From bb5cb290f095f17f88c912e3da35adf5b2d9500b Mon Sep 17 00:00:00 2001 From: Albert Lee Date: Sat, 25 Mar 2006 17:48:02 +0800 Subject: [PATCH] [PATCH] libata-dev: Let ata_hsm_move() work with both irq-pio and polling pio Let ata_hsm_move() work with both irq-pio and polling pio codepath. Changes: - add a new parameter "in_wq" for polling pio - add return value "poll_next" to tell polling pio task whether the HSM is finished - merge code from ata_pio_first_block() to the HSM_ST_FIRST state. - call ata_poll_qc_complete() if called from the workqueue Signed-off-by: Albert Lee Signed-off-by: Jeff Garzik --- drivers/scsi/libata-core.c | 87 ++++++++++++++++++++++++++++++++++++++++++---- 1 file changed, 81 insertions(+), 6 deletions(-) diff --git a/drivers/scsi/libata-core.c b/drivers/scsi/libata-core.c index 094c790..33b39d3 100644 --- a/drivers/scsi/libata-core.c +++ b/drivers/scsi/libata-core.c @@ -3805,11 +3805,36 @@ static void ata_pio_error(struct ata_port *ap) ata_poll_qc_complete(qc); } -static void ata_hsm_move(struct ata_port *ap, struct ata_queued_cmd *qc, - u8 status) +/** + * ata_hsm_move - move the HSM to the next state. + * @ap: the target ata_port + * @qc: qc on going + * @status: current device status + * @in_wq: 1 if called from workqueue, 0 otherwise + * + * RETURNS: + * 1 when poll next status needed, 0 otherwise. + */ + +static int ata_hsm_move(struct ata_port *ap, struct ata_queued_cmd *qc, + u8 status, int in_wq) { + unsigned long flags = 0; + int poll_next; + WARN_ON((qc->flags & ATA_QCFLAG_ACTIVE) == 0); + /* Make sure ata_qc_issue_prot() does not throw things + * like DMA polling into the workqueue. Notice that + * in_wq is not equivalent to (qc->tf.flags & ATA_TFLAG_POLLING). + */ + WARN_ON(in_wq != ((qc->tf.flags & ATA_TFLAG_POLLING) || + (ap->hsm_task_state == HSM_ST_FIRST && + ((qc->tf.protocol == ATA_PROT_PIO && + (qc->tf.flags & ATA_TFLAG_WRITE)) || + (is_atapi_taskfile(&qc->tf) && + !(qc->dev->flags & ATA_DFLAG_CDB_INTR)))))); + /* check error */ if (unlikely(status & (ATA_ERR | ATA_DF))) { qc->err_mask |= AC_ERR_DEV; @@ -3819,6 +3844,14 @@ static void ata_hsm_move(struct ata_port *ap, struct ata_queued_cmd *qc, fsm_start: switch (ap->hsm_task_state) { case HSM_ST_FIRST: + /* Send first data block or PACKET CDB */ + + /* If polling, we will stay in the work queue after + * sending the data. Otherwise, interrupt handler + * takes over after sending the data. + */ + poll_next = (qc->tf.flags & ATA_TFLAG_POLLING); + /* check device status */ if (unlikely((status & (ATA_BUSY | ATA_DRQ)) != ATA_DRQ)) { /* Wrong status. Let EH handle this */ @@ -3827,8 +3860,36 @@ fsm_start: goto fsm_start; } - atapi_send_cdb(ap, qc); + /* Send the CDB (atapi) or the first data block (ata pio out). + * During the state transition, interrupt handler shouldn't + * be invoked before the data transfer is complete and + * hsm_task_state is changed. Hence, the following locking. + */ + if (in_wq) + spin_lock_irqsave(&ap->host_set->lock, flags); + + if (qc->tf.protocol == ATA_PROT_PIO) { + /* PIO data out protocol. + * send first data block. + */ + /* ata_pio_sectors() might change the state + * to HSM_ST_LAST. so, the state is changed here + * before ata_pio_sectors(). + */ + ap->hsm_task_state = HSM_ST; + ata_pio_sectors(qc); + ata_altstatus(ap); /* flush */ + } else + /* send CDB */ + atapi_send_cdb(ap, qc); + + if (in_wq) + spin_unlock_irqrestore(&ap->host_set->lock, flags); + + /* if polling, ata_pio_task() handles the rest. + * otherwise, interrupt handler takes over from here. + */ break; case HSM_ST: @@ -3868,6 +3929,7 @@ fsm_start: } ata_altstatus(ap); /* flush */ + poll_next = 1; break; case HSM_ST_LAST: @@ -3886,7 +3948,12 @@ fsm_start: ap->hsm_task_state = HSM_ST_IDLE; /* complete taskfile transaction */ - ata_qc_complete(qc); + if (in_wq) + ata_poll_qc_complete(qc); + else + ata_qc_complete(qc); + + poll_next = 0; break; case HSM_ST_ERR: @@ -3900,12 +3967,20 @@ fsm_start: WARN_ON(qc->err_mask == 0); ap->hsm_task_state = HSM_ST_IDLE; - ata_qc_complete(qc); + + if (in_wq) + ata_poll_qc_complete(qc); + else + ata_qc_complete(qc); + + poll_next = 0; break; default: + poll_next = 0; BUG(); } + return poll_next; } static void ata_pio_task(void *_data) @@ -4423,7 +4498,7 @@ inline unsigned int ata_host_intr (struct ata_port *ap, /* ack bmdma irq events */ ap->ops->irq_clear(ap); - ata_hsm_move(ap, qc, status); + ata_hsm_move(ap, qc, status, 0); return 1; /* irq handled */ idle_irq: -- 2.7.4