s390/mm: add support for 2GB hugepages
This adds support for 2GB hugetlbfs pages on s390.
Reviewed-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Gerald Schaefer <gerald.schaefer@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
diff --git a/arch/s390/include/asm/hugetlb.h b/arch/s390/include/asm/hugetlb.h
index d9be7c0..4c7fac7 100644
--- a/arch/s390/include/asm/hugetlb.h
+++ b/arch/s390/include/asm/hugetlb.h
@@ -41,7 +41,10 @@
static inline void huge_pte_clear(struct mm_struct *mm, unsigned long addr,
pte_t *ptep)
{
- pte_val(*ptep) = _SEGMENT_ENTRY_EMPTY;
+ if ((pte_val(*ptep) & _REGION_ENTRY_TYPE_MASK) == _REGION_ENTRY_TYPE_R3)
+ pte_val(*ptep) = _REGION3_ENTRY_EMPTY;
+ else
+ pte_val(*ptep) = _SEGMENT_ENTRY_EMPTY;
}
static inline void huge_ptep_clear_flush(struct vm_area_struct *vma,
diff --git a/arch/s390/include/asm/page.h b/arch/s390/include/asm/page.h
index 42fd5fe..b2146c4 100644
--- a/arch/s390/include/asm/page.h
+++ b/arch/s390/include/asm/page.h
@@ -21,6 +21,7 @@
#define HPAGE_SIZE (1UL << HPAGE_SHIFT)
#define HPAGE_MASK (~(HPAGE_SIZE - 1))
#define HUGETLB_PAGE_ORDER (HPAGE_SHIFT - PAGE_SHIFT)
+#define HUGE_MAX_HSTATE 2
#define ARCH_HAS_SETCLEAR_HUGE_PTE
#define ARCH_HAS_HUGE_PTE_TYPE
diff --git a/arch/s390/include/asm/pgtable.h b/arch/s390/include/asm/pgtable.h
index 37e1aa9..ea1533e 100644
--- a/arch/s390/include/asm/pgtable.h
+++ b/arch/s390/include/asm/pgtable.h
@@ -306,6 +306,9 @@
#define _REGION3_ENTRY_SOFT_DIRTY 0x0000 /* SW region soft dirty bit */
#endif
+#define _REGION_ENTRY_BITS 0xfffffffffffff227UL
+#define _REGION_ENTRY_BITS_LARGE 0xffffffff8000fe27UL
+
/* Bits in the segment table entry */
#define _SEGMENT_ENTRY_BITS 0xfffffffffffffe33UL
#define _SEGMENT_ENTRY_BITS_LARGE 0xfffffffffff0ff33UL
@@ -573,7 +576,7 @@
{
if ((pud_val(pud) & _REGION_ENTRY_TYPE_MASK) < _REGION_ENTRY_TYPE_R3)
return 0;
- return (pud_val(pud) & _REGION_ENTRY_INVALID) != 0UL;
+ return pud_val(pud) == _REGION3_ENTRY_EMPTY;
}
static inline int pud_large(pud_t pud)
@@ -593,17 +596,25 @@
return (pud_val(pud) & origin_mask) >> PAGE_SHIFT;
}
+static inline int pmd_large(pmd_t pmd)
+{
+ return (pmd_val(pmd) & _SEGMENT_ENTRY_LARGE) != 0;
+}
+
+static inline int pmd_bad(pmd_t pmd)
+{
+ if (pmd_large(pmd))
+ return (pmd_val(pmd) & ~_SEGMENT_ENTRY_BITS_LARGE) != 0;
+ return (pmd_val(pmd) & ~_SEGMENT_ENTRY_BITS) != 0;
+}
+
static inline int pud_bad(pud_t pud)
{
- /*
- * With dynamic page table levels the pud can be a region table
- * entry or a segment table entry. Check for the bit that are
- * invalid for either table entry.
- */
- unsigned long mask =
- ~_SEGMENT_ENTRY_ORIGIN & ~_REGION_ENTRY_INVALID &
- ~_REGION_ENTRY_TYPE_MASK & ~_REGION_ENTRY_LENGTH;
- return (pud_val(pud) & mask) != 0;
+ if ((pud_val(pud) & _REGION_ENTRY_TYPE_MASK) < _REGION_ENTRY_TYPE_R3)
+ return pmd_bad(__pmd(pud_val(pud)));
+ if (pud_large(pud))
+ return (pud_val(pud) & ~_REGION_ENTRY_BITS_LARGE) != 0;
+ return (pud_val(pud) & ~_REGION_ENTRY_BITS) != 0;
}
static inline int pmd_present(pmd_t pmd)
@@ -616,11 +627,6 @@
return pmd_val(pmd) == _SEGMENT_ENTRY_INVALID;
}
-static inline int pmd_large(pmd_t pmd)
-{
- return (pmd_val(pmd) & _SEGMENT_ENTRY_LARGE) != 0;
-}
-
static inline unsigned long pmd_pfn(pmd_t pmd)
{
unsigned long origin_mask;
@@ -631,13 +637,6 @@
return (pmd_val(pmd) & origin_mask) >> PAGE_SHIFT;
}
-static inline int pmd_bad(pmd_t pmd)
-{
- if (pmd_large(pmd))
- return (pmd_val(pmd) & ~_SEGMENT_ENTRY_BITS_LARGE) != 0;
- return (pmd_val(pmd) & ~_SEGMENT_ENTRY_BITS) != 0;
-}
-
#define __HAVE_ARCH_PMD_WRITE
static inline int pmd_write(pmd_t pmd)
{
@@ -1081,6 +1080,7 @@
#define pte_page(x) pfn_to_page(pte_pfn(x))
#define pmd_page(pmd) pfn_to_page(pmd_pfn(pmd))
+#define pud_page(pud) pfn_to_page(pud_pfn(pud))
/* Find an entry in the lowest level page table.. */
#define pte_offset(pmd, addr) ((pte_t *) pmd_deref(*(pmd)) + pte_index(addr))
@@ -1238,6 +1238,19 @@
: "cc" );
}
+static inline void __pudp_idte(unsigned long address, pud_t *pudp)
+{
+ unsigned long r3o;
+
+ r3o = (unsigned long) pudp - pud_index(address) * sizeof(pud_t);
+ r3o |= _ASCE_TYPE_REGION3;
+ asm volatile(
+ " .insn rrf,0xb98e0000,%2,%3,0,0"
+ : "=m" (*pudp)
+ : "m" (*pudp), "a" (r3o), "a" ((address & PUD_MASK))
+ : "cc");
+}
+
static inline void __pmdp_idte_local(unsigned long address, pmd_t *pmdp)
{
unsigned long sto;
@@ -1250,8 +1263,22 @@
: "cc" );
}
+static inline void __pudp_idte_local(unsigned long address, pud_t *pudp)
+{
+ unsigned long r3o;
+
+ r3o = (unsigned long) pudp - pud_index(address) * sizeof(pud_t);
+ r3o |= _ASCE_TYPE_REGION3;
+ asm volatile(
+ " .insn rrf,0xb98e0000,%2,%3,0,1"
+ : "=m" (*pudp)
+ : "m" (*pudp), "a" (r3o), "a" ((address & PUD_MASK))
+ : "cc");
+}
+
pmd_t pmdp_xchg_direct(struct mm_struct *, unsigned long, pmd_t *, pmd_t);
pmd_t pmdp_xchg_lazy(struct mm_struct *, unsigned long, pmd_t *, pmd_t);
+pud_t pudp_xchg_direct(struct mm_struct *, unsigned long, pud_t *, pud_t);
#ifdef CONFIG_TRANSPARENT_HUGEPAGE
diff --git a/arch/s390/mm/gmap.c b/arch/s390/mm/gmap.c
index cace818..69466f6 100644
--- a/arch/s390/mm/gmap.c
+++ b/arch/s390/mm/gmap.c
@@ -430,6 +430,9 @@
VM_BUG_ON(pgd_none(*pgd));
pud = pud_offset(pgd, vmaddr);
VM_BUG_ON(pud_none(*pud));
+ /* large puds cannot yet be handled */
+ if (pud_large(*pud))
+ return -EFAULT;
pmd = pmd_offset(pud, vmaddr);
VM_BUG_ON(pmd_none(*pmd));
/* large pmds cannot yet be handled */
diff --git a/arch/s390/mm/gup.c b/arch/s390/mm/gup.c
index a8a6765..adb0c34 100644
--- a/arch/s390/mm/gup.c
+++ b/arch/s390/mm/gup.c
@@ -128,6 +128,44 @@
return 1;
}
+static int gup_huge_pud(pud_t *pudp, pud_t pud, unsigned long addr,
+ unsigned long end, int write, struct page **pages, int *nr)
+{
+ struct page *head, *page;
+ unsigned long mask;
+ int refs;
+
+ mask = (write ? _REGION_ENTRY_PROTECT : 0) | _REGION_ENTRY_INVALID;
+ if ((pud_val(pud) & mask) != 0)
+ return 0;
+ VM_BUG_ON(!pfn_valid(pud_pfn(pud)));
+
+ refs = 0;
+ head = pud_page(pud);
+ page = head + ((addr & ~PUD_MASK) >> PAGE_SHIFT);
+ do {
+ VM_BUG_ON_PAGE(compound_head(page) != head, page);
+ pages[*nr] = page;
+ (*nr)++;
+ page++;
+ refs++;
+ } while (addr += PAGE_SIZE, addr != end);
+
+ if (!page_cache_add_speculative(head, refs)) {
+ *nr -= refs;
+ return 0;
+ }
+
+ if (unlikely(pud_val(pud) != pud_val(*pudp))) {
+ *nr -= refs;
+ while (refs--)
+ put_page(head);
+ return 0;
+ }
+
+ return 1;
+}
+
static inline int gup_pud_range(pgd_t *pgdp, pgd_t pgd, unsigned long addr,
unsigned long end, int write, struct page **pages, int *nr)
{
@@ -144,7 +182,12 @@
next = pud_addr_end(addr, end);
if (pud_none(pud))
return 0;
- if (!gup_pmd_range(pudp, pud, addr, next, write, pages, nr))
+ if (unlikely(pud_large(pud))) {
+ if (!gup_huge_pud(pudp, pud, addr, next, write, pages,
+ nr))
+ return 0;
+ } else if (!gup_pmd_range(pudp, pud, addr, next, write, pages,
+ nr))
return 0;
} while (pudp++, addr = next, addr != end);
diff --git a/arch/s390/mm/hugetlbpage.c b/arch/s390/mm/hugetlbpage.c
index 1b5e898..e19d853 100644
--- a/arch/s390/mm/hugetlbpage.c
+++ b/arch/s390/mm/hugetlbpage.c
@@ -1,19 +1,22 @@
/*
* IBM System z Huge TLB Page Support for Kernel.
*
- * Copyright IBM Corp. 2007
+ * Copyright IBM Corp. 2007,2016
* Author(s): Gerald Schaefer <gerald.schaefer@de.ibm.com>
*/
+#define KMSG_COMPONENT "hugetlb"
+#define pr_fmt(fmt) KMSG_COMPONENT ": " fmt
+
#include <linux/mm.h>
#include <linux/hugetlb.h>
-static inline pmd_t __pte_to_pmd(pte_t pte)
+static inline unsigned long __pte_to_rste(pte_t pte)
{
- pmd_t pmd;
+ unsigned long rste;
/*
- * Convert encoding pte bits pmd bits
+ * Convert encoding pte bits pmd / pud bits
* lIR.uswrdy.p dy..R...I...wr
* empty 010.000000.0 -> 00..0...1...00
* prot-none, clean, old 111.000000.1 -> 00..1...1...00
@@ -33,25 +36,31 @@
* u unused, l large
*/
if (pte_present(pte)) {
- pmd_val(pmd) = pte_val(pte) & PAGE_MASK;
- pmd_val(pmd) |= (pte_val(pte) & _PAGE_READ) >> 4;
- pmd_val(pmd) |= (pte_val(pte) & _PAGE_WRITE) >> 4;
- pmd_val(pmd) |= (pte_val(pte) & _PAGE_INVALID) >> 5;
- pmd_val(pmd) |= (pte_val(pte) & _PAGE_PROTECT);
- pmd_val(pmd) |= (pte_val(pte) & _PAGE_DIRTY) << 10;
- pmd_val(pmd) |= (pte_val(pte) & _PAGE_YOUNG) << 10;
- pmd_val(pmd) |= (pte_val(pte) & _PAGE_SOFT_DIRTY) << 13;
+ rste = pte_val(pte) & PAGE_MASK;
+ rste |= (pte_val(pte) & _PAGE_READ) >> 4;
+ rste |= (pte_val(pte) & _PAGE_WRITE) >> 4;
+ rste |= (pte_val(pte) & _PAGE_INVALID) >> 5;
+ rste |= (pte_val(pte) & _PAGE_PROTECT);
+ rste |= (pte_val(pte) & _PAGE_DIRTY) << 10;
+ rste |= (pte_val(pte) & _PAGE_YOUNG) << 10;
+ rste |= (pte_val(pte) & _PAGE_SOFT_DIRTY) << 13;
} else
- pmd_val(pmd) = _SEGMENT_ENTRY_INVALID;
- return pmd;
+ rste = _SEGMENT_ENTRY_INVALID;
+ return rste;
}
-static inline pte_t __pmd_to_pte(pmd_t pmd)
+static inline pte_t __rste_to_pte(unsigned long rste)
{
+ int present;
pte_t pte;
+ if ((rste & _REGION_ENTRY_TYPE_MASK) == _REGION_ENTRY_TYPE_R3)
+ present = pud_present(__pud(rste));
+ else
+ present = pmd_present(__pmd(rste));
+
/*
- * Convert encoding pmd bits pte bits
+ * Convert encoding pmd / pud bits pte bits
* dy..R...I...wr lIR.uswrdy.p
* empty 00..0...1...00 -> 010.000000.0
* prot-none, clean, old 00..1...1...00 -> 111.000000.1
@@ -70,16 +79,16 @@
* SW-bits: p present, y young, d dirty, r read, w write, s special,
* u unused, l large
*/
- if (pmd_present(pmd)) {
- pte_val(pte) = pmd_val(pmd) & _SEGMENT_ENTRY_ORIGIN_LARGE;
+ if (present) {
+ pte_val(pte) = rste & _SEGMENT_ENTRY_ORIGIN_LARGE;
pte_val(pte) |= _PAGE_LARGE | _PAGE_PRESENT;
- pte_val(pte) |= (pmd_val(pmd) & _SEGMENT_ENTRY_READ) << 4;
- pte_val(pte) |= (pmd_val(pmd) & _SEGMENT_ENTRY_WRITE) << 4;
- pte_val(pte) |= (pmd_val(pmd) & _SEGMENT_ENTRY_INVALID) << 5;
- pte_val(pte) |= (pmd_val(pmd) & _SEGMENT_ENTRY_PROTECT);
- pte_val(pte) |= (pmd_val(pmd) & _SEGMENT_ENTRY_DIRTY) >> 10;
- pte_val(pte) |= (pmd_val(pmd) & _SEGMENT_ENTRY_YOUNG) >> 10;
- pte_val(pte) |= (pmd_val(pmd) & _SEGMENT_ENTRY_SOFT_DIRTY) >> 13;
+ pte_val(pte) |= (rste & _SEGMENT_ENTRY_READ) << 4;
+ pte_val(pte) |= (rste & _SEGMENT_ENTRY_WRITE) << 4;
+ pte_val(pte) |= (rste & _SEGMENT_ENTRY_INVALID) << 5;
+ pte_val(pte) |= (rste & _SEGMENT_ENTRY_PROTECT);
+ pte_val(pte) |= (rste & _SEGMENT_ENTRY_DIRTY) >> 10;
+ pte_val(pte) |= (rste & _SEGMENT_ENTRY_YOUNG) >> 10;
+ pte_val(pte) |= (rste & _SEGMENT_ENTRY_SOFT_DIRTY) >> 13;
} else
pte_val(pte) = _PAGE_INVALID;
return pte;
@@ -88,27 +97,33 @@
void set_huge_pte_at(struct mm_struct *mm, unsigned long addr,
pte_t *ptep, pte_t pte)
{
- pmd_t pmd = __pte_to_pmd(pte);
+ unsigned long rste = __pte_to_rste(pte);
- pmd_val(pmd) |= _SEGMENT_ENTRY_LARGE;
- *(pmd_t *) ptep = pmd;
+ /* Set correct table type for 2G hugepages */
+ if ((pte_val(*ptep) & _REGION_ENTRY_TYPE_MASK) == _REGION_ENTRY_TYPE_R3)
+ rste |= _REGION_ENTRY_TYPE_R3 | _REGION3_ENTRY_LARGE;
+ else
+ rste |= _SEGMENT_ENTRY_LARGE;
+ pte_val(*ptep) = rste;
}
pte_t huge_ptep_get(pte_t *ptep)
{
- pmd_t pmd = *(pmd_t *) ptep;
-
- return __pmd_to_pte(pmd);
+ return __rste_to_pte(pte_val(*ptep));
}
pte_t huge_ptep_get_and_clear(struct mm_struct *mm,
unsigned long addr, pte_t *ptep)
{
+ pte_t pte = huge_ptep_get(ptep);
pmd_t *pmdp = (pmd_t *) ptep;
- pmd_t old;
+ pud_t *pudp = (pud_t *) ptep;
- old = pmdp_xchg_direct(mm, addr, pmdp, __pmd(_SEGMENT_ENTRY_EMPTY));
- return __pmd_to_pte(old);
+ if ((pte_val(*ptep) & _REGION_ENTRY_TYPE_MASK) == _REGION_ENTRY_TYPE_R3)
+ pudp_xchg_direct(mm, addr, pudp, __pud(_REGION3_ENTRY_EMPTY));
+ else
+ pmdp_xchg_direct(mm, addr, pmdp, __pmd(_SEGMENT_ENTRY_EMPTY));
+ return pte;
}
pte_t *huge_pte_alloc(struct mm_struct *mm,
@@ -120,8 +135,12 @@
pgdp = pgd_offset(mm, addr);
pudp = pud_alloc(mm, pgdp, addr);
- if (pudp)
- pmdp = pmd_alloc(mm, pudp, addr);
+ if (pudp) {
+ if (sz == PUD_SIZE)
+ return (pte_t *) pudp;
+ else if (sz == PMD_SIZE)
+ pmdp = pmd_alloc(mm, pudp, addr);
+ }
return (pte_t *) pmdp;
}
@@ -134,8 +153,11 @@
pgdp = pgd_offset(mm, addr);
if (pgd_present(*pgdp)) {
pudp = pud_offset(pgdp, addr);
- if (pud_present(*pudp))
+ if (pud_present(*pudp)) {
+ if (pud_large(*pudp))
+ return (pte_t *) pudp;
pmdp = pmd_offset(pudp, addr);
+ }
}
return (pte_t *) pmdp;
}
@@ -147,5 +169,34 @@
int pud_huge(pud_t pud)
{
- return 0;
+ return pud_large(pud);
}
+
+struct page *
+follow_huge_pud(struct mm_struct *mm, unsigned long address,
+ pud_t *pud, int flags)
+{
+ if (flags & FOLL_GET)
+ return NULL;
+
+ return pud_page(*pud) + ((address & ~PUD_MASK) >> PAGE_SHIFT);
+}
+
+static __init int setup_hugepagesz(char *opt)
+{
+ unsigned long size;
+ char *string = opt;
+
+ size = memparse(opt, &opt);
+ if (MACHINE_HAS_EDAT1 && size == PMD_SIZE) {
+ hugetlb_add_hstate(PMD_SHIFT - PAGE_SHIFT);
+ } else if (MACHINE_HAS_EDAT2 && size == PUD_SIZE) {
+ hugetlb_add_hstate(PUD_SHIFT - PAGE_SHIFT);
+ } else {
+ pr_err("hugepagesz= specifies an unsupported page size %s\n",
+ string);
+ return 0;
+ }
+ return 1;
+}
+__setup("hugepagesz=", setup_hugepagesz);
diff --git a/arch/s390/mm/pgtable.c b/arch/s390/mm/pgtable.c
index 74f8f2a..b98d1a1 100644
--- a/arch/s390/mm/pgtable.c
+++ b/arch/s390/mm/pgtable.c
@@ -352,6 +352,45 @@
}
EXPORT_SYMBOL(pmdp_xchg_lazy);
+static inline pud_t pudp_flush_direct(struct mm_struct *mm,
+ unsigned long addr, pud_t *pudp)
+{
+ pud_t old;
+
+ old = *pudp;
+ if (pud_val(old) & _REGION_ENTRY_INVALID)
+ return old;
+ if (!MACHINE_HAS_IDTE) {
+ /*
+ * Invalid bit position is the same for pmd and pud, so we can
+ * re-use _pmd_csp() here
+ */
+ __pmdp_csp((pmd_t *) pudp);
+ return old;
+ }
+ atomic_inc(&mm->context.flush_count);
+ if (MACHINE_HAS_TLB_LC &&
+ cpumask_equal(mm_cpumask(mm), cpumask_of(smp_processor_id())))
+ __pudp_idte_local(addr, pudp);
+ else
+ __pudp_idte(addr, pudp);
+ atomic_dec(&mm->context.flush_count);
+ return old;
+}
+
+pud_t pudp_xchg_direct(struct mm_struct *mm, unsigned long addr,
+ pud_t *pudp, pud_t new)
+{
+ pud_t old;
+
+ preempt_disable();
+ old = pudp_flush_direct(mm, addr, pudp);
+ *pudp = new;
+ preempt_enable();
+ return old;
+}
+EXPORT_SYMBOL(pudp_xchg_direct);
+
#ifdef CONFIG_TRANSPARENT_HUGEPAGE
void pgtable_trans_huge_deposit(struct mm_struct *mm, pmd_t *pmdp,
pgtable_t pgtable)
diff --git a/mm/hugetlb.c b/mm/hugetlb.c
index 388c2bb..7f0fa87 100644
--- a/mm/hugetlb.c
+++ b/mm/hugetlb.c
@@ -1022,7 +1022,9 @@
((node = hstate_next_node_to_free(hs, mask)) || 1); \
nr_nodes--)
-#if defined(CONFIG_X86_64) && ((defined(CONFIG_MEMORY_ISOLATION) && defined(CONFIG_COMPACTION)) || defined(CONFIG_CMA))
+#if (defined(CONFIG_X86_64) || defined(CONFIG_S390)) && \
+ ((defined(CONFIG_MEMORY_ISOLATION) && defined(CONFIG_COMPACTION)) || \
+ defined(CONFIG_CMA))
static void destroy_compound_gigantic_page(struct page *page,
unsigned int order)
{