From: Dave Hansen <haveblue@us.ibm.com>
People love to do comparisons with highmem_start_page. However, where
CONFIG_HIGHMEM=y and there is no actual highmem, there's no real page at
*highmem_start_page.
That's usually not a problem, but CONFIG_NONLINEAR is a bit more strict and
catches the bogus address tranlations.
There are about a gillion different ways to find out of a 'struct page' is
highmem or not. Why not just check page_flags? Just use PageHighMem()
wherever there used to be a highmem_start_page comparison. Then, kill off
highmem_start_page.
This removes more code than it adds, and gets rid of some nasty
#ifdefs in .c files.
Signed-off-by: Dave Hansen <haveblue@us.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
---
25-akpm/arch/i386/mm/discontig.c | 5 -----
25-akpm/arch/i386/mm/highmem.c | 6 +++---
25-akpm/arch/i386/mm/init.c | 1 -
25-akpm/arch/i386/mm/pageattr.c | 5 +----
25-akpm/arch/mips/mm/highmem.c | 6 +++---
25-akpm/arch/mips/mm/init.c | 1 -
25-akpm/arch/ppc/mm/init.c | 1 -
25-akpm/arch/sparc/mm/highmem.c | 2 +-
25-akpm/arch/sparc/mm/init.c | 2 --
25-akpm/arch/um/kernel/mem.c | 2 --
25-akpm/include/asm-ppc/highmem.h | 6 +++---
25-akpm/include/asm-sparc/highmem.h | 4 ++--
25-akpm/include/linux/highmem.h | 2 --
25-akpm/mm/memory.c | 2 --
25-akpm/net/core/dev.c | 2 +-
15 files changed, 14 insertions(+), 33 deletions(-)
diff -puN arch/i386/mm/discontig.c~kill-off-highmem_start_page arch/i386/mm/discontig.c
--- 25/arch/i386/mm/discontig.c~kill-off-highmem_start_page Wed Nov 17 14:17:42 2004
+++ 25-akpm/arch/i386/mm/discontig.c Wed Nov 17 14:17:42 2004
@@ -464,11 +464,6 @@ void __init set_highmem_pages_init(int b
void __init set_max_mapnr_init(void)
{
#ifdef CONFIG_HIGHMEM
- struct zone *high0 = &NODE_DATA(0)->node_zones[ZONE_HIGHMEM];
- if (high0->spanned_pages > 0)
- highmem_start_page = high0->zone_mem_map;
- else
- highmem_start_page = pfn_to_page(max_low_pfn - 1) + 1;
num_physpages = highend_pfn;
#else
num_physpages = max_low_pfn;
diff -puN arch/i386/mm/highmem.c~kill-off-highmem_start_page arch/i386/mm/highmem.c
--- 25/arch/i386/mm/highmem.c~kill-off-highmem_start_page Wed Nov 17 14:17:42 2004
+++ 25-akpm/arch/i386/mm/highmem.c Wed Nov 17 14:17:42 2004
@@ -3,7 +3,7 @@
void *kmap(struct page *page)
{
might_sleep();
- if (page < highmem_start_page)
+ if (!PageHighMem(page))
return page_address(page);
return kmap_high(page);
}
@@ -12,7 +12,7 @@ void kunmap(struct page *page)
{
if (in_interrupt())
BUG();
- if (page < highmem_start_page)
+ if (!PageHighMem(page))
return;
kunmap_high(page);
}
@@ -32,7 +32,7 @@ void *kmap_atomic(struct page *page, enu
/* even !CONFIG_PREEMPT needs this, for in_atomic in do_page_fault */
inc_preempt_count();
- if (page < highmem_start_page)
+ if (!PageHighMem(page))
return page_address(page);
idx = type + KM_TYPE_NR*smp_processor_id();
diff -puN arch/i386/mm/init.c~kill-off-highmem_start_page arch/i386/mm/init.c
--- 25/arch/i386/mm/init.c~kill-off-highmem_start_page Wed Nov 17 14:17:42 2004
+++ 25-akpm/arch/i386/mm/init.c Wed Nov 17 14:17:42 2004
@@ -549,7 +549,6 @@ void __init test_wp_bit(void)
static void __init set_max_mapnr_init(void)
{
#ifdef CONFIG_HIGHMEM
- highmem_start_page = pfn_to_page(highstart_pfn);
max_mapnr = num_physpages = highend_pfn;
#else
max_mapnr = num_physpages = max_low_pfn;
diff -puN arch/i386/mm/pageattr.c~kill-off-highmem_start_page arch/i386/mm/pageattr.c
--- 25/arch/i386/mm/pageattr.c~kill-off-highmem_start_page Wed Nov 17 14:17:42 2004
+++ 25-akpm/arch/i386/mm/pageattr.c Wed Nov 17 14:17:42 2004
@@ -105,10 +105,7 @@ __change_page_attr(struct page *page, pg
unsigned long address;
struct page *kpte_page;
-#ifdef CONFIG_HIGHMEM
- if (page >= highmem_start_page)
- BUG();
-#endif
+ BUG_ON(PageHighMem(page));
address = (unsigned long)page_address(page);
kpte = lookup_address(address);
diff -puN arch/mips/mm/highmem.c~kill-off-highmem_start_page arch/mips/mm/highmem.c
--- 25/arch/mips/mm/highmem.c~kill-off-highmem_start_page Wed Nov 17 14:17:42 2004
+++ 25-akpm/arch/mips/mm/highmem.c Wed Nov 17 14:17:42 2004
@@ -8,7 +8,7 @@ void *__kmap(struct page *page)
void *addr;
might_sleep();
- if (page < highmem_start_page)
+ if (!PageHighMem(page))
return page_address(page);
addr = kmap_high(page);
flush_tlb_one((unsigned long)addr);
@@ -20,7 +20,7 @@ void __kunmap(struct page *page)
{
if (in_interrupt())
BUG();
- if (page < highmem_start_page)
+ if (!PageHighMem(page))
return;
kunmap_high(page);
}
@@ -41,7 +41,7 @@ void *__kmap_atomic(struct page *page, e
/* even !CONFIG_PREEMPT needs this, for in_atomic in do_page_fault */
inc_preempt_count();
- if (page < highmem_start_page)
+ if (!PageHighMem(page))
return page_address(page);
idx = type + KM_TYPE_NR*smp_processor_id();
diff -puN arch/mips/mm/init.c~kill-off-highmem_start_page arch/mips/mm/init.c
--- 25/arch/mips/mm/init.c~kill-off-highmem_start_page Wed Nov 17 14:17:42 2004
+++ 25-akpm/arch/mips/mm/init.c Wed Nov 17 14:17:42 2004
@@ -204,7 +204,6 @@ void __init mem_init(void)
unsigned long tmp, ram;
#ifdef CONFIG_HIGHMEM
- highmem_start_page = mem_map + highstart_pfn;
#ifdef CONFIG_DISCONTIGMEM
#error "CONFIG_HIGHMEM and CONFIG_DISCONTIGMEM dont work together yet"
#endif
diff -puN arch/ppc/mm/init.c~kill-off-highmem_start_page arch/ppc/mm/init.c
--- 25/arch/ppc/mm/init.c~kill-off-highmem_start_page Wed Nov 17 14:17:42 2004
+++ 25-akpm/arch/ppc/mm/init.c Wed Nov 17 14:17:42 2004
@@ -419,7 +419,6 @@ void __init mem_init(void)
unsigned long highmem_mapnr;
highmem_mapnr = total_lowmem >> PAGE_SHIFT;
- highmem_start_page = mem_map + highmem_mapnr;
#endif /* CONFIG_HIGHMEM */
max_mapnr = total_memory >> PAGE_SHIFT;
diff -puN arch/sparc/mm/highmem.c~kill-off-highmem_start_page arch/sparc/mm/highmem.c
--- 25/arch/sparc/mm/highmem.c~kill-off-highmem_start_page Wed Nov 17 14:17:42 2004
+++ 25-akpm/arch/sparc/mm/highmem.c Wed Nov 17 14:17:42 2004
@@ -36,7 +36,7 @@ void *kmap_atomic(struct page *page, enu
/* even !CONFIG_PREEMPT needs this, for in_atomic in do_page_fault */
inc_preempt_count();
- if (page < highmem_start_page)
+ if (!PageHighMem(page))
return page_address(page);
idx = type + KM_TYPE_NR*smp_processor_id();
diff -puN arch/sparc/mm/init.c~kill-off-highmem_start_page arch/sparc/mm/init.c
--- 25/arch/sparc/mm/init.c~kill-off-highmem_start_page Wed Nov 17 14:17:42 2004
+++ 25-akpm/arch/sparc/mm/init.c Wed Nov 17 14:17:42 2004
@@ -402,8 +402,6 @@ void __init mem_init(void)
int reservedpages = 0;
int i;
- highmem_start_page = pfn_to_page(highstart_pfn);
-
if (PKMAP_BASE+LAST_PKMAP*PAGE_SIZE >= FIXADDR_START) {
prom_printf("BUG: fixmap and pkmap areas overlap\n");
prom_printf("pkbase: 0x%lx pkend: 0x%lx fixstart 0x%lx\n",
diff -puN arch/um/kernel/mem.c~kill-off-highmem_start_page arch/um/kernel/mem.c
--- 25/arch/um/kernel/mem.c~kill-off-highmem_start_page Wed Nov 17 14:17:42 2004
+++ 25-akpm/arch/um/kernel/mem.c Wed Nov 17 14:17:42 2004
@@ -49,8 +49,6 @@ static void setup_highmem(unsigned long
unsigned long highmem_pfn;
int i;
- highmem_start_page = virt_to_page(highmem_start);
-
highmem_pfn = __pa(highmem_start) >> PAGE_SHIFT;
for(i = 0; i < highmem_len >> PAGE_SHIFT; i++){
page = &mem_map[highmem_pfn + i];
diff -puN include/asm-ppc/highmem.h~kill-off-highmem_start_page include/asm-ppc/highmem.h
--- 25/include/asm-ppc/highmem.h~kill-off-highmem_start_page Wed Nov 17 14:17:42 2004
+++ 25-akpm/include/asm-ppc/highmem.h Wed Nov 17 14:17:42 2004
@@ -56,7 +56,7 @@ extern void kunmap_high(struct page *pag
static inline void *kmap(struct page *page)
{
might_sleep();
- if (page < highmem_start_page)
+ if (!PageHighMem(page))
return page_address(page);
return kmap_high(page);
}
@@ -64,7 +64,7 @@ static inline void *kmap(struct page *pa
static inline void kunmap(struct page *page)
{
BUG_ON(in_interrupt());
- if (page < highmem_start_page)
+ if (!PageHighMem(page))
return;
kunmap_high(page);
}
@@ -82,7 +82,7 @@ static inline void *kmap_atomic(struct p
/* even !CONFIG_PREEMPT needs this, for in_atomic in do_page_fault */
inc_preempt_count();
- if (page < highmem_start_page)
+ if (!PageHighMem(page))
return page_address(page);
idx = type + KM_TYPE_NR*smp_processor_id();
diff -puN include/asm-sparc/highmem.h~kill-off-highmem_start_page include/asm-sparc/highmem.h
--- 25/include/asm-sparc/highmem.h~kill-off-highmem_start_page Wed Nov 17 14:17:42 2004
+++ 25-akpm/include/asm-sparc/highmem.h Wed Nov 17 14:17:42 2004
@@ -57,7 +57,7 @@ extern void kunmap_high(struct page *pag
static inline void *kmap(struct page *page)
{
BUG_ON(in_interrupt());
- if (page < highmem_start_page)
+ if (!PageHighMem(page))
return page_address(page);
return kmap_high(page);
}
@@ -65,7 +65,7 @@ static inline void *kmap(struct page *pa
static inline void kunmap(struct page *page)
{
BUG_ON(in_interrupt());
- if (page < highmem_start_page)
+ if (!PageHighMem(page))
return;
kunmap_high(page);
}
diff -puN include/linux/highmem.h~kill-off-highmem_start_page include/linux/highmem.h
--- 25/include/linux/highmem.h~kill-off-highmem_start_page Wed Nov 17 14:17:42 2004
+++ 25-akpm/include/linux/highmem.h Wed Nov 17 14:17:42 2004
@@ -9,8 +9,6 @@
#ifdef CONFIG_HIGHMEM
-extern struct page *highmem_start_page;
-
#include <asm/highmem.h>
/* declarations for linux/mm/highmem.c */
diff -puN mm/memory.c~kill-off-highmem_start_page mm/memory.c
--- 25/mm/memory.c~kill-off-highmem_start_page Wed Nov 17 14:17:42 2004
+++ 25-akpm/mm/memory.c Wed Nov 17 14:17:42 2004
@@ -76,11 +76,9 @@ unsigned long num_physpages;
* and ZONE_HIGHMEM.
*/
void * high_memory;
-struct page *highmem_start_page;
unsigned long vmalloc_earlyreserve;
EXPORT_SYMBOL(num_physpages);
-EXPORT_SYMBOL(highmem_start_page);
EXPORT_SYMBOL(high_memory);
EXPORT_SYMBOL(vmalloc_earlyreserve);
diff -puN net/core/dev.c~kill-off-highmem_start_page net/core/dev.c
--- 25/net/core/dev.c~kill-off-highmem_start_page Wed Nov 17 14:17:42 2004
+++ 25-akpm/net/core/dev.c Wed Nov 17 14:17:42 2004
@@ -1119,7 +1119,7 @@ static inline int illegal_highdma(struct
return 0;
for (i = 0; i < skb_shinfo(skb)->nr_frags; i++)
- if (skb_shinfo(skb)->frags[i].page >= highmem_start_page)
+ if (PageHighMem(skb_shinfo(skb)->frags[i].page))
return 1;
return 0;
_