diff options
Diffstat (limited to 'arch/i386')
| -rw-r--r-- | arch/i386/kernel/setup.c | 30 |
1 files changed, 30 insertions, 0 deletions
diff --git a/arch/i386/kernel/setup.c b/arch/i386/kernel/setup.c index eacc3f0a2ea..8e70894a9f8 100644 --- a/arch/i386/kernel/setup.c +++ b/arch/i386/kernel/setup.c @@ -963,6 +963,36 @@ efi_memory_present_wrapper(unsigned long start, unsigned long end, void *arg) return 0; } + /* + * This function checks if the entire range <start,end> is mapped with type. + * + * Note: this function only works correct if the e820 table is sorted and + * not-overlapping, which is the case + */ +int __init +e820_all_mapped(unsigned long start, unsigned long end, unsigned type) +{ + int i; + for (i = 0; i < e820.nr_map; i++) { + struct e820entry *ei = &e820.map[i]; + if (type && ei->type != type) + continue; + /* is the region (part) in overlap with the current region ?*/ + if (ei->addr >= end || ei->addr + ei->size <= start) + continue; + /* if the region is at the beginning of <start,end> we move + * start to the end of the region since it's ok until there + */ + if (ei->addr <= start) + start = ei->addr + ei->size; + /* if start is now at or beyond end, we're done, full + * coverage */ + if (start >= end) + return 1; /* we're done */ + } + return 0; +} + /* * Find the highest page frame number we have available */ |