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X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?us-ascii?Q?5jt396vGTT5acz2VfUArZci3V73Xi1zU2mkl5ZP+pLqe++voApF3L0bgOIH7?= =?us-ascii?Q?7M59Ewey8Y4LZb808L94bMNe5pUl1ebHkrqcrJ/q+heU0hqQu94y5p5g3gWG?= =?us-ascii?Q?GmxX32AuBqxqh/n57no64z15UkvdfnobgV6Tr6wIAt1vHhR7DSbl3LaJYSHS?= =?us-ascii?Q?e8EKwgL6EEoj78PWSOz/HlaHpflrWh3DmAP3GXLgtdKh5ccsAiSohRc5x9r9?= =?us-ascii?Q?Mhk8C5GO3PCga8sJ1PYO0h5hVfm0mHUaVkLW1ti1R0WxSl/MOWqiING0FRk3?= =?us-ascii?Q?NVaZwjnGuNg/5oV92WYYAvj5NQHgOTVuPDHsiK/SLnlAoGlKm4bLXOURZsTQ?= =?us-ascii?Q?Homkdlt8W4yFeTNWQrA33AZ3xbO6bJqXW9mSf5b9033YmCAeV0sjO1KI9g6D?= =?us-ascii?Q?zMHHfn/8T/+vnD2MEFs4aTnSUCj7kjLAfGxFLd4X6mRl27GhG51q7BLvysUO?= =?us-ascii?Q?tmeRqA/03LOpMMC6S+vUhVQ1qfuI+kEI1FRwfqeNM/T8kkszg8hn4QHX8hs5?= =?us-ascii?Q?y46Vdgh4DJt2eoDnlguLKkS3Pk4cX8/Oznoa91dql/9TCRWaJwbEHgiKjCB9?= =?us-ascii?Q?8z/R0LEQCsAmWuk3MIlQtYtZBPXLkOhEifhdTnOKK4Byi/RWWYs2gRuJW1kn?= =?us-ascii?Q?skJROo8pjghUr26c6teNO9CKKqN1HMS6itygvYJ70XvhGpgEqgUKWBK1B4d/?= =?us-ascii?Q?sgZDMhsj2DQYcoGZ/jN76QvPxc2L4rigTWkmP555rd4vH7bGCsSPWhCfcw0W?= =?us-ascii?Q?ZX9P6AAkc8XU22Zt/qobJ81v6OeuczHoJW6AxHWJrJjfF++1IH/MnQ2h5ALw?= =?us-ascii?Q?gZ9rKzmkKgaOJXDfAnkOYw+/6VzQi/xbf4snDM7sZuqjI5yt+DBNmKy5Lcoe?= =?us-ascii?Q?3h+yGOK2bW30M82eGs2+YOfYVU6joGuSZb7d9/DGrZhQBEajK1hrVnlEHARn?= =?us-ascii?Q?IC/juKayTqRde1oMaodLVU/WPBK25AIDSsEgh8bj+PmMMvE6WOQbVwSDaf+v?= =?us-ascii?Q?vg9ibeq4NVPlcDCkPPvvTZ7juH5NBlkg3d5BAs5Gvz5eo+mOMuQ3mrIBAciI?= =?us-ascii?Q?JMwJ7bT+mvHKp8ftiMoChfd/LxFi3nRQMn8G/pNirv/gFBxmIFNTwbgqtreg?= =?us-ascii?Q?B+/KBZIgWi9IPKZvLzMJYd3JgS3i2jWEEABHn/Q4gXc6lb5RLdKaCzqvwOBa?= =?us-ascii?Q?5iR/6PxQIE8tRzhyM2WmvP0HzoLFx0Gc4vFMXMoQ71zDeYTd8rg3HqzOK875?= =?us-ascii?Q?RWf8fBJmkNZUzJfn4wKdgyi1e03PaLzDv1s5qhtmfNu0Hq3mdVSp4nm7BaQ/?= =?us-ascii?Q?dqRYNN3mmyTg+C3V3LI0K9PrPUOdw7eccK4+8GUIvipeXXYO9vF0yC0KNQhQ?= =?us-ascii?Q?0ojoRZ/EsF+swyPBghtOZdHFDNF9BIXRQlJ2iFSM64E7G/tJoX+Us4sUAOMD?= =?us-ascii?Q?0jTZwEPG/iPrx5qNIGxaS6D59QasO82Tol9DQtDD1sz+hCzBeId605fgTlGY?= =?us-ascii?Q?J556IxL9JPQPcsiuJyLfUe+gaqZvE4BGxUHcugs1sEgIfmArmuOzbjRgCUos?= =?us-ascii?Q?7ynuqxWbzVc5CUk8Q/Wr0Nmpz8mVthJ+12Zys93vn6ZlNXcZ13S6LWe6oggz?= =?us-ascii?Q?+1Ijn8szpx8IzI1vRlQeVoSdMQiM2Pw8ThkkC4711BU2NuKlOXCrwORLLbIG?= =?us-ascii?Q?iqk2bdvyt5piJ/XOltAh3z8PH+GTrGG5y6gMch065un0Q1krQTGjcxDIdkwV?= =?us-ascii?Q?pguTdXTfEg=3D=3D?= X-OriginatorOrg: Nvidia.com X-MS-Exchange-CrossTenant-Network-Message-Id: 5cac65eb-f1a7-4ecb-13aa-08df273d648a X-MS-Exchange-CrossTenant-AuthSource: LY0PR12MB727857.namprd12.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 11 Oct 2026 02:14:34.3934 (UTC) X-MS-Exchange-CrossTenant-FromEntityHeader: Hosted X-MS-Exchange-CrossTenant-Id: 43083d15-7273-40c1-b7db-39efd9ccc17a X-MS-Exchange-CrossTenant-MailboxType: HOSTED X-MS-Exchange-CrossTenant-UserPrincipalName: FRxeIse1TnZv8WSWIp0MSO3tt3JzCoJrv6A+P2o6FhicgauAeTqqileWFhFjsZoCW9RYpdZia+VgxrvetmEqwQ== X-MS-Exchange-Transport-CrossTenantHeadersStamped: MW4PR12MB6951 read_cdat_data() resolves a CXL port's upstream device to its backing PCI device. HDM cache updates need the same mapping. Factor the lookup into cxl_port_get_uport_pci_dev() and return a referenced PCI device to make caller ownership explicit. Use automatic reference cleanup in read_cdat_data(), as suggested by Li Ming, so early returns release the PCI device reference. Signed-off-by: Srirangan Madhavan Reviewed-by: Jonathan Cameron Reviewed-by: Dave Jiang Reviewed-by: Richard Cheng Reviewed-by: Li Ming --- drivers/cxl/core/core.h | 1 + drivers/cxl/core/pci.c | 16 ++-------------- drivers/cxl/core/port.c | 26 ++++++++++++++++++++++++++ 3 files changed, 29 insertions(+), 14 deletions(-) diff --git a/drivers/cxl/core/core.h b/drivers/cxl/core/core.h index 35eaf636adc9..983d7690c3a5 100644 --- a/drivers/cxl/core/core.h +++ b/drivers/cxl/core/core.h @@ -157,6 +157,7 @@ long cxl_pci_get_latency(struct pci_dev *pdev); int cxl_pci_get_bandwidth(struct pci_dev *pdev, struct access_coordinate *c); int cxl_port_get_switch_dport_bandwidth(struct cxl_port *port, struct access_coordinate *c); +struct pci_dev *cxl_port_get_uport_pci_dev(struct cxl_port *port); static inline struct device *port_to_host(struct cxl_port *port) { diff --git a/drivers/cxl/core/pci.c b/drivers/cxl/core/pci.c index 9d807c1a002c..c3c41efae5fd 100644 --- a/drivers/cxl/core/pci.c +++ b/drivers/cxl/core/pci.c @@ -564,26 +564,14 @@ static unsigned char cdat_checksum(void *buf, size_t size) */ void read_cdat_data(struct cxl_port *port) { - struct device *uport = port->uport_dev; + struct pci_dev *pdev __free(pci_dev_put) = + cxl_port_get_uport_pci_dev(port); struct device *dev = &port->dev; struct pci_doe_mb *doe_mb; - struct pci_dev *pdev = NULL; - struct cxl_memdev *cxlmd; struct cdat_doe_rsp *buf; size_t table_length, length; int rc; - if (is_cxl_memdev(uport)) { - struct device *host; - - cxlmd = to_cxl_memdev(uport); - host = cxlmd->dev.parent; - if (dev_is_pci(host)) - pdev = to_pci_dev(host); - } else if (dev_is_pci(uport)) { - pdev = to_pci_dev(uport); - } - if (!pdev) return; diff --git a/drivers/cxl/core/port.c b/drivers/cxl/core/port.c index 625e4aa427db..5dc2815d82d8 100644 --- a/drivers/cxl/core/port.c +++ b/drivers/cxl/core/port.c @@ -34,6 +34,32 @@ static DEFINE_IDA(cxl_port_ida); static DEFINE_XARRAY(cxl_root_buses); +/** + * cxl_port_get_uport_pci_dev - get the PCI device for a port's upstream device + * @port: CXL port to map to a PCI device + * + * Return: A referenced PCI device, or NULL if the upstream device is not PCI. + * The caller must release the returned reference with pci_dev_put(). + */ +struct pci_dev *cxl_port_get_uport_pci_dev(struct cxl_port *port) +{ + struct device *uport = port->uport_dev; + struct device *host; + + if (is_cxl_memdev(uport)) { + struct cxl_memdev *cxlmd = to_cxl_memdev(uport); + + host = cxlmd->dev.parent; + } else { + host = uport; + } + + if (!host || !dev_is_pci(host)) + return NULL; + + return pci_dev_get(to_pci_dev(host)); +} + /* * The terminal device in PCI is NULL and @platform_bus * for platform devices (for cxl_test) -- 2.43.0