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
nfs4_slot_tbl_draining(struct nfs4_slot_table * tbl)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
nfs4_test_locked_slot(const struct nfs4_slot_table * tbl,u32 slotid)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
nfs4_get_session(const struct nfs_client * clp)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 */
nfs4_has_session(const struct nfs_client * clp)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
nfs4_has_persistent_session(const struct nfs_client * clp)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
nfs4_copy_sessionid(struct nfs4_sessionid * dst,const struct nfs4_sessionid * src)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
nfs4_init_session(struct nfs_client * clp)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 */
nfs4_has_session(const struct nfs_client * clp)169 static inline int nfs4_has_session(const struct nfs_client *clp)
170 {
171 return 0;
172 }
173
nfs4_has_persistent_session(const struct nfs_client * clp)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 */
184