Commit Graph

154 Commits

Author SHA1 Message Date
Nicholas Bellinger
140854cb72 target: Convert session_lock to irqsave
This patch converts the remaining struct se_portal_group->session_lock
usage to use irqsave+irqrestore to address the following warnings for
hardware target mode interrupt context usage.  This change generate
other warnings for current iscsi-target mode still using ->session_lock
with spin_lock_bh, which will need to be converted in a seperate patch.

[  492.480728] [ INFO: HARDIRQ-safe -> HARDIRQ-unsafe lock order detected ]
[  492.488194] 3.0.0+ #23
[  492.490820] ------------------------------------------------------
[  492.497704] sh/7162 [HC0[0]:SC0[2]:HE0:SE0] is trying to acquire:
[  492.504493] (&(&se_tpg->session_lock)->rlock){+.....}, at: [<ffffffffa022364d>] transport_deregister_session+0x2d/0x163 [target_core_mod]
  492.518390]
[  492.518390] and this task is already holding:
[  492.524897] (&(&ha->hardware_lock)->rlock){-.-...}, at: [<ffffffffa00b9146>] qla_tgt_stop_phase1+0x5e/0x27e [qla2xxx]
[  492.536856] which would create a new lock dependency:
[  492.542481] (&(&ha->hardware_lock)->rlock){-.-...} -> (&(&se_tpg->session_lock)->rlock){+.....}
[  492.552321]
[  492.552321] but this new dependency connects a HARDIRQ-irq-safe lock:
[  492.561149] (&(&ha->hardware_lock)->rlock){-.-...}
[  492.566400] ... which became HARDIRQ-irq-safe at:
[  492.571841]   [<ffffffff81064720>] __lock_acquire+0x68f/0x921
[  492.578247]   [<ffffffff81064eff>] lock_acquire+0xe0/0x10d
[  492.584367]   [<ffffffff813a74c6>] _raw_spin_lock_irqsave+0x44/0x56
[  492.591358]   [<ffffffffa009b1be>] qla24xx_msix_default+0x5c/0x2aa [qla2xxx]
[  492.599227]   [<ffffffff81088582>] handle_irq_event_percpu+0x5a/0x197
[  492.606413]   [<ffffffff810886fb>] handle_irq_event+0x3c/0x5c
[  492.612822]   [<ffffffff8108a6dc>] handle_edge_irq+0xcc/0xf1
[  492.619138]   [<ffffffff810039b9>] handle_irq+0x83/0x8e
[  492.624971]   [<ffffffff8100333e>] do_IRQ+0x48/0xaf
[  492.630413]   [<ffffffff813a7cd3>] ret_from_intr+0x0/0x1a
[  492.636437]   [<ffffffff81001dc1>] cpu_idle+0x5b/0x8d
[  492.642073]   [<ffffffff81392709>] rest_init+0xad/0xb4
[  492.647809]   [<ffffffff81a1cbbc>] start_kernel+0x366/0x371
[  492.654030]   [<ffffffff81a1c2b1>] x86_64_start_reservations+0xb8/0xbc
[  492.661311]   [<ffffffff81a1c3b6>] x86_64_start_kernel+0x101/0x110
[  492.668204]
[  492.668205] to a HARDIRQ-irq-unsafe lock:
[  492.674324] (&(&se_tpg->session_lock)->rlock){+.....}
[  492.679862] ... which became HARDIRQ-irq-unsafe at:
[  492.685497] ...  [<ffffffff8106479a>] __lock_acquire+0x709/0x921
[  492.692209]   [<ffffffff81064eff>] lock_acquire+0xe0/0x10d
[  492.698330]   [<ffffffff813a75ed>] _raw_spin_lock_bh+0x31/0x40
[  492.704836]   [<ffffffffa021c208>] core_tpg_del_initiator_node_acl+0x89/0x336 [target_core_mod]
[  492.714546]   [<ffffffffa02fb075>] tcm_qla2xxx_drop_nodeacl+0x20/0x2d [tcm_qla2xxx]
[  492.723087]   [<ffffffffa02108d9>] target_fabric_nacl_base_release+0x22/0x24 [target_core_mod]
[  492.732698]   [<ffffffffa01661c8>] config_item_release+0x7d/0xa3 [configfs]
[  492.740465]   [<ffffffff811d48fe>] kref_put+0x43/0x4d
[  492.746101]   [<ffffffffa0166149>] config_item_put+0x19/0x1b [configfs]
[  492.753481]   [<ffffffffa0164987>] configfs_rmdir+0x1eb/0x258 [configfs]
[  492.760957]   [<ffffffff810ecc54>] vfs_rmdir+0x79/0xd0
[  492.766690]   [<ffffffff810eec4a>] do_rmdir+0xc2/0x111
[  492.772423]   [<ffffffff810eecd0>] sys_rmdir+0x11/0x13
[  492.778156]   [<ffffffff813ae4d2>] system_call_fastpath+0x16/0x1b
[  492.784953]

Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
2012-03-10 13:59:03 -08:00
Nicholas Bellinger
c0974f8938 target: Allow target_submit_tmr interrupt context + pass ABORT_TASK tag
This patch allows target_submit_tmr() to pass gfp_t for se_cmd->se_tmr_req
allocation, and also set up se_cmd->se_tmr_req->ref_task_tag for passed
tag with TMR_ABORT_TASK.

Also update tcm_fc(fcoe) parameter usgae and add ref_task_tag FIXME
for TMR_ABORT_TASK usage,

Cc: Andy Grover <agrover@redhat.com>
Cc: Kiran Patil <kiran.patil@intel.com>
Cc: Arun Easi <arun.easi@qlogic.com>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
2012-02-25 18:39:13 -08:00
Nicholas Bellinger
9f0d05c2c6 target: Push target_submit_tmr LUN lookup failure to system_wq context
In order to handle incoming target_submit_tmr() callers using interrupt
context, use system_wq process context for transport_lookup_tmr_lun()
failures to return TMR_LUN_DOES_NOT_EXIST status for fabric TM response.

Cc: Andy Grover <agrover@redhat.com>
Cc: Kiran Patil <kiran.patil@intel.com>
Cc: Arun Easi <arun.easi@qlogic.com>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
2012-02-25 18:38:41 -08:00
Nicholas Bellinger
c7042cae58 target: Fix target_submit_tmr se_tmr_req allocation failures
This patch makes target_submit_tmr() se_tmr_req allocation occur before
target_get_sess_cmd(), and changes target_submit_tmr() to return a failure
w/ non zero status to the fabric caller upon core_tmr_alloc_req() failure.

Cc: Andy Grover <agrover@redhat.com>
Cc: Kiran Patil <kiran.patil@intel.com>
Cc: Arun Easi <arun.easi@qlogic.com>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
2012-02-25 18:38:34 -08:00
Nicholas Bellinger
3de55ec74a target: Fix target_submit_tmr LUN lookup failures
This patch changes target_submit_tmr() LUN lookup failures to set response
status TMR_LUN_DOES_NOT_EXIST and invoke TFO->queue_tm_rsp(), instead of
sending CHECK_CONDITION status that can cause problems with Linux FCoE
clients.

Tested with tcm_fc ports and explict LUN_RESET lookup failures.

Cc: Andy Grover <agrover@redhat.com>
Cc: Kiran Patil <kiran.patil@intel.com>
Cc: Arun Easi <arun.easi@qlogic.com>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
2012-02-25 14:37:51 -08:00
Roland Dreier
015487b89f target: Untangle front-end and back-end meanings of max_sectors attribute
se_dev_attrib.max_sectors currently has two independent meanings:

 - It is reported in the block limits VPD page as the maximum transfer
   length, ie the largest IO that the front-end (fabric) can handle.
   Also the target core doesn't enforce this maximum transfer length.

 - It is used to hold the size of the largest IO that the back-end can
   handle, so we know when to split SCSI commands into multiple tasks.

Fix this by adding a new se_dev_attrib.fabric_max_sectors to hold the
maximum transfer length, and checking incoming IOs against that limit.

Signed-off-by: Roland Dreier <roland@purestorage.com>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
2012-02-25 14:37:49 -08:00
Nicholas Bellinger
3d28934aaa target: Add TMR_ABORT_TASK task management support
This patch adds initial support for TMR_ABORT_TASK ops for se_cmd
descriptors using se_sess->sess_cmd_list and se_cmd->cmd_kref counting.

It will perform an explict abort for all outstanding se_cmd ops based
upon tmr->ref_task_tag that have not been set CMD_T_COMPLETE.
It will cancel se_cmd->work and wait for backing I/O to complete before
attempting to send SAM_STAT_TASK_ABORTED and perform
target_put_sess_cmd() to release the referenced descriptor.

It also adds a CMD_T_ABORTED check into transport_complete_task() to
catch the completion from backend I/O that has been aborted, and
updates transport_wait_for_tasks() to allow CMD_T_ABORTED usage with
core_tmr_abort_task() context.

Reported-by: Roland Dreier <roland@purestorage.com>
Cc: Christoph Hellwig <hch@lst.de>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
2012-02-25 14:37:49 -08:00
Nicholas Bellinger
ffc32d5259 target: Make target_release_cmd_kref release on empty list
This patch changes target_release_cmd_kref() to make TFO->release_cmd()
call when list_empty(&se_cmd->se_cmd_list) is TRUE.  This is required
for TMR_ABORT_TASK operation where the referenced tag descriptor may
have already been pulled of the session command list.

Reported-by: Roland Dreier <roland@purestorage.com>
Cc: Christoph Hellwig <hch@lst.de>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
2012-02-25 14:37:49 -08:00
Nicholas Bellinger
86715569d0 target: Add SCF_ACK_KREF flag for acknowledgement kref
When TARGET_SCF_ACK_KREF is in use with target_submit_cmd() for
setting the extra acknowledgement reference to se_cmd->cmd_kref,
go ahead and set SCF_ACK_KREF in order to be used later by
abort task.

Reported-by: Roland Dreier <roland@purestorage.com>
Cc: Christoph Hellwig <hch@lst.de>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
2012-02-25 14:37:49 -08:00
Nicholas Bellinger
2fbff1276b target: Export transport_generic_request_failure symbol
transport_generic_request_failure() is a wrapper around calling
transport_send_check_condition_and_sense() that is required once
an se_cmd->cmd_kref has been obtained via target_submit_cmd() ->
target_get_sess_cmd().

tcm_qla2xxx currently requires this, and since it's necessary for
other callers using target_submit_cmd() make it exportable now.

Reported-by: Roland Dreier <roland@purestorage.com>
Cc: Christoph Hellwig <hch@lst.de>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
2012-02-25 14:37:48 -08:00
Andy Grover
a1edf9cf6d target: Cleanup transport_kunmap_data_sg()
This code isn't broken per se, but it's scary to look at! It looks like
in the t_data_nents==1 case we're doing both a kunmap and a vunmap,
what's saving us is that t_data_vmap in this case is 0, so vunmap
doesn't do anything.

Return after kunmap, so the handling of the three cases does not overlap.

Signed-off-by: Andy Grover <agrover@redhat.com>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
2012-02-25 14:37:48 -08:00
Andy Grover
ea98d7f9c7 target: Add target_submit_tmr helper function
Similar to target_submit_cmd, this function lets fabrics call one function
(albeit with a lot of parameters) instead of 3 or more.

(nab: Add missing return for transport_lookup_tmr_lun failure)

Signed-off-by: Andy Grover <agrover@redhat.com>
Cc: Kiran Patil <kiran.patil@intel.com>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
2012-02-25 14:37:48 -08:00
Andy Grover
c8e31f26fe target: Add SCF_SCSI_TMR_CDB usage and drop se_tmr_req_cache
Change the test for if a cmd is a tmr request to checking if
SCF_SCSI_TMR_CDB (a new flag) is set in cmd->se_cmd_flags.

Also remove se_tmr_req_cache usage in favor of kzalloc usage,
and make core_tmr_alloc_req() return int + setup se_cmd->se_tmr_req
directly and fix up various fabric module usages

Cc: Andy Grover <agrover@redhat.com>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
2012-02-25 14:37:47 -08:00
Andy Grover
8e94b8db61 target: Use #define for SYNCHRONIZE_CACHE_16
Signed-off-by: Andy Grover <agrover@redhat.com>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
2012-02-25 14:37:46 -08:00
Christoph Hellwig
3d26fea01d target: remove the transport_lun_active field in struct se_cmd
There is no reason to have a flag telling if a command is on the per-lun list,
we can simply do a list_empty check before removing it as long as we're careful
to always use list_del_init.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
2012-02-25 14:37:46 -08:00
Christoph Hellwig
7d680f3b74 target: replace various cmd flags with a transport state
Replace various atomic_ts used as flags in struct se_cmd with a single
transport_state bitmap that requires t_state_lock to be held for modifications.

In the target core that assumption generally is true, but some recently added
code in the SRP target had to grow new lock calls.  I can't say I like the way
how it messes with the command state directly, but let's leave that for later.

(Re-add missing ib_srpt.c changes that nab dropped..)

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
2012-02-25 14:37:45 -08:00
Martin Svec
67236c4474 target: Fix unsupported WRITE_SAME sense payload
This patch fixes a bug in target-core where unsupported WRITE_SAME ops
from a target_check_write_same_discard() failure was incorrectly
returning CHECK_CONDITION w/ TCM_INVALID_CDB_FIELD sense data.
This was causing some clients to not properly fall back, so go ahead
and use the correct TCM_UNSUPPORTED_SCSI_OPCODE sense for this case.

Reported-by: Martin Svec <martin.svec@zoner.cz>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
2012-02-07 06:48:58 +00:00
Nicholas Bellinger
735703cac0 target: Fix target_submit_cmd() exception handling
This patch fixes a bug in target_submit_cmd() where the failure path
for transport_generic_allocate_tasks() made a direct call to
transport_send_check_condition_and_sense() and not calling the
final target_put_sess_cmd() release callback.

For transport_generic_allocate_tasks() failures, use the proper call to
transport_generic_request_failure() to handle kref_put() along
with potential internal queue full response processing.

It also makes transport_lookup_cmd_lun() failures in
target_submit_cmd() use transport_send_check_condition_and_sense() and
target_put_sess_cmd() directly to avoid se_cmd->se_dev reference in
transport_generic_request_failure() handling.

Finally it drops the out_check_cond: label and use direct reference for
allocate task failures, and per-se_device queue_full handling is
currently not supported for transport_lookup_cmd_lun() failure
descriptors due to se_device dependency.

Reported-by: Roland Dreier <roland@purestorage.com>
Cc: Roland Dreier <roland@purestorage.com>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
2012-02-07 06:47:11 +00:00
Andy Grover
1edcdb497e target: Change target_submit_cmd() to return void
Retval not very useful, and may even be harmful. Once submitted, fabrics
should expect a sense error if anything goes wrong. All fabrics checking
of this retval are useless or broken:

fc checks it just to emit more debug output.
ib_srpt trickles retval up, then it is ignored.
qla2xxx trickles it up, which then causes a bug because the abort goto
in qla_target.c thinks cmd hasn't been sent to target.

Just returning nothing is best.

Signed-off-by: Andy Grover <agrover@redhat.com>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
2012-02-07 06:41:04 +00:00
Andy Grover
4949314c72 target: Allow control CDBs with data > 1 page
We need to handle >1 page control cdbs, so extend the code to do a vmap
if bigger than 1 page. It seems like kmap() is still preferable if just
a page, fewer TLB shootdowns(?), so keep using that when possible.

Rename function pair for their new scope.

Signed-off-by: Andy Grover <agrover@redhat.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
2012-01-18 08:35:58 +00:00
Sebastian Andrzej Siewior
e59a41b69a target: avoid multiple outputs in scsi_dump_inquiry()
The multiple calls to pr_debug() each with one letter results in a new
line. This patch merges the multiple requests into one call per line
so we don't have the multiple line cuts.

Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
2012-01-18 08:30:36 +00:00
Nicholas Bellinger
91ec1d3535 target: Add workaround for zero-length control CDB handling
This patch adds a work-around for handling zero allocation length
control CDBs (type SCF_SCSI_CONTROL_SG_IO_CDB) that was causing an
OOPs with the following raw calls:

   # sg_raw -v /dev/sdd 3 0 0 0 0 0
   # sg_raw -v /dev/sdd 0x1a 0 1 0 0 0

This patch will follow existing zero-length handling for data I/O
and silently return with GOOD status.  This addresses the zero length
issue, but the proper long-term resolution for handling arbitary
allocation lengths will be to refactor out data-phase handling in
individual CDB emulation logic within target_core_cdb.c

Reported-by: Roland Dreier <roland@purestorage.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
2012-01-18 08:30:22 +00:00
Roland Dreier
9fbc890987 target: Correct sense key for INVALID FIELD IN {PARAMETER LIST,CDB}
According to SPC-4, the sense key for commands that are failed with
INVALID FIELD IN PARAMETER LIST and INVALID FIELD IN CDB should be
ILLEGAL REQUEST (5h) rather than ABORTED COMMAND (Bh).  Without this
patch, a tcm_loop LUN incorrectly gives:

    # sg_raw -r 1 -v /dev/sda 3 1 0 0 ff 0
    Sense Information:
     Fixed format, current;  Sense key: Aborted Command
     Additional sense: Invalid field in cdb
     Raw sense data (in hex):
            70 00 0b 00 00 00 00 0a  00 00 00 00 24 00 00 00
            00 00

While a real SCSI disk gives:

    Sense Information:
     Fixed format, current;  Sense key: Illegal Request
     Additional sense: Invalid field in cdb
     Raw sense data (in hex):
            70 00 05 00 00 00 00 18  00 00 00 00 24 00 00 00
            00 00 00 00 00 00 00 00  00 00 00 00 00 00 00 00

with the main point being that the real disk gives a sense key of
ILLEGAL REQUEST (5h).

Signed-off-by: Roland Dreier <roland@purestorage.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
2012-01-18 08:30:05 +00:00
roland@purestorage.com
9db9da3322 target: Don't zero pages used for data buffers
Doing alloc_page(GFP_KERNEL | __GFP_ZERO) to get pages used for data
buffers wastes a lot of CPU clearing pages that will be quickly be
overwritten by the actual data.  However, for emulated control
commands such as INQUIRY and so on, the code does assume that the
buffer is zeroed.

To avoid this CPU overhead, skip the __GFP_ZERO for commands that are
actually moving data, ie cmds that have SCF_SCSI_DATA_SG_IO_CDB set.

Signed-off-by: Roland Dreier <roland@purestorage.com>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
2012-01-18 08:29:57 +00:00
Roland Dreier
895f302252 target: Set additional sense length field in sense data
The target code was not setting the additional sense length field in the
sense data it returned, which meant that at least the Linux stack
ignored the ASC/ASCQ fields.  For example, without this patch, on a
tcm_loop device:

    # sg_raw -v /dev/sda 2 0 0 0 0 0

gives

        cdb to send: 02 00 00 00 00 00
    SCSI Status: Check Condition

    Sense Information:
     Fixed format, current;  Sense key: Illegal Request
      Raw sense data (in hex):
            70 00 05 00 00 00 00 00

while after the patch we correctly get the following (which matches what
a regular disk returns):

        cdb to send: 02 00 00 00 00 00
    SCSI Status: Check Condition

    Sense Information:
     Fixed format, current;  Sense key: Illegal Request
     Additional sense: Invalid command operation code
     Raw sense data (in hex):
            70 00 05 00 00 00 00 0a  00 00 00 00 20 00 00 00
            00 00

Signed-off-by: Roland Dreier <roland@purestorage.com>
Cc: stable@kernel.org
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
2011-12-16 06:29:04 +00:00
Nicholas Bellinger
6d5b597560 target: Remove legacy device status check from transport_execute_tasks
This patch removes a legacy se_dev_check_online() check from within
transport_execute_tasks() that should no longer be necessary as
transport_lookup_cmd_lun() is already making this call.

Using transport_cmd_check_stop() from transport_execute_tasks() should
already be checking per se_cmd context for each descriptor upon active
I/O shutdown, so no need to acquire dev->dev_status_lock again while
executing se_task submission.

Cc: Christoph Hellwig <hch@lst.de>
Cc: Roland Dreier <roland@purestorage.com>
Cc: Joern Engel <joern@logfs.org>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
2011-12-14 11:53:29 +00:00
Nicholas Bellinger
beb55a0cc1 target: Remove __transport_execute_tasks() for each processing context
This patch removes the original usage of __transport_execute_tasks() ahead
of every transport_get_cmd_from_queue() call in transport_processing_thread().
This helps reduce se_device->execute_task_lock contention between qla2xxx wq
with target_submit_cmd() for READs and transport_processing_thread()
context servicing WRITEs with full payloads for I/O submission.

It also adds a __transport_execute_tasks() to kick the task queue again
without a *se_cmd descriptor with existing queue full logic, but this may
end up not being necessary.

Cc: Christoph Hellwig <hch@lst.de>
Cc: Roland Dreier <roland@purestorage.com>
Cc: Joern Engel <joern@logfs.org>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
2011-12-14 11:50:12 +00:00
Nicholas Bellinger
4d2300ccff target: Remove extra se_device->execute_task_lock access in fast path
This patch makes __transport_execute_tasks() perform the addition of
tasks to dev->execute_task_list via __transport_add_tasks_from_cmd()
while holding dev->execute_task_lock during normal I/O fast path
submission.

It effectively removes the unnecessary re-acquire of dev->execute_task_lock
during transport_execute_tasks() -> transport_add_tasks_from_cmd() ahead
of calling  __transport_execute_tasks() to queue tasks for the passed
*se_cmd descriptor.

(v2: Re-add goto check_depth usage for multi-task submission for now..)

Cc: Christoph Hellwig <hch@lst.de>
Cc: Roland Dreier <roland@purestorage.com>
Cc: Joern Engel <joern@logfs.org>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
2011-12-14 11:48:46 +00:00
Nicholas Bellinger
65586d51e0 target: Drop se_device TCQ queue_depth usage from I/O path
Historically, pSCSI devices have been the ones that required target-core
to enforce a per se_device->depth_left.  This patch changes target-core
to no longer (by default) enforce a per se_device->depth_left or sleep in
transport_tcq_window_closed() when we out of queue slots for all backend
export cases.

Cc: Christoph Hellwig <hch@lst.de>
Cc: Roland Dreier <roland@purestorage.com>
Cc: Joern Engel <joern@logfs.org>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
2011-12-14 11:42:13 +00:00
Nicholas Bellinger
40be67f4c5 target: Fix possible NULL pointer with __transport_execute_tasks
This patch makes __transport_execute_tasks() use a local *se_dev
reference to prevent direct se_cmd->se_dev access after
transport_cmd_check_stop() -> transport_add_tasks_from_cmd()
has been called, as in the current implementation we can expect
__transport_execute_tasks() may be called from another context
that may have already completed the I/O.

Cc: Christoph Hellwig <hch@lst.de>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
2011-12-14 11:42:12 +00:00
Nicholas Bellinger
a636078552 target: Add target_submit_cmd() for process context fabric submission
This patch adds a target_submit_cmd() caller that can be used by fabrics
to submit an uninitialized se_cmd descriptor to an struct se_session +
unpacked_lun from workqueue process context.  This call will invoke the
following steps:

- transport_init_se_cmd() to setup se_cmd specific pointers
- Obtain se_cmd->cmd_kref references with target_get_sess_cmd()
- set se_cmd->t_tasks_bidi
- transport_lookup_cmd_lun() to setup struct se_cmd->se_lun from
  the passed unpacked_lun
- transport_generic_allocate_tasks() to setup the passed *cdb, and
- transport_handle_cdb_direct() handle READ dispatch or WRITE
  ready-to-transfer callback to fabric

v2 changes from hch feedback:

*) Add target_sc_flags_table for target_submit_cmd flags
*) Rename bidi parameter to flags, add TARGET_SCF_BIDI_OP
*) Convert checks to BUG_ON
*) Add out_check_cond for transport_send_check_condition_and_sense
   usage

v3 changes:

*) Add TARGET_SCF_ACK_KREF for target_submit_cmd into
   target_get_sess_cmd to determine when the fabric caller is expecting
   a second kref_put() from fabric packet acknowledgement.

Cc: Christoph Hellwig <hch@lst.de>
Cc: Roland Dreier <roland@purestorage.com>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
2011-12-14 11:40:56 +00:00
Nicholas Bellinger
7481deb413 target: Make target_put_sess_cmd use target_release_cmd_kref
This patch moves target_put_sess_cmd() to use a se_cmd->cmd_kref
callback target_release_cmd_kref when performing driver release of
fabric->se_cmd descriptor memory.  It sets the default cmd_kref
count value to '2' within target_get_sess_cmd() setup, and
currently assumes TFO->check_stop_free() usage.

It drops se_tfo->check_release_cmd() usage in the main
transport_release_cmd codepath.

Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
2011-12-14 11:38:29 +00:00
Jörn Engel
8359cf43b9 target: remove useless casts
A reader should spend an extra moment whenever noticing a cast,
because either something special is going on that deserves extra
attention or, as is all too often the case, the code is wrong.

These casts, afaics, have all been useless.  They cast a foo* to a
foo*, cast a void* to the assigned type, cast a foo* to void*, before
assigning it to a void* variable, etc.

In a few cases I also removed an additional &...[0], which is equally
useless.

Lastly I added three FIXMEs where, to the best of my judgement, the
code appears to have a bug.  It would be good if someone could check
these.

Signed-off-by: Joern Engel <joern@logfs.org>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
2011-12-14 11:28:07 +00:00
Christoph Hellwig
1880807adb target: make the se_task task_state_active a normal bool
There is no need to make task_state_active an atomic_t given that it is
always set under the execute_task_lock so we can make it a simple bool.
Also rename it to t_state_active to be closer to the list it guards,
and make sure all checks before the list addion/removal actually happen
under execute_task_lock.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
2011-12-14 11:27:02 +00:00
Christoph Hellwig
41e16e9816 target: remove the se_task task_error_status field
We only reach transport_complete_task once per task, so the test and set on
task_error_status is never going to have an effect.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
2011-12-14 11:26:44 +00:00
Christoph Hellwig
ef804a849f target: fold se_task.task_sense into task_flags
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
2011-12-14 11:26:27 +00:00
Christoph Hellwig
c4795fb20e target: header reshuffle, part2
This reorganized the headers under include/target into:

 - target_core_base.h stays as is with all target-wide data stuctures and defines
 - target_core_backend.h contains the whole interface to I/O backends
 - target_core_fabric.h contains the whole interface to fabric modules

Except for those only the various configfs macro headers stay around.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
2011-12-14 11:26:05 +00:00
Christoph Hellwig
e26d99aed4 target: reshuffle headers
Create a new headers, drivers/target/target_core_internal.h that is supposed
to hold all target_core-internal prototypes.  Move all non-exported includes
from include/target to it, and merge the smaller prototype-only includes
inside drivers/target into it as well.  Mark functions that were found to
not be called outside their implementation file static.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
2011-12-14 08:51:12 +00:00
Jörn Engel
5c73b678f7 target: remove unused struct fields
Some are never used, some are set but never read, dev_hoq_count is
incremented and decremented, but never read.

Signed-off-by: Joern Engel <joern@logfs.org>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
2011-12-06 06:00:56 +00:00
Roland Dreier
9b5cd7f37e target: Handle 0 correctly in transport_get_sectors_6()
SBC-3 says:

    A TRANSFER LENGTH field set to zero specifies that 256 logical
    blocks shall be written.  Any other value specifies the number
    of logical blocks that shall be written.

The old code was always just returning the value in the TRANSFER LENGTH
byte.  Fix this to return 256 if the byte is 0.

Signed-off-by: Roland Dreier <roland@purestorage.com>
Cc: stable@kernel.org
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
2011-12-06 06:00:55 +00:00
Roland Dreier
410f670202 target: Don't return an error status for 0-length READ and WRITE
IO commands with a TRANSFER LENGTH of 0 are not an error; for example,
for READ (10) and WRITE (10), SBC-3 says:

    A TRANSFER LENGTH field set to zero specifies that no logical blocks
    shall be read. This condition shall not be considered an error.

In case we have nothing to do, just complete the command with good status.

Signed-off-by: Roland Dreier <roland@purestorage.com>
Cc: stable@kernel.org
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
2011-12-06 06:00:55 +00:00
Nicholas Bellinger
fef58a6096 target: Reject SCSI data overflow for fabrics using transport_generic_map_mem_to_cmd
This patch changes transport_generic_map_mem_to_cmd() to reject SCSI data
overflow and to send exception status with CHECK_CONDITION + TCM_INVALID_CDB_FIELD
for fabrics that are passing a pre-populated struct scatterlist (eg: tcm_loop
and iscsi-target) being mapped into se_cmd->t_data_sg and se_cmd->t_data_nents.

This addresses an OOPs where transport_allocate_data_tasks() would walk
the incorrect post OVERFLOW cmd->data_length value beyond the end of
the passed scatterlist.

Cc: Christoph Hellwig <hch@lst.de>
Cc: Andy Grover <agrover@redhat.com>
Cc: stable@kernel.org
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
2011-12-06 06:00:53 +00:00
Christoph Hellwig
33c3fafc43 target: remove the t_tasks_bidi se_cmd field
And use a SCF_BIDI flag instead.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
2011-12-06 06:00:53 +00:00
Christoph Hellwig
2d3a4b51df target: remove the t_tasks_fua se_cmd field
And use a SCF_FUA flag instead.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
2011-12-06 06:00:52 +00:00
Christoph Hellwig
aad13ca20d target: remove the se_ordered_node se_cmd field
We never walk ordered_cmd_list in the se_device, so remove all code related
to supporting it.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
2011-12-06 06:00:52 +00:00
Christoph Hellwig
58a2801a4b target: remove the se_obj_ptr and se_orig_obj_ptr se_cmd fields
We already have a perfectly valid se_device pointer in the command, so
remove the mostly useless duplicates.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
2011-12-06 06:00:52 +00:00
Roland Dreier
97c34f3b04 target: Get rid of unused se_cmd_cache
Signed-off-by: Roland Dreier <roland@purestorage.com>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
2011-12-06 06:00:51 +00:00
Bart Van Assche
330694a50f target: Improve system responsivity during I/O
While testing ib_srpt I noticed that the target system became
rather unresponsive during intensive I/O. The patch below made
my target system responsive again during I/O without decreasing
performance.

Signed-off-by: Bart Van Assche <bvanassche@acm.org>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
2011-12-06 06:00:50 +00:00
Nicholas Bellinger
03e98c9eb9 target: Address legacy PYX_TRANSPORT_* return code breakage
This patch removes legacy usage of PYX_TRANSPORT_* return codes in a number
of locations and addresses cases where transport_generic_request_failure()
was returning the incorrect sense upon CHECK_CONDITION status after the
v3.1 converson to use errno return codes.

This includes the conversion of transport_generic_request_failure() to
process cmd->scsi_sense_reason and handle extra TCM_RESERVATION_CONFLICT
before calling transport_send_check_condition_and_sense() to queue up
response status.  It also drops PYX_TRANSPORT_OUT_OF_MEMORY_RESOURCES legacy
usgae, and returns TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE w/ a response
for these cases.

transport_generic_allocate_tasks(), transport_generic_new_cmd(), backend
SCF_SCSI_DATA_SG_IO_CDB ->do_task(), and emulated ->execute_task() have
all been updated to set se_cmd->scsi_sense_reason and return errno codes
universally upon failure.  This includes cmd->scsi_sense_reason assignment
in target_core_alua.c, target_core_pr.c and target_core_cdb.c emulation code.

Finally it updates fabric modules to remove the legacy usage, and for
TFO->new_cmd_map() callers forwards return values outside of fabric code.
iscsi-target has also been updated to remove a handful of special cases
related to the cleanup and signaling QUEUE_FULL handling w/ ft_write_pending()

(v2: Drop extra SCF_SCSI_CDB_EXCEPTION check during failure from
     transport_generic_new_cmd, and re-add missing task->task_error_status
     assignment in transport_complete_task)

Cc: Christoph Hellwig <hch@lst.de>
Cc: stable@kernel.org
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
2011-12-06 06:00:49 +00:00
Linus Torvalds
32aaeffbd4 Merge branch 'modsplit-Oct31_2011' of git://git.kernel.org/pub/scm/linux/kernel/git/paulg/linux
* 'modsplit-Oct31_2011' of git://git.kernel.org/pub/scm/linux/kernel/git/paulg/linux: (230 commits)
  Revert "tracing: Include module.h in define_trace.h"
  irq: don't put module.h into irq.h for tracking irqgen modules.
  bluetooth: macroize two small inlines to avoid module.h
  ip_vs.h: fix implicit use of module_get/module_put from module.h
  nf_conntrack.h: fix up fallout from implicit moduleparam.h presence
  include: replace linux/module.h with "struct module" wherever possible
  include: convert various register fcns to macros to avoid include chaining
  crypto.h: remove unused crypto_tfm_alg_modname() inline
  uwb.h: fix implicit use of asm/page.h for PAGE_SIZE
  pm_runtime.h: explicitly requires notifier.h
  linux/dmaengine.h: fix implicit use of bitmap.h and asm/page.h
  miscdevice.h: fix up implicit use of lists and types
  stop_machine.h: fix implicit use of smp.h for smp_processor_id
  of: fix implicit use of errno.h in include/linux/of.h
  of_platform.h: delete needless include <linux/module.h>
  acpi: remove module.h include from platform/aclinux.h
  miscdevice.h: delete unnecessary inclusion of module.h
  device_cgroup.h: delete needless include <linux/module.h>
  net: sch_generic remove redundant use of <linux/module.h>
  net: inet_timewait_sock doesnt need <linux/module.h>
  ...

Fix up trivial conflicts (other header files, and  removal of the ab3550 mfd driver) in
 - drivers/media/dvb/frontends/dibx000_common.c
 - drivers/media/video/{mt9m111.c,ov6650.c}
 - drivers/mfd/ab3550-core.c
 - include/linux/dmaengine.h
2011-11-06 19:44:47 -08:00