disable directio for unaligned reads in Linux
diff --git a/src/os/unix/ngx_files.h b/src/os/unix/ngx_files.h
index 9988bcc..d7a38d9 100644
--- a/src/os/unix/ngx_files.h
+++ b/src/os/unix/ngx_files.h
@@ -222,23 +222,26 @@
#if (NGX_HAVE_O_DIRECT)
-ngx_int_t ngx_directio(ngx_fd_t fd);
-#define ngx_directio_n "fcntl(O_DIRECT)"
+ngx_int_t ngx_directio_on(ngx_fd_t fd);
+#define ngx_directio_on_n "fcntl(O_DIRECT)"
+
+ngx_int_t ngx_directio_off(ngx_fd_t fd);
+#define ngx_directio_off_n "fcntl(!O_DIRECT)"
#elif (NGX_HAVE_F_NOCACHE)
-#define ngx_directio(fd) fcntl(fd, F_NOCACHE, 1)
-#define ngx_directio_n "fcntl(F_NOCACHE)"
+#define ngx_directio_on(fd) fcntl(fd, F_NOCACHE, 1)
+#define ngx_directio_on_n "fcntl(F_NOCACHE, 1)"
#elif (NGX_HAVE_DIRECTIO)
-#define ngx_directio(fd) directio(fd, DIRECTIO_ON)
-#define ngx_directio_n "directio(DIRECTIO_ON)"
+#define ngx_directio_on(fd) directio(fd, DIRECTIO_ON)
+#define ngx_directio_on_n "directio(DIRECTIO_ON)"
#else
-#define ngx_directio(fd) 0
-#define ngx_directio_n "ngx_directio_n"
+#define ngx_directio_on(fd) 0
+#define ngx_directio_on_n "ngx_directio_on_n"
#endif
