[PATCH v3] fs: fat: Handle 'FAT sector size mismatch'

[Balaji Selvanathan]

Hi Tom,

On 1/29/2026 2:11 AM, Tom Rini wrote:
> On Thu, Jan 22, 2026 at 12:04:42PM +0530, Balaji Selvanathan wrote:
>
>> From: Varadarajan Narayanan <varadarajan.narayanan at oss.qualcomm.com>
>>
>> Do FAT read and write based on the device sector size
>> instead of the size recorded in the FAT meta data.
>>
>> FAT code issues i/o in terms of the sector size. Convert that to
>> device sector size before doing the actual i/o. Additionally,
>> handle leading/trailing blocks when the meta data based block
>> no and i/o size is not an exact multiple of the device sector
>> size or vice versa.
>>
>> Tested on UFS device with sector size 4096 and meta data recorded
>> sector size 512.
>>
>> Signed-off-by: Varadarajan Narayanan <varadarajan.narayanan at oss.qualcomm.com>
> First thing, clang shows a lot of warnings from this:
> https://source.denx.de/u-boot/u-boot/-/jobs/1365316
> Second thing, filesystem tests do pass:
> https://source.denx.de/u-boot/u-boot/-/jobs/1365314
> Please make sure v4 is put through CI:
> https://docs.u-boot.org/en/latest/develop/ci_testing.html

Sure, will address the warnings and will put v4 through CI.

Thanks,

Balaji

>
> Thanks!
>