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

[John David Anglin <dave.anglin@xxxxxxxx>]

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 <dave.anglin@xxxxxxxx>
---

diff --git a/arch/parisc/mm/hugetlbpage.c b/arch/parisc/mm/hugetlbpage.c
index d77479ae3af2..d578809e55cf 100644
--- a/arch/parisc/mm/hugetlbpage.c
+++ b/arch/parisc/mm/hugetlbpage.c
@@ -139,9 +139,9 @@ void set_huge_pte_at(struct mm_struct *mm, unsigned long addr,
 {
 	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);
 }


@@ -151,10 +151,10 @@ pte_t huge_ptep_get_and_clear(struct mm_struct *mm, unsigned long addr,
 	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;
 }
@@ -166,10 +166,10 @@ void huge_ptep_set_wrprotect(struct mm_struct *mm,
 	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,
@@ -178,13 +178,14 @@ 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;
 }