Commit Graph

218 Commits

Author SHA1 Message Date
Christoph Hellwig d29a5b6acc target: remove SCF_EMULATE_CDB_ASYNC
All ->execute_task instances now need to complete the I/O explicitly,
which can either happen synchronously or asynchronously.

Note that a lot of the CDB emulations appear to return success even if
some lowlevel operations failed.  Given that this is an existing issue
this patch doesn't change that fact.

(nab: Adding missing switch breaks in PR-IN + PR_OUT)

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
2011-11-04 10:43:35 +00:00
Christoph Hellwig e76a35d6c8 target: pass the se_task to the CDB emulation callback
We want to be able to handle all CDBs through it and remove hacks like
always using the first task in a CDB in target_report_luns.

Also rename the callback to ->execute_task to better describe its use.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
2011-11-04 08:00:17 +00:00
Nicholas Bellinger a17f091d1a target: Add generic active I/O shutdown logic
This patch adds the initial pieces of generic active I/O shutdown logic.
This is intended to be a 'opt-in' feature for fabric modules that
includes the following functions to provide a mechinism for fabric
modules to track se_cmd via se_session->sess_cmd_list:

*) target_get_sess_cmd() - Add se_cmd to sess->sess_cmd_list, called
   from fabric module incoming I/O path.
*) target_put_sess_cmd() - Check for completion or drop se_cmd from
   ->sess_cmd_list
*) target_splice_sess_cmd_list() - Splice active I/O list from
   ->sess_cmd_list to ->sess_wait_list, can called with HW fabric
   lock held.
*) target_wait_for_sess_cmds() - Walk ->sess_wait_list waiting on
   individual ->cmd_wait_comp.  Optional transport_wait_for_tasks()
   call.

target_splice_sess_cmd_list() is allowed to be called under HW fabric
lock, and performs the splice into se_sess->sess_wait_list and set
se_cmd->cmd_wait_set.  Then target_wait_for_sess_cmds() walks the list
waiting for individual target_put_sess_cmd() fabric callbacks to
complete.

It also adds TFO->check_release_cmd() to split the completion and memory
release calls, where a fabric module uses target_put_sess_cmd() to check
for I/O completion during session shutdown.  This is currently pushed out
into fabric modules as current fabric code may sleep here waiting for
TFO->check_stop_free() to complete in main response path, and because
target_wait_for_sess_cmds() calling TFO->release_cmd() to free fabric
descriptor memory directly.

Cc: Christoph Hellwig <hch@lst.de>
Cc: Roland Dreier <roland@purestorage.com>
Signed-off-by: Nicholas A. Bellinger <nab@linux-iscsi.org>
2011-11-04 07:50:26 +00:00
Nicholas Bellinger 3151d069e9 target: Remove core TRANSPORT_FREE_CMD_INTR usage
This patch drops TRANSPORT_FREE_CMD_INTR usage from target core, which
includes the removal of transport_generic_free_cmd_intr() symbol,
TRANSPORT_FREE_CMD_INTR usage in transport_processing_thread(), and
special case LUN_RESET handling to skip TRANSPORT_FREE_CMD_INTR processing
in core_tmr_drain_cmd_list().  We now expect that fabric modules will
use an internal workqueue to provide process context when releasing
se_cmd descriptor resources via transport_generic_free_cmd().

Reported-by: Christoph Hellwig <hch@lst.de>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Roland Dreier <roland@purestorage.com>
Cc: Madhuranath Iyengar <mni@risingtidesystems.com>
Signed-off-by: Nicholas Bellinger <nab@risingtidesystems.com>
2011-11-02 15:58:46 +00:00
Nicholas Bellinger 88dd9e26d6 target: Make TFO->check_stop_free return free status
This patch converts target_core_fabric_ops->check_stop_free() usage in
transport_cmd_check_stop() and associated fabric module usage to
return '1' when the passed se_cmd has been released directly within
->check_stop_free(), or return '0' when the passed se_cmd has not
been released.

This addresses an issue where transport_cmd_finish_abort() ->
transport_cmd_check_stop_to_fabric() was leaking descriptors during
LUN_RESET for modules using ->check_stop_free(), but not directly
releasing se_cmd in all cases.

Cc: stable@kernel.org
Signed-off-by: Nicholas Bellinger <nab@risingtidesystems.com>
2011-11-02 15:58:30 +00:00
Linus Torvalds 59e5253417 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial: (59 commits)
  MAINTAINERS: linux-m32r is moderated for non-subscribers
  linux@lists.openrisc.net is moderated for non-subscribers
  Drop default from "DM365 codec select" choice
  parisc: Kconfig: cleanup Kernel page size default
  Kconfig: remove redundant CONFIG_ prefix on two symbols
  cris: remove arch/cris/arch-v32/lib/nand_init.S
  microblaze: add missing CONFIG_ prefixes
  h8300: drop puzzling Kconfig dependencies
  MAINTAINERS: microblaze-uclinux@itee.uq.edu.au is moderated for non-subscribers
  tty: drop superfluous dependency in Kconfig
  ARM: mxc: fix Kconfig typo 'i.MX51'
  Fix file references in Kconfig files
  aic7xxx: fix Kconfig references to READMEs
  Fix file references in drivers/ide/
  thinkpad_acpi: Fix printk typo 'bluestooth'
  bcmring: drop commented out line in Kconfig
  btmrvl_sdio: fix typo 'btmrvl_sdio_sd6888'
  doc: raw1394: Trivial typo fix
  CIFS: Don't free volume_info->UNC until we are entirely done with it.
  treewide: Correct spelling of successfully in comments
  ...
2011-10-25 12:11:02 +02:00
Nicholas Bellinger 2e982ab92d target: Remove legacy se_task->task_timer and associated logic
This patch removes the legacy usage of se_task->task_timer and associated
infrastructure that originally was used as a way to help manage buggy backend
SCSI LLDs that in certain cases would never return back an outstanding task.

This includes the removal of target_complete_timeout_work(), timeout logic
from transport_complete_task(), transport_task_timeout_handler(),
transport_start_task_timer(), the per device task_timeout configfs attribute,
and all task_timeout associated structure members and defines in
target_core_base.h

This is being removed in preparation to make transport_complete_task() run
in lock-less mode.

Cc: Christoph Hellwig <hch@lst.de>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
2011-10-24 03:22:08 +00:00
Nicholas Bellinger 415a090ade target: Fix incorrect transport_sent usage
This patch converts target-core to use se_cmd->t_transport_sent instead of
a duplicated se_cmd->transport_sent member in a handful of locations.
It also updates iscsi_target to properly use ->t_transport_sent instead of
it's own iscsi_cmd_t->transport_sent value that was not being assigned.

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 03:22:06 +00:00
Christoph Hellwig 7c1c6af37a target: remove the task_sg_bidi field se_task and pSCSI BIDI support
This field is never used given that BIDI handling happens at the
command and not the task level.  Remove it and the dead code in
pscsi that tries to work on it.

It also prevents pSCSI passthrough for the two currently enabled BIDI
commands now that task->task_sg_bidi support has been removed.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Cc: Boaz Harrosh <bharrosh@panasas.com>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
2011-10-24 03:21:56 +00:00
Nicholas Bellinger dbc5623eb2 target: transport_subsystem_check_init cleanups
Remove the now unnecessary extra call to transport_subsystem_check_init() in
target_core_register_fabric(), and also merge transport_subsystem_reqmods()
directly into transport_subsystem_check_init().

Reported-by: Christoph Hellwig <hch@infradead.org>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
2011-10-24 03:21:54 +00:00
Christoph Hellwig 35e0e75753 target: use a workqueue for I/O completions
Instead of abusing the target processing thread for offloading I/O
completion in the backends to user context add a new workqueue.  This means
completions can be processed as fast as available CPU time allows it,
including in parallel with other completions and more importantly I/O
submission or QUEUE FULL retries.  This should give much better performance
especially on loaded systems.

As a fallout we can merge all the completed states into a single
one.

On the downside this change complicates lun reset handling a bit by
requiring us to cancel a work item only for those states that have it
initialized.  The alternative would be to either always initialize the work
item to a dummy handler, or always use the same handler and do a switch on
the state. The long term solution will be a flag that says that the command
has an initialized work item, but that's only going to be useful once we
have more users.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
2011-10-24 03:21:52 +00:00
Christoph Hellwig 59aaad1ec4 target: remove unused TRANSPORT_ states
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
2011-10-24 03:21:51 +00:00
Christoph Hellwig f2da9dbdb5 target: remove TRANSPORT_DEFERRED_CMD state
We never check for this state, and it makes testing for a completed
state much harder given that it overrides the existing state.

Also remove the unused deferred_t_state which is related to it.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
2011-10-24 03:21:49 +00:00
Christoph Hellwig bfaf40ada2 target: remove the TRANSPORT_REMOVE state
We never queue an command with this state, and only set it in a completely
bogus place in tcm_fc.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
2011-10-24 03:21:47 +00:00
Christoph Hellwig cc5d0f0f61 target: stop task timers earlier
Currently we stop the timers for all tasks in a command fairly late during
I/O completion, which is fairly pointless and requires all kinds of safety
checks.

Instead delete pending timers early on in transport_complete_task, thus
ensuring no new timers firest after that.  We take t_state_lock a bit later
in that function thus making sure currenly running timers are out of the
criticial section.  To be completely sure the timer has finished we also
add another del_timer_sync call when freeing the task.

This also allows removing TF_TIMER_RUNNING as it would be equivalent
to TF_ACTIVE now.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
2011-10-24 03:21:44 +00:00
Christoph Hellwig e99d48a62b target: remove TF_TIMER_STOP
TF_TIMER_STOP is useless as it only helps to mitigate a tiny race during
deleting the timer.  But given that we have cleared TF_ACTIVE at this point
we already have another mitigation a few lines down the function.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
2011-10-24 03:21:42 +00:00
Christoph Hellwig cdbb70bb4c target: factor some duplicate code for stopping a task
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
2011-10-24 03:21:41 +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 f55918fa32 target: clean up the backend interface to caching parameters
Remove the dpo_emulated, fua_write_emulated, fua_read_emulated and
write_cache_emulated methods, and replace them with a simple bitfields in
se_subsystem_api in those cases where they ever returned one.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
2011-10-24 03:21:31 +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 3189b067ee target: pack struct se_task more tightly
Rearrange the fields in se_task to avoid holes.  Also increase the
flags field to 16 bits as we have the space for it, and this makes
adding new flags safer.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
2011-10-24 03:21:10 +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 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
Roland Dreier dd503a5fcc target: Have core_tmr_alloc_req() take an explicit GFP_xxx flag
Testing in_interrupt() to know when sleeping is allowed is not really
reliable (since eg it won't be true if the caller is holding a spinlock).
Instead have the caller tell core_tmr_alloc_req() what GFP_xxx to use;
every caller except tcm_qla2xxx can use GFP_KERNEL.

Signed-off-by: Roland Dreier <roland@purestorage.com>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
2011-10-24 03:20:53 +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 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 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
Paul Bolle 395cf9691d doc: fix broken references
There are numerous broken references to Documentation files (in other
Documentation files, in comments, etc.). These broken references are
caused by typo's in the references, and by renames or removals of the
Documentation files. Some broken references are simply odd.

Fix these broken references, sometimes by dropping the irrelevant text
they were part of.

Signed-off-by: Paul Bolle <pebolle@tiscali.nl>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
2011-09-27 18:08:04 +02:00
Nicholas Bellinger 052605c6ca target: Make standard INQUIRY return 'not connected' for tpg_virt_lun0
This patch changes target_emulate_inquiry_std() to set the 'not connected'
(0x35) bit in standard INQUIRY response data when we are processing a
request to a virtual LUN=0 mapping from struct se_device *g_lun0_dev that
have been setup for us in transport_lookup_cmd_lun().

This addresses an issue where qla2xxx FC clients need to be able
to create demo-mode I_T FC Nexuses by default, but should not be
exposing the default set of TPG LUNs to all FC clients.  This includes
adding an new optional target_core_fabric_ops->tpg_check_demo_mode_login_only()
caller to allow demo_mode nexuses to skip the old default of bulding
a demo-mode MappedLUNs list via core_tpg_add_node_to_devs().

(roland: Add missing tpg_check_demo_mode_login_only check in core_dev_add_lun)

Reported-by: Roland Dreier <roland@purestorage.com>
Cc: Andrew Vasquez <andrew.vasquez@qlogic.com>
Signed-off-by: Nicholas Bellinger <nab@risingtidesystems.com>
2011-08-22 19:25:35 +00:00
Nicholas Bellinger fa49515956 target: Bump version to v4.1.0-rc1-ml
This patch bumps the target core version to v4.1.0-rc1 now that we are
in sync with upstream lio-core-2.6.git/master

Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
2011-07-22 09:37:49 +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 5de619a31d target: Update QUEUE ALGORITHM MODIFIER control page default
This patch adds the default 'Unrestricted reordering allowed' for SCSI
control mode page QUEUE ALGORITHM MODIFIER on a per se_device basis in
target_modesense_control() following spc4r23.  This includes a new
emuluate_rest_reord configfs attribute that currently (only) accepts
zero to signal 'Unrestricted reordering allowed' in control mode page
usage by the backend target device.

Reported-by: Roland Dreier <roland@purestorage.com>
Signed-off-by: Nicholas Bellinger <nab@risingtidesystems.com>
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
Roland Dreier e22a7f0752 target: Implement Block Device Characteristics VPD page
Implement page B1h, Block Device Characteristics, so that we can report
a medium rotation rate of 1 (non-rotating / solid state) if the
is_nonrot device attribute is set; we update the iblock backend to set
this attribute if the underlying Linux block device has its nonrot
flag set.

Signed-off-by: Roland Dreier <roland@purestorage.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
2011-07-22 09:37:47 +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
Christoph Hellwig db1620a278 target: remove the unused SCF_* flags
This patch contains a squashed version to remove unused  SCF_* flags:

target: remove the unused SCF_SE_DISABLE_ONLINE_CHECK flag
target: remove the unused SCF_CMD_PASSTHROUGH_NOALLOC flag
target: remove the unused SCF_EMULATE_SYNC_UNMAP flag
target: remove the unused SCF_EMULATE_SYNC_CACHE flag

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
Christoph Hellwig dc2e652d5f target: remove the always-noop ->new_cmd_failure method
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
Andy Grover a1d8b49abd target: Updates from AGrover and HCH (round 3)
This patch contains a squashed version of third round series cleanups,
improvements ,and simplfications from Andy and Christoph ahead of the
heavy lifting between round 3 -> 4 for the target core SGL conversion.

This include cleanups to the main target I/O path and other miscellaneous
updates.

target: Replace custom sg<->buf functions with lib funcs
target: Simplify sector limiting code
target: get_cdb should never return NULL
target: Simplify transport_memcpy_se_mem_read_contig
target: Use assignment rather than increment for t_task_cdbs
target: Don't pass dma_size to generic_get_mem
target: Pass sg with type scatterlist in transport_map_sg_to_mem
target: Move task_sg_num next to task_sg in struct se_task
target: inline struct se_transport_task into struct se_cmd
target: Change name & semantics of transport_get_sectors()
target: Remove unused members of se_cmd
target: Rename se_cmd.t_task_cdbs to t_task_list_num
target: Fix some spelling
target: Remove unused var from transport_generic_do_tmr
target: map_sg_to_mem: return sg_count in return value
target/pscsi: Use min_t for sector limits
target/pscsi: Unused param for pscsi_get_bio()
target: Rename get_cdb_count to allocate_tasks
target: Make transport_generic_new_cmd() available for iscsi-target
target: Remove fabric callback to allocate iovecs
target: Fix transport_generic_new_cmd WRITE comment

(hch: Use __GFP_ZERO usage for alloc_pages() usage)

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 09:37:44 +00:00
Andy Grover 5951146dea target: More core cleanups from AGrover (round 2)
This patch contains the squashed version of second round of target core
cleanups and simplifications and Andy and Co.   It also contains a handful
of fixes to address bugs the original series and other minor cleanups.

Here is the condensed shortlog:

target: Remove unneeded casts to void*
target: Rename get_lun_for_{cmd,tmr} to lookup_{cmd,tmr}_lun
target: Make t_task a member of se_cmd, not a pointer
target: Handle functions returning "-2"
target: Use cmd->se_dev over cmd->se_lun->lun_se_dev
target: Embed qr in struct se_cmd
target: Replace embedded struct se_queue_req with a list_head
target: Rename list_heads that are nodes in struct se_cmd to "*_node"
target: Fold transport_device_setup_cmd() into lookup_{tmr,cmd}_lun()
target: Make t_mem_list and t_mem_list_bidi members of t_task
target: Add comment & cleanup transport_map_sg_to_mem()
target: Remove unneeded checks in transport_free_pages()

(Roland: Fix se_queue_req removal leftovers OOPs)
(nab: Fix transport_lookup_tmr_lun failure case)
(nab: Fix list_empty(&cmd->t_task.t_mem_bidi_list) inversion bugs)

Signed-off-by: Andy Grover <agrover@redhat.com>
Signed-off-by: Roland Dreier <roland@purestorage.com>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
2011-07-22 09:37:43 +00:00
Andy Grover e3d6f909ed target: Core cleanups from AGrover (round 1)
This patch contains the squashed version of a number of cleanups and
minor fixes from Andy's initial series (round 1) for target core this
past spring.  The condensed log looks like:

target: use errno values instead of returning -1 for everything
target: Rename transport_calc_sg_num to transport_init_task_sg
target: Fix leak in error path in transport_init_task_sg
target/pscsi: Remove pscsi_get_sh() usage
target: Make two runtime checks into WARN_ONs
target: Remove hba queue depth and convert to spin_lock_irq usage
target: dev->dev_status_queue_obj is unused
target: Make struct se_queue_req.cmd type struct se_cmd *
target: Remove __transport_get_qr_from_queue()
target: Rename se_dev->g_se_dev_list to se_dev_node
target: Remove struct se_global
target: Simplify scsi mib index table code
target: Make dev_queue_obj a member of se_device instead of a pointer
target: remove extraneous returns at end of void functions
target: Ensure transport_dump_vpd_ident_type returns null-terminated str
target: Function pointers don't need to use '&' to be assigned
target: Fix comment in __transport_execute_tasks()
target: Misc style cleanups
target: rename struct pr_reservation_template to pr_reservation
target: Remove #defines that just perform indirection
target: Inline transport_get_task_from_execute_queue()
target: Minor header comment fixes

Signed-off-by: Andy Grover <agrover@redhat.com>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
2011-07-22 09:37:43 +00:00
Nicholas Bellinger efa4988d72 target: Remove unnecessary *cdb transport_get_lun_for_cmd parameter
This patch removes the now unnecessary 'unsigned char *cdb' function
parameter from transport_get_lun_for_cmd().  This also includes updating
lio-target, tcm_loop and tcm_fc usage of transport_get_lun_for_cmd().

Reported-by: Fubo Chen <fubo.chen@gmail.com>
Signed-off-by: Nicholas A. Bellinger <nab@linux-iscsi.org>
2011-07-22 09:37:42 +00:00
Nicholas Bellinger d60b7a0fc9 [SCSI] target: Convert REPORT_LUNs to use int_to_scsilun
This patch converts transport_core_report_lun_response() to use
drivers/scsi/scsi_scan.c:int_to_scsilun instead of using the
struct target_core_fabric_ops->pack_lun() fabric provided API vector.

It also removes the tfo->pack_lun check from target_fabric_tf_ops_check()
and removes from struct target_core_fabric_ops->pack_lun() from
target_core_fabric_ops.h, and the following mainline scsi-misc fabric
modules:

*) tcm_loop: Drop tcm_loop_pack_lun() usage
*) tcm_fc: Drop ft_pack_lun() usage

Reported-by: Mike Christie <michaelc@cs.wisc.edu>
Signed-off-by: Nicholas A. Bellinger <nab@linux-iscsi.org>
Signed-off-by: James Bottomley <jbottomley@parallels.com>
2011-05-24 13:02:42 -04:00
Nicholas Bellinger f436677262 [SCSI] target: Fix bug with task_sg chained transport_free_dev_tasks release
This patch addresses a bug in the target core release path for HW
operation where transport_free_dev_tasks() was incorrectly being called
from transport_lun_remove_cmd() while releasing a se_cmd reference and
calling struct target_core_fabric_ops->queue_data_in().

This would result in a OOPs with HW target mode when the release of
se_task->task_sg[] would happen before pci_unmap_sg() can be called in
HW target mode fabric module code.  This patch addresses the issue by
moving transport_free_dev_tasks() from transport_lun_remove_cmd() into
transport_generic_free_cmd(), and adding TRANSPORT_FREE_CMD_INTR and
transport_generic_free_cmd_intr() to allow se_cmd descriptor release
to happen fromfrom within transport_processing_thread() process context
when release of se_cmd is not possible from HW interrupt context.

Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
Cc: stable@kernel.org
Signed-off-by: James Bottomley <jbottomley@parallels.com>
2011-05-24 13:00:10 -04:00
Lucas De Marchi 25985edced Fix common misspellings
Fixes generated by 'codespell' and manually reviewed.

Signed-off-by: Lucas De Marchi <lucas.demarchi@profusion.mobi>
2011-03-31 11:26:23 -03:00
Nicholas Bellinger 12d2338429 [SCSI] target: add initial statistics
This patch adds a target_core_mib.c statistics conversion for
backend context struct se_subsystem_dev + struct se_device config_group
based statistics in target_core_device.c using CONFIGFS_EATTR()
based struct config_item_types from target_core_stat.c code.

The conversion from backend /proc/scsi_target/mib/ context output to configfs
default groups+attributes include scsi_dev, scsi_lu, and scsi_tgt_dev output
from within individual:

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

The legacy procfs output now appear as individual configfs attributes under:

*) $HBA/$DEV/statistics/scsi_dev:

|-- indx
|-- inst
|-- ports
`-- role

*) $HBA/$DEV/statistics/scsi_lu:

|-- creation_time
|-- dev
|-- dev_type
|-- full_stat
|-- hs_num_cmds
|-- indx
|-- inst
|-- lu_name
|-- lun
|-- num_cmds
|-- prod
|-- read_mbytes
|-- resets
|-- rev
|-- state_bit
|-- status
|-- vend
`-- write_mbytes

*) $HBA/$DEV/statistics/scsi_tgt_dev:

|-- indx
|-- inst
|-- non_access_lus
|-- num_lus
|-- resets
`-- status

The conversion from backend /proc/scsi_target/mib/ context output to configfs
default groups+attributes include scsi_port, scsi_tgt_port and scsi_transport
output from within individual:

	/sys/kernel/config/target/fabric/$WWN/tpgt_$TPGT/lun/lun_$LUN_ID/statistics/

The legacy procfs output now appear as individual configfs attributes under:

*) fabric/$WWN/tpgt_$TPGT/lun/lun_$LUN_ID/statistics/scsi_port

|-- busy_count
|-- dev
|-- indx
|-- inst
`-- role

*) fabric/$WWN/tpgt_$TPGT/lun/lun_$LUN_ID/statistics/scsi_tgt_port

|-- dev
|-- hs_in_cmds
|-- in_cmds
|-- indx
|-- inst
|-- name
|-- port_index
|-- read_mbytes
`-- write_mbytes

*) fabric/$WWN/tpgt_$TPGT/lun/lun_$LUN_ID/statistics/scsi_transport

|-- dev_name
|-- device
|-- indx
`-- inst

The conversion from backend /proc/scsi_target/mib/ context output to configfs
default groups+attributes include scsi_att_intr_port and scsi_auth_intr output
from within individual:

	/sys/kernel/config/target/fabric/$WWN/tpgt_$TPGT/acls/$INITIATOR_WWN/lun_$LUN_ID/statistics/

The legacy procfs output now appear as individual configfs attributes under:

*) acls/$INITIATOR_WWN/lun_$LUN_ID/statistics/scsi_att_intr_port

|-- dev
|-- indx
|-- inst
|-- port
|-- port_auth_indx
`-- port_ident

*) acls/$INITIATOR_WWN/lun_$LUN_ID/statistics/scsi_auth_intr

|-- att_count
|-- creation_time
|-- dev
|-- dev_or_port
|-- hs_num_cmds
|-- indx
|-- inst
|-- intr_name
|-- map_indx
|-- num_cmds
|-- port
|-- read_mbytes
|-- row_status
`-- write_mbytes

Also, this includes adding struct target_fabric_configfs_template->
tfc_wwn_fabric_stats_cit and ->tfc_tpg_nacl_stat_cit respectively for
use during target_core_fabric_configfs.c:target_fabric_setup_cits()

Signed-off-by: Nicholas A. Bellinger <nab@linux-iscsi.org>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>
2011-03-23 11:36:50 -05:00
Nicholas Bellinger 15fb48cc40 [SCSI] target: update version to v4.0.0-rc7-ml
Signed-off-by: Nicholas A. Bellinger <nab@linux-iscsi.org>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>
2011-03-23 11:36:49 -05:00
Nicholas Bellinger 5c6cd61319 [SCSI] target: Convert TMR REQ/RSP definitions to target namespace
This patch changes include/target/target_core_tmr.h code to use
target specific 'TMR_*' prefixed definitions for fabric independent
SCSI Task Management Request/Request naming in include/scsi/scsi.h
definitions for mainline target code.

Signed-off-by: Nicholas A. Bellinger <nab@linux-iscsi.org>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>
2011-03-23 11:36:35 -05:00
Nicholas Bellinger 35ce9e26d7 [SCSI] target: Remove spurious double cast from structure macro accessors
Reported-by: Fubo Chen <fubo.chen@gmail.com>
Cc: James Bottomley <James.Bottomley@suse.de>
Signed-off-by: Nicholas A. Bellinger <nab@linux-iscsi.org>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>
2011-03-23 11:36:32 -05:00
Dan Carpenter 5dd7ed2e81 [SCSI] target: Minor sparse warning fixes and annotations
This patch addresses the majority of sparse warnings and adds
proper locking annotations.  It also fixes the dubious one-bit signed
bitfield, for which the signed one-bit types can be 0 or -1 which can
cause a problem if someone ever checks if (foo->lu_gp_assoc == 1).
The current code is fine because everyone just checks zero vs non-zero.
But Sparse complains about it so lets change it.  The warnings look like
this:

include/target/target_core_base.h:228:26: error: dubious one-bit signed bitfield

Signed-off-by: Dan Carpenter <error27@gmail.com>
Signed-off-by: Fubo Chen <fubo.chen@gmail.com>
Signed-off-by: Nicholas A. Bellinger <nab@linux-iscsi.org>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>
2011-03-23 11:36:29 -05:00
Nicholas Bellinger 52208ae3fc [SCSI] target: Fix t_transport_aborted handling in LUN_RESET + active I/O shutdown
This patch addresses two outstanding bugs related to
T_TASK(cmd)->t_transport_aborted handling during TMR LUN_RESET and
active I/O shutdown.

This first involves adding two explict t_transport_aborted=1
assignments in core_tmr_lun_reset() in order to signal the task has
been aborted, and updating transport_generic_wait_for_tasks() to skip
sleeping when t_transport_aborted=1 has been set.  This fixes an issue
where transport_generic_wait_for_tasks() would end up sleeping
indefinately when called from fabric module context while TMR
LUN_RESET was happening with long outstanding backend struct se_task
not yet being completed.

The second adds a missing call to
transport_remove_task_from_execute_queue() when
task->task_execute_queue=1 is set in order to fix an OOPs when
task->t_execute_list has not been dropped.  It also fixes the same
case in transport_processing_shutdown() to prevent the issue from
happening during active I/O struct se_device shutdown.

Signed-off-by: Nicholas A. Bellinger <nab@linux-iscsi.org>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>
2011-02-28 11:23:32 -06:00
Nicholas Bellinger 1f6fe7cba1 [SCSI] target: fix use after free detected by SLUB poison
This patch moves a large number of memory release paths inside of the
configfs callback target_core_hba_item_ops->release() called from
within fs/configfs/item.c: config_item_cleanup() context.  This patch
resolves the SLUB 'Poison overwritten' warnings.

Signed-off-by: Nicholas A. Bellinger <nab@linux-iscsi.org>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>
2011-02-12 12:32:41 -06:00
Nicholas Bellinger e89d15eead [SCSI] target: Remove procfs based target_core_mib.c code
This patch removes the legacy procfs based target_core_mib.c code,
and moves the necessary scsi_index_tables functions and defines into
target_core_transport.c and target_core_base.h code to allow existing
fabric independent statistics to function.

This includes the removal of a handful of 'atomic_t mib_ref_count'
counters used in struct se_node_acl, se_session and se_hba to prevent
removal while using seq_list procfs walking logic.

[jejb: fix up compile failures]
Signed-off-by: Nicholas A. Bellinger <nab@linux-iscsi.org>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>
2011-02-12 12:15:47 -06:00
Nicholas Bellinger c66ac9db8d [SCSI] target: Add LIO target core v4.0.0-rc6
LIO target is a full featured in-kernel target framework with the
following feature set:

High-performance, non-blocking, multithreaded architecture with SIMD
support.

Advanced SCSI feature set:

    * Persistent Reservations (PRs)
    * Asymmetric Logical Unit Assignment (ALUA)
    * Protocol and intra-nexus multiplexing, load-balancing and failover (MC/S)
    * Full Error Recovery (ERL=0,1,2)
    * Active/active task migration and session continuation (ERL=2)
    * Thin LUN provisioning (UNMAP and WRITE_SAMExx)

Multiprotocol target plugins

Storage media independence:

    * Virtualization of all storage media; transparent mapping of IO to LUNs
    * No hard limits on number of LUNs per Target; maximum LUN size ~750 TB
    * Backstores: SATA, SAS, SCSI, BluRay, DVD, FLASH, USB, ramdisk, etc.

Standards compliance:

    * Full compliance with IETF (RFC 3720)
    * Full implementation of SPC-4 PRs and ALUA

Significant code cleanups done by Christoph Hellwig.

[jejb: fix up for new block bdev exclusive interface. Minor fixes from
 Randy Dunlap and Dan Carpenter.]
Signed-off-by: Nicholas A. Bellinger <nab@linux-iscsi.org>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>
2011-01-14 10:12:29 -06:00