[U-Boot] [PATCH] efi_loader: disk: Fix CONFIG_BLK breakage

[Simon Glass]

Hi Alex,

On 10 August 2016 at 07:02, Alexander Graf <agraf at suse.de> wrote:
> On 08/10/2016 02:56 PM, Simon Glass wrote:
>>
>> +Tom
>>
>> Hi Alex,
>>
>> On 10 August 2016 at 01:47, Alexander Graf <agraf at suse.de> wrote:
>>>>
>>>> On 08 Aug 2016, at 23:44, Simon Glass <sjg at chromium.org> wrote:
>>>>
>>>> Hi Alexander,
>>>>
>>>> On 5 August 2016 at 06:49, Alexander Graf <agraf at suse.de> wrote:
>>>>>
>>>>> When using CONFIG_BLK, there were 2 issues:
>>>>>
>>>>>   1) The name we generate the device with has to match the
>>>>>      name we set in efi_set_bootdev()
>>>>>
>>>>>   2) The device we pass into our block functions was wrong,
>>>>>      we should not rediscover it but just use the already known
>>>>>      pointer.
>>>>>
>>>>> This patch fixes both issues.
>>>>>
>>>>> Signed-off-by: Alexander Graf <agraf at suse.de>
>>>>> ---
>>>>> cmd/bootefi.c             | 23 ++++++++++++++++++-----
>>>>> lib/efi_loader/efi_disk.c | 18 +++++++++++-------
>>>>> 2 files changed, 29 insertions(+), 12 deletions(-)
>>>>>
>> [...]
>>
>>>>> diff --git a/lib/efi_loader/efi_disk.c b/lib/efi_loader/efi_disk.c
>>>>> index c434c92..e00a747 100644
>>>>> --- a/lib/efi_loader/efi_disk.c
>>>>> +++ b/lib/efi_loader/efi_disk.c
>>>>> @@ -31,6 +31,8 @@ struct efi_disk_obj {
>>>>>         struct efi_device_path_file_path *dp;
>>>>>         /* Offset into disk for simple partitions */
>>>>>         lbaint_t offset;
>>>>> +       /* Internal block device */
>>>>> +       const struct blk_desc *desc;
>>>>
>>>> Rather than storing this, can you store the udevice?
>>>
>>> I could, but then I would diverge between the CONFIG_BLK and
>>> non-CONFIG_BLK path again, which would turn the code into an #ifdef mess
>>> (read: hard to maintain), because the whole device creation path relies on
>>> struct blk_desc * today and doesn’t pass the udevice anywhere.
>>>
>>> Do you feel strongly about this? To give you an idea how messy it gets,
>>> the diff is below.
>>
>> Actually I'd like to make this feature depend on CONFIG_BLK. If we add
>> new features that don't use driver model, and then use the legacy data
>> structures such that converting to driver model becomes harder, we'll
>> never be done.
>>
>> I did mention this at the beginning and it seems to have come to pass.
>>
>> In order of preference from my side:
>>
>> 1. Make EFI_LOADER depend on BLK
>
>
> If we make EFI_LOADER depend on BLK, doesn't that break all systems that
> need storage that isn't converted to device model today? Like the SATA
> breakage on Xilinx systems, just at a much bigger scale?

No it just means that these platforms need to move to BLK before they
can use the EFI loader. Given the embryonic nature of this feature,
that seems reasonable, and the impact would be small. It will also
encourage conversion and keep the code cleaner.

Regards,
Simon