These changes (along with corresponding QEMU and Linux kernel changes)
enable a guest to be booted using the x86/HVM direct boot ABI.
QEMU parses the uncompressed kernel binary passed to it via -kernel
to read the ELF Note which contains the address to be loaded. QEMU
then depends on qboot to populate the start_info struct needed by
the direct boot ABI and configure the guest e820 tables before
jumping to the loaded kernel entry.
Signed-off-by: George Kennedy <george.kenn...@oracle.com>
Signed-off-by: Liam Merwick <liam.merw...@oracle.com>
---
fw_cfg.c | 72 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++-
linuxboot.c | 2 +-
main.c | 3 +++
tables.c | 9 ++++++++
4 files changed, 84 insertions(+), 2 deletions(-)
diff --git a/fw_cfg.c b/fw_cfg.c
index f5aac739b921..e13ec20d0e8b 100644
--- a/fw_cfg.c
+++ b/fw_cfg.c
@@ -8,6 +8,10 @@
#include "linuxboot.h"
#include "multiboot.h"
#include "benchmark.h"
+#include "start_info.h"
+
+extern struct hvm_start_info start_info;
+extern inline uint32_t ldl_p(void *p);
struct fw_cfg_file {
uint32_t size;
@@ -184,6 +188,67 @@ static void boot_multiboot_from_fw_cfg(void)
panic();
}
+static void pvh_e820_setup()
+{
+ struct hvm_memmap_table_entry *pvh_e820p;
+ int i, pvh_e820_sz;
+
+ pvh_e820_sz = sizeof(struct hvm_memmap_table_entry) * e820->nr_map;
+
+ pvh_e820p = malloc(pvh_e820_sz);
+ memset(pvh_e820p, 0, pvh_e820_sz);
+
+ for (i = 0; i < e820->nr_map; i++) {
+ pvh_e820p[i].addr = e820->map[i].addr;
+ pvh_e820p[i].size = e820->map[i].size;
+ pvh_e820p[i].type = e820->map[i].type;
+ }
+ start_info.memmap_paddr = (uintptr_t)pvh_e820p;
+ start_info.memmap_entries = e820->nr_map;
+}
+
+void boot_pvh_from_fw_cfg(void)
+{
+ void *kernel_entry;
+ uint32_t sz;
+ struct linuxboot_args args;
+ struct hvm_modlist_entry ramdisk_mod;
+
+ start_info.magic = XEN_HVM_START_MAGIC_VALUE;
+ start_info.version = 1;
+ start_info.flags = 0;
+ start_info.nr_modules = 1;
+ start_info.reserved = 0;
+
+ fw_cfg_select(FW_CFG_CMDLINE_SIZE);
+ args.cmdline_size = fw_cfg_readl_le();
+ args.cmdline_addr = malloc(args.cmdline_size);
+ fw_cfg_read_entry(FW_CFG_CMDLINE_DATA, args.cmdline_addr,
+ args.cmdline_size);
+ start_info.cmdline_paddr = (uintptr_t)args.cmdline_addr;
+
+ /* Use this field for pvhboot. Not used by pvhboot otherwise */
+ fw_cfg_read_entry(FW_CFG_KERNEL_DATA, &ramdisk_mod,
+ sizeof(ramdisk_mod));
+ ramdisk_mod.cmdline_paddr = (uintptr_t)&ramdisk_mod;
+ start_info.modlist_paddr = (uintptr_t)&ramdisk_mod;
+
+ pvh_e820_setup();
+
+ fw_cfg_select(FW_CFG_KERNEL_SIZE);
+ sz = fw_cfg_readl_le();
+ if (!sz)
+ panic();
+
+ fw_cfg_select(FW_CFG_KERNEL_ENTRY);
+ kernel_entry = (void *) fw_cfg_readl_le();
+ asm volatile("movl %0, %%ebx" : : "r"(&start_info));
+
+ asm volatile("jmp *%2" : : "a" (0x2badb002),
+ "b"(&start_info), "c"(kernel_entry));
+ panic();
+}
+
void boot_from_fwcfg(void)
{
struct linuxboot_args args;
@@ -208,8 +273,13 @@ void boot_from_fwcfg(void)
fw_cfg_select(FW_CFG_SETUP_DATA);
fw_cfg_read(args.header, sizeof(args.header));
- if (!parse_bzimage(&args))
+ if (!parse_bzimage(&args)) {
+ uint8_t *header = args.header;
+
+ if (ldl_p(header) == 0x464c457f) /* ELF magic */
+ boot_pvh_from_fw_cfg();
boot_multiboot_from_fw_cfg();
+ }
/* SETUP_DATA already selected */
if (args.setup_size > sizeof(args.header))
diff --git a/linuxboot.c b/linuxboot.c
index a5f1c4fa078d..573052cc0f78 100644
--- a/linuxboot.c
+++ b/linuxboot.c
@@ -12,7 +12,7 @@ static inline uint16_t lduw_p(void *p)
return val;
}
-static inline uint32_t ldl_p(void *p)
+inline uint32_t ldl_p(void *p)
{
uint32_t val;
memcpy(&val, p, 4);
diff --git a/main.c b/main.c
index 699cc1a8e6e7..725d50b94e1e 100644
--- a/main.c
+++ b/main.c
@@ -8,6 +8,9 @@
#include "pflash.h"
#include "pci.h"
#include "benchmark.h"
+#include "start_info.h"
+
+struct hvm_start_info start_info = {0};
static void set_realmode_int(int vec, void *p)
{
diff --git a/tables.c b/tables.c
index 32b2406b9aed..47bef4125d9e 100644
--- a/tables.c
+++ b/tables.c
@@ -2,6 +2,9 @@
#include "stdio.h"
#include "fw_cfg.h"
#include "string.h"
+#include "start_info.h"
+
+extern struct hvm_start_info start_info;
struct loader_cmd {
uint32_t cmd;
@@ -122,6 +125,8 @@ static void do_checksum(char *file, uint32_t offset,
uint32_t start, uint32_t le
p[offset] -= csum8(&p[start], len);
}
+#define RSDP_FILE "etc/acpi/rsdp"
+
void extract_acpi(void)
{
int id = fw_cfg_file_id("etc/table-loader");
@@ -138,6 +143,10 @@ void extract_acpi(void)
struct loader_cmd *s = &script[i];
switch(script[i].cmd) {
case CMD_ALLOC:
+ if (strcmp(s->alloc.file, RSDP_FILE) == 0) {
+ start_info.rsdp_paddr =
+ (uintptr_t)id_to_addr(id);
+ }
do_alloc(s->alloc.file, s->alloc.align, s->alloc.zone);
break;
case CMD_PTR:
--
1.8.3.1
