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 <drm/drmP.h>
  31 #include <linux/export.h>
  32 #include <linux/seq_file.h>
  33 #if defined(__ia64__)
  34 #include <linux/efi.h>
  35 #include <linux/slab.h>
  36 #endif
  37 #include <linux/mem_encrypt.h>
  38 #include <asm/pgtable.h>
  39 #include "drm_internal.h"
  40 #include "drm_legacy.h"
  41
  42 #include <sys/mutex2.h>
  43
  44 int
  45 drm_mmap(struct dev_mmap_args *ap)
  46 {
  47         struct file *filp = ap->a_fp;
  48         struct drm_file *priv;
  49         struct cdev *kdev = ap->a_head.a_dev;
  50         vm_offset_t offset = ap->a_offset;
  51         struct drm_device *dev = drm_get_device_from_kdev(kdev);
  52         struct drm_local_map *map = NULL;
  53         struct drm_hash_item *hash;
  54         enum drm_map_type type;
  55         vm_paddr_t phys;
  56
  57         /*
  58          * NOTE: If ddev->drm_ttm_bdev is not setup properly, this path
  59          *       may be hit with a NULL filp and panic.
  60          */
  61         priv = filp->private_data;
  62         if (!priv->authenticated)
  63                 return -EACCES;
  64
  65         DRM_DEBUG("called with offset %016jx\n", (uintmax_t)offset);
  66         if (dev->dma && offset < ptoa(dev->dma->page_count)) {
  67                 struct drm_device_dma *dma = dev->dma;
  68
  69                 if (dma->pagelist != NULL) {
  70                         unsigned long page = offset >> PAGE_SHIFT;
  71                         unsigned long phys = dma->pagelist[page];
  72
  73                         // XXX *paddr = phys;
  74                         ap->a_result = phys;
  75                         return 0;
  76                 } else {
  77                         return -1;
  78                 }
  79         }
  80
  81         /* A sequential search of a linked list is
  82            fine here because: 1) there will only be
  83            about 5-10 entries in the list and, 2) a
  84            DRI client only has to do this mapping
  85            once, so it doesn't have to be optimized
  86            for performance, even if the list was a
  87            bit longer.
  88         */
  89         DRM_LOCK(dev);
  90
  91         if (drm_ht_find_item(&dev->map_hash, offset, &hash)) {
  92                 DRM_ERROR("Could not find map\n");
  93                 DRM_UNLOCK(dev);
  94                 return -EINVAL;
  95         }
  96
  97         map = drm_hash_entry(hash, struct drm_map_list, hash)->map;
  98         if (map == NULL) {
  99                 DRM_DEBUG("Can't find map, request offset = %016jx\n",
 100                     (uintmax_t)offset);
 101                 DRM_UNLOCK(dev);
 102                 return -1;
 103         }
 104         if (((map->flags & _DRM_RESTRICTED) && !capable(CAP_SYS_ADMIN))) {
 105                 DRM_UNLOCK(dev);
 106                 DRM_DEBUG("restricted map\n");
 107                 return -1;
 108         }
 109
 110         type = map->type;
 111         DRM_UNLOCK(dev);
 112
 113         switch (type) {
 114         case _DRM_FRAME_BUFFER:
 115         case _DRM_AGP:
 116 #if 0   /* XXX */
 117                 *memattr = VM_MEMATTR_WRITE_COMBINING;
 118 #endif
 119                 /* FALLTHROUGH */
 120         case _DRM_REGISTERS:
 121                 phys = map->offset + offset;
 122                 break;
 123         case _DRM_SCATTER_GATHER:
 124 #if 0   /* XXX */
 125                 *memattr = VM_MEMATTR_WRITE_COMBINING;
 126 #endif
 127                 /* FALLTHROUGH */
 128         case _DRM_CONSISTENT:
 129         case _DRM_SHM:
 130                 phys = vtophys((char *)map->handle + offset);
 131                 break;
 132         default:
 133                 DRM_ERROR("bad map type %d\n", type);
 134                 return -1;      /* This should never happen. */
 135         }
 136
 137         ap->a_result = atop(phys);
 138         return 0;
 139 }
 140
 141 /* XXX The following is just temporary hack to replace the
 142  * vm_phys_fictitious functions available on FreeBSD
 143  */
 144 #define VM_PHYS_FICTITIOUS_NSEGS        8
 145 static struct vm_phys_fictitious_seg {
 146         vm_paddr_t      start;
 147         vm_paddr_t      end;
 148         vm_page_t       first_page;
 149 } vm_phys_fictitious_segs[VM_PHYS_FICTITIOUS_NSEGS];
 150 static struct mtx vm_phys_fictitious_reg_mtx = MTX_INITIALIZER("vmphy");
 151
 152 vm_page_t
 153 vm_phys_fictitious_to_vm_page(vm_paddr_t pa)
 154 {
 155         struct vm_phys_fictitious_seg *seg;
 156         vm_page_t m;
 157         int segind;
 158
 159         m = NULL;
 160         for (segind = 0; segind < VM_PHYS_FICTITIOUS_NSEGS; segind++) {
 161                 seg = &vm_phys_fictitious_segs[segind];
 162                 if (pa >= seg->start && pa < seg->end) {
 163                         m = &seg->first_page[atop(pa - seg->start)];
 164                         KASSERT((m->flags & PG_FICTITIOUS) != 0,
 165                             ("%p not fictitious", m));
 166                         break;
 167                 }
 168         }
 169         return (m);
 170 }
 171
 172 int
 173 vm_phys_fictitious_reg_range(vm_paddr_t start, vm_paddr_t end,
 174                              vm_memattr_t memattr)
 175 {
 176         struct vm_phys_fictitious_seg *seg;
 177         vm_page_t fp;
 178         long i, page_count;
 179         int segind;
 180
 181         page_count = (end - start) / PAGE_SIZE;
 182
 183         fp = kmalloc(page_count * sizeof(struct vm_page), M_DRM,
 184                     M_WAITOK | M_ZERO);
 185
 186         for (i = 0; i < page_count; i++) {
 187                 vm_page_initfake(&fp[i], start + PAGE_SIZE * i, memattr);
 188                 atomic_clear_int(&fp[i].busy_count, PBUSY_LOCKED);
 189         }
 190         mtx_lock(&vm_phys_fictitious_reg_mtx);
 191         for (segind = 0; segind < VM_PHYS_FICTITIOUS_NSEGS; segind++) {
 192                 seg = &vm_phys_fictitious_segs[segind];
 193                 if (seg->start == 0 && seg->end == 0) {
 194                         seg->start = start;
 195                         seg->end = end;
 196                         seg->first_page = fp;
 197                         mtx_unlock(&vm_phys_fictitious_reg_mtx);
 198                         return (0);
 199                 }
 200         }
 201         mtx_unlock(&vm_phys_fictitious_reg_mtx);
 202         kfree(fp);
 203         return (EBUSY);
 204 }
 205
 206 void
 207 vm_phys_fictitious_unreg_range(vm_paddr_t start, vm_paddr_t end)
 208 {
 209         struct vm_phys_fictitious_seg *seg;
 210         vm_page_t fp;
 211         int segind;
 212
 213         mtx_lock(&vm_phys_fictitious_reg_mtx);
 214         for (segind = 0; segind < VM_PHYS_FICTITIOUS_NSEGS; segind++) {
 215                 seg = &vm_phys_fictitious_segs[segind];
 216                 if (seg->start == start && seg->end == end) {
 217                         seg->start = seg->end = 0;
 218                         fp = seg->first_page;
 219                         seg->first_page = NULL;
 220                         mtx_unlock(&vm_phys_fictitious_reg_mtx);
 221                         kfree(fp);
 222                         return;
 223                 }
 224         }
 225         mtx_unlock(&vm_phys_fictitious_reg_mtx);
 226         KASSERT(0, ("Unregistering not registered fictitious range"));
 227 }