Large Block Devices not supported in 64 bit

Large Block Devices not supported in 64 bit

[Christian Schmid]

Hello.

I run kernel 2.6.17.11 vanilla in 64 bit mode with 32 bit emulation.

Unfortunately there is no support for file-systems bigger than 2 TB in 64 bit mode.

erikm in #kernelnewbies told me to report it here:

<Dragony> statfs("/MD2", 0xff8deca4)              = -1 EOVERFLOW (Value too large for defined data type)
<erikm> Dragony: prolly no LBD support
<erikm> Dragony: ah wait, you probably do have support for large block devices, but the 32 bit 
portability syscall forgot to support it
<erikm> Dragony: see block/Kconfig
<Dragony> #XXX - it makes sense to enable this only for 32-bit subarch's, not for x86_64
<Dragony> #for instance.
<Dragony> config LBD
<Dragony>         bool "Support for Large Block Devices"
<Dragony>         depends on X86 || (MIPS && 32BIT) || PPC32 || (S390 && !64BIT) || SUPERH || UML
<Dragony> yes but this option only appears in 32 bit mode not in 64 bit mode
<erikm> Dragony: hence my comment
<Dragony> actually /MD2 is mounted and i can access the files, but not any stats
<erikm> Dragony: it *IS* supported, but not properly backported to the 32 bit compatibility layer
<Dragony> hmm what can i do?
<erikm> Dragony: post to lkml

Can someone help me?

Regards,
Chris

Re: Large Block Devices not supported in 64 bit

[Chris Boot]

On 6 Sep 2006, at 16:12, Christian Schmid wrote:

> Hello.
>
> I run kernel 2.6.17.11 vanilla in 64 bit mode with 32 bit emulation.
>
> Unfortunately there is no support for file-systems bigger than 2 TB  
> in 64 bit mode.

There is. There just isn't any support for having the feature turned  
off. After all, the code needed on 32-bit systems to have large files  
(64-bit file offsets) isn't necessary on 64-bit systems: file offsets  
are already 64-bit by nature.

HTH,
Chris

-- 
Chris Boot
bootc@bootc.net
http://www.bootc.net/