[Bluetooth] Integrate services into the driver model

[pandora-kernel.git] / fs / char_dev.c

diff --git a/fs/char_dev.c b/fs/char_dev.c
index a4cbc67..0009346 100644 (file)
--- a/fs/char_dev.c
+++ b/fs/char_dev.c
@@ -19,11 +19,30 @@
 #include <linux/kobj_map.h>
 #include <linux/cdev.h>
 #include <linux/mutex.h>
+#include <linux/backing-dev.h>
 
 #ifdef CONFIG_KMOD
 #include <linux/kmod.h>
 #endif
 
+/*
+ * 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 = {
+       .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),
+};
+
 static struct kobj_map *cdev_map;
 
 static DEFINE_MUTEX(chrdevs_lock);
@@ -182,6 +201,28 @@ int alloc_chrdev_region(dev_t *dev, unsigned baseminor, unsigned count,
        return 0;
 }
 
+/**
+ * register_chrdev() - Register a major number for character devices.
+ * @major: major device number or 0 for dynamic allocation
+ * @name: name of this range of devices
+ * @fops: file operations associated with this devices
+ *
+ * If @major == 0 this functions will dynamically allocate a major and return
+ * its number.
+ *
+ * If @major > 0 this function will attempt to reserve a device with the given
+ * major number and will return zero on success.
+ *
+ * Returns a -ve errno on failure.
+ *
+ * The name of this device has nothing to do with the name of the device in
+ * /dev. It only helps to keep track of the different owners of devices. If
+ * your module name has only one type of devices it's ok to use e.g. the name
+ * of the module here.
+ *
+ * This function registers a range of 256 minor numbers. The first minor number
+ * is 0.
+ */
 int register_chrdev(unsigned int major, const char *name,
                    const struct file_operations *fops)
 {
@@ -439,3 +480,4 @@ EXPORT_SYMBOL(cdev_del);
 EXPORT_SYMBOL(cdev_add);
 EXPORT_SYMBOL(register_chrdev);
 EXPORT_SYMBOL(unregister_chrdev);
+EXPORT_SYMBOL(directly_mappable_cdev_bdi);