[IA64] fix section mismatch in arch/ia64/kernel/palinfo.c
[safe/jmp/linux-2.6] / block / elevator.c
index 4769a25..ac5310e 100644 (file)
@@ -45,7 +45,8 @@ static LIST_HEAD(elv_list);
  */
 static const int elv_hash_shift = 6;
 #define ELV_HASH_BLOCK(sec)    ((sec) >> 3)
-#define ELV_HASH_FN(sec)       (hash_long(ELV_HASH_BLOCK((sec)), elv_hash_shift))
+#define ELV_HASH_FN(sec)       \
+               (hash_long(ELV_HASH_BLOCK((sec)), elv_hash_shift))
 #define ELV_HASH_ENTRIES       (1 << elv_hash_shift)
 #define rq_hash_key(rq)                ((rq)->sector + (rq)->nr_sectors)
 #define ELV_ON_HASH(rq)                (!hlist_unhashed(&(rq)->hash))
@@ -56,7 +57,7 @@ static const int elv_hash_shift = 6;
  */
 static int elv_iosched_allow_merge(struct request *rq, struct bio *bio)
 {
-       request_queue_t *q = rq->q;
+       struct request_queue *q = rq->q;
        elevator_t *e = q->elevator;
 
        if (e->ops->elevator_allow_merge_fn)
@@ -68,7 +69,7 @@ static int elv_iosched_allow_merge(struct request *rq, struct bio *bio)
 /*
  * can we safely merge with this request?
  */
-inline int elv_rq_merge_ok(struct request *rq, struct bio *bio)
+int elv_rq_merge_ok(struct request *rq, struct bio *bio)
 {
        if (!rq_mergeable(rq))
                return 0;
@@ -133,6 +134,21 @@ static struct elevator_type *elevator_get(const char *name)
        spin_lock(&elv_list_lock);
 
        e = elevator_find(name);
+       if (!e) {
+               char elv[ELV_NAME_MAX + strlen("-iosched")];
+
+               spin_unlock(&elv_list_lock);
+
+               if (!strcmp(name, "anticipatory"))
+                       sprintf(elv, "as-iosched");
+               else
+                       sprintf(elv, "%s-iosched", name);
+
+               request_module(elv);
+               spin_lock(&elv_list_lock);
+               e = elevator_find(name);
+       }
+
        if (e && !try_module_get(e->elevator_owner))
                e = NULL;
 
@@ -141,12 +157,13 @@ static struct elevator_type *elevator_get(const char *name)
        return e;
 }
 
-static void *elevator_init_queue(request_queue_t *q, struct elevator_queue *eq)
+static void *elevator_init_queue(struct request_queue *q,
+                                struct elevator_queue *eq)
 {
        return eq->ops->elevator_init_fn(q);
 }
 
-static void elevator_attach(request_queue_t *q, struct elevator_queue *eq,
+static void elevator_attach(struct request_queue *q, struct elevator_queue *eq,
                           void *data)
 {
        q->elevator = eq;
@@ -172,21 +189,19 @@ __setup("elevator=", elevator_setup);
 
 static struct kobj_type elv_ktype;
 
-static elevator_t *elevator_alloc(request_queue_t *q, struct elevator_type *e)
+static elevator_t *elevator_alloc(struct request_queue *q,
+                                 struct elevator_type *e)
 {
        elevator_t *eq;
        int i;
 
-       eq = kmalloc_node(sizeof(elevator_t), GFP_KERNEL, q->node);
+       eq = kmalloc_node(sizeof(elevator_t), GFP_KERNEL | __GFP_ZERO, q->node);
        if (unlikely(!eq))
                goto err;
 
-       memset(eq, 0, sizeof(*eq));
        eq->ops = &e->ops;
        eq->elevator_type = e;
-       kobject_init(&eq->kobj);
-       snprintf(eq->kobj.name, KOBJ_NAME_LEN, "%s", "iosched");
-       eq->kobj.ktype = &elv_ktype;
+       kobject_init(&eq->kobj, &elv_ktype);
        mutex_init(&eq->sysfs_lock);
 
        eq->hash = kmalloc_node(sizeof(struct hlist_head) * ELV_HASH_ENTRIES,
@@ -213,7 +228,7 @@ static void elevator_release(struct kobject *kobj)
        kfree(e);
 }
 
-int elevator_init(request_queue_t *q, char *name)
+int elevator_init(struct request_queue *q, char *name)
 {
        struct elevator_type *e = NULL;
        struct elevator_queue *eq;
@@ -225,15 +240,27 @@ int elevator_init(request_queue_t *q, char *name)
        q->end_sector = 0;
        q->boundary_rq = NULL;
 
-       if (name && !(e = elevator_get(name)))
-               return -EINVAL;
+       if (name) {
+               e = elevator_get(name);
+               if (!e)
+                       return -EINVAL;
+       }
 
-       if (!e && *chosen_elevator && !(e = elevator_get(chosen_elevator)))
-               printk("I/O scheduler %s not found\n", chosen_elevator);
+       if (!e && *chosen_elevator) {
+               e = elevator_get(chosen_elevator);
+               if (!e)
+                       printk(KERN_ERR "I/O scheduler %s not found\n",
+                                                       chosen_elevator);
+       }
 
-       if (!e && !(e = elevator_get(CONFIG_DEFAULT_IOSCHED))) {
-               printk("Default I/O scheduler not found, using no-op\n");
-               e = elevator_get("noop");
+       if (!e) {
+               e = elevator_get(CONFIG_DEFAULT_IOSCHED);
+               if (!e) {
+                       printk(KERN_ERR
+                               "Default I/O scheduler not found. " \
+                               "Using noop.\n");
+                       e = elevator_get("noop");
+               }
        }
 
        eq = elevator_alloc(q, e);
@@ -249,7 +276,6 @@ int elevator_init(request_queue_t *q, char *name)
        elevator_attach(q, eq, data);
        return ret;
 }
-
 EXPORT_SYMBOL(elevator_init);
 
 void elevator_exit(elevator_t *e)
@@ -262,10 +288,9 @@ void elevator_exit(elevator_t *e)
 
        kobject_put(&e->kobj);
 }
-
 EXPORT_SYMBOL(elevator_exit);
 
-static void elv_activate_rq(request_queue_t *q, struct request *rq)
+static void elv_activate_rq(struct request_queue *q, struct request *rq)
 {
        elevator_t *e = q->elevator;
 
@@ -273,7 +298,7 @@ static void elv_activate_rq(request_queue_t *q, struct request *rq)
                e->ops->elevator_activate_req_fn(q, rq);
 }
 
-static void elv_deactivate_rq(request_queue_t *q, struct request *rq)
+static void elv_deactivate_rq(struct request_queue *q, struct request *rq)
 {
        elevator_t *e = q->elevator;
 
@@ -286,13 +311,13 @@ static inline void __elv_rqhash_del(struct request *rq)
        hlist_del_init(&rq->hash);
 }
 
-static void elv_rqhash_del(request_queue_t *q, struct request *rq)
+static void elv_rqhash_del(struct request_queue *q, struct request *rq)
 {
        if (ELV_ON_HASH(rq))
                __elv_rqhash_del(rq);
 }
 
-static void elv_rqhash_add(request_queue_t *q, struct request *rq)
+static void elv_rqhash_add(struct request_queue *q, struct request *rq)
 {
        elevator_t *e = q->elevator;
 
@@ -300,13 +325,13 @@ static void elv_rqhash_add(request_queue_t *q, struct request *rq)
        hlist_add_head(&rq->hash, &e->hash[ELV_HASH_FN(rq_hash_key(rq))]);
 }
 
-static void elv_rqhash_reposition(request_queue_t *q, struct request *rq)
+static void elv_rqhash_reposition(struct request_queue *q, struct request *rq)
 {
        __elv_rqhash_del(rq);
        elv_rqhash_add(q, rq);
 }
 
-static struct request *elv_rqhash_find(request_queue_t *q, sector_t offset)
+static struct request *elv_rqhash_find(struct request_queue *q, sector_t offset)
 {
        elevator_t *e = q->elevator;
        struct hlist_head *hash_list = &e->hash[ELV_HASH_FN(offset)];
@@ -354,7 +379,6 @@ struct request *elv_rb_add(struct rb_root *root, struct request *rq)
        rb_insert_color(&rq->rb_node, root);
        return NULL;
 }
-
 EXPORT_SYMBOL(elv_rb_add);
 
 void elv_rb_del(struct rb_root *root, struct request *rq)
@@ -363,7 +387,6 @@ void elv_rb_del(struct rb_root *root, struct request *rq)
        rb_erase(&rq->rb_node, root);
        RB_CLEAR_NODE(&rq->rb_node);
 }
-
 EXPORT_SYMBOL(elv_rb_del);
 
 struct request *elv_rb_find(struct rb_root *root, sector_t sector)
@@ -384,18 +407,18 @@ struct request *elv_rb_find(struct rb_root *root, sector_t sector)
 
        return NULL;
 }
-
 EXPORT_SYMBOL(elv_rb_find);
 
 /*
  * Insert rq into dispatch queue of q.  Queue lock must be held on
- * entry.  rq is sort insted into the dispatch queue. To be used by
+ * entry.  rq is sort instead into the dispatch queue. To be used by
  * specific elevators.
  */
-void elv_dispatch_sort(request_queue_t *q, struct request *rq)
+void elv_dispatch_sort(struct request_queue *q, struct request *rq)
 {
        sector_t boundary;
        struct list_head *entry;
+       int stop_flags;
 
        if (q->last_merge == rq)
                q->last_merge = NULL;
@@ -405,13 +428,13 @@ void elv_dispatch_sort(request_queue_t *q, struct request *rq)
        q->nr_sorted--;
 
        boundary = q->end_sector;
-
+       stop_flags = REQ_SOFTBARRIER | REQ_HARDBARRIER | REQ_STARTED;
        list_for_each_prev(entry, &q->queue_head) {
                struct request *pos = list_entry_rq(entry);
 
                if (rq_data_dir(rq) != rq_data_dir(pos))
                        break;
-               if (pos->cmd_flags & (REQ_SOFTBARRIER|REQ_HARDBARRIER|REQ_STARTED))
+               if (pos->cmd_flags & stop_flags)
                        break;
                if (rq->sector >= boundary) {
                        if (pos->sector < boundary)
@@ -426,7 +449,6 @@ void elv_dispatch_sort(request_queue_t *q, struct request *rq)
 
        list_add(&rq->queuelist, entry);
 }
-
 EXPORT_SYMBOL(elv_dispatch_sort);
 
 /*
@@ -447,10 +469,9 @@ void elv_dispatch_add_tail(struct request_queue *q, struct request *rq)
        q->boundary_rq = rq;
        list_add_tail(&rq->queuelist, &q->queue_head);
 }
-
 EXPORT_SYMBOL(elv_dispatch_add_tail);
 
-int elv_merge(request_queue_t *q, struct request **req, struct bio *bio)
+int elv_merge(struct request_queue *q, struct request **req, struct bio *bio)
 {
        elevator_t *e = q->elevator;
        struct request *__rq;
@@ -467,6 +488,9 @@ int elv_merge(request_queue_t *q, struct request **req, struct bio *bio)
                }
        }
 
+       if (blk_queue_nomerges(q))
+               return ELEVATOR_NO_MERGE;
+
        /*
         * See if our hash lookup can find a potential backmerge.
         */
@@ -482,7 +506,7 @@ int elv_merge(request_queue_t *q, struct request **req, struct bio *bio)
        return ELEVATOR_NO_MERGE;
 }
 
-void elv_merged_request(request_queue_t *q, struct request *rq, int type)
+void elv_merged_request(struct request_queue *q, struct request *rq, int type)
 {
        elevator_t *e = q->elevator;
 
@@ -495,7 +519,7 @@ void elv_merged_request(request_queue_t *q, struct request *rq, int type)
        q->last_merge = rq;
 }
 
-void elv_merge_requests(request_queue_t *q, struct request *rq,
+void elv_merge_requests(struct request_queue *q, struct request *rq,
                             struct request *next)
 {
        elevator_t *e = q->elevator;
@@ -510,7 +534,7 @@ void elv_merge_requests(request_queue_t *q, struct request *rq,
        q->last_merge = rq;
 }
 
-void elv_requeue_request(request_queue_t *q, struct request *rq)
+void elv_requeue_request(struct request_queue *q, struct request *rq)
 {
        /*
         * it already went through dequeue, we need to decrement the
@@ -527,7 +551,7 @@ void elv_requeue_request(request_queue_t *q, struct request *rq)
        elv_insert(q, rq, ELEVATOR_INSERT_REQUEUE);
 }
 
-static void elv_drain_elevator(request_queue_t *q)
+static void elv_drain_elevator(struct request_queue *q)
 {
        static int printed;
        while (q->elevator->ops->elevator_dispatch_fn(q, 1))
@@ -541,7 +565,7 @@ static void elv_drain_elevator(request_queue_t *q)
        }
 }
 
-void elv_insert(request_queue_t *q, struct request *rq, int where)
+void elv_insert(struct request_queue *q, struct request *rq, int where)
 {
        struct list_head *pos;
        unsigned ordseq;
@@ -639,7 +663,7 @@ void elv_insert(request_queue_t *q, struct request *rq, int where)
        }
 }
 
-void __elv_add_request(request_queue_t *q, struct request *rq, int where,
+void __elv_add_request(struct request_queue *q, struct request *rq, int where,
                       int plug)
 {
        if (q->ordcolor)
@@ -666,7 +690,8 @@ void __elv_add_request(request_queue_t *q, struct request *rq, int where,
                        q->end_sector = rq_end_sector(rq);
                        q->boundary_rq = rq;
                }
-       } else if (!(rq->cmd_flags & REQ_ELVPRIV) && where == ELEVATOR_INSERT_SORT)
+       } else if (!(rq->cmd_flags & REQ_ELVPRIV) &&
+                   where == ELEVATOR_INSERT_SORT)
                where = ELEVATOR_INSERT_BACK;
 
        if (plug)
@@ -674,10 +699,9 @@ void __elv_add_request(request_queue_t *q, struct request *rq, int where,
 
        elv_insert(q, rq, where);
 }
-
 EXPORT_SYMBOL(__elv_add_request);
 
-void elv_add_request(request_queue_t *q, struct request *rq, int where,
+void elv_add_request(struct request_queue *q, struct request *rq, int where,
                     int plug)
 {
        unsigned long flags;
@@ -686,10 +710,9 @@ void elv_add_request(request_queue_t *q, struct request *rq, int where,
        __elv_add_request(q, rq, where, plug);
        spin_unlock_irqrestore(q->queue_lock, flags);
 }
-
 EXPORT_SYMBOL(elv_add_request);
 
-static inline struct request *__elv_next_request(request_queue_t *q)
+static inline struct request *__elv_next_request(struct request_queue *q)
 {
        struct request *rq;
 
@@ -705,12 +728,20 @@ static inline struct request *__elv_next_request(request_queue_t *q)
        }
 }
 
-struct request *elv_next_request(request_queue_t *q)
+struct request *elv_next_request(struct request_queue *q)
 {
        struct request *rq;
        int ret;
 
        while ((rq = __elv_next_request(q)) != NULL) {
+               /*
+                * Kill the empty barrier place holder, the driver must
+                * not ever see it.
+                */
+               if (blk_empty_barrier(rq)) {
+                       end_queued_request(rq, 1);
+                       continue;
+               }
                if (!(rq->cmd_flags & REQ_STARTED)) {
                        /*
                         * This is the first time the device driver
@@ -734,7 +765,21 @@ struct request *elv_next_request(request_queue_t *q)
                        q->boundary_rq = NULL;
                }
 
-               if ((rq->cmd_flags & REQ_DONTPREP) || !q->prep_rq_fn)
+               if (rq->cmd_flags & REQ_DONTPREP)
+                       break;
+
+               if (q->dma_drain_size && rq->data_len) {
+                       /*
+                        * make sure space for the drain appears we
+                        * know we can do this because max_hw_segments
+                        * has been adjusted to be one fewer than the
+                        * device can handle
+                        */
+                       rq->nr_phys_segments++;
+                       rq->nr_hw_segments++;
+               }
+
+               if (!q->prep_rq_fn)
                        break;
 
                ret = q->prep_rq_fn(q, rq);
@@ -747,18 +792,21 @@ struct request *elv_next_request(request_queue_t *q)
                         * avoid resource deadlock.  REQ_STARTED will
                         * prevent other fs requests from passing this one.
                         */
+                       if (q->dma_drain_size && rq->data_len &&
+                           !(rq->cmd_flags & REQ_DONTPREP)) {
+                               /*
+                                * remove the space for the drain we added
+                                * so that we don't add it again
+                                */
+                               --rq->nr_phys_segments;
+                               --rq->nr_hw_segments;
+                       }
+
                        rq = NULL;
                        break;
                } else if (ret == BLKPREP_KILL) {
-                       int nr_bytes = rq->hard_nr_sectors << 9;
-
-                       if (!nr_bytes)
-                               nr_bytes = rq->data_len;
-
-                       blkdev_dequeue_request(rq);
                        rq->cmd_flags |= REQ_QUIET;
-                       end_that_request_chunk(rq, 0, nr_bytes);
-                       end_that_request_last(rq, 0);
+                       end_queued_request(rq, 0);
                } else {
                        printk(KERN_ERR "%s: bad return=%d\n", __FUNCTION__,
                                                                ret);
@@ -768,10 +816,9 @@ struct request *elv_next_request(request_queue_t *q)
 
        return rq;
 }
-
 EXPORT_SYMBOL(elv_next_request);
 
-void elv_dequeue_request(request_queue_t *q, struct request *rq)
+void elv_dequeue_request(struct request_queue *q, struct request *rq)
 {
        BUG_ON(list_empty(&rq->queuelist));
        BUG_ON(ELV_ON_HASH(rq));
@@ -786,10 +833,9 @@ void elv_dequeue_request(request_queue_t *q, struct request *rq)
        if (blk_account_rq(rq))
                q->in_flight++;
 }
-
 EXPORT_SYMBOL(elv_dequeue_request);
 
-int elv_queue_empty(request_queue_t *q)
+int elv_queue_empty(struct request_queue *q)
 {
        elevator_t *e = q->elevator;
 
@@ -801,10 +847,9 @@ int elv_queue_empty(request_queue_t *q)
 
        return 1;
 }
-
 EXPORT_SYMBOL(elv_queue_empty);
 
-struct request *elv_latter_request(request_queue_t *q, struct request *rq)
+struct request *elv_latter_request(struct request_queue *q, struct request *rq)
 {
        elevator_t *e = q->elevator;
 
@@ -813,7 +858,7 @@ struct request *elv_latter_request(request_queue_t *q, struct request *rq)
        return NULL;
 }
 
-struct request *elv_former_request(request_queue_t *q, struct request *rq)
+struct request *elv_former_request(struct request_queue *q, struct request *rq)
 {
        elevator_t *e = q->elevator;
 
@@ -822,7 +867,7 @@ struct request *elv_former_request(request_queue_t *q, struct request *rq)
        return NULL;
 }
 
-int elv_set_request(request_queue_t *q, struct request *rq, gfp_t gfp_mask)
+int elv_set_request(struct request_queue *q, struct request *rq, gfp_t gfp_mask)
 {
        elevator_t *e = q->elevator;
 
@@ -833,7 +878,7 @@ int elv_set_request(request_queue_t *q, struct request *rq, gfp_t gfp_mask)
        return 0;
 }
 
-void elv_put_request(request_queue_t *q, struct request *rq)
+void elv_put_request(struct request_queue *q, struct request *rq)
 {
        elevator_t *e = q->elevator;
 
@@ -841,7 +886,7 @@ void elv_put_request(request_queue_t *q, struct request *rq)
                e->ops->elevator_put_req_fn(rq);
 }
 
-int elv_may_queue(request_queue_t *q, int rw)
+int elv_may_queue(struct request_queue *q, int rw)
 {
        elevator_t *e = q->elevator;
 
@@ -851,7 +896,7 @@ int elv_may_queue(request_queue_t *q, int rw)
        return ELV_MQUEUE_MAY;
 }
 
-void elv_completed_request(request_queue_t *q, struct request *rq)
+void elv_completed_request(struct request_queue *q, struct request *rq)
 {
        elevator_t *e = q->elevator;
 
@@ -929,9 +974,7 @@ int elv_register_queue(struct request_queue *q)
        elevator_t *e = q->elevator;
        int error;
 
-       e->kobj.parent = &q->kobj;
-
-       error = kobject_add(&e->kobj);
+       error = kobject_add(&e->kobj, &q->kobj, "%s", "iosched");
        if (!error) {
                struct elv_fs_entry *attr = e->elevator_type->elevator_attrs;
                if (attr) {
@@ -958,7 +1001,7 @@ void elv_unregister_queue(struct request_queue *q)
                __elv_unregister_queue(q->elevator);
 }
 
-int elv_register(struct elevator_type *e)
+void elv_register(struct elevator_type *e)
 {
        char *def = "";
 
@@ -972,8 +1015,8 @@ int elv_register(struct elevator_type *e)
                         !strcmp(e->elevator_name, CONFIG_DEFAULT_IOSCHED)))
                                def = " (default)";
 
-       printk(KERN_INFO "io scheduler %s registered%s\n", e->elevator_name, def);
-       return 0;
+       printk(KERN_INFO "io scheduler %s registered%s\n", e->elevator_name,
+                                                               def);
 }
 EXPORT_SYMBOL_GPL(elv_register);
 
@@ -1007,7 +1050,7 @@ EXPORT_SYMBOL_GPL(elv_unregister);
  * need for the new one. this way we have a chance of going back to the old
  * one, if the new one fails init for some reason.
  */
-static int elevator_switch(request_queue_t *q, struct elevator_type *new_e)
+static int elevator_switch(struct request_queue *q, struct elevator_type *new_e)
 {
        elevator_t *old_elevator, *e;
        void *data;
@@ -1030,7 +1073,7 @@ static int elevator_switch(request_queue_t *q, struct elevator_type *new_e)
         */
        spin_lock_irq(q->queue_lock);
 
-       set_bit(QUEUE_FLAG_ELVSWITCH, &q->queue_flags);
+       queue_flag_set(QUEUE_FLAG_ELVSWITCH, q);
 
        elv_drain_elevator(q);
 
@@ -1064,7 +1107,10 @@ static int elevator_switch(request_queue_t *q, struct elevator_type *new_e)
         * finally exit old elevator and turn off BYPASS.
         */
        elevator_exit(old_elevator);
-       clear_bit(QUEUE_FLAG_ELVSWITCH, &q->queue_flags);
+       spin_lock_irq(q->queue_lock);
+       queue_flag_clear(QUEUE_FLAG_ELVSWITCH, q);
+       spin_unlock_irq(q->queue_lock);
+
        return 1;
 
 fail_register:
@@ -1075,11 +1121,16 @@ fail_register:
        elevator_exit(e);
        q->elevator = old_elevator;
        elv_register_queue(q);
-       clear_bit(QUEUE_FLAG_ELVSWITCH, &q->queue_flags);
+
+       spin_lock_irq(q->queue_lock);
+       queue_flag_clear(QUEUE_FLAG_ELVSWITCH, q);
+       spin_unlock_irq(q->queue_lock);
+
        return 0;
 }
 
-ssize_t elv_iosched_store(request_queue_t *q, const char *name, size_t count)
+ssize_t elv_iosched_store(struct request_queue *q, const char *name,
+                         size_t count)
 {
        char elevator_name[ELV_NAME_MAX];
        size_t len;
@@ -1104,11 +1155,12 @@ ssize_t elv_iosched_store(request_queue_t *q, const char *name, size_t count)
        }
 
        if (!elevator_switch(q, e))
-               printk(KERN_ERR "elevator: switch to %s failed\n",elevator_name);
+               printk(KERN_ERR "elevator: switch to %s failed\n",
+                                                       elevator_name);
        return count;
 }
 
-ssize_t elv_iosched_show(request_queue_t *q, char *name)
+ssize_t elv_iosched_show(struct request_queue *q, char *name)
 {
        elevator_t *e = q->elevator;
        struct elevator_type *elv = e->elevator_type;
@@ -1128,7 +1180,8 @@ ssize_t elv_iosched_show(request_queue_t *q, char *name)
        return len;
 }
 
-struct request *elv_rb_former_request(request_queue_t *q, struct request *rq)
+struct request *elv_rb_former_request(struct request_queue *q,
+                                     struct request *rq)
 {
        struct rb_node *rbprev = rb_prev(&rq->rb_node);
 
@@ -1137,10 +1190,10 @@ struct request *elv_rb_former_request(request_queue_t *q, struct request *rq)
 
        return NULL;
 }
-
 EXPORT_SYMBOL(elv_rb_former_request);
 
-struct request *elv_rb_latter_request(request_queue_t *q, struct request *rq)
+struct request *elv_rb_latter_request(struct request_queue *q,
+                                     struct request *rq)
 {
        struct rb_node *rbnext = rb_next(&rq->rb_node);
 
@@ -1149,5 +1202,4 @@ struct request *elv_rb_latter_request(request_queue_t *q, struct request *rq)
 
        return NULL;
 }
-
 EXPORT_SYMBOL(elv_rb_latter_request);