[linux-2.6-block.git] / fs / nfs / nfs4session.h

/*
 * fs/nfs/nfs4session.h
 *
 * Copyright (c) 2012 Trond Myklebust <Trond.Myklebust@netapp.com>
 *
 */
#ifndef __LINUX_FS_NFS_NFS4SESSION_H
#define __LINUX_FS_NFS_NFS4SESSION_H

/* maximum number of slots to use */
#define NFS4_DEF_SLOT_TABLE_SIZE (64U)
#define NFS4_MAX_SLOT_TABLE (1024U)
#define NFS4_NO_SLOT ((u32)-1)

#if IS_ENABLED(CONFIG_NFS_V4)

/* Sessions slot seqid */
struct nfs4_slot {
	struct nfs4_slot_table	*table;
	struct nfs4_slot	*next;
	unsigned long		generation;
	u32			slot_nr;
	u32		 	seq_nr;
	unsigned int		interrupted : 1;
};

/* Sessions */
enum nfs4_slot_tbl_state {
	NFS4_SLOT_TBL_DRAINING,
};

#define SLOT_TABLE_SZ DIV_ROUND_UP(NFS4_MAX_SLOT_TABLE, 8*sizeof(long))
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 */
	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 {
	NFS4_SESSION_INITING,
	NFS4_SESSION_ESTABLISHED,
};

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 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);
}

#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)))
#else
#define nfs_session_id_hash(session) (0)
#endif
#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;
}

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