Files
linux/include/asm-powerpc/page_64.h
David Gibson 5e391dc9e3 [PATCH] powerpc: fix for hugepage areas straddling 4GB boundary
Commit 7d24f0b8a5 fixed bugs in the ppc64 SLB
miss handler with respect to hugepage handling, and in the process tweaked
the semantics of the hugepage address masks in mm_context_t.

Unfortunately, it left out a couple of necessary changes to go with that
change.  First, the in_hugepage_area() macro was not updated to match,
second prepare_hugepage_range() was not updated to correctly handle
hugepages regions which straddled the 4GB point.

The latter appears only to cause process-hangs when attempting to map such
a region, but the former can cause oopses if a get_user_pages() is
triggered at the wrong point.  This patch addresses both bugs.

Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-11-23 16:08:39 -08:00

179 lines
5.3 KiB
C

#ifndef _ASM_POWERPC_PAGE_64_H
#define _ASM_POWERPC_PAGE_64_H
/*
* Copyright (C) 2001 PPC64 Team, IBM Corp
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License
* as published by the Free Software Foundation; either version
* 2 of the License, or (at your option) any later version.
*/
/*
* We always define HW_PAGE_SHIFT to 12 as use of 64K pages remains Linux
* specific, every notion of page number shared with the firmware, TCEs,
* iommu, etc... still uses a page size of 4K.
*/
#define HW_PAGE_SHIFT 12
#define HW_PAGE_SIZE (ASM_CONST(1) << HW_PAGE_SHIFT)
#define HW_PAGE_MASK (~(HW_PAGE_SIZE-1))
/*
* PAGE_FACTOR is the number of bits factor between PAGE_SHIFT and
* HW_PAGE_SHIFT, that is 4K pages.
*/
#define PAGE_FACTOR (PAGE_SHIFT - HW_PAGE_SHIFT)
#define REGION_SIZE 4UL
#define REGION_SHIFT 60UL
#define REGION_MASK (((1UL<<REGION_SIZE)-1UL)<<REGION_SHIFT)
#define VMALLOCBASE ASM_CONST(0xD000000000000000)
#define VMALLOC_REGION_ID (VMALLOCBASE >> REGION_SHIFT)
#define KERNEL_REGION_ID (KERNELBASE >> REGION_SHIFT)
#define USER_REGION_ID (0UL)
#define REGION_ID(ea) (((unsigned long)(ea)) >> REGION_SHIFT)
/* Segment size */
#define SID_SHIFT 28
#define SID_MASK 0xfffffffffUL
#define ESID_MASK 0xfffffffff0000000UL
#define GET_ESID(x) (((x) >> SID_SHIFT) & SID_MASK)
#ifndef __ASSEMBLY__
#include <asm/cache.h>
typedef unsigned long pte_basic_t;
static __inline__ void clear_page(void *addr)
{
unsigned long lines, line_size;
line_size = ppc64_caches.dline_size;
lines = ppc64_caches.dlines_per_page;
__asm__ __volatile__(
"mtctr %1 # clear_page\n\
1: dcbz 0,%0\n\
add %0,%0,%3\n\
bdnz+ 1b"
: "=r" (addr)
: "r" (lines), "0" (addr), "r" (line_size)
: "ctr", "memory");
}
extern void copy_4K_page(void *to, void *from);
#ifdef CONFIG_PPC_64K_PAGES
static inline void copy_page(void *to, void *from)
{
unsigned int i;
for (i=0; i < (1 << (PAGE_SHIFT - 12)); i++) {
copy_4K_page(to, from);
to += 4096;
from += 4096;
}
}
#else /* CONFIG_PPC_64K_PAGES */
static inline void copy_page(void *to, void *from)
{
copy_4K_page(to, from);
}
#endif /* CONFIG_PPC_64K_PAGES */
/* Log 2 of page table size */
extern u64 ppc64_pft_size;
/* Large pages size */
#ifdef CONFIG_HUGETLB_PAGE
extern unsigned int HPAGE_SHIFT;
#else
#define HPAGE_SHIFT PAGE_SHIFT
#endif
#define HPAGE_SIZE ((1UL) << HPAGE_SHIFT)
#define HPAGE_MASK (~(HPAGE_SIZE - 1))
#define HUGETLB_PAGE_ORDER (HPAGE_SHIFT - PAGE_SHIFT)
#endif /* __ASSEMBLY__ */
#ifdef CONFIG_HUGETLB_PAGE
#define HTLB_AREA_SHIFT 40
#define HTLB_AREA_SIZE (1UL << HTLB_AREA_SHIFT)
#define GET_HTLB_AREA(x) ((x) >> HTLB_AREA_SHIFT)
#define LOW_ESID_MASK(addr, len) (((1U << (GET_ESID(addr+len-1)+1)) \
- (1U << GET_ESID(addr))) & 0xffff)
#define HTLB_AREA_MASK(addr, len) (((1U << (GET_HTLB_AREA(addr+len-1)+1)) \
- (1U << GET_HTLB_AREA(addr))) & 0xffff)
#define ARCH_HAS_HUGEPAGE_ONLY_RANGE
#define ARCH_HAS_PREPARE_HUGEPAGE_RANGE
#define ARCH_HAS_SETCLEAR_HUGE_PTE
#define touches_hugepage_low_range(mm, addr, len) \
(LOW_ESID_MASK((addr), (len)) & (mm)->context.low_htlb_areas)
#define touches_hugepage_high_range(mm, addr, len) \
(HTLB_AREA_MASK((addr), (len)) & (mm)->context.high_htlb_areas)
#define __within_hugepage_low_range(addr, len, segmask) \
((LOW_ESID_MASK((addr), (len)) | (segmask)) == (segmask))
#define within_hugepage_low_range(addr, len) \
__within_hugepage_low_range((addr), (len), \
current->mm->context.low_htlb_areas)
#define __within_hugepage_high_range(addr, len, zonemask) \
((HTLB_AREA_MASK((addr), (len)) | (zonemask)) == (zonemask))
#define within_hugepage_high_range(addr, len) \
__within_hugepage_high_range((addr), (len), \
current->mm->context.high_htlb_areas)
#define is_hugepage_only_range(mm, addr, len) \
(touches_hugepage_high_range((mm), (addr), (len)) || \
touches_hugepage_low_range((mm), (addr), (len)))
#define HAVE_ARCH_HUGETLB_UNMAPPED_AREA
#define in_hugepage_area(context, addr) \
(cpu_has_feature(CPU_FTR_16M_PAGE) && \
( ( (addr) >= 0x100000000UL) \
? ((1 << GET_HTLB_AREA(addr)) & (context).high_htlb_areas) \
: ((1 << GET_ESID(addr)) & (context).low_htlb_areas) ) )
#else /* !CONFIG_HUGETLB_PAGE */
#define in_hugepage_area(mm, addr) 0
#endif /* !CONFIG_HUGETLB_PAGE */
#ifdef MODULE
#define __page_aligned __attribute__((__aligned__(PAGE_SIZE)))
#else
#define __page_aligned \
__attribute__((__aligned__(PAGE_SIZE), \
__section__(".data.page_aligned")))
#endif
#define VM_DATA_DEFAULT_FLAGS \
(test_thread_flag(TIF_32BIT) ? \
VM_DATA_DEFAULT_FLAGS32 : VM_DATA_DEFAULT_FLAGS64)
/*
* This is the default if a program doesn't have a PT_GNU_STACK
* program header entry. The PPC64 ELF ABI has a non executable stack
* stack by default, so in the absense of a PT_GNU_STACK program header
* we turn execute permission off.
*/
#define VM_STACK_DEFAULT_FLAGS32 (VM_READ | VM_WRITE | VM_EXEC | \
VM_MAYREAD | VM_MAYWRITE | VM_MAYEXEC)
#define VM_STACK_DEFAULT_FLAGS64 (VM_READ | VM_WRITE | \
VM_MAYREAD | VM_MAYWRITE | VM_MAYEXEC)
#define VM_STACK_DEFAULT_FLAGS \
(test_thread_flag(TIF_32BIT) ? \
VM_STACK_DEFAULT_FLAGS32 : VM_STACK_DEFAULT_FLAGS64)
#include <asm-generic/page.h>
#endif /* _ASM_POWERPC_PAGE_64_H */