From 312e0c2455c18716cf640d4336dcb1e9e5053818 Mon Sep 17 00:00:00 2001 From: Dan Williams Date: Tue, 28 Jun 2011 13:47:09 -0700 Subject: isci: unify can_queue tracking on the tci_pool, uplevel tag assignment The tci_pool tracks our outstanding command slots which are also the 'index' portion of our tags. Grabbing the tag early in ->lldd_execute_task let's us drop the isci_host_can_queue() and ->was_tag_assigned_by_user infrastructure. ->was_tag_assigned_by_user required the task context to be duplicated in request-local buffer. With the tci established early we can build the task_context directly into its final location and skip a memcpy. With the task context buffer at a known address at request construction we have the opportunity/obligation to also fix sgl handling. This rework feels like it belongs in another patch but the sgl handling and task_context are too intertwined. 1/ fix the 'ab' pair embedded in the task context to point to the 'cd' pair in the task context (previously we were prematurely linking to the staging buffer). 2/ fix the broken iteration of pio sgls that assumes all sgls are relative to the request, and does a dangerous looking reverse lookup of physical address to virtual address. Signed-off-by: Dan Williams --- drivers/scsi/isci/host.c | 265 ++++++++++++----------------------------------- 1 file changed, 64 insertions(+), 201 deletions(-) (limited to 'drivers/scsi/isci/host.c') diff --git a/drivers/scsi/isci/host.c b/drivers/scsi/isci/host.c index b08455f0d350..c99fab53dd0c 100644 --- a/drivers/scsi/isci/host.c +++ b/drivers/scsi/isci/host.c @@ -1018,33 +1018,11 @@ done: spin_unlock_irqrestore(&ihost->scic_lock, flags); } -static void isci_tci_free(struct isci_host *ihost, u16 tci) -{ - u16 tail = ihost->tci_tail & (SCI_MAX_IO_REQUESTS-1); - - ihost->tci_pool[tail] = tci; - ihost->tci_tail = tail + 1; -} - -static u16 isci_tci_alloc(struct isci_host *ihost) -{ - u16 head = ihost->tci_head & (SCI_MAX_IO_REQUESTS-1); - u16 tci = ihost->tci_pool[head]; - - ihost->tci_head = head + 1; - return tci; -} - static u16 isci_tci_active(struct isci_host *ihost) { return CIRC_CNT(ihost->tci_head, ihost->tci_tail, SCI_MAX_IO_REQUESTS); } -static u16 isci_tci_space(struct isci_host *ihost) -{ - return CIRC_SPACE(ihost->tci_head, ihost->tci_tail, SCI_MAX_IO_REQUESTS); -} - static enum sci_status scic_controller_start(struct scic_sds_controller *scic, u32 timeout) { @@ -1205,6 +1183,11 @@ static void isci_host_completion_routine(unsigned long data) task->task_done(task); } } + + spin_lock_irq(&isci_host->scic_lock); + isci_free_tag(isci_host, request->sci.io_tag); + spin_unlock_irq(&isci_host->scic_lock); + /* Free the request object. */ isci_request_free(isci_host, request); } @@ -1242,6 +1225,7 @@ static void isci_host_completion_routine(unsigned long data) * of pending requests. */ list_del_init(&request->dev_node); + isci_free_tag(isci_host, request->sci.io_tag); spin_unlock_irq(&isci_host->scic_lock); /* Free the request object. */ @@ -2375,6 +2359,7 @@ static int scic_controller_mem_init(struct scic_sds_controller *scic) if (!scic->task_context_table) return -ENOMEM; + scic->task_context_dma = dma; writel(lower_32_bits(dma), &scic->smu_registers->host_task_table_lower); writel(upper_32_bits(dma), &scic->smu_registers->host_task_table_upper); @@ -2409,11 +2394,9 @@ int isci_host_init(struct isci_host *isci_host) spin_lock_init(&isci_host->state_lock); spin_lock_init(&isci_host->scic_lock); - spin_lock_init(&isci_host->queue_lock); init_waitqueue_head(&isci_host->eventq); isci_host_change_state(isci_host, isci_starting); - isci_host->can_queue = ISCI_CAN_QUEUE_VAL; status = scic_controller_construct(&isci_host->sci, scu_base(isci_host), smu_base(isci_host)); @@ -2611,51 +2594,6 @@ void scic_sds_controller_post_request( writel(request, &scic->smu_registers->post_context_port); } -/** - * This method will copy the soft copy of the task context into the physical - * memory accessible by the controller. - * @scic: This parameter specifies the controller for which to copy - * the task context. - * @sci_req: This parameter specifies the request for which the task - * context is being copied. - * - * After this call is made the SCIC_SDS_IO_REQUEST object will always point to - * the physical memory version of the task context. Thus, all subsequent - * updates to the task context are performed in the TC table (i.e. DMAable - * memory). none - */ -void scic_sds_controller_copy_task_context( - struct scic_sds_controller *scic, - struct scic_sds_request *sci_req) -{ - struct scu_task_context *task_context_buffer; - - task_context_buffer = scic_sds_controller_get_task_context_buffer( - scic, sci_req->io_tag); - - memcpy(task_context_buffer, - sci_req->task_context_buffer, - offsetof(struct scu_task_context, sgl_snapshot_ac)); - - /* - * Now that the soft copy of the TC has been copied into the TC - * table accessible by the silicon. Thus, any further changes to - * the TC (e.g. TC termination) occur in the appropriate location. */ - sci_req->task_context_buffer = task_context_buffer; -} - -struct scu_task_context *scic_sds_controller_get_task_context_buffer(struct scic_sds_controller *scic, - u16 io_tag) -{ - u16 tci = ISCI_TAG_TCI(io_tag); - - if (tci < scic->task_context_entries) { - return &scic->task_context_table[tci]; - } - - return NULL; -} - struct scic_sds_request *scic_request_by_tag(struct scic_sds_controller *scic, u16 io_tag) { u16 task_index; @@ -2801,6 +2739,60 @@ void scic_sds_controller_release_frame( &scic->scu_registers->sdma.unsolicited_frame_get_pointer); } +void isci_tci_free(struct isci_host *ihost, u16 tci) +{ + u16 tail = ihost->tci_tail & (SCI_MAX_IO_REQUESTS-1); + + ihost->tci_pool[tail] = tci; + ihost->tci_tail = tail + 1; +} + +static u16 isci_tci_alloc(struct isci_host *ihost) +{ + u16 head = ihost->tci_head & (SCI_MAX_IO_REQUESTS-1); + u16 tci = ihost->tci_pool[head]; + + ihost->tci_head = head + 1; + return tci; +} + +static u16 isci_tci_space(struct isci_host *ihost) +{ + return CIRC_SPACE(ihost->tci_head, ihost->tci_tail, SCI_MAX_IO_REQUESTS); +} + +u16 isci_alloc_tag(struct isci_host *ihost) +{ + if (isci_tci_space(ihost)) { + u16 tci = isci_tci_alloc(ihost); + u8 seq = ihost->sci.io_request_sequence[tci]; + + return ISCI_TAG(seq, tci); + } + + return SCI_CONTROLLER_INVALID_IO_TAG; +} + +enum sci_status isci_free_tag(struct isci_host *ihost, u16 io_tag) +{ + struct scic_sds_controller *scic = &ihost->sci; + u16 tci = ISCI_TAG_TCI(io_tag); + u16 seq = ISCI_TAG_SEQ(io_tag); + + /* prevent tail from passing head */ + if (isci_tci_active(ihost) == 0) + return SCI_FAILURE_INVALID_IO_TAG; + + if (seq == scic->io_request_sequence[tci]) { + scic->io_request_sequence[tci] = (seq+1) & (SCI_MAX_SEQ-1); + + isci_tci_free(ihost, tci); + + return SCI_SUCCESS; + } + return SCI_FAILURE_INVALID_IO_TAG; +} + /** * scic_controller_start_io() - This method is called by the SCI user to * send/start an IO request. If the method invocation is successful, then @@ -2811,27 +2803,11 @@ void scic_sds_controller_release_frame( * IO request. * @io_request: the handle to the io request object to start. * @io_tag: This parameter specifies a previously allocated IO tag that the - * user desires to be utilized for this request. This parameter is optional. - * The user is allowed to supply SCI_CONTROLLER_INVALID_IO_TAG as the value - * for this parameter. - * - * - IO tags are a protected resource. It is incumbent upon the SCI Core user - * to ensure that each of the methods that may allocate or free available IO - * tags are handled in a mutually exclusive manner. This method is one of said - * methods requiring proper critical code section protection (e.g. semaphore, - * spin-lock, etc.). - For SATA, the user is required to manage NCQ tags. As a - * result, it is expected the user will have set the NCQ tag field in the host - * to device register FIS prior to calling this method. There is also a - * requirement for the user to call scic_stp_io_set_ncq_tag() prior to invoking - * the scic_controller_start_io() method. scic_controller_allocate_tag() for - * more information on allocating a tag. Indicate if the controller - * successfully started the IO request. SCI_SUCCESS if the IO request was - * successfully started. Determine the failure situations and return values. + * user desires to be utilized for this request. */ enum sci_status scic_controller_start_io(struct scic_sds_controller *scic, struct scic_sds_remote_device *rdev, - struct scic_sds_request *req, - u16 io_tag) + struct scic_sds_request *req) { enum sci_status status; @@ -2902,17 +2878,6 @@ enum sci_status scic_controller_terminate_request( * @remote_device: The handle to the remote device object for which to complete * the IO request. * @io_request: the handle to the io request object to complete. - * - * - IO tags are a protected resource. It is incumbent upon the SCI Core user - * to ensure that each of the methods that may allocate or free available IO - * tags are handled in a mutually exclusive manner. This method is one of said - * methods requiring proper critical code section protection (e.g. semaphore, - * spin-lock, etc.). - If the IO tag for a request was allocated, by the SCI - * Core user, using the scic_controller_allocate_io_tag() method, then it is - * the responsibility of the caller to invoke the scic_controller_free_io_tag() - * method to free the tag (i.e. this method will not free the IO tag). Indicate - * if the controller successfully completed the IO request. SCI_SUCCESS if the - * completion process was successful. */ enum sci_status scic_controller_complete_io( struct scic_sds_controller *scic, @@ -2963,31 +2928,11 @@ enum sci_status scic_controller_continue_io(struct scic_sds_request *sci_req) * @remote_device: the handle to the remote device object for which to start * the task management request. * @task_request: the handle to the task request object to start. - * @io_tag: This parameter specifies a previously allocated IO tag that the - * user desires to be utilized for this request. Note this not the io_tag - * of the request being managed. It is to be utilized for the task request - * itself. This parameter is optional. The user is allowed to supply - * SCI_CONTROLLER_INVALID_IO_TAG as the value for this parameter. - * - * - IO tags are a protected resource. It is incumbent upon the SCI Core user - * to ensure that each of the methods that may allocate or free available IO - * tags are handled in a mutually exclusive manner. This method is one of said - * methods requiring proper critical code section protection (e.g. semaphore, - * spin-lock, etc.). - The user must synchronize this task with completion - * queue processing. If they are not synchronized then it is possible for the - * io requests that are being managed by the task request can complete before - * starting the task request. scic_controller_allocate_tag() for more - * information on allocating a tag. Indicate if the controller successfully - * started the IO request. SCI_TASK_SUCCESS if the task request was - * successfully started. SCI_TASK_FAILURE_REQUIRES_SCSI_ABORT This value is - * returned if there is/are task(s) outstanding that require termination or - * completion before this request can succeed. */ enum sci_task_status scic_controller_start_task( struct scic_sds_controller *scic, struct scic_sds_remote_device *rdev, - struct scic_sds_request *req, - u16 task_tag) + struct scic_sds_request *req) { enum sci_status status; @@ -3022,85 +2967,3 @@ enum sci_task_status scic_controller_start_task( return status; } - -/** - * scic_controller_allocate_io_tag() - This method will allocate a tag from the - * pool of free IO tags. Direct allocation of IO tags by the SCI Core user - * is optional. The scic_controller_start_io() method will allocate an IO - * tag if this method is not utilized and the tag is not supplied to the IO - * construct routine. Direct allocation of IO tags may provide additional - * performance improvements in environments capable of supporting this usage - * model. Additionally, direct allocation of IO tags also provides - * additional flexibility to the SCI Core user. Specifically, the user may - * retain IO tags across the lives of multiple IO requests. - * @controller: the handle to the controller object for which to allocate the - * tag. - * - * IO tags are a protected resource. It is incumbent upon the SCI Core user to - * ensure that each of the methods that may allocate or free available IO tags - * are handled in a mutually exclusive manner. This method is one of said - * methods requiring proper critical code section protection (e.g. semaphore, - * spin-lock, etc.). An unsigned integer representing an available IO tag. - * SCI_CONTROLLER_INVALID_IO_TAG This value is returned if there are no - * currently available tags to be allocated. All return other values indicate a - * legitimate tag. - */ -u16 scic_controller_allocate_io_tag(struct scic_sds_controller *scic) -{ - struct isci_host *ihost = scic_to_ihost(scic); - - if (isci_tci_space(ihost)) { - u16 tci = isci_tci_alloc(ihost); - u8 seq = scic->io_request_sequence[tci]; - - return ISCI_TAG(seq, tci); - } - - return SCI_CONTROLLER_INVALID_IO_TAG; -} - -/** - * scic_controller_free_io_tag() - This method will free an IO tag to the pool - * of free IO tags. This method provides the SCI Core user more flexibility - * with regards to IO tags. The user may desire to keep an IO tag after an - * IO request has completed, because they plan on re-using the tag for a - * subsequent IO request. This method is only legal if the tag was - * allocated via scic_controller_allocate_io_tag(). - * @controller: This parameter specifies the handle to the controller object - * for which to free/return the tag. - * @io_tag: This parameter represents the tag to be freed to the pool of - * available tags. - * - * - IO tags are a protected resource. It is incumbent upon the SCI Core user - * to ensure that each of the methods that may allocate or free available IO - * tags are handled in a mutually exclusive manner. This method is one of said - * methods requiring proper critical code section protection (e.g. semaphore, - * spin-lock, etc.). - If the IO tag for a request was allocated, by the SCI - * Core user, using the scic_controller_allocate_io_tag() method, then it is - * the responsibility of the caller to invoke this method to free the tag. This - * method returns an indication of whether the tag was successfully put back - * (freed) to the pool of available tags. SCI_SUCCESS This return value - * indicates the tag was successfully placed into the pool of available IO - * tags. SCI_FAILURE_INVALID_IO_TAG This value is returned if the supplied tag - * is not a valid IO tag value. - */ -enum sci_status scic_controller_free_io_tag(struct scic_sds_controller *scic, - u16 io_tag) -{ - struct isci_host *ihost = scic_to_ihost(scic); - u16 tci = ISCI_TAG_TCI(io_tag); - u16 seq = ISCI_TAG_SEQ(io_tag); - - /* prevent tail from passing head */ - if (isci_tci_active(ihost) == 0) - return SCI_FAILURE_INVALID_IO_TAG; - - if (seq == scic->io_request_sequence[tci]) { - scic->io_request_sequence[tci] = (seq+1) & (SCI_MAX_SEQ-1); - - isci_tci_free(ihost, ISCI_TAG_TCI(io_tag)); - - return SCI_SUCCESS; - } - return SCI_FAILURE_INVALID_IO_TAG; -} -- cgit v1.2.3