efivars: Parameterize operations.

Instead of letting efivars access struct efi directly when dealing with
variables, use an operations structure.  This allows a later change to
reuse the efivars logic without having to pretend to support everything
in struct efi.

Signed-off-by: Mike Waychison <mikew@google.com>
Cc: Matt Domsch <Matt_Domsch@dell.com>,
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

1 files changed, 37 insertions, 24 deletions

diff --git a/drivers/firmware/efivars.c b/drivers/firmware/efivars.c
index f22bfcf2b968..b10b7d7bd7de 100644
--- a/drivers/firmware/efivars.c
+++ b/drivers/firmware/efivars.c
@@ -89,19 +89,26 @@ MODULE_DESCRIPTION("sysfs interface to EFI Variables");
 MODULE_LICENSE("GPL");
 MODULE_VERSION(EFIVARS_VERSION);
 
+struct efivar_operations {
+        efi_get_variable_t *get_variable;
+        efi_get_next_variable_t *get_next_variable;
+        efi_set_variable_t *set_variable;
+};
+
 struct efivars {
         /*
          * ->lock protects two things:
          * 1) ->list - adds, removals, reads, writes
-         * 2) efi.[gs]et_variable() calls.
+         * 2) ops.[gs]et_variable() calls.
          * It must not be held when creating sysfs entries or calling kmalloc.
-         * efi.get_next_variable() is only called from register_efivars(),
+         * ops.get_next_variable() is only called from register_efivars(),
          * which is protected by the BKL, so that path is safe.
          */
         spinlock_t lock;
         struct list_head list;
         struct kset *kset;
         struct bin_attribute *new_var, *del_var;
+        const struct efivar_operations *ops;
 };
 
 /*
@@ -182,11 +189,11 @@ get_var_data(struct efivars *efivars, struct efi_variable *var)
 
         spin_lock(&efivars->lock);
         var->DataSize = 1024;
-        status = efi.get_variable(var->VariableName,
-                                &var->VendorGuid,
-                                &var->Attributes,
-                                &var->DataSize,
-                                var->Data);
+        status = efivars->ops->get_variable(var->VariableName,
+                                            &var->VendorGuid,
+                                            &var->Attributes,
+                                            &var->DataSize,
+                                            var->Data);
         spin_unlock(&efivars->lock);
         if (status != EFI_SUCCESS) {
                 printk(KERN_WARNING "efivars: get_variable() failed 0x%lx!\n",
@@ -299,11 +306,11 @@ efivar_store_raw(struct efivar_entry *entry, const char *buf, size_t count)
         }
 
         spin_lock(&efivars->lock);
-        status = efi.set_variable(new_var->VariableName,
-                                        &new_var->VendorGuid,
-                                        new_var->Attributes,
-                                        new_var->DataSize,
-                                        new_var->Data);
+        status = efivars->ops->set_variable(new_var->VariableName,
+                                            &new_var->VendorGuid,
+                                            new_var->Attributes,
+                                            new_var->DataSize,
+                                            new_var->Data);
 
         spin_unlock(&efivars->lock);
 
@@ -446,11 +453,11 @@ static ssize_t efivar_create(struct file *filp, struct kobject *kobj,
         }
 
         /* now *really* create the variable via EFI */
-        status = efi.set_variable(new_var->VariableName,
-                        &new_var->VendorGuid,
-                        new_var->Attributes,
-                        new_var->DataSize,
-                        new_var->Data);
+        status = efivars->ops->set_variable(new_var->VariableName,
+                                            &new_var->VendorGuid,
+                                            new_var->Attributes,
+                                            new_var->DataSize,
+                                            new_var->Data);
 
         if (status != EFI_SUCCESS) {
                 printk(KERN_WARNING "efivars: set_variable() failed: status=%lx\n",
@@ -511,11 +518,11 @@ static ssize_t efivar_delete(struct file *filp, struct kobject *kobj,
         del_var->Attributes = 0;
         del_var->DataSize = 0;
 
-        status = efi.set_variable(del_var->VariableName,
-                        &del_var->VendorGuid,
-                        del_var->Attributes,
-                        del_var->DataSize,
-                        del_var->Data);
+        status = efivars->ops->set_variable(del_var->VariableName,
+                                            &del_var->VendorGuid,
+                                            del_var->Attributes,
+                                            del_var->DataSize,
+                                            del_var->Data);
 
         if (status != EFI_SUCCESS) {
                 printk(KERN_WARNING "efivars: set_variable() failed: status=%lx\n",
@@ -719,6 +726,7 @@ static void unregister_efivars(struct efivars *efivars)
 }
 
 static int register_efivars(struct efivars *efivars,
+                            const struct efivar_operations *ops,
                             struct kobject *parent_kobj)
 {
         efi_status_t status = EFI_NOT_FOUND;
@@ -735,6 +743,7 @@ static int register_efivars(struct efivars *efivars,
 
         spin_lock_init(&efivars->lock);
         INIT_LIST_HEAD(&efivars->list);
+        efivars->ops = ops;
 
         efivars->kset = kset_create_and_add("vars", NULL, parent_kobj);
         if (!efivars->kset) {
@@ -751,7 +760,7 @@ static int register_efivars(struct efivars *efivars,
         do {
                 variable_name_size = 1024;
 
-                status = efi.get_next_variable(&variable_name_size,
+                status = ops->get_next_variable(&variable_name_size,
                                                 variable_name,
                                                 &vendor_guid);
                 switch (status) {
@@ -782,6 +791,7 @@ out:
 }
 
 static struct efivars __efivars;
+static struct efivar_operations ops;
 
 /*
  * For now we register the efi subsystem with the firmware subsystem
@@ -809,7 +819,10 @@ efivars_init(void)
                 return -ENOMEM;
         }
 
-        error = register_efivars(&__efivars, efi_kobj);
+        ops.get_variable = efi.get_variable;
+        ops.set_variable = efi.set_variable;
+        ops.get_next_variable = efi.get_next_variable;
+        error = register_efivars(&__efivars, &ops, efi_kobj);
 
         /* Don't forget the systab entry */
         error = sysfs_create_group(efi_kobj, &efi_subsys_attr_group);