Add a LIO storage engine that presents commands to userspace for execution.
This would allow more complex backstores to be implemented out-of-kernel,
and also make experimentation a-la FUSE (but at the SCSI level -- "SUSE"?)
possible.
It uses a mmap()able UIO device per LUN to share a command ring and data
area. The commands are raw SCSI CDBs and iovs for in/out data. The command
ring is also reused for returning scsi command status and optional sense
data.
This implementation is based on Shaohua Li's earlier version but heavily
modified. Differences include:
* Shared memory allocated by kernel, not locked-down user pages
* Single ring for command request and response
* Offsets instead of embedded pointers
* Generic SCSI CDB passthrough instead of per-cmd specialization in ring
format.
* Uses UIO device instead of anon_file passed in mailbox.
* Optional in-kernel handling of some commands.
The main reason for these differences is to permit greater resiliency
if the user process dies or hangs.
Things not yet implemented (on purpose):
* Zero copy. The data area is flexible enough to allow page flipping or
backend-allocated pages to be used by fabrics, but it's not clear these
are performance wins. Can come later.
* Out-of-order command completion by userspace. Possible to add by just
allowing userspace to change cmd_id in rsp cmd entries, but currently
not supported.
* No locks between kernel cmd submission and completion routines. Sounds
like it's possible, but this can come later.
* Sparse allocation of mmaped area. Current code vmallocs the whole thing.
If the mapped area was larger and not fully mapped then the driver would
have more freedom to change cmd and data area sizes based on demand.
Current code open issues:
* The use of idrs may be overkill -- we maybe can replace them with a
simple counter to generate cmd_ids, and a hash table to get a cmd_id's
associated pointer.
* Use of a free-running counter for cmd ring instead of explicit modulo
math. This would require power-of-2 cmd ring size.
(Add kconfig depends NET - Randy)
Signed-off-by: Andy Grover <agrover@redhat.com>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
During temporary resource starvation at lower transport layer, command
is placed on queue full retry path, which expose this problem. The TCM
queue full handling of SCF_TRANSPORT_TASK_SENSE currently sends the same
cmd twice to lower layer. The 1st time led to cmd normal free path.
The 2nd time cause Null pointer access.
This regression bug was originally introduced v3.1-rc code in the
following commit:
commit e057f53308
Author: Christoph Hellwig <hch@infradead.org>
Date: Mon Oct 17 13:56:41 2011 -0400
target: remove the transport_qf_callback se_cmd callback
Signed-off-by: Quinn Tran <quinn.tran@qlogic.com>
Signed-off-by: Saurav Kashyap <saurav.kashyap@qlogic.com>
Cc: <stable@vger.kernel.org> # v3.1+
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
The target code has a rather generous helping of smp_mb__after_atomic()
throughout the code base. Most atomic operations were followed by one
and none were preceded by smp_mb__before_atomic(), nor accompanied by a
comment explaining the need for a barrier.
Instead of trying to prove for every case whether or not it is needed,
this patch introduces atomic_inc_mb() and atomic_dec_mb(), which
explicitly include the memory barriers before and after the atomic
operation. For now they are defined in a target header, although they
could be of general use.
Most of the existing atomic/mb combinations were replaced by the new
helpers. In a few cases the atomic was sandwiched in
spin_lock/spin_unlock and I simply removed the barrier.
I suspect that in most cases the correct conversion would have been to
drop the barrier. I also suspect that a few cases exist where a) the
barrier was necessary and b) a second barrier before the atomic would
have been necessary and got added by this patch.
Signed-off-by: Joern Engel <joern@logfs.org>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
atomic_inc_return() already does an implicit memory barrier and the
second case was moved from an atomic to a plain flag operation. If a
barrier were needed in the second case, it would have to be smp_mb(),
not a variant optimized away for x86 and other architectures.
Signed-off-by: Joern Engel <joern@logfs.org>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
Pull SCSI target updates from Nicholas Bellinger:
"The highlights this round include:
- Add support for T10 PI pass-through between vhost-scsi +
virtio-scsi (MST + Paolo + MKP + nab)
- Add support for T10 PI in qla2xxx target mode (Quinn + MKP + hch +
nab, merged through scsi.git)
- Add support for percpu-ida pre-allocation in qla2xxx target code
(Quinn + nab)
- A number of iser-target fixes related to hardening the network
portal shutdown path (Sagi + Slava)
- Fix response length residual handling for a number of control CDBs
(Roland + Christophe V.)
- Various iscsi RFC conformance fixes in the CHAP authentication path
(Tejas and Calsoft folks + nab)
- Return TASK_SET_FULL status for tcm_fc(FCoE) DataIn + Response
failures (Vasu + Jun + nab)
- Fix long-standing ABORT_TASK + session reset hang (nab)
- Convert iser-initiator + iser-target to include T10 bytes into EDTL
(Sagi + Or + MKP + Mike Christie)
- Fix NULL pointer dereference regression related to XCOPY introduced
in v3.15 + CC'ed to v3.12.y (nab)"
* 'for-next' of git://git.kernel.org/pub/scm/linux/kernel/git/nab/target-pending: (34 commits)
target: Fix NULL pointer dereference for XCOPY in target_put_sess_cmd
vhost-scsi: Include prot_bytes into expected data transfer length
TARGET/sbc,loopback: Adjust command data length in case pi exists on the wire
libiscsi, iser: Adjust data_length to include protection information
scsi_cmnd: Introduce scsi_transfer_length helper
target: Report correct response length for some commands
target/sbc: Check that the LBA and number of blocks are correct in VERIFY
target/sbc: Remove sbc_check_valid_sectors()
Target/iscsi: Fix sendtargets response pdu for iser transport
Target/iser: Fix a wrong dereference in case discovery session is over iser
iscsi-target: Fix ABORT_TASK + connection reset iscsi_queue_req memory leak
target: Use complete_all for se_cmd->t_transport_stop_comp
target: Set CMD_T_ACTIVE bit for Task Management Requests
target: cleanup some boolean tests
target/spc: Simplify INQUIRY EVPD=0x80
tcm_fc: Generate TASK_SET_FULL status for response failures
tcm_fc: Generate TASK_SET_FULL status for DataIN failures
iscsi-target: Reject mutual authentication with reflected CHAP_C
iscsi-target: Remove no-op from iscsit_tpg_del_portal_group
iscsi-target: Fix CHAP_A parameter list handling
...
This patch fixes a NULL pointer dereference regression bug that was
introduced with:
commit 1e1110c43b
Author: Mikulas Patocka <mpatocka@redhat.com>
Date: Sat May 17 06:49:22 2014 -0400
target: fix memory leak on XCOPY
Now that target_put_sess_cmd() -> kref_put_spinlock_irqsave() is
called with a valid se_cmd->cmd_kref, a NULL pointer dereference
is triggered because the XCOPY passthrough commands don't have
an associated se_session pointer.
To address this bug, go ahead and checking for a NULL se_sess pointer
within target_put_sess_cmd(), and call se_cmd->se_tfo->release_cmd()
to release the XCOPY's xcopy_pt_cmd memory.
Reported-by: Thomas Glanzmann <thomas@glanzmann.de>
Cc: Thomas Glanzmann <thomas@glanzmann.de>
Cc: Mikulas Patocka <mpatocka@redhat.com>
Cc: stable@vger.kernel.org # 3.12+
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
When an initiator sends an allocation length bigger than what its
command consumes, the target should only return the actual response data
and set the residual length to the unused part of the allocation length.
Add a helper function that command handlers (INQUIRY, READ CAPACITY,
etc) can use to do this correctly, and use this code to get the correct
residual for commands that don't use the full initiator allocation in the
handlers for READ CAPACITY, READ CAPACITY(16), INQUIRY, MODE SENSE and
REPORT LUNS.
This addresses a handful of failures as reported by Christophe with
the Windows Certification Kit:
http://permalink.gmane.org/gmane.linux.scsi.target.devel/6515
Signed-off-by: Roland Dreier <roland@purestorage.com>
Tested-by: Christophe Vu-Brugier <cvubrugier@yahoo.fr>
Cc: stable@vger.kernel.org # 3.10+
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
This patch fixes a bug where multiple waiters on ->t_transport_stop_comp
occurs due to a concurrent ABORT_TASK and session reset both invoking
transport_wait_for_tasks(), while waiting for the associated se_cmd
descriptor backend processing to complete.
For this case, complete_all() should be invoked in order to wake up
both waiters in core_tmr_abort_task() + transport_generic_free_cmd()
process contexts.
Cc: Thomas Glanzmann <thomas@glanzmann.de>
Cc: Charalampos Pournaris <charpour@gmail.com>
Cc: stable@vger.kernel.org # 3.10+
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
This patch fixes a bug where se_cmd descriptors associated with a
Task Management Request (TMR) where not setting CMD_T_ACTIVE before
being dispatched into target_tmr_work() process context.
This is required in order for transport_generic_free_cmd() ->
transport_wait_for_tasks() to wait on se_cmd->t_transport_stop_comp
if a session reset event occurs while an ABORT_TASK is outstanding
waiting for another I/O to complete.
Cc: Thomas Glanzmann <thomas@glanzmann.de>
Cc: Charalampos Pournaris <charpour@gmail.com>
Cc: stable@vger.kernel.org # 3.10+
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
Convert "x == true" to "x" and "x == false" to "!x".
Signed-off-by: Christophe Vu-Brugier <cvubrugier@yahoo.fr>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
On each processed XCOPY command, two "kmalloc-512" memory objects are
leaked. These represent two allocations of struct xcopy_pt_cmd in
target_core_xcopy.c.
The reason for the memory leak is that the cmd_kref field is not
initialized (thus, it is zero because the allocations were done with
kzalloc). When we decrement zero kref in target_put_sess_cmd, the result
is not zero, thus target_release_cmd_kref is not called.
This patch fixes the bug by moving kref initialization from
target_get_sess_cmd to transport_init_se_cmd (this function is called from
target_core_xcopy.c, so it will correctly initialize cmd_kref). It can be
easily verified that all code that calls target_get_sess_cmd also calls
transport_init_se_cmd earlier, thus moving kref_init shouldn't introduce
any new problems.
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Cc: stable@vger.kernel.org # 3.12+
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
This patch enables the use of READ_STRIP software emulation in
target_complete_ok_work() code for I/O READs.
This is useful when the fabric does not support READ_STRIP hardware
offload, but would still like to interact with backend device
that have T10 PI enabled.
v2 changes:
- Move TARGET_PROT_DIN_STRIP check from target_check_read_strip()
into target_complete_ok_work() (Sagi)
Cc: Martin K. Petersen <martin.petersen@oracle.com>
Cc: Sagi Grimberg <sagig@mellanox.com>
Cc: Or Gerlitz <ogerlitz@mellanox.com>
Cc: Quinn Tran <quinn.tran@qlogic.com>
Cc: Giridhar Malavali <giridhar.malavali@qlogic.com>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
This patch enables WRITE_INSERT emulation in target_execute_cmd()
in order to locally generate DIF PI before submitting the WRITE
to the underlying backend device.
This is required for fabric drivers that currently don't support
DIF over-the-wire, in order to inact with backend devices that
have hardware (IBLOCK) or software (FILEIO + RAMDISK) support
for handling T10 PI.
v2 changes:
- Convert to sbc_dif_generate() usage (Sagi)
Reviewed-by: Sagi Grimberg <sagig@mellanox.com>
Cc: Martin K. Petersen <martin.petersen@oracle.com>
Cc: Or Gerlitz <ogerlitz@mellanox.com>
Cc: Quinn Tran <quinn.tran@qlogic.com>
Cc: Giridhar Malavali <giridhar.malavali@qlogic.com>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
In order to support local WRITE_INSERT + READ_STRIP operations for
non PI enabled fabrics, the fabric driver needs to be able signal
what protection offload operations are supported.
This is done at session initialization time so the modes can be
signaled by individual se_wwn + se_portal_group endpoints, as well
as optionally across different transports on the same endpoint.
For iser-target, set TARGET_PROT_ALL if the underlying ib_device
has already signaled PI offload support, and allow this to be
exposed via a new iscsit_transport->iscsit_get_sup_prot_ops()
callback.
For loopback, set TARGET_PROT_ALL to signal SCSI initiator mode
operation.
For all other drivers, set TARGET_PROT_NORMAL to disable fabric
level PI.
Cc: Martin K. Petersen <martin.petersen@oracle.com>
Cc: Sagi Grimberg <sagig@mellanox.com>
Cc: Or Gerlitz <ogerlitz@mellanox.com>
Cc: Quinn Tran <quinn.tran@qlogic.com>
Cc: Giridhar Malavali <giridhar.malavali@qlogic.com>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
Now that TASK_ABORTED status is not generated for all cases by
TMR ABORT_TASK + LUN_RESET, a new TFO->abort_task() caller is
necessary in order to give fabric drivers a chance to unmap
hardware / software resources before the se_cmd descriptor is
released via the normal TFO->release_cmd() codepath.
This patch adds TFO->aborted_task() in core_tmr_abort_task()
in place of the original transport_send_task_abort(), and
also updates all fabric drivers to implement this caller.
The fabric drivers that include changes to perform cleanup
via ->aborted_task() are:
- iscsi-target
- iser-target
- srpt
- tcm_qla2xxx
The fabric drivers that currently set ->aborted_task() to
NOPs are:
- loopback
- tcm_fc
- usb-gadget
- sbp-target
- vhost-scsi
For the latter five, there appears to be no additional cleanup
required before invoking TFO->release_cmd() to release the
se_cmd descriptor.
v2 changes:
- Move ->aborted_task() call into transport_cmd_finish_abort (Alex)
Cc: Alex Leung <amleung21@yahoo.com>
Cc: Mark Rustad <mark.d.rustad@intel.com>
Cc: Roland Dreier <roland@kernel.org>
Cc: Vu Pham <vu@mellanox.com>
Cc: Chris Boot <bootc@bootc.net>
Cc: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Cc: Michael S. Tsirkin <mst@redhat.com>
Cc: Giridhar Malavali <giridhar.malavali@qlogic.com>
Cc: Saurav Kashyap <saurav.kashyap@qlogic.com>
Cc: Quinn Tran <quinn.tran@qlogic.com>
Cc: Sagi Grimberg <sagig@mellanox.com>
Cc: Or Gerlitz <ogerlitz@mellanox.com>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
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>
Some transports (iSCSI/iSER/SRP/FC) support hardware INSERT/STRIP
capabilities while other transports like loopback/vhost-scsi need
perform this is software.
This patch allows fabrics using SCF_PASSTHROUGH_SG_TO_MEM_NOALLOC
to signal the early LUN scan handling case where PROTECT CDB bits
are set, but no fabric buffer has been provided.
For transports which use generic new command these buffers have yet
to be allocated.
Also this way, target may support protection information
against legacy initiators (writes are inserted and reads
are stripped).
(Only set prot_pto for loopback during early special case - nab)
Signed-off-by: Sagi Grimberg <sagig@mellanox.com>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
SBC-3 mandates the protection checks that must be
performed in the rdprotect/wrprotect field. Use them.
According to backstore device pi_attributes and
cdb rdprotect/wrprotect field.
(Fix incorrect se_cmd->prot_type -> TARGET_PROT_NORMAL
comparision in transport_generic_new_cmd - nab)
(Fix missing break in sbc_set_prot_op_checks - DanC + Sagi)
Signed-off-by: Sagi Grimberg <sagig@mellanox.com>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
In case protection information is involved, allocate
protection SG-list for transport.
Signed-off-by: Sagi Grimberg <sagig@mellanox.com>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
This patch adds the three missing DIF related sense codes within
transport_generic_request_failure(), which are required to ensure
that the correct ASC/ASQC is generated by the subsequent call to
transport_send_check_condition_and_sense().
Cc: Martin K. Petersen <martin.petersen@oracle.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Hannes Reinecke <hare@suse.de>
Cc: Sagi Grimberg <sagig@mellanox.com>
Cc: Or Gerlitz <ogerlitz@mellanox.com>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
The CMD_T_FAILED flag is set used in one place to record the result of a
trivial test, and it is only tested once, few lines later. We might as
well make the code simpler and easier to read by directly doing the test
of "success" where we want to use it.
Signed-off-by: Roland Dreier <roland@purestorage.com>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
This patch fixes a percpu_ref_put race for se_lun->lun_ref in
transport_lun_remove_cmd() where ->lun_ref could end up being
put more than once per command via different target completion
and fabric release contexts.
It adds a cmpxchg() for se_cmd->lun_ref_active to ensure that
percpu_ref_put() is only ever called once per se_cmd.
This bug was manifesting itself as a LUN shutdown regression
bug in >= v3.13 code, where percpu_ref_kill() would end up
hanging indefinately due to the incorrect percpu_ref count.
(Change se_cmd->lun_ref_active from bool -> int to force at
least a 4-byte cmpxchg with MIPS ll/sc ins. - Fengguang)
Reported-by: Tommy Apel <tommyapeldk@gmail.com>
Cc: Tommy Apel <tommyapeldk@gmail.com>
Cc: <stable@vger.kernel.org> #3.13+
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
SPC-4 states that data-integrity errors shall also report
the failed sector in CHECK_CONDITION response sense data
information field.
Signed-off-by: Sagi Grimberg <sagig@mellanox.com>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
This patch adds support to target_submit_cmd_map_sgls() for
accepting 'sgl_prot' + 'sgl_prot_count' parameters for
DIF protection information.
Note the passed parameters are stored at se_cmd->t_prot_sg
and se_cmd->t_prot_nents respectively.
Also, update tcm_loop and vhost-scsi fabrics usage of
target_submit_cmd_map_sgls() to take into account the
new parameters.
Cc: Martin K. Petersen <martin.petersen@oracle.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Hannes Reinecke <hare@suse.de>
Cc: Sagi Grimberg <sagig@mellanox.com>
Cc: Or Gerlitz <ogerlitz@mellanox.com>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
This patch adds support for DIF related CHECK_CONDITION ASC/ASCQ
exception cases into transport_send_check_condition_and_sense().
This includes:
LOGICAL BLOCK GUARD CHECK FAILED
LOGICAL BLOCK APPLICATION TAG CHECK FAILED
LOGICAL BLOCK REFERENCE TAG CHECK FAILED
that used by DIF TYPE1 and TYPE3 failure cases.
Cc: Martin K. Petersen <martin.petersen@oracle.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Hannes Reinecke <hare@suse.de>
Cc: Sagi Grimberg <sagig@mellanox.com>
Cc: Or Gerlitz <ogerlitz@mellanox.com>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
Referrals need an LBA map, which needs to be kept
consistent across all target port groups. So
instead of tying the map to the target port groups
I've implemented a single attribute containing the
entire map.
Signed-off-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
Pull SCSI target updates from Nicholas Bellinger:
"Things have been quiet this round with mostly bugfixes, percpu
conversions, and other minor iscsi-target conformance testing changes.
The highlights include:
- Add demo_mode_discovery attribute for iscsi-target (Thomas)
- Convert tcm_fc(FCoE) to use percpu-ida pre-allocation
- Add send completion interrupt coalescing for ib_isert
- Convert target-core to use percpu-refcounting for se_lun
- Fix mutex_trylock usage bug in iscsit_increment_maxcmdsn
- tcm_loop updates (Hannes)
- target-core ALUA cleanups + prep for v3.14 SCSI Referrals support (Hannes)
v3.14 is currently shaping to be a busy development cycle in target
land, with initial support for T10 Referrals and T10 DIF currently on
the roadmap"
* 'for-next' of git://git.kernel.org/pub/scm/linux/kernel/git/nab/target-pending: (40 commits)
iscsi-target: chap auth shouldn't match username with trailing garbage
iscsi-target: fix extract_param to handle buffer length corner case
iscsi-target: Expose default_erl as TPG attribute
target_core_configfs: split up ALUA supported states
target_core_alua: Make supported states configurable
target_core_alua: Store supported ALUA states
target_core_alua: Rename ALUA_ACCESS_STATE_OPTIMIZED
target_core_alua: spellcheck
target core: rename (ex,im)plict -> (ex,im)plicit
percpu-refcount: Add percpu-refcount.o to obj-y
iscsi-target: Do not reject non-immediate CmdSNs exceeding MaxCmdSN
iscsi-target: Convert iscsi_session statistics to atomic_long_t
target: Convert se_device statistics to atomic_long_t
target: Fix delayed Task Aborted Status (TAS) handling bug
iscsi-target: Reject unsupported multi PDU text command sequence
ib_isert: Avoid duplicate iscsit_increment_maxcmdsn call
iscsi-target: Fix mutex_trylock usage in iscsit_increment_maxcmdsn
target: Core does not need blkdev.h
target: Pass through I/O topology for block backstores
iser-target: Avoid using FRMR for single dma entry requests
...
This patch fixes a bug in delayed Task Aborted Status (TAS) handling,
where transport_send_task_abort() was not returning for the case
when the se_tfo->write_pending() callback indicated that last fabric
specific WRITE PDU had not yet been received.
It also adds an explicit cmd->scsi_status = SAM_STAT_TASK_ABORTED
assignment within transport_check_aborted_status() to avoid the case
where se_tfo->queue_status() is called when the SAM_STAT_TASK_ABORTED
assignment + ->queue_status() in transport_send_task_abort() does not
occur once SCF_SENT_DELAYED_TAS has been set.
Cc: <stable@vger.kernel.org> #3.2+
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
Target core does not depend on the block layer, only backstores that
use the block layer do.
Signed-off-by: Andy Grover <agrover@redhat.com>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
Now with percpu refcounting for se_lun in place, go ahead and drop
the legacy per se_cmd accounting for se_lun shutdown.
This includes __transport_clear_lun_from_sessions(), the associated
transport_lun_wait_for_tasks() logic, along with a handful of now
unused se_cmd structure members and ->transport_state bits.
Cc: Kent Overstreet <kmo@daterainc.com>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
This patch adds percpu refcounting for se_lun access that allows the
association of an se_lun + se_cmd in transport_lookup_cmd_lun() to
occur without an extra list_head for tracking outstanding I/O during
se_lun shutdown.
This effectively changes se_lun shutdown logic to wait for outstanding
I/O percpu references to complete in transport_lun_remove_cmd() using
se_lun->lun_ref_comp, instead of explicitly draining the per se_lun
command list and waiting for individual se_cmd descriptor processing
to complete.
Cc: Kent Overstreet <kmo@daterainc.com>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
This patch changes transport_alloc_session_tags() to fall back to
use vzalloc when kzalloc fails for big tag_num that end up generating
larger order allocations.
Also use is_vmalloc_addr() in transport_alloc_session_tags() failure
path, and normal transport_free_session() path to determine when
vfree() needs to be called instead of kfree().
v2 changes:
- Use __GFP_NOWARN | __GFP_REPEAT for sess_cmd_map kzalloc (mst)
Cc: Michael S. Tsirkin <mst@redhat.com>
Cc: Asias He <asias@redhat.com>
Cc: Kent Overstreet <kmo@daterainc.com>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
Pull SCSI target updates from Nicholas Bellinger:
"Lots of activity again this round for I/O performance optimizations
(per-cpu IDA pre-allocation for vhost + iscsi/target), and the
addition of new fabric independent features to target-core
(COMPARE_AND_WRITE + EXTENDED_COPY).
The main highlights include:
- Support for iscsi-target login multiplexing across individual
network portals
- Generic Per-cpu IDA logic (kent + akpm + clameter)
- Conversion of vhost to use per-cpu IDA pre-allocation for
descriptors, SGLs and userspace page pointer list
- Conversion of iscsi-target + iser-target to use per-cpu IDA
pre-allocation for descriptors
- Add support for generic COMPARE_AND_WRITE (AtomicTestandSet)
emulation for virtual backend drivers
- Add support for generic EXTENDED_COPY (CopyOffload) emulation for
virtual backend drivers.
- Add support for fast memory registration mode to iser-target (Vu)
The patches to add COMPARE_AND_WRITE and EXTENDED_COPY support are of
particular significance, which make us the first and only open source
target to support the full set of VAAI primitives.
Currently Linux clients are lacking upstream support to actually
utilize these primitives. However, with server side support now in
place for folks like MKP + ZAB working on the client, this logic once
reserved for the highest end of storage arrays, can now be run in VMs
on their laptops"
* 'for-next' of git://git.kernel.org/pub/scm/linux/kernel/git/nab/target-pending: (50 commits)
target/iscsi: Bump versions to v4.1.0
target: Update copyright ownership/year information to 2013
iscsi-target: Bump default TCP listen backlog to 256
target: Fix >= v3.9+ regression in PR APTPL + ALUA metadata write-out
iscsi-target; Bump default CmdSN Depth to 64
iscsi-target: Remove unnecessary wait_for_completion in iscsi_get_thread_set
iscsi-target: Add thread_set->ts_activate_sem + use common deallocate
iscsi-target: Fix race with thread_pre_handler flush_signals + ISCSI_THREAD_SET_DIE
target: remove unused including <linux/version.h>
iser-target: introduce fast memory registration mode (FRWR)
iser-target: generalize rdma memory registration and cleanup
iser-target: move rdma wr processing to a shared function
target: Enable global EXTENDED_COPY setup/release
target: Add Third Party Copy (3PC) bit in INQUIRY response
target: Enable EXTENDED_COPY setup in spc_parse_cdb
target: Add support for EXTENDED_COPY copy offload emulation
target: Avoid non-existent tg_pt_gp_mem in target_alua_state_check
target: Add global device list for EXTENDED_COPY
target: Make helpers non static for EXTENDED_COPY command setup
target: Make spc_parse_naa_6h_vendor_specific non static
...
Update copyright ownership/year information for target-core,
loopback, iscsi-target, tcm_qla2xx, vhost and iser-target.
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
Both target_alloc_sgl() and transport_generic_map_mem_to_cmd() are
required by EXTENDED_COPY logic when setting up internally dispatched
command descriptors, so go ahead and make both of these non static.
Cc: Christoph Hellwig <hch@lst.de>
Cc: Hannes Reinecke <hare@suse.de>
Cc: Martin Petersen <martin.petersen@oracle.com>
Cc: Chris Mason <chris.mason@fusionio.com>
Cc: Roland Dreier <roland@purestorage.com>
Cc: Zach Brown <zab@redhat.com>
Cc: James Bottomley <JBottomley@Parallels.com>
Cc: Nicholas Bellinger <nab@linux-iscsi.org>
Signed-off-by: Nicholas Bellinger <nab@daterainc.com>
This patch adds a extra check for SCF_COMPARE_AND_WRITE within
transport_generic_request_failure() to invoke the callback for
compare_and_write_callback() or compare_and_write_done(), in
order to release se_dev->caw_mutex from the generic failure
path.
It also adds to checks within compare_and_write_callback() to
avoid processing when transport_generic_request_failure() occurs
early enough that cmd->t_data_sg or cmd->t_bidi_data_sg have not
been setup yet, nor se_dev->caw_mutex obtained from within
sbc_compare_and_write().
v4 changes:
- Add explicit check for cmd->transport_complete_callback in
transport_generic_request_failure() to handle case where
sbc_compare_and_write()clears callback pointer (Dan Carpenter)
Cc: Christoph Hellwig <hch@lst.de>
Cc: Hannes Reinecke <hare@suse.de>
Cc: Martin Petersen <martin.petersen@oracle.com>
Cc: Chris Mason <chris.mason@fusionio.com>
Cc: James Bottomley <JBottomley@Parallels.com>
Cc: Nicholas Bellinger <nab@linux-iscsi.org>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
This patch changes target_complete_ok_work() to fall through
after calling the se_cmd->transport_complete_callback() ->
compare_and_write_post() callback, by keying off the existance
of SCF_COMPARE_AND_WRITE_POST.
This is necessary because once SCF_COMPARE_AND_WRITE_POST has
been set by compare_and_write_post(), the SCSI response needs
to be sent via TFO->queue_status().
Cc: Christoph Hellwig <hch@lst.de>
Cc: Hannes Reinecke <hare@suse.de>
Cc: Martin Petersen <martin.petersen@oracle.com>
Cc: Chris Mason <chris.mason@fusionio.com>
Cc: James Bottomley <JBottomley@Parallels.com>
Cc: Nicholas Bellinger <nab@linux-iscsi.org>
Signed-off-by: Nicholas Bellinger <nab@daterainc.com>
Required by COMPARE_AND_WRITE for write instance user-data
submission, in order to bypass target_execute_cmd() checks.
Reported-by: Christoph Hellwig <hch@lst.de>
Cc: Roland Dreier <roland@purestorage.com>
Cc: Nicholas Bellinger <nab@linux-iscsi.org>
Signed-off-by: Nicholas Bellinger <nab@daterainc.com>
After COMPARE_AND_WRITE completes it's comparision, the WRITE
payload SGLs head expect to be updated to point from the verify
instance of user data, to the write instance of user data.
So for this special case, add transport_reset_sgl_orig() usage
within transport_free_pages() and add se_cmd->t_data_[sg,nents]_orig
members to save the original assignments.
Cc: Christoph Hellwig <hch@lst.de>
Cc: Hannes Reinecke <hare@suse.de>
Cc: Martin Petersen <martin.petersen@oracle.com>
Cc: Chris Mason <chris.mason@fusionio.com>
Cc: James Bottomley <JBottomley@Parallels.com>
Cc: Nicholas Bellinger <nab@linux-iscsi.org>
Signed-off-by: Nicholas Bellinger <nab@daterainc.com>
This patch updates transport_generic_new_cmd() to call target_alloc_sgl()
for SGL + page memory allocation for se_cmd->t_bidi_data_sg.
It also adds the special case for SCF_COMPARE_AND_WRITE to calculate a
different bidi_length based upon se_cmd->t_task_nolb.
Reported-by: Christoph Hellwig <hch@lst.de>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Hannes Reinecke <hare@suse.de>
Cc: Martin Petersen <martin.petersen@oracle.com>
Cc: Chris Mason <chris.mason@fusionio.com>
Cc: James Bottomley <JBottomley@Parallels.com>
Cc: Nicholas Bellinger <nab@linux-iscsi.org>
Signed-off-by: Nicholas Bellinger <nab@daterainc.com>
This patch refactors transport_generic_get_mem() to target_alloc_sgl()
for accepting **sgl, *nents, length and zero_page as function parameters
in order to be used for both se_cmd->t_data_sg + se_cmd->t_bidi_data_sg
allocations.
Reported-by: Christoph Hellwig <hch@lst.de>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Hannes Reinecke <hare@suse.de>
Cc: Martin Petersen <martin.petersen@oracle.com>
Cc: Chris Mason <chris.mason@fusionio.com>
Cc: James Bottomley <JBottomley@Parallels.com>
Cc: Nicholas Bellinger <nab@linux-iscsi.org>
Signed-off-by: Nicholas Bellinger <nab@daterainc.com>
Stop keying off se_cmd->t_bidi_data_sg within transport_complete_qf()
+ target_complete_ok_work(), and just use SCF_BIDI instead.
Cc: Christoph Hellwig <hch@lst.de>
Cc: Hannes Reinecke <hare@suse.de>
Cc: Martin Petersen <martin.petersen@oracle.com>
Cc: Chris Mason <chris.mason@fusionio.com>
Cc: James Bottomley <JBottomley@Parallels.com>
Cc: Nicholas Bellinger <nab@linux-iscsi.org>
Signed-off-by: Nicholas Bellinger <nab@daterainc.com>
This patch adds TCM_MISCOMPARE_VERIFY (ASC=0x1d, ASCQ=0x00) sense
handling to transport_send_check_condition_and_sense(), which is
required for a COMPARE_AND_WRITE comparision failure.
Cc: Christoph Hellwig <hch@lst.de>
Cc: Hannes Reinecke <hare@suse.de>
Cc: Martin Petersen <martin.petersen@oracle.com>
Cc: Chris Mason <chris.mason@fusionio.com>
Cc: James Bottomley <JBottomley@Parallels.com>
Cc: Nicholas Bellinger <nab@linux-iscsi.org>
Signed-off-by: Nicholas Bellinger <nab@daterainc.com>
This patch adds a sense_reason_t return to ->transport_complete_callback(),
and updates target_complete_ok_work() to invoke the call if necessary to
transport_send_check_condition_and_sense() during the failure case.
Also update xdreadwrite_callback() to use this return value.
Cc: Christoph Hellwig <hch@lst.de>
Cc: Hannes Reinecke <hare@suse.de>
Cc: Martin Petersen <martin.petersen@oracle.com>
Cc: Chris Mason <chris.mason@fusionio.com>
Cc: James Bottomley <JBottomley@Parallels.com>
Cc: Nicholas Bellinger <nab@linux-iscsi.org>
Signed-off-by: Nicholas Bellinger <nab@daterainc.com>
This patch adds lib/idr.c based transport_init_session_tags() logic
that allows fabric drivers to setup a per-cpu se_sess->sess_tag_pool
and associated se_sess->sess_cmd_map for basic tagged pre-allocation
of fabric descriptor sized memory.
v5 changes:
- Convert to percpu_ida.h include
v4 changes:
- Add transport_alloc_session_tags() for fabrics that need early
transport_init_session()
v3 changes:
- Update to percpu-ida usage
Cc: Kent Overstreet <kmo@daterainc.com>
Cc: Asias He <asias@redhat.com>
Cc: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Asias He <asias@redhat.com>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
This patch addresses a v3.11 specific regression where se_cmd->state_list
was being leaked during a fabric WRITE failure, when the fabric releases
an associated se_cmd descriptor before I/O submission occurs, and normal
fast path callbacks have a chance to call target_remove_from_state_list().
It was manifesting with Poison overwritten messages with iscsi-target
once an ImmediateData payload CRC32C failure occured.
This bug was originally introduced during v3.11-rc1 with the following
commit:
commit 0b66818ac6
Author: Nicholas Bellinger <nab@linux-iscsi.org>
Date: Thu Jun 6 01:36:41 2013 -0700
target: Drop unnecessary CMD_T_DEV_ACTIVE check from transport_lun_remove_cmd
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
This patch adds tracepoints to the target code for commands being
received and being completed, which is quite useful for debugging
interactions with initiators. For example, one can do something like the
following to watch commands that are completing unsuccessfully:
# echo 'scsi_status!=0' > /sys/kernel/debug/tracing/events/target/target_cmd_complete/filter
# echo 1 > /sys/kernel/debug/tracing/events/target/target_cmd_complete/enable
<run command that fails>
# cat /sys/kernel/debug/tracing/trace
iscsi_trx-0-1902 [003] ...1 990185.810385: target_cmd_complete: iqn.1993-08.org.debian:01:e51ede6aacfd <- LUN 001 status CHECK CONDITION (sense len 18 / 70 00 05 00 00 00 00 0a 00 00 00 00 20 00 00 00 00 00) 0x95 data_length 512 CDB 95 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 (TA:SIMPLE C:00)
(v2: Drop undefined COMPARE_AND_WRITE)
Signed-off-by: Roland Dreier <roland@purestorage.com>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
Andy Grover