fs/io-wq.h

   1 #ifndef INTERNAL_IO_WQ_H
   2 #define INTERNAL_IO_WQ_H
   3
   4 #include <linux/io_uring.h>
   5
   6 struct io_wq;
   7
   8 enum {
   9         IO_WQ_WORK_CANCEL       = 1,
  10         IO_WQ_WORK_HASHED       = 2,
  11         IO_WQ_WORK_UNBOUND      = 4,
  12         IO_WQ_WORK_CONCURRENT   = 16,
  13
  14         IO_WQ_WORK_FILES        = 32,
  15         IO_WQ_WORK_FS           = 64,
  16         IO_WQ_WORK_MM           = 128,
  17         IO_WQ_WORK_CREDS        = 256,
  18         IO_WQ_WORK_BLKCG        = 512,
  19         IO_WQ_WORK_FSIZE        = 1024,
  20
  21         IO_WQ_HASH_SHIFT        = 24,   /* upper 8 bits are used for hash key */
  22 };
  23
  24 enum io_wq_cancel {
  25         IO_WQ_CANCEL_OK,        /* cancelled before started */
  26         IO_WQ_CANCEL_RUNNING,   /* found, running, and attempted cancelled */
  27         IO_WQ_CANCEL_NOTFOUND,  /* work not found */
  28 };
  29
  30 struct io_wq_work_node {
  31         struct io_wq_work_node *next;
  32 };
  33
  34 struct io_wq_work_list {
  35         struct io_wq_work_node *first;
  36         struct io_wq_work_node *last;
  37 };
  38
  39 static inline void wq_list_add_after(struct io_wq_work_node *node,
  40                                      struct io_wq_work_node *pos,
  41                                      struct io_wq_work_list *list)
  42 {
  43         struct io_wq_work_node *next = pos->next;
  44
  45         pos->next = node;
  46         node->next = next;
  47         if (!next)
  48                 list->last = node;
  49 }
  50
  51 static inline void wq_list_add_tail(struct io_wq_work_node *node,
  52                                     struct io_wq_work_list *list)
  53 {
  54         if (!list->first) {
  55                 list->last = node;
  56                 WRITE_ONCE(list->first, node);
  57         } else {
  58                 list->last->next = node;
  59                 list->last = node;
  60         }
  61         node->next = NULL;
  62 }
  63
  64 static inline void wq_list_cut(struct io_wq_work_list *list,
  65                                struct io_wq_work_node *last,
  66                                struct io_wq_work_node *prev)
  67 {
  68         /* first in the list, if prev==NULL */
  69         if (!prev)
  70                 WRITE_ONCE(list->first, last->next);
  71         else
  72                 prev->next = last->next;
  73
  74         if (last == list->last)
  75                 list->last = prev;
  76         last->next = NULL;
  77 }
  78
  79 static inline void wq_list_del(struct io_wq_work_list *list,
  80                                struct io_wq_work_node *node,
  81                                struct io_wq_work_node *prev)
  82 {
  83         wq_list_cut(list, node, prev);
  84 }
  85
  86 #define wq_list_for_each(pos, prv, head)                        \
  87         for (pos = (head)->first, prv = NULL; pos; prv = pos, pos = (pos)->next)
  88
  89 #define wq_list_empty(list)     (READ_ONCE((list)->first) == NULL)
  90 #define INIT_WQ_LIST(list)      do {                            \
  91         (list)->first = NULL;                                   \
  92         (list)->last = NULL;                                    \
  93 } while (0)
  94
  95 struct io_wq_work {
  96         struct io_wq_work_node list;
  97         struct io_identity *identity;
  98         unsigned flags;
  99 };
 100
 101 static inline struct io_wq_work *wq_next_work(struct io_wq_work *work)
 102 {
 103         if (!work->list.next)
 104                 return NULL;
 105
 106         return container_of(work->list.next, struct io_wq_work, list);
 107 }
 108
 109 typedef struct io_wq_work *(free_work_fn)(struct io_wq_work *);
 110 typedef void (io_wq_work_fn)(struct io_wq_work *);
 111
 112 struct io_wq_data {
 113         struct user_struct *user;
 114
 115         io_wq_work_fn *do_work;
 116         free_work_fn *free_work;
 117 };
 118
 119 struct io_wq *io_wq_create(unsigned bounded, struct io_wq_data *data);
 120 bool io_wq_get(struct io_wq *wq, struct io_wq_data *data);
 121 void io_wq_destroy(struct io_wq *wq);
 122
 123 void io_wq_enqueue(struct io_wq *wq, struct io_wq_work *work);
 124 void io_wq_hash_work(struct io_wq_work *work, void *val);
 125
 126 static inline bool io_wq_is_hashed(struct io_wq_work *work)
 127 {
 128         return work->flags & IO_WQ_WORK_HASHED;
 129 }
 130
 131 typedef bool (work_cancel_fn)(struct io_wq_work *, void *);
 132
 133 enum io_wq_cancel io_wq_cancel_cb(struct io_wq *wq, work_cancel_fn *cancel,
 134                                         void *data, bool cancel_all);
 135
 136 struct task_struct *io_wq_get_task(struct io_wq *wq);
 137
 138 #if defined(CONFIG_IO_WQ)
 139 extern void io_wq_worker_sleeping(struct task_struct *);
 140 extern void io_wq_worker_running(struct task_struct *);
 141 #else
 142 static inline void io_wq_worker_sleeping(struct task_struct *tsk)
 143 {
 144 }
 145 static inline void io_wq_worker_running(struct task_struct *tsk)
 146 {
 147 }
 148 #endif
 149
 150 static inline bool io_wq_current_is_worker(void)
 151 {
 152         return in_task() && (current->flags & PF_IO_WORKER);
 153 }
 154 #endif