x86: reserve end-of-conventional-memory to 1MB on 32-bit

[sfrench/cifs-2.6.git] / arch / x86 / kernel / e820_32.c

diff --git a/arch/x86/kernel/e820_32.c b/arch/x86/kernel/e820_32.c
index 4e16ef4a2659f38f18d613289527f415d9ad92f1..0240cd778365d12a05e3096e4b7492b510573e5a 100644 (file)
--- a/arch/x86/kernel/e820_32.c
+++ b/arch/x86/kernel/e820_32.c
@@ -450,38 +450,25 @@ int __init sanitize_e820_map(struct e820entry * biosmap, char * pnr_map)
  * thinkpad 560x, for example, does not cooperate with the memory
  * detection code.)
  */
-int __init copy_e820_map(struct e820entry * biosmap, int nr_map)
+int __init copy_e820_map(struct e820entry *biosmap, int nr_map)
 {
        /* Only one memory region (or negative)? Ignore it */
        if (nr_map < 2)
                return -1;
 
        do {
-               unsigned long long start = biosmap->addr;
-               unsigned long long size = biosmap->size;
-               unsigned long long end = start + size;
-               unsigned long type = biosmap->type;
+               u64 start = biosmap->addr;
+               u64 size = biosmap->size;
+               u64 end = start + size;
+               u32 type = biosmap->type;
 
                /* Overflow in 64 bits? Ignore the memory map. */
                if (start > end)
                        return -1;
 
-               /*
-                * Some BIOSes claim RAM in the 640k - 1M region.
-                * Not right. Fix it up.
-                */
-               if (type == E820_RAM) {
-                       if (start < 0x100000ULL && end > 0xA0000ULL) {
-                               if (start < 0xA0000ULL)
-                                       add_memory_region(start, 0xA0000ULL-start, type);
-                               if (end <= 0x100000ULL)
-                                       continue;
-                               start = 0x100000ULL;
-                               size = end - start;
-                       }
-               }
                add_memory_region(start, size, type);
-       } while (biosmap++,--nr_map);
+       } while (biosmap++, --nr_map);
+
        return 0;
 }
 
@@ -749,6 +736,32 @@ static int __init parse_memmap(char *arg)
        return 0;
 }
 early_param("memmap", parse_memmap);
+void __init update_memory_range(u64 start, u64 size, unsigned old_type,
+                               unsigned new_type)
+{
+       int i;
+
+       BUG_ON(old_type == new_type);
+
+       for (i = 0; i < e820.nr_map; i++) {
+               struct e820entry *ei = &e820.map[i];
+               u64 final_start, final_end;
+               if (ei->type != old_type)
+                       continue;
+               /* totally covered? */
+               if (ei->addr >= start && ei->size <= size) {
+                       ei->type = new_type;
+                       continue;
+               }
+               /* partially covered */
+               final_start = max(start, ei->addr);
+               final_end = min(start + size, ei->addr + ei->size);
+               if (final_start >= final_end)
+                       continue;
+               add_memory_region(final_start, final_end - final_start,
+                                        new_type);
+       }
+}
 void __init update_e820(void)
 {
        u8 nr_map;