mm: add vm_area_add_early()

[cascardo/linux.git] / mm / vmalloc.c

diff --git a/mm/vmalloc.c b/mm/vmalloc.c
index b669aa6..3f2b592 100644 (file)
--- a/mm/vmalloc.c
+++ b/mm/vmalloc.c
@@ -1117,6 +1117,32 @@ void *vm_map_ram(struct page **pages, unsigned int count, int node, pgprot_t pro
 }
 EXPORT_SYMBOL(vm_map_ram);
 
+/**
+ * vm_area_add_early - add vmap area early during boot
+ * @vm: vm_struct to add
+ *
+ * This function is used to add fixed kernel vm area to vmlist before
+ * vmalloc_init() is called.  @vm->addr, @vm->size, and @vm->flags
+ * should contain proper values and the other fields should be zero.
+ *
+ * DO NOT USE THIS FUNCTION UNLESS YOU KNOW WHAT YOU'RE DOING.
+ */
+void __init vm_area_add_early(struct vm_struct *vm)
+{
+       struct vm_struct *tmp, **p;
+
+       BUG_ON(vmap_initialized);
+       for (p = &vmlist; (tmp = *p) != NULL; p = &tmp->next) {
+               if (tmp->addr >= vm->addr) {
+                       BUG_ON(tmp->addr < vm->addr + vm->size);
+                       break;
+               } else
+                       BUG_ON(tmp->addr + tmp->size > vm->addr);
+       }
+       vm->next = *p;
+       *p = vm;
+}
+
 /**
  * vm_area_register_early - register vmap area early during boot
  * @vm: vm_struct to register
@@ -1139,8 +1165,7 @@ void __init vm_area_register_early(struct vm_struct *vm, size_t align)
 
        vm->addr = (void *)addr;
 
-       vm->next = vmlist;
-       vmlist = vm;
+       vm_area_add_early(vm);
 }
 
 void __init vmalloc_init(void)