Merge branches 'work.namei', 'work.dcache' and 'work.iov_iter' into for-linus

drivers/bluetooth/hci_vhci.c

@@ -181,7 +181,7 @@ static inline ssize_t vhci_get_user(struct vhci_data *data,
 	if (!skb)
 		return -ENOMEM;
 
-	if (copy_from_iter(skb_put(skb, len), len, from) != len) {
+	if (!copy_from_iter_full(skb_put(skb, len), len, from)) {
 		kfree_skb(skb);
 		return -EFAULT;
 	}

drivers/net/macvtap.c

@@ -673,7 +673,6 @@ static ssize_t macvtap_get_user(struct macvtap_queue *q, struct msghdr *m,
 	int depth;
 	bool zerocopy = false;
 	size_t linear;
-	ssize_t n;
 
 	if (q->flags & IFF_VNET_HDR) {
 		vnet_hdr_len = q->vnet_hdr_sz;
@@ -684,8 +683,7 @@ static ssize_t macvtap_get_user(struct macvtap_queue *q, struct msghdr *m,
 		len -= vnet_hdr_len;
 
 		err = -EFAULT;
-		n = copy_from_iter(&vnet_hdr, sizeof(vnet_hdr), from);
-		if (n != sizeof(vnet_hdr))
+		if (!copy_from_iter_full(&vnet_hdr, sizeof(vnet_hdr), from))
 			goto err;
 		iov_iter_advance(from, vnet_hdr_len - sizeof(vnet_hdr));
 		if ((vnet_hdr.flags & VIRTIO_NET_HDR_F_NEEDS_CSUM) &&

drivers/net/tun.c

@@ -1171,7 +1171,6 @@ static ssize_t tun_get_user(struct tun_struct *tun, struct tun_file *tfile,
 	bool zerocopy = false;
 	int err;
 	u32 rxhash;
-	ssize_t n;
 
 	if (!(tun->dev->flags & IFF_UP))
 		return -EIO;
@@ -1181,8 +1180,7 @@ static ssize_t tun_get_user(struct tun_struct *tun, struct tun_file *tfile,
 			return -EINVAL;
 		len -= sizeof(pi);
 
-		n = copy_from_iter(&pi, sizeof(pi), from);
-		if (n != sizeof(pi))
+		if (!copy_from_iter_full(&pi, sizeof(pi), from))
 			return -EFAULT;
 	}
 
@@ -1191,8 +1189,7 @@ static ssize_t tun_get_user(struct tun_struct *tun, struct tun_file *tfile,
 			return -EINVAL;
 		len -= tun->vnet_hdr_sz;
 
-		n = copy_from_iter(&gso, sizeof(gso), from);
-		if (n != sizeof(gso))
+		if (!copy_from_iter_full(&gso, sizeof(gso), from))
 			return -EFAULT;
 
 		if ((gso.flags & VIRTIO_NET_HDR_F_NEEDS_CSUM) &&

drivers/staging/lustre/lustre/llite/dcache.c

@@ -57,9 +57,6 @@ static void ll_release(struct dentry *de)
 
 	LASSERT(de);
 	lld = ll_d2d(de);
-	if (!lld) /* NFS copies the de->d_op methods (bug 4655) */
-		return;
-
 	if (lld->lld_it) {
 		ll_intent_release(lld->lld_it);
 		kfree(lld->lld_it);
@@ -126,30 +123,13 @@ static int ll_ddelete(const struct dentry *de)
 	return 0;
 }
 
-int ll_d_init(struct dentry *de)
+static int ll_d_init(struct dentry *de)
 {
-	CDEBUG(D_DENTRY, "ldd on dentry %pd (%p) parent %p inode %p refc %d\n",
-	       de, de, de->d_parent, d_inode(de), d_count(de));
-
-	if (!de->d_fsdata) {
-		struct ll_dentry_data *lld;
-
-		lld = kzalloc(sizeof(*lld), GFP_NOFS);
-		if (likely(lld)) {
-			spin_lock(&de->d_lock);
-			if (likely(!de->d_fsdata)) {
-				de->d_fsdata = lld;
-				__d_lustre_invalidate(de);
-			} else {
-				kfree(lld);
-			}
-			spin_unlock(&de->d_lock);
-		} else {
-			return -ENOMEM;
-		}
-	}
-	LASSERT(de->d_op == &ll_d_ops);
-
+	struct ll_dentry_data *lld = kzalloc(sizeof(*lld), GFP_KERNEL);
+	if (unlikely(!lld))
+		return -ENOMEM;
+	lld->lld_invalid = 1;
+	de->d_fsdata = lld;
 	return 0;
 }
 
@@ -300,6 +280,7 @@ static int ll_revalidate_nd(struct dentry *dentry, unsigned int flags)
 }
 
 const struct dentry_operations ll_d_ops = {
+	.d_init = ll_d_init,
 	.d_revalidate = ll_revalidate_nd,
 	.d_release = ll_release,
 	.d_delete  = ll_ddelete,

drivers/staging/lustre/lustre/llite/llite_internal.h

@@ -801,7 +801,6 @@ int ll_hsm_release(struct inode *inode);
 
 /* llite/dcache.c */
 
-int ll_d_init(struct dentry *de);
 extern const struct dentry_operations ll_d_ops;
 void ll_intent_drop_lock(struct lookup_intent *);
 void ll_intent_release(struct lookup_intent *);
@@ -1189,7 +1188,7 @@ dentry_may_statahead(struct inode *dir, struct dentry *dentry)
 	 * 'lld_sa_generation == lli->lli_sa_generation'.
 	 */
 	ldd = ll_d2d(dentry);
-	if (ldd && ldd->lld_sa_generation == lli->lli_sa_generation)
+	if (ldd->lld_sa_generation == lli->lli_sa_generation)
 		return false;
 
 	return true;
@@ -1317,17 +1316,7 @@ static inline void ll_set_lock_data(struct obd_export *exp, struct inode *inode,
 
 static inline int d_lustre_invalid(const struct dentry *dentry)
 {
-	struct ll_dentry_data *lld = ll_d2d(dentry);
-
-	return !lld || lld->lld_invalid;
-}
-
-static inline void __d_lustre_invalidate(struct dentry *dentry)
-{
-	struct ll_dentry_data *lld = ll_d2d(dentry);
-
-	if (lld)
-		lld->lld_invalid = 1;
+	return ll_d2d(dentry)->lld_invalid;
 }
 
 /*
@@ -1343,7 +1332,7 @@ static inline void d_lustre_invalidate(struct dentry *dentry, int nested)
 
 	spin_lock_nested(&dentry->d_lock,
 			 nested ? DENTRY_D_LOCK_NESTED : DENTRY_D_LOCK_NORMAL);
-	__d_lustre_invalidate(dentry);
+	ll_d2d(dentry)->lld_invalid = 1;
 	/*
 	 * We should be careful about dentries created by d_obtain_alias().
 	 * These dentries are not put in the dentry tree, instead they are

drivers/staging/lustre/lustre/llite/llite_nfs.c

@@ -169,22 +169,12 @@ ll_iget_for_nfs(struct super_block *sb, struct lu_fid *fid, struct lu_fid *paren
 	/* N.B. d_obtain_alias() drops inode ref on error */
 	result = d_obtain_alias(inode);
 	if (!IS_ERR(result)) {
-		int rc;
-
-		rc = ll_d_init(result);
-		if (rc < 0) {
-			dput(result);
-			result = ERR_PTR(rc);
-		} else {
-			struct ll_dentry_data *ldd = ll_d2d(result);
-
-			/*
-			 * Need to signal to the ll_intent_file_open that
-			 * we came from NFS and so opencache needs to be
-			 * enabled for this one
-			 */
-			ldd->lld_nfs_dentry = 1;
-		}
+		/*
+		 * Need to signal to the ll_intent_file_open that
+		 * we came from NFS and so opencache needs to be
+		 * enabled for this one
+		 */
+		ll_d2d(result)->lld_nfs_dentry = 1;
 	}
 
 	return result;

drivers/staging/lustre/lustre/llite/namei.c

@@ -395,17 +395,9 @@ static struct dentry *ll_find_alias(struct inode *inode, struct dentry *dentry)
  */
 struct dentry *ll_splice_alias(struct inode *inode, struct dentry *de)
 {
-	struct dentry *new;
-	int rc;
-
 	if (inode) {
-		new = ll_find_alias(inode, de);
+		struct dentry *new = ll_find_alias(inode, de);
 		if (new) {
-			rc = ll_d_init(new);
-			if (rc < 0) {
-				dput(new);
-				return ERR_PTR(rc);
-			}
 			d_move(new, de);
 			iput(inode);
 			CDEBUG(D_DENTRY,
@@ -414,9 +406,6 @@ struct dentry *ll_splice_alias(struct inode *inode, struct dentry *de)
 			return new;
 		}
 	}
-	rc = ll_d_init(de);
-	if (rc < 0)
-		return ERR_PTR(rc);
 	d_add(de, inode);
 	CDEBUG(D_DENTRY, "Add dentry %p inode %p refc %d flags %#x\n",
 	       de, d_inode(de), d_count(de), de->d_flags);

drivers/staging/lustre/lustre/llite/statahead.c

@@ -1513,9 +1513,7 @@ out_unplug:
 	 */
 	ldd = ll_d2d(*dentryp);
 	lli = ll_i2info(dir);
-	/* ldd can be NULL if llite lookup failed. */
-	if (ldd)
-		ldd->lld_sa_generation = lli->lli_sa_generation;
+	ldd->lld_sa_generation = lli->lli_sa_generation;
 	sa_put(sai, entry);
 	return rc;
 }

drivers/usb/gadget/function/f_fs.c

@@ -949,7 +949,7 @@ static ssize_t ffs_epfile_io(struct file *file, struct ffs_io_data *io_data)
 			goto error_mutex;
 		}
 		if (!io_data->read &&
-		    copy_from_iter(data, data_len, &io_data->data) != data_len) {
+		    !copy_from_iter_full(data, data_len, &io_data->data)) {
 			ret = -EFAULT;
 			goto error_mutex;
 		}

drivers/usb/gadget/legacy/inode.c

@@ -667,7 +667,7 @@ ep_write_iter(struct kiocb *iocb, struct iov_iter *from)
 		return -ENOMEM;
 	}
 
-	if (unlikely(copy_from_iter(buf, len, from) != len)) {
+	if (unlikely(!copy_from_iter_full(buf, len, from))) {
 		value = -EFAULT;
 		goto out;
 	}

drivers/vhost/scsi.c

@@ -922,8 +922,7 @@ vhost_scsi_handle_vq(struct vhost_scsi *vs, struct vhost_virtqueue *vq)
 		 */
 		iov_iter_init(&out_iter, WRITE, vq->iov, out, out_size);
 
-		ret = copy_from_iter(req, req_size, &out_iter);
-		if (unlikely(ret != req_size)) {
+		if (unlikely(!copy_from_iter_full(req, req_size, &out_iter))) {
 			vq_err(vq, "Faulted on copy_from_iter\n");
 			vhost_scsi_send_bad_target(vs, vq, head, out);
 			continue;

drivers/vhost/vhost.c

@@ -1862,8 +1862,7 @@ static int get_indirect(struct vhost_virtqueue *vq,
 			       i, count);
 			return -EINVAL;
 		}
-		if (unlikely(copy_from_iter(&desc, sizeof(desc), &from) !=
-			     sizeof(desc))) {
+		if (unlikely(!copy_from_iter_full(&desc, sizeof(desc), &from))) {
 			vq_err(vq, "Failed indirect descriptor: idx %d, %zx\n",
 			       i, (size_t)vhost64_to_cpu(vq, indirect->addr) + i * sizeof desc);
 			return -EINVAL;

fs/ceph/dir.c

@@ -32,40 +32,19 @@ const struct dentry_operations ceph_dentry_ops;
 /*
  * Initialize ceph dentry state.
  */
-int ceph_init_dentry(struct dentry *dentry)
+static int ceph_d_init(struct dentry *dentry)
 {
 	struct ceph_dentry_info *di;
 
-	if (dentry->d_fsdata)
-		return 0;
-
 	di = kmem_cache_zalloc(ceph_dentry_cachep, GFP_KERNEL);
 	if (!di)
 		return -ENOMEM;          /* oh well */
 
-	spin_lock(&dentry->d_lock);
-	if (dentry->d_fsdata) {
-		/* lost a race */
-		kmem_cache_free(ceph_dentry_cachep, di);
-		goto out_unlock;
-	}
-
-	if (ceph_snap(d_inode(dentry->d_parent)) == CEPH_NOSNAP)
-		d_set_d_op(dentry, &ceph_dentry_ops);
-	else if (ceph_snap(d_inode(dentry->d_parent)) == CEPH_SNAPDIR)
-		d_set_d_op(dentry, &ceph_snapdir_dentry_ops);
-	else
-		d_set_d_op(dentry, &ceph_snap_dentry_ops);
-
 	di->dentry = dentry;
 	di->lease_session = NULL;
 	di->time = jiffies;
-	/* avoid reordering d_fsdata setup so that the check above is safe */
-	smp_mb();
 	dentry->d_fsdata = di;
 	ceph_dentry_lru_add(dentry);
-out_unlock:
-	spin_unlock(&dentry->d_lock);
 	return 0;
 }
 
@@ -737,10 +716,6 @@ static struct dentry *ceph_lookup(struct inode *dir, struct dentry *dentry,
 	if (dentry->d_name.len > NAME_MAX)
 		return ERR_PTR(-ENAMETOOLONG);
 
-	err = ceph_init_dentry(dentry);
-	if (err < 0)
-		return ERR_PTR(err);
-
 	/* can we conclude ENOENT locally? */
 	if (d_really_is_negative(dentry)) {
 		struct ceph_inode_info *ci = ceph_inode(dir);
@@ -1319,16 +1294,6 @@ static void ceph_d_release(struct dentry *dentry)
 	kmem_cache_free(ceph_dentry_cachep, di);
 }
 
-static int ceph_snapdir_d_revalidate(struct dentry *dentry,
-					  unsigned int flags)
-{
-	/*
-	 * Eventually, we'll want to revalidate snapped metadata
-	 * too... probably...
-	 */
-	return 1;
-}
-
 /*
  * When the VFS prunes a dentry from the cache, we need to clear the
  * complete flag on the parent directory.
@@ -1347,6 +1312,9 @@ static void ceph_d_prune(struct dentry *dentry)
 	if (d_unhashed(dentry))
 		return;
 
+	if (ceph_snap(d_inode(dentry->d_parent)) == CEPH_SNAPDIR)
+		return;
+
 	/*
 	 * we hold d_lock, so d_parent is stable, and d_fsdata is never
 	 * cleared until d_release
@@ -1517,14 +1485,5 @@ const struct dentry_operations ceph_dentry_ops = {
 	.d_revalidate = ceph_d_revalidate,
 	.d_release = ceph_d_release,
 	.d_prune = ceph_d_prune,
-};
-
-const struct dentry_operations ceph_snapdir_dentry_ops = {
-	.d_revalidate = ceph_snapdir_d_revalidate,
-	.d_release = ceph_d_release,
-};
-
-const struct dentry_operations ceph_snap_dentry_ops = {
-	.d_release = ceph_d_release,
-	.d_prune = ceph_d_prune,
+	.d_init = ceph_d_init,
 };

fs/ceph/export.c

@@ -62,7 +62,6 @@ static struct dentry *__fh_to_dentry(struct super_block *sb, u64 ino)
 {
 	struct ceph_mds_client *mdsc = ceph_sb_to_client(sb)->mdsc;
 	struct inode *inode;
-	struct dentry *dentry;
 	struct ceph_vino vino;
 	int err;
 
@@ -94,16 +93,7 @@ static struct dentry *__fh_to_dentry(struct super_block *sb, u64 ino)
 			return ERR_PTR(-ESTALE);
 	}
 
-	dentry = d_obtain_alias(inode);
-	if (IS_ERR(dentry))
-		return dentry;
-	err = ceph_init_dentry(dentry);
-	if (err < 0) {
-		dput(dentry);
-		return ERR_PTR(err);
-	}
-	dout("__fh_to_dentry %llx %p dentry %p\n", ino, inode, dentry);
-	return dentry;
+	return d_obtain_alias(inode);
 }
 
 /*
@@ -131,7 +121,6 @@ static struct dentry *__get_parent(struct super_block *sb,
 	struct ceph_mds_client *mdsc = ceph_sb_to_client(sb)->mdsc;
 	struct ceph_mds_request *req;
 	struct inode *inode;
-	struct dentry *dentry;
 	int mask;
 	int err;
 
@@ -164,18 +153,7 @@ static struct dentry *__get_parent(struct super_block *sb,
 	if (!inode)
 		return ERR_PTR(-ENOENT);
 
-	dentry = d_obtain_alias(inode);
-	if (IS_ERR(dentry))
-		return dentry;
-	err = ceph_init_dentry(dentry);
-	if (err < 0) {
-		dput(dentry);
-		return ERR_PTR(err);
-	}
-	dout("__get_parent ino %llx parent %p ino %llx.%llx\n",
-	     child ? ceph_ino(d_inode(child)) : ino,
-	     dentry, ceph_vinop(inode));
-	return dentry;
+	return d_obtain_alias(inode);
 }
 
 static struct dentry *ceph_get_parent(struct dentry *child)

fs/ceph/file.c

@@ -351,10 +351,6 @@ int ceph_atomic_open(struct inode *dir, struct dentry *dentry,
 	if (dentry->d_name.len > NAME_MAX)
 		return -ENAMETOOLONG;
 
-	err = ceph_init_dentry(dentry);
-	if (err < 0)
-		return err;
-
 	if (flags & O_CREAT) {
 		err = ceph_pre_init_acls(dir, &mode, &acls);
 		if (err < 0)

fs/ceph/inode.c

@@ -1023,16 +1023,17 @@ static void update_dentry_lease(struct dentry *dentry,
 	long unsigned half_ttl = from_time + (duration * HZ / 2) / 1000;
 	struct inode *dir;
 
-	/* only track leases on regular dentries */
-	if (dentry->d_op != &ceph_dentry_ops)
-		return;
-
 	spin_lock(&dentry->d_lock);
 	dout("update_dentry_lease %p duration %lu ms ttl %lu\n",
 	     dentry, duration, ttl);
 
 	/* make lease_rdcache_gen match directory */
 	dir = d_inode(dentry->d_parent);
+
+	/* only track leases on regular dentries */
+	if (ceph_snap(dir) != CEPH_NOSNAP)
+		goto out_unlock;
+
 	di->lease_shared_gen = ceph_inode(dir)->i_shared_gen;
 
 	if (duration == 0)
@@ -1202,12 +1203,7 @@ retry_lookup:
 					err = -ENOMEM;
 					goto done;
 				}
-				err = ceph_init_dentry(dn);
-				if (err < 0) {
-					dput(dn);
-					dput(parent);
-					goto done;
-				}
+				err = 0;
 			} else if (d_really_is_positive(dn) &&
 				   (ceph_ino(d_inode(dn)) != vino.ino ||
 				    ceph_snap(d_inode(dn)) != vino.snap)) {
@@ -1561,12 +1557,6 @@ retry_lookup:
 				err = -ENOMEM;
 				goto out;
 			}
-			ret = ceph_init_dentry(dn);
-			if (ret < 0) {
-				dput(dn);
-				err = ret;
-				goto out;
-			}
 		} else if (d_really_is_positive(dn) &&
 			   (ceph_ino(d_inode(dn)) != vino.ino ||
 			    ceph_snap(d_inode(dn)) != vino.snap)) {

fs/ceph/super.c

@@ -795,7 +795,6 @@ static struct dentry *open_root_dentry(struct ceph_fs_client *fsc,
 			root = ERR_PTR(-ENOMEM);
 			goto out;
 		}
-		ceph_init_dentry(root);
 		dout("open_root_inode success, root dentry is %p\n", root);
 	} else {
 		root = ERR_PTR(err);
@@ -879,6 +878,7 @@ static int ceph_set_super(struct super_block *s, void *data)
 	fsc->sb = s;
 
 	s->s_op = &ceph_super_ops;
+	s->s_d_op = &ceph_dentry_ops;
 	s->s_export_op = &ceph_export_ops;
 
 	s->s_time_gran = 1000;  /* 1000 ns == 1 us */

fs/ceph/super.h

@@ -934,8 +934,7 @@ extern const struct file_operations ceph_dir_fops;
 extern const struct file_operations ceph_snapdir_fops;
 extern const struct inode_operations ceph_dir_iops;
 extern const struct inode_operations ceph_snapdir_iops;
-extern const struct dentry_operations ceph_dentry_ops, ceph_snap_dentry_ops,
-	ceph_snapdir_dentry_ops;
+extern const struct dentry_operations ceph_dentry_ops;
 
 extern loff_t ceph_make_fpos(unsigned high, unsigned off, bool hash_order);
 extern int ceph_handle_notrace_create(struct inode *dir, struct dentry *dentry);
@@ -951,13 +950,6 @@ extern void ceph_invalidate_dentry_lease(struct dentry *dentry);
 extern unsigned ceph_dentry_hash(struct inode *dir, struct dentry *dn);
 extern void ceph_readdir_cache_release(struct ceph_readdir_cache_control *ctl);
 
-/*
- * our d_ops vary depending on whether the inode is live,
- * snapshotted (read-only), or a virtual ".snap" directory.
- */
-int ceph_init_dentry(struct dentry *dentry);
-
-
 /* ioctl.c */
 extern long ceph_ioctl(struct file *file, unsigned int cmd, unsigned long arg);
 

fs/namei.c

@@ -1725,30 +1725,35 @@ static int pick_link(struct nameidata *nd, struct path *link,
 	return 1;
 }
 
+enum {WALK_FOLLOW = 1, WALK_MORE = 2};
+
 /*
  * Do we need to follow links? We _really_ want to be able
  * to do this check without having to look at inode->i_op,
  * so we keep a cache of "no, this doesn't need follow_link"
  * for the common case.
  */
-static inline int should_follow_link(struct nameidata *nd, struct path *link,
-				     int follow,
-				     struct inode *inode, unsigned seq)
+static inline int step_into(struct nameidata *nd, struct path *path,
+			    int flags, struct inode *inode, unsigned seq)
 {
-	if (likely(!d_is_symlink(link->dentry)))
-		return 0;
-	if (!follow)
+	if (!(flags & WALK_MORE) && nd->depth)
+		put_link(nd);
+	if (likely(!d_is_symlink(path->dentry)) ||
+	   !(flags & WALK_FOLLOW || nd->flags & LOOKUP_FOLLOW)) {
+		/* not a symlink or should not follow */
+		path_to_nameidata(path, nd);
+		nd->inode = inode;
+		nd->seq = seq;
 		return 0;
+	}
 	/* make sure that d_is_symlink above matches inode */
 	if (nd->flags & LOOKUP_RCU) {
-		if (read_seqcount_retry(&link->dentry->d_seq, seq))
+		if (read_seqcount_retry(&path->dentry->d_seq, seq))
 			return -ECHILD;
 	}
-	return pick_link(nd, link, inode, seq);
+	return pick_link(nd, path, inode, seq);
 }
 
-enum {WALK_GET = 1, WALK_PUT = 2};
-
 static int walk_component(struct nameidata *nd, int flags)
 {
 	struct path path;
@@ -1762,7 +1767,7 @@ static int walk_component(struct nameidata *nd, int flags)
 	 */
 	if (unlikely(nd->last_type != LAST_NORM)) {
 		err = handle_dots(nd, nd->last_type);
-		if (flags & WALK_PUT)
+		if (!(flags & WALK_MORE) && nd->depth)
 			put_link(nd);
 		return err;
 	}
@@ -1789,15 +1794,7 @@ static int walk_component(struct nameidata *nd, int flags)
 		inode = d_backing_inode(path.dentry);
 	}
 
-	if (flags & WALK_PUT)
-		put_link(nd);
-	err = should_follow_link(nd, &path, flags & WALK_GET, inode, seq);
-	if (unlikely(err))
-		return err;
-	path_to_nameidata(&path, nd);
-	nd->inode = inode;
-	nd->seq = seq;
-	return 0;
+	return step_into(nd, &path, flags, inode, seq);
 }
 
 /*
@@ -2104,9 +2101,10 @@ OK:
 			if (!name)
 				return 0;
 			/* last component of nested symlink */
-			err = walk_component(nd, WALK_GET | WALK_PUT);
+			err = walk_component(nd, WALK_FOLLOW);
 		} else {
-			err = walk_component(nd, WALK_GET);
+			/* not the last component */
+			err = walk_component(nd, WALK_FOLLOW | WALK_MORE);
 		}
 		if (err < 0)
 			return err;
@@ -2248,12 +2246,7 @@ static inline int lookup_last(struct nameidata *nd)
 		nd->flags |= LOOKUP_FOLLOW | LOOKUP_DIRECTORY;
 
 	nd->flags &= ~LOOKUP_PARENT;
-	return walk_component(nd,
-			nd->flags & LOOKUP_FOLLOW
-				? nd->depth
-					? WALK_PUT | WALK_GET
-					: WALK_GET
-				: 0);
+	return walk_component(nd, 0);
 }
 
 /* Returns 0 and nd will be valid on success; Retuns error, otherwise. */
@@ -2558,28 +2551,9 @@ int user_path_at_empty(int dfd, const char __user *name, unsigned flags,
 }
 EXPORT_SYMBOL(user_path_at_empty);
 
-/*
- * NB: most callers don't do anything directly with the reference to the
- *     to struct filename, but the nd->last pointer points into the name string
- *     allocated by getname. So we must hold the reference to it until all
- *     path-walking is complete.
- */
-static inline struct filename *
-user_path_parent(int dfd, const char __user *path,
-		 struct path *parent,
-		 struct qstr *last,
-		 int *type,
-		 unsigned int flags)
-{
-	/* only LOOKUP_REVAL is allowed in extra flags */
-	return filename_parentat(dfd, getname(path), flags & LOOKUP_REVAL,
-				 parent, last, type);
-}
-
 /**
  * mountpoint_last - look up last component for umount
  * @nd:   pathwalk nameidata - currently pointing at parent directory of "last"
- * @path: pointer to container for result
  *
  * This is a special lookup_last function just for umount. In this case, we
  * need to resolve the path without doing any revalidation.
@@ -2592,23 +2566,20 @@ user_path_parent(int dfd, const char __user *path,
  *
  * Returns:
  * -error: if there was an error during lookup. This includes -ENOENT if the
- *         lookup found a negative dentry. The nd->path reference will also be
- *         put in this case.
+ *         lookup found a negative dentry.
  *
- * 0:      if we successfully resolved nd->path and found it to not to be a
- *         symlink that needs to be followed. "path" will also be populated.
- *         The nd->path reference will also be put.
+ * 0:      if we successfully resolved nd->last and found it to not to be a
+ *         symlink that needs to be followed.
  *
  * 1:      if we successfully resolved nd->last and found it to be a symlink
- *         that needs to be followed. "path" will be populated with the path
- *         to the link, and nd->path will *not* be put.
+ *         that needs to be followed.
  */
 static int
-mountpoint_last(struct nameidata *nd, struct path *path)
+mountpoint_last(struct nameidata *nd)
 {
 	int error = 0;
-	struct dentry *dentry;
 	struct dentry *dir = nd->path.dentry;
+	struct path path;
 
 	/* If we're in rcuwalk, drop out of it to handle last component */
 	if (nd->flags & LOOKUP_RCU) {
@@ -2622,37 +2593,28 @@ mountpoint_last(struct nameidata *nd, struct path *path)
 		error = handle_dots(nd, nd->last_type);
 		if (error)
 			return error;
-		dentry = dget(nd->path.dentry);
+		path.dentry = dget(nd->path.dentry);
 	} else {
-		dentry = d_lookup(dir, &nd->last);
-		if (!dentry) {
+		path.dentry = d_lookup(dir, &nd->last);
+		if (!path.dentry) {
 			/*
 			 * No cached dentry. Mounted dentries are pinned in the
 			 * cache, so that means that this dentry is probably
 			 * a symlink or the path doesn't actually point
 			 * to a mounted dentry.
 			 */
-			dentry = lookup_slow(&nd->last, dir,
+			path.dentry = lookup_slow(&nd->last, dir,
 					     nd->flags | LOOKUP_NO_REVAL);
-			if (IS_ERR(dentry))
-				return PTR_ERR(dentry);
+			if (IS_ERR(path.dentry))
+				return PTR_ERR(path.dentry);
 		}
 	}
-	if (d_is_negative(dentry)) {
-		dput(dentry);
+	if (d_is_negative(path.dentry)) {
+		dput(path.dentry);
 		return -ENOENT;
 	}
-	if (nd->depth)
-		put_link(nd);
-	path->dentry = dentry;
-	path->mnt = nd->path.mnt;
-	error = should_follow_link(nd, path, nd->flags & LOOKUP_FOLLOW,
-				   d_backing_inode(dentry), 0);
-	if (unlikely(error))
-		return error;
-	mntget(path->mnt);
-	follow_mount(path);
-	return 0;
+	path.mnt = nd->path.mnt;
+	return step_into(nd, &path, 0, d_backing_inode(path.dentry), 0);
 }
 
 /**
@@ -2672,13 +2634,19 @@ path_mountpoint(struct nameidata *nd, unsigned flags, struct path *path)
 	if (IS_ERR(s))
 		return PTR_ERR(s);
 	while (!(err = link_path_walk(s, nd)) &&
-		(err = mountpoint_last(nd, path)) > 0) {
+		(err = mountpoint_last(nd)) > 0) {
 		s = trailing_symlink(nd);
 		if (IS_ERR(s)) {
 			err = PTR_ERR(s);
 			break;
 		}
 	}
+	if (!err) {
+		*path = nd->path;
+		nd->path.mnt = NULL;
+		nd->path.dentry = NULL;
+		follow_mount(path);
+	}
 	terminate_walk(nd);
 	return err;
 }
@@ -3335,18 +3303,11 @@ static int do_last(struct nameidata *nd,
 	seq = 0;	/* out of RCU mode, so the value doesn't matter */
 	inode = d_backing_inode(path.dentry);
 finish_lookup:
-	if (nd->depth)
-		put_link(nd);
-	error = should_follow_link(nd, &path, nd->flags & LOOKUP_FOLLOW,
-				   inode, seq);
+	error = step_into(nd, &path, 0, inode, seq);
 	if (unlikely(error))
 		return error;
-
-	path_to_nameidata(&path, nd);
-	nd->inode = inode;
-	nd->seq = seq;
-	/* Why this, you ask?  _Now_ we might have grown LOOKUP_JUMPED... */
 finish_open:
+	/* Why this, you ask?  _Now_ we might have grown LOOKUP_JUMPED... */
 	error = complete_walk(nd);
 	if (error)
 		return error;
@@ -3861,8 +3822,8 @@ static long do_rmdir(int dfd, const char __user *pathname)
 	int type;
 	unsigned int lookup_flags = 0;
 retry:
-	name = user_path_parent(dfd, pathname,
-				&path, &last, &type, lookup_flags);
+	name = filename_parentat(dfd, getname(pathname), lookup_flags,
+				&path, &last, &type);
 	if (IS_ERR(name))
 		return PTR_ERR(name);
 
@@ -3991,8 +3952,8 @@ static long do_unlinkat(int dfd, const char __user *pathname)
 	struct inode *delegated_inode = NULL;
 	unsigned int lookup_flags = 0;
 retry:
-	name = user_path_parent(dfd, pathname,
-				&path, &last, &type, lookup_flags);
+	name = filename_parentat(dfd, getname(pathname), lookup_flags,
+				&path, &last, &type);
 	if (IS_ERR(name))
 		return PTR_ERR(name);
 
@@ -4491,15 +4452,15 @@ SYSCALL_DEFINE5(renameat2, int, olddfd, const char __user *, oldname,
 		target_flags = 0;
 
 retry:
-	from = user_path_parent(olddfd, oldname,
-				&old_path, &old_last, &old_type, lookup_flags);
+	from = filename_parentat(olddfd, getname(oldname), lookup_flags,
+				&old_path, &old_last, &old_type);
 	if (IS_ERR(from)) {
 		error = PTR_ERR(from);
 		goto exit;
 	}
 
-	to = user_path_parent(newdfd, newname,
-				&new_path, &new_last, &new_type, lookup_flags);
+	to = filename_parentat(newdfd, getname(newname), lookup_flags,
+				&new_path, &new_last, &new_type);
 	if (IS_ERR(to)) {
 		error = PTR_ERR(to);
 		goto exit1;

fs/ncpfs/file.c

@@ -203,7 +203,7 @@ ncp_file_write_iter(struct kiocb *iocb, struct iov_iter *from)
 				      bufsize - (pos % bufsize),
 				      iov_iter_count(from));
 
-		if (copy_from_iter(bouncebuffer, to_write, from) != to_write) {
+		if (!copy_from_iter_full(bouncebuffer, to_write, from)) {
 			errno = -EFAULT;
 			break;
 		}