linux/fs/nfsd/state.h
J. Bruce Fields acfdf5c383 nfsd4: acquire only one lease per file
Instead of acquiring one lease each time another client opens a file,
nfsd can acquire just one lease to represent all of them, and reference
count it to determine when to release it.

This fixes a regression introduced by
c45821d263 "locks: eliminate fl_mylease
callback": after that patch, only the struct file * is used to determine
who owns a given lease.  But since we recently converted the server to
share a single struct file per open, if we acquire multiple leases on
the same file from nfsd, it then becomes impossible on unlocking a lease
to determine which of those leases (all of whom share the same struct
file *) we meant to remove.

Thanks to Takashi Iwai <tiwai@suse.de> for catching a bug in a previous
version of this patch.

Tested-by: Takashi Iwai <tiwai@suse.de>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2011-02-14 10:35:19 -05:00

503 lines
16 KiB
C

/*
* 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/sunrpc/svc_xprt.h>
#include <linux/nfsd/nfsfh.h>
#include "nfsfh.h"
typedef struct {
u32 cl_boot;
u32 cl_id;
} clientid_t;
typedef struct {
u32 so_boot;
u32 so_stateownerid;
u32 so_fileid;
} stateid_opaque_t;
typedef struct {
u32 si_generation;
stateid_opaque_t si_opaque;
} stateid_t;
#define si_boot si_opaque.so_boot
#define si_stateownerid si_opaque.so_stateownerid
#define si_fileid si_opaque.so_fileid
#define STATEID_FMT "(%08x/%08x/%08x/%08x)"
#define STATEID_VAL(s) \
(s)->si_boot, \
(s)->si_stateownerid, \
(s)->si_fileid, \
(s)->si_generation
struct nfsd4_callback {
void *cb_op;
struct nfs4_client *cb_clp;
struct list_head cb_per_client;
u32 cb_minorversion;
struct rpc_message cb_msg;
const struct rpc_call_ops *cb_ops;
struct work_struct cb_work;
bool cb_done;
};
struct nfs4_delegation {
struct list_head dl_perfile;
struct list_head dl_perclnt;
struct list_head dl_recall_lru; /* delegation recalled */
atomic_t dl_count; /* ref count */
struct nfs4_client *dl_client;
struct nfs4_file *dl_file;
u32 dl_type;
time_t dl_time;
/* For recall: */
stateid_t dl_stateid;
struct knfsd_fh dl_fh;
int dl_retries;
struct nfsd4_callback 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 */
};
/* 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 1024
/* 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 {
bool sl_inuse;
bool sl_cachethis;
u16 sl_opcnt;
u32 sl_seqid;
__be32 sl_status;
u32 sl_datalen;
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_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;
u32 uid;
u32 gid;
};
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;
};
struct nfsd4_session {
struct kref se_ref;
struct list_head se_hash; /* hash by sessionid */
struct list_head se_perclnt;
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 list_head se_conns;
u32 se_cb_prog;
u32 se_cb_seq_nr;
struct nfsd4_slot *se_slots[]; /* forward channel slots */
};
static inline void
nfsd4_put_session(struct nfsd4_session *ses)
{
extern void free_session(struct kref *kref);
kref_put(&ses->se_ref, free_session);
}
static inline void
nfsd4_get_session(struct nfsd4_session *ses)
{
kref_get(&ses->se_ref);
}
/* 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.
* 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 list_head cl_strhash; /* hash by cl_name */
struct list_head cl_openowners;
struct list_head cl_delegations;
struct list_head cl_lru; /* tail queue */
struct xdr_netobj cl_name; /* id generated by client */
char cl_recdir[HEXDIR_LEN]; /* recovery dir */
nfs4_verifier cl_verifier; /* generated by client */
time_t cl_time; /* time of last lease renewal */
struct sockaddr_storage cl_addr; /* client ipaddress */
u32 cl_flavor; /* setclientid pseudoflavor */
char *cl_principal; /* setclientid principal name */
struct svc_cred cl_cred; /* setclientid principal */
clientid_t cl_clientid; /* generated by server */
nfs4_verifier cl_confirm; /* generated by server */
u32 cl_firststate; /* recovery dir creation */
u32 cl_minorversion;
/* for v4.0 and v4.1 callbacks: */
struct nfs4_cb_conn cl_cb_conn;
#define NFSD4_CLIENT_CB_UPDATE 1
#define NFSD4_CLIENT_KILL 2
unsigned long cl_cb_flags;
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
int cl_cb_state;
struct nfsd4_callback cl_cb_null;
struct nfsd4_session *cl_cb_session;
struct list_head cl_callbacks; /* list of in-progress callbacks */
/* 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_refcount;
/* 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 */
};
static inline void
mark_client_expired(struct nfs4_client *clp)
{
clp->cl_time = 0;
}
static inline bool
is_client_expired(struct nfs4_client *clp)
{
return clp->cl_time == 0;
}
/* 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 */
char cr_recdir[HEXDIR_LEN]; /* recover dir */
};
static inline void
update_stateid(stateid_t *stateid)
{
stateid->si_generation++;
}
/* 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;
unsigned intrp_allocated;
struct knfsd_fh rp_openfh;
char rp_ibuf[NFSD4_REPLAY_ISIZE];
};
/*
* nfs4_stateowner can either be an open_owner, or a lock_owner
*
* so_idhash: stateid_hashtbl[] for open owner, lockstateid_hashtbl[]
* for lock_owner
* so_strhash: ownerstr_hashtbl[] for open_owner, lock_ownerstr_hashtbl[]
* for lock_owner
* so_perclient: nfs4_client->cl_perclient entry - used when nfs4_client
* struct is reaped.
* so_perfilestate: heads the list of nfs4_stateid (either open or lock)
* and is used to ensure no dangling nfs4_stateid references when we
* release a stateowner.
* so_perlockowner: (open) nfs4_stateid->st_perlockowner entry - used when
* close is called to reap associated byte-range locks
* so_close_lru: (open) stateowner is placed on this list instead of being
* reaped (when so_perfilestate is empty) to hold the last close replay.
* reaped by laundramat thread after lease period.
*/
struct nfs4_stateowner {
struct kref so_ref;
struct list_head so_idhash; /* hash by so_id */
struct list_head so_strhash; /* hash by op_name */
struct list_head so_perclient;
struct list_head so_stateids;
struct list_head so_perstateid; /* for lockowners only */
struct list_head so_close_lru; /* tail queue */
time_t so_time; /* time of placement on so_close_lru */
int so_is_open_owner; /* 1=openowner,0=lockowner */
u32 so_id;
struct nfs4_client * so_client;
/* after increment in ENCODE_SEQID_OP_TAIL, represents the next
* sequence id expected from the client: */
u32 so_seqid;
struct xdr_netobj so_owner; /* open owner name */
int so_confirmed; /* successful OPEN_CONFIRM? */
struct nfs4_replay so_replay;
};
/*
* nfs4_file: a file opened by some number of (open) nfs4_stateowners.
* o fi_perfile list is used to search for conflicting
* share_acces, share_deny on the file.
*/
struct nfs4_file {
atomic_t fi_ref;
struct list_head fi_hash; /* hash by "struct inode *" */
struct list_head fi_stateids;
struct list_head fi_delegations;
/* One each for O_RDONLY, O_WRONLY, O_RDWR: */
struct file * fi_fds[3];
/* One each for O_RDONLY, O_WRONLY: */
atomic_t fi_access[2];
/*
* Each open stateid contributes 1 to either fi_readers or
* fi_writers, or both, depending on the open mode. A
* delegation also takes an fi_readers reference. Lock
* stateid's take none.
*/
atomic_t fi_readers;
atomic_t fi_writers;
struct file *fi_deleg_file;
struct file_lock *fi_lease;
atomic_t fi_delegees;
struct inode *fi_inode;
u32 fi_id; /* used with stateowner->so_id
* for stateid_hashtbl hash */
bool fi_had_conflict;
};
/* XXX: for first cut may fall back on returning file that doesn't work
* at all? */
static inline struct file *find_writeable_file(struct nfs4_file *f)
{
if (f->fi_fds[O_WRONLY])
return f->fi_fds[O_WRONLY];
return f->fi_fds[O_RDWR];
}
static inline struct file *find_readable_file(struct nfs4_file *f)
{
if (f->fi_fds[O_RDONLY])
return f->fi_fds[O_RDONLY];
return f->fi_fds[O_RDWR];
}
static inline struct file *find_any_file(struct nfs4_file *f)
{
if (f->fi_fds[O_RDWR])
return f->fi_fds[O_RDWR];
else if (f->fi_fds[O_WRONLY])
return f->fi_fds[O_WRONLY];
else
return f->fi_fds[O_RDONLY];
}
/*
* nfs4_stateid can either be an open stateid or (eventually) a lock stateid
*
* (open)nfs4_stateid: one per (open)nfs4_stateowner, nfs4_file
*
* st_hash: stateid_hashtbl[] entry or lockstateid_hashtbl entry
* st_perfile: file_hashtbl[] entry.
* st_perfile_state: nfs4_stateowner->so_perfilestate
* st_perlockowner: (open stateid) list of lock nfs4_stateowners
* st_access_bmap: used only for open stateid
* st_deny_bmap: used only for open stateid
* st_openstp: open stateid lock stateid was derived from
*
* XXX: open stateids and lock stateids have diverged sufficiently that
* we should consider defining separate structs for the two cases.
*/
struct nfs4_stateid {
struct list_head st_hash;
struct list_head st_perfile;
struct list_head st_perstateowner;
struct list_head st_lockowners;
struct nfs4_stateowner * st_stateowner;
struct nfs4_file * st_file;
stateid_t st_stateid;
unsigned long st_access_bmap;
unsigned long st_deny_bmap;
struct nfs4_stateid * st_openstp;
};
/* flags for preprocess_seqid_op() */
#define HAS_SESSION 0x00000001
#define CONFIRM 0x00000002
#define OPEN_STATE 0x00000004
#define LOCK_STATE 0x00000008
#define RD_STATE 0x00000010
#define WR_STATE 0x00000020
#define CLOSE_STATE 0x00000040
#define seqid_mutating_err(err) \
(((err) != nfserr_stale_clientid) && \
((err) != nfserr_bad_seqid) && \
((err) != nfserr_stale_stateid) && \
((err) != nfserr_bad_stateid))
struct nfsd4_compound_state;
extern __be32 nfs4_preprocess_stateid_op(struct nfsd4_compound_state *cstate,
stateid_t *stateid, int flags, struct file **filp);
extern void nfs4_lock_state(void);
extern void nfs4_unlock_state(void);
extern int nfs4_in_grace(void);
extern __be32 nfs4_check_open_reclaim(clientid_t *clid);
extern void nfs4_free_stateowner(struct kref *kref);
extern int set_callback_cred(void);
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_do_callback_rpc(struct work_struct *);
extern void nfsd4_cb_recall(struct nfs4_delegation *dp);
extern int nfsd4_create_callback_queue(void);
extern void nfsd4_destroy_callback_queue(void);
extern void nfsd4_shutdown_callback(struct nfs4_client *);
extern void nfs4_put_delegation(struct nfs4_delegation *dp);
extern __be32 nfs4_make_rec_clidname(char *clidname, struct xdr_netobj *clname);
extern void nfsd4_init_recdir(char *recdir_name);
extern int nfsd4_recdir_load(void);
extern void nfsd4_shutdown_recdir(void);
extern int nfs4_client_to_reclaim(const char *name);
extern int nfs4_has_reclaimed_state(const char *name, bool use_exchange_id);
extern void nfsd4_recdir_purge_old(void);
extern int nfsd4_create_clid_dir(struct nfs4_client *clp);
extern void nfsd4_remove_clid_dir(struct nfs4_client *clp);
extern void release_session_client(struct nfsd4_session *);
static inline void
nfs4_put_stateowner(struct nfs4_stateowner *so)
{
kref_put(&so->so_ref, nfs4_free_stateowner);
}
static inline void
nfs4_get_stateowner(struct nfs4_stateowner *so)
{
kref_get(&so->so_ref);
}
#endif /* NFSD4_STATE_H */