1 files changed, 157 insertions, 142 deletions

diff --git a/fs/btrfs/send.c b/fs/btrfs/send.c
index eb6537a08c1b..6528aa662181 100644
--- a/fs/btrfs/send.c
+++ b/fs/btrfs/send.c
@@ -360,10 +360,13 @@ static int fs_path_ensure_buf(struct fs_path *p, int len)
 	/*
 	 * First time the inline_buf does not suffice
 	 */
-	if (p->buf == p->inline_buf)
+	if (p->buf == p->inline_buf) {
 		tmp_buf = kmalloc(len, GFP_NOFS);
-	else
+		if (tmp_buf)
+			memcpy(tmp_buf, p->buf, old_buf_len);
+	} else {
 		tmp_buf = krealloc(p->buf, len, GFP_NOFS);
+	}
 	if (!tmp_buf)
 		return -ENOMEM;
 	p->buf = tmp_buf;
@@ -972,7 +975,7 @@ static int iterate_dir_item(struct btrfs_root *root, struct btrfs_path *path,
 	struct btrfs_dir_item *di;
 	struct btrfs_key di_key;
 	char *buf = NULL;
-	const int buf_len = PATH_MAX;
+	int buf_len;
 	u32 name_len;
 	u32 data_len;
 	u32 cur;
@@ -982,6 +985,11 @@ static int iterate_dir_item(struct btrfs_root *root, struct btrfs_path *path,
 	int num;
 	u8 type;
 
+	if (found_key->type == BTRFS_XATTR_ITEM_KEY)
+		buf_len = BTRFS_MAX_XATTR_SIZE(root);
+	else
+		buf_len = PATH_MAX;
+
 	buf = kmalloc(buf_len, GFP_NOFS);
 	if (!buf) {
 		ret = -ENOMEM;
@@ -1003,12 +1011,23 @@ static int iterate_dir_item(struct btrfs_root *root, struct btrfs_path *path,
 		type = btrfs_dir_type(eb, di);
 		btrfs_dir_item_key_to_cpu(eb, di, &di_key);
 
-		/*
-		 * Path too long
-		 */
-		if (name_len + data_len > buf_len) {
-			ret = -ENAMETOOLONG;
-			goto out;
+		if (type == BTRFS_FT_XATTR) {
+			if (name_len > XATTR_NAME_MAX) {
+				ret = -ENAMETOOLONG;
+				goto out;
+			}
+			if (name_len + data_len > buf_len) {
+				ret = -E2BIG;
+				goto out;
+			}
+		} else {
+			/*
+			 * Path too long
+			 */
+			if (name_len + data_len > buf_len) {
+				ret = -ENAMETOOLONG;
+				goto out;
+			}
 		}
 
 		read_extent_buffer(eb, buf, (unsigned long)(di + 1),
@@ -1346,7 +1365,7 @@ static int find_extent_clone(struct send_ctx *sctx,
 		ret = -EIO;
 		btrfs_err(sctx->send_root->fs_info, "did not find backref in "
 				"send_root. inode=%llu, offset=%llu, "
-				"disk_byte=%llu found extent=%llu\n",
+				"disk_byte=%llu found extent=%llu",
 				ino, data_offset, disk_byte, found_key.objectid);
 		goto out;
 	}
@@ -1625,6 +1644,10 @@ static int lookup_dir_item_inode(struct btrfs_root *root,
 		goto out;
 	}
 	btrfs_dir_item_key_to_cpu(path->nodes[0], di, &key);
+	if (key.type == BTRFS_ROOT_ITEM_KEY) {
+		ret = -ENOENT;
+		goto out;
+	}
 	*found_inode = key.objectid;
 	*found_type = btrfs_dir_type(path->nodes[0], di);
 
@@ -1668,7 +1691,7 @@ static int get_first_ref(struct btrfs_root *root, u64 ino,
 		goto out;
 	}
 
-	if (key.type == BTRFS_INODE_REF_KEY) {
+	if (found_key.type == BTRFS_INODE_REF_KEY) {
 		struct btrfs_inode_ref *iref;
 		iref = btrfs_item_ptr(path->nodes[0], path->slots[0],
 				      struct btrfs_inode_ref);
@@ -1690,10 +1713,12 @@ static int get_first_ref(struct btrfs_root *root, u64 ino,
 		goto out;
 	btrfs_release_path(path);
 
-	ret = get_inode_info(root, parent_dir, NULL, dir_gen, NULL, NULL,
-			NULL, NULL);
-	if (ret < 0)
-		goto out;
+	if (dir_gen) {
+		ret = get_inode_info(root, parent_dir, NULL, dir_gen, NULL,
+				     NULL, NULL, NULL);
+		if (ret < 0)
+			goto out;
+	}
 
 	*dir = parent_dir;
 
@@ -1709,13 +1734,12 @@ static int is_first_ref(struct btrfs_root *root,
 	int ret;
 	struct fs_path *tmp_name;
 	u64 tmp_dir;
-	u64 tmp_dir_gen;
 
 	tmp_name = fs_path_alloc();
 	if (!tmp_name)
 		return -ENOMEM;
 
-	ret = get_first_ref(root, ino, &tmp_dir, &tmp_dir_gen, tmp_name);
+	ret = get_first_ref(root, ino, &tmp_dir, NULL, tmp_name);
 	if (ret < 0)
 		goto out;
 
@@ -2026,7 +2050,6 @@ static int __get_cur_name_and_parent(struct send_ctx *sctx,
 {
 	int ret;
 	int nce_ret;
-	struct btrfs_path *path = NULL;
 	struct name_cache_entry *nce = NULL;
 
 	/*
@@ -2052,10 +2075,6 @@ static int __get_cur_name_and_parent(struct send_ctx *sctx,
 		}
 	}
 
-	path = alloc_path_for_send();
-	if (!path)
-		return -ENOMEM;
-
 	/*
 	 * If the inode is not existent yet, add the orphan name and return 1.
 	 * This should only happen for the parent dir that we determine in
@@ -2131,7 +2150,6 @@ out_cache:
 	name_cache_clean_unused(sctx);
 
 out:
-	btrfs_free_path(path);
 	return ret;
 }
 
@@ -2942,7 +2960,9 @@ static void free_waiting_dir_move(struct send_ctx *sctx,
 static int add_pending_dir_move(struct send_ctx *sctx,
 				u64 ino,
 				u64 ino_gen,
-				u64 parent_ino)
+				u64 parent_ino,
+				struct list_head *new_refs,
+				struct list_head *deleted_refs)
 {
 	struct rb_node **p = &sctx->pending_dir_moves.rb_node;
 	struct rb_node *parent = NULL;
@@ -2974,12 +2994,12 @@ static int add_pending_dir_move(struct send_ctx *sctx,
 		}
 	}
 
-	list_for_each_entry(cur, &sctx->deleted_refs, list) {
+	list_for_each_entry(cur, deleted_refs, list) {
 		ret = dup_ref(cur, &pm->update_refs);
 		if (ret < 0)
 			goto out;
 	}
-	list_for_each_entry(cur, &sctx->new_refs, list) {
+	list_for_each_entry(cur, new_refs, list) {
 		ret = dup_ref(cur, &pm->update_refs);
 		if (ret < 0)
 			goto out;
@@ -3022,6 +3042,48 @@ static struct pending_dir_move *get_pending_dir_moves(struct send_ctx *sctx,
 	return NULL;
 }
 
+static int path_loop(struct send_ctx *sctx, struct fs_path *name,
+		     u64 ino, u64 gen, u64 *ancestor_ino)
+{
+	int ret = 0;
+	u64 parent_inode = 0;
+	u64 parent_gen = 0;
+	u64 start_ino = ino;
+
+	*ancestor_ino = 0;
+	while (ino != BTRFS_FIRST_FREE_OBJECTID) {
+		fs_path_reset(name);
+
+		if (is_waiting_for_rm(sctx, ino))
+			break;
+		if (is_waiting_for_move(sctx, ino)) {
+			if (*ancestor_ino == 0)
+				*ancestor_ino = ino;
+			ret = get_first_ref(sctx->parent_root, ino,
+					    &parent_inode, &parent_gen, name);
+		} else {
+			ret = __get_cur_name_and_parent(sctx, ino, gen,
+							&parent_inode,
+							&parent_gen, name);
+			if (ret > 0) {
+				ret = 0;
+				break;
+			}
+		}
+		if (ret < 0)
+			break;
+		if (parent_inode == start_ino) {
+			ret = 1;
+			if (*ancestor_ino == 0)
+				*ancestor_ino = ino;
+			break;
+		}
+		ino = parent_inode;
+		gen = parent_gen;
+	}
+	return ret;
+}
+
 static int apply_dir_move(struct send_ctx *sctx, struct pending_dir_move *pm)
 {
 	struct fs_path *from_path = NULL;
@@ -3033,6 +3095,7 @@ static int apply_dir_move(struct send_ctx *sctx, struct pending_dir_move *pm)
 	struct waiting_dir_move *dm = NULL;
 	u64 rmdir_ino = 0;
 	int ret;
+	u64 ancestor = 0;
 
 	name = fs_path_alloc();
 	from_path = fs_path_alloc();
@@ -3051,34 +3114,33 @@ static int apply_dir_move(struct send_ctx *sctx, struct pending_dir_move *pm)
 	if (ret < 0)
 		goto out;
 
-	if (parent_ino == sctx->cur_ino) {
-		/* child only renamed, not moved */
-		ASSERT(parent_gen == sctx->cur_inode_gen);
-		ret = get_cur_path(sctx, sctx->cur_ino, sctx->cur_inode_gen,
-				   from_path);
-		if (ret < 0)
-			goto out;
-		ret = fs_path_add_path(from_path, name);
-		if (ret < 0)
-			goto out;
-	} else {
-		/* child moved and maybe renamed too */
-		sctx->send_progress = pm->ino;
-		ret = get_cur_path(sctx, pm->ino, pm->gen, from_path);
+	ret = get_cur_path(sctx, parent_ino, parent_gen,
+			   from_path);
+	if (ret < 0)
+		goto out;
+	ret = fs_path_add_path(from_path, name);
+	if (ret < 0)
+		goto out;
+
+	sctx->send_progress = sctx->cur_ino + 1;
+	ret = path_loop(sctx, name, pm->ino, pm->gen, &ancestor);
+	if (ret) {
+		LIST_HEAD(deleted_refs);
+		ASSERT(ancestor > BTRFS_FIRST_FREE_OBJECTID);
+		ret = add_pending_dir_move(sctx, pm->ino, pm->gen, ancestor,
+					   &pm->update_refs, &deleted_refs);
 		if (ret < 0)
 			goto out;
-	}
-
-	fs_path_free(name);
-	name = NULL;
-
-	to_path = fs_path_alloc();
-	if (!to_path) {
-		ret = -ENOMEM;
+		if (rmdir_ino) {
+			dm = get_waiting_dir_move(sctx, pm->ino);
+			ASSERT(dm);
+			dm->rmdir_ino = rmdir_ino;
+		}
 		goto out;
 	}
-
-	sctx->send_progress = sctx->cur_ino + 1;
+	fs_path_reset(name);
+	to_path = name;
+	name = NULL;
 	ret = get_cur_path(sctx, pm->ino, pm->gen, to_path);
 	if (ret < 0)
 		goto out;
@@ -3202,127 +3264,74 @@ out:
 static int wait_for_parent_move(struct send_ctx *sctx,
 				struct recorded_ref *parent_ref)
 {
-	int ret;
+	int ret = 0;
 	u64 ino = parent_ref->dir;
 	u64 parent_ino_before, parent_ino_after;
-	u64 old_gen;
 	struct fs_path *path_before = NULL;
 	struct fs_path *path_after = NULL;
 	int len1, len2;
-	int register_upper_dirs;
-	u64 gen;
-
-	if (is_waiting_for_move(sctx, ino))
-		return 1;
-
-	if (parent_ref->dir <= sctx->cur_ino)
-		return 0;
-
-	ret = get_inode_info(sctx->parent_root, ino, NULL, &old_gen,
-			     NULL, NULL, NULL, NULL);
-	if (ret == -ENOENT)
-		return 0;
-	else if (ret < 0)
-		return ret;
-
-	if (parent_ref->dir_gen != old_gen)
-		return 0;
-
-	path_before = fs_path_alloc();
-	if (!path_before)
-		return -ENOMEM;
-
-	ret = get_first_ref(sctx->parent_root, ino, &parent_ino_before,
-			    NULL, path_before);
-	if (ret == -ENOENT) {
-		ret = 0;
-		goto out;
-	} else if (ret < 0) {
-		goto out;
-	}
 
 	path_after = fs_path_alloc();
-	if (!path_after) {
+	path_before = fs_path_alloc();
+	if (!path_after || !path_before) {
 		ret = -ENOMEM;
 		goto out;
 	}
 
-	ret = get_first_ref(sctx->send_root, ino, &parent_ino_after,
-			    &gen, path_after);
-	if (ret == -ENOENT) {
-		ret = 0;
-		goto out;
-	} else if (ret < 0) {
-		goto out;
-	}
-
-	len1 = fs_path_len(path_before);
-	len2 = fs_path_len(path_after);
-	if (parent_ino_before != parent_ino_after || len1 != len2 ||
-	     memcmp(path_before->start, path_after->start, len1)) {
-		ret = 1;
-		goto out;
-	}
-	ret = 0;
-
 	/*
-	 * Ok, our new most direct ancestor has a higher inode number but
-	 * wasn't moved/renamed. So maybe some of the new ancestors higher in
-	 * the hierarchy have an higher inode number too *and* were renamed
-	 * or moved - in this case we need to wait for the ancestor's rename
-	 * or move operation before we can do the move/rename for the current
-	 * inode.
+	 * Our current directory inode may not yet be renamed/moved because some
+	 * ancestor (immediate or not) has to be renamed/moved first. So find if
+	 * such ancestor exists and make sure our own rename/move happens after
+	 * that ancestor is processed.
 	 */
-	register_upper_dirs = 0;
-	ino = parent_ino_after;
-again:
-	while ((ret == 0 || register_upper_dirs) && ino > sctx->cur_ino) {
-		u64 parent_gen;
+	while (ino > BTRFS_FIRST_FREE_OBJECTID) {
+		if (is_waiting_for_move(sctx, ino)) {
+			ret = 1;
+			break;
+		}
 
 		fs_path_reset(path_before);
 		fs_path_reset(path_after);
 
 		ret = get_first_ref(sctx->send_root, ino, &parent_ino_after,
-				    &parent_gen, path_after);
+				    NULL, path_after);
 		if (ret < 0)
 			goto out;
 		ret = get_first_ref(sctx->parent_root, ino, &parent_ino_before,
 				    NULL, path_before);
-		if (ret == -ENOENT) {
-			ret = 0;
-			break;
-		} else if (ret < 0) {
+		if (ret < 0 && ret != -ENOENT) {
 			goto out;
+		} else if (ret == -ENOENT) {
+			ret = 1;
+			break;
 		}
 
 		len1 = fs_path_len(path_before);
 		len2 = fs_path_len(path_after);
-		if (parent_ino_before != parent_ino_after || len1 != len2 ||
-		    memcmp(path_before->start, path_after->start, len1)) {
+		if (ino > sctx->cur_ino &&
+		    (parent_ino_before != parent_ino_after || len1 != len2 ||
+		     memcmp(path_before->start, path_after->start, len1))) {
 			ret = 1;
-			if (register_upper_dirs) {
-				break;
-			} else {
-				register_upper_dirs = 1;
-				ino = parent_ref->dir;
-				gen = parent_ref->dir_gen;
-				goto again;
-			}
-		} else if (register_upper_dirs) {
-			ret = add_pending_dir_move(sctx, ino, gen,
-						   parent_ino_after);
-			if (ret < 0 && ret != -EEXIST)
-				goto out;
+			break;
 		}
-
 		ino = parent_ino_after;
-		gen = parent_gen;
 	}
 
 out:
 	fs_path_free(path_before);
 	fs_path_free(path_after);
 
+	if (ret == 1) {
+		ret = add_pending_dir_move(sctx,
+					   sctx->cur_ino,
+					   sctx->cur_inode_gen,
+					   ino,
+					   &sctx->new_refs,
+					   &sctx->deleted_refs);
+		if (!ret)
+			ret = 1;
+	}
+
 	return ret;
 }
 
@@ -3483,10 +3492,6 @@ verbose_printk("btrfs: process_recorded_refs %llu\n", sctx->cur_ino);
 				if (ret < 0)
 					goto out;
 				if (ret) {
-					ret = add_pending_dir_move(sctx,
-							   sctx->cur_ino,
-							   sctx->cur_inode_gen,
-							   cur->dir);
 					*pending_move = 1;
 				} else {
 					ret = send_rename(sctx, valid_path,
@@ -5487,7 +5492,7 @@ static void btrfs_root_dec_send_in_progress(struct btrfs_root* root)
 	 */
 	if (root->send_in_progress < 0)
 		btrfs_err(root->fs_info,
-			"send_in_progres unbalanced %d root %llu\n",
+			"send_in_progres unbalanced %d root %llu",
 			root->send_in_progress, root->root_key.objectid);
 	spin_unlock(&root->root_item_lock);
 }
@@ -5515,7 +5520,7 @@ long btrfs_ioctl_send(struct file *mnt_file, void __user *arg_)
 
 	/*
 	 * The subvolume must remain read-only during send, protect against
-	 * making it RW.
+	 * making it RW. This also protects against deletion.
 	 */
 	spin_lock(&send_root->root_item_lock);
 	send_root->send_in_progress++;
@@ -5575,6 +5580,15 @@ long btrfs_ioctl_send(struct file *mnt_file, void __user *arg_)
 	}
 
 	sctx->send_root = send_root;
+	/*
+	 * Unlikely but possible, if the subvolume is marked for deletion but
+	 * is slow to remove the directory entry, send can still be started
+	 */
+	if (btrfs_root_dead(sctx->send_root)) {
+		ret = -EPERM;
+		goto out;
+	}
+
 	sctx->clone_roots_cnt = arg->clone_sources_count;
 
 	sctx->send_max_size = BTRFS_SEND_BUF_SIZE;
@@ -5664,7 +5678,8 @@ long btrfs_ioctl_send(struct file *mnt_file, void __user *arg_)
 
 		spin_lock(&sctx->parent_root->root_item_lock);
 		sctx->parent_root->send_in_progress++;
-		if (!btrfs_root_readonly(sctx->parent_root)) {
+		if (!btrfs_root_readonly(sctx->parent_root) ||
+				btrfs_root_dead(sctx->parent_root)) {
 			spin_unlock(&sctx->parent_root->root_item_lock);
 			srcu_read_unlock(&fs_info->subvol_srcu, index);
 			ret = -EPERM;