GitHub-Mirror/linux-bl808
2
0
Fork 0
mirror of https://github.com/Fishwaldo/linux-bl808.git synced 2025-06-17 20:25:19 +00:00
Code Issues Projects Releases Packages Wiki Activity Actions

NFS: DNS resolver cache per network namespace context introduced

Browse source 
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 <skinsbursky@parallels.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
This commit is contained in:
Stanislav Kinsbursky 2011-11-25 17:13:04 +03:00 • committed by Trond Myklebust
parent 5c1cacb175
commit 1b340d0118
5 changed files with 123 additions and 41 deletions
Download patch file Download diff file Expand all files Collapse all files

96
fs/nfs/dns_resolve.c
View file

@ -11,7 +11,7 @@
#include <linux/sunrpc/clnt.h>
#include <linux/dns_resolver.h>
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