Author: daichi
Date: Thu May 10 20:37:56 2012
New Revision: 235244
URL: http://svn.freebsd.org/changeset/base/235244
Log:
MFC: 234867 and 234944
- fixed a vnode lock hang-up issue.
- fixed an incorrect lock status issue.
- fixed an incorrect lock issue of unionfs root vnode removed.
(pointed out by keith)
- fixed an infinity loop issue.
(pointed out by dumbbell)
- changed to do LK_RELEASE expressly when unlocked.
- fixed a unionfs_readdir math issue
Submitted by: oz...@ongs.co.jp, Matthew Fleming <mflem...@isilon.com>
Modified:
stable/8/sys/fs/unionfs/union_subr.c
stable/8/sys/fs/unionfs/union_vfsops.c
stable/8/sys/fs/unionfs/union_vnops.c
Modified: stable/8/sys/fs/unionfs/union_subr.c
==============================================================================
--- stable/8/sys/fs/unionfs/union_subr.c Thu May 10 20:35:50 2012
(r235243)
+++ stable/8/sys/fs/unionfs/union_subr.c Thu May 10 20:37:56 2012
(r235244)
@@ -2,8 +2,8 @@
* Copyright (c) 1994 Jan-Simon Pendry
* Copyright (c) 1994
* The Regents of the University of California. All rights reserved.
- * Copyright (c) 2005, 2006 Masanori Ozawa <oz...@ongs.co.jp>, ONGS Inc.
- * Copyright (c) 2006 Daichi Goto <dai...@freebsd.org>
+ * Copyright (c) 2005, 2006, 2012 Masanori Ozawa <oz...@ongs.co.jp>, ONGS Inc.
+ * Copyright (c) 2006, 2012 Daichi Goto <dai...@freebsd.org>
*
* This code is derived from software contributed to Berkeley by
* Jan-Simon Pendry.
@@ -350,19 +350,22 @@ unionfs_noderem(struct vnode *vp, struct
uvp = unp->un_uppervp;
dvp = unp->un_dvp;
unp->un_lowervp = unp->un_uppervp = NULLVP;
-
vp->v_vnlock = &(vp->v_lock);
vp->v_data = NULL;
- lockmgr(vp->v_vnlock, LK_EXCLUSIVE | LK_INTERLOCK, VI_MTX(vp));
+ vp->v_object = NULL;
+ VI_UNLOCK(vp);
+
if (lvp != NULLVP)
- VOP_UNLOCK(lvp, 0);
+ VOP_UNLOCK(lvp, LK_RELEASE);
if (uvp != NULLVP)
- VOP_UNLOCK(uvp, 0);
- vp->v_object = NULL;
+ VOP_UNLOCK(uvp, LK_RELEASE);
if (dvp != NULLVP && unp->un_hash.le_prev != NULL)
unionfs_rem_cached_vnode(unp, dvp);
+ if (lockmgr(vp->v_vnlock, LK_EXCLUSIVE, VI_MTX(vp)) != 0)
+ panic("the lock for deletion is unacquirable.");
+
if (lvp != NULLVP) {
vfslocked = VFS_LOCK_GIANT(lvp->v_mount);
vrele(lvp);
@@ -550,7 +553,7 @@ unionfs_relookup(struct vnode *dvp, stru
cn->cn_flags |= (cnp->cn_flags & SAVESTART);
vref(dvp);
- VOP_UNLOCK(dvp, 0);
+ VOP_UNLOCK(dvp, LK_RELEASE);
if ((error = relookup(dvp, vpp, cn))) {
uma_zfree(namei_zone, cn->cn_pnbuf);
@@ -951,7 +954,7 @@ unionfs_vn_create_on_upper(struct vnode
*vpp = vp;
unionfs_vn_create_on_upper_free_out1:
- VOP_UNLOCK(udvp, 0);
+ VOP_UNLOCK(udvp, LK_RELEASE);
unionfs_vn_create_on_upper_free_out2:
if (cn.cn_flags & HASBUF) {
Modified: stable/8/sys/fs/unionfs/union_vfsops.c
==============================================================================
--- stable/8/sys/fs/unionfs/union_vfsops.c Thu May 10 20:35:50 2012
(r235243)
+++ stable/8/sys/fs/unionfs/union_vfsops.c Thu May 10 20:37:56 2012
(r235244)
@@ -1,8 +1,8 @@
/*-
* Copyright (c) 1994, 1995 The Regents of the University of California.
* Copyright (c) 1994, 1995 Jan-Simon Pendry.
- * Copyright (c) 2005, 2006 Masanori Ozawa <oz...@ongs.co.jp>, ONGS Inc.
- * Copyright (c) 2006 Daichi Goto <dai...@freebsd.org>
+ * Copyright (c) 2005, 2006, 2012 Masanori Ozawa <oz...@ongs.co.jp>, ONGS Inc.
+ * Copyright (c) 2006, 2012 Daichi Goto <dai...@freebsd.org>
* All rights reserved.
*
* This code is derived from software donated to Berkeley by
@@ -166,7 +166,7 @@ unionfs_domount(struct mount *mp)
uid = va.va_uid;
gid = va.va_gid;
}
- VOP_UNLOCK(mp->mnt_vnodecovered, 0);
+ VOP_UNLOCK(mp->mnt_vnodecovered, LK_RELEASE);
if (error)
return (error);
@@ -251,7 +251,7 @@ unionfs_domount(struct mount *mp)
* Save reference
*/
if (below) {
- VOP_UNLOCK(upperrootvp, 0);
+ VOP_UNLOCK(upperrootvp, LK_RELEASE);
vn_lock(lowerrootvp, LK_EXCLUSIVE | LK_RETRY);
ump->um_lowervp = upperrootvp;
ump->um_uppervp = lowerrootvp;
@@ -302,7 +302,7 @@ unionfs_domount(struct mount *mp)
/*
* Unlock the node
*/
- VOP_UNLOCK(ump->um_uppervp, 0);
+ VOP_UNLOCK(ump->um_uppervp, LK_RELEASE);
/*
* Get the unionfs root vnode.
Modified: stable/8/sys/fs/unionfs/union_vnops.c
==============================================================================
--- stable/8/sys/fs/unionfs/union_vnops.c Thu May 10 20:35:50 2012
(r235243)
+++ stable/8/sys/fs/unionfs/union_vnops.c Thu May 10 20:37:56 2012
(r235244)
@@ -2,8 +2,8 @@
* Copyright (c) 1992, 1993, 1994, 1995 Jan-Simon Pendry.
* Copyright (c) 1992, 1993, 1994, 1995
* The Regents of the University of California.
- * Copyright (c) 2005, 2006 Masanori Ozawa <oz...@ongs.co.jp>, ONGS Inc.
- * Copyright (c) 2006 Daichi Goto <dai...@freebsd.org>
+ * Copyright (c) 2005, 2006, 2012 Masanori Ozawa <oz...@ongs.co.jp>, ONGS Inc.
+ * Copyright (c) 2006, 2012 Daichi Goto <dai...@freebsd.org>
* All rights reserved.
*
* This code is derived from software contributed to Berkeley by
@@ -75,21 +75,6 @@
KASSERT(((vp)->v_op == &unionfs_vnodeops), \
("unionfs: it is not unionfs-vnode"))
-/* lockmgr lock <-> reverse table */
-struct lk_lr_table {
- int lock;
- int revlock;
-};
-
-static struct lk_lr_table un_llt[] = {
- {LK_SHARED, LK_RELEASE},
- {LK_EXCLUSIVE, LK_RELEASE},
- {LK_UPGRADE, LK_DOWNGRADE},
- {LK_DOWNGRADE, LK_UPGRADE},
- {0, 0}
-};
-
-
static int
unionfs_lookup(struct vop_cachedlookup_args *ap)
{
@@ -141,7 +126,7 @@ unionfs_lookup(struct vop_cachedlookup_a
if (udvp != NULLVP) {
dtmpvp = udvp;
if (ldvp != NULLVP)
- VOP_UNLOCK(ldvp, 0);
+ VOP_UNLOCK(ldvp, LK_RELEASE);
}
else
dtmpvp = ldvp;
@@ -149,7 +134,7 @@ unionfs_lookup(struct vop_cachedlookup_a
error = VOP_LOOKUP(dtmpvp, &vp, cnp);
if (dtmpvp == udvp && ldvp != NULLVP) {
- VOP_UNLOCK(udvp, 0);
+ VOP_UNLOCK(udvp, LK_RELEASE);
vn_lock(dvp, LK_EXCLUSIVE | LK_RETRY);
}
@@ -161,10 +146,10 @@ unionfs_lookup(struct vop_cachedlookup_a
*/
if (nameiop == DELETE || nameiop == RENAME ||
(cnp->cn_lkflags & LK_TYPE_MASK))
- VOP_UNLOCK(vp, 0);
+ VOP_UNLOCK(vp, LK_RELEASE);
vrele(vp);
- VOP_UNLOCK(dvp, 0);
+ VOP_UNLOCK(dvp, LK_RELEASE);
*(ap->a_vpp) = dunp->un_dvp;
vref(dunp->un_dvp);
@@ -202,7 +187,7 @@ unionfs_lookup(struct vop_cachedlookup_a
}
if (nameiop == DELETE || nameiop == RENAME ||
(cnp->cn_lkflags & LK_TYPE_MASK))
- VOP_UNLOCK(uvp, 0);
+ VOP_UNLOCK(uvp, LK_RELEASE);
}
/* check whiteout */
@@ -246,7 +231,7 @@ unionfs_lookup(struct vop_cachedlookup_a
return (lerror);
}
if (cnp->cn_lkflags & LK_TYPE_MASK)
- VOP_UNLOCK(lvp, 0);
+ VOP_UNLOCK(lvp, LK_RELEASE);
}
}
@@ -281,7 +266,7 @@ unionfs_lookup(struct vop_cachedlookup_a
goto unionfs_lookup_out;
if (LK_SHARED == (cnp->cn_lkflags & LK_TYPE_MASK))
- VOP_UNLOCK(vp, 0);
+ VOP_UNLOCK(vp, LK_RELEASE);
if (LK_EXCLUSIVE != VOP_ISLOCKED(vp)) {
vn_lock(vp, LK_EXCLUSIVE | LK_RETRY);
lockflag = 1;
@@ -289,7 +274,7 @@ unionfs_lookup(struct vop_cachedlookup_a
error = unionfs_mkshadowdir(MOUNTTOUNIONFSMOUNT(dvp->v_mount),
udvp, VTOUNIONFS(vp), cnp, td);
if (lockflag != 0)
- VOP_UNLOCK(vp, 0);
+ VOP_UNLOCK(vp, LK_RELEASE);
if (error != 0) {
UNIONFSDEBUG("unionfs_lookup: Unable to create shadow
dir.");
if ((cnp->cn_lkflags & LK_TYPE_MASK) == LK_EXCLUSIVE)
@@ -386,7 +371,7 @@ unionfs_create(struct vop_create_args *a
if (vp->v_type == VSOCK)
*(ap->a_vpp) = vp;
else {
- VOP_UNLOCK(vp, 0);
+ VOP_UNLOCK(vp, LK_RELEASE);
error = unionfs_nodeget(ap->a_dvp->v_mount, vp, NULLVP,
ap->a_dvp, ap->a_vpp, cnp, curthread);
vrele(vp);
@@ -460,7 +445,7 @@ unionfs_mknod(struct vop_mknod_args *ap)
if (vp->v_type == VSOCK)
*(ap->a_vpp) = vp;
else {
- VOP_UNLOCK(vp, 0);
+ VOP_UNLOCK(vp, LK_RELEASE);
error = unionfs_nodeget(ap->a_dvp->v_mount, vp, NULLVP,
ap->a_dvp, ap->a_vpp, cnp, curthread);
vrele(vp);
@@ -564,6 +549,7 @@ unionfs_close(struct vop_close_args *ap)
struct unionfs_node_status *unsp;
struct ucred *cred;
struct thread *td;
+ struct vnode *vp;
struct vnode *ovp;
UNIONFS_INTERNAL_DEBUG("unionfs_close: enter\n");
@@ -571,12 +557,14 @@ unionfs_close(struct vop_close_args *ap)
KASSERT_UNIONFS_VNODE(ap->a_vp);
locked = 0;
- unp = VTOUNIONFS(ap->a_vp);
+ vp = ap->a_vp;
+ unp = VTOUNIONFS(vp);
cred = ap->a_cred;
td = ap->a_td;
- if (VOP_ISLOCKED(ap->a_vp) != LK_EXCLUSIVE) {
- vn_lock(ap->a_vp, LK_EXCLUSIVE | LK_RETRY);
+ if (VOP_ISLOCKED(vp) != LK_EXCLUSIVE) {
+ if (vn_lock(vp, LK_UPGRADE) != 0)
+ vn_lock(vp, LK_EXCLUSIVE | LK_RETRY);
locked = 1;
}
unionfs_get_node_status(unp, td, &unsp);
@@ -599,7 +587,7 @@ unionfs_close(struct vop_close_args *ap)
if (error != 0)
goto unionfs_close_abort;
- ap->a_vp->v_object = ovp->v_object;
+ vp->v_object = ovp->v_object;
if (ovp == unp->un_uppervp) {
unsp->uns_upper_opencnt--;
@@ -610,7 +598,7 @@ unionfs_close(struct vop_close_args *ap)
unsp->uns_lower_opencnt--;
}
if (unsp->uns_lower_opencnt > 0)
- ap->a_vp->v_object = unp->un_lowervp->v_object;
+ vp->v_object = unp->un_lowervp->v_object;
}
} else
unsp->uns_lower_opencnt--;
@@ -619,7 +607,7 @@ unionfs_close_abort:
unionfs_tryrem_node_status(unp, unsp);
if (locked != 0)
- VOP_UNLOCK(ap->a_vp, 0);
+ vn_lock(vp, LK_DOWNGRADE | LK_RETRY);
UNIONFS_INTERNAL_DEBUG("unionfs_close: leave (%d)\n", error);
@@ -914,7 +902,7 @@ unionfs_ioctl(struct vop_ioctl_args *ap)
unionfs_get_node_status(unp, ap->a_td, &unsp);
ovp = (unsp->uns_upper_opencnt ? unp->un_uppervp : unp->un_lowervp);
unionfs_tryrem_node_status(unp, unsp);
- VOP_UNLOCK(ap->a_vp, 0);
+ VOP_UNLOCK(ap->a_vp, LK_RELEASE);
if (ovp == NULLVP)
return (EBADF);
@@ -941,7 +929,7 @@ unionfs_poll(struct vop_poll_args *ap)
unionfs_get_node_status(unp, ap->a_td, &unsp);
ovp = (unsp->uns_upper_opencnt ? unp->un_uppervp : unp->un_lowervp);
unionfs_tryrem_node_status(unp, unsp);
- VOP_UNLOCK(ap->a_vp, 0);
+ VOP_UNLOCK(ap->a_vp, LK_RELEASE);
if (ovp == NULLVP)
return (EBADF);
@@ -1001,7 +989,7 @@ unionfs_remove(struct vop_remove_args *a
ump = NULL;
vp = uvp = lvp = NULLVP;
/* search vnode */
- VOP_UNLOCK(ap->a_vp, 0);
+ VOP_UNLOCK(ap->a_vp, LK_RELEASE);
error = unionfs_relookup(udvp, &vp, cnp, &cn, td,
cnp->cn_nameptr, strlen(cnp->cn_nameptr), DELETE);
if (error != 0 && error != ENOENT) {
@@ -1204,7 +1192,7 @@ unionfs_rename(struct vop_rename_args *a
if ((error = vn_lock(fvp, LK_EXCLUSIVE)) != 0)
goto unionfs_rename_abort;
error = unionfs_copyfile(unp, 1, fcnp->cn_cred, td);
- VOP_UNLOCK(fvp, 0);
+ VOP_UNLOCK(fvp, LK_RELEASE);
if (error != 0)
goto unionfs_rename_abort;
break;
@@ -1212,7 +1200,7 @@ unionfs_rename(struct vop_rename_args *a
if ((error = vn_lock(fvp, LK_EXCLUSIVE)) != 0)
goto unionfs_rename_abort;
error = unionfs_mkshadowdir(ump, rfdvp, unp, fcnp, td);
- VOP_UNLOCK(fvp, 0);
+ VOP_UNLOCK(fvp, LK_RELEASE);
if (error != 0)
goto unionfs_rename_abort;
break;
@@ -1269,13 +1257,13 @@ unionfs_rename(struct vop_rename_args *a
if ((error = vn_lock(fdvp, LK_EXCLUSIVE)) != 0)
goto unionfs_rename_abort;
error = unionfs_relookup_for_delete(fdvp, fcnp, td);
- VOP_UNLOCK(fdvp, 0);
+ VOP_UNLOCK(fdvp, LK_RELEASE);
if (error != 0)
goto unionfs_rename_abort;
/* Locke of tvp is canceled in order to avoid recursive lock. */
if (tvp != NULLVP && tvp != tdvp)
- VOP_UNLOCK(tvp, 0);
+ VOP_UNLOCK(tvp, LK_RELEASE);
error = unionfs_relookup_for_rename(tdvp, tcnp, td);
if (tvp != NULLVP && tvp != tdvp)
vn_lock(tvp, LK_EXCLUSIVE | LK_RETRY);
@@ -1293,11 +1281,11 @@ unionfs_rename(struct vop_rename_args *a
}
if (ltdvp != NULLVP)
- VOP_UNLOCK(ltdvp, 0);
+ VOP_UNLOCK(ltdvp, LK_RELEASE);
if (tdvp != rtdvp)
vrele(tdvp);
if (ltvp != NULLVP)
- VOP_UNLOCK(ltvp, 0);
+ VOP_UNLOCK(ltvp, LK_RELEASE);
if (tvp != rtvp && tvp != NULLVP) {
if (rtvp == NULLVP)
vput(tvp);
@@ -1371,7 +1359,7 @@ unionfs_mkdir(struct vop_mkdir_args *ap)
}
if ((error = VOP_MKDIR(udvp, &uvp, cnp, ap->a_vap)) == 0) {
- VOP_UNLOCK(uvp, 0);
+ VOP_UNLOCK(uvp, LK_RELEASE);
cnp->cn_lkflags = LK_EXCLUSIVE;
error = unionfs_nodeget(ap->a_dvp->v_mount, uvp, NULLVP,
ap->a_dvp, ap->a_vpp, cnp, td);
@@ -1427,7 +1415,9 @@ unionfs_rmdir(struct vop_rmdir_args *ap)
ump = MOUNTTOUNIONFSMOUNT(ap->a_vp->v_mount);
if (ump->um_whitemode == UNIONFS_WHITE_ALWAYS || lvp != NULLVP)
cnp->cn_flags |= DOWHITEOUT;
- error = VOP_RMDIR(udvp, uvp, cnp);
+ error = unionfs_relookup_for_delete(ap->a_dvp, cnp, td);
+ if (!error)
+ error = VOP_RMDIR(udvp, uvp, cnp);
}
else if (lvp != NULLVP)
error = unionfs_mkwhiteout(udvp, cnp, td, unp->un_path);
@@ -1467,7 +1457,7 @@ unionfs_symlink(struct vop_symlink_args
if (udvp != NULLVP) {
error = VOP_SYMLINK(udvp, &uvp, cnp, ap->a_vap, ap->a_target);
if (error == 0) {
- VOP_UNLOCK(uvp, 0);
+ VOP_UNLOCK(uvp, LK_RELEASE);
cnp->cn_lkflags = LK_EXCLUSIVE;
error = unionfs_nodeget(ap->a_dvp->v_mount, uvp, NULLVP,
ap->a_dvp, ap->a_vpp, cnp, td);
@@ -1487,9 +1477,11 @@ unionfs_readdir(struct vop_readdir_args
int error;
int eofflag;
int locked;
+ int uio_offset_bk;
struct unionfs_node *unp;
struct unionfs_node_status *unsp;
struct uio *uio;
+ struct vnode *vp;
struct vnode *uvp;
struct vnode *lvp;
struct thread *td;
@@ -1505,41 +1497,50 @@ unionfs_readdir(struct vop_readdir_args
error = 0;
eofflag = 0;
locked = 0;
- unp = VTOUNIONFS(ap->a_vp);
+ uio_offset_bk = 0;
uio = ap->a_uio;
- uvp = unp->un_uppervp;
- lvp = unp->un_lowervp;
+ uvp = NULLVP;
+ lvp = NULLVP;
td = uio->uio_td;
ncookies_bk = 0;
cookies_bk = NULL;
- if (ap->a_vp->v_type != VDIR)
+ vp = ap->a_vp;
+ if (vp->v_type != VDIR)
return (ENOTDIR);
- /* check opaque */
- if (uvp != NULLVP && lvp != NULLVP) {
- if ((error = VOP_GETATTR(uvp, &va, ap->a_cred)) != 0)
- goto unionfs_readdir_exit;
- if (va.va_flags & OPAQUE)
- lvp = NULLVP;
- }
-
/* check the open count. unionfs needs to open before readdir. */
- if (VOP_ISLOCKED(ap->a_vp) != LK_EXCLUSIVE) {
- vn_lock(ap->a_vp, LK_UPGRADE | LK_RETRY);
+ if (VOP_ISLOCKED(vp) != LK_EXCLUSIVE) {
+ if (vn_lock(vp, LK_UPGRADE) != 0)
+ vn_lock(vp, LK_EXCLUSIVE | LK_RETRY);
locked = 1;
}
- unionfs_get_node_status(unp, td, &unsp);
- if ((uvp != NULLVP && unsp->uns_upper_opencnt <= 0) ||
- (lvp != NULLVP && unsp->uns_lower_opencnt <= 0)) {
- unionfs_tryrem_node_status(unp, unsp);
+ unp = VTOUNIONFS(vp);
+ if (unp == NULL)
error = EBADF;
+ else {
+ uvp = unp->un_uppervp;
+ lvp = unp->un_lowervp;
+ unionfs_get_node_status(unp, td, &unsp);
+ if ((uvp != NULLVP && unsp->uns_upper_opencnt <= 0) ||
+ (lvp != NULLVP && unsp->uns_lower_opencnt <= 0)) {
+ unionfs_tryrem_node_status(unp, unsp);
+ error = EBADF;
+ }
}
- if (locked == 1)
- vn_lock(ap->a_vp, LK_DOWNGRADE | LK_RETRY);
+ if (locked)
+ vn_lock(vp, LK_DOWNGRADE | LK_RETRY);
if (error != 0)
goto unionfs_readdir_exit;
+ /* check opaque */
+ if (uvp != NULLVP && lvp != NULLVP) {
+ if ((error = VOP_GETATTR(uvp, &va, ap->a_cred)) != 0)
+ goto unionfs_readdir_exit;
+ if (va.va_flags & OPAQUE)
+ lvp = NULLVP;
+ }
+
/* upper only */
if (uvp != NULLVP && lvp == NULLVP) {
error = VOP_READDIR(uvp, uio, ap->a_cred, ap->a_eofflag,
@@ -1576,7 +1577,7 @@ unionfs_readdir(struct vop_readdir_args
unsp->uns_readdir_status = 1;
/*
- * ufs(and other fs) needs size of uio_resid larger than
+ * UFS(and other FS) needs size of uio_resid larger than
* DIRBLKSIZ.
* size of DIRBLKSIZ equals DEV_BSIZE.
* (see: ufs/ufs/ufs_vnops.c ufs_readdir func , ufs/ufs/dir.h)
@@ -1585,7 +1586,7 @@ unionfs_readdir(struct vop_readdir_args
goto unionfs_readdir_exit;
/*
- * backup cookies
+ * Backup cookies.
* It prepares to readdir in lower.
*/
if (ap->a_ncookies != NULL) {
@@ -1601,6 +1602,11 @@ unionfs_readdir(struct vop_readdir_args
/* initialize for readdir in lower */
if (unsp->uns_readdir_status == 1) {
unsp->uns_readdir_status = 2;
+ /*
+ * Backup uio_offset. See the comment after the
+ * VOP_READDIR call on the lower layer.
+ */
+ uio_offset_bk = uio->uio_offset;
uio->uio_offset = 0;
}
@@ -1612,6 +1618,19 @@ unionfs_readdir(struct vop_readdir_args
error = VOP_READDIR(lvp, uio, ap->a_cred, ap->a_eofflag,
ap->a_ncookies, ap->a_cookies);
+ /*
+ * We can't return an uio_offset of 0: this would trigger an
+ * infinite loop, because the next call to unionfs_readdir would
+ * always restart with the upper layer (uio_offset == 0) and
+ * always return some data.
+ *
+ * This happens when the lower layer root directory is removed.
+ * (A root directory deleting of unionfs should not be permitted.
+ * But current VFS can not do it.)
+ */
+ if (uio->uio_offset == 0)
+ uio->uio_offset = uio_offset_bk;
+
if (cookies_bk != NULL) {
/* merge cookies */
int size;
@@ -1623,7 +1642,7 @@ unionfs_readdir(struct vop_readdir_args
pos = newcookies;
memcpy(pos, cookies_bk, ncookies_bk * sizeof(u_long));
- pos += ncookies_bk * sizeof(u_long);
+ pos += ncookies_bk;
memcpy(pos, *(ap->a_cookies), *(ap->a_ncookies) *
sizeof(u_long));
free(cookies_bk, M_TEMP);
free(*(ap->a_cookies), M_TEMP);
@@ -1743,18 +1762,66 @@ unionfs_print(struct vop_print_args *ap)
}
static int
-unionfs_get_llt_revlock(int flags)
+unionfs_islocked(struct vop_islocked_args *ap)
{
- int count;
+ struct unionfs_node *unp;
- flags &= LK_TYPE_MASK;
- for (count = 0; un_llt[count].lock != 0; count++) {
- if (flags == un_llt[count].lock) {
- return un_llt[count].revlock;
- }
+ KASSERT_UNIONFS_VNODE(ap->a_vp);
+
+ unp = VTOUNIONFS(ap->a_vp);
+ if (unp == NULL)
+ return (vop_stdislocked(ap));
+
+ if (unp->un_uppervp != NULLVP)
+ return (VOP_ISLOCKED(unp->un_uppervp));
+ if (unp->un_lowervp != NULLVP)
+ return (VOP_ISLOCKED(unp->un_lowervp));
+ return (vop_stdislocked(ap));
+}
+
+static int
+unionfs_get_llt_revlock(struct vnode *vp, int flags)
+{
+ int revlock;
+
+ revlock = 0;
+
+ switch (flags & LK_TYPE_MASK) {
+ case LK_SHARED:
+ if (VOP_ISLOCKED(vp) == LK_EXCLUSIVE)
+ revlock = LK_UPGRADE;
+ else
+ revlock = LK_RELEASE;
+ break;
+ case LK_EXCLUSIVE:
+ case LK_UPGRADE:
+ revlock = LK_RELEASE;
+ break;
+ case LK_DOWNGRADE:
+ revlock = LK_UPGRADE;
+ break;
+ default:
+ break;
}
- return 0;
+ return (revlock);
+}
+
+/*
+ * The state of an acquired lock is adjusted similarly to
+ * the time of error generating.
+ * flags: LK_RELEASE or LK_UPGRADE
+ */
+static void
+unionfs_revlock(struct vnode *vp, int flags)
+{
+ if (flags & LK_RELEASE)
+ VOP_UNLOCK(vp, flags);
+ else {
+ /* UPGRADE */
+ if (vn_lock(vp, flags) != 0)
+ vn_lock(vp, LK_EXCLUSIVE | LK_RETRY);
+ }
}
static int
@@ -1763,6 +1830,7 @@ unionfs_lock(struct vop_lock1_args *ap)
int error;
int flags;
int revlock;
+ int interlock;
int uhold;
struct mount *mp;
struct unionfs_mount *ump;
@@ -1774,15 +1842,13 @@ unionfs_lock(struct vop_lock1_args *ap)
KASSERT_UNIONFS_VNODE(ap->a_vp);
error = 0;
+ interlock = 1;
uhold = 0;
flags = ap->a_flags;
vp = ap->a_vp;
if (LK_RELEASE == (flags & LK_TYPE_MASK) || !(flags & LK_TYPE_MASK))
- return (VOP_UNLOCK(vp, flags));
-
- if ((revlock = unionfs_get_llt_revlock(flags)) == 0)
- panic("unknown lock type: 0x%x", flags & LK_TYPE_MASK);
+ return (VOP_UNLOCK(vp, flags | LK_RELEASE));
if ((flags & LK_INTERLOCK) == 0)
VI_LOCK(vp);
@@ -1798,6 +1864,9 @@ unionfs_lock(struct vop_lock1_args *ap)
lvp = unp->un_lowervp;
uvp = unp->un_uppervp;
+ if ((revlock = unionfs_get_llt_revlock(vp, flags)) == 0)
+ panic("unknown lock type: 0x%x", flags & LK_TYPE_MASK);
+
if ((mp->mnt_kern_flag & MNTK_MPSAFE) != 0 &&
(vp->v_iflag & VI_OWEINACT) != 0)
flags |= LK_NOWAIT;
@@ -1811,6 +1880,23 @@ unionfs_lock(struct vop_lock1_args *ap)
flags |= LK_CANRECURSE;
if (lvp != NULLVP) {
+ if (uvp != NULLVP && flags & LK_UPGRADE) {
+ /* Share Lock is once released and a deadlock is
avoided. */
+ VI_LOCK_FLAGS(uvp, MTX_DUPOK);
+ vholdl(uvp);
+ uhold = 1;
+ VI_UNLOCK(vp);
+ VOP_UNLOCK(uvp, LK_RELEASE | LK_INTERLOCK);
+ VI_LOCK(vp);
+ unp = VTOUNIONFS(vp);
+ if (unp == NULL) {
+ /* vnode is released. */
+ VI_UNLOCK(vp);
+ VOP_UNLOCK(lvp, LK_RELEASE);
+ vdrop(uvp);
+ return (EBUSY);
+ }
+ }
VI_LOCK_FLAGS(lvp, MTX_DUPOK);
flags |= LK_INTERLOCK;
vholdl(lvp);
@@ -1823,19 +1909,28 @@ unionfs_lock(struct vop_lock1_args *ap)
VI_LOCK(vp);
unp = VTOUNIONFS(vp);
if (unp == NULL) {
+ /* vnode is released. */
VI_UNLOCK(vp);
if (error == 0)
- VOP_UNLOCK(lvp, 0);
+ VOP_UNLOCK(lvp, LK_RELEASE);
vdrop(lvp);
+ if (uhold != 0)
+ vdrop(uvp);
return (vop_stdlock(ap));
}
}
if (error == 0 && uvp != NULLVP) {
+ if (uhold && flags & LK_UPGRADE) {
+ flags &= ~LK_TYPE_MASK;
+ flags |= LK_EXCLUSIVE;
+ }
VI_LOCK_FLAGS(uvp, MTX_DUPOK);
flags |= LK_INTERLOCK;
- vholdl(uvp);
- uhold = 1;
+ if (uhold == 0) {
+ vholdl(uvp);
+ uhold = 1;
+ }
VI_UNLOCK(vp);
ap->a_flags &= ~LK_INTERLOCK;
@@ -1845,30 +1940,27 @@ unionfs_lock(struct vop_lock1_args *ap)
VI_LOCK(vp);
unp = VTOUNIONFS(vp);
if (unp == NULL) {
+ /* vnode is released. */
VI_UNLOCK(vp);
- if (error == 0) {
- VOP_UNLOCK(uvp, 0);
- if (lvp != NULLVP)
- VOP_UNLOCK(lvp, 0);
- }
- if (lvp != NULLVP)
- vdrop(lvp);
+ if (error == 0)
+ VOP_UNLOCK(uvp, LK_RELEASE);
vdrop(uvp);
+ if (lvp != NULLVP) {
+ VOP_UNLOCK(lvp, LK_RELEASE);
+ vdrop(lvp);
+ }
return (vop_stdlock(ap));
}
-
if (error != 0 && lvp != NULLVP) {
+ /* rollback */
VI_UNLOCK(vp);
- if ((revlock & LK_TYPE_MASK) == LK_RELEASE)
- VOP_UNLOCK(lvp, revlock);
- else
- vn_lock(lvp, revlock | LK_RETRY);
- goto unionfs_lock_abort;
+ unionfs_revlock(lvp, revlock);
+ interlock = 0;
}
}
- VI_UNLOCK(vp);
-unionfs_lock_abort:
+ if (interlock)
+ VI_UNLOCK(vp);
if (lvp != NULLVP)
vdrop(lvp);
if (uhold != 0)
@@ -2013,7 +2105,7 @@ unionfs_advlock(struct vop_advlock_args
unionfs_tryrem_node_status(unp, unsp);
}
- VOP_UNLOCK(vp, 0);
+ VOP_UNLOCK(vp, LK_RELEASE);
error = VOP_ADVLOCK(uvp, ap->a_id, ap->a_op, ap->a_fl, ap->a_flags);
@@ -2022,7 +2114,7 @@ unionfs_advlock(struct vop_advlock_args
return error;
unionfs_advlock_abort:
- VOP_UNLOCK(vp, 0);
+ VOP_UNLOCK(vp, LK_RELEASE);
UNIONFS_INTERNAL_DEBUG("unionfs_advlock: leave (%d)\n", error);
@@ -2150,7 +2242,8 @@ unionfs_openextattr(struct vop_openextat
error = VOP_OPENEXTATTR(tvp, ap->a_cred, ap->a_td);
if (error == 0) {
- vn_lock(vp, LK_UPGRADE | LK_RETRY);
+ if (vn_lock(vp, LK_UPGRADE) != 0)
+ vn_lock(vp, LK_EXCLUSIVE | LK_RETRY);
if (tvp == unp->un_uppervp)
unp->un_flag |= UNIONFS_OPENEXTU;
else
@@ -2186,7 +2279,8 @@ unionfs_closeextattr(struct vop_closeext
error = VOP_CLOSEEXTATTR(tvp, ap->a_commit, ap->a_cred, ap->a_td);
if (error == 0) {
- vn_lock(vp, LK_UPGRADE | LK_RETRY);
+ if (vn_lock(vp, LK_UPGRADE) != 0)
+ vn_lock(vp, LK_EXCLUSIVE | LK_RETRY);
if (tvp == unp->un_uppervp)
unp->un_flag &= ~UNIONFS_OPENEXTU;
else
@@ -2435,6 +2529,7 @@ struct vop_vector unionfs_vnodeops = {
.vop_getextattr = unionfs_getextattr,
.vop_getwritemount = unionfs_getwritemount,
.vop_inactive = unionfs_inactive,
+ .vop_islocked = unionfs_islocked,
.vop_ioctl = unionfs_ioctl,
.vop_link = unionfs_link,
.vop_listextattr = unionfs_listextattr,
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