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Commit a2dc52b5 authored by Theodore Ts'o's avatar Theodore Ts'o
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ext4: Add BUG_ON debugging checks to noalloc_get_block_write() 



Enforce that noalloc_get_block_write() is only called to map one block
at a time, and that it always is successful in finding a mapping for
given an inode's logical block block number if it is called with
create == 1.

Signed-off-by: default avatar"Theodore Ts'o" <tytso@mit.edu>
parent b920c755

fs/ext4/inode.c

+3 −0
Original line number Original line Diff line number Diff line
@@ -2433,11 +2433,14 @@ static int noalloc_get_block_write(struct inode *inode, sector_t iblock, 
	int ret = 0;

	int ret = 0;

	unsigned max_blocks = bh_result->b_size >> inode->i_blkbits;

	unsigned max_blocks = bh_result->b_size >> inode->i_blkbits;





	BUG_ON(bh_result->b_size != inode->i_sb->s_blocksize);



	/*

	/*

	 * we don't want to do block allocation in writepage

	 * we don't want to do block allocation in writepage

	 * so call get_block_wrap with create = 0

	 * so call get_block_wrap with create = 0

	 */

	 */

	ret = ext4_get_blocks(NULL, inode, iblock, max_blocks, bh_result, 0);

	ret = ext4_get_blocks(NULL, inode, iblock, max_blocks, bh_result, 0);

	BUG_ON(create && ret == 0);

	if (ret > 0) {

	if (ret > 0) {

		bh_result->b_size = (ret << inode->i_blkbits);

		bh_result->b_size = (ret << inode->i_blkbits);

		ret = 0;

		ret = 0;