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author | Richard Kuo <rkuo@codeaurora.org> | 2011-10-31 23:53:38 (GMT) |
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committer | Linus Torvalds <torvalds@linux-foundation.org> | 2011-11-01 14:34:20 (GMT) |
commit | a7e79840991eac8da36f437c653ee4b8cfbdafdc (patch) | |
tree | a673266d06a67c7f4f32b0e048848e752b6bb441 /arch/hexagon/include/asm/pgalloc.h | |
parent | b7f3785fbb3df3307290d4c236ffaa7ad172b6ed (diff) | |
download | linux-a7e79840991eac8da36f437c653ee4b8cfbdafdc.tar.xz |
Hexagon: Add page table header files & etc.
Signed-off-by: Richard Kuo <rkuo@codeaurora.org>
Signed-off-by: Linas Vepstas <linas@codeaurora.org>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'arch/hexagon/include/asm/pgalloc.h')
-rw-r--r-- | arch/hexagon/include/asm/pgalloc.h | 146 |
1 files changed, 146 insertions, 0 deletions
diff --git a/arch/hexagon/include/asm/pgalloc.h b/arch/hexagon/include/asm/pgalloc.h new file mode 100644 index 0000000..13443c7 --- /dev/null +++ b/arch/hexagon/include/asm/pgalloc.h @@ -0,0 +1,146 @@ +/* + * Page table support for the Hexagon architecture + * + * Copyright (c) 2010-2011, Code Aurora Forum. All rights reserved. + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 and + * only version 2 as published by the Free Software Foundation. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, write to the Free Software + * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA + * 02110-1301, USA. + */ + +#ifndef _ASM_PGALLOC_H +#define _ASM_PGALLOC_H + +#include <asm/mem-layout.h> +#include <asm/atomic.h> + +#define check_pgt_cache() do {} while (0) + +extern unsigned long long kmap_generation; + +/* + * Page table creation interface + */ +static inline pgd_t *pgd_alloc(struct mm_struct *mm) +{ + pgd_t *pgd; + + pgd = (pgd_t *)__get_free_page(GFP_KERNEL | __GFP_ZERO); + + /* + * There may be better ways to do this, but to ensure + * that new address spaces always contain the kernel + * base mapping, and to ensure that the user area is + * initially marked invalid, initialize the new map + * map with a copy of the kernel's persistent map. + */ + + memcpy(pgd, swapper_pg_dir, PTRS_PER_PGD*sizeof(pgd_t *)); + mm->context.generation = kmap_generation; + + /* Physical version is what is passed to virtual machine on switch */ + mm->context.ptbase = __pa(pgd); + + return pgd; +} + +static inline void pgd_free(struct mm_struct *mm, pgd_t *pgd) +{ + free_page((unsigned long) pgd); +} + +static inline struct page *pte_alloc_one(struct mm_struct *mm, + unsigned long address) +{ + struct page *pte; + + pte = alloc_page(GFP_KERNEL | __GFP_REPEAT | __GFP_ZERO); + + if (pte) + pgtable_page_ctor(pte); + + return pte; +} + +/* _kernel variant gets to use a different allocator */ +static inline pte_t *pte_alloc_one_kernel(struct mm_struct *mm, + unsigned long address) +{ + gfp_t flags = GFP_KERNEL | __GFP_REPEAT | __GFP_ZERO; + return (pte_t *) __get_free_page(flags); +} + +static inline void pte_free(struct mm_struct *mm, struct page *pte) +{ + pgtable_page_dtor(pte); + __free_page(pte); +} + +static inline void pte_free_kernel(struct mm_struct *mm, pte_t *pte) +{ + free_page((unsigned long)pte); +} + +static inline void pmd_populate(struct mm_struct *mm, pmd_t *pmd, + pgtable_t pte) +{ + /* + * Conveniently, zero in 3 LSB means indirect 4K page table. + * Not so convenient when you're trying to vary the page size. + */ + set_pmd(pmd, __pmd(((unsigned long)page_to_pfn(pte) << PAGE_SHIFT) | + HEXAGON_L1_PTE_SIZE)); +} + +/* + * Other architectures seem to have ways of making all processes + * share the same pmd's for their kernel mappings, but the v0.3 + * Hexagon VM spec has a "monolithic" L1 table for user and kernel + * segments. We track "generations" of the kernel map to minimize + * overhead, and update the "slave" copies of the kernel mappings + * as part of switch_mm. However, we still need to update the + * kernel map of the active thread who's calling pmd_populate_kernel... + */ +static inline void pmd_populate_kernel(struct mm_struct *mm, pmd_t *pmd, + pte_t *pte) +{ + extern spinlock_t kmap_gen_lock; + pmd_t *ppmd; + int pmdindex; + + spin_lock(&kmap_gen_lock); + kmap_generation++; + mm->context.generation = kmap_generation; + current->active_mm->context.generation = kmap_generation; + spin_unlock(&kmap_gen_lock); + + set_pmd(pmd, __pmd(((unsigned long)__pa(pte)) | HEXAGON_L1_PTE_SIZE)); + + /* + * Now the "slave" copy of the current thread. + * This is pointer arithmetic, not byte addresses! + */ + pmdindex = (pgd_t *)pmd - mm->pgd; + ppmd = (pmd_t *)current->active_mm->pgd + pmdindex; + set_pmd(ppmd, __pmd(((unsigned long)__pa(pte)) | HEXAGON_L1_PTE_SIZE)); + if (pmdindex > max_kernel_seg) + max_kernel_seg = pmdindex; +} + +#define __pte_free_tlb(tlb, pte, addr) \ +do { \ + pgtable_page_dtor((pte)); \ + tlb_remove_page((tlb), (pte)); \ +} while (0) + +#endif |