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	 13a8a7c8c4
			
		
	
	
		13a8a7c8c4
		
	
	
	
	
		
			
			The new back reference format does not allow reusing objectid of deleted snapshot/subvol. So we use ++highest_objectid to allocate objectid for new snapshot/subvol. Now we use ++highest_objectid to allocate objectid for both new inode and new snapshot/subvolume, so this patch removes 'find hole' code in btrfs_find_free_objectid. Signed-off-by: Yan Zheng <zheng.yan@oracle.com> Signed-off-by: Chris Mason <chris.mason@oracle.com>
		
			
				
	
	
		
			81 lines
		
	
	
		
			2.1 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			81 lines
		
	
	
		
			2.1 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
| /*
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|  * Copyright (C) 2007 Oracle.  All rights reserved.
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|  *
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|  * This program is free software; you can redistribute it and/or
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|  * modify it under the terms of the GNU General Public
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|  * License v2 as published by the Free Software Foundation.
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|  *
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|  * This program is distributed in the hope that it will be useful,
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|  * but WITHOUT ANY WARRANTY; without even the implied warranty of
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|  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
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|  * General Public License for more details.
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|  *
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|  * You should have received a copy of the GNU General Public
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|  * License along with this program; if not, write to the
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|  * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
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|  * Boston, MA 021110-1307, USA.
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|  */
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| 
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| #include "ctree.h"
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| #include "disk-io.h"
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| #include "transaction.h"
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| 
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| int btrfs_find_highest_inode(struct btrfs_root *root, u64 *objectid)
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| {
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| 	struct btrfs_path *path;
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| 	int ret;
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| 	struct extent_buffer *l;
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| 	struct btrfs_key search_key;
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| 	struct btrfs_key found_key;
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| 	int slot;
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| 
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| 	path = btrfs_alloc_path();
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| 	BUG_ON(!path);
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| 
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| 	search_key.objectid = BTRFS_LAST_FREE_OBJECTID;
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| 	search_key.type = -1;
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| 	search_key.offset = (u64)-1;
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| 	ret = btrfs_search_slot(NULL, root, &search_key, path, 0, 0);
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| 	if (ret < 0)
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| 		goto error;
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| 	BUG_ON(ret == 0);
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| 	if (path->slots[0] > 0) {
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| 		slot = path->slots[0] - 1;
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| 		l = path->nodes[0];
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| 		btrfs_item_key_to_cpu(l, &found_key, slot);
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| 		*objectid = max_t(u64, found_key.objectid,
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| 				  BTRFS_FIRST_FREE_OBJECTID - 1);
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| 	} else {
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| 		*objectid = BTRFS_FIRST_FREE_OBJECTID - 1;
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| 	}
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| 	ret = 0;
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| error:
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| 	btrfs_free_path(path);
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| 	return ret;
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| }
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| 
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| int btrfs_find_free_objectid(struct btrfs_trans_handle *trans,
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| 			     struct btrfs_root *root,
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| 			     u64 dirid, u64 *objectid)
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| {
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| 	int ret;
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| 	mutex_lock(&root->objectid_mutex);
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| 
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| 	if (unlikely(root->highest_objectid < BTRFS_FIRST_FREE_OBJECTID)) {
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| 		ret = btrfs_find_highest_inode(root, &root->highest_objectid);
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| 		if (ret)
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| 			goto out;
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| 	}
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| 
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| 	if (unlikely(root->highest_objectid >= BTRFS_LAST_FREE_OBJECTID)) {
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| 		ret = -ENOSPC;
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| 		goto out;
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| 	}
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| 
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| 	*objectid = ++root->highest_objectid;
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| 	ret = 0;
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| out:
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| 	mutex_unlock(&root->objectid_mutex);
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| 	return ret;
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| }
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