drivers/pnp/pnpbios/proc.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 /*
   3  * /proc/bus/pnp interface for Plug and Play devices
   4  *
   5  * Written by David Hinds, dahinds@users.sourceforge.net
   6  * Modified by Thomas Hood
   7  *
   8  * The .../devices and .../<node> and .../boot/<node> files are
   9  * utilized by the lspnp and setpnp utilities, supplied with the
  10  * pcmcia-cs package.
  11  *     http://pcmcia-cs.sourceforge.net
  12  *
  13  * The .../escd file is utilized by the lsescd utility written by
  14  * Gunther Mayer.
  15  *
  16  * The .../legacy_device_resources file is not used yet.
  17  *
  18  * The other files are human-readable.
  19  */
  20
  21 #include <linux/module.h>
  22 #include <linux/kernel.h>
  23 #include <linux/slab.h>
  24 #include <linux/types.h>
  25 #include <linux/proc_fs.h>
  26 #include <linux/pnp.h>
  27 #include <linux/seq_file.h>
  28 #include <linux/init.h>
  29
  30 #include <linux/uaccess.h>
  31
  32 #include "pnpbios.h"
  33
  34 static struct proc_dir_entry *proc_pnp = NULL;
  35 static struct proc_dir_entry *proc_pnp_boot = NULL;
  36
  37 static int pnpconfig_proc_show(struct seq_file *m, void *v)
  38 {
  39         struct pnp_isa_config_struc pnps;
  40
  41         if (pnp_bios_isapnp_config(&pnps))
  42                 return -EIO;
  43         seq_printf(m, "structure_revision %d\n"
  44                       "number_of_CSNs %d\n"
  45                       "ISA_read_data_port 0x%x\n",
  46                    pnps.revision, pnps.no_csns, pnps.isa_rd_data_port);
  47         return 0;
  48 }
  49
  50 static int escd_info_proc_show(struct seq_file *m, void *v)
  51 {
  52         struct escd_info_struc escd;
  53
  54         if (pnp_bios_escd_info(&escd))
  55                 return -EIO;
  56         seq_printf(m, "min_ESCD_write_size %d\n"
  57                         "ESCD_size %d\n"
  58                         "NVRAM_base 0x%x\n",
  59                         escd.min_escd_write_size,
  60                         escd.escd_size, escd.nv_storage_base);
  61         return 0;
  62 }
  63
  64 #define MAX_SANE_ESCD_SIZE (32*1024)
  65 static int escd_proc_show(struct seq_file *m, void *v)
  66 {
  67         struct escd_info_struc escd;
  68         char *tmpbuf;
  69         int escd_size;
  70
  71         if (pnp_bios_escd_info(&escd))
  72                 return -EIO;
  73
  74         /* sanity check */
  75         if (escd.escd_size > MAX_SANE_ESCD_SIZE) {
  76                 printk(KERN_ERR
  77                        "PnPBIOS: %s: ESCD size reported by BIOS escd_info call is too great\n", __func__);
  78                 return -EFBIG;
  79         }
  80
  81         tmpbuf = kzalloc(escd.escd_size, GFP_KERNEL);
  82         if (!tmpbuf)
  83                 return -ENOMEM;
  84
  85         if (pnp_bios_read_escd(tmpbuf, escd.nv_storage_base)) {
  86                 kfree(tmpbuf);
  87                 return -EIO;
  88         }
  89
  90         escd_size =
  91             (unsigned char)(tmpbuf[0]) + (unsigned char)(tmpbuf[1]) * 256;
  92
  93         /* sanity check */
  94         if (escd_size > MAX_SANE_ESCD_SIZE) {
  95                 printk(KERN_ERR "PnPBIOS: %s: ESCD size reported by"
  96                                 " BIOS read_escd call is too great\n", __func__);
  97                 kfree(tmpbuf);
  98                 return -EFBIG;
  99         }
 100
 101         seq_write(m, tmpbuf, escd_size);
 102         kfree(tmpbuf);
 103         return 0;
 104 }
 105
 106 static int pnp_legacyres_proc_show(struct seq_file *m, void *v)
 107 {
 108         void *buf;
 109
 110         buf = kmalloc(65536, GFP_KERNEL);
 111         if (!buf)
 112                 return -ENOMEM;
 113         if (pnp_bios_get_stat_res(buf)) {
 114                 kfree(buf);
 115                 return -EIO;
 116         }
 117
 118         seq_write(m, buf, 65536);
 119         kfree(buf);
 120         return 0;
 121 }
 122
 123 static int pnp_devices_proc_show(struct seq_file *m, void *v)
 124 {
 125         struct pnp_bios_node *node;
 126         u8 nodenum;
 127
 128         node = kzalloc(node_info.max_node_size, GFP_KERNEL);
 129         if (!node)
 130                 return -ENOMEM;
 131
 132         for (nodenum = 0; nodenum < 0xff;) {
 133                 u8 thisnodenum = nodenum;
 134
 135                 if (pnp_bios_get_dev_node(&nodenum, PNPMODE_DYNAMIC, node))
 136                         break;
 137                 seq_printf(m, "%02x\t%08x\t%3phC\t%04x\n",
 138                              node->handle, node->eisa_id,
 139                              node->type_code, node->flags);
 140                 if (nodenum <= thisnodenum) {
 141                         printk(KERN_ERR
 142                                "%s Node number 0x%x is out of sequence following node 0x%x. Aborting.\n",
 143                                "PnPBIOS: proc_read_devices:",
 144                                (unsigned int)nodenum,
 145                                (unsigned int)thisnodenum);
 146                         break;
 147                 }
 148         }
 149         kfree(node);
 150         return 0;
 151 }
 152
 153 static int pnpbios_proc_show(struct seq_file *m, void *v)
 154 {
 155         void *data = m->private;
 156         struct pnp_bios_node *node;
 157         int boot = (long)data >> 8;
 158         u8 nodenum = (long)data;
 159         int len;
 160
 161         node = kzalloc(node_info.max_node_size, GFP_KERNEL);
 162         if (!node)
 163                 return -ENOMEM;
 164         if (pnp_bios_get_dev_node(&nodenum, boot, node)) {
 165                 kfree(node);
 166                 return -EIO;
 167         }
 168         len = node->size - sizeof(struct pnp_bios_node);
 169         seq_write(m, node->data, len);
 170         kfree(node);
 171         return 0;
 172 }
 173
 174 static int pnpbios_proc_open(struct inode *inode, struct file *file)
 175 {
 176         return single_open(file, pnpbios_proc_show, PDE_DATA(inode));
 177 }
 178
 179 static ssize_t pnpbios_proc_write(struct file *file, const char __user *buf,
 180                                   size_t count, loff_t *pos)
 181 {
 182         void *data = PDE_DATA(file_inode(file));
 183         struct pnp_bios_node *node;
 184         int boot = (long)data >> 8;
 185         u8 nodenum = (long)data;
 186         int ret = count;
 187
 188         node = kzalloc(node_info.max_node_size, GFP_KERNEL);
 189         if (!node)
 190                 return -ENOMEM;
 191         if (pnp_bios_get_dev_node(&nodenum, boot, node)) {
 192                 ret = -EIO;
 193                 goto out;
 194         }
 195         if (count != node->size - sizeof(struct pnp_bios_node)) {
 196                 ret = -EINVAL;
 197                 goto out;
 198         }
 199         if (copy_from_user(node->data, buf, count)) {
 200                 ret = -EFAULT;
 201                 goto out;
 202         }
 203         if (pnp_bios_set_dev_node(node->handle, boot, node) != 0) {
 204                 ret = -EINVAL;
 205                 goto out;
 206         }
 207         ret = count;
 208 out:
 209         kfree(node);
 210         return ret;
 211 }
 212
 213 static const struct proc_ops pnpbios_proc_ops = {
 214         .proc_open      = pnpbios_proc_open,
 215         .proc_read      = seq_read,
 216         .proc_lseek     = seq_lseek,
 217         .proc_release   = single_release,
 218         .proc_write     = pnpbios_proc_write,
 219 };
 220
 221 int pnpbios_interface_attach_device(struct pnp_bios_node *node)
 222 {
 223         char name[3];
 224
 225         sprintf(name, "%02x", node->handle);
 226
 227         if (!proc_pnp)
 228                 return -EIO;
 229         if (!pnpbios_dont_use_current_config) {
 230                 proc_create_data(name, 0644, proc_pnp, &pnpbios_proc_ops,
 231                                  (void *)(long)(node->handle));
 232         }
 233
 234         if (!proc_pnp_boot)
 235                 return -EIO;
 236         if (proc_create_data(name, 0644, proc_pnp_boot, &pnpbios_proc_ops,
 237                              (void *)(long)(node->handle + 0x100)))
 238                 return 0;
 239         return -EIO;
 240 }
 241
 242 /*
 243  * When this is called, pnpbios functions are assumed to
 244  * work and the pnpbios_dont_use_current_config flag
 245  * should already have been set to the appropriate value
 246  */
 247 int __init pnpbios_proc_init(void)
 248 {
 249         proc_pnp = proc_mkdir("bus/pnp", NULL);
 250         if (!proc_pnp)
 251                 return -EIO;
 252         proc_pnp_boot = proc_mkdir("boot", proc_pnp);
 253         if (!proc_pnp_boot)
 254                 return -EIO;
 255         proc_create_single("devices", 0, proc_pnp, pnp_devices_proc_show);
 256         proc_create_single("configuration_info", 0, proc_pnp,
 257                         pnpconfig_proc_show);
 258         proc_create_single("escd_info", 0, proc_pnp, escd_info_proc_show);
 259         proc_create_single("escd", S_IRUSR, proc_pnp, escd_proc_show);
 260         proc_create_single("legacy_device_resources", 0, proc_pnp,
 261                         pnp_legacyres_proc_show);
 262         return 0;
 263 }
 264
 265 void __exit pnpbios_proc_exit(void)
 266 {
 267         int i;
 268         char name[3];
 269
 270         if (!proc_pnp)
 271                 return;
 272
 273         for (i = 0; i < 0xff; i++) {
 274                 sprintf(name, "%02x", i);
 275                 if (!pnpbios_dont_use_current_config)
 276                         remove_proc_entry(name, proc_pnp);
 277                 remove_proc_entry(name, proc_pnp_boot);
 278         }
 279         remove_proc_entry("legacy_device_resources", proc_pnp);
 280         remove_proc_entry("escd", proc_pnp);
 281         remove_proc_entry("escd_info", proc_pnp);
 282         remove_proc_entry("configuration_info", proc_pnp);
 283         remove_proc_entry("devices", proc_pnp);
 284         remove_proc_entry("boot", proc_pnp);
 285         remove_proc_entry("bus/pnp", NULL);
 286 }