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-rw-r--r--arch/sparc/mm/tlb.c300
1 files changed, 300 insertions, 0 deletions
diff --git a/arch/sparc/mm/tlb.c b/arch/sparc/mm/tlb.c
new file mode 100644
index 000000000..9a7255475
--- /dev/null
+++ b/arch/sparc/mm/tlb.c
@@ -0,0 +1,300 @@
+// SPDX-License-Identifier: GPL-2.0
+/* arch/sparc64/mm/tlb.c
+ *
+ * Copyright (C) 2004 David S. Miller <davem@redhat.com>
+ */
+
+#include <linux/kernel.h>
+#include <linux/percpu.h>
+#include <linux/mm.h>
+#include <linux/swap.h>
+#include <linux/preempt.h>
+#include <linux/pagemap.h>
+
+#include <asm/tlbflush.h>
+#include <asm/cacheflush.h>
+#include <asm/mmu_context.h>
+#include <asm/tlb.h>
+
+/* Heavily inspired by the ppc64 code. */
+
+static DEFINE_PER_CPU(struct tlb_batch, tlb_batch);
+
+void flush_tlb_pending(void)
+{
+ struct tlb_batch *tb = &get_cpu_var(tlb_batch);
+ struct mm_struct *mm = tb->mm;
+
+ if (!tb->tlb_nr)
+ goto out;
+
+ flush_tsb_user(tb);
+
+ if (CTX_VALID(mm->context)) {
+ if (tb->tlb_nr == 1) {
+ global_flush_tlb_page(mm, tb->vaddrs[0]);
+ } else {
+#ifdef CONFIG_SMP
+ smp_flush_tlb_pending(tb->mm, tb->tlb_nr,
+ &tb->vaddrs[0]);
+#else
+ __flush_tlb_pending(CTX_HWBITS(tb->mm->context),
+ tb->tlb_nr, &tb->vaddrs[0]);
+#endif
+ }
+ }
+
+ tb->tlb_nr = 0;
+
+out:
+ put_cpu_var(tlb_batch);
+}
+
+void arch_enter_lazy_mmu_mode(void)
+{
+ struct tlb_batch *tb = this_cpu_ptr(&tlb_batch);
+
+ tb->active = 1;
+}
+
+void arch_leave_lazy_mmu_mode(void)
+{
+ struct tlb_batch *tb = this_cpu_ptr(&tlb_batch);
+
+ if (tb->tlb_nr)
+ flush_tlb_pending();
+ tb->active = 0;
+}
+
+static void tlb_batch_add_one(struct mm_struct *mm, unsigned long vaddr,
+ bool exec, unsigned int hugepage_shift)
+{
+ struct tlb_batch *tb = &get_cpu_var(tlb_batch);
+ unsigned long nr;
+
+ vaddr &= PAGE_MASK;
+ if (exec)
+ vaddr |= 0x1UL;
+
+ nr = tb->tlb_nr;
+
+ if (unlikely(nr != 0 && mm != tb->mm)) {
+ flush_tlb_pending();
+ nr = 0;
+ }
+
+ if (!tb->active) {
+ flush_tsb_user_page(mm, vaddr, hugepage_shift);
+ global_flush_tlb_page(mm, vaddr);
+ goto out;
+ }
+
+ if (nr == 0) {
+ tb->mm = mm;
+ tb->hugepage_shift = hugepage_shift;
+ }
+
+ if (tb->hugepage_shift != hugepage_shift) {
+ flush_tlb_pending();
+ tb->hugepage_shift = hugepage_shift;
+ nr = 0;
+ }
+
+ tb->vaddrs[nr] = vaddr;
+ tb->tlb_nr = ++nr;
+ if (nr >= TLB_BATCH_NR)
+ flush_tlb_pending();
+
+out:
+ put_cpu_var(tlb_batch);
+}
+
+void tlb_batch_add(struct mm_struct *mm, unsigned long vaddr,
+ pte_t *ptep, pte_t orig, int fullmm,
+ unsigned int hugepage_shift)
+{
+ if (tlb_type != hypervisor &&
+ pte_dirty(orig)) {
+ unsigned long paddr, pfn = pte_pfn(orig);
+ struct address_space *mapping;
+ struct page *page;
+
+ if (!pfn_valid(pfn))
+ goto no_cache_flush;
+
+ page = pfn_to_page(pfn);
+ if (PageReserved(page))
+ goto no_cache_flush;
+
+ /* A real file page? */
+ mapping = page_mapping_file(page);
+ if (!mapping)
+ goto no_cache_flush;
+
+ paddr = (unsigned long) page_address(page);
+ if ((paddr ^ vaddr) & (1 << 13))
+ flush_dcache_page_all(mm, page);
+ }
+
+no_cache_flush:
+ if (!fullmm)
+ tlb_batch_add_one(mm, vaddr, pte_exec(orig), hugepage_shift);
+}
+
+#ifdef CONFIG_TRANSPARENT_HUGEPAGE
+static void tlb_batch_pmd_scan(struct mm_struct *mm, unsigned long vaddr,
+ pmd_t pmd)
+{
+ unsigned long end;
+ pte_t *pte;
+
+ pte = pte_offset_map(&pmd, vaddr);
+ end = vaddr + HPAGE_SIZE;
+ while (vaddr < end) {
+ if (pte_val(*pte) & _PAGE_VALID) {
+ bool exec = pte_exec(*pte);
+
+ tlb_batch_add_one(mm, vaddr, exec, PAGE_SHIFT);
+ }
+ pte++;
+ vaddr += PAGE_SIZE;
+ }
+ pte_unmap(pte);
+}
+
+
+static void __set_pmd_acct(struct mm_struct *mm, unsigned long addr,
+ pmd_t orig, pmd_t pmd)
+{
+ if (mm == &init_mm)
+ return;
+
+ if ((pmd_val(pmd) ^ pmd_val(orig)) & _PAGE_PMD_HUGE) {
+ /*
+ * Note that this routine only sets pmds for THP pages.
+ * Hugetlb pages are handled elsewhere. We need to check
+ * for huge zero page. Huge zero pages are like hugetlb
+ * pages in that there is no RSS, but there is the need
+ * for TSB entries. So, huge zero page counts go into
+ * hugetlb_pte_count.
+ */
+ if (pmd_val(pmd) & _PAGE_PMD_HUGE) {
+ if (is_huge_zero_page(pmd_page(pmd)))
+ mm->context.hugetlb_pte_count++;
+ else
+ mm->context.thp_pte_count++;
+ } else {
+ if (is_huge_zero_page(pmd_page(orig)))
+ mm->context.hugetlb_pte_count--;
+ else
+ mm->context.thp_pte_count--;
+ }
+
+ /* Do not try to allocate the TSB hash table if we
+ * don't have one already. We have various locks held
+ * and thus we'll end up doing a GFP_KERNEL allocation
+ * in an atomic context.
+ *
+ * Instead, we let the first TLB miss on a hugepage
+ * take care of this.
+ */
+ }
+
+ if (!pmd_none(orig)) {
+ addr &= HPAGE_MASK;
+ if (pmd_trans_huge(orig)) {
+ pte_t orig_pte = __pte(pmd_val(orig));
+ bool exec = pte_exec(orig_pte);
+
+ tlb_batch_add_one(mm, addr, exec, REAL_HPAGE_SHIFT);
+ tlb_batch_add_one(mm, addr + REAL_HPAGE_SIZE, exec,
+ REAL_HPAGE_SHIFT);
+ } else {
+ tlb_batch_pmd_scan(mm, addr, orig);
+ }
+ }
+}
+
+void set_pmd_at(struct mm_struct *mm, unsigned long addr,
+ pmd_t *pmdp, pmd_t pmd)
+{
+ pmd_t orig = *pmdp;
+
+ *pmdp = pmd;
+ __set_pmd_acct(mm, addr, orig, pmd);
+}
+
+static inline pmd_t pmdp_establish(struct vm_area_struct *vma,
+ unsigned long address, pmd_t *pmdp, pmd_t pmd)
+{
+ pmd_t old;
+
+ do {
+ old = *pmdp;
+ } while (cmpxchg64(&pmdp->pmd, old.pmd, pmd.pmd) != old.pmd);
+ __set_pmd_acct(vma->vm_mm, address, old, pmd);
+
+ return old;
+}
+
+/*
+ * This routine is only called when splitting a THP
+ */
+pmd_t pmdp_invalidate(struct vm_area_struct *vma, unsigned long address,
+ pmd_t *pmdp)
+{
+ pmd_t old, entry;
+
+ entry = __pmd(pmd_val(*pmdp) & ~_PAGE_VALID);
+ old = pmdp_establish(vma, address, pmdp, entry);
+ flush_tlb_range(vma, address, address + HPAGE_PMD_SIZE);
+
+ /*
+ * set_pmd_at() will not be called in a way to decrement
+ * thp_pte_count when splitting a THP, so do it now.
+ * Sanity check pmd before doing the actual decrement.
+ */
+ if ((pmd_val(entry) & _PAGE_PMD_HUGE) &&
+ !is_huge_zero_page(pmd_page(entry)))
+ (vma->vm_mm)->context.thp_pte_count--;
+
+ return old;
+}
+
+void pgtable_trans_huge_deposit(struct mm_struct *mm, pmd_t *pmdp,
+ pgtable_t pgtable)
+{
+ struct list_head *lh = (struct list_head *) pgtable;
+
+ assert_spin_locked(&mm->page_table_lock);
+
+ /* FIFO */
+ if (!pmd_huge_pte(mm, pmdp))
+ INIT_LIST_HEAD(lh);
+ else
+ list_add(lh, (struct list_head *) pmd_huge_pte(mm, pmdp));
+ pmd_huge_pte(mm, pmdp) = pgtable;
+}
+
+pgtable_t pgtable_trans_huge_withdraw(struct mm_struct *mm, pmd_t *pmdp)
+{
+ struct list_head *lh;
+ pgtable_t pgtable;
+
+ assert_spin_locked(&mm->page_table_lock);
+
+ /* FIFO */
+ pgtable = pmd_huge_pte(mm, pmdp);
+ lh = (struct list_head *) pgtable;
+ if (list_empty(lh))
+ pmd_huge_pte(mm, pmdp) = NULL;
+ else {
+ pmd_huge_pte(mm, pmdp) = (pgtable_t) lh->next;
+ list_del(lh);
+ }
+ pte_val(pgtable[0]) = 0;
+ pte_val(pgtable[1]) = 0;
+
+ return pgtable;
+}
+#endif /* CONFIG_TRANSPARENT_HUGEPAGE */