drivers/gpu/drm/i915/i915_query.c

   1 /*
   2  * SPDX-License-Identifier: MIT
   3  *
   4  * Copyright © 2018 Intel Corporation
   5  */
   6
   7 #include <linux/nospec.h>
   8
   9 #include "i915_drv.h"
  10 #include "i915_query.h"
  11 #include <uapi/drm/i915_drm.h>
  12
  13 static int copy_query_item(void *query_hdr, size_t query_sz,
  14                            u32 total_length,
  15                            struct drm_i915_query_item *query_item)
  16 {
  17         if (query_item->length == 0)
  18                 return total_length;
  19
  20         if (query_item->length < total_length)
  21                 return -EINVAL;
  22
  23         if (copy_from_user(query_hdr, u64_to_user_ptr(query_item->data_ptr),
  24                            query_sz))
  25                 return -EFAULT;
  26
  27         if (!access_ok(u64_to_user_ptr(query_item->data_ptr),
  28                        total_length))
  29                 return -EFAULT;
  30
  31         return 0;
  32 }
  33
  34 static int query_topology_info(struct drm_i915_private *dev_priv,
  35                                struct drm_i915_query_item *query_item)
  36 {
  37         const struct sseu_dev_info *sseu = &RUNTIME_INFO(dev_priv)->sseu;
  38         struct drm_i915_query_topology_info topo;
  39         u32 slice_length, subslice_length, eu_length, total_length;
  40         u8 subslice_stride = GEN_SSEU_STRIDE(sseu->max_subslices);
  41         u8 eu_stride = GEN_SSEU_STRIDE(sseu->max_eus_per_subslice);
  42         int ret;
  43
  44         if (query_item->flags != 0)
  45                 return -EINVAL;
  46
  47         if (sseu->max_slices == 0)
  48                 return -ENODEV;
  49
  50         BUILD_BUG_ON(sizeof(u8) != sizeof(sseu->slice_mask));
  51
  52         slice_length = sizeof(sseu->slice_mask);
  53         subslice_length = sseu->max_slices * subslice_stride;
  54         eu_length = sseu->max_slices * sseu->max_subslices * eu_stride;
  55         total_length = sizeof(topo) + slice_length + subslice_length +
  56                        eu_length;
  57
  58         ret = copy_query_item(&topo, sizeof(topo), total_length,
  59                               query_item);
  60         if (ret != 0)
  61                 return ret;
  62
  63         if (topo.flags != 0)
  64                 return -EINVAL;
  65
  66         memset(&topo, 0, sizeof(topo));
  67         topo.max_slices = sseu->max_slices;
  68         topo.max_subslices = sseu->max_subslices;
  69         topo.max_eus_per_subslice = sseu->max_eus_per_subslice;
  70
  71         topo.subslice_offset = slice_length;
  72         topo.subslice_stride = subslice_stride;
  73         topo.eu_offset = slice_length + subslice_length;
  74         topo.eu_stride = eu_stride;
  75
  76         if (__copy_to_user(u64_to_user_ptr(query_item->data_ptr),
  77                            &topo, sizeof(topo)))
  78                 return -EFAULT;
  79
  80         if (__copy_to_user(u64_to_user_ptr(query_item->data_ptr + sizeof(topo)),
  81                            &sseu->slice_mask, slice_length))
  82                 return -EFAULT;
  83
  84         if (__copy_to_user(u64_to_user_ptr(query_item->data_ptr +
  85                                            sizeof(topo) + slice_length),
  86                            sseu->subslice_mask, subslice_length))
  87                 return -EFAULT;
  88
  89         if (__copy_to_user(u64_to_user_ptr(query_item->data_ptr +
  90                                            sizeof(topo) +
  91                                            slice_length + subslice_length),
  92                            sseu->eu_mask, eu_length))
  93                 return -EFAULT;
  94
  95         return total_length;
  96 }
  97
  98 static int
  99 query_engine_info(struct drm_i915_private *i915,
 100                   struct drm_i915_query_item *query_item)
 101 {
 102         struct drm_i915_query_engine_info __user *query_ptr =
 103                                 u64_to_user_ptr(query_item->data_ptr);
 104         struct drm_i915_engine_info __user *info_ptr;
 105         struct drm_i915_query_engine_info query;
 106         struct drm_i915_engine_info info = { };
 107         struct intel_engine_cs *engine;
 108         int len, ret;
 109
 110         if (query_item->flags)
 111                 return -EINVAL;
 112
 113         len = sizeof(struct drm_i915_query_engine_info) +
 114               RUNTIME_INFO(i915)->num_engines *
 115               sizeof(struct drm_i915_engine_info);
 116
 117         ret = copy_query_item(&query, sizeof(query), len, query_item);
 118         if (ret != 0)
 119                 return ret;
 120
 121         if (query.num_engines || query.rsvd[0] || query.rsvd[1] ||
 122             query.rsvd[2])
 123                 return -EINVAL;
 124
 125         info_ptr = &query_ptr->engines[0];
 126
 127         for_each_uabi_engine(engine, i915) {
 128                 info.engine.engine_class = engine->uabi_class;
 129                 info.engine.engine_instance = engine->uabi_instance;
 130                 info.capabilities = engine->uabi_capabilities;
 131
 132                 if (__copy_to_user(info_ptr, &info, sizeof(info)))
 133                         return -EFAULT;
 134
 135                 query.num_engines++;
 136                 info_ptr++;
 137         }
 138
 139         if (__copy_to_user(query_ptr, &query, sizeof(query)))
 140                 return -EFAULT;
 141
 142         return len;
 143 }
 144
 145 static int (* const i915_query_funcs[])(struct drm_i915_private *dev_priv,
 146                                         struct drm_i915_query_item *query_item) = {
 147         query_topology_info,
 148         query_engine_info,
 149 };
 150
 151 int i915_query_ioctl(struct drm_device *dev, void *data, struct drm_file *file)
 152 {
 153         struct drm_i915_private *dev_priv = to_i915(dev);
 154         struct drm_i915_query *args = data;
 155         struct drm_i915_query_item __user *user_item_ptr =
 156                 u64_to_user_ptr(args->items_ptr);
 157         u32 i;
 158
 159         if (args->flags != 0)
 160                 return -EINVAL;
 161
 162         for (i = 0; i < args->num_items; i++, user_item_ptr++) {
 163                 struct drm_i915_query_item item;
 164                 unsigned long func_idx;
 165                 int ret;
 166
 167                 if (copy_from_user(&item, user_item_ptr, sizeof(item)))
 168                         return -EFAULT;
 169
 170                 if (item.query_id == 0)
 171                         return -EINVAL;
 172
 173                 if (overflows_type(item.query_id - 1, unsigned long))
 174                         return -EINVAL;
 175
 176                 func_idx = item.query_id - 1;
 177
 178                 ret = -EINVAL;
 179                 if (func_idx < ARRAY_SIZE(i915_query_funcs)) {
 180                         func_idx = array_index_nospec(func_idx,
 181                                                       ARRAY_SIZE(i915_query_funcs));
 182                         ret = i915_query_funcs[func_idx](dev_priv, &item);
 183                 }
 184
 185                 /* Only write the length back to userspace if they differ. */
 186                 if (ret != item.length && put_user(ret, &user_item_ptr->length))
 187                         return -EFAULT;
 188         }
 189
 190         return 0;
 191 }