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Diffstat (limited to 'drivers/scsi/isci/timers.c')
| -rw-r--r-- | drivers/scsi/isci/timers.c | 319 |
1 files changed, 319 insertions, 0 deletions
diff --git a/drivers/scsi/isci/timers.c b/drivers/scsi/isci/timers.c new file mode 100644 index 000000000000..ca723089ee88 --- /dev/null +++ b/drivers/scsi/isci/timers.c @@ -0,0 +1,319 @@ +/* + * This file is provided under a dual BSD/GPLv2 license. When using or + * redistributing this file, you may do so under either license. + * + * GPL LICENSE SUMMARY + * + * Copyright(c) 2008 - 2011 Intel Corporation. All rights reserved. + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of version 2 of the GNU General Public License as + * published by the Free Software Foundation. + * + * This program is distributed in the hope that it will be useful, but + * WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + * General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, write to the Free Software + * Foundation, Inc., 51 Franklin St - Fifth Floor, Boston, MA 02110-1301 USA. + * The full GNU General Public License is included in this distribution + * in the file called LICENSE.GPL. + * + * BSD LICENSE + * + * Copyright(c) 2008 - 2011 Intel Corporation. All rights reserved. + * All rights reserved. + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions + * are met: + * + * * Redistributions of source code must retain the above copyright + * notice, this list of conditions and the following disclaimer. + * * Redistributions in binary form must reproduce the above copyright + * notice, this list of conditions and the following disclaimer in + * the documentation and/or other materials provided with the + * distribution. + * * Neither the name of Intel Corporation nor the names of its + * contributors may be used to endorse or promote products derived + * from this software without specific prior written permission. + * + * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS + * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT + * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR + * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT + * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, + * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT + * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, + * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY + * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT + * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE + * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. + */ + +#include "isci.h" +#include "timers.h" + + +/** + * isci_timer_list_construct() - This method contrucst the SCI Timer List + * object used by the SCI Module class. The construction process involves + * creating isci_timer objects and adding them to the SCI Timer List + * object's list member. The number of isci_timer objects is determined by + * the timer_list_size parameter. + * @isci_timer_list: This parameter points to the SCI Timer List object being + * constructed. The calling routine is responsible for allocating the memory + * for isci_timer_list and initializing the timer list_head member of + * isci_timer_list. + * @timer_list_size: This parameter specifies the number of isci_timer objects + * contained by the SCI Timer List. which this timer is to be associated. + * + * This method returns an error code indicating sucess or failure. The user + * should check for possible memory allocation error return otherwise, a zero + * indicates success. + */ +int isci_timer_list_construct( + struct isci_timer_list *isci_timer_list, + int timer_list_size) +{ + struct isci_timer *isci_timer; + int i; + int err = 0; + + + for (i = 0; i < timer_list_size; i++) { + + isci_timer = kzalloc(sizeof(*isci_timer), GFP_KERNEL); + + if (!isci_timer) { + + err = -ENOMEM; + break; + } + isci_timer->used = 0; + isci_timer->stopped = 1; + isci_timer->parent = isci_timer_list; + list_add(&isci_timer->node, &isci_timer_list->timers); + } + + return 0; + +} + + +/** + * isci_timer_list_destroy() - This method destroys the SCI Timer List object + * used by the SCI Module class. The destruction process involves freeing + * memory allocated for isci_timer objects on the SCI Timer List object's + * timers list_head member. If any isci_timer objects are mark as "in use", + * they are not freed and the function returns an error code of -EBUSY. + * @isci_timer_list: This parameter points to the SCI Timer List object being + * destroyed. + * + * This method returns an error code indicating sucess or failure. The user + * should check for possible -EBUSY error return, in the event of one or more + * isci_timers still "in use", otherwise, a zero indicates success. + */ +int isci_timer_list_destroy( + struct isci_timer_list *isci_timer_list) +{ + struct isci_timer *timer, *tmp; + + list_for_each_entry_safe(timer, tmp, &isci_timer_list->timers, node) { + isci_timer_free(isci_timer_list, timer); + list_del(&timer->node); + kfree(timer); + } + return 0; +} + + + +static void isci_timer_restart(struct isci_timer *isci_timer) +{ + struct timer_list *timer = + &isci_timer->timer; + unsigned long timeout; + + dev_dbg(&isci_timer->isci_host->pdev->dev, + "%s: isci_timer = %p\n", __func__, isci_timer); + + isci_timer->restart = 0; + isci_timer->stopped = 0; + timeout = isci_timer->timeout_value; + timeout = (timeout * HZ) / 1000; + timeout = timeout ? timeout : 1; + mod_timer(timer, jiffies + timeout); +} + +/** + * This method pulls an isci_timer object off of the list for the SCI Timer + * List object specified, marks the isci_timer as "in use" and initializes + * it with user callback function and cookie data. The timer is not start at + * this time, just reserved for the user. + * @isci_timer_list: This parameter points to the SCI Timer List from which the + * timer is reserved. + * @cookie: This parameter specifies a piece of information that the user must + * retain. This cookie is to be supplied by the user anytime a timeout + * occurs for the created timer. + * @timer_callback: This parameter specifies the callback method to be invoked + * whenever the timer expires. + * + * This method returns a pointer to an isci_timer object reserved from the SCI + * Timer List. The pointer will be utilized for all further interactions + * relating to this timer. + */ + +static void timer_function(unsigned long data) +{ + + struct isci_timer *timer = (struct isci_timer *)data; + struct isci_host *isci_host = timer->isci_host; + unsigned long flags; + + dev_dbg(&isci_host->pdev->dev, + "%s: isci_timer = %p\n", __func__, timer); + + if (isci_stopped == isci_host_get_state(isci_host)) { + timer->stopped = 1; + return; + } + + spin_lock_irqsave(&isci_host->scic_lock, flags); + + if (!timer->stopped) { + timer->stopped = 1; + timer->timer_callback(timer->cookie); + + if (timer->restart) + isci_timer_restart(timer); + } + + spin_unlock_irqrestore(&isci_host->scic_lock, flags); +} + + +struct isci_timer *isci_timer_create( + struct isci_timer_list *isci_timer_list, + struct isci_host *isci_host, + void *cookie, + void (*timer_callback)(void *)) +{ + + struct timer_list *timer; + struct isci_timer *isci_timer; + struct list_head *timer_list = + &isci_timer_list->timers; + unsigned long flags; + + spin_lock_irqsave(&isci_host->scic_lock, flags); + + if (list_empty(timer_list)) { + spin_unlock_irqrestore(&isci_host->scic_lock, flags); + return NULL; + } + + isci_timer = list_entry(timer_list->next, struct isci_timer, node); + + if (isci_timer->used) { + spin_unlock_irqrestore(&isci_host->scic_lock, flags); + return NULL; + } + isci_timer->used = 1; + isci_timer->stopped = 1; + list_move_tail(&isci_timer->node, timer_list); + + spin_unlock_irqrestore(&isci_host->scic_lock, flags); + + timer = &isci_timer->timer; + timer->data = (unsigned long)isci_timer; + timer->function = timer_function; + isci_timer->cookie = cookie; + isci_timer->timer_callback = timer_callback; + isci_timer->isci_host = isci_host; + + dev_dbg(&isci_host->pdev->dev, + "%s: isci_timer = %p\n", __func__, isci_timer); + + return isci_timer; +} + +/** + * isci_timer_free() - This method frees the isci_timer, marking it "free to + * use", then places its back at the head of the timers list for the SCI + * Timer List object specified. + * @isci_timer_list: This parameter points to the SCI Timer List from which the + * timer is reserved. + * @isci_timer: This parameter specifies the timer to be freed. + * + */ +void isci_timer_free( + struct isci_timer_list *isci_timer_list, + struct isci_timer *isci_timer) +{ + struct list_head *timer_list = &isci_timer_list->timers; + + dev_dbg(&isci_timer->isci_host->pdev->dev, + "%s: isci_timer = %p\n", __func__, isci_timer); + + if (list_empty(timer_list)) + return; + + isci_timer->used = 0; + list_move(&isci_timer->node, timer_list); + + if (!isci_timer->stopped) { + del_timer(&isci_timer->timer); + isci_timer->stopped = 1; + } +} + +/** + * isci_timer_start() - This method starts the specified isci_timer, with the + * specified timeout value. + * @isci_timer: This parameter specifies the timer to be started. + * @timeout: This parameter specifies the timeout, in milliseconds, after which + * the associated callback function will be called. + * + */ +void isci_timer_start( + struct isci_timer *isci_timer, + unsigned long timeout) +{ + struct timer_list *timer = &isci_timer->timer; + + dev_dbg(&isci_timer->isci_host->pdev->dev, + "%s: isci_timer = %p\n", __func__, isci_timer); + + isci_timer->timeout_value = timeout; + init_timer(timer); + timeout = (timeout * HZ) / 1000; + timeout = timeout ? timeout : 1; + + timer->expires = jiffies + timeout; + timer->data = (unsigned long)isci_timer; + timer->function = timer_function; + isci_timer->stopped = 0; + isci_timer->restart = 0; + add_timer(timer); +} + +/** + * isci_timer_stop() - This method stops the supplied isci_timer. + * @isci_timer: This parameter specifies the isci_timer to be stopped. + * + */ +void isci_timer_stop(struct isci_timer *isci_timer) +{ + dev_dbg(&isci_timer->isci_host->pdev->dev, + "%s: isci_timer = %p\n", __func__, isci_timer); + + if (isci_timer->stopped) + return; + + isci_timer->stopped = 1; + + del_timer(&isci_timer->timer); +} |