95 lines
2.1 KiB
C
95 lines
2.1 KiB
C
// SPDX-License-Identifier: GPL-2.0
|
|
/*
|
|
* SMB root file system support
|
|
*
|
|
* Copyright (c) 2019 Paulo Alcantara <palcantara@suse.de>
|
|
*/
|
|
#include <linux/init.h>
|
|
#include <linux/fs.h>
|
|
#include <linux/types.h>
|
|
#include <linux/ctype.h>
|
|
#include <linux/string.h>
|
|
#include <linux/root_dev.h>
|
|
#include <linux/kernel.h>
|
|
#include <linux/in.h>
|
|
#include <linux/inet.h>
|
|
#include <net/ipconfig.h>
|
|
|
|
#define DEFAULT_MNT_OPTS \
|
|
"vers=1.0,cifsacl,mfsymlinks,rsize=1048576,wsize=65536,uid=0,gid=0," \
|
|
"hard,rootfs"
|
|
|
|
static char root_dev[2048] __initdata = "";
|
|
static char root_opts[1024] __initdata = DEFAULT_MNT_OPTS;
|
|
|
|
static __be32 __init parse_srvaddr(char *start, char *end)
|
|
{
|
|
/* TODO: ipv6 support */
|
|
char addr[sizeof("aaa.bbb.ccc.ddd")];
|
|
int i = 0;
|
|
|
|
while (start < end && i < sizeof(addr) - 1) {
|
|
if (isdigit(*start) || *start == '.')
|
|
addr[i++] = *start;
|
|
start++;
|
|
}
|
|
addr[i] = '\0';
|
|
return in_aton(addr);
|
|
}
|
|
|
|
/* cifsroot=//<server-ip>/<share>[,options] */
|
|
static int __init cifs_root_setup(char *line)
|
|
{
|
|
char *s;
|
|
int len;
|
|
__be32 srvaddr = htonl(INADDR_NONE);
|
|
|
|
ROOT_DEV = Root_CIFS;
|
|
|
|
if (strlen(line) > 3 && line[0] == '/' && line[1] == '/') {
|
|
s = strchr(&line[2], '/');
|
|
if (!s || s[1] == '\0')
|
|
return 1;
|
|
|
|
/* make s point to ',' or '\0' at end of line */
|
|
s = strchrnul(s, ',');
|
|
/* len is strlen(unc) + '\0' */
|
|
len = s - line + 1;
|
|
if (len > sizeof(root_dev)) {
|
|
pr_err("Root-CIFS: UNC path too long\n");
|
|
return 1;
|
|
}
|
|
strscpy(root_dev, line, len);
|
|
srvaddr = parse_srvaddr(&line[2], s);
|
|
if (*s) {
|
|
int n = snprintf(root_opts,
|
|
sizeof(root_opts), "%s,%s",
|
|
DEFAULT_MNT_OPTS, s + 1);
|
|
if (n >= sizeof(root_opts)) {
|
|
pr_err("Root-CIFS: mount options string too long\n");
|
|
root_opts[sizeof(root_opts)-1] = '\0';
|
|
return 1;
|
|
}
|
|
}
|
|
}
|
|
|
|
root_server_addr = srvaddr;
|
|
|
|
return 1;
|
|
}
|
|
|
|
__setup("cifsroot=", cifs_root_setup);
|
|
|
|
int __init cifs_root_data(char **dev, char **opts)
|
|
{
|
|
if (!root_dev[0] || root_server_addr == htonl(INADDR_NONE)) {
|
|
pr_err("Root-CIFS: no SMB server address\n");
|
|
return -1;
|
|
}
|
|
|
|
*dev = root_dev;
|
|
*opts = root_opts;
|
|
|
|
return 0;
|
|
}
|