[PATCH 38/41] ext4: Track metadata bhs in fs-private inode part

Jan Kara
2026-03-20T13:43:43Z

Track metadata bhs for an inode in fs-private part of the inode. We need
the tracking only for nojournal mode so this is somewhat wasteful. We
can relatively easily make the mapping_metadata_bhs struct dynamically
allocated similarly to how we treat jbd2_inode but let's leave that for
ext4 specific series once the dust settles a bit.

Signed-off-by: Jan Kara <jack@suse.cz>
---
fs/ext4/ext4.h | 1 +
fs/ext4/ext4_jbd2.c | 3 ++-
fs/ext4/fsync.c | 5 +++--
fs/ext4/inode.c | 4 ++--
fs/ext4/super.c | 3 ++-
5 files changed, 10 insertions(+), 6 deletions(-)

diff --git a/fs/ext4/ext4.h b/fs/ext4/ext4.h
index 293f698b7042..8df3617fd0e7 100644
--- a/fs/ext4/ext4.h
+++ b/fs/ext4/ext4.h
@@ -1121,6 +1121,7 @@ struct ext4_inode_info {
struct rw_semaphore i_data_sem;
struct inode vfs_inode;
struct jbd2_inode *jinode;
+ struct mapping_metadata_bhs i_metadata_bhs;

/*
* File creation time. Its function is same as that of
diff --git a/fs/ext4/ext4_jbd2.c b/fs/ext4/ext4_jbd2.c
index 05e5946ed9b3..9a8c225f2753 100644
--- a/fs/ext4/ext4_jbd2.c
+++ b/fs/ext4/ext4_jbd2.c
@@ -390,7 +390,8 @@ int __ext4_handle_dirty_metadata(const char *where, unsigned int line,
}
} else {
if (inode)
- mark_buffer_dirty_inode(bh, inode);
+ mmb_mark_buffer_dirty(bh,
+ &EXT4_I(inode)->i_metadata_bhs);
else
mark_buffer_dirty(bh);
if (inode && inode_needs_sync(inode)) {
diff --git a/fs/ext4/fsync.c b/fs/ext4/fsync.c
index e476c6de3074..709c403273aa 100644
--- a/fs/ext4/fsync.c
+++ b/fs/ext4/fsync.c
@@ -68,7 +68,7 @@ static int ext4_sync_parent(struct inode *inode)
* through ext4_evict_inode()) and so we are safe to flush
* metadata blocks and the inode.
*/
- ret = sync_mapping_buffers(inode->i_mapping);
+ ret = mmb_sync_buffers(&EXT4_I(inode)->i_metadata_bhs);
if (ret)
break;
ret = sync_inode_metadata(inode, 1);
@@ -85,7 +85,8 @@ static int ext4_fsync_nojournal(struct file *file, loff_t start, loff_t end,
struct inode *inode = file->f_inode;
int ret;

- ret = generic_buffers_fsync_noflush(file, start, end, datasync);
+ ret = generic_mmb_fsync_noflush(file, &EXT4_I(inode)->i_metadata_bhs,
+ start, end, datasync);
if (!ret)
ret = ext4_sync_parent(inode);
if (test_opt(inode->i_sb, BARRIER))
diff --git a/fs/ext4/inode.c b/fs/ext4/inode.c
index 011cb2eb16a2..abc17ef0c9ee 100644
--- a/fs/ext4/inode.c
+++ b/fs/ext4/inode.c
@@ -187,7 +187,7 @@ void ext4_evict_inode(struct inode *inode)
truncate_inode_pages_final(&inode->i_data);
/* Avoid mballoc special inode which has no proper iops */
if (!EXT4_SB(inode->i_sb)->s_journal)
- sync_mapping_buffers(&inode->i_data);
+ mmb_sync_buffers(&EXT4_I(inode)->i_metadata_bhs);
goto no_delete;
}

@@ -3436,7 +3436,7 @@ static bool ext4_inode_datasync_dirty(struct inode *inode)
}

/* Any metadata buffers to write? */
- if (mmb_has_buffers(&inode->i_mapping->i_metadata_bhs))
+ if (mmb_has_buffers(&EXT4_I(inode)->i_metadata_bhs))
return true;
return inode_state_read_once(inode) & I_DIRTY_DATASYNC;
}
diff --git a/fs/ext4/super.c b/fs/ext4/super.c
index ea827b0ecc8d..1b2b4ad62a10 100644
--- a/fs/ext4/super.c
+++ b/fs/ext4/super.c
@@ -1428,6 +1428,7 @@ static struct inode *ext4_alloc_inode(struct super_block *sb)
INIT_WORK(&ei->i_rsv_conversion_work, ext4_end_io_rsv_work);
ext4_fc_init_inode(&ei->vfs_inode);
spin_lock_init(&ei->i_fc_lock);
+ mmb_init(&ei->i_metadata_bhs, &ei->vfs_inode.i_data);
return &ei->vfs_inode;
}

@@ -1525,7 +1526,7 @@ void ext4_clear_inode(struct inode *inode)
{
ext4_fc_del(inode);
if (!EXT4_SB(inode->i_sb)->s_journal)
- invalidate_inode_buffers(inode);
+ mmb_invalidate_buffers(&EXT4_I(inode)->i_metadata_bhs);
clear_inode(inode);
ext4_discard_preallocations(inode);
ext4_es_remove_extent(inode, 0, EXT_MAX_BLOCKS);
--
2.51.0