[PATCH 8/9] xen/arm: check `xen,static-mem` property during domain construction

[Penny Zheng <penny.zheng@xxxxxxx>]

This commit checks `xen,static-mem` device tree property in /domUx node,
to determine whether domain is on Static Allocation, when constructing
domain during boot-up.

Right now, the implementation of allocate_static_memory is missing, and
will be introduced later. It just BUG() out at the moment.

And if the `memory` property and `xen,static-mem` are both set, it shall
be verified that if the memory size defined in both is consistent.

Signed-off-by: Penny Zheng <penny.zheng@xxxxxxx>
---
changes v2:
- remove parsing procedure here
- check the consistency when `xen,static-mem` and `memory` are both defined
---
 xen/arch/arm/domain_build.c | 37 +++++++++++++++++++++++++++++++------
 1 file changed, 31 insertions(+), 6 deletions(-)

diff --git a/xen/arch/arm/domain_build.c b/xen/arch/arm/domain_build.c
index 282416e74d..4166d7993c 100644
--- a/xen/arch/arm/domain_build.c
+++ b/xen/arch/arm/domain_build.c
@@ -2424,23 +2424,47 @@ static int __init construct_domU(struct domain *d,
 {
     struct kernel_info kinfo = {};
     int rc;
-    u64 mem;
+    u64 mem, static_mem_size = 0;
+    const struct dt_property *prop;
+    bool static_mem = false;
+
+    d->max_pages = ~0U;
+    /*
+     * Guest RAM could be of static memory from static allocation,
+     * which will be specified through "xen,static-mem" phandle.
+     */
+    prop = dt_find_property(node, "xen,static-mem", NULL);
+    if ( prop )
+    {
+        static_mem = true;
+        /* static_mem_size = allocate_static_memory(...); */
+        BUG();
+    }
 
     rc = dt_property_read_u64(node, "memory", &mem);
-    if ( !rc )
+    if ( !static_mem && !rc )
     {
         printk("Error building DomU: cannot read \"memory\" property\n");
         return -EINVAL;
+    } else if ( rc && static_mem )
+    {
+        if ( static_mem_size != mem * SZ_1K )
+        {
+            printk("Memory size in \"memory\" property isn't consistent with"
+                   "the ones defined in \"xen,static-mem\".\n");
+            return -EINVAL;
+        }
     }
-    kinfo.unassigned_mem = (paddr_t)mem * SZ_1K;
+    kinfo.unassigned_mem = static_mem ? 0 : (paddr_t)mem * SZ_1K;
 
-    printk("*** LOADING DOMU cpus=%u memory=%"PRIx64"KB ***\n", d->max_vcpus, 
mem);
+    printk("*** LOADING DOMU cpus=%u memory=%"PRIx64"KB ***\n",
+            d->max_vcpus,
+            static_mem ? static_mem_size : (kinfo.unassigned_mem) >> 10);
 
     kinfo.vpl011 = dt_property_read_bool(node, "vpl011");
 
     if ( vcpu_create(d, 0) == NULL )
         return -ENOMEM;
-    d->max_pages = ~0U;
 
     kinfo.d = d;
 
@@ -2452,7 +2476,8 @@ static int __init construct_domU(struct domain *d,
     /* type must be set before allocate memory */
     d->arch.type = kinfo.type;
 #endif
-    allocate_memory(d, &kinfo);
+    if ( !static_mem )
+        allocate_memory(d, &kinfo);
 
     rc = prepare_dtb_domU(d, &kinfo);
     if ( rc < 0 )
-- 
2.25.1