[PATCH 6/7] bootmem: use pfn/page conversion macros

From: Franck Bui-Huu
Date: Tue Jul 04 2006 - 11:40:12 EST


It also creates get_mapsize() helper in order to make the code
more readable when it calculates the boot bitmap size.

Signed-off-by: Franck Bui-Huu <vagabon.xyz@xxxxxxxxx>

---
mm/bootmem.c | 82 ++++++++++++++++++++++++++++++++--------------------------
1 files changed, 45 insertions(+), 37 deletions(-)

diff --git a/mm/bootmem.c b/mm/bootmem.c
index 86213da..3368a14 100644
--- a/mm/bootmem.c
+++ b/mm/bootmem.c
@@ -9,6 +9,7 @@
* system memory and memory holes as well.
*/
#include <linux/init.h>
+#include <linux/pfn.h>
#include <linux/bootmem.h>
#include <linux/module.h>

@@ -70,6 +71,18 @@ static void __init link_bootmem(bootmem_
return;
}

+/*
+ * Given an initialised bdata, it returns the size of the boot bitmap
+ */
+static unsigned long __init get_mapsize(bootmem_data_t *bdata)
+{
+ unsigned long mapsize;
+ unsigned long start = PFN_DOWN(bdata->node_boot_start);
+ unsigned long end = bdata->node_low_pfn;
+
+ mapsize = ((end - start) + 7) / 8;
+ return ALIGN(mapsize, sizeof(long));
+}

/*
* Called once to set up the allocator itself.
@@ -78,11 +91,10 @@ static unsigned long __init init_bootmem
unsigned long mapstart, unsigned long start, unsigned long end)
{
bootmem_data_t *bdata = pgdat->bdata;
- unsigned long mapsize = ((end - start)+7)/8;
+ unsigned long mapsize;

- mapsize = ALIGN(mapsize, sizeof(long));
- bdata->node_bootmem_map = phys_to_virt(mapstart << PAGE_SHIFT);
- bdata->node_boot_start = (start << PAGE_SHIFT);
+ bdata->node_bootmem_map = phys_to_virt(PFN_PHYS(mapstart));
+ bdata->node_boot_start = PFN_PHYS(start);
bdata->node_low_pfn = end;
link_bootmem(bdata);

@@ -90,6 +102,7 @@ static unsigned long __init init_bootmem
* Initially all pages are reserved - setup_arch() has to
* register free RAM areas explicitly.
*/
+ mapsize = get_mapsize(bdata);
memset(bdata->node_bootmem_map, 0xff, mapsize);

return mapsize;
@@ -103,20 +116,19 @@ static unsigned long __init init_bootmem
static void __init reserve_bootmem_core(bootmem_data_t *bdata, unsigned long addr,
unsigned long size)
{
+ unsigned long sidx, eidx;
unsigned long i;
+
/*
* round up, partially reserved pages are considered
* fully reserved.
*/
- unsigned long sidx = (addr - bdata->node_boot_start)/PAGE_SIZE;
- unsigned long eidx = (addr + size - bdata->node_boot_start +
- PAGE_SIZE-1)/PAGE_SIZE;
- unsigned long end = (addr + size + PAGE_SIZE-1)/PAGE_SIZE;
-
BUG_ON(!size);
- BUG_ON(sidx >= eidx);
- BUG_ON((addr >> PAGE_SHIFT) >= bdata->node_low_pfn);
- BUG_ON(end > bdata->node_low_pfn);
+ BUG_ON(PFN_DOWN(addr) >= bdata->node_low_pfn);
+ BUG_ON(PFN_UP(addr + size) > bdata->node_low_pfn);
+
+ sidx = PFN_DOWN(addr - bdata->node_boot_start);
+ eidx = PFN_UP(addr + size - bdata->node_boot_start);

for (i = sidx; i < eidx; i++)
if (test_and_set_bit(i, bdata->node_bootmem_map)) {
@@ -129,18 +141,15 @@ #endif
static void __init free_bootmem_core(bootmem_data_t *bdata, unsigned long addr,
unsigned long size)
{
+ unsigned long sidx, eidx;
unsigned long i;
- unsigned long start;
+
/*
* round down end of usable mem, partially free pages are
* considered reserved.
*/
- unsigned long sidx;
- unsigned long eidx = (addr + size - bdata->node_boot_start)/PAGE_SIZE;
- unsigned long end = (addr + size)/PAGE_SIZE;
-
BUG_ON(!size);
- BUG_ON(end > bdata->node_low_pfn);
+ BUG_ON(PFN_DOWN(addr + size) > bdata->node_low_pfn);

if (addr < bdata->last_success)
bdata->last_success = addr;
@@ -148,8 +157,8 @@ static void __init free_bootmem_core(boo
/*
* Round up the beginning of the address.
*/
- start = (addr + PAGE_SIZE-1) / PAGE_SIZE;
- sidx = start - (bdata->node_boot_start/PAGE_SIZE);
+ sidx = PFN_UP(addr) - PFN_DOWN(bdata->node_boot_start);
+ eidx = PFN_DOWN(addr + size - bdata->node_boot_start);

for (i = sidx; i < eidx; i++) {
if (unlikely(!test_and_clear_bit(i, bdata->node_bootmem_map)))
@@ -175,7 +184,7 @@ __alloc_bootmem_core(struct bootmem_data
unsigned long align, unsigned long goal, unsigned long limit)
{
unsigned long offset, remaining_size, areasize, preferred;
- unsigned long i, start = 0, incr, eidx, end_pfn = bdata->node_low_pfn;
+ unsigned long i, start = 0, incr, eidx, end_pfn;
void *ret;

if(!size) {
@@ -187,23 +196,22 @@ __alloc_bootmem_core(struct bootmem_data
if (limit && bdata->node_boot_start >= limit)
return NULL;

- limit >>=PAGE_SHIFT;
+ end_pfn = bdata->node_low_pfn;
+ limit = PFN_DOWN(limit);
if (limit && end_pfn > limit)
end_pfn = limit;

- eidx = end_pfn - (bdata->node_boot_start >> PAGE_SHIFT);
+ eidx = end_pfn - PFN_DOWN(bdata->node_boot_start);
offset = 0;
- if (align &&
- (bdata->node_boot_start & (align - 1UL)) != 0)
- offset = (align - (bdata->node_boot_start & (align - 1UL)));
- offset >>= PAGE_SHIFT;
+ if (align && (bdata->node_boot_start & (align - 1UL)) != 0)
+ offset = align - (bdata->node_boot_start & (align - 1UL));
+ offset = PFN_DOWN(offset);

/*
* We try to allocate bootmem pages above 'goal'
* first, then we try to allocate lower pages.
*/
- if (goal && (goal >= bdata->node_boot_start) &&
- ((goal >> PAGE_SHIFT) < end_pfn)) {
+ if (goal && goal >= bdata->node_boot_start && PFN_DOWN(goal) < end_pfn) {
preferred = goal - bdata->node_boot_start;

if (bdata->last_success >= preferred)
@@ -212,9 +220,8 @@ __alloc_bootmem_core(struct bootmem_data
} else
preferred = 0;

- preferred = ALIGN(preferred, align) >> PAGE_SHIFT;
- preferred += offset;
- areasize = (size+PAGE_SIZE-1)/PAGE_SIZE;
+ preferred = PFN_DOWN(ALIGN(preferred, align)) + offset;
+ areasize = (size + PAGE_SIZE-1) / PAGE_SIZE;
incr = align >> PAGE_SHIFT ? : 1;

restart_scan:
@@ -245,7 +252,7 @@ restart_scan:
return NULL;

found:
- bdata->last_success = start << PAGE_SHIFT;
+ bdata->last_success = PFN_PHYS(start);
BUG_ON(start >= eidx);

/*
@@ -303,8 +310,8 @@ static unsigned long __init free_all_boo

count = 0;
/* first extant page of the node */
- pfn = bdata->node_boot_start >> PAGE_SHIFT;
- idx = bdata->node_low_pfn - (bdata->node_boot_start >> PAGE_SHIFT);
+ pfn = PFN_DOWN(bdata->node_boot_start);
+ idx = bdata->node_low_pfn - pfn;
map = bdata->node_bootmem_map;
/* Check physaddr is O(LOG2(BITS_PER_LONG)) page aligned */
if (bdata->node_boot_start == 0 ||
@@ -345,9 +352,10 @@ static unsigned long __init free_all_boo
*/
page = virt_to_page(bdata->node_bootmem_map);
count = 0;
- for (i = 0; i < ((bdata->node_low_pfn-(bdata->node_boot_start >> PAGE_SHIFT))/8 + PAGE_SIZE-1)/PAGE_SIZE; i++,page++) {
- count++;
+ idx = (get_mapsize(bdata) + PAGE_SIZE-1) >> PAGE_SHIFT;
+ for (i = 0; i < idx; i++, page++) {
__free_pages_bootmem(page, 0);
+ count++;
}
total += count;
bdata->node_bootmem_map = NULL;
--
1.4.1.g35c6

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