[XEN][RFC PATCH v3 12/14] tools/libs/ctrl: Implement new xc interfaces for dt overlay

[Vikram Garhwal <fnu.vikram@xxxxxxxxxx>]

xc_dt_overlay() sends the device tree binary overlay, size of .dtbo and overlay
operation type i.e. add or remove to xen.

Signed-off-by: Vikram Garhwal <fnu.vikram@xxxxxxxxxx>
---
 tools/include/xenctrl.h      |  3 +++
 tools/libs/ctrl/Makefile     |  1 +
 tools/libs/ctrl/xc_overlay.c | 51 ++++++++++++++++++++++++++++++++++++
 3 files changed, 55 insertions(+)
 create mode 100644 tools/libs/ctrl/xc_overlay.c

diff --git a/tools/include/xenctrl.h b/tools/include/xenctrl.h
index 95bd5eca67..b7552d0d9c 100644
--- a/tools/include/xenctrl.h
+++ b/tools/include/xenctrl.h
@@ -2629,6 +2629,9 @@ int xc_livepatch_replace(xc_interface *xch, char *name, 
uint32_t timeout, uint32
 int xc_domain_cacheflush(xc_interface *xch, uint32_t domid,
                          xen_pfn_t start_pfn, xen_pfn_t nr_pfns);
 
+int xc_dt_overlay(xc_interface *xch, void *overlay_fdt, int overlay_fdt_size,
+                  uint8_t overlay_op);
+
 /* Compat shims */
 #include "xenctrl_compat.h"
 
diff --git a/tools/libs/ctrl/Makefile b/tools/libs/ctrl/Makefile
index ef7362327f..848a8737c7 100644
--- a/tools/libs/ctrl/Makefile
+++ b/tools/libs/ctrl/Makefile
@@ -3,6 +3,7 @@ include $(XEN_ROOT)/tools/Rules.mk
 
 SRCS-y       += xc_altp2m.c
 SRCS-y       += xc_cpupool.c
+SRCS-y       += xc_overlay.c
 SRCS-y       += xc_domain.c
 SRCS-y       += xc_evtchn.c
 SRCS-y       += xc_gnttab.c
diff --git a/tools/libs/ctrl/xc_overlay.c b/tools/libs/ctrl/xc_overlay.c
new file mode 100644
index 0000000000..8fe780d75a
--- /dev/null
+++ b/tools/libs/ctrl/xc_overlay.c
@@ -0,0 +1,51 @@
+/*
+ *
+ * Overlay control functions.
+ * Copyright (C) 2021 Xilinx Inc.
+ * Author Vikram Garhwal <fnu.vikram@xxxxxxxxxx>
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation;
+ * version 2.1 of the License.
+ *
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library; If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#include "xc_bitops.h"
+#include "xc_private.h"
+#include <xen/hvm/hvm_op.h>
+#include <libfdt.h>
+
+int xc_dt_overlay(xc_interface *xch, void *overlay_fdt, int overlay_fdt_size,
+                  uint8_t overlay_op)
+{
+    int err;
+    DECLARE_SYSCTL;
+
+    DECLARE_HYPERCALL_BOUNCE(overlay_fdt, overlay_fdt_size,
+                        XC_HYPERCALL_BUFFER_BOUNCE_IN);
+
+    if ( (err = xc_hypercall_bounce_pre(xch, overlay_fdt)) )
+        goto err;
+
+    sysctl.cmd = XEN_SYSCTL_dt_overlay;
+    sysctl.u.dt_overlay.overlay_op = overlay_op;
+    sysctl.u.dt_overlay.overlay_fdt_size = overlay_fdt_size;
+
+    set_xen_guest_handle(sysctl.u.dt_overlay.overlay_fdt, overlay_fdt);
+
+    if ( (err = do_sysctl(xch, &sysctl)) != 0 )
+        PERROR("%s failed\n", __func__);
+
+err:
+    xc_hypercall_bounce_post(xch, overlay_fdt);
+
+    return err;
+}
-- 
2.17.1