Orange Pi5 kernel

^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  1) // SPDX-License-Identifier: GPL-2.0
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  2) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  3)  * linux/fs/ext4/truncate.h
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  4)  *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  5)  * Common inline functions needed for truncate support
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  6)  */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  7) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  8) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  9)  * Truncate blocks that were not used by write. We have to truncate the
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 10)  * pagecache as well so that corresponding buffers get properly unmapped.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 11)  */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 12) static inline void ext4_truncate_failed_write(struct inode *inode)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 13) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 14) 	/*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 15) 	 * We don't need to call ext4_break_layouts() because the blocks we
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 16) 	 * are truncating were never visible to userspace.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 17) 	 */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 18) 	down_write(&EXT4_I(inode)->i_mmap_sem);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 19) 	truncate_inode_pages(inode->i_mapping, inode->i_size);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 20) 	ext4_truncate(inode);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 21) 	up_write(&EXT4_I(inode)->i_mmap_sem);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 22) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 23) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 24) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 25)  * Work out how many blocks we need to proceed with the next chunk of a
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 26)  * truncate transaction.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 27)  */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 28) static inline unsigned long ext4_blocks_for_truncate(struct inode *inode)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 29) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 30) 	ext4_lblk_t needed;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 31) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 32) 	needed = inode->i_blocks >> (inode->i_sb->s_blocksize_bits - 9);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 33) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 34) 	/* Give ourselves just enough room to cope with inodes in which
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 35) 	 * i_blocks is corrupt: we've seen disk corruptions in the past
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 36) 	 * which resulted in random data in an inode which looked enough
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 37) 	 * like a regular file for ext4 to try to delete it.  Things
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 38) 	 * will go a bit crazy if that happens, but at least we should
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 39) 	 * try not to panic the whole kernel. */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 40) 	if (needed < 2)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 41) 		needed = 2;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 42) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 43) 	/* But we need to bound the transaction so we don't overflow the
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 44) 	 * journal. */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 45) 	if (needed > EXT4_MAX_TRANS_DATA)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 46) 		needed = EXT4_MAX_TRANS_DATA;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 47) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 48) 	return EXT4_DATA_TRANS_BLOCKS(inode->i_sb) + needed;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 49) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 50)