Hi Lukas,
How do you think about my comment?

Regards,
Kazuya Mio

2011/05/13 17:55, Kazuya Mio wrote:

2011/05/13 15:36, Lukas Czerner wrote:

quoted

That is because due to defensive programming we planted a lot of
BUG_ON's to prevent the length of the gap cache to be zero, but in this
case it actually will be zero, because there will be no gap at the end
of the file.

Um, I think there is a block (blocksize -1 byte) in gap.
And this gap should be used for the next block searching.
According to ext4_ext_in_cache(), len=0 means the special case
which we have no cache extent, so len=0 should be disallowed.

Moreover, if we create the file which has 2^32-1 offset,
we can't get extent which starts from this offset with FIEMAP ioctl.
That's why I think the maximum file size should be 2^32-1 * blocksize.

Regards,
Kazuya Mio