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SubjectRe: blocks or KB? (was: .. current meaning of blk_size array)
On Nov 15, 2001  00:34 -0500, William Park wrote:
> Judging by 'driver/block/nbd.c', it counts by BLOCK_SIZE=1204
> (BLOCK_SIZE_BITS=10), even though you can set the block size to
> [512,1024,...,PAGE_SIZE=4096]. Since NBD counts this 1KB block using
> 'u64' integer, the ultimate size of filesystem is determined by the
> kernel block device support.
> Looking at 'fs/block_dev.c', you can set the block size to
> [512,1024,...,PAGE_SIZE=4096] also. But, 'max_block()' returns block
> count in whatever block size of the device, not in BLOCK_SIZE:

Sadly, while you _might_ be able to change the BLOCK_SIZE to be something
other than 1kB, there are probably so many places that assume a 1kB size
that you will need a lot of fixing. I'm not saying that fixing these
things is bad (it would actually be good for many reasons), but just a
heads-up that changing the BLOCK_SIZE define _probably_ won't get you 8TB
devices (maybe a broken system, or corrupt fs instead). Use caution.

Cheers, Andreas
Andreas Dilger

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