Pileus Git - ~andy/linux/blob - drivers/gpu/drm/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 #define pr_fmt(fmt) "[TTM] " fmt
  32
  33 #include <ttm/ttm_module.h>
  34 #include <ttm/ttm_bo_driver.h>
  35 #include <ttm/ttm_placement.h>
  36 #include <drm/drm_vma_manager.h>
  37 #include <linux/mm.h>
  38 #include <linux/rbtree.h>
  39 #include <linux/module.h>
  40 #include <linux/uaccess.h>
  41
  42 #define TTM_BO_VM_NUM_PREFAULT 16
  43
  44 static int ttm_bo_vm_fault_idle(struct ttm_buffer_object *bo,
  45                                 struct vm_area_struct *vma,
  46                                 struct vm_fault *vmf)
  47 {
  48         struct ttm_bo_device *bdev = bo->bdev;
  49         int ret = 0;
  50
  51         spin_lock(&bdev->fence_lock);
  52         if (likely(!test_bit(TTM_BO_PRIV_FLAG_MOVING, &bo->priv_flags)))
  53                 goto out_unlock;
  54
  55         /*
  56          * Quick non-stalling check for idle.
  57          */
  58         ret = ttm_bo_wait(bo, false, false, true);
  59         if (likely(ret == 0))
  60                 goto out_unlock;
  61
  62         /*
  63          * If possible, avoid waiting for GPU with mmap_sem
  64          * held.
  65          */
  66         if (vmf->flags & FAULT_FLAG_ALLOW_RETRY) {
  67                 ret = VM_FAULT_RETRY;
  68                 if (vmf->flags & FAULT_FLAG_RETRY_NOWAIT)
  69                         goto out_unlock;
  70
  71                 up_read(&vma->vm_mm->mmap_sem);
  72                 (void) ttm_bo_wait(bo, false, true, false);
  73                 goto out_unlock;
  74         }
  75
  76         /*
  77          * Ordinary wait.
  78          */
  79         ret = ttm_bo_wait(bo, false, true, false);
  80         if (unlikely(ret != 0))
  81                 ret = (ret != -ERESTARTSYS) ? VM_FAULT_SIGBUS :
  82                         VM_FAULT_NOPAGE;
  83
  84 out_unlock:
  85         spin_unlock(&bdev->fence_lock);
  86         return ret;
  87 }
  88
  89 static int ttm_bo_vm_fault(struct vm_area_struct *vma, struct vm_fault *vmf)
  90 {
  91         struct ttm_buffer_object *bo = (struct ttm_buffer_object *)
  92             vma->vm_private_data;
  93         struct ttm_bo_device *bdev = bo->bdev;
  94         unsigned long page_offset;
  95         unsigned long page_last;
  96         unsigned long pfn;
  97         struct ttm_tt *ttm = NULL;
  98         struct page *page;
  99         int ret;
 100         int i;
 101         unsigned long address = (unsigned long)vmf->virtual_address;
 102         int retval = VM_FAULT_NOPAGE;
 103         struct ttm_mem_type_manager *man =
 104                 &bdev->man[bo->mem.mem_type];
 105         struct vm_area_struct cvma;
 106
 107         /*
 108          * Work around locking order reversal in fault / nopfn
 109          * between mmap_sem and bo_reserve: Perform a trylock operation
 110          * for reserve, and if it fails, retry the fault after scheduling.
 111          */
 112
 113         ret = ttm_bo_reserve(bo, true, true, false, 0);
 114         if (unlikely(ret != 0)) {
 115                 if (ret == -EBUSY)
 116                         set_need_resched();
 117                 return VM_FAULT_NOPAGE;
 118         }
 119
 120         if (bdev->driver->fault_reserve_notify) {
 121                 ret = bdev->driver->fault_reserve_notify(bo);
 122                 switch (ret) {
 123                 case 0:
 124                         break;
 125                 case -EBUSY:
 126                         set_need_resched();
 127                 case -ERESTARTSYS:
 128                         retval = VM_FAULT_NOPAGE;
 129                         goto out_unlock;
 130                 default:
 131                         retval = VM_FAULT_SIGBUS;
 132                         goto out_unlock;
 133                 }
 134         }
 135
 136         /*
 137          * Wait for buffer data in transit, due to a pipelined
 138          * move.
 139          */
 140         ret = ttm_bo_vm_fault_idle(bo, vma, vmf);
 141         if (unlikely(ret != 0)) {
 142                 retval = ret;
 143                 goto out_unlock;
 144         }
 145
 146         ret = ttm_mem_io_lock(man, true);
 147         if (unlikely(ret != 0)) {
 148                 retval = VM_FAULT_NOPAGE;
 149                 goto out_unlock;
 150         }
 151         ret = ttm_mem_io_reserve_vm(bo);
 152         if (unlikely(ret != 0)) {
 153                 retval = VM_FAULT_SIGBUS;
 154                 goto out_io_unlock;
 155         }
 156
 157         page_offset = ((address - vma->vm_start) >> PAGE_SHIFT) +
 158             drm_vma_node_start(&bo->vma_node) - vma->vm_pgoff;
 159         page_last = vma_pages(vma) +
 160             drm_vma_node_start(&bo->vma_node) - vma->vm_pgoff;
 161
 162         if (unlikely(page_offset >= bo->num_pages)) {
 163                 retval = VM_FAULT_SIGBUS;
 164                 goto out_io_unlock;
 165         }
 166
 167         /*
 168          * Make a local vma copy to modify the page_prot member
 169          * and vm_flags if necessary. The vma parameter is protected
 170          * by mmap_sem in write mode.
 171          */
 172         cvma = *vma;
 173         cvma.vm_page_prot = vm_get_page_prot(cvma.vm_flags);
 174
 175         if (bo->mem.bus.is_iomem) {
 176                 cvma.vm_page_prot = ttm_io_prot(bo->mem.placement,
 177                                                 cvma.vm_page_prot);
 178         } else {
 179                 ttm = bo->ttm;
 180                 if (!(bo->mem.placement & TTM_PL_FLAG_CACHED))
 181                         cvma.vm_page_prot = ttm_io_prot(bo->mem.placement,
 182                                                         cvma.vm_page_prot);
 183
 184                 /* Allocate all page at once, most common usage */
 185                 if (ttm->bdev->driver->ttm_tt_populate(ttm)) {
 186                         retval = VM_FAULT_OOM;
 187                         goto out_io_unlock;
 188                 }
 189         }
 190
 191         /*
 192          * Speculatively prefault a number of pages. Only error on
 193          * first page.
 194          */
 195         for (i = 0; i < TTM_BO_VM_NUM_PREFAULT; ++i) {
 196                 if (bo->mem.bus.is_iomem)
 197                         pfn = ((bo->mem.bus.base + bo->mem.bus.offset) >> PAGE_SHIFT) + page_offset;
 198                 else {
 199                         page = ttm->pages[page_offset];
 200                         if (unlikely(!page && i == 0)) {
 201                                 retval = VM_FAULT_OOM;
 202                                 goto out_io_unlock;
 203                         } else if (unlikely(!page)) {
 204                                 break;
 205                         }
 206                         pfn = page_to_pfn(page);
 207                 }
 208
 209                 ret = vm_insert_mixed(&cvma, address, pfn);
 210                 /*
 211                  * Somebody beat us to this PTE or prefaulting to
 212                  * an already populated PTE, or prefaulting error.
 213                  */
 214
 215                 if (unlikely((ret == -EBUSY) || (ret != 0 && i > 0)))
 216                         break;
 217                 else if (unlikely(ret != 0)) {
 218                         retval =
 219                             (ret == -ENOMEM) ? VM_FAULT_OOM : VM_FAULT_SIGBUS;
 220                         goto out_io_unlock;
 221                 }
 222
 223                 address += PAGE_SIZE;
 224                 if (unlikely(++page_offset >= page_last))
 225                         break;
 226         }
 227 out_io_unlock:
 228         ttm_mem_io_unlock(man);
 229 out_unlock:
 230         ttm_bo_unreserve(bo);
 231         return retval;
 232 }
 233
 234 static void ttm_bo_vm_open(struct vm_area_struct *vma)
 235 {
 236         struct ttm_buffer_object *bo =
 237             (struct ttm_buffer_object *)vma->vm_private_data;
 238
 239         (void)ttm_bo_reference(bo);
 240 }
 241
 242 static void ttm_bo_vm_close(struct vm_area_struct *vma)
 243 {
 244         struct ttm_buffer_object *bo = (struct ttm_buffer_object *)vma->vm_private_data;
 245
 246         ttm_bo_unref(&bo);
 247         vma->vm_private_data = NULL;
 248 }
 249
 250 static const struct vm_operations_struct ttm_bo_vm_ops = {
 251         .fault = ttm_bo_vm_fault,
 252         .open = ttm_bo_vm_open,
 253         .close = ttm_bo_vm_close
 254 };
 255
 256 static struct ttm_buffer_object *ttm_bo_vm_lookup(struct ttm_bo_device *bdev,
 257                                                   unsigned long offset,
 258                                                   unsigned long pages)
 259 {
 260         struct drm_vma_offset_node *node;
 261         struct ttm_buffer_object *bo = NULL;
 262
 263         drm_vma_offset_lock_lookup(&bdev->vma_manager);
 264
 265         node = drm_vma_offset_lookup_locked(&bdev->vma_manager, offset, pages);
 266         if (likely(node)) {
 267                 bo = container_of(node, struct ttm_buffer_object, vma_node);
 268                 if (!kref_get_unless_zero(&bo->kref))
 269                         bo = NULL;
 270         }
 271
 272         drm_vma_offset_unlock_lookup(&bdev->vma_manager);
 273
 274         if (!bo)
 275                 pr_err("Could not find buffer object to map\n");
 276
 277         return bo;
 278 }
 279
 280 int ttm_bo_mmap(struct file *filp, struct vm_area_struct *vma,
 281                 struct ttm_bo_device *bdev)
 282 {
 283         struct ttm_bo_driver *driver;
 284         struct ttm_buffer_object *bo;
 285         int ret;
 286
 287         bo = ttm_bo_vm_lookup(bdev, vma->vm_pgoff, vma_pages(vma));
 288         if (unlikely(!bo))
 289                 return -EINVAL;
 290
 291         driver = bo->bdev->driver;
 292         if (unlikely(!driver->verify_access)) {
 293                 ret = -EPERM;
 294                 goto out_unref;
 295         }
 296         ret = driver->verify_access(bo, filp);
 297         if (unlikely(ret != 0))
 298                 goto out_unref;
 299
 300         vma->vm_ops = &ttm_bo_vm_ops;
 301
 302         /*
 303          * Note: We're transferring the bo reference to
 304          * vma->vm_private_data here.
 305          */
 306
 307         vma->vm_private_data = bo;
 308         vma->vm_flags |= VM_IO | VM_MIXEDMAP | VM_DONTEXPAND | VM_DONTDUMP;
 309         return 0;
 310 out_unref:
 311         ttm_bo_unref(&bo);
 312         return ret;
 313 }
 314 EXPORT_SYMBOL(ttm_bo_mmap);
 315
 316 int ttm_fbdev_mmap(struct vm_area_struct *vma, struct ttm_buffer_object *bo)
 317 {
 318         if (vma->vm_pgoff != 0)
 319                 return -EACCES;
 320
 321         vma->vm_ops = &ttm_bo_vm_ops;
 322         vma->vm_private_data = ttm_bo_reference(bo);
 323         vma->vm_flags |= VM_IO | VM_MIXEDMAP | VM_DONTEXPAND;
 324         return 0;
 325 }
 326 EXPORT_SYMBOL(ttm_fbdev_mmap);