Commit cbc174a6 authored by Carlos Llamas's avatar Carlos Llamas Committed by Greg Kroah-Hartman
Browse files

binder: relocate binder_alloc_clear_buf() 



Move this function up along with binder_alloc_get_page() so that their
prototypes aren't necessary.

No functional change in this patch.

Reviewed-by: default avatarAlice Ryhl <aliceryhl@google.com>
Signed-off-by: default avatarCarlos Llamas <cmllamas@google.com>
Link: https://lore.kernel.org/r/20231201172212.1813387-16-cmllamas@google.com


Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
parent c13500ea

drivers/android/binder_alloc.c

+61 −63
Original line number Diff line number Diff line
@@ -704,8 +704,68 @@ static void binder_free_buf_locked(struct binder_alloc *alloc, 
	binder_insert_free_buffer(alloc, buffer);

}



/**

 * binder_alloc_get_page() - get kernel pointer for given buffer offset

 * @alloc: binder_alloc for this proc

 * @buffer: binder buffer to be accessed

 * @buffer_offset: offset into @buffer data

 * @pgoffp: address to copy final page offset to

 *

 * Lookup the struct page corresponding to the address

 * at @buffer_offset into @buffer->user_data. If @pgoffp is not

 * NULL, the byte-offset into the page is written there.

 *

 * The caller is responsible to ensure that the offset points

 * to a valid address within the @buffer and that @buffer is

 * not freeable by the user. Since it can't be freed, we are

 * guaranteed that the corresponding elements of @alloc->pages[]

 * cannot change.

 *

 * Return: struct page

 */

static struct page *binder_alloc_get_page(struct binder_alloc *alloc,

					  struct binder_buffer *buffer,

					  binder_size_t buffer_offset,

					  pgoff_t *pgoffp)

{

	binder_size_t buffer_space_offset = buffer_offset +

		(buffer->user_data - alloc->buffer);

	pgoff_t pgoff = buffer_space_offset & ~PAGE_MASK;

	size_t index = buffer_space_offset >> PAGE_SHIFT;

	struct binder_lru_page *lru_page;



	lru_page = &alloc->pages[index];

	*pgoffp = pgoff;

	return lru_page->page_ptr;

}



/**

 * binder_alloc_clear_buf() - zero out buffer

 * @alloc: binder_alloc for this proc

 * @buffer: binder buffer to be cleared

 *

 * memset the given buffer to 0

 */

static void binder_alloc_clear_buf(struct binder_alloc *alloc,

				   struct binder_buffer *buffer);

				   struct binder_buffer *buffer)

{

	size_t bytes = binder_alloc_buffer_size(alloc, buffer);

	binder_size_t buffer_offset = 0;



	while (bytes) {

		unsigned long size;

		struct page *page;

		pgoff_t pgoff;



		page = binder_alloc_get_page(alloc, buffer,

					     buffer_offset, &pgoff);

		size = min_t(size_t, bytes, PAGE_SIZE - pgoff);

		memset_page(page, pgoff, 0, size);

		bytes -= size;

		buffer_offset += size;

	}

}



/**

 * binder_alloc_free_buf() - free a binder buffer

 * @alloc:	binder_alloc for this proc
@@ -1148,68 +1208,6 @@ static inline bool check_buffer(struct binder_alloc *alloc, 
		(!buffer->allow_user_free || !buffer->transaction);

}



/**

 * binder_alloc_get_page() - get kernel pointer for given buffer offset

 * @alloc: binder_alloc for this proc

 * @buffer: binder buffer to be accessed

 * @buffer_offset: offset into @buffer data

 * @pgoffp: address to copy final page offset to

 *

 * Lookup the struct page corresponding to the address

 * at @buffer_offset into @buffer->user_data. If @pgoffp is not

 * NULL, the byte-offset into the page is written there.

 *

 * The caller is responsible to ensure that the offset points

 * to a valid address within the @buffer and that @buffer is

 * not freeable by the user. Since it can't be freed, we are

 * guaranteed that the corresponding elements of @alloc->pages[]

 * cannot change.

 *

 * Return: struct page

 */

static struct page *binder_alloc_get_page(struct binder_alloc *alloc,

					  struct binder_buffer *buffer,

					  binder_size_t buffer_offset,

					  pgoff_t *pgoffp)

{

	binder_size_t buffer_space_offset = buffer_offset +

		(buffer->user_data - alloc->buffer);

	pgoff_t pgoff = buffer_space_offset & ~PAGE_MASK;

	size_t index = buffer_space_offset >> PAGE_SHIFT;

	struct binder_lru_page *lru_page;



	lru_page = &alloc->pages[index];

	*pgoffp = pgoff;

	return lru_page->page_ptr;

}



/**

 * binder_alloc_clear_buf() - zero out buffer

 * @alloc: binder_alloc for this proc

 * @buffer: binder buffer to be cleared

 *

 * memset the given buffer to 0

 */

static void binder_alloc_clear_buf(struct binder_alloc *alloc,

				   struct binder_buffer *buffer)

{

	size_t bytes = binder_alloc_buffer_size(alloc, buffer);

	binder_size_t buffer_offset = 0;



	while (bytes) {

		unsigned long size;

		struct page *page;

		pgoff_t pgoff;



		page = binder_alloc_get_page(alloc, buffer,

					     buffer_offset, &pgoff);

		size = min_t(size_t, bytes, PAGE_SIZE - pgoff);

		memset_page(page, pgoff, 0, size);

		bytes -= size;

		buffer_offset += size;

	}

}



/**

 * binder_alloc_copy_user_to_buffer() - copy src user to tgt user

 * @alloc: binder_alloc for this proc