-void set_huge_pte_at(struct mm_struct *mm, unsigned long addr,
- pte_t *ptep, pte_t pte)
-{
- if (pte_present(*ptep)) {
- /* We open-code pte_clear because we need to pass the right
- * argument to hpte_update (huge / !huge)
- */
- unsigned long old = pte_update(ptep, ~0UL);
- if (old & _PAGE_HASHPTE)
- hpte_update(mm, addr & HPAGE_MASK, ptep, old, 1);
- flush_tlb_pending();
- }
- *ptep = __pte(pte_val(pte) & ~_PAGE_HPTEFLAGS);
-}
-
-pte_t huge_ptep_get_and_clear(struct mm_struct *mm, unsigned long addr,
- pte_t *ptep)
-{
- unsigned long old = pte_update(ptep, ~0UL);
-
- if (old & _PAGE_HASHPTE)
- hpte_update(mm, addr & HPAGE_MASK, ptep, old, 1);
- *ptep = __pte(0);
-
- return __pte(old);
-}
-
-struct slb_flush_info {
- struct mm_struct *mm;
- u16 newareas;
-};
-
-static void flush_low_segments(void *parm)
-{
- struct slb_flush_info *fi = parm;
- unsigned long i;
-
- BUILD_BUG_ON((sizeof(fi->newareas)*8) != NUM_LOW_AREAS);
-
- if (current->active_mm != fi->mm)
- return;
-
- /* Only need to do anything if this CPU is working in the same
- * mm as the one which has changed */
-
- /* update the paca copy of the context struct */
- get_paca()->context = current->active_mm->context;
-
- asm volatile("isync" : : : "memory");
- for (i = 0; i < NUM_LOW_AREAS; i++) {
- if (! (fi->newareas & (1U << i)))
- continue;
- asm volatile("slbie %0"
- : : "r" ((i << SID_SHIFT) | SLBIE_C));
- }
- asm volatile("isync" : : : "memory");
-}
-
-static void flush_high_segments(void *parm)
-{
- struct slb_flush_info *fi = parm;
- unsigned long i, j;
-
-
- BUILD_BUG_ON((sizeof(fi->newareas)*8) != NUM_HIGH_AREAS);
-
- if (current->active_mm != fi->mm)
- return;
-
- /* Only need to do anything if this CPU is working in the same
- * mm as the one which has changed */
-
- /* update the paca copy of the context struct */
- get_paca()->context = current->active_mm->context;
-
- asm volatile("isync" : : : "memory");
- for (i = 0; i < NUM_HIGH_AREAS; i++) {
- if (! (fi->newareas & (1U << i)))
- continue;
- for (j = 0; j < (1UL << (HTLB_AREA_SHIFT-SID_SHIFT)); j++)
- asm volatile("slbie %0"
- :: "r" (((i << HTLB_AREA_SHIFT)
- + (j << SID_SHIFT)) | SLBIE_C));
- }
- asm volatile("isync" : : : "memory");
-}
-
-static int prepare_low_area_for_htlb(struct mm_struct *mm, unsigned long area)
-{
- unsigned long start = area << SID_SHIFT;
- unsigned long end = (area+1) << SID_SHIFT;
- struct vm_area_struct *vma;
-
- BUG_ON(area >= NUM_LOW_AREAS);
-
- /* Check no VMAs are in the region */
- vma = find_vma(mm, start);
- if (vma && (vma->vm_start < end))
- return -EBUSY;
-
- return 0;
-}
-
-static int prepare_high_area_for_htlb(struct mm_struct *mm, unsigned long area)
-{
- unsigned long start = area << HTLB_AREA_SHIFT;
- unsigned long end = (area+1) << HTLB_AREA_SHIFT;
- struct vm_area_struct *vma;
-
- BUG_ON(area >= NUM_HIGH_AREAS);
-
- /* Hack, so that each addresses is controlled by exactly one
- * of the high or low area bitmaps, the first high area starts
- * at 4GB, not 0 */
- if (start == 0)
- start = 0x100000000UL;
-
- /* Check no VMAs are in the region */
- vma = find_vma(mm, start);
- if (vma && (vma->vm_start < end))
- return -EBUSY;
-
- return 0;
-}
-
-static int open_low_hpage_areas(struct mm_struct *mm, u16 newareas)
-{
- unsigned long i;
- struct slb_flush_info fi;
-
- BUILD_BUG_ON((sizeof(newareas)*8) != NUM_LOW_AREAS);
- BUILD_BUG_ON((sizeof(mm->context.low_htlb_areas)*8) != NUM_LOW_AREAS);
-
- newareas &= ~(mm->context.low_htlb_areas);
- if (! newareas)
- return 0; /* The segments we want are already open */
-
- for (i = 0; i < NUM_LOW_AREAS; i++)
- if ((1 << i) & newareas)
- if (prepare_low_area_for_htlb(mm, i) != 0)
- return -EBUSY;
-
- mm->context.low_htlb_areas |= newareas;
-
- /* the context change must make it to memory before the flush,
- * so that further SLB misses do the right thing. */
- mb();
-
- fi.mm = mm;
- fi.newareas = newareas;
- on_each_cpu(flush_low_segments, &fi, 0, 1);
-
- return 0;
-}
-
-static int open_high_hpage_areas(struct mm_struct *mm, u16 newareas)
-{
- struct slb_flush_info fi;
- unsigned long i;
-
- BUILD_BUG_ON((sizeof(newareas)*8) != NUM_HIGH_AREAS);
- BUILD_BUG_ON((sizeof(mm->context.high_htlb_areas)*8)
- != NUM_HIGH_AREAS);
-
- newareas &= ~(mm->context.high_htlb_areas);
- if (! newareas)
- return 0; /* The areas we want are already open */
-
- for (i = 0; i < NUM_HIGH_AREAS; i++)
- if ((1 << i) & newareas)
- if (prepare_high_area_for_htlb(mm, i) != 0)
- return -EBUSY;
-
- mm->context.high_htlb_areas |= newareas;
-
- /* update the paca copy of the context struct */
- get_paca()->context = mm->context;
-
- /* the context change must make it to memory before the flush,
- * so that further SLB misses do the right thing. */
- mb();
-
- fi.mm = mm;
- fi.newareas = newareas;
- on_each_cpu(flush_high_segments, &fi, 0, 1);
-
- return 0;
-}
-
-int prepare_hugepage_range(unsigned long addr, unsigned long len)
-{
- int err = 0;
-
- if ( (addr+len) < addr )
- return -EINVAL;
-
- if (addr < 0x100000000UL)
- err = open_low_hpage_areas(current->mm,
- LOW_ESID_MASK(addr, len));
- if ((addr + len) > 0x100000000UL)
- err = open_high_hpage_areas(current->mm,
- HTLB_AREA_MASK(addr, len));
- if (err) {
- printk(KERN_DEBUG "prepare_hugepage_range(%lx, %lx)"
- " failed (lowmask: 0x%04hx, highmask: 0x%04hx)\n",
- addr, len,
- LOW_ESID_MASK(addr, len), HTLB_AREA_MASK(addr, len));
- return err;
- }
-
- return 0;
-}
-