From 1b340d0118da1d7c60c664f17d7c8fce2bb1cd9d Mon Sep 17 00:00:00 2001 From: Stanislav Kinsbursky Date: Fri, 25 Nov 2011 17:13:04 +0300 Subject: [PATCH] NFS: DNS resolver cache per network namespace context introduced This patch implements DNS resolver cache creation and registration for each alive network namespace context. This was done by registering NFS per-net operations, responsible for DNS cache allocation/register and unregister/destructioning instead of initialization and destruction of static "nfs_dns_resolve" cache detail (this one was removed). Pointer to network dns resolver cache is stored in new per-net "nfs_net" structure. This patch also changes nfs_dns_resolve_name() function prototype (and it's calls) by adding network pointer parameter, which is used to get proper DNS resolver cache pointer for do_cache_lookup_wait() call. Note: empty nfs_dns_resolver_init() and nfs_dns_resolver_destroy() functions will be used in next patch in the series. Signed-off-by: Stanislav Kinsbursky Signed-off-by: Trond Myklebust --- fs/nfs/dns_resolve.c | 96 +++++++++++++++++++++++++++--------------- fs/nfs/dns_resolve.h | 14 +++++- fs/nfs/inode.c | 33 +++++++++++++-- fs/nfs/netns.h | 13 ++++++ fs/nfs/nfs4namespace.c | 8 ++-- 5 files changed, 123 insertions(+), 41 deletions(-) create mode 100644 fs/nfs/netns.h diff --git a/fs/nfs/dns_resolve.c b/fs/nfs/dns_resolve.c index 3cbf4b88f827..9aea78ab86ac 100644 --- a/fs/nfs/dns_resolve.c +++ b/fs/nfs/dns_resolve.c @@ -11,7 +11,7 @@ #include #include -ssize_t nfs_dns_resolve_name(char *name, size_t namelen, +ssize_t nfs_dns_resolve_name(struct net *net, char *name, size_t namelen, struct sockaddr *sa, size_t salen) { ssize_t ret; @@ -43,12 +43,11 @@ ssize_t nfs_dns_resolve_name(char *name, size_t namelen, #include "dns_resolve.h" #include "cache_lib.h" +#include "netns.h" #define NFS_DNS_HASHBITS 4 #define NFS_DNS_HASHTBL_SIZE (1 << NFS_DNS_HASHBITS) -static struct cache_head *nfs_dns_table[NFS_DNS_HASHTBL_SIZE]; - struct nfs_dns_ent { struct cache_head h; @@ -259,21 +258,6 @@ out: return ret; } -static struct cache_detail nfs_dns_resolve = { - .owner = THIS_MODULE, - .hash_size = NFS_DNS_HASHTBL_SIZE, - .hash_table = nfs_dns_table, - .name = "dns_resolve", - .cache_put = nfs_dns_ent_put, - .cache_upcall = nfs_dns_upcall, - .cache_parse = nfs_dns_parse, - .cache_show = nfs_dns_show, - .match = nfs_dns_match, - .init = nfs_dns_ent_init, - .update = nfs_dns_ent_update, - .alloc = nfs_dns_ent_alloc, -}; - static int do_cache_lookup(struct cache_detail *cd, struct nfs_dns_ent *key, struct nfs_dns_ent **item, @@ -336,8 +320,8 @@ out: return ret; } -ssize_t nfs_dns_resolve_name(char *name, size_t namelen, - struct sockaddr *sa, size_t salen) +ssize_t nfs_dns_resolve_name(struct net *net, char *name, + size_t namelen, struct sockaddr *sa, size_t salen) { struct nfs_dns_ent key = { .hostname = name, @@ -345,37 +329,83 @@ ssize_t nfs_dns_resolve_name(char *name, size_t namelen, }; struct nfs_dns_ent *item = NULL; ssize_t ret; + struct nfs_net *nn = net_generic(net, nfs_net_id); - ret = do_cache_lookup_wait(&nfs_dns_resolve, &key, &item); + ret = do_cache_lookup_wait(nn->nfs_dns_resolve, &key, &item); if (ret == 0) { if (salen >= item->addrlen) { memcpy(sa, &item->addr, item->addrlen); ret = item->addrlen; } else ret = -EOVERFLOW; - cache_put(&item->h, &nfs_dns_resolve); + cache_put(&item->h, nn->nfs_dns_resolve); } else if (ret == -ENOENT) ret = -ESRCH; return ret; } +int nfs_dns_resolver_cache_init(struct net *net) +{ + int err = -ENOMEM; + struct nfs_net *nn = net_generic(net, nfs_net_id); + struct cache_detail *cd; + struct cache_head **tbl; + + cd = kzalloc(sizeof(struct cache_detail), GFP_KERNEL); + if (cd == NULL) + goto err_cd; + + tbl = kzalloc(NFS_DNS_HASHTBL_SIZE * sizeof(struct cache_head *), + GFP_KERNEL); + if (tbl == NULL) + goto err_tbl; + + cd->owner = THIS_MODULE, + cd->hash_size = NFS_DNS_HASHTBL_SIZE, + cd->hash_table = tbl, + cd->name = "dns_resolve", + cd->cache_put = nfs_dns_ent_put, + cd->cache_upcall = nfs_dns_upcall, + cd->cache_parse = nfs_dns_parse, + cd->cache_show = nfs_dns_show, + cd->match = nfs_dns_match, + cd->init = nfs_dns_ent_init, + cd->update = nfs_dns_ent_update, + cd->alloc = nfs_dns_ent_alloc, + + nfs_cache_init(cd); + err = nfs_cache_register_net(net, cd); + if (err) + goto err_reg; + nn->nfs_dns_resolve = cd; + return 0; + +err_reg: + nfs_cache_destroy(cd); + kfree(cd->hash_table); +err_tbl: + kfree(cd); +err_cd: + return err; +} + +void nfs_dns_resolver_cache_destroy(struct net *net) +{ + struct nfs_net *nn = net_generic(net, nfs_net_id); + struct cache_detail *cd = nn->nfs_dns_resolve; + + nfs_cache_unregister_net(net, cd); + nfs_cache_destroy(cd); + kfree(cd->hash_table); + kfree(cd); +} + int nfs_dns_resolver_init(void) { - int err; - - nfs_cache_init(&nfs_dns_resolve); - err = nfs_cache_register_net(&init_net, &nfs_dns_resolve); - if (err) { - nfs_cache_destroy(&nfs_dns_resolve); - return err; - } return 0; } void nfs_dns_resolver_destroy(void) { - nfs_cache_unregister_net(&init_net, &nfs_dns_resolve); - nfs_cache_destroy(&nfs_dns_resolve); } - #endif diff --git a/fs/nfs/dns_resolve.h b/fs/nfs/dns_resolve.h index 199bb5543a91..2e4f596d2923 100644 --- a/fs/nfs/dns_resolve.h +++ b/fs/nfs/dns_resolve.h @@ -15,12 +15,22 @@ static inline int nfs_dns_resolver_init(void) static inline void nfs_dns_resolver_destroy(void) {} + +static inline int nfs_dns_resolver_cache_init(struct net *net) +{ + return 0; +} + +static inline void nfs_dns_resolver_cache_destroy(struct net *net) +{} #else extern int nfs_dns_resolver_init(void); extern void nfs_dns_resolver_destroy(void); +extern int nfs_dns_resolver_cache_init(struct net *net); +extern void nfs_dns_resolver_cache_destroy(struct net *net); #endif -extern ssize_t nfs_dns_resolve_name(char *name, size_t namelen, - struct sockaddr *sa, size_t salen); +extern ssize_t nfs_dns_resolve_name(struct net *net, char *name, + size_t namelen, struct sockaddr *sa, size_t salen); #endif diff --git a/fs/nfs/inode.c b/fs/nfs/inode.c index f649fba8c384..0335f6e4ff7e 100644 --- a/fs/nfs/inode.c +++ b/fs/nfs/inode.c @@ -51,6 +51,7 @@ #include "fscache.h" #include "dns_resolve.h" #include "pnfs.h" +#include "netns.h" #define NFSDBG_FACILITY NFSDBG_VFS @@ -1552,6 +1553,25 @@ static void nfsiod_stop(void) destroy_workqueue(wq); } +int nfs_net_id; + +static int nfs_net_init(struct net *net) +{ + return nfs_dns_resolver_cache_init(net); +} + +static void nfs_net_exit(struct net *net) +{ + nfs_dns_resolver_cache_destroy(net); +} + +static struct pernet_operations nfs_net_ops = { + .init = nfs_net_init, + .exit = nfs_net_exit, + .id = &nfs_net_id, + .size = sizeof(struct nfs_net), +}; + /* * Initialize NFS */ @@ -1561,9 +1581,13 @@ static int __init init_nfs_fs(void) err = nfs_idmap_init(); if (err < 0) - goto out9; + goto out10; err = nfs_dns_resolver_init(); + if (err < 0) + goto out9; + + err = register_pernet_subsys(&nfs_net_ops); if (err < 0) goto out8; @@ -1625,10 +1649,12 @@ out5: out6: nfs_fscache_unregister(); out7: - nfs_dns_resolver_destroy(); + unregister_pernet_subsys(&nfs_net_ops); out8: - nfs_idmap_quit(); + nfs_dns_resolver_destroy(); out9: + nfs_idmap_quit(); +out10: return err; } @@ -1640,6 +1666,7 @@ static void __exit exit_nfs_fs(void) nfs_destroy_inodecache(); nfs_destroy_nfspagecache(); nfs_fscache_unregister(); + unregister_pernet_subsys(&nfs_net_ops); nfs_dns_resolver_destroy(); nfs_idmap_quit(); #ifdef CONFIG_PROC_FS diff --git a/fs/nfs/netns.h b/fs/nfs/netns.h new file mode 100644 index 000000000000..8c1f130d6ca2 --- /dev/null +++ b/fs/nfs/netns.h @@ -0,0 +1,13 @@ +#ifndef __NFS_NETNS_H__ +#define __NFS_NETNS_H__ + +#include +#include + +struct nfs_net { + struct cache_detail *nfs_dns_resolve; +}; + +extern int nfs_net_id; + +#endif diff --git a/fs/nfs/nfs4namespace.c b/fs/nfs/nfs4namespace.c index bb80c49b6533..919a36935924 100644 --- a/fs/nfs/nfs4namespace.c +++ b/fs/nfs/nfs4namespace.c @@ -94,13 +94,14 @@ static int nfs4_validate_fspath(struct dentry *dentry, } static size_t nfs_parse_server_name(char *string, size_t len, - struct sockaddr *sa, size_t salen) + struct sockaddr *sa, size_t salen, struct nfs_server *server) { ssize_t ret; ret = rpc_pton(string, len, sa, salen); if (ret == 0) { - ret = nfs_dns_resolve_name(string, len, sa, salen); + ret = nfs_dns_resolve_name(server->client->cl_xprt->xprt_net, + string, len, sa, salen); if (ret < 0) ret = 0; } @@ -137,7 +138,8 @@ static struct vfsmount *try_location(struct nfs_clone_mount *mountdata, continue; mountdata->addrlen = nfs_parse_server_name(buf->data, buf->len, - mountdata->addr, addr_bufsize); + mountdata->addr, addr_bufsize, + NFS_SB(mountdata->sb)); if (mountdata->addrlen == 0) continue;