iv/linux
1
0
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases Wiki Activity

target: Add TARGET_SCF_LOOKUP_LUN_FROM_TAG support for ABORT_TASK

Browse Source 
This patch introduces support in target_submit_tmr() for locating a
unpacked_lun from an existing se_cmd->tag during ABORT_TASK.

When TARGET_SCF_LOOKUP_LUN_FROM_TAG is set, target_submit_tmr()
will do the extra lookup via target_lookup_lun_from_tag() and
subsequently invoke transport_lookup_tmr_lun() so a proper
percpu se_lun->lun_ref is taken before workqueue dispatch into
se_device->tmr_wq happens.

Aside from the extra target_lookup_lun_from_tag(), the existing
code-path remains unchanged.

Reviewed-by: Himanshu Madhani <himanshu.madhani@cavium.com>
Reviewed-by: Quinn Tran <quinn.tran@cavium.com>
Cc: Mike Christie <mchristi@redhat.com>
Cc: Hannes Reinecke <hare@suse.com>
Cc: Christoph Hellwig <hch@lst.de>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
This commit is contained in:
Nicholas Bellinger 2017-06-03 06:55:50 -07:00
parent eeb64d239e
commit 5465e7d3b9
2 changed files with 46 additions and 10 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

53
drivers/target/target_core_transport.c
View File

@ -1594,6 +1594,29 @@ static void target_complete_tmr_failure(struct work_struct *work)
transport_cmd_check_stop_to_fabric(se_cmd);
}
static bool target_lookup_lun_from_tag(struct se_session *se_sess, u64 tag,
u64 *unpacked_lun)
{
struct se_cmd *se_cmd;
unsigned long flags;
bool ret = false;
spin_lock_irqsave(&se_sess->sess_cmd_lock, flags);
list_for_each_entry(se_cmd, &se_sess->sess_cmd_list, se_cmd_list) {
if (se_cmd->se_cmd_flags & SCF_SCSI_TMR_CDB)
continue;
if (se_cmd->tag == tag) {
*unpacked_lun = se_cmd->orig_fe_lun;
ret = true;
break;
}
}
spin_unlock_irqrestore(&se_sess->sess_cmd_lock, flags);
return ret;
}
/**
* target_submit_tmr - lookup unpacked lun and submit uninitialized se_cmd
* for TMR CDBs
@ -1641,19 +1664,31 @@ int target_submit_tmr(struct se_cmd *se_cmd, struct se_session *se_sess,
core_tmr_release_req(se_cmd->se_tmr_req);
return ret;
}
/*
* If this is ABORT_TASK with no explicit fabric provided LUN,
* go ahead and search active session tags for a match to figure
* out unpacked_lun for the original se_cmd.
*/
if (tm_type == TMR_ABORT_TASK && (flags & TARGET_SCF_LOOKUP_LUN_FROM_TAG)) {
if (!target_lookup_lun_from_tag(se_sess, tag, &unpacked_lun))
goto failure;
}
ret = transport_lookup_tmr_lun(se_cmd, unpacked_lun);
if (ret) {
/*
* For callback during failure handling, push this work off
* to process context with TMR_LUN_DOES_NOT_EXIST status.
*/
INIT_WORK(&se_cmd->work, target_complete_tmr_failure);
schedule_work(&se_cmd->work);
return 0;
}
if (ret)
goto failure;
transport_generic_handle_tmr(se_cmd);
return 0;
/*
* For callback during failure handling, push this work off
* to process context with TMR_LUN_DOES_NOT_EXIST status.
*/
failure:
INIT_WORK(&se_cmd->work, target_complete_tmr_failure);
schedule_work(&se_cmd->work);
return 0;
}
EXPORT_SYMBOL(target_submit_tmr);

3
include/target/target_core_base.h
View File

@ -188,7 +188,8 @@ enum target_sc_flags_table {
TARGET_SCF_BIDI_OP = 0x01,
TARGET_SCF_ACK_KREF = 0x02,
TARGET_SCF_UNKNOWN_SIZE = 0x04,
TARGET_SCF_USE_CPUID = 0x08,
TARGET_SCF_USE_CPUID = 0x08,
TARGET_SCF_LOOKUP_LUN_FROM_TAG = 0x10,
};
/* fabric independent task management function values */