drivers/gpu/drm/ttm/ttm_device.c

   1 /* SPDX-License-Identifier: GPL-2.0 OR MIT */
   2
   3 /*
   4  * Copyright (c) 2006-2009 VMware, Inc., Palo Alto, CA., USA
   5  * Copyright 2020 Advanced Micro Devices, Inc.
   6  *
   7  * Permission is hereby granted, free of charge, to any person obtaining a
   8  * copy of this software and associated documentation files (the "Software"),
   9  * to deal in the Software without restriction, including without limitation
  10  * the rights to use, copy, modify, merge, publish, distribute, sublicense,
  11  * and/or sell copies of the Software, and to permit persons to whom the
  12  * Software is furnished to do so, subject to the following conditions:
  13  *
  14  * The above copyright notice and this permission notice shall be included in
  15  * all copies or substantial portions of the Software.
  16  *
  17  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
  18  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  19  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
  20  * THE COPYRIGHT HOLDER(S) OR AUTHOR(S) BE LIABLE FOR ANY CLAIM, DAMAGES OR
  21  * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
  22  * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
  23  * OTHER DEALINGS IN THE SOFTWARE.
  24  *
  25  * Authors: Christian König
  26  */
  27
  28 #define pr_fmt(fmt) "[TTM DEVICE] " fmt
  29
  30 #include <linux/debugfs.h>
  31 #include <linux/mm.h>
  32
  33 #include <drm/ttm/ttm_bo.h>
  34 #include <drm/ttm/ttm_device.h>
  35 #include <drm/ttm/ttm_tt.h>
  36 #include <drm/ttm/ttm_placement.h>
  37
  38 #include "ttm_module.h"
  39
  40 /*
  41  * ttm_global_mutex - protecting the global state
  42  */
  43 static DEFINE_MUTEX(ttm_global_mutex);
  44 static unsigned ttm_glob_use_count;
  45 struct ttm_global ttm_glob;
  46 EXPORT_SYMBOL(ttm_glob);
  47
  48 struct dentry *ttm_debugfs_root;
  49
  50 static void ttm_global_release(void)
  51 {
  52         struct ttm_global *glob = &ttm_glob;
  53
  54         mutex_lock(&ttm_global_mutex);
  55         if (--ttm_glob_use_count > 0)
  56                 goto out;
  57
  58         ttm_pool_mgr_fini();
  59         debugfs_remove(ttm_debugfs_root);
  60
  61         __free_page(glob->dummy_read_page);
  62         memset(glob, 0, sizeof(*glob));
  63 out:
  64         mutex_unlock(&ttm_global_mutex);
  65 }
  66
  67 static int ttm_global_init(void)
  68 {
  69         struct ttm_global *glob = &ttm_glob;
  70         unsigned long num_pages, num_dma32;
  71         struct sysinfo si;
  72         int ret = 0;
  73
  74         mutex_lock(&ttm_global_mutex);
  75         if (++ttm_glob_use_count > 1)
  76                 goto out;
  77
  78         si_meminfo(&si);
  79
  80         ttm_debugfs_root = debugfs_create_dir("ttm", NULL);
  81         if (IS_ERR(ttm_debugfs_root)) {
  82                 ttm_debugfs_root = NULL;
  83         }
  84
  85         /* Limit the number of pages in the pool to about 50% of the total
  86          * system memory.
  87          */
  88         num_pages = ((u64)si.totalram * si.mem_unit) >> PAGE_SHIFT;
  89         num_pages /= 2;
  90
  91         /* But for DMA32 we limit ourself to only use 2GiB maximum. */
  92         num_dma32 = (u64)(si.totalram - si.totalhigh) * si.mem_unit
  93                 >> PAGE_SHIFT;
  94         num_dma32 = min(num_dma32, 2UL << (30 - PAGE_SHIFT));
  95
  96         ttm_pool_mgr_init(num_pages);
  97         ttm_tt_mgr_init(num_pages, num_dma32);
  98
  99         glob->dummy_read_page = alloc_page(__GFP_ZERO | GFP_DMA32 |
 100                                            __GFP_NOWARN);
 101
 102         /* Retry without GFP_DMA32 for platforms DMA32 is not available */
 103         if (unlikely(glob->dummy_read_page == NULL)) {
 104                 glob->dummy_read_page = alloc_page(__GFP_ZERO);
 105                 if (unlikely(glob->dummy_read_page == NULL)) {
 106                         ret = -ENOMEM;
 107                         goto out;
 108                 }
 109                 pr_warn("Using GFP_DMA32 fallback for dummy_read_page\n");
 110         }
 111
 112         INIT_LIST_HEAD(&glob->device_list);
 113         atomic_set(&glob->bo_count, 0);
 114
 115         debugfs_create_atomic_t("buffer_objects", 0444, ttm_debugfs_root,
 116                                 &glob->bo_count);
 117 out:
 118         if (ret && ttm_debugfs_root)
 119                 debugfs_remove(ttm_debugfs_root);
 120         if (ret)
 121                 --ttm_glob_use_count;
 122         mutex_unlock(&ttm_global_mutex);
 123         return ret;
 124 }
 125
 126 /*
 127  * A buffer object shrink method that tries to swap out the first
 128  * buffer object on the global::swap_lru list.
 129  */
 130 int ttm_global_swapout(struct ttm_operation_ctx *ctx, gfp_t gfp_flags)
 131 {
 132         struct ttm_global *glob = &ttm_glob;
 133         struct ttm_device *bdev;
 134         int ret = 0;
 135
 136         mutex_lock(&ttm_global_mutex);
 137         list_for_each_entry(bdev, &glob->device_list, device_list) {
 138                 ret = ttm_device_swapout(bdev, ctx, gfp_flags);
 139                 if (ret > 0) {
 140                         list_move_tail(&bdev->device_list, &glob->device_list);
 141                         break;
 142                 }
 143         }
 144         mutex_unlock(&ttm_global_mutex);
 145         return ret;
 146 }
 147
 148 int ttm_device_swapout(struct ttm_device *bdev, struct ttm_operation_ctx *ctx,
 149                        gfp_t gfp_flags)
 150 {
 151         struct ttm_resource_manager *man;
 152         unsigned i;
 153         s64 lret;
 154
 155         for (i = TTM_PL_SYSTEM; i < TTM_NUM_MEM_TYPES; ++i) {
 156                 man = ttm_manager_type(bdev, i);
 157                 if (!man || !man->use_tt)
 158                         continue;
 159
 160                 lret = ttm_bo_swapout(bdev, ctx, man, gfp_flags, 1);
 161                 /* Can be both positive (num_pages) and negative (error) */
 162                 if (lret)
 163                         return lret;
 164         }
 165         return 0;
 166 }
 167 EXPORT_SYMBOL(ttm_device_swapout);
 168
 169 /**
 170  * ttm_device_init
 171  *
 172  * @bdev: A pointer to a struct ttm_device to initialize.
 173  * @funcs: Function table for the device.
 174  * @dev: The core kernel device pointer for DMA mappings and allocations.
 175  * @mapping: The address space to use for this bo.
 176  * @vma_manager: A pointer to a vma manager.
 177  * @use_dma_alloc: If coherent DMA allocation API should be used.
 178  * @use_dma32: If we should use GFP_DMA32 for device memory allocations.
 179  *
 180  * Initializes a struct ttm_device:
 181  * Returns:
 182  * !0: Failure.
 183  */
 184 int ttm_device_init(struct ttm_device *bdev, const struct ttm_device_funcs *funcs,
 185                     struct device *dev, struct address_space *mapping,
 186                     struct drm_vma_offset_manager *vma_manager,
 187                     bool use_dma_alloc, bool use_dma32)
 188 {
 189         struct ttm_global *glob = &ttm_glob;
 190         int ret, nid;
 191
 192         if (WARN_ON(vma_manager == NULL))
 193                 return -EINVAL;
 194
 195         ret = ttm_global_init();
 196         if (ret)
 197                 return ret;
 198
 199         bdev->wq = alloc_workqueue("ttm",
 200                                    WQ_MEM_RECLAIM | WQ_HIGHPRI | WQ_UNBOUND, 16);
 201         if (!bdev->wq) {
 202                 ttm_global_release();
 203                 return -ENOMEM;
 204         }
 205
 206         bdev->funcs = funcs;
 207
 208         ttm_sys_man_init(bdev);
 209
 210         if (dev)
 211                 nid = dev_to_node(dev);
 212         else
 213                 nid = NUMA_NO_NODE;
 214
 215         ttm_pool_init(&bdev->pool, dev, nid, use_dma_alloc, use_dma32);
 216
 217         bdev->vma_manager = vma_manager;
 218         spin_lock_init(&bdev->lru_lock);
 219         INIT_LIST_HEAD(&bdev->unevictable);
 220         bdev->dev_mapping = mapping;
 221         mutex_lock(&ttm_global_mutex);
 222         list_add_tail(&bdev->device_list, &glob->device_list);
 223         mutex_unlock(&ttm_global_mutex);
 224
 225         return 0;
 226 }
 227 EXPORT_SYMBOL(ttm_device_init);
 228
 229 void ttm_device_fini(struct ttm_device *bdev)
 230 {
 231         struct ttm_resource_manager *man;
 232         unsigned i;
 233
 234         mutex_lock(&ttm_global_mutex);
 235         list_del(&bdev->device_list);
 236         mutex_unlock(&ttm_global_mutex);
 237
 238         drain_workqueue(bdev->wq);
 239         destroy_workqueue(bdev->wq);
 240
 241         man = ttm_manager_type(bdev, TTM_PL_SYSTEM);
 242         ttm_resource_manager_set_used(man, false);
 243         ttm_set_driver_manager(bdev, TTM_PL_SYSTEM, NULL);
 244
 245         spin_lock(&bdev->lru_lock);
 246         for (i = 0; i < TTM_MAX_BO_PRIORITY; ++i)
 247                 if (list_empty(&man->lru[0]))
 248                         pr_debug("Swap list %d was clean\n", i);
 249         spin_unlock(&bdev->lru_lock);
 250
 251         ttm_pool_fini(&bdev->pool);
 252         ttm_global_release();
 253 }
 254 EXPORT_SYMBOL(ttm_device_fini);
 255
 256 static void ttm_device_clear_lru_dma_mappings(struct ttm_device *bdev,
 257                                               struct list_head *list)
 258 {
 259         struct ttm_resource *res;
 260
 261         spin_lock(&bdev->lru_lock);
 262         while ((res = ttm_lru_first_res_or_null(list))) {
 263                 struct ttm_buffer_object *bo = res->bo;
 264
 265                 /* Take ref against racing releases once lru_lock is unlocked */
 266                 if (!ttm_bo_get_unless_zero(bo))
 267                         continue;
 268
 269                 list_del_init(&bo->resource->lru.link);
 270                 spin_unlock(&bdev->lru_lock);
 271
 272                 if (bo->ttm)
 273                         ttm_tt_unpopulate(bo->bdev, bo->ttm);
 274
 275                 ttm_bo_put(bo);
 276                 spin_lock(&bdev->lru_lock);
 277         }
 278         spin_unlock(&bdev->lru_lock);
 279 }
 280
 281 void ttm_device_clear_dma_mappings(struct ttm_device *bdev)
 282 {
 283         struct ttm_resource_manager *man;
 284         unsigned int i, j;
 285
 286         ttm_device_clear_lru_dma_mappings(bdev, &bdev->unevictable);
 287
 288         for (i = TTM_PL_SYSTEM; i < TTM_NUM_MEM_TYPES; ++i) {
 289                 man = ttm_manager_type(bdev, i);
 290                 if (!man || !man->use_tt)
 291                         continue;
 292
 293                 for (j = 0; j < TTM_MAX_BO_PRIORITY; ++j)
 294                         ttm_device_clear_lru_dma_mappings(bdev, &man->lru[j]);
 295         }
 296 }
 297 EXPORT_SYMBOL(ttm_device_clear_dma_mappings);