- return ATA_DEFER_LINK;
-}
-
-/**
- * ata_qc_prep - Prepare taskfile for submission
- * @qc: Metadata associated with taskfile to be prepared
- *
- * Prepare ATA taskfile for submission.
- *
- * LOCKING:
- * spin_lock_irqsave(host lock)
- */
-void ata_qc_prep(struct ata_queued_cmd *qc)
-{
- if (!(qc->flags & ATA_QCFLAG_DMAMAP))
- return;
-
- ata_fill_sg(qc);
-}
-
-/**
- * ata_dumb_qc_prep - Prepare taskfile for submission
- * @qc: Metadata associated with taskfile to be prepared
- *
- * Prepare ATA taskfile for submission.
- *
- * LOCKING:
- * spin_lock_irqsave(host lock)
- */
-void ata_dumb_qc_prep(struct ata_queued_cmd *qc)
-{
- if (!(qc->flags & ATA_QCFLAG_DMAMAP))
- return;
-
- ata_fill_sg_dumb(qc);
-}
-
-void ata_noop_qc_prep(struct ata_queued_cmd *qc) { }
-
-/**
- * ata_sg_init - Associate command with scatter-gather table.
- * @qc: Command to be associated
- * @sg: Scatter-gather table.
- * @n_elem: Number of elements in s/g table.
- *
- * Initialize the data-related elements of queued_cmd @qc
- * to point to a scatter-gather table @sg, containing @n_elem
- * elements.
- *
- * LOCKING:
- * spin_lock_irqsave(host lock)
- */
-void ata_sg_init(struct ata_queued_cmd *qc, struct scatterlist *sg,
- unsigned int n_elem)
-{
- qc->sg = sg;
- qc->n_elem = n_elem;
- qc->cursg = qc->sg;
-}
-
-/**
- * ata_sg_setup - DMA-map the scatter-gather table associated with a command.
- * @qc: Command with scatter-gather table to be mapped.
- *
- * DMA-map the scatter-gather table associated with queued_cmd @qc.
- *
- * LOCKING:
- * spin_lock_irqsave(host lock)
- *
- * RETURNS:
- * Zero on success, negative on error.
- *
- */
-static int ata_sg_setup(struct ata_queued_cmd *qc)
-{
- struct ata_port *ap = qc->ap;
- unsigned int n_elem;
-
- VPRINTK("ENTER, ata%u\n", ap->print_id);
-
- n_elem = dma_map_sg(ap->dev, qc->sg, qc->n_elem, qc->dma_dir);
- if (n_elem < 1)
- return -1;
-
- DPRINTK("%d sg elements mapped\n", n_elem);
-
- qc->n_elem = n_elem;
- qc->flags |= ATA_QCFLAG_DMAMAP;
-
- return 0;
-}
-
-/**
- * swap_buf_le16 - swap halves of 16-bit words in place
- * @buf: Buffer to swap
- * @buf_words: Number of 16-bit words in buffer.
- *
- * Swap halves of 16-bit words if needed to convert from
- * little-endian byte order to native cpu byte order, or
- * vice-versa.
- *
- * LOCKING:
- * Inherited from caller.
- */
-void swap_buf_le16(u16 *buf, unsigned int buf_words)
-{
-#ifdef __BIG_ENDIAN
- unsigned int i;
-
- for (i = 0; i < buf_words; i++)
- buf[i] = le16_to_cpu(buf[i]);
-#endif /* __BIG_ENDIAN */
-}
-
-/**
- * ata_data_xfer - Transfer data by PIO
- * @dev: device to target
- * @buf: data buffer
- * @buflen: buffer length
- * @rw: read/write
- *
- * Transfer data from/to the device data register by PIO.
- *
- * LOCKING:
- * Inherited from caller.
- *
- * RETURNS:
- * Bytes consumed.
- */
-unsigned int ata_data_xfer(struct ata_device *dev, unsigned char *buf,
- unsigned int buflen, int rw)
-{
- struct ata_port *ap = dev->link->ap;
- void __iomem *data_addr = ap->ioaddr.data_addr;
- unsigned int words = buflen >> 1;
-
- /* Transfer multiple of 2 bytes */
- if (rw == READ)
- ioread16_rep(data_addr, buf, words);
- else
- iowrite16_rep(data_addr, buf, words);
-
- /* Transfer trailing 1 byte, if any. */
- if (unlikely(buflen & 0x01)) {
- __le16 align_buf[1] = { 0 };
- unsigned char *trailing_buf = buf + buflen - 1;
-
- if (rw == READ) {
- align_buf[0] = cpu_to_le16(ioread16(data_addr));
- memcpy(trailing_buf, align_buf, 1);
- } else {
- memcpy(align_buf, trailing_buf, 1);
- iowrite16(le16_to_cpu(align_buf[0]), data_addr);
- }
- words++;
- }
-
- return words << 1;
-}
-
-/**
- * ata_data_xfer_noirq - Transfer data by PIO
- * @dev: device to target
- * @buf: data buffer
- * @buflen: buffer length
- * @rw: read/write
- *
- * Transfer data from/to the device data register by PIO. Do the
- * transfer with interrupts disabled.
- *
- * LOCKING:
- * Inherited from caller.
- *
- * RETURNS:
- * Bytes consumed.
- */
-unsigned int ata_data_xfer_noirq(struct ata_device *dev, unsigned char *buf,
- unsigned int buflen, int rw)
-{
- unsigned long flags;
- unsigned int consumed;
-
- local_irq_save(flags);
- consumed = ata_data_xfer(dev, buf, buflen, rw);
- local_irq_restore(flags);
-
- return consumed;
-}
-
-
-/**
- * ata_pio_sector - Transfer a sector of data.
- * @qc: Command on going
- *
- * Transfer qc->sect_size bytes of data from/to the ATA device.
- *
- * LOCKING:
- * Inherited from caller.
- */
-
-static void ata_pio_sector(struct ata_queued_cmd *qc)
-{
- int do_write = (qc->tf.flags & ATA_TFLAG_WRITE);
- struct ata_port *ap = qc->ap;
- struct page *page;
- unsigned int offset;
- unsigned char *buf;
-
- if (qc->curbytes == qc->nbytes - qc->sect_size)
- ap->hsm_task_state = HSM_ST_LAST;
-
- page = sg_page(qc->cursg);
- offset = qc->cursg->offset + qc->cursg_ofs;
-
- /* get the current page and offset */
- page = nth_page(page, (offset >> PAGE_SHIFT));
- offset %= PAGE_SIZE;
-
- DPRINTK("data %s\n", qc->tf.flags & ATA_TFLAG_WRITE ? "write" : "read");
-
- if (PageHighMem(page)) {
- unsigned long flags;
-
- /* FIXME: use a bounce buffer */
- local_irq_save(flags);
- buf = kmap_atomic(page, KM_IRQ0);
-
- /* do the actual data transfer */
- ap->ops->data_xfer(qc->dev, buf + offset, qc->sect_size, do_write);
-
- kunmap_atomic(buf, KM_IRQ0);
- local_irq_restore(flags);
- } else {
- buf = page_address(page);
- ap->ops->data_xfer(qc->dev, buf + offset, qc->sect_size, do_write);
- }
-
- qc->curbytes += qc->sect_size;
- qc->cursg_ofs += qc->sect_size;
-
- if (qc->cursg_ofs == qc->cursg->length) {
- qc->cursg = sg_next(qc->cursg);
- qc->cursg_ofs = 0;
- }
-}
-
-/**
- * ata_pio_sectors - Transfer one or many sectors.
- * @qc: Command on going
- *
- * Transfer one or many sectors of data from/to the
- * ATA device for the DRQ request.
- *
- * LOCKING:
- * Inherited from caller.
- */
-
-static void ata_pio_sectors(struct ata_queued_cmd *qc)
-{
- if (is_multi_taskfile(&qc->tf)) {
- /* READ/WRITE MULTIPLE */
- unsigned int nsect;
-
- WARN_ON(qc->dev->multi_count == 0);
-
- nsect = min((qc->nbytes - qc->curbytes) / qc->sect_size,
- qc->dev->multi_count);
- while (nsect--)
- ata_pio_sector(qc);
- } else
- ata_pio_sector(qc);
-
- ata_altstatus(qc->ap); /* flush */
-}
-
-/**
- * atapi_send_cdb - Write CDB bytes to hardware
- * @ap: Port to which ATAPI device is attached.
- * @qc: Taskfile currently active
- *
- * When device has indicated its readiness to accept
- * a CDB, this function is called. Send the CDB.
- *
- * LOCKING:
- * caller.
- */
-
-static void atapi_send_cdb(struct ata_port *ap, struct ata_queued_cmd *qc)
-{
- /* send SCSI cdb */
- DPRINTK("send cdb\n");
- WARN_ON(qc->dev->cdb_len < 12);
-
- ap->ops->data_xfer(qc->dev, qc->cdb, qc->dev->cdb_len, 1);
- ata_altstatus(ap); /* flush */
-
- switch (qc->tf.protocol) {
- case ATAPI_PROT_PIO:
- ap->hsm_task_state = HSM_ST;
- break;
- case ATAPI_PROT_NODATA:
- ap->hsm_task_state = HSM_ST_LAST;
- break;
- case ATAPI_PROT_DMA:
- ap->hsm_task_state = HSM_ST_LAST;
- /* initiate bmdma */
- ap->ops->bmdma_start(qc);
- break;
- }
-}
-
-/**
- * __atapi_pio_bytes - Transfer data from/to the ATAPI device.
- * @qc: Command on going
- * @bytes: number of bytes
- *
- * Transfer Transfer data from/to the ATAPI device.
- *
- * LOCKING:
- * Inherited from caller.
- *
- */
-static int __atapi_pio_bytes(struct ata_queued_cmd *qc, unsigned int bytes)
-{
- int rw = (qc->tf.flags & ATA_TFLAG_WRITE) ? WRITE : READ;
- struct ata_port *ap = qc->ap;
- struct ata_device *dev = qc->dev;
- struct ata_eh_info *ehi = &dev->link->eh_info;
- struct scatterlist *sg;
- struct page *page;
- unsigned char *buf;
- unsigned int offset, count, consumed;
-
-next_sg:
- sg = qc->cursg;
- if (unlikely(!sg)) {
- ata_ehi_push_desc(ehi, "unexpected or too much trailing data "
- "buf=%u cur=%u bytes=%u",
- qc->nbytes, qc->curbytes, bytes);
- return -1;
- }
-
- page = sg_page(sg);
- offset = sg->offset + qc->cursg_ofs;
-
- /* get the current page and offset */
- page = nth_page(page, (offset >> PAGE_SHIFT));
- offset %= PAGE_SIZE;
-
- /* don't overrun current sg */
- count = min(sg->length - qc->cursg_ofs, bytes);
-
- /* don't cross page boundaries */
- count = min(count, (unsigned int)PAGE_SIZE - offset);
-
- DPRINTK("data %s\n", qc->tf.flags & ATA_TFLAG_WRITE ? "write" : "read");
-
- if (PageHighMem(page)) {
- unsigned long flags;
-
- /* FIXME: use bounce buffer */
- local_irq_save(flags);
- buf = kmap_atomic(page, KM_IRQ0);
-
- /* do the actual data transfer */
- consumed = ap->ops->data_xfer(dev, buf + offset, count, rw);
-
- kunmap_atomic(buf, KM_IRQ0);
- local_irq_restore(flags);
- } else {
- buf = page_address(page);
- consumed = ap->ops->data_xfer(dev, buf + offset, count, rw);
- }
-
- bytes -= min(bytes, consumed);
- qc->curbytes += count;
- qc->cursg_ofs += count;
-
- if (qc->cursg_ofs == sg->length) {
- qc->cursg = sg_next(qc->cursg);
- qc->cursg_ofs = 0;
- }
-
- /* consumed can be larger than count only for the last transfer */
- WARN_ON(qc->cursg && count != consumed);
-
- if (bytes)
- goto next_sg;
- return 0;
-}
-
-/**
- * atapi_pio_bytes - Transfer data from/to the ATAPI device.
- * @qc: Command on going
- *
- * Transfer Transfer data from/to the ATAPI device.
- *
- * LOCKING:
- * Inherited from caller.
- */
-
-static void atapi_pio_bytes(struct ata_queued_cmd *qc)
-{
- struct ata_port *ap = qc->ap;
- struct ata_device *dev = qc->dev;
- struct ata_eh_info *ehi = &dev->link->eh_info;
- unsigned int ireason, bc_lo, bc_hi, bytes;
- int i_write, do_write = (qc->tf.flags & ATA_TFLAG_WRITE) ? 1 : 0;
-
- /* Abuse qc->result_tf for temp storage of intermediate TF
- * here to save some kernel stack usage.
- * For normal completion, qc->result_tf is not relevant. For
- * error, qc->result_tf is later overwritten by ata_qc_complete().
- * So, the correctness of qc->result_tf is not affected.
- */
- ap->ops->tf_read(ap, &qc->result_tf);
- ireason = qc->result_tf.nsect;
- bc_lo = qc->result_tf.lbam;
- bc_hi = qc->result_tf.lbah;
- bytes = (bc_hi << 8) | bc_lo;
-
- /* shall be cleared to zero, indicating xfer of data */
- if (unlikely(ireason & (1 << 0)))
- goto atapi_check;
-
- /* make sure transfer direction matches expected */
- i_write = ((ireason & (1 << 1)) == 0) ? 1 : 0;
- if (unlikely(do_write != i_write))
- goto atapi_check;
-
- if (unlikely(!bytes))
- goto atapi_check;
-
- VPRINTK("ata%u: xfering %d bytes\n", ap->print_id, bytes);
-
- if (unlikely(__atapi_pio_bytes(qc, bytes)))
- goto err_out;
- ata_altstatus(ap); /* flush */
-
- return;
-
- atapi_check:
- ata_ehi_push_desc(ehi, "ATAPI check failed (ireason=0x%x bytes=%u)",
- ireason, bytes);
- err_out:
- qc->err_mask |= AC_ERR_HSM;
- ap->hsm_task_state = HSM_ST_ERR;
-}
-
-/**
- * ata_hsm_ok_in_wq - Check if the qc can be handled in the workqueue.
- * @ap: the target ata_port
- * @qc: qc on going
- *
- * RETURNS:
- * 1 if ok in workqueue, 0 otherwise.
- */
-
-static inline int ata_hsm_ok_in_wq(struct ata_port *ap, struct ata_queued_cmd *qc)
-{
- if (qc->tf.flags & ATA_TFLAG_POLLING)
- return 1;
-
- if (ap->hsm_task_state == HSM_ST_FIRST) {
- if (qc->tf.protocol == ATA_PROT_PIO &&
- (qc->tf.flags & ATA_TFLAG_WRITE))
- return 1;
-
- if (ata_is_atapi(qc->tf.protocol) &&
- !(qc->dev->flags & ATA_DFLAG_CDB_INTR))
- return 1;
- }
-
- return 0;
-}
-
-/**
- * ata_hsm_qc_complete - finish a qc running on standard HSM
- * @qc: Command to complete
- * @in_wq: 1 if called from workqueue, 0 otherwise
- *
- * Finish @qc which is running on standard HSM.
- *
- * LOCKING:
- * If @in_wq is zero, spin_lock_irqsave(host lock).
- * Otherwise, none on entry and grabs host lock.
- */
-static void ata_hsm_qc_complete(struct ata_queued_cmd *qc, int in_wq)
-{
- struct ata_port *ap = qc->ap;
- unsigned long flags;
-
- if (ap->ops->error_handler) {
- if (in_wq) {
- spin_lock_irqsave(ap->lock, flags);
-
- /* EH might have kicked in while host lock is
- * released.
- */
- qc = ata_qc_from_tag(ap, qc->tag);
- if (qc) {
- if (likely(!(qc->err_mask & AC_ERR_HSM))) {
- ap->ops->irq_on(ap);
- ata_qc_complete(qc);
- } else
- ata_port_freeze(ap);
- }
-
- spin_unlock_irqrestore(ap->lock, flags);
- } else {
- if (likely(!(qc->err_mask & AC_ERR_HSM)))
- ata_qc_complete(qc);
- else
- ata_port_freeze(ap);
- }
- } else {
- if (in_wq) {
- spin_lock_irqsave(ap->lock, flags);
- ap->ops->irq_on(ap);
- ata_qc_complete(qc);
- spin_unlock_irqrestore(ap->lock, flags);
- } else
- ata_qc_complete(qc);
- }
-}
-
-/**
- * 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.
- */
-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 != ata_hsm_ok_in_wq(ap, qc));
-
-fsm_start:
- DPRINTK("ata%u: protocol %d task_state %d (dev_stat 0x%X)\n",
- ap->print_id, qc->tf.protocol, ap->hsm_task_state, status);
-
- 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_DRQ) == 0)) {
- /* handle BSY=0, DRQ=0 as error */
- if (likely(status & (ATA_ERR | ATA_DF)))
- /* device stops HSM for abort/error */
- qc->err_mask |= AC_ERR_DEV;
- else
- /* HSM violation. Let EH handle this */
- qc->err_mask |= AC_ERR_HSM;
-
- ap->hsm_task_state = HSM_ST_ERR;
- goto fsm_start;
- }
-
- /* Device should not ask for data transfer (DRQ=1)
- * when it finds something wrong.
- * We ignore DRQ here and stop the HSM by
- * changing hsm_task_state to HSM_ST_ERR and
- * let the EH abort the command or reset the device.
- */
- if (unlikely(status & (ATA_ERR | ATA_DF))) {
- /* Some ATAPI tape drives forget to clear the ERR bit
- * when doing the next command (mostly request sense).
- * We ignore ERR here to workaround and proceed sending
- * the CDB.
- */
- if (!(qc->dev->horkage & ATA_HORKAGE_STUCK_ERR)) {
- ata_port_printk(ap, KERN_WARNING,
- "DRQ=1 with device error, "
- "dev_stat 0x%X\n", status);
- qc->err_mask |= AC_ERR_HSM;
- ap->hsm_task_state = HSM_ST_ERR;
- goto fsm_start;
- }
- }
-
- /* 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->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);
- } else
- /* send CDB */
- atapi_send_cdb(ap, qc);
-
- if (in_wq)
- spin_unlock_irqrestore(ap->lock, flags);
-
- /* if polling, ata_pio_task() handles the rest.
- * otherwise, interrupt handler takes over from here.
- */
- break;
-
- case HSM_ST:
- /* complete command or read/write the data register */
- if (qc->tf.protocol == ATAPI_PROT_PIO) {
- /* ATAPI PIO protocol */
- if ((status & ATA_DRQ) == 0) {
- /* No more data to transfer or device error.
- * Device error will be tagged in HSM_ST_LAST.
- */
- ap->hsm_task_state = HSM_ST_LAST;
- goto fsm_start;
- }
-
- /* Device should not ask for data transfer (DRQ=1)
- * when it finds something wrong.
- * We ignore DRQ here and stop the HSM by
- * changing hsm_task_state to HSM_ST_ERR and
- * let the EH abort the command or reset the device.
- */
- if (unlikely(status & (ATA_ERR | ATA_DF))) {
- ata_port_printk(ap, KERN_WARNING, "DRQ=1 with "
- "device error, dev_stat 0x%X\n",
- status);
- qc->err_mask |= AC_ERR_HSM;
- ap->hsm_task_state = HSM_ST_ERR;
- goto fsm_start;
- }
-
- atapi_pio_bytes(qc);
-
- if (unlikely(ap->hsm_task_state == HSM_ST_ERR))
- /* bad ireason reported by device */
- goto fsm_start;
-
- } else {
- /* ATA PIO protocol */
- if (unlikely((status & ATA_DRQ) == 0)) {
- /* handle BSY=0, DRQ=0 as error */
- if (likely(status & (ATA_ERR | ATA_DF)))
- /* device stops HSM for abort/error */
- qc->err_mask |= AC_ERR_DEV;
- else
- /* HSM violation. Let EH handle this.
- * Phantom devices also trigger this
- * condition. Mark hint.
- */
- qc->err_mask |= AC_ERR_HSM |
- AC_ERR_NODEV_HINT;
-
- ap->hsm_task_state = HSM_ST_ERR;
- goto fsm_start;
- }
-
- /* For PIO reads, some devices may ask for
- * data transfer (DRQ=1) alone with ERR=1.
- * We respect DRQ here and transfer one
- * block of junk data before changing the
- * hsm_task_state to HSM_ST_ERR.
- *
- * For PIO writes, ERR=1 DRQ=1 doesn't make
- * sense since the data block has been
- * transferred to the device.
- */
- if (unlikely(status & (ATA_ERR | ATA_DF))) {
- /* data might be corrputed */
- qc->err_mask |= AC_ERR_DEV;
-
- if (!(qc->tf.flags & ATA_TFLAG_WRITE)) {
- ata_pio_sectors(qc);
- status = ata_wait_idle(ap);
- }
-
- if (status & (ATA_BUSY | ATA_DRQ))
- qc->err_mask |= AC_ERR_HSM;
-
- /* ata_pio_sectors() might change the
- * state to HSM_ST_LAST. so, the state
- * is changed after ata_pio_sectors().
- */
- ap->hsm_task_state = HSM_ST_ERR;
- goto fsm_start;
- }
-
- ata_pio_sectors(qc);
-
- if (ap->hsm_task_state == HSM_ST_LAST &&
- (!(qc->tf.flags & ATA_TFLAG_WRITE))) {
- /* all data read */
- status = ata_wait_idle(ap);
- goto fsm_start;
- }
- }
-
- poll_next = 1;
- break;
-
- case HSM_ST_LAST:
- if (unlikely(!ata_ok(status))) {
- qc->err_mask |= __ac_err_mask(status);
- ap->hsm_task_state = HSM_ST_ERR;
- goto fsm_start;
- }
-
- /* no more data to transfer */
- DPRINTK("ata%u: dev %u command complete, drv_stat 0x%x\n",
- ap->print_id, qc->dev->devno, status);
-
- WARN_ON(qc->err_mask);