sys/dev/drm/drm_vm.c

   1 /*-
   2  * Copyright 2003 Eric Anholt
   3  * All Rights Reserved.
   4  *
   5  * Permission is hereby granted, free of charge, to any person obtaining a
   6  * copy of this software and associated documentation files (the "Software"),
   7  * to deal in the Software without restriction, including without limitation
   8  * the rights to use, copy, modify, merge, publish, distribute, sublicense,
   9  * and/or sell copies of the Software, and to permit persons to whom the
  10  * Software is furnished to do so, subject to the following conditions:
  11  *
  12  * The above copyright notice and this permission notice (including the next
  13  * paragraph) shall be included in all copies or substantial portions of the
  14  * Software.
  15  *
  16  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
  17  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  18  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
  19  * ERIC ANHOLT BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER
  20  * IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
  21  * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
  22  *
  23  * $FreeBSD: head/sys/dev/drm2/drm_vm.c 235783 2012-05-22 11:07:44Z kib $"
  24  */
  25
  26 /** @file drm_vm.c
  27  * Support code for mmaping of DRM maps.
  28  */
  29
  30 #include <sys/conf.h>
  31 #include <sys/devfs.h>
  32 #include <sys/mutex2.h>
  33 #include <vm/vm_page.h>
  34 #include <vm/vm_pager.h>
  35
  36 #include <drm/drmP.h>
  37
  38 int drm_mmap(struct dev_mmap_args *ap)
  39 {
  40         struct cdev *kdev = ap->a_head.a_dev;
  41         vm_offset_t offset = ap->a_offset;
  42         struct drm_device *dev = drm_get_device_from_kdev(kdev);
  43         struct drm_file *file_priv = NULL;
  44         struct drm_local_map *map = NULL;
  45         struct drm_map_list *r_list;
  46         int error;
  47
  48         enum drm_map_type type;
  49         vm_paddr_t phys;
  50
  51         /* d_mmap gets called twice, we can only reference file_priv during
  52          * the first call.  We need to assume that if error is EBADF the
  53          * call was succesful and the client is authenticated.
  54          */
  55         error = devfs_get_cdevpriv(ap->a_fp, (void **)&file_priv);
  56         if (error == ENOENT) {
  57                 DRM_ERROR("Could not find authenticator!\n");
  58                 return EINVAL;
  59         }
  60
  61         if (file_priv && !file_priv->authenticated)
  62                 return EACCES;
  63
  64         DRM_DEBUG("called with offset %016jx\n", (uintmax_t)offset);
  65         if (dev->dma && offset < ptoa(dev->dma->page_count)) {
  66                 drm_device_dma_t *dma = dev->dma;
  67
  68                 spin_lock(&dev->dma_lock);
  69
  70                 if (dma->pagelist != NULL) {
  71                         unsigned long page = offset >> PAGE_SHIFT;
  72                         unsigned long phys = dma->pagelist[page];
  73
  74                         spin_unlock(&dev->dma_lock);
  75                         // XXX *paddr = phys;
  76                         ap->a_result = phys;
  77                         return 0;
  78                 } else {
  79                         spin_unlock(&dev->dma_lock);
  80                         return -1;
  81                 }
  82         }
  83
  84         /* A sequential search of a linked list is
  85            fine here because: 1) there will only be
  86            about 5-10 entries in the list and, 2) a
  87            DRI client only has to do this mapping
  88            once, so it doesn't have to be optimized
  89            for performance, even if the list was a
  90            bit longer.
  91         */
  92         DRM_LOCK(dev);
  93         list_for_each_entry(r_list, &dev->maplist, head) {
  94                 if (r_list->map && r_list->map->offset >> DRM_MAP_HANDLE_SHIFT ==
  95                     (unsigned long)r_list->map->handle >> DRM_MAP_HANDLE_SHIFT) {
  96                         map = r_list->map;
  97                         break;
  98                 }
  99         }
 100
 101         if (map == NULL) {
 102                 DRM_DEBUG("Can't find map, request offset = %016jx\n",
 103                     (uintmax_t)offset);
 104                 list_for_each_entry(r_list, &dev->maplist, head) {
 105                         DRM_DEBUG("map offset = %016lx, handle = %016lx\n",
 106                             r_list->map->offset, (unsigned long)r_list->map->handle);
 107                 }
 108                 DRM_UNLOCK(dev);
 109                 return -1;
 110         }
 111         if (((map->flags & _DRM_RESTRICTED) && !DRM_SUSER(DRM_CURPROC))) {
 112                 DRM_UNLOCK(dev);
 113                 DRM_DEBUG("restricted map\n");
 114                 return -1;
 115         }
 116         type = map->type;
 117         DRM_UNLOCK(dev);
 118
 119         offset = offset & ((1ULL << DRM_MAP_HANDLE_SHIFT) - 1);
 120
 121         switch (type) {
 122         case _DRM_FRAME_BUFFER:
 123         case _DRM_AGP:
 124 #if 0   /* XXX */
 125                 *memattr = VM_MEMATTR_WRITE_COMBINING;
 126 #endif
 127                 /* FALLTHROUGH */
 128         case _DRM_REGISTERS:
 129                 phys = map->offset + offset;
 130                 break;
 131         case _DRM_SCATTER_GATHER:
 132 #if 0   /* XXX */
 133                 *memattr = VM_MEMATTR_WRITE_COMBINING;
 134 #endif
 135                 /* FALLTHROUGH */
 136         case _DRM_CONSISTENT:
 137         case _DRM_SHM:
 138                 phys = vtophys((char *)map->virtual + offset);
 139                 break;
 140         default:
 141                 DRM_ERROR("bad map type %d\n", type);
 142                 return -1;      /* This should never happen. */
 143         }
 144
 145         ap->a_result = atop(phys);
 146         return 0;
 147 }
 148
 149 /* XXX The following is just temporary hack to replace the
 150  * vm_phys_fictitious functions available on FreeBSD
 151  */
 152 #define VM_PHYS_FICTITIOUS_NSEGS        8
 153 static struct vm_phys_fictitious_seg {
 154         vm_paddr_t      start;
 155         vm_paddr_t      end;
 156         vm_page_t       first_page;
 157 } vm_phys_fictitious_segs[VM_PHYS_FICTITIOUS_NSEGS];
 158 static struct mtx vm_phys_fictitious_reg_mtx = MTX_INITIALIZER;
 159
 160 MALLOC_DEFINE(M_FICT_PAGES, "", "");
 161
 162 vm_page_t
 163 vm_phys_fictitious_to_vm_page(vm_paddr_t pa)
 164 {
 165         struct vm_phys_fictitious_seg *seg;
 166         vm_page_t m;
 167         int segind;
 168
 169         m = NULL;
 170         for (segind = 0; segind < VM_PHYS_FICTITIOUS_NSEGS; segind++) {
 171                 seg = &vm_phys_fictitious_segs[segind];
 172                 if (pa >= seg->start && pa < seg->end) {
 173                         m = &seg->first_page[atop(pa - seg->start)];
 174                         KASSERT((m->flags & PG_FICTITIOUS) != 0,
 175                             ("%p not fictitious", m));
 176                         break;
 177                 }
 178         }
 179         return (m);
 180 }
 181
 182 int
 183 vm_phys_fictitious_reg_range(vm_paddr_t start, vm_paddr_t end,
 184     vm_memattr_t memattr)
 185 {
 186         struct vm_phys_fictitious_seg *seg;
 187         vm_page_t fp;
 188         long i, page_count;
 189         int segind;
 190
 191         page_count = (end - start) / PAGE_SIZE;
 192
 193         fp = kmalloc(page_count * sizeof(struct vm_page), M_FICT_PAGES,
 194                     M_WAITOK | M_ZERO);
 195
 196         for (i = 0; i < page_count; i++) {
 197                 vm_page_initfake(&fp[i], start + PAGE_SIZE * i, memattr);
 198                 fp[i].flags &= ~(PG_BUSY | PG_UNMANAGED);
 199         }
 200         mtx_lock(&vm_phys_fictitious_reg_mtx);
 201         for (segind = 0; segind < VM_PHYS_FICTITIOUS_NSEGS; segind++) {
 202                 seg = &vm_phys_fictitious_segs[segind];
 203                 if (seg->start == 0 && seg->end == 0) {
 204                         seg->start = start;
 205                         seg->end = end;
 206                         seg->first_page = fp;
 207                         mtx_unlock(&vm_phys_fictitious_reg_mtx);
 208                         return (0);
 209                 }
 210         }
 211         mtx_unlock(&vm_phys_fictitious_reg_mtx);
 212         kfree(fp, M_FICT_PAGES);
 213         return (EBUSY);
 214 }
 215
 216 void
 217 vm_phys_fictitious_unreg_range(vm_paddr_t start, vm_paddr_t end)
 218 {
 219         struct vm_phys_fictitious_seg *seg;
 220         vm_page_t fp;
 221         int segind;
 222
 223         mtx_lock(&vm_phys_fictitious_reg_mtx);
 224         for (segind = 0; segind < VM_PHYS_FICTITIOUS_NSEGS; segind++) {
 225                 seg = &vm_phys_fictitious_segs[segind];
 226                 if (seg->start == start && seg->end == end) {
 227                         seg->start = seg->end = 0;
 228                         fp = seg->first_page;
 229                         seg->first_page = NULL;
 230                         mtx_unlock(&vm_phys_fictitious_reg_mtx);
 231                         kfree(fp, M_FICT_PAGES);
 232                         return;
 233                 }
 234         }
 235         mtx_unlock(&vm_phys_fictitious_reg_mtx);
 236         KASSERT(0, ("Unregistering not registered fictitious range"));
 237 }