On Tue, May 03, 2022 at 07:41:24AM -0700, Christoph Hellwig wrote: > The changes looks good: > > Reviewed-by: Christoph Hellwig <hch@xxxxxx> > > But I wonder if we shouldn't really just drop these nobh helpers > entirely. They were added to save lowmem on highmem systems with a lot > of highmem, but I really don't think we should continue optimizaing for > that. They certainly don't have a lot of users: $ git grep -w nobh_truncate_page fs/buffer.c:int nobh_truncate_page(struct address_space *mapping, fs/buffer.c:EXPORT_SYMBOL(nobh_truncate_page); fs/ext2/inode.c: error = nobh_truncate_page(inode->i_mapping, fs/jfs/inode.c: nobh_truncate_page(ip->i_mapping, ip->i_size, jfs_get_block); include/linux/buffer_head.h:int nobh_truncate_page(struct address_space *, loff_t, get_block_t *); So just two for this helper. The other nobh_ helpers are in a similar position (just ext2 and jfs). I had a quick look at converting jfs to iomap, and that seems quite reasonable. So ... once ext2 is converted to iomap, all the nobh helpers can go away as being unused?
