linux-toradex.git/drivers/target, branch v4.4.38

target: Don't override EXTENDED_COPY xcopy_pt_cmd SCSI status code

2016-10-28T07:01:36+00:00

commit 926317de33998c112c5510301868ea9aa34097e2 upstream.

This patch addresses a bug where a local EXTENDED_COPY WRITE or READ
backend I/O request would always return SAM_STAT_CHECK_CONDITION,
even if underlying xcopy_pt_cmd->se_cmd generated a different
SCSI status code.

ESX host environments expect to hit SAM_STAT_RESERVATION_CONFLICT
for certain scenarios, and SAM_STAT_CHECK_CONDITION results in
non-retriable status for these cases.

Tested on v4.1.y with ESX v5.5u2+ with local IBLOCK backend copy.

Reported-by: Nixon Vincent 
Tested-by: Nixon Vincent 
Cc: Nixon Vincent 
Tested-by: Dinesh Israni 
Signed-off-by: Dinesh Israni 
Cc: Dinesh Israni 
Signed-off-by: Nicholas Bellinger 
Signed-off-by: Greg Kroah-Hartman

target: Make EXTENDED_COPY 0xe4 failure return COPY TARGET DEVICE NOT REACHABLE

2016-10-28T07:01:36+00:00

commit 449a137846c84829a328757cd21fd9ca65c08519 upstream.

This patch addresses a bug where EXTENDED_COPY across multiple LUNs
results in a CHECK_CONDITION when the source + destination are not
located on the same physical node.

ESX Host environments expect sense COPY_ABORTED w/ COPY TARGET DEVICE
NOT REACHABLE to be returned when this occurs, in order to signal
fallback to local copy method.

As described in section 6.3.3 of spc4r22:

  "If it is not possible to complete processing of a segment because the
   copy manager is unable to establish communications with a copy target
   device, because the copy target device does not respond to INQUIRY,
   or because the data returned in response to INQUIRY indicates
   an unsupported logical unit, then the EXTENDED COPY command shall be
   terminated with CHECK CONDITION status, with the sense key set to
   COPY ABORTED, and the additional sense code set to COPY TARGET DEVICE
   NOT REACHABLE."

Tested on v4.1.y with ESX v5.5u2+ with BlockCopy across multiple nodes.

Reported-by: Nixon Vincent 
Tested-by: Nixon Vincent 
Cc: Nixon Vincent 
Tested-by: Dinesh Israni 
Signed-off-by: Dinesh Israni 
Cc: Dinesh Israni 
Signed-off-by: Nicholas Bellinger 
Signed-off-by: Greg Kroah-Hartman

target: Re-add missing SCF_ACK_KREF assignment in v4.1.y

2016-10-28T07:01:35+00:00

commit 527268df31e57cf2b6d417198717c6d6afdb1e3e upstream.

This patch fixes a regression in >= v4.1.y code where the original
SCF_ACK_KREF assignment in target_get_sess_cmd() was dropped upstream
in commit 054922bb, but the series for addressing TMR ABORT_TASK +
LUN_RESET with fabric session reinstatement in commit febe562c20 still
depends on this code in transport_cmd_finish_abort().

The regression manifests itself as a se_cmd->cmd_kref +1 leak, where
ABORT_TASK + LUN_RESET can hang indefinately for a specific I_T session
for drivers using SCF_ACK_KREF, resulting in hung kthreads.

This patch has been verified with v4.1.y code.

Reported-by: Vaibhav Tandon 
Tested-by: Vaibhav Tandon 
Cc: Vaibhav Tandon 
Signed-off-by: Nicholas Bellinger 
Signed-off-by: Greg Kroah-Hartman

target: Fix ordered task CHECK_CONDITION early exception handling

2016-08-20T16:09:26+00:00

commit 410c29dfbfdf73d0d0b5d14a21868ab038eca703 upstream.

If a Simple command is sent with a failure, target_setup_cmd_from_cdb
returns with TCM_UNSUPPORTED_SCSI_OPCODE or TCM_INVALID_CDB_FIELD.

So in the cases where target_setup_cmd_from_cdb returns an error, we
never get far enough to call target_execute_cmd to increment simple_cmds.
Since simple_cmds isn't incremented, the result of the failure from
target_setup_cmd_from_cdb causes transport_generic_request_failure to
decrement simple_cmds, due to call to transport_complete_task_attr.

With this dev->simple_cmds or dev->dev_ordered_sync is now -1, not 0.
So when a subsequent command with an Ordered Task is sent, it causes
a hang, since dev->simple_cmds is at -1.

Tested-by: Bryant G. Ly 
Signed-off-by: Bryant G. Ly 
Tested-by: Michael Cyr 
Signed-off-by: Michael Cyr 
Signed-off-by: Nicholas Bellinger 
Signed-off-by: Greg Kroah-Hartman

target: Fix max_unmap_lba_count calc overflow

2016-08-20T16:09:26+00:00

commit ea263c7fada4af8ec7fe5fcfd6e7d7705a89351b upstream.

max_discard_sectors only 32bits, and some non scsi backend
devices will set this to the max 0xffffffff, so we can end up
overflowing during the max_unmap_lba_count calculation.

This fixes a regression caused by my patch:

commit 8a9ebe717a133ba7bc90b06047f43cc6b8bcb8b3
Author: Mike Christie 
Date:   Mon Jan 18 14:09:27 2016 -0600

    target: Fix WRITE_SAME/DISCARD conversion to linux 512b sectors

which can result in extra discards being sent to due the overflow
causing max_unmap_lba_count to be smaller than what the backing
device can actually support.

Signed-off-by: Mike Christie 
Reviewed-by: Bart Van Assche 
Signed-off-by: Nicholas Bellinger 
Signed-off-by: Greg Kroah-Hartman

target: Fix race between iscsi-target connection shutdown + ABORT_TASK

2016-08-20T16:09:26+00:00

commit 064cdd2d91c2805d788876082f31cc63506f22c3 upstream.

This patch fixes a race in iscsit_release_commands_from_conn() ->
iscsit_free_cmd() -> transport_generic_free_cmd() + wait_for_tasks=1,
where CMD_T_FABRIC_STOP could end up being set after the final
kref_put() is called from core_tmr_abort_task() context.

This results in transport_generic_free_cmd() blocking indefinately
on se_cmd->cmd_wait_comp, because the target_release_cmd_kref()
check for CMD_T_FABRIC_STOP returns false.

To address this bug, make iscsit_release_commands_from_conn()
do list_splice and set CMD_T_FABRIC_STOP early while holding
iscsi_conn->cmd_lock.  Also make iscsit_aborted_task() only
remove iscsi_cmd_t if CMD_T_FABRIC_STOP has not already been
set.

Finally in target_release_cmd_kref(), only honor fabric_stop
if CMD_T_ABORTED has been set.

Cc: Mike Christie 
Cc: Quinn Tran 
Cc: Himanshu Madhani 
Cc: Christoph Hellwig 
Cc: Hannes Reinecke 
Tested-by: Nicholas Bellinger 
Signed-off-by: Nicholas Bellinger 
Signed-off-by: Greg Kroah-Hartman

target: Fix missing complete during ABORT_TASK + CMD_T_FABRIC_STOP

2016-08-20T16:09:26+00:00

commit 5e2c956b8aa24d4f33ff7afef92d409eed164746 upstream.

During transport_generic_free_cmd() with a concurrent TMR
ABORT_TASK and shutdown CMD_T_FABRIC_STOP bit set, the
caller will be blocked on se_cmd->cmd_wait_stop completion
until the final kref_put() -> target_release_cmd_kref()
has been invoked to call complete().

However, when ABORT_TASK is completed with FUNCTION_COMPLETE
in core_tmr_abort_task(), the aborted se_cmd will have already
been removed from se_sess->sess_cmd_list via list_del_init().

This results in target_release_cmd_kref() hitting the
legacy list_empty() == true check, invoking ->release_cmd()
but skipping complete() to wakeup se_cmd->cmd_wait_stop
blocked earlier in transport_generic_free_cmd() code.

To address this bug, it's safe to go ahead and drop the
original list_empty() check so that fabric_stop invokes
the complete() as expected, since list_del_init() can
safely be used on a empty list.

Cc: Mike Christie 
Cc: Quinn Tran 
Cc: Himanshu Madhani 
Cc: Christoph Hellwig 
Cc: Hannes Reinecke 
Tested-by: Nicholas Bellinger 
Signed-off-by: Nicholas Bellinger 
Signed-off-by: Greg Kroah-Hartman

target: Fix ordered task target_setup_cmd_from_cdb exception hang

2016-08-20T16:09:26+00:00

commit dff0ca9ea7dc8be2181a62df4a722c32ce68ff4a upstream.

If a command with a Simple task attribute is failed due to a Unit
Attention, then a subsequent command with an Ordered task attribute
will hang forever.  The reason for this is that the Unit Attention
status is checked for in target_setup_cmd_from_cdb, before the call
to target_execute_cmd, which calls target_handle_task_attr, which
in turn increments dev->simple_cmds.

However, transport_generic_request_failure still calls
transport_complete_task_attr, which will decrement dev->simple_cmds.
In this case, simple_cmds is now -1.  So when a command with the
Ordered task attribute is sent, target_handle_task_attr sees that
dev->simple_cmds is not 0, so it decides it can't execute the
command until all the (nonexistent) Simple commands have completed.

Reported-by: Michael Cyr 
Tested-by: Michael Cyr 
Reported-by: Bryant G. Ly 
Tested-by: Bryant G. Ly 
Signed-off-by: Nicholas Bellinger 
Signed-off-by: Greg Kroah-Hartman

iscsi-target: Fix panic when adding second TCP connection to iSCSI session

2016-08-20T16:09:26+00:00

commit 8abc718de6e9e52d8a6bfdb735060554aeae25e4 upstream.

In MC/S scenario, the conn->sess has been set NULL in
iscsi_login_non_zero_tsih_s1 when the second connection comes here,
then kernel panic.

The conn->sess will be assigned in iscsi_login_non_zero_tsih_s2. So
we should check whether it's NULL before calling.

Signed-off-by: Feng Li 
Tested-by: Sumit Rai 
Signed-off-by: Nicholas Bellinger 
Signed-off-by: Greg Kroah-Hartman

target: Fix target_release_cmd_kref shutdown comp leak

2016-04-12T16:09:02+00:00

commit 5e47f1985d7107331c3f64fb3ec83d66fd73577e upstream.

This patch fixes an active I/O shutdown bug for fabric
drivers using target_wait_for_sess_cmds(), where se_cmd
descriptor shutdown would result in hung tasks waiting
indefinitely for se_cmd->cmd_wait_comp to complete().

To address this bug, drop the incorrect list_del_init()
usage in target_wait_for_sess_cmds() and always complete()
during se_cmd target_release_cmd_kref() put, in order to
let caller invoke the final fabric release callback
into se_cmd->se_tfo->release_cmd() code.

Reported-by: Himanshu Madhani 
Tested-by: Himanshu Madhani 
Signed-off-by: Himanshu Madhani 
Signed-off-by: Nicholas Bellinger 
Signed-off-by: Greg Kroah-Hartman