ethtool: Clarify use of size field for ETHTOOL_GRXFHINDIR

In order to find out the device's RX flow hash table size, ethtool
initially uses ETHTOOL_GRXFHINDIR with a buffer size of zero.  This
must be supported, but it is not necessary to support any other user
buffer size less than the device table size.

Signed-off-by: Ben Hutchings <bhutchings@solarflare.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Ben Hutchings 2011-12-15 13:51:16 +00:00 committed by David S. Miller
parent 5d531aaa64
commit 14596f7006

View File

@ -543,8 +543,9 @@ struct compat_ethtool_rxnfc {
/**
* struct ethtool_rxfh_indir - command to get or set RX flow hash indirection
* @cmd: Specific command number - %ETHTOOL_GRXFHINDIR or %ETHTOOL_SRXFHINDIR
* @size: On entry, the array size of the user buffer. On return from
* %ETHTOOL_GRXFHINDIR, the array size of the hardware indirection table.
* @size: On entry, the array size of the user buffer, which may be zero
* for %ETHTOOL_GRXFHINDIR. On return from %ETHTOOL_GRXFHINDIR, the
* array size of the hardware indirection table.
* @ring_index: RX ring/queue index for each hash value
*/
struct ethtool_rxfh_indir {