linux/fs/nfsd/netns.h
Amir Goldstein e567b98ce9 nfsd: protect concurrent access to nfsd stats counters
nfsd stats counters can be updated by concurrent nfsd threads without any
protection.

Convert some nfsd_stats and nfsd_net struct members to use percpu counters.

The longest_chain* members of struct nfsd_net remain unprotected.

Signed-off-by: Amir Goldstein <amir73il@gmail.com>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2021-01-25 09:36:27 -05:00

193 lines
5.0 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>
#include <linux/percpu_counter.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;
enum {
/* cache misses due only to checksum comparison failures */
NFSD_NET_PAYLOAD_MISSES,
/* amount of memory (in bytes) currently consumed by the DRC */
NFSD_NET_DRC_MEM_USAGE,
NFSD_NET_COUNTERS_NUM
};
/*
* 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;
/* 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.
* The longest_chain* fields are modified with only the per-bucket
* cache lock, which isn't really safe and should be fixed if we want
* these statistics to be completely accurate.
*/
/* total number of entries */
atomic_t num_drc_entries;
/* Per-netns stats counters */
struct percpu_counter counter[NFSD_NET_COUNTERS_NUM];
/* 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;
/* utsname taken from the process that starts the server */
char nfsd_name[UNX_MAXNODENAME+1];
};
/* 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__ */