[Feature]add MT2731_MP2_MR2_SVN388 baseline version
Change-Id: Ief04314834b31e27effab435d3ca8ba33b499059
diff --git a/src/kernel/linux/v4.14/arch/powerpc/mm/subpage-prot.c b/src/kernel/linux/v4.14/arch/powerpc/mm/subpage-prot.c
new file mode 100644
index 0000000..781532d
--- /dev/null
+++ b/src/kernel/linux/v4.14/arch/powerpc/mm/subpage-prot.c
@@ -0,0 +1,266 @@
+/*
+ * Copyright 2007-2008 Paul Mackerras, IBM Corp.
+ *
+ * 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/errno.h>
+#include <linux/kernel.h>
+#include <linux/gfp.h>
+#include <linux/types.h>
+#include <linux/mm.h>
+#include <linux/hugetlb.h>
+
+#include <asm/pgtable.h>
+#include <linux/uaccess.h>
+#include <asm/tlbflush.h>
+
+/*
+ * Free all pages allocated for subpage protection maps and pointers.
+ * Also makes sure that the subpage_prot_table structure is
+ * reinitialized for the next user.
+ */
+void subpage_prot_free(struct mm_struct *mm)
+{
+ struct subpage_prot_table *spt = &mm->context.spt;
+ unsigned long i, j, addr;
+ u32 **p;
+
+ for (i = 0; i < 4; ++i) {
+ if (spt->low_prot[i]) {
+ free_page((unsigned long)spt->low_prot[i]);
+ spt->low_prot[i] = NULL;
+ }
+ }
+ addr = 0;
+ for (i = 0; i < (TASK_SIZE_USER64 >> 43); ++i) {
+ p = spt->protptrs[i];
+ if (!p)
+ continue;
+ spt->protptrs[i] = NULL;
+ for (j = 0; j < SBP_L2_COUNT && addr < spt->maxaddr;
+ ++j, addr += PAGE_SIZE)
+ if (p[j])
+ free_page((unsigned long)p[j]);
+ free_page((unsigned long)p);
+ }
+ spt->maxaddr = 0;
+}
+
+void subpage_prot_init_new_context(struct mm_struct *mm)
+{
+ struct subpage_prot_table *spt = &mm->context.spt;
+
+ memset(spt, 0, sizeof(*spt));
+}
+
+static void hpte_flush_range(struct mm_struct *mm, unsigned long addr,
+ int npages)
+{
+ pgd_t *pgd;
+ pud_t *pud;
+ pmd_t *pmd;
+ pte_t *pte;
+ spinlock_t *ptl;
+
+ pgd = pgd_offset(mm, addr);
+ if (pgd_none(*pgd))
+ return;
+ pud = pud_offset(pgd, addr);
+ if (pud_none(*pud))
+ return;
+ pmd = pmd_offset(pud, addr);
+ if (pmd_none(*pmd))
+ return;
+ pte = pte_offset_map_lock(mm, pmd, addr, &ptl);
+ arch_enter_lazy_mmu_mode();
+ for (; npages > 0; --npages) {
+ pte_update(mm, addr, pte, 0, 0, 0);
+ addr += PAGE_SIZE;
+ ++pte;
+ }
+ arch_leave_lazy_mmu_mode();
+ pte_unmap_unlock(pte - 1, ptl);
+}
+
+/*
+ * Clear the subpage protection map for an address range, allowing
+ * all accesses that are allowed by the pte permissions.
+ */
+static void subpage_prot_clear(unsigned long addr, unsigned long len)
+{
+ struct mm_struct *mm = current->mm;
+ struct subpage_prot_table *spt = &mm->context.spt;
+ u32 **spm, *spp;
+ unsigned long i;
+ size_t nw;
+ unsigned long next, limit;
+
+ down_write(&mm->mmap_sem);
+ limit = addr + len;
+ if (limit > spt->maxaddr)
+ limit = spt->maxaddr;
+ for (; addr < limit; addr = next) {
+ next = pmd_addr_end(addr, limit);
+ if (addr < 0x100000000UL) {
+ spm = spt->low_prot;
+ } else {
+ spm = spt->protptrs[addr >> SBP_L3_SHIFT];
+ if (!spm)
+ continue;
+ }
+ spp = spm[(addr >> SBP_L2_SHIFT) & (SBP_L2_COUNT - 1)];
+ if (!spp)
+ continue;
+ spp += (addr >> PAGE_SHIFT) & (SBP_L1_COUNT - 1);
+
+ i = (addr >> PAGE_SHIFT) & (PTRS_PER_PTE - 1);
+ nw = PTRS_PER_PTE - i;
+ if (addr + (nw << PAGE_SHIFT) > next)
+ nw = (next - addr) >> PAGE_SHIFT;
+
+ memset(spp, 0, nw * sizeof(u32));
+
+ /* now flush any existing HPTEs for the range */
+ hpte_flush_range(mm, addr, nw);
+ }
+ up_write(&mm->mmap_sem);
+}
+
+#ifdef CONFIG_TRANSPARENT_HUGEPAGE
+static int subpage_walk_pmd_entry(pmd_t *pmd, unsigned long addr,
+ unsigned long end, struct mm_walk *walk)
+{
+ struct vm_area_struct *vma = walk->vma;
+ split_huge_pmd(vma, pmd, addr);
+ return 0;
+}
+
+static void subpage_mark_vma_nohuge(struct mm_struct *mm, unsigned long addr,
+ unsigned long len)
+{
+ struct vm_area_struct *vma;
+ struct mm_walk subpage_proto_walk = {
+ .mm = mm,
+ .pmd_entry = subpage_walk_pmd_entry,
+ };
+
+ /*
+ * We don't try too hard, we just mark all the vma in that range
+ * VM_NOHUGEPAGE and split them.
+ */
+ vma = find_vma(mm, addr);
+ /*
+ * If the range is in unmapped range, just return
+ */
+ if (vma && ((addr + len) <= vma->vm_start))
+ return;
+
+ while (vma) {
+ if (vma->vm_start >= (addr + len))
+ break;
+ vma->vm_flags |= VM_NOHUGEPAGE;
+ walk_page_vma(vma, &subpage_proto_walk);
+ vma = vma->vm_next;
+ }
+}
+#else
+static void subpage_mark_vma_nohuge(struct mm_struct *mm, unsigned long addr,
+ unsigned long len)
+{
+ return;
+}
+#endif
+
+/*
+ * Copy in a subpage protection map for an address range.
+ * The map has 2 bits per 4k subpage, so 32 bits per 64k page.
+ * Each 2-bit field is 0 to allow any access, 1 to prevent writes,
+ * 2 or 3 to prevent all accesses.
+ * Note that the normal page protections also apply; the subpage
+ * protection mechanism is an additional constraint, so putting 0
+ * in a 2-bit field won't allow writes to a page that is otherwise
+ * write-protected.
+ */
+long sys_subpage_prot(unsigned long addr, unsigned long len, u32 __user *map)
+{
+ struct mm_struct *mm = current->mm;
+ struct subpage_prot_table *spt = &mm->context.spt;
+ u32 **spm, *spp;
+ unsigned long i;
+ size_t nw;
+ unsigned long next, limit;
+ int err;
+
+ /* Check parameters */
+ if ((addr & ~PAGE_MASK) || (len & ~PAGE_MASK) ||
+ addr >= mm->task_size || len >= mm->task_size ||
+ addr + len > mm->task_size)
+ return -EINVAL;
+
+ if (is_hugepage_only_range(mm, addr, len))
+ return -EINVAL;
+
+ if (!map) {
+ /* Clear out the protection map for the address range */
+ subpage_prot_clear(addr, len);
+ return 0;
+ }
+
+ if (!access_ok(VERIFY_READ, map, (len >> PAGE_SHIFT) * sizeof(u32)))
+ return -EFAULT;
+
+ down_write(&mm->mmap_sem);
+ subpage_mark_vma_nohuge(mm, addr, len);
+ for (limit = addr + len; addr < limit; addr = next) {
+ next = pmd_addr_end(addr, limit);
+ err = -ENOMEM;
+ if (addr < 0x100000000UL) {
+ spm = spt->low_prot;
+ } else {
+ spm = spt->protptrs[addr >> SBP_L3_SHIFT];
+ if (!spm) {
+ spm = (u32 **)get_zeroed_page(GFP_KERNEL);
+ if (!spm)
+ goto out;
+ spt->protptrs[addr >> SBP_L3_SHIFT] = spm;
+ }
+ }
+ spm += (addr >> SBP_L2_SHIFT) & (SBP_L2_COUNT - 1);
+ spp = *spm;
+ if (!spp) {
+ spp = (u32 *)get_zeroed_page(GFP_KERNEL);
+ if (!spp)
+ goto out;
+ *spm = spp;
+ }
+ spp += (addr >> PAGE_SHIFT) & (SBP_L1_COUNT - 1);
+
+ local_irq_disable();
+ demote_segment_4k(mm, addr);
+ local_irq_enable();
+
+ i = (addr >> PAGE_SHIFT) & (PTRS_PER_PTE - 1);
+ nw = PTRS_PER_PTE - i;
+ if (addr + (nw << PAGE_SHIFT) > next)
+ nw = (next - addr) >> PAGE_SHIFT;
+
+ up_write(&mm->mmap_sem);
+ if (__copy_from_user(spp, map, nw * sizeof(u32)))
+ return -EFAULT;
+ map += nw;
+ down_write(&mm->mmap_sem);
+
+ /* now flush any existing HPTEs for the range */
+ hpte_flush_range(mm, addr, nw);
+ }
+ if (limit > spt->maxaddr)
+ spt->maxaddr = limit;
+ err = 0;
+ out:
+ up_write(&mm->mmap_sem);
+ return err;
+}