Re: [PATCH RESEND V2 3/7] scsi: storvsc: Untangle the storage protocol negotiation from the vmbus protocol negotiation.

From: Johannes Thumshirn <jthumshirn@suse.de>
To: "K. Y. Srinivasan" <kys@microsoft.com>,
	Keith Mange <keith.mange@microsoft.com>
Cc: gregkh@linuxfoundation.org, linux-kernel@vger.kernel.org,
	devel@linuxdriverproject.org, ohering@suse.com,
	jbottomley@parallels.com, hch@infradead.org,
	linux-scsi@vger.kernel.org, apw@canonical.com,
	vkuznets@redhat.com, jasowang@redhat.com
Subject: Re: [PATCH RESEND V2 3/7] scsi: storvsc: Untangle the storage protocol negotiation from the vmbus protocol negotiation.
Date: Thu, 13 Aug 2015 16:33:30 +0200	[thread overview]
Message-ID: <mqda8tv6yx1.fsf@c203.arch.suse.de> (raw)
In-Reply-To: <1439480632-11144-3-git-send-email-kys@microsoft.com> (K. Y. Srinivasan's message of "Thu, 13 Aug 2015 08:43:48 -0700")

"K. Y. Srinivasan" <kys@microsoft.com> writes:

> From: Keith Mange <keith.mange@microsoft.com>
>
> Currently we are making decisions based on vmbus protocol versions
> that have been negotiated; use storage potocol versions instead.
>
> Tested-by: Alex Ng <alexng@microsoft.com>
> Signed-off-by: Keith Mange <keith.mange@microsoft.com>
> Signed-off-by: K. Y. Srinivasan <kys@microsoft.com>
> ---
>  drivers/scsi/storvsc_drv.c |  109 +++++++++++++++++++++++++++++++++++---------
>  1 files changed, 87 insertions(+), 22 deletions(-)
>
> diff --git a/drivers/scsi/storvsc_drv.c b/drivers/scsi/storvsc_drv.c
> index 5f9d133..f29871e 100644
> --- a/drivers/scsi/storvsc_drv.c
> +++ b/drivers/scsi/storvsc_drv.c
> @@ -56,14 +56,18 @@
>   * V1 RC > 2008/1/31:  2.0
>   * Win7: 4.2
>   * Win8: 5.1
> + * Win8.1: 6.0
> + * Win10: 6.2
>   */
>  
>  #define VMSTOR_PROTO_VERSION(MAJOR_, MINOR_)	((((MAJOR_) & 0xff) << 8) | \
>  						(((MINOR_) & 0xff)))
>  
> +#define VMSTOR_PROTO_VERSION_WIN6	VMSTOR_PROTO_VERSION(2, 0)
>  #define VMSTOR_PROTO_VERSION_WIN7	VMSTOR_PROTO_VERSION(4, 2)
>  #define VMSTOR_PROTO_VERSION_WIN8	VMSTOR_PROTO_VERSION(5, 1)
> -
> +#define VMSTOR_PROTO_VERSION_WIN8_1	VMSTOR_PROTO_VERSION(6, 0)
> +#define VMSTOR_PROTO_VERSION_WIN10	VMSTOR_PROTO_VERSION(6, 2)
>  
>  /*  Packet structure describing virtual storage requests. */
>  enum vstor_packet_operation {
> @@ -205,6 +209,46 @@ struct vmscsi_request {
>  
>  
>  /*
> + * The list of storage protocols in order of preference.
> + */
> +struct vmstor_protocol {
> +	int protocol_version;
> +	int sense_buffer_size;
> +	int vmscsi_size_delta;
> +};
> +
> +#define VMSTOR_NUM_PROTOCOLS    5

can't you just use ARRAY_SIZE() here, so you don't have to touch the
constant every time a new protocol is appended to the list?

> +
> +const struct vmstor_protocol vmstor_protocols[VMSTOR_NUM_PROTOCOLS] = {
> +	{
> +		VMSTOR_PROTO_VERSION_WIN10,
> +		POST_WIN7_STORVSC_SENSE_BUFFER_SIZE,
> +		0
> +	},
> +	{
> +		VMSTOR_PROTO_VERSION_WIN8_1,
> +		POST_WIN7_STORVSC_SENSE_BUFFER_SIZE,
> +		0
> +	},
> +	{
> +		VMSTOR_PROTO_VERSION_WIN8,
> +		POST_WIN7_STORVSC_SENSE_BUFFER_SIZE,
> +		0
> +	},
> +	{
> +		VMSTOR_PROTO_VERSION_WIN7,
> +		PRE_WIN8_STORVSC_SENSE_BUFFER_SIZE,
> +		sizeof(struct vmscsi_win8_extension),
> +	},
> +	{
> +		VMSTOR_PROTO_VERSION_WIN6,
> +		PRE_WIN8_STORVSC_SENSE_BUFFER_SIZE,
> +		sizeof(struct vmscsi_win8_extension),
> +	}
> +};
> +

Thanks,
        Johannes
-- 
Johannes Thumshirn                                           Storage
jthumshirn@suse.de                                 +49 911 74053 689
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