smb3_fs_context_fullpath
char *smb3_fs_context_fullpath(const struct smb3_fs_context *ctx, char dirsep);
full_path = smb3_fs_context_fullpath(ctx, CIFS_DIR_SEP(cifs_sb));
ctx->source = smb3_fs_context_fullpath(ctx, '/');
ctx->source = smb3_fs_context_fullpath(ctx, '/');