[U-Boot] Porting UBI fixes (specially fastmap's) to U-Boot

[Richard Weinberger <richard@nod.at>]

Hi!

Am 08.10.2015 um 14:51 schrieb Heiko Schocher:
> Hello Ezequiel, Richard,
> 
> Am 02.10.2015 um 18:27 schrieb Ezequiel Garcia:
>> Hello Heiko,
>>
>> According to Richard Weinberger, UBI fastmap is broken in U-Boot.
>> There are plenty
>> of fixes in Linux that we should pull in U-Boot to fix it.
>>
>> Maybe you are already aware of this and you have some work-in-progress
>> patches to share?
>> Otherwise, I might be able to spend some time working on this in the next weeks.
> 
> I just tried to do this port ... but stumbled over some issues, I just try to
> looking at ... but running out of time for doing more ...
> 
> - ubifastmap needs now scatterlist ... we have no support for this
>   currently in U-Boot.

Huh?

We have support for that in UBI. But the only user is UBI block.

> - I get some bogus compilerwarnings:
> 
>   CC      drivers/mtd/ubi/fastmap-wl.o
> drivers/mtd/ubi/fastmap-wl.c:69:3: warning: implicit declaration of function 'wl_tree_add' [-Wimplicit-function-declaration]
> 
> wl_tree_add is declared static here:
> http://lxr.free-electrons.com/source/drivers/mtd/ubi/wl.c#L152
> 
> but called from fastmap-wl.c
> http://lxr.free-electrons.com/source/drivers/mtd/ubi/fastmap-wl.c#L64

wl.c has a "#include "fastmap-wl.c".

> same for:
> find_mean_wl_entry
> self_check_in_wl_tree
> wl_get_wle
> find_wl_entry
> prot_queue_add
> schedule_ubi_work
> schedule_erase
> 
> drivers/mtd/ubi/fastmap-wl.c: In function 'ubi_is_erase_work':
> drivers/mtd/ubi/fastmap-wl.c:340:1: warning: control reaches end of non-void function [-Wreturn-type]
> 
> :-(

???

/**
 * ubi_is_erase_work - checks whether a work is erase work.
 * @wrk: The work object to be checked
 */
int ubi_is_erase_work(struct ubi_work *wrk)
{
        return wrk->func == erase_worker;
}


> Does this warnings not occur when compiling linux with fastmap support?

Nope. But I'm not using fancy new compilers/flags.

> I used as base for porting ubi/ubifs from linux:
> 
>    commit 64291f7db5bd8150a74ad2036f1037e6a0428df2
>     Author: Linus Torvalds <torvalds@linux-foundation.org>
>     Date:   Sun Aug 30 11:34:09 2015 -0700
> 
>         Linux 4.2

Just checked v4.2

> 
> @Richard: a first change for U-Boot wish:
> 
> You used here and there sometimes "free" as an variable name ... for example:
> in "drivers/mtd/ubi/fastmap.c"
> 
> static int scan_pool(struct ubi_device *ubi, struct ubi_attach_info *ai,
>                      int *pebs, int pool_size, unsigned long long *max_sqnum,
>                      struct list_head *free)
> 
> compiling this under U-Boot drops:
> 
>   CC      drivers/mtd/ubi/fastmap.o
> drivers/mtd/ubi/fastmap.c: In function 'scan_pool':
> drivers/mtd/ubi/fastmap.c:475:3: error: called object 'free' is not a function

Which gcc warning-flag triggers that?

> (line number differs from mainline, because I added some U-Boot specific
>  line above)
> 
> Could we rename this var to something else ... like for example "pfree" ?
> I can prepare a patch for linux, if this would be Ok for you.

Unless I'm mistaken this is fine in C.
So, what exactly is the problem here?

Thanks,
//richard