u-boot-brain/env/ext4.c
Jean-Jacques Hiblot 5efc0686ee fs: ext4: Add support for the creation of symbolic links
Re-use the functions used to write/create a file, to support creation of a
symbolic link.
The difference with a regular file are small:
- The inode mode is flagged with S_IFLNK instead of S_IFREG
- The ext2_dirent's filetype is FILETYPE_SYMLINK instead of FILETYPE_REG
- Instead of storing the content of a file in allocated blocks, the path
to the target is stored. And if the target's path is short enough, no block
is allocated and the target's path is stored in ext2_inode.b.symlink

As with regulars files, if a file/symlink with the same name exits, it is
unlinked first and then re-created.

Signed-off-by: Jean-Jacques Hiblot <jjhiblot@ti.com>
Reviewed-by: Tom Rini <trini@konsulko.com>
[trini: Fix ext4 env code]
Signed-off-by: Tom Rini <trini@konsulko.com>
2019-04-09 20:03:30 -04:00

133 lines
2.8 KiB
C

// SPDX-License-Identifier: GPL-2.0+
/*
* (c) Copyright 2016 by VRT Technology
*
* Author:
* Stuart Longland <stuartl@vrt.com.au>
*
* Based on FAT environment driver
* (c) Copyright 2011 by Tigris Elektronik GmbH
*
* Author:
* Maximilian Schwerin <mvs@tigris.de>
*
* and EXT4 filesystem implementation
* (C) Copyright 2011 - 2012 Samsung Electronics
* EXT4 filesystem implementation in Uboot by
* Uma Shankar <uma.shankar@samsung.com>
* Manjunatha C Achar <a.manjunatha@samsung.com>
*/
#include <common.h>
#include <command.h>
#include <environment.h>
#include <linux/stddef.h>
#include <malloc.h>
#include <memalign.h>
#include <search.h>
#include <errno.h>
#include <ext4fs.h>
#include <mmc.h>
#ifdef CONFIG_CMD_SAVEENV
static int env_ext4_save(void)
{
env_t env_new;
struct blk_desc *dev_desc = NULL;
disk_partition_t info;
int dev, part;
int err;
err = env_export(&env_new);
if (err)
return err;
part = blk_get_device_part_str(CONFIG_ENV_EXT4_INTERFACE,
CONFIG_ENV_EXT4_DEVICE_AND_PART,
&dev_desc, &info, 1);
if (part < 0)
return 1;
dev = dev_desc->devnum;
ext4fs_set_blk_dev(dev_desc, &info);
if (!ext4fs_mount(info.size)) {
printf("\n** Unable to use %s %s for saveenv **\n",
CONFIG_ENV_EXT4_INTERFACE,
CONFIG_ENV_EXT4_DEVICE_AND_PART);
return 1;
}
err = ext4fs_write(CONFIG_ENV_EXT4_FILE, (void *)&env_new,
sizeof(env_t), FILETYPE_REG);
ext4fs_close();
if (err == -1) {
printf("\n** Unable to write \"%s\" from %s%d:%d **\n",
CONFIG_ENV_EXT4_FILE, CONFIG_ENV_EXT4_INTERFACE, dev,
part);
return 1;
}
puts("done\n");
return 0;
}
#endif /* CONFIG_CMD_SAVEENV */
static int env_ext4_load(void)
{
ALLOC_CACHE_ALIGN_BUFFER(char, buf, CONFIG_ENV_SIZE);
struct blk_desc *dev_desc = NULL;
disk_partition_t info;
int dev, part;
int err;
loff_t off;
#ifdef CONFIG_MMC
if (!strcmp(CONFIG_ENV_EXT4_INTERFACE, "mmc"))
mmc_initialize(NULL);
#endif
part = blk_get_device_part_str(CONFIG_ENV_EXT4_INTERFACE,
CONFIG_ENV_EXT4_DEVICE_AND_PART,
&dev_desc, &info, 1);
if (part < 0)
goto err_env_relocate;
dev = dev_desc->devnum;
ext4fs_set_blk_dev(dev_desc, &info);
if (!ext4fs_mount(info.size)) {
printf("\n** Unable to use %s %s for loading the env **\n",
CONFIG_ENV_EXT4_INTERFACE,
CONFIG_ENV_EXT4_DEVICE_AND_PART);
goto err_env_relocate;
}
err = ext4_read_file(CONFIG_ENV_EXT4_FILE, buf, 0, CONFIG_ENV_SIZE,
&off);
ext4fs_close();
if (err == -1) {
printf("\n** Unable to read \"%s\" from %s%d:%d **\n",
CONFIG_ENV_EXT4_FILE, CONFIG_ENV_EXT4_INTERFACE, dev,
part);
goto err_env_relocate;
}
return env_import(buf, 1);
err_env_relocate:
set_default_env(NULL, 0);
return -EIO;
}
U_BOOT_ENV_LOCATION(ext4) = {
.location = ENVL_EXT4,
ENV_NAME("EXT4")
.load = env_ext4_load,
.save = env_save_ptr(env_ext4_save),
};