[dm-devel] [PATCH v2 3/9] libmultipath: alua: try to retrieve inquiry data from sysfs

[Hannes Reinecke]

On 3/15/19 6:19 PM, Martin Wilck wrote:
> This can avoid IO while configuring the path prioritizer.
> The alua prioritizer avoids reading from sysfs for a reason
> (see commit 7e2f46d3), but this applies only to RTPG / STPG,
> not to INQUIRY calls.
> 
> Cc: Steve.Schremmer at netapp.com
> Cc: NetApp RDAC team <ng-eseries-upstream-maintainers at netapp.com>
> Cc: Hannes Reinecke <hare at suse.com>
> Signed-off-by: Martin Wilck <mwilck at suse.com>
> ---
>   libmultipath/prioritizers/alua_rtpg.c | 17 +++++++++++++++++
>   1 file changed, 17 insertions(+)
> 
> diff --git a/libmultipath/prioritizers/alua_rtpg.c b/libmultipath/prioritizers/alua_rtpg.c
> index d9215a88..271a019d 100644
> --- a/libmultipath/prioritizers/alua_rtpg.c
> +++ b/libmultipath/prioritizers/alua_rtpg.c
> @@ -188,6 +188,23 @@ retry:
>   int do_inquiry(const struct path *pp, int evpd, unsigned int codepage,
>   	       void *resp, int resplen, unsigned int timeout)
>   {
> +	struct udev_device *ud;
> +
> +	ud = udev_device_get_parent_with_subsystem_devtype(pp->udev, "scsi",
> +							   "scsi_device");
> +	if (ud != NULL) {
> +		int rc;
> +
> +		if (!evpd)
> +			rc = sysfs_get_inquiry(ud, resp, resplen);
> +		else
> +			rc = sysfs_get_vpd(ud, codepage, resp, resplen);
> +
> +		if (rc >= 0) {
> +			PRINT_HEX((unsigned char *) resp, resplen);
> +			return 0;
> +		}
> +	}
>   	return do_inquiry_sg(pp->fd, evpd, codepage, resp, resplen, timeout);
>   }
>   
> 
Don't you need to do a udev_device_put() or somesuch?

Other than that:

Reviewed-by: Hannes Reinecke <hare at suse.com>

Cheers,

Hannes
-- 
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