1 /* 2 * Architecture specific debugfs files 3 * 4 * Copyright (C) 2007, Intel Corp. 5 * Huang Ying <ying.huang@intel.com> 6 * 7 * This file is released under the GPLv2. 8 */ 9 #include <linux/debugfs.h> 10 #include <linux/uaccess.h> 11 #include <linux/stat.h> 12 #include <linux/init.h> 13 #include <linux/io.h> 14 #include <linux/mm.h> 15 #include <linux/module.h> 16 17 #include <asm/setup.h> 18 19 struct dentry *arch_debugfs_dir; 20 EXPORT_SYMBOL(arch_debugfs_dir); 21 22 #ifdef CONFIG_DEBUG_BOOT_PARAMS 23 struct setup_data_node { 24 u64 paddr; 25 u32 type; 26 u32 len; 27 }; 28 29 static ssize_t 30 setup_data_read(struct file *file, char __user *user_buf, size_t count, 31 loff_t *ppos) 32 { 33 struct setup_data_node *node = file->private_data; 34 unsigned long remain; 35 loff_t pos = *ppos; 36 struct page *pg; 37 void *p; 38 u64 pa; 39 40 if (pos < 0) 41 return -EINVAL; 42 if (pos >= node->len) 43 return 0; 44 45 if (count > node->len - pos) 46 count = node->len - pos; 47 pa = node->paddr + sizeof(struct setup_data) + pos; 48 pg = pfn_to_page((pa + count - 1) >> PAGE_SHIFT); 49 if (PageHighMem(pg)) { 50 p = ioremap_cache(pa, count); 51 if (!p) 52 return -ENXIO; 53 } else { 54 p = __va(pa); 55 } 56 57 remain = copy_to_user(user_buf, p, count); 58 59 if (PageHighMem(pg)) 60 iounmap(p); 61 62 if (remain) 63 return -EFAULT; 64 65 *ppos = pos + count; 66 67 return count; 68 } 69 70 static int setup_data_open(struct inode *inode, struct file *file) 71 { 72 file->private_data = inode->i_private; 73 return 0; 74 } 75 76 static const struct file_operations fops_setup_data = { 77 .read = setup_data_read, 78 .open = setup_data_open, 79 }; 80 81 static int __init 82 create_setup_data_node(struct dentry *parent, int no, 83 struct setup_data_node *node) 84 { 85 struct dentry *d, *type, *data; 86 char buf[16]; 87 int error; 88 89 sprintf(buf, "%d", no); 90 d = debugfs_create_dir(buf, parent); 91 if (!d) { 92 error = -ENOMEM; 93 goto err_return; 94 } 95 type = debugfs_create_x32("type", S_IRUGO, d, &node->type); 96 if (!type) { 97 error = -ENOMEM; 98 goto err_dir; 99 } 100 data = debugfs_create_file("data", S_IRUGO, d, node, &fops_setup_data); 101 if (!data) { 102 error = -ENOMEM; 103 goto err_type; 104 } 105 return 0; 106 107 err_type: 108 debugfs_remove(type); 109 err_dir: 110 debugfs_remove(d); 111 err_return: 112 return error; 113 } 114 115 static int __init create_setup_data_nodes(struct dentry *parent) 116 { 117 struct setup_data_node *node; 118 struct setup_data *data; 119 int error, no = 0; 120 struct dentry *d; 121 struct page *pg; 122 u64 pa_data; 123 124 d = debugfs_create_dir("setup_data", parent); 125 if (!d) { 126 error = -ENOMEM; 127 goto err_return; 128 } 129 130 pa_data = boot_params.hdr.setup_data; 131 132 while (pa_data) { 133 node = kmalloc(sizeof(*node), GFP_KERNEL); 134 if (!node) { 135 error = -ENOMEM; 136 goto err_dir; 137 } 138 pg = pfn_to_page((pa_data+sizeof(*data)-1) >> PAGE_SHIFT); 139 if (PageHighMem(pg)) { 140 data = ioremap_cache(pa_data, sizeof(*data)); 141 if (!data) { 142 kfree(node); 143 error = -ENXIO; 144 goto err_dir; 145 } 146 } else { 147 data = __va(pa_data); 148 } 149 150 node->paddr = pa_data; 151 node->type = data->type; 152 node->len = data->len; 153 error = create_setup_data_node(d, no, node); 154 pa_data = data->next; 155 156 if (PageHighMem(pg)) 157 iounmap(data); 158 if (error) 159 goto err_dir; 160 no++; 161 } 162 return 0; 163 164 err_dir: 165 debugfs_remove(d); 166 err_return: 167 return error; 168 } 169 170 static struct debugfs_blob_wrapper boot_params_blob = { 171 .data = &boot_params, 172 .size = sizeof(boot_params), 173 }; 174 175 static int __init boot_params_kdebugfs_init(void) 176 { 177 struct dentry *dbp, *version, *data; 178 int error; 179 180 dbp = debugfs_create_dir("boot_params", NULL); 181 if (!dbp) { 182 error = -ENOMEM; 183 goto err_return; 184 } 185 version = debugfs_create_x16("version", S_IRUGO, dbp, 186 &boot_params.hdr.version); 187 if (!version) { 188 error = -ENOMEM; 189 goto err_dir; 190 } 191 data = debugfs_create_blob("data", S_IRUGO, dbp, 192 &boot_params_blob); 193 if (!data) { 194 error = -ENOMEM; 195 goto err_version; 196 } 197 error = create_setup_data_nodes(dbp); 198 if (error) 199 goto err_data; 200 return 0; 201 202 err_data: 203 debugfs_remove(data); 204 err_version: 205 debugfs_remove(version); 206 err_dir: 207 debugfs_remove(dbp); 208 err_return: 209 return error; 210 } 211 #endif 212 213 static int __init arch_kdebugfs_init(void) 214 { 215 int error = 0; 216 217 arch_debugfs_dir = debugfs_create_dir("x86", NULL); 218 if (!arch_debugfs_dir) 219 return -ENOMEM; 220 221 #ifdef CONFIG_DEBUG_BOOT_PARAMS 222 error = boot_params_kdebugfs_init(); 223 #endif 224 225 return error; 226 } 227 arch_initcall(arch_kdebugfs_init); 228