|  | /* | 
|  | * 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 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; | 
|  |  | 
|  | 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 int | 
|  | srm_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 void | 
|  | srm_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 __init | 
|  | srm_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 __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); |