powerpc: define support for 16G hugepages
The huge page size is defined for 16G pages. If a hugepagesz of 16G is
specified at boot-time then it becomes the huge page size instead of the
default 16M.
The change in pgtable-64K.h is to the macro pte_iterate_hashed_subpages to
make the increment to va (the 1 being shifted) be a long so that it is not
shifted to 0. Otherwise it would create an infinite loop when the shift
value is for a 16G page (when base page size is 64K).
Signed-off-by: Jon Tollefson <kniht@linux.vnet.ibm.com>
Signed-off-by: Nick Piggin <npiggin@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/arch/powerpc/mm/hugetlbpage.c b/arch/powerpc/mm/hugetlbpage.c
index e2a650a..19b1a9c 100644
--- a/arch/powerpc/mm/hugetlbpage.c
+++ b/arch/powerpc/mm/hugetlbpage.c
@@ -24,8 +24,9 @@
#include <asm/cputable.h>
#include <asm/spu.h>
-#define HPAGE_SHIFT_64K 16
-#define HPAGE_SHIFT_16M 24
+#define PAGE_SHIFT_64K 16
+#define PAGE_SHIFT_16M 24
+#define PAGE_SHIFT_16G 34
#define NUM_LOW_AREAS (0x100000000UL >> SID_SHIFT)
#define NUM_HIGH_AREAS (PGTABLE_RANGE >> HTLB_AREA_SHIFT)
@@ -95,7 +96,7 @@
static inline
pmd_t *hpmd_offset(pud_t *pud, unsigned long addr)
{
- if (HPAGE_SHIFT == HPAGE_SHIFT_64K)
+ if (HPAGE_SHIFT == PAGE_SHIFT_64K)
return pmd_offset(pud, addr);
else
return (pmd_t *) pud;
@@ -103,7 +104,7 @@
static inline
pmd_t *hpmd_alloc(struct mm_struct *mm, pud_t *pud, unsigned long addr)
{
- if (HPAGE_SHIFT == HPAGE_SHIFT_64K)
+ if (HPAGE_SHIFT == PAGE_SHIFT_64K)
return pmd_alloc(mm, pud, addr);
else
return (pmd_t *) pud;
@@ -260,7 +261,7 @@
continue;
hugetlb_free_pmd_range(tlb, pud, addr, next, floor, ceiling);
#else
- if (HPAGE_SHIFT == HPAGE_SHIFT_64K) {
+ if (HPAGE_SHIFT == PAGE_SHIFT_64K) {
if (pud_none_or_clear_bad(pud))
continue;
hugetlb_free_pmd_range(tlb, pud, addr, next, floor, ceiling);
@@ -592,20 +593,40 @@
{
/* Check that it is a page size supported by the hardware and
* that it fits within pagetable limits. */
- if (mmu_psize_defs[psize].shift && mmu_psize_defs[psize].shift < SID_SHIFT &&
+ if (mmu_psize_defs[psize].shift &&
+ mmu_psize_defs[psize].shift < SID_SHIFT_1T &&
(mmu_psize_defs[psize].shift > MIN_HUGEPTE_SHIFT ||
- mmu_psize_defs[psize].shift == HPAGE_SHIFT_64K)) {
+ mmu_psize_defs[psize].shift == PAGE_SHIFT_64K ||
+ mmu_psize_defs[psize].shift == PAGE_SHIFT_16G)) {
+ /* Return if huge page size is the same as the
+ * base page size. */
+ if (mmu_psize_defs[psize].shift == PAGE_SHIFT)
+ return;
+
HPAGE_SHIFT = mmu_psize_defs[psize].shift;
mmu_huge_psize = psize;
-#ifdef CONFIG_PPC_64K_PAGES
- hugepte_shift = (PMD_SHIFT-HPAGE_SHIFT);
-#else
- if (HPAGE_SHIFT == HPAGE_SHIFT_64K)
- hugepte_shift = (PMD_SHIFT-HPAGE_SHIFT);
- else
- hugepte_shift = (PUD_SHIFT-HPAGE_SHIFT);
-#endif
+ switch (HPAGE_SHIFT) {
+ case PAGE_SHIFT_64K:
+ /* We only allow 64k hpages with 4k base page,
+ * which was checked above, and always put them
+ * at the PMD */
+ hugepte_shift = PMD_SHIFT;
+ break;
+ case PAGE_SHIFT_16M:
+ /* 16M pages can be at two different levels
+ * of pagestables based on base page size */
+ if (PAGE_SHIFT == PAGE_SHIFT_64K)
+ hugepte_shift = PMD_SHIFT;
+ else /* 4k base page */
+ hugepte_shift = PUD_SHIFT;
+ break;
+ case PAGE_SHIFT_16G:
+ /* 16G pages are always at PGD level */
+ hugepte_shift = PGDIR_SHIFT;
+ break;
+ }
+ hugepte_shift -= HPAGE_SHIFT;
} else
HPAGE_SHIFT = 0;
}
@@ -621,17 +642,22 @@
shift = __ffs(size);
switch (shift) {
#ifndef CONFIG_PPC_64K_PAGES
- case HPAGE_SHIFT_64K:
+ case PAGE_SHIFT_64K:
mmu_psize = MMU_PAGE_64K;
break;
#endif
- case HPAGE_SHIFT_16M:
+ case PAGE_SHIFT_16M:
mmu_psize = MMU_PAGE_16M;
break;
+ case PAGE_SHIFT_16G:
+ mmu_psize = MMU_PAGE_16G;
+ break;
}
- if (mmu_psize >=0 && mmu_psize_defs[mmu_psize].shift)
+ if (mmu_psize >= 0 && mmu_psize_defs[mmu_psize].shift) {
set_huge_psize(mmu_psize);
+ hugetlb_add_hstate(shift - PAGE_SHIFT);
+ }
else
printk(KERN_WARNING "Invalid huge page size specified(%llu)\n", size);