ocxl: Create a clear delineation between ocxl backend & frontend

The OCXL driver contains both frontend code for interacting with userspace,
as well as backend code for interacting with the hardware.

This patch separates the backend code from the frontend so that it can be
used by other device drivers that communicate via OpenCAPI.

Relocate dev, cdev & sysfs files to the frontend code to allow external
drivers to maintain their own devices.

Reference counting on the device in the backend is replaced with kref
counting.

Move file & sysfs layer initialisation from core.c (backend) to
pci.c (frontend).

Create an ocxl_function oriented interface for initing devices &
enumerating AFUs.

Signed-off-by: Alastair D'Silva <alastair@d-silva.org>
Acked-by: Frederic Barrat <fbarrat@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

1 files changed, 27 insertions, 29 deletions

diff --git a/drivers/misc/ocxl/pci.c b/drivers/misc/ocxl/pci.c
index 4ed7cb1a667f..f2a3ef4b9bdd 100644
--- a/drivers/misc/ocxl/pci.c
+++ b/drivers/misc/ocxl/pci.c
@@ -16,47 +16,45 @@ MODULE_DEVICE_TABLE(pci, ocxl_pci_tbl);
 
 static int ocxl_probe(struct pci_dev *dev, const struct pci_device_id *id)
 {
-	int rc, afu_count = 0;
-	u8 afu;
+	int rc;
+	struct ocxl_afu *afu, *tmp;
 	struct ocxl_fn *fn;
+	struct list_head *afu_list;
 
-	if (!radix_enabled()) {
-		dev_err(&dev->dev, "Unsupported memory model (hash)\n");
-		return -ENODEV;
-	}
-
-	fn = init_function(dev);
-	if (IS_ERR(fn)) {
-		dev_err(&dev->dev, "function init failed: %li\n",
-			PTR_ERR(fn));
+	fn = ocxl_function_open(dev);
+	if (IS_ERR(fn))
 		return PTR_ERR(fn);
-	}
 
-	for (afu = 0; afu <= fn->config.max_afu_index; afu++) {
-		rc = ocxl_config_check_afu_index(dev, &fn->config, afu);
-		if (rc > 0) {
-			rc = init_afu(dev, fn, afu);
-			if (rc) {
-				dev_err(&dev->dev,
-					"Can't initialize AFU index %d\n", afu);
-				continue;
-			}
-			afu_count++;
+	pci_set_drvdata(dev, fn);
+
+	afu_list = ocxl_function_afu_list(fn);
+
+	list_for_each_entry_safe(afu, tmp, afu_list, list) {
+		// Cleanup handled within ocxl_file_register_afu()
+		rc = ocxl_file_register_afu(afu);
+		if (rc) {
+			dev_err(&dev->dev, "Failed to register AFU '%s' index %d",
+					afu->config.name, afu->config.idx);
 		}
 	}
-	dev_info(&dev->dev, "%d AFU(s) configured\n", afu_count);
+
 	return 0;
 }
 
-static void ocxl_remove(struct pci_dev *dev)
+void ocxl_remove(struct pci_dev *dev)
 {
-	struct ocxl_afu *afu, *tmp;
-	struct ocxl_fn *fn = pci_get_drvdata(dev);
+	struct ocxl_fn *fn;
+	struct ocxl_afu *afu;
+	struct list_head *afu_list;
 
-	list_for_each_entry_safe(afu, tmp, &fn->afu_list, list) {
-		remove_afu(afu);
+	fn = pci_get_drvdata(dev);
+	afu_list = ocxl_function_afu_list(fn);
+
+	list_for_each_entry(afu, afu_list, list) {
+		ocxl_file_unregister_afu(afu);
 	}
-	remove_function(fn);
+
+	ocxl_function_close(fn);
 }
 
 struct pci_driver ocxl_pci_driver = {