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/module.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 struct page *pg; 37 void *p; 38 u64 pa; 39 40 if (pos < 0) 41 return -EINVAL; 42 43 if (pos >= node->len) 44 return 0; 45 46 if (count > node->len - pos) 47 count = node->len - pos; 48 49 pa = node->paddr + sizeof(struct setup_data) + pos; 50 pg = pfn_to_page((pa + count - 1) >> PAGE_SHIFT); 51 if (PageHighMem(pg)) { 52 p = ioremap_cache(pa, count); 53 if (!p) 54 return -ENXIO; 55 } else 56 p = __va(pa); 57 58 remain = copy_to_user(user_buf, p, count); 59 60 if (PageHighMem(pg)) 61 iounmap(p); 62 63 if (remain) 64 return -EFAULT; 65 66 *ppos = pos + count; 67 68 return count; 69 } 70 71 static int setup_data_open(struct inode *inode, struct file *file) 72 { 73 file->private_data = inode->i_private; 74 75 return 0; 76 } 77 78 static const struct file_operations fops_setup_data = { 79 .read = setup_data_read, 80 .open = setup_data_open, 81 .llseek = default_llseek, 82 }; 83 84 static int __init 85 create_setup_data_node(struct dentry *parent, int no, 86 struct setup_data_node *node) 87 { 88 struct dentry *d, *type, *data; 89 char buf[16]; 90 91 sprintf(buf, "%d", no); 92 d = debugfs_create_dir(buf, parent); 93 if (!d) 94 return -ENOMEM; 95 96 type = debugfs_create_x32("type", S_IRUGO, d, &node->type); 97 if (!type) 98 goto err_dir; 99 100 data = debugfs_create_file("data", S_IRUGO, d, node, &fops_setup_data); 101 if (!data) 102 goto err_type; 103 104 return 0; 105 106 err_type: 107 debugfs_remove(type); 108 err_dir: 109 debugfs_remove(d); 110 return -ENOMEM; 111 } 112 113 static int __init create_setup_data_nodes(struct dentry *parent) 114 { 115 struct setup_data_node *node; 116 struct setup_data *data; 117 int error = -ENOMEM; 118 struct dentry *d; 119 struct page *pg; 120 u64 pa_data; 121 int no = 0; 122 123 d = debugfs_create_dir("setup_data", parent); 124 if (!d) 125 return -ENOMEM; 126 127 pa_data = boot_params.hdr.setup_data; 128 129 while (pa_data) { 130 node = kmalloc(sizeof(*node), GFP_KERNEL); 131 if (!node) 132 goto err_dir; 133 134 pg = pfn_to_page((pa_data+sizeof(*data)-1) >> PAGE_SHIFT); 135 if (PageHighMem(pg)) { 136 data = ioremap_cache(pa_data, sizeof(*data)); 137 if (!data) { 138 kfree(node); 139 error = -ENXIO; 140 goto err_dir; 141 } 142 } else 143 data = __va(pa_data); 144 145 node->paddr = pa_data; 146 node->type = data->type; 147 node->len = data->len; 148 error = create_setup_data_node(d, no, node); 149 pa_data = data->next; 150 151 if (PageHighMem(pg)) 152 iounmap(data); 153 if (error) 154 goto err_dir; 155 no++; 156 } 157 158 return 0; 159 160 err_dir: 161 debugfs_remove(d); 162 return error; 163 } 164 165 static struct debugfs_blob_wrapper boot_params_blob = { 166 .data = &boot_params, 167 .size = sizeof(boot_params), 168 }; 169 170 static int __init boot_params_kdebugfs_init(void) 171 { 172 struct dentry *dbp, *version, *data; 173 int error = -ENOMEM; 174 175 dbp = debugfs_create_dir("boot_params", NULL); 176 if (!dbp) 177 return -ENOMEM; 178 179 version = debugfs_create_x16("version", S_IRUGO, dbp, 180 &boot_params.hdr.version); 181 if (!version) 182 goto err_dir; 183 184 data = debugfs_create_blob("data", S_IRUGO, dbp, 185 &boot_params_blob); 186 if (!data) 187 goto err_version; 188 189 error = create_setup_data_nodes(dbp); 190 if (error) 191 goto err_data; 192 193 return 0; 194 195 err_data: 196 debugfs_remove(data); 197 err_version: 198 debugfs_remove(version); 199 err_dir: 200 debugfs_remove(dbp); 201 return error; 202 } 203 #endif /* CONFIG_DEBUG_BOOT_PARAMS */ 204 205 static int __init arch_kdebugfs_init(void) 206 { 207 int error = 0; 208 209 arch_debugfs_dir = debugfs_create_dir("x86", NULL); 210 if (!arch_debugfs_dir) 211 return -ENOMEM; 212 213 #ifdef CONFIG_DEBUG_BOOT_PARAMS 214 error = boot_params_kdebugfs_init(); 215 #endif 216 217 return error; 218 } 219 arch_initcall(arch_kdebugfs_init); 220