[PATCH] mm: split highorder pages
Have an explicit mm call to split higher order pages into individual pages.
Should help to avoid bugs and be more explicit about the code's intention.
Signed-off-by: Nick Piggin <npiggin@suse.de>
Cc: Russell King <rmk@arm.linux.org.uk>
Cc: David Howells <dhowells@redhat.com>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mundt <lethal@linux-sh.org>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Chris Zankel <chris@zankel.net>
Signed-off-by: Yoichi Yuasa <yoichi_yuasa@tripeaks.co.jp>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
diff --git a/arch/arm/mm/consistent.c b/arch/arm/mm/consistent.c
index c2ee18d..8a1bfcd 100644
--- a/arch/arm/mm/consistent.c
+++ b/arch/arm/mm/consistent.c
@@ -223,6 +223,8 @@
pte = consistent_pte[idx] + off;
c->vm_pages = page;
+ split_page(page, order);
+
/*
* Set the "dma handle"
*/
@@ -231,7 +233,6 @@
do {
BUG_ON(!pte_none(*pte));
- set_page_count(page, 1);
/*
* x86 does not mark the pages reserved...
*/
@@ -250,7 +251,6 @@
* Free the otherwise unused pages.
*/
while (page < end) {
- set_page_count(page, 1);
__free_page(page);
page++;
}
diff --git a/arch/frv/mm/dma-alloc.c b/arch/frv/mm/dma-alloc.c
index 342823a..636b2f8 100644
--- a/arch/frv/mm/dma-alloc.c
+++ b/arch/frv/mm/dma-alloc.c
@@ -115,9 +115,7 @@
*/
if (order > 0) {
struct page *rpage = virt_to_page(page);
-
- for (i = 1; i < (1 << order); i++)
- set_page_count(rpage + i, 1);
+ split_page(rpage, order);
}
err = 0;
diff --git a/arch/mips/mm/init.c b/arch/mips/mm/init.c
index 0ff9a34..a140da9 100644
--- a/arch/mips/mm/init.c
+++ b/arch/mips/mm/init.c
@@ -54,7 +54,8 @@
*/
unsigned long setup_zero_pages(void)
{
- unsigned long order, size;
+ unsigned int order;
+ unsigned long size;
struct page *page;
if (cpu_has_vce)
@@ -67,9 +68,9 @@
panic("Oh boy, that early out of memory?");
page = virt_to_page(empty_zero_page);
+ split_page(page, order);
while (page < virt_to_page(empty_zero_page + (PAGE_SIZE << order))) {
SetPageReserved(page);
- set_page_count(page, 1);
page++;
}
diff --git a/arch/ppc/kernel/dma-mapping.c b/arch/ppc/kernel/dma-mapping.c
index 685fd0d..61465ec 100644
--- a/arch/ppc/kernel/dma-mapping.c
+++ b/arch/ppc/kernel/dma-mapping.c
@@ -223,6 +223,8 @@
pte_t *pte = consistent_pte + CONSISTENT_OFFSET(vaddr);
struct page *end = page + (1 << order);
+ split_page(page, order);
+
/*
* Set the "dma handle"
*/
@@ -231,7 +233,6 @@
do {
BUG_ON(!pte_none(*pte));
- set_page_count(page, 1);
SetPageReserved(page);
set_pte_at(&init_mm, vaddr,
pte, mk_pte(page, pgprot_noncached(PAGE_KERNEL)));
@@ -244,7 +245,6 @@
* Free the otherwise unused pages.
*/
while (page < end) {
- set_page_count(page, 1);
__free_page(page);
page++;
}
diff --git a/arch/sh/mm/consistent.c b/arch/sh/mm/consistent.c
index df3a9e4..ee73e30 100644
--- a/arch/sh/mm/consistent.c
+++ b/arch/sh/mm/consistent.c
@@ -23,6 +23,7 @@
page = alloc_pages(gfp, order);
if (!page)
return NULL;
+ split_page(page, order);
ret = page_address(page);
*handle = virt_to_phys(ret);
@@ -37,8 +38,6 @@
end = page + (1 << order);
while (++page < end) {
- set_page_count(page, 1);
-
/* Free any unused pages */
if (page >= free) {
__free_page(page);
diff --git a/arch/xtensa/mm/pgtable.c b/arch/xtensa/mm/pgtable.c
index cbc56ae..7d28914 100644
--- a/arch/xtensa/mm/pgtable.c
+++ b/arch/xtensa/mm/pgtable.c
@@ -21,13 +21,9 @@
p = (pte_t*) __get_free_pages(GFP_KERNEL|__GFP_REPEAT, COLOR_ORDER);
if (likely(p)) {
- struct page *page;
+ split_page(virt_to_page(p), COLOR_ORDER);
for (i = 0; i < COLOR_SIZE; i++) {
- page = virt_to_page(p);
-
- set_page_count(page, 1);
-
if (ADDR_COLOR(p) == color)
pte = p;
else
@@ -55,9 +51,9 @@
p = alloc_pages(GFP_KERNEL | __GFP_REPEAT, PTE_ORDER);
if (likely(p)) {
- for (i = 0; i < PAGE_ORDER; i++) {
- set_page_count(p, 1);
+ split_page(p, COLOR_ORDER);
+ for (i = 0; i < PAGE_ORDER; i++) {
if (PADDR_COLOR(page_address(p)) == color)
page = p;
else