ext4: use journal inode to determine journal overhead

When a file system contains an internal journal that has not been
loaded, use the journal inode's i_size field to determine its
contribution to the file system's overhead.  (The journal's j_maxlen
field is normally used to determine its size, but it's unavailable when
the journal has not been loaded.)

Signed-off-by: Eric Whitney <enwlinux@gmail.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
This commit is contained in:
Eric Whitney 2016-09-30 02:08:49 -04:00 committed by Theodore Ts'o
parent c6cb7e776a
commit 3c816ded78
1 changed files with 17 additions and 2 deletions

View File

@ -3210,6 +3210,8 @@ int ext4_calculate_overhead(struct super_block *sb)
{
struct ext4_sb_info *sbi = EXT4_SB(sb);
struct ext4_super_block *es = sbi->s_es;
struct inode *j_inode;
unsigned int j_blocks, j_inum = le32_to_cpu(es->s_journal_inum);
ext4_group_t i, ngroups = ext4_get_groups_count(sb);
ext4_fsblk_t overhead = 0;
char *buf = (char *) get_zeroed_page(GFP_NOFS);
@ -3240,10 +3242,23 @@ int ext4_calculate_overhead(struct super_block *sb)
memset(buf, 0, PAGE_SIZE);
cond_resched();
}
/* Add the internal journal blocks as well */
/*
* Add the internal journal blocks whether the journal has been
* loaded or not
*/
if (sbi->s_journal && !sbi->journal_bdev)
overhead += EXT4_NUM_B2C(sbi, sbi->s_journal->j_maxlen);
else if (ext4_has_feature_journal(sb) && !sbi->s_journal) {
j_inode = ext4_get_journal_inode(sb, j_inum);
if (j_inode) {
j_blocks = j_inode->i_size >> sb->s_blocksize_bits;
overhead += EXT4_NUM_B2C(sbi, j_blocks);
iput(j_inode);
} else {
ext4_msg(sb, KERN_ERR, "can't get journal size");
}
}
sbi->s_overhead = overhead;
smp_wmb();
free_page((unsigned long) buf);