LXR linux/drivers/tee/optee/shm

   1/*
   2 * Copyright (c) 2015, Linaro Limited
   3 * Copyright (c) 2017, EPAM Systems
   4 *
   5 * This software is licensed under the terms of the GNU General Public
   6 * License version 2, as published by the Free Software Foundation, and
   7 * may be copied, distributed, and modified under those terms.
   8 *
   9 * This program is distributed in the hope that it will be useful,
  10 * but WITHOUT ANY WARRANTY; without even the implied warranty of
  11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  12 * GNU General Public License for more details.
  13 *
  14 */
  15#include <linux/device.h>
  16#include <linux/dma-buf.h>
  17#include <linux/genalloc.h>
  18#include <linux/slab.h>
  19#include <linux/tee_drv.h>
  20#include "optee_private.h"
  21#include "optee_smc.h"
  22#include "shm_pool.h"
  23
  24static int pool_op_alloc(struct tee_shm_pool_mgr *poolm,
  25                         struct tee_shm *shm, size_t size)
  26{
  27        unsigned int order = get_order(size);
  28        struct page *page;
  29
  30        page = alloc_pages(GFP_KERNEL | __GFP_ZERO, order);
  31        if (!page)
  32                return -ENOMEM;
  33
  34        shm->kaddr = page_address(page);
  35        shm->paddr = page_to_phys(page);
  36        shm->size = PAGE_SIZE << order;
  37
  38        return 0;
  39}
  40
  41static void pool_op_free(struct tee_shm_pool_mgr *poolm,
  42                         struct tee_shm *shm)
  43{
  44        free_pages((unsigned long)shm->kaddr, get_order(shm->size));
  45        shm->kaddr = NULL;
  46}
  47
  48static void pool_op_destroy_poolmgr(struct tee_shm_pool_mgr *poolm)
  49{
  50        kfree(poolm);
  51}
  52
  53static const struct tee_shm_pool_mgr_ops pool_ops = {
  54        .alloc = pool_op_alloc,
  55        .free = pool_op_free,
  56        .destroy_poolmgr = pool_op_destroy_poolmgr,
  57};
  58
  59/**
  60 * optee_shm_pool_alloc_pages() - create page-based allocator pool
  61 *
  62 * This pool is used when OP-TEE supports dymanic SHM. In this case
  63 * command buffers and such are allocated from kernel's own memory.
  64 */
  65struct tee_shm_pool_mgr *optee_shm_pool_alloc_pages(void)
  66{
  67        struct tee_shm_pool_mgr *mgr = kzalloc(sizeof(*mgr), GFP_KERNEL);
  68
  69        if (!mgr)
  70                return ERR_PTR(-ENOMEM);
  71
  72        mgr->ops = &pool_ops;
  73
  74        return mgr;
  75}
  76