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2011-11-06Merge branch 'modsplit-Oct31_2011' of ↵Linus Torvalds
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
2011-11-06Merge branch 'for-next' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/nab/target-pending * 'for-next' of git://git.kernel.org/pub/scm/linux/kernel/git/nab/target-pending: target: use ->exectute_task for all CDB emulation target: remove SCF_EMULATE_CDB_ASYNC target: refactor transport_emulate_control_cdb target: pass the se_task to the CDB emulation callback target: split core_scsi3_emulate_pr target: split core_scsi2_emulate_crh target: Add generic active I/O shutdown logic target: add back error handling in transport_complete_task target/pscsi: blk_make_request() returns an ERR_PTR() target: Remove core TRANSPORT_FREE_CMD_INTR usage target: Make TFO->check_stop_free return free status iscsi-target: Fix non-immediate TMR handling iscsi-target: Add missing CMDSN_LOWER_THAN_EXP check in iscsit_handle_scsi_cmd target: Avoid double list_del for aborted se_tmr_req target: Minor cleanups to core_tmr_drain_tmr_list target: Fix wrong se_tmr being added to drain_tmr_list target: Fix incorrect se_cmd assignment in core_tmr_drain_tmr_list target: Check -ENOMEM to signal QUEUE_FULL from fabric callbacks tcm_loop: Add explict read buffer memset for SCF_SCSI_CONTROL_SG_IO_CDB target: Fix compile warning w/ missing module.h include
2011-11-04target: use ->exectute_task for all CDB emulationChristoph Hellwig
Instead of calling into transport_emulate_control_cdb from __transport_execute_tasks for some CDBs always set up ->exectute_tasks in the command sequence and use it uniformly. (nab: Add default passthrough break for SERVICE_ACTION_IN) Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
2011-11-04target: remove SCF_EMULATE_CDB_ASYNCChristoph Hellwig
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>
2011-11-04target: refactor transport_emulate_control_cdbChristoph Hellwig
Encapsulate each CDB emulation into a function of its own, to prepare setting ->exectute_task to these routines. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
2011-11-04target: pass the se_task to the CDB emulation callbackChristoph Hellwig
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>
2011-11-04target: split core_scsi3_emulate_prChristoph Hellwig
Split core_scsi2_emulate_crh into one routine each for the PERSISTENT_RESERVE_IN and PERSISTENT_RESERVE_OUT side. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
2011-11-04target: split core_scsi2_emulate_crhChristoph Hellwig
Split core_scsi2_emulate_crh into one routine each for the reserve and release side. The common code now is in a helper called by both routines. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
2011-11-04target: Add generic active I/O shutdown logicNicholas Bellinger
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>
2011-11-02target: add back error handling in transport_complete_taskChristoph Hellwig
The commit target: use a workqueue for I/O completions accidentally removed setting t_tasks_failed in transport_complete_task. Add it back in a slightly cleaner way; now it is set for every failed task instead of special casing the last one completing by using the success argument directly for it. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Nicholas A. Bellinger <nab@linux-iscsi.org>
2011-11-02target/pscsi: blk_make_request() returns an ERR_PTR()Dan Carpenter
The check is wrong here because blk_make_request() returns an ERR_PTR() and it doesn't return NULL. Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com> Signed-off-by: Nicholas A. Bellinger <nab@linux-iscsi.org>
2011-11-02target: Remove core TRANSPORT_FREE_CMD_INTR usageNicholas Bellinger
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>
2011-11-02target: Make TFO->check_stop_free return free statusNicholas Bellinger
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>
2011-11-02iscsi-target: Fix non-immediate TMR handlingNicholas Bellinger
This patch addresses two issues with non immediate TMR handling in iscsit_handle_task_mgt_cmd(). The first involves breakage due to v3.1-rc conversion of iscsit_sequence_cmd(), which upon good status would hit the iscsit_add_reject_from_cmd() block of code. This patch adds an explict check for CMDSN_ERROR_CANNOT_RECOVER. The second adds a check to return when non immediate TMR operation is detected after iscsit_ack_from_expstatsn(), as iscsit_sequence_cmd() -> iscsit_execute_cmd() will have called transport_generic_handle_tmr() for the non immediate TMR case already. Cc: Andy Grover <agrover@redhat.com> Cc: stable@kernel.org Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
2011-11-02iscsi-target: Add missing CMDSN_LOWER_THAN_EXP check in iscsit_handle_scsi_cmdNicholas Bellinger
This patch adds a missing CMDSN_LOWER_THAN_EXP return check for iscsit_sequence_cmd() in iscsit_handle_scsi_cmd() that was incorrectly dropped during the v3.1-rc cleanups to use iscsit_sequence_cmd(). Cc: Andy Grover <agrover@redhat.com> Cc: stable@kernel.org Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
2011-11-02target: Avoid double list_del for aborted se_tmr_reqJoern Engel
After the list_del() in core_tmr_drain_tmr_list(), core_tmr_release_req() would list_del() the same object again. Call graph: core_tmr_drain_tmr_list transport_cmd_finish_abort_tmr transport_generic_remove transport_free_se_cmd core_tmr_release_req So use list_del_init(), as list_del() of an initialized list_head is safe and essentially a nop. In the CONFIG_DEBUG_LIST case, list_del() actually poisons the list_head, but that is fine as we free the object directly afterwards. Signed-off-by: Joern Engel <joern@logfs.org> Cc: stable@kernel.org Signed-off-by: Nicholas Bellinger <nab@risingtidesystems.com>
2011-10-31drivers/target: Add module.h to drivers/target files as required.Paul Gortmaker
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
2011-10-31drivers/target: Add export.h to files as required.Paul Gortmaker
So that they have access to EXPORT_SYMBOL variants and THIS_MODULE. Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
2011-10-27target: Minor cleanups to core_tmr_drain_tmr_listJoern Engel
This patch adds a handful minor cleanups to core_tmr_drain_tmr_list() that remove an unnecessary NULL check, use list_for_each_entry_safe() instead of list_entry(), and makes the drain_tmr_list walk use *tmr_p instead of directly referencing the passed *tmr function parameter. Signed-off-by: Joern Engel <joern@logfs.org> Cc: Joern Engel <joern@logfs.org> Reviewed-by: Roland Dreier <roland@purestorage.com> Cc: Roland Dreier <roland@purestorage.com> Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
2011-10-27target: Fix wrong se_tmr being added to drain_tmr_listJoern Engel
This patch fixes another bug from LUN_RESET re-org fallout in core_tmr_drain_tmr_list() that was adding the wrong se_tmr_req into the local drain_tmr_list to be walked + released. Signed-off-by: Joern Engel <joern@logfs.org> Cc: Joern Engel <joern@logfs.org> Reviewed-by: Roland Dreier <roland@purestorage.com> Cc: Roland Dreier <roland@purestorage.com> Cc: stable@kernel.org Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
2011-10-27target: Fix incorrect se_cmd assignment in core_tmr_drain_tmr_listJoern Engel
This patch fixes a bug in core_tmr_drain_tmr_list() where drain_tmr_list was using the wrong se_tmr_req for cmd assignment due to a typo during the LUN_RESET re-org. This was resulting in general protection faults while using the leftover bogus *tmr_p pointer from list_for_each_entry_safe(). Signed-off-by: Joern Engel <joern@logfs.org> Cc: Joern Engel <joern@logfs.org> Cc: stable@kernel.org Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
2011-10-27target: Check -ENOMEM to signal QUEUE_FULL from fabric callbacksNicholas Bellinger
This patch changes target core to also check for -ENOMEM from fabric callbacks to signal QUEUE_FULL status, instead of just -EAGAIN in order to catch a larger set of fabric failure cases that want to trigger QUEUE_FULL logic. This includes the callbacks for ->write_pending(), ->queue_data_in() and ->queue_status(). It also makes transport_generic_write_pending() return zero upon QUEUE_FULL, and removes two unnecessary -EAGAIN checks to catch write pending QUEUE_FULL cases from transport_generic_new_cmd() failures in transport_handle_cdb_direct() and transport_processing_thread():TRANSPORT_NEW_CMD_MAP state. Reported-by: Bart Van Assche <bvanassche@acm.org> Cc: Bart Van Assche <bvanassche@acm.org> Cc: Christoph Hellwig <hch@lst.de> Cc: Roland Dreier <roland@purestorage.com> Signed-off-by: Nicholas A. Bellinger <nab@linux-iscsi.org>
2011-10-26tcm_loop: Add explict read buffer memset for SCF_SCSI_CONTROL_SG_IO_CDBNicholas Bellinger
This patch addresses an issue with buggy userspace code sending I/O via scsi-generic that does not explictly clear their associated read buffers. It adds an explict memset of the first SGL entry within tcm_loop_new_cmd_map() for SCF_SCSI_CONTROL_SG_IO_CDB payloads that are currently guaranteed to be a single SGL by target-core code. This issue is a side effect of the v3.1-rc1 merge to remove the extra memcpy between certain control CDB types using a contigious + cleared buffer in target-core, and performing a memcpy into the SGL list within tcm_loop. It was originally mainfesting itself by udev + scsi_id + scsi-generic not properly setting up the expected /dev/disk/by-id/ symlinks because the INQUIRY payload was containing extra bogus data preventing the proper NAA IEEE WWN from being parsed by userspace. 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>
2011-10-26target: Fix compile warning w/ missing module.h includeNicholas Bellinger
This patch fixes the following compile warning in target_core_cdb.c in recent linux-next code due to the new use of EXPORT_SYMBOL() for target_get_task_cdb(). drivers/target/target_core_cdb.c:1316: warning: data definition has no type or storage class drivers/target/target_core_cdb.c:1316: warning: type defaults to ‘int’ in declaration of ‘EXPORT_SYMBOL’ drivers/target/target_core_cdb.c:1316: warning: parameter names (without types) in function declaration Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
2011-10-25Merge branch 'for-linus' of ↵Linus Torvalds
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 ...
2011-10-25Merge branch 'for-next' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/nab/target-pending * 'for-next' of git://git.kernel.org/pub/scm/linux/kernel/git/nab/target-pending: (62 commits) target: Fix compile warning w/ missing module.h include target: Remove legacy se_task->task_timer and associated logic target: Fix incorrect transport_sent usage target: re-use the command S/G list for single-task commands target: Fix BIDI t_task_cdb handling in transport_generic_new_cmd target: remove transport_allocate_tasks target: merge transport_new_cmd_obj into transport_generic_new_cmd target: remove the task_sg_bidi field se_task and pSCSI BIDI support target: transport_subsystem_check_init cleanups target: use a workqueue for I/O completions target: remove unused TRANSPORT_ states target: remove TRANSPORT_DEFERRED_CMD state target: remove the TRANSPORT_REMOVE state target: move depth_left manipulation out of transport_generic_request_failure target: stop task timers earlier target: remove TF_TIMER_STOP target: factor some duplicate code for stopping a task target: fix list walking in transport_free_dev_tasks target: use transport_cmd_check_stop_to_fabric consistently target: do not pass the queue object to transport_remove_cmd_from_queue ...
2011-10-25Merge branch 'next' of git://selinuxproject.org/~jmorris/linux-securityLinus Torvalds
* 'next' of git://selinuxproject.org/~jmorris/linux-security: (95 commits) TOMOYO: Fix incomplete read after seek. Smack: allow to access /smack/access as normal user TOMOYO: Fix unused kernel config option. Smack: fix: invalid length set for the result of /smack/access Smack: compilation fix Smack: fix for /smack/access output, use string instead of byte Smack: domain transition protections (v3) Smack: Provide information for UDS getsockopt(SO_PEERCRED) Smack: Clean up comments Smack: Repair processing of fcntl Smack: Rule list lookup performance Smack: check permissions from user space (v2) TOMOYO: Fix quota and garbage collector. TOMOYO: Remove redundant tasklist_lock. TOMOYO: Fix domain transition failure warning. TOMOYO: Remove tomoyo_policy_memory_lock spinlock. TOMOYO: Simplify garbage collector. TOMOYO: Fix make namespacecheck warnings. target: check hex2bin result encrypted-keys: check hex2bin result ...
2011-10-25target: Fix compile warning w/ missing module.h includeNicholas Bellinger
This patch fixes the following compile warning in target_core_cdb.c in recent linux-next code due to the new use of EXPORT_SYMBOL() for target_get_task_cdb(). drivers/target/target_core_cdb.c:1316: warning: data definition has no type or storage class drivers/target/target_core_cdb.c:1316: warning: type defaults to ‘int’ in declaration of ‘EXPORT_SYMBOL’ drivers/target/target_core_cdb.c:1316: warning: parameter names (without types) in function declaration Cc: Christoph Hellwig <hch@lst.de> Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
2011-10-24target: Remove legacy se_task->task_timer and associated logicNicholas Bellinger
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>
2011-10-24target: Fix incorrect transport_sent usageNicholas Bellinger
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>
2011-10-24target: re-use the command S/G list for single-task commandsChristoph Hellwig
If we only have a single task per command (which at least in my testing is the by far most common case) we do not have to allocate a new per-task S/G list but can reuse the one from the command. (nab: Fix BIDI handling in transport_free_dev_tasks) Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
2011-10-24target: Fix BIDI t_task_cdb handling in transport_generic_new_cmdNicholas Bellinger
This patch fixes a bug for BIDI handling in transport_generic_new_cmd() where cmd->t_task_cdbs_left and Co. where not taking into account the extra task count generated during the first call to transport_allocate_data_tasks(). Cc: Christoph Hellwig <hch@lst.de> Cc: Boaz Harrosh <bharrosh@panasas.com> Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
2011-10-24target: remove transport_allocate_tasksChristoph Hellwig
There were only two callers, and one of them always wants the call to transport_allocate_data_tasks anyway. Also drop the constant lba argument to transport_allocate_data_tasks and move the variables inside it into the minimum required scope. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
2011-10-24target: merge transport_new_cmd_obj into transport_generic_new_cmdChristoph Hellwig
These are two fairly small functions, and merging them gives a much more readable control flow, and opportunities for more useful comments. It also moves all code related to resources allocation closer together and allows to remove a forward declaration for transport_allocate_tasks. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
2011-10-24target: remove the task_sg_bidi field se_task and pSCSI BIDI supportChristoph Hellwig
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>
2011-10-24target: transport_subsystem_check_init cleanupsNicholas Bellinger
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>
2011-10-24target: use a workqueue for I/O completionsChristoph Hellwig
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>
2011-10-24target: remove TRANSPORT_DEFERRED_CMD stateChristoph Hellwig
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>
2011-10-24target: remove the TRANSPORT_REMOVE stateChristoph Hellwig
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>
2011-10-24target: move depth_left manipulation out of transport_generic_request_failureChristoph Hellwig
We only need to decrement dev->depth_left if failing a command from __transport_execute_tasks. Instead of doing it first thing in transport_generic_request_failure and requiring a pseudo-flag argument for it just opencode the decrement in the two callers (which should be factored into a single one anyway) Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
2011-10-24target: stop task timers earlierChristoph Hellwig
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>
2011-10-24target: remove TF_TIMER_STOPChristoph Hellwig
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>
2011-10-24target: factor some duplicate code for stopping a taskChristoph Hellwig
Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
2011-10-24target: fix list walking in transport_free_dev_tasksChristoph Hellwig
list_for_each_entry_safe only protects against deletions from the list, but not against any concurrent modifications. Given that we drop t_state_lock inside the loop it is not safe in transport_free_dev_tasks. Instead of use a local dispose_list that we move all tasks that are to be deleted to. This is safe because we never do list_emptry checks on t_list to check if a command is on the list anywhere. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
2011-10-24target: use transport_cmd_check_stop_to_fabric consistentlyChristoph Hellwig
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>
2011-10-24target: do not pass the queue object to transport_remove_cmd_from_queueChristoph Hellwig
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>
2011-10-24target: remove SCF_EMULATE_QUEUE_FULLChristoph Hellwig
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>
2011-10-24target: remove the transport_qf_callback se_cmd callbackChristoph Hellwig
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>
2011-10-24target: clean up the backend interface to caching parametersChristoph Hellwig
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>
2011-10-24target: make iblock_emulate_sync_cache asynchronousChristoph Hellwig
Do not block the submitting thread when handling a SYNCHRONIZE CACHE command, but implement it asynchronously by sending the FLUSH command ourself and calling transport_complete_sync_cache from the completion handler. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>