The start info structure that is defined as part of the x86/HVM direct
boot ABI and used for starting Xen PVH guests would be more versatile if
it also included a way to efficiently pass information about the memory
map to the guest.
That way Xen PVH guests would not be forced to use a hypercall to get the
information and would make it easier for KVM guests to share the PVH
entry point.
---
include/xen/interface/hvm/start_info.h | 34 +++++++++++++++++++++++++++++++---
1 file changed, 31 insertions(+), 3 deletions(-)
diff --git a/include/xen/interface/hvm/start_info.h b/include/xen/interface/hvm/start_info.h
index 6484159..60206bb 100644
--- a/include/xen/interface/hvm/start_info.h
+++ b/include/xen/interface/hvm/start_info.h
@@ -33,7 +33,7 @@
* | magic | Contains the magic value XEN_HVM_START_MAGIC_VALUE
* | | ("xEn3" with the 0x80 bit of the "E" set).
* 4 +----------------+
- * | version | Version of this structure. Current version is 0. New
+ * | version | Version of this structure. Current version is 1. New
* | | versions are guaranteed to be backwards-compatible.
* 8 +----------------+
* | flags | SIF_xxx flags.
@@ -48,6 +48,12 @@
* 32 +----------------+
* | rsdp_paddr | Physical address of the RSDP ACPI data structure.
* 40 +----------------+
+ * | memmap_paddr | Physical address of the memory map. Only present in
+ * | | version 1 and newer of the structure.
+ * 48 +----------------+
+ * | memmap_entries | Number of entries in the memory map table. Only
+ * | | present in version 1 and newer of the structure.
+ * 52 +----------------+
*
* The layout of each entry in the module structure is the following:
*
@@ -62,6 +68,17 @@
* | reserved |
* 32 +----------------+
*
+ * The layout of each entry in the memory map table is as follows and no
+ * padding is used between entries in the array:
+ *
+ * 0 +----------------+
+ * | addr | Base address
+ * 8 +----------------+
+ * | size | Size of mapping
+ * 16 +----------------+
+ * | type | E820_TYPE_xxx
+ * 20 +----------------|
+ *
* The address and sizes are always a 64bit little endian unsigned integer.
*
* NB: Xen on x86 will always try to place all the data below the 4GiB
@@ -86,13 +103,24 @@ struct hvm_start_info {
uint64_t cmdline_paddr; /* Physical address of the command line. */
uint64_t rsdp_paddr; /* Physical address of the RSDP ACPI data */
/* structure. */
-};
+ uint64_t memmap_paddr; /* Physical address of an array of */
+ /* hvm_memmap_table_entry. Only present in */
+ /* Ver 1 or later. For e820 mem map table. */
+ uint32_t memmap_entries; /* Only present in Ver 1 or later. Number of */
+ /* entries in the memmap table. */
+} __attribute__((packed));
struct hvm_modlist_entry {
uint64_t paddr; /* Physical address of the module. */
uint64_t size; /* Size of the module in bytes. */
uint64_t cmdline_paddr; /* Physical address of the command line. */
uint64_t reserved;
-};
+} __attribute__((packed));
+
+struct hvm_memmap_table_entry {
+ uint64_t addr; /* Base address of the memory region */
+ uint64_t size; /* Size of the memory region */
+ uint32_t type; /* E820_TYPE_xxx of the memory region */
+} __attribute__((packed));
#endif /* __XEN_PUBLIC_ARCH_X86_HVM_START_INFO_H__ */
--
1.8.3.1
