Make KPI of vm_pager_get_pages() more strict: if a pager changes a page

in the requested array, then it is responsible for disposition of previous
page and is responsible for updating the entry in the requested array.
Now consumers of KPI do not need to re-lookup the pages after call to
vm_pager_get_pages().

Reviewed by:	kib
Sponsored by:	Netflix
Sponsored by:	Nginx, Inc.

1 files changed, 4 insertions, 7 deletions

diff --git a/sys/kern/kern_exec.c b/sys/kern/kern_exec.c
index d3ae4f0..375e644 100644
--- a/sys/kern/kern_exec.c
+++ b/sys/kern/kern_exec.c
@@ -966,13 +966,10 @@ exec_map_first_page(imgp)
 		}
 		initial_pagein = i;
 		rv = vm_pager_get_pages(object, ma, initial_pagein, 0);
-		ma[0] = vm_page_lookup(object, 0);
-		if ((rv != VM_PAGER_OK) || (ma[0] == NULL)) {
-			if (ma[0] != NULL) {
-				vm_page_lock(ma[0]);
-				vm_page_free(ma[0]);
-				vm_page_unlock(ma[0]);
-			}
+		if (rv != VM_PAGER_OK) {
+			vm_page_lock(ma[0]);
+			vm_page_free(ma[0]);
+			vm_page_unlock(ma[0]);
 			VM_OBJECT_WUNLOCK(object);
 			return (EIO);
 		}