[U-Boot] [PATCH] fs: make it possible to read the filesystem UUID
Christian Gmeiner
christian.gmeiner at gmail.com
Mon Nov 3 11:47:25 CET 2014
Hi Simon,
2014-11-01 16:13 GMT+01:00 Simon Glass <sjg at chromium.org>:
> Hi Christian,
>
> On 31 October 2014 09:08, Christian Gmeiner <christian.gmeiner at gmail.com> wrote:
>> 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.
>>
>> Hit any key to stop autoboot: 0
>> => fsuuid
>> fsuuid - Look up a filesystem UUID
>>
>> Usage:
>> fsuuid <interface> <dev>:<part>
>> - print filesystem UUID
>> fsuuid <interface> <dev>:<part> <varname>
>> - set environment variable to filesystem UUID
>>
>> => fsuuid mmc 0:1
>> d9f9fc05-45ae-4a36-a616-fccce0e4f887
>> => fsuuid mmc 0:2
>> eb3db83c-7b28-499f-95ce-9e0bb21cda81
>> => fsuuid mmc 0:1 uuid1
>> => fsuuid mmc 0:2 uuid2
>> => printenv uuid1
>> uuid1=d9f9fc05-45ae-4a36-a616-fccce0e4f887
>> => printenv uuid2
>> uuid2=eb3db83c-7b28-499f-95ce-9e0bb21cda81
>> =>
>>
>> Signed-off-by: Christian Gmeiner <christian.gmeiner at gmail.com>
>
> If this is version 2 you should have a change list. You can use patman
> (tools/patman/patman) to automate this.
Yes.. the first version was the RFC. I really need to look into
patman. Normally I do
these things per hand.
>
>> ---
>> README | 1 +
>> common/Makefile | 1 +
>> fs/ext4/ext4fs.c | 15 +++++++++++++++
>> fs/fs.c | 39 +++++++++++++++++++++++++++++++++++++++
>> include/ext4fs.h | 1 +
>> include/fs.h | 2 ++
>> 6 files changed, 59 insertions(+)
>>
>> diff --git a/README b/README
>> index 7b5538e..53b84a6 100644
>> --- a/README
>> +++ b/README
>> @@ -989,6 +989,7 @@ The following options need to be configured:
>> CONFIG_CMD_EXT4 * ext4 command support
>> CONFIG_CMD_FS_GENERIC * filesystem commands (e.g. load, ls)
>> that work for multiple fs types
>> + CONFIG_CMD_FS_UUID * Look up a filesystem UUID
>> CONFIG_CMD_SAVEENV saveenv
>> CONFIG_CMD_FDC * Floppy Disk Support
>> CONFIG_CMD_FAT * FAT command support
>> diff --git a/common/Makefile b/common/Makefile
>> index 6cc4de8..508a0b2 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/fs/ext4/ext4fs.c b/fs/ext4/ext4fs.c
>> index cbdc220..61b6dc2 100644
>> --- a/fs/ext4/ext4fs.c
>> +++ b/fs/ext4/ext4fs.c
>> @@ -187,6 +187,21 @@ int ext4fs_size(const char *filename)
>> return ext4fs_open(filename);
>> }
>>
>> +int ext4fs_uuid(char *uuid_str)
>> +{
>> + if (ext4fs_root == NULL)
>> + return -1;
>> +
>> +#ifdef CONFIG_LIB_UUID
>> + uuid_bin_to_str((unsigned char *)ext4fs_root->sblock.unique_id,
>> + uuid_str, UUID_STR_FORMAT_STD);
>> +
>> + return 0;
>> +#endif
>> +
>> + return -ENOSYS;
>> +}
>> +
>> int ext4fs_read(char *buf, unsigned len)
>> {
>> if (ext4fs_root == NULL || ext4fs_file == NULL)
>> diff --git a/fs/fs.c b/fs/fs.c
>> index dd680f3..492d8b1 100644
>> --- a/fs/fs.c
>> +++ b/fs/fs.c
>> @@ -15,6 +15,7 @@
>> */
>>
>> #include <config.h>
>> +#include <errno.h>
>> #include <common.h>
>> #include <part.h>
>> #include <ext4fs.h>
>> @@ -86,6 +87,7 @@ struct fstype_info {
>> int (*read)(const char *filename, void *buf, int offset, int len);
>> int (*write)(const char *filename, void *buf, int offset, int len);
>> void (*close)(void);
>> + int (*uuid)(char *uuid_str);
>> };
>>
>> static struct fstype_info fstypes[] = {
>> @@ -113,6 +115,7 @@ 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 +209,17 @@ static void fs_close(void)
>> fs_type = FS_TYPE_ANY;
>> }
>>
>> +int fs_uuid(char *uuid_str)
>> +{
>> + struct fstype_info *info = fs_get_info(fs_type);
>> + int ret = -ENOSYS;
>> +
>> + if (info->uuid)
>> + ret = info->uuid(uuid_str);
>> +
>> + return ret;
>> +}
>> +
>> int fs_ls(const char *dirname)
>> {
>> int ret;
>> @@ -443,3 +457,28 @@ int do_save(cmd_tbl_t *cmdtp, int flag, int argc, char * const argv[],
>>
>> return 0;
>> }
>> +
>> +int do_fs_uuid(cmd_tbl_t *cmdtp, int flag, int argc, char * const argv[],
>> + int fstype)
>> +{
>> + int ret;
>> + char uuid[37];
>> + memset(uuid, 0, sizeof(uuid));
>> +
>> + if (argc < 3 || argc > 4)
>> + return CMD_RET_USAGE;
>> +
>> + if (fs_set_blk_dev(argv[1], argv[2], fstype))
>> + return 1;
>> +
>> + ret = fs_uuid(uuid);
>> + if (ret)
>> + return ret;
>
> Here you should return CMD_RET_SUCCESS or CMD_RET_FAILURE. You should
> not return raw errors since they are not the same thing.
Okay. will be fixed in next version of the patch.
>
>> +
>> + if (argc == 4)
>> + setenv(argv[3], uuid);
>> + else
>> + printf("%s\n", uuid);
>> +
>> + return 0;
>> +}
>> diff --git a/include/ext4fs.h b/include/ext4fs.h
>> index 6c419f3..19816de 100644
>> --- a/include/ext4fs.h
>> +++ b/include/ext4fs.h
>> @@ -137,6 +137,7 @@ void ext4fs_reinit_global(void);
>> int ext4fs_ls(const char *dirname);
>> int ext4fs_exists(const char *filename);
>> int ext4fs_size(const char *filename);
>> +int ext4fs_uuid(char *uuid_str);
>> void ext4fs_free_node(struct ext2fs_node *node, struct ext2fs_node *currroot);
>> int ext4fs_devread(lbaint_t sector, int byte_offset, int byte_len, char *buf);
>> void ext4fs_set_blk_dev(block_dev_desc_t *rbdd, disk_partition_t *info);
>> diff --git a/include/fs.h b/include/fs.h
>> index 06a45f2..41082b3 100644
>> --- a/include/fs.h
>> +++ b/include/fs.h
>> @@ -92,5 +92,7 @@ int file_exists(const char *dev_type, const char *dev_part, const char *file,
>> int fstype);
>> int do_save(cmd_tbl_t *cmdtp, int flag, int argc, char * const argv[],
>> int fstype);
>> +int do_fs_uuid(cmd_tbl_t *cmdtp, int flag, int argc, char * const argv[],
>> + int fstype);
>
> Can you please add a function comment for this?
Yes I will add one - directly here in the .h file?
>
>>
>> #endif /* _FS_H */
>> --
>> 1.9.3
>>
>
> Regards,
> Simon
Greets
--
Christian Gmeiner, MSc
https://soundcloud.com/christian-gmeiner
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