LXR linux/drivers/tee/optee/shm

   1// SPDX-License-Identifier: GPL-2.0-only
   2/*
   3 * Copyright (c) 2015, Linaro Limited
   4 * Copyright (c) 2017, EPAM Systems
   5 */
   6#include <linux/device.h>
   7#include <linux/dma-buf.h>
   8#include <linux/genalloc.h>
   9#include <linux/slab.h>
  10#include <linux/tee_drv.h>
  11#include "optee_private.h"
  12#include "optee_smc.h"
  13#include "shm_pool.h"
  14
  15static int pool_op_alloc(struct tee_shm_pool_mgr *poolm,
  16                         struct tee_shm *shm, size_t size)
  17{
  18        unsigned int order = get_order(size);
  19        struct page *page;
  20        int rc = 0;
  21
  22        page = alloc_pages(GFP_KERNEL | __GFP_ZERO, order);
  23        if (!page)
  24                return -ENOMEM;
  25
  26        shm->kaddr = page_address(page);
  27        shm->paddr = page_to_phys(page);
  28        shm->size = PAGE_SIZE << order;
  29
  30        if (shm->flags & TEE_SHM_DMA_BUF) {
  31                unsigned int nr_pages = 1 << order, i;
  32                struct page **pages;
  33
  34                pages = kcalloc(nr_pages, sizeof(pages), GFP_KERNEL);
  35                if (!pages)
  36                        return -ENOMEM;
  37
  38                for (i = 0; i < nr_pages; i++) {
  39                        pages[i] = page;
  40                        page++;
  41                }
  42
  43                shm->flags |= TEE_SHM_REGISTER;
  44                rc = optee_shm_register(shm->ctx, shm, pages, nr_pages,
  45                                        (unsigned long)shm->kaddr);
  46                kfree(pages);
  47        }
  48
  49        return rc;
  50}
  51
  52static void pool_op_free(struct tee_shm_pool_mgr *poolm,
  53                         struct tee_shm *shm)
  54{
  55        if (shm->flags & TEE_SHM_DMA_BUF)
  56                optee_shm_unregister(shm->ctx, shm);
  57
  58        free_pages((unsigned long)shm->kaddr, get_order(shm->size));
  59        shm->kaddr = NULL;
  60}
  61
  62static void pool_op_destroy_poolmgr(struct tee_shm_pool_mgr *poolm)
  63{
  64        kfree(poolm);
  65}
  66
  67static const struct tee_shm_pool_mgr_ops pool_ops = {
  68        .alloc = pool_op_alloc,
  69        .free = pool_op_free,
  70        .destroy_poolmgr = pool_op_destroy_poolmgr,
  71};
  72
  73/**
  74 * optee_shm_pool_alloc_pages() - create page-based allocator pool
  75 *
  76 * This pool is used when OP-TEE supports dymanic SHM. In this case
  77 * command buffers and such are allocated from kernel's own memory.
  78 */
  79struct tee_shm_pool_mgr *optee_shm_pool_alloc_pages(void)
  80{
  81        struct tee_shm_pool_mgr *mgr = kzalloc(sizeof(*mgr), GFP_KERNEL);
  82
  83        if (!mgr)
  84                return ERR_PTR(-ENOMEM);
  85
  86        mgr->ops = &pool_ops;
  87
  88        return mgr;
  89}
  90