mm: split __vunmap

vunmap only needs to find and free the vmap_area and vm_strut, so open
code that there and merge the rest of the code into vfree.

Link: https://lkml.kernel.org/r/20230121071051.1143058-10-hch@lst.de
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: David Hildenbrand <david@redhat.com>
Cc: Alexander Potapenko <glider@google.com>
Cc: Andrey Konovalov <andreyknvl@gmail.com>
Cc: Andrey Ryabinin <ryabinin.a.a@gmail.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Uladzislau Rezki (Sony) <urezki@gmail.com>
Cc: Vincenzo Frascino <vincenzo.frascino@arm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

diff --git a/mm/vmalloc.c b/mm/vmalloc.c
index cb8c8cd161c8850fa57cd38df22a288e1fc70f11..11144a29665a32e7246a06910425a47e3dd39a7b 100644 (file)
--- a/mm/vmalloc.c
+++ b/mm/vmalloc.c
@@ -2651,45 +2651,6 @@ static void vm_remove_mappings(struct vm_struct *area, int deallocate_pages)
        set_area_direct_map(area, set_direct_map_default_noflush);
 }
 
-static void __vunmap(const void *addr, int deallocate_pages)
-{
-       struct vm_struct *area;
-
-       if (!addr)
-               return;
-
-       area = remove_vm_area(addr);
-       if (unlikely(!area)) {
-               WARN(1, KERN_ERR "Trying to vfree() nonexistent vm area (%p)\n",
-                               addr);
-               return;
-       }
-
-       vm_remove_mappings(area, deallocate_pages);
-
-       if (deallocate_pages) {
-               int i;
-
-               for (i = 0; i < area->nr_pages; i++) {
-                       struct page *page = area->pages[i];
-
-                       BUG_ON(!page);
-                       mod_memcg_page_state(page, MEMCG_VMALLOC, -1);
-                       /*
-                        * High-order allocs for huge vmallocs are split, so
-                        * can be freed as an array of order-0 allocations
-                        */
-                       __free_pages(page, 0);
-                       cond_resched();
-               }
-               atomic_long_sub(area->nr_pages, &nr_vmalloc_pages);
-
-               kvfree(area->pages);
-       }
-
-       kfree(area);
-}
-
 static void delayed_vfree_work(struct work_struct *w)
 {
        struct vfree_deferred *p = container_of(w, struct vfree_deferred, wq);
@@ -2742,6 +2703,9 @@ void vfree_atomic(const void *addr)
  */
 void vfree(const void *addr)
 {
+       struct vm_struct *vm;
+       int i;
+
        if (unlikely(in_interrupt())) {
                vfree_atomic(addr);
                return;
@@ -2751,8 +2715,32 @@ void vfree(const void *addr)
        kmemleak_free(addr);
        might_sleep();
 
-       if (addr)
-               __vunmap(addr, 1);
+       if (!addr)
+               return;
+
+       vm = remove_vm_area(addr);
+       if (unlikely(!vm)) {
+               WARN(1, KERN_ERR "Trying to vfree() nonexistent vm area (%p)\n",
+                               addr);
+               return;
+       }
+
+       vm_remove_mappings(vm, true);
+       for (i = 0; i < vm->nr_pages; i++) {
+               struct page *page = vm->pages[i];
+
+               BUG_ON(!page);
+               mod_memcg_page_state(page, MEMCG_VMALLOC, -1);
+               /*
+                * High-order allocs for huge vmallocs are split, so
+                * can be freed as an array of order-0 allocations
+                */
+               __free_pages(page, 0);
+               cond_resched();
+       }
+       atomic_long_sub(vm->nr_pages, &nr_vmalloc_pages);
+       kvfree(vm->pages);
+       kfree(vm);
 }
 EXPORT_SYMBOL(vfree);
 
@@ -2767,10 +2755,20 @@ EXPORT_SYMBOL(vfree);
  */
 void vunmap(const void *addr)
 {
+       struct vm_struct *vm;
+
        BUG_ON(in_interrupt());
        might_sleep();
-       if (addr)
-               __vunmap(addr, 0);
+
+       if (!addr)
+               return;
+       vm = remove_vm_area(addr);
+       if (unlikely(!vm)) {
+               WARN(1, KERN_ERR "Trying to vunmap() nonexistent vm area (%p)\n",
+                               addr);
+               return;
+       }
+       kfree(vm);
 }
 EXPORT_SYMBOL(vunmap);