Some filesystems have a UUID stored in its superblock. To allow using root=UUID=... for the kernel command line we need a way to read-out the filesystem UUID. This is what this patch tries to do.
Keep in mind that this patch is an RFC and I hope to get some feedback on this patch. This is what blkid under linux gives me: /dev/sdh1: LABEL="data" UUID="b6995cec-97e2-48b8-94dc-8ba7afc92bac" TYPE="ext4" PARTUUID="43f21f0e-01" /dev/sdh2: LABEL="rfs" UUID="8d020de7-c75e-4674-948e-f7838a931b02" TYPE="ext4" PARTUUID="43f21f0e-02" And here is the output from u-boot: => sata init AHCI 0001.0300 32 slots 1 ports 3 Gbps 0x1 impl SATA mode flags: ncq stag pm led clo only pmp pio slum part SATA Device Info: S/N: 000060059798A1000014 Product model number: SFCA4096H1BR4TO-I-MS-236-STD Firmware version: 20111021 Capacity: 7793856 sectors => fs_uuid sata 0:1 ; print fs_uuid; fs_uuid sata 0:2 ; print fs_uuid fs_uuid=b6995cec-97e2-48b8-94dc-8ba7afc92bac fs_uuid=8d020de7-c75e-4674-948e-f7838a931b02 Signed-off-by: Christian Gmeiner <christian.gmei...@gmail.com> --- common/Makefile | 1 + common/cmd_fs_uuid.c | 23 +++++++++++++++++++++++ fs/ext4/ext4_common.c | 9 +++++++++ fs/fs.c | 28 ++++++++++++++++++++++++++++ include/ext4fs.h | 1 + include/fs.h | 2 ++ 6 files changed, 64 insertions(+) create mode 100644 common/cmd_fs_uuid.c diff --git a/common/Makefile b/common/Makefile index b19d379..d5d3315 100644 --- a/common/Makefile +++ b/common/Makefile @@ -188,6 +188,7 @@ obj-y += usb.o usb_hub.o obj-$(CONFIG_USB_STORAGE) += usb_storage.o endif obj-$(CONFIG_CMD_FASTBOOT) += cmd_fastboot.o +obj-$(CONFIG_CMD_FS_UUID) += cmd_fs_uuid.o obj-$(CONFIG_CMD_USB_MASS_STORAGE) += cmd_usb_mass_storage.o obj-$(CONFIG_CMD_THOR_DOWNLOAD) += cmd_thordown.o diff --git a/common/cmd_fs_uuid.c b/common/cmd_fs_uuid.c new file mode 100644 index 0000000..3af9518 --- /dev/null +++ b/common/cmd_fs_uuid.c @@ -0,0 +1,23 @@ +/* + * cmd_fs_uuid.c -- fs_uuid command + * + * Copyright (C) 2014, Bachmann electronic GmbH + * + * SPDX-License-Identifier: GPL-2.0+ + */ + +#include <common.h> +#include <command.h> +#include <fs.h> + +static int do_fs_uuid_wrapper(cmd_tbl_t *cmdtp, int flag, int argc, char * const argv[]) +{ + return do_fs_uuid(cmdtp, flag, argc, argv, FS_TYPE_ANY); +} + +U_BOOT_CMD( + fs_uuid, 3, 0, do_fs_uuid_wrapper, + "filesystem UUDI related commands", + "<interface> <dev>:<part>\n" + " - print filesystem UUID\n" +); diff --git a/fs/ext4/ext4_common.c b/fs/ext4/ext4_common.c index 33d69c9..926b6c6 100644 --- a/fs/ext4/ext4_common.c +++ b/fs/ext4/ext4_common.c @@ -2246,3 +2246,12 @@ fail: return 0; } + +void ext4fs_uuid(char *uuid_str) +{ + if (ext4fs_root == NULL) + return; + + uuid_bin_to_str((unsigned char *)ext4fs_root->sblock.unique_id, uuid_str, + UUID_STR_FORMAT_STD); +} diff --git a/fs/fs.c b/fs/fs.c index dd680f3..f8c6d64 100644 --- a/fs/fs.c +++ b/fs/fs.c @@ -85,6 +85,7 @@ struct fstype_info { int (*size)(const char *filename); int (*read)(const char *filename, void *buf, int offset, int len); int (*write)(const char *filename, void *buf, int offset, int len); + void (*uuid)(char *uuid_str); void (*close)(void); }; @@ -113,6 +114,7 @@ static struct fstype_info fstypes[] = { .size = ext4fs_size, .read = ext4_read_file, .write = fs_write_unsupported, + .uuid = ext4fs_uuid, }, #endif #ifdef CONFIG_SANDBOX @@ -206,6 +208,14 @@ static void fs_close(void) fs_type = FS_TYPE_ANY; } +void fs_uuid(char *uuid_str) +{ + struct fstype_info *info = fs_get_info(fs_type); + + if (info->uuid) + info->uuid(uuid_str); +} + int fs_ls(const char *dirname) { int ret; @@ -289,6 +299,24 @@ int fs_write(const char *filename, ulong addr, int offset, int len) return ret; } +int do_fs_uuid(cmd_tbl_t *cmdtp, int flag, int argc, char * const argv[], + int fstype) +{ + char uuid[37]; + memset(uuid, 0, sizeof(uuid)); + + if (argc != 3) + return CMD_RET_USAGE; + + if (fs_set_blk_dev(argv[1], argv[2], fstype)) + return 1; + + fs_uuid(uuid); + setenv("fs_uuid", uuid); + + return 0; +} + int do_size(cmd_tbl_t *cmdtp, int flag, int argc, char * const argv[], int fstype) { diff --git a/include/ext4fs.h b/include/ext4fs.h index 6c419f3..4011370 100644 --- a/include/ext4fs.h +++ b/include/ext4fs.h @@ -132,6 +132,7 @@ struct ext_filesystem *get_fs(void); int ext4fs_open(const char *filename); int ext4fs_read(char *buf, unsigned len); int ext4fs_mount(unsigned part_length); +void ext4fs_uuid(char *uuid_str); void ext4fs_close(void); void ext4fs_reinit_global(void); int ext4fs_ls(const char *dirname); diff --git a/include/fs.h b/include/fs.h index 06a45f2..1956b67 100644 --- a/include/fs.h +++ b/include/fs.h @@ -82,6 +82,8 @@ int fs_write(const char *filename, ulong addr, int offset, int len); * Common implementation for various filesystem commands, optionally limited * to a specific filesystem type via the fstype parameter. */ +int do_fs_uuid(cmd_tbl_t *cmdtp, int flag, int argc, char * const argv[], + int fstype); int do_size(cmd_tbl_t *cmdtp, int flag, int argc, char * const argv[], int fstype); int do_load(cmd_tbl_t *cmdtp, int flag, int argc, char * const argv[], -- 1.9.3 _______________________________________________ U-Boot mailing list U-Boot@lists.denx.de http://lists.denx.de/mailman/listinfo/u-boot