| /* |
| * Page table support for the Hexagon architecture |
| * |
| * Copyright (c) 2010-2011, The Linux Foundation. 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) |
| return NULL; |
| if (!pgtable_page_ctor(pte)) { |
| __free_page(pte); |
| return NULL; |
| } |
| 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 |