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Commit Graph

77 Commits

Author SHA1 Message Date
Christoph Hellwig
b7b8bef7f8 target: use transport_cmd_check_stop_to_fabric consistently
Change one remaining user of transport_cmd_check_stop(cmd, 2, 0) to the
transport_cmd_check_stop_to_fabric wrapper.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
2011-10-24 03:21:37 +00:00
Christoph Hellwig
3df8d40ba3 target: do not pass the queue object to transport_remove_cmd_from_queue
We always operated on the same queue, so move finding it into the function,
just like we do for all other helpers operating on it.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
2011-10-24 03:21:36 +00:00
Christoph Hellwig
f7a5cc0b31 target: remove SCF_EMULATE_QUEUE_FULL
Add a new boolean at_head parameter to transport_add_cmd_to_queue and thus
obsolete the SCF_EMULATE_QUEUE_FULL flag.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
2011-10-24 03:21:34 +00:00
Christoph Hellwig
e057f53308 target: remove the transport_qf_callback se_cmd callback
Remove the need for the transport_qf_callback callback by making
sure we have specific states with specific handlers for the two
queue full cases.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
2011-10-24 03:21:32 +00:00
Christoph Hellwig
b937d27052 target: remove the ->transport_split_cdb callback in se_cmd
Add a switch statement implementing the CDB LBA/len update directly
in target_get_task_cdb and remove the old ->transport_split_cdb
callback and all its implementations.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
2011-10-24 03:21:15 +00:00
Christoph Hellwig
485fd0d1e3 target: replace ->get_cdb with a target_get_task_cdb helper
Instead of calling out to the backends from the core to get a per-task
CDB and then modify it for the LBA/len pair used for this CDB provide
a helper that writes the adjusted CDB into a provided buffer and call
this method from ->do_task in pscsi.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
2011-10-24 03:21:13 +00:00
Christoph Hellwig
6193f06e6f target: make the ->get_cdb method optional
The most commonly used file, iblock and rd backends have no use for
a per-task CDB and thus don't need a method to copy it into their
otherwise unused CDB fields.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
2011-10-24 03:21:11 +00:00
Christoph Hellwig
04629b7bde target: Remove unnecessary se_task members
This is a squashed version of the following unnecessary se_task structure
member removal patches:

target: remove the task_execute_queue field in se_task

    Instead of using a separate flag we can simply do list_emptry checks
    on t_execute_list if we make sure to always use list_del_init to remove
    a task from the list.  Also factor some duplicate code into a new
    __transport_remove_task_from_execute_queue helper.

target: remove the read-only task_no field in se_task

    The task_no field never was initialized and only used in debug printks,
    so kill it.

target: remove the task_padded_sg field in se_task

    This field is only check in one place and not actually needed there.

    Rationale:
    - transport_do_task_sg_chain asserts that we have task_sg_chaining
      set early on
    - we only make use of the sg_prev_nents field we calculate based on it
      if there is another sg list that gets chained onto this one, which
      never happens for the last (or only) task.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
2011-10-24 03:21:08 +00:00
Christoph Hellwig
6c76bf951c target: make more use of the task_flags field in se_task
Replace various atomic_t variables that were mostly under t_state_lock
with new flags in task_flags.  Note that the execution error path
didn't take t_state_lock before, so add it there.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
2011-10-24 03:21:06 +00:00
Christoph Hellwig
42bf829eee target: Cleanup unused se_task bits
This is a squashed version of the following se_task cleanup patches:

    target: remove the unused task_state_flags field in se_task
    target: remove the unused se_obj_ptr field in se_task
    target: remove the se_dev field in se_task

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
2011-10-24 03:21:05 +00:00
Christoph Hellwig
c0427f1556 target: Cleanup unused target_core_base.h bits
This is a squashed version of the following target_core_base.h
cleanup patches:

    target: remove the unused SHUTDOWN_SIGS defintion
    target: remove unused se_mem leftovers
    target: remove the unused map_func_t typedef
    target: move TRANSPORT_IOV_DATA_BUFFER to the iscsi-specific code

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
2011-10-24 03:21:03 +00:00
Nicholas Bellinger
ce8762f6cd target: Remove legacy + unused device active I/O shutdown code
This patch removes the legacy device active I/O shutdown code that was
originally called from transport_processing_thread() context during shutdown
including transport_processing_shutdown() and transport_release_all_cmds().

This is due to the fact that in modern configfs control plane code by the
time shutdown of an se_device instance in transport_processing_thread()
is allowed to occur via:

	rmdir /sys/kernel/config/target/core/$HBA/$DEV

all active I/O will already have been ceased while removing active configfs
fabric Port/LUN symlinks.  Eg: the removal of an active se_device is protected
by inter-module VFS references from active Port/LUN symlinks.

Two WARN_ON() checks have been added in their place before exiting
transport_processing_thread() to watch out for any leaked descriptors.

Cc: Christoph Hellwig <hch@lst.de>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
2011-10-24 03:20:59 +00:00
Nicholas Bellinger
8dc52b5420 target: Merge transport_cmd_finish_abort_tmr into transport_cmd_finish_abort
This patch merges transport_cmd_finish_abort_tmr() logic into a single
transport_cmd_finish_abort() function by adding a cmd->se_tmr_req check
around transport_lun_remove_cmd(), and updates the single caller within
core_tmr_drain_tmr_list().

Reported-by: Christoph Hellwig <hch@lst.de>
Cc: Christoph Hellwig <hch@lst.de>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
2011-10-24 03:20:58 +00:00
Nicholas Bellinger
d14921d6ad target: Convert ->transport_wait_for_tasks usage to transport_generic_free_cmd
This patch converts se_cmd->transport_wait_for_tasks(se_cmd, 1) usage to use
transport_generic_free_cmd() directly in target-core and iscsi-target fabric
usage.  The includes:

*) Removal of the optional transport_generic_free_cmd() call from within
   transport_generic_wait_for_tasks()
*) Usage of existing SCF_SUPPORTED_SAM_OPCODE to determine when
   transport_generic_wait_for_tasks() processing may occur instead of
   checking se_cmd->transport_wait_for_tasks()
*) Move transport_generic_wait_for_tasks() call ahead of core_dec_lacl_count()
   and transport_lun_remove_cmd() in transport_generic_free_cmd() to follow
   existing logic for iscsi-target w/ se_cmd->transport_wait_for_tasks(se_cmd, 1)
*) Removal of se_cmd->transport_wait_for_tasks() function pointer
*) Rename transport_generic_wait_for_tasks() -> transport_wait_for_tasks(), and
   add docbook comment.
*) Add EXPORT_SYMBOL for transport_wait_for_tasks()

For the case in iscsi_target_erl2.c:iscsit_prepare_cmds_for_realligance()
where se_cmd->transport_wait_for_tasks(se_cmd, 0) is called, this patch
adds a direct call to transport_wait_for_tasks().

(hch: Fix transport_generic_free_cmd() usage in iscsit_release_commands_from_conn)
(nab: Add patch: Ensure that TMRs hit wait_for_tasks logic during release)

Reported-by: Christoph Hellwig <hch@lst.de>
Cc: Christoph Hellwig <hch@lst.de>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
2011-10-24 03:20:54 +00:00
Christoph Hellwig
a3eedc227b target: remove unused se_subsystem_api methods
The cdb_none, map_data_SG and map_control_SG methods have no callers left
and can be removed now.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
2011-10-24 03:20:46 +00:00
Nicholas Bellinger
39c05f321a target: Remove session_reinstatement parameter from ->transport_wait_for_tasks
This patch removes the unnecessary session_reinstatement parameter from
se_cmd->transport_wait_for_tasks(), logic in transport_generic_wait_for_tasks,
and usage within iscsi-target code.

This also includes the removal of the 'bool' return from transport_put_cmd() +
transport_generic_free_cmd() that is no longer necessary.

Cc: Christoph Hellwig <hch@lst.de>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
2011-10-24 03:20:39 +00:00
Christoph Hellwig
82f1c8a4e7 target: push session reinstatement out of transport_generic_free_cmd
Push session reinstatement out of transport_generic_free_cmd into the only
caller that actually needs it.  Clean up transport_generic_free_cmd a bit,
and remove the useless comment.  I'd love to add a more useful kerneldoc
comment for it, but as this point I'm still a bit confused in where it
stands in the command release stack.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
2011-10-24 03:20:38 +00:00
Christoph Hellwig
e6a2573f1f target: remove transport_generic_remove
All callers that never have the session_reinstatement flag set can trivially
be converted to transport_put_cmd.  Opencode the session reinstatement code
in transport_generic_free_cmd, which was the only caller ever asking for it.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
2011-10-24 03:20:36 +00:00
Christoph Hellwig
4911e3ccbe target: simplify transport_put_cmd
Inline two simple functions only used by it, and replace a goto
with a simple if else construct.

Note that the code moved from transport_dec_and_check seems fairly
buggy - the atomic_read check on a variable where we'd do an
atomic_dec_and_test looks racy if we'll ever get someone increment
it without the lock held around them (which it looks like we do),
and not decrementing the second counter if the first one doesn't
hit zero also at least needs an explanation.

(nab: Fix transport_put_cmd breakage)

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
2011-10-24 03:20:34 +00:00
Christoph Hellwig
d3df7825ae target: simplify transport_generic_remove
Instead of duplicating the code from transport_release_fe_cmd re-use it by
allowing transport_release_fe_cmd to return wether it actually freed the
command or not.  Also rename transport_release_fe_cmd to transport_put_cmd
and add a kerneldoc comment for it to make the use case more obvious.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
2011-10-24 03:20:33 +00:00
Christoph Hellwig
2dbc43d256 target: remove transport_free_se_cmd
It is only called by transport_release_cmd, so inline it there.  Also add
a kerneldoc comment for transport_release_cmd while we are at it.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
2011-10-24 03:20:31 +00:00
Christoph Hellwig
31afc39c0c target: don't opencode transport_release_cmd in transport_release_fe_cmd
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
2011-10-24 03:20:29 +00:00
Christoph Hellwig
680b73c5f2 target: remove transport_generic_handle_cdb
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
2011-10-24 03:20:28 +00:00
Nicholas Bellinger
c252f00347 target: Prevent transport_send_task_abort when CHECK_CONDITION status
This patch fixes a bug where transport_send_task_abort() could be called
during LUN_RESET to return SAM_STAT_TASK_ABORTED + tfo->queue_status(), when
SCF_SENT_CHECK_CONDITION -> tfo->queue_status() has already been sent from
within another context via transport_send_check_condition_and_sense().

Cc: stable@kernel.org
Signed-off-by: Nicholas Bellinger <nab@risingtidesystems.com>
2011-10-24 03:20:12 +00:00
Nicholas Bellinger
77039d1eaf target: Fix transport_cmd_finish_abort queue removal bug
This patch fixes a bug in LUN_RESET operation with transport_cmd_finish_abort()
where transport_remove_cmd_from_queue() was incorrectly being called, causing
descriptors with t_state == TRANSPORT_FREE_CMD_INTR to be incorrectly removed
from qobj->qobj_list during process context release.  This change ensures the
descriptor is only removed via transport_remove_cmd_from_queue() when doing a
direct release via transport_generic_remove().

Cc: stable@kernel.org
Signed-off-by: Nicholas Bellinger <nab@risingtidesystems.com>
2011-10-24 03:20:01 +00:00
Roland Dreier
79a7fef264 target: Prevent cmd->se_queue_node double add
This patch addresses a bug with the lio-core-2.6.git conversion of
transport_add_cmd_to_queue() to use a single embedded list_head, instead
of individual struct se_queue_req allocations allowing a single se_cmd to
be added to the queue mulitple times.  This was changed in the following:

commit 2a9e4d5ca5d99f4c600578d6285d45142e7e5208
Author: Andy Grover <agrover@redhat.com>
Date:   Tue Apr 26 17:45:51 2011 -0700

    target: Embed qr in struct se_cmd

The problem is that some target code still assumes performing multiple
adds is allowed via transport_add_cmd_to_queue(), which ends up causing
list corruption in qobj->qobj_list code.  This patch addresses this
by removing an existing struct se_cmd from the list before the add, and
removes an unnecessary list walk in transport_remove_cmd_from_queue()

It also changes cmd->t_transport_queue_active to use explict sets intead
of increment/decrement to prevent confusion during exception path handling.

Signed-off-by: Roland Dreier <roland@purestorage.com>
Cc: Andy Grover <agrover@redhat.com>
Cc: stable@kernel.org
Signed-off-by: Nicholas Bellinger <nab@risingtidesystems.com>
2011-10-24 03:17:51 +00:00
Jesper Juhl
9375b1bfd2 target: Remove unneeded version.h includes
It was pointed out by 'make versioncheck' that some includes of
linux/version.h are not needed in drivers/target/.
This patch removes them.

Signed-off-by: Jesper Juhl <jj@chaosbits.net>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
2011-10-11 04:10:19 +00:00
Roland Dreier
bcac364a24 target: Fix race between multiple invocations of target_qf_do_work()
When work is scheduled with schedule_work(), the work can end up
running on multiple CPUs at the same time -- this happens if
the work is already running on one CPU and schedule_work() is called
on another CPU.  This leads to list corruption with target_qf_do_work(),
which is roughly doing:

	spin_lock(...);
	list_for_each_entry_safe(...) {
		list_del(...);
		spin_unlock(...);

		// do stuff

		spin_lock(...);
	}

With multiple CPUs running this code, one CPU can end up deleting the
list entry that the other CPU is about to work on.

Fix this by splicing the list entries onto a local list and then
operating on that in the work function.  This way, each invocation of
target_qf_do_work() operates on its own local list and so multiple
invocations don't corrupt each other's list.  This also avoids dropping
and reacquiring the lock for each list entry.

Signed-off-by: Roland Dreier <roland@purestorage.com>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
2011-09-16 09:29:20 +00:00
Roland Dreier
e63a8e1933 target: Make locking in transport_deregister_session() IRQ safe
At least the tcm_qla2xxx fabric driver calls into transport_deregister_session()
while holding an IRQ-disabled spinlock, so the inner locking needs to
use spin_lock_irqsave() instead of spin_lock_bh().

This fixes warnings seen with tcm_qla2xxx like:

    WARNING: at kernel/softirq.c:159 local_bh_enable_ip+0x98/0xb0()
    Call Trace:
     [<ffffffff8104e65f>] warn_slowpath_common+0x7f/0xc0
     [<ffffffff8104e6ba>] warn_slowpath_null+0x1a/0x20
     [<ffffffff81055368>] local_bh_enable_ip+0x98/0xb0
     [<ffffffff814d5284>] _raw_spin_unlock_bh+0x14/0x20
     [<ffffffffa027b7f6>] transport_deregister_session+0x96/0x180 [target_core_mod]
     [<ffffffffa00f7731>] tcm_qla2xxx_free_session+0xd1/0x170 [tcm_qla2xxx]
     [<ffffffffa01b9173>] qla_tgt_sess_put+0xc3/0x140 [qla2xxx]
     [<ffffffffa01bf40f>] qla_tgt_stop_phase1+0x8f/0x2c0 [qla2xxx]
     [<ffffffffa00f735e>] tcm_qla2xxx_tpg_store_enable+0x6e/0xd0 [tcm_qla2xxx]
     [<ffffffffa026ca29>] target_fabric_tpg_attr_store+0x39/0x40 [target_core_mod]
     [<ffffffffa00a575d>] configfs_write_file+0xbd/0x120 [configfs]
     [<ffffffff811464a6>] vfs_write+0xc6/0x180
     [<ffffffff811467c1>] sys_write+0x51/0x90
     [<ffffffff814dd382>] system_call_fastpath+0x16/0x1b

Signed-off-by: Roland Dreier <roland@purestorage.com>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
2011-08-22 19:26:33 +00:00
Nicholas Bellinger
c3c74c7a33 target: Fix task SGL chaining breakage with transport_allocate_data_tasks
This patch fixes two bugs associated with transport_do_task_sg_chain()
operation where transport_allocate_data_tasks() was incorrectly setting
task_padded_sg for all tasks, and causing bogus task->task_sg_nents
assignments + OOPsen with fabrics depending upon this code.  The first bit
here adds a task_sg_nents_padded check in transport_allocate_data_tasks()
to include an extra SGL vector when necessary for tasks that expect to
be linked using sg_chain().

The second change involves making transport_do_task_sg_chain() properly
account for the extra SGL vector when task->task_padded_sg is set for
the non trailing ->task_sg or single ->task_sg allocations.  Note this
patch also removes the BUG_ON(!task->task_padded_sg) check within
transport_do_task_sg_chain() as we expect this to happen normally
with the updated logic in transport_allocate_data_tasks(), along with
being bogus for CONTROL_SG_IO_CDB type payloads.

So far this bugfix has been tested with tcm_qla2xxx and iblock backends
in (task_count > 1)( and (task_count == 1) operation.

Reported-by: Kiran Patil <kiran.patil@intel.com>
Cc: Kiran Patil <kiran.patil@intel.com>
Cc: Andy Grover <agrover@redhat.com>
Cc: Christoph Hellwig <hch@lst.de>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
2011-08-22 19:26:28 +00:00
Nicholas Bellinger
525a48a21d target: Fix task count > 1 handling breakage and use max_sector page alignment
This patch addresses recent breakage with multiple se_task (task_count > 1)
operation following backend dev->se_sub_dev->se_dev_attrib.max_sectors in new
transport_allocate_data_tasks() code.  The initial bug here was a bogus
task->task_sg_nents assignment in transport_allocate_data_tasks() based on
the passed parameter, which now uses DIV_ROUND_UP(task_size, PAGE_SIZE) to
determine the proper number of per task SGL entries for the (task_count > 1)
case.

This also means we now need to enforce a PAGE_SIZE aligned max_sector count
value for this to work as expected without bringing back the pre v3.1
transport_map_mem_to_sg() logic to handle SGL offsets across multiple tasks.
So this patch adds se_dev_align_max_sectors() to round down max_sectors as
necessary to ensure this alignment via se_dev_set_default_attribs() and
se_dev_align_max_sectors() and keeps it simple for (task_count > 1)
operation.

So far this bugfix has been tested with (task_count > 1) operation
using iscsi-target and iblock backends.

Reported-by: Chris Boot <bootc@bootc.net>
Cc: Kiran Patil <kiran.patil@intel.com>
Cc: Andy Grover <agrover@redhat.com>
Cc: Christoph Hellwig <hch@lst.de>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
2011-08-22 19:26:27 +00:00
Nicholas Bellinger
01cde4d543 target: Add missing DATA_SG_IO transport_cmd_get_valid_sectors check
This patch adds the missing transport_cmd_get_valid_sectors() check for
SCF_SCSI_DATA_SG_IO_CDB type payloads to ensure that a received LBA + range
does not exeed past the end of associated backend struct se_device.

This patch also fixes a bug in the failure path of transport_new_cmd_obj()
where this check can fail, so change to use a signed 'rc' and return '-EINVAL'
to signal proper transport_generic_request_failure() handling.

Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
2011-08-22 19:26:26 +00:00
Nicholas Bellinger
7abbe7f3e4 target: Fix SYNCHRONIZE_CACHE zero LBA + range breakage
This patch fixes a SYNCHRONIZE_CACHE CDB handling bug with IBLOCK/FILEIO
backends where transport_cmd_get_valid_sectors() was incorrectly rejecting
a zero LBA + range CDB from being processed, and returning CHECK_CONDITION.

This includes changing transport_cmd_get_valid_sectors() to return '0' on
success and '-EINVAL' on failure (this makes more sense than sectors),
and to only check transport_cmd_get_valid_sectors() when a non zero LBA +
range SYNCHRONIZE_CACHE operation has been receieved for the non passthrough
case.

Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
2011-08-22 19:26:25 +00:00
Nicholas Bellinger
12850626e2 target: Fix WRITE_SAME usage with transport_get_size
For all flavours of WRITE_SAME, we only expect to handle a single block
of data-out buffer payload, regardless of the number of logical blocks
presented in the CDB.  This patch changes all flavours of WRITE_SAME in
transport_generic_cmd_sequencer() to pass '1' into transport_get_size()
instead of the extracted 'sectors' to properly handle the default usage
of sg_write_same without the --xferlen parameter.

Reported-by: Eric Seppanen <eric@purestorage.com>
Signed-off-by: Nicholas Bellinger <nab@risingtidesystems.com>
2011-08-22 19:26:22 +00:00
Nicholas Bellinger
706d586096 target: Add WRITE_SAME (10) parsing and refactor passthrough checks
This patch adds initial WRITE_SAME (10) w/ UNMAP=1 support following updates in
sbcr26 to allow UNMAP=1 for the non 16 + 32 byte CDB case.  It also refactors
current pSCSI passthrough passthrough checks into target_check_write_same_discard()
ahead of UNMAP=0 w/ write payload support into target_core_iblock.c.

This includes the support for handling WRITE_SAME in transport_emulate_control_cdb(),
and converts target_emulate_write_same to accept num_blocks directly for
WRITE_SAME, WRITE_SAME_16 and WRITE_SAME_32.

Reported-by: Eric Seppanen <eric@purestorage.com>
Cc: Roland Dreier <roland@purestorage.com>
Cc: Christoph Hellwig <hch@lst.de>
Signed-off-by: Nicholas Bellinger <nab@risingtidesystems.com>
2011-08-22 19:26:21 +00:00
Nicholas Bellinger
16ab8e60a0 target: Fix write payload exception handling with ->new_cmd_map
This patch fixes a bug for fabrics using tfo->new_cmd_map() that
are expect transport_generic_request_failure() to be calling
transport_send_check_condition_and_sense() for both READ and WRITE,
instead of only for READ exceptions.

This was originally observed with a failed WRITE_SAME_16 w/ unmap=0
using tcm_loop.

Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
2011-08-22 19:26:20 +00:00
Nicholas Bellinger
eb39d34004 target: Change TCM_NON_EXISTENT_LUN response to ASC=LOGICAL UNIT NOT SUPPORTED
This patch changes transport_send_check_condition_and_sense() for
TCM_NON_EXISTENT_LUN emulation to use 0x25 (LOGICAL UNIT NOT SUPPORTED)
instead of the original 0x20 (INVALID COMMAND OPERATION CODE).  This is
helpful to distinguish between TCM_UNSUPPORTED_SCSI_OPCODE ASC=0x20
exceptions.

Signed-off-by: Nicholas A. Bellinger <nab@risingtidesystems.com>
2011-08-17 00:50:02 +00:00
Nicholas Bellinger
dd8ae59d48 target: Fix bug for transport_generic_wait_for_tasks with direct operation
This patch fixes a bug in transport_handle_cdb_direct() usage with target_core
where transport_generic_wait_for_tasks() was bypassing active I/O + usage of
cmd->t_transport_stop_comp because cmd->t_transport_active=1 was not being set
before dispatching with transport_generic_new_cmd().  The fix follows existing
usage in transport_generic_handle_cdb*() -> transport_add_cmd_to_queue() and
set these directly, as well as handle transport_generic_new_cmd() exceptions
for QUEUE_FULL and CHECK_CONDITION instead of propigating up to RX context
fabric code.

The bug was manifesting itself with the following SLUB poison overwritten
warnings with iscsi-target v4.1 LUNs using the new process context direct
operation during session reinstatement with active I/O exception handling:

[885410.498267] =============================================================================
[885410.621622] BUG lio_cmd_cache: Poison overwritten
[885410.621791] -----------------------------------------------------------------------------
[885410.621792]
[885410.623420] INFO: 0xffff880000cf3750-0xffff880000cf378d. First byte 0x6a instead of 0x6b
[885410.626332] INFO: Allocated in iscsit_allocate_cmd+0x1c/0xd4 [iscsi_target_mod] age=345 cpu=1 pid=22554
[885411.855189] INFO: Freed in iscsit_release_cmd+0x208/0x217 [iscsi_target_mod] age=1410 cpu=1 pid=22554
[885411.856048] INFO: Slab 0xffffea000002d480 objects=22 used=0 fp=0xffff880000cf7300 flags=0x4080
[885411.856368] INFO: Object 0xffff880000cf33c0 @offset=13248 fp=0xffff880000cf6780

<SNIP>

[885411.955678] Pid: 22554, comm: iscsi_trx Not tainted 3.0.0-rc7+ #30
[885411.956040] Call Trace:
[885411.957029]  [<ffffffff810e5cf9>] print_trailer+0x12e/0x137
[885412.752879]  [<ffffffff810e61d9>] check_bytes_and_report+0xb9/0xfd
[885412.754933]  [<ffffffff810e62d2>] check_object+0xb5/0x192
[885412.755099]  [<ffffffff810e6445>] __free_slab+0x96/0x13a
[885412.757008]  [<ffffffff810e652a>] discard_slab+0x41/0x43
[885412.758171]  [<ffffffff810e7a4c>] __slab_free+0xf3/0xfe
[885412.761027]  [<ffffffffa030a536>] ? iscsit_release_cmd+0x208/0x217 [iscsi_target_mod]
[885412.761354]  [<ffffffff810e7e95>] kmem_cache_free+0x6f/0xac
[885412.761536]  [<ffffffffa030a536>] iscsit_release_cmd+0x208/0x217 [iscsi_target_mod]
[885412.762056]  [<ffffffffa020e467>] ? iblock_free_task+0x34/0x39 [target_core_iblock]
[885412.762368]  [<ffffffffa0314131>] lio_release_cmd+0x10/0x12 [iscsi_target_mod]
[885412.764129]  [<ffffffffa02c2254>] transport_release_cmd+0x2f/0x33 [target_core_mod]
[885412.805024]  [<ffffffffa02c230e>] transport_generic_remove+0xb6/0xc3 [target_core_mod]
[885412.806424]  [<ffffffff81035b5f>] ? try_to_wake_up+0x1bd/0x1bd
[885412.809033]  [<ffffffffa02c241f>] transport_generic_free_cmd+0x75/0x7d [target_core_mod]
[885412.810066]  [<ffffffffa02c2643>] transport_generic_wait_for_tasks+0x21c/0x22b [target_core_mod]
[885412.811056]  [<ffffffff8139f0b1>] ? mutex_lock+0x11/0x32
[885412.813059]  [<ffffffff8139f0b1>] ? mutex_lock+0x11/0x32
[885412.813200]  [<ffffffffa030b81d>] iscsit_close_connection+0x1d5/0x63a [iscsi_target_mod]
[885412.813517]  [<ffffffffa0300a82>] iscsit_take_action_for_connection_exit+0xdb/0xe0 [iscsi_target_mod]
[885412.813851]  [<ffffffffa03111e9>] iscsi_target_rx_thread+0x11f6/0x1221 [iscsi_target_mod]
[885412.829024]  [<ffffffff81033e8d>] ? pick_next_task_fair+0xbe/0x10e
[885412.831010]  [<ffffffffa030fff3>] ? iscsit_handle_scsi_cmd+0x91d/0x91d [iscsi_target_mod]
[885412.833011]  [<ffffffffa030fff3>] ? iscsit_handle_scsi_cmd+0x91d/0x91d [iscsi_target_mod]
[885412.835010]  [<ffffffff8105388a>] kthread+0x7d/0x85
[885412.837022]  [<ffffffff813a7124>] kernel_thread_helper+0x4/0x10
[885412.838008]  [<ffffffff8105380d>] ? kthread_worker_fn+0x145/0x145
[885412.840047]  [<ffffffff813a7120>] ? gs_change+0x13/0x13
[885412.842007] FIX lio_cmd_cache: Restoring 0xffff880000cf3750-0xffff880000cf378d=0x6

Cc: Christoph Hellwig <hch@lst.de>
Cc: Andy Grover <agrover@redhat.com>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
2011-07-30 12:01:25 +00:00
Nicholas Bellinger
5db0753ba5 target: Fix WRITE_SAME_16 lba assignment breakage
This patch fixes a bug in WRITE_SAME_16 LBA assignment where get_unaligned_be16()
is incorrectly being used instead of get_unaligned_be64() for a 64-bit LBA.

This was introduced with:

commit a1d8b49abd
Author: Andy Grover <agrover@redhat.com>
Date:   Mon May 2 17:12:10 2011 -0700

    target: Updates from AGrover and HCH (round 3)

    (target: inline struct se_transport_task into struct se_cmd)

Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
2011-07-28 06:14:49 +00:00
Nicholas Bellinger
277c5f27a2 target: Convert to DIV_ROUND_UP_SECTOR_T usage for sectors / dev_max_sectors
This patch adds the new macro usage of include/linux/kernel.h:DIV_ROUND_UP_SECTOR_T
for the new DIV_ROUND_UP_ULL() usage for 32-bit architectures with unsigned long long
sector_t division in transport_allocate_data_tasks() usage for target_core_mod v4.1

Reported-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Nicholas A. Bellinger <nab@linux-iscsi.org>
2011-07-26 09:40:34 +00:00
Andy Shevchenko
11650b8596 target: remove custom hex2bin() implementation
This patch drops transport_asciihex_to_binaryhex() in favor of proper
hex2bin usage from include/linux/kernel.h:hex2bin()

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
2011-07-22 09:37:49 +00:00
Nicholas Bellinger
1d20bb6147 target: ->map_task_SG conversion to ->map_control_SG and ->map_data_SG
This patch breaks up the ->map_task_SG() backend call into two seperate
->map_control_SG() and ->map_data_SG() in order to better address
IBLOCK and pSCSI.  IBLOCK only allocates bios for ->map_data_SG(), and
pSCSI will allocate a struct request for both cases.

This patch fixes incorrect usage of ->map_task_SG() for all se_cmd descriptors
in transport_generic_new_cmd() by moving the call into it's proper location
directly inside of transport_allocate_data_tasks()

Reported-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
2011-07-22 09:37:48 +00:00
Andy Grover
6708bb27bb target: Follow up core updates from AGrover and HCH (round 4)
This patch contains the squashed version of forth round series cleanups
from Andy and Christoph following the post heavy lifting in the preceeding:
'Eliminate usage of struct se_mem' and 'Make all control CDBs scatter-gather'
changes.  This also includes a conversion of target core and the v3.0
mainline fabric modules (loopback and tcm_fc) to use pr_debug and the
CONFIG_DYNAMIC_DEBUG infrastructure!

These have been squashed into this third and final round for v3.1.

target: Remove ifdeffed code in t_g_process_write
target: Remove direct ramdisk code
target: Rename task_sg_num to task_sg_nents
target: Remove custom debug macros for pr_debug. Use pr_err().
target: Remove custom debug macros in mainline fabrics
target: Set WSNZ=1 in block limits VPD. Abort if WRITE_SAME sectors = 0
target: Remove transport do_se_mem_map callback
target: Further simplify transport_free_pages
target: Redo task allocation return value handling
target: Remove extra parentheses
target: change alloc_task call to take *cdb, not *cmd

(nab: Fix bogus struct file assignments in fd_do_readv and fd_do_writev)

Signed-off-by: Andy Grover <agrover@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
2011-07-22 09:37:48 +00:00
Andy Grover
ec98f7825c target: Eliminate usage of struct se_mem
Both backstores and fabrics use arrays of struct scatterlist to describe
data buffers. However TCM used struct se_mems, basically a linked list
of scatterlist entries. We are able to simplify the code by eliminating
this intermediate data structure and just using struct scatterlist[]
throughout.

Also, moved attachment of task to cmd out of transport_generic_get_task
and into allocate_control_task and allocate_data_tasks. The reasoning
is that it's nonintuitive that get_task should automatically add it to
the cmd's task list -- it should just return an allocated, initialized
task. That's all it should do, based on the function's name, so either the
function shouldn't do it, or the name should change to encapsulate the
entire essence of what it does.

(nab: Fix compile warnings in tcm_fc, and make transport_kmap_first_data_page
 honor sg->offset for SGLs from contigious memory with TCM_Loop, and
 fix control se_cmd descriptor memory leak)

Signed-off-by: Andy Grover <agrover@redhat.com>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
2011-07-22 09:37:48 +00:00
Andy Grover
3a86720567 target: Pass 2nd param of transport_split_cdb by value
Since sectors is not modified, it's more straightforward to do this.

Signed-off-by: Andy Grover <agrover@redhat.com>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
2011-07-22 09:37:48 +00:00
Andy Grover
d0229ae3fe target: Enforce 1 page max for control cdb buffer sizes
Due to all cdbs' data buffers being referenced by scatterlists, buffers
of more than a page are not contiguous. Instead of handling this in all
control command handlers, we may be able to get away with just limiting
control cdb data buffers to one page. The only control CDBs we handle that
have potentially large data buffers are REPORT LUNS and UNMAP, so if we
didn't want to live with this limitation, they would need to be modified
to walk the pages in the data buffer's sgl.

Signed-off-by: Andy Grover <agrover@redhat.com>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
2011-07-22 09:37:48 +00:00
Andy Grover
05d1c7c0d0 target: Make all control CDBs scatter-gather
Previously, some control CDBs did not allocate memory in pages for their
data buffer, but just did a kmalloc. This patch makes all cdbs allocate
pages.

This has the benefit of streamlining some paths that had to behave
differently when we used two allocation methods. The downside is that
all accesses to the data buffer need to kmap it before use, and need to
handle data in page-sized chunks if more than a page is needed for a given
command's data buffer.

Finally, note that cdbs with no data buffers are handled a little
differently. Before, SCSI_NON_DATA_CDBs would not call get_mem at all
(they'd be in the final else in transport_allocate_resources) but now
these will make it into generic_get_mem, but just not allocate any
buffers.

Signed-off-by: Andy Grover <agrover@redhat.com>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
2011-07-22 09:37:48 +00:00
Nicholas Bellinger
07bde79a5c target: Add SCF_EMULATE_QUEUE_FULL -> transport_handle_queue_full
This patch adds SCF_EMULATE_QUEUE_FULL support using -EAGAIN failures
via transport_handle_queue_full() to signal queue full in completion
path TFO->queue_data_in() and TFO->queue_status() callbacks.

This is done using a new se_cmd->transport_qf_callback() to handle
the following queue full exception cases within target core:

*) TRANSPORT_COMPLETE_OK (for completion path queue full)

*) TRANSPORT_COMPLETE_QF_WP (for TRANSPORT_WRITE_PENDING queue full)

*) transport_send_check_condition_and_sense() failure paths in
   transport_generic_request_failure() and transport_generic_complete_ok()

All logic is driven using se_device->qf_work_queue -> target_qf_do_work()
to to requeue outstanding se_cmd at the head of se_dev->queue_obj->qobj_list
for transport_processing_thread() execution.

Tested using tcm_qla2xxx with MAX_OUTSTANDING_COMMANDS=128 for FCP READ
to trigger the TRANSPORT_COMPLETE_OK queue full cases, and a simulated
TFO->write_pending() -EAGAIN failure to trigger TRANSPORT_COMPLETE_QF_WP.

Reported-by: Roland Dreier <roland@purestorage.com>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
2011-07-22 09:37:45 +00:00
Nicholas Bellinger
695434e1cb target: Add transport_handle_cdb_direct optimization
This patch adds a transport_handle_cdb_direct() optimization for mapping
and queueing tasks directly from within fabric processing context by calling
the newly exported transport_generic_new_cmd().  This currently expects to
be called from process context only, and will fail if called within interrupt
context.

This patch also leaves transport_generic_handle_cdb() unmodified for the
moment to function as expected with existing tcm_fc and ib_srpt fabrics,
and will be removed once these have been converted and tested with v4.1
code using transport_handle_cdb_direct().

Based on Andy's original patch here:

[PATCH 39/42] target: Call transport_new_cmd instead of adding to cmd queue

Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
2011-07-22 09:37:44 +00:00
Christoph Hellwig
35462975b2 target: merge release_cmd methods
The release_cmd_to_pool and release_cmd_direct methods are always the same.
Merge them into a single release_cmd method, and clean up the fallout.

(nab: fix breakage in transport_generic_free_cmd() parameter build breakage
 in drivers/target/tcm_fc/tfc_cmd.c)

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
2011-07-22 09:37:44 +00:00