libata: clean up EH speed down implementation

Clean up EH speed down implementation.

* is_io boolean variable is replaced eflags.  is_io is ATA_EFLAG_IS_IO.

* Error categories now have names.

* Better comments.

* Reorder 5min and 10min rules in ata_eh_speed_down_verdict()

* Use local variable @link to cache @dev->link in ata_eh_speed_down()

These changes are to improve readability and ease further changes.
This patch doesn't introduce any behavior change.

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

1 files changed, 1 insertions, 1 deletions

diff --git a/include/linux/libata.h b/include/linux/libata.h
index ca347b018649..74f1255e2524 100644
--- a/include/linux/libata.h
+++ b/include/linux/libata.h
@@ -482,7 +482,7 @@ struct ata_port_stats {
 };
 
 struct ata_ering_entry {
-        int                     is_io;
+        unsigned int            eflags;
         unsigned int            err_mask;
         u64                     timestamp;
 };