Adding upstream version 6.1.76.upstream/6.1.76

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 734 insertions, 0 deletions

diff --git a/fs/nfsd/state.h b/fs/nfsd/state.h
new file mode 100644
index 000000000..e2daef3cc
--- /dev/null
+++ b/fs/nfsd/state.h
@@ -0,0 +1,734 @@
+/*
+ *  Copyright (c) 2001 The Regents of the University of Michigan.
+ *  All rights reserved.
+ *
+ *  Kendrick Smith <kmsmith@umich.edu>
+ *  Andy Adamson <andros@umich.edu>
+ *  
+ *  Redistribution and use in source and binary forms, with or without
+ *  modification, are permitted provided that the following conditions
+ *  are met:
+ *  
+ *  1. Redistributions of source code must retain the above copyright
+ *     notice, this list of conditions and the following disclaimer.
+ *  2. Redistributions in binary form must reproduce the above copyright
+ *     notice, this list of conditions and the following disclaimer in the
+ *     documentation and/or other materials provided with the distribution.
+ *  3. Neither the name of the University nor the names of its
+ *     contributors may be used to endorse or promote products derived
+ *     from this software without specific prior written permission.
+ *
+ *  THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESS OR IMPLIED
+ *  WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
+ *  MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+ *  DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
+ *  FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
+ *  CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
+ *  SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR
+ *  BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
+ *  LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
+ *  NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
+ *  SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ *
+ */
+
+#ifndef _NFSD4_STATE_H
+#define _NFSD4_STATE_H
+
+#include <linux/idr.h>
+#include <linux/refcount.h>
+#include <linux/sunrpc/svc_xprt.h>
+#include "nfsfh.h"
+#include "nfsd.h"
+
+typedef struct {
+	u32             cl_boot;
+	u32             cl_id;
+} clientid_t;
+
+typedef struct {
+	clientid_t	so_clid;
+	u32		so_id;
+} stateid_opaque_t;
+
+typedef struct {
+	u32                     si_generation;
+	stateid_opaque_t        si_opaque;
+} stateid_t;
+
+typedef struct {
+	stateid_t		cs_stid;
+#define NFS4_COPY_STID 1
+#define NFS4_COPYNOTIFY_STID 2
+	unsigned char		cs_type;
+	refcount_t		cs_count;
+} copy_stateid_t;
+
+struct nfsd4_callback {
+	struct nfs4_client *cb_clp;
+	struct rpc_message cb_msg;
+	const struct nfsd4_callback_ops *cb_ops;
+	struct work_struct cb_work;
+	int cb_seq_status;
+	int cb_status;
+	bool cb_need_restart;
+	bool cb_holds_slot;
+};
+
+struct nfsd4_callback_ops {
+	void (*prepare)(struct nfsd4_callback *);
+	int (*done)(struct nfsd4_callback *, struct rpc_task *);
+	void (*release)(struct nfsd4_callback *);
+};
+
+/*
+ * A core object that represents a "common" stateid. These are generally
+ * embedded within the different (more specific) stateid objects and contain
+ * fields that are of general use to any stateid.
+ */
+struct nfs4_stid {
+	refcount_t		sc_count;
+#define NFS4_OPEN_STID 1
+#define NFS4_LOCK_STID 2
+#define NFS4_DELEG_STID 4
+/* For an open stateid kept around *only* to process close replays: */
+#define NFS4_CLOSED_STID 8
+/* For a deleg stateid kept around only to process free_stateid's: */
+#define NFS4_REVOKED_DELEG_STID 16
+#define NFS4_CLOSED_DELEG_STID 32
+#define NFS4_LAYOUT_STID 64
+	struct list_head	sc_cp_list;
+	unsigned char		sc_type;
+	stateid_t		sc_stateid;
+	spinlock_t		sc_lock;
+	struct nfs4_client	*sc_client;
+	struct nfs4_file	*sc_file;
+	void			(*sc_free)(struct nfs4_stid *);
+};
+
+/* Keep a list of stateids issued by the COPY_NOTIFY, associate it with the
+ * parent OPEN/LOCK/DELEG stateid.
+ */
+struct nfs4_cpntf_state {
+	copy_stateid_t		cp_stateid;
+	struct list_head	cp_list;	/* per parent nfs4_stid */
+	stateid_t		cp_p_stateid;	/* copy of parent's stateid */
+	clientid_t		cp_p_clid;	/* copy of parent's clid */
+	time64_t		cpntf_time;	/* last time stateid used */
+};
+
+/*
+ * Represents a delegation stateid. The nfs4_client holds references to these
+ * and they are put when it is being destroyed or when the delegation is
+ * returned by the client:
+ *
+ * o 1 reference as long as a delegation is still in force (taken when it's
+ *   alloc'd, put when it's returned or revoked)
+ *
+ * o 1 reference as long as a recall rpc is in progress (taken when the lease
+ *   is broken, put when the rpc exits)
+ *
+ * o 1 more ephemeral reference for each nfsd thread currently doing something
+ *   with that delegation without holding the cl_lock
+ *
+ * If the server attempts to recall a delegation and the client doesn't do so
+ * before a timeout, the server may also revoke the delegation. In that case,
+ * the object will either be destroyed (v4.0) or moved to a per-client list of
+ * revoked delegations (v4.1+).
+ *
+ * This object is a superset of the nfs4_stid.
+ */
+struct nfs4_delegation {
+	struct nfs4_stid	dl_stid; /* must be first field */
+	struct list_head	dl_perfile;
+	struct list_head	dl_perclnt;
+	struct list_head	dl_recall_lru;  /* delegation recalled */
+	struct nfs4_clnt_odstate *dl_clnt_odstate;
+	u32			dl_type;
+	time64_t		dl_time;
+/* For recall: */
+	int			dl_retries;
+	struct nfsd4_callback	dl_recall;
+	bool			dl_recalled;
+};
+
+#define cb_to_delegation(cb) \
+	container_of(cb, struct nfs4_delegation, dl_recall)
+
+/* client delegation callback info */
+struct nfs4_cb_conn {
+	/* SETCLIENTID info */
+	struct sockaddr_storage	cb_addr;
+	struct sockaddr_storage	cb_saddr;
+	size_t			cb_addrlen;
+	u32                     cb_prog; /* used only in 4.0 case;
+					    per-session otherwise */
+	u32                     cb_ident;	/* minorversion 0 only */
+	struct svc_xprt		*cb_xprt;	/* minorversion 1 only */
+};
+
+static inline struct nfs4_delegation *delegstateid(struct nfs4_stid *s)
+{
+	return container_of(s, struct nfs4_delegation, dl_stid);
+}
+
+/* Maximum number of slots per session. 160 is useful for long haul TCP */
+#define NFSD_MAX_SLOTS_PER_SESSION     160
+/* Maximum number of operations per session compound */
+#define NFSD_MAX_OPS_PER_COMPOUND	50
+/* Maximum  session per slot cache size */
+#define NFSD_SLOT_CACHE_SIZE		2048
+/* Maximum number of NFSD_SLOT_CACHE_SIZE slots per session */
+#define NFSD_CACHE_SIZE_SLOTS_PER_SESSION	32
+#define NFSD_MAX_MEM_PER_SESSION  \
+		(NFSD_CACHE_SIZE_SLOTS_PER_SESSION * NFSD_SLOT_CACHE_SIZE)
+
+struct nfsd4_slot {
+	u32	sl_seqid;
+	__be32	sl_status;
+	struct svc_cred sl_cred;
+	u32	sl_datalen;
+	u16	sl_opcnt;
+#define NFSD4_SLOT_INUSE	(1 << 0)
+#define NFSD4_SLOT_CACHETHIS	(1 << 1)
+#define NFSD4_SLOT_INITIALIZED	(1 << 2)
+#define NFSD4_SLOT_CACHED	(1 << 3)
+	u8	sl_flags;
+	char	sl_data[];
+};
+
+struct nfsd4_channel_attrs {
+	u32		headerpadsz;
+	u32		maxreq_sz;
+	u32		maxresp_sz;
+	u32		maxresp_cached;
+	u32		maxops;
+	u32		maxreqs;
+	u32		nr_rdma_attrs;
+	u32		rdma_attrs;
+};
+
+struct nfsd4_cb_sec {
+	u32	flavor; /* (u32)(-1) used to mean "no valid flavor" */
+	kuid_t	uid;
+	kgid_t	gid;
+};
+
+struct nfsd4_create_session {
+	clientid_t			clientid;
+	struct nfs4_sessionid		sessionid;
+	u32				seqid;
+	u32				flags;
+	struct nfsd4_channel_attrs	fore_channel;
+	struct nfsd4_channel_attrs	back_channel;
+	u32				callback_prog;
+	struct nfsd4_cb_sec		cb_sec;
+};
+
+struct nfsd4_backchannel_ctl {
+	u32	bc_cb_program;
+	struct nfsd4_cb_sec		bc_cb_sec;
+};
+
+struct nfsd4_bind_conn_to_session {
+	struct nfs4_sessionid		sessionid;
+	u32				dir;
+};
+
+/* The single slot clientid cache structure */
+struct nfsd4_clid_slot {
+	u32				sl_seqid;
+	__be32				sl_status;
+	struct nfsd4_create_session	sl_cr_ses;
+};
+
+struct nfsd4_conn {
+	struct list_head cn_persession;
+	struct svc_xprt *cn_xprt;
+	struct svc_xpt_user cn_xpt_user;
+	struct nfsd4_session *cn_session;
+/* CDFC4_FORE, CDFC4_BACK: */
+	unsigned char cn_flags;
+};
+
+/*
+ * Representation of a v4.1+ session. These are refcounted in a similar fashion
+ * to the nfs4_client. References are only taken when the server is actively
+ * working on the object (primarily during the processing of compounds).
+ */
+struct nfsd4_session {
+	atomic_t		se_ref;
+	struct list_head	se_hash;	/* hash by sessionid */
+	struct list_head	se_perclnt;
+/* See SESSION4_PERSIST, etc. for standard flags; this is internal-only: */
+#define NFS4_SESSION_DEAD	0x010
+	u32			se_flags;
+	struct nfs4_client	*se_client;
+	struct nfs4_sessionid	se_sessionid;
+	struct nfsd4_channel_attrs se_fchannel;
+	struct nfsd4_channel_attrs se_bchannel;
+	struct nfsd4_cb_sec	se_cb_sec;
+	struct list_head	se_conns;
+	u32			se_cb_prog;
+	u32			se_cb_seq_nr;
+	struct nfsd4_slot	*se_slots[];	/* forward channel slots */
+};
+
+/* formatted contents of nfs4_sessionid */
+struct nfsd4_sessionid {
+	clientid_t	clientid;
+	u32		sequence;
+	u32		reserved;
+};
+
+#define HEXDIR_LEN     33 /* hex version of 16 byte md5 of cl_name plus '\0' */
+
+/*
+ *       State                Meaning                  Where set
+ * --------------------------------------------------------------------------
+ * | NFSD4_ACTIVE      | Confirmed, active    | Default                     |
+ * |------------------- ----------------------------------------------------|
+ * | NFSD4_COURTESY    | Courtesy state.      | nfs4_get_client_reaplist    |
+ * |                   | Lease/lock/share     |                             |
+ * |                   | reservation conflict |                             |
+ * |                   | can cause Courtesy   |                             |
+ * |                   | client to be expired |                             |
+ * |------------------------------------------------------------------------|
+ * | NFSD4_EXPIRABLE   | Courtesy client to be| nfs4_laundromat             |
+ * |                   | expired by Laundromat| try_to_expire_client        |
+ * |                   | due to conflict      |                             |
+ * |------------------------------------------------------------------------|
+ */
+enum {
+	NFSD4_ACTIVE = 0,
+	NFSD4_COURTESY,
+	NFSD4_EXPIRABLE,
+};
+
+/*
+ * struct nfs4_client - one per client.  Clientids live here.
+ *
+ * The initial object created by an NFS client using SETCLIENTID (for NFSv4.0)
+ * or EXCHANGE_ID (for NFSv4.1+). These objects are refcounted and timestamped.
+ * Each nfsd_net_ns object contains a set of these and they are tracked via
+ * short and long form clientid. They are hashed and searched for under the
+ * per-nfsd_net client_lock spinlock.
+ *
+ * References to it are only held during the processing of compounds, and in
+ * certain other operations. In their "resting state" they have a refcount of
+ * 0. If they are not renewed within a lease period, they become eligible for
+ * destruction by the laundromat.
+ *
+ * These objects can also be destroyed prematurely by the fault injection code,
+ * or if the client sends certain forms of SETCLIENTID or EXCHANGE_ID updates.
+ * Care is taken *not* to do this however when the objects have an elevated
+ * refcount.
+ *
+ * o Each nfs4_client is hashed by clientid
+ *
+ * o Each nfs4_clients is also hashed by name (the opaque quantity initially
+ *   sent by the client to identify itself).
+ * 	  
+ * o cl_perclient list is used to ensure no dangling stateowner references
+ *   when we expire the nfs4_client
+ */
+struct nfs4_client {
+	struct list_head	cl_idhash; 	/* hash by cl_clientid.id */
+	struct rb_node		cl_namenode;	/* link into by-name trees */
+	struct list_head	*cl_ownerstr_hashtbl;
+	struct list_head	cl_openowners;
+	struct idr		cl_stateids;	/* stateid lookup */
+	struct list_head	cl_delegations;
+	struct list_head	cl_revoked;	/* unacknowledged, revoked 4.1 state */
+	struct list_head        cl_lru;         /* tail queue */
+#ifdef CONFIG_NFSD_PNFS
+	struct list_head	cl_lo_states;	/* outstanding layout states */
+#endif
+	struct xdr_netobj	cl_name; 	/* id generated by client */
+	nfs4_verifier		cl_verifier; 	/* generated by client */
+	time64_t		cl_time;	/* time of last lease renewal */
+	struct sockaddr_storage	cl_addr; 	/* client ipaddress */
+	bool			cl_mach_cred;	/* SP4_MACH_CRED in force */
+	struct svc_cred		cl_cred; 	/* setclientid principal */
+	clientid_t		cl_clientid;	/* generated by server */
+	nfs4_verifier		cl_confirm;	/* generated by server */
+	u32			cl_minorversion;
+	/* NFSv4.1 client implementation id: */
+	struct xdr_netobj	cl_nii_domain;
+	struct xdr_netobj	cl_nii_name;
+	struct timespec64	cl_nii_time;
+
+	/* for v4.0 and v4.1 callbacks: */
+	struct nfs4_cb_conn	cl_cb_conn;
+#define NFSD4_CLIENT_CB_UPDATE		(0)
+#define NFSD4_CLIENT_CB_KILL		(1)
+#define NFSD4_CLIENT_STABLE		(2)	/* client on stable storage */
+#define NFSD4_CLIENT_RECLAIM_COMPLETE	(3)	/* reclaim_complete done */
+#define NFSD4_CLIENT_CONFIRMED		(4)	/* client is confirmed */
+#define NFSD4_CLIENT_UPCALL_LOCK	(5)	/* upcall serialization */
+#define NFSD4_CLIENT_CB_FLAG_MASK	(1 << NFSD4_CLIENT_CB_UPDATE | \
+					 1 << NFSD4_CLIENT_CB_KILL)
+	unsigned long		cl_flags;
+	const struct cred	*cl_cb_cred;
+	struct rpc_clnt		*cl_cb_client;
+	u32			cl_cb_ident;
+#define NFSD4_CB_UP		0
+#define NFSD4_CB_UNKNOWN	1
+#define NFSD4_CB_DOWN		2
+#define NFSD4_CB_FAULT		3
+	int			cl_cb_state;
+	struct nfsd4_callback	cl_cb_null;
+	struct nfsd4_session	*cl_cb_session;
+
+	/* for all client information that callback code might need: */
+	spinlock_t		cl_lock;
+
+	/* for nfs41 */
+	struct list_head	cl_sessions;
+	struct nfsd4_clid_slot	cl_cs_slot;	/* create_session slot */
+	u32			cl_exchange_flags;
+	/* number of rpc's in progress over an associated session: */
+	atomic_t		cl_rpc_users;
+	struct nfsdfs_client	cl_nfsdfs;
+	struct nfs4_op_map      cl_spo_must_allow;
+
+	/* debugging info directory under nfsd/clients/ : */
+	struct dentry		*cl_nfsd_dentry;
+	/* 'info' file within that directory. Ref is not counted,
+	 * but will remain valid iff cl_nfsd_dentry != NULL
+	 */
+	struct dentry		*cl_nfsd_info_dentry;
+
+	/* for nfs41 callbacks */
+	/* We currently support a single back channel with a single slot */
+	unsigned long		cl_cb_slot_busy;
+	struct rpc_wait_queue	cl_cb_waitq;	/* backchannel callers may */
+						/* wait here for slots */
+	struct net		*net;
+	struct list_head	async_copies;	/* list of async copies */
+	spinlock_t		async_lock;	/* lock for async copies */
+	atomic_t		cl_cb_inflight;	/* Outstanding callbacks */
+
+	unsigned int		cl_state;
+	atomic_t		cl_delegs_in_recall;
+};
+
+/* struct nfs4_client_reset
+ * one per old client. Populates reset_str_hashtbl. Filled from conf_id_hashtbl
+ * upon lease reset, or from upcall to state_daemon (to read in state
+ * from non-volitile storage) upon reboot.
+ */
+struct nfs4_client_reclaim {
+	struct list_head	cr_strhash;	/* hash by cr_name */
+	struct nfs4_client	*cr_clp;	/* pointer to associated clp */
+	struct xdr_netobj	cr_name;	/* recovery dir name */
+	struct xdr_netobj	cr_princhash;
+};
+
+/* A reasonable value for REPLAY_ISIZE was estimated as follows:  
+ * The OPEN response, typically the largest, requires 
+ *   4(status) + 8(stateid) + 20(changeinfo) + 4(rflags) +  8(verifier) + 
+ *   4(deleg. type) + 8(deleg. stateid) + 4(deleg. recall flag) + 
+ *   20(deleg. space limit) + ~32(deleg. ace) = 112 bytes 
+ */
+
+#define NFSD4_REPLAY_ISIZE       112 
+
+/*
+ * Replay buffer, where the result of the last seqid-mutating operation 
+ * is cached. 
+ */
+struct nfs4_replay {
+	__be32			rp_status;
+	unsigned int		rp_buflen;
+	char			*rp_buf;
+	struct knfsd_fh		rp_openfh;
+	struct mutex		rp_mutex;
+	char			rp_ibuf[NFSD4_REPLAY_ISIZE];
+};
+
+struct nfs4_stateowner;
+
+struct nfs4_stateowner_operations {
+	void (*so_unhash)(struct nfs4_stateowner *);
+	void (*so_free)(struct nfs4_stateowner *);
+};
+
+/*
+ * A core object that represents either an open or lock owner. The object and
+ * lock owner objects have one of these embedded within them. Refcounts and
+ * other fields common to both owner types are contained within these
+ * structures.
+ */
+struct nfs4_stateowner {
+	struct list_head			so_strhash;
+	struct list_head			so_stateids;
+	struct nfs4_client			*so_client;
+	const struct nfs4_stateowner_operations	*so_ops;
+	/* after increment in nfsd4_bump_seqid, represents the next
+	 * sequence id expected from the client: */
+	atomic_t				so_count;
+	u32					so_seqid;
+	struct xdr_netobj			so_owner; /* open owner name */
+	struct nfs4_replay			so_replay;
+	bool					so_is_open_owner;
+};
+
+/*
+ * When a file is opened, the client provides an open state owner opaque string
+ * that indicates the "owner" of that open. These objects are refcounted.
+ * References to it are held by each open state associated with it. This object
+ * is a superset of the nfs4_stateowner struct.
+ */
+struct nfs4_openowner {
+	struct nfs4_stateowner	oo_owner; /* must be first field */
+	struct list_head        oo_perclient;
+	/*
+	 * We keep around openowners a little while after last close,
+	 * which saves clients from having to confirm, and allows us to
+	 * handle close replays if they come soon enough.  The close_lru
+	 * is a list of such openowners, to be reaped by the laundromat
+	 * thread eventually if they remain unused:
+	 */
+	struct list_head	oo_close_lru;
+	struct nfs4_ol_stateid *oo_last_closed_stid;
+	time64_t		oo_time; /* time of placement on so_close_lru */
+#define NFS4_OO_CONFIRMED   1
+	unsigned char		oo_flags;
+};
+
+/*
+ * Represents a generic "lockowner". Similar to an openowner. References to it
+ * are held by the lock stateids that are created on its behalf. This object is
+ * a superset of the nfs4_stateowner struct.
+ */
+struct nfs4_lockowner {
+	struct nfs4_stateowner	lo_owner;	/* must be first element */
+	struct list_head	lo_blocked;	/* blocked file_locks */
+};
+
+static inline struct nfs4_openowner * openowner(struct nfs4_stateowner *so)
+{
+	return container_of(so, struct nfs4_openowner, oo_owner);
+}
+
+static inline struct nfs4_lockowner * lockowner(struct nfs4_stateowner *so)
+{
+	return container_of(so, struct nfs4_lockowner, lo_owner);
+}
+
+/*
+ * Per-client state indicating no. of opens and outstanding delegations
+ * on a file from a particular client.'od' stands for 'open & delegation'
+ */
+struct nfs4_clnt_odstate {
+	struct nfs4_client	*co_client;
+	struct nfs4_file	*co_file;
+	struct list_head	co_perfile;
+	refcount_t		co_odcount;
+};
+
+/*
+ * nfs4_file: a file opened by some number of (open) nfs4_stateowners.
+ *
+ * These objects are global. nfsd keeps one instance of a nfs4_file per
+ * filehandle (though it may keep multiple file descriptors for each). Each
+ * inode can have multiple filehandles associated with it, so there is
+ * (potentially) a many to one relationship between this struct and struct
+ * inode.
+ *
+ * These are hashed by filehandle in the file_hashtbl, which is protected by
+ * the global state_lock spinlock.
+ */
+struct nfs4_file {
+	refcount_t		fi_ref;
+	struct inode *		fi_inode;
+	bool			fi_aliased;
+	spinlock_t		fi_lock;
+	struct hlist_node       fi_hash;	/* hash on fi_fhandle */
+	struct list_head        fi_stateids;
+	union {
+		struct list_head	fi_delegations;
+		struct rcu_head		fi_rcu;
+	};
+	struct list_head	fi_clnt_odstate;
+	/* One each for O_RDONLY, O_WRONLY, O_RDWR: */
+	struct nfsd_file	*fi_fds[3];
+	/*
+	 * Each open or lock stateid contributes 0-4 to the counts
+	 * below depending on which bits are set in st_access_bitmap:
+	 *     1 to fi_access[O_RDONLY] if NFS4_SHARE_ACCES_READ is set
+	 *   + 1 to fi_access[O_WRONLY] if NFS4_SHARE_ACCESS_WRITE is set
+	 *   + 1 to both of the above if NFS4_SHARE_ACCESS_BOTH is set.
+	 */
+	atomic_t		fi_access[2];
+	u32			fi_share_deny;
+	struct nfsd_file	*fi_deleg_file;
+	int			fi_delegees;
+	struct knfsd_fh		fi_fhandle;
+	bool			fi_had_conflict;
+#ifdef CONFIG_NFSD_PNFS
+	struct list_head	fi_lo_states;
+	atomic_t		fi_lo_recalls;
+#endif
+};
+
+/*
+ * A generic struct representing either a open or lock stateid. The nfs4_client
+ * holds a reference to each of these objects, and they in turn hold a
+ * reference to their respective stateowners. The client's reference is
+ * released in response to a close or unlock (depending on whether it's an open
+ * or lock stateid) or when the client is being destroyed.
+ *
+ * In the case of v4.0 open stateids, these objects are preserved for a little
+ * while after close in order to handle CLOSE replays. Those are eventually
+ * reclaimed via a LRU scheme by the laundromat.
+ *
+ * This object is a superset of the nfs4_stid. "ol" stands for "Open or Lock".
+ * Better suggestions welcome.
+ */
+struct nfs4_ol_stateid {
+	struct nfs4_stid		st_stid;
+	struct list_head		st_perfile;
+	struct list_head		st_perstateowner;
+	struct list_head		st_locks;
+	struct nfs4_stateowner		*st_stateowner;
+	struct nfs4_clnt_odstate	*st_clnt_odstate;
+/*
+ * These bitmasks use 3 separate bits for READ, ALLOW, and BOTH; see the
+ * comment above bmap_to_share_mode() for explanation:
+ */
+	unsigned char			st_access_bmap;
+	unsigned char			st_deny_bmap;
+	struct nfs4_ol_stateid		*st_openstp;
+	struct mutex			st_mutex;
+};
+
+static inline struct nfs4_ol_stateid *openlockstateid(struct nfs4_stid *s)
+{
+	return container_of(s, struct nfs4_ol_stateid, st_stid);
+}
+
+struct nfs4_layout_stateid {
+	struct nfs4_stid		ls_stid;
+	struct list_head		ls_perclnt;
+	struct list_head		ls_perfile;
+	spinlock_t			ls_lock;
+	struct list_head		ls_layouts;
+	u32				ls_layout_type;
+	struct nfsd_file		*ls_file;
+	struct nfsd4_callback		ls_recall;
+	stateid_t			ls_recall_sid;
+	bool				ls_recalled;
+	struct mutex			ls_mutex;
+};
+
+static inline struct nfs4_layout_stateid *layoutstateid(struct nfs4_stid *s)
+{
+	return container_of(s, struct nfs4_layout_stateid, ls_stid);
+}
+
+/* flags for preprocess_seqid_op() */
+#define RD_STATE	        0x00000010
+#define WR_STATE	        0x00000020
+
+enum nfsd4_cb_op {
+	NFSPROC4_CLNT_CB_NULL = 0,
+	NFSPROC4_CLNT_CB_RECALL,
+	NFSPROC4_CLNT_CB_LAYOUT,
+	NFSPROC4_CLNT_CB_OFFLOAD,
+	NFSPROC4_CLNT_CB_SEQUENCE,
+	NFSPROC4_CLNT_CB_NOTIFY_LOCK,
+};
+
+/* Returns true iff a is later than b: */
+static inline bool nfsd4_stateid_generation_after(stateid_t *a, stateid_t *b)
+{
+	return (s32)(a->si_generation - b->si_generation) > 0;
+}
+
+/*
+ * When a client tries to get a lock on a file, we set one of these objects
+ * on the blocking lock. When the lock becomes free, we can then issue a
+ * CB_NOTIFY_LOCK to the server.
+ */
+struct nfsd4_blocked_lock {
+	struct list_head	nbl_list;
+	struct list_head	nbl_lru;
+	time64_t		nbl_time;
+	struct file_lock	nbl_lock;
+	struct knfsd_fh		nbl_fh;
+	struct nfsd4_callback	nbl_cb;
+	struct kref		nbl_kref;
+};
+
+struct nfsd4_compound_state;
+struct nfsd_net;
+struct nfsd4_copy;
+
+extern __be32 nfs4_preprocess_stateid_op(struct svc_rqst *rqstp,
+		struct nfsd4_compound_state *cstate, struct svc_fh *fhp,
+		stateid_t *stateid, int flags, struct nfsd_file **filp,
+		struct nfs4_stid **cstid);
+__be32 nfsd4_lookup_stateid(struct nfsd4_compound_state *cstate,
+		     stateid_t *stateid, unsigned char typemask,
+		     struct nfs4_stid **s, struct nfsd_net *nn);
+struct nfs4_stid *nfs4_alloc_stid(struct nfs4_client *cl, struct kmem_cache *slab,
+				  void (*sc_free)(struct nfs4_stid *));
+int nfs4_init_copy_state(struct nfsd_net *nn, struct nfsd4_copy *copy);
+void nfs4_free_copy_state(struct nfsd4_copy *copy);
+struct nfs4_cpntf_state *nfs4_alloc_init_cpntf_state(struct nfsd_net *nn,
+			struct nfs4_stid *p_stid);
+void nfs4_unhash_stid(struct nfs4_stid *s);
+void nfs4_put_stid(struct nfs4_stid *s);
+void nfs4_inc_and_copy_stateid(stateid_t *dst, struct nfs4_stid *stid);
+void nfs4_remove_reclaim_record(struct nfs4_client_reclaim *, struct nfsd_net *);
+extern void nfs4_release_reclaim(struct nfsd_net *);
+extern struct nfs4_client_reclaim *nfsd4_find_reclaim_client(struct xdr_netobj name,
+							struct nfsd_net *nn);
+extern __be32 nfs4_check_open_reclaim(struct nfs4_client *);
+extern void nfsd4_probe_callback(struct nfs4_client *clp);
+extern void nfsd4_probe_callback_sync(struct nfs4_client *clp);
+extern void nfsd4_change_callback(struct nfs4_client *clp, struct nfs4_cb_conn *);
+extern void nfsd4_init_cb(struct nfsd4_callback *cb, struct nfs4_client *clp,
+		const struct nfsd4_callback_ops *ops, enum nfsd4_cb_op op);
+extern bool nfsd4_run_cb(struct nfsd4_callback *cb);
+extern int nfsd4_create_callback_queue(void);
+extern void nfsd4_destroy_callback_queue(void);
+extern void nfsd4_shutdown_callback(struct nfs4_client *);
+extern void nfsd4_shutdown_copy(struct nfs4_client *clp);
+extern struct nfs4_client_reclaim *nfs4_client_to_reclaim(struct xdr_netobj name,
+				struct xdr_netobj princhash, struct nfsd_net *nn);
+extern bool nfs4_has_reclaimed_state(struct xdr_netobj name, struct nfsd_net *nn);
+
+void put_nfs4_file(struct nfs4_file *fi);
+extern struct nfsd4_copy *
+find_async_copy(struct nfs4_client *clp, stateid_t *staetid);
+extern void nfs4_put_cpntf_state(struct nfsd_net *nn,
+				 struct nfs4_cpntf_state *cps);
+extern __be32 manage_cpntf_state(struct nfsd_net *nn, stateid_t *st,
+				 struct nfs4_client *clp,
+				 struct nfs4_cpntf_state **cps);
+static inline void get_nfs4_file(struct nfs4_file *fi)
+{
+	refcount_inc(&fi->fi_ref);
+}
+struct nfsd_file *find_any_file(struct nfs4_file *f);
+
+/* grace period management */
+void nfsd4_end_grace(struct nfsd_net *nn);
+
+/* nfs4recover operations */
+extern int nfsd4_client_tracking_init(struct net *net);
+extern void nfsd4_client_tracking_exit(struct net *net);
+extern void nfsd4_client_record_create(struct nfs4_client *clp);
+extern void nfsd4_client_record_remove(struct nfs4_client *clp);
+extern int nfsd4_client_record_check(struct nfs4_client *clp);
+extern void nfsd4_record_grace_done(struct nfsd_net *nn);
+
+static inline bool try_to_expire_client(struct nfs4_client *clp)
+{
+	cmpxchg(&clp->cl_state, NFSD4_COURTESY, NFSD4_EXPIRABLE);
+	return clp->cl_state == NFSD4_EXPIRABLE;
+}
+#endif   /* NFSD4_STATE_H */