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, 5 insertions, 9 deletions

diff --git a/sys/kern/uipc_cow.c b/sys/kern/uipc_cow.c
index 853b70b..f7ef798 100644
--- a/sys/kern/uipc_cow.c
+++ b/sys/kern/uipc_cow.c
@@ -103,24 +103,20 @@ socow_setup(struct mbuf *m0, struct uio *uio)
 	struct vmspace *vmspace;
 	struct vm_map *map;
 	vm_offset_t offset, uva;
+	vm_size_t len;
 
 	socow_stats.attempted++;
 	vmspace = curproc->p_vmspace;
 	map = &vmspace->vm_map;
 	uva = (vm_offset_t) uio->uio_iov->iov_base;
 	offset = uva & PAGE_MASK;
+	len = PAGE_SIZE - offset;
 
 	/*
 	 * Verify that access to the given address is allowed from user-space.
 	 */
-	if (vm_fault_quick((caddr_t)uva, VM_PROT_READ) < 0)
-		return (0);
-
-       /* 
-	* verify page is mapped & not already wired for i/o
-	*/
-	pp = pmap_extract_and_hold(map->pmap, uva, VM_PROT_READ);
-	if (pp == NULL) {
+	if (vm_fault_quick_hold_pages(map, uva, len, &pp, 1, VM_PROT_READ) <
+	    0) {
 		socow_stats.fail_not_mapped++;
 		return(0);
 	}
@@ -165,7 +161,7 @@ socow_setup(struct mbuf *m0, struct uio *uio)
 	 */
 	MEXTADD(m0, sf_buf_kva(sf), PAGE_SIZE, socow_iodone,
 	    (void*)sf_buf_kva(sf), sf, M_RDONLY, EXT_SFBUF);
-	m0->m_len = PAGE_SIZE - offset;
+	m0->m_len = len;
 	m0->m_data = (caddr_t)sf_buf_kva(sf) + offset;
 	socow_stats.success++;