Re: [PATCH] nvdimm/pmem: Set dax flag for all 'PFN_MAP' cases

[Alison Schofield]

On Wed, Jul 31, 2024 at 08:25:30PM +0800, Zhihao Cheng wrote:
> The dax is only supportted on pfn type pmem devices since commit
> f467fee48da4 ("block: move the dax flag to queue_limits"), fix it
> by adding dax flag setting for the missed case.

s/supportted/supported

How about adding failure messages like this:

Trying to mount DAX filesystem fails with this error:
mount: : wrong fs type, bad option, bad superblock on /dev/pmem7, missing codepage or helper program, or other error.
       dmesg(1) may have more information after failed mount system call.

dmesg: EXT4-fs (pmem7): DAX unsupported by block device.


Tested-by: Alison Schofield <alison.schofield@xxxxxxxxx>

> 
> Fixes: f467fee48da4 ("block: move the dax flag to queue_limits")
> Signed-off-by: Zhihao Cheng <chengzhihao1@xxxxxxxxxx>
> ---
>  drivers/nvdimm/pmem.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/drivers/nvdimm/pmem.c b/drivers/nvdimm/pmem.c
> index 1ae8b2351654..210fb77f51ba 100644
> --- a/drivers/nvdimm/pmem.c
> +++ b/drivers/nvdimm/pmem.c
> @@ -498,7 +498,7 @@ static int pmem_attach_disk(struct device *dev,
>  	}
>  	if (fua)
>  		lim.features |= BLK_FEAT_FUA;
> -	if (is_nd_pfn(dev))
> +	if (is_nd_pfn(dev) || pmem_should_map_pages(dev))
>  		lim.features |= BLK_FEAT_DAX;
>  
>  	if (!devm_request_mem_region(dev, res->start, resource_size(res),
> -- 
> 2.39.2
>