- Change all filesystems and vfs_cache to relock the dvp once the child is

   locked in the ISDOTDOT case.  Se vfs_lookup.c r1.79 for details.

Sponsored by:	Isilon Systems, Inc.

19 files changed, 39 insertions, 64 deletions

diff --git a/sys/coda/coda_vnops.c b/sys/coda/coda_vnops.c
index c8cf74d..a6f6e1a 100644
--- a/sys/coda/coda_vnops.c
+++ b/sys/coda/coda_vnops.c
@@ -1010,6 +1010,7 @@ coda_lookup(struct vop_lookup_args *ap)
 		    return (error);
 		}
 	    }
+	    vn_lock(dvp, LK_RETRY|LK_EXCLUSIVE, td);
 	} else {
 	    /* The parent is locked, and may be the same as the child */
 	    if (*ap->a_vpp && (*ap->a_vpp != dvp)) {
diff --git a/sys/compat/linux/linux_getcwd.c b/sys/compat/linux/linux_getcwd.c
index 1dfe6b4..9b810a3 100644
--- a/sys/compat/linux/linux_getcwd.c
+++ b/sys/compat/linux/linux_getcwd.c
@@ -185,7 +185,7 @@ linux_getcwd_scandir(lvpp, uvpp, bpp, bufp, td)
 
 	/* If we don't care about the pathname, we're done */
 	if (bufp == NULL) {
-		vrele(lvp);
+		vput(lvp);
 		*lvpp = NULL;
 		return 0;
 	}
@@ -281,7 +281,7 @@ unionread:
 	error = ENOENT;
 		
 out:
-	vrele(lvp);
+	vput(lvp);
 	*lvpp = NULL;
 	free(dirbuf, M_TEMP);
 	return error;
diff --git a/sys/fs/cd9660/cd9660_lookup.c b/sys/fs/cd9660/cd9660_lookup.c
index 09dbe5f..b89e670 100644
--- a/sys/fs/cd9660/cd9660_lookup.c
+++ b/sys/fs/cd9660/cd9660_lookup.c
@@ -353,10 +353,9 @@ found:
 					     LK_EXCLUSIVE, &tdp,
 					     dp->i_ino != ino, ep);
 		brelse(bp);
-		if (error) {
-			vn_lock(pdp, LK_EXCLUSIVE | LK_RETRY, td);
+		vn_lock(pdp, LK_EXCLUSIVE | LK_RETRY, td);
+		if (error)
 			return (error);
-		}
 		*vpp = tdp;
 	} else if (dp->i_number == dp->i_ino) {
 		brelse(bp);
diff --git a/sys/fs/coda/coda_vnops.c b/sys/fs/coda/coda_vnops.c
index c8cf74d..a6f6e1a 100644
--- a/sys/fs/coda/coda_vnops.c
+++ b/sys/fs/coda/coda_vnops.c
@@ -1010,6 +1010,7 @@ coda_lookup(struct vop_lookup_args *ap)
 		    return (error);
 		}
 	    }
+	    vn_lock(dvp, LK_RETRY|LK_EXCLUSIVE, td);
 	} else {
 	    /* The parent is locked, and may be the same as the child */
 	    if (*ap->a_vpp && (*ap->a_vpp != dvp)) {
diff --git a/sys/fs/devfs/devfs_vnops.c b/sys/fs/devfs/devfs_vnops.c
index 90139c2..586aa9b 100644
--- a/sys/fs/devfs/devfs_vnops.c
+++ b/sys/fs/devfs/devfs_vnops.c
@@ -618,8 +618,7 @@ devfs_lookupx(ap)
 		de = TAILQ_NEXT(de, de_list);		/* ".." */
 		de = de->de_dir;
 		error = devfs_allocv(de, dvp->v_mount, vpp, td);
-		if (error)
-			vn_lock(dvp, LK_EXCLUSIVE | LK_RETRY, td);
+		vn_lock(dvp, LK_EXCLUSIVE | LK_RETRY, td);
 		return (error);
 	}
 
diff --git a/sys/fs/hpfs/hpfs_vnops.c b/sys/fs/hpfs/hpfs_vnops.c
index a832827..e099fe7 100644
--- a/sys/fs/hpfs/hpfs_vnops.c
+++ b/sys/fs/hpfs/hpfs_vnops.c
@@ -1060,11 +1060,9 @@ hpfs_lookup(ap)
 			VOP_UNLOCK(dvp,0,cnp->cn_thread);
 			error = VFS_VGET(hpmp->hpm_mp,
 				 dhp->h_fn.fn_parent, LK_EXCLUSIVE, ap->a_vpp); 
-			if (error) {
-				vn_lock(dvp, LK_EXCLUSIVE|LK_RETRY,
-				    cnp->cn_thread);
+			vn_lock(dvp, LK_EXCLUSIVE|LK_RETRY, cnp->cn_thread);
+			if (error)
 				return(error);
-			}
 		}
 		return (0);
 	} else {
diff --git a/sys/fs/msdosfs/msdosfs_lookup.c b/sys/fs/msdosfs/msdosfs_lookup.c
index 70ef2b4..5f3e137 100644
--- a/sys/fs/msdosfs/msdosfs_lookup.c
+++ b/sys/fs/msdosfs/msdosfs_lookup.c
@@ -516,10 +516,9 @@ foundroot:
 	if (flags & ISDOTDOT) {
 		VOP_UNLOCK(pdp, 0, td);
 		error = deget(pmp, cluster, blkoff,  &tdp);
-		if (error) {
-			vn_lock(pdp, LK_EXCLUSIVE | LK_RETRY, td); 
+		vn_lock(pdp, LK_EXCLUSIVE | LK_RETRY, td); 
+		if (error)
 			return (error);
-		}
 		*vpp = DETOV(tdp);
 	} else if (dp->de_StartCluster == scn && isadir) {
 		VREF(vdp);	/* we want ourself, ie "." */
diff --git a/sys/fs/nwfs/nwfs_vnops.c b/sys/fs/nwfs/nwfs_vnops.c
index e5780d2..90f9c4e 100644
--- a/sys/fs/nwfs/nwfs_vnops.c
+++ b/sys/fs/nwfs/nwfs_vnops.c
@@ -883,8 +883,7 @@ printf("dvp %d:%d:%d\n", (int)mp, (int)dvp->v_vflag & VV_ROOT, (int)flags & ISDO
 		} else if (flags & ISDOTDOT) {
 			VOP_UNLOCK(dvp, 0, td);	/* unlock parent */
 			error = vget(vp, LK_EXCLUSIVE, td);
-			if (error)
-				vn_lock(dvp, LK_EXCLUSIVE | LK_RETRY, td);
+			vn_lock(dvp, LK_EXCLUSIVE | LK_RETRY, td);
 		} else
 			error = vget(vp, LK_EXCLUSIVE, td);
 		if (!error) {
@@ -901,8 +900,6 @@ printf("dvp %d:%d:%d\n", (int)mp, (int)dvp->v_vflag & VV_ROOT, (int)flags & ISDO
 				vput(vp);
 			else
 				vrele(vp);
-			if (flags & ISDOTDOT)
-				vn_lock(dvp, LK_EXCLUSIVE | LK_RETRY, td);
 		}
 		vdrop(vp);
 		*vpp = NULLVP;
@@ -978,10 +975,9 @@ printf("dvp %d:%d:%d\n", (int)mp, (int)dvp->v_vflag & VV_ROOT, (int)flags & ISDO
 	if (flags & ISDOTDOT) {
 		VOP_UNLOCK(dvp, 0, td);		/* race to get the inode */
 		error = nwfs_nget(mp, fid, NULL, NULL, &vp);
-		if (error) {
-			vn_lock(dvp, LK_EXCLUSIVE | LK_RETRY, td);
+		vn_lock(dvp, LK_EXCLUSIVE | LK_RETRY, td);
+		if (error)
 			return (error);
-		}
 		*vpp = vp;
 	} else if (NWCMPF(&dnp->n_fid, &fid)) {
 		vref(dvp);
diff --git a/sys/fs/pseudofs/pseudofs_vnops.c b/sys/fs/pseudofs/pseudofs_vnops.c
index 3617cdc..dfae1ef 100644
--- a/sys/fs/pseudofs/pseudofs_vnops.c
+++ b/sys/fs/pseudofs/pseudofs_vnops.c
@@ -413,6 +413,8 @@ pfs_lookup(struct vop_cachedlookup_args *va)
 	if (error)
 		goto failed;
 
+	if (cnp->cn_flags & ISDOTDOT)
+		vn_lock(vn, LK_EXCLUSIVE|LK_RETRY, cnp->cn_thread);
 	if (cnp->cn_flags & MAKEENTRY)
 		cache_enter(vn, *vpp, cnp);
 	PFS_RETURN (0);
diff --git a/sys/fs/smbfs/smbfs_vnops.c b/sys/fs/smbfs/smbfs_vnops.c
index 268e5f8..d741c06 100644
--- a/sys/fs/smbfs/smbfs_vnops.c
+++ b/sys/fs/smbfs/smbfs_vnops.c
@@ -1155,9 +1155,6 @@ smbfs_lookup(ap)
 			vput(vp);
 		else
 			vrele(vp);
-		if (flags & ISDOTDOT)
-			if (vn_lock(dvp, LK_EXCLUSIVE, td))
-				panic("smbfs_lookup: Can't relock directory.");
 		*vpp = NULLVP;
 	}
 	/* 
@@ -1229,10 +1226,9 @@ smbfs_lookup(ap)
 	if (flags & ISDOTDOT) {
 		VOP_UNLOCK(dvp, 0, td);
 		error = smbfs_nget(mp, dvp, name, nmlen, NULL, &vp);
-		if (error) {
-			vn_lock(dvp, LK_EXCLUSIVE | LK_RETRY, td);
+		vn_lock(dvp, LK_EXCLUSIVE | LK_RETRY, td);
+		if (error)
 			return error;
-		}
 		*vpp = vp;
 	} else if (isdot) {
 		vref(dvp);
diff --git a/sys/fs/udf/udf_vnops.c b/sys/fs/udf/udf_vnops.c
index c7ff99a..b67bba4 100644
--- a/sys/fs/udf/udf_vnops.c
+++ b/sys/fs/udf/udf_vnops.c
@@ -914,6 +914,7 @@ lookloop:
 		if (flags & ISDOTDOT)
 			VOP_UNLOCK(dvp, 0, a->a_cnp->cn_thread);
 		error = udf_vget(udfmp->im_mountp, id, LK_EXCLUSIVE, &tdp);
+		vn_lock(dvp, LK_EXCLUSIVE|LK_RETRY, a->a_cnp->cn_thread);
 		if (!error) {
 			/*
 			 * Remember where this entry was if it's the final
@@ -927,9 +928,7 @@ lookloop:
 			/* Put this entry in the cache */
 			if (flags & MAKEENTRY)
 				cache_enter(dvp, *vpp, a->a_cnp);
-		} else if (flags & ISDOTDOT)
-			vn_lock(dvp, LK_EXCLUSIVE|LK_RETRY,
-			    a->a_cnp->cn_thread);
+		}
 	} else {
 		/* Name wasn't found on this pass.  Do another pass? */
 		if (numdirpasses == 2) {
diff --git a/sys/fs/unionfs/union_vnops.c b/sys/fs/unionfs/union_vnops.c
index ae80503..061696a 100644
--- a/sys/fs/unionfs/union_vnops.c
+++ b/sys/fs/unionfs/union_vnops.c
@@ -226,19 +226,8 @@ union_lookup1(udvp, pdvp, vpp, cnp)
 		*vpp = NULL;
 		return (error);
 	}
-
-	/*
-	 * The parent directory will have been unlocked, unless this is a
-	 * dotdot lookup or if dvp == tdvp (tdvp must be locked).
-	 *
-	 * We want our dvp to remain locked and ref'd.  We also want tdvp
-	 * to remain locked and ref'd.
-	 */
 	UDEBUG(("parentdir %p result %p flag %lx\n", dvp, tdvp, cnp->cn_flags));
 
-	if (dvp != tdvp && (cnp->cn_flags & ISDOTDOT))
-		vn_lock(dvp, LK_EXCLUSIVE | LK_RETRY, td);
-
 	/*
 	 * Lastly check if the current node is a mount point in
 	 * which case walk up the mount hierarchy making sure not to
diff --git a/sys/gnu/ext2fs/ext2_lookup.c b/sys/gnu/ext2fs/ext2_lookup.c
index 2b3481a..0179f97 100644
--- a/sys/gnu/ext2fs/ext2_lookup.c
+++ b/sys/gnu/ext2fs/ext2_lookup.c
@@ -656,11 +656,10 @@ found:
 	pdp = vdp;
 	if (flags & ISDOTDOT) {
 		VOP_UNLOCK(pdp, 0, td);	/* race to get the inode */
-		if ((error = VFS_VGET(vdp->v_mount, dp->i_ino, LK_EXCLUSIVE,
-		    &tdp)) != 0) {
-			vn_lock(pdp, LK_EXCLUSIVE | LK_RETRY, td);
+		error = VFS_VGET(vdp->v_mount, dp->i_ino, LK_EXCLUSIVE, &tdp);
+		vn_lock(pdp, LK_EXCLUSIVE | LK_RETRY, td);
+		if (error != 0)
 			return (error);
-		}
 		*vpp = tdp;
 	} else if (dp->i_number == dp->i_ino) {
 		VREF(vdp);	/* we want ourself, ie "." */
diff --git a/sys/gnu/fs/ext2fs/ext2_lookup.c b/sys/gnu/fs/ext2fs/ext2_lookup.c
index 2b3481a..0179f97 100644
--- a/sys/gnu/fs/ext2fs/ext2_lookup.c
+++ b/sys/gnu/fs/ext2fs/ext2_lookup.c
@@ -656,11 +656,10 @@ found:
 	pdp = vdp;
 	if (flags & ISDOTDOT) {
 		VOP_UNLOCK(pdp, 0, td);	/* race to get the inode */
-		if ((error = VFS_VGET(vdp->v_mount, dp->i_ino, LK_EXCLUSIVE,
-		    &tdp)) != 0) {
-			vn_lock(pdp, LK_EXCLUSIVE | LK_RETRY, td);
+		error = VFS_VGET(vdp->v_mount, dp->i_ino, LK_EXCLUSIVE, &tdp);
+		vn_lock(pdp, LK_EXCLUSIVE | LK_RETRY, td);
+		if (error != 0)
 			return (error);
-		}
 		*vpp = tdp;
 	} else if (dp->i_number == dp->i_ino) {
 		VREF(vdp);	/* we want ourself, ie "." */
diff --git a/sys/isofs/cd9660/cd9660_lookup.c b/sys/isofs/cd9660/cd9660_lookup.c
index 09dbe5f..b89e670 100644
--- a/sys/isofs/cd9660/cd9660_lookup.c
+++ b/sys/isofs/cd9660/cd9660_lookup.c
@@ -353,10 +353,9 @@ found:
 					     LK_EXCLUSIVE, &tdp,
 					     dp->i_ino != ino, ep);
 		brelse(bp);
-		if (error) {
-			vn_lock(pdp, LK_EXCLUSIVE | LK_RETRY, td);
+		vn_lock(pdp, LK_EXCLUSIVE | LK_RETRY, td);
+		if (error)
 			return (error);
-		}
 		*vpp = tdp;
 	} else if (dp->i_number == dp->i_ino) {
 		brelse(bp);
diff --git a/sys/kern/vfs_cache.c b/sys/kern/vfs_cache.c
index f911a21..88e32de 100644
--- a/sys/kern/vfs_cache.c
+++ b/sys/kern/vfs_cache.c
@@ -344,6 +344,7 @@ cache_lookup(dvp, vpp, cnp)
 {
 	struct namecache *ncp;
 	u_int32_t hash;
+	int error;
 
 	if (!doingcache) {
 		cnp->cn_flags &= ~MAKEENTRY;
@@ -447,9 +448,10 @@ success:
 		VOP_UNLOCK(dvp, 0, cnp->cn_thread);
 	VI_LOCK(*vpp);
 	CACHE_UNLOCK();
-	if (vget(*vpp, cnp->cn_lkflags | LK_INTERLOCK, cnp->cn_thread)) {
-		if (cnp->cn_flags & ISDOTDOT)
-			vn_lock(dvp, LK_EXCLUSIVE | LK_RETRY, cnp->cn_thread);
+	error = vget(*vpp, cnp->cn_lkflags | LK_INTERLOCK, cnp->cn_thread);
+	if (cnp->cn_flags & ISDOTDOT)
+		vn_lock(dvp, LK_EXCLUSIVE | LK_RETRY, cnp->cn_thread);
+	if (error) {
 		*vpp = NULL;
 		goto retry;
 	}
diff --git a/sys/nfs4client/nfs4_vnops.c b/sys/nfs4client/nfs4_vnops.c
index 50947e0..8a45857 100644
--- a/sys/nfs4client/nfs4_vnops.c
+++ b/sys/nfs4client/nfs4_vnops.c
@@ -1050,10 +1050,9 @@ nfs4_lookup(struct vop_lookup_args *ap)
 		VOP_UNLOCK(dvp, 0, td);
 
 		error = nfs_nget(dvp->v_mount, fhp, fhsize, &np);
-		if (error) {
-			vn_lock(dvp, LK_EXCLUSIVE | LK_RETRY, td);
+		vn_lock(dvp, LK_EXCLUSIVE | LK_RETRY, td);
+		if (error)
 			return (error);
-		}
 		newvp = NFSTOV(np);
 
 		nfs4_vnop_loadattrcache(newvp, &ga.fa, NULL);
diff --git a/sys/nfsclient/nfs_vnops.c b/sys/nfsclient/nfs_vnops.c
index 0b5109a..8eba072 100644
--- a/sys/nfsclient/nfs_vnops.c
+++ b/sys/nfsclient/nfs_vnops.c
@@ -860,10 +860,9 @@ nfs_lookup(struct vop_lookup_args *ap)
 	if (flags & ISDOTDOT) {
 		VOP_UNLOCK(dvp, 0, td);
 		error = nfs_nget(dvp->v_mount, fhp, fhsize, &np);
-		if (error) {
-			vn_lock(dvp, LK_EXCLUSIVE | LK_RETRY, td);
+		vn_lock(dvp, LK_EXCLUSIVE | LK_RETRY, td);
+		if (error)
 			return (error);
-		}
 		newvp = NFSTOV(np);
 	} else if (NFS_CMPFH(np, fhp, fhsize)) {
 		VREF(dvp);
diff --git a/sys/ufs/ufs/ufs_lookup.c b/sys/ufs/ufs/ufs_lookup.c
index 1efeac4..e4332c1 100644
--- a/sys/ufs/ufs/ufs_lookup.c
+++ b/sys/ufs/ufs/ufs_lookup.c
@@ -560,10 +560,9 @@ found:
 		VOP_UNLOCK(pdp, 0, td);	/* race to get the inode */
 		error = VFS_VGET(pdp->v_mount, dp->i_ino,
 		    cnp->cn_lkflags, &tdp);
-		if (error) {
-			vn_lock(pdp, LK_EXCLUSIVE | LK_RETRY, td);
+		vn_lock(pdp, LK_EXCLUSIVE | LK_RETRY, td);
+		if (error)
 			return (error);
-		}
 		*vpp = tdp;
 	} else if (dp->i_number == dp->i_ino) {
 		VREF(vdp);	/* we want ourself, ie "." */