summaryrefslogtreecommitdiff
path: root/arch/powerpc/mm/pgtable-book3s64.c
diff options
context:
space:
mode:
authorAneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>2016-04-29 23:26:29 +1000
committerMichael Ellerman <mpe@ellerman.id.au>2016-05-11 21:53:57 +1000
commit3df33f12be2f6fa88dff12564ab1d069482e3224 (patch)
tree70a1a974df6f748741a5768a71c305a370812537 /arch/powerpc/mm/pgtable-book3s64.c
parent6a1ea36260f69f1aea85bbf8afcd6a8c193485b9 (diff)
downloadlinux-3df33f12be2f6fa88dff12564ab1d069482e3224.tar.gz
powerpc/mm/thp: Abstraction for THP functions
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Diffstat (limited to 'arch/powerpc/mm/pgtable-book3s64.c')
-rw-r--r--arch/powerpc/mm/pgtable-book3s64.c118
1 files changed, 118 insertions, 0 deletions
diff --git a/arch/powerpc/mm/pgtable-book3s64.c b/arch/powerpc/mm/pgtable-book3s64.c
new file mode 100644
index 000000000000..d566a250164d
--- /dev/null
+++ b/arch/powerpc/mm/pgtable-book3s64.c
@@ -0,0 +1,118 @@
+/*
+ * Copyright 2015-2016, Aneesh Kumar K.V, IBM Corporation.
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version
+ * 2 of the License, or (at your option) any later version.
+ */
+
+#include <linux/sched.h>
+#include <asm/pgalloc.h>
+#include <asm/tlb.h>
+
+#include "mmu_decl.h"
+#include <trace/events/thp.h>
+
+#ifdef CONFIG_TRANSPARENT_HUGEPAGE
+/*
+ * This is called when relaxing access to a hugepage. It's also called in the page
+ * fault path when we don't hit any of the major fault cases, ie, a minor
+ * update of _PAGE_ACCESSED, _PAGE_DIRTY, etc... The generic code will have
+ * handled those two for us, we additionally deal with missing execute
+ * permission here on some processors
+ */
+int pmdp_set_access_flags(struct vm_area_struct *vma, unsigned long address,
+ pmd_t *pmdp, pmd_t entry, int dirty)
+{
+ int changed;
+#ifdef CONFIG_DEBUG_VM
+ WARN_ON(!pmd_trans_huge(*pmdp));
+ assert_spin_locked(&vma->vm_mm->page_table_lock);
+#endif
+ changed = !pmd_same(*(pmdp), entry);
+ if (changed) {
+ __ptep_set_access_flags(pmdp_ptep(pmdp), pmd_pte(entry));
+ /*
+ * Since we are not supporting SW TLB systems, we don't
+ * have any thing similar to flush_tlb_page_nohash()
+ */
+ }
+ return changed;
+}
+
+int pmdp_test_and_clear_young(struct vm_area_struct *vma,
+ unsigned long address, pmd_t *pmdp)
+{
+ return __pmdp_test_and_clear_young(vma->vm_mm, address, pmdp);
+}
+/*
+ * set a new huge pmd. We should not be called for updating
+ * an existing pmd entry. That should go via pmd_hugepage_update.
+ */
+void set_pmd_at(struct mm_struct *mm, unsigned long addr,
+ pmd_t *pmdp, pmd_t pmd)
+{
+#ifdef CONFIG_DEBUG_VM
+ WARN_ON(pte_present(pmd_pte(*pmdp)) && !pte_protnone(pmd_pte(*pmdp)));
+ assert_spin_locked(&mm->page_table_lock);
+ WARN_ON(!pmd_trans_huge(pmd));
+#endif
+ trace_hugepage_set_pmd(addr, pmd_val(pmd));
+ return set_pte_at(mm, addr, pmdp_ptep(pmdp), pmd_pte(pmd));
+}
+/*
+ * We use this to invalidate a pmdp entry before switching from a
+ * hugepte to regular pmd entry.
+ */
+void pmdp_invalidate(struct vm_area_struct *vma, unsigned long address,
+ pmd_t *pmdp)
+{
+ pmd_hugepage_update(vma->vm_mm, address, pmdp, _PAGE_PRESENT, 0);
+
+ /*
+ * This ensures that generic code that rely on IRQ disabling
+ * to prevent a parallel THP split work as expected.
+ */
+ kick_all_cpus_sync();
+}
+
+static pmd_t pmd_set_protbits(pmd_t pmd, pgprot_t pgprot)
+{
+ return __pmd(pmd_val(pmd) | pgprot_val(pgprot));
+}
+
+pmd_t pfn_pmd(unsigned long pfn, pgprot_t pgprot)
+{
+ unsigned long pmdv;
+
+ pmdv = (pfn << PAGE_SHIFT) & PTE_RPN_MASK;
+ return pmd_set_protbits(__pmd(pmdv), pgprot);
+}
+
+pmd_t mk_pmd(struct page *page, pgprot_t pgprot)
+{
+ return pfn_pmd(page_to_pfn(page), pgprot);
+}
+
+pmd_t pmd_modify(pmd_t pmd, pgprot_t newprot)
+{
+ unsigned long pmdv;
+
+ pmdv = pmd_val(pmd);
+ pmdv &= _HPAGE_CHG_MASK;
+ return pmd_set_protbits(__pmd(pmdv), newprot);
+}
+
+/*
+ * This is called at the end of handling a user page fault, when the
+ * fault has been handled by updating a HUGE PMD entry in the linux page tables.
+ * We use it to preload an HPTE into the hash table corresponding to
+ * the updated linux HUGE PMD entry.
+ */
+void update_mmu_cache_pmd(struct vm_area_struct *vma, unsigned long addr,
+ pmd_t *pmd)
+{
+ return;
+}
+#endif /* CONFIG_TRANSPARENT_HUGEPAGE */