Re: [Madwifi-devel] [RFC] Add WE retry support

[bruno r. <br...@th...>]

On Saturday 01 March 2008 10:49:18 Luis R. Rodriguez wrote:
> The following patch adds retry support. It applies ontop of trunk,
> now r3366. This enables modifying retry limits on madwifi via Wext. While
> the Wireless-extensions implementation on the ioctl adds support for
> short retry, long retry and even retry lifetime the HAL only allows us
> currently to modify one simple retry limit.

couldn't we set either the short or the long retry value in ath_tx_start() 
depending on the size of the packet to support short and long retries?

bruno

> You can also wget this from:
>
> http://winlab.rutgers.edu/~mcgrof/patches/2008-02-29/patch-02-retry-fix.dif
>f
>
> Signed-Off by: Luis Rodriguez <mc...@wi...>
>
> diff -Naurp madwifi-3366.orig/ath/if_ath.c madwifi-3366/ath/if_ath.c
> --- madwifi-3366.orig/ath/if_ath.c	2008-02-23 09:13:09.000000000 -0500
> +++ madwifi-3366/ath/if_ath.c	2008-02-29 19:52:23.000000000 -0500
> @@ -7635,6 +7635,12 @@ ath_tx_start(struct net_device *dev, str
>  			sc->sc_rc->ops->findrate(sc, an, shortPreamble, skb->len,
>  				&rix, &try0, &txrate);
>
> +			/* Note: HAL does not support distinguishing between short
> +			* and long retry. These both are set via try0 here then.
> +			* We can fix this in ath5k though */
> +			if (vap->iv_flags & IEEE80211_F_SWRETRY && vap->iv_txmax != try0)
> +				try0 = vap->iv_txmax;
> +
>  			/* Ratecontrol sometimes returns invalid rate index */
>  			if (rix != 0xff)
>  				an->an_prevdatarix = rix;
> diff -Naurp madwifi-3366.orig/net80211/ieee80211.c
> madwifi-3366/net80211/ieee80211.c ---
> madwifi-3366.orig/net80211/ieee80211.c	2008-01-30 18:50:16.000000000 -0500
> +++ madwifi-3366/net80211/ieee80211.c	2008-02-29 19:54:42.000000000 -0500
> @@ -451,14 +451,18 @@ ieee80211_vap_setup(struct ieee80211com
>  #endif
>
>  	vap->iv_caps = ic->ic_caps &~ IEEE80211_C_OPMODE;
> +	/* Means its unset yet via WE SIOCSIWRETRY ioctl */
> +	vap->iv_flags &= ~IEEE80211_F_SWRETRY;
> +
>  	switch (opmode) {
>  	case IEEE80211_M_STA:
>  		/* WDS/Repeater */
>  		if (flags & IEEE80211_NO_STABEACONS)
>  			vap->iv_flags_ext |= IEEE80211_FEXT_SWBMISS;
> +		vap->iv_caps |= IEEE80211_C_SWRETRY;
>  		break;
>  	case IEEE80211_M_IBSS:
> -		vap->iv_caps |= IEEE80211_C_IBSS;
> +		vap->iv_caps |= IEEE80211_C_IBSS | IEEE80211_C_SWRETRY;
>  		vap->iv_ath_cap &= ~IEEE80211_ATHC_XR;
>  		break;
>  	case IEEE80211_M_AHDEMO:
> diff -Naurp madwifi-3366.orig/net80211/ieee80211_wireless.c
> madwifi-3366/net80211/ieee80211_wireless.c ---
> madwifi-3366.orig/net80211/ieee80211_wireless.c	2008-01-30
> 22:42:51.000000000 -0500 +++
> madwifi-3366/net80211/ieee80211_wireless.c	2008-02-29 20:00:18.000000000
> -0500 @@ -1299,6 +1299,19 @@ ieee80211_ioctl_giwpower(struct net_devi
>  	return 0;
>  }
>
> +/* WE-21 added support for IW_RETRY_SHORT/IW_RETRY_LONG retry modifiers
> + * Note: IW_RETRY_SHORT/IW_RETRY_LONG was just a userspace improvement so
> + * we can just add the defines required for its support here and a user
> + * with an older kernel but new WE will still be able to benefit from this
> */ +#if WIRELESS_EXT < 21
> +/* Retry limits and lifetime flags available */
> +#ifndef IW_RETRY_LIFETIME /* Can't pinpoint when this guy was introduced
> */ +#define IW_RETRY_LIFETIME       0x2000  /* Maximum duration of retries
> in us */ +#endif /* IW_RETRY_LIFETIME */
> +#define IW_RETRY_SHORT          0x0010  /* Value is for short packets  */
> +#define IW_RETRY_LONG           0x0020  /* Value is for long packets */
> +#endif /* WIRELESS_EXT < 21 */
> +
>  static int
>  ieee80211_ioctl_siwretry(struct net_device *dev, struct iw_request_info
> *info, struct iw_param *rrq, char *extra)
> @@ -1311,24 +1324,33 @@ ieee80211_ioctl_siwretry(struct net_devi
>  			vap->iv_flags &= ~IEEE80211_F_SWRETRY;
>  			goto done;
>  		}
> +		/* Already disabled in iv_flags, nothing to do */
>  		return 0;
>  	}
>
>  	if ((vap->iv_caps & IEEE80211_C_SWRETRY) == 0)
>  		return -EOPNOTSUPP;
> +	if (rrq->value < 0)
> +		return -EINVAL;
>  	if (rrq->flags == IW_RETRY_LIMIT) {
>  		if (rrq->value >= 0) {
> -			vap->iv_txmin = rrq->value;
> -			vap->iv_txmax = rrq->value;	/* XXX */
> -			vap->iv_txlifetime = 0;		/* XXX */
> +			if (rrq->flags & IW_RETRY_SHORT)
> +				vap->iv_txmin = rrq->value;
> +			else if (rrq->flags & IW_RETRY_LONG)
> +				vap->iv_txmax = rrq->value;
> +			else {
> +				vap->iv_txmin = rrq->value;
> +				vap->iv_txmax = rrq->value;
> +			}
>  			vap->iv_flags |= IEEE80211_F_SWRETRY;
>  		} else {
>  			vap->iv_flags &= ~IEEE80211_F_SWRETRY;
>  		}
> -		return 0;
>  	}
> +	if (rrq->flags & IW_RETRY_LIFETIME)
> +		vap->iv_txlifetime = 0;
>  done:
> -	return IS_UP(vap->iv_dev) ? ic->ic_reset(vap->iv_dev) : 0;
> +	return IS_UP(ic->ic_dev) ? ic->ic_reset(ic->ic_dev) : 0;
>  }
>
>  static int