drivers/gpu/drm/vmwgfx/vmwgfx_mob.c

   1 // SPDX-License-Identifier: GPL-2.0 OR MIT
   2 /**************************************************************************
   3  *
   4  * Copyright 2012-2023 VMware, Inc., Palo Alto, CA., USA
   5  *
   6  * Permission is hereby granted, free of charge, to any person obtaining a
   7  * copy of this software and associated documentation files (the
   8  * "Software"), to deal in the Software without restriction, including
   9  * without limitation the rights to use, copy, modify, merge, publish,
  10  * distribute, sub license, and/or sell copies of the Software, and to
  11  * permit persons to whom the Software is furnished to do so, subject to
  12  * the following conditions:
  13  *
  14  * The above copyright notice and this permission notice (including the
  15  * next paragraph) shall be included in all copies or substantial portions
  16  * of the Software.
  17  *
  18  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
  19  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  20  * FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT. IN NO EVENT SHALL
  21  * THE COPYRIGHT HOLDERS, AUTHORS AND/OR ITS SUPPLIERS BE LIABLE FOR ANY CLAIM,
  22  * DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR
  23  * OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE
  24  * USE OR OTHER DEALINGS IN THE SOFTWARE.
  25  *
  26  **************************************************************************/
  27
  28 #include "vmwgfx_bo.h"
  29 #include "vmwgfx_drv.h"
  30
  31 #include <linux/highmem.h>
  32
  33 #ifdef CONFIG_64BIT
  34 #define VMW_PPN_SIZE 8
  35 #define VMW_MOBFMT_PTDEPTH_0 SVGA3D_MOBFMT_PT64_0
  36 #define VMW_MOBFMT_PTDEPTH_1 SVGA3D_MOBFMT_PT64_1
  37 #define VMW_MOBFMT_PTDEPTH_2 SVGA3D_MOBFMT_PT64_2
  38 #else
  39 #define VMW_PPN_SIZE 4
  40 #define VMW_MOBFMT_PTDEPTH_0 SVGA3D_MOBFMT_PT_0
  41 #define VMW_MOBFMT_PTDEPTH_1 SVGA3D_MOBFMT_PT_1
  42 #define VMW_MOBFMT_PTDEPTH_2 SVGA3D_MOBFMT_PT_2
  43 #endif
  44
  45 /*
  46  * struct vmw_mob - Structure containing page table and metadata for a
  47  * Guest Memory OBject.
  48  *
  49  * @num_pages       Number of pages that make up the page table.
  50  * @pt_level        The indirection level of the page table. 0-2.
  51  * @pt_root_page    DMA address of the level 0 page of the page table.
  52  */
  53 struct vmw_mob {
  54         struct ttm_buffer_object *pt_bo;
  55         unsigned long num_pages;
  56         unsigned pt_level;
  57         dma_addr_t pt_root_page;
  58         uint32_t id;
  59 };
  60
  61 /*
  62  * struct vmw_otable - Guest Memory OBject table metadata
  63  *
  64  * @size:           Size of the table (page-aligned).
  65  * @page_table:     Pointer to a struct vmw_mob holding the page table.
  66  */
  67 static const struct vmw_otable pre_dx_tables[] = {
  68         {VMWGFX_NUM_MOB * sizeof(SVGAOTableMobEntry), NULL, true},
  69         {VMWGFX_NUM_GB_SURFACE * sizeof(SVGAOTableSurfaceEntry), NULL, true},
  70         {VMWGFX_NUM_GB_CONTEXT * sizeof(SVGAOTableContextEntry), NULL, true},
  71         {VMWGFX_NUM_GB_SHADER * sizeof(SVGAOTableShaderEntry), NULL, true},
  72         {VMWGFX_NUM_GB_SCREEN_TARGET * sizeof(SVGAOTableScreenTargetEntry),
  73          NULL, true}
  74 };
  75
  76 static const struct vmw_otable dx_tables[] = {
  77         {VMWGFX_NUM_MOB * sizeof(SVGAOTableMobEntry), NULL, true},
  78         {VMWGFX_NUM_GB_SURFACE * sizeof(SVGAOTableSurfaceEntry), NULL, true},
  79         {VMWGFX_NUM_GB_CONTEXT * sizeof(SVGAOTableContextEntry), NULL, true},
  80         {VMWGFX_NUM_GB_SHADER * sizeof(SVGAOTableShaderEntry), NULL, true},
  81         {VMWGFX_NUM_GB_SCREEN_TARGET * sizeof(SVGAOTableScreenTargetEntry),
  82          NULL, true},
  83         {VMWGFX_NUM_DXCONTEXT * sizeof(SVGAOTableDXContextEntry), NULL, true},
  84 };
  85
  86 static int vmw_mob_pt_populate(struct vmw_private *dev_priv,
  87                                struct vmw_mob *mob);
  88 static void vmw_mob_pt_setup(struct vmw_mob *mob,
  89                              struct vmw_piter data_iter,
  90                              unsigned long num_data_pages);
  91
  92
  93 static inline void vmw_bo_unpin_unlocked(struct ttm_buffer_object *bo)
  94 {
  95         int ret = ttm_bo_reserve(bo, false, true, NULL);
  96         BUG_ON(ret != 0);
  97         ttm_bo_unpin(bo);
  98         ttm_bo_unreserve(bo);
  99 }
 100
 101
 102 /*
 103  * vmw_setup_otable_base - Issue an object table base setup command to
 104  * the device
 105  *
 106  * @dev_priv:       Pointer to a device private structure
 107  * @type:           Type of object table base
 108  * @offset          Start of table offset into dev_priv::otable_bo
 109  * @otable          Pointer to otable metadata;
 110  *
 111  * This function returns -ENOMEM if it fails to reserve fifo space,
 112  * and may block waiting for fifo space.
 113  */
 114 static int vmw_setup_otable_base(struct vmw_private *dev_priv,
 115                                  SVGAOTableType type,
 116                                  struct ttm_buffer_object *otable_bo,
 117                                  unsigned long offset,
 118                                  struct vmw_otable *otable)
 119 {
 120         struct {
 121                 SVGA3dCmdHeader header;
 122                 SVGA3dCmdSetOTableBase64 body;
 123         } *cmd;
 124         struct vmw_mob *mob;
 125         const struct vmw_sg_table *vsgt;
 126         struct vmw_piter iter;
 127         int ret;
 128
 129         BUG_ON(otable->page_table != NULL);
 130
 131         vsgt = vmw_bo_sg_table(otable_bo);
 132         vmw_piter_start(&iter, vsgt, offset >> PAGE_SHIFT);
 133         WARN_ON(!vmw_piter_next(&iter));
 134
 135         mob = vmw_mob_create(otable->size >> PAGE_SHIFT);
 136         if (unlikely(mob == NULL)) {
 137                 DRM_ERROR("Failed creating OTable page table.\n");
 138                 return -ENOMEM;
 139         }
 140
 141         if (otable->size <= PAGE_SIZE) {
 142                 mob->pt_level = VMW_MOBFMT_PTDEPTH_0;
 143                 mob->pt_root_page = vmw_piter_dma_addr(&iter);
 144         } else {
 145                 ret = vmw_mob_pt_populate(dev_priv, mob);
 146                 if (unlikely(ret != 0))
 147                         goto out_no_populate;
 148
 149                 vmw_mob_pt_setup(mob, iter, otable->size >> PAGE_SHIFT);
 150                 mob->pt_level += VMW_MOBFMT_PTDEPTH_1 - SVGA3D_MOBFMT_PT_1;
 151         }
 152
 153         cmd = VMW_CMD_RESERVE(dev_priv, sizeof(*cmd));
 154         if (unlikely(cmd == NULL)) {
 155                 ret = -ENOMEM;
 156                 goto out_no_fifo;
 157         }
 158
 159         memset(cmd, 0, sizeof(*cmd));
 160         cmd->header.id = SVGA_3D_CMD_SET_OTABLE_BASE64;
 161         cmd->header.size = sizeof(cmd->body);
 162         cmd->body.type = type;
 163         cmd->body.baseAddress = mob->pt_root_page >> PAGE_SHIFT;
 164         cmd->body.sizeInBytes = otable->size;
 165         cmd->body.validSizeInBytes = 0;
 166         cmd->body.ptDepth = mob->pt_level;
 167
 168         /*
 169          * The device doesn't support this, But the otable size is
 170          * determined at compile-time, so this BUG shouldn't trigger
 171          * randomly.
 172          */
 173         BUG_ON(mob->pt_level == VMW_MOBFMT_PTDEPTH_2);
 174
 175         vmw_cmd_commit(dev_priv, sizeof(*cmd));
 176         otable->page_table = mob;
 177
 178         return 0;
 179
 180 out_no_fifo:
 181 out_no_populate:
 182         vmw_mob_destroy(mob);
 183         return ret;
 184 }
 185
 186 /*
 187  * vmw_takedown_otable_base - Issue an object table base takedown command
 188  * to the device
 189  *
 190  * @dev_priv:       Pointer to a device private structure
 191  * @type:           Type of object table base
 192  *
 193  */
 194 static void vmw_takedown_otable_base(struct vmw_private *dev_priv,
 195                                      SVGAOTableType type,
 196                                      struct vmw_otable *otable)
 197 {
 198         struct {
 199                 SVGA3dCmdHeader header;
 200                 SVGA3dCmdSetOTableBase body;
 201         } *cmd;
 202         struct ttm_buffer_object *bo;
 203
 204         if (otable->page_table == NULL)
 205                 return;
 206
 207         bo = otable->page_table->pt_bo;
 208         cmd = VMW_CMD_RESERVE(dev_priv, sizeof(*cmd));
 209         if (unlikely(cmd == NULL))
 210                 return;
 211
 212         memset(cmd, 0, sizeof(*cmd));
 213         cmd->header.id = SVGA_3D_CMD_SET_OTABLE_BASE;
 214         cmd->header.size = sizeof(cmd->body);
 215         cmd->body.type = type;
 216         cmd->body.baseAddress = 0;
 217         cmd->body.sizeInBytes = 0;
 218         cmd->body.validSizeInBytes = 0;
 219         cmd->body.ptDepth = SVGA3D_MOBFMT_INVALID;
 220         vmw_cmd_commit(dev_priv, sizeof(*cmd));
 221
 222         if (bo) {
 223                 int ret;
 224
 225                 ret = ttm_bo_reserve(bo, false, true, NULL);
 226                 BUG_ON(ret != 0);
 227
 228                 vmw_bo_fence_single(bo, NULL);
 229                 ttm_bo_unreserve(bo);
 230         }
 231
 232         vmw_mob_destroy(otable->page_table);
 233         otable->page_table = NULL;
 234 }
 235
 236
 237 static int vmw_otable_batch_setup(struct vmw_private *dev_priv,
 238                                   struct vmw_otable_batch *batch)
 239 {
 240         unsigned long offset;
 241         unsigned long bo_size;
 242         struct vmw_otable *otables = batch->otables;
 243         SVGAOTableType i;
 244         int ret;
 245
 246         bo_size = 0;
 247         for (i = 0; i < batch->num_otables; ++i) {
 248                 if (!otables[i].enabled)
 249                         continue;
 250
 251                 otables[i].size = PFN_ALIGN(otables[i].size);
 252                 bo_size += otables[i].size;
 253         }
 254
 255         ret = vmw_bo_create_and_populate(dev_priv, bo_size, &batch->otable_bo);
 256         if (unlikely(ret != 0))
 257                 return ret;
 258
 259         offset = 0;
 260         for (i = 0; i < batch->num_otables; ++i) {
 261                 if (!batch->otables[i].enabled)
 262                         continue;
 263
 264                 ret = vmw_setup_otable_base(dev_priv, i, batch->otable_bo,
 265                                             offset,
 266                                             &otables[i]);
 267                 if (unlikely(ret != 0))
 268                         goto out_no_setup;
 269                 offset += otables[i].size;
 270         }
 271
 272         return 0;
 273
 274 out_no_setup:
 275         for (i = 0; i < batch->num_otables; ++i) {
 276                 if (batch->otables[i].enabled)
 277                         vmw_takedown_otable_base(dev_priv, i,
 278                                                  &batch->otables[i]);
 279         }
 280
 281         vmw_bo_unpin_unlocked(batch->otable_bo);
 282         ttm_bo_put(batch->otable_bo);
 283         batch->otable_bo = NULL;
 284         return ret;
 285 }
 286
 287 /*
 288  * vmw_otables_setup - Set up guest backed memory object tables
 289  *
 290  * @dev_priv:       Pointer to a device private structure
 291  *
 292  * Takes care of the device guest backed surface
 293  * initialization, by setting up the guest backed memory object tables.
 294  * Returns 0 on success and various error codes on failure. A successful return
 295  * means the object tables can be taken down using the vmw_otables_takedown
 296  * function.
 297  */
 298 int vmw_otables_setup(struct vmw_private *dev_priv)
 299 {
 300         struct vmw_otable **otables = &dev_priv->otable_batch.otables;
 301         int ret;
 302
 303         if (has_sm4_context(dev_priv)) {
 304                 *otables = kmemdup(dx_tables, sizeof(dx_tables), GFP_KERNEL);
 305                 if (!(*otables))
 306                         return -ENOMEM;
 307
 308                 dev_priv->otable_batch.num_otables = ARRAY_SIZE(dx_tables);
 309         } else {
 310                 *otables = kmemdup(pre_dx_tables, sizeof(pre_dx_tables),
 311                                    GFP_KERNEL);
 312                 if (!(*otables))
 313                         return -ENOMEM;
 314
 315                 dev_priv->otable_batch.num_otables = ARRAY_SIZE(pre_dx_tables);
 316         }
 317
 318         ret = vmw_otable_batch_setup(dev_priv, &dev_priv->otable_batch);
 319         if (unlikely(ret != 0))
 320                 goto out_setup;
 321
 322         return 0;
 323
 324 out_setup:
 325         kfree(*otables);
 326         return ret;
 327 }
 328
 329 static void vmw_otable_batch_takedown(struct vmw_private *dev_priv,
 330                                struct vmw_otable_batch *batch)
 331 {
 332         SVGAOTableType i;
 333         struct ttm_buffer_object *bo = batch->otable_bo;
 334         int ret;
 335
 336         for (i = 0; i < batch->num_otables; ++i)
 337                 if (batch->otables[i].enabled)
 338                         vmw_takedown_otable_base(dev_priv, i,
 339                                                  &batch->otables[i]);
 340
 341         ret = ttm_bo_reserve(bo, false, true, NULL);
 342         BUG_ON(ret != 0);
 343
 344         vmw_bo_fence_single(bo, NULL);
 345         ttm_bo_unpin(bo);
 346         ttm_bo_unreserve(bo);
 347
 348         ttm_bo_put(batch->otable_bo);
 349         batch->otable_bo = NULL;
 350 }
 351
 352 /*
 353  * vmw_otables_takedown - Take down guest backed memory object tables
 354  *
 355  * @dev_priv:       Pointer to a device private structure
 356  *
 357  * Take down the Guest Memory Object tables.
 358  */
 359 void vmw_otables_takedown(struct vmw_private *dev_priv)
 360 {
 361         vmw_otable_batch_takedown(dev_priv, &dev_priv->otable_batch);
 362         kfree(dev_priv->otable_batch.otables);
 363 }
 364
 365 /*
 366  * vmw_mob_calculate_pt_pages - Calculate the number of page table pages
 367  * needed for a guest backed memory object.
 368  *
 369  * @data_pages:  Number of data pages in the memory object buffer.
 370  */
 371 static unsigned long vmw_mob_calculate_pt_pages(unsigned long data_pages)
 372 {
 373         unsigned long data_size = data_pages * PAGE_SIZE;
 374         unsigned long tot_size = 0;
 375
 376         while (likely(data_size > PAGE_SIZE)) {
 377                 data_size = DIV_ROUND_UP(data_size, PAGE_SIZE);
 378                 data_size *= VMW_PPN_SIZE;
 379                 tot_size += PFN_ALIGN(data_size);
 380         }
 381
 382         return tot_size >> PAGE_SHIFT;
 383 }
 384
 385 /*
 386  * vmw_mob_create - Create a mob, but don't populate it.
 387  *
 388  * @data_pages:  Number of data pages of the underlying buffer object.
 389  */
 390 struct vmw_mob *vmw_mob_create(unsigned long data_pages)
 391 {
 392         struct vmw_mob *mob = kzalloc(sizeof(*mob), GFP_KERNEL);
 393
 394         if (unlikely(!mob))
 395                 return NULL;
 396
 397         mob->num_pages = vmw_mob_calculate_pt_pages(data_pages);
 398
 399         return mob;
 400 }
 401
 402 /*
 403  * vmw_mob_pt_populate - Populate the mob pagetable
 404  *
 405  * @mob:         Pointer to the mob the pagetable of which we want to
 406  *               populate.
 407  *
 408  * This function allocates memory to be used for the pagetable.
 409  * Returns ENOMEM if memory resources aren't sufficient and may
 410  * cause TTM buffer objects to be swapped out.
 411  */
 412 static int vmw_mob_pt_populate(struct vmw_private *dev_priv,
 413                                struct vmw_mob *mob)
 414 {
 415         BUG_ON(mob->pt_bo != NULL);
 416
 417         return vmw_bo_create_and_populate(dev_priv, mob->num_pages * PAGE_SIZE, &mob->pt_bo);
 418 }
 419
 420 /**
 421  * vmw_mob_assign_ppn - Assign a value to a page table entry
 422  *
 423  * @addr: Pointer to pointer to page table entry.
 424  * @val: The page table entry
 425  *
 426  * Assigns a value to a page table entry pointed to by *@addr and increments
 427  * *@addr according to the page table entry size.
 428  */
 429 #if (VMW_PPN_SIZE == 8)
 430 static void vmw_mob_assign_ppn(u32 **addr, dma_addr_t val)
 431 {
 432         *((u64 *) *addr) = val >> PAGE_SHIFT;
 433         *addr += 2;
 434 }
 435 #else
 436 static void vmw_mob_assign_ppn(u32 **addr, dma_addr_t val)
 437 {
 438         *(*addr)++ = val >> PAGE_SHIFT;
 439 }
 440 #endif
 441
 442 /*
 443  * vmw_mob_build_pt - Build a pagetable
 444  *
 445  * @data_addr:      Array of DMA addresses to the underlying buffer
 446  *                  object's data pages.
 447  * @num_data_pages: Number of buffer object data pages.
 448  * @pt_pages:       Array of page pointers to the page table pages.
 449  *
 450  * Returns the number of page table pages actually used.
 451  * Uses atomic kmaps of highmem pages to avoid TLB thrashing.
 452  */
 453 static unsigned long vmw_mob_build_pt(struct vmw_piter *data_iter,
 454                                       unsigned long num_data_pages,
 455                                       struct vmw_piter *pt_iter)
 456 {
 457         unsigned long pt_size = num_data_pages * VMW_PPN_SIZE;
 458         unsigned long num_pt_pages = DIV_ROUND_UP(pt_size, PAGE_SIZE);
 459         unsigned long pt_page;
 460         u32 *addr, *save_addr;
 461         unsigned long i;
 462         struct page *page;
 463
 464         for (pt_page = 0; pt_page < num_pt_pages; ++pt_page) {
 465                 page = vmw_piter_page(pt_iter);
 466
 467                 save_addr = addr = kmap_atomic(page);
 468
 469                 for (i = 0; i < PAGE_SIZE / VMW_PPN_SIZE; ++i) {
 470                         vmw_mob_assign_ppn(&addr,
 471                                            vmw_piter_dma_addr(data_iter));
 472                         if (unlikely(--num_data_pages == 0))
 473                                 break;
 474                         WARN_ON(!vmw_piter_next(data_iter));
 475                 }
 476                 kunmap_atomic(save_addr);
 477                 vmw_piter_next(pt_iter);
 478         }
 479
 480         return num_pt_pages;
 481 }
 482
 483 /*
 484  * vmw_mob_build_pt - Set up a multilevel mob pagetable
 485  *
 486  * @mob:            Pointer to a mob whose page table needs setting up.
 487  * @data_addr       Array of DMA addresses to the buffer object's data
 488  *                  pages.
 489  * @num_data_pages: Number of buffer object data pages.
 490  *
 491  * Uses tail recursion to set up a multilevel mob page table.
 492  */
 493 static void vmw_mob_pt_setup(struct vmw_mob *mob,
 494                              struct vmw_piter data_iter,
 495                              unsigned long num_data_pages)
 496 {
 497         unsigned long num_pt_pages = 0;
 498         struct ttm_buffer_object *bo = mob->pt_bo;
 499         struct vmw_piter save_pt_iter = {0};
 500         struct vmw_piter pt_iter;
 501         const struct vmw_sg_table *vsgt;
 502         int ret;
 503
 504         BUG_ON(num_data_pages == 0);
 505
 506         ret = ttm_bo_reserve(bo, false, true, NULL);
 507         BUG_ON(ret != 0);
 508
 509         vsgt = vmw_bo_sg_table(bo);
 510         vmw_piter_start(&pt_iter, vsgt, 0);
 511         BUG_ON(!vmw_piter_next(&pt_iter));
 512         mob->pt_level = 0;
 513         while (likely(num_data_pages > 1)) {
 514                 ++mob->pt_level;
 515                 BUG_ON(mob->pt_level > 2);
 516                 save_pt_iter = pt_iter;
 517                 num_pt_pages = vmw_mob_build_pt(&data_iter, num_data_pages,
 518                                                 &pt_iter);
 519                 data_iter = save_pt_iter;
 520                 num_data_pages = num_pt_pages;
 521         }
 522
 523         mob->pt_root_page = vmw_piter_dma_addr(&save_pt_iter);
 524         ttm_bo_unreserve(bo);
 525 }
 526
 527 /*
 528  * vmw_mob_destroy - Destroy a mob, unpopulating first if necessary.
 529  *
 530  * @mob:            Pointer to a mob to destroy.
 531  */
 532 void vmw_mob_destroy(struct vmw_mob *mob)
 533 {
 534         if (mob->pt_bo) {
 535                 vmw_bo_unpin_unlocked(mob->pt_bo);
 536                 ttm_bo_put(mob->pt_bo);
 537                 mob->pt_bo = NULL;
 538         }
 539         kfree(mob);
 540 }
 541
 542 /*
 543  * vmw_mob_unbind - Hide a mob from the device.
 544  *
 545  * @dev_priv:       Pointer to a device private.
 546  * @mob_id:         Device id of the mob to unbind.
 547  */
 548 void vmw_mob_unbind(struct vmw_private *dev_priv,
 549                     struct vmw_mob *mob)
 550 {
 551         struct {
 552                 SVGA3dCmdHeader header;
 553                 SVGA3dCmdDestroyGBMob body;
 554         } *cmd;
 555         int ret;
 556         struct ttm_buffer_object *bo = mob->pt_bo;
 557
 558         if (bo) {
 559                 ret = ttm_bo_reserve(bo, false, true, NULL);
 560                 /*
 561                  * Noone else should be using this buffer.
 562                  */
 563                 BUG_ON(ret != 0);
 564         }
 565
 566         cmd = VMW_CMD_RESERVE(dev_priv, sizeof(*cmd));
 567         if (cmd) {
 568                 cmd->header.id = SVGA_3D_CMD_DESTROY_GB_MOB;
 569                 cmd->header.size = sizeof(cmd->body);
 570                 cmd->body.mobid = mob->id;
 571                 vmw_cmd_commit(dev_priv, sizeof(*cmd));
 572         }
 573
 574         if (bo) {
 575                 vmw_bo_fence_single(bo, NULL);
 576                 ttm_bo_unreserve(bo);
 577         }
 578         vmw_fifo_resource_dec(dev_priv);
 579 }
 580
 581 /*
 582  * vmw_mob_bind - Make a mob visible to the device after first
 583  *                populating it if necessary.
 584  *
 585  * @dev_priv:       Pointer to a device private.
 586  * @mob:            Pointer to the mob we're making visible.
 587  * @data_addr:      Array of DMA addresses to the data pages of the underlying
 588  *                  buffer object.
 589  * @num_data_pages: Number of data pages of the underlying buffer
 590  *                  object.
 591  * @mob_id:         Device id of the mob to bind
 592  *
 593  * This function is intended to be interfaced with the ttm_tt backend
 594  * code.
 595  */
 596 int vmw_mob_bind(struct vmw_private *dev_priv,
 597                  struct vmw_mob *mob,
 598                  const struct vmw_sg_table *vsgt,
 599                  unsigned long num_data_pages,
 600                  int32_t mob_id)
 601 {
 602         int ret;
 603         bool pt_set_up = false;
 604         struct vmw_piter data_iter;
 605         struct {
 606                 SVGA3dCmdHeader header;
 607                 SVGA3dCmdDefineGBMob64 body;
 608         } *cmd;
 609
 610         mob->id = mob_id;
 611         vmw_piter_start(&data_iter, vsgt, 0);
 612         if (unlikely(!vmw_piter_next(&data_iter)))
 613                 return 0;
 614
 615         if (likely(num_data_pages == 1)) {
 616                 mob->pt_level = VMW_MOBFMT_PTDEPTH_0;
 617                 mob->pt_root_page = vmw_piter_dma_addr(&data_iter);
 618         } else if (unlikely(mob->pt_bo == NULL)) {
 619                 ret = vmw_mob_pt_populate(dev_priv, mob);
 620                 if (unlikely(ret != 0))
 621                         return ret;
 622
 623                 vmw_mob_pt_setup(mob, data_iter, num_data_pages);
 624                 pt_set_up = true;
 625                 mob->pt_level += VMW_MOBFMT_PTDEPTH_1 - SVGA3D_MOBFMT_PT_1;
 626         }
 627
 628         vmw_fifo_resource_inc(dev_priv);
 629
 630         cmd = VMW_CMD_RESERVE(dev_priv, sizeof(*cmd));
 631         if (unlikely(cmd == NULL))
 632                 goto out_no_cmd_space;
 633
 634         cmd->header.id = SVGA_3D_CMD_DEFINE_GB_MOB64;
 635         cmd->header.size = sizeof(cmd->body);
 636         cmd->body.mobid = mob_id;
 637         cmd->body.ptDepth = mob->pt_level;
 638         cmd->body.base = mob->pt_root_page >> PAGE_SHIFT;
 639         cmd->body.sizeInBytes = num_data_pages * PAGE_SIZE;
 640
 641         vmw_cmd_commit(dev_priv, sizeof(*cmd));
 642
 643         return 0;
 644
 645 out_no_cmd_space:
 646         vmw_fifo_resource_dec(dev_priv);
 647         if (pt_set_up) {
 648                 vmw_bo_unpin_unlocked(mob->pt_bo);
 649                 ttm_bo_put(mob->pt_bo);
 650                 mob->pt_bo = NULL;
 651         }
 652
 653         return -ENOMEM;
 654 }