Changes in kernel/arch/ia32/src/mm/frame.c [9d58539:aaceebc4] in mainline

File:

• kernel/arch/ia32/src/mm/frame.c (modified) (2 diffs)

kernel/arch/ia32/src/mm/frame.c

@@ -47 +47 @@
 
 #define PHYSMEM_LIMIT32  UINT64_C(0x100000000)
+#define PHYSMEM_LIMIT_DMA   UINT64_C(0x1000000)
 
 size_t hardcoded_unmapped_ktext_size = 0;
@@ -91 +92 @@
                                 else
                                         conf = minconf;
-                                zone_create(pfn, count, conf,
-                                    ZONE_AVAILABLE | ZONE_LOWMEM);
+
+                                if ((pfn * PAGE_SIZE) < PHYSMEM_LIMIT_DMA) {
+                                        size_t dma_count = min(
+                                            PHYSMEM_LIMIT_DMA / PAGE_SIZE - pfn,
+                                            count);
+                                        zone_create(pfn, dma_count, conf,
+                                            ZONE_AVAILABLE | ZONE_DMA);
+                                        count -= dma_count;
+                                        pfn += dma_count;
+                                }
+
+                                conf = pfn;
+                                if (count) {
+                                        zone_create(pfn, count, conf,
+                                            ZONE_AVAILABLE | ZONE_LOWMEM);
+                                }
                         } else {
                                 conf = zone_external_conf_alloc(count);
-                                if (conf != 0)
+                                if (conf != 0) {
                                         zone_create(pfn, count, conf,
                                             ZONE_AVAILABLE | ZONE_HIGHMEM);
+                                }
                         }
                 } else if ((e820table[i].type == MEMMAP_MEMORY_ACPI) ||