diff options
| -rw-r--r-- | drivers/scsi/libata-core.c | 77 | ||||
| -rw-r--r-- | drivers/scsi/libata-scsi.c | 2 | ||||
| -rw-r--r-- | drivers/scsi/libata.h | 1 | ||||
| -rw-r--r-- | include/linux/libata.h | 4 |
4 files changed, 84 insertions, 0 deletions
diff --git a/drivers/scsi/libata-core.c b/drivers/scsi/libata-core.c index 5dbcf0cf4a10..d59d462130c1 100644 --- a/drivers/scsi/libata-core.c +++ b/drivers/scsi/libata-core.c @@ -721,6 +721,81 @@ static unsigned int ata_pio_modes(const struct ata_device *adev) timing API will get this right anyway */ } +/** + * ata_port_queue_task - Queue port_task + * @ap: The ata_port to queue port_task for + * + * Schedule @fn(@data) for execution after @delay jiffies using + * port_task. There is one port_task per port and it's the + * user(low level driver)'s responsibility to make sure that only + * one task is active at any given time. + * + * libata core layer takes care of synchronization between + * port_task and EH. ata_port_queue_task() may be ignored for EH + * synchronization. + * + * LOCKING: + * Inherited from caller. + */ +void ata_port_queue_task(struct ata_port *ap, void (*fn)(void *), void *data, + unsigned long delay) +{ + int rc; + + if (ap->flags & ATA_FLAG_FLUSH_PIO_TASK) + return; + + PREPARE_WORK(&ap->port_task, fn, data); + + if (!delay) + rc = queue_work(ata_wq, &ap->port_task); + else + rc = queue_delayed_work(ata_wq, &ap->port_task, delay); + + /* rc == 0 means that another user is using port task */ + WARN_ON(rc == 0); +} + +/** + * ata_port_flush_task - Flush port_task + * @ap: The ata_port to flush port_task for + * + * After this function completes, port_task is guranteed not to + * be running or scheduled. + * + * LOCKING: + * Kernel thread context (may sleep) + */ +void ata_port_flush_task(struct ata_port *ap) +{ + unsigned long flags; + + DPRINTK("ENTER\n"); + + spin_lock_irqsave(&ap->host_set->lock, flags); + ap->flags |= ATA_FLAG_FLUSH_PIO_TASK; + spin_unlock_irqrestore(&ap->host_set->lock, flags); + + DPRINTK("flush #1\n"); + flush_workqueue(ata_wq); + + /* + * At this point, if a task is running, it's guaranteed to see + * the FLUSH flag; thus, it will never queue pio tasks again. + * Cancel and flush. + */ + if (!cancel_delayed_work(&ap->port_task)) { + DPRINTK("flush #2\n"); + flush_workqueue(ata_wq); + } + + spin_lock_irqsave(&ap->host_set->lock, flags); + ap->flags &= ~ATA_FLAG_FLUSH_PIO_TASK; + spin_unlock_irqrestore(&ap->host_set->lock, flags); + + DPRINTK("EXIT\n"); +} + static inline void ata_queue_packet_task(struct ata_port *ap) { @@ -4617,6 +4692,7 @@ static void ata_host_init(struct ata_port *ap, struct Scsi_Host *host, ap->active_tag = ATA_TAG_POISON; ap->last_ctl = 0xFF; + INIT_WORK(&ap->port_task, NULL, NULL); INIT_WORK(&ap->packet_task, atapi_packet_task, ap); INIT_WORK(&ap->pio_task, ata_pio_task, ap); INIT_LIST_HEAD(&ap->eh_done_q); @@ -5088,6 +5164,7 @@ EXPORT_SYMBOL_GPL(ata_dev_revalidate); EXPORT_SYMBOL_GPL(ata_port_disable); EXPORT_SYMBOL_GPL(ata_ratelimit); EXPORT_SYMBOL_GPL(ata_busy_sleep); +EXPORT_SYMBOL_GPL(ata_port_queue_task); EXPORT_SYMBOL_GPL(ata_scsi_ioctl); EXPORT_SYMBOL_GPL(ata_scsi_queuecmd); EXPORT_SYMBOL_GPL(ata_scsi_timed_out); diff --git a/drivers/scsi/libata-scsi.c b/drivers/scsi/libata-scsi.c index d0bd94abb413..ccedb4536977 100644 --- a/drivers/scsi/libata-scsi.c +++ b/drivers/scsi/libata-scsi.c @@ -785,6 +785,8 @@ int ata_scsi_error(struct Scsi_Host *host) WARN_ON(ata_qc_from_tag(ap, ap->active_tag) == NULL); spin_unlock_irqrestore(&ap->host_set->lock, flags); + ata_port_flush_task(ap); + ap->ops->eng_timeout(ap); WARN_ON(host->host_failed || !list_empty(&host->eh_cmd_q)); diff --git a/drivers/scsi/libata.h b/drivers/scsi/libata.h index d822eba05f3c..f4c48c91b63d 100644 --- a/drivers/scsi/libata.h +++ b/drivers/scsi/libata.h @@ -45,6 +45,7 @@ extern int libata_fua; extern struct ata_queued_cmd *ata_qc_new_init(struct ata_port *ap, struct ata_device *dev); extern int ata_rwcmd_protocol(struct ata_queued_cmd *qc); +extern void ata_port_flush_task(struct ata_port *ap); extern void ata_qc_free(struct ata_queued_cmd *qc); extern unsigned int ata_qc_issue(struct ata_queued_cmd *qc); extern int ata_check_atapi_dma(struct ata_queued_cmd *qc); diff --git a/include/linux/libata.h b/include/linux/libata.h index 66dce58f1941..3ad2570f663b 100644 --- a/include/linux/libata.h +++ b/include/linux/libata.h @@ -388,6 +388,8 @@ struct ata_port { struct ata_host_stats stats; struct ata_host_set *host_set; + struct work_struct port_task; + struct work_struct packet_task; struct work_struct pio_task; @@ -515,6 +517,8 @@ extern int ata_ratelimit(void); extern unsigned int ata_busy_sleep(struct ata_port *ap, unsigned long timeout_pat, unsigned long timeout); +extern void ata_port_queue_task(struct ata_port *ap, void (*fn)(void *), + void *data, unsigned long delay); /* * Default driver ops implementations |