Commit cab8cbcb authored by Baokun Li's avatar Baokun Li Committed by Theodore Ts'o
Browse files

ext4: enable block size larger than page size 



Since block device (See commit 3c209171 ("block/bdev: enable large
folio support for large logical block sizes")) and page cache (See commit
ab95d23b ("filemap: allocate mapping_min_order folios in the page
cache")) has the ability to have a minimum order when allocating folio,
and ext4 has supported large folio in commit 7ac67301 ("ext4: enable
large folio for regular file"), now add support for block_size > PAGE_SIZE
in ext4.

set_blocksize() -> bdev_validate_blocksize() already validates the block
size, so ext4_load_super() does not need to perform additional checks.
Here we only need to add the FS_LBS bit to fs_flags.

In addition, block sizes larger than the page size are currently supported
only when CONFIG_TRANSPARENT_HUGEPAGE is enabled. To make this explicit,
a blocksize_gt_pagesize entry has been added under /sys/fs/ext4/feature/,
indicating whether bs > ps is supported. This allows mke2fs to check the
interface and determine whether a warning should be issued when formatting
a filesystem with block size larger than the page size.

Suggested-by: default avatarTheodore Ts'o <tytso@mit.edu>
Signed-off-by: default avatarBaokun Li <libaokun1@huawei.com>
Reviewed-by: default avatarZhang Yi <yi.zhang@huawei.com>
Reviewed-by: default avatarJan Kara <jack@suse.cz>
Reviewed-by: default avatarPankaj Raghav <p.raghav@samsung.com>
Reviewed-by: default avatarOjaswin Mujoo <ojaswin@linux.ibm.com>
Message-ID: <20251121090654.631996-25-libaokun@huaweicloud.com>
Signed-off-by: default avatarTheodore Ts'o <tytso@mit.edu>
parent 709f0f1f

fs/ext4/super.c

+2 −1
Original line number Diff line number Diff line
@@ -7453,7 +7453,8 @@ static struct file_system_type ext4_fs_type = { 
	.init_fs_context	= ext4_init_fs_context,

	.parameters		= ext4_param_specs,

	.kill_sb		= ext4_kill_sb,

	.fs_flags		= FS_REQUIRES_DEV | FS_ALLOW_IDMAP | FS_MGTIME,

	.fs_flags		= FS_REQUIRES_DEV | FS_ALLOW_IDMAP | FS_MGTIME |

				  FS_LBS,

};

MODULE_ALIAS_FS("ext4");

fs/ext4/sysfs.c

+6 −0
Original line number Diff line number Diff line
@@ -332,6 +332,9 @@ EXT4_ATTR_FEATURE(fast_commit); 
#if IS_ENABLED(CONFIG_UNICODE) && defined(CONFIG_FS_ENCRYPTION)

EXT4_ATTR_FEATURE(encrypted_casefold);

#endif

#ifdef CONFIG_TRANSPARENT_HUGEPAGE

EXT4_ATTR_FEATURE(blocksize_gt_pagesize);

#endif



static struct attribute *ext4_feat_attrs[] = {

	ATTR_LIST(lazy_itable_init),
@@ -351,6 +354,9 @@ static struct attribute *ext4_feat_attrs[] = { 
	ATTR_LIST(fast_commit),

#if IS_ENABLED(CONFIG_UNICODE) && defined(CONFIG_FS_ENCRYPTION)

	ATTR_LIST(encrypted_casefold),

#endif

#ifdef CONFIG_TRANSPARENT_HUGEPAGE

	ATTR_LIST(blocksize_gt_pagesize),

#endif

	NULL,

};