libata: beef up iterators

There currently are the following looping constructs.

* __ata_port_for_each_link() for all available links
* ata_port_for_each_link() for edge links
* ata_link_for_each_dev() for all devices
* ata_link_for_each_dev_reverse() for all devices in reverse order

Now there's a need for looping construct which is similar to
__ata_port_for_each_link() but iterates over PMP links before the host
link.  Instead of adding another one with long name, do the following
cleanup.

* Implement and export ata_link_next() and ata_dev_next() which take
  @mode parameter and can be used to build custom loop.
* Implement ata_for_each_link() and ata_for_each_dev() which take
  looping mode explicitly.

The following iteration modes are implemented.

* ATA_LITER_EDGE		: loop over edge links
* ATA_LITER_HOST_FIRST		: loop over all links, host link first
* ATA_LITER_PMP_FIRST		: loop over all links, PMP links first

* ATA_DITER_ENABLED		: loop over enabled devices
* ATA_DITER_ENABLED_REVERSE	: loop over enabled devices in reverse order
* ATA_DITER_ALL			: loop over all devices
* ATA_DITER_ALL_REVERSE		: loop over all devices in reverse order

This change removes exlicit device enabledness checks from many loops
and makes it clear which ones are iterated over in which direction.

Signed-off-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Jeff Garzik <jgarzik@redhat.com>
This commit is contained in:
Tejun Heo
2008-11-03 20:03:17 +09:00
committed by Jeff Garzik
parent 3c92ec8ae9
commit 1eca4365be
15 changed files with 302 additions and 235 deletions

View File

@@ -465,24 +465,22 @@ static int it821x_smart_set_mode(struct ata_link *link, struct ata_device **unus
{
struct ata_device *dev;
ata_link_for_each_dev(dev, link) {
if (ata_dev_enabled(dev)) {
/* We don't really care */
dev->pio_mode = XFER_PIO_0;
dev->dma_mode = XFER_MW_DMA_0;
/* We do need the right mode information for DMA or PIO
and this comes from the current configuration flags */
if (ata_id_has_dma(dev->id)) {
ata_dev_printk(dev, KERN_INFO, "configured for DMA\n");
dev->xfer_mode = XFER_MW_DMA_0;
dev->xfer_shift = ATA_SHIFT_MWDMA;
dev->flags &= ~ATA_DFLAG_PIO;
} else {
ata_dev_printk(dev, KERN_INFO, "configured for PIO\n");
dev->xfer_mode = XFER_PIO_0;
dev->xfer_shift = ATA_SHIFT_PIO;
dev->flags |= ATA_DFLAG_PIO;
}
ata_for_each_dev(dev, link, ENABLED) {
/* We don't really care */
dev->pio_mode = XFER_PIO_0;
dev->dma_mode = XFER_MW_DMA_0;
/* We do need the right mode information for DMA or PIO
and this comes from the current configuration flags */
if (ata_id_has_dma(dev->id)) {
ata_dev_printk(dev, KERN_INFO, "configured for DMA\n");
dev->xfer_mode = XFER_MW_DMA_0;
dev->xfer_shift = ATA_SHIFT_MWDMA;
dev->flags &= ~ATA_DFLAG_PIO;
} else {
ata_dev_printk(dev, KERN_INFO, "configured for PIO\n");
dev->xfer_mode = XFER_PIO_0;
dev->xfer_shift = ATA_SHIFT_PIO;
dev->flags |= ATA_DFLAG_PIO;
}
}
return 0;