Re: [PATCH v3 2/4] block: partitions: populate fwnode

[Jens Axboe <axboe@kernel.dk>]

On 6/26/24 1:58 PM, Daniel Golle wrote:
> On Wed, Jun 26, 2024 at 01:43:49PM -0600, Jens Axboe wrote:
>> On 6/25/24 8:50 PM, Daniel Golle wrote:
>>> diff --git a/block/partitions/core.c b/block/partitions/core.c
>>> index ab76e64f0f6c..f88829e254e6 100644
>>> --- a/block/partitions/core.c
>>> +++ b/block/partitions/core.c
>>> @@ -10,6 +10,8 @@
>>>  #include <linux/ctype.h>
>>>  #include <linux/vmalloc.h>
>>>  #include <linux/raid/detect.h>
>>> +#include <linux/property.h>
>>> +
>>>  #include "check.h"
>>>  
>>>  static int (*const check_part[])(struct parsed_partitions *) = {
>>> @@ -281,6 +283,42 @@ static ssize_t whole_disk_show(struct device *dev,
>>>  }
>>>  static const DEVICE_ATTR(whole_disk, 0444, whole_disk_show, NULL);
>>>  
>>> +static struct fwnode_handle *find_partition_fwnode(struct block_device *bdev)
>>> +{
>>> +	struct fwnode_handle *fw_parts, *fw_part;
>>> +	struct device *ddev = disk_to_dev(bdev->bd_disk);
>>> +	const char *partname, *uuid;
>>> +	u32 partno;
>>> +
>>> +	fw_parts = device_get_named_child_node(ddev, "partitions");
>>> +	if (!fw_parts)
>>> +		fw_parts = device_get_named_child_node(ddev->parent, "partitions");
>>> +
>>> +	if (!fw_parts)
>>> +		return NULL;
>>
>> That last if check should to inside the previous one.
> 
> Actually the previous one should have been removed entirely. I somehow
> forgot to 'git add' that change.
> 
>>
>>> +	fwnode_for_each_child_node(fw_parts, fw_part) {
>>> +		if (!fwnode_property_read_string(fw_part, "uuid", &uuid) &&
>>> +		    (!bdev->bd_meta_info || strlen(uuid) > PARTITION_META_INFO_UUIDLTH ||
>>> +		     strncmp(uuid, bdev->bd_meta_info->uuid, PARTITION_META_INFO_UUIDLTH)))
>>> +			continue;
>>> +
>>> +		if (!fwnode_property_read_string(fw_part, "partname", &partname) &&
>>> +		    (!bdev->bd_meta_info || strlen(uuid) > PARTITION_META_INFO_VOLNAMELTH ||
>>> +		     strncmp(partname, bdev->bd_meta_info->volname,
>>> +			     PARTITION_META_INFO_VOLNAMELTH)))
>>> +			continue;
>>
>> This is pretty hard to make sense of...
> 
> I'll add comments explaining it. Or should I use another syntax, e.g. several
> nested if-clauses, instead?

Maybe some kind of helpers for these instead, with comments? Nobody can
read the above.

-- 
Jens Axboe