1 files changed, 49 insertions, 17 deletions

diff --git a/include/linux/blkdev.h b/include/linux/blkdev.h
index 044467ef7b11..2755d5c6da22 100644
--- a/include/linux/blkdev.h
+++ b/include/linux/blkdev.h
@@ -38,6 +38,10 @@ struct request;
 typedef void (rq_end_io_fn)(struct request *, int);
 
 struct request_list {
+        /*
+         * count[], starved[], and wait[] are indexed by
+         * BLK_RW_SYNC/BLK_RW_ASYNC
+         */
         int count[2];
         int starved[2];
         int elvpriv;
@@ -66,6 +70,11 @@ enum rq_cmd_type_bits {
         REQ_TYPE_ATA_PC,
 };
 
+enum {
+        BLK_RW_ASYNC    = 0,
+        BLK_RW_SYNC     = 1,
+};
+
 /*
  * For request of type REQ_TYPE_LINUX_BLOCK, rq->cmd[0] is the opcode being
  * sent down (similar to how REQ_TYPE_BLOCK_PC means that ->cmd[] holds a
@@ -103,11 +112,13 @@ enum rq_flag_bits {
         __REQ_QUIET,            /* don't worry about errors */
         __REQ_PREEMPT,          /* set for "ide_preempt" requests */
         __REQ_ORDERED_COLOR,    /* is before or after barrier */
-        __REQ_RW_SYNC,          /* request is sync (O_DIRECT) */
+        __REQ_RW_SYNC,          /* request is sync (sync write or read) */
         __REQ_ALLOCED,          /* request came from our alloc pool */
         __REQ_RW_META,          /* metadata io request */
         __REQ_COPY_USER,        /* contains copies of user pages */
         __REQ_INTEGRITY,        /* integrity metadata has been remapped */
+        __REQ_NOIDLE,           /* Don't anticipate more IO after this one */
+        __REQ_IO_STAT,          /* account I/O stat */
         __REQ_NR_BITS,          /* stops here */
 };
 
@@ -134,6 +145,8 @@ enum rq_flag_bits {
 #define REQ_RW_META     (1 << __REQ_RW_META)
 #define REQ_COPY_USER   (1 << __REQ_COPY_USER)
 #define REQ_INTEGRITY   (1 << __REQ_INTEGRITY)
+#define REQ_NOIDLE      (1 << __REQ_NOIDLE)
+#define REQ_IO_STAT     (1 << __REQ_IO_STAT)
 
 #define BLK_MAX_CDB     16
 
@@ -436,8 +449,8 @@ struct request_queue
 #define QUEUE_FLAG_CLUSTER      0       /* cluster several segments into 1 */
 #define QUEUE_FLAG_QUEUED       1       /* uses generic tag queueing */
 #define QUEUE_FLAG_STOPPED      2       /* queue is stopped */
-#define QUEUE_FLAG_READFULL     3       /* read queue has been filled */
-#define QUEUE_FLAG_WRITEFULL    4       /* write queue has been filled */
+#define QUEUE_FLAG_SYNCFULL     3       /* read queue has been filled */
+#define QUEUE_FLAG_ASYNCFULL    4       /* write queue has been filled */
 #define QUEUE_FLAG_DEAD         5       /* queue being torn down */
 #define QUEUE_FLAG_REENTER      6       /* Re-entrancy avoidance */
 #define QUEUE_FLAG_PLUGGED      7       /* queue is plugged */
@@ -449,6 +462,11 @@ struct request_queue
 #define QUEUE_FLAG_STACKABLE   13       /* supports request stacking */
 #define QUEUE_FLAG_NONROT      14       /* non-rotational device (SSD) */
 #define QUEUE_FLAG_VIRT        QUEUE_FLAG_NONROT /* paravirt device */
+#define QUEUE_FLAG_IO_STAT     15       /* do IO stats */
+
+#define QUEUE_FLAG_DEFAULT      ((1 << QUEUE_FLAG_IO_STAT) |            \
+                                 (1 << QUEUE_FLAG_CLUSTER) |            \
+                                 (1 << QUEUE_FLAG_STACKABLE))
 
 static inline int queue_is_locked(struct request_queue *q)
 {
@@ -565,6 +583,7 @@ enum {
 #define blk_queue_stopped(q)    test_bit(QUEUE_FLAG_STOPPED, &(q)->queue_flags)
 #define blk_queue_nomerges(q)   test_bit(QUEUE_FLAG_NOMERGES, &(q)->queue_flags)
 #define blk_queue_nonrot(q)     test_bit(QUEUE_FLAG_NONROT, &(q)->queue_flags)
+#define blk_queue_io_stat(q)    test_bit(QUEUE_FLAG_IO_STAT, &(q)->queue_flags)
 #define blk_queue_flushing(q)   ((q)->ordseq)
 #define blk_queue_stackable(q)  \
         test_bit(QUEUE_FLAG_STACKABLE, &(q)->queue_flags)
@@ -581,6 +600,7 @@ enum {
                                  blk_failfast_transport(rq) ||  \
                                  blk_failfast_driver(rq))
 #define blk_rq_started(rq)      ((rq)->cmd_flags & REQ_STARTED)
+#define blk_rq_io_stat(rq)      ((rq)->cmd_flags & REQ_IO_STAT)
 
 #define blk_account_rq(rq)      (blk_rq_started(rq) && (blk_fs_request(rq) || blk_discard_rq(rq))) 
 
@@ -603,32 +623,42 @@ enum {
 #define rq_data_dir(rq)         ((rq)->cmd_flags & 1)
 
 /*
- * We regard a request as sync, if it's a READ or a SYNC write.
+ * We regard a request as sync, if either a read or a sync write
  */
-#define rq_is_sync(rq)          (rq_data_dir((rq)) == READ || (rq)->cmd_flags & REQ_RW_SYNC)
+static inline bool rw_is_sync(unsigned int rw_flags)
+{
+        return !(rw_flags & REQ_RW) || (rw_flags & REQ_RW_SYNC);
+}
+
+static inline bool rq_is_sync(struct request *rq)
+{
+        return rw_is_sync(rq->cmd_flags);
+}
+
 #define rq_is_meta(rq)          ((rq)->cmd_flags & REQ_RW_META)
+#define rq_noidle(rq)           ((rq)->cmd_flags & REQ_NOIDLE)
 
-static inline int blk_queue_full(struct request_queue *q, int rw)
+static inline int blk_queue_full(struct request_queue *q, int sync)
 {
-        if (rw == READ)
-                return test_bit(QUEUE_FLAG_READFULL, &q->queue_flags);
-        return test_bit(QUEUE_FLAG_WRITEFULL, &q->queue_flags);
+        if (sync)
+                return test_bit(QUEUE_FLAG_SYNCFULL, &q->queue_flags);
+        return test_bit(QUEUE_FLAG_ASYNCFULL, &q->queue_flags);
 }
 
-static inline void blk_set_queue_full(struct request_queue *q, int rw)
+static inline void blk_set_queue_full(struct request_queue *q, int sync)
 {
-        if (rw == READ)
-                queue_flag_set(QUEUE_FLAG_READFULL, q);
+        if (sync)
+                queue_flag_set(QUEUE_FLAG_SYNCFULL, q);
         else
-                queue_flag_set(QUEUE_FLAG_WRITEFULL, q);
+                queue_flag_set(QUEUE_FLAG_ASYNCFULL, q);
 }
 
-static inline void blk_clear_queue_full(struct request_queue *q, int rw)
+static inline void blk_clear_queue_full(struct request_queue *q, int sync)
 {
-        if (rw == READ)
-                queue_flag_clear(QUEUE_FLAG_READFULL, q);
+        if (sync)
+                queue_flag_clear(QUEUE_FLAG_SYNCFULL, q);
         else
-                queue_flag_clear(QUEUE_FLAG_WRITEFULL, q);
+                queue_flag_clear(QUEUE_FLAG_ASYNCFULL, q);
 }
 
 
@@ -700,6 +730,8 @@ struct req_iterator {
 };
 
 /* This should not be used directly - use rq_for_each_segment */
+#define for_each_bio(_bio)              \
+        for (; _bio; _bio = _bio->bi_next)
 #define __rq_for_each_bio(_bio, rq)     \
         if ((rq->bio))                  \
                 for (_bio = (rq)->bio; _bio; _bio = _bio->bi_next)