percpu, module: implement and use is_kernel/module_percpu_address()

[safe/jmp/linux-2.6] / kernel / module.c

diff --git a/kernel/module.c b/kernel/module.c
index e7a6e53..9f8d23d 100644 (file)
--- a/kernel/module.c
+++ b/kernel/module.c
@@ -415,6 +415,40 @@ static void percpu_modcopy(struct module *mod,
                memcpy(per_cpu_ptr(mod->percpu, cpu), from, size);
 }
 
+/**
+ * is_module_percpu_address - test whether address is from module static percpu
+ * @addr: address to test
+ *
+ * Test whether @addr belongs to module static percpu area.
+ *
+ * RETURNS:
+ * %true if @addr is from module static percpu area
+ */
+bool is_module_percpu_address(unsigned long addr)
+{
+       struct module *mod;
+       unsigned int cpu;
+
+       preempt_disable();
+
+       list_for_each_entry_rcu(mod, &modules, list) {
+               if (!mod->percpu_size)
+                       continue;
+               for_each_possible_cpu(cpu) {
+                       void *start = per_cpu_ptr(mod->percpu, cpu);
+
+                       if ((void *)addr >= start &&
+                           (void *)addr < start + mod->percpu_size) {
+                               preempt_enable();
+                               return true;
+                       }
+               }
+       }
+
+       preempt_enable();
+       return false;
+}
+
 #else /* ... !CONFIG_SMP */
 
 static inline void __percpu *mod_percpu(struct module *mod)
@@ -441,6 +475,10 @@ static inline void percpu_modcopy(struct module *mod,
        /* pcpusec should be 0, and size of that section should be 0. */
        BUG_ON(size != 0);
 }
+bool is_module_percpu_address(unsigned long addr)
+{
+       return false;
+}
 
 #endif /* CONFIG_SMP */