[PATCH] reduce swsusp casting

From: Dave Hansen
Date: Wed Jul 28 2004 - 14:42:11 EST

I noticed that swsusp uses quite a few interesting casts for __pa() and
cousins. This patch moves some types around to eliminate some of those
casts in the normal code. The casts that it adds are around alloc's and
frees, which is a much more usual place to see them.

Pavel also noticed that there's a superfluous PAGE_ALIGN() right before
a >>PAGE_SHIFT in pfn_is_nosave(), so that's been removed as well.

I haven't had a chance to do anything but test it, because that would
involve me setting up a swsusp rig, which I'm more prone to screw up
than the patch itself :) I'd appreciate if anyone with a stable setup
could make sure I didn't do anything too stupid.

-- Dave
--- ./linux-2.6.8-rc1-mm1-typefix/kernel/power/swsusp.c.orig 2004-07-27 15:46:20.000000000 -0700
+++ ./linux-2.6.8-rc1-mm1-typefix/kernel/power/swsusp.c 2004-07-28 12:18:48.000000000 -0700
@@ -307,7 +307,6 @@ static int write_suspend_image(void)
swp_entry_t entry, prev = { 0 };
int nr_pgdir_pages = SUSPEND_PD_PAGES(nr_copy_pages);
union diskpage *cur, *buffer = (union diskpage *)get_zeroed_page(GFP_ATOMIC);
- unsigned long address;
struct page *page;

if (!buffer)
@@ -324,8 +323,7 @@ static int write_suspend_image(void)
if (swapfile_used[swp_type(entry)] != SWAPFILE_SUSPEND)
panic("\nPage %d: not enough swapspace on suspend device", i );

- address = (pagedir_nosave+i)->address;
- page = virt_to_page(address);
+ page = virt_to_page((pagedir_nosave+i)->address);
rw_swap_page_sync(WRITE, entry, page);
(pagedir_nosave+i)->swap_address = entry;
}
@@ -350,7 +348,7 @@ static int write_suspend_image(void)
BUG_ON (PAGE_SIZE % sizeof(struct pbe));

cur->link.next = prev;
- page = virt_to_page((unsigned long)cur);
+ page = virt_to_page(cur);
rw_swap_page_sync(WRITE, entry, page);
prev = entry;
}
@@ -370,7 +368,7 @@ static int write_suspend_image(void)

cur->link.next = prev;

- page = virt_to_page((unsigned long)cur);
+ page = virt_to_page(cur);
rw_swap_page_sync(WRITE, entry, page);
prev = entry;

@@ -471,8 +469,8 @@ static int restore_highmem(void)

static int pfn_is_nosave(unsigned long pfn)
{
- unsigned long nosave_begin_pfn = __pa(&__nosave_begin) >> PAGE_SHIFT;
- unsigned long nosave_end_pfn = PAGE_ALIGN(__pa(&__nosave_end)) >> PAGE_SHIFT;
+ unsigned long nosave_begin_pfn = virt_to_phys(&__nosave_begin) >> PAGE_SHIFT;
+ unsigned long nosave_end_pfn = virt_to_phys(&__nosave_end) >> PAGE_SHIFT;
return (pfn >= nosave_begin_pfn) && (pfn < nosave_end_pfn);
}

@@ -527,12 +525,13 @@ static int count_and_copy_data_pages(str
return nr_copy_pages;
}

-static void free_suspend_pagedir_zone(struct zone *zone, unsigned long pagedir)
+static void free_suspend_pagedir_zone(struct zone *zone, suspend_pagedir_t *pagedir)
{
- unsigned long zone_pfn, pagedir_end, pagedir_pfn, pagedir_end_pfn;
- pagedir_end = pagedir + (PAGE_SIZE << pagedir_order);
- pagedir_pfn = __pa(pagedir) >> PAGE_SHIFT;
- pagedir_end_pfn = __pa(pagedir_end) >> PAGE_SHIFT;
+ unsigned long zone_pfn, pagedir_pfn, pagedir_end, pagedir_end_pfn;
+ unsigned long pagedir_paddr = virt_to_phys(pagedir);
+ pagedir_end = pagedir_paddr + (PAGE_SIZE << pagedir_order);
+ pagedir_pfn = pagedir_paddr >> PAGE_SHIFT;
+ pagedir_end_pfn = pagedir_end >> PAGE_SHIFT;
for (zone_pfn = 0; zone_pfn < zone->spanned_pages; ++zone_pfn) {
struct page *page;
unsigned long pfn = zone_pfn + zone->zone_start_pfn;
@@ -547,14 +546,14 @@ static void free_suspend_pagedir_zone(st
}
}

-static void free_suspend_pagedir(unsigned long this_pagedir)
+static void free_suspend_pagedir(suspend_pagedir_t *this_pagedir)
{
struct zone *zone;
for_each_zone(zone) {
if (!is_highmem(zone))
free_suspend_pagedir_zone(zone, this_pagedir);
}
- free_pages(this_pagedir, pagedir_order);
+ free_pages((unsigned long)this_pagedir, pagedir_order);
}

static suspend_pagedir_t *create_suspend_pagedir(int nr_copy_pages)
@@ -575,9 +574,9 @@ static suspend_pagedir_t *create_suspend
SetPageNosave(page++);

while(nr_copy_pages--) {
- p->address = get_zeroed_page(GFP_ATOMIC | __GFP_COLD);
+ p->address = (unsigned char *)get_zeroed_page(GFP_ATOMIC | __GFP_COLD);
if (!p->address) {
- free_suspend_pagedir((unsigned long) pagedir);
+ free_suspend_pagedir(pagedir);
return NULL;
}
SetPageNosave(virt_to_page(p->address));
@@ -735,7 +734,7 @@ asmlinkage void do_magic_resume_2(void)
__flush_tlb_global(); /* Even mappings of "global" things (vmalloc) need to be fixed */

PRINTK( "Freeing prev allocated pagedir\n" );
- free_suspend_pagedir((unsigned long) pagedir_save);
+ free_suspend_pagedir(pagedir_save);

#ifdef CONFIG_HIGHMEM
printk( "Restoring highmem\n" );
@@ -874,10 +873,11 @@ int software_suspend(void)
/*
* Returns true if given address/order collides with any orig_address
*/
-static int does_collide_order(suspend_pagedir_t *pagedir, unsigned long addr,
+static int does_collide_order(suspend_pagedir_t *pagedir, void *ptr,
int order)
{
int i;
+ unsigned long addr = (unsigned long)ptr;
unsigned long addre = addr + (PAGE_SIZE<<order);

for(i=0; i < nr_copy_pages; i++)
@@ -897,15 +897,15 @@ static int check_pagedir(void)
int i;

for(i=0; i < nr_copy_pages; i++) {
- unsigned long addr;
+ void *newpage;

do {
- addr = get_zeroed_page(GFP_ATOMIC);
- if(!addr)
+ newpage = (void *)get_zeroed_page(GFP_ATOMIC);
+ if(!newpage)
return -ENOMEM;
- } while (does_collide(addr));
+ } while (does_collide(newpage));

- (pagedir_nosave+i)->address = addr;
+ (pagedir_nosave+i)->address = newpage;
}
return 0;
}
@@ -923,13 +923,13 @@ static int relocate_pagedir(void)

printk("Relocating pagedir ");

- if(!does_collide_order(old_pagedir, (unsigned long)old_pagedir, pagedir_order)) {
+ if(!does_collide_order(old_pagedir, old_pagedir, pagedir_order)) {
printk("not necessary\n");
return 0;
}

while ((m = (void *) __get_free_pages(GFP_ATOMIC, pagedir_order)) != NULL) {
- if (!does_collide_order(old_pagedir, (unsigned long)m, pagedir_order))
+ if (!does_collide_order(old_pagedir, m, pagedir_order))
break;
eaten_memory = m;
printk( "." );