arch/powerpc/platforms/pseries/reconfig.c

   1 /*
   2  * pSeries_reconfig.c - support for dynamic reconfiguration (including PCI
   3  * Hotplug and Dynamic Logical Partitioning on RPA platforms).
   4  *
   5  * Copyright (C) 2005 Nathan Lynch
   6  * Copyright (C) 2005 IBM Corporation
   7  *
   8  *
   9  *      This program is free software; you can redistribute it and/or
  10  *      modify it under the terms of the GNU General Public License version
  11  *      2 as published by the Free Software Foundation.
  12  */
  13
  14 #include <linux/kernel.h>
  15 #include <linux/notifier.h>
  16 #include <linux/proc_fs.h>
  17 #include <linux/slab.h>
  18 #include <linux/of.h>
  19
  20 #include <asm/prom.h>
  21 #include <asm/machdep.h>
  22 #include <linux/uaccess.h>
  23 #include <asm/mmu.h>
  24
  25 #include "of_helpers.h"
  26
  27 static int pSeries_reconfig_add_node(const char *path, struct property *proplist)
  28 {
  29         struct device_node *np;
  30         int err = -ENOMEM;
  31
  32         np = kzalloc(sizeof(*np), GFP_KERNEL);
  33         if (!np)
  34                 goto out_err;
  35
  36         np->full_name = kstrdup(path, GFP_KERNEL);
  37         if (!np->full_name)
  38                 goto out_err;
  39
  40         np->properties = proplist;
  41         of_node_set_flag(np, OF_DYNAMIC);
  42         of_node_init(np);
  43
  44         np->parent = pseries_of_derive_parent(path);
  45         if (IS_ERR(np->parent)) {
  46                 err = PTR_ERR(np->parent);
  47                 goto out_err;
  48         }
  49
  50         err = of_attach_node(np);
  51         if (err) {
  52                 printk(KERN_ERR "Failed to add device node %s\n", path);
  53                 goto out_err;
  54         }
  55
  56         of_node_put(np->parent);
  57
  58         return 0;
  59
  60 out_err:
  61         if (np) {
  62                 of_node_put(np->parent);
  63                 kfree(np->full_name);
  64                 kfree(np);
  65         }
  66         return err;
  67 }
  68
  69 static int pSeries_reconfig_remove_node(struct device_node *np)
  70 {
  71         struct device_node *parent, *child;
  72
  73         parent = of_get_parent(np);
  74         if (!parent)
  75                 return -EINVAL;
  76
  77         if ((child = of_get_next_child(np, NULL))) {
  78                 of_node_put(child);
  79                 of_node_put(parent);
  80                 return -EBUSY;
  81         }
  82
  83         of_detach_node(np);
  84         of_node_put(parent);
  85         return 0;
  86 }
  87
  88 /*
  89  * /proc/powerpc/ofdt - yucky binary interface for adding and removing
  90  * OF device nodes.  Should be deprecated as soon as we get an
  91  * in-kernel wrapper for the RTAS ibm,configure-connector call.
  92  */
  93
  94 static void release_prop_list(const struct property *prop)
  95 {
  96         struct property *next;
  97         for (; prop; prop = next) {
  98                 next = prop->next;
  99                 kfree(prop->name);
 100                 kfree(prop->value);
 101                 kfree(prop);
 102         }
 103
 104 }
 105
 106 /**
 107  * parse_next_property - process the next property from raw input buffer
 108  * @buf: input buffer, must be nul-terminated
 109  * @end: end of the input buffer + 1, for validation
 110  * @name: return value; set to property name in buf
 111  * @length: return value; set to length of value
 112  * @value: return value; set to the property value in buf
 113  *
 114  * Note that the caller must make copies of the name and value returned,
 115  * this function does no allocation or copying of the data.  Return value
 116  * is set to the next name in buf, or NULL on error.
 117  */
 118 static char * parse_next_property(char *buf, char *end, char **name, int *length,
 119                                   unsigned char **value)
 120 {
 121         char *tmp;
 122
 123         *name = buf;
 124
 125         tmp = strchr(buf, ' ');
 126         if (!tmp) {
 127                 printk(KERN_ERR "property parse failed in %s at line %d\n",
 128                        __func__, __LINE__);
 129                 return NULL;
 130         }
 131         *tmp = '\0';
 132
 133         if (++tmp >= end) {
 134                 printk(KERN_ERR "property parse failed in %s at line %d\n",
 135                        __func__, __LINE__);
 136                 return NULL;
 137         }
 138
 139         /* now we're on the length */
 140         *length = -1;
 141         *length = simple_strtoul(tmp, &tmp, 10);
 142         if (*length == -1) {
 143                 printk(KERN_ERR "property parse failed in %s at line %d\n",
 144                        __func__, __LINE__);
 145                 return NULL;
 146         }
 147         if (*tmp != ' ' || ++tmp >= end) {
 148                 printk(KERN_ERR "property parse failed in %s at line %d\n",
 149                        __func__, __LINE__);
 150                 return NULL;
 151         }
 152
 153         /* now we're on the value */
 154         *value = tmp;
 155         tmp += *length;
 156         if (tmp > end) {
 157                 printk(KERN_ERR "property parse failed in %s at line %d\n",
 158                        __func__, __LINE__);
 159                 return NULL;
 160         }
 161         else if (tmp < end && *tmp != ' ' && *tmp != '\0') {
 162                 printk(KERN_ERR "property parse failed in %s at line %d\n",
 163                        __func__, __LINE__);
 164                 return NULL;
 165         }
 166         tmp++;
 167
 168         /* and now we should be on the next name, or the end */
 169         return tmp;
 170 }
 171
 172 static struct property *new_property(const char *name, const int length,
 173                                      const unsigned char *value, struct property *last)
 174 {
 175         struct property *new = kzalloc(sizeof(*new), GFP_KERNEL);
 176
 177         if (!new)
 178                 return NULL;
 179
 180         if (!(new->name = kstrdup(name, GFP_KERNEL)))
 181                 goto cleanup;
 182         if (!(new->value = kmalloc(length + 1, GFP_KERNEL)))
 183                 goto cleanup;
 184
 185         memcpy(new->value, value, length);
 186         *(((char *)new->value) + length) = 0;
 187         new->length = length;
 188         new->next = last;
 189         return new;
 190
 191 cleanup:
 192         kfree(new->name);
 193         kfree(new->value);
 194         kfree(new);
 195         return NULL;
 196 }
 197
 198 static int do_add_node(char *buf, size_t bufsize)
 199 {
 200         char *path, *end, *name;
 201         struct device_node *np;
 202         struct property *prop = NULL;
 203         unsigned char* value;
 204         int length, rv = 0;
 205
 206         end = buf + bufsize;
 207         path = buf;
 208         buf = strchr(buf, ' ');
 209         if (!buf)
 210                 return -EINVAL;
 211         *buf = '\0';
 212         buf++;
 213
 214         if ((np = of_find_node_by_path(path))) {
 215                 of_node_put(np);
 216                 return -EINVAL;
 217         }
 218
 219         /* rv = build_prop_list(tmp, bufsize - (tmp - buf), &proplist); */
 220         while (buf < end &&
 221                (buf = parse_next_property(buf, end, &name, &length, &value))) {
 222                 struct property *last = prop;
 223
 224                 prop = new_property(name, length, value, last);
 225                 if (!prop) {
 226                         rv = -ENOMEM;
 227                         prop = last;
 228                         goto out;
 229                 }
 230         }
 231         if (!buf) {
 232                 rv = -EINVAL;
 233                 goto out;
 234         }
 235
 236         rv = pSeries_reconfig_add_node(path, prop);
 237
 238 out:
 239         if (rv)
 240                 release_prop_list(prop);
 241         return rv;
 242 }
 243
 244 static int do_remove_node(char *buf)
 245 {
 246         struct device_node *node;
 247         int rv = -ENODEV;
 248
 249         if ((node = of_find_node_by_path(buf)))
 250                 rv = pSeries_reconfig_remove_node(node);
 251
 252         of_node_put(node);
 253         return rv;
 254 }
 255
 256 static char *parse_node(char *buf, size_t bufsize, struct device_node **npp)
 257 {
 258         char *handle_str;
 259         phandle handle;
 260         *npp = NULL;
 261
 262         handle_str = buf;
 263
 264         buf = strchr(buf, ' ');
 265         if (!buf)
 266                 return NULL;
 267         *buf = '\0';
 268         buf++;
 269
 270         handle = simple_strtoul(handle_str, NULL, 0);
 271
 272         *npp = of_find_node_by_phandle(handle);
 273         return buf;
 274 }
 275
 276 static int do_add_property(char *buf, size_t bufsize)
 277 {
 278         struct property *prop = NULL;
 279         struct device_node *np;
 280         unsigned char *value;
 281         char *name, *end;
 282         int length;
 283         end = buf + bufsize;
 284         buf = parse_node(buf, bufsize, &np);
 285
 286         if (!np)
 287                 return -ENODEV;
 288
 289         if (parse_next_property(buf, end, &name, &length, &value) == NULL)
 290                 return -EINVAL;
 291
 292         prop = new_property(name, length, value, NULL);
 293         if (!prop)
 294                 return -ENOMEM;
 295
 296         of_add_property(np, prop);
 297
 298         return 0;
 299 }
 300
 301 static int do_remove_property(char *buf, size_t bufsize)
 302 {
 303         struct device_node *np;
 304         char *tmp;
 305         buf = parse_node(buf, bufsize, &np);
 306
 307         if (!np)
 308                 return -ENODEV;
 309
 310         tmp = strchr(buf,' ');
 311         if (tmp)
 312                 *tmp = '\0';
 313
 314         if (strlen(buf) == 0)
 315                 return -EINVAL;
 316
 317         return of_remove_property(np, of_find_property(np, buf, NULL));
 318 }
 319
 320 static int do_update_property(char *buf, size_t bufsize)
 321 {
 322         struct device_node *np;
 323         unsigned char *value;
 324         char *name, *end, *next_prop;
 325         int length;
 326         struct property *newprop;
 327         buf = parse_node(buf, bufsize, &np);
 328         end = buf + bufsize;
 329
 330         if (!np)
 331                 return -ENODEV;
 332
 333         next_prop = parse_next_property(buf, end, &name, &length, &value);
 334         if (!next_prop)
 335                 return -EINVAL;
 336
 337         if (!strlen(name))
 338                 return -ENODEV;
 339
 340         newprop = new_property(name, length, value, NULL);
 341         if (!newprop)
 342                 return -ENOMEM;
 343
 344         if (!strcmp(name, "slb-size") || !strcmp(name, "ibm,slb-size"))
 345                 slb_set_size(*(int *)value);
 346
 347         return of_update_property(np, newprop);
 348 }
 349
 350 /**
 351  * ofdt_write - perform operations on the Open Firmware device tree
 352  *
 353  * @file: not used
 354  * @buf: command and arguments
 355  * @count: size of the command buffer
 356  * @off: not used
 357  *
 358  * Operations supported at this time are addition and removal of
 359  * whole nodes along with their properties.  Operations on individual
 360  * properties are not implemented (yet).
 361  */
 362 static ssize_t ofdt_write(struct file *file, const char __user *buf, size_t count,
 363                           loff_t *off)
 364 {
 365         int rv = 0;
 366         char *kbuf;
 367         char *tmp;
 368
 369         if (!(kbuf = kmalloc(count + 1, GFP_KERNEL))) {
 370                 rv = -ENOMEM;
 371                 goto out;
 372         }
 373         if (copy_from_user(kbuf, buf, count)) {
 374                 rv = -EFAULT;
 375                 goto out;
 376         }
 377
 378         kbuf[count] = '\0';
 379
 380         tmp = strchr(kbuf, ' ');
 381         if (!tmp) {
 382                 rv = -EINVAL;
 383                 goto out;
 384         }
 385         *tmp = '\0';
 386         tmp++;
 387
 388         if (!strcmp(kbuf, "add_node"))
 389                 rv = do_add_node(tmp, count - (tmp - kbuf));
 390         else if (!strcmp(kbuf, "remove_node"))
 391                 rv = do_remove_node(tmp);
 392         else if (!strcmp(kbuf, "add_property"))
 393                 rv = do_add_property(tmp, count - (tmp - kbuf));
 394         else if (!strcmp(kbuf, "remove_property"))
 395                 rv = do_remove_property(tmp, count - (tmp - kbuf));
 396         else if (!strcmp(kbuf, "update_property"))
 397                 rv = do_update_property(tmp, count - (tmp - kbuf));
 398         else
 399                 rv = -EINVAL;
 400 out:
 401         kfree(kbuf);
 402         return rv ? rv : count;
 403 }
 404
 405 static const struct file_operations ofdt_fops = {
 406         .write = ofdt_write,
 407         .llseek = noop_llseek,
 408 };
 409
 410 /* create /proc/powerpc/ofdt write-only by root */
 411 static int proc_ppc64_create_ofdt(void)
 412 {
 413         struct proc_dir_entry *ent;
 414
 415         ent = proc_create("powerpc/ofdt", S_IWUSR, NULL, &ofdt_fops);
 416         if (ent)
 417                 proc_set_size(ent, 0);
 418
 419         return 0;
 420 }
 421 machine_device_initcall(pseries, proc_ppc64_create_ofdt);