[libata] improve device scan

Replace SCSI's legacy "bang at the door" method of probing with one
directly controlled by the underlying ATA transport layer.

We now only call scsi_scan_target() for devices we find, rather than
probing every possible channel/id within a certain range.

3 files changed, 14 insertions, 1 deletions

diff --git a/drivers/scsi/libata-core.c b/drivers/scsi/libata-core.c
index e5b01997117a..902c76364af7 100644
--- a/drivers/scsi/libata-core.c
+++ b/drivers/scsi/libata-core.c
@@ -4113,7 +4113,7 @@ int ata_device_add(struct ata_probe_ent *ent)
         for (i = 0; i < count; i++) {
                 struct ata_port *ap = host_set->ports[i];
 
-                scsi_scan_host(ap->host);
+                ata_scsi_scan_host(ap);
         }
 
         dev_set_drvdata(dev, host_set);
diff --git a/drivers/scsi/libata-scsi.c b/drivers/scsi/libata-scsi.c
index 104fd9a63e73..4fc0134d4272 100644
--- a/drivers/scsi/libata-scsi.c
+++ b/drivers/scsi/libata-scsi.c
@@ -1678,3 +1678,15 @@ void ata_scsi_simulate(u16 *id,
         }
 }
 
+void ata_scsi_scan_host(struct ata_port *ap)
+{
+        unsigned int i;
+
+        if (ap->flags & ATA_FLAG_PORT_DISABLED)
+                return;
+
+        for (i = 0; i < ATA_MAX_DEVICES; i++)
+                if (ata_dev_present(&ap->device[i]))
+                        scsi_scan_target(&ap->host->shost_gendev, 0, i, ~0, 0);
+}
+
diff --git a/drivers/scsi/libata.h b/drivers/scsi/libata.h
index d608b3a0f6fe..c7a1fa1c9abc 100644
--- a/drivers/scsi/libata.h
+++ b/drivers/scsi/libata.h
@@ -51,6 +51,7 @@ extern void swap_buf_le16(u16 *buf, unsigned int buf_words);
 
 
 /* libata-scsi.c */
+extern void ata_scsi_scan_host(struct ata_port *ap);
 extern void ata_to_sense_error(struct ata_queued_cmd *qc, u8 drv_stat);
 extern int ata_scsi_error(struct Scsi_Host *host);
 extern unsigned int ata_scsiop_inq_std(struct ata_scsi_args *args, u8 *rbuf,