fs/nfs/nfs4session.h

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