| 1 | |
| 2 | |
| 3 | * /proc/bootconfig - Extra boot configuration
|
| 4 |
|
| 5 | #include <linux/fs.h>
|
| 6 | #include <linux/init.h>
|
| 7 | #include <linux/printk.h>
|
| 8 | #include <linux/proc_fs.h>
|
| 9 | #include <linux/seq_file.h>
|
| 10 | #include <linux/bootconfig.h>
|
| 11 | #include <linux/slab.h>
|
| 12 |
|
| 13 | static char *saved_boot_config;
|
| 14 |
|
| 15 | static int boot_config_proc_show(struct seq_file *m, void *v)
|
| 16 | {
|
| 17 | if (saved_boot_config)
|
| 18 | seq_puts(m, saved_boot_config);
|
| 19 | return 0;
|
| 20 | }
|
| 21 |
|
| 22 |
|
| 23 | #define rest(dst, end) ((end) > (dst) ? (end) - (dst) : 0)
|
| 24 |
|
| 25 |
|
| 26 | static int __init copy_xbc_key_value_list(char *dst, size_t size)
|
| 27 | {
|
| 28 | struct xbc_node *leaf, *vnode;
|
| 29 | char *key, *end = dst + size;
|
| 30 | const char *val;
|
| 31 | char q;
|
| 32 | int ret = 0;
|
| 33 |
|
| 34 | key = kzalloc(XBC_KEYLEN_MAX, GFP_KERNEL);
|
| 35 | if (!key)
|
| 36 | return -ENOMEM;
|
| 37 |
|
| 38 | xbc_for_each_key_value(leaf, val) {
|
| 39 | ret = xbc_node_compose_key(leaf, key, XBC_KEYLEN_MAX);
|
| 40 | if (ret < 0)
|
| 41 | break;
|
| 42 | ret = snprintf(dst, rest(dst, end), "%s = ", key);
|
| 43 | if (ret < 0)
|
| 44 | break;
|
| 45 | dst += ret;
|
| 46 | vnode = xbc_node_get_child(leaf);
|
| 47 | if (vnode) {
|
| 48 | xbc_array_for_each_value(vnode, val) {
|
| 49 | if (strchr(val, '"'))
|
| 50 | q = '\'';
|
| 51 | else
|
| 52 | q = '"';
|
| 53 | ret = snprintf(dst, rest(dst, end), "%c%s%c%s",
|
| 54 | q, val, q, xbc_node_is_array(vnode) ? ", " : "\n");
|
| 55 | if (ret < 0)
|
| 56 | goto out;
|
| 57 | dst += ret;
|
| 58 | }
|
| 59 | } else {
|
| 60 | ret = snprintf(dst, rest(dst, end), "\"\"\n");
|
| 61 | if (ret < 0)
|
| 62 | break;
|
| 63 | dst += ret;
|
| 64 | }
|
| 65 | }
|
| 66 | if (cmdline_has_extra_options() && ret >= 0 && boot_command_line[0]) {
|
| 67 | ret = snprintf(dst, rest(dst, end), "# Parameters from bootloader:\n# %s\n",
|
| 68 | boot_command_line);
|
| 69 | if (ret > 0)
|
| 70 | dst += ret;
|
| 71 | }
|
| 72 | out:
|
| 73 | kfree(key);
|
| 74 |
|
| 75 | return ret < 0 ? ret : dst - (end - size);
|
| 76 | }
|
| 77 |
|
| 78 | static int __init proc_boot_config_init(void)
|
| 79 | {
|
| 80 | int len;
|
| 81 |
|
| 82 | len = copy_xbc_key_value_list(NULL, 0);
|
| 83 | if (len < 0)
|
| 84 | return len;
|
| 85 |
|
| 86 | if (len > 0) {
|
| 87 | saved_boot_config = kzalloc(len + 1, GFP_KERNEL);
|
| 88 | if (!saved_boot_config)
|
| 89 | return -ENOMEM;
|
| 90 |
|
| 91 | len = copy_xbc_key_value_list(saved_boot_config, len + 1);
|
| 92 | if (len < 0) {
|
| 93 | kfree(saved_boot_config);
|
| 94 | return len;
|
| 95 | }
|
| 96 | }
|
| 97 |
|
| 98 | proc_create_single("bootconfig", 0, NULL, boot_config_proc_show);
|
| 99 |
|
| 100 | return 0;
|
| 101 | }
|
| 102 | fs_initcall(proc_boot_config_init);
|