[mirror_ubuntu-eoan-kernel.git] / include / linux / iocontext.h

#ifndef IOCONTEXT_H
#define IOCONTEXT_H

#include <linux/radix-tree.h>
#include <linux/rcupdate.h>

struct cfq_queue;
struct cfq_ttime {
	unsigned long last_end_request;

	unsigned long ttime_total;
	unsigned long ttime_samples;
	unsigned long ttime_mean;
};

struct cfq_io_context {
	void *key;
	struct request_queue *q;

	struct cfq_queue *cfqq[2];

	struct io_context *ioc;

	struct cfq_ttime ttime;

	struct list_head queue_list;
	struct hlist_node cic_list;

	void (*dtor)(struct io_context *); /* destructor */
	void (*exit)(struct io_context *); /* called on task exit */

	struct rcu_head rcu_head;
};

/*
 * I/O subsystem state of the associated processes.  It is refcounted
 * and kmalloc'ed. These could be shared between processes.
 */
struct io_context {
	atomic_long_t refcount;
	atomic_t nr_tasks;

	/* all the fields below are protected by this lock */
	spinlock_t lock;

	unsigned short ioprio;
	unsigned short ioprio_changed;

#if defined(CONFIG_BLK_CGROUP) || defined(CONFIG_BLK_CGROUP_MODULE)
	unsigned short cgroup_changed;
#endif

	/*
	 * For request batching
	 */
	int nr_batch_requests;     /* Number of requests left in the batch */
	unsigned long last_waited; /* Time last woken after wait for request */

	struct radix_tree_root radix_root;
	struct hlist_head cic_list;
	void __rcu *ioc_data;
};

static inline struct io_context *ioc_task_link(struct io_context *ioc)
{
	/*
	 * if ref count is zero, don't allow sharing (ioc is going away, it's
	 * a race).
	 */
	if (ioc && atomic_long_inc_not_zero(&ioc->refcount)) {
		atomic_inc(&ioc->nr_tasks);
		return ioc;
	}

	return NULL;
}

struct task_struct;
#ifdef CONFIG_BLOCK
void put_io_context(struct io_context *ioc);
void exit_io_context(struct task_struct *task);
struct io_context *get_task_io_context(struct task_struct *task,
				       gfp_t gfp_flags, int node);
#else
struct io_context;
static inline void put_io_context(struct io_context *ioc) { }
static inline void exit_io_context(struct task_struct *task) { }
#endif

#endif
Commit	Line	Data
fd0928df JA	1	#ifndef IOCONTEXT_H
	2	#define IOCONTEXT_H
	3
4ac845a2	4	#include <linux/radix-tree.h>
34e6bbf2	5	#include <linux/rcupdate.h>
4ac845a2	6
fd0928df	7	struct cfq_queue;
383cd721 SL	8	struct cfq_ttime {
	9	unsigned long last_end_request;
	10
	11	unsigned long ttime_total;
	12	unsigned long ttime_samples;
	13	unsigned long ttime_mean;
	14	};
	15
fd0928df	16	struct cfq_io_context {
fd0928df	17	void *key;
283287a5	18	struct request_queue *q;
fd0928df JA	19
	20	struct cfq_queue *cfqq[2];
	21
	22	struct io_context *ioc;
	23
383cd721	24	struct cfq_ttime ttime;
fd0928df	25
fd0928df	26	struct list_head queue_list;
ffc4e759	27	struct hlist_node cic_list;
fd0928df JA	28
	29	void (dtor)(struct io_context ); /* destructor */
	30	void (exit)(struct io_context ); /* called on task exit */
34e6bbf2 FC	31
34e6bbf2 FC	32	struct rcu_head rcu_head;
fd0928df JA	33	};
	34
	35	/*
d38ecf93 JA	36	* I/O subsystem state of the associated processes. It is refcounted
d38ecf93 JA	37	* and kmalloc'ed. These could be shared between processes.
fd0928df JA	38	*/
fd0928df JA	39	struct io_context {
d9c7d394	40	atomic_long_t refcount;
d38ecf93 JA	41	atomic_t nr_tasks;
	42
	43	/* all the fields below are protected by this lock */
	44	spinlock_t lock;
fd0928df JA	45
	46	unsigned short ioprio;
	47	unsigned short ioprio_changed;
	48
67523c48	49	#if defined(CONFIG_BLK_CGROUP) \|\| defined(CONFIG_BLK_CGROUP_MODULE)
31e4c28d VG	50	unsigned short cgroup_changed;
	51	#endif
	52
fd0928df JA	53	/*
	54	* For request batching
	55	*/
fd0928df	56	int nr_batch_requests; /* Number of requests left in the batch */
58c24a61	57	unsigned long last_waited; /* Time last woken after wait for request */
fd0928df	58
4ac845a2	59	struct radix_tree_root radix_root;
ffc4e759	60	struct hlist_head cic_list;
4d2deb40	61	void __rcu *ioc_data;
fd0928df JA	62	};
fd0928df JA	63
d38ecf93 JA	64	static inline struct io_context ioc_task_link(struct io_context ioc)
	65	{
	66	/*
	67	* if ref count is zero, don't allow sharing (ioc is going away, it's
	68	* a race).
	69	*/
d9c7d394	70	if (ioc && atomic_long_inc_not_zero(&ioc->refcount)) {
cbb4f264	71	atomic_inc(&ioc->nr_tasks);
d38ecf93	72	return ioc;
d237e5c7	73	}
d38ecf93 JA	74
	75	return NULL;
	76	}
	77
b69f2292	78	struct task_struct;
da9cbc87	79	#ifdef CONFIG_BLOCK
42ec57a8	80	void put_io_context(struct io_context *ioc);
b69f2292	81	void exit_io_context(struct task_struct *task);
6e736be7 TH	82	struct io_context get_task_io_context(struct task_struct task,
6e736be7 TH	83	gfp_t gfp_flags, int node);
da9cbc87	84	#else
da9cbc87	85	struct io_context;
42ec57a8 TH	86	static inline void put_io_context(struct io_context *ioc) { }
42ec57a8 TH	87	static inline void exit_io_context(struct task_struct *task) { }
da9cbc87 JA	88	#endif
da9cbc87 JA	89
fd0928df	90	#endif