diff mbox series

[v3,4/4] cxl: Introduce put_cxl_root() helper function to have symmetry of find_cxl_root()

Message ID 170440926084.3570725.9962332024836108779.stgit@djiang5-mobl3
State New, archived
Headers show
Series [v3,1/4] cxl: Add check for NULL ptr after calling find_cxl_root() | expand

Commit Message

Dave Jiang Jan. 4, 2024, 11:01 p.m. UTC 
Add a helper function put_cxl_root() to maintain symmetry for
find_cxl_root() function instead of relying on open coding of the
put_device() in order to dereference the 'struct device' that happens via
get_device() in find_cxl_root(). Add cleanups for all code paths that
calls put_device() after find_cxl_root().

Suggested-by: Robert Richter <rrichter@amd.com>
Signed-off-by: Dave Jiang <dave.jiang@intel.com>
---
v3:
- Adjust for cxl_root as parameter for find_cxl_root()
- Add NULL ptr check fore __free(). (Dan)
- Fix DEFINE_FREE() macro to name it put_cxl_root (Dan)
- Cleanup all functions calling put_cxl_root() and related calls. (Dan)

v2:
- Make put_cxl_root() an exported function to be symmetric to
  find_cxl_root(). (Robert)
---
 drivers/cxl/core/cdat.c |    5 +++--
 drivers/cxl/core/pmem.c |    4 ++--
 drivers/cxl/core/port.c |    9 +++++++++
 drivers/cxl/cxl.h       |    3 +++
 drivers/cxl/port.c      |    2 +-
 5 files changed, 18 insertions(+), 5 deletions(-)
diff mbox series

Patch

diff --git a/drivers/cxl/core/cdat.c b/drivers/cxl/core/cdat.c
index 280ca1508f21..260cf2d621cd 100644
--- a/drivers/cxl/core/cdat.c
+++ b/drivers/cxl/core/cdat.c
@@ -173,7 +173,8 @@  static int cxl_port_perf_data_calculate(struct cxl_port *port,
 		return rc;
 	}
 
-	struct cxl_root *cxl_root __free(put_device) = find_cxl_root(port);
+	struct cxl_root *cxl_root __free(put_cxl_root) = find_cxl_root(port);
+
 	if (!cxl_root)
 		return -ENODEV;
 
@@ -354,7 +355,7 @@  static int cxl_qos_class_verify(struct cxl_memdev *cxlmd)
 	struct cxl_port *root_port;
 	int rc;
 
-	struct cxl_root *cxl_root __free(put_device) =
+	struct cxl_root *cxl_root __free(put_cxl_root) =
 		find_cxl_root(cxlmd->endpoint);
 
 	if (!cxl_root)
diff --git a/drivers/cxl/core/pmem.c b/drivers/cxl/core/pmem.c
index da92a901b9e8..df3d11257511 100644
--- a/drivers/cxl/core/pmem.c
+++ b/drivers/cxl/core/pmem.c
@@ -64,7 +64,8 @@  static int match_nvdimm_bridge(struct device *dev, void *data)
 
 struct cxl_nvdimm_bridge *cxl_find_nvdimm_bridge(struct cxl_memdev *cxlmd)
 {
-	struct cxl_root *cxl_root = find_cxl_root(cxlmd->endpoint);
+	struct cxl_root *cxl_root __free(put_cxl_root) =
+		find_cxl_root(cxlmd->endpoint);
 	struct cxl_port *port;
 	struct device *dev;
 
@@ -73,7 +74,6 @@  struct cxl_nvdimm_bridge *cxl_find_nvdimm_bridge(struct cxl_memdev *cxlmd)
 
 	port = &cxl_root->port;
 	dev = device_find_child(&port->dev, NULL, match_nvdimm_bridge);
-	put_device(&port->dev);
 
 	if (!dev)
 		return NULL;
diff --git a/drivers/cxl/core/port.c b/drivers/cxl/core/port.c
index b8af09464363..63a4e3c2baed 100644
--- a/drivers/cxl/core/port.c
+++ b/drivers/cxl/core/port.c
@@ -986,6 +986,15 @@  struct cxl_root *find_cxl_root(struct cxl_port *port)
 }
 EXPORT_SYMBOL_NS_GPL(find_cxl_root, CXL);
 
+void put_cxl_root(struct cxl_root *cxl_root)
+{
+	if (!cxl_root)
+		return;
+
+	put_device(&cxl_root->port.dev);
+}
+EXPORT_SYMBOL_NS_GPL(put_cxl_root, CXL);
+
 static struct cxl_dport *find_dport(struct cxl_port *port, int id)
 {
 	struct cxl_dport *dport;
diff --git a/drivers/cxl/cxl.h b/drivers/cxl/cxl.h
index 8f43a06c4f72..3a5004aab97a 100644
--- a/drivers/cxl/cxl.h
+++ b/drivers/cxl/cxl.h
@@ -735,6 +735,9 @@  struct cxl_port *devm_cxl_add_port(struct device *host,
 struct cxl_root *devm_cxl_add_root(struct device *host,
 				   const struct cxl_root_ops *ops);
 struct cxl_root *find_cxl_root(struct cxl_port *port);
+void put_cxl_root(struct cxl_root *cxl_root);
+DEFINE_FREE(put_cxl_root, struct cxl_root *, if (_T) put_cxl_root(_T))
+
 int devm_cxl_enumerate_ports(struct cxl_memdev *cxlmd);
 void cxl_bus_rescan(void);
 void cxl_bus_drain(void);
diff --git a/drivers/cxl/port.c b/drivers/cxl/port.c
index 656f2e03d2ea..27b7b45476e3 100644
--- a/drivers/cxl/port.c
+++ b/drivers/cxl/port.c
@@ -130,7 +130,7 @@  static int cxl_endpoint_port_probe(struct cxl_port *port)
 	 * This can't fail in practice as CXL root exit unregisters all
 	 * descendant ports and that in turn synchronizes with cxl_port_probe()
 	 */
-	struct cxl_root *cxl_root __free(put_device) = find_cxl_root(port);
+	struct cxl_root *cxl_root __free(put_cxl_root) = find_cxl_root(port);
 
 	if (!cxl_root)
 		return -ENODEV;