コード例 #1
0
ファイル: mmu.c プロジェクト: 0x00evil/linux
static int stage2_set_pmd_huge(struct kvm *kvm, struct kvm_mmu_memory_cache
			       *cache, phys_addr_t addr, const pmd_t *new_pmd)
{
	pmd_t *pmd, old_pmd;

	pmd = stage2_get_pmd(kvm, cache, addr);
	VM_BUG_ON(!pmd);

	/*
	 * Mapping in huge pages should only happen through a fault.  If a
	 * page is merged into a transparent huge page, the individual
	 * subpages of that huge page should be unmapped through MMU
	 * notifiers before we get here.
	 *
	 * Merging of CompoundPages is not supported; they should become
	 * splitting first, unmapped, merged, and mapped back in on-demand.
	 */
	VM_BUG_ON(pmd_present(*pmd) && pmd_pfn(*pmd) != pmd_pfn(*new_pmd));

	old_pmd = *pmd;
	kvm_set_pmd(pmd, *new_pmd);
	if (pmd_present(old_pmd))
		kvm_tlb_flush_vmid_ipa(kvm, addr);
	else
		get_page(virt_to_page(pmd));
	return 0;
}
コード例 #2
0
ファイル: init_64.c プロジェクト: PennPanda/linux-repo
int kern_addr_valid(unsigned long addr) 
{ 
	unsigned long above = ((long)addr) >> __VIRTUAL_MASK_SHIFT;
       pgd_t *pgd;
       pud_t *pud;
       pmd_t *pmd;
       pte_t *pte;

	if (above != 0 && above != -1UL)
		return 0; 
	
	pgd = pgd_offset_k(addr);
	if (pgd_none(*pgd))
		return 0;

	pud = pud_offset(pgd, addr);
	if (pud_none(*pud))
		return 0; 

	pmd = pmd_offset(pud, addr);
	if (pmd_none(*pmd))
		return 0;
	if (pmd_large(*pmd))
		return pfn_valid(pmd_pfn(*pmd));

	pte = pte_offset_kernel(pmd, addr);
	if (pte_none(*pte))
		return 0;
	return pfn_valid(pte_pfn(*pte));
}
コード例 #3
0
ファイル: page_tables.c プロジェクト: CSCLOG/beaglebone
/* Follow the PMD to the PTE. */
static unsigned long gpte_addr(struct lg_cpu *cpu,
			       pmd_t gpmd, unsigned long vaddr)
{
	unsigned long gpage = pmd_pfn(gpmd) << PAGE_SHIFT;

	BUG_ON(!(pmd_flags(gpmd) & _PAGE_PRESENT));
	return gpage + pte_index(vaddr) * sizeof(pte_t);
}
コード例 #4
0
ファイル: mmu.c プロジェクト: TheGalaxyProject/tgpkernel-s7-o
static int stage2_set_pmd_huge(struct kvm *kvm, struct kvm_mmu_memory_cache
			       *cache, phys_addr_t addr, const pmd_t *new_pmd)
{
	pmd_t *pmd, old_pmd;

	pmd = stage2_get_pmd(kvm, cache, addr);
	VM_BUG_ON(!pmd);

	old_pmd = *pmd;
	if (pmd_present(old_pmd)) {
		/*
		 * Multiple vcpus faulting on the same PMD entry, can
		 * lead to them sequentially updating the PMD with the
		 * same value. Following the break-before-make
		 * (pmd_clear() followed by tlb_flush()) process can
		 * hinder forward progress due to refaults generated
		 * on missing translations.
		 *
		 * Skip updating the page table if the entry is
		 * unchanged.
		 */
		if (pmd_val(old_pmd) == pmd_val(*new_pmd))
			return 0;

		/*
		 * Mapping in huge pages should only happen through a
		 * fault.  If a page is merged into a transparent huge
		 * page, the individual subpages of that huge page
		 * should be unmapped through MMU notifiers before we
		 * get here.
		 *
		 * Merging of CompoundPages is not supported; they
		 * should become splitting first, unmapped, merged,
		 * and mapped back in on-demand.
		 */
		VM_BUG_ON(pmd_pfn(old_pmd) != pmd_pfn(*new_pmd));

		pmd_clear(pmd);
		kvm_tlb_flush_vmid_ipa(kvm, addr);
	} else {
		get_page(virt_to_page(pmd));
	}

	kvm_set_pmd(pmd, *new_pmd);
	return 0;
}
コード例 #5
0
ファイル: page_tables.c プロジェクト: 020gzh/linux
static bool check_gpmd(struct lg_cpu *cpu, pmd_t gpmd)
{
	if ((pmd_flags(gpmd) & ~_PAGE_TABLE) ||
	    (pmd_pfn(gpmd) >= cpu->lg->pfn_limit)) {
		kill_guest(cpu, "bad page middle directory entry");
		return false;
	}
	return true;
}
コード例 #6
0
ファイル: mmu.c プロジェクト: BrainFucking/linux
/*
 * remap a PMD into pages
 */
static void split_pmd(pmd_t *pmd, pte_t *pte)
{
	unsigned long pfn = pmd_pfn(*pmd);
	int i = 0;

	do {
		/*
		 * Need to have the least restrictive permissions available
		 * permissions will be fixed up later
		 */
		set_pte(pte, pfn_pte(pfn, PAGE_KERNEL_EXEC));
		pfn++;
	} while (pte++, i++, i < PTRS_PER_PTE);
}
コード例 #7
0
ファイル: page_tables.c プロジェクト: CSCLOG/beaglebone
static void release_pmd(pmd_t *spmd)
{
	/* If the entry's not present, there's nothing to release. */
	if (pmd_flags(*spmd) & _PAGE_PRESENT) {
		unsigned int i;
		pte_t *ptepage = __va(pmd_pfn(*spmd) << PAGE_SHIFT);
		/* For each entry in the page, we might need to release it. */
		for (i = 0; i < PTRS_PER_PTE; i++)
			release_pte(ptepage[i]);
		/* Now we can free the page of PTEs */
		free_page((long)ptepage);
		/* And zero out the PMD entry so we never release it twice. */
		set_pmd(spmd, __pmd(0));
	}
}
コード例 #8
0
ファイル: page_tables.c プロジェクト: CSCLOG/beaglebone
/*
 * This routine then takes the page directory entry returned above, which
 * contains the address of the page table entry (PTE) page.  It then returns a
 * pointer to the PTE entry for the given address.
 */
static pte_t *spte_addr(struct lg_cpu *cpu, pgd_t spgd, unsigned long vaddr)
{
#ifdef CONFIG_X86_PAE
	pmd_t *pmd = spmd_addr(cpu, spgd, vaddr);
	pte_t *page = __va(pmd_pfn(*pmd) << PAGE_SHIFT);

	/* You should never call this if the PMD entry wasn't valid */
	BUG_ON(!(pmd_flags(*pmd) & _PAGE_PRESENT));
#else
	pte_t *page = __va(pgd_pfn(spgd) << PAGE_SHIFT);
	/* You should never call this if the PGD entry wasn't valid */
	BUG_ON(!(pgd_flags(spgd) & _PAGE_PRESENT));
#endif

	return &page[pte_index(vaddr)];
}
コード例 #9
0
ファイル: page_tables.c プロジェクト: CSCLOG/beaglebone
static void check_gpmd(struct lg_cpu *cpu, pmd_t gpmd)
{
	if ((pmd_flags(gpmd) & ~_PAGE_TABLE) ||
	   (pmd_pfn(gpmd) >= cpu->lg->pfn_limit))
		kill_guest(cpu, "bad page middle directory entry");
}
コード例 #10
0
ファイル: hugepage-hash64.c プロジェクト: 03199618/linux
int __hash_page_thp(unsigned long ea, unsigned long access, unsigned long vsid,
		    pmd_t *pmdp, unsigned long trap, int local, int ssize,
		    unsigned int psize)
{
	unsigned int index, valid;
	unsigned char *hpte_slot_array;
	unsigned long rflags, pa, hidx;
	unsigned long old_pmd, new_pmd;
	int ret, lpsize = MMU_PAGE_16M;
	unsigned long vpn, hash, shift, slot;

	/*
	 * atomically mark the linux large page PMD busy and dirty
	 */
	do {
		old_pmd = pmd_val(*pmdp);
		/* If PMD busy, retry the access */
		if (unlikely(old_pmd & _PAGE_BUSY))
			return 0;
		/* If PMD is trans splitting retry the access */
		if (unlikely(old_pmd & _PAGE_SPLITTING))
			return 0;
		/* If PMD permissions don't match, take page fault */
		if (unlikely(access & ~old_pmd))
			return 1;
		/*
		 * Try to lock the PTE, add ACCESSED and DIRTY if it was
		 * a write access
		 */
		new_pmd = old_pmd | _PAGE_BUSY | _PAGE_ACCESSED;
		if (access & _PAGE_RW)
			new_pmd |= _PAGE_DIRTY;
	} while (old_pmd != __cmpxchg_u64((unsigned long *)pmdp,
					  old_pmd, new_pmd));
	/*
	 * PP bits. _PAGE_USER is already PP bit 0x2, so we only
	 * need to add in 0x1 if it's a read-only user page
	 */
	rflags = new_pmd & _PAGE_USER;
	if ((new_pmd & _PAGE_USER) && !((new_pmd & _PAGE_RW) &&
					   (new_pmd & _PAGE_DIRTY)))
		rflags |= 0x1;
	/*
	 * _PAGE_EXEC -> HW_NO_EXEC since it's inverted
	 */
	rflags |= ((new_pmd & _PAGE_EXEC) ? 0 : HPTE_R_N);

#if 0
	if (!cpu_has_feature(CPU_FTR_COHERENT_ICACHE)) {

		/*
		 * No CPU has hugepages but lacks no execute, so we
		 * don't need to worry about that case
		 */
		rflags = hash_page_do_lazy_icache(rflags, __pte(old_pte), trap);
	}
#endif
	/*
	 * Find the slot index details for this ea, using base page size.
	 */
	shift = mmu_psize_defs[psize].shift;
	index = (ea & ~HPAGE_PMD_MASK) >> shift;
	BUG_ON(index >= 4096);

	vpn = hpt_vpn(ea, vsid, ssize);
	hash = hpt_hash(vpn, shift, ssize);
	hpte_slot_array = get_hpte_slot_array(pmdp);

	valid = hpte_valid(hpte_slot_array, index);
	if (valid) {
		/* update the hpte bits */
		hidx =  hpte_hash_index(hpte_slot_array, index);
		if (hidx & _PTEIDX_SECONDARY)
			hash = ~hash;
		slot = (hash & htab_hash_mask) * HPTES_PER_GROUP;
		slot += hidx & _PTEIDX_GROUP_IX;

		ret = ppc_md.hpte_updatepp(slot, rflags, vpn,
					   psize, lpsize, ssize, local);
		/*
		 * We failed to update, try to insert a new entry.
		 */
		if (ret == -1) {
			/*
			 * large pte is marked busy, so we can be sure
			 * nobody is looking at hpte_slot_array. hence we can
			 * safely update this here.
			 */
			valid = 0;
			new_pmd &= ~_PAGE_HPTEFLAGS;
			hpte_slot_array[index] = 0;
		} else
			/* clear the busy bits and set the hash pte bits */
			new_pmd = (new_pmd & ~_PAGE_HPTEFLAGS) | _PAGE_HASHPTE;
	}

	if (!valid) {
		unsigned long hpte_group;

		/* insert new entry */
		pa = pmd_pfn(__pmd(old_pmd)) << PAGE_SHIFT;
repeat:
		hpte_group = ((hash & htab_hash_mask) * HPTES_PER_GROUP) & ~0x7UL;

		/* clear the busy bits and set the hash pte bits */
		new_pmd = (new_pmd & ~_PAGE_HPTEFLAGS) | _PAGE_HASHPTE;

		/* Add in WIMG bits */
		rflags |= (new_pmd & (_PAGE_WRITETHRU | _PAGE_NO_CACHE |
				      _PAGE_COHERENT | _PAGE_GUARDED));

		/* Insert into the hash table, primary slot */
		slot = ppc_md.hpte_insert(hpte_group, vpn, pa, rflags, 0,
					  psize, lpsize, ssize);
		/*
		 * Primary is full, try the secondary
		 */
		if (unlikely(slot == -1)) {
			hpte_group = ((~hash & htab_hash_mask) *
				      HPTES_PER_GROUP) & ~0x7UL;
			slot = ppc_md.hpte_insert(hpte_group, vpn, pa,
						  rflags, HPTE_V_SECONDARY,
						  psize, lpsize, ssize);
			if (slot == -1) {
				if (mftb() & 0x1)
					hpte_group = ((hash & htab_hash_mask) *
						      HPTES_PER_GROUP) & ~0x7UL;

				ppc_md.hpte_remove(hpte_group);
				goto repeat;
			}
		}
		/*
		 * Hypervisor failure. Restore old pmd and return -1
		 * similar to __hash_page_*
		 */
		if (unlikely(slot == -2)) {
			*pmdp = __pmd(old_pmd);
			hash_failure_debug(ea, access, vsid, trap, ssize,
					   psize, lpsize, old_pmd);
			return -1;
		}
		/*
		 * large pte is marked busy, so we can be sure
		 * nobody is looking at hpte_slot_array. hence we can
		 * safely update this here.
		 */
		mark_hpte_slot_valid(hpte_slot_array, index, slot);
	}
	/*
	 * No need to use ldarx/stdcx here
	 */
	*pmdp = __pmd(new_pmd & ~_PAGE_BUSY);
	return 0;
}