LXR linux/include/linux/sunrpc/sched.h

   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 */
  24struct rpc_procinfo;
  25struct 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
  32struct rpc_call_ops;
  33struct rpc_wait_queue;
  34struct 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 */
  43struct 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
  97typedef void                    (*rpc_action)(struct rpc_task *);
  98
  99struct 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
 106struct 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_MOVEABLE       0x0004          /* nfs4.1+ rpc tasks */
 125#define RPC_TASK_NULLCREDS      0x0010          /* Use AUTH_NULL credential */
 126#define RPC_CALL_MAJORSEEN      0x0020          /* major timeout seen */
 127#define RPC_TASK_ROOTCREDS      0x0040          /* force root creds */
 128#define RPC_TASK_DYNAMIC        0x0080          /* task was kmalloc'ed */
 129#define RPC_TASK_NO_ROUND_ROBIN 0x0100          /* send requests on "main" xprt */
 130#define RPC_TASK_SOFT           0x0200          /* Use soft timeouts */
 131#define RPC_TASK_SOFTCONN       0x0400          /* Fail if can't connect */
 132#define RPC_TASK_SENT           0x0800          /* message was sent */
 133#define RPC_TASK_TIMEOUT        0x1000          /* fail with ETIMEDOUT on timeout */
 134#define RPC_TASK_NOCONNECT      0x2000          /* return ENOTCONN if not connected */
 135#define RPC_TASK_NO_RETRANS_TIMEOUT     0x4000          /* wait forever for a reply */
 136#define RPC_TASK_CRED_NOREF     0x8000          /* No refcount on the credential */
 137
 138#define RPC_IS_ASYNC(t)         ((t)->tk_flags & RPC_TASK_ASYNC)
 139#define RPC_IS_SWAPPER(t)       ((t)->tk_flags & RPC_TASK_SWAPPER)
 140#define RPC_IS_SOFT(t)          ((t)->tk_flags & (RPC_TASK_SOFT|RPC_TASK_TIMEOUT))
 141#define RPC_IS_SOFTCONN(t)      ((t)->tk_flags & RPC_TASK_SOFTCONN)
 142#define RPC_WAS_SENT(t)         ((t)->tk_flags & RPC_TASK_SENT)
 143#define RPC_IS_MOVEABLE(t)      ((t)->tk_flags & RPC_TASK_MOVEABLE)
 144
 145#define RPC_TASK_RUNNING        0
 146#define RPC_TASK_QUEUED         1
 147#define RPC_TASK_ACTIVE         2
 148#define RPC_TASK_NEED_XMIT      3
 149#define RPC_TASK_NEED_RECV      4
 150#define RPC_TASK_MSG_PIN_WAIT   5
 151#define RPC_TASK_SIGNALLED      6
 152
 153#define RPC_IS_RUNNING(t)       test_bit(RPC_TASK_RUNNING, &(t)->tk_runstate)
 154#define rpc_set_running(t)      set_bit(RPC_TASK_RUNNING, &(t)->tk_runstate)
 155#define rpc_test_and_set_running(t) \
 156                                test_and_set_bit(RPC_TASK_RUNNING, &(t)->tk_runstate)
 157#define rpc_clear_running(t)    \
 158        do { \
 159                smp_mb__before_atomic(); \
 160                clear_bit(RPC_TASK_RUNNING, &(t)->tk_runstate); \
 161                smp_mb__after_atomic(); \
 162        } while (0)
 163
 164#define RPC_IS_QUEUED(t)        test_bit(RPC_TASK_QUEUED, &(t)->tk_runstate)
 165#define rpc_set_queued(t)       set_bit(RPC_TASK_QUEUED, &(t)->tk_runstate)
 166#define rpc_clear_queued(t)     \
 167        do { \
 168                smp_mb__before_atomic(); \
 169                clear_bit(RPC_TASK_QUEUED, &(t)->tk_runstate); \
 170                smp_mb__after_atomic(); \
 171        } while (0)
 172
 173#define RPC_IS_ACTIVATED(t)     test_bit(RPC_TASK_ACTIVE, &(t)->tk_runstate)
 174
 175#define RPC_SIGNALLED(t)        test_bit(RPC_TASK_SIGNALLED, &(t)->tk_runstate)
 176
 177/*
 178 * Task priorities.
 179 * Note: if you change these, you must also change
 180 * the task initialization definitions below.
 181 */
 182#define RPC_PRIORITY_LOW        (-1)
 183#define RPC_PRIORITY_NORMAL     (0)
 184#define RPC_PRIORITY_HIGH       (1)
 185#define RPC_PRIORITY_PRIVILEGED (2)
 186#define RPC_NR_PRIORITY         (1 + RPC_PRIORITY_PRIVILEGED - RPC_PRIORITY_LOW)
 187
 188struct rpc_timer {
 189        struct list_head list;
 190        unsigned long expires;
 191        struct delayed_work dwork;
 192};
 193
 194/*
 195 * RPC synchronization objects
 196 */
 197struct rpc_wait_queue {
 198        spinlock_t              lock;
 199        struct list_head        tasks[RPC_NR_PRIORITY]; /* task queue for each priority level */
 200        unsigned char           maxpriority;            /* maximum priority (0 if queue is not a priority queue) */
 201        unsigned char           priority;               /* current priority */
 202        unsigned char           nr;                     /* # tasks remaining for cookie */
 203        unsigned short          qlen;                   /* total # tasks waiting in queue */
 204        struct rpc_timer        timer_list;
 205#if IS_ENABLED(CONFIG_SUNRPC_DEBUG) || IS_ENABLED(CONFIG_TRACEPOINTS)
 206        const char *            name;
 207#endif
 208};
 209
 210/*
 211 * This is the # requests to send consecutively
 212 * from a single cookie.  The aim is to improve
 213 * performance of NFS operations such as read/write.
 214 */
 215#define RPC_IS_PRIORITY(q)              ((q)->maxpriority > 0)
 216
 217/*
 218 * Function prototypes
 219 */
 220struct rpc_task *rpc_new_task(const struct rpc_task_setup *);
 221struct rpc_task *rpc_run_task(const struct rpc_task_setup *);
 222struct rpc_task *rpc_run_bc_task(struct rpc_rqst *req);
 223void            rpc_put_task(struct rpc_task *);
 224void            rpc_put_task_async(struct rpc_task *);
 225void            rpc_signal_task(struct rpc_task *);
 226void            rpc_exit_task(struct rpc_task *);
 227void            rpc_exit(struct rpc_task *, int);
 228void            rpc_release_calldata(const struct rpc_call_ops *, void *);
 229void            rpc_killall_tasks(struct rpc_clnt *);
 230void            rpc_execute(struct rpc_task *);
 231void            rpc_init_priority_wait_queue(struct rpc_wait_queue *, const char *);
 232void            rpc_init_wait_queue(struct rpc_wait_queue *, const char *);
 233void            rpc_destroy_wait_queue(struct rpc_wait_queue *);
 234unsigned long   rpc_task_timeout(const struct rpc_task *task);
 235void            rpc_sleep_on_timeout(struct rpc_wait_queue *queue,
 236                                        struct rpc_task *task,
 237                                        rpc_action action,
 238                                        unsigned long timeout);
 239void            rpc_sleep_on(struct rpc_wait_queue *, struct rpc_task *,
 240                                        rpc_action action);
 241void            rpc_sleep_on_priority_timeout(struct rpc_wait_queue *queue,
 242                                        struct rpc_task *task,
 243                                        unsigned long timeout,
 244                                        int priority);
 245void            rpc_sleep_on_priority(struct rpc_wait_queue *,
 246                                        struct rpc_task *,
 247                                        int priority);
 248void            rpc_wake_up_queued_task(struct rpc_wait_queue *,
 249                                        struct rpc_task *);
 250void            rpc_wake_up_queued_task_set_status(struct rpc_wait_queue *,
 251                                                   struct rpc_task *,
 252                                                   int);
 253void            rpc_wake_up(struct rpc_wait_queue *);
 254struct rpc_task *rpc_wake_up_next(struct rpc_wait_queue *);
 255struct rpc_task *rpc_wake_up_first_on_wq(struct workqueue_struct *wq,
 256                                        struct rpc_wait_queue *,
 257                                        bool (*)(struct rpc_task *, void *),
 258                                        void *);
 259struct rpc_task *rpc_wake_up_first(struct rpc_wait_queue *,
 260                                        bool (*)(struct rpc_task *, void *),
 261                                        void *);
 262void            rpc_wake_up_status(struct rpc_wait_queue *, int);
 263void            rpc_delay(struct rpc_task *, unsigned long);
 264int             rpc_malloc(struct rpc_task *);
 265void            rpc_free(struct rpc_task *);
 266int             rpciod_up(void);
 267void            rpciod_down(void);
 268int             __rpc_wait_for_completion_task(struct rpc_task *task, wait_bit_action_f *);
 269#if IS_ENABLED(CONFIG_SUNRPC_DEBUG)
 270struct net;
 271void            rpc_show_tasks(struct net *);
 272#endif
 273int             rpc_init_mempool(void);
 274void            rpc_destroy_mempool(void);
 275extern struct workqueue_struct *rpciod_workqueue;
 276extern struct workqueue_struct *xprtiod_workqueue;
 277void            rpc_prepare_task(struct rpc_task *task);
 278
 279static inline int rpc_wait_for_completion_task(struct rpc_task *task)
 280{
 281        return __rpc_wait_for_completion_task(task, NULL);
 282}
 283
 284#if IS_ENABLED(CONFIG_SUNRPC_DEBUG) || IS_ENABLED(CONFIG_TRACEPOINTS)
 285static inline const char * rpc_qname(const struct rpc_wait_queue *q)
 286{
 287        return ((q && q->name) ? q->name : "unknown");
 288}
 289
 290static inline void rpc_assign_waitqueue_name(struct rpc_wait_queue *q,
 291                const char *name)
 292{
 293        q->name = name;
 294}
 295#else
 296static inline void rpc_assign_waitqueue_name(struct rpc_wait_queue *q,
 297                const char *name)
 298{
 299}
 300#endif
 301
 302#if IS_ENABLED(CONFIG_SUNRPC_SWAP)
 303int rpc_clnt_swap_activate(struct rpc_clnt *clnt);
 304void rpc_clnt_swap_deactivate(struct rpc_clnt *clnt);
 305#else
 306static inline int
 307rpc_clnt_swap_activate(struct rpc_clnt *clnt)
 308{
 309        return -EINVAL;
 310}
 311
 312static inline void
 313rpc_clnt_swap_deactivate(struct rpc_clnt *clnt)
 314{
 315}
 316#endif /* CONFIG_SUNRPC_SWAP */
 317
 318#endif /* _LINUX_SUNRPC_SCHED_H_ */
 319