Fabric drivers currently expect to internally release se_cmd in the event
of a TMR failure during target_submit_tmr(), which means the immediate call
to transport_generic_free_cmd() after TFO->queue_tm_rsp() from within
target_complete_tmr_failure() workqueue context is wrong.
This is done as some fabrics expect TMR operations to be acknowledged
before releasing the descriptor, so the assumption that core is releasing
se_cmd associated TMR memory is incorrect. This fixes a OOPs where
transport_generic_free_cmd() was being called more than once.
This bug was originally observed with tcm_qla2xxx fabric ports.
Cc: Christoph Hellwig <hch@lst.de>
Cc: Roland Dreier <roland@purestorage.com>
Cc: Andy Grover <agrover@redhat.com>
Cc: stable@vger.kernel.org
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
This patch carries forward a work-around from tcm_loop to target
core code to explicitly clear control CDB READ paylods in order to
avoid bugs in scsi-generic user-space code for INQUIRY that do not
explicitly zero CDB payload memory.
(v2: Drop TARGET_SCF_MAP_CLEAR_MEM, and perform the explicit zero
of READ memory for all target_submit_cmd_map_sgls users)
Cc: Christoph Hellwig <hch@lst.de>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
This patch adds a new target_submit_cmd_map_sgls() to pass pre-allocated
SGL memory using transport_generic_map_mem_to_cmd() logic into the generic
target submit I/O codepath.
It also adds a target_submit_cmd() wrapper around target_submit_cmd_map_sgls()
for existing fabric code that already assumes internal target-core SGL memory
allocation.
(v2: Rename to target_submit_cmd_map_sgls + drop TARGET_SCF_MAP_MEM flag
in favor of non zero sgl_count check)
Reported-by: Christoph Hellwig <hch@lst.de>
Cc: Christoph Hellwig <hch@lst.de>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
Yay, all users of transport_kmap_data_sg now check for a zero-length
request and/or a too-small parameter list length. We can thus go through
the normal emulation path even for such commands.
This means that out-of-bounds reads and writes are now reported correctly
even if they transfer 0 blocks. Other errors are also reported correctly.
Testcase: sg_raw /dev/sdb 28 00 80 00 00 00 00 00 00 00
should fail with ILLEGAL REQUEST / LBA OUT OF RANGE sense
does not fail without the patch
(still wrong with the patch, but better: the ASC is INVALID FIELD IN CDB)
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
Correct spelling typo in printk and comment within drivers/target.
Signed-off-by: Masanari Iida <standby24x7@gmail.com>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
Every fabric driver has to supply a se_tfo->set_fabric_sense_len()
method, just so iSCSI can return an offset of 2. However, every fabric
driver is already allocating a sense buffer and passing it into the
target core, either via transport_init_se_cmd() or target_submit_cmd().
So instead of having iSCSI pass the start of its sense buffer into the
core and then later tell the core to skip the first 2 bytes, it seems
easier for iSCSI just to do the offset of 2 when it passes the sense
buffer into the core. Then we can drop the se_tfo->set_fabric_sense_len()
everywhere, and just add a couple of lines of code to iSCSI to set the
sense data length to the beginning of the buffer right before it sends
it over the network.
(nab: Remove .set_fabric_sense_len usage from tcm_qla2xxx_npiv_ops +
change transport_get_sense_buffer to follow v3.6-rc6 code w/o
->set_fabric_sense_len usage)
Signed-off-by: Roland Dreier <roland@purestorage.com>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
Move static into function body from file scope.
Remove extraneous return statement
Signed-off-by: Andy Grover <agrover@redhat.com>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
Now that spc_emulate_request_sense has been taught to process zero-length
REQUEST SENSE correctly, drop the special handling of unit attention
conditions from transport_generic_new_cmd. However, for now REQUEST SENSE
will be the only command that goes through emulation for zero lengths.
(nab: Fix up zero-length check in transport_generic_new_cmd)
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
In order to support zero-size allocation lengths, do not assert
that we have a scatterlist until after checking cmd->data_length.
But once we do this, we can have two cases of transport_kmap_data_sg
returning NULL: a zero-size allocation length, or an out-of-memory
condition. Report the latter using sense codes, so that the SCSI
command that triggered it will fail.
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
Right now, commands with a zero-size payload are skipped completely.
This is wrong; such commands should be passed down to the device and
processed normally.
For physical backends, this ignores completely things such as START
STOP UNIT. For virtual backends, we have a hack in place to clear a
unit attention state on a zero-size REQUEST SENSE, but we still do
not report errors properly on zero-length commands---out-of-bounds
0-block reads and writes, too small parameter list lengths, etc.
This patch fixes this for PSCSI. Uses of transport_kmap_data_sg are
guarded with a check for non-zero cmd->data_length; for all other
commands a zero length is handled properly in pscsi_execute_cmd.
The sole exception will be for now REPORT LUNS, which is handled
through the normal SPC emulation.
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
The pointer to the sense buffer is fetched by transport_get_sense_data,
but this is called by target_complete_ok_work long after pscsi_req_done
has freed the struct that contains it.
Pass instead the fabric's sense buffer to transport_complete,
and copy the data to it directly in transport_complete. Setting
SCF_TRANSPORT_TASK_SENSE also becomes a duty of transport_complete.
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Cc: stable@vger.kernel.org
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
The error conditions in transport_get_sense_data are superfluous
and complicate the code unnecessarily:
* SCF_TRANSPORT_TASK_SENSE is checked in the caller;
* it's simply part of the invariants of dev->transport->get_sense_buffer
that it must be there if transport_complete ever returns 1, and that
it must not return NULL. Besides, the entire callback will disappear
with the next patch.
* similarly in the caller we can expect that sense data is only sent
for non-zero cmd->scsi_status.
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Cc: stable@vger.kernel.org
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
We will be calling it from transport_complete_cmd, avoid forward
declarations. No semantic change.
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Cc: stable@vger.kernel.org
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
This patch fixes a long-standing bug with SCSI overflow handling
where se_cmd->data_length was incorrectly being re-assigned to
the larger CDB extracted allocation length, resulting in a number
of fabric level errors that would end up causing a session reset
in most cases. So instead now:
- Only re-assign se_cmd->data_length durining UNDERFLOW (to use the
smaller value)
- Use existing se_cmd->data_length for OVERFLOW (to use the smaller
value)
This fix has been tested with the following CDB to generate an
SCSI overflow:
sg_raw -r512 /dev/sdc 28 0 0 0 0 0 0 0 9 0
Tested using iscsi-target, tcm_qla2xxx, loopback and tcm_vhost fabric
ports. Here is a bit more detail on each case:
- iscsi-target: Bug with open-iscsi with overflow, sg_raw returns
-3584 bytes of data.
- tcm_qla2xxx: Working as expected, returnins 512 bytes of data
- loopback: sg_raw returns CHECK_CONDITION, from overflow rejection
in transport_generic_map_mem_to_cmd()
- tcm_vhost: Same as loopback
Reported-by: Roland Dreier <roland@purestorage.com>
Cc: Roland Dreier <roland@purestorage.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Boaz Harrosh <bharrosh@panasas.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
This was originally for helping fabrics to determine overflow/underflow
status, and has been superceeded by SCF_OVERFLOW_BIT + SCF_UNDERFLOW_BIT.
Signed-off-by: Roland Dreier <roland@purestorage.com>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
This patch fixes a regression bug with the handling of zero-length
data CDBs within transport_generic_new_cmd() code. The bug was introduced
with the following commit as part of the single task conversion work:
commit 4101f0a89d
Author: Christoph Hellwig <hch@infradead.org>
Date: Tue Apr 24 00:25:03 2012 -0400
target: always allocate a single task
where the zero-length check for SCF_SCSI_DATA_SG_IO_CDB was incorrectly
changed to SCF_SCSI_CONTROL_SG_IO_CDB because of the seperate comment
in transport_generic_new_cmd() wrt to control CDBs zero-length handling
introduced in:
commit 91ec1d3535
Author: Nicholas Bellinger <nab@linux-iscsi.org>
Date: Fri Jan 13 12:01:34 2012 -0800
target: Add workaround for zero-length control CDB handling
So go ahead and change transport_generic_new_cmd() to handle control+data
zero-length CDBs in the same manner for this special case.
Tested with iscsi-target + loopback fabric port LUNs on 3.6-rc0 code.
This patch will also need to be picked up for 3.5-stable.
(hch: Add proper comment in transport_generic_new_cmd)
Cc: Christoph Hellwig <hch@lst.de>
Cc: Roland Dreier <roland@purestorage.com>
Cc: Andy Grover <agrover@redhat.com>
Cc: stable@vger.kernel.org
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
I am hitting this bug when the target is low in memory that fails the
alloc_page() for the newly submitted command. This is a sort of off-by-one
bug causing NULL pointer dereference in __free_page() since 'i' here is
really the counter of total pages that have been successfully allocated here.
Signed-off-by: Yi Zou <yi.zou@intel.com>
Cc: Andy Grover <agrover@redhat.com>
Cc: Nicholas Bellinger <nab@linux-iscsi.org>
Cc: Open-FCoE.org <devel@open-fcoe.org>
Cc: stable@vger.kernel.org
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
During a failure in transport_add_device_to_core_hba() code, we called
destroy_workqueue(dev->tmr_wq) before ->tmr_wq was allocated which leads
to an oops.
This fixes a regression introduced in with:
commit af8772926f
Author: Christoph Hellwig <hch@infradead.org>
Date: Sun Jul 8 15:58:49 2012 -0400
target: replace the processing thread with a TMR work queue
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Cc: Christoph Hellwig <hch@lst.de>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
We want it to be possible for target_submit_cmd() to return errors up
to its fabric module callers. For now just update the prototype to
return an int, and update all callers to handle non-zero return values
as an error.
This is immediately useful for tcm_qla2xxx to fix a long-standing active
I/O session shutdown race, but tcm_fc, usb-gadget, and sbp-target the
fabric maintainers need to check + ACK that handling a target_submit_cmd()
failure due to session shutdown does not introduce regressions
(nab: Respin against for-next after initial NACK + update docbook comment +
fix double se_cmd init in exception path for usb-gadget)
Cc: Chad Dupuis <chad.dupuis@qlogic.com>
Cc: Arun Easi <arun.easi@qlogic.com>
Cc: Chris Boot <bootc@bootc.net>
Cc: Stefan Richter <stefanr@s5r6.in-berlin.de>
Cc: Mark Rustad <mark.d.rustad@intel.com>
Cc: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Cc: Felipe Balbi <balbi@ti.com>
Cc: Andy Grover <agrover@redhat.com>
Signed-off-by: Roland Dreier <roland@purestorage.com>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
Many SCSI commands are defined to return a CHECK CONDITION / ILLEGAL
REQUEST with ASC set to LOGICAL BLOCK ADDRESS OUT OF RANGE if the
initiator sends a command that accesses a too-big LBA. Add an enum
value and case entries so that target code can return this status.
Signed-off-by: Roland Dreier <roland@purestorage.com>
Cc: stable@vger.kernel.org
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
Since we set se_session.sess_tearing_down and stop new commands from
being added to se_session.sess_cmd_list before we wait for commands to
finish when freeing a session, there's no need for a separate
sess_wait_list -- if we let new commands be added to sess_cmd_list
after setting sess_tearing_down, that would be a bug that breaks the
logic of waiting in-flight commands.
Also rename target_splice_sess_cmd_list() to
target_sess_cmd_list_set_waiting(), since we are no longer splicing
onto a separate list.
Signed-off-by: Roland Dreier <roland@purestorage.com>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
Target core code assumes that target_splice_sess_cmd_list() has set
sess_tearing_down and moved the list of pending commands to
sess_wait_list, no more commands will be added to the session; if any
are added, nothing keeps the se_session from being freed while the
command is still in flight, which e.g. leads to use-after-free of
se_cmd->se_sess in target_release_cmd_kref().
To enforce this invariant, put a check of sess_tearing_down inside of
sess_cmd_lock in target_get_sess_cmd(); any checks before this are
racy and can lead to the use-after-free described above. For example,
the qla_target check in qlt_do_work() checks sess_tearing_down from
work thread context but then drops all locks before calling
target_submit_cmd() (as it must, since that is a sleeping function).
However, since no locks are held, anything can happen with respect to
the session it has looked up -- although it does correctly get
sess_kref within its lock, so the memory won't be freed while
target_submit_cmd() is actually running, nothing stops eg an ACL from
being dropped and calling ->shutdown_session() (which calls into
target_splice_sess_cmd_list()) before we get to target_get_sess_cmd().
Once this happens, the se_session memory can be freed as soon as
target_submit_cmd() returns and qlt_do_work() drops its reference,
even though we've just added a command to sess_cmd_list.
To prevent this use-after-free, check sess_tearing_down inside of
sess_cmd_lock right before target_get_sess_cmd() adds a command to
sess_cmd_list; this is synchronized with target_splice_sess_cmd_list()
so that every command is either waited for or not added to the queue.
(nab: Keep target_submit_cmd() returning void for now..)
Signed-off-by: Roland Dreier <roland@purestorage.com>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
There are no in-tree users of target_get_sess_cmd() outside of
target_core_transport.c. Any new code should use the higher-level
target_submit_cmd() interface. So let's un-export target_get_sess_cmd()
and make it static to the one file where it's actually used.
(nab: Fix up minor fuzz to for-next)
Signed-off-by: Roland Dreier <roland@purestorage.com>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
The last functionality of the target processing thread is offloading possibly
long running task management requests from the submitter context. To keep
TMR semantics the same we need a single threaded ordered queue, which can
be provided by a per-device workqueue with the right flags.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
Remove this command submission path which is not used by any in-tree driver.
This also removes the now unused new_cmd_map fabtric method, which a few
drivers implemented despite never calling transport_generic_handle_cdb_map.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
There is no need to schedule the delayed processing in a workqueue that
offloads it to the target processing thread. Instead execute it directly
from the workqueue. There will be a lot of future work in this area,
which I'd likfe to defer for now as it is not nessecary for getting rid
of the target processing thread.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
When we call target_execute_cmd for write commands the command has been
on the state list before an abort might have come in before
target_execute_cmd. Call transport_check_aborted_status to deal with
this case.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
Just call target_execute_cmd directly. Also, convert loopback, sbp,
usb-gadget to use the newly exported target_execute_cmd().
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
Inline the transport_off == 0 case into target_execute_cmd to simplify
the function for the remaining cases.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
Remove the execute_cmd method in struct se_subsystem_api, and always use the
one directly in struct se_cmd. To make life simpler for SBC virtual backends
a struct spc_ops that is passed to sbc_parse_cmd is added. For now it
only contains an execute_rw member, but more will follow with the subsequent
commits.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
Remove the dead SCF_SE_ALLOW_EOO and SCF_DELAYED_CMD_FROM_SAM_ATTR
from se_cmd_flags_table.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
Since "target: Drop se_device TCQ queue_depth usage from I/O path" we always
submit all commands (or back then, tasks) from __transport_execute_tasks.
That means the the execute list has lots its purpose, as we can simply
submit the commands that are restarted in transport_complete_task_attr
directly while we walk the list. In fact doing so also solves a race
in the way it currently walks to delayed_cmd_list as well.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
The virtual drivers don't need to clear cdb fields they never look at, so move
this code into the pscsi backend.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
Move the existing code in target_core_cdb.c into the files for the command
sets that the emulations implement.
(roland + nab: Squash patch: Fix range calculation in WRITE SAME emulation
when num blocks == 0s)
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
Instead of trying to handle all SCSI command sets in one function
(transport_generic_cmd_sequencer) call out to the backend driver to perform
this functionality. For pSCSI a copy of the existing code is used, but for
all virtual backends we can use a new parse_sbc_cdb helper is used to
provide a simple SBC emulation.
For now this setups means a fair amount of duplication between pSCSI and the
SBC library, but patches later in this series will sort out that problem.
(nab: Fix up build failure in target_core_pscsi.c)
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
We don't need three flags to classifiy the CDB as we can check for a NULL S/G
list for a dataless command, and can infer from the absence of the data flag
that we deal with a control CDB. Also remove the _SG_IO from the data CDB
flag as all I/O is dont on S/G lists now.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
Move all code not related to cdb parsing from transport_generic_cmd_sequencer
into target_setup_cmd_from_cdb.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
This patch adds an optional target_core_fabric_ops->put_session() caller
within the existing target_put_session() code path.
This is required by tcm_qla2xxx code in order to invoke it's own fabric
specific session shutdown handler using se_session->sess_kref.
Signed-off-by: Joern Engel <joern@logfs.org>
Cc: Roland Dreier <roland@purestorage.com>
Cc: Arun Easi <arun.easi@qlogic.com>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
The cdrecord uses ATA_PASS_THROUGH_16 command while burning CDs
with a SATA CD-ROM. This patch adds support to it so that PSCSI
CD-ROM passthrough works with the cdrecord.
(nab: Add !passthrough check to prevent non pSCSI backends from ATA_16)
Signed-off-by: Cong Meng <mc@linux.vnet.ibm.com>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
This patch fixes the MAINTENANCE_IN service action type checks to only
look at the proper lower 5 bits of cdb byte 1. This addresses the case
where MI_REPORT_TARGET_PGS w/ extended header using the upper three bits of
cdb byte 1 was not processed correctly in transport_generic_cmd_sequencer,
as well as the three cases for standby, unavailable, and transition ALUA
primary access state checks.
Also add MAINTENANCE_IN to the excluded list in transport_generic_prepare_cdb()
to prevent the PARAMETER DATA FORMAT bits from being cleared.
Cc: Hannes Reinecke <hare@suse.de>
Cc: Rob Evers <revers@redhat.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Roland Dreier <roland@purestorage.com>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
Some legacy OS use WRITE_VERIFY on hard disks.
Signed-off-by: Bernhard Kohl <bernhard.kohl@gmx.net>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
The function is effectively void and doesn't need any goto logic.
Signed-off-by: Joern Engel <joern@logfs.org>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
This patch removes the original usage of dev_attr->max_sectors in favor of
dev_attr->hw_max_sectors that is now being enforced by target core from
within transport_generic_cmd_sequencer() for SCF_SCSI_DATA_SG_IO_CDB ops.
After the recent se_task removal patches from hch, this value for IBLOCK
backends being set via configfs by userspace from an saved max_sectors
value that is turning out to be problematic, so it makes sense to go ahead
and remove this now legacy attribute all-together.
This patch also continues to make se_dev_set_default_attribs() do
(sectors / block_size) alignment for what actually get used by
target_core_mod to be safe here, following the same alignment currently
used by fabric_max_sectors.
Reported-by: Andy Grover <agrover@redhat.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Roland Dreier <roland@purestorage.com>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
target_stop_cmd() returns with the lock held and IRQs disabled. The
intent was to unlock here. This bug was originally added with:
commit cf572a9627
Author: Christoph Hellwig <hch@infradead.org>
Date: Tue Apr 24 00:25:05 2012 -0400
target: move the state and execute lists to the command
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
Nicholas Bellinger