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/mm.h>
  31
  32 #include <drm/ttm/ttm_bo.h>
  33 #include <drm/ttm/ttm_device.h>
  34 #include <drm/ttm/ttm_tt.h>
  35 #include <drm/ttm/ttm_placement.h>
  36
  37 #include "ttm_module.h"
  38
  39 /*
  40  * ttm_global_mutex - protecting the global state
  41  */
  42 static DEFINE_MUTEX(ttm_global_mutex);
  43 static unsigned ttm_glob_use_count;
  44 struct ttm_global ttm_glob;
  45 EXPORT_SYMBOL(ttm_glob);
  46
  47 struct dentry *ttm_debugfs_root;
  48
  49 static void ttm_global_release(void)
  50 {
  51         struct ttm_global *glob = &ttm_glob;
  52
  53         mutex_lock(&ttm_global_mutex);
  54         if (--ttm_glob_use_count > 0)
  55                 goto out;
  56
  57         ttm_pool_mgr_fini();
  58         debugfs_remove(ttm_debugfs_root);
  59
  60         __free_page(glob->dummy_read_page);
  61         memset(glob, 0, sizeof(*glob));
  62 out:
  63         mutex_unlock(&ttm_global_mutex);
  64 }
  65
  66 static int ttm_global_init(void)
  67 {
  68         struct ttm_global *glob = &ttm_glob;
  69         unsigned long num_pages, num_dma32;
  70         struct sysinfo si;
  71         int ret = 0;
  72
  73         mutex_lock(&ttm_global_mutex);
  74         if (++ttm_glob_use_count > 1)
  75                 goto out;
  76
  77         si_meminfo(&si);
  78
  79         ttm_debugfs_root = debugfs_create_dir("ttm", NULL);
  80         if (IS_ERR(ttm_debugfs_root)) {
  81                 ttm_debugfs_root = NULL;
  82         }
  83
  84         /* Limit the number of pages in the pool to about 50% of the total
  85          * system memory.
  86          */
  87         num_pages = ((u64)si.totalram * si.mem_unit) >> PAGE_SHIFT;
  88         num_pages /= 2;
  89
  90         /* But for DMA32 we limit ourself to only use 2GiB maximum. */
  91         num_dma32 = (u64)(si.totalram - si.totalhigh) * si.mem_unit
  92                 >> PAGE_SHIFT;
  93         num_dma32 = min(num_dma32, 2UL << (30 - PAGE_SHIFT));
  94
  95         ttm_pool_mgr_init(num_pages);
  96         ttm_tt_mgr_init(num_pages, num_dma32);
  97
  98         glob->dummy_read_page = alloc_page(__GFP_ZERO | GFP_DMA32);
  99
 100         if (unlikely(glob->dummy_read_page == NULL)) {
 101                 ret = -ENOMEM;
 102                 goto out;
 103         }
 104
 105         INIT_LIST_HEAD(&glob->device_list);
 106         atomic_set(&glob->bo_count, 0);
 107
 108         debugfs_create_atomic_t("buffer_objects", 0444, ttm_debugfs_root,
 109                                 &glob->bo_count);
 110 out:
 111         if (ret && ttm_debugfs_root)
 112                 debugfs_remove(ttm_debugfs_root);
 113         if (ret)
 114                 --ttm_glob_use_count;
 115         mutex_unlock(&ttm_global_mutex);
 116         return ret;
 117 }
 118
 119 /*
 120  * A buffer object shrink method that tries to swap out the first
 121  * buffer object on the global::swap_lru list.
 122  */
 123 int ttm_global_swapout(struct ttm_operation_ctx *ctx, gfp_t gfp_flags)
 124 {
 125         struct ttm_global *glob = &ttm_glob;
 126         struct ttm_device *bdev;
 127         int ret = 0;
 128
 129         mutex_lock(&ttm_global_mutex);
 130         list_for_each_entry(bdev, &glob->device_list, device_list) {
 131                 ret = ttm_device_swapout(bdev, ctx, gfp_flags);
 132                 if (ret > 0) {
 133                         list_move_tail(&bdev->device_list, &glob->device_list);
 134                         break;
 135                 }
 136         }
 137         mutex_unlock(&ttm_global_mutex);
 138         return ret;
 139 }
 140
 141 int ttm_device_swapout(struct ttm_device *bdev, struct ttm_operation_ctx *ctx,
 142                        gfp_t gfp_flags)
 143 {
 144         struct ttm_resource_cursor cursor;
 145         struct ttm_resource_manager *man;
 146         struct ttm_resource *res;
 147         unsigned i;
 148         int ret;
 149
 150         spin_lock(&bdev->lru_lock);
 151         for (i = TTM_PL_SYSTEM; i < TTM_NUM_MEM_TYPES; ++i) {
 152                 man = ttm_manager_type(bdev, i);
 153                 if (!man || !man->use_tt)
 154                         continue;
 155
 156                 ttm_resource_manager_for_each_res(man, &cursor, res) {
 157                         struct ttm_buffer_object *bo = res->bo;
 158                         uint32_t num_pages;
 159
 160                         if (!bo)
 161                                 continue;
 162
 163                         num_pages = PFN_UP(bo->base.size);
 164                         ret = ttm_bo_swapout(bo, ctx, gfp_flags);
 165                         /* ttm_bo_swapout has dropped the lru_lock */
 166                         if (!ret)
 167                                 return num_pages;
 168                         if (ret != -EBUSY)
 169                                 return ret;
 170                 }
 171         }
 172         spin_unlock(&bdev->lru_lock);
 173         return 0;
 174 }
 175 EXPORT_SYMBOL(ttm_device_swapout);
 176
 177 /**
 178  * ttm_device_init
 179  *
 180  * @bdev: A pointer to a struct ttm_device to initialize.
 181  * @funcs: Function table for the device.
 182  * @dev: The core kernel device pointer for DMA mappings and allocations.
 183  * @mapping: The address space to use for this bo.
 184  * @vma_manager: A pointer to a vma manager.
 185  * @use_dma_alloc: If coherent DMA allocation API should be used.
 186  * @use_dma32: If we should use GFP_DMA32 for device memory allocations.
 187  *
 188  * Initializes a struct ttm_device:
 189  * Returns:
 190  * !0: Failure.
 191  */
 192 int ttm_device_init(struct ttm_device *bdev, struct ttm_device_funcs *funcs,
 193                     struct device *dev, struct address_space *mapping,
 194                     struct drm_vma_offset_manager *vma_manager,
 195                     bool use_dma_alloc, bool use_dma32)
 196 {
 197         struct ttm_global *glob = &ttm_glob;
 198         int ret;
 199
 200         if (WARN_ON(vma_manager == NULL))
 201                 return -EINVAL;
 202
 203         ret = ttm_global_init();
 204         if (ret)
 205                 return ret;
 206
 207         bdev->wq = alloc_workqueue("ttm", WQ_MEM_RECLAIM | WQ_HIGHPRI, 16);
 208         if (!bdev->wq) {
 209                 ttm_global_release();
 210                 return -ENOMEM;
 211         }
 212
 213         bdev->funcs = funcs;
 214
 215         ttm_sys_man_init(bdev);
 216         ttm_pool_init(&bdev->pool, dev, use_dma_alloc, use_dma32);
 217
 218         bdev->vma_manager = vma_manager;
 219         spin_lock_init(&bdev->lru_lock);
 220         INIT_LIST_HEAD(&bdev->pinned);
 221         bdev->dev_mapping = mapping;
 222         mutex_lock(&ttm_global_mutex);
 223         list_add_tail(&bdev->device_list, &glob->device_list);
 224         mutex_unlock(&ttm_global_mutex);
 225
 226         return 0;
 227 }
 228 EXPORT_SYMBOL(ttm_device_init);
 229
 230 void ttm_device_fini(struct ttm_device *bdev)
 231 {
 232         struct ttm_resource_manager *man;
 233         unsigned i;
 234
 235         man = ttm_manager_type(bdev, TTM_PL_SYSTEM);
 236         ttm_resource_manager_set_used(man, false);
 237         ttm_set_driver_manager(bdev, TTM_PL_SYSTEM, NULL);
 238
 239         mutex_lock(&ttm_global_mutex);
 240         list_del(&bdev->device_list);
 241         mutex_unlock(&ttm_global_mutex);
 242
 243         drain_workqueue(bdev->wq);
 244         destroy_workqueue(bdev->wq);
 245
 246         spin_lock(&bdev->lru_lock);
 247         for (i = 0; i < TTM_MAX_BO_PRIORITY; ++i)
 248                 if (list_empty(&man->lru[0]))
 249                         pr_debug("Swap list %d was clean\n", i);
 250         spin_unlock(&bdev->lru_lock);
 251
 252         ttm_pool_fini(&bdev->pool);
 253         ttm_global_release();
 254 }
 255 EXPORT_SYMBOL(ttm_device_fini);
 256
 257 static void ttm_device_clear_lru_dma_mappings(struct ttm_device *bdev,
 258                                               struct list_head *list)
 259 {
 260         struct ttm_resource *res;
 261
 262         spin_lock(&bdev->lru_lock);
 263         while ((res = list_first_entry_or_null(list, typeof(*res), lru))) {
 264                 struct ttm_buffer_object *bo = res->bo;
 265
 266                 /* Take ref against racing releases once lru_lock is unlocked */
 267                 if (!ttm_bo_get_unless_zero(bo))
 268                         continue;
 269
 270                 list_del_init(&res->lru);
 271                 spin_unlock(&bdev->lru_lock);
 272
 273                 if (bo->ttm)
 274                         ttm_tt_unpopulate(bo->bdev, bo->ttm);
 275
 276                 ttm_bo_put(bo);
 277                 spin_lock(&bdev->lru_lock);
 278         }
 279         spin_unlock(&bdev->lru_lock);
 280 }
 281
 282 void ttm_device_clear_dma_mappings(struct ttm_device *bdev)
 283 {
 284         struct ttm_resource_manager *man;
 285         unsigned int i, j;
 286
 287         ttm_device_clear_lru_dma_mappings(bdev, &bdev->pinned);
 288
 289         for (i = TTM_PL_SYSTEM; i < TTM_NUM_MEM_TYPES; ++i) {
 290                 man = ttm_manager_type(bdev, i);
 291                 if (!man || !man->use_tt)
 292                         continue;
 293
 294                 for (j = 0; j < TTM_MAX_BO_PRIORITY; ++j)
 295                         ttm_device_clear_lru_dma_mappings(bdev, &man->lru[j]);
 296         }
 297 }
 298 EXPORT_SYMBOL(ttm_device_clear_dma_mappings);