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-rw-r--r--arch/alpha/kernel/srm_env.c218
1 files changed, 218 insertions, 0 deletions
diff --git a/arch/alpha/kernel/srm_env.c b/arch/alpha/kernel/srm_env.c
new file mode 100644
index 0000000000..217b4dca51
--- /dev/null
+++ b/arch/alpha/kernel/srm_env.c
@@ -0,0 +1,218 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * 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 a modified version of Erik Mouw's example proc
+ * interface, 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!
+ */
+
+#include <linux/kernel.h>
+#include <linux/gfp.h>
+#include <linux/module.h>
+#include <linux/init.h>
+#include <linux/proc_fs.h>
+#include <linux/seq_file.h>
+#include <asm/console.h>
+#include <linux/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;
+} 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 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 int srm_env_proc_show(struct seq_file *m, void *v)
+{
+ unsigned long ret;
+ unsigned long id = (unsigned long)m->private;
+ char *page;
+
+ page = (char *)__get_free_page(GFP_USER);
+ if (!page)
+ return -ENOMEM;
+
+ ret = callback_getenv(id, page, PAGE_SIZE);
+
+ if ((ret >> 61) == 0) {
+ seq_write(m, page, ret);
+ ret = 0;
+ } else
+ ret = -EFAULT;
+ free_page((unsigned long)page);
+ return ret;
+}
+
+static int srm_env_proc_open(struct inode *inode, struct file *file)
+{
+ return single_open(file, srm_env_proc_show, pde_data(inode));
+}
+
+static ssize_t srm_env_proc_write(struct file *file, const char __user *buffer,
+ size_t count, loff_t *pos)
+{
+ int res;
+ unsigned long id = (unsigned long)pde_data(file_inode(file));
+ char *buf = (char *) __get_free_page(GFP_USER);
+ unsigned long ret1, ret2;
+
+ 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(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 const struct proc_ops srm_env_proc_ops = {
+ .proc_open = srm_env_proc_open,
+ .proc_read = seq_read,
+ .proc_lseek = seq_lseek,
+ .proc_release = single_release,
+ .proc_write = srm_env_proc_write,
+};
+
+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", __func__);
+ return -ENODEV;
+ }
+
+ /*
+ * 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);
+ return -ENOMEM;
+ }
+
+ /*
+ * 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;
+ }
+
+ /*
+ * 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;
+
+ }
+
+ /*
+ * Create all named nodes
+ */
+ entry = srm_named_entries;
+ while (entry->name && entry->id) {
+ if (!proc_create_data(entry->name, 0644, named_dir,
+ &srm_env_proc_ops, (void *)entry->id))
+ goto cleanup;
+ entry++;
+ }
+
+ /*
+ * Create all numbered nodes
+ */
+ for (var_num = 0; var_num <= 255; var_num++) {
+ char name[4];
+ sprintf(name, "%ld", var_num);
+ if (!proc_create_data(name, 0644, numbered_dir,
+ &srm_env_proc_ops, (void *)var_num))
+ goto cleanup;
+ }
+
+ printk(KERN_INFO "%s: version %s loaded successfully\n", NAME,
+ VERSION);
+
+ return 0;
+
+cleanup:
+ remove_proc_subtree(BASE_DIR, NULL);
+ return -ENOMEM;
+}
+
+static void __exit
+srm_env_exit(void)
+{
+ remove_proc_subtree(BASE_DIR, NULL);
+ printk(KERN_INFO "%s: unloaded successfully\n", NAME);
+}
+
+module_init(srm_env_init);
+module_exit(srm_env_exit);