linux-toradex.git/include/target, branch v6.4-rc2

Merge patch series "target: TMF and recovery fixes"

2023-03-24T21:39:15+00:00

Mike Christie  says:

The following patches apply over Martin's 6.4 branches and Linus's tree.
They fix a couple regressions in iscsit that occur when there are TMRs
executing and a connection is closed. It also includes Dimitry's fixes in
related code paths for cmd cleanup when ERL2 is used and the write pending
hang during conn cleanup.

This version of the patchset brings it back to just regressions and fixes
for bugs we have a lot of users hitting. I'm going to fix isert and get it
hooked into iscsit properly in a second patchset, because this one was
getting so large. I've also moved my cleanup type of patches for a 3rd
patchset.

Link: https://lore.kernel.org/r/20230319015620.96006-1-michael.christie@oracle.com
Signed-off-by: Martin K. Petersen

scsi: target: Fix multiple LUN_RESET handling

2023-03-24T21:32:23+00:00

This fixes a bug where an initiator thinks a LUN_RESET has cleaned up
running commands when it hasn't. The bug was added in commit 51ec502a3266
("target: Delete tmr from list before processing").

The problem occurs when:

 1. We have N I/O cmds running in the target layer spread over 2 sessions.

 2. The initiator sends a LUN_RESET for each session.

 3. session1's LUN_RESET loops over all the running commands from both
    sessions and moves them to its local drain_task_list.

 4. session2's LUN_RESET does not see the LUN_RESET from session1 because
    the commit above has it remove itself. session2 also does not see any
    commands since the other reset moved them off the state lists.

 5. sessions2's LUN_RESET will then complete with a successful response.

 6. sessions2's inititor believes the running commands on its session are
    now cleaned up due to the successful response and cleans up the running
    commands from its side. It then restarts them.

 7. The commands do eventually complete on the backend and the target
    starts to return aborted task statuses for them. The initiator will
    either throw a invalid ITT error or might accidentally lookup a new
    task if the ITT has been reallocated already.

Fix the bug by reverting the patch, and serialize the execution of
LUN_RESETs and Preempt and Aborts.

Also prevent us from waiting on LUN_RESETs in core_tmr_drain_tmr_list,
because it turns out the original patch fixed a bug that was not
mentioned. For LUN_RESET1 core_tmr_drain_tmr_list can see a second
LUN_RESET and wait on it. Then the second reset will run
core_tmr_drain_tmr_list and see the first reset and wait on it resulting in
a deadlock.

Fixes: 51ec502a3266 ("target: Delete tmr from list before processing")
Signed-off-by: Mike Christie 
Link: https://lore.kernel.org/r/20230319015620.96006-8-michael.christie@oracle.com
Signed-off-by: Martin K. Petersen

scsi: target: iscsit: isert: Alloc per conn cmd counter

2023-03-24T21:32:23+00:00

This has iscsit allocate a per conn cmd counter and converts iscsit/isert
to use it instead of the per session one.

Signed-off-by: Mike Christie 
Link: https://lore.kernel.org/r/20230319015620.96006-5-michael.christie@oracle.com
Signed-off-by: Martin K. Petersen

scsi: target: Pass in cmd counter to use during cmd setup

2023-03-24T21:32:23+00:00

Allow target_get_sess_cmd() users to pass in the cmd counter they want to
use. Right now we pass in the session's cmd counter but in a subsequent
commit iSCSI will switch from per session to per conn.

Signed-off-by: Mike Christie 
Link: https://lore.kernel.org/r/20230319015620.96006-4-michael.christie@oracle.com
Signed-off-by: Martin K. Petersen

scsi: target: Move cmd counter allocation

2023-03-24T21:32:23+00:00

iSCSI needs to allocate its cmd counter per connection for MCS support
where we need to stop and wait on commands running on a connection instead
of per session. This moves the cmd counter allocation to
target_setup_session() which is used by drivers that need the stop+wait
behavior per session.

xcopy doesn't need stop+wait at all, so we will be OK moving the cmd
counter allocation outside of transport_init_session().

Signed-off-by: Mike Christie 
Link: https://lore.kernel.org/r/20230319015620.96006-3-michael.christie@oracle.com
Signed-off-by: Martin K. Petersen

scsi: target: Move sess cmd counter to new struct

2023-03-24T21:32:22+00:00

iSCSI needs to wait on outstanding commands like how SRP and the FC/FCoE
drivers do. It can't use target_stop_session() because for MCS support we
can't stop the entire session during recovery because if other connections
are OK then we want to be able to continue to execute I/O on them.

Move the per session cmd counters to a new struct so iSCSI can allocate
them per connection. The xcopy code can also just not allocate in the
future since it doesn't need to track commands.

Signed-off-by: Mike Christie 
Link: https://lore.kernel.org/r/20230319015620.96006-2-michael.christie@oracle.com
Reviewed-by: Maurizio Lombardi 
Signed-off-by: Martin K. Petersen

scsi: target: core: Add RTPI attribute for target port

2023-03-10T02:29:23+00:00

RELATIVE TARGET PORT IDENTIFIER can be read and configured via configfs:

$ echo 0x10 > $TARGET/tpgt_N/rtpi

RTPI can be changed only on disabled target ports.

Co-developed-by: Roman Bolshakov 
Signed-off-by: Roman Bolshakov 
Signed-off-by: Dmitry Bogdanov 
Link: https://lore.kernel.org/r/20230301084512.21956-5-d.bogdanov@yadro.com
Reviewed-by: Mike Christie 
Signed-off-by: Martin K. Petersen

scsi: target: core: Drop device-based RTPI

2023-03-10T02:29:23+00:00

The code is not needed since target port-based RTPI allocation replaced it.

Reviewed-by: Christoph Hellwig 
Signed-off-by: Roman Bolshakov 
Signed-off-by: Dmitry Bogdanov 
Link: https://lore.kernel.org/r/20230301084512.21956-4-d.bogdanov@yadro.com
Reviewed-by: Mike Christie 
Signed-off-by: Martin K. Petersen

scsi: target: core: Add RTPI field to target port

2023-03-10T02:29:23+00:00

SAM-5 4.6.5.2 (Relative Port Identifier attribute) defines the attribute as
unique across SCSI target ports.

The change introduces RTPI attribute to se_portal group. The value is
unique across all enabled SCSI target ports. It also limits number of SCSI
target ports to 65535.

Signed-off-by: Dmitry Bogdanov 
Link: https://lore.kernel.org/r/20230301084512.21956-2-d.bogdanov@yadro.com
Reviewed-by: Mike Christie 
Signed-off-by: Martin K. Petersen

scsi: target: core: Send max transfer length in blocks

2022-11-24T02:16:19+00:00

A MAXIMUM TRANSFER LENGTH value indicates the maximum transfer length in
logical blocks that the device server accepts for a single command. Fix
function sending the length in sectors instead of blocks.

This patch also removes the special casing for fileio in block_size_store
since this logic in now unified in spc_emulate_evpd_b0() for all backends.

Reviewed-by: Konstantin Shelekhin 
Reviewed-by: Dmitriy Bogdanov 
Signed-off-by: Anastasia Kovaleva 
Link: https://lore.kernel.org/r/20221114102500.88892-2-a.kovaleva@yadro.com
Reviewed-by: Mike Christie 
Signed-off-by: Martin K. Petersen