grub/grub-core/lib/dtc/libfdt/fdt_rw.c

/*
 * libfdt - Flat Device Tree manipulation
 * Copyright (C) 2006 David Gibson, IBM Corporation.
 *
 * libfdt is dual licensed: you can use it either under the terms of
 * the GPL, or the BSD license, at your option.
 *
 *  a) This library is free software; you can redistribute it and/or
 *     modify it under the terms of the GNU General Public License as
 *     published by the Free Software Foundation; either version 2 of the
 *     License, or (at your option) any later version.
 *
 *     This library is distributed in the hope that it will be useful,
 *     but WITHOUT ANY WARRANTY; without even the implied warranty of
 *     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 *     GNU General Public License for more details.
 *
 *     You should have received a copy of the GNU General Public
 *     License along with this library; if not, write to the Free
 *     Software Foundation, Inc., 51 Franklin St, Fifth Floor, Boston,
 *     MA 02110-1301 USA
 *
 * Alternatively,
 *
 *  b) Redistribution and use in source and binary forms, with or
 *     without modification, are permitted provided that the following
 *     conditions are met:
 *
 *     1. Redistributions of source code must retain the above
 *        copyright notice, this list of conditions and the following
 *        disclaimer.
 *     2. Redistributions in binary form must reproduce the above
 *        copyright notice, this list of conditions and the following
 *        disclaimer in the documentation and/or other materials
 *        provided with the distribution.
 *
 *     THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND
 *     CONTRIBUTORS "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES,
 *     INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
 *     MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
 *     DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR
 *     CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
 *     SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
 *     NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
 *     LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 *     HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
 *     CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR
 *     OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE,
 *     EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */
#include "libfdt_env.h"

#include <fdt.h>
#include <libfdt.h>

#include "libfdt_internal.h"

static int
_fdt_blocks_misordered (const void *fdt, int mem_rsv_size, int struct_size)
{
  return (fdt_off_mem_rsvmap (fdt) <
	  FDT_ALIGN (sizeof (struct fdt_header), 8))
    || (fdt_off_dt_struct (fdt) < (fdt_off_mem_rsvmap (fdt) + mem_rsv_size))
    || (fdt_off_dt_strings (fdt) < (fdt_off_dt_struct (fdt) + struct_size))
    || (fdt_totalsize (fdt) <
	(fdt_off_dt_strings (fdt) + fdt_size_dt_strings (fdt)));
}

static int
_fdt_rw_check_header (void *fdt)
{
  FDT_CHECK_HEADER (fdt);

  if (fdt_version (fdt) < 17)
    return -FDT_ERR_BADVERSION;
  if (_fdt_blocks_misordered (fdt, sizeof (struct fdt_reserve_entry),
			      fdt_size_dt_struct (fdt)))
    return -FDT_ERR_BADLAYOUT;
  if (fdt_version (fdt) > 17)
    fdt_set_version (fdt, 17);

  return 0;
}

#define FDT_RW_CHECK_HEADER(fdt) \
	{ \
		int err; \
		if ((err = _fdt_rw_check_header(fdt)) != 0) \
			return err; \
	}

static inline int
_fdt_data_size (void *fdt)
{
  return fdt_off_dt_strings (fdt) + fdt_size_dt_strings (fdt);
}

static int
_fdt_splice (void *fdt, void *splicepoint, int oldlen, int newlen)
{
  char *p = splicepoint;
  char *end = (char *) fdt + _fdt_data_size (fdt);

  if (((p + oldlen) < p) || ((p + oldlen) > end))
    return -FDT_ERR_BADOFFSET;
  if ((end - oldlen + newlen) > ((char *) fdt + fdt_totalsize (fdt)))
    return -FDT_ERR_NOSPACE;
  memmove (p + newlen, p + oldlen, end - p - oldlen);
  return 0;
}

static int
_fdt_splice_mem_rsv (void *fdt, struct fdt_reserve_entry *p,
		     int oldn, int newn)
{
  int delta = (newn - oldn) * sizeof (*p);
  int err;
  err = _fdt_splice (fdt, p, oldn * sizeof (*p), newn * sizeof (*p));
  if (err)
    return err;
  fdt_set_off_dt_struct (fdt, fdt_off_dt_struct (fdt) + delta);
  fdt_set_off_dt_strings (fdt, fdt_off_dt_strings (fdt) + delta);
  return 0;
}

static int
_fdt_splice_struct (void *fdt, void *p, int oldlen, int newlen)
{
  int delta = newlen - oldlen;
  int err;

  if ((err = _fdt_splice (fdt, p, oldlen, newlen)))
    return err;

  fdt_set_size_dt_struct (fdt, fdt_size_dt_struct (fdt) + delta);
  fdt_set_off_dt_strings (fdt, fdt_off_dt_strings (fdt) + delta);
  return 0;
}

static int
_fdt_splice_string (void *fdt, int newlen)
{
  void *p = (char *) fdt
    + fdt_off_dt_strings (fdt) + fdt_size_dt_strings (fdt);
  int err;

  if ((err = _fdt_splice (fdt, p, 0, newlen)))
    return err;

  fdt_set_size_dt_strings (fdt, fdt_size_dt_strings (fdt) + newlen);
  return 0;
}

static int
_fdt_find_add_string (void *fdt, const char *s)
{
  char *strtab = (char *) fdt + fdt_off_dt_strings (fdt);
  const char *p;
  char *new;
  int len = strlen (s) + 1;
  int err;

  p = _fdt_find_string (strtab, fdt_size_dt_strings (fdt), s);
  if (p)
    /* found it */
    return (p - strtab);

  new = strtab + fdt_size_dt_strings (fdt);
  err = _fdt_splice_string (fdt, len);
  if (err)
    return err;

  memcpy (new, s, len);
  return (new - strtab);
}

int
fdt_add_mem_rsv (void *fdt, uint64_t address, uint64_t size)
{
  struct fdt_reserve_entry *re;
  int err;

  FDT_RW_CHECK_HEADER (fdt);

  re = _fdt_mem_rsv_w (fdt, fdt_num_mem_rsv (fdt));
  err = _fdt_splice_mem_rsv (fdt, re, 0, 1);
  if (err)
    return err;

  re->address = cpu_to_fdt64 (address);
  re->size = cpu_to_fdt64 (size);
  return 0;
}

int
fdt_del_mem_rsv (void *fdt, int n)
{
  struct fdt_reserve_entry *re = _fdt_mem_rsv_w (fdt, n);
  int err;

  FDT_RW_CHECK_HEADER (fdt);

  if (n >= fdt_num_mem_rsv (fdt))
    return -FDT_ERR_NOTFOUND;

  err = _fdt_splice_mem_rsv (fdt, re, 1, 0);
  if (err)
    return err;
  return 0;
}

static int
_fdt_resize_property (void *fdt, int nodeoffset, const char *name,
		      int len, struct fdt_property **prop)
{
  int oldlen;
  int err;

  *prop = fdt_get_property_w (fdt, nodeoffset, name, &oldlen);
  if (!(*prop))
    return oldlen;

  if ((err = _fdt_splice_struct (fdt, (*prop)->data, FDT_TAGALIGN (oldlen),
				 FDT_TAGALIGN (len))))
    return err;

  (*prop)->len = cpu_to_fdt32 (len);
  return 0;
}

static int
_fdt_add_property (void *fdt, int nodeoffset, const char *name,
		   int len, struct fdt_property **prop)
{
  int proplen;
  int nextoffset;
  int namestroff;
  int err;

  if ((nextoffset = _fdt_check_node_offset (fdt, nodeoffset)) < 0)
    return nextoffset;

  namestroff = _fdt_find_add_string (fdt, name);
  if (namestroff < 0)
    return namestroff;

  *prop = _fdt_offset_ptr_w (fdt, nextoffset);
  proplen = sizeof (**prop) + FDT_TAGALIGN (len);

  err = _fdt_splice_struct (fdt, *prop, 0, proplen);
  if (err)
    return err;

  (*prop)->tag = cpu_to_fdt32 (FDT_PROP);
  (*prop)->nameoff = cpu_to_fdt32 (namestroff);
  (*prop)->len = cpu_to_fdt32 (len);
  return 0;
}

int
fdt_set_name (void *fdt, int nodeoffset, const char *name)
{
  char *namep;
  int oldlen, newlen;
  int err;

  FDT_RW_CHECK_HEADER (fdt);

  namep = (char *) (uintptr_t) fdt_get_name (fdt, nodeoffset, &oldlen);
  if (!namep)
    return oldlen;

  newlen = strlen (name);

  err = _fdt_splice_struct (fdt, namep, FDT_TAGALIGN (oldlen + 1),
			    FDT_TAGALIGN (newlen + 1));
  if (err)
    return err;

  memcpy (namep, name, newlen + 1);
  return 0;
}

int
fdt_setprop (void *fdt, int nodeoffset, const char *name,
	     const void *val, int len)
{
  struct fdt_property *prop;
  int err;

  FDT_RW_CHECK_HEADER (fdt);

  err = _fdt_resize_property (fdt, nodeoffset, name, len, &prop);
  if (err == -FDT_ERR_NOTFOUND)
    err = _fdt_add_property (fdt, nodeoffset, name, len, &prop);
  if (err)
    return err;

  memcpy (prop->data, val, len);
  return 0;
}

int
fdt_delprop (void *fdt, int nodeoffset, const char *name)
{
  struct fdt_property *prop;
  int len, proplen;

  FDT_RW_CHECK_HEADER (fdt);

  prop = fdt_get_property_w (fdt, nodeoffset, name, &len);
  if (!prop)
    return len;

  proplen = sizeof (*prop) + FDT_TAGALIGN (len);
  return _fdt_splice_struct (fdt, prop, proplen, 0);
}

int
fdt_add_subnode_namelen (void *fdt, int parentoffset,
			 const char *name, int namelen)
{
  struct fdt_node_header *nh;
  int offset, nextoffset;
  int nodelen;
  int err;
  uint32_t tag;
  uint32_t *endtag;

  FDT_RW_CHECK_HEADER (fdt);

  offset = fdt_subnode_offset_namelen (fdt, parentoffset, name, namelen);
  if (offset >= 0)
    return -FDT_ERR_EXISTS;
  else if (offset != -FDT_ERR_NOTFOUND)
    return offset;

  /* Try to place the new node after the parent's properties */
  fdt_next_tag (fdt, parentoffset, &nextoffset);	/* skip the BEGIN_NODE */
  do
    {
      offset = nextoffset;
      tag = fdt_next_tag (fdt, offset, &nextoffset);
    }
  while ((tag == FDT_PROP) || (tag == FDT_NOP));

  nh = _fdt_offset_ptr_w (fdt, offset);
  nodelen = sizeof (*nh) + FDT_TAGALIGN (namelen + 1) + FDT_TAGSIZE;

  err = _fdt_splice_struct (fdt, nh, 0, nodelen);
  if (err)
    return err;

  nh->tag = cpu_to_fdt32 (FDT_BEGIN_NODE);
  memset (nh->name, 0, FDT_TAGALIGN (namelen + 1));
  memcpy (nh->name, name, namelen);
  endtag = (uint32_t *) ((char *) nh + nodelen - FDT_TAGSIZE);
  *endtag = cpu_to_fdt32 (FDT_END_NODE);

  return offset;
}

int
fdt_add_subnode (void *fdt, int parentoffset, const char *name)
{
  return fdt_add_subnode_namelen (fdt, parentoffset, name, strlen (name));
}

int
fdt_del_node (void *fdt, int nodeoffset)
{
  int endoffset;

  FDT_RW_CHECK_HEADER (fdt);

  endoffset = _fdt_node_end_offset (fdt, nodeoffset);
  if (endoffset < 0)
    return endoffset;

  return _fdt_splice_struct (fdt, _fdt_offset_ptr_w (fdt, nodeoffset),
			     endoffset - nodeoffset, 0);
}

static void
_fdt_packblocks (const char *old, char *new,
		 int mem_rsv_size, int struct_size)
{
  int mem_rsv_off, struct_off, strings_off;

  mem_rsv_off = FDT_ALIGN (sizeof (struct fdt_header), 8);
  struct_off = mem_rsv_off + mem_rsv_size;
  strings_off = struct_off + struct_size;

  memmove (new + mem_rsv_off, old + fdt_off_mem_rsvmap (old), mem_rsv_size);
  fdt_set_off_mem_rsvmap (new, mem_rsv_off);

  memmove (new + struct_off, old + fdt_off_dt_struct (old), struct_size);
  fdt_set_off_dt_struct (new, struct_off);
  fdt_set_size_dt_struct (new, struct_size);

  memmove (new + strings_off, old + fdt_off_dt_strings (old),
	   fdt_size_dt_strings (old));
  fdt_set_off_dt_strings (new, strings_off);
  fdt_set_size_dt_strings (new, fdt_size_dt_strings (old));
}

int
fdt_open_into (const void *fdt, void *buf, int bufsize)
{
  int err;
  int mem_rsv_size, struct_size;
  int newsize;
  const char *fdtstart = fdt;
  const char *fdtend = fdtstart + fdt_totalsize (fdt);
  char *tmp;

  FDT_CHECK_HEADER (fdt);

  mem_rsv_size = (fdt_num_mem_rsv (fdt) + 1)
    * sizeof (struct fdt_reserve_entry);

  if (fdt_version (fdt) >= 17)
    {
      struct_size = fdt_size_dt_struct (fdt);
    }
  else
    {
      struct_size = 0;
      while (fdt_next_tag (fdt, struct_size, &struct_size) != FDT_END)
	;
      if (struct_size < 0)
	return struct_size;
    }

  if (!_fdt_blocks_misordered (fdt, mem_rsv_size, struct_size))
    {
      /* no further work necessary */
      err = fdt_move (fdt, buf, bufsize);
      if (err)
	return err;
      fdt_set_version (buf, 17);
      fdt_set_size_dt_struct (buf, struct_size);
      fdt_set_totalsize (buf, bufsize);
      return 0;
    }

  /* Need to reorder */
  newsize = FDT_ALIGN (sizeof (struct fdt_header), 8) + mem_rsv_size
    + struct_size + fdt_size_dt_strings (fdt);

  if (bufsize < newsize)
    return -FDT_ERR_NOSPACE;

  /* First attempt to build converted tree at beginning of buffer */
  tmp = buf;
  /* But if that overlaps with the old tree... */
  if (((tmp + newsize) > fdtstart) && (tmp < fdtend))
    {
      /* Try right after the old tree instead */
      tmp = (char *) (uintptr_t) fdtend;
      if ((tmp + newsize) > ((char *) buf + bufsize))
	return -FDT_ERR_NOSPACE;
    }

  _fdt_packblocks (fdt, tmp, mem_rsv_size, struct_size);
  memmove (buf, tmp, newsize);

  fdt_set_magic (buf, FDT_MAGIC);
  fdt_set_totalsize (buf, bufsize);
  fdt_set_version (buf, 17);
  fdt_set_last_comp_version (buf, 16);
  fdt_set_boot_cpuid_phys (buf, fdt_boot_cpuid_phys (fdt));

  return 0;
}

int
fdt_pack (void *fdt)
{
  int mem_rsv_size;

  FDT_RW_CHECK_HEADER (fdt);

  mem_rsv_size = (fdt_num_mem_rsv (fdt) + 1)
    * sizeof (struct fdt_reserve_entry);
  _fdt_packblocks (fdt, fdt, mem_rsv_size, fdt_size_dt_struct (fdt));
  fdt_set_totalsize (fdt, _fdt_data_size (fdt));

  return 0;
}