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// SPDX-License-Identifier: (GPL-2.0-or-later OR BSD-2-Clause)
/*
* libfdt - Flat Device Tree manipulation
* Copyright (C) 2006 David Gibson, IBM Corporation.
*/
#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_probe_(void *fdt)
{
if (can_assume(VALID_DTB))
return 0;
FDT_RO_PROBE(fdt);
if (!can_assume(LATEST) && 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 (!can_assume(LATEST) && fdt_version(fdt) > 17)
fdt_set_version(fdt, 17);
return 0;
}
#define FDT_RW_PROBE(fdt) \
{ \
int err_; \
if ((err_ = fdt_rw_probe_(fdt)) != 0) \
return err_; \
}
static inline unsigned 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;
unsigned int dsize = fdt_data_size_(fdt);
size_t soff = p - (char *)fdt;
if ((oldlen < 0) || (soff + oldlen < soff) || (soff + oldlen > dsize))
return -FDT_ERR_BADOFFSET;
if ((p < (char *)fdt) || (dsize + newlen < (unsigned)oldlen))
return -FDT_ERR_BADOFFSET;
if (dsize - oldlen + newlen > fdt_totalsize(fdt))
return -FDT_ERR_NOSPACE;
memmove(p + newlen, p + oldlen, ((char *)fdt + dsize) - (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;
}
/* Must only be used to roll back in case of error */
static void fdt_del_last_string_(void *fdt, const char *s)
{
int newlen = strlen(s) + 1;
fdt_set_size_dt_strings(fdt, fdt_size_dt_strings(fdt) - newlen);
}
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;
}
/**
* fdt_find_add_string_() - Find or allocate a string
*
* @fdt: pointer to the device tree to check/adjust
* @s: string to find/add
* @allocated: Set to 0 if the string was found, 1 if not found and so
* allocated. Ignored if can_assume(NO_ROLLBACK)
* @return offset of string in the string table (whether found or added)
*/
static int fdt_find_add_string_(void *fdt, const char *s, int *allocated)
{
char *strtab = (char *)fdt + fdt_off_dt_strings(fdt);
const char *p;
char *new;
int len = strlen(s) + 1;
int err;
if (!can_assume(NO_ROLLBACK))
*allocated = 0;
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;
if (!can_assume(NO_ROLLBACK))
*allocated = 1;
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_PROBE(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);
FDT_RW_PROBE(fdt);
if (n >= fdt_num_mem_rsv(fdt))
return -FDT_ERR_NOTFOUND;
return fdt_splice_mem_rsv_(fdt, re, 1, 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;
int allocated;
if ((nextoffset = fdt_check_node_offset_(fdt, nodeoffset)) < 0)
return nextoffset;
namestroff = fdt_find_add_string_(fdt, name, &allocated);
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) {
/* Delete the string if we failed to add it */
if (!can_assume(NO_ROLLBACK) && allocated)
fdt_del_last_string_(fdt, name);
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_PROBE(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_placeholder(void *fdt, int nodeoffset, const char *name,
int len, void **prop_data)
{
struct fdt_property *prop;
int err;
FDT_RW_PROBE(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;
*prop_data = prop->data;
return 0;
}
int fdt_setprop(void *fdt, int nodeoffset, const char *name,
const void *val, int len)
{
void *prop_data;
int err;
err = fdt_setprop_placeholder(fdt, nodeoffset, name, len, &prop_data);
if (err)
return err;
if (len)
memcpy(prop_data, val, len);
return 0;
}
int fdt_appendprop(void *fdt, int nodeoffset, const char *name,
const void *val, int len)
{
struct fdt_property *prop;
int err, oldlen, newlen;
FDT_RW_PROBE(fdt);
prop = fdt_get_property_w(fdt, nodeoffset, name, &oldlen);
if (prop) {
newlen = len + oldlen;
err = fdt_splice_struct_(fdt, prop->data,
FDT_TAGALIGN(oldlen),
FDT_TAGALIGN(newlen));
if (err)
return err;
prop->len = cpu_to_fdt32(newlen);
memcpy(prop->data + oldlen, val, len);
} else {
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_PROBE(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;
fdt32_t *endtag;
FDT_RW_PROBE(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 = (fdt32_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_PROBE(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_RO_PROBE(fdt);
mem_rsv_size = (fdt_num_mem_rsv(fdt)+1)
* sizeof(struct fdt_reserve_entry);
if (can_assume(LATEST) || fdt_version(fdt) >= 17) {
struct_size = fdt_size_dt_struct(fdt);
} else if (fdt_version(fdt) == 16) {
struct_size = 0;
while (fdt_next_tag(fdt, struct_size, &struct_size) != FDT_END)
;
if (struct_size < 0)
return struct_size;
} else {
return -FDT_ERR_BADVERSION;
}
if (can_assume(LIBFDT_ORDER) ||
!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_PROBE(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;
}
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