drm: bring bufs code from git tree.

This checks the AGP mappings are in a valid place and also fixes the size
check in the vm..

Signed-off-by: Dave Airlie <airlied@linux.ie>

2 files changed, 67 insertions, 10 deletions

diff --git a/drivers/char/drm/drm_bufs.c b/drivers/char/drm/drm_bufs.c
index a6828cc14e58..c11345856ffe 100644
--- a/drivers/char/drm/drm_bufs.c
+++ b/drivers/char/drm/drm_bufs.c
@@ -57,7 +57,8 @@ static drm_map_list_t *drm_find_matching_map(drm_device_t *dev,
         list_for_each(list, &dev->maplist->head) {
                 drm_map_list_t *entry = list_entry(list, drm_map_list_t, head);
                 if (entry->map && map->type == entry->map->type &&
-                    entry->map->offset == map->offset) {
+                    ((entry->map->offset == map->offset) ||
+                     (map->type == _DRM_SHM && map->flags==_DRM_CONTAINS_LOCK))) {
                         return entry;
                 }
         }
@@ -180,8 +181,20 @@ static int drm_addmap_core(drm_device_t * dev, unsigned int offset,
                 if (map->type == _DRM_REGISTERS)
                         map->handle = ioremap(map->offset, map->size);
                 break;
-
         case _DRM_SHM:
+                list = drm_find_matching_map(dev, map);
+                if (list != NULL) {
+                        if(list->map->size != map->size) {
+                                DRM_DEBUG("Matching maps of type %d with "
+                                          "mismatched sizes, (%ld vs %ld)\n",
+                                          map->type, map->size, list->map->size);
+                                list->map->size = map->size;
+                        }
+
+                        drm_free(map, sizeof(*map), DRM_MEM_MAPS);
+                        *maplist = list;
+                        return 0;
+                }
                 map->handle = vmalloc_user(map->size);
                 DRM_DEBUG("%lu %d %p\n",
                           map->size, drm_order(map->size), map->handle);
@@ -200,15 +213,45 @@ static int drm_addmap_core(drm_device_t * dev, unsigned int offset,
                         dev->sigdata.lock = dev->lock.hw_lock = map->handle;    /* Pointer to lock */
                 }
                 break;
-        case _DRM_AGP:
-                if (drm_core_has_AGP(dev)) {
+        case _DRM_AGP: {
+                drm_agp_mem_t *entry;
+                int valid = 0;
+
+                if (!drm_core_has_AGP(dev)) {
+                        drm_free(map, sizeof(*map), DRM_MEM_MAPS);
+                        return -EINVAL;
+                }
 #ifdef __alpha__
-                        map->offset += dev->hose->mem_space->start;
+                map->offset += dev->hose->mem_space->start;
 #endif
-                        map->offset += dev->agp->base;
-                        map->mtrr = dev->agp->agp_mtrr; /* for getmap */
+                /* Note: dev->agp->base may actually be 0 when the DRM
+                 * is not in control of AGP space. But if user space is
+                 * it should already have added the AGP base itself.
+                 */
+                map->offset += dev->agp->base;
+                map->mtrr = dev->agp->agp_mtrr; /* for getmap */
+
+                /* This assumes the DRM is in total control of AGP space.
+                 * It's not always the case as AGP can be in the control
+                 * of user space (i.e. i810 driver). So this loop will get
+                 * skipped and we double check that dev->agp->memory is
+                 * actually set as well as being invalid before EPERM'ing
+                 */
+                for (entry = dev->agp->memory; entry; entry = entry->next) {
+                        if ((map->offset >= entry->bound) &&
+                            (map->offset + map->size <= entry->bound + entry->pages * PAGE_SIZE)) {
+                                valid = 1;
+                                break;
+                        }
                 }
+                if (dev->agp->memory && !valid) {
+                        drm_free(map, sizeof(*map), DRM_MEM_MAPS);
+                        return -EPERM;
+                }
+                DRM_DEBUG("AGP offset = 0x%08lx, size = 0x%08lx\n", map->offset, map->size);
+
                 break;
+        }
         case _DRM_SCATTER_GATHER:
                 if (!dev->sg) {
                         drm_free(map, sizeof(*map), DRM_MEM_MAPS);
@@ -267,7 +310,7 @@ static int drm_addmap_core(drm_device_t * dev, unsigned int offset,
 
         *maplist = list;
         return 0;
-}
+        }
 
 int drm_addmap(drm_device_t * dev, unsigned int offset,
                unsigned int size, drm_map_type_t type,
@@ -519,6 +562,7 @@ int drm_addbufs_agp(drm_device_t * dev, drm_buf_desc_t * request)
 {
         drm_device_dma_t *dma = dev->dma;
         drm_buf_entry_t *entry;
+        drm_agp_mem_t *agp_entry;
         drm_buf_t *buf;
         unsigned long offset;
         unsigned long agp_offset;
@@ -529,7 +573,7 @@ int drm_addbufs_agp(drm_device_t * dev, drm_buf_desc_t * request)
         int page_order;
         int total;
         int byte_count;
-        int i;
+        int i, valid;
         drm_buf_t **temp_buflist;
 
         if (!dma)
@@ -560,6 +604,19 @@ int drm_addbufs_agp(drm_device_t * dev, drm_buf_desc_t * request)
         if (dev->queue_count)
                 return -EBUSY;  /* Not while in use */
 
+        /* Make sure buffers are located in AGP memory that we own */
+        valid = 0;
+        for (agp_entry = dev->agp->memory; agp_entry; agp_entry = agp_entry->next) {
+                if ((agp_offset >= agp_entry->bound) &&
+                    (agp_offset + total * count <= agp_entry->bound + agp_entry->pages * PAGE_SIZE)) {
+                        valid = 1;
+                        break;
+                }
+        }
+        if (dev->agp->memory && !valid) {
+                DRM_DEBUG("zone invalid\n");
+                return -EINVAL;
+        }
         spin_lock(&dev->count_lock);
         if (dev->buf_use) {
                 spin_unlock(&dev->count_lock);
diff --git a/drivers/char/drm/drm_vm.c b/drivers/char/drm/drm_vm.c
index 7ed77e16488c..9e3f25946590 100644
--- a/drivers/char/drm/drm_vm.c
+++ b/drivers/char/drm/drm_vm.c
@@ -589,7 +589,7 @@ int drm_mmap(struct file *filp, struct vm_area_struct *vma)
                 return -EPERM;
 
         /* Check for valid size. */
-        if (map->size != vma->vm_end - vma->vm_start)
+        if (map->size < vma->vm_end - vma->vm_start)
                 return -EINVAL;
 
         if (!capable(CAP_SYS_ADMIN) && (map->flags & _DRM_READ_ONLY)) {