[RFC PATCH v2 05/16] libxl: Load guest BIOS from file

[Anthony PERARD <anthony.perard@citrix.com>]

The path to the BIOS blob can be override by the xl's bios_override option,
or provided by u.hvm.bios_filename in the domain_build_info struct by other
libxl user.

Signed-off-by: Anthony PERARD <anthony.perard@citrix.com>
---
 tools/libxl/libxl_dom.c     | 66 +++++++++++++++++++++++++++++++++++++++++++++
 tools/libxl/libxl_types.idl |  1 +
 tools/libxl/xl_cmdimpl.c    | 11 +++++---
 3 files changed, 75 insertions(+), 3 deletions(-)

diff --git a/tools/libxl/libxl_dom.c b/tools/libxl/libxl_dom.c
index b40d744..27a0021 100644
--- a/tools/libxl/libxl_dom.c
+++ b/tools/libxl/libxl_dom.c
@@ -858,6 +858,42 @@ err:
     return ret;
 }
 
+static const char *seabios_path(libxl__gc *gc)
+{
+    return SEABIOS_PATH;
+}
+
+static const char *ovmf_path(libxl__gc *gc)
+{
+    return OVMF_PATH;
+}
+
+static int libxl__load_hvm_firmware_module(libxl__gc *gc,
+                                           const char *filename,
+                                           const char *what,
+                                           struct xc_hvm_firmware_module *m)
+{
+    int datalen = 0;
+    void *data = NULL;
+    int e;
+
+    LOG(DEBUG, "Loading %s: %s", what, filename);
+    e = libxl_read_file_contents(CTX, filename, &data, &datalen);
+    if (e) {
+        LOGEV(ERROR, e, "failed to read %s file %s",
+              what,
+              filename);
+        return ERROR_FAIL;
+    }
+    libxl__ptr_add(gc, data);
+    if (datalen) {
+        /* Only accept non-empty files */
+        m->data = data;
+        m->length = (uint32_t)datalen;
+    }
+    return 0;
+}
+
 static int libxl__domain_firmware(libxl__gc *gc,
                                   libxl_domain_build_info *info,
                                   struct xc_dom_image *dom)
@@ -910,6 +946,36 @@ static int libxl__domain_firmware(libxl__gc *gc,
         goto out;
     }
 
+    if (info->device_model_version != LIBXL_DEVICE_MODEL_VERSION_NONE) {
+        const char *bios_filename;
+        // Look for BIOS and load it
+        if (info->u.hvm.bios_filename) {
+            bios_filename = info->u.hvm.bios_filename;
+        } else {
+            switch (info->u.hvm.bios)
+            {
+            case LIBXL_BIOS_TYPE_ROMBIOS:
+                bios_filename = libxl__abs_path(gc, "rombios.bin",
+                                                libxl__xenfirmwaredir_path());
+                break;
+            case LIBXL_BIOS_TYPE_SEABIOS:
+                bios_filename = seabios_path(gc);
+                break;
+            case LIBXL_BIOS_TYPE_OVMF:
+                bios_filename = ovmf_path(gc);
+                break;
+            default:
+                LOG(ERROR, "invalid bios version %d", info->u.hvm.bios);
+                rc = ERROR_FAIL;
+                goto out;
+            }
+        }
+
+        rc = libxl__load_hvm_firmware_module(gc, bios_filename, "BIOS",
+                                             &dom->bios_module);
+        if (rc) goto out;
+    }
+
     if (info->u.hvm.smbios_firmware) {
         data = NULL;
         e = libxl_read_file_contents(ctx, info->u.hvm.smbios_firmware,
diff --git a/tools/libxl/libxl_types.idl b/tools/libxl/libxl_types.idl
index 082fed8..a3fbcab 100644
--- a/tools/libxl/libxl_types.idl
+++ b/tools/libxl/libxl_types.idl
@@ -468,6 +468,7 @@ libxl_domain_build_info = Struct("domain_build_info",[
     ("u", KeyedUnion(None, libxl_domain_type, "type",
                 [("hvm", Struct(None, [("firmware",         string),
                                        ("bios",             libxl_bios_type),
+                                       ("bios_filename",    string),
                                        ("pae",              libxl_defbool),
                                        ("apic",             libxl_defbool),
                                        ("acpi",             libxl_defbool),
diff --git a/tools/libxl/xl_cmdimpl.c b/tools/libxl/xl_cmdimpl.c
index 840d73f..27d7c25 100644
--- a/tools/libxl/xl_cmdimpl.c
+++ b/tools/libxl/xl_cmdimpl.c
@@ -1500,12 +1500,17 @@ static void parse_config_data(const char *config_source,
 
         xlu_cfg_replace_string (config, "firmware_override",
                                 &b_info->u.hvm.firmware, 0);
-        if (!xlu_cfg_get_string(config, "bios", &buf, 0) &&
-            libxl_bios_type_from_string(buf, &b_info->u.hvm.bios)) {
+        xlu_cfg_replace_string (config, "bios_override",
+                                &b_info->u.hvm.bios_filename, 0);
+        if (!xlu_cfg_get_string(config, "bios", &buf, 0)) {
+            if (libxl_bios_type_from_string(buf, &b_info->u.hvm.bios)) {
                 fprintf(stderr, "ERROR: invalid value \"%s\" for \"bios\"\n",
                     buf);
                 exit (1);
-        }
+            }
+        } else if (b_info->u.hvm.bios_filename)
+            fprintf(stderr, "WARNING: "
+                    "bios_override given without specific bios name\n");
 
         xlu_cfg_get_defbool(config, "pae", &b_info->u.hvm.pae, 0);
         xlu_cfg_get_defbool(config, "apic", &b_info->u.hvm.apic, 0);
-- 
Anthony PERARD