drivers/gpu/drm/i915/gt/st_shmem_utils.c

   1 // SPDX-License-Identifier: MIT
   2 /*
   3  * Copyright © 2020 Intel Corporation
   4  */
   5
   6 /* Just a quick and causal check of the shmem_utils API */
   7
   8 static int igt_shmem_basic(void *ignored)
   9 {
  10         u32 datum = 0xdeadbeef, result;
  11         struct file *file;
  12         u32 *map;
  13         int err;
  14
  15         file = shmem_create_from_data("mock", &datum, sizeof(datum));
  16         if (IS_ERR(file))
  17                 return PTR_ERR(file);
  18
  19         result = 0;
  20         err = shmem_read(file, 0, &result, sizeof(result));
  21         if (err)
  22                 goto out_file;
  23
  24         if (result != datum) {
  25                 pr_err("Incorrect read back from shmemfs: %x != %x\n",
  26                        result, datum);
  27                 err = -EINVAL;
  28                 goto out_file;
  29         }
  30
  31         result = 0xc0ffee;
  32         err = shmem_write(file, 0, &result, sizeof(result));
  33         if (err)
  34                 goto out_file;
  35
  36         map = shmem_pin_map(file);
  37         if (!map) {
  38                 err = -ENOMEM;
  39                 goto out_file;
  40         }
  41
  42         if (*map != result) {
  43                 pr_err("Incorrect read back via mmap of last write: %x != %x\n",
  44                        *map, result);
  45                 err = -EINVAL;
  46                 goto out_map;
  47         }
  48
  49 out_map:
  50         shmem_unpin_map(file, map);
  51 out_file:
  52         fput(file);
  53         return err;
  54 }
  55
  56 int shmem_utils_mock_selftests(void)
  57 {
  58         static const struct i915_subtest tests[] = {
  59                 SUBTEST(igt_shmem_basic),
  60         };
  61
  62         return i915_subtests(tests, NULL);
  63 }