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, 8*sizeof(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
nfs4_slot_tbl_draining(struct nfs4_slot_table * tbl)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
nfs4_test_locked_slot(const struct nfs4_slot_table * tbl,u32 slotid)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
nfs4_get_session(const struct nfs_client * clp)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 */
nfs4_has_session(const struct nfs_client * clp)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
nfs4_has_persistent_session(const struct nfs_client * clp)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
nfs4_copy_sessionid(struct nfs4_sessionid * dst,const struct nfs4_sessionid * src)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
nfs4_init_session(struct nfs_client * clp)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 */
nfs4_has_session(const struct nfs_client * clp)170 static inline int nfs4_has_session(const struct nfs_client *clp)
171 {
172 return 0;
173 }
174
nfs4_has_persistent_session(const struct nfs_client * clp)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 */
185
