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 }; 82 83 static int __init 84 create_setup_data_node(struct dentry *parent, int no, 85 struct setup_data_node *node) 86 { 87 struct dentry *d, *type, *data; 88 char buf[16]; 89 90 sprintf(buf, "%d", no); 91 d = debugfs_create_dir(buf, parent); 92 if (!d) 93 return -ENOMEM; 94 95 type = debugfs_create_x32("type", S_IRUGO, d, &node->type); 96 if (!type) 97 goto err_dir; 98 99 data = debugfs_create_file("data", S_IRUGO, d, node, &fops_setup_data); 100 if (!data) 101 goto err_type; 102 103 return 0; 104 105 err_type: 106 debugfs_remove(type); 107 err_dir: 108 debugfs_remove(d); 109 return -ENOMEM; 110 } 111 112 static int __init create_setup_data_nodes(struct dentry *parent) 113 { 114 struct setup_data_node *node; 115 struct setup_data *data; 116 int error = -ENOMEM; 117 struct dentry *d; 118 struct page *pg; 119 u64 pa_data; 120 int no = 0; 121 122 d = debugfs_create_dir("setup_data", parent); 123 if (!d) 124 return -ENOMEM; 125 126 pa_data = boot_params.hdr.setup_data; 127 128 while (pa_data) { 129 node = kmalloc(sizeof(*node), GFP_KERNEL); 130 if (!node) 131 goto err_dir; 132 133 pg = pfn_to_page((pa_data+sizeof(*data)-1) >> PAGE_SHIFT); 134 if (PageHighMem(pg)) { 135 data = ioremap_cache(pa_data, sizeof(*data)); 136 if (!data) { 137 kfree(node); 138 error = -ENXIO; 139 goto err_dir; 140 } 141 } else 142 data = __va(pa_data); 143 144 node->paddr = pa_data; 145 node->type = data->type; 146 node->len = data->len; 147 error = create_setup_data_node(d, no, node); 148 pa_data = data->next; 149 150 if (PageHighMem(pg)) 151 iounmap(data); 152 if (error) 153 goto err_dir; 154 no++; 155 } 156 157 return 0; 158 159 err_dir: 160 debugfs_remove(d); 161 return error; 162 } 163 164 static struct debugfs_blob_wrapper boot_params_blob = { 165 .data = &boot_params, 166 .size = sizeof(boot_params), 167 }; 168 169 static int __init boot_params_kdebugfs_init(void) 170 { 171 struct dentry *dbp, *version, *data; 172 int error = -ENOMEM; 173 174 dbp = debugfs_create_dir("boot_params", NULL); 175 if (!dbp) 176 return -ENOMEM; 177 178 version = debugfs_create_x16("version", S_IRUGO, dbp, 179 &boot_params.hdr.version); 180 if (!version) 181 goto err_dir; 182 183 data = debugfs_create_blob("data", S_IRUGO, dbp, 184 &boot_params_blob); 185 if (!data) 186 goto err_version; 187 188 error = create_setup_data_nodes(dbp); 189 if (error) 190 goto err_data; 191 192 return 0; 193 194 err_data: 195 debugfs_remove(data); 196 err_version: 197 debugfs_remove(version); 198 err_dir: 199 debugfs_remove(dbp); 200 return error; 201 } 202 #endif /* CONFIG_DEBUG_BOOT_PARAMS */ 203 204 static int __init arch_kdebugfs_init(void) 205 { 206 int error = 0; 207 208 arch_debugfs_dir = debugfs_create_dir("x86", NULL); 209 if (!arch_debugfs_dir) 210 return -ENOMEM; 211 212 #ifdef CONFIG_DEBUG_BOOT_PARAMS 213 error = boot_params_kdebugfs_init(); 214 #endif 215 216 return error; 217 } 218 arch_initcall(arch_kdebugfs_init); 219