[GitHub/mt8127/android_kernel_alcatel_ttab.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_io_context {
	void *key;
	unsigned long dead_key;

	struct cfq_queue *cfqq[2];

	struct io_context *ioc;

	unsigned long last_end_request;

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

	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;

#ifdef CONFIG_BLK_CGROUP
	unsigned short cgroup_changed;
#endif

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

	struct radix_tree_root radix_root;
	struct hlist_head cic_list;
	void *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
int put_io_context(struct io_context *ioc);
void exit_io_context(struct task_struct *task);
struct io_context *get_io_context(gfp_t gfp_flags, int node);
struct io_context *alloc_io_context(gfp_t gfp_flags, int node);
void copy_io_context(struct io_context **pdst, struct io_context **psrc);
#else
static inline void exit_io_context(struct task_struct *task)
{
}

struct io_context;
static inline int put_io_context(struct io_context *ioc)
{
	return 1;
}
#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 JA	7	struct cfq_queue;
fd0928df JA	8	struct cfq_io_context {
fd0928df	9	void *key;
4ac845a2	10	unsigned long dead_key;
fd0928df JA	11
	12	struct cfq_queue *cfqq[2];
	13
	14	struct io_context *ioc;
	15
	16	unsigned long last_end_request;
fd0928df JA	17
	18	unsigned long ttime_total;
	19	unsigned long ttime_samples;
	20	unsigned long ttime_mean;
	21
fd0928df	22	struct list_head queue_list;
ffc4e759	23	struct hlist_node cic_list;
fd0928df JA	24
	25	void (dtor)(struct io_context ); /* destructor */
	26	void (exit)(struct io_context ); /* called on task exit */
34e6bbf2 FC	27
34e6bbf2 FC	28	struct rcu_head rcu_head;
fd0928df JA	29	};
	30
	31	/*
d38ecf93 JA	32	* I/O subsystem state of the associated processes. It is refcounted
d38ecf93 JA	33	* and kmalloc'ed. These could be shared between processes.
fd0928df JA	34	*/
fd0928df JA	35	struct io_context {
d9c7d394	36	atomic_long_t refcount;
d38ecf93 JA	37	atomic_t nr_tasks;
	38
	39	/* all the fields below are protected by this lock */
	40	spinlock_t lock;
fd0928df JA	41
	42	unsigned short ioprio;
	43	unsigned short ioprio_changed;
	44
31e4c28d VG	45	#ifdef CONFIG_BLK_CGROUP
	46	unsigned short cgroup_changed;
	47	#endif
	48
fd0928df JA	49	/*
	50	* For request batching
	51	*/
	52	unsigned long last_waited; /* Time last woken after wait for request */
	53	int nr_batch_requests; /* Number of requests left in the batch */
	54
4ac845a2	55	struct radix_tree_root radix_root;
ffc4e759	56	struct hlist_head cic_list;
fd0928df JA	57	void *ioc_data;
	58	};
	59
d38ecf93 JA	60	static inline struct io_context ioc_task_link(struct io_context ioc)
	61	{
	62	/*
	63	* if ref count is zero, don't allow sharing (ioc is going away, it's
	64	* a race).
	65	*/
d9c7d394	66	if (ioc && atomic_long_inc_not_zero(&ioc->refcount)) {
cbb4f264	67	atomic_inc(&ioc->nr_tasks);
d38ecf93	68	return ioc;
d237e5c7	69	}
d38ecf93 JA	70
	71	return NULL;
	72	}
	73
b69f2292	74	struct task_struct;
da9cbc87 JA	75	#ifdef CONFIG_BLOCK
da9cbc87 JA	76	int put_io_context(struct io_context *ioc);
b69f2292	77	void exit_io_context(struct task_struct *task);
da9cbc87 JA	78	struct io_context *get_io_context(gfp_t gfp_flags, int node);
	79	struct io_context *alloc_io_context(gfp_t gfp_flags, int node);
	80	void copy_io_context(struct io_context pdst, struct io_context psrc);
	81	#else
b69f2292	82	static inline void exit_io_context(struct task_struct *task)
da9cbc87 JA	83	{
	84	}
	85
	86	struct io_context;
	87	static inline int put_io_context(struct io_context *ioc)
	88	{
	89	return 1;
	90	}
	91	#endif
	92
fd0928df	93	#endif