1 files changed, 48 insertions, 1 deletions

diff --git a/include/linux/blkdev.h b/include/linux/blkdev.h
index 90097dd8b8ed..b4415feac679 100644
--- a/include/linux/blkdev.h
+++ b/include/linux/blkdev.h
@@ -78,6 +78,50 @@ enum rq_cmd_type_bits {
         REQ_TYPE_DRV_PRIV,              /* driver defined types from here */
 };
 
+/*
+ * request flags */
+typedef __u32 __bitwise req_flags_t;
+
+/* elevator knows about this request */
+#define RQF_SORTED              ((__force req_flags_t)(1 << 0))
+/* drive already may have started this one */
+#define RQF_STARTED             ((__force req_flags_t)(1 << 1))
+/* uses tagged queueing */
+#define RQF_QUEUED              ((__force req_flags_t)(1 << 2))
+/* may not be passed by ioscheduler */
+#define RQF_SOFTBARRIER         ((__force req_flags_t)(1 << 3))
+/* request for flush sequence */
+#define RQF_FLUSH_SEQ           ((__force req_flags_t)(1 << 4))
+/* merge of different types, fail separately */
+#define RQF_MIXED_MERGE         ((__force req_flags_t)(1 << 5))
+/* track inflight for MQ */
+#define RQF_MQ_INFLIGHT         ((__force req_flags_t)(1 << 6))
+/* don't call prep for this one */
+#define RQF_DONTPREP            ((__force req_flags_t)(1 << 7))
+/* set for "ide_preempt" requests and also for requests for which the SCSI
+   "quiesce" state must be ignored. */
+#define RQF_PREEMPT             ((__force req_flags_t)(1 << 8))
+/* contains copies of user pages */
+#define RQF_COPY_USER           ((__force req_flags_t)(1 << 9))
+/* vaguely specified driver internal error.  Ignored by the block layer */
+#define RQF_FAILED              ((__force req_flags_t)(1 << 10))
+/* don't warn about errors */
+#define RQF_QUIET               ((__force req_flags_t)(1 << 11))
+/* elevator private data attached */
+#define RQF_ELVPRIV             ((__force req_flags_t)(1 << 12))
+/* account I/O stat */
+#define RQF_IO_STAT             ((__force req_flags_t)(1 << 13))
+/* request came from our alloc pool */
+#define RQF_ALLOCED             ((__force req_flags_t)(1 << 14))
+/* runtime pm request */
+#define RQF_PM                  ((__force req_flags_t)(1 << 15))
+/* on IO scheduler merge hash */
+#define RQF_HASHED              ((__force req_flags_t)(1 << 16))
+
+/* flags that prevent us from merging requests: */
+#define RQF_NOMERGE_FLAGS \
+        (RQF_STARTED | RQF_SOFTBARRIER | RQF_FLUSH_SEQ)
+
 #define BLK_MAX_CDB     16
 
 /*
@@ -99,6 +143,7 @@ struct request {
         int cpu;
         unsigned cmd_type;
         u64 cmd_flags;
+        req_flags_t rq_flags;
         unsigned long atomic_flags;
 
         /* the following two fields are internal, NEVER access directly */
@@ -648,7 +693,7 @@ static inline void queue_flag_clear(unsigned int flag, struct request_queue *q)
                              REQ_FAILFAST_DRIVER))
 
 #define blk_account_rq(rq) \
-        (((rq)->cmd_flags & REQ_STARTED) && \
+        (((rq)->rq_flags & RQF_STARTED) && \
          ((rq)->cmd_type == REQ_TYPE_FS))
 
 #define blk_rq_cpu_valid(rq)    ((rq)->cpu != -1)
@@ -740,6 +785,8 @@ static inline bool rq_mergeable(struct request *rq)
 
         if (rq->cmd_flags & REQ_NOMERGE_FLAGS)
                 return false;
+        if (rq->rq_flags & RQF_NOMERGE_FLAGS)
+                return false;
 
         return true;
 }