| // Support for building memory maps suitable for int 15 e820 calls. |
| // |
| // Copyright (C) 2008,2009 Kevin O'Connor <kevin@koconnor.net> |
| // |
| // This file may be distributed under the terms of the GNU LGPLv3 license. |
| |
| #include "memmap.h" // struct e820entry |
| #include "config.h" // CONFIG_* |
| #include "util.h" // dprintf.h |
| |
| |
| /**************************************************************** |
| * e820 memory map |
| ****************************************************************/ |
| |
| // Remove an entry from the e820_list. |
| static void |
| remove_e820(int i) |
| { |
| e820_count--; |
| memmove(&e820_list[i], &e820_list[i+1] |
| , sizeof(e820_list[0]) * (e820_count - i)); |
| } |
| |
| // Insert an entry in the e820_list at the given position. |
| static void |
| insert_e820(int i, u64 start, u64 size, u32 type) |
| { |
| if (e820_count >= CONFIG_MAX_E820) { |
| warn_noalloc(); |
| return; |
| } |
| |
| memmove(&e820_list[i+1], &e820_list[i] |
| , sizeof(e820_list[0]) * (e820_count - i)); |
| e820_count++; |
| struct e820entry *e = &e820_list[i]; |
| e->start = start; |
| e->size = size; |
| e->type = type; |
| } |
| |
| static const char * |
| e820_type_name(u32 type) |
| { |
| switch (type) { |
| case E820_RAM: return "RAM"; |
| case E820_RESERVED: return "RESERVED"; |
| case E820_ACPI: return "ACPI"; |
| case E820_NVS: return "NVS"; |
| case E820_UNUSABLE: return "UNUSABLE"; |
| case E820_HOLE: return "HOLE"; |
| default: return "UNKNOWN"; |
| } |
| } |
| |
| // Show the current e820_list. |
| static void |
| dump_map(void) |
| { |
| dprintf(1, "e820 map has %d items:\n", e820_count); |
| int i; |
| for (i=0; i<e820_count; i++) { |
| struct e820entry *e = &e820_list[i]; |
| u64 e_end = e->start + e->size; |
| dprintf(1, " %d: %016llx - %016llx = %d %s\n", i |
| , e->start, e_end, e->type, e820_type_name(e->type)); |
| } |
| } |
| |
| // Add a new entry to the list. This scans for overlaps and keeps the |
| // list sorted. |
| void |
| add_e820(u64 start, u64 size, u32 type) |
| { |
| dprintf(8, "Add to e820 map: %08x %08x %d\n", (u32)start, (u32)size, type); |
| |
| if (! size) |
| // Huh? Nothing to do. |
| return; |
| |
| // Find position of new item (splitting existing item if needed). |
| u64 end = start + size; |
| int i; |
| for (i=0; i<e820_count; i++) { |
| struct e820entry *e = &e820_list[i]; |
| u64 e_end = e->start + e->size; |
| if (start > e_end) |
| continue; |
| // Found position - check if an existing item needs to be split. |
| if (start > e->start) { |
| if (type == e->type) { |
| // Same type - merge them. |
| size += start - e->start; |
| start = e->start; |
| } else { |
| // Split existing item. |
| e->size = start - e->start; |
| i++; |
| if (e_end > end) |
| insert_e820(i, end, e_end - end, e->type); |
| } |
| } |
| break; |
| } |
| // Remove/adjust existing items that are overlapping. |
| while (i<e820_count) { |
| struct e820entry *e = &e820_list[i]; |
| if (end < e->start) |
| // No overlap - done. |
| break; |
| u64 e_end = e->start + e->size; |
| if (end >= e_end) { |
| // Existing item completely overlapped - remove it. |
| remove_e820(i); |
| continue; |
| } |
| // Not completely overlapped - adjust its start. |
| e->start = end; |
| e->size = e_end - end; |
| if (type == e->type) { |
| // Same type - merge them. |
| size += e->size; |
| remove_e820(i); |
| } |
| break; |
| } |
| // Insert new item. |
| if (type != E820_HOLE) |
| insert_e820(i, start, size, type); |
| //dump_map(); |
| } |
| |
| // Report on final memory locations. |
| void |
| memmap_finalize(void) |
| { |
| dump_map(); |
| } |