Libguestfs - Jan 2015 - [PATCH] aarch64: appliance: Use AAVMF (UEFI) if available for running the appliance.

From: "Richard W.M. Jones" <rjones@redhat.com>

AAVMF is an open source UEFI implementation for aarch64 based on OVMF.
As aarch64 is heading for requiring UEFI even inside guests, if the
AAVMF firmware is installed on the host, use it as a hint that we
should boot the guest using AAVMF instead of the default "empty
machine".

Note this requires very recent AAVMF, libvirt, qemu.  However that's
OK since it's only applicable to aarch64.  On non-aarch64, this patch
does nothing.

Thanks: Laszlo Ersek for a lot of help getting this right.
---
 src/appliance.c        | 66 +++++++++++++++++++++++++++++++++++++++++++++++++-
 src/guestfs-internal.h |  1 +
 src/launch-direct.c    | 14 +++++++++++
 src/launch-libvirt.c   | 25 +++++++++++++++++++
 4 files changed, 105 insertions(+), 1 deletion(-)

diff --git a/src/appliance.c b/src/appliance.c
index d7aa6b1..5fa47f2 100644
--- a/src/appliance.c
+++ b/src/appliance.c
@@ -1,5 +1,5 @@
 /* libguestfs
- * Copyright (C) 2010-2012 Red Hat Inc.
+ * Copyright (C) 2010-2014 Red Hat Inc.
  *
  * This library is free software; you can redistribute it and/or
  * modify it under the terms of the GNU Lesser General Public
@@ -459,3 +459,67 @@ dir_contains_files (const char *dir, ...)
   va_end (args);
   return 1;
 }
+
+#ifdef __aarch64__
+
+#define AAVMF_DIR "/usr/share/AAVMF"
+
+/* Return the location of firmware needed to boot the appliance.  This
+ * is aarch64 only currently, since that's the only architecture where
+ * UEFI is mandatory (and that only for RHEL).
+ *
+ * '*code' is initialized with the path to the read-only UEFI code
+ * file.  '*vars' is initialized with the path to a copy of the UEFI
+ * vars file (which is cleaned up automatically on exit).
+ *
+ * If *code == *vars == NULL then no UEFI firmware is available.
+ *
+ * '*code' and '*vars' should be freed by the caller.
+ *
+ * If the function returns -1 then there was a real error which should
+ * cause appliance building to fail (no UEFI firmware is not an
+ * error).
+ */
+int
+guestfs___get_uefi (guestfs_h *g, char **code, char **vars)
+{
+  if (access (AAVMF_DIR "/AAVMF_CODE.fd", R_OK) == 0 &&
+      access (AAVMF_DIR "/AAVMF_VARS.fd", R_OK) == 0) {
+    CLEANUP_CMD_CLOSE struct command *copycmd = guestfs___new_command (g);
+    char *varst;
+    int r;
+
+    /* Make a copy of AAVMF_VARS.fd.  You can't just map it into the
+     * address space read-only as that triggers a different path
+     * inside UEFI.
+     */
+    varst = safe_asprintf (g, "%s/AAVMF_VARS.fd.%d", g->tmpdir,
++g->unique);
+    guestfs___cmd_add_arg (copycmd, "cp");
+    guestfs___cmd_add_arg (copycmd, AAVMF_DIR "/AAVMF_VARS.fd");
+    guestfs___cmd_add_arg (copycmd, varst);
+    r = guestfs___cmd_run (copycmd);
+    if (r == -1 || !WIFEXITED (r) || WEXITSTATUS (r) != 0) {
+      free (varst);
+      return -1;
+    }
+
+    /* Caller frees. */
+    *code = safe_strdup (g, AAVMF_DIR "/AAVMF_CODE.fd");
+    *vars = varst;
+    return 0;
+  }
+
+  *code = *vars = NULL;
+  return 0;
+}
+
+#else /* !__aarch64__ */
+
+int
+guestfs___get_uefi (guestfs_h *g, char **code, char **vars)
+{
+  *code = *vars = NULL;
+  return 0;
+}
+
+#endif /* !__aarch64__ */
diff --git a/src/guestfs-internal.h b/src/guestfs-internal.h
index 58f657c..d438be3 100644
--- a/src/guestfs-internal.h
+++ b/src/guestfs-internal.h
@@ -752,6 +752,7 @@ extern const char *guestfs___drive_protocol_to_string (enum
drive_protocol proto
 
 /* appliance.c */
 extern int guestfs___build_appliance (guestfs_h *g, char **kernel, char **dtb,
char **initrd, char **appliance);
+extern int guestfs___get_uefi (guestfs_h *g, char **code, char **vars);
 
 /* launch.c */
 extern int64_t guestfs___timeval_diff (const struct timeval *x, const struct
timeval *y);
diff --git a/src/launch-direct.c b/src/launch-direct.c
index b74f689..e6ed54a 100644
--- a/src/launch-direct.c
+++ b/src/launch-direct.c
@@ -236,6 +236,7 @@ launch_direct (guestfs_h *g, void *datav, const char *arg)
   int sv[2];
   char guestfsd_sock[256];
   struct sockaddr_un addr;
+  CLEANUP_FREE char *uefi_code = NULL, *uefi_vars = NULL;
   CLEANUP_FREE char *kernel = NULL, *dtb = NULL,
     *initrd = NULL, *appliance = NULL;
   int has_appliance_drive;
@@ -444,6 +445,19 @@ launch_direct (guestfs_h *g, void *datav, const char *arg)
     ADD_CMDLINE ("kvm-pit.lost_tick_policy=discard");
   }
 
+  /* UEFI (firmware) if required. */
+  if (guestfs___get_uefi (g, &uefi_code, &uefi_vars) == -1)
+    goto cleanup0;
+  if (uefi_code) {
+    ADD_CMDLINE ("-drive");
+    ADD_CMDLINE_PRINTF ("if=pflash,format=raw,file=%s,readonly",
uefi_code);
+    if (uefi_vars) {
+      ADD_CMDLINE ("-drive");
+      ADD_CMDLINE_PRINTF ("if=pflash,format=raw,file=%s", uefi_vars);
+    }
+  }
+
+  /* Kernel, DTB and initrd. */
   ADD_CMDLINE ("-kernel");
   ADD_CMDLINE (kernel);
   if (dtb) {
diff --git a/src/launch-libvirt.c b/src/launch-libvirt.c
index 899742f..7a57f30 100644
--- a/src/launch-libvirt.c
+++ b/src/launch-libvirt.c
@@ -134,6 +134,8 @@ struct backend_libvirt_data {
   unsigned long qemu_version;   /* qemu version (from libvirt) */
   struct secret *secrets;       /* list of secrets */
   size_t nr_secrets;
+  char *uefi_code;		/* UEFI (firmware) code and variables. */
+  char *uefi_vars;
 };
 
 /* Parameters passed to construct_libvirt_xml and subfunctions.  We
@@ -357,6 +359,10 @@ launch_libvirt (guestfs_h *g, void *datav, const char
*libvirt_uri)
   if (parse_capabilities (g, capabilities_xml, data) == -1)
     goto cleanup;
 
+  /* UEFI code and variables, on architectures where that is required. */
+  if (guestfs___get_uefi (g, &data->uefi_code, &data->uefi_vars)
== -1)
+    goto cleanup;
+
   /* Misc backend settings. */
   guestfs_push_error_handler (g, NULL, NULL);
   free (data->selinux_label);
@@ -1145,6 +1151,20 @@ construct_libvirt_xml_boot (guestfs_h *g,
       string ("hvm");
     } end_element ();
 
+    if (params->data->uefi_code) {
+      start_element ("loader") {
+	attribute ("readonly", "yes");
+	attribute ("type", "pflash");
+	string (params->data->uefi_code);
+      } end_element ();
+
+      if (params->data->uefi_vars) {
+	start_element ("nvram") {
+	  string (params->data->uefi_vars);
+	} end_element ();
+      }
+    }
+
     start_element ("kernel") {
       string (params->kernel);
     } end_element ();
@@ -1984,6 +2004,11 @@ shutdown_libvirt (guestfs_h *g, void *datav, int
check_for_errors)
   data->secrets = NULL;
   data->nr_secrets = 0;
 
+  free (data->uefi_code);
+  data->uefi_code = NULL;
+  free (data->uefi_vars);
+  data->uefi_vars = NULL;
+
   return ret;
 }
 
-- 
1.8.3.1