1 /* SPDX-License-Identifier: GPL-2.0 */
3 * linux/fs/ext4/truncate.h
5 * Common inline functions needed for truncate support
9 * Truncate blocks that were not used by write. We have to truncate the
10 * pagecache as well so that corresponding buffers get properly unmapped.
12 static inline void ext4_truncate_failed_write(struct inode *inode)
14 down_write(&EXT4_I(inode)->i_mmap_sem);
15 truncate_inode_pages(inode->i_mapping, inode->i_size);
17 up_write(&EXT4_I(inode)->i_mmap_sem);
21 * Work out how many blocks we need to proceed with the next chunk of a
22 * truncate transaction.
24 static inline unsigned long ext4_blocks_for_truncate(struct inode *inode)
28 needed = inode->i_blocks >> (inode->i_sb->s_blocksize_bits - 9);
30 /* Give ourselves just enough room to cope with inodes in which
31 * i_blocks is corrupt: we've seen disk corruptions in the past
32 * which resulted in random data in an inode which looked enough
33 * like a regular file for ext4 to try to delete it. Things
34 * will go a bit crazy if that happens, but at least we should
35 * try not to panic the whole kernel. */
39 /* But we need to bound the transaction so we don't overflow the
41 if (needed > EXT4_MAX_TRANS_DATA)
42 needed = EXT4_MAX_TRANS_DATA;
44 return EXT4_DATA_TRANS_BLOCKS(inode->i_sb) + needed;