ethtool: Expand documentation of ethtool_ops::{get,set}_rxfh()
Some corner-cases are not explained properly.
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
diff --git a/include/linux/ethtool.h b/include/linux/ethtool.h
index 212f537..886e127 100644
--- a/include/linux/ethtool.h
+++ b/include/linux/ethtool.h
@@ -162,15 +162,16 @@
* Will not be called if @get_rxfh_indir_size returns zero.
* @get_rxfh: Get the contents of the RX flow hash indirection table and hash
* key.
- * Will not be called if @get_rxfh_indir_size and @get_rxfh_key_size
- * returns zero.
+ * Will only be called if one or both of @get_rxfh_indir_size and
+ * @get_rxfh_key_size are implemented and return non-zero.
* Returns a negative error code or zero.
* @set_rxfh_indir: Set the contents of the RX flow hash indirection table.
* Will not be called if @get_rxfh_indir_size returns zero.
- * @set_rxfh: Set the contents of the RX flow hash indirection table and
- * hash key.
- * Will not be called if @get_rxfh_indir_size and @get_rxfh_key_size
- * returns zero.
+ * @set_rxfh: Set the contents of the RX flow hash indirection table and/or
+ * hash key. Either or both arguments may be %NULL if that attribute
+ * is not to be changed.
+ * Will only be called if one or both of @get_rxfh_indir_size and
+ * @get_rxfh_key_size are implemented and return non-zero.
* Returns a negative error code or zero.
* @get_channels: Get number of channels.
* @set_channels: Set number of channels. Returns a negative error code or
@@ -244,8 +245,8 @@
int (*reset)(struct net_device *, u32 *);
u32 (*get_rxfh_key_size)(struct net_device *);
u32 (*get_rxfh_indir_size)(struct net_device *);
- int (*get_rxfh)(struct net_device *, u32 *, u8 *);
- int (*set_rxfh)(struct net_device *, u32 *, u8 *);
+ int (*get_rxfh)(struct net_device *, u32 *indir, u8 *key);
+ int (*set_rxfh)(struct net_device *, u32 *indir, u8 *key);
int (*get_rxfh_indir)(struct net_device *, u32 *);
int (*set_rxfh_indir)(struct net_device *, const u32 *);
void (*get_channels)(struct net_device *, struct ethtool_channels *);