Commit db69e0eb authored by Chris Mason's avatar Chris Mason
Browse files

Btrfs: Init address_space->writeback_index properly 



The writeback_index field is used by write_cache_pages to pick up where
writeback on a given inode left off.  But, it is never set to a sane
value, so writeback can often start at a random offset in the file.

Kernels 2.6.28 and higher will have this fixed, but for everyone else,
we also fill in the value in btrfs.

Signed-off-by: default avatarChris Mason <chris.mason@oracle.com>
parent 2db04966

fs/btrfs/inode.c

+4 −0
Original line number Diff line number Diff line
@@ -1833,6 +1833,7 @@ static int btrfs_init_locked_inode(struct inode *inode, void *p) 
	inode->i_ino = args->ino;

	BTRFS_I(inode)->root = args->root;

	BTRFS_I(inode)->delalloc_bytes = 0;

	inode->i_mapping->writeback_index = 0;

	BTRFS_I(inode)->disk_i_size = 0;

	BTRFS_I(inode)->index_cnt = (u64)-1;

	extent_map_tree_init(&BTRFS_I(inode)->extent_tree, GFP_NOFS);
@@ -2239,6 +2240,7 @@ static struct inode *btrfs_new_inode(struct btrfs_trans_handle *trans, 
	mutex_init(&BTRFS_I(inode)->csum_mutex);

	mutex_init(&BTRFS_I(inode)->extent_mutex);

	BTRFS_I(inode)->delalloc_bytes = 0;

	inode->i_mapping->writeback_index = 0;

	BTRFS_I(inode)->disk_i_size = 0;

	BTRFS_I(inode)->root = root;
@@ -2486,6 +2488,7 @@ static int btrfs_create(struct inode *dir, struct dentry *dentry, 
		mutex_init(&BTRFS_I(inode)->extent_mutex);

		BTRFS_I(inode)->delalloc_bytes = 0;

		BTRFS_I(inode)->disk_i_size = 0;

		inode->i_mapping->writeback_index = 0;

		BTRFS_I(inode)->io_tree.ops = &btrfs_extent_io_ops;

		btrfs_ordered_inode_tree_init(&BTRFS_I(inode)->ordered_tree);

	}
@@ -3549,6 +3552,7 @@ static int btrfs_symlink(struct inode *dir, struct dentry *dentry, 
		mutex_init(&BTRFS_I(inode)->extent_mutex);

		BTRFS_I(inode)->delalloc_bytes = 0;

		BTRFS_I(inode)->disk_i_size = 0;

		inode->i_mapping->writeback_index = 0;

		BTRFS_I(inode)->io_tree.ops = &btrfs_extent_io_ops;

		btrfs_ordered_inode_tree_init(&BTRFS_I(inode)->ordered_tree);

	}

CRA Git | Maintained and supported by SUSTech CRA and CCSE