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Commit 72d4b0b4 authored by Benjamin Herrenschmidt's avatar Benjamin Herrenschmidt
Browse files

memblock: Implement memblock_is_memory and memblock_is_region_memory 



To make it fast, we steal ARM's binary search for memblock_is_memory()
and we use that to also the replace existing implementation of
memblock_is_reserved().

Signed-off-by: default avatarBenjamin Herrenschmidt <benh@kernel.crashing.org>
parent 411a25a8

include/linux/memblock.h

+2 −0
Original line number Diff line number Diff line
@@ -56,6 +56,8 @@ extern u64 __init __memblock_alloc_base(u64 size, 
extern u64 __init memblock_phys_mem_size(void);

extern u64 memblock_end_of_DRAM(void);

extern void __init memblock_enforce_memory_limit(u64 memory_limit);

extern int memblock_is_memory(u64 addr);

extern int memblock_is_region_memory(u64 base, u64 size);

extern int __init memblock_is_reserved(u64 addr);

extern int memblock_is_region_reserved(u64 base, u64 size);

extern int memblock_find(struct memblock_region *res);

mm/memblock.c

+34 −8
Original line number Diff line number Diff line
@@ -487,17 +487,43 @@ void __init memblock_enforce_memory_limit(u64 memory_limit) 
	}

}



static int memblock_search(struct memblock_type *type, u64 addr)

{

	unsigned int left = 0, right = type->cnt;



	do {

		unsigned int mid = (right + left) / 2;



		if (addr < type->regions[mid].base)

			right = mid;

		else if (addr >= (type->regions[mid].base +

				  type->regions[mid].size))

			left = mid + 1;

		else

			return mid;

	} while (left < right);

	return -1;

}



int __init memblock_is_reserved(u64 addr)

{

	int i;

	return memblock_search(&memblock.reserved, addr) != -1;

}



	for (i = 0; i < memblock.reserved.cnt; i++) {

		u64 upper = memblock.reserved.regions[i].base +

			memblock.reserved.regions[i].size - 1;

		if ((addr >= memblock.reserved.regions[i].base) && (addr <= upper))

			return 1;

int memblock_is_memory(u64 addr)

{

	return memblock_search(&memblock.memory, addr) != -1;

}



int memblock_is_region_memory(u64 base, u64 size)

{

	int idx = memblock_search(&memblock.reserved, base);



	if (idx == -1)

		return 0;

	return memblock.reserved.regions[idx].base <= base &&

		(memblock.reserved.regions[idx].base +

		 memblock.reserved.regions[idx].size) >= (base + size);

}



int memblock_is_region_reserved(u64 base, u64 size)