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_MAX_SLOTID (NFS4_MAX_SLOT_TABLE - 1U) 16 #define NFS4_NO_SLOT ((u32)-1) 17 18 #if IS_ENABLED(CONFIG_NFS_V4) 19 20 /* Sessions slot seqid */ 21 struct nfs4_slot { 22 struct nfs4_slot_table *table; 23 struct nfs4_slot *next; 24 unsigned long generation; 25 u32 slot_nr; 26 u32 seq_nr; 27 u32 seq_nr_last_acked; 28 u32 seq_nr_highest_sent; 29 unsigned int privileged : 1, 30 seq_done : 1; 31 }; 32 33 /* Sessions */ 34 enum nfs4_slot_tbl_state { 35 NFS4_SLOT_TBL_DRAINING, 36 }; 37 38 #define SLOT_TABLE_SZ DIV_ROUND_UP(NFS4_MAX_SLOT_TABLE, BITS_PER_LONG) 39 struct nfs4_slot_table { 40 struct nfs4_session *session; /* Parent session */ 41 struct nfs4_slot *slots; /* seqid per slot */ 42 unsigned long used_slots[SLOT_TABLE_SZ]; /* used/unused bitmap */ 43 spinlock_t slot_tbl_lock; 44 struct rpc_wait_queue slot_tbl_waitq; /* allocators may wait here */ 45 wait_queue_head_t slot_waitq; /* Completion wait on slot */ 46 u32 max_slots; /* # slots in table */ 47 u32 max_slotid; /* Max allowed slotid value */ 48 u32 highest_used_slotid; /* sent to server on each SEQ. 49 * op for dynamic resizing */ 50 u32 target_highest_slotid; /* Server max_slot target */ 51 u32 server_highest_slotid; /* Server highest slotid */ 52 s32 d_target_highest_slotid; /* Derivative */ 53 s32 d2_target_highest_slotid; /* 2nd derivative */ 54 unsigned long generation; /* Generation counter for 55 target_highest_slotid */ 56 struct completion complete; 57 unsigned long slot_tbl_state; 58 }; 59 60 /* 61 * Session related parameters 62 */ 63 struct nfs4_session { 64 struct nfs4_sessionid sess_id; 65 u32 flags; 66 unsigned long session_state; 67 u32 hash_alg; 68 u32 ssv_len; 69 70 /* The fore and back channel */ 71 struct nfs4_channel_attrs fc_attrs; 72 struct nfs4_slot_table fc_slot_table; 73 struct nfs4_channel_attrs bc_attrs; 74 struct nfs4_slot_table bc_slot_table; 75 struct nfs_client *clp; 76 }; 77 78 enum nfs4_session_state { 79 NFS4_SESSION_INITING, 80 NFS4_SESSION_ESTABLISHED, 81 }; 82 83 extern int nfs4_setup_slot_table(struct nfs4_slot_table *tbl, 84 unsigned int max_reqs, const char *queue); 85 extern void nfs4_shutdown_slot_table(struct nfs4_slot_table *tbl); 86 extern struct nfs4_slot *nfs4_alloc_slot(struct nfs4_slot_table *tbl); 87 extern struct nfs4_slot *nfs4_lookup_slot(struct nfs4_slot_table *tbl, u32 slotid); 88 extern int nfs4_slot_wait_on_seqid(struct nfs4_slot_table *tbl, 89 u32 slotid, u32 seq_nr, 90 unsigned long timeout); 91 extern bool nfs4_try_to_lock_slot(struct nfs4_slot_table *tbl, struct nfs4_slot *slot); 92 extern void nfs4_free_slot(struct nfs4_slot_table *tbl, struct nfs4_slot *slot); 93 extern void nfs4_slot_tbl_drain_complete(struct nfs4_slot_table *tbl); 94 bool nfs41_wake_and_assign_slot(struct nfs4_slot_table *tbl, 95 struct nfs4_slot *slot); 96 void nfs41_wake_slot_table(struct nfs4_slot_table *tbl); 97 98 static inline bool nfs4_slot_tbl_draining(struct nfs4_slot_table *tbl) 99 { 100 return !!test_bit(NFS4_SLOT_TBL_DRAINING, &tbl->slot_tbl_state); 101 } 102 103 static inline bool nfs4_test_locked_slot(const struct nfs4_slot_table *tbl, 104 u32 slotid) 105 { 106 return !!test_bit(slotid, tbl->used_slots); 107 } 108 109 static inline struct nfs4_session *nfs4_get_session(const struct nfs_client *clp) 110 { 111 return clp->cl_session; 112 } 113 114 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 /* 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))) 156 157 #endif /* IS_ENABLED(CONFIG_NFS_V4) */ 158 #endif /* __LINUX_FS_NFS_NFS4SESSION_H */ 159