cxl/mem: Convert devm_cxl_add_memdev() to scope-based-cleanup

In preparation for adding more setup steps, convert the current
implementation to scope-based cleanup.

The cxl_memdev_shutdown() is only required after cdev_device_add(). With
that moved to a helper function it precludes the need to add
scope-based-handler for that cleanup if devm_add_action_or_reset() fails.

Cc: Smita Koralahalli <Smita.KoralahalliChannabasappa@amd.com>
Reviewed-by: Alison Schofield <alison.schofield@intel.com>
Reviewed-by: Dave Jiang <dave.jiang@intel.com>
Reviewed-by: Ben Cheatham <benjamin.cheatham@amd.com>
Tested-by: Alejandro Lucero <alucerop@amd.com>
Reviewed-by: Jonathan Cameron <jonathan.cameron@huawei.com>
Link: https://patch.msgid.link/20251216005616.3090129-5-dan.j.williams@intel.com
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: Dave Jiang <dave.jiang@intel.com>

diff --git a/drivers/cxl/core/memdev.c b/drivers/cxl/core/memdev.c
index 7a4153e1c6a7869712f96d3aca97e8f0082a2ba3..92aea95859fb6fa701a3d365767c02dc12b238eb 100644 (file)
--- a/drivers/cxl/core/memdev.c
+++ b/drivers/cxl/core/memdev.c
@@ -1050,6 +1050,45 @@ static const struct file_operations cxl_memdev_fops = {
        .llseek = noop_llseek,
 };
 
+/*
+ * Activate ioctl operations, no cxl_memdev_rwsem manipulation needed as this is
+ * ordered with cdev_add() publishing the device.
+ */
+static int cxlmd_add(struct cxl_memdev *cxlmd, struct cxl_dev_state *cxlds)
+{
+       int rc;
+
+       cxlmd->cxlds = cxlds;
+       cxlds->cxlmd = cxlmd;
+
+       rc = cdev_device_add(&cxlmd->cdev, &cxlmd->dev);
+       if (rc) {
+               /*
+                * The cdev was briefly live, shutdown any ioctl operations that
+                * saw that state.
+                */
+               cxl_memdev_shutdown(&cxlmd->dev);
+               return rc;
+       }
+
+       return 0;
+}
+
+DEFINE_FREE(put_cxlmd, struct cxl_memdev *,
+           if (!IS_ERR_OR_NULL(_T)) put_device(&_T->dev))
+
+static struct cxl_memdev *cxl_memdev_autoremove(struct cxl_memdev *cxlmd)
+{
+       int rc;
+
+       rc = devm_add_action_or_reset(cxlmd->cxlds->dev, cxl_memdev_unregister,
+                                     cxlmd);
+       if (rc)
+               return ERR_PTR(rc);
+
+       return cxlmd;
+}
+
 /*
  * Core helper for devm_cxl_add_memdev() that wants to both create a device and
  * assert to the caller that upon return cxl_mem::probe() has been invoked.
@@ -1057,45 +1096,24 @@ static const struct file_operations cxl_memdev_fops = {
 struct cxl_memdev *__devm_cxl_add_memdev(struct device *host,
                                         struct cxl_dev_state *cxlds)
 {
-       struct cxl_memdev *cxlmd;
        struct device *dev;
-       struct cdev *cdev;
        int rc;
 
-       cxlmd = cxl_memdev_alloc(cxlds, &cxl_memdev_fops);
+       struct cxl_memdev *cxlmd __free(put_cxlmd) =
+               cxl_memdev_alloc(cxlds, &cxl_memdev_fops);
        if (IS_ERR(cxlmd))
                return cxlmd;
 
        dev = &cxlmd->dev;
        rc = dev_set_name(dev, "mem%d", cxlmd->id);
        if (rc)
-               goto err;
-
-       /*
-        * Activate ioctl operations, no cxl_memdev_rwsem manipulation
-        * needed as this is ordered with cdev_add() publishing the device.
-        */
-       cxlmd->cxlds = cxlds;
-       cxlds->cxlmd = cxlmd;
-
-       cdev = &cxlmd->cdev;
-       rc = cdev_device_add(cdev, dev);
-       if (rc)
-               goto err;
+               return ERR_PTR(rc);
 
-       rc = devm_add_action_or_reset(host, cxl_memdev_unregister, cxlmd);
+       rc = cxlmd_add(cxlmd, cxlds);
        if (rc)
                return ERR_PTR(rc);
-       return cxlmd;
 
-err:
-       /*
-        * The cdev was briefly live, shutdown any ioctl operations that
-        * saw that state.
-        */
-       cxl_memdev_shutdown(dev);
-       put_device(dev);
-       return ERR_PTR(rc);
+       return cxl_memdev_autoremove(no_free_ptr(cxlmd));
 }
 EXPORT_SYMBOL_FOR_MODULES(__devm_cxl_add_memdev, "cxl_mem");