[PATCH 3/4] block: add a str_to_blk_op helper

[Christoph Hellwig <hch@lst.de>]

Add a helper to find the REQ_OP_XYZ constant from the "XYZ" string.
This will be used for the error injection debugfs interface.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Keith Busch <kbusch@kernel.org>
Reviewed-by: Damien Le Moal <dlemoal@kernel.org>
Reviewed-by: Hannes Reinecke <hare@kernel.org>
---
 block/blk-core.c | 10 ++++++++++
 block/blk.h      |  1 +
 2 files changed, 11 insertions(+)

diff --git a/block/blk-core.c b/block/blk-core.c
index 7aa9cd110bdd..aa90aad6da13 100644
--- a/block/blk-core.c
+++ b/block/blk-core.c
@@ -132,6 +132,16 @@ inline const char *blk_op_str(enum req_op op)
 }
 EXPORT_SYMBOL_GPL(blk_op_str);
 
+enum req_op str_to_blk_op(const char *op)
+{
+	int i;
+
+	for (i = 0; i < ARRAY_SIZE(blk_op_name); i++)
+		if (blk_op_name[i] && !strcmp(blk_op_name[i], op))
+			return (enum req_op)i;
+	return REQ_OP_LAST;
+}
+
 #define ENT(_tag, _errno, _desc)	\
 [BLK_STS_##_tag] = {				\
 	.errno		= _errno,		\
diff --git a/block/blk.h b/block/blk.h
index 0eb8e932ec66..e8b7d5517086 100644
--- a/block/blk.h
+++ b/block/blk.h
@@ -52,6 +52,7 @@ void blk_free_flush_queue(struct blk_flush_queue *q);
 const char *blk_status_to_str(blk_status_t status);
 const char *blk_status_to_tag(blk_status_t status);
 blk_status_t tag_to_blk_status(const char *tag);
+enum req_op str_to_blk_op(const char *op);
 
 bool __blk_mq_unfreeze_queue(struct request_queue *q, bool force_atomic);
 bool blk_queue_start_drain(struct request_queue *q);
-- 
2.53.0