Fixed return status from pagers. Ahem...the previous method would manufacture

data when it couldn't get it legitimately. :-(

Submitted by:	John Dyson

3 files changed, 25 insertions, 17 deletions

diff --git a/sys/vm/swap_pager.c b/sys/vm/swap_pager.c
index 9f0654b2..04b273b 100644
--- a/sys/vm/swap_pager.c
+++ b/sys/vm/swap_pager.c
@@ -39,7 +39,7 @@
  * from: Utah $Hdr: swap_pager.c 1.4 91/04/30$
  *
  *	@(#)swap_pager.c	8.9 (Berkeley) 3/21/94
- * $Id: swap_pager.c,v 1.15 1994/10/22 02:17:59 davidg Exp $
+ * $Id: swap_pager.c,v 1.16 1994/10/25 07:06:20 davidg Exp $
  */
 
 /*
@@ -1105,7 +1105,7 @@ swap_pager_input(swp, m, count, reqpage)
 	if (bp->b_flags & B_ERROR) {
 		printf("swap_pager: I/O error - pagein failed; blkno %d, size %d, error %d\n",
 		    bp->b_blkno, bp->b_bcount, bp->b_error);
-		rv = VM_PAGER_FAIL;
+		rv = VM_PAGER_ERROR;
 	} else {
 		rv = VM_PAGER_OK;
 	}
@@ -1506,7 +1506,7 @@ retrygetspace:
 	if (bp->b_flags & B_ERROR) {
 		printf("swap_pager: I/O error - pageout failed; blkno %d, size %d, error %d\n",
 		    bp->b_blkno, bp->b_bcount, bp->b_error);
-		rv = VM_PAGER_FAIL;
+		rv = VM_PAGER_ERROR;
 	} else {
 		rv = VM_PAGER_OK;
 	}
@@ -1632,7 +1632,7 @@ swap_pager_finish(spc)
 	 */
 	if (spc->spc_flags & SPC_ERROR) {
 		for(i=0;i<spc->spc_count;i++) {
-			printf("swap_pager_finish: clean of page %lx failed\n",
+			printf("swap_pager_finish: I/O error, clean of page %lx failed\n",
 			       (u_long)VM_PAGE_TO_PHYS(spc->spc_m[i]));
 			spc->spc_m[i]->flags |= PG_LAUNDRY;
 		}
diff --git a/sys/vm/vm_fault.c b/sys/vm/vm_fault.c
index 586f772..eb0048c 100644
--- a/sys/vm/vm_fault.c
+++ b/sys/vm/vm_fault.c
@@ -66,7 +66,7 @@
  * any improvements or extensions that they make and grant Carnegie the
  * rights to redistribute these changes.
  *
- * $Id: vm_fault.c,v 1.10 1994/10/22 02:18:01 davidg Exp $
+ * $Id: vm_fault.c,v 1.11 1994/10/23 06:15:03 davidg Exp $
  */
 
 /*
@@ -83,6 +83,7 @@
 #include <vm/vm.h>
 #include <vm/vm_page.h>
 #include <vm/vm_pageout.h>
+#include <vm/vm_kern.h>
 
 int	vm_fault_additional_pages __P((vm_object_t, vm_offset_t, vm_page_t, int, int, vm_page_t *, int *));
 
@@ -422,14 +423,21 @@ vm_fault(map, vaddr, fault_type, change_wiring)
 			 *	that we are.
 			 */
 
+			if (rv == VM_PAGER_ERROR)
+				printf("vm_fault: pager input (probably hardware) error, PID %d failure\n",
+				curproc->p_pid);
 			vm_object_lock(object);
 			/*
-			 * Data outside the range of the pager; an error
+			 * Data outside the range of the pager or an I/O error
 			 */
-			if ((rv == VM_PAGER_ERROR) || (rv == VM_PAGER_BAD)) {
+			/*
+			 * XXX - the check for kernel_map is a kludge to work around
+			 * having the machine panic on a kernel space fault w/ I/O error.
+			 */
+			if (((map != kernel_map) && (rv == VM_PAGER_ERROR)) || (rv == VM_PAGER_BAD)) {
 				FREE_PAGE(m);
 				UNLOCK_AND_DEALLOCATE;
-				return(KERN_PROTECTION_FAILURE); /* XXX */
+				return ((rv == VM_PAGER_ERROR) ? KERN_FAILURE : KERN_PROTECTION_FAILURE);
 			}
 			if (object != first_object) {
 				FREE_PAGE(m);
diff --git a/sys/vm/vnode_pager.c b/sys/vm/vnode_pager.c
index a194588..19f40e3 100644
--- a/sys/vm/vnode_pager.c
+++ b/sys/vm/vnode_pager.c
@@ -37,7 +37,7 @@
  * SUCH DAMAGE.
  *
  *	from: @(#)vnode_pager.c	7.5 (Berkeley) 4/20/91
- *	$Id: vnode_pager.c,v 1.13 1994/10/14 12:26:18 davidg Exp $
+ *	$Id: vnode_pager.c,v 1.14 1994/10/15 13:33:09 davidg Exp $
  */
 
 /*
@@ -688,7 +688,7 @@ nextblock:
 	}
 	vm_pager_unmap_page(kva);
 	if (error) {
-		return VM_PAGER_FAIL;
+		return VM_PAGER_ERROR;
 	}
 	pmap_clear_modify(VM_PAGE_TO_PHYS(m));
 	m->flags |= PG_CLEAN;
@@ -754,7 +754,7 @@ vnode_pager_input_old(vnp, m)
 	pmap_clear_modify(VM_PAGE_TO_PHYS(m));
 	m->flags |= PG_CLEAN;
 	m->flags &= ~PG_LAUNDRY;
-	return error ? VM_PAGER_FAIL : VM_PAGER_OK;
+	return error ? VM_PAGER_ERROR : VM_PAGER_OK;
 }
 
 /*
@@ -1137,9 +1137,9 @@ finishup:
 		}
 	}
 	if (error) {
-		printf("vnode_pager_input: read error\n");
+		printf("vnode_pager_input: I/O read error\n");
 	}
-	return (error ? VM_PAGER_FAIL : VM_PAGER_OK);
+	return (error ? VM_PAGER_ERROR : VM_PAGER_OK);
 }
 
 /*
@@ -1193,7 +1193,7 @@ vnode_pager_output_old(vnp, m)
 			}
 		}
 		vm_pager_unmap_page(kva);
-		return error ? VM_PAGER_FAIL : VM_PAGER_OK;
+		return error ? VM_PAGER_ERROR: VM_PAGER_OK;
 	}
 }
 
@@ -1283,7 +1283,7 @@ vnode_pager_output_smlfs(vnp, m)
 	}
 	vm_pager_unmap_page(kva);
 	if (error)
-		return VM_PAGER_FAIL;
+		return VM_PAGER_ERROR;
 	else
 		return VM_PAGER_OK;
 }
@@ -1502,7 +1502,7 @@ retryoutput:
 		goto retryoutput;
 	}
 	if (error) {
-		printf("vnode_pager_output: write error\n");
+		printf("vnode_pager_output: I/O write error\n");
 	}
-	return (error ? VM_PAGER_FAIL : VM_PAGER_OK);
+	return (error ? VM_PAGER_ERROR: VM_PAGER_OK);
 }