[v8,08/27] cxl: add functions for resource request/release by a driver

Commit Message

Lucero Palau, Alejandro Dec. 16, 2024, 4:10 p.m. UTC

From: Alejandro Lucero <[e-mail]>

Create accessors for an accel driver requesting and releasing a resource.

Signed-off-by: Alejandro Lucero <[e-mail]>
Reviewed-by: Ben Cheatham <[e-mail]>
Reviewed-by: Zhi Wang <[e-mail]>
Reviewed-by: Fan Ni <[e-mail]>
---
 drivers/cxl/core/memdev.c | 45 +++++++++++++++++++++++++++++++++++++++
 include/cxl/cxl.h         |  2 ++
 2 files changed, 47 insertions(+)

Patch

diff --git a/drivers/cxl/core/memdev.c b/drivers/cxl/core/memdev.c
index 99f533caae1e..c414b0fbbead 100644
--- a/drivers/cxl/core/memdev.c
+++ b/drivers/cxl/core/memdev.c
@@ -744,6 +744,51 @@  int cxl_set_resource(struct cxl_dev_state *cxlds, struct resource res,
 }
 EXPORT_SYMBOL_NS_GPL(cxl_set_resource, "CXL");
 
+int cxl_request_resource(struct cxl_dev_state *cxlds, enum cxl_resource type)
+{
+	switch (type) {
+	case CXL_RES_RAM:
+		if (!resource_size(&cxlds->ram_res)) {
+			dev_err(cxlds->dev,
+				"resource request for ram with size 0\n");
+			return -EINVAL;
+		}
+
+		return request_resource(&cxlds->dpa_res, &cxlds->ram_res);
+	case CXL_RES_PMEM:
+		if (!resource_size(&cxlds->pmem_res)) {
+			dev_err(cxlds->dev,
+				"resource request for pmem with size 0\n");
+			return -EINVAL;
+		}
+		return request_resource(&cxlds->dpa_res, &cxlds->pmem_res);
+	default:
+		dev_err(cxlds->dev, "unsupported resource type (%u)\n", type);
+		return -EINVAL;
+	}
+}
+EXPORT_SYMBOL_NS_GPL(cxl_request_resource, "CXL");
+
+int cxl_release_resource(struct cxl_dev_state *cxlds, enum cxl_resource type)
+{
+	int rc;
+
+	switch (type) {
+	case CXL_RES_RAM:
+		rc = release_resource(&cxlds->ram_res);
+		break;
+	case CXL_RES_PMEM:
+		rc = release_resource(&cxlds->pmem_res);
+		break;
+	default:
+		dev_err(cxlds->dev, "unknown resource type (%u)\n", type);
+		return -EINVAL;
+	}
+
+	return rc;
+}
+EXPORT_SYMBOL_NS_GPL(cxl_release_resource, "CXL");
+
 static int cxl_memdev_release_file(struct inode *inode, struct file *file)
 {
 	struct cxl_memdev *cxlmd =
diff --git a/include/cxl/cxl.h b/include/cxl/cxl.h
index 18fb01adcf19..44664c9928a4 100644
--- a/include/cxl/cxl.h
+++ b/include/cxl/cxl.h
@@ -42,4 +42,6 @@  bool cxl_pci_check_caps(struct cxl_dev_state *cxlds,
 			unsigned long *expected_caps,
 			unsigned long *current_caps);
 int cxl_pci_accel_setup_regs(struct pci_dev *pdev, struct cxl_dev_state *cxlds);
+int cxl_request_resource(struct cxl_dev_state *cxlds, enum cxl_resource type);
+int cxl_release_resource(struct cxl_dev_state *cxlds, enum cxl_resource type);
 #endif