2019-09-04 06:16:54

by Wen Gong

Subject: [PATCH] mac80211: Store max_mtu in ieee80211_hw

Make it possibly for drivers to adjust the default mat_mtu
by storing it in the hardware struct.

Signed-off-by: Wen Gong <[email protected]>
---
include/net/mac80211.h | 3 +++
net/mac80211/iface.c | 5 ++++-
2 files changed, 7 insertions(+), 1 deletion(-)

diff --git a/include/net/mac80211.h b/include/net/mac80211.h
index d26da01..8545b03 100644
--- a/include/net/mac80211.h
+++ b/include/net/mac80211.h
@@ -2454,6 +2454,8 @@ enum ieee80211_hw_flags {
*
* @weight_multiplier: Driver specific airtime weight multiplier used while
* refilling deficit of each TXQ.
+ *
+ * @max_mtu: the max mtu could be set.
*/
struct ieee80211_hw {
struct ieee80211_conf conf;
@@ -2491,6 +2493,7 @@ struct ieee80211_hw {
u8 max_nan_de_entries;
u8 tx_sk_pacing_shift;
u8 weight_multiplier;
+ u32 max_mtu;
};

static inline bool _ieee80211_hw_check(struct ieee80211_hw *hw,
diff --git a/net/mac80211/iface.c b/net/mac80211/iface.c
index 06aac0a..00c33e6 100644
--- a/net/mac80211/iface.c
+++ b/net/mac80211/iface.c
@@ -1877,7 +1877,10 @@ int ieee80211_if_add(struct ieee80211_local *local, const char *name,

/* MTU range: 256 - 2304 */
ndev->min_mtu = 256;
- ndev->max_mtu = IEEE80211_MAX_DATA_LEN;
+ if (local->hw.max_mtu)
+ ndev->max_mtu = local->hw.max_mtu;
+ else
+ ndev->max_mtu = IEEE80211_MAX_DATA_LEN;

ret = register_netdevice(ndev);
if (ret) {
--
1.9.1

2019-09-04 07:04:34

by Johannes Berg

Subject: Re: [PATCH] mac80211: Store max_mtu in ieee80211_hw

On Wed, 2019-09-04 at 14:15 +0800, Wen Gong wrote:
> Make it possibly for drivers to adjust the default mat_mtu
> by storing it in the hardware struct.
>
> +++ b/net/mac80211/iface.c
> @@ -1877,7 +1877,10 @@ int ieee80211_if_add(struct ieee80211_local *local, const char *name,
>
> /* MTU range: 256 - 2304 */
> ndev->min_mtu = 256;
> - ndev->max_mtu = IEEE80211_MAX_DATA_LEN;
> + if (local->hw.max_mtu)
> + ndev->max_mtu = local->hw.max_mtu;
> + else
> + ndev->max_mtu = IEEE80211_MAX_DATA_LEN;

It seems (slightly) preferable to me to just initialize the value in
local->hw.max_mtu in alloc_hw(), so the driver can override it before
register_hw(), and then use it here unconditionally. Any particular
reason for it being this way?

johannes

2019-09-04 09:17:36

by Wen Gong

Subject: RE: [PATCH] mac80211: Store max_mtu in ieee80211_hw

> -----Original Message-----
> From: ath10k <[email protected]> On Behalf Of Johannes
> Berg
> Sent: Wednesday, September 4, 2019 3:04 PM
> To: Wen Gong <[email protected]>; [email protected]
> Cc: [email protected]
> Subject: [EXT] Re: [PATCH] mac80211: Store max_mtu in ieee80211_hw
>
Patch v2 sent, https://patchwork.kernel.org/patch/11129707/
> _______________________________________________
> ath10k mailing list
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