root/include/linux/sunrpc/sched.h

INCLUDED FROM

DEFINITIONS

1. rpc_wait_for_completion_task
2. rpc_qname
3. rpc_assign_waitqueue_name
4. rpc_assign_waitqueue_name
5. rpc_clnt_swap_activate
6. rpc_clnt_swap_deactivate

   1 /* SPDX-License-Identifier: GPL-2.0 */
   2 /*
   3  * linux/include/linux/sunrpc/sched.h
   4  *
   5  * Scheduling primitives for kernel Sun RPC.
   6  *
   7  * Copyright (C) 1996, Olaf Kirch <okir@monad.swb.de>
   8  */
   9 
  10 #ifndef _LINUX_SUNRPC_SCHED_H_
  11 #define _LINUX_SUNRPC_SCHED_H_
  12 
  13 #include <linux/timer.h>
  14 #include <linux/ktime.h>
  15 #include <linux/sunrpc/types.h>
  16 #include <linux/spinlock.h>
  17 #include <linux/wait_bit.h>
  18 #include <linux/workqueue.h>
  19 #include <linux/sunrpc/xdr.h>
  20 
  21 /*
  22  * This is the actual RPC procedure call info.
  23  */
  24 struct rpc_procinfo;
  25 struct rpc_message {
  26         const struct rpc_procinfo *rpc_proc;    /* Procedure information */
  27         void *                  rpc_argp;       /* Arguments */
  28         void *                  rpc_resp;       /* Result */
  29         const struct cred *     rpc_cred;       /* Credentials */
  30 };
  31 
  32 struct rpc_call_ops;
  33 struct rpc_wait_queue;
  34 struct rpc_wait {
  35         struct list_head        list;           /* wait queue links */
  36         struct list_head        links;          /* Links to related tasks */
  37         struct list_head        timer_list;     /* Timer list */
  38 };
  39 
  40 /*
  41  * This is the RPC task struct
  42  */
  43 struct rpc_task {
  44         atomic_t                tk_count;       /* Reference count */
  45         int                     tk_status;      /* result of last operation */
  46         struct list_head        tk_task;        /* global list of tasks */
  47 
  48         /*
  49          * callback     to be executed after waking up
  50          * action       next procedure for async tasks
  51          */
  52         void                    (*tk_callback)(struct rpc_task *);
  53         void                    (*tk_action)(struct rpc_task *);
  54 
  55         unsigned long           tk_timeout;     /* timeout for rpc_sleep() */
  56         unsigned long           tk_runstate;    /* Task run status */
  57 
  58         struct rpc_wait_queue   *tk_waitqueue;  /* RPC wait queue we're on */
  59         union {
  60                 struct work_struct      tk_work;        /* Async task work queue */
  61                 struct rpc_wait         tk_wait;        /* RPC wait */
  62         } u;
  63 
  64         int                     tk_rpc_status;  /* Result of last RPC operation */
  65 
  66         /*
  67          * RPC call state
  68          */
  69         struct rpc_message      tk_msg;         /* RPC call info */
  70         void *                  tk_calldata;    /* Caller private data */
  71         const struct rpc_call_ops *tk_ops;      /* Caller callbacks */
  72 
  73         struct rpc_clnt *       tk_client;      /* RPC client */
  74         struct rpc_xprt *       tk_xprt;        /* Transport */
  75         struct rpc_cred *       tk_op_cred;     /* cred being operated on */
  76 
  77         struct rpc_rqst *       tk_rqstp;       /* RPC request */
  78 
  79         struct workqueue_struct *tk_workqueue;  /* Normally rpciod, but could
  80                                                  * be any workqueue
  81                                                  */
  82         ktime_t                 tk_start;       /* RPC task init timestamp */
  83 
  84         pid_t                   tk_owner;       /* Process id for batching tasks */
  85         unsigned short          tk_flags;       /* misc flags */
  86         unsigned short          tk_timeouts;    /* maj timeouts */
  87 
  88 #if IS_ENABLED(CONFIG_SUNRPC_DEBUG) || IS_ENABLED(CONFIG_TRACEPOINTS)
  89         unsigned short          tk_pid;         /* debugging aid */
  90 #endif
  91         unsigned char           tk_priority : 2,/* Task priority */
  92                                 tk_garb_retry : 2,
  93                                 tk_cred_retry : 2,
  94                                 tk_rebind_retry : 2;
  95 };
  96 
  97 typedef void                    (*rpc_action)(struct rpc_task *);
  98 
  99 struct rpc_call_ops {
 100         void (*rpc_call_prepare)(struct rpc_task *, void *);
 101         void (*rpc_call_done)(struct rpc_task *, void *);
 102         void (*rpc_count_stats)(struct rpc_task *, void *);
 103         void (*rpc_release)(void *);
 104 };
 105 
 106 struct rpc_task_setup {
 107         struct rpc_task *task;
 108         struct rpc_clnt *rpc_client;
 109         struct rpc_xprt *rpc_xprt;
 110         struct rpc_cred *rpc_op_cred;   /* credential being operated on */
 111         const struct rpc_message *rpc_message;
 112         const struct rpc_call_ops *callback_ops;
 113         void *callback_data;
 114         struct workqueue_struct *workqueue;
 115         unsigned short flags;
 116         signed char priority;
 117 };
 118 
 119 /*
 120  * RPC task flags
 121  */
 122 #define RPC_TASK_ASYNC          0x0001          /* is an async task */
 123 #define RPC_TASK_SWAPPER        0x0002          /* is swapping in/out */
 124 #define RPC_TASK_NULLCREDS      0x0010          /* Use AUTH_NULL credential */
 125 #define RPC_CALL_MAJORSEEN      0x0020          /* major timeout seen */
 126 #define RPC_TASK_ROOTCREDS      0x0040          /* force root creds */
 127 #define RPC_TASK_DYNAMIC        0x0080          /* task was kmalloc'ed */
 128 #define RPC_TASK_NO_ROUND_ROBIN 0x0100          /* send requests on "main" xprt */
 129 #define RPC_TASK_SOFT           0x0200          /* Use soft timeouts */
 130 #define RPC_TASK_SOFTCONN       0x0400          /* Fail if can't connect */
 131 #define RPC_TASK_SENT           0x0800          /* message was sent */
 132 #define RPC_TASK_TIMEOUT        0x1000          /* fail with ETIMEDOUT on timeout */
 133 #define RPC_TASK_NOCONNECT      0x2000          /* return ENOTCONN if not connected */
 134 #define RPC_TASK_NO_RETRANS_TIMEOUT     0x4000          /* wait forever for a reply */
 135 
 136 #define RPC_IS_ASYNC(t)         ((t)->tk_flags & RPC_TASK_ASYNC)
 137 #define RPC_IS_SWAPPER(t)       ((t)->tk_flags & RPC_TASK_SWAPPER)
 138 #define RPC_IS_SOFT(t)          ((t)->tk_flags & (RPC_TASK_SOFT|RPC_TASK_TIMEOUT))
 139 #define RPC_IS_SOFTCONN(t)      ((t)->tk_flags & RPC_TASK_SOFTCONN)
 140 #define RPC_WAS_SENT(t)         ((t)->tk_flags & RPC_TASK_SENT)
 141 
 142 #define RPC_TASK_RUNNING        0
 143 #define RPC_TASK_QUEUED         1
 144 #define RPC_TASK_ACTIVE         2
 145 #define RPC_TASK_NEED_XMIT      3
 146 #define RPC_TASK_NEED_RECV      4
 147 #define RPC_TASK_MSG_PIN_WAIT   5
 148 #define RPC_TASK_SIGNALLED      6
 149 
 150 #define RPC_IS_RUNNING(t)       test_bit(RPC_TASK_RUNNING, &(t)->tk_runstate)
 151 #define rpc_set_running(t)      set_bit(RPC_TASK_RUNNING, &(t)->tk_runstate)
 152 #define rpc_test_and_set_running(t) \
 153                                 test_and_set_bit(RPC_TASK_RUNNING, &(t)->tk_runstate)
 154 #define rpc_clear_running(t)    \
 155         do { \
 156                 smp_mb__before_atomic(); \
 157                 clear_bit(RPC_TASK_RUNNING, &(t)->tk_runstate); \
 158                 smp_mb__after_atomic(); \
 159         } while (0)
 160 
 161 #define RPC_IS_QUEUED(t)        test_bit(RPC_TASK_QUEUED, &(t)->tk_runstate)
 162 #define rpc_set_queued(t)       set_bit(RPC_TASK_QUEUED, &(t)->tk_runstate)
 163 #define rpc_clear_queued(t)     \
 164         do { \
 165                 smp_mb__before_atomic(); \
 166                 clear_bit(RPC_TASK_QUEUED, &(t)->tk_runstate); \
 167                 smp_mb__after_atomic(); \
 168         } while (0)
 169 
 170 #define RPC_IS_ACTIVATED(t)     test_bit(RPC_TASK_ACTIVE, &(t)->tk_runstate)
 171 
 172 #define RPC_SIGNALLED(t)        test_bit(RPC_TASK_SIGNALLED, &(t)->tk_runstate)
 173 
 174 /*
 175  * Task priorities.
 176  * Note: if you change these, you must also change
 177  * the task initialization definitions below.
 178  */
 179 #define RPC_PRIORITY_LOW        (-1)
 180 #define RPC_PRIORITY_NORMAL     (0)
 181 #define RPC_PRIORITY_HIGH       (1)
 182 #define RPC_PRIORITY_PRIVILEGED (2)
 183 #define RPC_NR_PRIORITY         (1 + RPC_PRIORITY_PRIVILEGED - RPC_PRIORITY_LOW)
 184 
 185 struct rpc_timer {
 186         struct list_head list;
 187         unsigned long expires;
 188         struct delayed_work dwork;
 189 };
 190 
 191 /*
 192  * RPC synchronization objects
 193  */
 194 struct rpc_wait_queue {
 195         spinlock_t              lock;
 196         struct list_head        tasks[RPC_NR_PRIORITY]; /* task queue for each priority level */
 197         unsigned char           maxpriority;            /* maximum priority (0 if queue is not a priority queue) */
 198         unsigned char           priority;               /* current priority */
 199         unsigned char           nr;                     /* # tasks remaining for cookie */
 200         unsigned short          qlen;                   /* total # tasks waiting in queue */
 201         struct rpc_timer        timer_list;
 202 #if IS_ENABLED(CONFIG_SUNRPC_DEBUG) || IS_ENABLED(CONFIG_TRACEPOINTS)
 203         const char *            name;
 204 #endif
 205 };
 206 
 207 /*
 208  * This is the # requests to send consecutively
 209  * from a single cookie.  The aim is to improve
 210  * performance of NFS operations such as read/write.
 211  */
 212 #define RPC_IS_PRIORITY(q)              ((q)->maxpriority > 0)
 213 
 214 /*
 215  * Function prototypes
 216  */
 217 struct rpc_task *rpc_new_task(const struct rpc_task_setup *);
 218 struct rpc_task *rpc_run_task(const struct rpc_task_setup *);
 219 struct rpc_task *rpc_run_bc_task(struct rpc_rqst *req);
 220 void            rpc_put_task(struct rpc_task *);
 221 void            rpc_put_task_async(struct rpc_task *);
 222 void            rpc_signal_task(struct rpc_task *);
 223 void            rpc_exit_task(struct rpc_task *);
 224 void            rpc_exit(struct rpc_task *, int);
 225 void            rpc_release_calldata(const struct rpc_call_ops *, void *);
 226 void            rpc_killall_tasks(struct rpc_clnt *);
 227 void            rpc_execute(struct rpc_task *);
 228 void            rpc_init_priority_wait_queue(struct rpc_wait_queue *, const char *);
 229 void            rpc_init_wait_queue(struct rpc_wait_queue *, const char *);
 230 void            rpc_destroy_wait_queue(struct rpc_wait_queue *);
 231 unsigned long   rpc_task_timeout(const struct rpc_task *task);
 232 void            rpc_sleep_on_timeout(struct rpc_wait_queue *queue,
 233                                         struct rpc_task *task,
 234                                         rpc_action action,
 235                                         unsigned long timeout);
 236 void            rpc_sleep_on(struct rpc_wait_queue *, struct rpc_task *,
 237                                         rpc_action action);
 238 void            rpc_sleep_on_priority_timeout(struct rpc_wait_queue *queue,
 239                                         struct rpc_task *task,
 240                                         unsigned long timeout,
 241                                         int priority);
 242 void            rpc_sleep_on_priority(struct rpc_wait_queue *,
 243                                         struct rpc_task *,
 244                                         int priority);
 245 void            rpc_wake_up_queued_task(struct rpc_wait_queue *,
 246                                         struct rpc_task *);
 247 void            rpc_wake_up_queued_task_set_status(struct rpc_wait_queue *,
 248                                                    struct rpc_task *,
 249                                                    int);
 250 void            rpc_wake_up(struct rpc_wait_queue *);
 251 struct rpc_task *rpc_wake_up_next(struct rpc_wait_queue *);
 252 struct rpc_task *rpc_wake_up_first_on_wq(struct workqueue_struct *wq,
 253                                         struct rpc_wait_queue *,
 254                                         bool (*)(struct rpc_task *, void *),
 255                                         void *);
 256 struct rpc_task *rpc_wake_up_first(struct rpc_wait_queue *,
 257                                         bool (*)(struct rpc_task *, void *),
 258                                         void *);
 259 void            rpc_wake_up_status(struct rpc_wait_queue *, int);
 260 void            rpc_delay(struct rpc_task *, unsigned long);
 261 int             rpc_malloc(struct rpc_task *);
 262 void            rpc_free(struct rpc_task *);
 263 int             rpciod_up(void);
 264 void            rpciod_down(void);
 265 int             __rpc_wait_for_completion_task(struct rpc_task *task, wait_bit_action_f *);
 266 #if IS_ENABLED(CONFIG_SUNRPC_DEBUG)
 267 struct net;
 268 void            rpc_show_tasks(struct net *);
 269 #endif
 270 int             rpc_init_mempool(void);
 271 void            rpc_destroy_mempool(void);
 272 extern struct workqueue_struct *rpciod_workqueue;
 273 extern struct workqueue_struct *xprtiod_workqueue;
 274 void            rpc_prepare_task(struct rpc_task *task);
 275 
 276 static inline int rpc_wait_for_completion_task(struct rpc_task *task)
 277 {
 278         return __rpc_wait_for_completion_task(task, NULL);
 279 }
 280 
 281 #if IS_ENABLED(CONFIG_SUNRPC_DEBUG) || IS_ENABLED(CONFIG_TRACEPOINTS)
 282 static inline const char * rpc_qname(const struct rpc_wait_queue *q)
 283 {
 284         return ((q && q->name) ? q->name : "unknown");
 285 }
 286 
 287 static inline void rpc_assign_waitqueue_name(struct rpc_wait_queue *q,
 288                 const char *name)
 289 {
 290         q->name = name;
 291 }
 292 #else
 293 static inline void rpc_assign_waitqueue_name(struct rpc_wait_queue *q,
 294                 const char *name)
 295 {
 296 }
 297 #endif
 298 
 299 #if IS_ENABLED(CONFIG_SUNRPC_SWAP)
 300 int rpc_clnt_swap_activate(struct rpc_clnt *clnt);
 301 void rpc_clnt_swap_deactivate(struct rpc_clnt *clnt);
 302 #else
 303 static inline int
 304 rpc_clnt_swap_activate(struct rpc_clnt *clnt)
 305 {
 306         return -EINVAL;
 307 }
 308 
 309 static inline void
 310 rpc_clnt_swap_deactivate(struct rpc_clnt *clnt)
 311 {
 312 }
 313 #endif /* CONFIG_SUNRPC_SWAP */
 314 
 315 #endif /* _LINUX_SUNRPC_SCHED_H_ */