fs/nfs/nfs4session.h

   1 /* SPDX-License-Identifier: GPL-2.0 */
   2 /*
   3  * fs/nfs/nfs4session.h
   4  *
   5  * Copyright (c) 2012 Trond Myklebust <Trond.Myklebust@netapp.com>
   6  *
   7  */
   8 #ifndef __LINUX_FS_NFS_NFS4SESSION_H
   9 #define __LINUX_FS_NFS_NFS4SESSION_H
  10
  11 /* maximum number of slots to use */
  12 #define NFS4_DEF_SLOT_TABLE_SIZE (64U)
  13 #define NFS4_DEF_CB_SLOT_TABLE_SIZE (16U)
  14 #define NFS4_MAX_SLOT_TABLE (1024U)
  15 #define NFS4_NO_SLOT ((u32)-1)
  16
  17 #if IS_ENABLED(CONFIG_NFS_V4)
  18
  19 /* Sessions slot seqid */
  20 struct nfs4_slot {
  21         struct nfs4_slot_table  *table;
  22         struct nfs4_slot        *next;
  23         unsigned long           generation;
  24         u32                     slot_nr;
  25         u32                     seq_nr;
  26         u32                     seq_nr_last_acked;
  27         u32                     seq_nr_highest_sent;
  28         unsigned int            privileged : 1,
  29                                 seq_done : 1;
  30 };
  31
  32 /* Sessions */
  33 enum nfs4_slot_tbl_state {
  34         NFS4_SLOT_TBL_DRAINING,
  35 };
  36
  37 #define SLOT_TABLE_SZ DIV_ROUND_UP(NFS4_MAX_SLOT_TABLE, BITS_PER_LONG)
  38 struct nfs4_slot_table {
  39         struct nfs4_session *session;           /* Parent session */
  40         struct nfs4_slot *slots;                /* seqid per slot */
  41         unsigned long   used_slots[SLOT_TABLE_SZ]; /* used/unused bitmap */
  42         spinlock_t      slot_tbl_lock;
  43         struct rpc_wait_queue   slot_tbl_waitq; /* allocators may wait here */
  44         wait_queue_head_t       slot_waitq;     /* Completion wait on slot */
  45         u32             max_slots;              /* # slots in table */
  46         u32             max_slotid;             /* Max allowed slotid value */
  47         u32             highest_used_slotid;    /* sent to server on each SEQ.
  48                                                  * op for dynamic resizing */
  49         u32             target_highest_slotid;  /* Server max_slot target */
  50         u32             server_highest_slotid;  /* Server highest slotid */
  51         s32             d_target_highest_slotid; /* Derivative */
  52         s32             d2_target_highest_slotid; /* 2nd derivative */
  53         unsigned long   generation;             /* Generation counter for
  54                                                    target_highest_slotid */
  55         struct completion complete;
  56         unsigned long   slot_tbl_state;
  57 };
  58
  59 /*
  60  * Session related parameters
  61  */
  62 struct nfs4_session {
  63         struct nfs4_sessionid           sess_id;
  64         u32                             flags;
  65         unsigned long                   session_state;
  66         u32                             hash_alg;
  67         u32                             ssv_len;
  68
  69         /* The fore and back channel */
  70         struct nfs4_channel_attrs       fc_attrs;
  71         struct nfs4_slot_table          fc_slot_table;
  72         struct nfs4_channel_attrs       bc_attrs;
  73         struct nfs4_slot_table          bc_slot_table;
  74         struct nfs_client               *clp;
  75 };
  76
  77 enum nfs4_session_state {
  78         NFS4_SESSION_INITING,
  79         NFS4_SESSION_ESTABLISHED,
  80 };
  81
  82 extern int nfs4_setup_slot_table(struct nfs4_slot_table *tbl,
  83                 unsigned int max_reqs, const char *queue);
  84 extern void nfs4_shutdown_slot_table(struct nfs4_slot_table *tbl);
  85 extern struct nfs4_slot *nfs4_alloc_slot(struct nfs4_slot_table *tbl);
  86 extern struct nfs4_slot *nfs4_lookup_slot(struct nfs4_slot_table *tbl, u32 slotid);
  87 extern int nfs4_slot_wait_on_seqid(struct nfs4_slot_table *tbl,
  88                 u32 slotid, u32 seq_nr,
  89                 unsigned long timeout);
  90 extern bool nfs4_try_to_lock_slot(struct nfs4_slot_table *tbl, struct nfs4_slot *slot);
  91 extern void nfs4_free_slot(struct nfs4_slot_table *tbl, struct nfs4_slot *slot);
  92 extern void nfs4_slot_tbl_drain_complete(struct nfs4_slot_table *tbl);
  93 bool nfs41_wake_and_assign_slot(struct nfs4_slot_table *tbl,
  94                 struct nfs4_slot *slot);
  95 void nfs41_wake_slot_table(struct nfs4_slot_table *tbl);
  96
  97 static inline bool nfs4_slot_tbl_draining(struct nfs4_slot_table *tbl)
  98 {
  99         return !!test_bit(NFS4_SLOT_TBL_DRAINING, &tbl->slot_tbl_state);
 100 }
 101
 102 static inline bool nfs4_test_locked_slot(const struct nfs4_slot_table *tbl,
 103                 u32 slotid)
 104 {
 105         return !!test_bit(slotid, tbl->used_slots);
 106 }
 107
 108 static inline struct nfs4_session *nfs4_get_session(const struct nfs_client *clp)
 109 {
 110         return clp->cl_session;
 111 }
 112
 113 #if defined(CONFIG_NFS_V4_1)
 114 extern void nfs41_set_target_slotid(struct nfs4_slot_table *tbl,
 115                 u32 target_highest_slotid);
 116 extern void nfs41_update_target_slotid(struct nfs4_slot_table *tbl,
 117                 struct nfs4_slot *slot,
 118                 struct nfs4_sequence_res *res);
 119
 120 extern int nfs4_setup_session_slot_tables(struct nfs4_session *ses);
 121
 122 extern struct nfs4_session *nfs4_alloc_session(struct nfs_client *clp);
 123 extern void nfs4_destroy_session(struct nfs4_session *session);
 124 extern int nfs4_init_session(struct nfs_client *clp);
 125 extern int nfs4_init_ds_session(struct nfs_client *, unsigned long);
 126
 127 /*
 128  * Determine if sessions are in use.
 129  */
 130 static inline int nfs4_has_session(const struct nfs_client *clp)
 131 {
 132         if (clp->cl_session)
 133                 return 1;
 134         return 0;
 135 }
 136
 137 static inline int nfs4_has_persistent_session(const struct nfs_client *clp)
 138 {
 139         if (nfs4_has_session(clp))
 140                 return (clp->cl_session->flags & SESSION4_PERSIST);
 141         return 0;
 142 }
 143
 144 static inline void nfs4_copy_sessionid(struct nfs4_sessionid *dst,
 145                 const struct nfs4_sessionid *src)
 146 {
 147         memcpy(dst->data, src->data, NFS4_MAX_SESSIONID_LEN);
 148 }
 149
 150 #ifdef CONFIG_CRC32
 151 /*
 152  * nfs_session_id_hash - calculate the crc32 hash for the session id
 153  * @session - pointer to session
 154  */
 155 #define nfs_session_id_hash(sess_id) \
 156         (~crc32_le(0xFFFFFFFF, &(sess_id)->data[0], sizeof((sess_id)->data)))
 157 #else
 158 #define nfs_session_id_hash(session) (0)
 159 #endif
 160 #else /* defined(CONFIG_NFS_V4_1) */
 161
 162 static inline int nfs4_init_session(struct nfs_client *clp)
 163 {
 164         return 0;
 165 }
 166
 167 /*
 168  * Determine if sessions are in use.
 169  */
 170 static inline int nfs4_has_session(const struct nfs_client *clp)
 171 {
 172         return 0;
 173 }
 174
 175 static inline int nfs4_has_persistent_session(const struct nfs_client *clp)
 176 {
 177         return 0;
 178 }
 179
 180 #define nfs_session_id_hash(session) (0)
 181
 182 #endif /* defined(CONFIG_NFS_V4_1) */
 183 #endif /* IS_ENABLED(CONFIG_NFS_V4) */
 184 #endif /* __LINUX_FS_NFS_NFS4SESSION_H */