path: root/fs/nfsd/state.h

/*
 *  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		stid;
#define NFS4_COPY_STID 1
#define NFS4_COPYNOTIFY_STID 2
	unsigned char		sc_type;
	refcount_t		sc_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;
};

#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	16
/* 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' */

/*
 * 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 */
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