minix/lib/other/_mount.c
Thomas Veerman b47483433c Added a hack to start binaries from the boot image only. In particular, setting
bin_img=1 in the boot monitor will make sure that during the boot procedure the
mfs binary that is part of the boot image is the only binary that is used to
mount partitions. This is useful when for some reason the mfs binary on disk 
malfunctions, rendering Minix unable to boot. By setting bin_img=1, the binary
on disk is ignored and the binary in the boot image is used instead.

- 'service' now accepts an additional flag -r. -r implies -c. -r instructs RS
  to first look in memory if the binary has already been copied to memory and
  execute that version, instead of loading the binary from disk. For example,
  the first time a MFS is being started it is copied (-c) to memory and
  executed from there. The second time MFS is being started this way, RS will
  look in memory for a previously copied MFS binary and reuse it if it exists.
- The mount and newroot commands now accept an additional flag -i, which
  instructs them to set the MS_REUSE flag in the mount flags.
- The mount system call now supports the MS_REUSE flag and invokes 'service'
  with the -r flag when MS_REUSE is set.
- /etc/rc and the rc script that's included in the boot image check for the
  existence of the bin_img flag in the boot monitor, and invoke mount and 
  newroot with the -i flag accordingly.
2009-08-18 11:36:01 +00:00

163 lines
3.1 KiB
C
Executable file

#include <lib.h>
#define mount _mount
#define umount _umount
#include <string.h>
#include <sys/mount.h>
#include <stdlib.h>
#include <stdio.h>
#include <sys/stat.h>
#include <minix/syslib.h>
#include <minix/rs.h>
#include <minix/paths.h>
#define OK 0
#define FSPATH "/sbin/"
#define FSDEFAULT "mfs"
PRIVATE int rs_down(char *label)
{
char cmd[200];
message m;
if(strlen(_PATH_SERVICE)+strlen(label)+50 >= sizeof(cmd))
return -1;
sprintf(cmd, _PATH_SERVICE " down '%s'", label);
return system(cmd);
}
PRIVATE char *makelabel(_CONST char *special)
{
static char label[40];
_CONST char *dev;
/* Make label name. */
dev = strrchr(special, '/');
if(dev) dev++;
else dev = special;
if(strchr(dev, '\'') != NULL) {
errno = EINVAL;
return NULL;
}
if(strlen(dev)+4 >= sizeof(label)) {
errno = E2BIG;
return NULL;
}
sprintf(label, "fs_%s", dev);
return label;
}
PUBLIC int mount(special, name, mountflags, type, args)
char *name, *special, *type, *args;
int mountflags;
{
int r;
message m;
struct rs_start rs_start;
struct stat statbuf;
char *label;
char path[60];
char cmd[200];
FILE *pipe;
int ep;
int reuse;
/* Default values. */
if (type == NULL) type = FSDEFAULT;
if (args == NULL) args = "";
reuse = 0;
/* Check mount flags */
if(mountflags & MS_REUSE) {
reuse = 1;
mountflags &= ~MS_REUSE; /* Temporary: turn off to not confuse VFS */
}
/* Make FS process label for RS from special name. */
if(!(label=makelabel(special))) {
return -1;
}
/* See if the given type is even remotely valid. */
if(strlen(FSPATH)+strlen(type) >= sizeof(path)) {
errno = E2BIG;
return -1;
}
strcpy(path, FSPATH);
strcat(path, type);
if(stat(path, &statbuf) != 0) {
errno = EINVAL;
return -1;
}
/* Sanity check on user input. */
if(strchr(args, '\'')) {
errno = EINVAL;
return -1;
}
if(strlen(_PATH_SERVICE)+strlen(path)+strlen(label)+
strlen(_PATH_DRIVERS_CONF)+strlen(args)+50 >= sizeof(cmd)) {
errno = E2BIG;
return -1;
}
sprintf(cmd, _PATH_SERVICE " %sup %s -label '%s' -config " _PATH_DRIVERS_CONF
" -args '%s%s' -printep yes",
reuse ? "-r ": "", path, label, args[0] ? "-o " : "", args);
if(!(pipe = popen(cmd, "r"))) {
fprintf(stderr, "mount: couldn't run %s\n", cmd);
return -1;
}
if(fscanf(pipe, "%d", &ep) != 1 || ep <= 0) {
fprintf(stderr, "mount: couldn't parse endpoint from %s\n", cmd);
errno = EINVAL;
pclose(pipe);
return -1;
}
pclose(pipe);
/* Now perform mount(). */
m.m1_i1 = strlen(special) + 1;
m.m1_i2 = strlen(name) + 1;
m.m1_i3 = mountflags;
m.m1_p1 = special;
m.m1_p2 = name;
m.m1_p3 = (char*) ep;
r = _syscall(FS, MOUNT, &m);
if(r != OK) {
/* If mount() failed, tell RS to shutdown MFS process.
* No error check - won't do anything with this error anyway.
*/
rs_down(label);
}
return r;
}
PUBLIC int umount(name)
_CONST char *name;
{
message m;
char *label;
int r;
/* Make MFS process label for RS from special name. */
if(!(label=makelabel(name))) {
return -1;
}
_loadname(name, &m);
r = _syscall(FS, UMOUNT, &m);
if(r == OK) {
rs_down(label);
}
return r;
}