[RFC PATCH 1/2] xen: pass kernel initrd to qemu

[Chunyan Liu <cyliu@suse.com>]

[support xen HVM direct kernel boot]
xen side patch: support 'kernel', 'ramdisk', 'root', 'extra'
in HVM config file, parse config file, pass -kernel, -initrd
and -append parameters to qemu.

[config example]
kernel="/mnt/vmlinuz-3.0.13-0.27-default"
ramdisk="/mnt/initrd-3.0.13-0.27-default"
root="/dev/hda2"
extra="console=tty0 console=ttyS0"
disk=[ 'file:/mnt/images/bjz_04_sles11_sp2/disk0.raw,hda,w', ]

Signed-off-by: Chunyan Liu <cyliu@suse.com>
---
 tools/libxl/libxl_dm.c      | 20 ++++++++++++++++++++
 tools/libxl/libxl_types.idl |  3 +++
 tools/libxl/xl_cmdimpl.c    | 33 +++++++++++++++++++++++++++------
 3 files changed, 50 insertions(+), 6 deletions(-)

diff --git a/tools/libxl/libxl_dm.c b/tools/libxl/libxl_dm.c
index 51ab2bf..133bb56 100644
--- a/tools/libxl/libxl_dm.c
+++ b/tools/libxl/libxl_dm.c
@@ -196,6 +196,16 @@ static char ** libxl__build_device_model_args_old(libxl__gc *gc,
         int nr_set_cpus = 0;
         char *s;
 
+        if (b_info->u.hvm.kernel) {
+            flexarray_vappend(dm_args, "-kernel", b_info->u.hvm.kernel, NULL);
+        }
+        if (b_info->u.hvm.ramdisk) {
+            flexarray_vappend(dm_args, "-initrd", b_info->u.hvm.ramdisk, NULL);
+        }
+        if (b_info->u.hvm.cmdline) {
+            flexarray_vappend(dm_args, "-append", b_info->u.hvm.cmdline, NULL);
+        }
+
         if (b_info->u.hvm.serial) {
             flexarray_vappend(dm_args, "-serial", b_info->u.hvm.serial, NULL);
         }
@@ -479,6 +489,16 @@ static char ** libxl__build_device_model_args_new(libxl__gc *gc,
     if (b_info->type == LIBXL_DOMAIN_TYPE_HVM) {
         int ioemu_nics = 0;
 
+        if (b_info->u.hvm.kernel) {
+            flexarray_vappend(dm_args, "-kernel", b_info->u.hvm.kernel, NULL);
+        }
+        if (b_info->u.hvm.ramdisk) {
+            flexarray_vappend(dm_args, "-initrd", b_info->u.hvm.ramdisk, NULL);
+        }
+        if (b_info->u.hvm.cmdline) {
+            flexarray_vappend(dm_args, "-append", b_info->u.hvm.cmdline, NULL);
+        }
+
         if (b_info->u.hvm.serial) {
             flexarray_vappend(dm_args, "-serial", b_info->u.hvm.serial, NULL);
         }
diff --git a/tools/libxl/libxl_types.idl b/tools/libxl/libxl_types.idl
index 52f1aa9..b8b973b 100644
--- a/tools/libxl/libxl_types.idl
+++ b/tools/libxl/libxl_types.idl
@@ -336,6 +336,9 @@ libxl_domain_build_info = Struct("domain_build_info",[
     ("event_channels",   uint32),
     ("u", KeyedUnion(None, libxl_domain_type, "type",
                 [("hvm", Struct(None, [("firmware",         string),
+                                       ("kernel", string),
+                                       ("cmdline", string),
+                                       ("ramdisk", string),
                                        ("bios",             libxl_bios_type),
                                        ("pae",              libxl_defbool),
                                        ("apic",             libxl_defbool),
diff --git a/tools/libxl/xl_cmdimpl.c b/tools/libxl/xl_cmdimpl.c
index 5195914..efd2474 100644
--- a/tools/libxl/xl_cmdimpl.c
+++ b/tools/libxl/xl_cmdimpl.c
@@ -743,6 +743,8 @@ static void parse_config_data(const char *config_source,
     int pci_permissive = 0;
     int pci_seize = 0;
     int i, e;
+    char *cmdline = NULL;
+    const char *root = NULL, *extra = "";
 
     libxl_domain_create_info *c_info = &d_config->c_info;
     libxl_domain_build_info *b_info = &d_config->b_info;
@@ -1007,9 +1009,31 @@ static void parse_config_data(const char *config_source,
 
     switch(b_info->type) {
     case LIBXL_DOMAIN_TYPE_HVM:
-        if (!xlu_cfg_get_string (config, "kernel", &buf, 0))
-            fprintf(stderr, "WARNING: ignoring \"kernel\" directive for HVM guest. "
-                    "Use \"firmware_override\" instead if you really want a non-default firmware\n");
+        if (!xlu_cfg_get_string (config, "kernel", &buf, 0)) {
+            if (strstr(buf, "hvmloader"))
+                fprintf(stderr, "WARNING: ignoring \"kernel\" directive for HVM guest. "
+                        "Use \"firmware_override\" instead if you really want a non-default firmware\n");
+            else
+                b_info->u.hvm.kernel = strdup(buf);
+        }
+
+        xlu_cfg_get_string (config, "root", &root, 0);
+        xlu_cfg_get_string (config, "extra", &extra, 0);
+
+        if (root) {
+            if (asprintf(&cmdline, "root=%s %s", root, extra) == -1)
+                cmdline = NULL;
+        } else {
+            cmdline = strdup(extra);
+        }
+
+        if ((root || extra) && !cmdline) {
+            fprintf(stderr, "Failed to allocate memory for cmdline\n");
+            exit(1);
+        }
+
+        b_info->u.hvm.cmdline = cmdline;
+        xlu_cfg_replace_string (config, "ramdisk", &b_info->u.hvm.ramdisk, 0);
 
         xlu_cfg_replace_string (config, "firmware_override",
                                 &b_info->u.hvm.firmware, 0);
@@ -1061,9 +1085,6 @@ static void parse_config_data(const char *config_source,
         break;
     case LIBXL_DOMAIN_TYPE_PV:
     {
-        char *cmdline = NULL;
-        const char *root = NULL, *extra = "";
-
         xlu_cfg_replace_string (config, "kernel", &b_info->u.pv.kernel, 0);
 
         xlu_cfg_get_string (config, "root", &root, 0);
-- 
1.8.4.5