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/export.h> 12 #include <linux/slab.h> 13 #include <linux/init.h> 14 #include <linux/stat.h> 15 #include <linux/io.h> 16 #include <linux/mm.h> 17 18 #include <asm/setup.h> 19 20 struct dentry *arch_debugfs_dir; 21 EXPORT_SYMBOL(arch_debugfs_dir); 22 23 #ifdef CONFIG_DEBUG_BOOT_PARAMS 24 struct setup_data_node { 25 u64 paddr; 26 u32 type; 27 u32 len; 28 }; 29 30 static ssize_t setup_data_read(struct file *file, char __user *user_buf, 31 size_t count, loff_t *ppos) 32 { 33 struct setup_data_node *node = file->private_data; 34 unsigned long remain; 35 loff_t pos = *ppos; 36 void *p; 37 u64 pa; 38 39 if (pos < 0) 40 return -EINVAL; 41 42 if (pos >= node->len) 43 return 0; 44 45 if (count > node->len - pos) 46 count = node->len - pos; 47 48 pa = node->paddr + sizeof(struct setup_data) + pos; 49 p = memremap(pa, count, MEMREMAP_WB); 50 if (!p) 51 return -ENOMEM; 52 53 remain = copy_to_user(user_buf, p, count); 54 55 memunmap(p); 56 57 if (remain) 58 return -EFAULT; 59 60 *ppos = pos + count; 61 62 return count; 63 } 64 65 static const struct file_operations fops_setup_data = { 66 .read = setup_data_read, 67 .open = simple_open, 68 .llseek = default_llseek, 69 }; 70 71 static int __init 72 create_setup_data_node(struct dentry *parent, int no, 73 struct setup_data_node *node) 74 { 75 struct dentry *d, *type, *data; 76 char buf[16]; 77 78 sprintf(buf, "%d", no); 79 d = debugfs_create_dir(buf, parent); 80 if (!d) 81 return -ENOMEM; 82 83 type = debugfs_create_x32("type", S_IRUGO, d, &node->type); 84 if (!type) 85 goto err_dir; 86 87 data = debugfs_create_file("data", S_IRUGO, d, node, &fops_setup_data); 88 if (!data) 89 goto err_type; 90 91 return 0; 92 93 err_type: 94 debugfs_remove(type); 95 err_dir: 96 debugfs_remove(d); 97 return -ENOMEM; 98 } 99 100 static int __init create_setup_data_nodes(struct dentry *parent) 101 { 102 struct setup_data_node *node; 103 struct setup_data *data; 104 int error; 105 struct dentry *d; 106 u64 pa_data; 107 int no = 0; 108 109 d = debugfs_create_dir("setup_data", parent); 110 if (!d) 111 return -ENOMEM; 112 113 pa_data = boot_params.hdr.setup_data; 114 115 while (pa_data) { 116 node = kmalloc(sizeof(*node), GFP_KERNEL); 117 if (!node) { 118 error = -ENOMEM; 119 goto err_dir; 120 } 121 122 data = memremap(pa_data, sizeof(*data), MEMREMAP_WB); 123 if (!data) { 124 kfree(node); 125 error = -ENOMEM; 126 goto err_dir; 127 } 128 129 node->paddr = pa_data; 130 node->type = data->type; 131 node->len = data->len; 132 error = create_setup_data_node(d, no, node); 133 pa_data = data->next; 134 135 memunmap(data); 136 if (error) 137 goto err_dir; 138 no++; 139 } 140 141 return 0; 142 143 err_dir: 144 debugfs_remove(d); 145 return error; 146 } 147 148 static struct debugfs_blob_wrapper boot_params_blob = { 149 .data = &boot_params, 150 .size = sizeof(boot_params), 151 }; 152 153 static int __init boot_params_kdebugfs_init(void) 154 { 155 struct dentry *dbp, *version, *data; 156 int error = -ENOMEM; 157 158 dbp = debugfs_create_dir("boot_params", arch_debugfs_dir); 159 if (!dbp) 160 return -ENOMEM; 161 162 version = debugfs_create_x16("version", S_IRUGO, dbp, 163 &boot_params.hdr.version); 164 if (!version) 165 goto err_dir; 166 167 data = debugfs_create_blob("data", S_IRUGO, dbp, 168 &boot_params_blob); 169 if (!data) 170 goto err_version; 171 172 error = create_setup_data_nodes(dbp); 173 if (error) 174 goto err_data; 175 176 return 0; 177 178 err_data: 179 debugfs_remove(data); 180 err_version: 181 debugfs_remove(version); 182 err_dir: 183 debugfs_remove(dbp); 184 return error; 185 } 186 #endif /* CONFIG_DEBUG_BOOT_PARAMS */ 187 188 static int __init arch_kdebugfs_init(void) 189 { 190 int error = 0; 191 192 arch_debugfs_dir = debugfs_create_dir("x86", NULL); 193 if (!arch_debugfs_dir) 194 return -ENOMEM; 195 196 #ifdef CONFIG_DEBUG_BOOT_PARAMS 197 error = boot_params_kdebugfs_init(); 198 #endif 199 200 return error; 201 } 202 arch_initcall(arch_kdebugfs_init); 203