Commit 7f569e91 authored by Li Ming's avatar Li Ming Committed by Dave Jiang
Browse files

cxl/port: Use scoped_guard()/guard() to drop device_lock() for cxl_port 



A device_lock() and device_unlock() pair can be replaced by a cleanup
helper scoped_guard() or guard(), that can enhance code readability. In
CXL subsystem, still use device_lock() and device_unlock() pairs for cxl
port resource protection, most of them can be replaced by a
scoped_guard() or a guard() simply.

Suggested-by: default avatarDan Williams <dan.j.williams@intel.com>
Signed-off-by: default avatarLi Ming <ming4.li@intel.com>
Reviewed-by: default avatarJonathan Cameron <Jonathan.Cameron@huawei.com>
Link: https://patch.msgid.link/20240830013138.2256244-2-ming4.li@intel.com


Signed-off-by: default avatarDave Jiang <dave.jiang@intel.com>
parent dd2617eb

drivers/cxl/core/mbox.c

+1 −2
Original line number Diff line number Diff line
@@ -1214,7 +1214,7 @@ int cxl_mem_sanitize(struct cxl_memdev *cxlmd, u16 cmd) 
	int rc;



	/* synchronize with cxl_mem_probe() and decoder write operations */

	device_lock(&cxlmd->dev);

	guard(device)(&cxlmd->dev);

	endpoint = cxlmd->endpoint;

	down_read(&cxl_region_rwsem);

	/*
@@ -1226,7 +1226,6 @@ int cxl_mem_sanitize(struct cxl_memdev *cxlmd, u16 cmd) 
	else

		rc = -EBUSY;

	up_read(&cxl_region_rwsem);

	device_unlock(&cxlmd->dev);



	return rc;

}

drivers/cxl/core/port.c

+41 −52
Original line number Diff line number Diff line
@@ -1258,18 +1258,13 @@ EXPORT_SYMBOL_NS_GPL(devm_cxl_add_rch_dport, CXL); 
static int add_ep(struct cxl_ep *new)

{

	struct cxl_port *port = new->dport->port;

	int rc;



	device_lock(&port->dev);

	if (port->dead) {

		device_unlock(&port->dev);

	guard(device)(&port->dev);

	if (port->dead)

		return -ENXIO;

	}

	rc = xa_insert(&port->endpoints, (unsigned long)new->ep, new,

		       GFP_KERNEL);

	device_unlock(&port->dev);



	return rc;

	return xa_insert(&port->endpoints, (unsigned long)new->ep,

			 new, GFP_KERNEL);

}



/**
@@ -1393,14 +1388,14 @@ static void delete_endpoint(void *data) 
	struct cxl_port *endpoint = cxlmd->endpoint;

	struct device *host = endpoint_host(endpoint);



	device_lock(host);

	scoped_guard(device, host) {

		if (host->driver && !endpoint->dead) {

			devm_release_action(host, cxl_unlink_parent_dport, endpoint);

			devm_release_action(host, cxl_unlink_uport, endpoint);

			devm_release_action(host, unregister_port, endpoint);

		}

		cxlmd->endpoint = NULL;

	device_unlock(host);

	}

	put_device(&endpoint->dev);

	put_device(host);

}
@@ -1565,13 +1560,12 @@ static int add_port_attach_ep(struct cxl_memdev *cxlmd, 
	 * dereferencing the device of the port before the parent_port releasing.

	 */

	struct cxl_port *port __free(put_cxl_port) = NULL;

	device_lock(&parent_port->dev);

	scoped_guard(device, &parent_port->dev) {

		if (!parent_port->dev.driver) {

			dev_warn(&cxlmd->dev,

				 "port %s:%s disabled, failed to enumerate CXL.mem\n",

				 dev_name(&parent_port->dev), dev_name(uport_dev));

		port = ERR_PTR(-ENXIO);

		goto out;

			return -ENXIO;

		}



		port = find_cxl_port_at(parent_port, dport_dev, &dport);
@@ -1579,16 +1573,16 @@ static int add_port_attach_ep(struct cxl_memdev *cxlmd, 
			component_reg_phys = find_component_registers(uport_dev);

			port = devm_cxl_add_port(&parent_port->dev, uport_dev,

						 component_reg_phys, parent_dport);

			if (IS_ERR(port))

				return PTR_ERR(port);



			/* retry find to pick up the new dport information */

		if (!IS_ERR(port))

			port = find_cxl_port_at(parent_port, dport_dev, &dport);

			if (!port)

				return -ENXIO;

		}

	}

out:

	device_unlock(&parent_port->dev);



	if (IS_ERR(port))

		rc = PTR_ERR(port);

	else {

	dev_dbg(&cxlmd->dev, "add to new port %s:%s\n",

		dev_name(&port->dev), dev_name(port->uport_dev));

	rc = cxl_add_ep(dport, &cxlmd->dev);
@@ -1599,7 +1593,6 @@ static int add_port_attach_ep(struct cxl_memdev *cxlmd, 
		 */

		rc = -ENXIO;

	}

	}



	return rc;

}
@@ -1979,7 +1972,6 @@ EXPORT_SYMBOL_NS_GPL(cxl_decoder_add_locked, CXL); 
int cxl_decoder_add(struct cxl_decoder *cxld, int *target_map)

{

	struct cxl_port *port;

	int rc;



	if (WARN_ON_ONCE(!cxld))

		return -EINVAL;
@@ -1989,11 +1981,8 @@ int cxl_decoder_add(struct cxl_decoder *cxld, int *target_map) 


	port = to_cxl_port(cxld->dev.parent);



	device_lock(&port->dev);

	rc = cxl_decoder_add_locked(cxld, target_map);

	device_unlock(&port->dev);



	return rc;

	guard(device)(&port->dev);

	return cxl_decoder_add_locked(cxld, target_map);

}

EXPORT_SYMBOL_NS_GPL(cxl_decoder_add, CXL);

drivers/cxl/core/region.c

+13 −12
Original line number Diff line number Diff line
@@ -3094,11 +3094,11 @@ static void cxlr_release_nvdimm(void *_cxlr) 
	struct cxl_region *cxlr = _cxlr;

	struct cxl_nvdimm_bridge *cxl_nvb = cxlr->cxl_nvb;



	device_lock(&cxl_nvb->dev);

	scoped_guard(device, &cxl_nvb->dev) {

		if (cxlr->cxlr_pmem)

			devm_release_action(&cxl_nvb->dev, cxlr_pmem_unregister,

					    cxlr->cxlr_pmem);

	device_unlock(&cxl_nvb->dev);

	}

	cxlr->cxl_nvb = NULL;

	put_device(&cxl_nvb->dev);

}
@@ -3134,13 +3134,14 @@ static int devm_cxl_add_pmem_region(struct cxl_region *cxlr) 
	dev_dbg(&cxlr->dev, "%s: register %s\n", dev_name(dev->parent),

		dev_name(dev));



	device_lock(&cxl_nvb->dev);

	scoped_guard(device, &cxl_nvb->dev) {

		if (cxl_nvb->dev.driver)

			rc = devm_add_action_or_reset(&cxl_nvb->dev,

					      cxlr_pmem_unregister, cxlr_pmem);

						      cxlr_pmem_unregister,

						      cxlr_pmem);

		else

			rc = -ENXIO;

	device_unlock(&cxl_nvb->dev);

	}



	if (rc)

		goto err_bridge;

drivers/cxl/mem.c

+10 −12
Original line number Diff line number Diff line
@@ -168,19 +168,17 @@ static int cxl_mem_probe(struct device *dev) 


	cxl_setup_parent_dport(dev, dport);



	device_lock(endpoint_parent);

	scoped_guard(device, endpoint_parent) {

		if (!endpoint_parent->driver) {

			dev_err(dev, "CXL port topology %s not enabled\n",

				dev_name(endpoint_parent));

		rc = -ENXIO;

		goto unlock;

			return -ENXIO;

		}



		rc = devm_cxl_add_endpoint(endpoint_parent, cxlmd, dport);

unlock:

	device_unlock(endpoint_parent);

		if (rc)

			return rc;

	}



	/*

	 * The kernel may be operating out of CXL memory on this device,

drivers/cxl/pmem.c

+7 −9
Original line number Diff line number Diff line
@@ -233,15 +233,13 @@ static int detach_nvdimm(struct device *dev, void *data) 
	if (!is_cxl_nvdimm(dev))

		return 0;



	device_lock(dev);

	if (!dev->driver)

		goto out;



	scoped_guard(device, dev) {

		if (dev->driver) {

			cxl_nvd = to_cxl_nvdimm(dev);

			if (cxl_nvd->cxlmd && cxl_nvd->cxlmd->cxl_nvb == data)

				release = true;

out:

	device_unlock(dev);

		}

	}

	if (release)

		device_release_driver(dev);

	return 0;