alistair23-linux/fs/nfsd/netns.h
Arnd Bergmann 20b7d86f29 nfsd: use boottime for lease expiry calculation
A couple of time_t variables are only used to track the state of the
lease time and its expiration. The code correctly uses the 'time_after()'
macro to make this work on 32-bit architectures even beyond year 2038,
but the get_seconds() function and the time_t type itself are deprecated
as they behave inconsistently between 32-bit and 64-bit architectures
and often lead to code that is not y2038 safe.

As a minor issue, using get_seconds() leads to problems with concurrent
settimeofday() or clock_settime() calls, in the worst case timeout never
triggering after the time has been set backwards.

Change nfsd to use time64_t and ktime_get_boottime_seconds() here. This
is clearly excessive, as boottime by itself means we never go beyond 32
bits, but it does mean we handle this correctly and consistently without
having to worry about corner cases and should be no more expensive than
the previous implementation on 64-bit architectures.

The max_cb_time() function gets changed in order to avoid an expensive
64-bit division operation, but as the lease time is at most one hour,
there is no change in behavior.

Also do the same for server-to-server copy expiration time.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
[bfields@redhat.com: fix up copy expiration]
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2019-12-19 22:07:17 -05:00

187 lines
4.9 KiB
C

/* SPDX-License-Identifier: GPL-2.0-or-later */
/*
* per net namespace data structures for nfsd
*
* Copyright (C) 2012, Jeff Layton <jlayton@redhat.com>
*/
#ifndef __NFSD_NETNS_H__
#define __NFSD_NETNS_H__
#include <net/net_namespace.h>
#include <net/netns/generic.h>
/* Hash tables for nfs4_clientid state */
#define CLIENT_HASH_BITS 4
#define CLIENT_HASH_SIZE (1 << CLIENT_HASH_BITS)
#define CLIENT_HASH_MASK (CLIENT_HASH_SIZE - 1)
#define SESSION_HASH_SIZE 512
struct cld_net;
struct nfsd4_client_tracking_ops;
/*
* Represents a nfsd "container". With respect to nfsv4 state tracking, the
* fields of interest are the *_id_hashtbls and the *_name_tree. These track
* the nfs4_client objects by either short or long form clientid.
*
* Each nfsd_net runs a nfs4_laundromat workqueue job when necessary to clean
* up expired clients and delegations within the container.
*/
struct nfsd_net {
struct cld_net *cld_net;
struct cache_detail *svc_expkey_cache;
struct cache_detail *svc_export_cache;
struct cache_detail *idtoname_cache;
struct cache_detail *nametoid_cache;
struct lock_manager nfsd4_manager;
bool grace_ended;
time64_t boot_time;
/* internal mount of the "nfsd" pseudofilesystem: */
struct vfsmount *nfsd_mnt;
struct dentry *nfsd_client_dir;
/*
* reclaim_str_hashtbl[] holds known client info from previous reset/reboot
* used in reboot/reset lease grace period processing
*
* conf_id_hashtbl[], and conf_name_tree hold confirmed
* setclientid_confirmed info.
*
* unconf_str_hastbl[] and unconf_name_tree hold unconfirmed
* setclientid info.
*/
struct list_head *reclaim_str_hashtbl;
int reclaim_str_hashtbl_size;
struct list_head *conf_id_hashtbl;
struct rb_root conf_name_tree;
struct list_head *unconf_id_hashtbl;
struct rb_root unconf_name_tree;
struct list_head *sessionid_hashtbl;
/*
* client_lru holds client queue ordered by nfs4_client.cl_time
* for lease renewal.
*
* close_lru holds (open) stateowner queue ordered by nfs4_stateowner.so_time
* for last close replay.
*
* All of the above fields are protected by the client_mutex.
*/
struct list_head client_lru;
struct list_head close_lru;
struct list_head del_recall_lru;
/* protected by blocked_locks_lock */
struct list_head blocked_locks_lru;
struct delayed_work laundromat_work;
/* client_lock protects the client lru list and session hash table */
spinlock_t client_lock;
/* protects blocked_locks_lru */
spinlock_t blocked_locks_lock;
struct file *rec_file;
bool in_grace;
const struct nfsd4_client_tracking_ops *client_tracking_ops;
time64_t nfsd4_lease;
time64_t nfsd4_grace;
bool somebody_reclaimed;
bool track_reclaim_completes;
atomic_t nr_reclaim_complete;
bool nfsd_net_up;
bool lockd_up;
/* Time of server startup */
struct timespec64 nfssvc_boot;
seqlock_t boot_lock;
/*
* Max number of connections this nfsd container will allow. Defaults
* to '0' which is means that it bases this on the number of threads.
*/
unsigned int max_connections;
u32 clientid_base;
u32 clientid_counter;
u32 clverifier_counter;
struct svc_serv *nfsd_serv;
wait_queue_head_t ntf_wq;
atomic_t ntf_refcnt;
/*
* clientid and stateid data for construction of net unique COPY
* stateids.
*/
u32 s2s_cp_cl_id;
struct idr s2s_cp_stateids;
spinlock_t s2s_cp_lock;
/*
* Version information
*/
bool *nfsd_versions;
bool *nfsd4_minorversions;
/*
* Duplicate reply cache
*/
struct nfsd_drc_bucket *drc_hashtbl;
struct kmem_cache *drc_slab;
/* max number of entries allowed in the cache */
unsigned int max_drc_entries;
/* number of significant bits in the hash value */
unsigned int maskbits;
unsigned int drc_hashsize;
/*
* Stats and other tracking of on the duplicate reply cache.
* These fields and the "rc" fields in nfsdstats are modified
* with only the per-bucket cache lock, which isn't really safe
* and should be fixed if we want the statistics to be
* completely accurate.
*/
/* total number of entries */
atomic_t num_drc_entries;
/* cache misses due only to checksum comparison failures */
unsigned int payload_misses;
/* amount of memory (in bytes) currently consumed by the DRC */
unsigned int drc_mem_usage;
/* longest hash chain seen */
unsigned int longest_chain;
/* size of cache when we saw the longest hash chain */
unsigned int longest_chain_cachesize;
struct shrinker nfsd_reply_cache_shrinker;
};
/* Simple check to find out if a given net was properly initialized */
#define nfsd_netns_ready(nn) ((nn)->sessionid_hashtbl)
extern void nfsd_netns_free_versions(struct nfsd_net *nn);
extern unsigned int nfsd_net_id;
void nfsd_copy_boot_verifier(__be32 verf[2], struct nfsd_net *nn);
void nfsd_reset_boot_verifier(struct nfsd_net *nn);
#endif /* __NFSD_NETNS_H__ */