[v7][RFC][PATCH 02/13] tools/libxc: introduce hypercall for xc_reserved_device_memory_map

[Tiejun Chen <tiejun.chen@intel.com>]

We will introduce that hypercall xc_reserved_device_memory_map
approach to libxc.

Signed-off-by: Tiejun Chen <tiejun.chen@intel.com>
---
 tools/libxc/include/xenctrl.h |  4 ++++
 tools/libxc/xc_domain.c       | 29 +++++++++++++++++++++++++++++
 2 files changed, 33 insertions(+)

diff --git a/tools/libxc/include/xenctrl.h b/tools/libxc/include/xenctrl.h
index 564e187..b4a60ba 100644
--- a/tools/libxc/include/xenctrl.h
+++ b/tools/libxc/include/xenctrl.h
@@ -1288,6 +1288,10 @@ int xc_domain_set_memory_map(xc_interface *xch,
 int xc_get_machine_memory_map(xc_interface *xch,
                               struct e820entry entries[],
                               uint32_t max_entries);
+
+int xc_reserved_device_memory_map(xc_interface *xch,
+                                  struct xen_mem_reserved_device_memory entries[],
+                                  uint32_t *max_entries);
 #endif
 int xc_domain_set_time_offset(xc_interface *xch,
                               uint32_t domid,
diff --git a/tools/libxc/xc_domain.c b/tools/libxc/xc_domain.c
index a9bcd4a..5f63b6c 100644
--- a/tools/libxc/xc_domain.c
+++ b/tools/libxc/xc_domain.c
@@ -659,6 +659,35 @@ int xc_domain_set_memory_map(xc_interface *xch,
 
     return rc;
 }
+
+int xc_reserved_device_memory_map(xc_interface *xch,
+                                  struct xen_mem_reserved_device_memory entries[],
+                                  uint32_t *max_entries)
+{
+    int rc;
+    struct xen_mem_reserved_device_memory_map memmap = {
+        .nr_entries = *max_entries
+    };
+    DECLARE_HYPERCALL_BOUNCE(entries,
+                             sizeof(struct xen_mem_reserved_device_memory) *
+                             *max_entries, XC_HYPERCALL_BUFFER_BOUNCE_OUT);
+
+    if ( xc_hypercall_bounce_pre(xch, entries) )
+        return -1;
+
+    set_xen_guest_handle(memmap.buffer, entries);
+
+    rc = do_memory_op(xch, XENMEM_reserved_device_memory_map,
+                      &memmap, sizeof(memmap));
+
+    xc_hypercall_bounce_post(xch, entries);
+
+    if ( errno == ENOBUFS )
+        *max_entries = memmap.nr_entries;
+
+    return rc ? rc : memmap.nr_entries;
+}
+
 int xc_get_machine_memory_map(xc_interface *xch,
                               struct e820entry entries[],
                               uint32_t max_entries)
-- 
1.9.1