RE: [PATCH v2] drivers: ipmi: Support for both IPMB Req and Resp

[Asmaa Mnebhi <Asmaa@mellanox.com>]

Thanks Corey!

-----Original Message-----
From: Corey Minyard <tcminyard@gmail.com> On Behalf Of Corey Minyard
Sent: Thursday, November 7, 2019 8:34 AM
To: Vijay Khemka <vijaykhemka@fb.com>
Cc: Arnd Bergmann <arnd@arndb.de>; Greg Kroah-Hartman <gregkh@linuxfoundation.org>; openipmi-developer@lists.sourceforge.net; linux-kernel@vger.kernel.org; cminyard@mvista.com; Asmaa Mnebhi <Asmaa@mellanox.com>; joel@jms.id.au; linux-aspeed@lists.ozlabs.org; sdasari@fb.com
Subject: Re: [PATCH v2] drivers: ipmi: Support for both IPMB Req and Resp

On Wed, Nov 06, 2019 at 10:29:21AM -0800, Vijay Khemka wrote:
> Removed check for request or response in IPMB packets coming from 
> device as well as from host. Now it supports both way communication to 
> device via IPMB. Both request and response will be passed to 
> application.
> 
> Signed-off-by: Vijay Khemka <vijaykhemka@fb.com>

Thanks, this is in my for-next tree now.  Asnaam, I took your previous comments as a "Reviewed-by", if that is ok.

-corey

> ---
>  drivers/char/ipmi/ipmb_dev_int.c | 31 +++++++++----------------------
>  1 file changed, 9 insertions(+), 22 deletions(-)
> 
> diff --git a/drivers/char/ipmi/ipmb_dev_int.c 
> b/drivers/char/ipmi/ipmb_dev_int.c
> index 285e0b8f9a97..ae3bfba27526 100644
> --- a/drivers/char/ipmi/ipmb_dev_int.c
> +++ b/drivers/char/ipmi/ipmb_dev_int.c
> @@ -133,9 +133,6 @@ static ssize_t ipmb_write(struct file *file, const char __user *buf,
>  	rq_sa = GET_7BIT_ADDR(msg[RQ_SA_8BIT_IDX]);
>  	netf_rq_lun = msg[NETFN_LUN_IDX];
>  
> -	if (!(netf_rq_lun & NETFN_RSP_BIT_MASK))
> -		return -EINVAL;
> -
>  	/*
>  	 * subtract rq_sa and netf_rq_lun from the length of the msg passed to
>  	 * i2c_smbus_xfer
> @@ -203,25 +200,16 @@ static u8 ipmb_verify_checksum1(struct ipmb_dev *ipmb_dev, u8 rs_sa)
>  		ipmb_dev->request.checksum1);
>  }
>  
> -static bool is_ipmb_request(struct ipmb_dev *ipmb_dev, u8 rs_sa)
> +/*
> + * Verify if message has proper ipmb header with minimum length
> + * and correct checksum byte.
> + */
> +static bool is_ipmb_msg(struct ipmb_dev *ipmb_dev, u8 rs_sa)
>  {
> -	if (ipmb_dev->msg_idx >= IPMB_REQUEST_LEN_MIN) {
> -		if (ipmb_verify_checksum1(ipmb_dev, rs_sa))
> -			return false;
> +	if ((ipmb_dev->msg_idx >= IPMB_REQUEST_LEN_MIN) &&
> +	   (!ipmb_verify_checksum1(ipmb_dev, rs_sa)))
> +		return true;
>  
> -		/*
> -		 * Check whether this is an IPMB request or
> -		 * response.
> -		 * The 6 MSB of netfn_rs_lun are dedicated to the netfn
> -		 * while the remaining bits are dedicated to the lun.
> -		 * If the LSB of the netfn is cleared, it is associated
> -		 * with an IPMB request.
> -		 * If the LSB of the netfn is set, it is associated with
> -		 * an IPMB response.
> -		 */
> -		if (!(ipmb_dev->request.netfn_rs_lun & NETFN_RSP_BIT_MASK))
> -			return true;
> -	}
>  	return false;
>  }
>  
> @@ -273,8 +261,7 @@ static int ipmb_slave_cb(struct i2c_client 
> *client,
>  
>  	case I2C_SLAVE_STOP:
>  		ipmb_dev->request.len = ipmb_dev->msg_idx;
> -
> -		if (is_ipmb_request(ipmb_dev, GET_8BIT_ADDR(client->addr)))
> +		if (is_ipmb_msg(ipmb_dev, GET_8BIT_ADDR(client->addr)))
>  			ipmb_handle_request(ipmb_dev);
>  		break;
>  
> --
> 2.17.1
>