platform-msi: Factor out allocation/free of private data

As we're going to have multiple paths to allocate/free the
platform-msi private data, factor this out into separate
utility functions.

Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>

1 files changed, 53 insertions, 41 deletions

diff --git a/drivers/base/platform-msi.c b/drivers/base/platform-msi.c
index 6148c78f51a7..44b8c0d816fe 100644
--- a/drivers/base/platform-msi.c
+++ b/drivers/base/platform-msi.c
@@ -189,21 +189,11 @@ struct irq_domain *platform_msi_create_irq_domain(struct fwnode_handle *fwnode,
         return domain;
 }
 
-/**
- * platform_msi_domain_alloc_irqs - Allocate MSI interrupts for @dev
- * @dev:                The device for which to allocate interrupts
- * @nvec:               The number of interrupts to allocate
- * @write_msi_msg:      Callback to write an interrupt message for @dev
- *
- * Returns:
- * Zero for success, or an error code in case of failure
- */
-int platform_msi_domain_alloc_irqs(struct device *dev, unsigned int nvec,
-                                   irq_write_msi_msg_t write_msi_msg)
+static struct platform_msi_priv_data *
+platform_msi_alloc_priv_data(struct device *dev, unsigned int nvec,
+                             irq_write_msi_msg_t write_msi_msg)
 {
-        struct platform_msi_priv_data *priv_data;
-        int err;
-
+        struct platform_msi_priv_data *datap;
         /*
          * Limit the number of interrupts to 256 per device. Should we
          * need to bump this up, DEV_ID_SHIFT should be adjusted
@@ -211,33 +201,62 @@ int platform_msi_domain_alloc_irqs(struct device *dev, unsigned int nvec,
          * capable devices).
          */
         if (!dev->msi_domain || !write_msi_msg || !nvec || nvec > MAX_DEV_MSIS)
-                return -EINVAL;
+                return ERR_PTR(-EINVAL);
 
         if (dev->msi_domain->bus_token != DOMAIN_BUS_PLATFORM_MSI) {
                 dev_err(dev, "Incompatible msi_domain, giving up\n");
-                return -EINVAL;
+                return ERR_PTR(-EINVAL);
         }
 
         /* Already had a helping of MSI? Greed... */
         if (!list_empty(dev_to_msi_list(dev)))
-                return -EBUSY;
+                return ERR_PTR(-EBUSY);
+
+        datap = kzalloc(sizeof(*datap), GFP_KERNEL);
+        if (!datap)
+                return ERR_PTR(-ENOMEM);
+
+        datap->devid = ida_simple_get(&platform_msi_devid_ida,
+                                      0, 1 << DEV_ID_SHIFT, GFP_KERNEL);
+        if (datap->devid < 0) {
+                int err = datap->devid;
+                kfree(datap);
+                return ERR_PTR(err);
+        }
 
-        priv_data = kzalloc(sizeof(*priv_data), GFP_KERNEL);
-        if (!priv_data)
-                return -ENOMEM;
+        datap->write_msg = write_msi_msg;
 
-        priv_data->devid = ida_simple_get(&platform_msi_devid_ida,
-                                          0, 1 << DEV_ID_SHIFT, GFP_KERNEL);
-        if (priv_data->devid < 0) {
-                err = priv_data->devid;
-                goto out_free_data;
-        }
+        return datap;
+}
+
+static void platform_msi_free_priv_data(struct platform_msi_priv_data *data)
+{
+        ida_simple_remove(&platform_msi_devid_ida, data->devid);
+        kfree(data);
+}
+
+/**
+ * platform_msi_domain_alloc_irqs - Allocate MSI interrupts for @dev
+ * @dev:                The device for which to allocate interrupts
+ * @nvec:               The number of interrupts to allocate
+ * @write_msi_msg:      Callback to write an interrupt message for @dev
+ *
+ * Returns:
+ * Zero for success, or an error code in case of failure
+ */
+int platform_msi_domain_alloc_irqs(struct device *dev, unsigned int nvec,
+                                   irq_write_msi_msg_t write_msi_msg)
+{
+        struct platform_msi_priv_data *priv_data;
+        int err;
 
-        priv_data->write_msg = write_msi_msg;
+        priv_data = platform_msi_alloc_priv_data(dev, nvec, write_msi_msg);
+        if (IS_ERR(priv_data))
+                return PTR_ERR(priv_data);
 
         err = platform_msi_alloc_descs(dev, nvec, priv_data);
         if (err)
-                goto out_free_id;
+                goto out_free_priv_data;
 
         err = msi_domain_alloc_irqs(dev->msi_domain, dev, nvec);
         if (err)
@@ -247,10 +266,8 @@ int platform_msi_domain_alloc_irqs(struct device *dev, unsigned int nvec,
 
 out_free_desc:
         platform_msi_free_descs(dev, 0, nvec);
-out_free_id:
-        ida_simple_remove(&platform_msi_devid_ida, priv_data->devid);
-out_free_data:
-        kfree(priv_data);
+out_free_priv_data:
+        platform_msi_free_priv_data(priv_data);
 
         return err;
 }
@@ -261,16 +278,11 @@ out_free_data:
  */
 void platform_msi_domain_free_irqs(struct device *dev)
 {
-        struct msi_desc *desc;
-
-        desc = first_msi_entry(dev);
-        if (desc) {
-                struct platform_msi_priv_data *data;
-
-                data = desc->platform.msi_priv_data;
+        if (!list_empty(dev_to_msi_list(dev))) {
+                struct msi_desc *desc;
 
-                ida_simple_remove(&platform_msi_devid_ida, data->devid);
-                kfree(data);
+                desc = first_msi_entry(dev);
+                platform_msi_free_priv_data(desc->platform.msi_priv_data);
         }
 
         msi_domain_free_irqs(dev->msi_domain, dev);