We split the codes of allocate_bank_memory into two parts,
allocate_domheap_memory and guest_physmap_memory.

One is about allocating guest RAM from heap, which could be re-used later for
allocating static shared memory from heap when host address is not provided.

The other is building up guest P2M mapping.

Signed-off-by: Penny Zheng <penny.zheng@arm.com>
---
 xen/arch/arm/domain_build.c | 93 +++++++++++++++++++++++++++----------
 1 file changed, 68 insertions(+), 25 deletions(-)

diff --git a/xen/arch/arm/domain_build.c b/xen/arch/arm/domain_build.c
index d2b9e60b5c..92763e96fc 100644
--- a/xen/arch/arm/domain_build.c
+++ b/xen/arch/arm/domain_build.c
@@ -390,34 +390,18 @@ static void __init allocate_memory_11(struct domain *d,
     }
 }
 
-static bool __init allocate_bank_memory(struct domain *d,
-                                        struct kernel_info *kinfo,
-                                        gfn_t sgfn,
-                                        paddr_t tot_size)
+static bool __init allocate_domheap_memory(struct domain *d,
+                                           paddr_t tot_size,
+                                           struct meminfo *mem)
 {
-    int res;
     struct page_info *pg;
-    struct membank *bank;
     unsigned int max_order = ~0;
 
-    /*
-     * allocate_bank_memory can be called with a tot_size of zero for
-     * the second memory bank. It is not an error and we can safely
-     * avoid creating a zero-size memory bank.
-     */
-    if ( tot_size == 0 )
-        return true;
-
-    bank = &kinfo->mem.bank[kinfo->mem.nr_banks];
-    bank->start = gfn_to_gaddr(sgfn);
-    bank->size = tot_size;
-
     while ( tot_size > 0 )
     {
         unsigned int order = get_allocation_size(tot_size);
 
         order = min(max_order, order);
-
         pg = alloc_domheap_pages(d, order, 0);
         if ( !pg )
         {
@@ -437,15 +421,74 @@ static bool __init allocate_bank_memory(struct domain *d,
             continue;
         }
 
-        res = guest_physmap_add_page(d, sgfn, page_to_mfn(pg), order);
-        if ( res )
-        {
-            dprintk(XENLOG_ERR, "Failed map pages to DOMU: %d", res);
+        if ( mem->nr_banks == NR_MEM_BANKS )
             return false;
-        }
+
+        mem->bank[mem->nr_banks].start = mfn_to_maddr(page_to_mfn(pg));
+        mem->bank[mem->nr_banks].size = 1UL << (PAGE_SHIFT + order);
+        mem->nr_banks++;
+        tot_size -= (1UL << (PAGE_SHIFT + order));
+    }
+
+    return true;
+}
+
+static int __init guest_physmap_memory(struct domain *d,
+                                       const struct meminfo *mem, gfn_t sgfn)
+{
+    unsigned int i;
+    int res;
+
+    for ( i = 0; i < mem->nr_banks; i++ )
+    {
+        paddr_t size = mem->bank[i].size;
+        unsigned int order = get_order_from_bytes(size);
+
+        /* Size must be power of two */
+        BUG_ON(!size || (size & (size - 1)));
+        res = guest_physmap_add_page(d, sgfn, maddr_to_mfn(mem->bank[i].start),
+                                     order);
+        if ( res )
+            return res;
 
         sgfn = gfn_add(sgfn, 1UL << order);
-        tot_size -= (1ULL << (PAGE_SHIFT + order));
+    }
+
+    return 0;
+}
+
+static bool __init allocate_bank_memory(struct domain *d,
+                                        struct kernel_info *kinfo,
+                                        gfn_t sgfn,
+                                        paddr_t total_size)
+{
+    struct membank *bank;
+    struct meminfo host = {0};
+
+    /*
+     * allocate_bank_memory can be called with a total_size of zero for
+     * the second memory bank. It is not an error and we can safely
+     * avoid creating a zero-size memory bank.
+     */
+    if ( total_size == 0 )
+        return true;
+
+    bank = &kinfo->mem.bank[kinfo->mem.nr_banks];
+    bank->start = gfn_to_gaddr(sgfn);
+    bank->size = total_size;
+
+    if ( !allocate_domheap_memory(d, total_size, &host) )
+    {
+        printk(XENLOG_ERR "Failed to allocate (%"PRIpaddr"MB) pages to %pd\n",
+               total_size >> 20, d);
+        return false;
+    }
+
+    if ( guest_physmap_memory(d, &host, sgfn) )
+    {
+        printk(XENLOG_ERR "Failed to map (%"PRIpaddr"MB) pages to %pd\n",
+               total_size >> 20, d);
+        return false;
     }
 
     kinfo->mem.nr_banks++;
-- 
2.25.1