drivers/gpu/drm/i915/i915_query.c

   1 /*
   2  * SPDX-License-Identifier: MIT
   3  *
   4  * Copyright © 2018 Intel Corporation
   5  */
   6
   7 #include "i915_drv.h"
   8 #include "i915_query.h"
   9 #include <uapi/drm/i915_drm.h>
  10
  11 static int query_topology_info(struct drm_i915_private *dev_priv,
  12                                struct drm_i915_query_item *query_item)
  13 {
  14         const struct sseu_dev_info *sseu = &INTEL_INFO(dev_priv)->sseu;
  15         struct drm_i915_query_topology_info topo;
  16         u32 slice_length, subslice_length, eu_length, total_length;
  17
  18         if (query_item->flags != 0)
  19                 return -EINVAL;
  20
  21         if (sseu->max_slices == 0)
  22                 return -ENODEV;
  23
  24         BUILD_BUG_ON(sizeof(u8) != sizeof(sseu->slice_mask));
  25
  26         slice_length = sizeof(sseu->slice_mask);
  27         subslice_length = sseu->max_slices *
  28                 DIV_ROUND_UP(sseu->max_subslices,
  29                              sizeof(sseu->subslice_mask[0]) * BITS_PER_BYTE);
  30         eu_length = sseu->max_slices * sseu->max_subslices *
  31                 DIV_ROUND_UP(sseu->max_eus_per_subslice, BITS_PER_BYTE);
  32
  33         total_length = sizeof(topo) + slice_length + subslice_length + eu_length;
  34
  35         if (query_item->length == 0)
  36                 return total_length;
  37
  38         if (query_item->length < total_length)
  39                 return -EINVAL;
  40
  41         if (copy_from_user(&topo, u64_to_user_ptr(query_item->data_ptr),
  42                            sizeof(topo)))
  43                 return -EFAULT;
  44
  45         if (topo.flags != 0)
  46                 return -EINVAL;
  47
  48         if (!access_ok(VERIFY_WRITE, u64_to_user_ptr(query_item->data_ptr),
  49                        total_length))
  50                 return -EFAULT;
  51
  52         memset(&topo, 0, sizeof(topo));
  53         topo.max_slices = sseu->max_slices;
  54         topo.max_subslices = sseu->max_subslices;
  55         topo.max_eus_per_subslice = sseu->max_eus_per_subslice;
  56
  57         topo.subslice_offset = slice_length;
  58         topo.subslice_stride = DIV_ROUND_UP(sseu->max_subslices, BITS_PER_BYTE);
  59         topo.eu_offset = slice_length + subslice_length;
  60         topo.eu_stride =
  61                 DIV_ROUND_UP(sseu->max_eus_per_subslice, BITS_PER_BYTE);
  62
  63         if (__copy_to_user(u64_to_user_ptr(query_item->data_ptr),
  64                            &topo, sizeof(topo)))
  65                 return -EFAULT;
  66
  67         if (__copy_to_user(u64_to_user_ptr(query_item->data_ptr + sizeof(topo)),
  68                            &sseu->slice_mask, slice_length))
  69                 return -EFAULT;
  70
  71         if (__copy_to_user(u64_to_user_ptr(query_item->data_ptr +
  72                                            sizeof(topo) + slice_length),
  73                            sseu->subslice_mask, subslice_length))
  74                 return -EFAULT;
  75
  76         if (__copy_to_user(u64_to_user_ptr(query_item->data_ptr +
  77                                            sizeof(topo) +
  78                                            slice_length + subslice_length),
  79                            sseu->eu_mask, eu_length))
  80                 return -EFAULT;
  81
  82         return total_length;
  83 }
  84
  85 static int (* const i915_query_funcs[])(struct drm_i915_private *dev_priv,
  86                                         struct drm_i915_query_item *query_item) = {
  87         query_topology_info,
  88 };
  89
  90 int i915_query_ioctl(struct drm_device *dev, void *data, struct drm_file *file)
  91 {
  92         struct drm_i915_private *dev_priv = to_i915(dev);
  93         struct drm_i915_query *args = data;
  94         struct drm_i915_query_item __user *user_item_ptr =
  95                 u64_to_user_ptr(args->items_ptr);
  96         u32 i;
  97
  98         if (args->flags != 0)
  99                 return -EINVAL;
 100
 101         for (i = 0; i < args->num_items; i++, user_item_ptr++) {
 102                 struct drm_i915_query_item item;
 103                 u64 func_idx;
 104                 int ret;
 105
 106                 if (copy_from_user(&item, user_item_ptr, sizeof(item)))
 107                         return -EFAULT;
 108
 109                 if (item.query_id == 0)
 110                         return -EINVAL;
 111
 112                 func_idx = item.query_id - 1;
 113
 114                 if (func_idx < ARRAY_SIZE(i915_query_funcs))
 115                         ret = i915_query_funcs[func_idx](dev_priv, &item);
 116                 else
 117                         ret = -EINVAL;
 118
 119                 /* Only write the length back to userspace if they differ. */
 120                 if (ret != item.length && put_user(ret, &user_item_ptr->length))
 121                         return -EFAULT;
 122         }
 123
 124         return 0;
 125 }