Commit 868a8f1f authored by Robert Richter's avatar Robert Richter Committed by Dave Jiang
Browse files

cxl/region: Factor out code to find a root decoder's region 



In function cxl_add_to_region() there is code to determine a root
decoder's region. Factor that code out. This is in preparation to
further rework and simplify function cxl_add_to_region().

The reference count must be decremented after using the region.
cxl_find_region_by_range() is paired with the put_cxl_region cleanup
helper that can be used for this.

[dj: Fixed up "obj __free(...) = NULL" pattern]

Signed-off-by: default avatarRobert Richter <rrichter@amd.com>
Reviewed-by: default avatarGregory Price <gourry@gourry.net>
Reviewed-by: default avatarJonathan Cameron <Jonathan.Cameron@huawei.com>
Reviewed-by: default avatarDave Jiang <dave.jiang@intel.com>
Reviewed-by: default avatarDan Williams <dan.j.williams@intel.com>
Reviewed-by: default avatarAlison Schofield <alison.schofield@intel.com>
Reviewed-by: default avatar"Fabio M. De Francesco" <fabio.m.de.francesco@linux.intel.com>
Tested-by: default avatarGregory Price <gourry@gourry.net>
Acked-by: default avatarDan Williams <dan.j.williams@intel.com>
Link: https://patch.msgid.link/20250509150700.2817697-11-rrichter@amd.com


Signed-off-by: default avatarDave Jiang <dave.jiang@intel.com>
parent 9466ee98

drivers/cxl/core/region.c

+16 −10
Original line number Diff line number Diff line
@@ -3405,12 +3405,23 @@ static struct cxl_region *construct_region(struct cxl_root_decoder *cxlrd, 
	return cxlr;

}



static struct cxl_region *

cxl_find_region_by_range(struct cxl_root_decoder *cxlrd, struct range *hpa)

{

	struct device *region_dev;



	region_dev = device_find_child(&cxlrd->cxlsd.cxld.dev, hpa,

				       match_region_by_range);

	if (!region_dev)

		return NULL;



	return to_cxl_region(region_dev);

}



int cxl_add_to_region(struct cxl_endpoint_decoder *cxled)

{

	struct range *hpa = &cxled->cxld.hpa_range;

	struct device *region_dev;

	struct cxl_region_params *p;

	struct cxl_region *cxlr;

	bool attach = false;

	int rc;
@@ -3424,13 +3435,10 @@ int cxl_add_to_region(struct cxl_endpoint_decoder *cxled) 
	 * one does the construction and the others add to that.

	 */

	mutex_lock(&cxlrd->range_lock);

	region_dev = device_find_child(&cxlrd->cxlsd.cxld.dev, hpa,

				       match_region_by_range);

	if (!region_dev) {

	struct cxl_region *cxlr __free(put_cxl_region) =

		cxl_find_region_by_range(cxlrd, hpa);

	if (!cxlr)

		cxlr = construct_region(cxlrd, cxled);

		region_dev = &cxlr->dev;

	} else

		cxlr = to_cxl_region(region_dev);

	mutex_unlock(&cxlrd->range_lock);



	rc = PTR_ERR_OR_ZERO(cxlr);
@@ -3455,8 +3463,6 @@ int cxl_add_to_region(struct cxl_endpoint_decoder *cxled) 
				p->res);

	}



	put_device(region_dev);



	return rc;

}

EXPORT_SYMBOL_NS_GPL(cxl_add_to_region, "CXL");

drivers/cxl/cxl.h

+1 −0
Original line number Diff line number Diff line
@@ -741,6 +741,7 @@ struct cxl_root *find_cxl_root(struct cxl_port *port); 
DEFINE_FREE(put_cxl_root, struct cxl_root *, if (_T) put_device(&_T->port.dev))

DEFINE_FREE(put_cxl_port, struct cxl_port *, if (!IS_ERR_OR_NULL(_T)) put_device(&_T->dev))

DEFINE_FREE(put_cxl_root_decoder, struct cxl_root_decoder *, if (!IS_ERR_OR_NULL(_T)) put_device(&_T->cxlsd.cxld.dev))

DEFINE_FREE(put_cxl_region, struct cxl_region *, if (!IS_ERR_OR_NULL(_T)) put_device(&_T->dev))



int devm_cxl_enumerate_ports(struct cxl_memdev *cxlmd);

void cxl_bus_rescan(void);