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changing include/asm-generic/pgtable.h for non-mmu

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There are some parts of include/asm-generic/pgtable.h that are relevant to
the non-mmu architectures.  To make it easier to include this from them I
would like to ifdef the relevant parts.

Without this there is a handful of functions that are referenced in here
that are not defined on many non-mmu architectures.  They could be defined
out of course, as an alternative approach.

Cc: David Howells <dhowells@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This commit is contained in:
Greg Ungerer 2007-08-10 13:01:20 -07:00 committed by Linus Torvalds
parent 73c59afc65
commit 9535239f6b
1 changed files with 38 additions and 35 deletions
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73
include/asm-generic/pgtable.h
View file

@ -2,6 +2,7 @@
#define _ASM_GENERIC_PGTABLE_H
#ifndef __ASSEMBLY__
#ifdef CONFIG_MMU
#ifndef __HAVE_ARCH_PTEP_SET_ACCESS_FLAGS
/*
@ -132,41 +133,6 @@ static inline void ptep_set_wrprotect(struct mm_struct *mm, unsigned long addres
#define move_pte(pte, prot, old_addr, new_addr) (pte)
#endif
/*
* A facility to provide lazy MMU batching. This allows PTE updates and
* page invalidations to be delayed until a call to leave lazy MMU mode
* is issued. Some architectures may benefit from doing this, and it is
* beneficial for both shadow and direct mode hypervisors, which may batch
* the PTE updates which happen during this window. Note that using this
* interface requires that read hazards be removed from the code. A read
* hazard could result in the direct mode hypervisor case, since the actual
* write to the page tables may not yet have taken place, so reads though
* a raw PTE pointer after it has been modified are not guaranteed to be
* up to date. This mode can only be entered and left under the protection of
* the page table locks for all page tables which may be modified. In the UP
* case, this is required so that preemption is disabled, and in the SMP case,
* it must synchronize the delayed page table writes properly on other CPUs.
*/
#ifndef __HAVE_ARCH_ENTER_LAZY_MMU_MODE
#define arch_enter_lazy_mmu_mode() do {} while (0)
#define arch_leave_lazy_mmu_mode() do {} while (0)
#define arch_flush_lazy_mmu_mode() do {} while (0)
#endif
/*
* A facility to provide batching of the reload of page tables with the
* actual context switch code for paravirtualized guests. By convention,
* only one of the lazy modes (CPU, MMU) should be active at any given
* time, entry should never be nested, and entry and exits should always
* be paired. This is for sanity of maintaining and reasoning about the
* kernel code.
*/
#ifndef __HAVE_ARCH_ENTER_LAZY_CPU_MODE
#define arch_enter_lazy_cpu_mode() do {} while (0)
#define arch_leave_lazy_cpu_mode() do {} while (0)
#define arch_flush_lazy_cpu_mode() do {} while (0)
#endif
/*
* When walking page tables, get the address of the next boundary,
* or the end address of the range if that comes earlier. Although no
@ -233,6 +199,43 @@ static inline int pmd_none_or_clear_bad(pmd_t *pmd)
}
return 0;
}
#endif /* CONFIG_MMU */
/*
* A facility to provide lazy MMU batching. This allows PTE updates and
* page invalidations to be delayed until a call to leave lazy MMU mode
* is issued. Some architectures may benefit from doing this, and it is
* beneficial for both shadow and direct mode hypervisors, which may batch
* the PTE updates which happen during this window. Note that using this
* interface requires that read hazards be removed from the code. A read
* hazard could result in the direct mode hypervisor case, since the actual
* write to the page tables may not yet have taken place, so reads though
* a raw PTE pointer after it has been modified are not guaranteed to be
* up to date. This mode can only be entered and left under the protection of
* the page table locks for all page tables which may be modified. In the UP
* case, this is required so that preemption is disabled, and in the SMP case,
* it must synchronize the delayed page table writes properly on other CPUs.
*/
#ifndef __HAVE_ARCH_ENTER_LAZY_MMU_MODE
#define arch_enter_lazy_mmu_mode() do {} while (0)
#define arch_leave_lazy_mmu_mode() do {} while (0)
#define arch_flush_lazy_mmu_mode() do {} while (0)
#endif
/*
* A facility to provide batching of the reload of page tables with the
* actual context switch code for paravirtualized guests. By convention,
* only one of the lazy modes (CPU, MMU) should be active at any given
* time, entry should never be nested, and entry and exits should always
* be paired. This is for sanity of maintaining and reasoning about the
* kernel code.
*/
#ifndef __HAVE_ARCH_ENTER_LAZY_CPU_MODE
#define arch_enter_lazy_cpu_mode() do {} while (0)
#define arch_leave_lazy_cpu_mode() do {} while (0)
#define arch_flush_lazy_cpu_mode() do {} while (0)
#endif
#endif /* !__ASSEMBLY__ */
#endif /* _ASM_GENERIC_PGTABLE_H */