Re: [PATCH] ocxl: Clarify error path in setup_xsl_irq()

[Andrew Donnellan]

On 11/12/18 2:18 am, Greg Kurz wrote:

Implementing rollback with goto and labels is a common practice that
leads to prettier and more maintainable code. FWIW, this design pattern
is already being used in alloc_link() a few lines below in this file.

Do the same in setup_xsl_irq().

Signed-off-by: Greg Kurz <gr...@kaod.org>

This is good, thanks.

Acked-by: Andrew Donnellan <andrew.donnel...@au1.ibm.com>

---
  drivers/misc/ocxl/link.c |   23 ++++++++++++++---------
  1 file changed, 14 insertions(+), 9 deletions(-)

diff --git a/drivers/misc/ocxl/link.c b/drivers/misc/ocxl/link.c
index eed92055184d..659977a17405 100644
--- a/drivers/misc/ocxl/link.c
+++ b/drivers/misc/ocxl/link.c
@@ -273,9 +273,9 @@ static int setup_xsl_irq(struct pci_dev *dev, struct link 
*link)
        spa->irq_name = kasprintf(GFP_KERNEL, "ocxl-xsl-%x-%x-%x",
                                link->domain, link->bus, link->dev);
        if (!spa->irq_name) {
-               unmap_irq_registers(spa);
                dev_err(&dev->dev, "Can't allocate name for xsl interrupt\n");
-               return -ENOMEM;
+               rc = -ENOMEM;
+               goto err_xsl;
        }
        /*
         * At some point, we'll need to look into allowing a higher
@@ -283,11 +283,10 @@ static int setup_xsl_irq(struct pci_dev *dev, struct link 
*link)
         */
        spa->virq = irq_create_mapping(NULL, hwirq);
        if (!spa->virq) {
-               kfree(spa->irq_name);
-               unmap_irq_registers(spa);
                dev_err(&dev->dev,
                        "irq_create_mapping failed for translation 
interrupt\n");
-               return -EINVAL;
+               rc = -EINVAL;
+               goto err_name;
        }

dev_dbg(&dev->dev, "hwirq %d mapped to virq %d\n", hwirq, spa->virq);

@@ -295,15 +294,21 @@ static int setup_xsl_irq(struct pci_dev *dev, struct link 
*link)
        rc = request_irq(spa->virq, xsl_fault_handler, 0, spa->irq_name,
                        link);
        if (rc) {
-               irq_dispose_mapping(spa->virq);
-               kfree(spa->irq_name);
-               unmap_irq_registers(spa);
                dev_err(&dev->dev,
                        "request_irq failed for translation interrupt: %d\n",
                        rc);
-               return -EINVAL;
+               rc = -EINVAL;
+               goto err_mapping;
        }
        return 0;
+
+err_mapping:
+       irq_dispose_mapping(spa->virq);
+err_name:
+       kfree(spa->irq_name);
+err_xsl:
+       unmap_irq_registers(spa);
+       return rc;
  }

static void release_xsl_irq(struct link *link)

--
Andrew Donnellan              OzLabs, ADL Canberra
andrew.donnel...@au1.ibm.com  IBM Australia Limited