scsi_transport_sas: add is_sas_attached() function

Adds a function designed to be callable any time (regardless of
whether the transport attributes are configured or not) which returns
true if the device is attached over a SAS transport.  The design of
this function is that transport specific functions can be embedded
within a

if (is_sas_attached(sdev)) {
	...
}

which would be compiled out (and thus eliminate the symbols) if SAS is
not configured.

Reviewed-by: Hannes Reinecke <hare@suse.com>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
This commit is contained in:
James Bottomley 2015-12-09 11:12:03 -08:00
parent ed94724bed
commit 3b91d09c1c
2 changed files with 25 additions and 0 deletions

View File

@ -340,6 +340,22 @@ static int do_sas_phy_delete(struct device *dev, void *data)
return 0;
}
/**
* is_sas_attached - check if device is SAS attached
* @sdev: scsi device to check
*
* returns true if the device is SAS attached
*/
int is_sas_attached(struct scsi_device *sdev)
{
struct Scsi_Host *shost = sdev->host;
return shost->transportt->host_attrs.ac.class ==
&sas_host_class.class;
}
EXPORT_SYMBOL(is_sas_attached);
/**
* sas_remove_children - tear down a devices SAS data structures
* @dev: device belonging to the sas object

View File

@ -10,6 +10,15 @@ struct scsi_transport_template;
struct sas_rphy;
struct request;
#if !IS_ENABLED(CONFIG_SCSI_SAS_ATTRS)
static inline int is_sas_attached(struct scsi_device *sdev)
{
return 0;
}
#else
extern int is_sas_attached(struct scsi_device *sdev);
#endif
static inline int sas_protocol_ata(enum sas_protocol proto)
{
return ((proto & SAS_PROTOCOL_SATA) ||