diff options
| author | Benjamin Herrenschmidt <benh@kernel.crashing.org> | 2008-06-11 15:37:10 +1000 |
|---|---|---|
| committer | Paul Mackerras <paulus@samba.org> | 2008-06-30 22:30:53 +1000 |
| commit | 41743a4e34f0777f51c1cf0675b91508ba143050 (patch) | |
| tree | 9e63c8c8d70169e6c8be699167234db33b102a1f /include | |
| parent | ff1f4ee94c3c4480b9cee95da2d19668262636c6 (diff) | |
powerpc: Free a PTE bit on ppc64 with 64K pages
This frees a PTE bit when using 64K pages on ppc64. This is done
by getting rid of the separate _PAGE_HASHPTE bit. Instead, we just test
if any of the 16 sub-page bits is set. For non-combo pages (ie. real
64K pages), we set SUB0 and the location encoding in that field.
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
Diffstat (limited to 'include')
| -rw-r--r-- | include/asm-powerpc/pgtable-4k.h | 1 | ||||
| -rw-r--r-- | include/asm-powerpc/pgtable-64k.h | 17 | ||||
| -rw-r--r-- | include/asm-powerpc/pgtable-ppc64.h | 1 |
3 files changed, 16 insertions, 3 deletions
diff --git a/include/asm-powerpc/pgtable-4k.h b/include/asm-powerpc/pgtable-4k.h index 818e2abc81e..fd2090dc1dc 100644 --- a/include/asm-powerpc/pgtable-4k.h +++ b/include/asm-powerpc/pgtable-4k.h @@ -41,6 +41,7 @@ #define PGDIR_MASK (~(PGDIR_SIZE-1)) /* PTE bits */ +#define _PAGE_HASHPTE 0x0400 /* software: pte has an associated HPTE */ #define _PAGE_SECONDARY 0x8000 /* software: HPTE is in secondary group */ #define _PAGE_GROUP_IX 0x7000 /* software: HPTE index within group */ #define _PAGE_F_SECOND _PAGE_SECONDARY diff --git a/include/asm-powerpc/pgtable-64k.h b/include/asm-powerpc/pgtable-64k.h index 1cbd6b377ee..c5007712473 100644 --- a/include/asm-powerpc/pgtable-64k.h +++ b/include/asm-powerpc/pgtable-64k.h @@ -75,6 +75,20 @@ static inline struct subpage_prot_table *pgd_subpage_prot(pgd_t *pgd) #define _PAGE_COMBO 0x10000000 /* this is a combo 4k page */ #define _PAGE_4K_PFN 0x20000000 /* PFN is for a single 4k page */ +/* For 64K page, we don't have a separate _PAGE_HASHPTE bit. Instead, + * we set that to be the whole sub-bits mask. The C code will only + * test this, so a multi-bit mask will work. For combo pages, this + * is equivalent as effectively, the old _PAGE_HASHPTE was an OR of + * all the sub bits. For real 64k pages, we now have the assembly set + * _PAGE_HPTE_SUB0 in addition to setting the HIDX bits which overlap + * that mask. This is fine as long as the HIDX bits are never set on + * a PTE that isn't hashed, which is the case today. + * + * A little nit is for the huge page C code, which does the hashing + * in C, we need to provide which bit to use. + */ +#define _PAGE_HASHPTE _PAGE_HPTE_SUB + /* Note the full page bits must be in the same location as for normal * 4k pages as the same asssembly will be used to insert 64K pages * wether the kernel has CONFIG_PPC_64K_PAGES or not @@ -83,8 +97,7 @@ static inline struct subpage_prot_table *pgd_subpage_prot(pgd_t *pgd) #define _PAGE_F_GIX 0x00007000 /* full page: hidx bits */ /* PTE flags to conserve for HPTE identification */ -#define _PAGE_HPTEFLAGS (_PAGE_BUSY | _PAGE_HASHPTE | _PAGE_HPTE_SUB |\ - _PAGE_COMBO) +#define _PAGE_HPTEFLAGS (_PAGE_BUSY | _PAGE_HASHPTE | _PAGE_COMBO) /* Shift to put page number into pte. * diff --git a/include/asm-powerpc/pgtable-ppc64.h b/include/asm-powerpc/pgtable-ppc64.h index cc6a43ba41d..2e48be841cc 100644 --- a/include/asm-powerpc/pgtable-ppc64.h +++ b/include/asm-powerpc/pgtable-ppc64.h @@ -91,7 +91,6 @@ #define _PAGE_DIRTY 0x0080 /* C: page changed */ #define _PAGE_ACCESSED 0x0100 /* R: page referenced */ #define _PAGE_RW 0x0200 /* software: user write access allowed */ -#define _PAGE_HASHPTE 0x0400 /* software: pte has an associated HPTE */ #define _PAGE_BUSY 0x0800 /* software: PTE & hash are busy */ #define _PAGE_BASE (_PAGE_PRESENT | _PAGE_ACCESSED | _PAGE_COHERENT) |