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/*
* srm_env.c - Access to SRC environment variables through
* the linux procfs
*
* (C)2001, Jan-Benedict Glaw <jbglaw@lug-owl.de>
*
* This driver is at all a modified version of Erik Mouw's
* ./linux/Documentation/DocBook/procfs_example.c, so: thanky
* you, Erik! He can be reached via email at
* <J.A.K.Mouw@its.tudelft.nl>. It is based on an idea
* provided by DEC^WCompaq's "Jumpstart" CD. They included
* a patch like this as well. Thanks for idea!
*
*
* This software has been developed while working on the LART
* computing board (http://www.lart.tudelft.nl/). The
* development has been sponsored by the Mobile Multi-media
* Communications (http://www.mmc.tudelft.nl/) and Ubiquitous
* Communications (http://www.ubicom.tudelft.nl/) projects.
*
* This program is free software; you can redistribute
* it and/or modify it under the terms of the GNU General
* Public License as published by the Free Software
* Foundation version 2.
*
* This program is distributed in the hope that it will be
* useful, but WITHOUT ANY WARRANTY; without even the implied
* warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR
* PURPOSE. See the GNU General Public License for more
* details.
*
* You should have received a copy of the GNU General Public
* License along with this program; if not, write to the
* Free Software Foundation, Inc., 59 Temple Place,
* Suite 330, Boston, MA 02111-1307 USA
*
*/
#include <linux/kernel.h>
#include <linux/config.h>
#include <linux/module.h>
#include <linux/init.h>
#include <linux/proc_fs.h>
#include <asm/console.h>
#include <asm/uaccess.h>
#define DIRNAME "srm_environment" /* Subdir in /proc/ */
#define VERSION "0.0.2" /* Module version */
#define NAME "srm_env" /* Module name */
#define DEBUG
MODULE_AUTHOR("Jan-Benedict Glaw <jbglaw@lug-owl.de>");
MODULE_DESCRIPTION("Accessing Alpha SRM environment through procfs interface");
MODULE_LICENSE("GPL");
EXPORT_NO_SYMBOLS;
typedef struct _srm_env {
char *name;
unsigned long id;
struct proc_dir_entry *proc_entry;
} srm_env_t;
static struct proc_dir_entry *directory;
static srm_env_t srm_entries[] = {
{ "auto_action", ENV_AUTO_ACTION },
{ "boot_dev", ENV_BOOT_DEV },
{ "bootdef_dev", ENV_BOOTDEF_DEV },
{ "booted_dev", ENV_BOOTED_DEV },
{ "boot_file", ENV_BOOT_FILE },
{ "booted_file", ENV_BOOTED_FILE },
{ "boot_osflags", ENV_BOOT_OSFLAGS },
{ "booted_osflags", ENV_BOOTED_OSFLAGS },
{ "boot_reset", ENV_BOOT_RESET },
{ "dump_dev", ENV_DUMP_DEV },
{ "enable_audit", ENV_ENABLE_AUDIT },
{ "license", ENV_LICENSE },
{ "char_set", ENV_CHAR_SET },
{ "language", ENV_LANGUAGE },
{ "tty_dev", ENV_TTY_DEV },
{ NULL, 0 },
};
static int srm_env_read(char *page, char **start, off_t off, int count,
int *eof, void *data)
{
int nbytes;
unsigned long ret;
srm_env_t *entry;
MOD_INC_USE_COUNT;
if(off != 0) {
MOD_DEC_USE_COUNT;
return -EFAULT;
}
entry = (srm_env_t *)data;
ret = callback_getenv(entry->id, page, count);
if((ret >> 61) == 0)
nbytes = (int)ret;
else
nbytes = -EFAULT;
MOD_DEC_USE_COUNT;
return nbytes;
}
static int srm_env_write(struct file *file, const char *buffer,
unsigned long count, void *data)
{
#define BUFLEN 512
int nbytes;
srm_env_t *entry;
char buf[BUFLEN];
unsigned long ret1, ret2;
MOD_INC_USE_COUNT;
entry = (srm_env_t *) data;
nbytes = strlen(buffer) + 1;
if(nbytes > BUFLEN) {
MOD_DEC_USE_COUNT;
return -ENOMEM;
}
//memcpy(aligned_buffer, buffer, nbytes)
if(copy_from_user(buf, buffer, count)) {
MOD_DEC_USE_COUNT;
return -EFAULT;
}
buf[count] = 0x00;
ret1 = callback_setenv(entry->id, buf, count);
if((ret1 >> 61) == 0) {
do
ret2 = callback_save_env();
while((ret2 >> 61) == 1);
nbytes = (int)ret1;
} else
nbytes = -EFAULT;
MOD_DEC_USE_COUNT;
return nbytes;
}
static void srm_env_cleanup(void)
{
srm_env_t *entry;
if(directory) {
entry = srm_entries;
while(entry->name != NULL && entry->id != 0) {
if(entry->proc_entry) {
remove_proc_entry(entry->name, directory);
entry->proc_entry = NULL;
}
entry++;
}
remove_proc_entry(DIRNAME, NULL);
}
return;
}
static int __init srm_env_init(void)
{
srm_env_t *entry;
if(!alpha_using_srm) {
printk(KERN_INFO "%s: This Alpha system doesn't "
"know about SRM...\n", __FUNCTION__);
return -ENODEV;
}
directory = proc_mkdir(DIRNAME, NULL);
if(directory == NULL)
return -ENOMEM;
directory->owner = THIS_MODULE;
/* Now create all the nodes... */
entry = srm_entries;
while(entry->name != NULL && entry->id != 0) {
entry->proc_entry = create_proc_entry(entry->name, 0644,
directory);
if(entry->proc_entry == NULL)
goto cleanup;
entry->proc_entry->data = entry;
entry->proc_entry->read_proc = srm_env_read;
entry->proc_entry->write_proc = srm_env_write;
entry->proc_entry->owner = THIS_MODULE;
entry++;
}
printk(KERN_INFO "%s: version %s loaded successfully\n", NAME,
VERSION);
return 0;
cleanup:
srm_env_cleanup();
return -ENOMEM;
}
static void __exit srm_env_exit(void)
{
srm_env_cleanup();
printk(KERN_INFO "%s: unloaded successfully\n", NAME);
return;
}
module_init(srm_env_init);
module_exit(srm_env_exit);
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