From e26d99aed42ec6cdc9540d19c77ac5d4dd2c5b00 Mon Sep 17 00:00:00 2001 From: Christoph Hellwig Date: Mon, 14 Nov 2011 12:30:30 -0500 Subject: target: reshuffle headers Create a new headers, drivers/target/target_core_internal.h that is supposed to hold all target_core-internal prototypes. Move all non-exported includes from include/target to it, and merge the smaller prototype-only includes inside drivers/target into it as well. Mark functions that were found to not be called outside their implementation file static. Signed-off-by: Christoph Hellwig Signed-off-by: Nicholas Bellinger --- drivers/target/target_core_transport.c | 67 +++++++++++++++------------------- 1 file changed, 30 insertions(+), 37 deletions(-) (limited to 'drivers/target/target_core_transport.c') diff --git a/drivers/target/target_core_transport.c b/drivers/target/target_core_transport.c index 0257658e2e3..e0ea63dedde 100644 --- a/drivers/target/target_core_transport.c +++ b/drivers/target/target_core_transport.c @@ -52,9 +52,8 @@ #include #include +#include "target_core_internal.h" #include "target_core_alua.h" -#include "target_core_cdb.h" -#include "target_core_hba.h" #include "target_core_pr.h" #include "target_core_ua.h" @@ -212,14 +211,13 @@ u32 scsi_get_new_index(scsi_index_t type) return new_index; } -void transport_init_queue_obj(struct se_queue_obj *qobj) +static void transport_init_queue_obj(struct se_queue_obj *qobj) { atomic_set(&qobj->queue_cnt, 0); INIT_LIST_HEAD(&qobj->qobj_list); init_waitqueue_head(&qobj->thread_wq); spin_lock_init(&qobj->cmd_queue_lock); } -EXPORT_SYMBOL(transport_init_queue_obj); void transport_subsystem_check_init(void) { @@ -896,7 +894,7 @@ void __transport_remove_task_from_execute_queue(struct se_task *task, atomic_dec(&dev->execute_tasks); } -void transport_remove_task_from_execute_queue( +static void transport_remove_task_from_execute_queue( struct se_task *task, struct se_device *dev) { @@ -3345,6 +3343,32 @@ static inline void transport_free_pages(struct se_cmd *cmd) cmd->t_bidi_data_nents = 0; } +/** + * transport_release_cmd - free a command + * @cmd: command to free + * + * This routine unconditionally frees a command, and reference counting + * or list removal must be done in the caller. + */ +static void transport_release_cmd(struct se_cmd *cmd) +{ + BUG_ON(!cmd->se_tfo); + + if (cmd->se_tmr_req) + core_tmr_release_req(cmd->se_tmr_req); + if (cmd->t_task_cdb != cmd->__t_task_cdb) + kfree(cmd->t_task_cdb); + /* + * Check if target_wait_for_sess_cmds() is expecting to + * release se_cmd directly here.. + */ + if (cmd->check_release != 0 && cmd->se_tfo->check_release_cmd) + if (cmd->se_tfo->check_release_cmd(cmd) != 0) + return; + + cmd->se_tfo->release_cmd(cmd); +} + /** * transport_put_cmd - release a reference to a command * @cmd: command to release @@ -3870,33 +3894,6 @@ queue_full: return 0; } -/** - * transport_release_cmd - free a command - * @cmd: command to free - * - * This routine unconditionally frees a command, and reference counting - * or list removal must be done in the caller. - */ -void transport_release_cmd(struct se_cmd *cmd) -{ - BUG_ON(!cmd->se_tfo); - - if (cmd->se_tmr_req) - core_tmr_release_req(cmd->se_tmr_req); - if (cmd->t_task_cdb != cmd->__t_task_cdb) - kfree(cmd->t_task_cdb); - /* - * Check if target_wait_for_sess_cmds() is expecting to - * release se_cmd directly here.. - */ - if (cmd->check_release != 0 && cmd->se_tfo->check_release_cmd) - if (cmd->se_tfo->check_release_cmd(cmd) != 0) - return; - - cmd->se_tfo->release_cmd(cmd); -} -EXPORT_SYMBOL(transport_release_cmd); - void transport_generic_free_cmd(struct se_cmd *cmd, int wait_for_tasks) { if (!(cmd->se_cmd_flags & SCF_SE_LUN_CMD)) { @@ -4545,11 +4542,7 @@ void transport_send_task_abort(struct se_cmd *cmd) cmd->se_tfo->queue_status(cmd); } -/* transport_generic_do_tmr(): - * - * - */ -int transport_generic_do_tmr(struct se_cmd *cmd) +static int transport_generic_do_tmr(struct se_cmd *cmd) { struct se_device *dev = cmd->se_dev; struct se_tmr_req *tmr = cmd->se_tmr_req; -- cgit v1.2.3 From c4795fb20edf2fe2c862c8fe9f8b681edeb79ac1 Mon Sep 17 00:00:00 2001 From: Christoph Hellwig Date: Wed, 16 Nov 2011 09:46:48 -0500 Subject: target: header reshuffle, part2 This reorganized the headers under include/target into: - target_core_base.h stays as is with all target-wide data stuctures and defines - target_core_backend.h contains the whole interface to I/O backends - target_core_fabric.h contains the whole interface to fabric modules Except for those only the various configfs macro headers stay around. Signed-off-by: Christoph Hellwig Signed-off-by: Nicholas Bellinger --- drivers/target/target_core_transport.c | 7 ++----- 1 file changed, 2 insertions(+), 5 deletions(-) (limited to 'drivers/target/target_core_transport.c') diff --git a/drivers/target/target_core_transport.c b/drivers/target/target_core_transport.c index e0ea63dedde..72c13b7a349 100644 --- a/drivers/target/target_core_transport.c +++ b/drivers/target/target_core_transport.c @@ -45,11 +45,8 @@ #include #include -#include -#include -#include -#include -#include +#include +#include #include #include "target_core_internal.h" -- cgit v1.2.3 From ef804a849ffae058a783e9dddd24cc1a555bbdb4 Mon Sep 17 00:00:00 2001 From: Christoph Hellwig Date: Wed, 23 Nov 2011 06:53:58 -0500 Subject: target: fold se_task.task_sense into task_flags Signed-off-by: Christoph Hellwig Signed-off-by: Nicholas Bellinger --- drivers/target/target_core_transport.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) (limited to 'drivers/target/target_core_transport.c') diff --git a/drivers/target/target_core_transport.c b/drivers/target/target_core_transport.c index 72c13b7a349..e13fafa6f52 100644 --- a/drivers/target/target_core_transport.c +++ b/drivers/target/target_core_transport.c @@ -709,7 +709,7 @@ void transport_complete_task(struct se_task *task, int success) if (dev && dev->transport->transport_complete) { if (dev->transport->transport_complete(task) != 0) { cmd->se_cmd_flags |= SCF_TRANSPORT_TASK_SENSE; - task->task_sense = 1; + task->task_flags |= TF_HAS_SENSE; success = 1; } } @@ -2346,7 +2346,7 @@ static int transport_get_sense_data(struct se_cmd *cmd) list_for_each_entry_safe(task, task_tmp, &cmd->t_task_list, t_list) { - if (!task->task_sense) + if (!(task->task_flags & TF_HAS_SENSE)) continue; if (!dev->transport->get_sense_buffer) { -- cgit v1.2.3 From 41e16e981679124c78c30f046d4f0b71d86ff1b2 Mon Sep 17 00:00:00 2001 From: Christoph Hellwig Date: Wed, 23 Nov 2011 06:54:15 -0500 Subject: target: remove the se_task task_error_status field We only reach transport_complete_task once per task, so the test and set on task_error_status is never going to have an effect. Signed-off-by: Christoph Hellwig Signed-off-by: Nicholas Bellinger --- drivers/target/target_core_transport.c | 8 +------- 1 file changed, 1 insertion(+), 7 deletions(-) (limited to 'drivers/target/target_core_transport.c') diff --git a/drivers/target/target_core_transport.c b/drivers/target/target_core_transport.c index e13fafa6f52..ae112ac91c4 100644 --- a/drivers/target/target_core_transport.c +++ b/drivers/target/target_core_transport.c @@ -738,13 +738,7 @@ void transport_complete_task(struct se_task *task, int success) } if (cmd->t_tasks_failed) { - if (!task->task_error_status) { - task->task_error_status = - TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE; - cmd->scsi_sense_reason = - TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE; - } - + cmd->scsi_sense_reason = TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE; INIT_WORK(&cmd->work, target_complete_failure_work); } else { atomic_set(&cmd->t_transport_complete, 1); -- cgit v1.2.3 From 1880807adb21d741f08b747956c90bf4a6f95fbf Mon Sep 17 00:00:00 2001 From: Christoph Hellwig Date: Wed, 23 Nov 2011 06:54:36 -0500 Subject: target: make the se_task task_state_active a normal bool There is no need to make task_state_active an atomic_t given that it is always set under the execute_task_lock so we can make it a simple bool. Also rename it to t_state_active to be closer to the list it guards, and make sure all checks before the list addion/removal actually happen under execute_task_lock. Signed-off-by: Christoph Hellwig Signed-off-by: Nicholas Bellinger --- drivers/target/target_core_transport.c | 41 +++++++++++++++++----------------- 1 file changed, 20 insertions(+), 21 deletions(-) (limited to 'drivers/target/target_core_transport.c') diff --git a/drivers/target/target_core_transport.c b/drivers/target/target_core_transport.c index ae112ac91c4..511836eb295 100644 --- a/drivers/target/target_core_transport.c +++ b/drivers/target/target_core_transport.c @@ -421,18 +421,18 @@ static void transport_all_task_dev_remove_state(struct se_cmd *cmd) if (task->task_flags & TF_ACTIVE) continue; - if (!atomic_read(&task->task_state_active)) - continue; - spin_lock_irqsave(&dev->execute_task_lock, flags); - list_del(&task->t_state_list); - pr_debug("Removed ITT: 0x%08x dev: %p task[%p]\n", - cmd->se_tfo->get_task_tag(cmd), dev, task); - spin_unlock_irqrestore(&dev->execute_task_lock, flags); + if (task->t_state_active) { + pr_debug("Removed ITT: 0x%08x dev: %p task[%p]\n", + cmd->se_tfo->get_task_tag(cmd), dev, task); - atomic_set(&task->task_state_active, 0); - atomic_dec(&cmd->t_task_cdbs_ex_left); + list_del(&task->t_state_list); + atomic_dec(&cmd->t_task_cdbs_ex_left); + task->t_state_active = false; + } + spin_unlock_irqrestore(&dev->execute_task_lock, flags); } + } /* transport_cmd_check_stop(): @@ -813,7 +813,7 @@ static void __transport_add_task_to_execute_queue( head_of_queue = transport_add_task_check_sam_attr(task, task_prev, dev); atomic_inc(&dev->execute_tasks); - if (atomic_read(&task->task_state_active)) + if (task->t_state_active) return; /* * Determine if this task needs to go to HEAD_OF_QUEUE for the @@ -827,7 +827,7 @@ static void __transport_add_task_to_execute_queue( else list_add_tail(&task->t_state_list, &dev->state_task_list); - atomic_set(&task->task_state_active, 1); + task->t_state_active = true; pr_debug("Added ITT: 0x%08x task[%p] to dev: %p\n", task->task_se_cmd->se_tfo->get_task_tag(task->task_se_cmd), @@ -842,17 +842,16 @@ static void transport_add_tasks_to_state_queue(struct se_cmd *cmd) spin_lock_irqsave(&cmd->t_state_lock, flags); list_for_each_entry(task, &cmd->t_task_list, t_list) { - if (atomic_read(&task->task_state_active)) - continue; - spin_lock(&dev->execute_task_lock); - list_add_tail(&task->t_state_list, &dev->state_task_list); - atomic_set(&task->task_state_active, 1); - - pr_debug("Added ITT: 0x%08x task[%p] to dev: %p\n", - task->task_se_cmd->se_tfo->get_task_tag( - task->task_se_cmd), task, dev); - + if (!task->t_state_active) { + list_add_tail(&task->t_state_list, + &dev->state_task_list); + task->t_state_active = true; + + pr_debug("Added ITT: 0x%08x task[%p] to dev: %p\n", + task->task_se_cmd->se_tfo->get_task_tag( + task->task_se_cmd), task, dev); + } spin_unlock(&dev->execute_task_lock); } spin_unlock_irqrestore(&cmd->t_state_lock, flags); -- cgit v1.2.3 From 8359cf43b9dccddeebb0d247146719a14ce6371a Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?J=C3=B6rn=20Engel?= Date: Thu, 24 Nov 2011 02:05:51 +0100 Subject: target: remove useless casts A reader should spend an extra moment whenever noticing a cast, because either something special is going on that deserves extra attention or, as is all too often the case, the code is wrong. These casts, afaics, have all been useless. They cast a foo* to a foo*, cast a void* to the assigned type, cast a foo* to void*, before assigning it to a void* variable, etc. In a few cases I also removed an additional &...[0], which is equally useless. Lastly I added three FIXMEs where, to the best of my judgement, the code appears to have a bug. It would be good if someone could check these. Signed-off-by: Joern Engel Signed-off-by: Nicholas Bellinger --- drivers/target/target_core_transport.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) (limited to 'drivers/target/target_core_transport.c') diff --git a/drivers/target/target_core_transport.c b/drivers/target/target_core_transport.c index 511836eb295..122925686de 100644 --- a/drivers/target/target_core_transport.c +++ b/drivers/target/target_core_transport.c @@ -4161,7 +4161,7 @@ check_cond: static int transport_clear_lun_thread(void *p) { - struct se_lun *lun = (struct se_lun *)p; + struct se_lun *lun = p; __transport_clear_lun_from_sessions(lun); complete(&lun->lun_shutdown_comp); @@ -4580,7 +4580,7 @@ static int transport_processing_thread(void *param) { int ret; struct se_cmd *cmd; - struct se_device *dev = (struct se_device *) param; + struct se_device *dev = param; while (!kthread_should_stop()) { ret = wait_event_interruptible(dev->dev_queue_obj.thread_wq, -- cgit v1.2.3 From 7481deb413be132a22193e8a0bce88b311ecb3c2 Mon Sep 17 00:00:00 2001 From: Nicholas Bellinger Date: Sat, 12 Nov 2011 00:32:17 -0800 Subject: target: Make target_put_sess_cmd use target_release_cmd_kref This patch moves target_put_sess_cmd() to use a se_cmd->cmd_kref callback target_release_cmd_kref when performing driver release of fabric->se_cmd descriptor memory. It sets the default cmd_kref count value to '2' within target_get_sess_cmd() setup, and currently assumes TFO->check_stop_free() usage. It drops se_tfo->check_release_cmd() usage in the main transport_release_cmd codepath. Signed-off-by: Nicholas Bellinger --- drivers/target/target_core_transport.c | 39 +++++++++++++++++++++------------- 1 file changed, 24 insertions(+), 15 deletions(-) (limited to 'drivers/target/target_core_transport.c') diff --git a/drivers/target/target_core_transport.c b/drivers/target/target_core_transport.c index 122925686de..176f956665e 100644 --- a/drivers/target/target_core_transport.c +++ b/drivers/target/target_core_transport.c @@ -3349,13 +3349,13 @@ static void transport_release_cmd(struct se_cmd *cmd) if (cmd->t_task_cdb != cmd->__t_task_cdb) kfree(cmd->t_task_cdb); /* - * Check if target_wait_for_sess_cmds() is expecting to - * release se_cmd directly here.. + * If this cmd has been setup with target_get_sess_cmd(), drop + * the kref and call ->release_cmd() in kref callback. */ - if (cmd->check_release != 0 && cmd->se_tfo->check_release_cmd) - if (cmd->se_tfo->check_release_cmd(cmd) != 0) - return; - + if (cmd->check_release != 0) { + target_put_sess_cmd(cmd->se_sess, cmd); + return; + } cmd->se_tfo->release_cmd(cmd); } @@ -3915,6 +3915,9 @@ void target_get_sess_cmd(struct se_session *se_sess, struct se_cmd *se_cmd) { unsigned long flags; + kref_init(&se_cmd->cmd_kref); + kref_get(&se_cmd->cmd_kref); + spin_lock_irqsave(&se_sess->sess_cmd_lock, flags); list_add_tail(&se_cmd->se_cmd_list, &se_sess->sess_cmd_list); se_cmd->check_release = 1; @@ -3922,30 +3925,36 @@ void target_get_sess_cmd(struct se_session *se_sess, struct se_cmd *se_cmd) } EXPORT_SYMBOL(target_get_sess_cmd); -/* target_put_sess_cmd - Check for active I/O shutdown or list delete - * @se_sess: session to reference - * @se_cmd: command descriptor to drop - */ -int target_put_sess_cmd(struct se_session *se_sess, struct se_cmd *se_cmd) +static void target_release_cmd_kref(struct kref *kref) { + struct se_cmd *se_cmd = container_of(kref, struct se_cmd, cmd_kref); + struct se_session *se_sess = se_cmd->se_sess; unsigned long flags; spin_lock_irqsave(&se_sess->sess_cmd_lock, flags); if (list_empty(&se_cmd->se_cmd_list)) { spin_unlock_irqrestore(&se_sess->sess_cmd_lock, flags); WARN_ON(1); - return 0; + return; } - if (se_sess->sess_tearing_down && se_cmd->cmd_wait_set) { spin_unlock_irqrestore(&se_sess->sess_cmd_lock, flags); complete(&se_cmd->cmd_wait_comp); - return 1; + return; } list_del(&se_cmd->se_cmd_list); spin_unlock_irqrestore(&se_sess->sess_cmd_lock, flags); - return 0; + se_cmd->se_tfo->release_cmd(se_cmd); +} + +/* target_put_sess_cmd - Check for active I/O shutdown via kref_put + * @se_sess: session to reference + * @se_cmd: command descriptor to drop + */ +int target_put_sess_cmd(struct se_session *se_sess, struct se_cmd *se_cmd) +{ + return kref_put(&se_cmd->cmd_kref, target_release_cmd_kref); } EXPORT_SYMBOL(target_put_sess_cmd); -- cgit v1.2.3 From a63607855224702ea17e6016ecf3f7d544e83625 Mon Sep 17 00:00:00 2001 From: Nicholas Bellinger Date: Fri, 18 Nov 2011 20:36:22 -0800 Subject: target: Add target_submit_cmd() for process context fabric submission This patch adds a target_submit_cmd() caller that can be used by fabrics to submit an uninitialized se_cmd descriptor to an struct se_session + unpacked_lun from workqueue process context. This call will invoke the following steps: - transport_init_se_cmd() to setup se_cmd specific pointers - Obtain se_cmd->cmd_kref references with target_get_sess_cmd() - set se_cmd->t_tasks_bidi - transport_lookup_cmd_lun() to setup struct se_cmd->se_lun from the passed unpacked_lun - transport_generic_allocate_tasks() to setup the passed *cdb, and - transport_handle_cdb_direct() handle READ dispatch or WRITE ready-to-transfer callback to fabric v2 changes from hch feedback: *) Add target_sc_flags_table for target_submit_cmd flags *) Rename bidi parameter to flags, add TARGET_SCF_BIDI_OP *) Convert checks to BUG_ON *) Add out_check_cond for transport_send_check_condition_and_sense usage v3 changes: *) Add TARGET_SCF_ACK_KREF for target_submit_cmd into target_get_sess_cmd to determine when the fabric caller is expecting a second kref_put() from fabric packet acknowledgement. Cc: Christoph Hellwig Cc: Roland Dreier Signed-off-by: Nicholas Bellinger --- drivers/target/target_core_transport.c | 86 +++++++++++++++++++++++++++++++++- 1 file changed, 84 insertions(+), 2 deletions(-) (limited to 'drivers/target/target_core_transport.c') diff --git a/drivers/target/target_core_transport.c b/drivers/target/target_core_transport.c index 176f956665e..e4389d40c05 100644 --- a/drivers/target/target_core_transport.c +++ b/drivers/target/target_core_transport.c @@ -1642,6 +1642,80 @@ int transport_handle_cdb_direct( } EXPORT_SYMBOL(transport_handle_cdb_direct); +/** + * target_submit_cmd - lookup unpacked lun and submit uninitialized se_cmd + * + * @se_cmd: command descriptor to submit + * @se_sess: associated se_sess for endpoint + * @cdb: pointer to SCSI CDB + * @sense: pointer to SCSI sense buffer + * @unpacked_lun: unpacked LUN to reference for struct se_lun + * @data_length: fabric expected data transfer length + * @task_addr: SAM task attribute + * @data_dir: DMA data direction + * @flags: flags for command submission from target_sc_flags_tables + * + * This may only be called from process context, and also currently + * assumes internal allocation of fabric payload buffer by target-core. + **/ +int target_submit_cmd(struct se_cmd *se_cmd, struct se_session *se_sess, + unsigned char *cdb, unsigned char *sense, u32 unpacked_lun, + u32 data_length, int task_attr, int data_dir, int flags) +{ + struct se_portal_group *se_tpg; + int rc; + + se_tpg = se_sess->se_tpg; + BUG_ON(!se_tpg); + BUG_ON(se_cmd->se_tfo || se_cmd->se_sess); + BUG_ON(in_interrupt()); + /* + * Initialize se_cmd for target operation. From this point + * exceptions are handled by sending exception status via + * target_core_fabric_ops->queue_status() callback + */ + transport_init_se_cmd(se_cmd, se_tpg->se_tpg_tfo, se_sess, + data_length, data_dir, task_attr, sense); + /* + * Obtain struct se_cmd->cmd_kref reference and add new cmd to + * se_sess->sess_cmd_list. A second kref_get here is necessary + * for fabrics using TARGET_SCF_ACK_KREF that expect a second + * kref_put() to happen during fabric packet acknowledgement. + */ + target_get_sess_cmd(se_sess, se_cmd, (flags & TARGET_SCF_ACK_KREF)); + /* + * Signal bidirectional data payloads to target-core + */ + if (flags & TARGET_SCF_BIDI_OP) + se_cmd->se_cmd_flags |= SCF_BIDI; + /* + * Locate se_lun pointer and attach it to struct se_cmd + */ + if (transport_lookup_cmd_lun(se_cmd, unpacked_lun) < 0) + goto out_check_cond; + /* + * Sanitize CDBs via transport_generic_cmd_sequencer() and + * allocate the necessary tasks to complete the received CDB+data + */ + rc = transport_generic_allocate_tasks(se_cmd, cdb); + if (rc != 0) + goto out_check_cond; + /* + * Dispatch se_cmd descriptor to se_lun->lun_se_dev backend + * for immediate execution of READs, otherwise wait for + * transport_generic_handle_data() to be called for WRITEs + * when fabric has filled the incoming buffer. + */ + transport_handle_cdb_direct(se_cmd); + return 0; + +out_check_cond: + transport_send_check_condition_and_sense(se_cmd, + se_cmd->scsi_sense_reason, 0); + return 0; +} +EXPORT_SYMBOL(target_submit_cmd); + /* * Used by fabric module frontends defining a TFO->new_cmd_map() caller * to queue up a newly setup se_cmd w/ TRANSPORT_NEW_CMD_MAP in order to @@ -3910,13 +3984,21 @@ EXPORT_SYMBOL(transport_generic_free_cmd); /* target_get_sess_cmd - Add command to active ->sess_cmd_list * @se_sess: session to reference * @se_cmd: command descriptor to add + * @ack_kref: Signal that fabric will perform an ack target_put_sess_cmd() */ -void target_get_sess_cmd(struct se_session *se_sess, struct se_cmd *se_cmd) +void target_get_sess_cmd(struct se_session *se_sess, struct se_cmd *se_cmd, + bool ack_kref) { unsigned long flags; kref_init(&se_cmd->cmd_kref); - kref_get(&se_cmd->cmd_kref); + /* + * Add a second kref if the fabric caller is expecting to handle + * fabric acknowledgement that requires two target_put_sess_cmd() + * invocations before se_cmd descriptor release. + */ + if (ack_kref == true) + kref_get(&se_cmd->cmd_kref); spin_lock_irqsave(&se_sess->sess_cmd_lock, flags); list_add_tail(&se_cmd->se_cmd_list, &se_sess->sess_cmd_list); -- cgit v1.2.3 From 40be67f4c588fe2f3e2dbd60ae1f470abc5b6ad8 Mon Sep 17 00:00:00 2001 From: Nicholas Bellinger Date: Wed, 30 Nov 2011 00:41:20 -0800 Subject: target: Fix possible NULL pointer with __transport_execute_tasks This patch makes __transport_execute_tasks() use a local *se_dev reference to prevent direct se_cmd->se_dev access after transport_cmd_check_stop() -> transport_add_tasks_from_cmd() has been called, as in the current implementation we can expect __transport_execute_tasks() may be called from another context that may have already completed the I/O. Cc: Christoph Hellwig Signed-off-by: Nicholas Bellinger --- drivers/target/target_core_transport.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) (limited to 'drivers/target/target_core_transport.c') diff --git a/drivers/target/target_core_transport.c b/drivers/target/target_core_transport.c index e4389d40c05..1cc7e920ab0 100644 --- a/drivers/target/target_core_transport.c +++ b/drivers/target/target_core_transport.c @@ -2076,6 +2076,7 @@ static inline int transport_execute_task_attr(struct se_cmd *cmd) static int transport_execute_tasks(struct se_cmd *cmd) { int add_tasks; + struct se_device *se_dev = cmd->se_dev; if (se_dev_check_online(cmd->se_dev) != 0) { cmd->scsi_sense_reason = TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE; @@ -2108,7 +2109,7 @@ static int transport_execute_tasks(struct se_cmd *cmd) * storage object. */ execute_tasks: - __transport_execute_tasks(cmd->se_dev); + __transport_execute_tasks(se_dev); return 0; } -- cgit v1.2.3 From 65586d51e0986be574118286c3d0007e903a2add Mon Sep 17 00:00:00 2001 From: Nicholas Bellinger Date: Wed, 30 Nov 2011 01:25:21 -0800 Subject: target: Drop se_device TCQ queue_depth usage from I/O path Historically, pSCSI devices have been the ones that required target-core to enforce a per se_device->depth_left. This patch changes target-core to no longer (by default) enforce a per se_device->depth_left or sleep in transport_tcq_window_closed() when we out of queue slots for all backend export cases. Cc: Christoph Hellwig Cc: Roland Dreier Cc: Joern Engel Signed-off-by: Nicholas Bellinger --- drivers/target/target_core_transport.c | 39 ++-------------------------------- 1 file changed, 2 insertions(+), 37 deletions(-) (limited to 'drivers/target/target_core_transport.c') diff --git a/drivers/target/target_core_transport.c b/drivers/target/target_core_transport.c index 1cc7e920ab0..7c2def7e259 100644 --- a/drivers/target/target_core_transport.c +++ b/drivers/target/target_core_transport.c @@ -691,12 +691,6 @@ void transport_complete_task(struct se_task *task, int success) struct se_cmd *cmd = task->task_se_cmd; struct se_device *dev = cmd->se_dev; unsigned long flags; -#if 0 - pr_debug("task: %p CDB: 0x%02x obj_ptr: %p\n", task, - cmd->t_task_cdb[0], dev); -#endif - if (dev) - atomic_inc(&dev->depth_left); spin_lock_irqsave(&cmd->t_state_lock, flags); task->task_flags &= ~TF_ACTIVE; @@ -971,9 +965,8 @@ void transport_dump_dev_state( break; } - *bl += sprintf(b + *bl, " Execute/Left/Max Queue Depth: %d/%d/%d", - atomic_read(&dev->execute_tasks), atomic_read(&dev->depth_left), - dev->queue_depth); + *bl += sprintf(b + *bl, " Execute/Max Queue Depth: %d/%d", + atomic_read(&dev->execute_tasks), dev->queue_depth); *bl += sprintf(b + *bl, " SectorSize: %u MaxSectors: %u\n", dev->se_sub_dev->se_dev_attrib.block_size, dev->se_sub_dev->se_dev_attrib.max_sectors); *bl += sprintf(b + *bl, " "); @@ -1328,9 +1321,6 @@ struct se_device *transport_add_device_to_core_hba( spin_lock_init(&dev->se_port_lock); spin_lock_init(&dev->se_tmr_lock); spin_lock_init(&dev->qf_cmd_lock); - - dev->queue_depth = dev_limits->queue_depth; - atomic_set(&dev->depth_left, dev->queue_depth); atomic_set(&dev->dev_ordered_id, 0); se_dev_set_default_attribs(dev, dev_limits); @@ -1982,18 +1972,6 @@ static void transport_set_supported_SAM_opcode(struct se_cmd *se_cmd) spin_unlock_irqrestore(&se_cmd->t_state_lock, flags); } -static inline int transport_tcq_window_closed(struct se_device *dev) -{ - if (dev->dev_tcq_window_closed++ < - PYX_TRANSPORT_WINDOW_CLOSED_THRESHOLD) { - msleep(PYX_TRANSPORT_WINDOW_CLOSED_WAIT_SHORT); - } else - msleep(PYX_TRANSPORT_WINDOW_CLOSED_WAIT_LONG); - - wake_up_interruptible(&dev->dev_queue_obj.thread_wq); - return 0; -} - /* * Called from Fabric Module context from transport_execute_tasks() * @@ -2126,16 +2104,7 @@ static int __transport_execute_tasks(struct se_device *dev) struct se_task *task = NULL; unsigned long flags; - /* - * Check if there is enough room in the device and HBA queue to send - * struct se_tasks to the selected transport. - */ check_depth: - if (!atomic_read(&dev->depth_left)) - return transport_tcq_window_closed(dev); - - dev->dev_tcq_window_closed = 0; - spin_lock_irq(&dev->execute_task_lock); if (list_empty(&dev->execute_task_list)) { spin_unlock_irq(&dev->execute_task_lock); @@ -2146,10 +2115,7 @@ check_depth: __transport_remove_task_from_execute_queue(task, dev); spin_unlock_irq(&dev->execute_task_lock); - atomic_dec(&dev->depth_left); - cmd = task->task_se_cmd; - spin_lock_irqsave(&cmd->t_state_lock, flags); task->task_flags |= (TF_ACTIVE | TF_SENT); atomic_inc(&cmd->t_task_cdbs_sent); @@ -2170,7 +2136,6 @@ check_depth: spin_unlock_irqrestore(&cmd->t_state_lock, flags); atomic_set(&cmd->t_transport_sent, 0); transport_stop_tasks_for_cmd(cmd); - atomic_inc(&dev->depth_left); transport_generic_request_failure(cmd); } -- cgit v1.2.3 From 4d2300ccffd22d1d0213b6a8e4d685eb6ca069c0 Mon Sep 17 00:00:00 2001 From: Nicholas Bellinger Date: Wed, 30 Nov 2011 18:18:33 -0800 Subject: target: Remove extra se_device->execute_task_lock access in fast path This patch makes __transport_execute_tasks() perform the addition of tasks to dev->execute_task_list via __transport_add_tasks_from_cmd() while holding dev->execute_task_lock during normal I/O fast path submission. It effectively removes the unnecessary re-acquire of dev->execute_task_lock during transport_execute_tasks() -> transport_add_tasks_from_cmd() ahead of calling __transport_execute_tasks() to queue tasks for the passed *se_cmd descriptor. (v2: Re-add goto check_depth usage for multi-task submission for now..) Cc: Christoph Hellwig Cc: Roland Dreier Cc: Joern Engel Signed-off-by: Nicholas Bellinger --- drivers/target/target_core_transport.c | 40 ++++++++++++++++++++-------------- 1 file changed, 24 insertions(+), 16 deletions(-) (limited to 'drivers/target/target_core_transport.c') diff --git a/drivers/target/target_core_transport.c b/drivers/target/target_core_transport.c index 7c2def7e259..46e25118ab2 100644 --- a/drivers/target/target_core_transport.c +++ b/drivers/target/target_core_transport.c @@ -68,7 +68,7 @@ struct kmem_cache *t10_alua_tg_pt_gp_mem_cache; static int transport_generic_write_pending(struct se_cmd *); static int transport_processing_thread(void *param); -static int __transport_execute_tasks(struct se_device *dev); +static int __transport_execute_tasks(struct se_device *dev, struct se_cmd *); static void transport_complete_task_attr(struct se_cmd *cmd); static void transport_handle_queue_full(struct se_cmd *cmd, struct se_device *dev); @@ -851,13 +851,11 @@ static void transport_add_tasks_to_state_queue(struct se_cmd *cmd) spin_unlock_irqrestore(&cmd->t_state_lock, flags); } -static void transport_add_tasks_from_cmd(struct se_cmd *cmd) +static void __transport_add_tasks_from_cmd(struct se_cmd *cmd) { struct se_device *dev = cmd->se_dev; struct se_task *task, *task_prev = NULL; - unsigned long flags; - spin_lock_irqsave(&dev->execute_task_lock, flags); list_for_each_entry(task, &cmd->t_task_list, t_list) { if (!list_empty(&task->t_execute_list)) continue; @@ -868,6 +866,15 @@ static void transport_add_tasks_from_cmd(struct se_cmd *cmd) __transport_add_task_to_execute_queue(task, task_prev, dev); task_prev = task; } +} + +static void transport_add_tasks_from_cmd(struct se_cmd *cmd) +{ + unsigned long flags; + struct se_device *dev = cmd->se_dev; + + spin_lock_irqsave(&dev->execute_task_lock, flags); + __transport_add_tasks_from_cmd(cmd); spin_unlock_irqrestore(&dev->execute_task_lock, flags); } @@ -2075,19 +2082,16 @@ static int transport_execute_tasks(struct se_cmd *cmd) if (!add_tasks) goto execute_tasks; /* - * This calls transport_add_tasks_from_cmd() to handle - * HEAD_OF_QUEUE ordering for SAM Task Attribute emulation - * (if enabled) in __transport_add_task_to_execute_queue() and - * transport_add_task_check_sam_attr(). + * __transport_execute_tasks() -> __transport_add_tasks_from_cmd() + * adds associated se_tasks while holding dev->execute_task_lock + * before I/O dispath to avoid a double spinlock access. */ - transport_add_tasks_from_cmd(cmd); + __transport_execute_tasks(se_dev, cmd); + return 0; } - /* - * Kick the execution queue for the cmd associated struct se_device - * storage object. - */ + execute_tasks: - __transport_execute_tasks(se_dev); + __transport_execute_tasks(se_dev, NULL); return 0; } @@ -2097,7 +2101,7 @@ execute_tasks: * * Called from transport_processing_thread() */ -static int __transport_execute_tasks(struct se_device *dev) +static int __transport_execute_tasks(struct se_device *dev, struct se_cmd *new_cmd) { int error; struct se_cmd *cmd = NULL; @@ -2106,6 +2110,9 @@ static int __transport_execute_tasks(struct se_device *dev) check_depth: spin_lock_irq(&dev->execute_task_lock); + if (new_cmd != NULL) + __transport_add_tasks_from_cmd(new_cmd); + if (list_empty(&dev->execute_task_list)) { spin_unlock_irq(&dev->execute_task_lock); return 0; @@ -2139,6 +2146,7 @@ check_depth: transport_generic_request_failure(cmd); } + new_cmd = NULL; goto check_depth; return 0; @@ -4647,7 +4655,7 @@ static int transport_processing_thread(void *param) goto out; get_cmd: - __transport_execute_tasks(dev); + __transport_execute_tasks(dev, NULL); cmd = transport_get_cmd_from_queue(&dev->dev_queue_obj); if (!cmd) -- cgit v1.2.3 From beb55a0cc15a43be43a646b588fcf83822f0c44f Mon Sep 17 00:00:00 2001 From: Nicholas Bellinger Date: Wed, 30 Nov 2011 18:21:24 -0800 Subject: target: Remove __transport_execute_tasks() for each processing context This patch removes the original usage of __transport_execute_tasks() ahead of every transport_get_cmd_from_queue() call in transport_processing_thread(). This helps reduce se_device->execute_task_lock contention between qla2xxx wq with target_submit_cmd() for READs and transport_processing_thread() context servicing WRITEs with full payloads for I/O submission. It also adds a __transport_execute_tasks() to kick the task queue again without a *se_cmd descriptor with existing queue full logic, but this may end up not being necessary. Cc: Christoph Hellwig Cc: Roland Dreier Cc: Joern Engel Signed-off-by: Nicholas Bellinger --- drivers/target/target_core_transport.c | 2 -- 1 file changed, 2 deletions(-) (limited to 'drivers/target/target_core_transport.c') diff --git a/drivers/target/target_core_transport.c b/drivers/target/target_core_transport.c index 46e25118ab2..373e01f523d 100644 --- a/drivers/target/target_core_transport.c +++ b/drivers/target/target_core_transport.c @@ -4655,8 +4655,6 @@ static int transport_processing_thread(void *param) goto out; get_cmd: - __transport_execute_tasks(dev, NULL); - cmd = transport_get_cmd_from_queue(&dev->dev_queue_obj); if (!cmd) continue; -- cgit v1.2.3 From 6d5b59756033c2a029bde7262bb5f8d45f4ca952 Mon Sep 17 00:00:00 2001 From: Nicholas Bellinger Date: Wed, 30 Nov 2011 18:24:03 -0800 Subject: target: Remove legacy device status check from transport_execute_tasks This patch removes a legacy se_dev_check_online() check from within transport_execute_tasks() that should no longer be necessary as transport_lookup_cmd_lun() is already making this call. Using transport_cmd_check_stop() from transport_execute_tasks() should already be checking per se_cmd context for each descriptor upon active I/O shutdown, so no need to acquire dev->dev_status_lock again while executing se_task submission. Cc: Christoph Hellwig Cc: Roland Dreier Cc: Joern Engel Signed-off-by: Nicholas Bellinger --- drivers/target/target_core_transport.c | 7 ------- 1 file changed, 7 deletions(-) (limited to 'drivers/target/target_core_transport.c') diff --git a/drivers/target/target_core_transport.c b/drivers/target/target_core_transport.c index 373e01f523d..b5fdacce067 100644 --- a/drivers/target/target_core_transport.c +++ b/drivers/target/target_core_transport.c @@ -2062,13 +2062,6 @@ static int transport_execute_tasks(struct se_cmd *cmd) { int add_tasks; struct se_device *se_dev = cmd->se_dev; - - if (se_dev_check_online(cmd->se_dev) != 0) { - cmd->scsi_sense_reason = TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE; - transport_generic_request_failure(cmd); - return 0; - } - /* * Call transport_cmd_check_stop() to see if a fabric exception * has occurred that prevents execution. -- cgit v1.2.3 From 895f3022523361e9b383cf48f51feb1f7d5e7e53 Mon Sep 17 00:00:00 2001 From: Roland Dreier Date: Tue, 13 Dec 2011 14:55:33 -0800 Subject: target: Set additional sense length field in sense data The target code was not setting the additional sense length field in the sense data it returned, which meant that at least the Linux stack ignored the ASC/ASCQ fields. For example, without this patch, on a tcm_loop device: # sg_raw -v /dev/sda 2 0 0 0 0 0 gives cdb to send: 02 00 00 00 00 00 SCSI Status: Check Condition Sense Information: Fixed format, current; Sense key: Illegal Request Raw sense data (in hex): 70 00 05 00 00 00 00 00 while after the patch we correctly get the following (which matches what a regular disk returns): cdb to send: 02 00 00 00 00 00 SCSI Status: Check Condition Sense Information: Fixed format, current; Sense key: Illegal Request Additional sense: Invalid command operation code Raw sense data (in hex): 70 00 05 00 00 00 00 0a 00 00 00 00 20 00 00 00 00 00 Signed-off-by: Roland Dreier Cc: stable@kernel.org Signed-off-by: Nicholas Bellinger --- drivers/target/target_core_transport.c | 14 ++++++++++++++ 1 file changed, 14 insertions(+) (limited to 'drivers/target/target_core_transport.c') diff --git a/drivers/target/target_core_transport.c b/drivers/target/target_core_transport.c index b5fdacce067..d3ddd136194 100644 --- a/drivers/target/target_core_transport.c +++ b/drivers/target/target_core_transport.c @@ -4398,6 +4398,7 @@ int transport_send_check_condition_and_sense( case TCM_NON_EXISTENT_LUN: /* CURRENT ERROR */ buffer[offset] = 0x70; + buffer[offset+SPC_ADD_SENSE_LEN_OFFSET] = 10; /* ILLEGAL REQUEST */ buffer[offset+SPC_SENSE_KEY_OFFSET] = ILLEGAL_REQUEST; /* LOGICAL UNIT NOT SUPPORTED */ @@ -4407,6 +4408,7 @@ int transport_send_check_condition_and_sense( case TCM_SECTOR_COUNT_TOO_MANY: /* CURRENT ERROR */ buffer[offset] = 0x70; + buffer[offset+SPC_ADD_SENSE_LEN_OFFSET] = 10; /* ILLEGAL REQUEST */ buffer[offset+SPC_SENSE_KEY_OFFSET] = ILLEGAL_REQUEST; /* INVALID COMMAND OPERATION CODE */ @@ -4415,6 +4417,7 @@ int transport_send_check_condition_and_sense( case TCM_UNKNOWN_MODE_PAGE: /* CURRENT ERROR */ buffer[offset] = 0x70; + buffer[offset+SPC_ADD_SENSE_LEN_OFFSET] = 10; /* ILLEGAL REQUEST */ buffer[offset+SPC_SENSE_KEY_OFFSET] = ILLEGAL_REQUEST; /* INVALID FIELD IN CDB */ @@ -4423,6 +4426,7 @@ int transport_send_check_condition_and_sense( case TCM_CHECK_CONDITION_ABORT_CMD: /* CURRENT ERROR */ buffer[offset] = 0x70; + buffer[offset+SPC_ADD_SENSE_LEN_OFFSET] = 10; /* ABORTED COMMAND */ buffer[offset+SPC_SENSE_KEY_OFFSET] = ABORTED_COMMAND; /* BUS DEVICE RESET FUNCTION OCCURRED */ @@ -4432,6 +4436,7 @@ int transport_send_check_condition_and_sense( case TCM_INCORRECT_AMOUNT_OF_DATA: /* CURRENT ERROR */ buffer[offset] = 0x70; + buffer[offset+SPC_ADD_SENSE_LEN_OFFSET] = 10; /* ABORTED COMMAND */ buffer[offset+SPC_SENSE_KEY_OFFSET] = ABORTED_COMMAND; /* WRITE ERROR */ @@ -4442,6 +4447,7 @@ int transport_send_check_condition_and_sense( case TCM_INVALID_CDB_FIELD: /* CURRENT ERROR */ buffer[offset] = 0x70; + buffer[offset+SPC_ADD_SENSE_LEN_OFFSET] = 10; /* ABORTED COMMAND */ buffer[offset+SPC_SENSE_KEY_OFFSET] = ABORTED_COMMAND; /* INVALID FIELD IN CDB */ @@ -4450,6 +4456,7 @@ int transport_send_check_condition_and_sense( case TCM_INVALID_PARAMETER_LIST: /* CURRENT ERROR */ buffer[offset] = 0x70; + buffer[offset+SPC_ADD_SENSE_LEN_OFFSET] = 10; /* ABORTED COMMAND */ buffer[offset+SPC_SENSE_KEY_OFFSET] = ABORTED_COMMAND; /* INVALID FIELD IN PARAMETER LIST */ @@ -4458,6 +4465,7 @@ int transport_send_check_condition_and_sense( case TCM_UNEXPECTED_UNSOLICITED_DATA: /* CURRENT ERROR */ buffer[offset] = 0x70; + buffer[offset+SPC_ADD_SENSE_LEN_OFFSET] = 10; /* ABORTED COMMAND */ buffer[offset+SPC_SENSE_KEY_OFFSET] = ABORTED_COMMAND; /* WRITE ERROR */ @@ -4468,6 +4476,7 @@ int transport_send_check_condition_and_sense( case TCM_SERVICE_CRC_ERROR: /* CURRENT ERROR */ buffer[offset] = 0x70; + buffer[offset+SPC_ADD_SENSE_LEN_OFFSET] = 10; /* ABORTED COMMAND */ buffer[offset+SPC_SENSE_KEY_OFFSET] = ABORTED_COMMAND; /* PROTOCOL SERVICE CRC ERROR */ @@ -4478,6 +4487,7 @@ int transport_send_check_condition_and_sense( case TCM_SNACK_REJECTED: /* CURRENT ERROR */ buffer[offset] = 0x70; + buffer[offset+SPC_ADD_SENSE_LEN_OFFSET] = 10; /* ABORTED COMMAND */ buffer[offset+SPC_SENSE_KEY_OFFSET] = ABORTED_COMMAND; /* READ ERROR */ @@ -4488,6 +4498,7 @@ int transport_send_check_condition_and_sense( case TCM_WRITE_PROTECTED: /* CURRENT ERROR */ buffer[offset] = 0x70; + buffer[offset+SPC_ADD_SENSE_LEN_OFFSET] = 10; /* DATA PROTECT */ buffer[offset+SPC_SENSE_KEY_OFFSET] = DATA_PROTECT; /* WRITE PROTECTED */ @@ -4496,6 +4507,7 @@ int transport_send_check_condition_and_sense( case TCM_CHECK_CONDITION_UNIT_ATTENTION: /* CURRENT ERROR */ buffer[offset] = 0x70; + buffer[offset+SPC_ADD_SENSE_LEN_OFFSET] = 10; /* UNIT ATTENTION */ buffer[offset+SPC_SENSE_KEY_OFFSET] = UNIT_ATTENTION; core_scsi3_ua_for_check_condition(cmd, &asc, &ascq); @@ -4505,6 +4517,7 @@ int transport_send_check_condition_and_sense( case TCM_CHECK_CONDITION_NOT_READY: /* CURRENT ERROR */ buffer[offset] = 0x70; + buffer[offset+SPC_ADD_SENSE_LEN_OFFSET] = 10; /* Not Ready */ buffer[offset+SPC_SENSE_KEY_OFFSET] = NOT_READY; transport_get_sense_codes(cmd, &asc, &ascq); @@ -4515,6 +4528,7 @@ int transport_send_check_condition_and_sense( default: /* CURRENT ERROR */ buffer[offset] = 0x70; + buffer[offset+SPC_ADD_SENSE_LEN_OFFSET] = 10; /* ILLEGAL REQUEST */ buffer[offset+SPC_SENSE_KEY_OFFSET] = ILLEGAL_REQUEST; /* LOGICAL UNIT COMMUNICATION FAILURE */ -- cgit v1.2.3