#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);
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
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;
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
*/
{
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;
};
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 *);
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 *);
/*
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
*/
};
#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
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