optee: allocate shared memory with alloc_pages_exact()

Allocate memory to share with the secure world using alloc_pages_exact()
instead of alloc_pages() for more efficient memory usage.

Reviewed-by: Sumit Garg <sumit.garg@linaro.org>
Signed-off-by: Jens Wiklander <jens.wiklander@linaro.org>

diff --git a/drivers/tee/optee/core.c b/drivers/tee/optee/core.c
index 38ea2fecfc2e8b154bd77bcc57d29c13500d53cb..4a4b03b4fc7d1e628f2d25be285b86bd87357719 100644 (file)
--- a/drivers/tee/optee/core.c
+++ b/drivers/tee/optee/core.c
@@ -26,10 +26,8 @@ int optee_pool_op_alloc_helper(struct tee_shm_pool *pool, struct tee_shm *shm,
                                                   size_t num_pages,
                                                   unsigned long start))
 {
-       unsigned int order = get_order(size);
-       unsigned int nr_pages = 1 << order;
+       size_t nr_pages = roundup(size, PAGE_SIZE) / PAGE_SIZE;
        struct page **pages;
-       struct page *page;
        unsigned int i;
        int rc = 0;
 
@@ -37,13 +35,13 @@ int optee_pool_op_alloc_helper(struct tee_shm_pool *pool, struct tee_shm *shm,
         * Ignore alignment since this is already going to be page aligned
         * and there's no need for any larger alignment.
         */
-       page = alloc_pages(GFP_KERNEL | __GFP_ZERO, order);
-       if (!page)
+       shm->kaddr = alloc_pages_exact(nr_pages * PAGE_SIZE,
+                                      GFP_KERNEL | __GFP_ZERO);
+       if (!shm->kaddr)
                return -ENOMEM;
 
-       shm->kaddr = page_address(page);
-       shm->paddr = page_to_phys(page);
-       shm->size = PAGE_SIZE << order;
+       shm->paddr = virt_to_phys(shm->kaddr);
+       shm->size = nr_pages * PAGE_SIZE;
 
        pages = kcalloc(nr_pages, sizeof(*pages), GFP_KERNEL);
        if (!pages) {
@@ -52,7 +50,7 @@ int optee_pool_op_alloc_helper(struct tee_shm_pool *pool, struct tee_shm *shm,
        }
 
        for (i = 0; i < nr_pages; i++)
-               pages[i] = page + i;
+               pages[i] = virt_to_page((u8 *)shm->kaddr + i * PAGE_SIZE);
 
        shm->pages = pages;
        shm->num_pages = nr_pages;
@@ -66,7 +64,7 @@ int optee_pool_op_alloc_helper(struct tee_shm_pool *pool, struct tee_shm *shm,
 
        return 0;
 err:
-       free_pages((unsigned long)shm->kaddr, order);
+       free_pages_exact(shm->kaddr, shm->size);
        shm->kaddr = NULL;
        return rc;
 }
@@ -77,7 +75,7 @@ void optee_pool_op_free_helper(struct tee_shm_pool *pool, struct tee_shm *shm,
 {
        if (shm_unregister)
                shm_unregister(shm->ctx, shm);
-       free_pages((unsigned long)shm->kaddr, get_order(shm->size));
+       free_pages_exact(shm->kaddr, shm->size);
        shm->kaddr = NULL;
        kfree(shm->pages);
        shm->pages = NULL;