libata: reimplement link iterator
Implement __ata_port_next_link() and reimplement
__ata_port_for_each_link() and ata_port_for_each_link() using it.
This removes relatively large inlined code and makes iteration easier
to extend.
Signed-off-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Jeff Garzik <jgarzik@redhat.com>
diff --git a/drivers/ata/libata-core.c b/drivers/ata/libata-core.c
index 825461a..d156616 100644
--- a/drivers/ata/libata-core.c
+++ b/drivers/ata/libata-core.c
@@ -163,6 +163,35 @@
MODULE_VERSION(DRV_VERSION);
+/*
+ * Iterator helpers. Don't use directly.
+ *
+ * LOCKING:
+ * Host lock or EH context.
+ */
+struct ata_link *__ata_port_next_link(struct ata_port *ap,
+ struct ata_link *link, bool dev_only)
+{
+ /* NULL link indicates start of iteration */
+ if (!link) {
+ if (dev_only && sata_pmp_attached(ap))
+ return ap->pmp_link;
+ return &ap->link;
+ }
+
+ /* we just iterated over the host link, what's next? */
+ if (ata_is_host_link(link)) {
+ if (!sata_pmp_attached(ap))
+ return NULL;
+ return ap->pmp_link;
+ }
+
+ /* iterate to the next PMP link */
+ if (++link < ap->pmp_link + ap->nr_pmp_links)
+ return link;
+ return NULL;
+}
+
/**
* ata_force_cbl - force cable type according to libata.force
* @ap: ATA port of interest
@@ -6255,6 +6284,7 @@
EXPORT_SYMBOL_GPL(sata_port_ops);
EXPORT_SYMBOL_GPL(ata_dummy_port_ops);
EXPORT_SYMBOL_GPL(ata_dummy_port_info);
+EXPORT_SYMBOL_GPL(__ata_port_next_link);
EXPORT_SYMBOL_GPL(ata_std_bios_param);
EXPORT_SYMBOL_GPL(ata_host_init);
EXPORT_SYMBOL_GPL(ata_host_alloc);