diff options
author | Alex Shi <alex.shi@linaro.org> | 2016-03-18 12:01:50 +0800 |
---|---|---|
committer | Alex Shi <alex.shi@linaro.org> | 2016-03-18 12:01:50 +0800 |
commit | 864b6e70253ae07b58bb126d29a35be22f50f453 (patch) | |
tree | 21f2021685284c01035f1cf03c1ff0b3c66da008 /drivers/target/target_core_transport.c | |
parent | 405b4c1452cb59ce07632a60d3e3152ab9243ae6 (diff) | |
parent | 421a8ddd1fc901897eee73965b442af4b4dd7095 (diff) |
Merge branch 'linux-linaro-lsk-v3.18' into linux-linaro-lsk-v3.18-androidlsk-v3.18-16.03-android
Diffstat (limited to 'drivers/target/target_core_transport.c')
-rw-r--r-- | drivers/target/target_core_transport.c | 267 |
1 files changed, 183 insertions, 84 deletions
diff --git a/drivers/target/target_core_transport.c b/drivers/target/target_core_transport.c index adf96b78e9f0..b6051c82f386 100644 --- a/drivers/target/target_core_transport.c +++ b/drivers/target/target_core_transport.c @@ -515,9 +515,6 @@ void transport_deregister_session(struct se_session *se_sess) } EXPORT_SYMBOL(transport_deregister_session); -/* - * Called with cmd->t_state_lock held. - */ static void target_remove_from_state_list(struct se_cmd *cmd) { struct se_device *dev = cmd->se_dev; @@ -542,10 +539,6 @@ static int transport_cmd_check_stop(struct se_cmd *cmd, bool remove_from_lists, { unsigned long flags; - spin_lock_irqsave(&cmd->t_state_lock, flags); - if (write_pending) - cmd->t_state = TRANSPORT_WRITE_PENDING; - if (remove_from_lists) { target_remove_from_state_list(cmd); @@ -555,6 +548,10 @@ static int transport_cmd_check_stop(struct se_cmd *cmd, bool remove_from_lists, cmd->se_lun = NULL; } + spin_lock_irqsave(&cmd->t_state_lock, flags); + if (write_pending) + cmd->t_state = TRANSPORT_WRITE_PENDING; + /* * Determine if frontend context caller is requesting the stopping of * this command for frontend exceptions. @@ -609,6 +606,8 @@ static void transport_lun_remove_cmd(struct se_cmd *cmd) void transport_cmd_finish_abort(struct se_cmd *cmd, int remove) { + bool ack_kref = (cmd->se_cmd_flags & SCF_ACK_KREF); + if (cmd->se_cmd_flags & SCF_SE_LUN_CMD) transport_lun_remove_cmd(cmd); /* @@ -620,7 +619,7 @@ void transport_cmd_finish_abort(struct se_cmd *cmd, int remove) if (transport_cmd_check_stop_to_fabric(cmd)) return; - if (remove) + if (remove && ack_kref) transport_put_cmd(cmd); } @@ -688,7 +687,7 @@ void target_complete_cmd(struct se_cmd *cmd, u8 scsi_status) * Check for case where an explicit ABORT_TASK has been received * and transport_wait_for_tasks() will be waiting for completion.. */ - if (cmd->transport_state & CMD_T_ABORTED && + if (cmd->transport_state & CMD_T_ABORTED || cmd->transport_state & CMD_T_STOP) { spin_unlock_irqrestore(&cmd->t_state_lock, flags); complete_all(&cmd->t_transport_stop_comp); @@ -1596,7 +1595,7 @@ bool target_stop_cmd(struct se_cmd *cmd, unsigned long *flags) void transport_generic_request_failure(struct se_cmd *cmd, sense_reason_t sense_reason) { - int ret = 0; + int ret = 0, post_ret = 0; pr_debug("-----[ Storage Engine Exception for cmd: %p ITT: 0x%08x" " CDB: 0x%02x\n", cmd, cmd->se_tfo->get_task_tag(cmd), @@ -1619,7 +1618,7 @@ void transport_generic_request_failure(struct se_cmd *cmd, */ if ((cmd->se_cmd_flags & SCF_COMPARE_AND_WRITE) && cmd->transport_complete_callback) - cmd->transport_complete_callback(cmd, false); + cmd->transport_complete_callback(cmd, false, &post_ret); switch (sense_reason) { case TCM_NON_EXISTENT_LUN: @@ -1759,19 +1758,21 @@ static bool target_handle_task_attr(struct se_cmd *cmd) return true; } +static int __transport_check_aborted_status(struct se_cmd *, int); + void target_execute_cmd(struct se_cmd *cmd) { /* - * If the received CDB has aleady been aborted stop processing it here. - */ - if (transport_check_aborted_status(cmd, 1)) - return; - - /* * Determine if frontend context caller is requesting the stopping of * this command for frontend exceptions. + * + * If the received CDB has aleady been aborted stop processing it here. */ spin_lock_irq(&cmd->t_state_lock); + if (__transport_check_aborted_status(cmd, 1)) { + spin_unlock_irq(&cmd->t_state_lock); + return; + } if (cmd->transport_state & CMD_T_STOP) { pr_debug("%s:%d CMD_T_STOP for ITT: 0x%08x\n", __func__, __LINE__, @@ -1974,11 +1975,13 @@ static void target_complete_ok_work(struct work_struct *work) */ if (cmd->transport_complete_callback) { sense_reason_t rc; + bool caw = (cmd->se_cmd_flags & SCF_COMPARE_AND_WRITE); + bool zero_dl = !(cmd->data_length); + int post_ret = 0; - rc = cmd->transport_complete_callback(cmd, true); - if (!rc && !(cmd->se_cmd_flags & SCF_COMPARE_AND_WRITE_POST)) { - if ((cmd->se_cmd_flags & SCF_COMPARE_AND_WRITE) && - !cmd->data_length) + rc = cmd->transport_complete_callback(cmd, true, &post_ret); + if (!rc && !post_ret) { + if (caw && zero_dl) goto queue_rsp; return; @@ -2128,20 +2131,14 @@ static inline void transport_free_pages(struct se_cmd *cmd) } /** - * transport_release_cmd - free a command - * @cmd: command to free + * transport_put_cmd - release a reference to a command + * @cmd: command to release * - * This routine unconditionally frees a command, and reference counting - * or list removal must be done in the caller. + * This routine releases our reference to the command and frees it if possible. */ -static int transport_release_cmd(struct se_cmd *cmd) +static int transport_put_cmd(struct se_cmd *cmd) { BUG_ON(!cmd->se_tfo); - - if (cmd->se_cmd_flags & SCF_SCSI_TMR_CDB) - core_tmr_release_req(cmd->se_tmr_req); - if (cmd->t_task_cdb != cmd->__t_task_cdb) - kfree(cmd->t_task_cdb); /* * If this cmd has been setup with target_get_sess_cmd(), drop * the kref and call ->release_cmd() in kref callback. @@ -2149,18 +2146,6 @@ static int transport_release_cmd(struct se_cmd *cmd) return target_put_sess_cmd(cmd); } -/** - * transport_put_cmd - release a reference to a command - * @cmd: command to release - * - * This routine releases our reference to the command and frees it if possible. - */ -static int transport_put_cmd(struct se_cmd *cmd) -{ - transport_free_pages(cmd); - return transport_release_cmd(cmd); -} - void *transport_kmap_data_sg(struct se_cmd *cmd) { struct scatterlist *sg = cmd->t_data_sg; @@ -2356,34 +2341,59 @@ static void transport_write_pending_qf(struct se_cmd *cmd) } } -int transport_generic_free_cmd(struct se_cmd *cmd, int wait_for_tasks) +static bool +__transport_wait_for_tasks(struct se_cmd *, bool, bool *, bool *, + unsigned long *flags); + +static void target_wait_free_cmd(struct se_cmd *cmd, bool *aborted, bool *tas) { unsigned long flags; + + spin_lock_irqsave(&cmd->t_state_lock, flags); + __transport_wait_for_tasks(cmd, true, aborted, tas, &flags); + spin_unlock_irqrestore(&cmd->t_state_lock, flags); +} + +int transport_generic_free_cmd(struct se_cmd *cmd, int wait_for_tasks) +{ int ret = 0; + bool aborted = false, tas = false; if (!(cmd->se_cmd_flags & SCF_SE_LUN_CMD)) { if (wait_for_tasks && (cmd->se_cmd_flags & SCF_SCSI_TMR_CDB)) - transport_wait_for_tasks(cmd); + target_wait_free_cmd(cmd, &aborted, &tas); - ret = transport_release_cmd(cmd); + if (!aborted || tas) + ret = transport_put_cmd(cmd); } else { if (wait_for_tasks) - transport_wait_for_tasks(cmd); + target_wait_free_cmd(cmd, &aborted, &tas); /* * Handle WRITE failure case where transport_generic_new_cmd() * has already added se_cmd to state_list, but fabric has * failed command before I/O submission. */ - if (cmd->state_active) { - spin_lock_irqsave(&cmd->t_state_lock, flags); + if (cmd->state_active) target_remove_from_state_list(cmd); - spin_unlock_irqrestore(&cmd->t_state_lock, flags); - } if (cmd->se_lun) transport_lun_remove_cmd(cmd); - ret = transport_put_cmd(cmd); + if (!aborted || tas) + ret = transport_put_cmd(cmd); + } + /* + * If the task has been internally aborted due to TMR ABORT_TASK + * or LUN_RESET, target_core_tmr.c is responsible for performing + * the remaining calls to target_put_sess_cmd(), and not the + * callers of this function. + */ + if (aborted) { + pr_debug("Detected CMD_T_ABORTED for ITT: %u\n", + cmd->se_tfo->get_task_tag(cmd)); + wait_for_completion(&cmd->cmd_wait_comp); + cmd->se_tfo->release_cmd(cmd); + ret = 1; } return ret; } @@ -2425,24 +2435,44 @@ out: } EXPORT_SYMBOL(target_get_sess_cmd); +static void target_free_cmd_mem(struct se_cmd *cmd) +{ + transport_free_pages(cmd); + + if (cmd->se_cmd_flags & SCF_SCSI_TMR_CDB) + core_tmr_release_req(cmd->se_tmr_req); + if (cmd->t_task_cdb != cmd->__t_task_cdb) + kfree(cmd->t_task_cdb); +} + 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; + bool fabric_stop; if (list_empty(&se_cmd->se_cmd_list)) { spin_unlock(&se_sess->sess_cmd_lock); + target_free_cmd_mem(se_cmd); se_cmd->se_tfo->release_cmd(se_cmd); return; } - if (se_sess->sess_tearing_down && se_cmd->cmd_wait_set) { + + spin_lock(&se_cmd->t_state_lock); + fabric_stop = (se_cmd->transport_state & CMD_T_FABRIC_STOP); + spin_unlock(&se_cmd->t_state_lock); + + if (se_cmd->cmd_wait_set || fabric_stop) { + list_del_init(&se_cmd->se_cmd_list); spin_unlock(&se_sess->sess_cmd_lock); + target_free_cmd_mem(se_cmd); complete(&se_cmd->cmd_wait_comp); return; } - list_del(&se_cmd->se_cmd_list); + list_del_init(&se_cmd->se_cmd_list); spin_unlock(&se_sess->sess_cmd_lock); + target_free_cmd_mem(se_cmd); se_cmd->se_tfo->release_cmd(se_cmd); } @@ -2454,6 +2484,7 @@ int target_put_sess_cmd(struct se_cmd *se_cmd) struct se_session *se_sess = se_cmd->se_sess; if (!se_sess) { + target_free_cmd_mem(se_cmd); se_cmd->se_tfo->release_cmd(se_cmd); return 1; } @@ -2471,6 +2502,7 @@ void target_sess_cmd_list_set_waiting(struct se_session *se_sess) { struct se_cmd *se_cmd; unsigned long flags; + int rc; spin_lock_irqsave(&se_sess->sess_cmd_lock, flags); if (se_sess->sess_tearing_down) { @@ -2480,8 +2512,15 @@ void target_sess_cmd_list_set_waiting(struct se_session *se_sess) se_sess->sess_tearing_down = 1; list_splice_init(&se_sess->sess_cmd_list, &se_sess->sess_wait_list); - list_for_each_entry(se_cmd, &se_sess->sess_wait_list, se_cmd_list) - se_cmd->cmd_wait_set = 1; + list_for_each_entry(se_cmd, &se_sess->sess_wait_list, se_cmd_list) { + rc = kref_get_unless_zero(&se_cmd->cmd_kref); + if (rc) { + se_cmd->cmd_wait_set = 1; + spin_lock(&se_cmd->t_state_lock); + se_cmd->transport_state |= CMD_T_FABRIC_STOP; + spin_unlock(&se_cmd->t_state_lock); + } + } spin_unlock_irqrestore(&se_sess->sess_cmd_lock, flags); } @@ -2494,15 +2533,25 @@ void target_wait_for_sess_cmds(struct se_session *se_sess) { struct se_cmd *se_cmd, *tmp_cmd; unsigned long flags; + bool tas; list_for_each_entry_safe(se_cmd, tmp_cmd, &se_sess->sess_wait_list, se_cmd_list) { - list_del(&se_cmd->se_cmd_list); + list_del_init(&se_cmd->se_cmd_list); pr_debug("Waiting for se_cmd: %p t_state: %d, fabric state:" " %d\n", se_cmd, se_cmd->t_state, se_cmd->se_tfo->get_cmd_state(se_cmd)); + spin_lock_irqsave(&se_cmd->t_state_lock, flags); + tas = (se_cmd->transport_state & CMD_T_TAS); + spin_unlock_irqrestore(&se_cmd->t_state_lock, flags); + + if (!target_put_sess_cmd(se_cmd)) { + if (tas) + target_put_sess_cmd(se_cmd); + } + wait_for_completion(&se_cmd->cmd_wait_comp); pr_debug("After cmd_wait_comp: se_cmd: %p t_state: %d" " fabric state: %d\n", se_cmd, se_cmd->t_state, @@ -2545,34 +2594,38 @@ int transport_clear_lun_ref(struct se_lun *lun) return 0; } -/** - * transport_wait_for_tasks - wait for completion to occur - * @cmd: command to wait - * - * Called from frontend fabric context to wait for storage engine - * to pause and/or release frontend generated struct se_cmd. - */ -bool transport_wait_for_tasks(struct se_cmd *cmd) +static bool +__transport_wait_for_tasks(struct se_cmd *cmd, bool fabric_stop, + bool *aborted, bool *tas, unsigned long *flags) + __releases(&cmd->t_state_lock) + __acquires(&cmd->t_state_lock) { - unsigned long flags; - spin_lock_irqsave(&cmd->t_state_lock, flags); + assert_spin_locked(&cmd->t_state_lock); + WARN_ON_ONCE(!irqs_disabled()); + + if (fabric_stop) + cmd->transport_state |= CMD_T_FABRIC_STOP; + + if (cmd->transport_state & CMD_T_ABORTED) + *aborted = true; + + if (cmd->transport_state & CMD_T_TAS) + *tas = true; + if (!(cmd->se_cmd_flags & SCF_SE_LUN_CMD) && - !(cmd->se_cmd_flags & SCF_SCSI_TMR_CDB)) { - spin_unlock_irqrestore(&cmd->t_state_lock, flags); + !(cmd->se_cmd_flags & SCF_SCSI_TMR_CDB)) return false; - } if (!(cmd->se_cmd_flags & SCF_SUPPORTED_SAM_OPCODE) && - !(cmd->se_cmd_flags & SCF_SCSI_TMR_CDB)) { - spin_unlock_irqrestore(&cmd->t_state_lock, flags); + !(cmd->se_cmd_flags & SCF_SCSI_TMR_CDB)) return false; - } - if (!(cmd->transport_state & CMD_T_ACTIVE)) { - spin_unlock_irqrestore(&cmd->t_state_lock, flags); + if (!(cmd->transport_state & CMD_T_ACTIVE)) + return false; + + if (fabric_stop && *aborted) return false; - } cmd->transport_state |= CMD_T_STOP; @@ -2581,20 +2634,37 @@ bool transport_wait_for_tasks(struct se_cmd *cmd) cmd, cmd->se_tfo->get_task_tag(cmd), cmd->se_tfo->get_cmd_state(cmd), cmd->t_state); - spin_unlock_irqrestore(&cmd->t_state_lock, flags); + spin_unlock_irqrestore(&cmd->t_state_lock, *flags); wait_for_completion(&cmd->t_transport_stop_comp); - spin_lock_irqsave(&cmd->t_state_lock, flags); + spin_lock_irqsave(&cmd->t_state_lock, *flags); cmd->transport_state &= ~(CMD_T_ACTIVE | CMD_T_STOP); pr_debug("wait_for_tasks: Stopped wait_for_completion(" "&cmd->t_transport_stop_comp) for ITT: 0x%08x\n", cmd->se_tfo->get_task_tag(cmd)); + return true; +} + +/** + * transport_wait_for_tasks - wait for completion to occur + * @cmd: command to wait + * + * Called from frontend fabric context to wait for storage engine + * to pause and/or release frontend generated struct se_cmd. + */ +bool transport_wait_for_tasks(struct se_cmd *cmd) +{ + unsigned long flags; + bool ret, aborted = false, tas = false; + + spin_lock_irqsave(&cmd->t_state_lock, flags); + ret = __transport_wait_for_tasks(cmd, false, &aborted, &tas, &flags); spin_unlock_irqrestore(&cmd->t_state_lock, flags); - return true; + return ret; } EXPORT_SYMBOL(transport_wait_for_tasks); @@ -2880,8 +2950,13 @@ after_reason: } EXPORT_SYMBOL(transport_send_check_condition_and_sense); -int transport_check_aborted_status(struct se_cmd *cmd, int send_status) +static int __transport_check_aborted_status(struct se_cmd *cmd, int send_status) + __releases(&cmd->t_state_lock) + __acquires(&cmd->t_state_lock) { + assert_spin_locked(&cmd->t_state_lock); + WARN_ON_ONCE(!irqs_disabled()); + if (!(cmd->transport_state & CMD_T_ABORTED)) return 0; @@ -2889,19 +2964,37 @@ int transport_check_aborted_status(struct se_cmd *cmd, int send_status) * If cmd has been aborted but either no status is to be sent or it has * already been sent, just return */ - if (!send_status || !(cmd->se_cmd_flags & SCF_SEND_DELAYED_TAS)) + if (!send_status || !(cmd->se_cmd_flags & SCF_SEND_DELAYED_TAS)) { + if (send_status) + cmd->se_cmd_flags |= SCF_SEND_DELAYED_TAS; return 1; + } - pr_debug("Sending delayed SAM_STAT_TASK_ABORTED status for CDB: 0x%02x ITT: 0x%08x\n", - cmd->t_task_cdb[0], cmd->se_tfo->get_task_tag(cmd)); + pr_debug("Sending delayed SAM_STAT_TASK_ABORTED status for CDB:" + " 0x%02x ITT: 0x%08x\n", cmd->t_task_cdb[0], + cmd->se_tfo->get_task_tag(cmd)); cmd->se_cmd_flags &= ~SCF_SEND_DELAYED_TAS; cmd->scsi_status = SAM_STAT_TASK_ABORTED; trace_target_cmd_complete(cmd); + + spin_unlock_irq(&cmd->t_state_lock); cmd->se_tfo->queue_status(cmd); + spin_lock_irq(&cmd->t_state_lock); return 1; } + +int transport_check_aborted_status(struct se_cmd *cmd, int send_status) +{ + int ret; + + spin_lock_irq(&cmd->t_state_lock); + ret = __transport_check_aborted_status(cmd, send_status); + spin_unlock_irq(&cmd->t_state_lock); + + return ret; +} EXPORT_SYMBOL(transport_check_aborted_status); void transport_send_task_abort(struct se_cmd *cmd) @@ -2923,11 +3016,17 @@ void transport_send_task_abort(struct se_cmd *cmd) */ if (cmd->data_direction == DMA_TO_DEVICE) { if (cmd->se_tfo->write_pending_status(cmd) != 0) { - cmd->transport_state |= CMD_T_ABORTED; + spin_lock_irqsave(&cmd->t_state_lock, flags); + if (cmd->se_cmd_flags & SCF_SEND_DELAYED_TAS) { + spin_unlock_irqrestore(&cmd->t_state_lock, flags); + goto send_abort; + } cmd->se_cmd_flags |= SCF_SEND_DELAYED_TAS; + spin_unlock_irqrestore(&cmd->t_state_lock, flags); return; } } +send_abort: cmd->scsi_status = SAM_STAT_TASK_ABORTED; transport_lun_remove_cmd(cmd); |