Re: [PATCH v4 20/28] cxl/core: Return endpoint decoder information from region search

[Fan Ni <nifan.cxl@gmail.com>]

On Mon, Oct 07, 2024 at 06:16:26PM -0500, Ira Weiny wrote:
> cxl_dpa_to_region() finds the region from a <DPA, device> tuple.
> The search involves finding the device endpoint decoder as well.
> 
> Dynamic capacity extent processing uses the endpoint decoder HPA
> information to calculate the HPA offset.  In addition, well behaved
> extents should be contained within an endpoint decoder.
> 
> Return the endpoint decoder found to be used in subsequent DCD code.
> 
> Signed-off-by: Ira Weiny <ira.weiny@intel.com>

Reviewed-by: Fan Ni <fan.ni@samsung.com>

> ---
>  drivers/cxl/core/core.h   | 6 ++++--
>  drivers/cxl/core/mbox.c   | 2 +-
>  drivers/cxl/core/memdev.c | 4 ++--
>  drivers/cxl/core/region.c | 8 +++++++-
>  4 files changed, 14 insertions(+), 6 deletions(-)
> 
> diff --git a/drivers/cxl/core/core.h b/drivers/cxl/core/core.h
> index 5d6fe7ab0a78..94ee06cfbdca 100644
> --- a/drivers/cxl/core/core.h
> +++ b/drivers/cxl/core/core.h
> @@ -39,7 +39,8 @@ void cxl_decoder_kill_region(struct cxl_endpoint_decoder *cxled);
>  int cxl_region_init(void);
>  void cxl_region_exit(void);
>  int cxl_get_poison_by_endpoint(struct cxl_port *port);
> -struct cxl_region *cxl_dpa_to_region(const struct cxl_memdev *cxlmd, u64 dpa);
> +struct cxl_region *cxl_dpa_to_region(const struct cxl_memdev *cxlmd, u64 dpa,
> +				     struct cxl_endpoint_decoder **cxled);
>  u64 cxl_dpa_to_hpa(struct cxl_region *cxlr, const struct cxl_memdev *cxlmd,
>  		   u64 dpa);
>  
> @@ -50,7 +51,8 @@ static inline u64 cxl_dpa_to_hpa(struct cxl_region *cxlr,
>  	return ULLONG_MAX;
>  }
>  static inline
> -struct cxl_region *cxl_dpa_to_region(const struct cxl_memdev *cxlmd, u64 dpa)
> +struct cxl_region *cxl_dpa_to_region(const struct cxl_memdev *cxlmd, u64 dpa,
> +				     struct cxl_endpoint_decoder **cxled)
>  {
>  	return NULL;
>  }
> diff --git a/drivers/cxl/core/mbox.c b/drivers/cxl/core/mbox.c
> index 3ba465823564..584d7d282a97 100644
> --- a/drivers/cxl/core/mbox.c
> +++ b/drivers/cxl/core/mbox.c
> @@ -916,7 +916,7 @@ void cxl_event_trace_record(const struct cxl_memdev *cxlmd,
>  		guard(rwsem_read)(&cxl_dpa_rwsem);
>  
>  		dpa = le64_to_cpu(evt->media_hdr.phys_addr) & CXL_DPA_MASK;
> -		cxlr = cxl_dpa_to_region(cxlmd, dpa);
> +		cxlr = cxl_dpa_to_region(cxlmd, dpa, NULL);
>  		if (cxlr)
>  			hpa = cxl_dpa_to_hpa(cxlr, cxlmd, dpa);
>  
> diff --git a/drivers/cxl/core/memdev.c b/drivers/cxl/core/memdev.c
> index 2565b10a769c..31872c03006b 100644
> --- a/drivers/cxl/core/memdev.c
> +++ b/drivers/cxl/core/memdev.c
> @@ -313,7 +313,7 @@ int cxl_inject_poison(struct cxl_memdev *cxlmd, u64 dpa)
>  	if (rc)
>  		goto out;
>  
> -	cxlr = cxl_dpa_to_region(cxlmd, dpa);
> +	cxlr = cxl_dpa_to_region(cxlmd, dpa, NULL);
>  	if (cxlr)
>  		dev_warn_once(cxl_mbox->host,
>  			      "poison inject dpa:%#llx region: %s\n", dpa,
> @@ -377,7 +377,7 @@ int cxl_clear_poison(struct cxl_memdev *cxlmd, u64 dpa)
>  	if (rc)
>  		goto out;
>  
> -	cxlr = cxl_dpa_to_region(cxlmd, dpa);
> +	cxlr = cxl_dpa_to_region(cxlmd, dpa, NULL);
>  	if (cxlr)
>  		dev_warn_once(cxl_mbox->host,
>  			      "poison clear dpa:%#llx region: %s\n", dpa,
> diff --git a/drivers/cxl/core/region.c b/drivers/cxl/core/region.c
> index 34a6f447e75b..a0c181cc33e4 100644
> --- a/drivers/cxl/core/region.c
> +++ b/drivers/cxl/core/region.c
> @@ -2827,6 +2827,7 @@ int cxl_get_poison_by_endpoint(struct cxl_port *port)
>  struct cxl_dpa_to_region_context {
>  	struct cxl_region *cxlr;
>  	u64 dpa;
> +	struct cxl_endpoint_decoder *cxled;
>  };
>  
>  static int __cxl_dpa_to_region(struct device *dev, void *arg)
> @@ -2860,11 +2861,13 @@ static int __cxl_dpa_to_region(struct device *dev, void *arg)
>  			dev_name(dev));
>  
>  	ctx->cxlr = cxlr;
> +	ctx->cxled = cxled;
>  
>  	return 1;
>  }
>  
> -struct cxl_region *cxl_dpa_to_region(const struct cxl_memdev *cxlmd, u64 dpa)
> +struct cxl_region *cxl_dpa_to_region(const struct cxl_memdev *cxlmd, u64 dpa,
> +				     struct cxl_endpoint_decoder **cxled)
>  {
>  	struct cxl_dpa_to_region_context ctx;
>  	struct cxl_port *port;
> @@ -2876,6 +2879,9 @@ struct cxl_region *cxl_dpa_to_region(const struct cxl_memdev *cxlmd, u64 dpa)
>  	if (port && is_cxl_endpoint(port) && cxl_num_decoders_committed(port))
>  		device_for_each_child(&port->dev, &ctx, __cxl_dpa_to_region);
>  
> +	if (cxled)
> +		*cxled = ctx.cxled;
> +
>  	return ctx.cxlr;
>  }
>  
> 
> -- 
> 2.46.0
> 

-- 
Fan Ni