--- e/fs/ext4/ext4.h	2022-08-19 19:46:26.317620400 +0800
+++ f/fs/ext4/ext4.h	2022-08-19 19:50:41.005830300 +0800
@@ -1081,6 +1081,7 @@ struct ext4_inode_info {
 	/* Protect concurrent accesses on i_fc_lblk_start, i_fc_lblk_len */
 	struct mutex i_fc_lock;
 
+	struct rw_semaphore i_bmap_sem;
 	/*
 	 * i_disksize keeps track of what the inode size is ON DISK, not
 	 * in memory.  During truncate, i_size is set to the new size by
--- e/fs/ext4/file.c	2022-08-19 19:45:25.253573600 +0800
+++ f/fs/ext4/file.c	2022-08-19 20:04:13.481483600 +0800
@@ -265,11 +265,13 @@ static ssize_t ext4_buffered_write_iter(
 	ret = ext4_write_checks(iocb, from);
 	if (ret <= 0)
 		goto out;
+	down_write(&EXT4_I(inode)->i_bmap_sem);
 
 	current->backing_dev_info = inode_to_bdi(inode);
 	ret = generic_perform_write(iocb, from);
 	current->backing_dev_info = NULL;
 
+	up_write(&EXT4_I(inode)->i_bmap_sem);
 out:
 	inode_unlock(inode);
 	if (likely(ret > 0)) {
--- e/fs/ext4/inode.c	2022-08-19 19:44:33.471445500 +0800
+++ f/fs/ext4/inode.c	2022-08-19 20:00:25.319110800 +0800
@@ -3154,7 +3154,7 @@ static sector_t ext4_bmap(struct address
 	sector_t ret = 0;
 	int err;
 
-	inode_lock_shared(inode);
+	down_read(&EXT4_I(inode)->i_bmap_sem);
 	/*
 	 * We can get here for an inline file via the FIBMAP ioctl
 	 */
@@ -3204,7 +3204,7 @@ static sector_t ext4_bmap(struct address
 	ret = iomap_bmap(mapping, block, &ext4_iomap_ops);
 
 out:
-	inode_unlock_shared(inode);
+	up_read(&EXT4_I(inode)->i_bmap_sem);
 	return ret;
 }
 
--- e/fs/ext4/super.c	2022-08-19 19:53:38.208033600 +0800
+++ f/fs/ext4/super.c	2022-08-19 19:55:01.503030300 +0800
@@ -1405,6 +1405,7 @@ static void init_once(void *foo)
 	INIT_LIST_HEAD(&ei->i_orphan);
 	init_rwsem(&ei->xattr_sem);
 	init_rwsem(&ei->i_data_sem);
+	init_rwsem(&ei->i_bmap_sem);
 	inode_init_once(&ei->vfs_inode);
 	ext4_fc_init_inode(&ei->vfs_inode);
 }