Introduce and use a new VM interface for temporarily pinning pages. This

new interface replaces the combined use of vm_fault_quick() and
pmap_extract_and_hold() throughout the kernel.

In collaboration with:	kib@

1 files changed, 3 insertions, 20 deletions

diff --git a/sys/kern/sys_pipe.c b/sys/kern/sys_pipe.c
index 444b424..65839d6 100644
--- a/sys/kern/sys_pipe.c
+++ b/sys/kern/sys_pipe.c
@@ -747,10 +747,8 @@ pipe_build_write_buffer(wpipe, uio)
 	struct pipe *wpipe;
 	struct uio *uio;
 {
-	pmap_t pmap;
 	u_int size;
 	int i;
-	vm_offset_t addr, endaddr;
 
 	PIPE_LOCK_ASSERT(wpipe, MA_NOTOWNED);
 	KASSERT(wpipe->pipe_state & PIPE_DIRECTW,
@@ -760,25 +758,10 @@ pipe_build_write_buffer(wpipe, uio)
 	if (size > wpipe->pipe_buffer.size)
 		size = wpipe->pipe_buffer.size;
 
-	pmap = vmspace_pmap(curproc->p_vmspace);
-	endaddr = round_page((vm_offset_t)uio->uio_iov->iov_base + size);
-	addr = trunc_page((vm_offset_t)uio->uio_iov->iov_base);
-	if (endaddr < addr)
+	if ((i = vm_fault_quick_hold_pages(&curproc->p_vmspace->vm_map,
+	    (vm_offset_t)uio->uio_iov->iov_base, size, VM_PROT_READ,
+	    wpipe->pipe_map.ms, PIPENPAGES)) < 0)
 		return (EFAULT);
-	for (i = 0; addr < endaddr; addr += PAGE_SIZE, i++) {
-		/*
-		 * vm_fault_quick() can sleep.
-		 */
-	race:
-		if (vm_fault_quick((caddr_t)addr, VM_PROT_READ) < 0) {
-			vm_page_unhold_pages(wpipe->pipe_map.ms, i);
-			return (EFAULT);
-		}
-		wpipe->pipe_map.ms[i] = pmap_extract_and_hold(pmap, addr,
-		    VM_PROT_READ);
-		if (wpipe->pipe_map.ms[i] == NULL)
-			goto race;
-	}
 
 /*
  * set up the control block