Implement pmap_unwire(). See r268327 for the motivation behind this change.

1 files changed, 32 insertions, 0 deletions

diff --git a/sys/powerpc/booke/pmap.c b/sys/powerpc/booke/pmap.c
index 57df896..d640d90 100644
--- a/sys/powerpc/booke/pmap.c
+++ b/sys/powerpc/booke/pmap.c
@@ -306,6 +306,7 @@ static void		mmu_booke_release(mmu_t, pmap_t);
 static void		mmu_booke_remove(mmu_t, pmap_t, vm_offset_t, vm_offset_t);
 static void		mmu_booke_remove_all(mmu_t, vm_page_t);
 static void		mmu_booke_remove_write(mmu_t, vm_page_t);
+static void		mmu_booke_unwire(mmu_t, pmap_t, vm_offset_t, vm_offset_t);
 static void		mmu_booke_zero_page(mmu_t, vm_page_t);
 static void		mmu_booke_zero_page_area(mmu_t, vm_page_t, int, int);
 static void		mmu_booke_zero_page_idle(mmu_t, vm_page_t);
@@ -361,6 +362,7 @@ static mmu_method_t mmu_booke_methods[] = {
 	MMUMETHOD(mmu_remove_all,	mmu_booke_remove_all),
 	MMUMETHOD(mmu_remove_write,	mmu_booke_remove_write),
 	MMUMETHOD(mmu_sync_icache,	mmu_booke_sync_icache),
+	MMUMETHOD(mmu_unwire,		mmu_booke_unwire),
 	MMUMETHOD(mmu_zero_page,	mmu_booke_zero_page),
 	MMUMETHOD(mmu_zero_page_area,	mmu_booke_zero_page_area),
 	MMUMETHOD(mmu_zero_page_idle,	mmu_booke_zero_page_idle),
@@ -2435,6 +2437,36 @@ mmu_booke_change_wiring(mmu_t mmu, pmap_t pmap, vm_offset_t va, boolean_t wired)
 }
 
 /*
+ * Clear the wired attribute from the mappings for the specified range of
+ * addresses in the given pmap.  Every valid mapping within that range must
+ * have the wired attribute set.  In contrast, invalid mappings cannot have
+ * the wired attribute set, so they are ignored.
+ *
+ * The wired attribute of the page table entry is not a hardware feature, so
+ * there is no need to invalidate any TLB entries.
+ */
+static void
+mmu_booke_unwire(mmu_t mmu, pmap_t pmap, vm_offset_t sva, vm_offset_t eva)
+{
+	vm_offset_t va;
+	pte_t *pte;
+
+	PMAP_LOCK(pmap);
+	for (va = sva; va < eva; va += PAGE_SIZE) {
+		if ((pte = pte_find(mmu, pmap, va)) != NULL &&
+		    PTE_ISVALID(pte)) {
+			if (!PTE_ISWIRED(pte))
+				panic("mmu_booke_unwire: pte %p isn't wired",
+				    pte);
+			pte->flags &= ~PTE_WIRED;
+			pmap->pm_stats.wired_count--;
+		}
+	}
+	PMAP_UNLOCK(pmap);
+
+}
+
+/*
  * Return true if the pmap's pv is one of the first 16 pvs linked to from this
  * page.  This count may be changed upwards or downwards in the future; it is
  * only necessary that true be returned for a small subset of pmaps for proper