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authorLiu Hua <sdu.liu@huawei.com>2014-04-18 09:43:32 +0100
committerRussell King <rmk+kernel@arm.linux.org.uk>2014-04-23 11:09:42 +0100
commita05e54c103b0b8e1dab5d04b411f1d48387c4903 (patch)
treed9960fd5c3517f42f57c4513e28dd51a6353ec27 /arch/arm/mm/highmem.c
parent4221e2e6b3160e4b558df14fa79f025c0e277935 (diff)
downloadlinux-a05e54c103b0b8e1dab5d04b411f1d48387c4903.tar.bz2
ARM: 8031/2: change fixmap mapping region to support 32 CPUs
In 32-bit ARM systems, the fixmap mapping region can support no more than 14 CPUs(total: 896k; one CPU: 64K). And we can configure NR_CPUS up to 32. So there is a mismatch. This patch moves fixmapping region downwards to region 0xffc00000- 0xffe00000. Then the fixmap mapping region can support up to 32 CPUs. Reviewed-by: Nicolas Pitre <nico@linaro.org> Signed-off-by: Liu Hua <sdu.liu@huawei.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Diffstat (limited to 'arch/arm/mm/highmem.c')
-rw-r--r--arch/arm/mm/highmem.c27
1 files changed, 21 insertions, 6 deletions
diff --git a/arch/arm/mm/highmem.c b/arch/arm/mm/highmem.c
index e05e8ad26ba5..45aeaaca9052 100644
--- a/arch/arm/mm/highmem.c
+++ b/arch/arm/mm/highmem.c
@@ -18,6 +18,21 @@
#include <asm/tlbflush.h>
#include "mm.h"
+pte_t *fixmap_page_table;
+
+static inline void set_fixmap_pte(int idx, pte_t pte)
+{
+ unsigned long vaddr = __fix_to_virt(idx);
+ set_pte_ext(fixmap_page_table + idx, pte, 0);
+ local_flush_tlb_kernel_page(vaddr);
+}
+
+static inline pte_t get_fixmap_pte(unsigned long vaddr)
+{
+ unsigned long idx = __virt_to_fix(vaddr);
+ return *(fixmap_page_table + idx);
+}
+
void *kmap(struct page *page)
{
might_sleep();
@@ -69,14 +84,14 @@ void *kmap_atomic(struct page *page)
* With debugging enabled, kunmap_atomic forces that entry to 0.
* Make sure it was indeed properly unmapped.
*/
- BUG_ON(!pte_none(get_top_pte(vaddr)));
+ BUG_ON(!pte_none(*(fixmap_page_table + idx)));
#endif
/*
* When debugging is off, kunmap_atomic leaves the previous mapping
* in place, so the contained TLB flush ensures the TLB is updated
* with the new mapping.
*/
- set_top_pte(vaddr, mk_pte(page, kmap_prot));
+ set_fixmap_pte(idx, mk_pte(page, kmap_prot));
return (void *)vaddr;
}
@@ -95,7 +110,7 @@ void __kunmap_atomic(void *kvaddr)
__cpuc_flush_dcache_area((void *)vaddr, PAGE_SIZE);
#ifdef CONFIG_DEBUG_HIGHMEM
BUG_ON(vaddr != __fix_to_virt(idx));
- set_top_pte(vaddr, __pte(0));
+ set_fixmap_pte(idx, __pte(0));
#else
(void) idx; /* to kill a warning */
#endif
@@ -119,9 +134,9 @@ void *kmap_atomic_pfn(unsigned long pfn)
idx = type + KM_TYPE_NR * smp_processor_id();
vaddr = __fix_to_virt(idx);
#ifdef CONFIG_DEBUG_HIGHMEM
- BUG_ON(!pte_none(get_top_pte(vaddr)));
+ BUG_ON(!pte_none(*(fixmap_page_table + idx)));
#endif
- set_top_pte(vaddr, pfn_pte(pfn, kmap_prot));
+ set_fixmap_pte(idx, pfn_pte(pfn, kmap_prot));
return (void *)vaddr;
}
@@ -133,5 +148,5 @@ struct page *kmap_atomic_to_page(const void *ptr)
if (vaddr < FIXADDR_START)
return virt_to_page(ptr);
- return pte_page(get_top_pte(vaddr));
+ return pte_page(get_fixmap_pte(vaddr));
}