summaryrefslogtreecommitdiff
path: root/arch/mips/mm/pgtable-64.c
diff options
context:
space:
mode:
authorAlex Belits <alex.belits@cavium.com>2017-02-17 04:27:34 +0300
committerRalf Baechle <ralf@linux-mips.org>2017-04-10 12:56:06 +0300
commit3377e227af441aff710726437adc20efc359fd9c (patch)
treed05610ba07eca74f783b42fbbd5110b7876d8c9b /arch/mips/mm/pgtable-64.c
parentdfa32261fa0ed1821c7d5dbb9e93eddfe311a0d9 (diff)
downloadlinux-3377e227af441aff710726437adc20efc359fd9c.tar.xz
MIPS: Add 48-bit VA space (and 4-level page tables) for 4K pages.
Some users must have 4K pages while needing a 48-bit VA space size. The cleanest way do do this is to go to a 4-level page table for this case. Each page table level using order-0 pages adds 9 bits to the VA size (at 4K pages, so for four levels we get 9 * 4 + 12 == 48-bits. For the 4K page size case only we add support functions for the PUD level of the page table tree, also the TLB exception handlers get an extra level of tree walk. [david.daney@cavium.com: Forward port to v4.10.] [david.daney@cavium.com: Forward port to v4.11.] Signed-off-by: Alex Belits <alex.belits@cavium.com> Signed-off-by: David Daney <david.daney@cavium.com> Cc: James Hogan <james.hogan@imgtec.com> Cc: Alex Belits <alex.belits@cavium.com> Cc: linux-mips@linux-mips.org Cc: linux-kernel@vger.kernel.org Patchwork: https://patchwork.linux-mips.org/patch/15312/ Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Diffstat (limited to 'arch/mips/mm/pgtable-64.c')
-rw-r--r--arch/mips/mm/pgtable-64.c33
1 files changed, 30 insertions, 3 deletions
diff --git a/arch/mips/mm/pgtable-64.c b/arch/mips/mm/pgtable-64.c
index 0ae7b28b4db5..6fd6e96fdebb 100644
--- a/arch/mips/mm/pgtable-64.c
+++ b/arch/mips/mm/pgtable-64.c
@@ -19,10 +19,12 @@ void pgd_init(unsigned long page)
unsigned long *p, *end;
unsigned long entry;
-#ifdef __PAGETABLE_PMD_FOLDED
- entry = (unsigned long)invalid_pte_table;
-#else
+#if !defined(__PAGETABLE_PUD_FOLDED)
+ entry = (unsigned long)invalid_pud_table;
+#elif !defined(__PAGETABLE_PMD_FOLDED)
entry = (unsigned long)invalid_pmd_table;
+#else
+ entry = (unsigned long)invalid_pte_table;
#endif
p = (unsigned long *) page;
@@ -64,6 +66,28 @@ void pmd_init(unsigned long addr, unsigned long pagetable)
EXPORT_SYMBOL_GPL(pmd_init);
#endif
+#ifndef __PAGETABLE_PUD_FOLDED
+void pud_init(unsigned long addr, unsigned long pagetable)
+{
+ unsigned long *p, *end;
+
+ p = (unsigned long *)addr;
+ end = p + PTRS_PER_PUD;
+
+ do {
+ p[0] = pagetable;
+ p[1] = pagetable;
+ p[2] = pagetable;
+ p[3] = pagetable;
+ p[4] = pagetable;
+ p += 8;
+ p[-3] = pagetable;
+ p[-2] = pagetable;
+ p[-1] = pagetable;
+ } while (p != end);
+}
+#endif
+
pmd_t mk_pmd(struct page *page, pgprot_t prot)
{
pmd_t pmd;
@@ -87,6 +111,9 @@ void __init pagetable_init(void)
/* Initialize the entire pgd. */
pgd_init((unsigned long)swapper_pg_dir);
+#ifndef __PAGETABLE_PUD_FOLDED
+ pud_init((unsigned long)invalid_pud_table, (unsigned long)invalid_pmd_table);
+#endif
#ifndef __PAGETABLE_PMD_FOLDED
pmd_init((unsigned long)invalid_pmd_table, (unsigned long)invalid_pte_table);
#endif