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