android_kernel_motorola_sm6225/arch/x86/mm/memblock.c
Maarten Lankhorst 7d68dc3f10 x86, efi: Do not reserve boot services regions within reserved areas
Commit 916f676f8d started reserving boot service code since some systems
require you to keep that code around until SetVirtualAddressMap is called.

However, in some cases those areas will overlap with reserved regions.
The proper medium-term fix is to fix the bootloader to prevent the
conflicts from occurring by moving the kernel to a better position,
but the kernel should check for this possibility, and only reserve regions
which can be reserved.

Signed-off-by: Maarten Lankhorst <m.b.lankhorst@gmail.com>
Link: http://lkml.kernel.org/r/4DF7A005.1050407@gmail.com
Acked-by: Matthew Garrett <mjg@redhat.com>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2011-06-18 22:48:49 +02:00

348 lines
8.4 KiB
C

#include <linux/kernel.h>
#include <linux/types.h>
#include <linux/init.h>
#include <linux/bitops.h>
#include <linux/memblock.h>
#include <linux/bootmem.h>
#include <linux/mm.h>
#include <linux/range.h>
/* Check for already reserved areas */
bool __init memblock_x86_check_reserved_size(u64 *addrp, u64 *sizep, u64 align)
{
struct memblock_region *r;
u64 addr = *addrp, last;
u64 size = *sizep;
bool changed = false;
again:
last = addr + size;
for_each_memblock(reserved, r) {
if (last > r->base && addr < r->base) {
size = r->base - addr;
changed = true;
goto again;
}
if (last > (r->base + r->size) && addr < (r->base + r->size)) {
addr = round_up(r->base + r->size, align);
size = last - addr;
changed = true;
goto again;
}
if (last <= (r->base + r->size) && addr >= r->base) {
*sizep = 0;
return false;
}
}
if (changed) {
*addrp = addr;
*sizep = size;
}
return changed;
}
/*
* Find next free range after start, and size is returned in *sizep
*/
u64 __init memblock_x86_find_in_range_size(u64 start, u64 *sizep, u64 align)
{
struct memblock_region *r;
for_each_memblock(memory, r) {
u64 ei_start = r->base;
u64 ei_last = ei_start + r->size;
u64 addr;
addr = round_up(ei_start, align);
if (addr < start)
addr = round_up(start, align);
if (addr >= ei_last)
continue;
*sizep = ei_last - addr;
while (memblock_x86_check_reserved_size(&addr, sizep, align))
;
if (*sizep)
return addr;
}
return MEMBLOCK_ERROR;
}
static __init struct range *find_range_array(int count)
{
u64 end, size, mem;
struct range *range;
size = sizeof(struct range) * count;
end = memblock.current_limit;
mem = memblock_find_in_range(0, end, size, sizeof(struct range));
if (mem == MEMBLOCK_ERROR)
panic("can not find more space for range array");
/*
* This range is tempoaray, so don't reserve it, it will not be
* overlapped because We will not alloccate new buffer before
* We discard this one
*/
range = __va(mem);
memset(range, 0, size);
return range;
}
static void __init memblock_x86_subtract_reserved(struct range *range, int az)
{
u64 final_start, final_end;
struct memblock_region *r;
/* Take out region array itself at first*/
memblock_free_reserved_regions();
memblock_dbg("Subtract (%ld early reservations)\n", memblock.reserved.cnt);
for_each_memblock(reserved, r) {
memblock_dbg(" [%010llx-%010llx]\n", (u64)r->base, (u64)r->base + r->size - 1);
final_start = PFN_DOWN(r->base);
final_end = PFN_UP(r->base + r->size);
if (final_start >= final_end)
continue;
subtract_range(range, az, final_start, final_end);
}
/* Put region array back ? */
memblock_reserve_reserved_regions();
}
struct count_data {
int nr;
};
static int __init count_work_fn(unsigned long start_pfn,
unsigned long end_pfn, void *datax)
{
struct count_data *data = datax;
data->nr++;
return 0;
}
static int __init count_early_node_map(int nodeid)
{
struct count_data data;
data.nr = 0;
work_with_active_regions(nodeid, count_work_fn, &data);
return data.nr;
}
int __init __get_free_all_memory_range(struct range **rangep, int nodeid,
unsigned long start_pfn, unsigned long end_pfn)
{
int count;
struct range *range;
int nr_range;
count = (memblock.reserved.cnt + count_early_node_map(nodeid)) * 2;
range = find_range_array(count);
nr_range = 0;
/*
* Use early_node_map[] and memblock.reserved.region to get range array
* at first
*/
nr_range = add_from_early_node_map(range, count, nr_range, nodeid);
subtract_range(range, count, 0, start_pfn);
subtract_range(range, count, end_pfn, -1ULL);
memblock_x86_subtract_reserved(range, count);
nr_range = clean_sort_range(range, count);
*rangep = range;
return nr_range;
}
int __init get_free_all_memory_range(struct range **rangep, int nodeid)
{
unsigned long end_pfn = -1UL;
#ifdef CONFIG_X86_32
end_pfn = max_low_pfn;
#endif
return __get_free_all_memory_range(rangep, nodeid, 0, end_pfn);
}
static u64 __init __memblock_x86_memory_in_range(u64 addr, u64 limit, bool get_free)
{
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);
/* Subtract memblock.reserved.region in range ? */
if (!get_free)
goto sort_and_count_them;
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);
}
sort_and_count_them:
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;
}
u64 __init memblock_x86_free_memory_in_range(u64 addr, u64 limit)
{
return __memblock_x86_memory_in_range(addr, limit, true);
}
u64 __init memblock_x86_memory_in_range(u64 addr, u64 limit)
{
return __memblock_x86_memory_in_range(addr, limit, false);
}
void __init memblock_x86_reserve_range(u64 start, u64 end, char *name)
{
if (start == end)
return;
if (WARN_ONCE(start > end, "memblock_x86_reserve_range: wrong range [%#llx, %#llx)\n", start, end))
return;
memblock_dbg(" memblock_x86_reserve_range: [%#010llx-%#010llx] %16s\n", start, end - 1, name);
memblock_reserve(start, end - start);
}
void __init memblock_x86_free_range(u64 start, u64 end)
{
if (start == end)
return;
if (WARN_ONCE(start > end, "memblock_x86_free_range: wrong range [%#llx, %#llx)\n", start, end))
return;
memblock_dbg(" memblock_x86_free_range: [%#010llx-%#010llx]\n", start, end - 1);
memblock_free(start, end - start);
}
/*
* Need to call this function after memblock_x86_register_active_regions,
* so early_node_map[] is filled already.
*/
u64 __init memblock_x86_find_in_range_node(int nid, u64 start, u64 end, u64 size, u64 align)
{
u64 addr;
addr = find_memory_core_early(nid, size, align, start, end);
if (addr != MEMBLOCK_ERROR)
return addr;
/* Fallback, should already have start end within node range */
return memblock_find_in_range(start, end, size, align);
}
/*
* Finds an active region in the address range from start_pfn to last_pfn and
* returns its range in ei_startpfn and ei_endpfn for the memblock entry.
*/
static int __init memblock_x86_find_active_region(const struct memblock_region *ei,
unsigned long start_pfn,
unsigned long last_pfn,
unsigned long *ei_startpfn,
unsigned long *ei_endpfn)
{
u64 align = PAGE_SIZE;
*ei_startpfn = round_up(ei->base, align) >> PAGE_SHIFT;
*ei_endpfn = round_down(ei->base + ei->size, align) >> PAGE_SHIFT;
/* Skip map entries smaller than a page */
if (*ei_startpfn >= *ei_endpfn)
return 0;
/* Skip if map is outside the node */
if (*ei_endpfn <= start_pfn || *ei_startpfn >= last_pfn)
return 0;
/* Check for overlaps */
if (*ei_startpfn < start_pfn)
*ei_startpfn = start_pfn;
if (*ei_endpfn > last_pfn)
*ei_endpfn = last_pfn;
return 1;
}
/* Walk the memblock.memory map and register active regions within a node */
void __init memblock_x86_register_active_regions(int nid, unsigned long start_pfn,
unsigned long last_pfn)
{
unsigned long ei_startpfn;
unsigned long ei_endpfn;
struct memblock_region *r;
for_each_memblock(memory, r)
if (memblock_x86_find_active_region(r, start_pfn, last_pfn,
&ei_startpfn, &ei_endpfn))
add_active_range(nid, ei_startpfn, ei_endpfn);
}
/*
* Find the hole size (in bytes) in the memory range.
* @start: starting address of the memory range to scan
* @end: ending address of the memory range to scan
*/
u64 __init memblock_x86_hole_size(u64 start, u64 end)
{
unsigned long start_pfn = start >> PAGE_SHIFT;
unsigned long last_pfn = end >> PAGE_SHIFT;
unsigned long ei_startpfn, ei_endpfn, ram = 0;
struct memblock_region *r;
for_each_memblock(memory, r)
if (memblock_x86_find_active_region(r, start_pfn, last_pfn,
&ei_startpfn, &ei_endpfn))
ram += ei_endpfn - ei_startpfn;
return end - start - ((u64)ram << PAGE_SHIFT);
}