libata: reimplement link iterator

[safe/jmp/linux-2.6] / drivers / ata / libata-core.c

diff --git a/drivers/ata/libata-core.c b/drivers/ata/libata-core.c
index 79e3a8e..d156616 100644 (file)
--- 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
@@ -4868,10 +4897,8 @@ int sata_scr_valid(struct ata_link *link)
 int sata_scr_read(struct ata_link *link, int reg, u32 *val)
 {
        if (ata_is_host_link(link)) {
-               struct ata_port *ap = link->ap;
-
                if (sata_scr_valid(link))
-                       return ap->ops->scr_read(ap, reg, val);
+                       return link->ap->ops->scr_read(link, reg, val);
                return -EOPNOTSUPP;
        }
 
@@ -4897,10 +4924,8 @@ int sata_scr_read(struct ata_link *link, int reg, u32 *val)
 int sata_scr_write(struct ata_link *link, int reg, u32 val)
 {
        if (ata_is_host_link(link)) {
-               struct ata_port *ap = link->ap;
-
                if (sata_scr_valid(link))
-                       return ap->ops->scr_write(ap, reg, val);
+                       return link->ap->ops->scr_write(link, reg, val);
                return -EOPNOTSUPP;
        }
 
@@ -4925,13 +4950,12 @@ int sata_scr_write(struct ata_link *link, int reg, u32 val)
 int sata_scr_write_flush(struct ata_link *link, int reg, u32 val)
 {
        if (ata_is_host_link(link)) {
-               struct ata_port *ap = link->ap;
                int rc;
 
                if (sata_scr_valid(link)) {
-                       rc = ap->ops->scr_write(ap, reg, val);
+                       rc = link->ap->ops->scr_write(link, reg, val);
                        if (rc == 0)
-                               rc = ap->ops->scr_read(ap, reg, &val);
+                               rc = link->ap->ops->scr_read(link, reg, &val);
                        return rc;
                }
                return -EOPNOTSUPP;
@@ -6260,6 +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);