From 5a7b4193e564d1611ecf1cd859aed60d5612d78f Mon Sep 17 00:00:00 2001 From: Benjamin Herrenschmidt Date: Wed, 2 Dec 2009 09:28:35 +1100 Subject: Revert "powerpc/mm: Fix bug in pagetable cache cleanup with CONFIG_PPC_SUBPAGE_PROT" This reverts commit c045256d146800ea1d741a8e9e377dada6b7e195. It breaks build when CONFIG_PPC_SUBPAGE_PROT is not set. I will commit a fixed version separately Signed-off-by: Benjamin Herrenschmidt --- arch/powerpc/include/asm/pte-hash64-64k.h | 37 +++++++++++++++++++++++++++++++ 1 file changed, 37 insertions(+) (limited to 'arch/powerpc/include/asm/pte-hash64-64k.h') diff --git a/arch/powerpc/include/asm/pte-hash64-64k.h b/arch/powerpc/include/asm/pte-hash64-64k.h index c4490f9c67c4..82b72207c51c 100644 --- a/arch/powerpc/include/asm/pte-hash64-64k.h +++ b/arch/powerpc/include/asm/pte-hash64-64k.h @@ -76,4 +76,41 @@ remap_pfn_range((vma), (addr), (pfn), PAGE_SIZE, \ __pgprot(pgprot_val((prot)) | _PAGE_4K_PFN)) + +#ifdef CONFIG_PPC_SUBPAGE_PROT +/* + * For the sub-page protection option, we extend the PGD with one of + * these. Basically we have a 3-level tree, with the top level being + * the protptrs array. To optimize speed and memory consumption when + * only addresses < 4GB are being protected, pointers to the first + * four pages of sub-page protection words are stored in the low_prot + * array. + * Each page of sub-page protection words protects 1GB (4 bytes + * protects 64k). For the 3-level tree, each page of pointers then + * protects 8TB. + */ +struct subpage_prot_table { + unsigned long maxaddr; /* only addresses < this are protected */ + unsigned int **protptrs[2]; + unsigned int *low_prot[4]; +}; + +#undef PGD_TABLE_SIZE +#define PGD_TABLE_SIZE ((sizeof(pgd_t) << PGD_INDEX_SIZE) + \ + sizeof(struct subpage_prot_table)) + +#define SBP_L1_BITS (PAGE_SHIFT - 2) +#define SBP_L2_BITS (PAGE_SHIFT - 3) +#define SBP_L1_COUNT (1 << SBP_L1_BITS) +#define SBP_L2_COUNT (1 << SBP_L2_BITS) +#define SBP_L2_SHIFT (PAGE_SHIFT + SBP_L1_BITS) +#define SBP_L3_SHIFT (SBP_L2_SHIFT + SBP_L2_BITS) + +extern void subpage_prot_free(pgd_t *pgd); + +static inline struct subpage_prot_table *pgd_subpage_prot(pgd_t *pgd) +{ + return (struct subpage_prot_table *)(pgd + PTRS_PER_PGD); +} +#endif /* CONFIG_PPC_SUBPAGE_PROT */ #endif /* __ASSEMBLY__ */ -- cgit v1.2.3-59-g8ed1b