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