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(I'm so sorry!) Linux kernel mirror (for testing) git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel os linux
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12345678910111213141516171819202122232425262728293031323334353637383940414243444546474849505152535455565758596061626364656667686970717273747576777879808182838485868788899091929394/* SPDX-License-Identifier: GPL-2.0-only *//* * Page table support for the Hexagon architecture * * Copyright (c) 2010-2011, The Linux Foundation. All rights reserved. */
#ifndef _ASM_PGALLOC_H#define _ASM_PGALLOC_H
#include <asm/mem-layout.h>#include <asm/atomic.h>
#include <asm-generic/pgalloc.h>
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_alloc(mm, 0);
/* * 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 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) \ tlb_remove_ptdesc((tlb), page_ptdesc(pte))
#endif