--- zzzz-none-000/linux-5.4.213/fs/exportfs/expfs.c	2022-09-15 10:04:56.000000000 +0000
+++ miami-7690-761/linux-5.4.213/fs/exportfs/expfs.c	2024-05-29 11:20:02.000000000 +0000
@@ -344,20 +344,21 @@
 }
 
 /**
- * export_encode_fh - default export_operations->encode_fh function
+ * generic_encode_ino32_fh - generic export_operations->encode_fh function
  * @inode:   the object to encode
- * @fid:     where to store the file handle fragment
- * @max_len: maximum length to store there
+ * @fh:      where to store the file handle fragment
+ * @max_len: maximum length to store there (in 4 byte units)
  * @parent:  parent directory inode, if wanted
  *
- * This default encode_fh function assumes that the 32 inode number
+ * This generic encode_fh function assumes that the 32 inode number
  * is suitable for locating an inode, and that the generation number
  * can be used to check that it is still valid.  It places them in the
  * filehandle fragment where export_decode_fh expects to find them.
  */
-static int export_encode_fh(struct inode *inode, struct fid *fid,
-		int *max_len, struct inode *parent)
+int generic_encode_ino32_fh(struct inode *inode, __u32 *fh, int *max_len,
+			    struct inode *parent)
 {
+	struct fid *fid = (void *)fh;
 	int len = *max_len;
 	int type = FILEID_INO32_GEN;
 
@@ -381,27 +382,75 @@
 	*max_len = len;
 	return type;
 }
+EXPORT_SYMBOL_GPL(generic_encode_ino32_fh);
+
+#define FILEID_INO64_GEN_LEN 3
+
+/**
+ * exportfs_encode_ino64_fid - encode non-decodeable 64bit ino file id
+ * @inode:   the object to encode
+ * @fid:     where to store the file handle fragment
+ * @max_len: maximum length to store there (in 4 byte units)
+ *
+ * This generic function is used to encode a non-decodeable file id for
+ * fanotify for filesystems that do not support NFS export.
+ */
+static int exportfs_encode_ino64_fid(struct inode *inode, struct fid *fid,
+				     int *max_len)
+{
+	if (*max_len < FILEID_INO64_GEN_LEN) {
+		*max_len = FILEID_INO64_GEN_LEN;
+		return FILEID_INVALID;
+	}
+
+	fid->i64.ino = inode->i_ino;
+	fid->i64.gen = inode->i_generation;
+	*max_len = FILEID_INO64_GEN_LEN;
 
+	return FILEID_INO64_GEN;
+}
+
+/**
+ * exportfs_encode_inode_fh - encode a file handle from inode
+ * @inode:   the object to encode
+ * @fid:     where to store the file handle fragment
+ * @max_len: maximum length to store there
+ * @flags:   properties of the requested file handle
+ *
+ * Returns an enum fid_type or a negative errno.
+ */
 int exportfs_encode_inode_fh(struct inode *inode, struct fid *fid,
-			     int *max_len, struct inode *parent)
+			     int *max_len, struct inode *parent, int flags)
 {
 	const struct export_operations *nop = inode->i_sb->s_export_op;
 
-	if (nop && nop->encode_fh)
-		return nop->encode_fh(inode, fid->raw, max_len, parent);
+	if (!exportfs_can_encode_fh(nop, flags))
+		return -EOPNOTSUPP;
 
-	return export_encode_fh(inode, fid, max_len, parent);
+	if (!nop && (flags & EXPORT_FH_FID))
+		return exportfs_encode_ino64_fid(inode, fid, max_len);
+
+	return nop->encode_fh(inode, fid->raw, max_len, parent);
 }
 EXPORT_SYMBOL_GPL(exportfs_encode_inode_fh);
 
+/**
+ * exportfs_encode_fh - encode a file handle from dentry
+ * @dentry:  the object to encode
+ * @fid:     where to store the file handle fragment
+ * @max_len: maximum length to store there
+ * @flags:   properties of the requested file handle
+ *
+ * Returns an enum fid_type or a negative errno.
+ */
 int exportfs_encode_fh(struct dentry *dentry, struct fid *fid, int *max_len,
-		int connectable)
+		       int flags)
 {
 	int error;
 	struct dentry *p = NULL;
 	struct inode *inode = dentry->d_inode, *parent = NULL;
 
-	if (connectable && !S_ISDIR(inode->i_mode)) {
+	if ((flags & EXPORT_FH_CONNECTABLE) && !S_ISDIR(inode->i_mode)) {
 		p = dget_parent(dentry);
 		/*
 		 * note that while p might've ceased to be our parent already,
@@ -410,7 +459,7 @@
 		parent = p->d_inode;
 	}
 
-	error = exportfs_encode_inode_fh(inode, fid, max_len, parent);
+	error = exportfs_encode_inode_fh(inode, fid, max_len, parent, flags);
 	dput(p);
 
 	return error;
@@ -429,7 +478,7 @@
 	/*
 	 * Try to get any dentry for the given file handle from the filesystem.
 	 */
-	if (!nop || !nop->fh_to_dentry)
+	if (!exportfs_can_decode_fh(nop))
 		return ERR_PTR(-ESTALE);
 	result = nop->fh_to_dentry(mnt->mnt_sb, fid, fh_len, fileid_type);
 	if (PTR_ERR(result) == -ENOMEM)