Re: [PATCH v4 20/28] wan: qmc_hdlc: Add runtime timeslots changes support

[Christophe JAILLET]

Le 18/08/2023 à 18:39, Christophe Leroy a écrit :
> From: Herve Codina <herve.codina@xxxxxxxxxxx>
>
> QMC channels support runtime timeslots changes but nothing is done at
> the QMC HDLC driver to handle these changes.
>
> Use existing IFACE ioctl in order to configure the timeslots to use.
>
> Signed-off-by: Herve Codina <herve.codina@xxxxxxxxxxx>
> Reviewed-by: Christophe Leroy <christophe.leroy@xxxxxxxxxx>
> Signed-off-by: Christophe Leroy <christophe.leroy@xxxxxxxxxx>
> ---

Hi,

a few nits below, should there be a v5.

>   drivers/net/wan/fsl_qmc_hdlc.c | 169 ++++++++++++++++++++++++++++++++-
>   1 file changed, 168 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/net/wan/fsl_qmc_hdlc.c b/drivers/net/wan/fsl_qmc_hdlc.c
> index 4f84ac5fc63e..4b8cb5761fd1 100644
> --- a/drivers/net/wan/fsl_qmc_hdlc.c
> +++ b/drivers/net/wan/fsl_qmc_hdlc.c
> @@ -32,6 +32,7 @@ struct qmc_hdlc {
>   	struct qmc_hdlc_desc tx_descs[8];
>   	unsigned int tx_out;
>   	struct qmc_hdlc_desc rx_descs[4];
> +	u32 slot_map;
>   };
>   
>   static inline struct qmc_hdlc *netdev_to_qmc_hdlc(struct net_device *netdev)
> @@ -202,6 +203,162 @@ static netdev_tx_t qmc_hdlc_xmit(struct sk_buff *skb, struct net_device *netdev)
>   	return NETDEV_TX_OK;
>   }
>   
> +static int qmc_hdlc_xlate_slot_map(struct qmc_hdlc *qmc_hdlc,
> +				   u32 slot_map, struct qmc_chan_ts_info *ts_info)
> +{
> +	u64 ts_mask_avail;
> +	unsigned int bit;
> +	unsigned int i;
> +	u64 ts_mask;
> +	u64 map = 0;

This init looks useless.

> +
> +	/* Tx and Rx masks must be identical */
> +	if (ts_info->rx_ts_mask_avail != ts_info->tx_ts_mask_avail) {
> +		dev_err(qmc_hdlc->dev, "tx and rx available timeslots mismatch (0x%llx, 0x%llx)\n",
> +			ts_info->rx_ts_mask_avail, ts_info->tx_ts_mask_avail);
> +		return -EINVAL;
> +	}
> +
> +	ts_mask_avail = ts_info->rx_ts_mask_avail;
> +	ts_mask = 0;
> +	map = slot_map;
> +	bit = 0;
> +	for (i = 0; i < 64; i++) {
> +		if (ts_mask_avail & BIT_ULL(i)) {
> +			if (map & BIT_ULL(bit))
> +				ts_mask |= BIT_ULL(i);
> +			bit++;
> +		}
> +	}
> +
> +	if (hweight64(ts_mask) != hweight64(map)) {
> +		dev_err(qmc_hdlc->dev, "Cannot translate timeslots 0x%llx -> (0x%llx,0x%llx)\n",
> +			map, ts_mask_avail, ts_mask);
> +		return -EINVAL;
> +	}
> +
> +	ts_info->tx_ts_mask = ts_mask;
> +	ts_info->rx_ts_mask = ts_mask;
> +	return 0;
> +}
> +
> +static int qmc_hdlc_xlate_ts_info(struct qmc_hdlc *qmc_hdlc,
> +				  const struct qmc_chan_ts_info *ts_info, u32 *slot_map)
> +{
> +	u64 ts_mask_avail;
> +	unsigned int bit;
> +	unsigned int i;
> +	u64 ts_mask;
> +	u64 map = 0;

This init looks useless.

> +
> +	/* Tx and Rx masks must be identical */
> +	if (ts_info->rx_ts_mask_avail != ts_info->tx_ts_mask_avail) {
> +		dev_err(qmc_hdlc->dev, "tx and rx available timeslots mismatch (0x%llx, 0x%llx)\n",
> +			ts_info->rx_ts_mask_avail, ts_info->tx_ts_mask_avail);
> +		return -EINVAL;
> +	}
> +	if (ts_info->rx_ts_mask != ts_info->tx_ts_mask) {
> +		dev_err(qmc_hdlc->dev, "tx and rx timeslots mismatch (0x%llx, 0x%llx)\n",
> +			ts_info->rx_ts_mask, ts_info->tx_ts_mask);
> +		return -EINVAL;
> +	}
> +
> +	ts_mask_avail = ts_info->rx_ts_mask_avail;
> +	ts_mask = ts_info->rx_ts_mask;
> +	map = 0;
> +	bit = 0;
> +	for (i = 0; i < 64; i++) {
> +		if (ts_mask_avail & BIT_ULL(i)) {
> +			if (ts_mask & BIT_ULL(i))
> +				map |= BIT_ULL(bit);
> +			bit++;
> +		}
> +	}
> +
> +	if (hweight64(ts_mask) != hweight64(map)) {
> +		dev_err(qmc_hdlc->dev, "Cannot translate timeslots (0x%llx,0x%llx) -> 0x%llx\n",
> +			ts_mask_avail, ts_mask, map);
> +		return -EINVAL;
> +	}
> +
> +	if (map >= BIT_ULL(32)) {
> +		dev_err(qmc_hdlc->dev, "Slot map out of 32bit (0x%llx,0x%llx) -> 0x%llx\n",
> +			ts_mask_avail, ts_mask, map);
> +		return -EINVAL;
> +	}
> +
> +	*slot_map = map;
> +	return 0;
> +}

...

> +static int qmc_hdlc_ioctl(struct net_device *netdev, struct if_settings *ifs)
> +{
> +	struct qmc_hdlc *qmc_hdlc = netdev_to_qmc_hdlc(netdev);
> +	te1_settings te1;
> +
> +	switch (ifs->type) {
> +	case IF_GET_IFACE:
> +		ifs->type = IF_IFACE_E1;
> +		if (ifs->size < sizeof(te1)) {
> +			if (!ifs->size)
> +				return 0; /* only type requested */
> +
> +			ifs->size = sizeof(te1); /* data size wanted */
> +			return -ENOBUFS;
> +		}
> +
> +		memset(&te1, 0, sizeof(te1));
> +
> +		/* Update slot_map */
> +		te1.slot_map = qmc_hdlc->slot_map;
> +
> +		if (copy_to_user(ifs->ifs_ifsu.te1, &te1,  sizeof(te1)))

                                                         ~~
Extra space.

> +			return -EFAULT;
> +		return 0;
> +
> +	case IF_IFACE_E1:
> +	case IF_IFACE_T1:
> +		if (!capable(CAP_NET_ADMIN))
> +			return -EPERM;
> +
> +		if (netdev->flags & IFF_UP)
> +			return -EBUSY;
> +
> +		if (copy_from_user(&te1, ifs->ifs_ifsu.te1, sizeof(te1)))
> +			return -EFAULT;
> +
> +		return qmc_hdlc_set_iface(qmc_hdlc, ifs->type, &te1);
> +
> +	default:
> +		return hdlc_ioctl(netdev, ifs);
> +	}
> +}

...