| #ifndef IOCONTEXT_H |
| #define IOCONTEXT_H |
| |
| #include <linux/radix-tree.h> |
| #include <linux/rcupdate.h> |
| #include <linux/workqueue.h> |
| |
| struct cfq_queue; |
| struct cfq_ttime { |
| unsigned long last_end_request; |
| |
| unsigned long ttime_total; |
| unsigned long ttime_samples; |
| unsigned long ttime_mean; |
| }; |
| |
| enum { |
| CIC_IOPRIO_CHANGED, |
| CIC_CGROUP_CHANGED, |
| }; |
| |
| struct cfq_io_context { |
| 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; |
| |
| unsigned long changed; |
| |
| void (*exit)(struct cfq_io_context *); |
| void (*release)(struct cfq_io_context *); |
| |
| 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; |
| |
| /* |
| * 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; |
| |
| struct work_struct release_work; |
| }; |
| |
| 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, struct request_queue *locked_q); |
| 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); |
| void ioc_ioprio_changed(struct io_context *ioc, int ioprio); |
| void ioc_cgroup_changed(struct io_context *ioc); |
| #else |
| struct io_context; |
| static inline void put_io_context(struct io_context *ioc, |
| struct request_queue *locked_q) { } |
| static inline void exit_io_context(struct task_struct *task) { } |
| #endif |
| |
| #endif |