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[PATCH] knfsd: Change the store of auth_domains to not be a 'cache'
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The 'auth_domain's are simply handles on internal data structures.  They do
not cache information from user-space, and forcing them into the mold of a
'cache' misrepresents their true nature and causes confusion.

Signed-off-by: Neil Brown <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>
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@neilbrown
neilbrown authored and Linus Torvalds committed Mar 27, 2006
1 parent 3e7b191 commit efc36aa
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Showing 6 changed files with 81 additions and 145 deletions.
5 changes: 2 additions & 3 deletions fs/nfsd/export.c
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Original file line number Diff line number Diff line change
Expand Up @@ -242,7 +242,7 @@ static inline int svc_expkey_match (struct svc_expkey *a, struct svc_expkey *b)

static inline void svc_expkey_init(struct svc_expkey *new, struct svc_expkey *item)
{
cache_get(&item->ek_client->h);
kref_get(&item->ek_client->ref);
new->ek_client = item->ek_client;
new->ek_fsidtype = item->ek_fsidtype;
new->ek_fsid[0] = item->ek_fsid[0];
Expand Down Expand Up @@ -474,7 +474,7 @@ static inline int svc_export_match(struct svc_export *a, struct svc_export *b)
}
static inline void svc_export_init(struct svc_export *new, struct svc_export *item)
{
cache_get(&item->ex_client->h);
kref_get(&item->ex_client->ref);
new->ex_client = item->ex_client;
new->ex_dentry = dget(item->ex_dentry);
new->ex_mnt = mntget(item->ex_mnt);
Expand Down Expand Up @@ -1129,7 +1129,6 @@ exp_delclient(struct nfsctl_client *ncp)
*/
if (dom) {
err = auth_unix_forget_old(dom);
dom->h.expiry_time = get_seconds();
auth_domain_put(dom);
}

Expand Down
12 changes: 7 additions & 5 deletions include/linux/sunrpc/svcauth.h
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Original file line number Diff line number Diff line change
Expand Up @@ -45,9 +45,10 @@ struct svc_rqst; /* forward decl */
* of ip addresses to the given client.
*/
struct auth_domain {
struct cache_head h;
struct kref ref;
struct hlist_node hash;
char *name;
int flavour;
struct auth_ops *flavour;
};

/*
Expand Down Expand Up @@ -86,6 +87,9 @@ struct auth_domain {
*
* domain_release()
* This call releases a domain.
* set_client()
* Givens a pending request (struct svc_rqst), finds and assigns
* an appropriate 'auth_domain' as the client.
*/
struct auth_ops {
char * name;
Expand Down Expand Up @@ -117,7 +121,7 @@ extern void svc_auth_unregister(rpc_authflavor_t flavor);
extern struct auth_domain *unix_domain_find(char *name);
extern void auth_domain_put(struct auth_domain *item);
extern int auth_unix_add_addr(struct in_addr addr, struct auth_domain *dom);
extern struct auth_domain *auth_domain_lookup(struct auth_domain *item, int set);
extern struct auth_domain *auth_domain_lookup(char *name, struct auth_domain *new);
extern struct auth_domain *auth_domain_find(char *name);
extern struct auth_domain *auth_unix_lookup(struct in_addr addr);
extern int auth_unix_forget_old(struct auth_domain *dom);
Expand Down Expand Up @@ -160,8 +164,6 @@ static inline unsigned long hash_mem(char *buf, int length, int bits)
return hash >> (BITS_PER_LONG - bits);
}

extern struct cache_detail auth_domain_cache, ip_map_cache;

#endif /* __KERNEL__ */

#endif /* _LINUX_SUNRPC_SVCAUTH_H_ */
14 changes: 7 additions & 7 deletions net/sunrpc/auth_gss/svcauth_gss.c
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Original file line number Diff line number Diff line change
Expand Up @@ -645,6 +645,8 @@ find_gss_auth_domain(struct gss_ctx *ctx, u32 svc)
return auth_domain_find(name);
}

static struct auth_ops svcauthops_gss;

int
svcauth_gss_register_pseudoflavor(u32 pseudoflavor, char * name)
{
Expand All @@ -655,20 +657,18 @@ svcauth_gss_register_pseudoflavor(u32 pseudoflavor, char * name)
new = kmalloc(sizeof(*new), GFP_KERNEL);
if (!new)
goto out;
cache_init(&new->h.h);
kref_init(&new->h.ref);
new->h.name = kmalloc(strlen(name) + 1, GFP_KERNEL);
if (!new->h.name)
goto out_free_dom;
strcpy(new->h.name, name);
new->h.flavour = RPC_AUTH_GSS;
new->h.flavour = &svcauthops_gss;
new->pseudoflavor = pseudoflavor;
new->h.h.expiry_time = NEVER;

test = auth_domain_lookup(&new->h, 1);
if (test == &new->h) {
BUG_ON(atomic_dec_and_test(&new->h.h.refcnt));
} else { /* XXX Duplicate registration? */
test = auth_domain_lookup(name, &new->h);
if (test != &new->h) { /* XXX Duplicate registration? */
auth_domain_put(&new->h);
/* dangling ref-count... */
goto out;
}
return 0;
Expand Down
4 changes: 1 addition & 3 deletions net/sunrpc/sunrpc_syms.c
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Original file line number Diff line number Diff line change
Expand Up @@ -142,6 +142,7 @@ EXPORT_SYMBOL(nlm_debug);

extern int register_rpc_pipefs(void);
extern void unregister_rpc_pipefs(void);
extern struct cache_detail ip_map_cache;

static int __init
init_sunrpc(void)
Expand All @@ -158,7 +159,6 @@ init_sunrpc(void)
#ifdef CONFIG_PROC_FS
rpc_proc_init();
#endif
cache_register(&auth_domain_cache);
cache_register(&ip_map_cache);
out:
return err;
Expand All @@ -169,8 +169,6 @@ cleanup_sunrpc(void)
{
unregister_rpc_pipefs();
rpc_destroy_mempool();
if (cache_unregister(&auth_domain_cache))
printk(KERN_ERR "sunrpc: failed to unregister auth_domain cache\n");
if (cache_unregister(&ip_map_cache))
printk(KERN_ERR "sunrpc: failed to unregister ip_map cache\n");
#ifdef RPC_DEBUG
Expand Down
122 changes: 33 additions & 89 deletions net/sunrpc/svcauth.c
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Original file line number Diff line number Diff line change
Expand Up @@ -106,112 +106,56 @@ svc_auth_unregister(rpc_authflavor_t flavor)
EXPORT_SYMBOL(svc_auth_unregister);

/**************************************************
* cache for domain name to auth_domain
* Entries are only added by flavours which will normally
* have a structure that 'inherits' from auth_domain.
* e.g. when an IP -> domainname is given to auth_unix,
* and the domain name doesn't exist, it will create a
* auth_unix_domain and add it to this hash table.
* If it finds the name does exist, but isn't AUTH_UNIX,
* it will complain.
* 'auth_domains' are stored in a hash table indexed by name.
* When the last reference to an 'auth_domain' is dropped,
* the object is unhashed and freed.
* If auth_domain_lookup fails to find an entry, it will return
* it's second argument 'new'. If this is non-null, it will
* have been atomically linked into the table.
*/

/*
* Auth auth_domain cache is somewhat different to other caches,
* largely because the entries are possibly of different types:
* each auth flavour has it's own type.
* One consequence of this that DefineCacheLookup cannot
* allocate a new structure as it cannot know the size.
* Notice that the "INIT" code fragment is quite different
* from other caches. When auth_domain_lookup might be
* creating a new domain, the new domain is passed in
* complete and it is used as-is rather than being copied into
* another structure.
*/
#define DN_HASHBITS 6
#define DN_HASHMAX (1<<DN_HASHBITS)
#define DN_HASHMASK (DN_HASHMAX-1)

static struct cache_head *auth_domain_table[DN_HASHMAX];

static void auth_domain_drop(struct cache_head *item, struct cache_detail *cd)
{
struct auth_domain *dom = container_of(item, struct auth_domain, h);
if (cache_put(item,cd))
authtab[dom->flavour]->domain_release(dom);
}


struct cache_detail auth_domain_cache = {
.owner = THIS_MODULE,
.hash_size = DN_HASHMAX,
.hash_table = auth_domain_table,
.name = "auth.domain",
.cache_put = auth_domain_drop,
};
static struct hlist_head auth_domain_table[DN_HASHMAX];
static spinlock_t auth_domain_lock = SPIN_LOCK_UNLOCKED;

void auth_domain_put(struct auth_domain *dom)
{
auth_domain_drop(&dom->h, &auth_domain_cache);
}

static inline int auth_domain_hash(struct auth_domain *item)
{
return hash_str(item->name, DN_HASHBITS);
}
static inline int auth_domain_match(struct auth_domain *tmp, struct auth_domain *item)
{
return strcmp(tmp->name, item->name) == 0;
if (atomic_dec_and_lock(&dom->ref.refcount, &auth_domain_lock)) {
hlist_del(&dom->hash);
dom->flavour->domain_release(dom);
}
}

struct auth_domain *
auth_domain_lookup(struct auth_domain *item, int set)
auth_domain_lookup(char *name, struct auth_domain *new)
{
struct auth_domain *tmp = NULL;
struct cache_head **hp, **head;
head = &auth_domain_cache.hash_table[auth_domain_hash(item)];

if (set)
write_lock(&auth_domain_cache.hash_lock);
else
read_lock(&auth_domain_cache.hash_lock);
for (hp=head; *hp != NULL; hp = &tmp->h.next) {
tmp = container_of(*hp, struct auth_domain, h);
if (!auth_domain_match(tmp, item))
continue;
if (!set) {
cache_get(&tmp->h);
goto out_noset;
struct auth_domain *hp;
struct hlist_head *head;
struct hlist_node *np;

head = &auth_domain_table[hash_str(name, DN_HASHBITS)];

spin_lock(&auth_domain_lock);

hlist_for_each_entry(hp, np, head, hash) {
if (strcmp(hp->name, name)==0) {
kref_get(&hp->ref);
spin_unlock(&auth_domain_lock);
return hp;
}
*hp = tmp->h.next;
tmp->h.next = NULL;
auth_domain_drop(&tmp->h, &auth_domain_cache);
goto out_set;
}
/* Didn't find anything */
if (!set)
goto out_nada;
auth_domain_cache.entries++;
out_set:
item->h.next = *head;
*head = &item->h;
cache_get(&item->h);
write_unlock(&auth_domain_cache.hash_lock);
cache_fresh(&auth_domain_cache, &item->h, item->h.expiry_time);
cache_get(&item->h);
return item;
out_nada:
tmp = NULL;
out_noset:
read_unlock(&auth_domain_cache.hash_lock);
return tmp;
if (new) {
hlist_add_head(&new->hash, head);
kref_get(&new->ref);
}
spin_unlock(&auth_domain_lock);
return new;
}

struct auth_domain *auth_domain_find(char *name)
{
struct auth_domain *rv, ad;

ad.name = name;
rv = auth_domain_lookup(&ad, 0);
return rv;
return auth_domain_lookup(name, NULL);
}
69 changes: 31 additions & 38 deletions net/sunrpc/svcauth_unix.c
View file
Original file line number Diff line number Diff line change
Expand Up @@ -27,41 +27,35 @@ struct unix_domain {
/* other stuff later */
};

extern struct auth_ops svcauth_unix;

struct auth_domain *unix_domain_find(char *name)
{
struct auth_domain *rv, ud;
struct unix_domain *new;

ud.name = name;

rv = auth_domain_lookup(&ud, 0);

foundit:
if (rv && rv->flavour != RPC_AUTH_UNIX) {
auth_domain_put(rv);
return NULL;
}
if (rv)
return rv;

new = kmalloc(sizeof(*new), GFP_KERNEL);
if (new == NULL)
return NULL;
cache_init(&new->h.h);
new->h.name = kstrdup(name, GFP_KERNEL);
new->h.flavour = RPC_AUTH_UNIX;
new->addr_changes = 0;
new->h.h.expiry_time = NEVER;

rv = auth_domain_lookup(&new->h, 2);
if (rv == &new->h) {
if (atomic_dec_and_test(&new->h.h.refcnt)) BUG();
} else {
auth_domain_put(&new->h);
goto foundit;
struct auth_domain *rv;
struct unix_domain *new = NULL;

rv = auth_domain_lookup(name, NULL);
while(1) {
if (rv != &new->h) {
if (new) auth_domain_put(&new->h);
return rv;
}
if (rv && rv->flavour != &svcauth_unix) {
auth_domain_put(rv);
return NULL;
}
if (rv)
return rv;

new = kmalloc(sizeof(*new), GFP_KERNEL);
if (new == NULL)
return NULL;
kref_init(&new->h.ref);
new->h.name = kstrdup(name, GFP_KERNEL);
new->h.flavour = &svcauth_unix;
new->addr_changes = 0;
rv = auth_domain_lookup(name, &new->h);
}

return rv;
}

static void svcauth_unix_domain_release(struct auth_domain *dom)
Expand Down Expand Up @@ -130,7 +124,7 @@ static inline void ip_map_init(struct ip_map *new, struct ip_map *item)
}
static inline void ip_map_update(struct ip_map *new, struct ip_map *item)
{
cache_get(&item->m_client->h.h);
kref_get(&item->m_client->h.ref);
new->m_client = item->m_client;
new->m_add_change = item->m_add_change;
}
Expand Down Expand Up @@ -272,7 +266,7 @@ int auth_unix_add_addr(struct in_addr addr, struct auth_domain *dom)
struct unix_domain *udom;
struct ip_map ip, *ipmp;

if (dom->flavour != RPC_AUTH_UNIX)
if (dom->flavour != &svcauth_unix)
return -EINVAL;
udom = container_of(dom, struct unix_domain, h);
strcpy(ip.m_class, "nfsd");
Expand All @@ -295,7 +289,7 @@ int auth_unix_forget_old(struct auth_domain *dom)
{
struct unix_domain *udom;

if (dom->flavour != RPC_AUTH_UNIX)
if (dom->flavour != &svcauth_unix)
return -EINVAL;
udom = container_of(dom, struct unix_domain, h);
udom->addr_changes++;
Expand Down Expand Up @@ -323,7 +317,7 @@ struct auth_domain *auth_unix_lookup(struct in_addr addr)
rv = NULL;
} else {
rv = &ipm->m_client->h;
cache_get(&rv->h);
kref_get(&rv->ref);
}
ip_map_put(&ipm->h, &ip_map_cache);
return rv;
Expand All @@ -332,7 +326,6 @@ struct auth_domain *auth_unix_lookup(struct in_addr addr)
void svcauth_unix_purge(void)
{
cache_purge(&ip_map_cache);
cache_purge(&auth_domain_cache);
}

static int
Expand Down Expand Up @@ -361,7 +354,7 @@ svcauth_unix_set_client(struct svc_rqst *rqstp)
return SVC_DENIED;
case 0:
rqstp->rq_client = &ipm->m_client->h;
cache_get(&rqstp->rq_client->h);
kref_get(&rqstp->rq_client->ref);
ip_map_put(&ipm->h, &ip_map_cache);
break;
}
Expand Down

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