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memblock: Implement memblock_is_memory and memblock_is_region_memory

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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: Benjamin Herrenschmidt <benh@kernel.crashing.org>
This commit is contained in:
Benjamin Herrenschmidt 2010-08-04 14:38:47 +10:00
parent 411a25a80d
commit 72d4b0b4e0
2 changed files with 36 additions and 8 deletions
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2
include/linux/memblock.h
View file

@ -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);

42
mm/memblock.c
View file

@ -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;
}
return 0;
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)