Re: [PATCH V7 04/19] dax: Save the kva from memremap

Dave Jiang
2026-02-18T23:33:40Z

On 1/18/26 3:31 PM, John Groves wrote:
> From: John Groves <john@groves.net>
>
> Save the kva from memremap because we need it for iomap rw support.
>
> Prior to famfs, there were no iomap users of /dev/dax - so the virtual
> address from memremap was not needed.
>
> Signed-off-by: John Groves <john@groves.net>

Reviewed-by: Dave Jiang <dave.jiang@intel.com>

> ---
> drivers/dax/dax-private.h | 2 ++
> drivers/dax/fsdev.c | 1 +
> 2 files changed, 3 insertions(+)
>
> diff --git a/drivers/dax/dax-private.h b/drivers/dax/dax-private.h
> index 0867115aeef2..4ae4d829d3ee 100644
> --- a/drivers/dax/dax-private.h
> +++ b/drivers/dax/dax-private.h
> @@ -69,6 +69,7 @@ struct dev_dax_range {
> * data while the device is activated in the driver.
> * @region - parent region
> * @dax_dev - core dax functionality
> + * @virt_addr: kva from memremap; used by fsdev_dax
> * @target_node: effective numa node if dev_dax memory range is onlined
> * @dyn_id: is this a dynamic or statically created instance
> * @id: ida allocated id when the dax_region is not static
> @@ -81,6 +82,7 @@ struct dev_dax_range {
> struct dev_dax {
> struct dax_region *region;
> struct dax_device *dax_dev;
> + void *virt_addr;
> unsigned int align;
> int target_node;
> bool dyn_id;
> diff --git a/drivers/dax/fsdev.c b/drivers/dax/fsdev.c
> index 29b7345f65b1..72f78f606e06 100644
> --- a/drivers/dax/fsdev.c
> +++ b/drivers/dax/fsdev.c
> @@ -201,6 +201,7 @@ static int fsdev_dax_probe(struct dev_dax *dev_dax)
> pr_debug("%s: offset detected phys=%llx pgmap_phys=%llx offset=%llx\n",
> __func__, phys, pgmap_phys, data_offset);
> }
> + dev_dax->virt_addr = addr + data_offset;
>
> inode = dax_inode(dax_dev);
> cdev = inode->i_cdev;