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

drivers/bluetooth/hci_vhci.c

···
 	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

···
 	int depth;
 	bool zerocopy = false;
 	size_t linear;
-	ssize_t n;
 
 	if (q->flags & IFF_VNET_HDR) {
 		vnet_hdr_len = q->vnet_hdr_sz;
···
 		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

···
 	bool zerocopy = false;
 	int err;
 	u32 rxhash;
-	ssize_t n;
 
 	if (!(tun->dev->flags & IFF_UP))
 		return -EIO;
···
 			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;
 	}
 
···
 			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

···
 
 	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);
···
 	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;
 }
 
···
 }
 
 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

···
 
 /* 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 *);
···
 	 * '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;
···
 
 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;
 }
 
 /*
···
 
 	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

···
 	/* 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

···
  */
 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,
···
 			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

···
 	 */
 	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

···
 			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

···
 		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

···
 		 */
 		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

···
 			       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

···
 /*
  * 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;
 }
 
···
 	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);
···
 	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.
···
 
 	/* if we are not hashed, we don't affect dir's completeness */
 	if (d_unhashed(dentry))
+		return;
+
+	if (ceph_snap(d_inode(dentry->d_parent)) == CEPH_SNAPDIR)
 		return;
 
 	/*
···
 	.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

···
 {
 	struct ceph_mds_client *mdsc = ceph_sb_to_client(sb)->mdsc;
 	struct inode *inode;
-	struct dentry *dentry;
 	struct ceph_vino vino;
 	int err;
 
···
 			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);
 }
 
 /*
···
 	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;
 
···
 	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

···
 	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

···
 	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)
···
 					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)) {
···
 			if (dn == NULL) {
 				dout("d_alloc badness\n");
 				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) &&

fs/ceph/super.c

···
 			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);
···
 	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

···
 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);
···
 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

···
 	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)))
+	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;
-	if (!follow)
-		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)
 {
···
 	 */
 	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;
 	}
···
 		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);
 }
 
 /*
···
 			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;
···
 		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. */
···
 }
 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.
···
  *
  * 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) {
···
 		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);
 }
 
 /**
···
 	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;
···
 	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;
···
 	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);
 
···
 	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);
 
···
 		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

···
 				      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;
 		}

fs/orangefs/devorangefs-req.c

···
 		__u64 tag;
 	} head;
 	int total = ret = iov_iter_count(iter);
-	int n;
 	int downcall_size = sizeof(struct orangefs_downcall_s);
 	int head_size = sizeof(head);
 
···
 		return -EFAULT;
 	}
      
-	n = copy_from_iter(&head, head_size, iter);
-	if (n < head_size) {
+	if (!copy_from_iter_full(&head, head_size, iter)) {
 		gossip_err("%s: failed to copy head.\n", __func__);
 		return -EFAULT;
 	}
···
 		return ret;
 	}
 
-	n = copy_from_iter(&op->downcall, downcall_size, iter);
-	if (n != downcall_size) {
+	if (!copy_from_iter_full(&op->downcall, downcall_size, iter)) {
 		gossip_err("%s: failed to copy downcall.\n", __func__);
 		goto Efault;
 	}
···
 		goto Enomem;
 	}
 	memset(op->downcall.trailer_buf, 0, op->downcall.trailer_size);
-	n = copy_from_iter(op->downcall.trailer_buf,
-			   op->downcall.trailer_size,
-			   iter);
-	if (n != op->downcall.trailer_size) {
+	if (!copy_from_iter_full(op->downcall.trailer_buf,
+			         op->downcall.trailer_size, iter)) {
 		gossip_err("%s: failed to copy trailer.\n", __func__);
 		vfree(op->downcall.trailer_buf);
 		goto Efault;

include/linux/skbuff.h

···
 
 	if (skb->ip_summed == CHECKSUM_NONE) {
 		__wsum csum = 0;
-		if (csum_and_copy_from_iter(skb_put(skb, copy), copy,
-					    &csum, from) == copy) {
+		if (csum_and_copy_from_iter_full(skb_put(skb, copy), copy,
+					         &csum, from)) {
 			skb->csum = csum_block_add(skb->csum, csum, off);
 			return 0;
 		}
-	} else if (copy_from_iter(skb_put(skb, copy), copy, from) == copy)
+	} else if (copy_from_iter_full(skb_put(skb, copy), copy, from))
 		return 0;
 
 	__skb_trim(skb, off);

include/linux/uio.h

···
 			 struct iov_iter *i);
 size_t copy_to_iter(const void *addr, size_t bytes, struct iov_iter *i);
 size_t copy_from_iter(void *addr, size_t bytes, struct iov_iter *i);
+bool copy_from_iter_full(void *addr, size_t bytes, struct iov_iter *i);
 size_t copy_from_iter_nocache(void *addr, size_t bytes, struct iov_iter *i);
+bool copy_from_iter_full_nocache(void *addr, size_t bytes, struct iov_iter *i);
 size_t iov_iter_zero(size_t bytes, struct iov_iter *);
 unsigned long iov_iter_alignment(const struct iov_iter *i);
 unsigned long iov_iter_gap_alignment(const struct iov_iter *i);
···
 }
 size_t csum_and_copy_to_iter(const void *addr, size_t bytes, __wsum *csum, struct iov_iter *i);
 size_t csum_and_copy_from_iter(void *addr, size_t bytes, __wsum *csum, struct iov_iter *i);
+bool csum_and_copy_from_iter_full(void *addr, size_t bytes, __wsum *csum, struct iov_iter *i);
 
 int import_iovec(int type, const struct iovec __user * uvector,
 		 unsigned nr_segs, unsigned fast_segs,

include/net/sock.h

···
 {
 	if (skb->ip_summed == CHECKSUM_NONE) {
 		__wsum csum = 0;
-		if (csum_and_copy_from_iter(to, copy, &csum, from) != copy)
+		if (!csum_and_copy_from_iter_full(to, copy, &csum, from))
 			return -EFAULT;
 		skb->csum = csum_block_add(skb->csum, csum, offset);
 	} else if (sk->sk_route_caps & NETIF_F_NOCACHE_COPY) {
-		if (copy_from_iter_nocache(to, copy, from) != copy)
+		if (!copy_from_iter_full_nocache(to, copy, from))
 			return -EFAULT;
-	} else if (copy_from_iter(to, copy, from) != copy)
+	} else if (!copy_from_iter_full(to, copy, from))
 		return -EFAULT;
 
 	return 0;

include/net/udplite.h

···
 				      int len, int odd, struct sk_buff *skb)
 {
 	struct msghdr *msg = from;
-	return copy_from_iter(to, len, &msg->msg_iter) != len ? -EFAULT : 0;
+	return copy_from_iter_full(to, len, &msg->msg_iter) ? 0 : -EFAULT;
 }
 
 /* Designate sk as UDP-Lite socket */

kernel/printk/printk.c

···
 		return -ENOMEM;
 
 	buf[len] = '\0';
-	if (copy_from_iter(buf, len, from) != len) {
+	if (!copy_from_iter_full(buf, len, from)) {
 		kfree(buf);
 		return -EFAULT;
 	}

lib/iov_iter.c

···
 }
 EXPORT_SYMBOL(copy_from_iter);
 
+bool copy_from_iter_full(void *addr, size_t bytes, struct iov_iter *i)
+{
+	char *to = addr;
+	if (unlikely(i->type & ITER_PIPE)) {
+		WARN_ON(1);
+		return false;
+	}
+	if (unlikely(i->count < bytes))				\
+		return false;
+
+	iterate_all_kinds(i, bytes, v, ({
+		if (__copy_from_user((to += v.iov_len) - v.iov_len,
+				      v.iov_base, v.iov_len))
+			return false;
+		0;}),
+		memcpy_from_page((to += v.bv_len) - v.bv_len, v.bv_page,
+				 v.bv_offset, v.bv_len),
+		memcpy((to += v.iov_len) - v.iov_len, v.iov_base, v.iov_len)
+	)
+
+	iov_iter_advance(i, bytes);
+	return true;
+}
+EXPORT_SYMBOL(copy_from_iter_full);
+
 size_t copy_from_iter_nocache(void *addr, size_t bytes, struct iov_iter *i)
 {
 	char *to = addr;
···
 	return bytes;
 }
 EXPORT_SYMBOL(copy_from_iter_nocache);
+
+bool copy_from_iter_full_nocache(void *addr, size_t bytes, struct iov_iter *i)
+{
+	char *to = addr;
+	if (unlikely(i->type & ITER_PIPE)) {
+		WARN_ON(1);
+		return false;
+	}
+	if (unlikely(i->count < bytes))				\
+		return false;
+	iterate_all_kinds(i, bytes, v, ({
+		if (__copy_from_user_nocache((to += v.iov_len) - v.iov_len,
+					     v.iov_base, v.iov_len))
+			return false;
+		0;}),
+		memcpy_from_page((to += v.bv_len) - v.bv_len, v.bv_page,
+				 v.bv_offset, v.bv_len),
+		memcpy((to += v.iov_len) - v.iov_len, v.iov_base, v.iov_len)
+	)
+
+	iov_iter_advance(i, bytes);
+	return true;
+}
+EXPORT_SYMBOL(copy_from_iter_full_nocache);
 
 size_t copy_page_to_iter(struct page *page, size_t offset, size_t bytes,
 			 struct iov_iter *i)
···
 	}
 	iterate_and_advance(i, bytes, v, ({
 		int err = 0;
-		next = csum_and_copy_from_user(v.iov_base, 
+		next = csum_and_copy_from_user(v.iov_base,
 					       (to += v.iov_len) - v.iov_len,
 					       v.iov_len, 0, &err);
 		if (!err) {
···
 }
 EXPORT_SYMBOL(csum_and_copy_from_iter);
 
+bool csum_and_copy_from_iter_full(void *addr, size_t bytes, __wsum *csum,
+			       struct iov_iter *i)
+{
+	char *to = addr;
+	__wsum sum, next;
+	size_t off = 0;
+	sum = *csum;
+	if (unlikely(i->type & ITER_PIPE)) {
+		WARN_ON(1);
+		return false;
+	}
+	if (unlikely(i->count < bytes))
+		return false;
+	iterate_all_kinds(i, bytes, v, ({
+		int err = 0;
+		next = csum_and_copy_from_user(v.iov_base,
+					       (to += v.iov_len) - v.iov_len,
+					       v.iov_len, 0, &err);
+		if (err)
+			return false;
+		sum = csum_block_add(sum, next, off);
+		off += v.iov_len;
+		0;
+	}), ({
+		char *p = kmap_atomic(v.bv_page);
+		next = csum_partial_copy_nocheck(p + v.bv_offset,
+						 (to += v.bv_len) - v.bv_len,
+						 v.bv_len, 0);
+		kunmap_atomic(p);
+		sum = csum_block_add(sum, next, off);
+		off += v.bv_len;
+	}),({
+		next = csum_partial_copy_nocheck(v.iov_base,
+						 (to += v.iov_len) - v.iov_len,
+						 v.iov_len, 0);
+		sum = csum_block_add(sum, next, off);
+		off += v.iov_len;
+	})
+	)
+	*csum = sum;
+	iov_iter_advance(i, bytes);
+	return true;
+}
+EXPORT_SYMBOL(csum_and_copy_from_iter_full);
+
 size_t csum_and_copy_to_iter(const void *addr, size_t bytes, __wsum *csum,
 			     struct iov_iter *i)
 {
···
 	iterate_and_advance(i, bytes, v, ({
 		int err = 0;
 		next = csum_and_copy_to_user((from += v.iov_len) - v.iov_len,
-					     v.iov_base, 
+					     v.iov_base,
 					     v.iov_len, 0, &err);
 		if (!err) {
 			sum = csum_block_add(sum, next, off);

net/atm/common.c

···
 		goto out;
 	skb->dev = NULL; /* for paths shared with net_device interfaces */
 	ATM_SKB(skb)->atm_options = vcc->atm_options;
-	if (copy_from_iter(skb_put(skb, size), size, &m->msg_iter) != size) {
+	if (!copy_from_iter_full(skb_put(skb, size), size, &m->msg_iter)) {
 		kfree_skb(skb);
 		error = -EFAULT;
 		goto out;

net/bluetooth/l2cap_core.c

···
 	struct sk_buff **frag;
 	int sent = 0;
 
-	if (copy_from_iter(skb_put(skb, count), count, &msg->msg_iter) != count)
+	if (!copy_from_iter_full(skb_put(skb, count), count, &msg->msg_iter))
 		return -EFAULT;
 
 	sent += count;
···
 
 		*frag = tmp;
 
-		if (copy_from_iter(skb_put(*frag, count), count,
-				   &msg->msg_iter) != count)
+		if (!copy_from_iter_full(skb_put(*frag, count), count,
+				   &msg->msg_iter))
 			return -EFAULT;
 
 		sent += count;

net/ipv4/ip_output.c

···
 	struct msghdr *msg = from;
 
 	if (skb->ip_summed == CHECKSUM_PARTIAL) {
-		if (copy_from_iter(to, len, &msg->msg_iter) != len)
+		if (!copy_from_iter_full(to, len, &msg->msg_iter))
 			return -EFAULT;
 	} else {
 		__wsum csum = 0;
-		if (csum_and_copy_from_iter(to, len, &csum, &msg->msg_iter) != len)
+		if (!csum_and_copy_from_iter_full(to, len, &csum, &msg->msg_iter))
 			return -EFAULT;
 		skb->csum = csum_block_add(skb->csum, csum, odd);
 	}

net/ipv4/ping.c

···
 		fraglen -= sizeof(struct icmphdr);
 		if (fraglen < 0)
 			BUG();
-		if (csum_and_copy_from_iter(to + sizeof(struct icmphdr),
+		if (!csum_and_copy_from_iter_full(to + sizeof(struct icmphdr),
 			    fraglen, &pfh->wcheck,
-			    &pfh->msg->msg_iter) != fraglen)
+			    &pfh->msg->msg_iter))
 			return -EFAULT;
 	} else if (offset < sizeof(struct icmphdr)) {
 			BUG();
 	} else {
-		if (csum_and_copy_from_iter(to, fraglen, &pfh->wcheck,
-					    &pfh->msg->msg_iter) != fraglen)
+		if (!csum_and_copy_from_iter_full(to, fraglen, &pfh->wcheck,
+					    &pfh->msg->msg_iter))
 			return -EFAULT;
 	}
 

net/packet/af_packet.c

···
 static int packet_snd_vnet_parse(struct msghdr *msg, size_t *len,
 				 struct virtio_net_hdr *vnet_hdr)
 {
-	int n;
-
 	if (*len < sizeof(*vnet_hdr))
 		return -EINVAL;
 	*len -= sizeof(*vnet_hdr);
 
-	n = copy_from_iter(vnet_hdr, sizeof(*vnet_hdr), &msg->msg_iter);
-	if (n != sizeof(*vnet_hdr))
+	if (!copy_from_iter_full(vnet_hdr, sizeof(*vnet_hdr), &msg->msg_iter))
 		return -EFAULT;
 
 	return __packet_snd_vnet_parse(vnet_hdr, *len);

net/tipc/msg.c

···
 		__skb_queue_tail(list, skb);
 		skb_copy_to_linear_data(skb, mhdr, mhsz);
 		pktpos = skb->data + mhsz;
-		if (copy_from_iter(pktpos, dsz, &m->msg_iter) == dsz)
+		if (copy_from_iter_full(pktpos, dsz, &m->msg_iter))
 			return dsz;
 		rc = -EFAULT;
 		goto error;
···
 		if (drem < pktrem)
 			pktrem = drem;
 
-		if (copy_from_iter(pktpos, pktrem, &m->msg_iter) != pktrem) {
+		if (!copy_from_iter_full(pktpos, pktrem, &m->msg_iter)) {
 			rc = -EFAULT;
 			goto error;
 		}

security/keys/keyctl.c

···
 		}
 
 		ret = -EFAULT;
-		if (copy_from_iter(payload, plen, from) != plen)
+		if (!copy_from_iter_full(payload, plen, from))
 			goto error2;
 	}