[PATCH V4] reduce bmv_count in xfs_vn_fiemap

[Olaf Weber]

Eric Sandeen writes:

> commit 6321e3ed2acf3ee9643cdd403e1c88605d7944ba caused
> the full bmv_count's worth of getbmapx structures to get
> allocated; telling it to do MAXEXTNUM was a bit insane,
> resulting in ENOMEM every time.

> Chop it down to something reasonable, the number of slots
> in the caller's input buffer.  If this is too large the 
> caller may get ENOMEM but the reason should not be a
> mystery, and they can try again with something smaller.

> We add 1 to the value because in the normal getbmap
> world, bmv_count includes the header and xfs_getbmap does:

>         nex = bmv->bmv_count - 1;
>         if (nex <= 0)
>                 return XFS_ERROR(EINVAL);

> Signed-off-by: Eric Sandeen <sandeen at sandeen.net>

Reviewed-By: Olaf Weber <olaf at sgi.com>


Thanks,

Olaf

-- 
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