libata: Add a per-host flag to opt-in into parallel port probes
This patch adds a per host flag that allows drivers to opt in into
having its busses scanned in parallel.
Drivers that do not set this flag get their ports scanned in
the "original" sequence.
Signed-off-by: Arjan van de Ven <arjan@linux.intel.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/drivers/ata/ahci.c b/drivers/ata/ahci.c
index 7f701cb..9603967 100644
--- a/drivers/ata/ahci.c
+++ b/drivers/ata/ahci.c
@@ -2660,6 +2660,9 @@
host->iomap = pcim_iomap_table(pdev);
host->private_data = hpriv;
+ if (!(hpriv->cap & HOST_CAP_SSS))
+ host->flags |= ATA_HOST_PARALLEL_SCAN;
+
if (pi.flags & ATA_FLAG_EM)
ahci_reset_em(host);
diff --git a/drivers/ata/libata-core.c b/drivers/ata/libata-core.c
index c507a9a..f810078 100644
--- a/drivers/ata/libata-core.c
+++ b/drivers/ata/libata-core.c
@@ -5920,6 +5920,15 @@
{
int rc;
struct ata_port *ap = data;
+
+ /*
+ * If we're not allowed to scan this host in parallel,
+ * we need to wait until all previous scans have completed
+ * before going further.
+ */
+ if (!(ap->host->flags & ATA_HOST_PARALLEL_SCAN))
+ async_synchronize_cookie(cookie);
+
/* probe */
if (ap->ops->error_handler) {
struct ata_eh_info *ehi = &ap->link.eh_info;