drivers/tee/amdtee/shm_pool.c

   1 // SPDX-License-Identifier: MIT
   2 /*
   3  * Copyright 2019 Advanced Micro Devices, Inc.
   4  */
   5
   6 #include <linux/slab.h>
   7 #include <linux/tee_drv.h>
   8 #include <linux/psp-sev.h>
   9 #include "amdtee_private.h"
  10
  11 static int pool_op_alloc(struct tee_shm_pool_mgr *poolm, struct tee_shm *shm,
  12                          size_t size)
  13 {
  14         unsigned int order = get_order(size);
  15         unsigned long va;
  16         int rc;
  17
  18         va = __get_free_pages(GFP_KERNEL | __GFP_ZERO, order);
  19         if (!va)
  20                 return -ENOMEM;
  21
  22         shm->kaddr = (void *)va;
  23         shm->paddr = __psp_pa((void *)va);
  24         shm->size = PAGE_SIZE << order;
  25
  26         /* Map the allocated memory in to TEE */
  27         rc = amdtee_map_shmem(shm);
  28         if (rc) {
  29                 free_pages(va, order);
  30                 shm->kaddr = NULL;
  31                 return rc;
  32         }
  33
  34         return 0;
  35 }
  36
  37 static void pool_op_free(struct tee_shm_pool_mgr *poolm, struct tee_shm *shm)
  38 {
  39         /* Unmap the shared memory from TEE */
  40         amdtee_unmap_shmem(shm);
  41         free_pages((unsigned long)shm->kaddr, get_order(shm->size));
  42         shm->kaddr = NULL;
  43 }
  44
  45 static void pool_op_destroy_poolmgr(struct tee_shm_pool_mgr *poolm)
  46 {
  47         kfree(poolm);
  48 }
  49
  50 static const struct tee_shm_pool_mgr_ops pool_ops = {
  51         .alloc = pool_op_alloc,
  52         .free = pool_op_free,
  53         .destroy_poolmgr = pool_op_destroy_poolmgr,
  54 };
  55
  56 static struct tee_shm_pool_mgr *pool_mem_mgr_alloc(void)
  57 {
  58         struct tee_shm_pool_mgr *mgr = kzalloc(sizeof(*mgr), GFP_KERNEL);
  59
  60         if (!mgr)
  61                 return ERR_PTR(-ENOMEM);
  62
  63         mgr->ops = &pool_ops;
  64
  65         return mgr;
  66 }
  67
  68 struct tee_shm_pool *amdtee_config_shm(void)
  69 {
  70         struct tee_shm_pool_mgr *priv_mgr;
  71         struct tee_shm_pool_mgr *dmabuf_mgr;
  72         void *rc;
  73
  74         rc = pool_mem_mgr_alloc();
  75         if (IS_ERR(rc))
  76                 return rc;
  77         priv_mgr = rc;
  78
  79         rc = pool_mem_mgr_alloc();
  80         if (IS_ERR(rc)) {
  81                 tee_shm_pool_mgr_destroy(priv_mgr);
  82                 return rc;
  83         }
  84         dmabuf_mgr = rc;
  85
  86         rc = tee_shm_pool_alloc(priv_mgr, dmabuf_mgr);
  87         if (IS_ERR(rc)) {
  88                 tee_shm_pool_mgr_destroy(priv_mgr);
  89                 tee_shm_pool_mgr_destroy(dmabuf_mgr);
  90         }
  91
  92         return rc;
  93 }