On Mon, Dec 18, 2023 at 04:07:39PM -0800, Bart Van Assche wrote: > Write hints applied with F_SET_RW_HINT on a block device affect the > shmem inode only. Propagate these hints to the block device inode > because that is the inode used when writing back dirty pages. What shmem inode? > @@ -317,6 +318,9 @@ static long fcntl_set_rw_hint(struct file *file, unsigned int cmd, > > inode_lock(inode); > inode->i_write_hint = hint; > + apply_whint = inode->i_fop->apply_whint; > + if (apply_whint) > + apply_whint(file, hint); Setting the hint in file->f_mapping->inode is the right thing here, not adding a method.