# HG changeset patch
# User Keir Fraser <keir.fraser@xxxxxxxxxx>
# Date 1244107977 -3600
# Node ID a045aa7c4a77b76dd5be30b0e879087eea57e490
# Parent  b2651e8eaa82c3401ccb7e39a879016bf3b42a67
blktap2: reduce TLB flush scope

c/s 885 added very coarse TLB flushing. Since these flushes always
follow single page updates, single page flushes (when available) are
sufficient.

Signed-off-by: Jan Beulich <jbeulich@xxxxxxxxxx>

To linux-2.6-pvops:
 * Stripped arch/i386/mm/hypervisor.c exports
 * Stripped xen_invlpg_all(kvaddr) use on CONFIG_X86

Signed-off-by: Daniel Stodden <daniel.stodden@xxxxxxxxxx>

diff -r b2651e8eaa82 -r a045aa7c4a77 drivers/xen/blktap/device.c
--- a/drivers/xen/blktap/device.c	Thu Jun 04 10:32:34 2009 +0100
+++ b/drivers/xen/blktap/device.c	Thu Jun 04 10:32:57 2009 +0100
@@ -197,6 +197,12 @@
 				   PAGE_SIZE, blktap_umap_uaddr_fn, mm);
 }
 
+static inline void
+flush_tlb_kernel_page(unsigned long kvaddr)
+{
+	flush_tlb_kernel_range(kvaddr, kvaddr + PAGE_SIZE);
+}
+
 static void
 blktap_device_end_dequeued_request(struct blktap_device *dev,
 				   struct request *req, int error)
@@ -326,7 +332,7 @@
 		if (request->handles[i].kernel == INVALID_GRANT_HANDLE) {
 			kvaddr = request_to_kaddr(request, i);
 			blktap_umap_uaddr(tap->ring.vma->vm_mm, kvaddr);
-			flush_tlb_kernel_range(kvaddr, kvaddr + PAGE_SIZE);
+			flush_tlb_kernel_page(kvaddr);
 			set_phys_to_machine(__pa(kvaddr) >> PAGE_SHIFT,
 					    INVALID_P2M_ENTRY);
 		}
@@ -561,9 +567,9 @@
 
 	pte = mk_pte(page, ring->vma->vm_page_prot);
 	blktap_map_uaddr(ring->vma->vm_mm, uvaddr, pte_mkwrite(pte));
-	flush_tlb_mm(ring->vma->vm_mm);
+	flush_tlb_page(ring->vma, uvaddr);
 	blktap_map_uaddr(ring->vma->vm_mm, kvaddr, mk_pte(page, PAGE_KERNEL));
-	flush_tlb_kernel_range(kvaddr, kvaddr + PAGE_SIZE);
+	flush_tlb_kernel_page(kvaddr);
 
 	set_phys_to_machine(__pa(kvaddr) >> PAGE_SHIFT, pte_mfn(pte));
 	request->handles[seg].kernel = INVALID_GRANT_HANDLE;