SliTaz Repositories

     1.1 --- /dev/null	Thu Jan 01 00:00:00 1970 +0000
     1.2 +++ b/linux/stuff/linux-subroot.u2	Wed Dec 18 15:14:49 2013 +0000
     1.3 @@ -0,0 +1,61 @@
     1.4 +Allow to boot on any directories in a filesystem. You will be able to :
     1.5 +- have several distributions in one partition
     1.6 +- use effectively the disk space between several distributions
     1.7 +- deduplicate files across several distributions
     1.8 +
     1.9 +The bad news : you can't remount /
    1.10 +
    1.11 +example: bzImage rw root=/dev/sda1:/var/os/slitaz-4.0 screen=1024x768x24
    1.12 +
    1.13 +Signed-off-by: Pascal Bellard <pascal.bellard@slitaz.org>
    1.14 +--- linux-3.2.40/Documentation/kernel-parameters.txt
    1.15 ++++ linux-3.2.40/Documentation/kernel-parameters.txt
    1.16 +@@ -2304,8 +2304,9 @@
    1.17 + 
    1.18 + 	ro		[KNL] Mount root device read-only on boot
    1.19 + 
    1.20 +-	root=		[KNL] Root filesystem
    1.21 ++	root=		[KNL] Root filesystem and root directory
    1.22 + 			See name_to_dev_t comment in init/do_mounts.c.
    1.23 ++			Format: <root_filesystem>[:root_directory]
    1.24 + 
    1.25 + 	rootdelay=	[KNL] Delay (in seconds) to pause before attempting to
    1.26 + 			mount the root filesystem
    1.27 +--- linux-3.2.40/init/do_mounts.c
    1.28 ++++ linux-3.2.40/init/do_mounts.c
    1.29 +@@ -28,6 +28,7 @@
    1.30 + int root_mountflags = MS_RDONLY | MS_SILENT;
    1.31 + static char * __initdata root_device_name;
    1.32 + static char __initdata saved_root_name[64];
    1.33 ++static char __initdata saved_root_directory[256];
    1.34 + static int root_wait;
    1.35 + 
    1.36 + dev_t ROOT_DEV;
    1.37 +@@ -255,7 +256,20 @@
    1.38 + 
    1.39 + static int __init root_dev_setup(char *line)
    1.40 + {
    1.41 ++	char *s;
    1.42 ++
    1.43 ++	strcpy(saved_root_directory, ".");
    1.44 + 	strlcpy(saved_root_name, line, sizeof(saved_root_name));
    1.45 ++	s = strchr(saved_root_name, ':');
    1.46 ++	if (s) {
    1.47 ++		*s = '\0';
    1.48 ++		s = strchr(line, ':') + 1;
    1.49 ++		while (*s == '/')
    1.50 ++			s++;
    1.51 ++		if (*s)
    1.52 ++			strlcpy(saved_root_directory, s,
    1.53 ++				sizeof(saved_root_directory));
    1.54 ++	}
    1.55 + 	return 1;
    1.56 + }
    1.57 + 
    1.58 +@@ -554,5 +568,5 @@
    1.59 + out:
    1.60 + 	devtmpfs_mount("dev");
    1.61 + 	sys_mount(".", "/", NULL, MS_MOVE, NULL);
    1.62 +-	sys_chroot((const char __user __force *)".");
    1.63 ++	sys_chroot((const char __user __force *)saved_root_directory);
    1.64 + }