Commit 16c2d476 authored by Benjamin Herrenschmidt's avatar Benjamin Herrenschmidt Committed by Paul Mackerras
Browse files

[POWERPC] Add ability to 4K kernel to hash in 64K pages 



This adds the ability for a kernel compiled with 4K page size
to have special slices containing 64K pages and hash the right type
of hash PTEs.

Signed-off-by: default avatarBenjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: default avatarPaul Mackerras <paulus@samba.org>
parent d0f13e3c

arch/powerpc/Kconfig

+6 −0
Original line number Diff line number Diff line
@@ -546,9 +546,15 @@ config NODES_SPAN_OTHER_NODES 
	def_bool y

	depends on NEED_MULTIPLE_NODES



config PPC_HAS_HASH_64K

	bool

	depends on PPC64

	default n



config PPC_64K_PAGES

	bool "64k page size"

	depends on PPC64

	select PPC_HAS_HASH_64K

	help

	  This option changes the kernel logical page size to 64k. On machines

	  without processor support for 64k pages, the kernel will simulate

arch/powerpc/mm/hash_low_64.S

+4 −1
Original line number Diff line number Diff line
@@ -615,6 +615,9 @@ htab_pte_insert_failure: 
	li	r3,-1

	b	htab_bail



#endif /* CONFIG_PPC_64K_PAGES */



#ifdef CONFIG_PPC_HAS_HASH_64K



/*****************************************************************************

 *                                                                           *
@@ -870,7 +873,7 @@ ht64_pte_insert_failure: 
	b	ht64_bail





#endif /* CONFIG_PPC_64K_PAGES */

#endif /* CONFIG_PPC_HAS_HASH_64K */





/*****************************************************************************

arch/powerpc/mm/hash_utils_64.c

+27 −12
Original line number Diff line number Diff line
@@ -420,7 +420,7 @@ static void __init htab_finish_init(void) 
	extern unsigned int *htab_call_hpte_remove;

	extern unsigned int *htab_call_hpte_updatepp;



#ifdef CONFIG_PPC_64K_PAGES

#ifdef CONFIG_PPC_HAS_HASH_64K

	extern unsigned int *ht64_call_hpte_insert1;

	extern unsigned int *ht64_call_hpte_insert2;

	extern unsigned int *ht64_call_hpte_remove;
@@ -648,7 +648,11 @@ int hash_page(unsigned long ea, unsigned long access, unsigned long trap) 
			return 1;

		}

		vsid = get_vsid(mm->context.id, ea);

#ifdef CONFIG_PPC_MM_SLICES

		psize = get_slice_psize(mm, ea);

#else

		psize = mm->context.user_psize;

#endif

		break;

	case VMALLOC_REGION_ID:

		mm = &init_mm;
@@ -678,13 +682,21 @@ int hash_page(unsigned long ea, unsigned long access, unsigned long trap) 


#ifdef CONFIG_HUGETLB_PAGE

	/* Handle hugepage regions */

	if (HPAGE_SHIFT &&

	    unlikely(get_slice_psize(mm, ea) == mmu_huge_psize)) {

	if (HPAGE_SHIFT && psize == mmu_huge_psize) {

		DBG_LOW(" -> huge page !\n");

		return hash_huge_page(mm, access, ea, vsid, local, trap);

	}

#endif /* CONFIG_HUGETLB_PAGE */



#ifndef CONFIG_PPC_64K_PAGES

	/* If we use 4K pages and our psize is not 4K, then we are hitting

	 * a special driver mapping, we need to align the address before

	 * we fetch the PTE

	 */

	if (psize != MMU_PAGE_4K)

		ea &= ~((1ul << mmu_psize_defs[psize].shift) - 1);

#endif /* CONFIG_PPC_64K_PAGES */



	/* Get PTE and page size from page tables */

	ptep = find_linux_pte(pgdir, ea);

	if (ptep == NULL || !pte_present(*ptep)) {
@@ -707,9 +719,7 @@ int hash_page(unsigned long ea, unsigned long access, unsigned long trap) 
	}



	/* Do actual hashing */

#ifndef CONFIG_PPC_64K_PAGES

	rc = __hash_page_4K(ea, access, vsid, ptep, trap, local);

#else

#ifdef CONFIG_PPC_64K_PAGES

	/* If _PAGE_4K_PFN is set, make sure this is a 4k segment */

	if (pte_val(*ptep) & _PAGE_4K_PFN) {

		demote_segment_4k(mm, ea);
@@ -751,12 +761,14 @@ int hash_page(unsigned long ea, unsigned long access, unsigned long trap) 
			mmu_psize_defs[mmu_vmalloc_psize].sllp;

		slb_flush_and_rebolt();

	}

#endif /* CONFIG_PPC_64K_PAGES */



#ifdef CONFIG_PPC_HAS_HASH_64K

	if (psize == MMU_PAGE_64K)

		rc = __hash_page_64K(ea, access, vsid, ptep, trap, local);

	else

#endif /* CONFIG_PPC_HAS_HASH_64K */

		rc = __hash_page_4K(ea, access, vsid, ptep, trap, local);

#endif /* CONFIG_PPC_64K_PAGES */



#ifndef CONFIG_PPC_64K_PAGES

	DBG_LOW(" o-pte: %016lx\n", pte_val(*ptep));
@@ -812,19 +824,22 @@ void hash_preload(struct mm_struct *mm, unsigned long ea, 
	/* Get VSID */

	vsid = get_vsid(mm->context.id, ea);



	/* Hash it in */

	/* Hash doesn't like irqs */

	local_irq_save(flags);



	/* Is that local to this CPU ? */

	mask = cpumask_of_cpu(smp_processor_id());

	if (cpus_equal(mm->cpu_vm_mask, mask))

		local = 1;

#ifndef CONFIG_PPC_64K_PAGES

	__hash_page_4K(ea, access, vsid, ptep, trap, local);

#else



	/* Hash it in */

#ifdef CONFIG_PPC_HAS_HASH_64K

	if (mm->context.user_psize == MMU_PAGE_64K)

		__hash_page_64K(ea, access, vsid, ptep, trap, local);

	else

		__hash_page_4K(ea, access, vsid, ptep, trap, local);

#endif /* CONFIG_PPC_64K_PAGES */

		__hash_page_4K(ea, access, vsid, ptep, trap, local);



	local_irq_restore(flags);

}

arch/powerpc/mm/tlb_64.c

+9 −3
Original line number Diff line number Diff line
@@ -143,16 +143,22 @@ void hpte_need_flush(struct mm_struct *mm, unsigned long addr, 
	 */

	addr &= PAGE_MASK;



	/* Get page size (maybe move back to caller) */

	/* Get page size (maybe move back to caller).

	 *

	 * NOTE: when using special 64K mappings in 4K environment like

	 * for SPEs, we obtain the page size from the slice, which thus

	 * must still exist (and thus the VMA not reused) at the time

	 * of this call

	 */

	if (huge) {

#ifdef CONFIG_HUGETLB_PAGE

		psize = mmu_huge_psize;

#else

		BUG();

		psize = pte_pagesize_index(pte); /* shutup gcc */

		psize = pte_pagesize_index(mm, addr, pte); /* shutup gcc */

#endif

	} else

		psize = pte_pagesize_index(pte);

		psize = pte_pagesize_index(mm, addr, pte);



	/* Build full vaddr */

	if (!is_kernel_addr(addr)) {

include/asm-powerpc/pgtable-4k.h

+5 −1
Original line number Diff line number Diff line
@@ -80,7 +80,11 @@ 


#define pte_iterate_hashed_end() } while(0)



#define pte_pagesize_index(pte)	MMU_PAGE_4K

#ifdef CONFIG_PPC_HAS_HASH_64K

#define pte_pagesize_index(mm, addr, pte)	get_slice_psize(mm, addr)

#else

#define pte_pagesize_index(mm, addr, pte)	MMU_PAGE_4K

#endif



/*

 * 4-level page tables related bits