Add API to create memory mapping list

The memory mapping list stores virtual address and physical address mapping.
The virtual address and physical address are contiguous in the mapping.
The folloing patch will use this information to create PT_LOAD in the vmcore.

Signed-off-by: Wen Congyang <wency@cn.fujitsu.com>
Signed-off-by: Luiz Capitulino <lcapitulino@redhat.com>

1 files changed, 166 insertions, 0 deletions

diff --git a/memory_mapping.c b/memory_mapping.c
new file mode 100644
index 0000000..718f271
--- /dev/null
+++ b/memory_mapping.c
@@ -0,0 +1,166 @@
+/*
+ * QEMU memory mapping
+ *
+ * Copyright Fujitsu, Corp. 2011, 2012
+ *
+ * Authors:
+ *     Wen Congyang <wency@cn.fujitsu.com>
+ *
+ * This work is licensed under the terms of the GNU GPL, version 2. See
+ * the COPYING file in the top-level directory.
+ *
+ */
+
+#include "cpu.h"
+#include "cpu-all.h"
+#include "memory_mapping.h"
+
+static void memory_mapping_list_add_mapping_sorted(MemoryMappingList *list,
+                                                   MemoryMapping *mapping)
+{
+    MemoryMapping *p;
+
+    QTAILQ_FOREACH(p, &list->head, next) {
+        if (p->phys_addr >= mapping->phys_addr) {
+            QTAILQ_INSERT_BEFORE(p, mapping, next);
+            return;
+        }
+    }
+    QTAILQ_INSERT_TAIL(&list->head, mapping, next);
+}
+
+static void create_new_memory_mapping(MemoryMappingList *list,
+                                      target_phys_addr_t phys_addr,
+                                      target_phys_addr_t virt_addr,
+                                      ram_addr_t length)
+{
+    MemoryMapping *memory_mapping;
+
+    memory_mapping = g_malloc(sizeof(MemoryMapping));
+    memory_mapping->phys_addr = phys_addr;
+    memory_mapping->virt_addr = virt_addr;
+    memory_mapping->length = length;
+    list->last_mapping = memory_mapping;
+    list->num++;
+    memory_mapping_list_add_mapping_sorted(list, memory_mapping);
+}
+
+static inline bool mapping_contiguous(MemoryMapping *map,
+                                      target_phys_addr_t phys_addr,
+                                      target_phys_addr_t virt_addr)
+{
+    return phys_addr == map->phys_addr + map->length &&
+           virt_addr == map->virt_addr + map->length;
+}
+
+/*
+ * [map->phys_addr, map->phys_addr + map->length) and
+ * [phys_addr, phys_addr + length) have intersection?
+ */
+static inline bool mapping_have_same_region(MemoryMapping *map,
+                                            target_phys_addr_t phys_addr,
+                                            ram_addr_t length)
+{
+    return !(phys_addr + length < map->phys_addr ||
+             phys_addr >= map->phys_addr + map->length);
+}
+
+/*
+ * [map->phys_addr, map->phys_addr + map->length) and
+ * [phys_addr, phys_addr + length) have intersection. The virtual address in the
+ * intersection are the same?
+ */
+static inline bool mapping_conflict(MemoryMapping *map,
+                                    target_phys_addr_t phys_addr,
+                                    target_phys_addr_t virt_addr)
+{
+    return virt_addr - map->virt_addr != phys_addr - map->phys_addr;
+}
+
+/*
+ * [map->virt_addr, map->virt_addr + map->length) and
+ * [virt_addr, virt_addr + length) have intersection. And the physical address
+ * in the intersection are the same.
+ */
+static inline void mapping_merge(MemoryMapping *map,
+                                 target_phys_addr_t virt_addr,
+                                 ram_addr_t length)
+{
+    if (virt_addr < map->virt_addr) {
+        map->length += map->virt_addr - virt_addr;
+        map->virt_addr = virt_addr;
+    }
+
+    if ((virt_addr + length) >
+        (map->virt_addr + map->length)) {
+        map->length = virt_addr + length - map->virt_addr;
+    }
+}
+
+void memory_mapping_list_add_merge_sorted(MemoryMappingList *list,
+                                          target_phys_addr_t phys_addr,
+                                          target_phys_addr_t virt_addr,
+                                          ram_addr_t length)
+{
+    MemoryMapping *memory_mapping, *last_mapping;
+
+    if (QTAILQ_EMPTY(&list->head)) {
+        create_new_memory_mapping(list, phys_addr, virt_addr, length);
+        return;
+    }
+
+    last_mapping = list->last_mapping;
+    if (last_mapping) {
+        if (mapping_contiguous(last_mapping, phys_addr, virt_addr)) {
+            last_mapping->length += length;
+            return;
+        }
+    }
+
+    QTAILQ_FOREACH(memory_mapping, &list->head, next) {
+        if (mapping_contiguous(memory_mapping, phys_addr, virt_addr)) {
+            memory_mapping->length += length;
+            list->last_mapping = memory_mapping;
+            return;
+        }
+
+        if (phys_addr + length < memory_mapping->phys_addr) {
+            /* create a new region before memory_mapping */
+            break;
+        }
+
+        if (mapping_have_same_region(memory_mapping, phys_addr, length)) {
+            if (mapping_conflict(memory_mapping, phys_addr, virt_addr)) {
+                continue;
+            }
+
+            /* merge this region into memory_mapping */
+            mapping_merge(memory_mapping, virt_addr, length);
+            list->last_mapping = memory_mapping;
+            return;
+        }
+    }
+
+    /* this region can not be merged into any existed memory mapping. */
+    create_new_memory_mapping(list, phys_addr, virt_addr, length);
+}
+
+void memory_mapping_list_free(MemoryMappingList *list)
+{
+    MemoryMapping *p, *q;
+
+    QTAILQ_FOREACH_SAFE(p, &list->head, next, q) {
+        QTAILQ_REMOVE(&list->head, p, next);
+        g_free(p);
+    }
+
+    list->num = 0;
+    list->last_mapping = NULL;
+}
+
+void memory_mapping_list_init(MemoryMappingList *list)
+{
+    list->num = 0;
+    list->last_mapping = NULL;
+    QTAILQ_INIT(&list->head);
+}