Commit 707d1a2f authored by Theodore Ts'o's avatar Theodore Ts'o
Browse files

ext4: optimize __ext4_check_dir_entry() 



Make __ext4_check_dir_entry() a bit easier to understand, and reduce
the object size of the function by over 11%.

Signed-off-by: default avatarTheodore Ts'o <tytso@mit.edu>
Link: https://lore.kernel.org/r/20191209004346.38526-1-tytso@mit.edu


Signed-off-by: default avatarTheodore Ts'o <tytso@mit.edu>
parent 109ba779

fs/ext4/dir.c

+4 −5
Original line number Diff line number Diff line
@@ -72,6 +72,7 @@ int __ext4_check_dir_entry(const char *function, unsigned int line, 
	const char *error_msg = NULL;

	const int rlen = ext4_rec_len_from_disk(de->rec_len,

						dir->i_sb->s_blocksize);

	const int next_offset = ((char *) de - buf) + rlen;



	if (unlikely(rlen < EXT4_DIR_REC_LEN(1)))

		error_msg = "rec_len is smaller than minimal";
@@ -79,13 +80,11 @@ int __ext4_check_dir_entry(const char *function, unsigned int line, 
		error_msg = "rec_len % 4 != 0";

	else if (unlikely(rlen < EXT4_DIR_REC_LEN(de->name_len)))

		error_msg = "rec_len is too small for name_len";

	else if (unlikely(((char *) de - buf) + rlen > size))

	else if (unlikely(next_offset > size))

		error_msg = "directory entry overrun";

	else if (unlikely(((char *) de - buf) + rlen >

			  size - EXT4_DIR_REC_LEN(1) &&

			  ((char *) de - buf) + rlen != size)) {

	else if (unlikely(next_offset > size - EXT4_DIR_REC_LEN(1) &&

			  next_offset != size))

		error_msg = "directory entry too close to block end";

	}

	else if (unlikely(le32_to_cpu(de->inode) >

			le32_to_cpu(EXT4_SB(dir->i_sb)->s_es->s_inodes_count)))

		error_msg = "inode out of bounds";

CRA Git | Maintained and supported by SUSTech CRA and CCSE