On 26/03/25 02:28PM, Dave Jiang wrote: > > > On 3/23/26 5:39 PM, John Groves wrote: > > From: John Groves <[email protected]> > > > > fsdev: Add dax_operations for use by famfs. > > > > This replicates the functionality from drivers/nvdimm/pmem.c that > > conventional fs-dax file systems (e.g. xfs) use to support dax > > read/write/mmap to a daxdev - without which famfs can't sit atop a > > daxdev. > > > > - These methods are based on pmem_dax_ops from drivers/nvdimm/pmem.c > > - fsdev_dax_direct_access() returns the hpa, pfn and kva. The kva was > > newly stored as dev_dax->virt_addr by dev_dax_probe(). > > - The hpa/pfn are used for mmap (dax_iomap_fault()), and the kva is used > > for read/write (dax_iomap_rw()) > > - fsdev_dax_recovery_write() and dev_dax_zero_page_range() have not been > > tested yet. I'm looking for suggestions as to how to test those. > > - dax-private.h: add dev_dax->cached_size, which fsdev needs to > > remember. The dev_dax size cannot change while a driver is bound > > (dev_dax_resize returns -EBUSY if dev->driver is set). Caching the size > > at probe time allows fsdev's direct_access path can use it without > > acquiring dax_dev_rwsem (which isn't exported anyway). > > > > Signed-off-by: John Groves <[email protected]> > > --- > > drivers/dax/dax-private.h | 1 + > > drivers/dax/fsdev.c | 84 +++++++++++++++++++++++++++++++++++++++ > > 2 files changed, 85 insertions(+) > > > > diff --git a/drivers/dax/dax-private.h b/drivers/dax/dax-private.h > > index 7a3727d76a68..ee8f3af8387f 100644 > > --- a/drivers/dax/dax-private.h > > +++ b/drivers/dax/dax-private.h > > @@ -85,6 +85,7 @@ struct dev_dax { > > struct dax_region *region; > > struct dax_device *dax_dev; > > void *virt_addr; > > + u64 cached_size; > > Just caught this. Need a kdoc entry. > > DJ
Thank you! Added for v10 John
