Re: [PATCH 17/18] common: partitions: efi: record type UUID in cdev

[Ahmad Fatoum <a.fatoum@pengutronix.de>]

On 31.05.23 21:31, Marco Felsch wrote:
> Hi Ahmad,
> 
> On 23-05-31, Ahmad Fatoum wrote:
>> We already record DOS partition type in cdev, so let's do the same for
>> GPT Type UUID. This will be used in a later commit to identify
>> barebox-state partitions.
>>
>> Signed-off-by: Ahmad Fatoum <a.fatoum@pengutronix.de>
>> ---
>>  common/partitions.c        | 2 +-
>>  common/partitions/efi.c    | 1 +
>>  common/partitions/parser.h | 5 ++++-
>>  fs/fs.c                    | 2 ++
>>  include/driver.h           | 6 +++++-
>>  5 files changed, 13 insertions(+), 3 deletions(-)
>>
>> diff --git a/common/partitions.c b/common/partitions.c
>> index b579559672a0..e3e8a9f3044d 100644
>> --- a/common/partitions.c
>> +++ b/common/partitions.c
>> @@ -50,7 +50,7 @@ static int register_one_partition(struct block_device *blk,
>>  
>>  	cdev->flags |= DEVFS_PARTITION_FROM_TABLE;
>>  
>> -	cdev->dos_partition_type = part->dos_partition_type;
>> +	cdev->typeuuid = part->typeuuid;
> 
> Even though it's an union I would prefer to make it easier for the
> reader (without checking the header and noticing that it is an union).
> So the above code would be:
> 
> 	if (blkdev_is_gpt_partitioned(blk))
> 		cdev->typeuuid = part->typeuuid;
> 	else if (blkdev_is_mbr_partitioned(blk))
> 		cdev->dos_partition_type = part->dos_partition_type;

I don't think this is implementable without a runtime cost. I'd leave
it as is.

> 
> with 
> 
> static inline blkdev_is_gpt_partitioned(struct block_device *blkdev)
> {
> 	return cdev_is_gpt_partitioned(&blkdev->cdev);
> }
> 
> Regards,
>   Marco
> 
>>  	strcpy(cdev->partuuid, part->partuuid);
>>  
>>  	free(partition_name);
>> diff --git a/common/partitions/efi.c b/common/partitions/efi.c
>> index df63b82afe24..2756337ab284 100644
>> --- a/common/partitions/efi.c
>> +++ b/common/partitions/efi.c
>> @@ -471,6 +471,7 @@ static void efi_partition(void *buf, struct block_device *blk,
>>  		pentry->size++;
>>  		part_set_efi_name(&ptes[i], pentry->name);
>>  		snprintf(pentry->partuuid, sizeof(pentry->partuuid), "%pUl", &ptes[i].unique_partition_guid);
>> +		pentry->typeuuid = ptes[i].partition_type_guid;
>>  		pd->used_entries++;
>>  	}
>>  }
>> diff --git a/common/partitions/parser.h b/common/partitions/parser.h
>> index f2f692f7903b..9cc41a7573fe 100644
>> --- a/common/partitions/parser.h
>> +++ b/common/partitions/parser.h
>> @@ -17,10 +17,13 @@
>>  
>>  struct partition {
>>  	char name[MAX_PARTITION_NAME];
>> -	u8 dos_partition_type;
>>  	char partuuid[MAX_UUID_STR];
>>  	uint64_t first_sec;
>>  	uint64_t size;
>> +	union {
>> +		u8 dos_partition_type;
>> +		guid_t typeuuid;
>> +	};
>>  };
>>  
>>  struct partition_desc {
>> diff --git a/fs/fs.c b/fs/fs.c
>> index 9a92e6e251e5..16cc072adfaf 100644
>> --- a/fs/fs.c
>> +++ b/fs/fs.c
>> @@ -110,6 +110,8 @@ void cdev_print(const struct cdev *cdev)
>>  		nbytes += printf("Filetype: %s\t", file_type_to_string(cdev->filetype));
>>  	if (cdev_is_mbr_partitioned(cdev->master))
>>  		nbytes += printf("DOS parttype: 0x%02x\t", cdev->dos_partition_type);
>> +	else if (cdev_is_gpt_partitioned(cdev->master))
>> +		nbytes += printf("GPT typeuuid: %pUl\t", &cdev->typeuuid);
>>  	if (*cdev->partuuid || *cdev->diskuuid)
>>  		nbytes += printf("%sUUID: %s", cdev_is_partition(cdev) ? "PART" : "DISK",
>>  				 cdev_is_partition(cdev) ? cdev->partuuid : cdev->diskuuid);
>> diff --git a/include/driver.h b/include/driver.h
>> index 5f2eae65466f..6407f7d6ba36 100644
>> --- a/include/driver.h
>> +++ b/include/driver.h
>> @@ -8,6 +8,7 @@
>>  
>>  #include <linux/list.h>
>>  #include <linux/ioport.h>
>> +#include <linux/uuid.h>
>>  #include <of.h>
>>  #include <filetype.h>
>>  
>> @@ -536,12 +537,15 @@ struct cdev {
>>  	unsigned int flags;
>>  	int open;
>>  	struct mtd_info *mtd;
>> -	u8 dos_partition_type;
>>  	struct cdev *link;
>>  	struct list_head link_entry, links;
>>  	struct list_head partition_entry, partitions;
>>  	struct cdev *master;
>>  	enum filetype filetype;
>> +	union {
>> +		u8 dos_partition_type;
>> +		guid_t typeuuid;
>> +	};
>>  };
>>  
>>  int devfs_create(struct cdev *);
>> -- 
>> 2.39.2
>>
>>
>>
> 

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