1 files changed, 19 insertions, 22 deletions

diff --git a/include/linux/elevator.h b/include/linux/elevator.h
index 1d0f7a2ff73b..c24f3d7fbf1e 100644
--- a/include/linux/elevator.h
+++ b/include/linux/elevator.h
@@ -5,6 +5,8 @@
 
 #ifdef CONFIG_BLOCK
 
+struct io_cq;
+
 typedef int (elevator_merge_fn) (struct request_queue *, struct request **,
                                  struct bio *);
 
@@ -24,6 +26,8 @@ typedef struct request *(elevator_request_list_fn) (struct request_queue *, stru
 typedef void (elevator_completed_req_fn) (struct request_queue *, struct request *);
 typedef int (elevator_may_queue_fn) (struct request_queue *, int);
 
+typedef void (elevator_init_icq_fn) (struct io_cq *);
+typedef void (elevator_exit_icq_fn) (struct io_cq *);
 typedef int (elevator_set_req_fn) (struct request_queue *, struct request *, gfp_t);
 typedef void (elevator_put_req_fn) (struct request *);
 typedef void (elevator_activate_req_fn) (struct request_queue *, struct request *);
@@ -56,6 +60,9 @@ struct elevator_ops
         elevator_request_list_fn *elevator_former_req_fn;
         elevator_request_list_fn *elevator_latter_req_fn;
 
+        elevator_init_icq_fn *elevator_init_icq_fn;     /* see iocontext.h */
+        elevator_exit_icq_fn *elevator_exit_icq_fn;     /* ditto */
+
         elevator_set_req_fn *elevator_set_req_fn;
         elevator_put_req_fn *elevator_put_req_fn;
 
@@ -63,7 +70,6 @@ struct elevator_ops
 
         elevator_init_fn *elevator_init_fn;
         elevator_exit_fn *elevator_exit_fn;
-        void (*trim)(struct io_context *);
 };
 
 #define ELV_NAME_MAX    (16)
@@ -79,11 +85,20 @@ struct elv_fs_entry {
  */
 struct elevator_type
 {
-        struct list_head list;
+        /* managed by elevator core */
+        struct kmem_cache *icq_cache;
+
+        /* fields provided by elevator implementation */
         struct elevator_ops ops;
+        size_t icq_size;        /* see iocontext.h */
+        size_t icq_align;       /* ditto */
         struct elv_fs_entry *elevator_attrs;
         char elevator_name[ELV_NAME_MAX];
         struct module *elevator_owner;
+
+        /* managed by elevator core */
+        char icq_cache_name[ELV_NAME_MAX + 5];  /* elvname + "_io_cq" */
+        struct list_head list;
 };
 
 /*
@@ -91,10 +106,9 @@ struct elevator_type
  */
 struct elevator_queue
 {
-        struct elevator_ops *ops;
+        struct elevator_type *type;
         void *elevator_data;
         struct kobject kobj;
-        struct elevator_type *elevator_type;
         struct mutex sysfs_lock;
         struct hlist_head *hash;
         unsigned int registered:1;
@@ -129,7 +143,7 @@ extern void elv_drain_elevator(struct request_queue *);
 /*
  * io scheduler registration
  */
-extern void elv_register(struct elevator_type *);
+extern int elv_register(struct elevator_type *);
 extern void elv_unregister(struct elevator_type *);
 
 /*
@@ -197,22 +211,5 @@ enum {
         INIT_LIST_HEAD(&(rq)->csd.list);        \
         } while (0)
 
-/*
- * io context count accounting
- */
-#define elv_ioc_count_mod(name, __val) this_cpu_add(name, __val)
-#define elv_ioc_count_inc(name) this_cpu_inc(name)
-#define elv_ioc_count_dec(name) this_cpu_dec(name)
-
-#define elv_ioc_count_read(name)                                \
-({                                                              \
-        unsigned long __val = 0;                                \
-        int __cpu;                                              \
-        smp_wmb();                                              \
-        for_each_possible_cpu(__cpu)                            \
-                __val += per_cpu(name, __cpu);                  \
-        __val;                                                  \
-})
-
 #endif /* CONFIG_BLOCK */
 #endif