From mboxrd@z Thu Jan  1 00:00:00 1970
From: Lukasz Majewski <l.majewski@samsung.com>
Date: Fri, 05 Oct 2012 12:50:37 +0200
Subject: [U-Boot] [PATCH v3 5/7] gpt: Support for GPT (GUID Partition
 Table) restoration
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Hi Stephen,

> On 09/13/2012 02:10 AM, Lukasz Majewski wrote:
> > The restoration of GPT table (both primary and secondary) is now
> > possible. Simple GUID generation is supported.
> 
> > diff --git a/include/part.h b/include/part.h
> 
> > +int set_gpt_table(block_dev_desc_t *dev_desc,
> > +		  gpt_header *gpt_h, gpt_entry *gpt_e);
> 
> The API here isn't very generic; it requires the caller to have
> formatted the GPT entirely by itself, which means having complete
> knowledge of how to lay out a GPT header and partition table entry.
> Right now, all that knowledge is contained inside the implementation
> of the "gpt" command - what if some other unrelated code wanted to
> write a GPT; it'd have to duplicate everything.

I must admit, that you are correct here.

> 
> I was thinking of a much more generic interface, where each partition
> is described using abstract structs, and the creation of the actual
> on-disk layout is handling inside the set_gpt_table() function. That
> would presumably allow the same abstract structs to be passed to e.g.
> set_mbr_partition_table() and a generic "ptable create" command to be
> created.

If I understood you correctly, you propose to devise an abstraction
layer to store information about each partition - e.g.

struct partition {
	char *name,
	size_t size,
	size_t start,
	...
}

then 

struct disk {
	struct partition p1,
	struct partition p2,
	...
}

And then pass this struct disk to set_gpt_table() function.

This would "clean" the partition related code and be a good starting
point for further abstracting (if needed).


-- 
Best regards,

Lukasz Majewski

Samsung Poland R&D Center | Linux Platform Group