https://github.com/torvalds/linux
Tip revision: 41bccc98fb7931d63d03f326a746ac4d429c1dd3 authored by Linus Torvalds on 29 January 2024, 01:01:12 UTC
Linux 6.8-rc2
Linux 6.8-rc2
Tip revision: 41bccc9
fdtoverlay.c
// SPDX-License-Identifier: GPL-2.0-or-later
/*
* Copyright (c) 2017 Konsulko Group Inc. All rights reserved.
*
* Author:
* Pantelis Antoniou <pantelis.antoniou@konsulko.com>
*/
#include <assert.h>
#include <ctype.h>
#include <getopt.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <inttypes.h>
#include <libfdt.h>
#include "util.h"
#define BUF_INCREMENT 65536
/* Usage related data. */
static const char usage_synopsis[] =
"apply a number of overlays to a base blob\n"
" fdtoverlay <options> [<overlay.dtbo> [<overlay.dtbo>]]\n"
"\n"
USAGE_TYPE_MSG;
static const char usage_short_opts[] = "i:o:v" USAGE_COMMON_SHORT_OPTS;
static struct option const usage_long_opts[] = {
{"input", required_argument, NULL, 'i'},
{"output", required_argument, NULL, 'o'},
{"verbose", no_argument, NULL, 'v'},
USAGE_COMMON_LONG_OPTS,
};
static const char * const usage_opts_help[] = {
"Input base DT blob",
"Output DT blob",
"Verbose messages",
USAGE_COMMON_OPTS_HELP
};
int verbose = 0;
static void *apply_one(char *base, const char *overlay, size_t *buf_len,
const char *name)
{
char *tmp = NULL;
char *tmpo;
int ret;
/*
* We take a copies first, because a a failed apply can trash
* both the base blob and the overlay
*/
tmpo = xmalloc(fdt_totalsize(overlay));
do {
tmp = xrealloc(tmp, *buf_len);
ret = fdt_open_into(base, tmp, *buf_len);
if (ret) {
fprintf(stderr,
"\nFailed to make temporary copy: %s\n",
fdt_strerror(ret));
goto fail;
}
memcpy(tmpo, overlay, fdt_totalsize(overlay));
ret = fdt_overlay_apply(tmp, tmpo);
if (ret == -FDT_ERR_NOSPACE) {
*buf_len += BUF_INCREMENT;
}
} while (ret == -FDT_ERR_NOSPACE);
if (ret) {
fprintf(stderr, "\nFailed to apply '%s': %s\n",
name, fdt_strerror(ret));
goto fail;
}
free(base);
free(tmpo);
return tmp;
fail:
free(tmpo);
if (tmp)
free(tmp);
return NULL;
}
static int do_fdtoverlay(const char *input_filename,
const char *output_filename,
int argc, char *argv[])
{
char *blob = NULL;
char **ovblob = NULL;
size_t buf_len;
int i, ret = -1;
blob = utilfdt_read(input_filename, &buf_len);
if (!blob) {
fprintf(stderr, "\nFailed to read '%s'\n", input_filename);
goto out_err;
}
if (fdt_totalsize(blob) > buf_len) {
fprintf(stderr,
"\nBase blob is incomplete (%lu / %" PRIu32 " bytes read)\n",
(unsigned long)buf_len, fdt_totalsize(blob));
goto out_err;
}
/* allocate blob pointer array */
ovblob = xmalloc(sizeof(*ovblob) * argc);
memset(ovblob, 0, sizeof(*ovblob) * argc);
/* read and keep track of the overlay blobs */
for (i = 0; i < argc; i++) {
size_t ov_len;
ovblob[i] = utilfdt_read(argv[i], &ov_len);
if (!ovblob[i]) {
fprintf(stderr, "\nFailed to read '%s'\n", argv[i]);
goto out_err;
}
if (fdt_totalsize(ovblob[i]) > ov_len) {
fprintf(stderr,
"\nOverlay '%s' is incomplete (%lu / %" PRIu32 " bytes read)\n",
argv[i], (unsigned long)ov_len,
fdt_totalsize(ovblob[i]));
goto out_err;
}
}
buf_len = fdt_totalsize(blob);
/* apply the overlays in sequence */
for (i = 0; i < argc; i++) {
blob = apply_one(blob, ovblob[i], &buf_len, argv[i]);
if (!blob)
goto out_err;
}
fdt_pack(blob);
ret = utilfdt_write(output_filename, blob);
if (ret)
fprintf(stderr, "\nFailed to write '%s'\n",
output_filename);
out_err:
if (ovblob) {
for (i = 0; i < argc; i++) {
if (ovblob[i])
free(ovblob[i]);
}
free(ovblob);
}
free(blob);
return ret;
}
int main(int argc, char *argv[])
{
int opt, i;
char *input_filename = NULL;
char *output_filename = NULL;
while ((opt = util_getopt_long()) != EOF) {
switch (opt) {
case_USAGE_COMMON_FLAGS
case 'i':
input_filename = optarg;
break;
case 'o':
output_filename = optarg;
break;
case 'v':
verbose = 1;
break;
}
}
if (!input_filename)
usage("missing input file");
if (!output_filename)
usage("missing output file");
argv += optind;
argc -= optind;
if (argc <= 0)
usage("missing overlay file(s)");
if (verbose) {
printf("input = %s\n", input_filename);
printf("output = %s\n", output_filename);
for (i = 0; i < argc; i++)
printf("overlay[%d] = %s\n", i, argv[i]);
}
if (do_fdtoverlay(input_filename, output_filename, argc, argv))
return 1;
return 0;
}