namespace *mnt_userns,
+		struct mnt_idmap *idmap,
 		struct dentry *unused, struct inode *inode,
 		const char *name, const void *value,
 		size_t size, int flags)
@@ -109,7 +109,7 @@ static int f2fs_xattr_advise_get(const struct xattr_handler *handler,
 }
 
 static int f2fs_xattr_advise_set(const struct xattr_handler *handler,
-		struct user_namespace *mnt_userns,
+		struct mnt_idmap *idmap,
 		struct dentry *unused, struct inode *inode,
 		const char *name, const void *value,
 		size_t size, int flags)
diff --git a/fs/fuse/xattr.c b/fs/fuse/xattr.c
index 0d3e7177fce0..30aaaa4b3bfb 100644
--- a/fs/fuse/xattr.c
+++ b/fs/fuse/xattr.c
@@ -189,7 +189,7 @@ static int fuse_xattr_get(const struct xattr_handler *handler,
 }
 
 static int fuse_xattr_set(const struct xattr_handler *handler,
-			  struct user_namespace *mnt_userns,
+			  struct mnt_idmap *idmap,
 			  struct dentry *dentry, struct inode *inode,
 			  const char *name, const void *value, size_t size,
 			  int flags)
@@ -216,7 +216,7 @@ static int no_xattr_get(const struct xattr_handler *handler,
 }
 
 static int no_xattr_set(const struct xattr_handler *handler,
-			struct user_namespace *mnt_userns,
+			struct mnt_idmap *idmap,
 			struct dentry *dentry, struct inode *nodee,
 			const char *name, const void *value,
 			size_t size, int flags)
diff --git a/fs/gfs2/xattr.c b/fs/gfs2/xattr.c
index 518c0677e12a..adf6d17cf033 100644
--- a/fs/gfs2/xattr.c
+++ b/fs/gfs2/xattr.c
@@ -1225,7 +1225,7 @@ int __gfs2_xattr_set(struct inode *inode, const char *name,
 }
 
 static int gfs2_xattr_set(const struct xattr_handler *handler,
-			  struct user_namespace *mnt_userns,
+			  struct mnt_idmap *idmap,
 			  struct dentry *unused, struct inode *inode,
 			  const char *name, const void *value,
 			  size_t size, int flags)
diff --git a/fs/hfs/attr.c b/fs/hfs/attr.c
index 2bd54efaf416..6341bb248247 100644
--- a/fs/hfs/attr.c
+++ b/fs/hfs/attr.c
@@ -121,7 +121,7 @@ static int hfs_xattr_get(const struct xattr_handler *handler,
 }
 
 static int hfs_xattr_set(const struct xattr_handler *handler,
-			 struct user_namespace *mnt_userns,
+			 struct mnt_idmap *idmap,
 			 struct dentry *unused, struct inode *inode,
 			 const char *name, const void *value, size_t size,
 			 int flags)
diff --git a/fs/hfsplus/xattr.c b/fs/hfsplus/xattr.c
index 49891b12c415..5b476f57eb17 100644
--- a/fs/hfsplus/xattr.c
+++ b/fs/hfsplus/xattr.c
@@ -857,7 +857,7 @@ static int hfsplus_osx_getxattr(const struct xattr_handler *handler,
 }
 
 static int hfsplus_osx_setxattr(const struct xattr_handler *handler,
-				struct user_namespace *mnt_userns,
+				struct mnt_idmap *idmap,
 				struct dentry *unused, struct inode *inode,
 				const char *name, const void *buffer,
 				size_t size, int flags)
diff --git a/fs/hfsplus/xattr_security.c b/fs/hfsplus/xattr_security.c
index c1c7a16cbf21..90f68ec119cd 100644
--- a/fs/hfsplus/xattr_security.c
+++ b/fs/hfsplus/xattr_security.c
@@ -23,7 +23,7 @@ static int hfsplus_security_getxattr(const struct xattr_handler *handler,
 }
 
 static int hfsplus_security_setxattr(const struct xattr_handler *handler,
-				     struct user_namespace *mnt_userns,
+				     struct mnt_idmap *idmap,
 				     struct dentry *unused, struct inode *inode,
 				     const char *name, const void *buffer,
 				     size_t size, int flags)
diff --git a/fs/hfsplus/xattr_trusted.c b/fs/hfsplus/xattr_trusted.c
index e150372ec564..fdbaebc1c49a 100644
--- a/fs/hfsplus/xattr_trusted.c
+++ b/fs/hfsplus/xattr_trusted.c
@@ -22,7 +22,7 @@ static int hfsplus_trusted_getxattr(const struct xattr_handler *handler,
 }
 
 static int hfsplus_trusted_setxattr(const struct xattr_handler *handler,
-				    struct user_namespace *mnt_userns,
+				    struct mnt_idmap *idmap,
 				    struct dentry *unused, struct inode *inode,
 				    const char *name, const void *buffer,
 				    size_t size, int flags)
diff --git a/fs/hfsplus/xattr_user.c b/fs/hfsplus/xattr_user.c
index a6b60b153916..6464b6c3d58d 100644
--- a/fs/hfsplus/xattr_user.c
+++ b/fs/hfsplus/xattr_user.c
@@ -22,7 +22,7 @@ static int hfsplus_user_getxattr(const struct xattr_handler *handler,
 }
 
 static int hfsplus_user_setxattr(const struct xattr_handler *handler,
-				 struct user_namespace *mnt_userns,
+				 struct mnt_idmap *idmap,
 				 struct dentry *unused, struct inode *inode,
 				 const char *name, const void *buffer,
 				 size_t size, int flags)
diff --git a/fs/jffs2/security.c b/fs/jffs2/security.c
index aef5522551db..437f3a2c1b54 100644
--- a/fs/jffs2/security.c
+++ b/fs/jffs2/security.c
@@ -57,7 +57,7 @@ static int jffs2_security_getxattr(const struct xattr_handler *handler,
 }
 
 static int jffs2_security_setxattr(const struct xattr_handler *handler,
-				   struct user_namespace *mnt_userns,
+				   struct mnt_idmap *idmap,
 				   struct dentry *unused, struct inode *inode,
 				   const char *name, const void *buffer,
 				   size_t size, int flags)
diff --git a/fs/jffs2/xattr_trusted.c b/fs/jffs2/xattr_trusted.c
index cc3f24883e7d..b7c5da2d89bd 100644
--- a/fs/jffs2/xattr_trusted.c
+++ b/fs/jffs2/xattr_trusted.c
@@ -25,7 +25,7 @@ static int jffs2_trusted_getxattr(const struct xattr_handler *handler,
 }
 
 static int jffs2_trusted_setxattr(const struct xattr_handler *handler,
-				  struct user_namespace *mnt_userns,
+				  struct mnt_idmap *idmap,
 				  struct dentry *unused, struct inode *inode,
 				  const char *name, const void *buffer,
 				  size_t size, int flags)
diff --git a/fs/jffs2/xattr_user.c b/fs/jffs2/xattr_user.c
index fb945977c013..f64edce4927b 100644
--- a/fs/jffs2/xattr_user.c
+++ b/fs/jffs2/xattr_user.c
@@ -25,7 +25,7 @@ static int jffs2_user_getxattr(const struct xattr_handler *handler,
 }
 
 static int jffs2_user_setxattr(const struct xattr_handler *handler,
-			       struct user_namespace *mnt_userns,
+			       struct mnt_idmap *idmap,
 			       struct dentry *unused, struct inode *inode,
 			       const char *name, const void *buffer,
 			       size_t size, int flags)
diff --git a/fs/jfs/xattr.c b/fs/jfs/xattr.c
index f9273f6901c8..f817798fa1eb 100644
--- a/fs/jfs/xattr.c
+++ b/fs/jfs/xattr.c
@@ -932,7 +932,7 @@ static int jfs_xattr_get(const struct xattr_handler *handler,
 }
 
 static int jfs_xattr_set(const struct xattr_handler *handler,
-			 struct user_namespace *mnt_userns,
+			 struct mnt_idmap *idmap,
 			 struct dentry *unused, struct inode *inode,
 			 const char *name, const void *value,
 			 size_t size, int flags)
@@ -951,7 +951,7 @@ static int jfs_xattr_get_os2(const struct xattr_handler *handler,
 }
 
 static int jfs_xattr_set_os2(const struct xattr_handler *handler,
-			     struct user_namespace *mnt_userns,
+			     struct mnt_idmap *idmap,
 			     struct dentry *unused, struct inode *inode,
 			     const char *name, const void *value,
 			     size_t size, int flags)
diff --git a/fs/kernfs/inode.c b/fs/kernfs/inode.c
index af1a05470131..30494dcb0df3 100644
--- a/fs/kernfs/inode.c
+++ b/fs/kernfs/inode.c
@@ -324,7 +324,7 @@ static int kernfs_vfs_xattr_get(const struct xattr_handler *handler,
 }
 
 static int kernfs_vfs_xattr_set(const struct xattr_handler *handler,
-				struct user_namespace *mnt_userns,
+				struct mnt_idmap *idmap,
 				struct dentry *unused, struct inode *inode,
 				const char *suffix, const void *value,
 				size_t size, int flags)
@@ -391,7 +391,7 @@ static int kernfs_vfs_user_xattr_rm(struct kernfs_node *kn,
 }
 
 static int kernfs_vfs_user_xattr_set(const struct xattr_handler *handler,
-				     struct user_namespace *mnt_userns,
+				     struct mnt_idmap *idmap,
 				     struct dentry *unused, struct inode *inode,
 				     const char *suffix, const void *value,
 				     size_t size, int flags)
diff --git a/fs/namei.c b/fs/namei.c
index e483738b2661..a88017266ee5 100644
--- a/fs/namei.c
+++ b/fs/namei.c
@@ -3633,7 +3633,7 @@ static int vfs_tmpfile(struct mnt_idmap *idmap,
 		inode->i_state |= I_LINKABLE;
 		spin_unlock(&inode->i_lock);
 	}
-	ima_post_create_tmpfile(mnt_userns, inode);
+	ima_post_create_tmpfile(idmap, inode);
 	return 0;
 }
 
@@ -3953,7 +3953,6 @@ static int do_mknodat(int dfd, struct filename *name, umode_t mode,
 		unsigned int dev)
 {
 	struct mnt_idmap *idmap;
-	struct user_namespace *mnt_userns;
 	struct dentry *dentry;
 	struct path path;
 	int error;
@@ -3974,13 +3973,12 @@ retry:
 		goto out2;
 
 	idmap = mnt_idmap(path.mnt);
-	mnt_userns = mnt_idmap_owner(idmap);
 	switch (mode & S_IFMT) {
 		case 0: case S_IFREG:
 			error = vfs_create(idmap, path.dentry->d_inode,
 					   dentry, mode, true);
 			if (!error)
-				ima_post_path_mknod(mnt_userns, dentry);
+				ima_post_path_mknod(idmap, dentry);
 			break;
 		case S_IFCHR: case S_IFBLK:
 			error = vfs_mknod(idmap, path.dentry->d_inode,
diff --git a/fs/nfs/nfs4proc.c b/fs/nfs/nfs4proc.c
index 40d749f29ed3..d9c332019d06 100644
--- a/fs/nfs/nfs4proc.c
+++ b/fs/nfs/nfs4proc.c
@@ -7692,7 +7692,7 @@ nfs4_release_lockowner(struct nfs_server *server, struct nfs4_lock_state *lsp)
 #define XATTR_NAME_NFSV4_ACL "system.nfs4_acl"
 
 static int nfs4_xattr_set_nfs4_acl(const struct xattr_handler *handler,
-				   struct user_namespace *mnt_userns,
+				   struct mnt_idmap *idmap,
 				   struct dentry *unused, struct inode *inode,
 				   const char *key, const void *buf,
 				   size_t buflen, int flags)
@@ -7716,7 +7716,7 @@ static bool nfs4_xattr_list_nfs4_acl(struct dentry *dentry)
 #define XATTR_NAME_NFSV4_DACL "system.nfs4_dacl"
 
 static int nfs4_xattr_set_nfs4_dacl(const struct xattr_handler *handler,
-				    struct user_namespace *mnt_userns,
+				    struct mnt_idmap *idmap,
 				    struct dentry *unused, struct inode *inode,
 				    const char *key, const void *buf,
 				    size_t buflen, int flags)
@@ -7739,7 +7739,7 @@ static bool nfs4_xattr_list_nfs4_dacl(struct dentry *dentry)
 #define XATTR_NAME_NFSV4_SACL "system.nfs4_sacl"
 
 static int nfs4_xattr_set_nfs4_sacl(const struct xattr_handler *handler,
-				    struct user_namespace *mnt_userns,
+				    struct mnt_idmap *idmap,
 				    struct dentry *unused, struct inode *inode,
 				    const char *key, const void *buf,
 				    size_t buflen, int flags)
@@ -7764,7 +7764,7 @@ static bool nfs4_xattr_list_nfs4_sacl(struct dentry *dentry)
 #ifdef CONFIG_NFS_V4_SECURITY_LABEL
 
 static int nfs4_xattr_set_nfs4_label(const struct xattr_handler *handler,
-				     struct user_namespace *mnt_userns,
+				     struct mnt_idmap *idmap,
 				     struct dentry *unused, struct inode *inode,
 				     const char *key, const void *buf,
 				     size_t buflen, int flags)
@@ -7815,7 +7815,7 @@ nfs4_listxattr_nfs4_label(struct inode *inode, char *list, size_t list_len)
 
 #ifdef CONFIG_NFS_V4_2
 static int nfs4_xattr_set_nfs4_user(const struct xattr_handler *handler,
-				    struct user_namespace *mnt_userns,
+				    struct mnt_idmap *idmap,
 				    struct dentry *unused, struct inode *inode,
 				    const char *key, const void *buf,
 				    size_t buflen, int flags)
diff --git a/fs/ntfs3/xattr.c b/fs/ntfs3/xattr.c
index 42b8eec72ba0..55ee27c96a4d 100644
--- a/fs/ntfs3/xattr.c
+++ b/fs/ntfs3/xattr.c
@@ -837,7 +837,7 @@ out:
  * ntfs_setxattr - inode_operations::setxattr
  */
 static noinline int ntfs_setxattr(const struct xattr_handler *handler,
-				  struct user_namespace *mnt_userns,
+				  struct mnt_idmap *idmap,
 				  struct dentry *de, struct inode *inode,
 				  const char *name, const void *value,
 				  size_t size, int flags)
diff --git a/fs/ocfs2/xattr.c b/fs/ocfs2/xattr.c
index 95d0611c5fc7..389308efe854 100644
--- a/fs/ocfs2/xattr.c
+++ b/fs/ocfs2/xattr.c
@@ -7247,7 +7247,7 @@ static int ocfs2_xattr_security_get(const struct xattr_handler *handler,
 }
 
 static int ocfs2_xattr_security_set(const struct xattr_handler *handler,
-				    struct user_namespace *mnt_userns,
+				    struct mnt_idmap *idmap,
 				    struct dentry *unused, struct inode *inode,
 				    const char *name, const void *value,
 				    size_t size, int flags)
@@ -7320,7 +7320,7 @@ static int ocfs2_xattr_trusted_get(const struct xattr_handler *handler,
 }
 
 static int ocfs2_xattr_trusted_set(const struct xattr_handler *handler,
-				   struct user_namespace *mnt_userns,
+				   struct mnt_idmap *idmap,
 				   struct dentry *unused, struct inode *inode,
 				   const char *name, const void *value,
 				   size_t size, int flags)
@@ -7351,7 +7351,7 @@ static int ocfs2_xattr_user_get(const struct xattr_handler *handler,
 }
 
 static int ocfs2_xattr_user_set(const struct xattr_handler *handler,
-				struct user_namespace *mnt_userns,
+				struct mnt_idmap *idmap,
 				struct dentry *unused, struct inode *inode,
 				const char *name, const void *value,
 				size_t size, int flags)
diff --git a/fs/orangefs/xattr.c b/fs/orangefs/xattr.c
index 9a5b757fbd2f..6ecad4f94ae6 100644
--- a/fs/orangefs/xattr.c
+++ b/fs/orangefs/xattr.c
@@ -526,7 +526,7 @@ out_unlock:
 }
 
 static int orangefs_xattr_set_default(const struct xattr_handler *handler,
-				      struct user_namespace *mnt_userns,
+				      struct mnt_idmap *idmap,
 				      struct dentry *unused,
 				      struct inode *inode,
 				      const char *name,
diff --git a/fs/overlayfs/super.c b/fs/overlayfs/super.c
index 85b891152a2c..f1d9f75f8786 100644
--- a/fs/overlayfs/super.c
+++ b/fs/overlayfs/super.c
@@ -1012,7 +1012,7 @@ static int ovl_own_xattr_get(const struct xattr_handler *handler,
 }
 
 static int ovl_own_xattr_set(const struct xattr_handler *handler,
-			     struct user_namespace *mnt_userns,
+			     struct mnt_idmap *idmap,
 			     struct dentry *dentry, struct inode *inode,
 			     const char *name, const void *value,
 			     size_t size, int flags)
@@ -1028,7 +1028,7 @@ static int ovl_other_xattr_get(const struct xattr_handler *handler,
 }
 
 static int ovl_other_xattr_set(const struct xattr_handler *handler,
-			       struct user_namespace *mnt_userns,
+			       struct mnt_idmap *idmap,
 			       struct dentry *dentry, struct inode *inode,
 			       const char *name, const void *value,
 			       size_t size, int flags)
diff --git a/fs/reiserfs/xattr_security.c b/fs/reiserfs/xattr_security.c
index 857a65b05726..41c0ea84fbff 100644
--- a/fs/reiserfs/xattr_security.c
+++ b/fs/reiserfs/xattr_security.c
@@ -22,7 +22,7 @@ security_get(const struct xattr_handler *handler, struct dentry *unused,
 
 static int
 security_set(const struct xattr_handler *handler,
-	     struct user_namespace *mnt_userns, struct dentry *unused,
+	     struct mnt_idmap *idmap, struct dentry *unused,
 	     struct inode *inode, const char *name, const void *buffer,
 	     size_t size, int flags)
 {
diff --git a/fs/reiserfs/xattr_trusted.c b/fs/reiserfs/xattr_trusted.c
index d853cea2afcd..0c0c74d8db0e 100644
--- a/fs/reiserfs/xattr_trusted.c
+++ b/fs/reiserfs/xattr_trusted.c
@@ -21,7 +21,7 @@ trusted_get(const struct xattr_handler *handler, struct dentry *unused,
 
 static int
 trusted_set(const struct xattr_handler *handler,
-	    struct user_namespace *mnt_userns, struct dentry *unused,
+	    struct mnt_idmap *idmap, struct dentry *unused,
 	    struct inode *inode, const char *name, const void *buffer,
 	    size_t size, int flags)
 {
diff --git a/fs/reiserfs/xattr_user.c b/fs/reiserfs/xattr_user.c
index 65d9cd10a5ea..88195181e1d7 100644
--- a/fs/reiserfs/xattr_user.c
+++ b/fs/reiserfs/xattr_user.c
@@ -18,7 +18,7 @@ user_get(const struct xattr_handler *handler, struct dentry *unused,
 }
 
 static int
-user_set(const struct xattr_handler *handler, struct user_namespace *mnt_userns,
+user_set(const struct xattr_handler *handler, struct mnt_idmap *idmap,
 	 struct dentry *unused,
 	 struct inode *inode, const char *name, const void *buffer,
 	 size_t size, int flags)
diff --git a/fs/ubifs/xattr.c b/fs/ubifs/xattr.c
index 3db8486e3725..349228dd1191 100644
--- a/fs/ubifs/xattr.c
+++ b/fs/ubifs/xattr.c
@@ -699,7 +699,7 @@ static int xattr_get(const struct xattr_handler *handler,
 }
 
 static int xattr_set(const struct xattr_handler *handler,
-			   struct user_namespace *mnt_userns,
+			   struct mnt_idmap *idmap,
 			   struct dentry *dentry, struct inode *inode,
 			   const char *name, const void *value,
 			   size_t size, int flags)
diff --git a/fs/xattr.c b/fs/xattr.c
index d056d9ac247a..1cc1420eccce 100644
--- a/fs/xattr.c
+++ b/fs/xattr.c
@@ -185,7 +185,7 @@ xattr_supported_namespace(struct inode *inode, const char *prefix)
 EXPORT_SYMBOL(xattr_supported_namespace);
 
 int
-__vfs_setxattr(struct user_namespace *mnt_userns, struct dentry *dentry,
+__vfs_setxattr(struct mnt_idmap *idmap, struct dentry *dentry,
 	       struct inode *inode, const char *name, const void *value,
 	       size_t size, int flags)
 {
@@ -201,7 +201,7 @@ __vfs_setxattr(struct user_namespace *mnt_userns, struct dentry *dentry,
 		return -EOPNOTSUPP;
 	if (size == 0)
 		value = "";  /* empty EA, do not remove */
-	return handler->set(handler, mnt_userns, dentry, inode, name, value,
+	return handler->set(handler, idmap, dentry, inode, name, value,
 			    size, flags);
 }
 EXPORT_SYMBOL(__vfs_setxattr);
@@ -210,7 +210,7 @@ EXPORT_SYMBOL(__vfs_setxattr);
  *  __vfs_setxattr_noperm - perform setxattr operation without performing
  *  permission checks.
  *
- *  @mnt_userns: user namespace of the mount the inode was found from
+ *  @idmap: idmap of the mount the inode was found from
  *  @dentry: object to perform setxattr on
  *  @name: xattr name to set
  *  @value: value to set @name to
@@ -223,7 +223,7 @@ EXPORT_SYMBOL(__vfs_setxattr);
  *  is executed. It also assumes that the caller will make the appropriate
  *  permission checks.
  */
-int __vfs_setxattr_noperm(struct user_namespace *mnt_userns,
+int __vfs_setxattr_noperm(struct mnt_idmap *idmap,
 			  struct dentry *dentry, const char *name,
 			  const void *value, size_t size, int flags)
 {
@@ -235,7 +235,7 @@ int __vfs_setxattr_noperm(struct user_namespace *mnt_userns,
 	if (issec)
 		inode->i_flags &= ~S_NOSEC;
 	if (inode->i_opflags & IOP_XATTR) {
-		error = __vfs_setxattr(mnt_userns, dentry, inode, name, value,
+		error = __vfs_setxattr(idmap, dentry, inode, name, value,
 				       size, flags);
 		if (!error) {
 			fsnotify_xattr(dentry);
@@ -280,7 +280,6 @@ __vfs_setxattr_locked(struct mnt_idmap *idmap, struct dentry *dentry,
 		      const char *name, const void *value, size_t size,
 		      int flags, struct inode **delegated_inode)
 {
-	struct user_namespace *mnt_userns = mnt_idmap_owner(idmap);
 	struct inode *inode = dentry->d_inode;
 	int error;
 
@@ -288,7 +287,7 @@ __vfs_setxattr_locked(struct mnt_idmap *idmap, struct dentry *dentry,
 	if (error)
 		return error;
 
-	error = security_inode_setxattr(mnt_userns, dentry, name, value, size,
+	error = security_inode_setxattr(idmap, dentry, name, value, size,
 					flags);
 	if (error)
 		goto out;
@@ -297,7 +296,7 @@ __vfs_setxattr_locked(struct mnt_idmap *idmap, struct dentry *dentry,
 	if (error)
 		goto out;
 
-	error = __vfs_setxattr_noperm(mnt_userns, dentry, name, value,
+	error = __vfs_setxattr_noperm(idmap, dentry, name, value,
 				      size, flags);
 
 out:
@@ -309,14 +308,13 @@ int
 vfs_setxattr(struct mnt_idmap *idmap, struct dentry *dentry,
 	     const char *name, const void *value, size_t size, int flags)
 {
-	struct user_namespace *mnt_userns = mnt_idmap_owner(idmap);
 	struct inode *inode = dentry->d_inode;
 	struct inode *delegated_inode = NULL;
 	const void  *orig_value = value;
 	int error;
 
 	if (size && strcmp(name, XATTR_NAME_CAPS) == 0) {
-		error = cap_convert_nscap(mnt_userns, dentry, &value, size);
+		error = cap_convert_nscap(idmap, dentry, &value, size);
 		if (error < 0)
 			return error;
 		size = error;
@@ -484,7 +482,7 @@ vfs_listxattr(struct dentry *dentry, char *list, size_t size)
 EXPORT_SYMBOL_GPL(vfs_listxattr);
 
 int
-__vfs_removexattr(struct user_namespace *mnt_userns, struct dentry *dentry,
+__vfs_removexattr(struct mnt_idmap *idmap, struct dentry *dentry,
 		  const char *name)
 {
 	struct inode *inode = d_inode(dentry);
@@ -498,7 +496,7 @@ __vfs_removexattr(struct user_namespace *mnt_userns, struct dentry *dentry,
 		return PTR_ERR(handler);
 	if (!handler->set)
 		return -EOPNOTSUPP;
-	return handler->set(handler, mnt_userns, dentry, inode, name, NULL, 0,
+	return handler->set(handler, idmap, dentry, inode, name, NULL, 0,
 			    XATTR_REPLACE);
 }
 EXPORT_SYMBOL(__vfs_removexattr);
@@ -518,7 +516,6 @@ __vfs_removexattr_locked(struct mnt_idmap *idmap,
 			 struct dentry *dentry, const char *name,
 			 struct inode **delegated_inode)
 {
-	struct user_namespace *mnt_userns = mnt_idmap_owner(idmap);
 	struct inode *inode = dentry->d_inode;
 	int error;
 
@@ -526,7 +523,7 @@ __vfs_removexattr_locked(struct mnt_idmap *idmap,
 	if (error)
 		return error;
 
-	error = security_inode_removexattr(mnt_userns, dentry, name);
+	error = security_inode_removexattr(idmap, dentry, name);
 	if (error)
 		goto out;
 
@@ -534,7 +531,7 @@ __vfs_removexattr_locked(struct mnt_idmap *idmap,
 	if (error)
 		goto out;
 
-	error = __vfs_removexattr(mnt_userns, dentry, name);
+	error = __vfs_removexattr(idmap, dentry, name);
 
 	if (!error) {
 		fsnotify_xattr(dentry);
diff --git a/fs/xfs/xfs_xattr.c b/fs/xfs/xfs_xattr.c
index 10aa1fd39d2b..7b9a0ed1b11f 100644
--- a/fs/xfs/xfs_xattr.c
+++ b/fs/xfs/xfs_xattr.c
@@ -133,7 +133,7 @@ xfs_xattr_get(const struct xattr_handler *handler, struct dentry *unused,
 
 static int
 xfs_xattr_set(const struct xattr_handler *handler,
-	      struct user_namespace *mnt_userns, struct dentry *unused,
+	      struct mnt_idmap *idmap, struct dentry *unused,
 	      struct inode *inode, const char *name, const void *value,
 	      size_t size, int flags)
 {