[PATCH 3/5] block: Provide blk_status_t decoding for retryable errors

[Keith Busch <keith.busch@intel.com>]

This patch provides a common decoder for block status that may be retried
so various entities wishing to consult this do not have to duplicate
this decision.

Signed-off-by: Keith Busch <keith.busch@intel.com>
---
 include/linux/blk_types.h | 16 ++++++++++++++++
 1 file changed, 16 insertions(+)

diff --git a/include/linux/blk_types.h b/include/linux/blk_types.h
index a1e628e032da..b6a8723b493c 100644
--- a/include/linux/blk_types.h
+++ b/include/linux/blk_types.h
@@ -39,6 +39,22 @@ typedef u8 __bitwise blk_status_t;
 
 #define BLK_STS_AGAIN		((__force blk_status_t)12)
 
+static inline bool blk_retryable(blk_status_t error)
+{
+	switch (error) {
+	case BLK_STS_NOTSUPP:
+	case BLK_STS_NOSPC:
+	case BLK_STS_TARGET:
+	case BLK_STS_NEXUS:
+	case BLK_STS_MEDIUM:
+	case BLK_STS_PROTECTION:
+		return false;
+	}
+
+	/* Anything else could be a path failure, so should be retried */
+	return true;
+}
+
 struct blk_issue_stat {
 	u64 stat;
 };
-- 
2.13.6