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 #include <asm/pgtable.h>
  38 #include "drm_legacy.h"
  39
  40 int drm_mmap(struct dev_mmap_args *ap)
  41 {
  42         struct cdev *kdev = ap->a_head.a_dev;
  43         vm_offset_t offset = ap->a_offset;
  44         struct drm_device *dev = drm_get_device_from_kdev(kdev);
  45         struct drm_file *file_priv = NULL;
  46         struct drm_local_map *map = NULL;
  47         int error;
  48         struct drm_hash_item *hash;
  49
  50         enum drm_map_type type;
  51         vm_paddr_t phys;
  52
  53         /* d_mmap gets called twice, we can only reference file_priv during
  54          * the first call.  We need to assume that if error is EBADF the
  55          * call was succesful and the client is authenticated.
  56          */
  57         error = devfs_get_cdevpriv(ap->a_fp, (void **)&file_priv);
  58         if (error == ENOENT) {
  59                 DRM_ERROR("Could not find authenticator!\n");
  60                 return EINVAL;
  61         }
  62
  63         if (file_priv && !file_priv->authenticated)
  64                 return EACCES;
  65
  66         DRM_DEBUG("called with offset %016jx\n", (uintmax_t)offset);
  67         if (dev->dma && offset < ptoa(dev->dma->page_count)) {
  68                 struct drm_device_dma *dma = dev->dma;
  69
  70                 spin_lock(&dev->dma_lock);
  71
  72                 if (dma->pagelist != NULL) {
  73                         unsigned long page = offset >> PAGE_SHIFT;
  74                         unsigned long phys = dma->pagelist[page];
  75
  76                         spin_unlock(&dev->dma_lock);
  77                         // XXX *paddr = phys;
  78                         ap->a_result = phys;
  79                         return 0;
  80                 } else {
  81                         spin_unlock(&dev->dma_lock);
  82                         return -1;
  83                 }
  84         }
  85
  86         /* A sequential search of a linked list is
  87            fine here because: 1) there will only be
  88            about 5-10 entries in the list and, 2) a
  89            DRI client only has to do this mapping
  90            once, so it doesn't have to be optimized
  91            for performance, even if the list was a
  92            bit longer.
  93         */
  94         DRM_LOCK(dev);
  95
  96         if (drm_ht_find_item(&dev->map_hash, offset, &hash)) {
  97                 DRM_ERROR("Could not find map\n");
  98                 return -EINVAL;
  99         }
 100
 101         map = drm_hash_entry(hash, struct drm_map_list, hash)->map;
 102         if (map == NULL) {
 103                 DRM_DEBUG("Can't find map, request offset = %016jx\n",
 104                     (uintmax_t)offset);
 105                 DRM_UNLOCK(dev);
 106                 return -1;
 107         }
 108         if (((map->flags & _DRM_RESTRICTED) && !capable(CAP_SYS_ADMIN))) {
 109                 DRM_UNLOCK(dev);
 110                 DRM_DEBUG("restricted map\n");
 111                 return -1;
 112         }
 113
 114         type = map->type;
 115         DRM_UNLOCK(dev);
 116
 117         switch (type) {
 118         case _DRM_FRAME_BUFFER:
 119         case _DRM_AGP:
 120 #if 0   /* XXX */
 121                 *memattr = VM_MEMATTR_WRITE_COMBINING;
 122 #endif
 123                 /* FALLTHROUGH */
 124         case _DRM_REGISTERS:
 125                 phys = map->offset + offset;
 126                 break;
 127         case _DRM_SCATTER_GATHER:
 128 #if 0   /* XXX */
 129                 *memattr = VM_MEMATTR_WRITE_COMBINING;
 130 #endif
 131                 /* FALLTHROUGH */
 132         case _DRM_CONSISTENT:
 133         case _DRM_SHM:
 134                 phys = vtophys((char *)map->handle + offset);
 135                 break;
 136         default:
 137                 DRM_ERROR("bad map type %d\n", type);
 138                 return -1;      /* This should never happen. */
 139         }
 140
 141         ap->a_result = atop(phys);
 142         return 0;
 143 }
 144
 145 /* XXX The following is just temporary hack to replace the
 146  * vm_phys_fictitious functions available on FreeBSD
 147  */
 148 #define VM_PHYS_FICTITIOUS_NSEGS        8
 149 static struct vm_phys_fictitious_seg {
 150         vm_paddr_t      start;
 151         vm_paddr_t      end;
 152         vm_page_t       first_page;
 153 } vm_phys_fictitious_segs[VM_PHYS_FICTITIOUS_NSEGS];
 154 static struct mtx vm_phys_fictitious_reg_mtx = MTX_INITIALIZER("vmphy");
 155
 156 vm_page_t
 157 vm_phys_fictitious_to_vm_page(vm_paddr_t pa)
 158 {
 159         struct vm_phys_fictitious_seg *seg;
 160         vm_page_t m;
 161         int segind;
 162
 163         m = NULL;
 164         for (segind = 0; segind < VM_PHYS_FICTITIOUS_NSEGS; segind++) {
 165                 seg = &vm_phys_fictitious_segs[segind];
 166                 if (pa >= seg->start && pa < seg->end) {
 167                         m = &seg->first_page[atop(pa - seg->start)];
 168                         KASSERT((m->flags & PG_FICTITIOUS) != 0,
 169                             ("%p not fictitious", m));
 170                         break;
 171                 }
 172         }
 173         return (m);
 174 }
 175
 176 int
 177 vm_phys_fictitious_reg_range(vm_paddr_t start, vm_paddr_t end,
 178     vm_memattr_t memattr)
 179 {
 180         struct vm_phys_fictitious_seg *seg;
 181         vm_page_t fp;
 182         long i, page_count;
 183         int segind;
 184
 185         page_count = (end - start) / PAGE_SIZE;
 186
 187         fp = kmalloc(page_count * sizeof(struct vm_page), M_DRM,
 188                     M_WAITOK | M_ZERO);
 189
 190         for (i = 0; i < page_count; i++) {
 191                 vm_page_initfake(&fp[i], start + PAGE_SIZE * i, memattr);
 192                 fp[i].flags &= ~PG_UNMANAGED;
 193                 atomic_clear_int(&fp[i].busy_count, PBUSY_LOCKED);
 194         }
 195         mtx_lock(&vm_phys_fictitious_reg_mtx);
 196         for (segind = 0; segind < VM_PHYS_FICTITIOUS_NSEGS; segind++) {
 197                 seg = &vm_phys_fictitious_segs[segind];
 198                 if (seg->start == 0 && seg->end == 0) {
 199                         seg->start = start;
 200                         seg->end = end;
 201                         seg->first_page = fp;
 202                         mtx_unlock(&vm_phys_fictitious_reg_mtx);
 203                         return (0);
 204                 }
 205         }
 206         mtx_unlock(&vm_phys_fictitious_reg_mtx);
 207         kfree(fp);
 208         return (EBUSY);
 209 }
 210
 211 void
 212 vm_phys_fictitious_unreg_range(vm_paddr_t start, vm_paddr_t end)
 213 {
 214         struct vm_phys_fictitious_seg *seg;
 215         vm_page_t fp;
 216         int segind;
 217
 218         mtx_lock(&vm_phys_fictitious_reg_mtx);
 219         for (segind = 0; segind < VM_PHYS_FICTITIOUS_NSEGS; segind++) {
 220                 seg = &vm_phys_fictitious_segs[segind];
 221                 if (seg->start == start && seg->end == end) {
 222                         seg->start = seg->end = 0;
 223                         fp = seg->first_page;
 224                         seg->first_page = NULL;
 225                         mtx_unlock(&vm_phys_fictitious_reg_mtx);
 226                         kfree(fp);
 227                         return;
 228                 }
 229         }
 230         mtx_unlock(&vm_phys_fictitious_reg_mtx);
 231         KASSERT(0, ("Unregistering not registered fictitious range"));
 232 }