fs/nfs/nfs4session.h

Source file repositories/reference/linux-study-clean/fs/nfs/nfs4session.h

File Facts

System
Linux kernel
Corpus path
fs/nfs/nfs4session.h
Extension
.h
Size
4853 bytes
Lines
159
Domain
Core OS
Bucket
VFS And Filesystem Core
Inferred role
Core OS: implementation source
Status
source implementation candidate

Why This File Exists

Core operating-system implementation surface: boot, tasks, memory, VFS, syscall-facing interfaces, synchronization, credentials, and isolation.

Dependency Surface

Detected Declarations

Annotated Snippet

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 {
	NFS4_SLOT_TBL_DRAINING,
};

#define SLOT_TABLE_SZ DIV_ROUND_UP(NFS4_MAX_SLOT_TABLE, BITS_PER_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 */
	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 {
	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 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)
{

Annotation

Implementation Notes