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path: root/include/target/target_core_base.h
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2011-12-16target: Set additional sense length field in sense dataRoland Dreier
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>
2011-12-14target: Remove extra se_device->execute_task_lock access in fast pathNicholas Bellinger
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>
2011-12-14target: Drop se_device TCQ queue_depth usage from I/O pathNicholas Bellinger
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>
2011-12-14target: Add target_submit_cmd() for process context fabric submissionNicholas Bellinger
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>
2011-12-14target: Make target_put_sess_cmd use target_release_cmd_krefNicholas Bellinger
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>
2011-12-14target: remove overagressive ____cacheline_aligned annoationsChristoph Hellwig
If we want dynamically allocated objects to be cacheline aligned we need to tell that to the slab allocator by using the proper flags and not by liberally sprinkling annotations onto all structures. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
2011-12-14target: make the se_task task_state_active a normal boolChristoph Hellwig
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>
2011-12-14target: remove the se_task task_error_status fieldChristoph Hellwig
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>
2011-12-14target: fold se_task.task_sense into task_flagsChristoph Hellwig
Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
2011-12-14target: header reshuffle, part2Christoph Hellwig
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>
2011-12-06target: remove the unused se_dev_listChristoph Hellwig
Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
2011-12-06target: remove unused struct fieldsJörn Engel
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>
2011-12-06target: remove the unused t_task_pt_sgl and t_task_pt_sgl_num se_cmd fieldsChristoph Hellwig
Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
2011-12-06target: remove the t_tasks_bidi se_cmd fieldChristoph Hellwig
And use a SCF_BIDI flag instead. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
2011-12-06target: remove the t_tasks_fua se_cmd fieldChristoph Hellwig
And use a SCF_FUA flag instead. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
2011-12-06target: remove the se_ordered_node se_cmd fieldChristoph Hellwig
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>
2011-12-06target: remove the se_obj_ptr and se_orig_obj_ptr se_cmd fieldsChristoph Hellwig
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>
2011-12-06target: Avoid compiler warnings about signed one-bit bitfieldsBart Van Assche
Convert to unsigned bit fields for active I/O shutdown fields. Signed-off-by: Bart Van Assche <bvanassche@acm.org> Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
2011-12-06target: Address legacy PYX_TRANSPORT_* return code breakageNicholas Bellinger
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>
2011-11-04target: 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: 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: 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: 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>
2011-10-24target: 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: 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: 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 unused TRANSPORT_ statesChristoph Hellwig
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: 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: 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: remove the ->transport_split_cdb callback in se_cmdChristoph Hellwig
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>
2011-10-24target: pack struct se_task more tightlyChristoph Hellwig
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>
2011-10-24target: Remove unnecessary se_task membersChristoph Hellwig
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>
2011-10-24target: make more use of the task_flags field in se_taskChristoph Hellwig
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>
2011-10-24target: Cleanup unused se_task bitsChristoph Hellwig
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>
2011-10-24target: Cleanup unused target_core_base.h bitsChristoph Hellwig
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>
2011-10-24target: Convert ->transport_wait_for_tasks usage to transport_generic_free_cmdNicholas Bellinger
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>
2011-10-24target: Remove session_reinstatement parameter from ->transport_wait_for_tasksNicholas Bellinger
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>
2011-07-22target: Bump version to v4.1.0-rc1-mlNicholas Bellinger
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>
2011-07-22target: Update QUEUE ALGORITHM MODIFIER control page defaultNicholas Bellinger
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>
2011-07-22target: Follow up core updates from AGrover and HCH (round 4)Andy Grover
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>
2011-07-22target: Eliminate usage of struct se_memAndy Grover
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>
2011-07-22target: Pass 2nd param of transport_split_cdb by valueAndy Grover
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>
2011-07-22target: Enforce 1 page max for control cdb buffer sizesAndy Grover
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>
2011-07-22target: Make all control CDBs scatter-gatherAndy Grover
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>
2011-07-22target: Implement Block Device Characteristics VPD pageRoland Dreier
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>