sys/dev/drm2/ttm/ttm_bo_vm.c

   1 /**************************************************************************
   2  *
   3  * Copyright (c) 2006-2009 VMware, Inc., Palo Alto, CA., USA
   4  * All Rights Reserved.
   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  * Authors: Thomas Hellstrom <thellstrom-at-vmware-dot-com>
  29  */
  30 /*
  31  * Copyright (c) 2013 The FreeBSD Foundation
  32  * All rights reserved.
  33  *
  34  * Portions of this software were developed by Konstantin Belousov
  35  * <kib@FreeBSD.org> under sponsorship from the FreeBSD Foundation.
  36  *
  37  *$FreeBSD: head/sys/dev/drm2/ttm/ttm_bo_vm.c 253710 2013-07-27 16:44:37Z kib $
  38  */
  39
  40 #include "opt_vm.h"
  41
  42 #include <dev/drm2/drmP.h>
  43 #include <dev/drm2/ttm/ttm_module.h>
  44 #include <dev/drm2/ttm/ttm_bo_driver.h>
  45 #include <dev/drm2/ttm/ttm_placement.h>
  46
  47 #include <vm/vm.h>
  48 #include <vm/vm_page.h>
  49
  50 #define TTM_BO_VM_NUM_PREFAULT 16
  51
  52 RB_GENERATE(ttm_bo_device_buffer_objects, ttm_buffer_object, vm_rb,
  53     ttm_bo_cmp_rb_tree_items);
  54
  55 int
  56 ttm_bo_cmp_rb_tree_items(struct ttm_buffer_object *a,
  57     struct ttm_buffer_object *b)
  58 {
  59
  60         if (a->vm_node->start < b->vm_node->start) {
  61                 return (-1);
  62         } else if (a->vm_node->start > b->vm_node->start) {
  63                 return (1);
  64         } else {
  65                 return (0);
  66         }
  67 }
  68
  69 static struct ttm_buffer_object *ttm_bo_vm_lookup_rb(struct ttm_bo_device *bdev,
  70                                                      unsigned long page_start,
  71                                                      unsigned long num_pages)
  72 {
  73         unsigned long cur_offset;
  74         struct ttm_buffer_object *bo;
  75         struct ttm_buffer_object *best_bo = NULL;
  76
  77         RB_FOREACH(bo, ttm_bo_device_buffer_objects, &bdev->addr_space_rb) {
  78                 cur_offset = bo->vm_node->start;
  79                 if (page_start >= cur_offset) {
  80                         best_bo = bo;
  81                         if (page_start == cur_offset)
  82                                 break;
  83                 }
  84         }
  85
  86         if (unlikely(best_bo == NULL))
  87                 return NULL;
  88
  89         if (unlikely((best_bo->vm_node->start + best_bo->num_pages) <
  90                      (page_start + num_pages)))
  91                 return NULL;
  92
  93         return best_bo;
  94 }
  95
  96 static int
  97 ttm_bo_vm_fault(vm_object_t vm_obj, vm_ooffset_t offset,
  98     int prot, vm_page_t *mres)
  99 {
 100
 101         struct ttm_buffer_object *bo = vm_obj->handle;
 102         struct ttm_bo_device *bdev = bo->bdev;
 103         struct ttm_tt *ttm = NULL;
 104         vm_page_t m, m1, oldm;
 105         int ret;
 106         int retval = VM_PAGER_OK;
 107         struct ttm_mem_type_manager *man =
 108                 &bdev->man[bo->mem.mem_type];
 109
 110         vm_object_pip_add(vm_obj, 1);
 111         oldm = *mres;
 112         if (oldm != NULL) {
 113                 vm_page_lock(oldm);
 114                 vm_page_remove(oldm);
 115                 vm_page_unlock(oldm);
 116                 *mres = NULL;
 117         } else
 118                 oldm = NULL;
 119 retry:
 120         VM_OBJECT_WUNLOCK(vm_obj);
 121         m = NULL;
 122
 123 reserve:
 124         ret = ttm_bo_reserve(bo, false, false, false, 0);
 125         if (unlikely(ret != 0)) {
 126                 if (ret == -EBUSY) {
 127                         kern_yield(0);
 128                         goto reserve;
 129                 }
 130         }
 131
 132         if (bdev->driver->fault_reserve_notify) {
 133                 ret = bdev->driver->fault_reserve_notify(bo);
 134                 switch (ret) {
 135                 case 0:
 136                         break;
 137                 case -EBUSY:
 138                 case -ERESTART:
 139                 case -EINTR:
 140                         kern_yield(0);
 141                         goto reserve;
 142                 default:
 143                         retval = VM_PAGER_ERROR;
 144                         goto out_unlock;
 145                 }
 146         }
 147
 148         /*
 149          * Wait for buffer data in transit, due to a pipelined
 150          * move.
 151          */
 152
 153         mtx_lock(&bdev->fence_lock);
 154         if (test_bit(TTM_BO_PRIV_FLAG_MOVING, &bo->priv_flags)) {
 155                 ret = ttm_bo_wait(bo, false, true, false);
 156                 mtx_unlock(&bdev->fence_lock);
 157                 if (unlikely(ret != 0)) {
 158                         retval = VM_PAGER_ERROR;
 159                         goto out_unlock;
 160                 }
 161         } else
 162                 mtx_unlock(&bdev->fence_lock);
 163
 164         ret = ttm_mem_io_lock(man, true);
 165         if (unlikely(ret != 0)) {
 166                 retval = VM_PAGER_ERROR;
 167                 goto out_unlock;
 168         }
 169         ret = ttm_mem_io_reserve_vm(bo);
 170         if (unlikely(ret != 0)) {
 171                 retval = VM_PAGER_ERROR;
 172                 goto out_io_unlock;
 173         }
 174
 175         /*
 176          * Strictly, we're not allowed to modify vma->vm_page_prot here,
 177          * since the mmap_sem is only held in read mode. However, we
 178          * modify only the caching bits of vma->vm_page_prot and
 179          * consider those bits protected by
 180          * the bo->mutex, as we should be the only writers.
 181          * There shouldn't really be any readers of these bits except
 182          * within vm_insert_mixed()? fork?
 183          *
 184          * TODO: Add a list of vmas to the bo, and change the
 185          * vma->vm_page_prot when the object changes caching policy, with
 186          * the correct locks held.
 187          */
 188         if (!bo->mem.bus.is_iomem) {
 189                 /* Allocate all page at once, most common usage */
 190                 ttm = bo->ttm;
 191                 if (ttm->bdev->driver->ttm_tt_populate(ttm)) {
 192                         retval = VM_PAGER_ERROR;
 193                         goto out_io_unlock;
 194                 }
 195         }
 196
 197         if (bo->mem.bus.is_iomem) {
 198                 m = vm_phys_fictitious_to_vm_page(bo->mem.bus.base +
 199                     bo->mem.bus.offset + offset);
 200                 pmap_page_set_memattr(m, ttm_io_prot(bo->mem.placement));
 201         } else {
 202                 ttm = bo->ttm;
 203                 m = ttm->pages[OFF_TO_IDX(offset)];
 204                 if (unlikely(!m)) {
 205                         retval = VM_PAGER_ERROR;
 206                         goto out_io_unlock;
 207                 }
 208                 pmap_page_set_memattr(m,
 209                     (bo->mem.placement & TTM_PL_FLAG_CACHED) ?
 210                     VM_MEMATTR_WRITE_BACK : ttm_io_prot(bo->mem.placement));
 211         }
 212
 213         VM_OBJECT_WLOCK(vm_obj);
 214         if ((m->flags & VPO_BUSY) != 0) {
 215                 vm_page_sleep(m, "ttmpbs");
 216                 ttm_mem_io_unlock(man);
 217                 ttm_bo_unreserve(bo);
 218                 goto retry;
 219         }
 220         m->valid = VM_PAGE_BITS_ALL;
 221         *mres = m;
 222         m1 = vm_page_lookup(vm_obj, OFF_TO_IDX(offset));
 223         if (m1 == NULL) {
 224                 vm_page_insert(m, vm_obj, OFF_TO_IDX(offset));
 225         } else {
 226                 KASSERT(m == m1,
 227                     ("inconsistent insert bo %p m %p m1 %p offset %jx",
 228                     bo, m, m1, (uintmax_t)offset));
 229         }
 230         vm_page_busy(m);
 231
 232         if (oldm != NULL) {
 233                 vm_page_lock(oldm);
 234                 vm_page_free(oldm);
 235                 vm_page_unlock(oldm);
 236         }
 237
 238 out_io_unlock1:
 239         ttm_mem_io_unlock(man);
 240 out_unlock1:
 241         ttm_bo_unreserve(bo);
 242         vm_object_pip_wakeup(vm_obj);
 243         return (retval);
 244
 245 out_io_unlock:
 246         VM_OBJECT_WLOCK(vm_obj);
 247         goto out_io_unlock1;
 248
 249 out_unlock:
 250         VM_OBJECT_WLOCK(vm_obj);
 251         goto out_unlock1;
 252 }
 253
 254 static int
 255 ttm_bo_vm_ctor(void *handle, vm_ooffset_t size, vm_prot_t prot,
 256     vm_ooffset_t foff, struct ucred *cred, u_short *color)
 257 {
 258
 259         /*
 260          * We don't acquire a reference on bo->kref here, because it was
 261          * already done in ttm_bo_mmap_single().
 262          */
 263
 264         *color = 0;
 265         return (0);
 266 }
 267
 268 static void
 269 ttm_bo_vm_dtor(void *handle)
 270 {
 271         struct ttm_buffer_object *bo = handle;
 272
 273         ttm_bo_unref(&bo);
 274 }
 275
 276 static struct cdev_pager_ops ttm_pager_ops = {
 277         .cdev_pg_fault = ttm_bo_vm_fault,
 278         .cdev_pg_ctor = ttm_bo_vm_ctor,
 279         .cdev_pg_dtor = ttm_bo_vm_dtor
 280 };
 281
 282 int
 283 ttm_bo_mmap_single(struct ttm_bo_device *bdev, vm_ooffset_t *offset, vm_size_t size,
 284     struct vm_object **obj_res, int nprot)
 285 {
 286         struct ttm_bo_driver *driver;
 287         struct ttm_buffer_object *bo;
 288         struct vm_object *vm_obj;
 289         int ret;
 290
 291         rw_wlock(&bdev->vm_lock);
 292         bo = ttm_bo_vm_lookup_rb(bdev, OFF_TO_IDX(*offset), OFF_TO_IDX(size));
 293         if (likely(bo != NULL))
 294                 refcount_acquire(&bo->kref);
 295         rw_wunlock(&bdev->vm_lock);
 296
 297         if (unlikely(bo == NULL)) {
 298                 printf("[TTM] Could not find buffer object to map\n");
 299                 return (EINVAL);
 300         }
 301
 302         driver = bo->bdev->driver;
 303         if (unlikely(!driver->verify_access)) {
 304                 ret = EPERM;
 305                 goto out_unref;
 306         }
 307         ret = -driver->verify_access(bo);
 308         if (unlikely(ret != 0))
 309                 goto out_unref;
 310
 311         vm_obj = cdev_pager_allocate(bo, OBJT_MGTDEVICE, &ttm_pager_ops,
 312             size, nprot, 0, curthread->td_ucred);
 313         if (vm_obj == NULL) {
 314                 ret = EINVAL;
 315                 goto out_unref;
 316         }
 317         /*
 318          * Note: We're transferring the bo reference to vm_obj->handle here.
 319          */
 320         *offset = 0;
 321         *obj_res = vm_obj;
 322         return 0;
 323 out_unref:
 324         ttm_bo_unref(&bo);
 325         return ret;
 326 }
 327
 328 #if 0
 329 int ttm_fbdev_mmap(struct vm_area_struct *vma, struct ttm_buffer_object *bo)
 330 {
 331         if (vma->vm_pgoff != 0)
 332                 return -EACCES;
 333
 334         vma->vm_ops = &ttm_bo_vm_ops;
 335         vma->vm_private_data = ttm_bo_reference(bo);
 336         vma->vm_flags |= VM_IO | VM_MIXEDMAP | VM_DONTEXPAND;
 337         return 0;
 338 }
 339
 340 ssize_t ttm_bo_io(struct ttm_bo_device *bdev, struct file *filp,
 341                   const char __user *wbuf, char __user *rbuf, size_t count,
 342                   loff_t *f_pos, bool write)
 343 {
 344         struct ttm_buffer_object *bo;
 345         struct ttm_bo_driver *driver;
 346         struct ttm_bo_kmap_obj map;
 347         unsigned long dev_offset = (*f_pos >> PAGE_SHIFT);
 348         unsigned long kmap_offset;
 349         unsigned long kmap_end;
 350         unsigned long kmap_num;
 351         size_t io_size;
 352         unsigned int page_offset;
 353         char *virtual;
 354         int ret;
 355         bool no_wait = false;
 356         bool dummy;
 357
 358         read_lock(&bdev->vm_lock);
 359         bo = ttm_bo_vm_lookup_rb(bdev, dev_offset, 1);
 360         if (likely(bo != NULL))
 361                 ttm_bo_reference(bo);
 362         read_unlock(&bdev->vm_lock);
 363
 364         if (unlikely(bo == NULL))
 365                 return -EFAULT;
 366
 367         driver = bo->bdev->driver;
 368         if (unlikely(!driver->verify_access)) {
 369                 ret = -EPERM;
 370                 goto out_unref;
 371         }
 372
 373         ret = driver->verify_access(bo, filp);
 374         if (unlikely(ret != 0))
 375                 goto out_unref;
 376
 377         kmap_offset = dev_offset - bo->vm_node->start;
 378         if (unlikely(kmap_offset >= bo->num_pages)) {
 379                 ret = -EFBIG;
 380                 goto out_unref;
 381         }
 382
 383         page_offset = *f_pos & ~PAGE_MASK;
 384         io_size = bo->num_pages - kmap_offset;
 385         io_size = (io_size << PAGE_SHIFT) - page_offset;
 386         if (count < io_size)
 387                 io_size = count;
 388
 389         kmap_end = (*f_pos + count - 1) >> PAGE_SHIFT;
 390         kmap_num = kmap_end - kmap_offset + 1;
 391
 392         ret = ttm_bo_reserve(bo, true, no_wait, false, 0);
 393
 394         switch (ret) {
 395         case 0:
 396                 break;
 397         case -EBUSY:
 398                 ret = -EAGAIN;
 399                 goto out_unref;
 400         default:
 401                 goto out_unref;
 402         }
 403
 404         ret = ttm_bo_kmap(bo, kmap_offset, kmap_num, &map);
 405         if (unlikely(ret != 0)) {
 406                 ttm_bo_unreserve(bo);
 407                 goto out_unref;
 408         }
 409
 410         virtual = ttm_kmap_obj_virtual(&map, &dummy);
 411         virtual += page_offset;
 412
 413         if (write)
 414                 ret = copy_from_user(virtual, wbuf, io_size);
 415         else
 416                 ret = copy_to_user(rbuf, virtual, io_size);
 417
 418         ttm_bo_kunmap(&map);
 419         ttm_bo_unreserve(bo);
 420         ttm_bo_unref(&bo);
 421
 422         if (unlikely(ret != 0))
 423                 return -EFBIG;
 424
 425         *f_pos += io_size;
 426
 427         return io_size;
 428 out_unref:
 429         ttm_bo_unref(&bo);
 430         return ret;
 431 }
 432
 433 ssize_t ttm_bo_fbdev_io(struct ttm_buffer_object *bo, const char __user *wbuf,
 434                         char __user *rbuf, size_t count, loff_t *f_pos,
 435                         bool write)
 436 {
 437         struct ttm_bo_kmap_obj map;
 438         unsigned long kmap_offset;
 439         unsigned long kmap_end;
 440         unsigned long kmap_num;
 441         size_t io_size;
 442         unsigned int page_offset;
 443         char *virtual;
 444         int ret;
 445         bool no_wait = false;
 446         bool dummy;
 447
 448         kmap_offset = (*f_pos >> PAGE_SHIFT);
 449         if (unlikely(kmap_offset >= bo->num_pages))
 450                 return -EFBIG;
 451
 452         page_offset = *f_pos & ~PAGE_MASK;
 453         io_size = bo->num_pages - kmap_offset;
 454         io_size = (io_size << PAGE_SHIFT) - page_offset;
 455         if (count < io_size)
 456                 io_size = count;
 457
 458         kmap_end = (*f_pos + count - 1) >> PAGE_SHIFT;
 459         kmap_num = kmap_end - kmap_offset + 1;
 460
 461         ret = ttm_bo_reserve(bo, true, no_wait, false, 0);
 462
 463         switch (ret) {
 464         case 0:
 465                 break;
 466         case -EBUSY:
 467                 return -EAGAIN;
 468         default:
 469                 return ret;
 470         }
 471
 472         ret = ttm_bo_kmap(bo, kmap_offset, kmap_num, &map);
 473         if (unlikely(ret != 0)) {
 474                 ttm_bo_unreserve(bo);
 475                 return ret;
 476         }
 477
 478         virtual = ttm_kmap_obj_virtual(&map, &dummy);
 479         virtual += page_offset;
 480
 481         if (write)
 482                 ret = copy_from_user(virtual, wbuf, io_size);
 483         else
 484                 ret = copy_to_user(rbuf, virtual, io_size);
 485
 486         ttm_bo_kunmap(&map);
 487         ttm_bo_unreserve(bo);
 488         ttm_bo_unref(&bo);
 489
 490         if (unlikely(ret != 0))
 491                 return ret;
 492
 493         *f_pos += io_size;
 494
 495         return io_size;
 496 }
 497 #endif