int ttm_bo_mmap_single(struct ttm_bo_device *bdev, vm_ooffset_t *offset, vm_size_t size, struct vm_object **obj_res, int nprot) { struct ttm_bo_driver *driver; struct ttm_buffer_object *bo; struct vm_object *vm_obj; int ret; *obj_res = NULL; lockmgr(&bdev->vm_lock, LK_EXCLUSIVE); bo = ttm_bo_vm_lookup_rb(bdev, OFF_TO_IDX(*offset), OFF_TO_IDX(size)); if (likely(bo != NULL)) kref_get(&bo->kref); lockmgr(&bdev->vm_lock, LK_RELEASE); if (unlikely(bo == NULL)) { kprintf("[TTM] Could not find buffer object to map\n"); return (EINVAL); } driver = bo->bdev->driver; if (unlikely(!driver->verify_access)) { ret = EPERM; goto out_unref; } ret = -driver->verify_access(bo); if (unlikely(ret != 0)) goto out_unref; vm_obj = cdev_pager_allocate(bo, OBJT_MGTDEVICE, &ttm_pager_ops, size, nprot, 0, curthread->td_ucred); if (vm_obj == NULL) { ret = EINVAL; goto out_unref; } /* * Note: We're transferring the bo reference to vm_obj->handle here. */ *offset = 0; *obj_res = vm_obj; return 0; out_unref: ttm_bo_unref(&bo); return ret; }
ssize_t ttm_bo_io(struct ttm_bo_device *bdev, struct file *filp, const char __user *wbuf, char __user *rbuf, size_t count, loff_t *f_pos, bool write) { struct ttm_buffer_object *bo; struct ttm_bo_driver *driver; struct ttm_bo_kmap_obj map; unsigned long dev_offset = (*f_pos >> PAGE_SHIFT); unsigned long kmap_offset; unsigned long kmap_end; unsigned long kmap_num; size_t io_size; unsigned int page_offset; char *virtual; int ret; bool no_wait = false; bool dummy; read_lock(&bdev->vm_lock); bo = ttm_bo_vm_lookup_rb(bdev, dev_offset, 1); if (likely(bo != NULL)) ttm_bo_reference(bo); read_unlock(&bdev->vm_lock); if (unlikely(bo == NULL)) return -EFAULT; driver = bo->bdev->driver; if (unlikely(!driver->verify_access)) { ret = -EPERM; goto out_unref; } ret = driver->verify_access(bo, filp); if (unlikely(ret != 0)) goto out_unref; kmap_offset = dev_offset - bo->vm_node->start; if (unlikely(kmap_offset >= bo->num_pages)) { ret = -EFBIG; goto out_unref; } page_offset = *f_pos & ~PAGE_MASK; io_size = bo->num_pages - kmap_offset; io_size = (io_size << PAGE_SHIFT) - page_offset; if (count < io_size) io_size = count; kmap_end = (*f_pos + count - 1) >> PAGE_SHIFT; kmap_num = kmap_end - kmap_offset + 1; ret = ttm_bo_reserve(bo, true, no_wait, false, 0); switch (ret) { case 0: break; case -EBUSY: ret = -EAGAIN; goto out_unref; default: goto out_unref; } ret = ttm_bo_kmap(bo, kmap_offset, kmap_num, &map); if (unlikely(ret != 0)) { ttm_bo_unreserve(bo); goto out_unref; } virtual = ttm_kmap_obj_virtual(&map, &dummy); virtual += page_offset; if (write) ret = copy_from_user(virtual, wbuf, io_size); else