/*
   * Copyright (C) 2013 Fusion IO.  All rights reserved.
   *
   * This program is free software; you can redistribute it and/or
   * modify it under the terms of the GNU General Public
   * License v2 as published by the Free Software Foundation.
   *
   * This program is distributed in the hope that it will be useful,
   * but WITHOUT ANY WARRANTY; without even the implied warranty of
   * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
   * General Public License for more details.
   *
   * You should have received a copy of the GNU General Public
   * License along with this program; if not, write to the
   * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
   * Boston, MA 021110-1307, USA.
   */
  
  #include <linux/slab.h>
  #include "btrfs-tests.h"
  #include "../ctree.h"
  #include "../extent_io.h"
  #include "../disk-io.h"
  
  static int test_btrfs_split_item(void)
  {
  	struct btrfs_path *path;
  	struct btrfs_root *root;
  	struct extent_buffer *eb;
  	struct btrfs_item *item;
  	char *value = "mary had a little lamb";
  	char *split1 = "mary had a little";
  	char *split2 = " lamb";
  	char *split3 = "mary";
  	char *split4 = " had a little";
  	char buf[32];
  	struct btrfs_key key;
  	u32 value_len = strlen(value);
  	int ret = 0;
  
  	test_msg("Running btrfs_split_item tests
  ");
  
  	root = btrfs_alloc_dummy_root();
  	if (IS_ERR(root)) {
  		test_msg("Could not allocate root
  ");
  		return PTR_ERR(root);
  	}
  
  	path = btrfs_alloc_path();
  	if (!path) {
  		test_msg("Could not allocate path
  ");
  		kfree(root);
  		return -ENOMEM;
  	}
  
  	path->nodes[0] = eb = alloc_dummy_extent_buffer(0, 4096);
  	if (!eb) {
  		test_msg("Could not allocate dummy buffer
  ");
  		ret = -ENOMEM;
  		goto out;
  	}
  	path->slots[0] = 0;
  
  	key.objectid = 0;
  	key.type = BTRFS_EXTENT_CSUM_KEY;
  	key.offset = 0;
  
  	setup_items_for_insert(root, path, &key, &value_len, value_len,
  			       value_len + sizeof(struct btrfs_item), 1);
  	item = btrfs_item_nr(0);
  	write_extent_buffer(eb, value, btrfs_item_ptr_offset(eb, 0),
  			    value_len);
  
  	key.offset = 3;
  
  	/*
  	 * Passing NULL trans here should be safe because we have plenty of
  	 * space in this leaf to split the item without having to split the
  	 * leaf.
  	 */
  	ret = btrfs_split_item(NULL, root, path, &key, 17);
  	if (ret) {
  		test_msg("Split item failed %d
  ", ret);
  		goto out;
  	}
  
  	/*
  	 * Read the first slot, it should have the original key and contain only
  	 * 'mary had a little'
  	 */
  	btrfs_item_key_to_cpu(eb, &key, 0);
  	if (key.objectid != 0 || key.type != BTRFS_EXTENT_CSUM_KEY ||
  	    key.offset != 0) {
  		test_msg("Invalid key at slot 0
  ");
  		ret = -EINVAL;
  		goto out;
  	}
  
  	item = btrfs_item_nr(0);
  	if (btrfs_item_size(eb, item) != strlen(split1)) {
  		test_msg("Invalid len in the first split
  ");
  		ret = -EINVAL;
  		goto out;
  	}
  
  	read_extent_buffer(eb, buf, btrfs_item_ptr_offset(eb, 0),
  			   strlen(split1));
  	if (memcmp(buf, split1, strlen(split1))) {
  		test_msg("Data in the buffer doesn't match what it should "
  			 "in the first split have='%.*s' want '%s'
  ",
  			 (int)strlen(split1), buf, split1);
  		ret = -EINVAL;
  		goto out;
  	}
  
  	btrfs_item_key_to_cpu(eb, &key, 1);
  	if (key.objectid != 0 || key.type != BTRFS_EXTENT_CSUM_KEY ||
  	    key.offset != 3) {
  		test_msg("Invalid key at slot 1
  ");
  		ret = -EINVAL;
  		goto out;
  	}
  
  	item = btrfs_item_nr(1);
  	if (btrfs_item_size(eb, item) != strlen(split2)) {
  		test_msg("Invalid len in the second split
  ");
  		ret = -EINVAL;
  		goto out;
  	}
  
  	read_extent_buffer(eb, buf, btrfs_item_ptr_offset(eb, 1),
  			   strlen(split2));
  	if (memcmp(buf, split2, strlen(split2))) {
  		test_msg("Data in the buffer doesn't match what it should "
  			 "in the second split
  ");
  		ret = -EINVAL;
  		goto out;
  	}
  
  	key.offset = 1;
  	/* Do it again so we test memmoving the other items in the leaf */
  	ret = btrfs_split_item(NULL, root, path, &key, 4);
  	if (ret) {
  		test_msg("Second split item failed %d
  ", ret);
  		goto out;
  	}
  
  	btrfs_item_key_to_cpu(eb, &key, 0);
  	if (key.objectid != 0 || key.type != BTRFS_EXTENT_CSUM_KEY ||
  	    key.offset != 0) {
  		test_msg("Invalid key at slot 0
  ");
  		ret = -EINVAL;
  		goto out;
  	}
  
  	item = btrfs_item_nr(0);
  	if (btrfs_item_size(eb, item) != strlen(split3)) {
  		test_msg("Invalid len in the first split
  ");
  		ret = -EINVAL;
  		goto out;
  	}
  
  	read_extent_buffer(eb, buf, btrfs_item_ptr_offset(eb, 0),
  			   strlen(split3));
  	if (memcmp(buf, split3, strlen(split3))) {
  		test_msg("Data in the buffer doesn't match what it should "
  			 "in the third split");
  		ret = -EINVAL;
  		goto out;
  	}
  
  	btrfs_item_key_to_cpu(eb, &key, 1);
  	if (key.objectid != 0 || key.type != BTRFS_EXTENT_CSUM_KEY ||
  	    key.offset != 1) {
  		test_msg("Invalid key at slot 1
  ");
  		ret = -EINVAL;
  		goto out;
  	}
  
  	item = btrfs_item_nr(1);
  	if (btrfs_item_size(eb, item) != strlen(split4)) {
  		test_msg("Invalid len in the second split
  ");
  		ret = -EINVAL;
  		goto out;
  	}
  
  	read_extent_buffer(eb, buf, btrfs_item_ptr_offset(eb, 1),
  			   strlen(split4));
  	if (memcmp(buf, split4, strlen(split4))) {
  		test_msg("Data in the buffer doesn't match what it should "
  			 "in the fourth split
  ");
  		ret = -EINVAL;
  		goto out;
  	}
  
  	btrfs_item_key_to_cpu(eb, &key, 2);
  	if (key.objectid != 0 || key.type != BTRFS_EXTENT_CSUM_KEY ||
  	    key.offset != 3) {
  		test_msg("Invalid key at slot 2
  ");
  		ret = -EINVAL;
  		goto out;
  	}
  
  	item = btrfs_item_nr(2);
  	if (btrfs_item_size(eb, item) != strlen(split2)) {
  		test_msg("Invalid len in the second split
  ");
  		ret = -EINVAL;
  		goto out;
  	}
  
  	read_extent_buffer(eb, buf, btrfs_item_ptr_offset(eb, 2),
  			   strlen(split2));
  	if (memcmp(buf, split2, strlen(split2))) {
  		test_msg("Data in the buffer doesn't match what it should "
  			 "in the last chunk
  ");
  		ret = -EINVAL;
  		goto out;
  	}
  out:
  	btrfs_free_path(path);
  	kfree(root);
  	return ret;
  }
  
  int btrfs_test_extent_buffer_operations(void)
  {
  	test_msg("Running extent buffer operation tests");
  	return test_btrfs_split_item();
  }