On Thu 22-02-18 23:17:51, Dan Williams wrote: > An address_space will only have dax exceptional entries when FS_DAX is > enabled. The current reliance on S_DAX causes compile failures when > S_DAX is defined for DEV_DAX, but FS_DAX is disabled. Make dax_mapping() > always return false so that mm/truncate.c drops its link time > dependencies on fs/dax.c. > > Cc: Alexander Viro <viro@xxxxxxxxxxxxxxxxxx> > Cc: linux-fsdevel@xxxxxxxxxxxxxxx > Cc: Christoph Hellwig <hch@xxxxxx> > Cc: Jan Kara <jack@xxxxxxx> > Cc: <stable@xxxxxxxxxxxxxxx> > Reported-by: kbuild test robot <fengguang.wu@xxxxxxxxx> > Fixes: dee410792419 ("/dev/dax, core: file operations and dax-mmap") > Signed-off-by: Dan Williams <dan.j.williams@xxxxxxxxx> Looks good. You can add: Reviewed-by: Jan Kara <jack@xxxxxxx> Honza > --- > include/linux/dax.h | 9 ++++++--- > 1 file changed, 6 insertions(+), 3 deletions(-) > > diff --git a/include/linux/dax.h b/include/linux/dax.h > index 0185ecdae135..62e8cf7eb566 100644 > --- a/include/linux/dax.h > +++ b/include/linux/dax.h > @@ -107,6 +107,10 @@ int dax_invalidate_mapping_entry_sync(struct address_space *mapping, > 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 bool dax_mapping(struct address_space *mapping) > +{ > + return mapping->host && IS_DAX(mapping->host); > +} > #else > static inline int __dax_zero_page_range(struct block_device *bdev, > struct dax_device *dax_dev, sector_t sector, > @@ -114,12 +118,11 @@ static inline int __dax_zero_page_range(struct block_device *bdev, > { > return -ENXIO; > } > -#endif > - > static inline bool dax_mapping(struct address_space *mapping) > { > - return mapping->host && IS_DAX(mapping->host); > + return false; > } > +#endif > > struct writeback_control; > int dax_writeback_mapping_range(struct address_space *mapping, > -- Jan Kara <jack@xxxxxxxx> SUSE Labs, CR