> +int dax_iomap_zero(loff_t pos, unsigned offset, unsigned size, > + struct iomap *iomap) > { > pgoff_t pgoff; > long rc, id; > + sector_t sector = iomap_sector(iomap, pos & PAGE_MASK); > > - rc = bdev_dax_pgoff(bdev, sector, PAGE_SIZE, &pgoff); > + rc = bdev_dax_pgoff(iomap->bdev, sector, PAGE_SIZE, &pgoff); > if (rc) > return rc; > > id = dax_read_lock(); > - rc = dax_zero_page_range(dax_dev, pgoff, offset, size); > + rc = dax_zero_page_range(iomap->dax_dev, pgoff, offset, size); > dax_read_unlock(id); > return rc; > } > -EXPORT_SYMBOL_GPL(__dax_zero_page_range); > +EXPORT_SYMBOL_GPL(dax_iomap_zero); This function is only used by fs/iomap/buffered-io.c, so no need to export it. > #ifdef CONFIG_FS_DAX > -int __dax_zero_page_range(struct block_device *bdev, > - struct dax_device *dax_dev, sector_t sector, > - unsigned int offset, unsigned int length); > +int dax_iomap_zero(loff_t pos, unsigned offset, unsigned size, > + struct iomap *iomap); > #else > -static inline int __dax_zero_page_range(struct block_device *bdev, > - struct dax_device *dax_dev, sector_t sector, > - unsigned int offset, unsigned int length) > +static inline int dax_iomap_zero(loff_t pos, unsigned offset, unsigned size, > + struct iomap *iomap) > { > return -ENXIO; > } Given that the only caller is under an IS_DAX() check you could just declare the function unconditionally and let the compiler optimize away the guaranteed dead call for the !CONFIG_FS_DAX case, like we do with various other functions.