ipmi: Use a temporary BMC for an interface

[mirror_ubuntu-bionic-kernel.git] / drivers / char / ipmi / ipmi_msghandler.c

diff --git a/drivers/char/ipmi/ipmi_msghandler.c b/drivers/char/ipmi/ipmi_msghandler.c
index 98318b965de78de628eddc87d9dc06ab8137d793..9d4a9a94fdc64584cab103a3f32a2cd9ef77071a 100644 (file)
--- a/drivers/char/ipmi/ipmi_msghandler.c
+++ b/drivers/char/ipmi/ipmi_msghandler.c
@@ -418,6 +418,7 @@ struct ipmi_smi {
         */
        struct mutex bmc_reg_mutex;
 
+       struct bmc_device tmp_bmc;
        struct bmc_device *bmc;
        bool bmc_registered;
        struct list_head bmc_link;
@@ -2839,7 +2840,7 @@ static void ipmi_bmc_unregister(ipmi_smi_t intf)
        mutex_lock(&bmc->dyn_mutex);
        list_del(&intf->bmc_link);
        mutex_unlock(&bmc->dyn_mutex);
-       intf->bmc = NULL;
+       intf->bmc = &intf->tmp_bmc;
        mutex_lock(&ipmidriver_mutex);
        kref_put(&bmc->usecount, cleanup_bmc_device);
        mutex_unlock(&ipmidriver_mutex);
@@ -2872,7 +2873,6 @@ static int ipmi_bmc_register(ipmi_smi_t intf, int ifnum)
         * otherwise register the new BMC device
         */
        if (old_bmc) {
-               kfree(bmc);
                bmc = old_bmc;
                intf->bmc = old_bmc;
                mutex_lock(&bmc->dyn_mutex);
@@ -2886,6 +2886,14 @@ static int ipmi_bmc_register(ipmi_smi_t intf, int ifnum)
                       bmc->id.product_id,
                       bmc->id.device_id);
        } else {
+               bmc = kzalloc(sizeof(*bmc), GFP_KERNEL);
+               if (!bmc) {
+                       rv = -ENOMEM;
+                       goto out;
+               }
+               INIT_LIST_HEAD(&bmc->intfs);
+               mutex_init(&bmc->dyn_mutex);
+
                bmc->pdev.name = "ipmi_bmc";
 
                rv = ida_simple_get(&ipmi_bmc_ida, 0, 0, GFP_KERNEL);
@@ -2968,7 +2976,7 @@ out_put_bmc:
        mutex_lock(&bmc->dyn_mutex);
        list_del(&intf->bmc_link);
        mutex_unlock(&bmc->dyn_mutex);
-       intf->bmc = NULL;
+       intf->bmc = &intf->tmp_bmc;
        mutex_lock(&ipmidriver_mutex);
        kref_put(&bmc->usecount, cleanup_bmc_device);
        mutex_unlock(&ipmidriver_mutex);
@@ -2978,7 +2986,7 @@ out_list_del:
        mutex_lock(&bmc->dyn_mutex);
        list_del(&intf->bmc_link);
        mutex_unlock(&bmc->dyn_mutex);
-       intf->bmc = NULL;
+       intf->bmc = &intf->tmp_bmc;
        put_device(&bmc->pdev.dev);
        goto out;
 }
@@ -3204,11 +3212,7 @@ int ipmi_register_smi(const struct ipmi_smi_handlers *handlers,
        if (!intf)
                return -ENOMEM;
 
-       intf->bmc = kzalloc(sizeof(*intf->bmc), GFP_KERNEL);
-       if (!intf->bmc) {
-               kfree(intf);
-               return -ENOMEM;
-       }
+       intf->bmc = &intf->tmp_bmc;
        INIT_LIST_HEAD(&intf->bmc->intfs);
        mutex_init(&intf->bmc->dyn_mutex);
        INIT_LIST_HEAD(&intf->bmc_link);