minix/servers/vfs/dmap.c
2011-07-27 12:23:03 +00:00

262 lines
6.8 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 <minix/ds.h>
#include "param.h"
#define NC(x) (NR_CTRLRS >= (x))
/* The order of the entries in the table determines the mapping between major
* device numbers and device drivers. Character and block devices
* can be intermixed at random. The ordering determines the device numbers in
* /dev. Note that the major device numbers used in /dev are NOT the same as
* the process numbers of the device drivers. See <minix/dmap.h> for mappings.
*/
struct dmap dmap[NR_DEVICES];
#define DT_EMPTY { no_dev, no_dev_io, NONE, "", 0, STYLE_NDEV, NULL }
/*===========================================================================*
* do_mapdriver *
*===========================================================================*/
PUBLIC int do_mapdriver()
{
int r, flags, major;
endpoint_t endpoint;
vir_bytes label_vir;
size_t label_len;
char label[LABEL_MAX];
/* Only RS can map drivers. */
if (who_e != RS_PROC_NR)
{
printf("vfs: unauthorized call of do_mapdriver by proc %d\n",
who_e);
return(EPERM);
}
/* Get the label */
label_vir= (vir_bytes)m_in.md_label;
label_len= m_in.md_label_len;
if (label_len+1 > sizeof(label))
{
printf("vfs:do_mapdriver: label too long\n");
return EINVAL;
}
r= sys_vircopy(who_e, D, label_vir, SELF, D, (vir_bytes)label,
label_len);
if (r != OK)
{
printf("vfs:do_mapdriver: sys_vircopy failed: %d\n", r);
return EINVAL;
}
label[label_len]= '\0';
r= ds_retrieve_label_endpt(label, &endpoint);
if (r != OK)
{
printf("vfs:do_mapdriver: ds doesn't know '%s'\n", label);
return EINVAL;
}
/* Try to update device mapping. */
major= m_in.md_major;
flags= m_in.md_flags;
r= map_driver(label, major, endpoint, m_in.md_style, flags);
return(r);
}
/*===========================================================================*
* map_driver *
*===========================================================================*/
PUBLIC int map_driver(label, major, proc_nr_e, style, flags)
const char *label; /* name of the driver */
int major; /* major number of the device */
endpoint_t proc_nr_e; /* process number of the driver */
int style; /* style of the device */
int flags; /* device flags */
{
/* Set a new device driver mapping in the dmap table.
* If the proc_nr is set to NONE, we're supposed to unmap it.
*/
int proc_nr_n;
size_t len;
struct dmap *dp;
/* Get pointer to device entry in the dmap table. */
if (major < 0 || major >= NR_DEVICES) return(ENODEV);
dp = &dmap[major];
/* Check if we're supposed to unmap it. */
if(proc_nr_e == NONE) {
dp->dmap_opcl = no_dev;
dp->dmap_io = no_dev_io;
dp->dmap_driver = NONE;
dp->dmap_flags = flags;
return(OK);
}
/* Check process number of new driver if requested. */
if (! (flags & DRV_FORCED))
{
if (isokendpt(proc_nr_e, &proc_nr_n) != OK)
return(EINVAL);
}
if (label != NULL) {
len= strlen(label);
if (len+1 > sizeof(dp->dmap_label))
panic("map_driver: label too long: %d", len);
strcpy(dp->dmap_label, label);
}
/* Try to update the entry. */
switch (style) {
case STYLE_DEV:
dp->dmap_opcl = gen_opcl;
dp->dmap_io = gen_io;
break;
case STYLE_DEVA:
dp->dmap_opcl = gen_opcl;
dp->dmap_io = asyn_io;
break;
case STYLE_TTY:
dp->dmap_opcl = tty_opcl;
dp->dmap_io = gen_io;
break;
case STYLE_CTTY:
dp->dmap_opcl = ctty_opcl;
dp->dmap_io = ctty_io;
break;
case STYLE_CLONE:
case STYLE_CLONE_A:
dp->dmap_opcl = clone_opcl;
dp->dmap_io = gen_io;
break;
default:
return(EINVAL);
}
dp->dmap_driver = proc_nr_e;
dp->dmap_flags = flags;
dp->dmap_style = style;
return(OK);
}
/*===========================================================================*
* dmap_unmap_by_endpt *
*===========================================================================*/
PUBLIC void dmap_unmap_by_endpt(int proc_nr_e)
{
int i, r;
for (i=0; i<NR_DEVICES; i++)
if(dmap[i].dmap_driver && dmap[i].dmap_driver == proc_nr_e)
if((r=map_driver(NULL, i, NONE, 0, 0)) != OK)
printf("FS: unmap of p %d / d %d failed: %d\n", proc_nr_e,i,r);
return;
}
/*===========================================================================*
* map_service *
*===========================================================================*/
PUBLIC int map_service(struct rprocpub *rpub)
{
/* Map a new service by storing its device driver properties. */
int r;
/* Not a driver, nothing more to do. */
if(!rpub->dev_nr) {
return OK;
}
/* Map driver. */
r = map_driver(rpub->label, rpub->dev_nr, rpub->endpoint,
rpub->dev_style, rpub->dev_flags);
if(r != OK) {
return r;
}
/* If driver has two major numbers associated, also map the other one. */
if(rpub->dev_style2 != STYLE_NDEV) {
r = map_driver(rpub->label, rpub->dev_nr+1, rpub->endpoint,
rpub->dev_style2, rpub->dev_flags);
if(r != OK) {
return r;
}
}
return OK;
}
/*===========================================================================*
* build_dmap *
*===========================================================================*/
PUBLIC void build_dmap()
{
/* Initialize the table with empty device <-> driver mappings. */
int i;
struct dmap dmap_default = DT_EMPTY;
for (i=0; i<NR_DEVICES; i++) {
dmap[i] = dmap_default;
}
}
/*===========================================================================*
* dmap_driver_match *
*===========================================================================*/
PUBLIC int dmap_driver_match(endpoint_t proc, int major)
{
if (major < 0 || major >= NR_DEVICES) return(0);
if(dmap[major].dmap_driver != NONE && dmap[major].dmap_driver == proc)
return 1;
return 0;
}
/*===========================================================================*
* dmap_endpt_up *
*===========================================================================*/
PUBLIC void dmap_endpt_up(int proc_e)
{
int i;
for (i=0; i<NR_DEVICES; i++) {
if(dmap[i].dmap_driver != NONE
&& dmap[i].dmap_driver == proc_e) {
dev_up(i);
}
}
return;
}
/*===========================================================================*
* get_dmap *
*===========================================================================*/
PUBLIC struct dmap *get_dmap(endpoint_t proc_e)
{
/* See if 'proc_e' endpoint belongs to a valid dmap entry. If so, return a
* pointer */
int major;
for (major = 0; major < NR_DEVICES; major++)
if (dmap_driver_match(proc_e, major))
return(&dmap[major]);
return(NULL);
}