Gh0st
/
linux
mirror of https://github.com/torvalds/linux.git
1
0
Fork 0
Code Issues Packages Projects Releases Wiki Activity

ext4: support large block size in ext4_calculate_overhead() 

ext4_calculate_overhead() used a single page for its bitmap buffer, which
worked fine when PAGE_SIZE >= block size. However, with block size greater
than page size (BS > PS) support, the bitmap can exceed a single page.

To address this, we now use kvmalloc() to allocate memory of the filesystem
block size, to properly support BS > PS.

Suggested-by: Jan Kara <jack@suse.cz>
Signed-off-by: Baokun Li <libaokun1@huawei.com>
Reviewed-by: Zhang Yi <yi.zhang@huawei.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Reviewed-by: Ojaswin Mujoo <ojaswin@linux.ibm.com>
Message-ID: <20251121090654.631996-8-libaokun@huaweicloud.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
This commit is contained in:
Baokun Li 2025-11-21 17:06:37 +08:00 committed by Theodore Ts'o
parent 8611e608a8
commit 6a28b5c990
1 changed files with 3 additions and 3 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

6
fs/ext4/super.c
View File

@ -4191,7 +4191,7 @@ int ext4_calculate_overhead(struct super_block *sb)
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);
char *buf = kvmalloc(sb->s_blocksize, GFP_NOFS | __GFP_ZERO);
if (!buf)
return -ENOMEM;
@ -4216,7 +4216,7 @@ int ext4_calculate_overhead(struct super_block *sb)
blks = count_overhead(sb, i, buf);
overhead += blks;
if (blks)
memset(buf, 0, PAGE_SIZE);
memset(buf, 0, sb->s_blocksize);
cond_resched();
}
@ -4239,7 +4239,7 @@ int ext4_calculate_overhead(struct super_block *sb)
}
sbi->s_overhead = overhead;
smp_wmb();
free_page((unsigned long) buf);
kvfree(buf);
return 0;
}