target: Fix Task Aborted Status (TAS) handling

This patch addresses three of long standing issues wrt to Task
Aborted Status (TAS) handling.

The first is the incorrect assumption in core_tmr_handle_tas_abort()
that TASK_ABORTED status is sent for the task referenced by TMR
ABORT_TASK, and sending TASK_ABORTED status for TMR LUN_RESET on
the same nexus the LUN_RESET was received.

The second is to ensure the lun reference count is dropped within
transport_cmd_finish_abort() by calling transport_lun_remove_cmd()
before invoking transport_cmd_check_stop_to_fabric().

The last is to fix the delayed TAS handling to allow outstanding
WRITEs to complete before sending the TASK_ABORTED status. This
includes changing transport_check_aborted_status() to avoid
processing when SCF_SEND_DELAYED_TAS has not be set, and updating
transport_send_task_abort() to drop the SCF_SENT_DELAYED_TAS
check.

Signed-off-by: Alex Leung <amleung21@yahoo.com>
Cc: Alex Leung <amleung21@yahoo.com>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
This commit is contained in:
Alex Leung 2014-03-21 22:20:41 -07:00 committed by Nicholas Bellinger
parent f46d6a8a01
commit 68259b5aac
3 changed files with 18 additions and 16 deletions

View File

@ -87,14 +87,17 @@ static void core_tmr_handle_tas_abort(
struct se_cmd *cmd,
int tas)
{
bool remove = true;
/*
* TASK ABORTED status (TAS) bit support
*/
if ((tmr_nacl &&
(tmr_nacl == cmd->se_sess->se_node_acl)) || tas)
(tmr_nacl != cmd->se_sess->se_node_acl)) && tas) {
remove = false;
transport_send_task_abort(cmd);
}
transport_cmd_finish_abort(cmd, 0);
transport_cmd_finish_abort(cmd, remove);
}
static int target_check_cdb_and_preempt(struct list_head *list,
@ -150,18 +153,9 @@ void core_tmr_abort_task(
cancel_work_sync(&se_cmd->work);
transport_wait_for_tasks(se_cmd);
/*
* Now send SAM_STAT_TASK_ABORTED status for the referenced
* se_cmd descriptor..
*/
transport_send_task_abort(se_cmd);
/*
* Also deal with possible extra acknowledge reference..
*/
if (se_cmd->se_cmd_flags & SCF_ACK_KREF)
target_put_sess_cmd(se_sess, se_cmd);
target_put_sess_cmd(se_sess, se_cmd);
transport_cmd_finish_abort(se_cmd, true);
printk("ABORT_TASK: Sending TMR_FUNCTION_COMPLETE for"
" ref_tag: %d\n", ref_tag);

View File

@ -603,6 +603,9 @@ static void transport_lun_remove_cmd(struct se_cmd *cmd)
void transport_cmd_finish_abort(struct se_cmd *cmd, int remove)
{
if (cmd->se_cmd_flags & SCF_SE_LUN_CMD)
transport_lun_remove_cmd(cmd);
if (transport_cmd_check_stop_to_fabric(cmd))
return;
if (remove)
@ -2784,13 +2787,17 @@ int transport_check_aborted_status(struct se_cmd *cmd, int send_status)
if (!(cmd->transport_state & CMD_T_ABORTED))
return 0;
if (!send_status || (cmd->se_cmd_flags & SCF_SENT_DELAYED_TAS))
/*
* If cmd has been aborted but either no status is to be sent or it has
* already been sent, just return
*/
if (!send_status || !(cmd->se_cmd_flags & SCF_SEND_DELAYED_TAS))
return 1;
pr_debug("Sending delayed SAM_STAT_TASK_ABORTED status for CDB: 0x%02x ITT: 0x%08x\n",
cmd->t_task_cdb[0], cmd->se_tfo->get_task_tag(cmd));
cmd->se_cmd_flags |= SCF_SENT_DELAYED_TAS;
cmd->se_cmd_flags &= ~SCF_SEND_DELAYED_TAS;
cmd->scsi_status = SAM_STAT_TASK_ABORTED;
trace_target_cmd_complete(cmd);
cmd->se_tfo->queue_status(cmd);
@ -2804,7 +2811,7 @@ void transport_send_task_abort(struct se_cmd *cmd)
unsigned long flags;
spin_lock_irqsave(&cmd->t_state_lock, flags);
if (cmd->se_cmd_flags & (SCF_SENT_CHECK_CONDITION | SCF_SENT_DELAYED_TAS)) {
if (cmd->se_cmd_flags & (SCF_SENT_CHECK_CONDITION)) {
spin_unlock_irqrestore(&cmd->t_state_lock, flags);
return;
}
@ -2819,6 +2826,7 @@ void transport_send_task_abort(struct se_cmd *cmd)
if (cmd->data_direction == DMA_TO_DEVICE) {
if (cmd->se_tfo->write_pending_status(cmd) != 0) {
cmd->transport_state |= CMD_T_ABORTED;
cmd->se_cmd_flags |= SCF_SEND_DELAYED_TAS;
smp_mb__after_atomic_inc();
return;
}

View File

@ -162,7 +162,7 @@ enum se_cmd_flags_table {
SCF_SENT_CHECK_CONDITION = 0x00000800,
SCF_OVERFLOW_BIT = 0x00001000,
SCF_UNDERFLOW_BIT = 0x00002000,
SCF_SENT_DELAYED_TAS = 0x00004000,
SCF_SEND_DELAYED_TAS = 0x00004000,
SCF_ALUA_NON_OPTIMIZED = 0x00008000,
SCF_PASSTHROUGH_SG_TO_MEM_NOALLOC = 0x00020000,
SCF_ACK_KREF = 0x00040000,