parisc: Update huge TLB page support to use per-pagetable spinlock

This patch updates the parisc huge TLB page support to use per-pagetable spinlocks.

This patch requires Mikulas' per-pagetable spinlock patch and the revised TLB
serialization patch from Helge and myself. With Mikulas' patch, we need to use
the per-pagetable spinlock for page table updates. The TLB lock is only used
to serialize TLB flushes on machines with the Merced bus.

Signed-off-by: John David Anglin <[e-mail]>
Signed-off-by: Helge Deller <[e-mail]>

arch/parisc/mm/hugetlbpage.c

···
 {
 	unsigned long flags;
 
-	purge_tlb_start(flags);
+	spin_lock_irqsave(pgd_spinlock((mm)->pgd), flags);
 	__set_huge_pte_at(mm, addr, ptep, entry);
-	purge_tlb_end(flags);
+	spin_unlock_irqrestore(pgd_spinlock((mm)->pgd), flags);
 }
 
 
···
 	unsigned long flags;
 	pte_t entry;
 
-	purge_tlb_start(flags);
+	spin_lock_irqsave(pgd_spinlock((mm)->pgd), flags);
 	entry = *ptep;
 	__set_huge_pte_at(mm, addr, ptep, __pte(0));
-	purge_tlb_end(flags);
+	spin_unlock_irqrestore(pgd_spinlock((mm)->pgd), flags);
 
 	return entry;
 }
···
 	unsigned long flags;
 	pte_t old_pte;
 
-	purge_tlb_start(flags);
+	spin_lock_irqsave(pgd_spinlock((mm)->pgd), flags);
 	old_pte = *ptep;
 	__set_huge_pte_at(mm, addr, ptep, pte_wrprotect(old_pte));
-	purge_tlb_end(flags);
+	spin_unlock_irqrestore(pgd_spinlock((mm)->pgd), flags);
 }
 
 int huge_ptep_set_access_flags(struct vm_area_struct *vma,
···
 {
 	unsigned long flags;
 	int changed;
+	struct mm_struct *mm = vma->vm_mm;
 
-	purge_tlb_start(flags);
+	spin_lock_irqsave(pgd_spinlock((mm)->pgd), flags);
 	changed = !pte_same(*ptep, pte);
 	if (changed) {
-		__set_huge_pte_at(vma->vm_mm, addr, ptep, pte);
+		__set_huge_pte_at(mm, addr, ptep, pte);
 	}
-	purge_tlb_end(flags);
+	spin_unlock_irqrestore(pgd_spinlock((mm)->pgd), flags);
 	return changed;
 }