Commit 18da2369 authored by Heiko Carstens's avatar Heiko Carstens Committed by Martin Schwidefsky
Browse files

s390/mm,vmem: use 2GB frames for identity mapping 



Use 2GB frames for indentity mapping if EDAT2 is
available to reduce TLB pressure.

Signed-off-by: default avatarHeiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: default avatarMartin Schwidefsky <schwidefsky@de.ibm.com>
parent 26d29d06

arch/s390/include/asm/pgtable.h

+10 −0
Original line number Diff line number Diff line
@@ -345,6 +345,8 @@ extern unsigned long MODULES_END; 
#define _REGION3_ENTRY		(_REGION_ENTRY_TYPE_R3 | _REGION_ENTRY_LENGTH)

#define _REGION3_ENTRY_EMPTY	(_REGION_ENTRY_TYPE_R3 | _REGION_ENTRY_INV)



#define _REGION3_ENTRY_LARGE	0x400	/* RTTE-format control, large page  */



/* Bits in the segment table entry */

#define _SEGMENT_ENTRY_ORIGIN	~0x7ffUL/* segment table origin		    */

#define _SEGMENT_ENTRY_RO	0x200	/* page protection bit		    */
@@ -444,6 +446,7 @@ static inline int pgd_bad(pgd_t pgd) { return 0; } 


static inline int pud_present(pud_t pud) { return 1; }

static inline int pud_none(pud_t pud)	 { return 0; }

static inline int pud_large(pud_t pud)	 { return 0; }

static inline int pud_bad(pud_t pud)	 { return 0; }



#else /* CONFIG_64BIT */
@@ -489,6 +492,13 @@ static inline int pud_none(pud_t pud) 
	return (pud_val(pud) & _REGION_ENTRY_INV) != 0UL;

}



static inline int pud_large(pud_t pud)

{

	if ((pud_val(pud) & _REGION_ENTRY_TYPE_MASK) != _REGION_ENTRY_TYPE_R3)

		return 0;

	return !!(pud_val(pud) & _REGION3_ENTRY_LARGE);

}



static inline int pud_bad(pud_t pud)

{

	/*

arch/s390/mm/dump_pagetables.c

+6 −1
Original line number Diff line number Diff line
@@ -150,6 +150,7 @@ static void walk_pmd_level(struct seq_file *m, struct pg_state *st, 
static void walk_pud_level(struct seq_file *m, struct pg_state *st,

			   pgd_t *pgd, unsigned long addr)

{

	unsigned int prot;

	pud_t *pud;

	int i;
@@ -157,6 +158,10 @@ static void walk_pud_level(struct seq_file *m, struct pg_state *st, 
		st->current_address = addr;

		pud = pud_offset(pgd, addr);

		if (!pud_none(*pud))

			if (pud_large(*pud)) {

				prot = pud_val(*pud) & _PAGE_RO;

				note_page(m, st, prot, 2);

			} else

				walk_pmd_level(m, st, pud, addr);

		else

			note_page(m, st, _PAGE_INVALID, 2);

arch/s390/mm/pageattr.c

+1 −1
Original line number Diff line number Diff line
@@ -19,7 +19,7 @@ static pte_t *walk_page_table(unsigned long addr) 
	if (pgd_none(*pgdp))

		return NULL;

	pudp = pud_offset(pgdp, addr);

	if (pud_none(*pudp))

	if (pud_none(*pudp) || pud_large(*pudp))

		return NULL;

	pmdp = pmd_offset(pudp, addr);

	if (pmd_none(*pmdp) || pmd_large(*pmdp))

arch/s390/mm/vmem.c

+16 −4
Original line number Diff line number Diff line
@@ -89,6 +89,7 @@ static int vmem_add_mem(unsigned long start, unsigned long size, int ro) 
	int ret = -ENOMEM;



	while (address < end) {

		pte = mk_pte_phys(address, __pgprot(ro ? _PAGE_RO : 0));

		pg_dir = pgd_offset_k(address);

		if (pgd_none(*pg_dir)) {

			pu_dir = vmem_pud_alloc();
@@ -96,18 +97,24 @@ static int vmem_add_mem(unsigned long start, unsigned long size, int ro) 
				goto out;

			pgd_populate(&init_mm, pg_dir, pu_dir);

		}



		pu_dir = pud_offset(pg_dir, address);

#if defined(CONFIG_64BIT) && !defined(CONFIG_DEBUG_PAGEALLOC)

		if (MACHINE_HAS_EDAT2 && pud_none(*pu_dir) && address &&

		    !(address & ~PUD_MASK) && (address + PUD_SIZE <= end)) {

			pte_val(pte) |= _REGION3_ENTRY_LARGE;

			pte_val(pte) |= _REGION_ENTRY_TYPE_R3;

			pud_val(*pu_dir) = pte_val(pte);

			address += PUD_SIZE;

			continue;

		}

#endif

		if (pud_none(*pu_dir)) {

			pm_dir = vmem_pmd_alloc();

			if (!pm_dir)

				goto out;

			pud_populate(&init_mm, pu_dir, pm_dir);

		}



		pte = mk_pte_phys(address, __pgprot(ro ? _PAGE_RO : 0));

		pm_dir = pmd_offset(pu_dir, address);



#if defined(CONFIG_64BIT) && !defined(CONFIG_DEBUG_PAGEALLOC)

		if (MACHINE_HAS_EDAT1 && pmd_none(*pm_dir) && address &&

		    !(address & ~PMD_MASK) && (address + PMD_SIZE <= end)) {
@@ -160,6 +167,11 @@ static void vmem_remove_range(unsigned long start, unsigned long size) 
			address += PUD_SIZE;

			continue;

		}

		if (pud_large(*pu_dir)) {

			pud_clear(pu_dir);

			address += PUD_SIZE;

			continue;

		}

		pm_dir = pmd_offset(pu_dir, address);

		if (pmd_none(*pm_dir)) {

			address += PMD_SIZE;