x86, memblock: Add memblock_x86_free_memory_in_range()

It will return free memory size in specified range.

We can not use memory_size - reserved_size here, because some reserved area
may not be in the scope of memblock.memory.region.

Use memblock.memory.region subtracting memblock.reserved.region to get free range array.
then count size of all free ranges.

-v2: Ben insist on using _in_range

Signed-off-by: Yinghai Lu <yinghai@kernel.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
This commit is contained in:
Yinghai Lu 2010-08-25 13:39:16 -07:00 committed by H. Peter Anvin
parent 6bcc8176d0
commit b52c17ce85
2 changed files with 49 additions and 0 deletions

View File

@ -15,5 +15,6 @@ void memblock_x86_register_active_regions(int nid, unsigned long start_pfn,
unsigned long last_pfn);
u64 memblock_x86_hole_size(u64 start, u64 end);
u64 memblock_x86_find_in_range_node(int nid, u64 start, u64 end, u64 size, u64 align);
u64 memblock_x86_free_memory_in_range(u64 addr, u64 limit);
#endif

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@ -211,6 +211,54 @@ void __init memblock_x86_to_bootmem(u64 start, u64 end)
}
#endif
u64 __init memblock_x86_free_memory_in_range(u64 addr, u64 limit)
{
int i, count;
struct range *range;
int nr_range;
u64 final_start, final_end;
u64 free_size;
struct memblock_region *r;
count = (memblock.reserved.cnt + memblock.memory.cnt) * 2;
range = find_range_array(count);
nr_range = 0;
addr = PFN_UP(addr);
limit = PFN_DOWN(limit);
for_each_memblock(memory, r) {
final_start = PFN_UP(r->base);
final_end = PFN_DOWN(r->base + r->size);
if (final_start >= final_end)
continue;
if (final_start >= limit || final_end <= addr)
continue;
nr_range = add_range(range, count, nr_range, final_start, final_end);
}
subtract_range(range, count, 0, addr);
subtract_range(range, count, limit, -1ULL);
for_each_memblock(reserved, r) {
final_start = PFN_DOWN(r->base);
final_end = PFN_UP(r->base + r->size);
if (final_start >= final_end)
continue;
if (final_start >= limit || final_end <= addr)
continue;
subtract_range(range, count, final_start, final_end);
}
nr_range = clean_sort_range(range, count);
free_size = 0;
for (i = 0; i < nr_range; i++)
free_size += range[i].end - range[i].start;
return free_size << PAGE_SHIFT;
}
void __init memblock_x86_reserve_range(u64 start, u64 end, char *name)
{
if (start == end)