[PATCH v5 05/12] x86/hyperlaunch: locate dom0 kernel with hyperlaunch

[Alejandro Vallejo <agarciav@xxxxxxx>]

From: "Daniel P. Smith" <dpsmith@xxxxxxxxxxxxxxxxxxxx>

Look for a subnode of type `multiboot,kernel` within a domain node. If
found, locate it using the multiboot module helper to generically ensure
it lives in the module list. If the bootargs property is present and
there was not an MB1 string, then use the command line from the device
tree definition.

Signed-off-by: Daniel P. Smith <dpsmith@xxxxxxxxxxxxxxxxxxxx>
Signed-off-by: Jason Andryuk <jason.andryuk@xxxxxxx>
Signed-off-by: Alejandro Vallejo <agarciav@xxxxxxx>
---
v5:
  * Add domain name to the error path on no-kernel.
---
 xen/arch/x86/setup.c            |  1 +
 xen/common/domain-builder/fdt.c | 64 +++++++++++++++++++++++++++++++--
 2 files changed, 62 insertions(+), 3 deletions(-)

diff --git a/xen/arch/x86/setup.c b/xen/arch/x86/setup.c
index bd13d9d196..7e756302ae 100644
--- a/xen/arch/x86/setup.c
+++ b/xen/arch/x86/setup.c
@@ -1290,6 +1290,7 @@ void asmlinkage __init noreturn __start_xen(void)
         i = first_boot_module_index(bi, BOOTMOD_UNKNOWN);
         bi->mods[i].type = BOOTMOD_KERNEL;
         bi->domains[0].kernel = &bi->mods[i];
+        bi->nr_domains = 1;
         bi->hyperlaunch_enabled = false;
     }
 
diff --git a/xen/common/domain-builder/fdt.c b/xen/common/domain-builder/fdt.c
index 11f0436e85..662c715483 100644
--- a/xen/common/domain-builder/fdt.c
+++ b/xen/common/domain-builder/fdt.c
@@ -99,9 +99,9 @@ static int __init fdt_prop_as_reg(const struct fdt_property 
*prop,
  * @return              -EINVAL on malformed nodes, otherwise
  *                      index inside `bi->mods`
  */
-int __init fdt_read_multiboot_module(const void *fdt, int node,
-                                     int address_cells, int size_cells,
-                                     struct boot_info *bi)
+static int __init fdt_read_multiboot_module(const void *fdt, int node,
+                                            int address_cells, int size_cells,
+                                            struct boot_info *bi)
 {
     const struct fdt_property *prop;
     uint64_t addr, size;
@@ -185,6 +185,52 @@ int __init fdt_read_multiboot_module(const void *fdt, int 
node,
     return idx;
 }
 
+static int __init process_domain_node(
+    struct boot_info *bi, const void *fdt, int dom_node)
+{
+    int node;
+    struct boot_domain *bd = &bi->domains[bi->nr_domains];
+    const char *name = fdt_get_name(fdt, dom_node, NULL) ?: "unknown";
+    int address_cells = fdt_address_cells(fdt, dom_node);
+    int size_cells = fdt_size_cells(fdt, dom_node);
+
+    fdt_for_each_subnode(node, fdt, dom_node)
+    {
+        if ( !fdt_node_check_compatible(fdt, node, "multiboot,kernel") )
+        {
+            int idx;
+
+            if ( bd->kernel )
+            {
+                printk(XENLOG_WARNING
+                       "  duplicate kernel for domain %s\n", name);
+                continue;
+            }
+
+            idx = fdt_read_multiboot_module(fdt, node, address_cells,
+                                            size_cells, bi);
+            if ( idx < 0 )
+            {
+                printk(XENLOG_ERR
+                       "  failed processing kernel for domain %s\n", name);
+                return idx;
+            }
+
+            printk(XENLOG_INFO "  kernel: multiboot-index=%d\n", idx);
+            bi->mods[idx].type = BOOTMOD_KERNEL;
+            bd->kernel = &bi->mods[idx];
+        }
+    }
+
+    if ( !bd->kernel )
+    {
+        printk(XENLOG_ERR "error: no kernel assigned to domain %s\n", name);
+        return -ENODATA;
+    }
+
+    return 0;
+}
+
 static int __init find_hyperlaunch_node(const void *fdt)
 {
     int hv_node = fdt_path_offset(fdt, "/chosen/hypervisor");
@@ -248,8 +294,20 @@ int __init walk_hyperlaunch_fdt(struct boot_info *bi)
 
     fdt_for_each_subnode(node, fdt, hv_node)
     {
+        if ( bi->nr_domains >= MAX_NR_BOOTDOMS )
+        {
+            printk(XENLOG_WARNING "warning: only creating first %u domains\n",
+                   MAX_NR_BOOTDOMS);
+            break;
+        }
+
         if ( !fdt_node_check_compatible(fdt, node, "xen,domain") )
+        {
+            if ( (ret = process_domain_node(bi, fdt, node)) < 0 )
+                break;
+
             bi->nr_domains++;
+        }
     }
 
     /* Until multi-domain construction is added, throw an error */
-- 
2.43.0