Commit 79311c1f authored by Christoph Hellwig's avatar Christoph Hellwig Committed by Andrew Morton
Browse files

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: default avatarChristoph Hellwig <hch@lst.de>
Reviewed-by: default avatarDavid 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: default avatarAndrew Morton <akpm@linux-foundation.org>
parent 17d3ef43

mm/vmalloc.c

+41 −43
Original line number Diff line number Diff line
@@ -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);