Module Name: src
Committed By: rmind
Date: Mon Apr 26 02:20:59 UTC 2010
Modified Files:
src/sys/uvm [rmind-uvmplock]: uvm_bio.c uvm_extern.h uvm_object.c
uvm_object.h
Log Message:
Add ubc_purge() and purge/deassociate any related UBC entries during
object (usually, vnode) destruction. Since locking (and thus object)
is required to enter/remove mappings - object is not allowed anymore
to disappear with any UBC entries left.
>From original patch by ad@ with some modifications.
To generate a diff of this commit:
cvs rdiff -u -r1.68.4.3 -r1.68.4.4 src/sys/uvm/uvm_bio.c
cvs rdiff -u -r1.162.2.3 -r1.162.2.4 src/sys/uvm/uvm_extern.h
cvs rdiff -u -r1.7.4.3 -r1.7.4.4 src/sys/uvm/uvm_object.c
cvs rdiff -u -r1.26.20.1 -r1.26.20.2 src/sys/uvm/uvm_object.h
Please note that diffs are not public domain; they are subject to the
copyright notices on the relevant files.
Modified files:
Index: src/sys/uvm/uvm_bio.c
diff -u src/sys/uvm/uvm_bio.c:1.68.4.3 src/sys/uvm/uvm_bio.c:1.68.4.4
--- src/sys/uvm/uvm_bio.c:1.68.4.3 Sun Apr 25 22:48:26 2010
+++ src/sys/uvm/uvm_bio.c Mon Apr 26 02:20:59 2010
@@ -1,4 +1,4 @@
-/* $NetBSD: uvm_bio.c,v 1.68.4.3 2010/04/25 22:48:26 rmind Exp $ */
+/* $NetBSD: uvm_bio.c,v 1.68.4.4 2010/04/26 02:20:59 rmind Exp $ */
/*
* Copyright (c) 1998 Chuck Silvers.
@@ -34,7 +34,7 @@
*/
#include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: uvm_bio.c,v 1.68.4.3 2010/04/25 22:48:26 rmind Exp $");
+__KERNEL_RCSID(0, "$NetBSD: uvm_bio.c,v 1.68.4.4 2010/04/26 02:20:59 rmind Exp $");
#include "opt_uvmhist.h"
#include "opt_ubc.h"
@@ -79,8 +79,7 @@
#define UMAP_PAGES_LOCKED 0x0001
#define UMAP_MAPPING_CACHED 0x0002
-struct ubc_map
-{
+struct ubc_map {
struct uvm_object * uobj; /* mapped object */
voff_t offset; /* offset into uobj */
voff_t writeoff; /* write offset */
@@ -91,10 +90,10 @@
LIST_ENTRY(ubc_map) hash; /* hash table */
TAILQ_ENTRY(ubc_map) inactive; /* inactive queue */
+ LIST_ENTRY(ubc_map) list; /* per-object list */
};
-static struct ubc_object
-{
+static struct ubc_object {
struct uvm_object uobj; /* glue for uvm_map() */
char *kva; /* where ubc_object is mapped */
struct ubc_map *umap; /* array of ubc_map's */
@@ -104,7 +103,6 @@
TAILQ_HEAD(ubc_inactive_head, ubc_map) *inactive;
/* inactive queues for ubc_map's */
-
} ubc_object;
const struct uvm_pagerops ubc_pager = {
@@ -449,8 +447,8 @@
/*
* The object is already referenced, so we do not need to add a ref.
+ * Lock order: UBC object -> ubc_map::uobj.
*/
-
mutex_enter(ubc_object.uobj.vmobjlock);
again:
umap = ubc_find_mapping(uobj, umap_offset);
@@ -474,6 +472,7 @@
if (oobj != NULL) {
LIST_REMOVE(umap, hash);
+ LIST_REMOVE(umap, list);
if (umap->flags & UMAP_MAPPING_CACHED) {
umap->flags &= ~UMAP_MAPPING_CACHED;
mutex_enter(oobj->vmobjlock);
@@ -489,6 +488,7 @@
umap->offset = umap_offset;
LIST_INSERT_HEAD(&ubc_object.hash[UBC_HASH(uobj, umap_offset)],
umap, hash);
+ LIST_INSERT_HEAD(&uobj->uo_ubc, umap, list);
} else {
UBC_EVCNT_INCR(wincachehit);
va = UBC_UMAP_ADDR(umap);
@@ -709,7 +709,6 @@
return error;
}
-
/*
* uvm_vnp_zerorange: set a range of bytes in a file to zero.
*/
@@ -737,3 +736,30 @@
len -= bytelen;
}
}
+
+/*
+ * ubc_purge: disassociate ubc_map structures from an empty uvm_object.
+ */
+
+void
+ubc_purge(struct uvm_object *uobj)
+{
+ struct ubc_map *umap;
+ vaddr_t va;
+
+ KASSERT(uobj->uo_npages == 0);
+
+ mutex_enter(ubc_object.uobj.vmobjlock);
+ while ((umap = LIST_FIRST(&uobj->uo_ubc)) != NULL) {
+ KASSERT(umap->refcount == 0);
+ for (va = 0; va < ubc_winsize; va += PAGE_SIZE) {
+ KASSERT(!pmap_extract(pmap_kernel(),
+ va + UBC_UMAP_ADDR(umap), NULL));
+ }
+ LIST_REMOVE(umap, list);
+ LIST_REMOVE(umap, hash);
+ umap->flags &= ~UMAP_MAPPING_CACHED;
+ umap->uobj = NULL;
+ }
+ mutex_exit(ubc_object.uobj.vmobjlock);
+}
Index: src/sys/uvm/uvm_extern.h
diff -u src/sys/uvm/uvm_extern.h:1.162.2.3 src/sys/uvm/uvm_extern.h:1.162.2.4
--- src/sys/uvm/uvm_extern.h:1.162.2.3 Fri Apr 23 21:18:00 2010
+++ src/sys/uvm/uvm_extern.h Mon Apr 26 02:20:59 2010
@@ -1,4 +1,4 @@
-/* $NetBSD: uvm_extern.h,v 1.162.2.3 2010/04/23 21:18:00 rmind Exp $ */
+/* $NetBSD: uvm_extern.h,v 1.162.2.4 2010/04/26 02:20:59 rmind Exp $ */
/*
*
@@ -579,6 +579,7 @@
void ubc_release(void *, int);
int ubc_uiomove(struct uvm_object *, struct uio *, vsize_t,
int, int);
+void ubc_purge(struct uvm_object *);
/* uvm_emap.c */
void uvm_emap_sysinit(void);
Index: src/sys/uvm/uvm_object.c
diff -u src/sys/uvm/uvm_object.c:1.7.4.3 src/sys/uvm/uvm_object.c:1.7.4.4
--- src/sys/uvm/uvm_object.c:1.7.4.3 Sat Apr 24 21:24:03 2010
+++ src/sys/uvm/uvm_object.c Mon Apr 26 02:20:59 2010
@@ -1,7 +1,7 @@
-/* $NetBSD: uvm_object.c,v 1.7.4.3 2010/04/24 21:24:03 rmind Exp $ */
+/* $NetBSD: uvm_object.c,v 1.7.4.4 2010/04/26 02:20:59 rmind Exp $ */
/*
- * Copyright (c) 2006 The NetBSD Foundation, Inc.
+ * Copyright (c) 2006, 2010 The NetBSD Foundation, Inc.
* All rights reserved.
*
* This code is derived from software contributed to The NetBSD Foundation
@@ -37,7 +37,7 @@
*/
#include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: uvm_object.c,v 1.7.4.3 2010/04/24 21:24:03 rmind Exp $");
+__KERNEL_RCSID(0, "$NetBSD: uvm_object.c,v 1.7.4.4 2010/04/26 02:20:59 rmind Exp $");
#include "opt_ddb.h"
@@ -49,8 +49,8 @@
#include <uvm/uvm.h>
#include <uvm/uvm_ddb.h>
-/* We will fetch this page count per step */
-#define FETCH_PAGECOUNT 16
+/* Page count to fetch per single step. */
+#define FETCH_PAGECOUNT 16
/*
* uvm_obj_init: initialize UVM memory object.
@@ -68,6 +68,7 @@
}
uo->pgops = ops;
TAILQ_INIT(&uo->memq);
+ LIST_INIT(&uo->uo_ubc);
uo->uo_npages = 0;
uo->uo_refs = refs;
rb_tree_init(&uo->rb_tree, &uvm_page_tree_ops);
@@ -83,6 +84,11 @@
void *tmp = NULL;
KASSERT(rb_tree_find_node_geq(&uo->rb_tree, &tmp) == NULL);
#endif
+ /* Purge any UBC entries with this object. */
+ if (__predict_false(!LIST_EMPTY(&uo->uo_ubc))) {
+ ubc_purge(uo);
+ }
+ /* Finally, safe to destory the lock. */
if (lockptr) {
KASSERT(uo->vmobjlock == lockptr);
mutex_destroy(uo->vmobjlock);
Index: src/sys/uvm/uvm_object.h
diff -u src/sys/uvm/uvm_object.h:1.26.20.1 src/sys/uvm/uvm_object.h:1.26.20.2
--- src/sys/uvm/uvm_object.h:1.26.20.1 Tue Mar 16 15:38:18 2010
+++ src/sys/uvm/uvm_object.h Mon Apr 26 02:20:59 2010
@@ -1,4 +1,4 @@
-/* $NetBSD: uvm_object.h,v 1.26.20.1 2010/03/16 15:38:18 rmind Exp $ */
+/* $NetBSD: uvm_object.h,v 1.26.20.2 2010/04/26 02:20:59 rmind Exp $ */
/*
*
@@ -41,6 +41,7 @@
* uvm_object.h
*/
+#include <sys/queue.h>
#include <sys/rb.h>
/*
@@ -54,6 +55,7 @@
int uo_npages; /* # of pages in memq */
unsigned uo_refs; /* reference count */
struct rb_tree rb_tree; /* tree of pages */
+ LIST_HEAD(,ubc_map) uo_ubc; /* ubc mappings */
};
/*
