diff mbox series

[v3,3/4] cxl: Refactor usages of cxl_root from being referenced indirectly

Message ID 170440925509.3570725.9669871754496155658.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 p.m. UTC 
Commit 790815902ec6 ("cxl: Add support for _DSM Function for retrieving QTG ID")
introduced 'struct cxl_root', however all usages have been worked
indirectly through cxl_port. Refactor code such as find_cxl_root()
function to use 'struct cxl_root' directly.

Suggested-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: Dave Jiang <dave.jiang@intel.com>
---
 drivers/cxl/acpi.c      |    3 ++-
 drivers/cxl/core/cdat.c |   19 ++++++++++---------
 drivers/cxl/core/pmem.c |    6 ++++--
 drivers/cxl/core/port.c |    4 ++--
 drivers/cxl/cxl.h       |   14 +++++++-------
 drivers/cxl/port.c      |   12 ++++++++----
 6 files changed, 33 insertions(+), 25 deletions(-)

Comments

Dan Williams Jan. 4, 2024, 11:40 p.m. UTC | #1 
Dave Jiang wrote:
> Commit 790815902ec6 ("cxl: Add support for _DSM Function for retrieving QTG ID")
> introduced 'struct cxl_root', however all usages have been worked
> indirectly through cxl_port. Refactor code such as find_cxl_root()
> function to use 'struct cxl_root' directly.
> 
> Suggested-by: Dan Williams <dan.j.williams@intel.com>
> Signed-off-by: Dave Jiang <dave.jiang@intel.com>
> ---
>  drivers/cxl/acpi.c      |    3 ++-
>  drivers/cxl/core/cdat.c |   19 ++++++++++---------
>  drivers/cxl/core/pmem.c |    6 ++++--
>  drivers/cxl/core/port.c |    4 ++--
>  drivers/cxl/cxl.h       |   14 +++++++-------
>  drivers/cxl/port.c      |   12 ++++++++----
>  6 files changed, 33 insertions(+), 25 deletions(-)
> 
> diff --git a/drivers/cxl/acpi.c b/drivers/cxl/acpi.c
> index afc712264d1c..37cfd5516024 100644
> --- a/drivers/cxl/acpi.c
> +++ b/drivers/cxl/acpi.c
> @@ -295,10 +295,11 @@ cxl_acpi_evaluate_qtg_dsm(acpi_handle handle, struct access_coordinate *coord,
>  	return rc;
>  }
>  
> -static int cxl_acpi_qos_class(struct cxl_port *root_port,
> +static int cxl_acpi_qos_class(struct cxl_root *cxl_root,
>  			      struct access_coordinate *coord, int entries,
>  			      int *qos_class)
>  {
> +	struct cxl_port *root_port = &cxl_root->port;
>  	acpi_handle handle;
>  	struct device *dev;
>  
> diff --git a/drivers/cxl/core/cdat.c b/drivers/cxl/core/cdat.c
> index c5031e90bb96..280ca1508f21 100644
> --- a/drivers/cxl/core/cdat.c
> +++ b/drivers/cxl/core/cdat.c
> @@ -162,7 +162,6 @@ static int cxl_port_perf_data_calculate(struct cxl_port *port,
>  					struct xarray *dsmas_xa)
>  {
>  	struct access_coordinate c;
> -	struct cxl_root *cxl_root;
>  	struct dsmas_entry *dent;
>  	int valid_entries = 0;
>  	unsigned long index;
> @@ -174,12 +173,10 @@ static int cxl_port_perf_data_calculate(struct cxl_port *port,
>  		return rc;
>  	}
>  
> -	struct cxl_port *root_port __free(put_device) = find_cxl_root(port);
> -
> -	if (!root_port)
> +	struct cxl_root *cxl_root __free(put_device) = find_cxl_root(port);
> +	if (!cxl_root)
>  		return -ENODEV;
>  
> -	cxl_root = to_cxl_root(root_port);
>  	if (!cxl_root->ops || !cxl_root->ops->qos_class)
>  		return -EOPNOTSUPP;
>  
> @@ -196,7 +193,7 @@ static int cxl_port_perf_data_calculate(struct cxl_port *port,
>  						    dent->coord.write_bandwidth);
>  
>  		dent->entries = 1;
> -		rc = cxl_root->ops->qos_class(root_port, &dent->coord, 1, &qos_class);
> +		rc = cxl_root->ops->qos_class(cxl_root, &dent->coord, 1, &qos_class);
>  		if (rc != 1)
>  			continue;
>  
> @@ -352,15 +349,19 @@ static int cxl_qos_class_verify(struct cxl_memdev *cxlmd)
>  {
>  	struct cxl_dev_state *cxlds = cxlmd->cxlds;
>  	struct cxl_memdev_state *mds = to_cxl_memdev_state(cxlds);
> -	struct cxl_port *root_port __free(put_device) = NULL;
>  	LIST_HEAD(__discard);
>  	struct list_head *discard __free(dpa_perf) = &__discard;
> +	struct cxl_port *root_port;
>  	int rc;
>  
> -	root_port = find_cxl_root(cxlmd->endpoint);
> -	if (!root_port)
> +	struct cxl_root *cxl_root __free(put_device) =
> +		find_cxl_root(cxlmd->endpoint);
> +
> +	if (!cxl_root)
>  		return -ENODEV;
>  
> +	root_port = &cxl_root->port;
> +
>  	/* Check that the QTG IDs are all sane between end device and root decoders */
>  	cxl_qos_match(root_port, &mds->ram_perf_list, discard);
>  	cxl_qos_match(root_port, &mds->pmem_perf_list, discard);
> diff --git a/drivers/cxl/core/pmem.c b/drivers/cxl/core/pmem.c
> index fc94f5240327..da92a901b9e8 100644
> --- a/drivers/cxl/core/pmem.c
> +++ b/drivers/cxl/core/pmem.c
> @@ -64,12 +64,14 @@ static int match_nvdimm_bridge(struct device *dev, void *data)
>  
>  struct cxl_nvdimm_bridge *cxl_find_nvdimm_bridge(struct cxl_memdev *cxlmd)
>  {
> -	struct cxl_port *port = find_cxl_root(cxlmd->endpoint);
> +	struct cxl_root *cxl_root = find_cxl_root(cxlmd->endpoint);
> +	struct cxl_port *port;
>  	struct device *dev;
>  
> -	if (!port)
> +	if (!cxl_root)
>  		return NULL;
>  
> +	port = &cxl_root->port;
>  	dev = device_find_child(&port->dev, NULL, match_nvdimm_bridge);
>  	put_device(&port->dev);
>  
> diff --git a/drivers/cxl/core/port.c b/drivers/cxl/core/port.c
> index 8c00fd6be730..b8af09464363 100644
> --- a/drivers/cxl/core/port.c
> +++ b/drivers/cxl/core/port.c
> @@ -972,7 +972,7 @@ static bool dev_is_cxl_root_child(struct device *dev)
>  	return false;
>  }
>  
> -struct cxl_port *find_cxl_root(struct cxl_port *port)
> +struct cxl_root *find_cxl_root(struct cxl_port *port)
>  {
>  	struct cxl_port *iter = port;
>  
> @@ -982,7 +982,7 @@ struct cxl_port *find_cxl_root(struct cxl_port *port)
>  	if (!iter)
>  		return NULL;
>  	get_device(&iter->dev);
> -	return iter;
> +	return to_cxl_root(iter);
>  }
>  EXPORT_SYMBOL_NS_GPL(find_cxl_root, CXL);
>  
> diff --git a/drivers/cxl/cxl.h b/drivers/cxl/cxl.h
> index 492dbf63935f..8f43a06c4f72 100644
> --- a/drivers/cxl/cxl.h
> +++ b/drivers/cxl/cxl.h
> @@ -617,12 +617,6 @@ struct cxl_port {
>  	long pci_latency;
>  };
>  
> -struct cxl_root_ops {
> -	int (*qos_class)(struct cxl_port *root_port,
> -			 struct access_coordinate *coord, int entries,
> -			 int *qos_class);
> -};
> -
>  /**
>   * struct cxl_root - logical collection of root cxl_port items
>   *
> @@ -640,6 +634,12 @@ to_cxl_root(const struct cxl_port *port)
>  	return container_of(port, struct cxl_root, port);
>  }
>  
> +struct cxl_root_ops {
> +	int (*qos_class)(struct cxl_root *cxl_root,
> +			 struct access_coordinate *coord, int entries,
> +			 int *qos_class);
> +};
> +
>  static inline struct cxl_dport *
>  cxl_find_dport_by_dev(struct cxl_port *port, const struct device *dport_dev)
>  {
> @@ -734,7 +734,7 @@ struct cxl_port *devm_cxl_add_port(struct device *host,
>  				   struct cxl_dport *parent_dport);
>  struct cxl_root *devm_cxl_add_root(struct device *host,
>  				   const struct cxl_root_ops *ops);
> -struct cxl_port *find_cxl_root(struct cxl_port *port);
> +struct cxl_root *find_cxl_root(struct cxl_port *port);
>  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 da3c3a08bd62..656f2e03d2ea 100644
> --- a/drivers/cxl/port.c
> +++ b/drivers/cxl/port.c
> @@ -94,8 +94,8 @@ static int cxl_endpoint_port_probe(struct cxl_port *port)
>  	struct cxl_endpoint_dvsec_info info = { .port = port };
>  	struct cxl_memdev *cxlmd = to_cxl_memdev(port->uport_dev);
>  	struct cxl_dev_state *cxlds = cxlmd->cxlds;
> +	struct cxl_port *root_port;
>  	struct cxl_hdm *cxlhdm;
> -	struct cxl_port *root;
>  	int rc;
>  
>  	rc = cxl_dvsec_rr_decode(cxlds->dev, cxlds->cxl_dvsec, &info);
> @@ -130,14 +130,18 @@ 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()
>  	 */
> -	root = find_cxl_root(port);
> +	struct cxl_root *cxl_root __free(put_device) = find_cxl_root(port);
> +
> +	if (!cxl_root)
> +		return -ENODEV;

This is ignoring the comment above:

        /*
         * This can't fail in practice as CXL root exit unregisters all
         * descendant ports and that in turn synchronizes with cxl_port_probe()
         */
diff mbox series

Patch

diff --git a/drivers/cxl/acpi.c b/drivers/cxl/acpi.c
index afc712264d1c..37cfd5516024 100644
--- a/drivers/cxl/acpi.c
+++ b/drivers/cxl/acpi.c
@@ -295,10 +295,11 @@  cxl_acpi_evaluate_qtg_dsm(acpi_handle handle, struct access_coordinate *coord,
 	return rc;
 }
 
-static int cxl_acpi_qos_class(struct cxl_port *root_port,
+static int cxl_acpi_qos_class(struct cxl_root *cxl_root,
 			      struct access_coordinate *coord, int entries,
 			      int *qos_class)
 {
+	struct cxl_port *root_port = &cxl_root->port;
 	acpi_handle handle;
 	struct device *dev;
 
diff --git a/drivers/cxl/core/cdat.c b/drivers/cxl/core/cdat.c
index c5031e90bb96..280ca1508f21 100644
--- a/drivers/cxl/core/cdat.c
+++ b/drivers/cxl/core/cdat.c
@@ -162,7 +162,6 @@  static int cxl_port_perf_data_calculate(struct cxl_port *port,
 					struct xarray *dsmas_xa)
 {
 	struct access_coordinate c;
-	struct cxl_root *cxl_root;
 	struct dsmas_entry *dent;
 	int valid_entries = 0;
 	unsigned long index;
@@ -174,12 +173,10 @@  static int cxl_port_perf_data_calculate(struct cxl_port *port,
 		return rc;
 	}
 
-	struct cxl_port *root_port __free(put_device) = find_cxl_root(port);
-
-	if (!root_port)
+	struct cxl_root *cxl_root __free(put_device) = find_cxl_root(port);
+	if (!cxl_root)
 		return -ENODEV;
 
-	cxl_root = to_cxl_root(root_port);
 	if (!cxl_root->ops || !cxl_root->ops->qos_class)
 		return -EOPNOTSUPP;
 
@@ -196,7 +193,7 @@  static int cxl_port_perf_data_calculate(struct cxl_port *port,
 						    dent->coord.write_bandwidth);
 
 		dent->entries = 1;
-		rc = cxl_root->ops->qos_class(root_port, &dent->coord, 1, &qos_class);
+		rc = cxl_root->ops->qos_class(cxl_root, &dent->coord, 1, &qos_class);
 		if (rc != 1)
 			continue;
 
@@ -352,15 +349,19 @@  static int cxl_qos_class_verify(struct cxl_memdev *cxlmd)
 {
 	struct cxl_dev_state *cxlds = cxlmd->cxlds;
 	struct cxl_memdev_state *mds = to_cxl_memdev_state(cxlds);
-	struct cxl_port *root_port __free(put_device) = NULL;
 	LIST_HEAD(__discard);
 	struct list_head *discard __free(dpa_perf) = &__discard;
+	struct cxl_port *root_port;
 	int rc;
 
-	root_port = find_cxl_root(cxlmd->endpoint);
-	if (!root_port)
+	struct cxl_root *cxl_root __free(put_device) =
+		find_cxl_root(cxlmd->endpoint);
+
+	if (!cxl_root)
 		return -ENODEV;
 
+	root_port = &cxl_root->port;
+
 	/* Check that the QTG IDs are all sane between end device and root decoders */
 	cxl_qos_match(root_port, &mds->ram_perf_list, discard);
 	cxl_qos_match(root_port, &mds->pmem_perf_list, discard);
diff --git a/drivers/cxl/core/pmem.c b/drivers/cxl/core/pmem.c
index fc94f5240327..da92a901b9e8 100644
--- a/drivers/cxl/core/pmem.c
+++ b/drivers/cxl/core/pmem.c
@@ -64,12 +64,14 @@  static int match_nvdimm_bridge(struct device *dev, void *data)
 
 struct cxl_nvdimm_bridge *cxl_find_nvdimm_bridge(struct cxl_memdev *cxlmd)
 {
-	struct cxl_port *port = find_cxl_root(cxlmd->endpoint);
+	struct cxl_root *cxl_root = find_cxl_root(cxlmd->endpoint);
+	struct cxl_port *port;
 	struct device *dev;
 
-	if (!port)
+	if (!cxl_root)
 		return NULL;
 
+	port = &cxl_root->port;
 	dev = device_find_child(&port->dev, NULL, match_nvdimm_bridge);
 	put_device(&port->dev);
 
diff --git a/drivers/cxl/core/port.c b/drivers/cxl/core/port.c
index 8c00fd6be730..b8af09464363 100644
--- a/drivers/cxl/core/port.c
+++ b/drivers/cxl/core/port.c
@@ -972,7 +972,7 @@  static bool dev_is_cxl_root_child(struct device *dev)
 	return false;
 }
 
-struct cxl_port *find_cxl_root(struct cxl_port *port)
+struct cxl_root *find_cxl_root(struct cxl_port *port)
 {
 	struct cxl_port *iter = port;
 
@@ -982,7 +982,7 @@  struct cxl_port *find_cxl_root(struct cxl_port *port)
 	if (!iter)
 		return NULL;
 	get_device(&iter->dev);
-	return iter;
+	return to_cxl_root(iter);
 }
 EXPORT_SYMBOL_NS_GPL(find_cxl_root, CXL);
 
diff --git a/drivers/cxl/cxl.h b/drivers/cxl/cxl.h
index 492dbf63935f..8f43a06c4f72 100644
--- a/drivers/cxl/cxl.h
+++ b/drivers/cxl/cxl.h
@@ -617,12 +617,6 @@  struct cxl_port {
 	long pci_latency;
 };
 
-struct cxl_root_ops {
-	int (*qos_class)(struct cxl_port *root_port,
-			 struct access_coordinate *coord, int entries,
-			 int *qos_class);
-};
-
 /**
  * struct cxl_root - logical collection of root cxl_port items
  *
@@ -640,6 +634,12 @@  to_cxl_root(const struct cxl_port *port)
 	return container_of(port, struct cxl_root, port);
 }
 
+struct cxl_root_ops {
+	int (*qos_class)(struct cxl_root *cxl_root,
+			 struct access_coordinate *coord, int entries,
+			 int *qos_class);
+};
+
 static inline struct cxl_dport *
 cxl_find_dport_by_dev(struct cxl_port *port, const struct device *dport_dev)
 {
@@ -734,7 +734,7 @@  struct cxl_port *devm_cxl_add_port(struct device *host,
 				   struct cxl_dport *parent_dport);
 struct cxl_root *devm_cxl_add_root(struct device *host,
 				   const struct cxl_root_ops *ops);
-struct cxl_port *find_cxl_root(struct cxl_port *port);
+struct cxl_root *find_cxl_root(struct cxl_port *port);
 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 da3c3a08bd62..656f2e03d2ea 100644
--- a/drivers/cxl/port.c
+++ b/drivers/cxl/port.c
@@ -94,8 +94,8 @@  static int cxl_endpoint_port_probe(struct cxl_port *port)
 	struct cxl_endpoint_dvsec_info info = { .port = port };
 	struct cxl_memdev *cxlmd = to_cxl_memdev(port->uport_dev);
 	struct cxl_dev_state *cxlds = cxlmd->cxlds;
+	struct cxl_port *root_port;
 	struct cxl_hdm *cxlhdm;
-	struct cxl_port *root;
 	int rc;
 
 	rc = cxl_dvsec_rr_decode(cxlds->dev, cxlds->cxl_dvsec, &info);
@@ -130,14 +130,18 @@  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()
 	 */
-	root = find_cxl_root(port);
+	struct cxl_root *cxl_root __free(put_device) = find_cxl_root(port);
+
+	if (!cxl_root)
+		return -ENODEV;
+
+	root_port = &cxl_root->port;
 
 	/*
 	 * Now that all endpoint decoders are successfully enumerated, try to
 	 * assemble regions from committed decoders
 	 */
-	device_for_each_child(&port->dev, root, discover_region);
-	put_device(&root->dev);
+	device_for_each_child(&root_port->dev, root_port, discover_region);
 
 	return 0;
 }