x86_64: extract helper function from e820_register_active_regions

The logic in e820_find_active_regions() for determining the true active
regions for an e820 entry given a range of PFN's is needed for
e820_hole_size() as well.

e820_hole_size() is called from the NUMA emulation code to determine the
reserved area within an address range on a per-node basis.  Its logic should
duplicate that of finding active regions in an e820 entry because these are
the only true ranges we may register anyway.

[akpm@linux-foundation.org: cleanup]
Cc: Mel Gorman <mel@csn.ul.ie>
Signed-off-by: David Rientjes <rientjes@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Andi Kleen <ak@suse.de>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This commit is contained in:
David Rientjes 2007-07-21 17:10:31 +02:00 committed by Linus Torvalds
parent 34feb2c83b
commit 3af044e0f8

View File

@ -289,47 +289,61 @@ void __init e820_mark_nosave_regions(void)
}
}
/*
* Finds an active region in the address range from start_pfn to end_pfn and
* returns its range in ei_startpfn and ei_endpfn for the e820 entry.
*/
static int __init e820_find_active_region(const struct e820entry *ei,
unsigned long start_pfn,
unsigned long end_pfn,
unsigned long *ei_startpfn,
unsigned long *ei_endpfn)
{
*ei_startpfn = round_up(ei->addr, PAGE_SIZE) >> PAGE_SHIFT;
*ei_endpfn = round_down(ei->addr + ei->size, PAGE_SIZE) >> PAGE_SHIFT;
/* Skip map entries smaller than a page */
if (*ei_startpfn >= *ei_endpfn)
return 0;
/* Check if end_pfn_map should be updated */
if (ei->type != E820_RAM && *ei_endpfn > end_pfn_map)
end_pfn_map = *ei_endpfn;
/* Skip if map is outside the node */
if (ei->type != E820_RAM || *ei_endpfn <= start_pfn ||
*ei_startpfn >= end_pfn)
return 0;
/* Check for overlaps */
if (*ei_startpfn < start_pfn)
*ei_startpfn = start_pfn;
if (*ei_endpfn > end_pfn)
*ei_endpfn = end_pfn;
/* Obey end_user_pfn to save on memmap */
if (*ei_startpfn >= end_user_pfn)
return 0;
if (*ei_endpfn > end_user_pfn)
*ei_endpfn = end_user_pfn;
return 1;
}
/* Walk the e820 map and register active regions within a node */
void __init
e820_register_active_regions(int nid, unsigned long start_pfn,
unsigned long end_pfn)
{
unsigned long ei_startpfn;
unsigned long ei_endpfn;
int i;
unsigned long ei_startpfn, ei_endpfn;
for (i = 0; i < e820.nr_map; i++) {
struct e820entry *ei = &e820.map[i];
ei_startpfn = round_up(ei->addr, PAGE_SIZE) >> PAGE_SHIFT;
ei_endpfn = round_down(ei->addr + ei->size, PAGE_SIZE)
>> PAGE_SHIFT;
/* Skip map entries smaller than a page */
if (ei_startpfn >= ei_endpfn)
continue;
/* Check if end_pfn_map should be updated */
if (ei->type != E820_RAM && ei_endpfn > end_pfn_map)
end_pfn_map = ei_endpfn;
/* Skip if map is outside the node */
if (ei->type != E820_RAM ||
ei_endpfn <= start_pfn ||
ei_startpfn >= end_pfn)
continue;
/* Check for overlaps */
if (ei_startpfn < start_pfn)
ei_startpfn = start_pfn;
if (ei_endpfn > end_pfn)
ei_endpfn = end_pfn;
/* Obey end_user_pfn to save on memmap */
if (ei_startpfn >= end_user_pfn)
continue;
if (ei_endpfn > end_user_pfn)
ei_endpfn = end_user_pfn;
add_active_range(nid, ei_startpfn, ei_endpfn);
}
for (i = 0; i < e820.nr_map; i++)
if (e820_find_active_region(&e820.map[i],
start_pfn, end_pfn,
&ei_startpfn, &ei_endpfn))
add_active_range(nid, ei_startpfn, ei_endpfn);
}
/*