Module Name: src
Committed By: hannken
Date: Thu Mar 30 09:16:53 UTC 2017
Modified Files:
src/sys/kern: vfs_vnode.c
src/sys/miscfs/genfs: genfs_vnops.c layer_extern.h layer_vfsops.c
layer_vnops.c
src/sys/miscfs/nullfs: null_vnops.c
src/sys/miscfs/overlay: overlay_vnops.c
src/sys/miscfs/umapfs: umap_vnops.c
src/sys/sys: param.h vnode.h vnode_impl.h
Log Message:
Locking a layer vnode is racy as it may become reclaimed before
calling the operation on the lower vnode.
Replace vi_lock with a rw_obj and change layered file systems
to share the lock with the lower vnode.
Layered file systems now use genfs_lock()/_unlock/_islocked().
Welcome to 7.99.67
To generate a diff of this commit:
cvs rdiff -u -r1.80 -r1.81 src/sys/kern/vfs_vnode.c
cvs rdiff -u -r1.193 -r1.194 src/sys/miscfs/genfs/genfs_vnops.c
cvs rdiff -u -r1.38 -r1.39 src/sys/miscfs/genfs/layer_extern.h
cvs rdiff -u -r1.47 -r1.48 src/sys/miscfs/genfs/layer_vfsops.c
cvs rdiff -u -r1.60 -r1.61 src/sys/miscfs/genfs/layer_vnops.c
cvs rdiff -u -r1.40 -r1.41 src/sys/miscfs/nullfs/null_vnops.c
cvs rdiff -u -r1.22 -r1.23 src/sys/miscfs/overlay/overlay_vnops.c
cvs rdiff -u -r1.58 -r1.59 src/sys/miscfs/umapfs/umap_vnops.c
cvs rdiff -u -r1.533 -r1.534 src/sys/sys/param.h
cvs rdiff -u -r1.274 -r1.275 src/sys/sys/vnode.h
cvs rdiff -u -r1.12 -r1.13 src/sys/sys/vnode_impl.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/kern/vfs_vnode.c
diff -u src/sys/kern/vfs_vnode.c:1.80 src/sys/kern/vfs_vnode.c:1.81
--- src/sys/kern/vfs_vnode.c:1.80 Thu Mar 30 09:15:51 2017
+++ src/sys/kern/vfs_vnode.c Thu Mar 30 09:16:52 2017
@@ -1,4 +1,4 @@
-/* $NetBSD: vfs_vnode.c,v 1.80 2017/03/30 09:15:51 hannken Exp $ */
+/* $NetBSD: vfs_vnode.c,v 1.81 2017/03/30 09:16:52 hannken Exp $ */
/*-
* Copyright (c) 1997-2011 The NetBSD Foundation, Inc.
@@ -156,7 +156,7 @@
*/
#include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: vfs_vnode.c,v 1.80 2017/03/30 09:15:51 hannken Exp $");
+__KERNEL_RCSID(0, "$NetBSD: vfs_vnode.c,v 1.81 2017/03/30 09:16:52 hannken Exp $");
#include <sys/param.h>
#include <sys/kernel.h>
@@ -416,6 +416,21 @@ vnis_marker(vnode_t *vp)
}
/*
+ * Set vnode to share another vnodes lock.
+ */
+void
+vshare_lock(vnode_t *vp, vnode_t *src_vp)
+{
+ vnode_impl_t *vip = VNODE_TO_VIMPL(vp);
+ vnode_impl_t *src_vip = VNODE_TO_VIMPL(src_vp);
+ krwlock_t *oldlock = vip->vi_lock;
+
+ rw_obj_hold(src_vip->vi_lock);
+ vip->vi_lock = src_vip->vi_lock;
+ rw_obj_free(oldlock);
+}
+
+/*
* Return the lru list this node should be on.
*/
static vnodelst_t *
@@ -1066,7 +1081,7 @@ vcache_alloc(void)
vip = pool_cache_get(vcache_pool, PR_WAITOK);
memset(vip, 0, sizeof(*vip));
- rw_init(&vip->vi_lock);
+ vip->vi_lock = rw_obj_alloc();
/* SLIST_INIT(&vip->vi_hash); */
/* LIST_INIT(&vip->vi_nclist); */
/* LIST_INIT(&vip->vi_dnclist); */
@@ -1128,7 +1143,7 @@ vcache_free(vnode_impl_t *vip)
if (vp->v_type == VBLK || vp->v_type == VCHR)
spec_node_destroy(vp);
- rw_destroy(&vip->vi_lock);
+ rw_obj_free(vip->vi_lock);
uvm_obj_destroy(&vp->v_uobj, true);
cv_destroy(&vp->v_cv);
pool_cache_put(vcache_pool, vip);
Index: src/sys/miscfs/genfs/genfs_vnops.c
diff -u src/sys/miscfs/genfs/genfs_vnops.c:1.193 src/sys/miscfs/genfs/genfs_vnops.c:1.194
--- src/sys/miscfs/genfs/genfs_vnops.c:1.193 Wed Jan 11 09:08:59 2017
+++ src/sys/miscfs/genfs/genfs_vnops.c Thu Mar 30 09:16:52 2017
@@ -1,4 +1,4 @@
-/* $NetBSD: genfs_vnops.c,v 1.193 2017/01/11 09:08:59 hannken Exp $ */
+/* $NetBSD: genfs_vnops.c,v 1.194 2017/03/30 09:16:52 hannken Exp $ */
/*-
* Copyright (c) 2008 The NetBSD Foundation, Inc.
@@ -57,7 +57,7 @@
*/
#include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: genfs_vnops.c,v 1.193 2017/01/11 09:08:59 hannken Exp $");
+__KERNEL_RCSID(0, "$NetBSD: genfs_vnops.c,v 1.194 2017/03/30 09:16:52 hannken Exp $");
#include <sys/param.h>
#include <sys/systm.h>
@@ -295,7 +295,7 @@ genfs_deadlock(void *v)
op = (ISSET(flags, LK_EXCLUSIVE) ? RW_WRITER : RW_READER);
if (ISSET(flags, LK_NOWAIT)) {
- if (! rw_tryenter(&vip->vi_lock, op))
+ if (! rw_tryenter(vip->vi_lock, op))
return EBUSY;
if (mutex_tryenter(vp->v_interlock)) {
error = vdead_check(vp, VDEAD_NOWAIT);
@@ -305,25 +305,25 @@ genfs_deadlock(void *v)
} else
error = EBUSY;
if (error)
- rw_exit(&vip->vi_lock);
+ rw_exit(vip->vi_lock);
return error;
}
- rw_enter(&vip->vi_lock, op);
+ rw_enter(vip->vi_lock, op);
mutex_enter(vp->v_interlock);
error = vdead_check(vp, VDEAD_NOWAIT);
if (error == EBUSY) {
- rw_exit(&vip->vi_lock);
+ rw_exit(vip->vi_lock);
error = vdead_check(vp, 0);
KASSERT(error == ENOENT);
mutex_exit(vp->v_interlock);
- rw_enter(&vip->vi_lock, op);
+ rw_enter(vip->vi_lock, op);
mutex_enter(vp->v_interlock);
}
KASSERT(error == ENOENT);
mutex_exit(vp->v_interlock);
if (! ISSET(flags, LK_RETRY)) {
- rw_exit(&vip->vi_lock);
+ rw_exit(vip->vi_lock);
return ENOENT;
}
return 0;
@@ -341,7 +341,7 @@ genfs_deadunlock(void *v)
vnode_t *vp = ap->a_vp;
vnode_impl_t *vip = VNODE_TO_VIMPL(vp);
- rw_exit(&vip->vi_lock);
+ rw_exit(vip->vi_lock);
return 0;
}
@@ -367,7 +367,7 @@ genfs_lock(void *v)
if (ISSET(flags, LK_NOWAIT)) {
if (fstrans_start_nowait(mp, FSTRANS_SHARED))
return EBUSY;
- if (! rw_tryenter(&vip->vi_lock, op)) {
+ if (! rw_tryenter(vip->vi_lock, op)) {
fstrans_done(mp);
return EBUSY;
}
@@ -377,18 +377,18 @@ genfs_lock(void *v)
} else
error = EBUSY;
if (error) {
- rw_exit(&vip->vi_lock);
+ rw_exit(vip->vi_lock);
fstrans_done(mp);
}
return error;
}
fstrans_start(mp, FSTRANS_SHARED);
- rw_enter(&vip->vi_lock, op);
+ rw_enter(vip->vi_lock, op);
mutex_enter(vp->v_interlock);
error = vdead_check(vp, VDEAD_NOWAIT);
if (error) {
- rw_exit(&vip->vi_lock);
+ rw_exit(vip->vi_lock);
fstrans_done(mp);
error = vdead_check(vp, 0);
KASSERT(error == ENOENT);
@@ -410,7 +410,7 @@ genfs_unlock(void *v)
vnode_impl_t *vip = VNODE_TO_VIMPL(vp);
struct mount *mp = vp->v_mount;
- rw_exit(&vip->vi_lock);
+ rw_exit(vip->vi_lock);
fstrans_done(mp);
return 0;
@@ -428,10 +428,10 @@ genfs_islocked(void *v)
vnode_t *vp = ap->a_vp;
vnode_impl_t *vip = VNODE_TO_VIMPL(vp);
- if (rw_write_held(&vip->vi_lock))
+ if (rw_write_held(vip->vi_lock))
return LK_EXCLUSIVE;
- if (rw_read_held(&vip->vi_lock))
+ if (rw_read_held(vip->vi_lock))
return LK_SHARED;
return 0;
Index: src/sys/miscfs/genfs/layer_extern.h
diff -u src/sys/miscfs/genfs/layer_extern.h:1.38 src/sys/miscfs/genfs/layer_extern.h:1.39
--- src/sys/miscfs/genfs/layer_extern.h:1.38 Fri Feb 17 08:31:25 2017
+++ src/sys/miscfs/genfs/layer_extern.h Thu Mar 30 09:16:52 2017
@@ -1,4 +1,4 @@
-/* $NetBSD: layer_extern.h,v 1.38 2017/02/17 08:31:25 hannken Exp $ */
+/* $NetBSD: layer_extern.h,v 1.39 2017/03/30 09:16:52 hannken Exp $ */
/*
* Copyright (c) 1999 National Aeronautics & Space Administration
@@ -99,7 +99,6 @@ int layer_bypass(void *);
int layer_getattr(void *);
int layer_inactive(void *);
int layer_reclaim(void *);
-int layer_lock(void *);
int layer_print(void *);
int layer_bmap(void *);
int layer_fsync(void *);
@@ -114,5 +113,8 @@ int layer_revoke(void *);
int layer_rmdir(void *);
int layer_getpages(void *);
int layer_putpages(void *);
+#define layer_lock genfs_lock
+#define layer_unlock genfs_unlock
+#define layer_islocked genfs_islocked
#endif /* _MISCFS_GENFS_LAYER_EXTERN_H_ */
Index: src/sys/miscfs/genfs/layer_vfsops.c
diff -u src/sys/miscfs/genfs/layer_vfsops.c:1.47 src/sys/miscfs/genfs/layer_vfsops.c:1.48
--- src/sys/miscfs/genfs/layer_vfsops.c:1.47 Fri Feb 17 08:31:25 2017
+++ src/sys/miscfs/genfs/layer_vfsops.c Thu Mar 30 09:16:52 2017
@@ -1,4 +1,4 @@
-/* $NetBSD: layer_vfsops.c,v 1.47 2017/02/17 08:31:25 hannken Exp $ */
+/* $NetBSD: layer_vfsops.c,v 1.48 2017/03/30 09:16:52 hannken Exp $ */
/*
* Copyright (c) 1999 National Aeronautics & Space Administration
@@ -74,7 +74,7 @@
*/
#include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: layer_vfsops.c,v 1.47 2017/02/17 08:31:25 hannken Exp $");
+__KERNEL_RCSID(0, "$NetBSD: layer_vfsops.c,v 1.48 2017/03/30 09:16:52 hannken Exp $");
#include <sys/param.h>
#include <sys/sysctl.h>
@@ -223,6 +223,9 @@ layerfs_loadvnode(struct mount *mp, stru
mutex_obj_hold(lowervp->v_interlock);
uvm_obj_setlock(&vp->v_uobj, lowervp->v_interlock);
+ /* Share the lock with the lower node. */
+ vshare_lock(vp, lowervp);
+
vp->v_tag = lmp->layerm_tag;
vp->v_type = lowervp->v_type;
vp->v_op = lmp->layerm_vnodeop_p;
Index: src/sys/miscfs/genfs/layer_vnops.c
diff -u src/sys/miscfs/genfs/layer_vnops.c:1.60 src/sys/miscfs/genfs/layer_vnops.c:1.61
--- src/sys/miscfs/genfs/layer_vnops.c:1.60 Fri Jan 27 10:47:13 2017
+++ src/sys/miscfs/genfs/layer_vnops.c Thu Mar 30 09:16:52 2017
@@ -1,4 +1,4 @@
-/* $NetBSD: layer_vnops.c,v 1.60 2017/01/27 10:47:13 hannken Exp $ */
+/* $NetBSD: layer_vnops.c,v 1.61 2017/03/30 09:16:52 hannken Exp $ */
/*
* Copyright (c) 1999 National Aeronautics & Space Administration
@@ -170,7 +170,7 @@
*/
#include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: layer_vnops.c,v 1.60 2017/01/27 10:47:13 hannken Exp $");
+__KERNEL_RCSID(0, "$NetBSD: layer_vnops.c,v 1.61 2017/03/30 09:16:52 hannken Exp $");
#include <sys/param.h>
#include <sys/systm.h>
@@ -743,48 +743,6 @@ layer_reclaim(void *v)
return 0;
}
-int
-layer_lock(void *v)
-{
- struct vop_lock_args /* {
- struct vnode *a_vp;
- int a_flags;
- } */ *ap = v;
- struct vnode *vp = ap->a_vp;
- struct vnode *lowervp = LAYERVPTOLOWERVP(vp);
- int flags = ap->a_flags;
- int error;
-
- if (ISSET(flags, LK_NOWAIT)) {
- error = VOP_LOCK(lowervp, flags);
- if (error)
- return error;
- if (mutex_tryenter(vp->v_interlock)) {
- error = vdead_check(vp, VDEAD_NOWAIT);
- mutex_exit(vp->v_interlock);
- } else
- error = EBUSY;
- if (error)
- VOP_UNLOCK(lowervp);
- return error;
- }
-
- error = VOP_LOCK(lowervp, flags);
- if (error)
- return error;
-
- mutex_enter(vp->v_interlock);
- error = vdead_check(vp, VDEAD_NOWAIT);
- if (error) {
- VOP_UNLOCK(lowervp);
- error = vdead_check(vp, 0);
- KASSERT(error == ENOENT);
- }
- mutex_exit(vp->v_interlock);
-
- return error;
-}
-
/*
* We just feed the returned vnode up to the caller - there's no need
* to build a layer node on top of the node on which we're going to do
Index: src/sys/miscfs/nullfs/null_vnops.c
diff -u src/sys/miscfs/nullfs/null_vnops.c:1.40 src/sys/miscfs/nullfs/null_vnops.c:1.41
--- src/sys/miscfs/nullfs/null_vnops.c:1.40 Fri Jan 27 10:47:13 2017
+++ src/sys/miscfs/nullfs/null_vnops.c Thu Mar 30 09:16:52 2017
@@ -1,4 +1,4 @@
-/* $NetBSD: null_vnops.c,v 1.40 2017/01/27 10:47:13 hannken Exp $ */
+/* $NetBSD: null_vnops.c,v 1.41 2017/03/30 09:16:52 hannken Exp $ */
/*
* Copyright (c) 1999 National Aeronautics & Space Administration
@@ -80,7 +80,7 @@
*/
#include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: null_vnops.c,v 1.40 2017/01/27 10:47:13 hannken Exp $");
+__KERNEL_RCSID(0, "$NetBSD: null_vnops.c,v 1.41 2017/03/30 09:16:52 hannken Exp $");
#include <sys/param.h>
#include <sys/systm.h>
@@ -107,6 +107,8 @@ const struct vnodeopv_entry_desc null_vn
{ &vop_inactive_desc, layer_inactive },
{ &vop_reclaim_desc, layer_reclaim },
{ &vop_lock_desc, layer_lock },
+ { &vop_unlock_desc, layer_unlock },
+ { &vop_islocked_desc, layer_islocked },
{ &vop_print_desc, layer_print },
{ &vop_remove_desc, layer_remove },
{ &vop_rename_desc, layer_rename },
Index: src/sys/miscfs/overlay/overlay_vnops.c
diff -u src/sys/miscfs/overlay/overlay_vnops.c:1.22 src/sys/miscfs/overlay/overlay_vnops.c:1.23
--- src/sys/miscfs/overlay/overlay_vnops.c:1.22 Fri Jan 27 10:47:13 2017
+++ src/sys/miscfs/overlay/overlay_vnops.c Thu Mar 30 09:16:52 2017
@@ -1,4 +1,4 @@
-/* $NetBSD: overlay_vnops.c,v 1.22 2017/01/27 10:47:13 hannken Exp $ */
+/* $NetBSD: overlay_vnops.c,v 1.23 2017/03/30 09:16:52 hannken Exp $ */
/*
* Copyright (c) 1999, 2000 National Aeronautics & Space Administration
@@ -67,7 +67,7 @@
*
* Ancestors:
* @(#)lofs_vnops.c 1.2 (Berkeley) 6/18/92
- * $Id: overlay_vnops.c,v 1.22 2017/01/27 10:47:13 hannken Exp $
+ * $Id: overlay_vnops.c,v 1.23 2017/03/30 09:16:52 hannken Exp $
* ...and...
* @(#)null_vnodeops.c 1.20 92/07/07 UCLA Ficus project
*/
@@ -126,7 +126,7 @@
*/
#include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: overlay_vnops.c,v 1.22 2017/01/27 10:47:13 hannken Exp $");
+__KERNEL_RCSID(0, "$NetBSD: overlay_vnops.c,v 1.23 2017/03/30 09:16:52 hannken Exp $");
#include <sys/param.h>
#include <sys/systm.h>
@@ -155,6 +155,8 @@ const struct vnodeopv_entry_desc overlay
{ &vop_inactive_desc, layer_inactive },
{ &vop_reclaim_desc, layer_reclaim },
{ &vop_lock_desc, layer_lock },
+ { &vop_unlock_desc, layer_unlock },
+ { &vop_islocked_desc, layer_islocked },
{ &vop_print_desc, layer_print },
{ &vop_remove_desc, layer_remove },
{ &vop_rename_desc, layer_rename },
Index: src/sys/miscfs/umapfs/umap_vnops.c
diff -u src/sys/miscfs/umapfs/umap_vnops.c:1.58 src/sys/miscfs/umapfs/umap_vnops.c:1.59
--- src/sys/miscfs/umapfs/umap_vnops.c:1.58 Fri Jan 27 10:47:13 2017
+++ src/sys/miscfs/umapfs/umap_vnops.c Thu Mar 30 09:16:53 2017
@@ -1,4 +1,4 @@
-/* $NetBSD: umap_vnops.c,v 1.58 2017/01/27 10:47:13 hannken Exp $ */
+/* $NetBSD: umap_vnops.c,v 1.59 2017/03/30 09:16:53 hannken Exp $ */
/*
* Copyright (c) 1992, 1993
@@ -39,7 +39,7 @@
*/
#include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: umap_vnops.c,v 1.58 2017/01/27 10:47:13 hannken Exp $");
+__KERNEL_RCSID(0, "$NetBSD: umap_vnops.c,v 1.59 2017/03/30 09:16:53 hannken Exp $");
#include <sys/param.h>
#include <sys/systm.h>
@@ -89,6 +89,8 @@ const struct vnodeopv_entry_desc umap_vn
{ &vop_inactive_desc, layer_inactive },
{ &vop_reclaim_desc, layer_reclaim },
{ &vop_lock_desc, layer_lock },
+ { &vop_unlock_desc, layer_unlock },
+ { &vop_islocked_desc, layer_islocked },
{ &vop_open_desc, layer_open },
{ &vop_close_desc, layer_close },
{ &vop_setattr_desc, layer_setattr },
Index: src/sys/sys/param.h
diff -u src/sys/sys/param.h:1.533 src/sys/sys/param.h:1.534
--- src/sys/sys/param.h:1.533 Tue Mar 14 09:04:16 2017
+++ src/sys/sys/param.h Thu Mar 30 09:16:53 2017
@@ -1,4 +1,4 @@
-/* $NetBSD: param.h,v 1.533 2017/03/14 09:04:16 ozaki-r Exp $ */
+/* $NetBSD: param.h,v 1.534 2017/03/30 09:16:53 hannken Exp $ */
/*-
* Copyright (c) 1982, 1986, 1989, 1993
@@ -67,7 +67,7 @@
* 2.99.9 (299000900)
*/
-#define __NetBSD_Version__ 799006600 /* NetBSD 7.99.66 */
+#define __NetBSD_Version__ 799006700 /* NetBSD 7.99.67 */
#define __NetBSD_Prereq__(M,m,p) (((((M) * 100000000) + \
(m) * 1000000) + (p) * 100) <= __NetBSD_Version__)
Index: src/sys/sys/vnode.h
diff -u src/sys/sys/vnode.h:1.274 src/sys/sys/vnode.h:1.275
--- src/sys/sys/vnode.h:1.274 Fri Feb 17 08:30:00 2017
+++ src/sys/sys/vnode.h Thu Mar 30 09:16:53 2017
@@ -1,4 +1,4 @@
-/* $NetBSD: vnode.h,v 1.274 2017/02/17 08:30:00 hannken Exp $ */
+/* $NetBSD: vnode.h,v 1.275 2017/03/30 09:16:53 hannken Exp $ */
/*-
* Copyright (c) 2008 The NetBSD Foundation, Inc.
@@ -516,6 +516,7 @@ bool vrecycle(struct vnode *);
void vrele(struct vnode *);
void vrele_async(struct vnode *);
void vrele_flush(struct mount *);
+void vshare_lock(vnode_t *, vnode_t *);
int vtruncbuf(struct vnode *, daddr_t, bool, int);
void vwakeup(struct buf *);
int vdead_check(struct vnode *, int);
Index: src/sys/sys/vnode_impl.h
diff -u src/sys/sys/vnode_impl.h:1.12 src/sys/sys/vnode_impl.h:1.13
--- src/sys/sys/vnode_impl.h:1.12 Sat Mar 18 05:55:12 2017
+++ src/sys/sys/vnode_impl.h Thu Mar 30 09:16:53 2017
@@ -1,4 +1,4 @@
-/* $NetBSD: vnode_impl.h,v 1.12 2017/03/18 05:55:12 riastradh Exp $ */
+/* $NetBSD: vnode_impl.h,v 1.13 2017/03/30 09:16:53 hannken Exp $ */
/*-
* Copyright (c) 2016 The NetBSD Foundation, Inc.
@@ -76,7 +76,7 @@ struct vnode_impl {
TAILQ_ENTRY(vnode_impl) vi_synclist; /* s: vnodes with dirty bufs */
TAILQ_ENTRY(vnode_impl) vi_mntvnodes; /* m: vnodes for mount point */
SLIST_ENTRY(vnode_impl) vi_hash; /* c: vnode cache list */
- krwlock_t vi_lock; /* -: lock for this vnode */
+ krwlock_t *vi_lock; /* -: lock for this vnode */
struct vcache_key vi_key; /* c: vnode cache key */
};
typedef struct vnode_impl vnode_impl_t;
