[PATCH v4 2/9] xen/arm: implement domU extended regions

[Stefano Stabellini <sstabellini@kernel.org>]

From: Stefano Stabellini <stefano.stabellini@xilinx.com>

Implement extended regions for dom0less domUs. The implementation is
based on the libxl implementation.

Signed-off-by: Stefano Stabellini <stefano.stabellini@xilinx.com>
---
 xen/arch/arm/domain_build.c | 42 ++++++++++++++++++++++++++++++++++---
 1 file changed, 39 insertions(+), 3 deletions(-)

diff --git a/xen/arch/arm/domain_build.c b/xen/arch/arm/domain_build.c
index 8be01678de..b6189b935d 100644
--- a/xen/arch/arm/domain_build.c
+++ b/xen/arch/arm/domain_build.c
@@ -1324,6 +1324,35 @@ out:
     return res;
 }
 
+#define ALIGN_UP_TO_2MB(x)   (((x) + MB(2) - 1) & (~(MB(2) - 1)))
+
+static int __init find_domU_holes(const struct kernel_info *kinfo,
+                                  struct meminfo *ext_regions)
+{
+    unsigned int i;
+    uint64_t bankend[GUEST_RAM_BANKS];
+    const uint64_t bankbase[] = GUEST_RAM_BANK_BASES;
+    const uint64_t banksize[] = GUEST_RAM_BANK_SIZES;
+
+    for ( i = 0; i < GUEST_RAM_BANKS; i++ )
+    {
+        ext_regions->bank[ext_regions->nr_banks].start =
+            ALIGN_UP_TO_2MB(bankbase[i] + kinfo->mem.bank[i].size);
+
+        bankend[i] = ~0ULL >> (64 - p2m_ipa_bits);
+        bankend[i] = min(bankend[i], bankbase[i] + banksize[i] - 1);
+        if (bankend[i] > ext_regions->bank[ext_regions->nr_banks].start)
+            ext_regions->bank[ext_regions->nr_banks].size =
+                bankend[i] - ext_regions->bank[ext_regions->nr_banks].start + 1;
+
+        /* 64MB is the minimum size of an extended region */
+        if ( ext_regions->bank[ext_regions->nr_banks].size < MB(64) )
+            continue;
+        ext_regions->nr_banks++;
+    }
+    return 0;
+}
+
 static int __init make_hypervisor_node(struct domain *d,
                                        const struct kernel_info *kinfo,
                                        int addrcells, int sizecells)
@@ -1374,10 +1403,17 @@ static int __init make_hypervisor_node(struct domain *d,
         if ( !ext_regions )
             return -ENOMEM;
 
-        if ( !is_iommu_enabled(d) )
-            res = find_unallocated_memory(kinfo, ext_regions);
+        if ( is_domain_direct_mapped(d) )
+        {
+            if ( !is_iommu_enabled(d) )
+                res = find_unallocated_memory(kinfo, ext_regions);
+            else
+                res = find_memory_holes(kinfo, ext_regions);
+        }
         else
-            res = find_memory_holes(kinfo, ext_regions);
+        {
+            res = find_domU_holes(kinfo, ext_regions);
+        }
 
         if ( res )
             printk(XENLOG_WARNING "Failed to allocate extended regions\n");
-- 
2.25.1