X-Git-Url: http://git.onelab.eu/?a=blobdiff_plain;f=include%2Flinux%2Felevator.h;h=e88fcbc77f8f381d3c1b801955406f260b0cab4f;hb=refs%2Fheads%2Fvserver;hp=18cf1f3e11845dd6ba28f81b3defd2e4ed52adff;hpb=76828883507a47dae78837ab5dec5a5b4513c667;p=linux-2.6.git

diff --git a/include/linux/elevator.h b/include/linux/elevator.h
index 18cf1f3e1..e88fcbc77 100644
--- a/include/linux/elevator.h
+++ b/include/linux/elevator.h
@@ -1,12 +1,18 @@
 #ifndef _LINUX_ELEVATOR_H
 #define _LINUX_ELEVATOR_H
 
+#include <linux/percpu.h>
+
+#ifdef CONFIG_BLOCK
+
 typedef int (elevator_merge_fn) (request_queue_t *, struct request **,
 				 struct bio *);
 
 typedef void (elevator_merge_req_fn) (request_queue_t *, struct request *, struct request *);
 
-typedef void (elevator_merged_fn) (request_queue_t *, struct request *);
+typedef void (elevator_merged_fn) (request_queue_t *, struct request *, int);
+
+typedef int (elevator_allow_merge_fn) (request_queue_t *, struct request *, struct bio *);
 
 typedef int (elevator_dispatch_fn) (request_queue_t *, int);
 
@@ -14,14 +20,14 @@ typedef void (elevator_add_req_fn) (request_queue_t *, struct request *);
 typedef int (elevator_queue_empty_fn) (request_queue_t *);
 typedef struct request *(elevator_request_list_fn) (request_queue_t *, struct request *);
 typedef void (elevator_completed_req_fn) (request_queue_t *, struct request *);
-typedef int (elevator_may_queue_fn) (request_queue_t *, int, struct bio *);
+typedef int (elevator_may_queue_fn) (request_queue_t *, int);
 
-typedef int (elevator_set_req_fn) (request_queue_t *, struct request *, struct bio *, gfp_t);
-typedef void (elevator_put_req_fn) (request_queue_t *, struct request *);
+typedef int (elevator_set_req_fn) (request_queue_t *, struct request *, gfp_t);
+typedef void (elevator_put_req_fn) (struct request *);
 typedef void (elevator_activate_req_fn) (request_queue_t *, struct request *);
 typedef void (elevator_deactivate_req_fn) (request_queue_t *, struct request *);
 
-typedef int (elevator_init_fn) (request_queue_t *, elevator_t *);
+typedef void *(elevator_init_fn) (request_queue_t *);
 typedef void (elevator_exit_fn) (elevator_t *);
 
 struct elevator_ops
@@ -29,6 +35,7 @@ struct elevator_ops
 	elevator_merge_fn *elevator_merge_fn;
 	elevator_merged_fn *elevator_merged_fn;
 	elevator_merge_req_fn *elevator_merge_req_fn;
+	elevator_allow_merge_fn *elevator_allow_merge_fn;
 
 	elevator_dispatch_fn *elevator_dispatch_fn;
 	elevator_add_req_fn *elevator_add_req_fn;
@@ -48,10 +55,17 @@ 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)
 
+struct elv_fs_entry {
+	struct attribute attr;
+	ssize_t (*show)(elevator_t *, char *);
+	ssize_t (*store)(elevator_t *, const char *, size_t);
+};
+
 /*
  * identifies an elevator type, such as AS or deadline
  */
@@ -59,8 +73,7 @@ struct elevator_type
 {
 	struct list_head list;
 	struct elevator_ops ops;
-	struct elevator_type *elevator_type;
-	struct kobj_type *elevator_ktype;
+	struct elv_fs_entry *elevator_attrs;
 	char elevator_name[ELV_NAME_MAX];
 	struct module *elevator_owner;
 };
@@ -74,19 +87,22 @@ struct elevator_queue
 	void *elevator_data;
 	struct kobject kobj;
 	struct elevator_type *elevator_type;
+	struct mutex sysfs_lock;
+	struct hlist_head *hash;
 };
 
 /*
  * block elevator interface
  */
 extern void elv_dispatch_sort(request_queue_t *, struct request *);
+extern void elv_dispatch_add_tail(request_queue_t *, struct request *);
 extern void elv_add_request(request_queue_t *, struct request *, int, int);
 extern void __elv_add_request(request_queue_t *, struct request *, int, int);
 extern void elv_insert(request_queue_t *, struct request *, int);
 extern int elv_merge(request_queue_t *, struct request **, struct bio *);
 extern void elv_merge_requests(request_queue_t *, struct request *,
 			       struct request *);
-extern void elv_merged_request(request_queue_t *, struct request *);
+extern void elv_merged_request(request_queue_t *, struct request *, int);
 extern void elv_dequeue_request(request_queue_t *, struct request *);
 extern void elv_requeue_request(request_queue_t *, struct request *);
 extern int elv_queue_empty(request_queue_t *);
@@ -95,9 +111,9 @@ extern struct request *elv_former_request(request_queue_t *, struct request *);
 extern struct request *elv_latter_request(request_queue_t *, struct request *);
 extern int elv_register_queue(request_queue_t *q);
 extern void elv_unregister_queue(request_queue_t *q);
-extern int elv_may_queue(request_queue_t *, int, struct bio *);
+extern int elv_may_queue(request_queue_t *, int);
 extern void elv_completed_request(request_queue_t *, struct request *);
-extern int elv_set_request(request_queue_t *, struct request *, struct bio *, gfp_t);
+extern int elv_set_request(request_queue_t *, struct request *, gfp_t);
 extern void elv_put_request(request_queue_t *, struct request *);
 
 /*
@@ -116,6 +132,19 @@ extern int elevator_init(request_queue_t *, char *);
 extern void elevator_exit(elevator_t *);
 extern int elv_rq_merge_ok(struct request *, struct bio *);
 
+/*
+ * Helper functions.
+ */
+extern struct request *elv_rb_former_request(request_queue_t *, struct request *);
+extern struct request *elv_rb_latter_request(request_queue_t *, struct request *);
+
+/*
+ * rb support functions.
+ */
+extern struct request *elv_rb_add(struct rb_root *, struct request *);
+extern void elv_rb_del(struct rb_root *, struct request *);
+extern struct request *elv_rb_find(struct rb_root *, sector_t);
+
 /*
  * Return values from elevator merger
  */
@@ -141,5 +170,42 @@ enum {
 };
 
 #define rq_end_sector(rq)	((rq)->sector + (rq)->nr_sectors)
+#define rb_entry_rq(node)	rb_entry((node), struct request, rb_node)
+
+/*
+ * Hack to reuse the donelist list_head as the fifo time holder while
+ * the request is in the io scheduler. Saves an unsigned long in rq.
+ */
+#define rq_fifo_time(rq)	((unsigned long) (rq)->donelist.next)
+#define rq_set_fifo_time(rq,exp)	((rq)->donelist.next = (void *) (exp))
+#define rq_entry_fifo(ptr)	list_entry((ptr), struct request, queuelist)
+#define rq_fifo_clear(rq)	do {		\
+	list_del_init(&(rq)->queuelist);	\
+	INIT_LIST_HEAD(&(rq)->donelist);	\
+	} while (0)
 
+/*
+ * io context count accounting
+ */
+#define elv_ioc_count_mod(name, __val)				\
+	do {							\
+		preempt_disable();				\
+		__get_cpu_var(name) += (__val);			\
+		preempt_enable();				\
+	} while (0)
+
+#define elv_ioc_count_inc(name)	elv_ioc_count_mod(name, 1)
+#define elv_ioc_count_dec(name)	elv_ioc_count_mod(name, -1)
+
+#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