xen/arm: introduce create_domUs

Call a new function, "create_domUs", from setup_xen to start DomU VMs.

Introduce support for the "xen,domain" compatible node on device tree.
Create new DomU VMs based on the information found on device tree under
"xen,domain". Call construct_domU for each domain.

Introduce a simple global variable named max_init_domid to keep track of
the initial allocated domids. It holds the max domid among the initial
domains.

Move the discard_initial_modules after DomUs have been built.

First create domUs, then start dom0 -- no point in trying to start dom0
when the cpu is busy.

Signed-off-by: Stefano Stabellini <stefanos@xilinx.com>
Acked-by: Jan Beulich <jbeulich@suse.com>
[julien: Add XEN_DOMCTL_CDF_hap_guest]
Reviewed-by: Julien Grall <julien.grall@arm.com>
CC: andrew.cooper3@citrix.com
CC: jbeulich@suse.com

xen/arch/arm/domain_build.c

@@ -7,6 +7,7 @@
 #include <asm/irq.h>
 #include <asm/regs.h>
 #include <xen/errno.h>
+#include <xen/err.h>
 #include <xen/device_tree.h>
 #include <xen/libfdt/libfdt.h>
 #include <xen/guest_access.h>
@@ -2306,6 +2307,51 @@ static int __init construct_domain(struct domain *d, struct kernel_info *kinfo)
     return 0;
 }
 
+static int __init construct_domU(struct domain *d,
+                                 const struct dt_device_node *node)
+{
+    return -ENOSYS;
+}
+
+void __init create_domUs(void)
+{
+    struct dt_device_node *node;
+    const struct dt_device_node *chosen = dt_find_node_by_path("/chosen");
+
+    BUG_ON(chosen == NULL);
+    dt_for_each_child_node(chosen, node)
+    {
+        struct domain *d;
+        struct xen_domctl_createdomain d_cfg = {
+            .arch.gic_version = XEN_DOMCTL_CONFIG_GIC_NATIVE,
+            .arch.nr_spis = 0,
+            .flags = XEN_DOMCTL_CDF_hvm_guest | XEN_DOMCTL_CDF_hap,
+            .max_vcpus = 1,
+            .max_evtchn_port = -1,
+            .max_grant_frames = 64,
+            .max_maptrack_frames = 1024,
+        };
+
+        if ( !dt_device_is_compatible(node, "xen,domain") )
+            continue;
+
+        if ( dt_property_read_bool(node, "vpl011") )
+            d_cfg.arch.nr_spis = GUEST_VPL011_SPI - 32 + 1;
+        dt_property_read_u32(node, "cpus", &d_cfg.max_vcpus);
+
+        d = domain_create(++max_init_domid, &d_cfg, false);
+        if ( IS_ERR(d) )
+            panic("Error creating domain %s", dt_node_name(node));
+
+        d->is_console = true;
+
+        if ( construct_domU(d, node) != 0 )
+            panic("Could not set up domain %s", dt_node_name(node));
+
+        domain_unpause_by_systemcontroller(d);
+    }
+}
+
 int __init construct_dom0(struct domain *d)
 {
     struct kernel_info kinfo = {};
@@ -2356,10 +2402,7 @@ int __init construct_dom0(struct domain *d)
     if ( rc < 0 )
         return rc;
 
-    rc = construct_domain(d, &kinfo);
-    discard_initial_modules();
-
-    return rc;
+    return construct_domain(d, &kinfo);
 }
 
 /*

xen/arch/arm/setup.c

@@ -64,11 +64,14 @@ static unsigned long opt_xenheap_megabytes __initdata;
 integer_param("xenheap_megabytes", opt_xenheap_megabytes);
 #endif
 
+domid_t __read_mostly max_init_domid;
+
 static __used void init_done(void)
 {
     /* Must be done past setting system_state. */
     unregister_init_virtual_region();
 
+    discard_initial_modules();
     free_init_memory();
     startup_cpu_idle_loop();
 }
@@ -964,6 +967,8 @@ void __init start_xen(unsigned long boot_phys_offset,
 
     system_state = SYS_STATE_active;
 
+    create_domUs();
+
     domain_unpause_by_systemcontroller(dom0);
 
     /* Switch on to the dynamically allocated stack for the idle vcpu

xen/include/asm-arm/setup.h

@@ -75,6 +75,8 @@ struct bootinfo {
 
 extern struct bootinfo bootinfo;
 
+extern domid_t max_init_domid;
+
 void arch_init_memory(void);
 
 void copy_from_paddr(void *dst, paddr_t paddr, unsigned long len);
@@ -91,6 +93,7 @@ void acpi_create_efi_mmap_table(struct domain *d,
 int acpi_make_efi_nodes(void *fdt, struct membank tbl_add[]);
 
 int construct_dom0(struct domain *d);
+void create_domUs(void);
 
 void discard_initial_modules(void);
 void dt_unreserved_regions(paddr_t s, paddr_t e,

xen/include/asm-x86/setup.h

@@ -66,4 +66,6 @@ extern bool opt_dom0_shadow;
 #endif
 extern bool dom0_pvh;
 
+#define max_init_domid (0)
+
 #endif