libfdt/fdt_rw.c

   1 /*
   2  * libfdt - Flat Device Tree manipulation
   3  * Copyright (C) 2006 David Gibson, IBM Corporation.
   4  *
   5  * libfdt is dual licensed: you can use it either under the terms of
   6  * the GPL, or the BSD license, at your option.
   7  *
   8  *  a) This library is free software; you can redistribute it and/or
   9  *     modify it under the terms of the GNU General Public License as
  10  *     published by the Free Software Foundation; either version 2 of the
  11  *     License, or (at your option) any later version.
  12  *
  13  *     This library is distributed in the hope that it will be useful,
  14  *     but WITHOUT ANY WARRANTY; without even the implied warranty of
  15  *     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  16  *     GNU General Public License for more details.
  17  *
  18  *     You should have received a copy of the GNU General Public
  19  *     License along with this library; if not, write to the Free
  20  *     Software Foundation, Inc., 51 Franklin St, Fifth Floor, Boston,
  21  *     MA 02110-1301 USA
  22  *
  23  * Alternatively,
  24  *
  25  *  b) Redistribution and use in source and binary forms, with or
  26  *     without modification, are permitted provided that the following
  27  *     conditions are met:
  28  *
  29  *     1. Redistributions of source code must retain the above
  30  *        copyright notice, this list of conditions and the following
  31  *        disclaimer.
  32  *     2. Redistributions in binary form must reproduce the above
  33  *        copyright notice, this list of conditions and the following
  34  *        disclaimer in the documentation and/or other materials
  35  *        provided with the distribution.
  36  *
  37  *     THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND
  38  *     CONTRIBUTORS "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES,
  39  *     INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
  40  *     MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
  41  *     DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR
  42  *     CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
  43  *     SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
  44  *     NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
  45  *     LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  46  *     HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
  47  *     CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR
  48  *     OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE,
  49  *     EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  50  */
  51 #include "libfdt_env.h"
  52
  53 #ifndef USE_HOSTCC
  54 #include <fdt.h>
  55 #include <libfdt.h>
  56 #else
  57 #include "fdt_host.h"
  58 #endif
  59
  60 #include "libfdt_internal.h"
  61
  62 static int _blocks_misordered(const void *fdt,
  63                               int mem_rsv_size, int struct_size)
  64 {
  65         return (fdt_off_mem_rsvmap(fdt) < ALIGN(sizeof(struct fdt_header), 8))
  66                 || (fdt_off_dt_struct(fdt) <
  67                     (fdt_off_mem_rsvmap(fdt) + mem_rsv_size))
  68                 || (fdt_off_dt_strings(fdt) <
  69                     (fdt_off_dt_struct(fdt) + struct_size))
  70                 || (fdt_totalsize(fdt) <
  71                     (fdt_off_dt_strings(fdt) + fdt_size_dt_strings(fdt)));
  72 }
  73
  74 static int rw_check_header(void *fdt)
  75 {
  76         CHECK_HEADER(fdt);
  77
  78         if (fdt_version(fdt) < 17)
  79                 return -FDT_ERR_BADVERSION;
  80         if (_blocks_misordered(fdt, sizeof(struct fdt_reserve_entry),
  81                                fdt_size_dt_struct(fdt)))
  82                 return -FDT_ERR_BADLAYOUT;
  83         if (fdt_version(fdt) > 17)
  84                 fdt_set_version(fdt, 17);
  85
  86         return 0;
  87 }
  88
  89 #define RW_CHECK_HEADER(fdt) \
  90         { \
  91                 int err; \
  92                 if ((err = rw_check_header(fdt)) != 0) \
  93                         return err; \
  94         }
  95
  96 static inline int _blob_data_size(void *fdt)
  97 {
  98         return fdt_off_dt_strings(fdt) + fdt_size_dt_strings(fdt);
  99 }
 100
 101 static int _blob_splice(void *fdt, void *p, int oldlen, int newlen)
 102 {
 103         void *end = fdt + _blob_data_size(fdt);
 104
 105         if (((p + oldlen) < p) || ((p + oldlen) > end))
 106                 return -FDT_ERR_BADOFFSET;
 107         if ((end - oldlen + newlen) > (fdt + fdt_totalsize(fdt)))
 108                 return -FDT_ERR_NOSPACE;
 109         memmove(p + newlen, p + oldlen, end - p - oldlen);
 110         return 0;
 111 }
 112
 113 static int _blob_splice_mem_rsv(void *fdt, struct fdt_reserve_entry *p,
 114                                 int oldn, int newn)
 115 {
 116         int delta = (newn - oldn) * sizeof(*p);
 117         int err;
 118         err = _blob_splice(fdt, p, oldn * sizeof(*p), newn * sizeof(*p));
 119         if (err)
 120                 return err;
 121         fdt_set_off_dt_struct(fdt, fdt_off_dt_struct(fdt) + delta);
 122         fdt_set_off_dt_strings(fdt, fdt_off_dt_strings(fdt) + delta);
 123         return 0;
 124 }
 125
 126 static int _blob_splice_struct(void *fdt, void *p,
 127                                int oldlen, int newlen)
 128 {
 129         int delta = newlen - oldlen;
 130         int err;
 131
 132         if ((err = _blob_splice(fdt, p, oldlen, newlen)))
 133                 return err;
 134
 135         fdt_set_size_dt_struct(fdt, fdt_size_dt_struct(fdt) + delta);
 136         fdt_set_off_dt_strings(fdt, fdt_off_dt_strings(fdt) + delta);
 137         return 0;
 138 }
 139
 140 static int _blob_splice_string(void *fdt, int newlen)
 141 {
 142         void *p = fdt + fdt_off_dt_strings(fdt) + fdt_size_dt_strings(fdt);
 143         int err;
 144
 145         if ((err = _blob_splice(fdt, p, 0, newlen)))
 146                 return err;
 147
 148         fdt_set_size_dt_strings(fdt, fdt_size_dt_strings(fdt) + newlen);
 149         return 0;
 150 }
 151
 152 static int _find_add_string(void *fdt, const char *s)
 153 {
 154         char *strtab = (char *)fdt + fdt_off_dt_strings(fdt);
 155         const char *p;
 156         char *new;
 157         int len = strlen(s) + 1;
 158         int err;
 159
 160         p = _fdt_find_string(strtab, fdt_size_dt_strings(fdt), s);
 161         if (p)
 162                 /* found it */
 163                 return (p - strtab);
 164
 165         new = strtab + fdt_size_dt_strings(fdt);
 166         err = _blob_splice_string(fdt, len);
 167         if (err)
 168                 return err;
 169
 170         memcpy(new, s, len);
 171         return (new - strtab);
 172 }
 173
 174 int fdt_add_mem_rsv(void *fdt, uint64_t address, uint64_t size)
 175 {
 176         struct fdt_reserve_entry *re;
 177         int err;
 178
 179         if ((err = rw_check_header(fdt)))
 180                 return err;
 181
 182         re = _fdt_mem_rsv_w(fdt, fdt_num_mem_rsv(fdt));
 183         err = _blob_splice_mem_rsv(fdt, re, 0, 1);
 184         if (err)
 185                 return err;
 186
 187         re->address = cpu_to_fdt64(address);
 188         re->size = cpu_to_fdt64(size);
 189         return 0;
 190 }
 191
 192 int fdt_del_mem_rsv(void *fdt, int n)
 193 {
 194         struct fdt_reserve_entry *re = _fdt_mem_rsv_w(fdt, n);
 195         int err;
 196
 197         if ((err = rw_check_header(fdt)))
 198                 return err;
 199         if (n >= fdt_num_mem_rsv(fdt))
 200                 return -FDT_ERR_NOTFOUND;
 201
 202         err = _blob_splice_mem_rsv(fdt, re, 1, 0);
 203         if (err)
 204                 return err;
 205         return 0;
 206 }
 207
 208 static int _resize_property(void *fdt, int nodeoffset, const char *name, int len,
 209                             struct fdt_property **prop)
 210 {
 211         int oldlen;
 212         int err;
 213
 214         *prop = fdt_get_property_w(fdt, nodeoffset, name, &oldlen);
 215         if (! (*prop))
 216                 return oldlen;
 217
 218         if ((err = _blob_splice_struct(fdt, (*prop)->data,
 219                                        ALIGN(oldlen, FDT_TAGSIZE),
 220                                        ALIGN(len, FDT_TAGSIZE))))
 221                 return err;
 222
 223         (*prop)->len = cpu_to_fdt32(len);
 224         return 0;
 225 }
 226
 227 static int _add_property(void *fdt, int nodeoffset, const char *name, int len,
 228                          struct fdt_property **prop)
 229 {
 230         uint32_t tag;
 231         int proplen;
 232         int nextoffset;
 233         int namestroff;
 234         int err;
 235
 236         tag = fdt_next_tag(fdt, nodeoffset, &nextoffset);
 237         if (tag != FDT_BEGIN_NODE)
 238                 return -FDT_ERR_BADOFFSET;
 239
 240         namestroff = _find_add_string(fdt, name);
 241         if (namestroff < 0)
 242                 return namestroff;
 243
 244         *prop = _fdt_offset_ptr_w(fdt, nextoffset);
 245         proplen = sizeof(**prop) + ALIGN(len, FDT_TAGSIZE);
 246
 247         err = _blob_splice_struct(fdt, *prop, 0, proplen);
 248         if (err)
 249                 return err;
 250
 251         (*prop)->tag = cpu_to_fdt32(FDT_PROP);
 252         (*prop)->nameoff = cpu_to_fdt32(namestroff);
 253         (*prop)->len = cpu_to_fdt32(len);
 254         return 0;
 255 }
 256
 257 int fdt_set_name(void *fdt, int nodeoffset, const char *name)
 258 {
 259         char *namep;
 260         int oldlen, newlen;
 261         int err;
 262
 263         if ((err = rw_check_header(fdt)))
 264                 return err;
 265
 266         namep = (char *)fdt_get_name(fdt, nodeoffset, &oldlen);
 267         if (!namep)
 268                 return oldlen;
 269
 270         newlen = strlen(name);
 271
 272         err = _blob_splice_struct(fdt, namep, ALIGN(oldlen+1, FDT_TAGSIZE),
 273                                   ALIGN(newlen+1, FDT_TAGSIZE));
 274         if (err)
 275                 return err;
 276
 277         memcpy(namep, name, newlen+1);
 278         return 0;
 279 }
 280
 281 int fdt_setprop(void *fdt, int nodeoffset, const char *name,
 282                 const void *val, int len)
 283 {
 284         struct fdt_property *prop;
 285         int err;
 286
 287         if ((err = rw_check_header(fdt)))
 288                 return err;
 289
 290         err = _resize_property(fdt, nodeoffset, name, len, &prop);
 291         if (err == -FDT_ERR_NOTFOUND)
 292                 err = _add_property(fdt, nodeoffset, name, len, &prop);
 293         if (err)
 294                 return err;
 295
 296         memcpy(prop->data, val, len);
 297         return 0;
 298 }
 299
 300 int fdt_delprop(void *fdt, int nodeoffset, const char *name)
 301 {
 302         struct fdt_property *prop;
 303         int len, proplen;
 304
 305         RW_CHECK_HEADER(fdt);
 306
 307         prop = fdt_get_property_w(fdt, nodeoffset, name, &len);
 308         if (! prop)
 309                 return len;
 310
 311         proplen = sizeof(*prop) + ALIGN(len, FDT_TAGSIZE);
 312         return _blob_splice_struct(fdt, prop, proplen, 0);
 313 }
 314
 315 int fdt_add_subnode_namelen(void *fdt, int parentoffset,
 316                             const char *name, int namelen)
 317 {
 318         struct fdt_node_header *nh;
 319         int offset, nextoffset;
 320         int nodelen;
 321         int err;
 322         uint32_t tag;
 323         uint32_t *endtag;
 324
 325         RW_CHECK_HEADER(fdt);
 326
 327         offset = fdt_subnode_offset_namelen(fdt, parentoffset, name, namelen);
 328         if (offset >= 0)
 329                 return -FDT_ERR_EXISTS;
 330         else if (offset != -FDT_ERR_NOTFOUND)
 331                 return offset;
 332
 333         /* Try to place the new node after the parent's properties */
 334         fdt_next_tag(fdt, parentoffset, &nextoffset); /* skip the BEGIN_NODE */
 335         do {
 336                 offset = nextoffset;
 337                 tag = fdt_next_tag(fdt, offset, &nextoffset);
 338         } while ((tag == FDT_PROP) || (tag == FDT_NOP));
 339
 340         nh = _fdt_offset_ptr_w(fdt, offset);
 341         nodelen = sizeof(*nh) + ALIGN(namelen+1, FDT_TAGSIZE) + FDT_TAGSIZE;
 342
 343         err = _blob_splice_struct(fdt, nh, 0, nodelen);
 344         if (err)
 345                 return err;
 346
 347         nh->tag = cpu_to_fdt32(FDT_BEGIN_NODE);
 348         memset(nh->name, 0, ALIGN(namelen+1, FDT_TAGSIZE));
 349         memcpy(nh->name, name, namelen);
 350         endtag = (uint32_t *)((void *)nh + nodelen - FDT_TAGSIZE);
 351         *endtag = cpu_to_fdt32(FDT_END_NODE);
 352
 353         return offset;
 354 }
 355
 356 int fdt_add_subnode(void *fdt, int parentoffset, const char *name)
 357 {
 358         return fdt_add_subnode_namelen(fdt, parentoffset, name, strlen(name));
 359 }
 360
 361 int fdt_del_node(void *fdt, int nodeoffset)
 362 {
 363         int endoffset;
 364
 365         RW_CHECK_HEADER(fdt);
 366
 367         endoffset = _fdt_node_end_offset(fdt, nodeoffset);
 368         if (endoffset < 0)
 369                 return endoffset;
 370
 371         return _blob_splice_struct(fdt, _fdt_offset_ptr_w(fdt, nodeoffset),
 372                                    endoffset - nodeoffset, 0);
 373 }
 374
 375 static void _packblocks(const void *fdt, void *buf,
 376                        int mem_rsv_size, int struct_size)
 377 {
 378         int mem_rsv_off, struct_off, strings_off;
 379
 380         mem_rsv_off = ALIGN(sizeof(struct fdt_header), 8);
 381         struct_off = mem_rsv_off + mem_rsv_size;
 382         strings_off = struct_off + struct_size;
 383
 384         memmove(buf + mem_rsv_off, fdt + fdt_off_mem_rsvmap(fdt), mem_rsv_size);
 385         fdt_set_off_mem_rsvmap(buf, mem_rsv_off);
 386
 387         memmove(buf + struct_off, fdt + fdt_off_dt_struct(fdt), struct_size);
 388         fdt_set_off_dt_struct(buf, struct_off);
 389         fdt_set_size_dt_struct(buf, struct_size);
 390
 391         memmove(buf + strings_off, fdt + fdt_off_dt_strings(fdt),
 392                 fdt_size_dt_strings(fdt));
 393         fdt_set_off_dt_strings(buf, strings_off);
 394         fdt_set_size_dt_strings(buf, fdt_size_dt_strings(fdt));
 395 }
 396
 397 int fdt_open_into(const void *fdt, void *buf, int bufsize)
 398 {
 399         int err;
 400         int mem_rsv_size, struct_size;
 401         int newsize;
 402         void *tmp;
 403
 404         CHECK_HEADER(fdt);
 405
 406         mem_rsv_size = (fdt_num_mem_rsv(fdt)+1)
 407                 * sizeof(struct fdt_reserve_entry);
 408
 409         if (fdt_version(fdt) >= 17) {
 410                 struct_size = fdt_size_dt_struct(fdt);
 411         } else {
 412                 struct_size = 0;
 413                 while (fdt_next_tag(fdt, struct_size, &struct_size) != FDT_END)
 414                         ;
 415         }
 416
 417         if (!_blocks_misordered(fdt, mem_rsv_size, struct_size)) {
 418                 /* no further work necessary */
 419                 err = fdt_move(fdt, buf, bufsize);
 420                 if (err)
 421                         return err;
 422                 fdt_set_version(buf, 17);
 423                 fdt_set_size_dt_struct(buf, struct_size);
 424                 fdt_set_totalsize(buf, bufsize);
 425                 return 0;
 426         }
 427
 428         /* Need to reorder */
 429         newsize = ALIGN(sizeof(struct fdt_header), 8) + mem_rsv_size
 430                 + struct_size + fdt_size_dt_strings(fdt);
 431
 432         if (bufsize < newsize)
 433                 return -FDT_ERR_NOSPACE;
 434
 435         if (((buf + newsize) <= fdt)
 436             || (buf >= (fdt + fdt_totalsize(fdt)))) {
 437                 tmp = buf;
 438         } else {
 439                 tmp = (void *)fdt + fdt_totalsize(fdt);
 440                 if ((tmp + newsize) > (buf + bufsize))
 441                         return -FDT_ERR_NOSPACE;
 442         }
 443
 444         _packblocks(fdt, tmp, mem_rsv_size, struct_size);
 445         memmove(buf, tmp, newsize);
 446
 447         fdt_set_magic(buf, FDT_MAGIC);
 448         fdt_set_totalsize(buf, bufsize);
 449         fdt_set_version(buf, 17);
 450         fdt_set_last_comp_version(buf, 16);
 451         fdt_set_boot_cpuid_phys(buf, fdt_boot_cpuid_phys(fdt));
 452
 453         return 0;
 454 }
 455
 456 int fdt_pack(void *fdt)
 457 {
 458         int mem_rsv_size;
 459         int err;
 460
 461         err = rw_check_header(fdt);
 462         if (err)
 463                 return err;
 464
 465         mem_rsv_size = (fdt_num_mem_rsv(fdt)+1)
 466                 * sizeof(struct fdt_reserve_entry);
 467         _packblocks(fdt, fdt, mem_rsv_size, fdt_size_dt_struct(fdt));
 468         fdt_set_totalsize(fdt, _blob_data_size(fdt));
 469
 470         return 0;
 471 }