#include "internal.h"
-/*
- * capabilities for /dev/mem, /dev/kmem and similar directly mappable character
- * devices
- * - permits shared-mmap for read, write and/or exec
- * - does not permit private mmap in NOMMU mode (can't do COW)
- * - no readahead or I/O queue unplugging required
- */
-struct backing_dev_info directly_mappable_cdev_bdi = {
- .name = "char",
- .capabilities = (
-#ifdef CONFIG_MMU
- /* permit private copies of the data to be taken */
- BDI_CAP_MAP_COPY |
-#endif
- /* permit direct mmap, for read, write or exec */
- BDI_CAP_MAP_DIRECT |
- BDI_CAP_READ_MAP | BDI_CAP_WRITE_MAP | BDI_CAP_EXEC_MAP |
- /* no writeback happens */
- BDI_CAP_NO_ACCT_AND_WRITEBACK),
-};
-
static struct kobj_map *cdev_map;
static DEFINE_MUTEX(chrdevs_lock);
void __init chrdev_init(void)
{
cdev_map = kobj_map_init(base_probe, &chrdevs_lock);
- if (bdi_init(&directly_mappable_cdev_bdi))
- panic("Failed to init directly mappable cdev bdi");
}
EXPORT_SYMBOL(cdev_add);
EXPORT_SYMBOL(__register_chrdev);
EXPORT_SYMBOL(__unregister_chrdev);
-EXPORT_SYMBOL(directly_mappable_cdev_bdi);