From 209fae14fabfd48525e5630bebbbd4ca15090c60 Mon Sep 17 00:00:00 2001 From: Dan Williams Date: Mon, 13 Jun 2011 17:39:44 -0700 Subject: [PATCH] isci: atomic device lookup and reference counting We have unsafe references to remote devices that are notified to disappear at lldd_dev_gone. In order to clean this up we need a single canonical source for device lookups and stable references once a lookup succeeds. Towards that end guarantee that domain_device.lldd_dev is NULL as soon as we start the process of stopping a device. Any code path that wants to safely lookup a remote device must do so through task->dev->lldd_dev (isci_lookup_device()). For in-flight references outside of scic_lock we need reference counting to ensure that the device is not recycled before we are done with it. Simplify device back references to just scic_sds_request.target_device which is now the only permissible internal reference that is maintained relative to the reference count. There were two occasions where we wanted new i/o's to be treated as SAS_TASK_UNDELIVERED but where the domain_dev->lldd_dev link is still intact. Introduce a 'gone' flag to prevent i/o while waiting for libsas to take action on the port down event. One 'core' leftover is that we currently call scic_remote_device_destruct() from isci_remote_device_deconstruct() which is called when the 'core' says the device is stopped. It would be more natural for the final put to trigger isci_remote_device_deconstruct() but this implementation is deferred as it requires other changes. Signed-off-by: Dan Williams --- drivers/scsi/isci/host.c | 4 +- drivers/scsi/isci/port.c | 3 +- drivers/scsi/isci/remote_device.c | 80 ++++++----- drivers/scsi/isci/remote_device.h | 23 +++ drivers/scsi/isci/request.c | 60 +++----- drivers/scsi/isci/request.h | 7 +- drivers/scsi/isci/sata.c | 7 +- drivers/scsi/isci/task.c | 231 ++++++++++++------------------ drivers/scsi/isci/task.h | 9 +- 9 files changed, 187 insertions(+), 237 deletions(-) diff --git a/drivers/scsi/isci/host.c b/drivers/scsi/isci/host.c index ae9edae1d24..40f35fad244 100644 --- a/drivers/scsi/isci/host.c +++ b/drivers/scsi/isci/host.c @@ -1327,8 +1327,8 @@ void isci_host_deinit(struct isci_host *ihost) struct isci_remote_device *idev, *d; list_for_each_entry_safe(idev, d, &iport->remote_dev_list, node) { - isci_remote_device_change_state(idev, isci_stopping); - isci_remote_device_stop(ihost, idev); + if (test_bit(IDEV_ALLOCATED, &idev->flags)) + isci_remote_device_stop(ihost, idev); } } diff --git a/drivers/scsi/isci/port.c b/drivers/scsi/isci/port.c index fb66e30da07..5f4a4e3954d 100644 --- a/drivers/scsi/isci/port.c +++ b/drivers/scsi/isci/port.c @@ -321,8 +321,7 @@ static void isci_port_link_down(struct isci_host *isci_host, dev_dbg(&isci_host->pdev->dev, "%s: isci_device = %p\n", __func__, isci_device); - isci_remote_device_change_state(isci_device, - isci_stopping); + set_bit(IDEV_GONE, &isci_device->flags); } } isci_port_change_state(isci_port, isci_stopping); diff --git a/drivers/scsi/isci/remote_device.c b/drivers/scsi/isci/remote_device.c index 45592ad33c3..ab5f9868e4e 100644 --- a/drivers/scsi/isci/remote_device.c +++ b/drivers/scsi/isci/remote_device.c @@ -94,7 +94,7 @@ static void isci_remote_device_not_ready(struct isci_host *ihost, "%s: isci_device = %p\n", __func__, idev); if (reason == SCIC_REMOTE_DEVICE_NOT_READY_STOP_REQUESTED) - isci_remote_device_change_state(idev, isci_stopping); + set_bit(IDEV_GONE, &idev->flags); else /* device ready is actually a "not ready for io" state. */ isci_remote_device_change_state(idev, isci_ready); @@ -449,8 +449,10 @@ static void scic_sds_remote_device_start_request(struct scic_sds_remote_device * /* cleanup requests that failed after starting on the port */ if (status != SCI_SUCCESS) scic_sds_port_complete_io(sci_port, sci_dev, sci_req); - else + else { + kref_get(&sci_dev_to_idev(sci_dev)->kref); scic_sds_remote_device_increment_request_count(sci_dev); + } } enum sci_status scic_sds_remote_device_start_io(struct scic_sds_controller *scic, @@ -656,6 +658,8 @@ enum sci_status scic_sds_remote_device_complete_io(struct scic_sds_controller *s "%s: Port:0x%p Device:0x%p Request:0x%p Status:0x%x " "could not complete\n", __func__, sci_port, sci_dev, sci_req, status); + else + isci_put_device(sci_dev_to_idev(sci_dev)); return status; } @@ -860,23 +864,11 @@ static void isci_remote_device_deconstruct(struct isci_host *ihost, struct isci_ * here should go through isci_remote_device_nuke_requests. * If we hit this condition, we will need a way to complete * io requests in process */ - while (!list_empty(&idev->reqs_in_process)) { - - dev_err(&ihost->pdev->dev, - "%s: ** request list not empty! **\n", __func__); - BUG(); - } + BUG_ON(!list_empty(&idev->reqs_in_process)); scic_remote_device_destruct(&idev->sci); - idev->domain_dev->lldd_dev = NULL; - idev->domain_dev = NULL; - idev->isci_port = NULL; list_del_init(&idev->node); - - clear_bit(IDEV_START_PENDING, &idev->flags); - clear_bit(IDEV_STOP_PENDING, &idev->flags); - clear_bit(IDEV_EH, &idev->flags); - wake_up(&ihost->eventq); + isci_put_device(idev); } /** @@ -1314,6 +1306,22 @@ isci_remote_device_alloc(struct isci_host *ihost, struct isci_port *iport) return idev; } +void isci_remote_device_release(struct kref *kref) +{ + struct isci_remote_device *idev = container_of(kref, typeof(*idev), kref); + struct isci_host *ihost = idev->isci_port->isci_host; + + idev->domain_dev = NULL; + idev->isci_port = NULL; + clear_bit(IDEV_START_PENDING, &idev->flags); + clear_bit(IDEV_STOP_PENDING, &idev->flags); + clear_bit(IDEV_GONE, &idev->flags); + clear_bit(IDEV_EH, &idev->flags); + smp_mb__before_clear_bit(); + clear_bit(IDEV_ALLOCATED, &idev->flags); + wake_up(&ihost->eventq); +} + /** * isci_remote_device_stop() - This function is called internally to stop the * remote device. @@ -1330,7 +1338,11 @@ enum sci_status isci_remote_device_stop(struct isci_host *ihost, struct isci_rem dev_dbg(&ihost->pdev->dev, "%s: isci_device = %p\n", __func__, idev); + spin_lock_irqsave(&ihost->scic_lock, flags); + idev->domain_dev->lldd_dev = NULL; /* disable new lookups */ + set_bit(IDEV_GONE, &idev->flags); isci_remote_device_change_state(idev, isci_stopping); + spin_unlock_irqrestore(&ihost->scic_lock, flags); /* Kill all outstanding requests. */ isci_remote_device_nuke_requests(ihost, idev); @@ -1342,14 +1354,10 @@ enum sci_status isci_remote_device_stop(struct isci_host *ihost, struct isci_rem spin_unlock_irqrestore(&ihost->scic_lock, flags); /* Wait for the stop complete callback. */ - if (status == SCI_SUCCESS) { + if (WARN_ONCE(status != SCI_SUCCESS, "failed to stop device\n")) + /* nothing to wait for */; + else wait_for_device_stop(ihost, idev); - clear_bit(IDEV_ALLOCATED, &idev->flags); - } - - dev_dbg(&ihost->pdev->dev, - "%s: idev = %p - after completion wait\n", - __func__, idev); return status; } @@ -1416,39 +1424,33 @@ int isci_remote_device_found(struct domain_device *domain_dev) if (!isci_device) return -ENODEV; + kref_init(&isci_device->kref); INIT_LIST_HEAD(&isci_device->node); - domain_dev->lldd_dev = isci_device; + + spin_lock_irq(&isci_host->scic_lock); isci_device->domain_dev = domain_dev; isci_device->isci_port = isci_port; isci_remote_device_change_state(isci_device, isci_starting); - - - spin_lock_irq(&isci_host->scic_lock); list_add_tail(&isci_device->node, &isci_port->remote_dev_list); set_bit(IDEV_START_PENDING, &isci_device->flags); status = isci_remote_device_construct(isci_port, isci_device); - spin_unlock_irq(&isci_host->scic_lock); dev_dbg(&isci_host->pdev->dev, "%s: isci_device = %p\n", __func__, isci_device); - if (status != SCI_SUCCESS) { - - spin_lock_irq(&isci_host->scic_lock); - isci_remote_device_deconstruct( - isci_host, - isci_device - ); - spin_unlock_irq(&isci_host->scic_lock); - return -ENODEV; - } + if (status == SCI_SUCCESS) { + /* device came up, advertise it to the world */ + domain_dev->lldd_dev = isci_device; + } else + isci_put_device(isci_device); + spin_unlock_irq(&isci_host->scic_lock); /* wait for the device ready callback. */ wait_for_device_start(isci_host, isci_device); - return 0; + return status == SCI_SUCCESS ? 0 : -ENODEV; } /** * isci_device_is_reset_pending() - This function will check if there is any diff --git a/drivers/scsi/isci/remote_device.h b/drivers/scsi/isci/remote_device.h index 2b6a5bb7bd6..05842b5f1e3 100644 --- a/drivers/scsi/isci/remote_device.h +++ b/drivers/scsi/isci/remote_device.h @@ -56,6 +56,7 @@ #ifndef _ISCI_REMOTE_DEVICE_H_ #define _ISCI_REMOTE_DEVICE_H_ #include +#include #include "scu_remote_node_context.h" #include "remote_node_context.h" #include "port.h" @@ -134,7 +135,9 @@ struct isci_remote_device { #define IDEV_STOP_PENDING 1 #define IDEV_ALLOCATED 2 #define IDEV_EH 3 + #define IDEV_GONE 4 unsigned long flags; + struct kref kref; struct isci_port *isci_port; struct domain_device *domain_dev; struct list_head node; @@ -145,6 +148,26 @@ struct isci_remote_device { #define ISCI_REMOTE_DEVICE_START_TIMEOUT 5000 +/* device reference routines must be called under scic_lock */ +static inline struct isci_remote_device *isci_lookup_device(struct domain_device *dev) +{ + struct isci_remote_device *idev = dev->lldd_dev; + + if (idev && !test_bit(IDEV_GONE, &idev->flags)) { + kref_get(&idev->kref); + return idev; + } + + return NULL; +} + +void isci_remote_device_release(struct kref *kref); +static inline void isci_put_device(struct isci_remote_device *idev) +{ + if (idev) + kref_put(&idev->kref, isci_remote_device_release); +} + enum sci_status isci_remote_device_stop(struct isci_host *ihost, struct isci_remote_device *idev); void isci_remote_device_nuke_requests(struct isci_host *ihost, diff --git a/drivers/scsi/isci/request.c b/drivers/scsi/isci/request.c index f0813d076c5..fd6314abeb0 100644 --- a/drivers/scsi/isci/request.c +++ b/drivers/scsi/isci/request.c @@ -2313,7 +2313,7 @@ static void isci_request_set_open_reject_status( * none. */ static void isci_request_handle_controller_specific_errors( - struct isci_remote_device *isci_device, + struct isci_remote_device *idev, struct isci_request *request, struct sas_task *task, enum service_response *response_ptr, @@ -2353,8 +2353,7 @@ static void isci_request_handle_controller_specific_errors( * that we ignore the quiesce state, since we are * concerned about the actual device state. */ - if ((isci_device->status == isci_stopping) || - (isci_device->status == isci_stopped)) + if (!idev) *status_ptr = SAS_DEVICE_UNKNOWN; else *status_ptr = SAS_ABORTED_TASK; @@ -2367,8 +2366,7 @@ static void isci_request_handle_controller_specific_errors( /* Task in the target is not done. */ *response_ptr = SAS_TASK_UNDELIVERED; - if ((isci_device->status == isci_stopping) || - (isci_device->status == isci_stopped)) + if (!idev) *status_ptr = SAS_DEVICE_UNKNOWN; else *status_ptr = SAM_STAT_TASK_ABORTED; @@ -2399,8 +2397,7 @@ static void isci_request_handle_controller_specific_errors( * that we ignore the quiesce state, since we are * concerned about the actual device state. */ - if ((isci_device->status == isci_stopping) || - (isci_device->status == isci_stopped)) + if (!idev) *status_ptr = SAS_DEVICE_UNKNOWN; else *status_ptr = SAS_ABORTED_TASK; @@ -2629,7 +2626,7 @@ static void isci_request_io_request_complete(struct isci_host *isci_host, struct ssp_response_iu *resp_iu; void *resp_buf; unsigned long task_flags; - struct isci_remote_device *isci_device = request->isci_device; + struct isci_remote_device *idev = isci_lookup_device(task->dev); enum service_response response = SAS_TASK_UNDELIVERED; enum exec_status status = SAS_ABORTED_TASK; enum isci_request_status request_status; @@ -2672,9 +2669,7 @@ static void isci_request_io_request_complete(struct isci_host *isci_host, * that we ignore the quiesce state, since we are * concerned about the actual device state. */ - if ((isci_device->status == isci_stopping) - || (isci_device->status == isci_stopped) - ) + if (!idev) status = SAS_DEVICE_UNKNOWN; else status = SAS_ABORTED_TASK; @@ -2697,8 +2692,7 @@ static void isci_request_io_request_complete(struct isci_host *isci_host, request->complete_in_target = true; response = SAS_TASK_UNDELIVERED; - if ((isci_device->status == isci_stopping) || - (isci_device->status == isci_stopped)) + if (!idev) /* The device has been /is being stopped. Note that * we ignore the quiesce state, since we are * concerned about the actual device state. @@ -2728,8 +2722,7 @@ static void isci_request_io_request_complete(struct isci_host *isci_host, * that we ignore the quiesce state, since we are * concerned about the actual device state. */ - if ((isci_device->status == isci_stopping) || - (isci_device->status == isci_stopped)) + if (!idev) status = SAS_DEVICE_UNKNOWN; else status = SAS_ABORTED_TASK; @@ -2861,8 +2854,7 @@ static void isci_request_io_request_complete(struct isci_host *isci_host, * that we ignore the quiesce state, since we are * concerned about the actual device state. */ - if ((isci_device->status == isci_stopping) || - (isci_device->status == isci_stopped)) + if (!idev) status = SAS_DEVICE_UNKNOWN; else status = SAS_ABORTED_TASK; @@ -2873,7 +2865,7 @@ static void isci_request_io_request_complete(struct isci_host *isci_host, case SCI_FAILURE_CONTROLLER_SPECIFIC_IO_ERR: isci_request_handle_controller_specific_errors( - isci_device, request, task, &response, &status, + idev, request, task, &response, &status, &complete_to_host); break; @@ -2902,8 +2894,7 @@ static void isci_request_io_request_complete(struct isci_host *isci_host, /* Fail the I/O so it can be retried. */ response = SAS_TASK_UNDELIVERED; - if ((isci_device->status == isci_stopping) || - (isci_device->status == isci_stopped)) + if (!idev) status = SAS_DEVICE_UNKNOWN; else status = SAS_ABORTED_TASK; @@ -2926,8 +2917,7 @@ static void isci_request_io_request_complete(struct isci_host *isci_host, * that we ignore the quiesce state, since we are * concerned about the actual device state. */ - if ((isci_device->status == isci_stopping) || - (isci_device->status == isci_stopped)) + if (!idev) status = SAS_DEVICE_UNKNOWN; else status = SAS_ABORTED_TASK; @@ -2953,8 +2943,10 @@ static void isci_request_io_request_complete(struct isci_host *isci_host, /* complete the io request to the core. */ scic_controller_complete_io(&isci_host->sci, - &isci_device->sci, + request->sci.target_device, &request->sci); + isci_put_device(idev); + /* set terminated handle so it cannot be completed or * terminated again, and to cause any calls into abort * task to recognize the already completed case. @@ -3511,7 +3503,6 @@ static enum sci_status isci_io_request_build( } static struct isci_request *isci_request_alloc_core(struct isci_host *ihost, - struct isci_remote_device *idev, gfp_t gfp_flags) { dma_addr_t handle; @@ -3528,7 +3519,6 @@ static struct isci_request *isci_request_alloc_core(struct isci_host *ihost, spin_lock_init(&ireq->state_lock); ireq->request_daddr = handle; ireq->isci_host = ihost; - ireq->isci_device = idev; ireq->io_request_completion = NULL; ireq->terminated = false; @@ -3546,12 +3536,11 @@ static struct isci_request *isci_request_alloc_core(struct isci_host *ihost, static struct isci_request *isci_request_alloc_io(struct isci_host *ihost, struct sas_task *task, - struct isci_remote_device *idev, gfp_t gfp_flags) { struct isci_request *ireq; - ireq = isci_request_alloc_core(ihost, idev, gfp_flags); + ireq = isci_request_alloc_core(ihost, gfp_flags); if (ireq) { ireq->ttype_ptr.io_task_ptr = task; ireq->ttype = io_task; @@ -3562,12 +3551,11 @@ static struct isci_request *isci_request_alloc_io(struct isci_host *ihost, struct isci_request *isci_request_alloc_tmf(struct isci_host *ihost, struct isci_tmf *isci_tmf, - struct isci_remote_device *idev, gfp_t gfp_flags) { struct isci_request *ireq; - ireq = isci_request_alloc_core(ihost, idev, gfp_flags); + ireq = isci_request_alloc_core(ihost, gfp_flags); if (ireq) { ireq->ttype_ptr.tmf_task_ptr = isci_tmf; ireq->ttype = tmf_task; @@ -3575,21 +3563,16 @@ struct isci_request *isci_request_alloc_tmf(struct isci_host *ihost, return ireq; } -int isci_request_execute(struct isci_host *ihost, struct sas_task *task, - gfp_t gfp_flags) +int isci_request_execute(struct isci_host *ihost, struct isci_remote_device *idev, + struct sas_task *task, gfp_t gfp_flags) { enum sci_status status = SCI_FAILURE_UNSUPPORTED_PROTOCOL; - struct scic_sds_remote_device *sci_dev; - struct isci_remote_device *idev; struct isci_request *ireq; unsigned long flags; int ret = 0; - idev = task->dev->lldd_dev; - sci_dev = &idev->sci; - /* do common allocation and init of request object. */ - ireq = isci_request_alloc_io(ihost, task, idev, gfp_flags); + ireq = isci_request_alloc_io(ihost, task, gfp_flags); if (!ireq) goto out; @@ -3605,8 +3588,7 @@ int isci_request_execute(struct isci_host *ihost, struct sas_task *task, spin_lock_irqsave(&ihost->scic_lock, flags); /* send the request, let the core assign the IO TAG. */ - status = scic_controller_start_io(&ihost->sci, sci_dev, - &ireq->sci, + status = scic_controller_start_io(&ihost->sci, &idev->sci, &ireq->sci, SCI_CONTROLLER_INVALID_IO_TAG); if (status != SCI_SUCCESS && status != SCI_FAILURE_REMOTE_DEVICE_RESET_REQUIRED) { diff --git a/drivers/scsi/isci/request.h b/drivers/scsi/isci/request.h index 8de2542f081..9bb7c36257f 100644 --- a/drivers/scsi/isci/request.h +++ b/drivers/scsi/isci/request.h @@ -285,7 +285,6 @@ struct isci_request { struct isci_tmf *tmf_task_ptr; /* When ttype==tmf_task */ } ttype_ptr; struct isci_host *isci_host; - struct isci_remote_device *isci_device; /* For use in the requests_to_{complete|abort} lists: */ struct list_head completed_node; /* For use in the reqs_in_process list: */ @@ -681,12 +680,10 @@ static inline void isci_request_free(struct isci_host *isci_host, struct isci_request *isci_request_alloc_tmf(struct isci_host *ihost, struct isci_tmf *isci_tmf, - struct isci_remote_device *idev, gfp_t gfp_flags); -int isci_request_execute(struct isci_host *isci_host, - struct sas_task *task, - gfp_t gfp_flags); +int isci_request_execute(struct isci_host *ihost, struct isci_remote_device *idev, + struct sas_task *task, gfp_t gfp_flags); /** * isci_request_unmap_sgl() - This function unmaps the DMA address of a given diff --git a/drivers/scsi/isci/sata.c b/drivers/scsi/isci/sata.c index b9b9271d473..e7ce4692446 100644 --- a/drivers/scsi/isci/sata.c +++ b/drivers/scsi/isci/sata.c @@ -213,11 +213,10 @@ int isci_task_send_lu_reset_sata( /* Send the soft reset to the target */ #define ISCI_SRST_TIMEOUT_MS 25000 /* 25 second timeout. */ - isci_task_build_tmf(&tmf, isci_device, isci_tmf_sata_srst_high, - NULL, NULL - ); + isci_task_build_tmf(&tmf, isci_tmf_sata_srst_high, NULL, NULL); - ret = isci_task_execute_tmf(isci_host, &tmf, ISCI_SRST_TIMEOUT_MS); + ret = isci_task_execute_tmf(isci_host, isci_device, &tmf, + ISCI_SRST_TIMEOUT_MS); if (ret != TMF_RESP_FUNC_COMPLETE) { dev_warn(&isci_host->pdev->dev, diff --git a/drivers/scsi/isci/task.c b/drivers/scsi/isci/task.c index ded81cd1a78..dd5e9de1ffb 100644 --- a/drivers/scsi/isci/task.c +++ b/drivers/scsi/isci/task.c @@ -146,7 +146,7 @@ static void isci_task_refuse(struct isci_host *ihost, struct sas_task *task, int isci_task_execute_task(struct sas_task *task, int num, gfp_t gfp_flags) { struct isci_host *ihost = dev_to_ihost(task->dev); - struct isci_remote_device *device; + struct isci_remote_device *idev; unsigned long flags; int ret; enum sci_status status; @@ -166,11 +166,12 @@ int isci_task_execute_task(struct sas_task *task, int num, gfp_t gfp_flags) dev_dbg(&ihost->pdev->dev, "task = %p, num = %d; dev = %p; cmd = %p\n", task, num, task->dev, task->uldd_task); + spin_lock_irqsave(&ihost->scic_lock, flags); + idev = isci_lookup_device(task->dev); + spin_unlock_irqrestore(&ihost->scic_lock, flags); - device = task->dev->lldd_dev; - - if (device) - device_status = device->status; + if (idev) + device_status = idev->status; else device_status = isci_freed; @@ -188,7 +189,7 @@ int isci_task_execute_task(struct sas_task *task, int num, gfp_t gfp_flags) __func__, task, isci_host_get_state(ihost), - device, + idev, device_status); if (device_status == isci_ready) { @@ -225,7 +226,7 @@ int isci_task_execute_task(struct sas_task *task, int num, gfp_t gfp_flags) spin_unlock_irqrestore(&task->task_state_lock, flags); /* build and send the request. */ - status = isci_request_execute(ihost, task, gfp_flags); + status = isci_request_execute(ihost, idev, task, gfp_flags); if (status != SCI_SUCCESS) { @@ -248,33 +249,31 @@ int isci_task_execute_task(struct sas_task *task, int num, gfp_t gfp_flags) } } } + isci_put_device(idev); } return 0; } static struct isci_request *isci_task_request_build(struct isci_host *ihost, + struct isci_remote_device *idev, struct isci_tmf *isci_tmf) { - struct scic_sds_remote_device *sci_dev; enum sci_status status = SCI_FAILURE; struct isci_request *ireq = NULL; - struct isci_remote_device *idev; struct domain_device *dev; dev_dbg(&ihost->pdev->dev, "%s: isci_tmf = %p\n", __func__, isci_tmf); - idev = isci_tmf->device; - sci_dev = &idev->sci; dev = idev->domain_dev; /* do common allocation and init of request object. */ - ireq = isci_request_alloc_tmf(ihost, isci_tmf, idev, GFP_ATOMIC); + ireq = isci_request_alloc_tmf(ihost, isci_tmf, GFP_ATOMIC); if (!ireq) return NULL; /* let the core do it's construct. */ - status = scic_task_request_construct(&ihost->sci, sci_dev, + status = scic_task_request_construct(&ihost->sci, &idev->sci, SCI_CONTROLLER_INVALID_IO_TAG, &ireq->sci); @@ -309,25 +308,13 @@ static struct isci_request *isci_task_request_build(struct isci_host *ihost, return ireq; } -/** - * isci_task_execute_tmf() - This function builds and sends a task request, - * then waits for the completion. - * @isci_host: This parameter specifies the ISCI host object - * @tmf: This parameter is the pointer to the task management structure for - * this request. - * @timeout_ms: This parameter specifies the timeout period for the task - * management request. - * - * TMF_RESP_FUNC_COMPLETE on successful completion of the TMF (this includes - * error conditions reported in the IU status), or TMF_RESP_FUNC_FAILED. - */ -int isci_task_execute_tmf(struct isci_host *ihost, struct isci_tmf *tmf, - unsigned long timeout_ms) +int isci_task_execute_tmf(struct isci_host *ihost, + struct isci_remote_device *isci_device, + struct isci_tmf *tmf, unsigned long timeout_ms) { DECLARE_COMPLETION_ONSTACK(completion); enum sci_task_status status = SCI_TASK_FAILURE; struct scic_sds_remote_device *sci_device; - struct isci_remote_device *isci_device = tmf->device; struct isci_request *ireq; int ret = TMF_RESP_FUNC_FAILED; unsigned long flags; @@ -352,7 +339,7 @@ int isci_task_execute_tmf(struct isci_host *ihost, struct isci_tmf *tmf, /* Assign the pointer to the TMF's completion kernel wait structure. */ tmf->complete = &completion; - ireq = isci_task_request_build(ihost, tmf); + ireq = isci_task_request_build(ihost, isci_device, tmf); if (!ireq) { dev_warn(&ihost->pdev->dev, "%s: isci_task_request_build failed\n", @@ -399,10 +386,9 @@ int isci_task_execute_tmf(struct isci_host *ihost, struct isci_tmf *tmf, if (tmf->cb_state_func != NULL) tmf->cb_state_func(isci_tmf_timed_out, tmf, tmf->cb_data); - status = scic_controller_terminate_request( - &ireq->isci_host->sci, - &ireq->isci_device->sci, - &ireq->sci); + status = scic_controller_terminate_request(&ihost->sci, + &isci_device->sci, + &ireq->sci); spin_unlock_irqrestore(&ihost->scic_lock, flags); } @@ -437,65 +423,32 @@ int isci_task_execute_tmf(struct isci_host *ihost, struct isci_tmf *tmf, void isci_task_build_tmf( struct isci_tmf *tmf, - struct isci_remote_device *isci_device, enum isci_tmf_function_codes code, void (*tmf_sent_cb)(enum isci_tmf_cb_state, struct isci_tmf *, void *), void *cb_data) { - dev_dbg(&isci_device->isci_port->isci_host->pdev->dev, - "%s: isci_device = %p\n", __func__, isci_device); - memset(tmf, 0, sizeof(*tmf)); - tmf->device = isci_device; tmf->tmf_code = code; - tmf->cb_state_func = tmf_sent_cb; tmf->cb_data = cb_data; } static void isci_task_build_abort_task_tmf( struct isci_tmf *tmf, - struct isci_remote_device *isci_device, enum isci_tmf_function_codes code, void (*tmf_sent_cb)(enum isci_tmf_cb_state, struct isci_tmf *, void *), struct isci_request *old_request) { - isci_task_build_tmf(tmf, isci_device, code, tmf_sent_cb, + isci_task_build_tmf(tmf, code, tmf_sent_cb, (void *)old_request); tmf->io_tag = old_request->io_tag; } -static struct isci_request *isci_task_get_request_from_task( - struct sas_task *task, - struct isci_remote_device **isci_device) -{ - - struct isci_request *request = NULL; - unsigned long flags; - - spin_lock_irqsave(&task->task_state_lock, flags); - - request = task->lldd_task; - - /* If task is already done, the request isn't valid */ - if (!(task->task_state_flags & SAS_TASK_STATE_DONE) && - (task->task_state_flags & SAS_TASK_AT_INITIATOR) && - (request != NULL)) { - - if (isci_device != NULL) - *isci_device = request->isci_device; - } - - spin_unlock_irqrestore(&task->task_state_lock, flags); - - return request; -} - /** * isci_task_validate_request_to_abort() - This function checks the given I/O * against the "started" state. If the request is still "started", it's @@ -858,11 +811,10 @@ static int isci_task_send_lu_reset_sas( * value is "TMF_RESP_FUNC_COMPLETE", or the request timed-out (or * was otherwise unable to be executed ("TMF_RESP_FUNC_FAILED"). */ - isci_task_build_tmf(&tmf, isci_device, isci_tmf_ssp_lun_reset, NULL, - NULL); + isci_task_build_tmf(&tmf, isci_tmf_ssp_lun_reset, NULL, NULL); #define ISCI_LU_RESET_TIMEOUT_MS 2000 /* 2 second timeout. */ - ret = isci_task_execute_tmf(isci_host, &tmf, ISCI_LU_RESET_TIMEOUT_MS); + ret = isci_task_execute_tmf(isci_host, isci_device, &tmf, ISCI_LU_RESET_TIMEOUT_MS); if (ret == TMF_RESP_FUNC_COMPLETE) dev_dbg(&isci_host->pdev->dev, @@ -888,33 +840,33 @@ static int isci_task_send_lu_reset_sas( int isci_task_lu_reset(struct domain_device *domain_device, u8 *lun) { struct isci_host *isci_host = dev_to_ihost(domain_device); - struct isci_remote_device *isci_device = NULL; + struct isci_remote_device *isci_device; + unsigned long flags; int ret; - bool device_stopping = false; - isci_device = domain_device->lldd_dev; + spin_lock_irqsave(&isci_host->scic_lock, flags); + isci_device = isci_lookup_device(domain_device); + spin_unlock_irqrestore(&isci_host->scic_lock, flags); dev_dbg(&isci_host->pdev->dev, "%s: domain_device=%p, isci_host=%p; isci_device=%p\n", __func__, domain_device, isci_host, isci_device); - if (isci_device != NULL) { - device_stopping = (isci_device->status == isci_stopping) - || (isci_device->status == isci_stopped); + if (isci_device) set_bit(IDEV_EH, &isci_device->flags); - } /* If there is a device reset pending on any request in the * device's list, fail this LUN reset request in order to * escalate to the device reset. */ - if (!isci_device || device_stopping || + if (!isci_device || isci_device_is_reset_pending(isci_host, isci_device)) { dev_warn(&isci_host->pdev->dev, "%s: No dev (%p), or " "RESET PENDING: domain_device=%p\n", __func__, isci_device, domain_device); - return TMF_RESP_FUNC_FAILED; + ret = TMF_RESP_FUNC_FAILED; + goto out; } /* Send the task management part of the reset. */ @@ -929,6 +881,8 @@ int isci_task_lu_reset(struct domain_device *domain_device, u8 *lun) isci_terminate_pending_requests(isci_host, isci_device); + out: + isci_put_device(isci_device); return ret; } @@ -1023,60 +977,54 @@ int isci_task_abort_task(struct sas_task *task) int ret = TMF_RESP_FUNC_FAILED; unsigned long flags; bool any_dev_reset = false; - bool device_stopping; /* Get the isci_request reference from the task. Note that * this check does not depend on the pending request list * in the device, because tasks driving resets may land here * after completion in the core. */ - old_request = isci_task_get_request_from_task(task, &isci_device); + spin_lock_irqsave(&isci_host->scic_lock, flags); + spin_lock(&task->task_state_lock); + + old_request = task->lldd_task; + + /* If task is already done, the request isn't valid */ + if (!(task->task_state_flags & SAS_TASK_STATE_DONE) && + (task->task_state_flags & SAS_TASK_AT_INITIATOR) && + old_request) + isci_device = isci_lookup_device(task->dev); + + spin_unlock(&task->task_state_lock); + spin_unlock_irqrestore(&isci_host->scic_lock, flags); dev_dbg(&isci_host->pdev->dev, "%s: task = %p\n", __func__, task); - /* Check if the device has been / is currently being removed. - * If so, no task management will be done, and the I/O will - * be terminated. - */ - device_stopping = (isci_device->status == isci_stopping) - || (isci_device->status == isci_stopped); + if (!isci_device || !old_request) + goto out; - /* XXX need to fix device lookup lifetime (needs to be done - * under scic_lock, among other things...), but for now assume - * the device is available like the above code - */ set_bit(IDEV_EH, &isci_device->flags); /* This version of the driver will fail abort requests for * SATA/STP. Failing the abort request this way will cause the * SCSI error handler thread to escalate to LUN reset */ - if (sas_protocol_ata(task->task_proto) && !device_stopping) { + if (sas_protocol_ata(task->task_proto)) { dev_warn(&isci_host->pdev->dev, " task %p is for a STP/SATA device;" " returning TMF_RESP_FUNC_FAILED\n" " to cause a LUN reset...\n", task); - return TMF_RESP_FUNC_FAILED; + goto out; } dev_dbg(&isci_host->pdev->dev, "%s: old_request == %p\n", __func__, old_request); - if (!device_stopping) - any_dev_reset = isci_device_is_reset_pending(isci_host,isci_device); + any_dev_reset = isci_device_is_reset_pending(isci_host,isci_device); spin_lock_irqsave(&task->task_state_lock, flags); - /* Don't do resets to stopping devices. */ - if (device_stopping) { - - task->task_state_flags &= ~SAS_TASK_NEED_DEV_RESET; - any_dev_reset = false; - - } else /* See if there is a pending device reset for this device. */ - any_dev_reset = any_dev_reset - || (task->task_state_flags & SAS_TASK_NEED_DEV_RESET); + any_dev_reset = any_dev_reset || (task->task_state_flags & SAS_TASK_NEED_DEV_RESET); /* If the extraction of the request reference from the task * failed, then the request has been completed (or if there is a @@ -1130,8 +1078,7 @@ int isci_task_abort_task(struct sas_task *task) "%s: abort task not needed for %p\n", __func__, task); } - - return ret; + goto out; } else spin_unlock_irqrestore(&task->task_state_lock, flags); @@ -1158,11 +1105,10 @@ int isci_task_abort_task(struct sas_task *task) "%s: device = %p; old_request %p already being aborted\n", __func__, isci_device, old_request); - - return TMF_RESP_FUNC_COMPLETE; + ret = TMF_RESP_FUNC_COMPLETE; + goto out; } if ((task->task_proto == SAS_PROTOCOL_SMP) - || device_stopping || old_request->complete_in_target ) { @@ -1170,10 +1116,9 @@ int isci_task_abort_task(struct sas_task *task) dev_dbg(&isci_host->pdev->dev, "%s: SMP request (%d)" - " or device is stopping (%d)" " or complete_in_target (%d), thus no TMF\n", __func__, (task->task_proto == SAS_PROTOCOL_SMP), - device_stopping, old_request->complete_in_target); + old_request->complete_in_target); /* Set the state on the task. */ isci_task_all_done(task); @@ -1185,15 +1130,14 @@ int isci_task_abort_task(struct sas_task *task) */ } else { /* Fill in the tmf stucture */ - isci_task_build_abort_task_tmf(&tmf, isci_device, - isci_tmf_ssp_task_abort, + isci_task_build_abort_task_tmf(&tmf, isci_tmf_ssp_task_abort, isci_abort_task_process_cb, old_request); spin_unlock_irqrestore(&isci_host->scic_lock, flags); #define ISCI_ABORT_TASK_TIMEOUT_MS 500 /* half second timeout. */ - ret = isci_task_execute_tmf(isci_host, &tmf, + ret = isci_task_execute_tmf(isci_host, isci_device, &tmf, ISCI_ABORT_TASK_TIMEOUT_MS); if (ret != TMF_RESP_FUNC_COMPLETE) @@ -1212,6 +1156,8 @@ int isci_task_abort_task(struct sas_task *task) /* Make sure we do not leave a reference to aborted_io_completion */ old_request->io_request_completion = NULL; + out: + isci_put_device(isci_device); return ret; } @@ -1305,7 +1251,6 @@ isci_task_request_complete(struct isci_host *ihost, struct isci_request *ireq, enum sci_task_status completion_status) { - struct isci_remote_device *idev = ireq->isci_device; struct isci_tmf *tmf = isci_request_access_tmf(ireq); struct completion *tmf_complete; struct scic_sds_request *sci_req = &ireq->sci; @@ -1332,7 +1277,7 @@ isci_task_request_complete(struct isci_host *ihost, /* PRINT_TMF( ((struct isci_tmf *)request->task)); */ tmf_complete = tmf->complete; - scic_controller_complete_io(&ihost->sci, &idev->sci, &ireq->sci); + scic_controller_complete_io(&ihost->sci, ireq->sci.target_device, &ireq->sci); /* set the 'terminated' flag handle to make sure it cannot be terminated * or completed again. */ @@ -1583,11 +1528,10 @@ static void isci_wait_for_smp_phy_reset(struct isci_remote_device *idev, int phy dev_dbg(&ihost->pdev->dev, "%s: done\n", __func__); } -static int isci_reset_device(struct domain_device *dev, int hard_reset) +static int isci_reset_device(struct isci_host *ihost, + struct isci_remote_device *idev, int hard_reset) { - struct isci_remote_device *idev = dev->lldd_dev; - struct sas_phy *phy = sas_find_local_phy(dev); - struct isci_host *ihost = dev_to_ihost(dev); + struct sas_phy *phy = sas_find_local_phy(idev->domain_dev); struct isci_port *iport = idev->isci_port; enum sci_status status; unsigned long flags; @@ -1595,14 +1539,6 @@ static int isci_reset_device(struct domain_device *dev, int hard_reset) dev_dbg(&ihost->pdev->dev, "%s: idev %p\n", __func__, idev); - if (!idev) { - dev_warn(&ihost->pdev->dev, - "%s: idev is GONE!\n", - __func__); - - return TMF_RESP_FUNC_COMPLETE; /* Nothing to reset. */ - } - spin_lock_irqsave(&ihost->scic_lock, flags); status = scic_remote_device_reset(&idev->sci); if (status != SCI_SUCCESS) { @@ -1662,35 +1598,50 @@ static int isci_reset_device(struct domain_device *dev, int hard_reset) int isci_task_I_T_nexus_reset(struct domain_device *dev) { struct isci_host *ihost = dev_to_ihost(dev); - int ret = TMF_RESP_FUNC_FAILED, hard_reset = 1; struct isci_remote_device *idev; + int ret, hard_reset = 1; unsigned long flags; - /* XXX mvsas is not protecting against ->lldd_dev_gone(), are we - * being too paranoid, or is mvsas busted?! - */ spin_lock_irqsave(&ihost->scic_lock, flags); - idev = dev->lldd_dev; - if (!idev || !test_bit(IDEV_EH, &idev->flags)) - ret = TMF_RESP_FUNC_COMPLETE; + idev = isci_lookup_device(dev); spin_unlock_irqrestore(&ihost->scic_lock, flags); - if (ret == TMF_RESP_FUNC_COMPLETE) - return ret; + if (!idev || !test_bit(IDEV_EH, &idev->flags)) { + ret = TMF_RESP_FUNC_COMPLETE; + goto out; + } if (dev->dev_type == SATA_DEV || (dev->tproto & SAS_PROTOCOL_STP)) hard_reset = 0; - return isci_reset_device(dev, hard_reset); + ret = isci_reset_device(ihost, idev, hard_reset); + out: + isci_put_device(idev); + return ret; } int isci_bus_reset_handler(struct scsi_cmnd *cmd) { struct domain_device *dev = sdev_to_domain_dev(cmd->device); - int hard_reset = 1; + struct isci_host *ihost = dev_to_ihost(dev); + struct isci_remote_device *idev; + int ret, hard_reset = 1; + unsigned long flags; if (dev->dev_type == SATA_DEV || (dev->tproto & SAS_PROTOCOL_STP)) hard_reset = 0; - return isci_reset_device(dev, hard_reset); + spin_lock_irqsave(&ihost->scic_lock, flags); + idev = isci_lookup_device(dev); + spin_unlock_irqrestore(&ihost->scic_lock, flags); + + if (!idev) { + ret = TMF_RESP_FUNC_COMPLETE; + goto out; + } + + ret = isci_reset_device(ihost, idev, hard_reset); + out: + isci_put_device(idev); + return ret; } diff --git a/drivers/scsi/isci/task.h b/drivers/scsi/isci/task.h index d574a18956d..42019de2380 100644 --- a/drivers/scsi/isci/task.h +++ b/drivers/scsi/isci/task.h @@ -213,18 +213,15 @@ int isci_bus_reset_handler(struct scsi_cmnd *cmd); void isci_task_build_tmf( struct isci_tmf *tmf, - struct isci_remote_device *isci_device, enum isci_tmf_function_codes code, void (*tmf_sent_cb)(enum isci_tmf_cb_state, struct isci_tmf *, void *), void *cb_data); - -int isci_task_execute_tmf( - struct isci_host *isci_host, - struct isci_tmf *tmf, - unsigned long timeout_ms); +int isci_task_execute_tmf(struct isci_host *isci_host, + struct isci_remote_device *idev, + struct isci_tmf *tmf, unsigned long timeout_ms); /** * enum isci_completion_selection - This enum defines the possible actions to -- 2.20.1