xen: check memory area against e820 map

[firefly-linux-kernel-4.4.55.git] / arch / x86 / xen / setup.c

diff --git a/arch/x86/xen/setup.c b/arch/x86/xen/setup.c
index 87251b4c2e303d0c18a37c9e0b82445ec373a150..99ef82cc4edc3bd8c6e2b2674b0ce1c565998398 100644 (file)
--- a/arch/x86/xen/setup.c
+++ b/arch/x86/xen/setup.c
@@ -573,6 +573,29 @@ static unsigned long __init xen_count_remap_pages(unsigned long max_pfn)
        return extra;
 }
 
+bool __init xen_is_e820_reserved(phys_addr_t start, phys_addr_t size)
+{
+       struct e820entry *entry;
+       unsigned mapcnt;
+       phys_addr_t end;
+
+       if (!size)
+               return false;
+
+       end = start + size;
+       entry = xen_e820_map;
+
+       for (mapcnt = 0; mapcnt < xen_e820_map_entries; mapcnt++) {
+               if (entry->type == E820_RAM && entry->addr <= start &&
+                   (entry->addr + entry->size) >= end)
+                       return false;
+
+               entry++;
+       }
+
+       return true;
+}
+
 /*
  * Reserve Xen mfn_list.
  * See comment above "struct start_info" in <xen/interface/xen.h>