blob: 64d5291330312ac718ba7f649e3d428063127f39 [file] [log] [blame]
#include <linux/radix-tree.h>
#include <linux/rcupdate.h>
struct cfq_queue;
struct cfq_io_context {
void *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;
unsigned short cgroup_changed;
* 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 *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)) {
return ioc;
return NULL;
struct task_struct;
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);
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;