diff options
| author | Ralf Baechle <ralf@linux-mips.org> | 2009-04-25 11:25:34 +0200 |
|---|---|---|
| committer | Ralf Baechle <ralf@linux-mips.org> | 2009-05-14 13:50:29 +0100 |
| commit | bb86bf28aec6d0a207ae09f38a43e94133d4d6db (patch) | |
| tree | 34bd8f653eb10dc4eb82aa8ef2576475346070e1 /arch/mips/mm/highmem.c | |
| parent | 0b54352600b820a6d25f151cbd8975ed9b2aeb09 (diff) | |
MIPS: Fix highmem.
Commit 351336929ccf222ae38ff0cb7a8dd5fd5c6236a0 (kernel.org) rsp.
b3594a089f1c17ff919f8f78505c3f20e1f6f8ce (linux-mips.org):
> From: Chris Dearman <chris@mips.com>
> Date: Wed, 19 Sep 2007 00:58:24 +0100
> Subject: [PATCH] [MIPS] Allow setting of the cache attribute at run time.
>
> Slightly tacky, but there is a precedent in the sparc archirecture code.
introduces the variable _page_cachable_default, which defaults to zero and.
is used to create the prototype PTE for __kmap_atomic in
arch/mips/mm/init.c:kmap_init before initialization in
arch/mips/mm/c-r4k.c:coherency_setup, so the default value of 0 will be
used as the CCA of kmap atomic pages which on many processors is not a
defined CCA value and may result in writes to kmap_atomic pages getting
corrupted. Debugged by Jon Fraser (jfraser@broadcom.com).
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Diffstat (limited to 'arch/mips/mm/highmem.c')
| -rw-r--r-- | arch/mips/mm/highmem.c | 25 |
1 files changed, 19 insertions, 6 deletions
diff --git a/arch/mips/mm/highmem.c b/arch/mips/mm/highmem.c index 4481656d1065..2b1309b2580a 100644 --- a/arch/mips/mm/highmem.c +++ b/arch/mips/mm/highmem.c @@ -1,7 +1,12 @@ #include <linux/module.h> #include <linux/highmem.h> +#include <asm/fixmap.h> #include <asm/tlbflush.h> +static pte_t *kmap_pte; + +unsigned long highstart_pfn, highend_pfn; + void *__kmap(struct page *page) { void *addr; @@ -14,6 +19,7 @@ void *__kmap(struct page *page) return addr; } +EXPORT_SYMBOL(__kmap); void __kunmap(struct page *page) { @@ -22,6 +28,7 @@ void __kunmap(struct page *page) return; kunmap_high(page); } +EXPORT_SYMBOL(__kunmap); /* * kmap_atomic/kunmap_atomic is significantly faster than kmap/kunmap because @@ -48,11 +55,12 @@ void *__kmap_atomic(struct page *page, enum km_type type) #ifdef CONFIG_DEBUG_HIGHMEM BUG_ON(!pte_none(*(kmap_pte - idx))); #endif - set_pte(kmap_pte-idx, mk_pte(page, kmap_prot)); + set_pte(kmap_pte-idx, mk_pte(page, PAGE_KERNEL)); local_flush_tlb_one((unsigned long)vaddr); return (void*) vaddr; } +EXPORT_SYMBOL(__kmap_atomic); void __kunmap_atomic(void *kvaddr, enum km_type type) { @@ -77,6 +85,7 @@ void __kunmap_atomic(void *kvaddr, enum km_type type) pagefault_enable(); } +EXPORT_SYMBOL(__kunmap_atomic); /* * This is the same as kmap_atomic() but can map memory that doesn't @@ -92,7 +101,7 @@ void *kmap_atomic_pfn(unsigned long pfn, enum km_type type) debug_kmap_atomic(type); idx = type + KM_TYPE_NR*smp_processor_id(); vaddr = __fix_to_virt(FIX_KMAP_BEGIN + idx); - set_pte(kmap_pte-idx, pfn_pte(pfn, kmap_prot)); + set_pte(kmap_pte-idx, pfn_pte(pfn, PAGE_KERNEL)); flush_tlb_one(vaddr); return (void*) vaddr; @@ -111,7 +120,11 @@ struct page *__kmap_atomic_to_page(void *ptr) return pte_page(*pte); } -EXPORT_SYMBOL(__kmap); -EXPORT_SYMBOL(__kunmap); -EXPORT_SYMBOL(__kmap_atomic); -EXPORT_SYMBOL(__kunmap_atomic); +void __init kmap_init(void) +{ + unsigned long kmap_vstart; + + /* cache the first kmap pte */ + kmap_vstart = __fix_to_virt(FIX_KMAP_BEGIN); + kmap_pte = kmap_get_fixmap_pte(kmap_vstart); +} |