Enhance the Linux emulation layer to make MegaRAID SAS managements tool happy.

Add back in a scheme to emulate old type major/minor numbers via hooks into
stat, linprocfs to return major/minors that Linux app's expect.  Currently
only /dev/null is always registered.  Drivers can register via the Linux
type shim similar to the ioctl shim but by using
linux_device_register_handler/linux_device_unregister_handler functions.
The structure is:

    struct linux_device_handler {
        char    *bsd_driver_name;
        char    *linux_driver_name;
        char    *bsd_device_name;
        char    *linux_device_name;
        int     linux_major;
        int     linux_minor;
        int     linux_char_device;
    };

Linprocfs uses this to display the major number of the driver.  The
soon to be available linsysfs will use it to fill in the driver name.
Linux_stat uses it to translate the major/minor into Linux type values.

Note major numbers are dynamically assigned via passing in a -1 for
the major number so we don't need to keep track of them.

This is somewhat needed due to us switching to our devfs.  MegaCli
will not run until I add in the linsysfs and mfi Linux compat changes.

Sponsored by:	IronPort Systems

1 files changed, 17 insertions, 0 deletions

diff --git a/sys/compat/linux/linux_util.h b/sys/compat/linux/linux_util.h
index 49a535d..b2711f8 100644
--- a/sys/compat/linux/linux_util.h
+++ b/sys/compat/linux/linux_util.h
@@ -110,4 +110,21 @@ struct __hack
 void linux_msg(const struct thread *td, const char *fmt, ...)
 	__printflike(2, 3);
 
+struct linux_device_handler {
+	char	*bsd_driver_name;
+	char	*linux_driver_name;
+	char	*bsd_device_name;
+	char	*linux_device_name;
+	int	linux_major;
+	int	linux_minor;
+	int	linux_char_device;
+};
+
+int	linux_device_register_handler(struct linux_device_handler *h);
+int	linux_device_unregister_handler(struct linux_device_handler *h);
+char	*linux_driver_get_name_dev(device_t dev);
+int	linux_driver_get_major_minor(char *node, int *major, int *minor);
+char	*linux_get_char_devices(void);
+void	linux_free_get_char_devices(char *string);
+
 #endif /* !_LINUX_UTIL_H_ */