[PATCH v4 05/11] cxl: Clean up adapter MMIO unmap path.

[Daniel Axtens]

 - MMIO pointer unmapping is guarded by a null pointer check.
   However, iounmap doesn't null the pointer, just invalidate it.
   Therefore, explicitly null the pointer after unmapping.

 - afu_desc_mmio also needs to be unmapped.

 - PCI regions are allocated in cxl_map_adapter_regs.
   Therefore they should be released in unmap, not elsewhere.

Acked-by: Cyril Bur <cyrilbur at gmail.com>
Signed-off-by: Daniel Axtens <dja at axtens.net>
---
 drivers/misc/cxl/pci.c | 24 ++++++++++++++++++------
 1 file changed, 18 insertions(+), 6 deletions(-)

diff --git a/drivers/misc/cxl/pci.c b/drivers/misc/cxl/pci.c
index 62a762d94de3..484d35a5aead 100644
--- a/drivers/misc/cxl/pci.c
+++ b/drivers/misc/cxl/pci.c
@@ -539,10 +539,18 @@ err:
 
 static void cxl_unmap_slice_regs(struct cxl_afu *afu)
 {
-	if (afu->p2n_mmio)
+	if (afu->p2n_mmio) {
 		iounmap(afu->p2n_mmio);
-	if (afu->p1n_mmio)
+		afu->p2n_mmio = NULL;
+	}
+	if (afu->p1n_mmio) {
 		iounmap(afu->p1n_mmio);
+		afu->p1n_mmio = NULL;
+	}
+	if (afu->afu_desc_mmio) {
+		iounmap(afu->afu_desc_mmio);
+		afu->afu_desc_mmio = NULL;
+	}
 }
 
 static void cxl_release_afu(struct device *dev)
@@ -919,10 +927,16 @@ err1:
 
 static void cxl_unmap_adapter_regs(struct cxl *adapter)
 {
-	if (adapter->p1_mmio)
+	if (adapter->p1_mmio) {
 		iounmap(adapter->p1_mmio);
-	if (adapter->p2_mmio)
+		adapter->p1_mmio = NULL;
+		pci_release_region(to_pci_dev(adapter->dev.parent), 2);
+	}
+	if (adapter->p2_mmio) {
 		iounmap(adapter->p2_mmio);
+		adapter->p2_mmio = NULL;
+		pci_release_region(to_pci_dev(adapter->dev.parent), 0);
+	}
 }
 
 static int cxl_read_vsec(struct cxl *adapter, struct pci_dev *dev)
@@ -1131,8 +1145,6 @@ static void cxl_remove_adapter(struct cxl *adapter)
 
 	device_unregister(&adapter->dev);
 
-	pci_release_region(pdev, 0);
-	pci_release_region(pdev, 2);
 	pci_disable_device(pdev);
 }
 
-- 
2.1.4