Add pmap function pmap_copy_pages(), which copies the content of the

pages around, taking array of vm_page_t both for source and
destination.  Starting offsets and total transfer size are specified.

The function implements optimal algorithm for copying using the
platform-specific optimizations.  For instance, on the architectures
were the direct map is available, no transient mappings are created,
for i386 the per-cpu ephemeral page frame is used.  The code was
typically borrowed from the pmap_copy_page() for the same
architecture.

Only i386/amd64, powerpc aim and arm/arm-v6 implementations were
tested at the time of commit. High-level code, not committed yet to
the tree, ensures that the use of the function is only allowed after
explicit enablement.

For sparc64, the existing code has known issues and a stab is added
instead, to allow the kernel linking.

Sponsored by:	The FreeBSD Foundation
Tested by:	pho (i386, amd64), scottl (amd64), ian (arm and arm-v6)
MFC after:	2 weeks

1 files changed, 33 insertions, 0 deletions

diff --git a/sys/powerpc/booke/pmap.c b/sys/powerpc/booke/pmap.c
index 343b046..b9f4838 100644
--- a/sys/powerpc/booke/pmap.c
+++ b/sys/powerpc/booke/pmap.c
@@ -274,6 +274,8 @@ static void		mmu_booke_clear_reference(mmu_t, vm_page_t);
 static void		mmu_booke_copy(mmu_t, pmap_t, pmap_t, vm_offset_t,
     vm_size_t, vm_offset_t);
 static void		mmu_booke_copy_page(mmu_t, vm_page_t, vm_page_t);
+static void		mmu_booke_copy_pages(mmu_t, vm_page_t *,
+    vm_offset_t, vm_page_t *, vm_offset_t, int);
 static void		mmu_booke_enter(mmu_t, pmap_t, vm_offset_t, vm_page_t,
     vm_prot_t, boolean_t);
 static void		mmu_booke_enter_object(mmu_t, pmap_t, vm_offset_t, vm_offset_t,
@@ -334,6 +336,7 @@ static mmu_method_t mmu_booke_methods[] = {
 	MMUMETHOD(mmu_clear_reference,	mmu_booke_clear_reference),
 	MMUMETHOD(mmu_copy,		mmu_booke_copy),
 	MMUMETHOD(mmu_copy_page,	mmu_booke_copy_page),
+	MMUMETHOD(mmu_copy_pages,	mmu_booke_copy_pages),
 	MMUMETHOD(mmu_enter,		mmu_booke_enter),
 	MMUMETHOD(mmu_enter_object,	mmu_booke_enter_object),
 	MMUMETHOD(mmu_enter_quick,	mmu_booke_enter_quick),
@@ -2136,6 +2139,36 @@ mmu_booke_copy_page(mmu_t mmu, vm_page_t sm, vm_page_t dm)
 	mtx_unlock(&copy_page_mutex);
 }
 
+static inline void
+mmu_booke_copy_pages(mmu_t mmu, vm_page_t *ma, vm_offset_t a_offset,
+    vm_page_t *mb, vm_offset_t b_offset, int xfersize)
+{
+	void *a_cp, *b_cp;
+	vm_offset_t a_pg_offset, b_pg_offset;
+	int cnt;
+
+	mtx_lock(&copy_page_mutex);
+	while (xfersize > 0) {
+		a_pg_offset = a_offset & PAGE_MASK;
+		cnt = min(xfersize, PAGE_SIZE - a_pg_offset);
+		mmu_booke_kenter(mmu, copy_page_src_va,
+		    VM_PAGE_TO_PHYS(ma[a_offset >> PAGE_SHIFT]));
+		a_cp = (char *)copy_page_src_va + a_pg_offset;
+		b_pg_offset = b_offset & PAGE_MASK;
+		cnt = min(cnt, PAGE_SIZE - b_pg_offset);
+		mmu_booke_kenter(mmu, copy_page_dst_va,
+		    VM_PAGE_TO_PHYS(mb[b_offset >> PAGE_SHIFT]));
+		b_cp = (char *)copy_page_dst_va + b_pg_offset;
+		bcopy(a_cp, b_cp, cnt);
+		mmu_booke_kremove(mmu, copy_page_dst_va);
+		mmu_booke_kremove(mmu, copy_page_src_va);
+		a_offset += cnt;
+		b_offset += cnt;
+		xfersize -= cnt;
+	}
+	mtx_unlock(&copy_page_mutex);
+}
+
 /*
  * mmu_booke_zero_page_idle zeros the specified hardware page by mapping it
  * into virtual memory and using bzero to clear its contents. This is intended