block: add centralize REQ_OP_XXX to string helper
In order to centralize the REQ_OP_XXX to string conversion which can be
used in the block layer and different places in the kernel like f2fs,
this patch adds a new helper function along with an array similar to the
one present in the blk-mq-debugfs.c.
We keep this helper functionality centralize under blk-core.c instead of
blk-mq-debugfs.c since blk-core.c is configured using CONFIG_BLOCK and
it will not be dependent on blk-mq-debugfs.c which is configured using
CONFIG_BLK_DEBUG_FS.
Next patch adjusts the code in the blk-mq-debugfs.c with newly
introduced helper.
Reviewed-by: Bart Van Assche <bvanassche@acm.org>
Signed-off-by: Chaitanya Kulkarni <chaitanya.kulkarni@wdc.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
diff --git a/block/blk-core.c b/block/blk-core.c
index c97da29..129204d 100644
--- a/block/blk-core.c
+++ b/block/blk-core.c
@@ -120,6 +120,42 @@ void blk_rq_init(struct request_queue *q, struct request *rq)
}
EXPORT_SYMBOL(blk_rq_init);
+#define REQ_OP_NAME(name) [REQ_OP_##name] = #name
+static const char *const blk_op_name[] = {
+ REQ_OP_NAME(READ),
+ REQ_OP_NAME(WRITE),
+ REQ_OP_NAME(FLUSH),
+ REQ_OP_NAME(DISCARD),
+ REQ_OP_NAME(SECURE_ERASE),
+ REQ_OP_NAME(ZONE_RESET),
+ REQ_OP_NAME(WRITE_SAME),
+ REQ_OP_NAME(WRITE_ZEROES),
+ REQ_OP_NAME(SCSI_IN),
+ REQ_OP_NAME(SCSI_OUT),
+ REQ_OP_NAME(DRV_IN),
+ REQ_OP_NAME(DRV_OUT),
+};
+#undef REQ_OP_NAME
+
+/**
+ * blk_op_str - Return string XXX in the REQ_OP_XXX.
+ * @op: REQ_OP_XXX.
+ *
+ * Description: Centralize block layer function to convert REQ_OP_XXX into
+ * string format. Useful in the debugging and tracing bio or request. For
+ * invalid REQ_OP_XXX it returns string "UNKNOWN".
+ */
+inline const char *blk_op_str(unsigned int op)
+{
+ const char *op_str = "UNKNOWN";
+
+ if (op < ARRAY_SIZE(blk_op_name) && blk_op_name[op])
+ op_str = blk_op_name[op];
+
+ return op_str;
+}
+EXPORT_SYMBOL_GPL(blk_op_str);
+
static const struct {
int errno;
const char *name;
