tcm_loop: Show address of tpg in configfs

In the past, the scsi_host's number wasn't shown anywhere, user have
to depends on vpg_83 to find the block device, which is also depends
on backstore implementation.

It's better for tcm_loop to provide necessary straightforward
information on locate the block device it created.

This patch would help to locate the block device created by tcm_loop.
The address would be shown at e.g.

  /sys/kernel/config/target/loopback/naa.60014059436855c1/tpgt_1/address

which would looks like "2:0:1", and the lun number can be found at
"/tpgt_1/lun/lun_0".  Altogether they formated the scsi address of
device as "2:0:1:0", which can be used to locate the device easily
through 'lsscsi'.

(Update to >= v4.4-rc1 configfs attribute usage - nab)

Signed-off-by: Sheng Yang <sheng@yasker.org>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
This commit is contained in:
Sheng Yang 2015-11-14 14:17:16 -08:00 committed by Nicholas Bellinger
parent 1ec218373b
commit 2628b352c3

View File

@ -1036,12 +1036,26 @@ static ssize_t tcm_loop_tpg_transport_status_store(struct config_item *item,
return -EINVAL;
}
static ssize_t tcm_loop_tpg_address_show(struct config_item *item,
char *page)
{
struct se_portal_group *se_tpg = to_tpg(item);
struct tcm_loop_tpg *tl_tpg = container_of(se_tpg,
struct tcm_loop_tpg, tl_se_tpg);
struct tcm_loop_hba *tl_hba = tl_tpg->tl_hba;
return snprintf(page, PAGE_SIZE, "%d:0:%d\n",
tl_hba->sh->host_no, tl_tpg->tl_tpgt);
}
CONFIGFS_ATTR(tcm_loop_tpg_, nexus);
CONFIGFS_ATTR(tcm_loop_tpg_, transport_status);
CONFIGFS_ATTR_RO(tcm_loop_tpg_, address);
static struct configfs_attribute *tcm_loop_tpg_attrs[] = {
&tcm_loop_tpg_attr_nexus,
&tcm_loop_tpg_attr_transport_status,
&tcm_loop_tpg_attr_address,
NULL,
};