libata-pmp-prep: implement ATA_LFLAG_NO_RETRY

Some PMP links are connected to internal pseudo devices which may come
and go depending on situation.  There's no reason to try hard to
recover them.  ATA_LFLAG_NO_RETRY tells EH to not retry if the device
attached to the link fails.

Signed-off-by: Tejun Heo <htejun@gmail.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>

2 files changed, 5 insertions, 1 deletions

diff --git a/drivers/ata/libata-eh.c b/drivers/ata/libata-eh.c
index 7be04bd30bfe..8f8ed4dfb171 100644
--- a/drivers/ata/libata-eh.c
+++ b/drivers/ata/libata-eh.c
@@ -2335,7 +2335,10 @@ int ata_eh_recover(struct ata_port *ap, ata_prereset_fn_t prereset,
                 struct ata_eh_context *ehc = &link->eh_context;
 
                 ata_link_for_each_dev(dev, link) {
-                        ehc->tries[dev->devno] = ATA_EH_DEV_TRIES;
+                        if (link->flags & ATA_LFLAG_NO_RETRY)
+                                ehc->tries[dev->devno] = 1;
+                        else
+                                ehc->tries[dev->devno] = ATA_EH_DEV_TRIES;
 
                         /* collect port action mask recorded in dev actions */
                         ehc->i.action |= ehc->i.dev_action[dev->devno] &
diff --git a/include/linux/libata.h b/include/linux/libata.h
index 6266fffb0eb3..adeee7397cdb 100644
--- a/include/linux/libata.h
+++ b/include/linux/libata.h
@@ -169,6 +169,7 @@ enum {
         ATA_LFLAG_ASSUME_ATA    = (1 << 3), /* assume ATA class */
         ATA_LFLAG_ASSUME_SEMB   = (1 << 4), /* assume SEMB class */
         ATA_LFLAG_ASSUME_CLASS  = ATA_LFLAG_ASSUME_ATA | ATA_LFLAG_ASSUME_SEMB,
+        ATA_LFLAG_NO_RETRY      = (1 << 5), /* don't retry this link */
 
         /* struct ata_port flags */
         ATA_FLAG_SLAVE_POSS     = (1 << 0), /* host supports slave dev */