On Fri, Jun 14, 2024 at 04:52:42AM -0700, Breno Leitao wrote: > Embedding net_device into structures prohibits the usage of flexible > arrays in the net_device structure. For more details, see the discussion > at [1]. > > Un-embed the net_devices from struct mt76_dev by converting them > into pointers, and allocating them dynamically. Use the leverage > alloc_netdev_dummy() to allocate the net_device object at > mt76_dma_init(). > > The free of the device occurs at mt76_dma_cleanup(). > > Link: https://lore.kernel.org/all/20240229225910.79e224cf@xxxxxxxxxx/ [1] > Signed-off-by: Breno Leitao <leitao@xxxxxxxxxx> > --- > > PS: Due to the lack of hardware, this patch was not tested on a real > hardware, unfortunately. > > PS2: this is the last driver that is still using embedded netdevices. ... > diff --git a/drivers/net/wireless/mediatek/mt76/dma.h b/drivers/net/wireless/mediatek/mt76/dma.h > index 1de5a2b20f74..6454a5eca13e 100644 > --- a/drivers/net/wireless/mediatek/mt76/dma.h > +++ b/drivers/net/wireless/mediatek/mt76/dma.h > @@ -116,4 +116,9 @@ mt76_dma_should_drop_buf(bool *drop, u32 ctrl, u32 buf1, u32 info) > } > } > > +static inline struct mt76_dev *mt76_from_netdev(struct net_device *dev) > +{ > + return *(struct mt76_dev **)netdev_priv(dev); > +} > + > #endif Hi Breno, I agree that the above is correct, but I wonder if somehow it is nicer to avoid explicit casts and instead take advantage of implicit casting too and from void *. Maybe something like this: static inline struct mt76_dev *mt76_from_netdev(struct net_device *dev) { struct mt76_dev **priv; priv = netdev_priv(dev); return *priv; } Further, some of the callers of mt76_from_netdev() cast the return value to (struct mt7615_dev *). Which seems a bit awkward seeing as it was very recently a void * (i.e. netdev_priv() returns void *). I wonder if something like this makes sense, which I believe would avoid the need for any callers to cast. static inline void *mt76_priv(struct net_device *dev) { struct mt76_dev **priv; priv = netdev_priv(dev); return *priv; } Ideas above compile tested only. Other than the above, which is clearly more about style than substance, this patch looks good to me. Reviewed-by: Simon Horman <horms@xxxxxxxxxx>
