/* * srm_env.c - Access to SRM environment *             variables through linux' procfs * * (C) 2001,2002,2006 by Jan-Benedict Glaw <jbglaw@lug-owl.de> * * This driver is at all a modified version of Erik Mouw's * Documentation/DocBook/procfs_example.c, so: thank * 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^WIntel's "Jumpstart" CD. They * included a patch like this as well. Thanks for idea! * * This program is free software; you can redistribute * it and/or modify it under the terms of the GNU General * Public License version 2 as published by the Free Software * Foundation. * * 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/module.h>#include <linux/init.h>#include <linux/proc_fs.h>#include <asm/console.h>#include <asm/uaccess.h>#include <asm/machvec.h> #define BASE_DIR	"srm_environment"	/* Subdir in /proc/		*/#define NAMED_DIR	"named_variables"	/* Subdir for known variables	*/#define NUMBERED_DIR	"numbered_variables"	/* Subdir for all variables	*/#define VERSION		"0.0.6"			/* Module version		*/#define NAME		"srm_env"		/* Module name			*/ MODULE_AUTHOR("Jan-Benedict Glaw <jbglaw@lug-owl.de>");MODULE_DESCRIPTION("Accessing Alpha SRM environment through procfs interface");MODULE_LICENSE("GPL"); typedef struct _srm_env {	char			*name;	unsigned long		id;	struct proc_dir_entry	*proc_entry;} srm_env_t; static struct proc_dir_entry	*base_dir;static struct proc_dir_entry	*named_dir;static struct proc_dir_entry	*numbered_dir;static char			number[256][4]; static srm_env_t	srm_named_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 srm_env_t	srm_numbered_entries[256];  static intsrm_env_read(char *page, char **start, off_t off, int count, int *eof,		void *data){	int		nbytes;	unsigned long	ret;	srm_env_t	*entry; 	if (off != 0) {		*eof = 1;		return 0;	} 	entry	= (srm_env_t *) data;	ret	= callback_getenv(entry->id, page, count); 	if ((ret >> 61) == 0) {		nbytes = (int) ret;		*eof = 1;	} else		nbytes = -EFAULT; 	return nbytes;} static intsrm_env_write(struct file *file, const char __user *buffer, unsigned long count,		void *data){	int res;	srm_env_t	*entry;	char		*buf = (char *) __get_free_page(GFP_USER);	unsigned long	ret1, ret2; 	entry = (srm_env_t *) data; 	if (!buf)		return -ENOMEM; 	res = -EINVAL;	if (count >= PAGE_SIZE)		goto out; 	res = -EFAULT;	if (copy_from_user(buf, buffer, count))		goto out;	buf[count] = '\0'; 	ret1 = callback_setenv(entry->id, buf, count);	if ((ret1 >> 61) == 0) {		do			ret2 = callback_save_env();		while((ret2 >> 61) == 1);		res = (int) ret1;	}  out:	free_page((unsigned long)buf);	return res;} static voidsrm_env_cleanup(void){	srm_env_t	*entry;	unsigned long	var_num; 	if (base_dir) {		/*		 * Remove named entries		 */		if (named_dir) {			entry = srm_named_entries;			while (entry->name != NULL && entry->id != 0) {				if (entry->proc_entry) {					remove_proc_entry(entry->name,							named_dir);					entry->proc_entry = NULL;				}				entry++;			}			remove_proc_entry(NAMED_DIR, base_dir);		} 		/*		 * Remove numbered entries		 */		if (numbered_dir) {			for (var_num = 0; var_num <= 255; var_num++) {				entry =	&srm_numbered_entries[var_num]; 				if (entry->proc_entry) {					remove_proc_entry(entry->name,							numbered_dir);					entry->proc_entry	= NULL;					entry->name		= NULL;				}			}			remove_proc_entry(NUMBERED_DIR, base_dir);		} 		remove_proc_entry(BASE_DIR, NULL);	} 	return;} static int __initsrm_env_init(void){	srm_env_t	*entry;	unsigned long	var_num; 	/*	 * Check system	 */	if (!alpha_using_srm) {		printk(KERN_INFO "%s: This Alpha system doesn't "				"know about SRM (or you've booted "				"SRM->MILO->Linux, which gets "				"misdetected)...\n", __FUNCTION__);		return -ENODEV;	} 	/*	 * Init numbers	 */	for (var_num = 0; var_num <= 255; var_num++)		sprintf(number[var_num], "%ld", var_num); 	/*	 * Create base directory	 */	base_dir = proc_mkdir(BASE_DIR, NULL);	if (!base_dir) {		printk(KERN_ERR "Couldn't create base dir /proc/%s\n",				BASE_DIR);		goto cleanup;	}	base_dir->owner = THIS_MODULE; 	/*	 * Create per-name subdirectory	 */	named_dir = proc_mkdir(NAMED_DIR, base_dir);	if (!named_dir) {		printk(KERN_ERR "Couldn't create dir /proc/%s/%s\n",				BASE_DIR, NAMED_DIR);		goto cleanup;	}	named_dir->owner = THIS_MODULE; 	/*	 * Create per-number subdirectory	 */	numbered_dir = proc_mkdir(NUMBERED_DIR, base_dir);	if (!numbered_dir) {		printk(KERN_ERR "Couldn't create dir /proc/%s/%s\n",				BASE_DIR, NUMBERED_DIR);		goto cleanup; 	}	numbered_dir->owner = THIS_MODULE; 	/*	 * Create all named nodes	 */	entry = srm_named_entries;	while (entry->name && entry->id) {		entry->proc_entry = create_proc_entry(entry->name,				0644, named_dir);		if (!entry->proc_entry)			goto cleanup; 		entry->proc_entry->data		= (void *) entry;		entry->proc_entry->owner	= THIS_MODULE;		entry->proc_entry->read_proc	= srm_env_read;		entry->proc_entry->write_proc	= srm_env_write; 		entry++;	} 	/*	 * Create all numbered nodes	 */	for (var_num = 0; var_num <= 255; var_num++) {		entry = &srm_numbered_entries[var_num];		entry->name = number[var_num]; 		entry->proc_entry = create_proc_entry(entry->name,				0644, numbered_dir);		if (!entry->proc_entry)			goto cleanup; 		entry->id			= var_num;		entry->proc_entry->data		= (void *) entry;		entry->proc_entry->owner	= THIS_MODULE;		entry->proc_entry->read_proc	= srm_env_read;		entry->proc_entry->write_proc	= srm_env_write;	} 	printk(KERN_INFO "%s: version %s loaded successfully\n", NAME,			VERSION); 	return 0; cleanup:	srm_env_cleanup(); 	return -ENOMEM;} static void __exitsrm_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);