blob: 351616c61df541fcb9e09e1df7d1ebbc0f8883d2 [file] [log] [blame]
/* SPDX-License-Identifier: GPL-2.0 */
* fs/nfs/nfs4session.h
* Copyright (c) 2012 Trond Myklebust <>
/* maximum number of slots to use */
#define NFS4_MAX_SLOT_TABLE (1024U)
#define NFS4_NO_SLOT ((u32)-1)
/* Sessions slot seqid */
struct nfs4_slot {
struct nfs4_slot_table *table;
struct nfs4_slot *next;
unsigned long generation;
u32 slot_nr;
u32 seq_nr;
u32 seq_nr_last_acked;
u32 seq_nr_highest_sent;
unsigned int privileged : 1,
seq_done : 1;
/* Sessions */
enum nfs4_slot_tbl_state {
struct nfs4_slot_table {
struct nfs4_session *session; /* Parent session */
struct nfs4_slot *slots; /* seqid per slot */
unsigned long used_slots[SLOT_TABLE_SZ]; /* used/unused bitmap */
spinlock_t slot_tbl_lock;
struct rpc_wait_queue slot_tbl_waitq; /* allocators may wait here */
wait_queue_head_t slot_waitq; /* Completion wait on slot */
u32 max_slots; /* # slots in table */
u32 max_slotid; /* Max allowed slotid value */
u32 highest_used_slotid; /* sent to server on each SEQ.
* op for dynamic resizing */
u32 target_highest_slotid; /* Server max_slot target */
u32 server_highest_slotid; /* Server highest slotid */
s32 d_target_highest_slotid; /* Derivative */
s32 d2_target_highest_slotid; /* 2nd derivative */
unsigned long generation; /* Generation counter for
target_highest_slotid */
struct completion complete;
unsigned long slot_tbl_state;
* Session related parameters
struct nfs4_session {
struct nfs4_sessionid sess_id;
u32 flags;
unsigned long session_state;
u32 hash_alg;
u32 ssv_len;
/* The fore and back channel */
struct nfs4_channel_attrs fc_attrs;
struct nfs4_slot_table fc_slot_table;
struct nfs4_channel_attrs bc_attrs;
struct nfs4_slot_table bc_slot_table;
struct nfs_client *clp;
enum nfs4_session_state {
extern int nfs4_setup_slot_table(struct nfs4_slot_table *tbl,
unsigned int max_reqs, const char *queue);
extern void nfs4_shutdown_slot_table(struct nfs4_slot_table *tbl);
extern struct nfs4_slot *nfs4_alloc_slot(struct nfs4_slot_table *tbl);
extern struct nfs4_slot *nfs4_lookup_slot(struct nfs4_slot_table *tbl, u32 slotid);
extern int nfs4_slot_wait_on_seqid(struct nfs4_slot_table *tbl,
u32 slotid, u32 seq_nr,
unsigned long timeout);
extern bool nfs4_try_to_lock_slot(struct nfs4_slot_table *tbl, struct nfs4_slot *slot);
extern void nfs4_free_slot(struct nfs4_slot_table *tbl, struct nfs4_slot *slot);
extern void nfs4_slot_tbl_drain_complete(struct nfs4_slot_table *tbl);
bool nfs41_wake_and_assign_slot(struct nfs4_slot_table *tbl,
struct nfs4_slot *slot);
void nfs41_wake_slot_table(struct nfs4_slot_table *tbl);
static inline bool nfs4_slot_tbl_draining(struct nfs4_slot_table *tbl)
return !!test_bit(NFS4_SLOT_TBL_DRAINING, &tbl->slot_tbl_state);
static inline bool nfs4_test_locked_slot(const struct nfs4_slot_table *tbl,
u32 slotid)
return !!test_bit(slotid, tbl->used_slots);
static inline struct nfs4_session *nfs4_get_session(const struct nfs_client *clp)
return clp->cl_session;
#if defined(CONFIG_NFS_V4_1)
extern void nfs41_set_target_slotid(struct nfs4_slot_table *tbl,
u32 target_highest_slotid);
extern void nfs41_update_target_slotid(struct nfs4_slot_table *tbl,
struct nfs4_slot *slot,
struct nfs4_sequence_res *res);
extern int nfs4_setup_session_slot_tables(struct nfs4_session *ses);
extern struct nfs4_session *nfs4_alloc_session(struct nfs_client *clp);
extern void nfs4_destroy_session(struct nfs4_session *session);
extern int nfs4_init_session(struct nfs_client *clp);
extern int nfs4_init_ds_session(struct nfs_client *, unsigned long);
* Determine if sessions are in use.
static inline int nfs4_has_session(const struct nfs_client *clp)
if (clp->cl_session)
return 1;
return 0;
static inline int nfs4_has_persistent_session(const struct nfs_client *clp)
if (nfs4_has_session(clp))
return (clp->cl_session->flags & SESSION4_PERSIST);
return 0;
static inline void nfs4_copy_sessionid(struct nfs4_sessionid *dst,
const struct nfs4_sessionid *src)
memcpy(dst->data, src->data, NFS4_MAX_SESSIONID_LEN);
#ifdef CONFIG_CRC32
* nfs_session_id_hash - calculate the crc32 hash for the session id
* @session - pointer to session
#define nfs_session_id_hash(sess_id) \
(~crc32_le(0xFFFFFFFF, &(sess_id)->data[0], sizeof((sess_id)->data)))
#define nfs_session_id_hash(session) (0)
#else /* defined(CONFIG_NFS_V4_1) */
static inline int nfs4_init_session(struct nfs_client *clp)
return 0;
* Determine if sessions are in use.
static inline int nfs4_has_session(const struct nfs_client *clp)
return 0;
static inline int nfs4_has_persistent_session(const struct nfs_client *clp)
return 0;
#define nfs_session_id_hash(session) (0)
#endif /* defined(CONFIG_NFS_V4_1) */
#endif /* IS_ENABLED(CONFIG_NFS_V4) */