minix/servers/fs/dmap.c
2005-08-05 16:21:32 +00:00

167 lines
6.3 KiB
C

/* This file contains the table with device <-> driver mappings. It also
* contains some routines to dynamically add and/ or remove device drivers
* or change mappings.
*/
#include "fs.h"
#include "fproc.h"
#include <string.h>
#include <stdlib.h>
#include <ctype.h>
#include <unistd.h>
#include <minix/com.h>
#include "param.h"
/* Some devices may or may not be there in the next table. */
#define DT(enable, opcl, io, driver, flags) \
{ (enable?(opcl):no_dev), (enable?(io):0), \
(enable?(driver):0), (flags) },
#define NC(x) (NR_CTRLRS >= (x))
/* The order of the entries here determines the mapping between major device
* numbers and tasks. The first entry (major device 0) is not used. The
* next entry is major device 1, etc. Character and block devices can be
* intermixed at random. The ordering determines the device numbers in /dev/.
* Note that FS knows the device number of /dev/ram/ to load the RAM disk.
* Also note that the major device numbers used in /dev/ are NOT the same as
* the process numbers of the device drivers.
*/
/*
Driver enabled Open/Cls I/O Driver # Flags Device File
-------------- -------- ------ ----------- ----- ------ ----
*/
struct dmap dmap[NR_DEVICES] = {
DT(1, no_dev, 0, 0, 0) /* 0 = not used */
DT(1, gen_opcl, gen_io, MEM_PROC_NR, 0) /* 1 = /dev/mem */
DT(0, gen_opcl, gen_io, NONE, DMAP_MUTABLE) /* 2 = /dev/fd0 */
DT(NC(1), gen_opcl, gen_io, CTRLR(0), DMAP_MUTABLE) /* 3 = /dev/c0 */
DT(1, tty_opcl, gen_io, TTY_PROC_NR, 0) /* 4 = /dev/tty00 */
DT(1, ctty_opcl,ctty_io,TTY_PROC_NR, 0) /* 5 = /dev/tty */
DT(0, gen_opcl, gen_io, NONE, DMAP_MUTABLE) /* 6 = /dev/lp */
#if (MACHINE == IBM_PC)
DT(1, no_dev, 0, 0, DMAP_MUTABLE) /* 7 = /dev/ip */
DT(NC(2), gen_opcl, gen_io, CTRLR(1), DMAP_MUTABLE) /* 8 = /dev/c1 */
DT(0, 0, 0, 0, DMAP_MUTABLE) /* 9 = not used */
DT(NC(3), gen_opcl, gen_io, CTRLR(2), DMAP_MUTABLE) /*10 = /dev/c2 */
DT(0, 0, 0, 0, DMAP_MUTABLE) /*11 = not used */
DT(NC(4), gen_opcl, gen_io, CTRLR(3), DMAP_MUTABLE) /*12 = /dev/c3 */
DT(0, gen_opcl, gen_io, NONE, DMAP_MUTABLE) /*13 = /dev/audio */
DT(0, gen_opcl, gen_io, NONE, DMAP_MUTABLE) /*14 = /dev/mixer */
DT(1, gen_opcl, gen_io, LOG_PROC_NR, 0) /*15 = /dev/klog */
DT(0, gen_opcl, gen_io, NONE, DMAP_MUTABLE) /*16 = /dev/random */
DT(0, gen_opcl, gen_io, NONE, DMAP_MUTABLE) /*17 = /dev/cmos */
#endif /* IBM_PC */
};
/*===========================================================================*
* do_devctl *
*===========================================================================*/
PUBLIC int do_devctl()
{
int result;
switch(m_in.ctl_req) {
case DEV_MAP:
/* Try to update device mapping. */
result = map_driver(m_in.dev_nr, m_in.driver_nr, m_in.dev_style);
break;
case DEV_UNMAP:
result = ENOSYS;
break;
default:
result = EINVAL;
}
return(result);
}
/*===========================================================================*
* map_driver *
*===========================================================================*/
PUBLIC int map_driver(major, proc_nr, style)
int major; /* major number of the device */
int proc_nr; /* process number of the driver */
int style; /* style of the device */
{
/* Set a new device driver mapping in the dmap table. Given that correct
* arguments are given, this only works if the entry is mutable and the
* current driver is not busy.
* Normal error codes are returned so that this function can be used from
* a system call that tries to dynamically install a new driver.
*/
struct dmap *dp;
/* Get pointer to device entry in the dmap table. */
if (major >= NR_DEVICES) return(ENODEV);
dp = &dmap[major];
/* See if updating the entry is allowed. */
if (! (dp->dmap_flags & DMAP_MUTABLE)) return(EPERM);
if (dp->dmap_flags & DMAP_BUSY) return(EBUSY);
/* Check process number of new driver. */
if (! isokprocnr(proc_nr)) return(EINVAL);
/* Try to update the entry. */
switch (style) {
case STYLE_DEV: dp->dmap_opcl = gen_opcl; break;
case STYLE_TTY: dp->dmap_opcl = tty_opcl; break;
case STYLE_CLONE: dp->dmap_opcl = clone_opcl; break;
default: return(EINVAL);
}
dp->dmap_io = gen_io;
dp->dmap_driver = proc_nr;
return(OK);
}
/*===========================================================================*
* map_controller *
*===========================================================================*/
PUBLIC void map_controller()
{
/* Map the boot driver to a controller and update the dmap table to that
* selection. The boot driver and the controller it handles are set at the
* boot monitor.
*/
char driver[16];
char *controller = "c##";
int nr, major = -1;
int i,s;
/* Get settings of 'controller' and 'driver' at the boot monitor. */
if ((s = env_get_param("label", driver, sizeof(driver))) != OK)
panic(__FILE__,"couldn't get boot monitor parameter 'driver'", s);
if ((s = env_get_param("controller", controller, sizeof(controller))) != OK)
panic(__FILE__,"couldn't get boot monitor parameter 'controller'", s);
/* Determine major number to map driver onto. */
if (controller[0] == 'f' && controller[1] == 'd') {
major = FLOPPY_MAJOR;
}
else if (controller[0] == 'c' && isdigit(controller[1])) {
if ((nr = (unsigned) atoi(&controller[1])) > NR_CTRLRS)
panic(__FILE__,"monitor 'controller' maximum 'c#' is", NR_CTRLRS);
for (i=0; i< NR_DEVICES; i++) { /* find controller */
if (dmap[i].dmap_driver == CTRLR(nr)) {
major = i;
break;
}
}
if ((unsigned) major >= NR_DEVICES)
panic(__FILE__, "cannot find controller in dmap, number", nr);
}
else {
panic(__FILE__,"monitor 'controller' syntax is 'c#' of 'fd'", NO_NUM);
}
/* Now try to set the actual mapping and report to the user. */
if ((s=map_driver(i, DRVR_PROC_NR, STYLE_DEV)) != OK)
panic(__FILE__,"map_driver failed",s);
printf("Boot medium driver: %s driver mapped onto controller %s.\n",
driver, controller);
}