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>

2 files changed, 38 insertions, 25 deletions

diff --git a/drivers/ata/libata-core.c b/drivers/ata/libata-core.c
index 825461a33abe..d156616f45f5 100644
--- a/drivers/ata/libata-core.c
+++ b/drivers/ata/libata-core.c
@@ -163,6 +163,35 @@ MODULE_LICENSE("GPL");
 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(ata_base_port_ops);
 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);
diff --git a/include/linux/libata.h b/include/linux/libata.h
index ffd622fa319c..3eaca347ce29 100644
--- a/include/linux/libata.h
+++ b/include/linux/libata.h
@@ -1265,34 +1265,17 @@ static inline int ata_link_active(struct ata_link *link)
         return ata_tag_valid(link->active_tag) || link->sactive;
 }
 
-static inline struct ata_link *ata_port_first_link(struct ata_port *ap)
-{
-        if (sata_pmp_attached(ap))
-                return ap->pmp_link;
-        return &ap->link;
-}
-
-static inline struct ata_link *ata_port_next_link(struct ata_link *link)
-{
-        struct ata_port *ap = link->ap;
-
-        if (ata_is_host_link(link)) {
-                if (!sata_pmp_attached(ap))
-                        return NULL;
-                return ap->pmp_link;
-        }
-
-        if (++link < ap->nr_pmp_links + ap->pmp_link)
-                return link;
-        return NULL;
-}
+extern struct ata_link *__ata_port_next_link(struct ata_port *ap,
+                                             struct ata_link *link,
+                                             bool dev_only);
 
-#define __ata_port_for_each_link(lk, ap) \
-        for ((lk) = &(ap)->link; (lk); (lk) = ata_port_next_link(lk))
+#define __ata_port_for_each_link(link, ap) \
+        for ((link) = __ata_port_next_link((ap), NULL, false); (link); \
+             (link) = __ata_port_next_link((ap), (link), false))
 
 #define ata_port_for_each_link(link, ap) \
-        for ((link) = ata_port_first_link(ap); (link); \
-             (link) = ata_port_next_link(link))
+        for ((link) = __ata_port_next_link((ap), NULL, true); (link); \
+             (link) = __ata_port_next_link((ap), (link), true))
 
 #define ata_link_for_each_dev(dev, link) \
         for ((dev) = (link)->device; \