linux/net/dccp/ccid.c
Paul Mundt 20c2df83d2 mm: Remove slab destructors from kmem_cache_create().
Slab destructors were no longer supported after Christoph's
c59def9f22 change. They've been
BUGs for both slab and slub, and slob never supported them
either.

This rips out support for the dtor pointer from kmem_cache_create()
completely and fixes up every single callsite in the kernel (there were
about 224, not including the slab allocator definitions themselves,
or the documentation references).

Signed-off-by: Paul Mundt <lethal@linux-sh.org>
2007-07-20 10:11:58 +09:00

256 lines
5.9 KiB
C

/*
* net/dccp/ccid.c
*
* An implementation of the DCCP protocol
* Arnaldo Carvalho de Melo <acme@conectiva.com.br>
*
* CCID infrastructure
*
* This program is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License version 2 as
* published by the Free Software Foundation.
*/
#include "ccid.h"
static struct ccid_operations *ccids[CCID_MAX];
#if defined(CONFIG_SMP) || defined(CONFIG_PREEMPT)
static atomic_t ccids_lockct = ATOMIC_INIT(0);
static DEFINE_SPINLOCK(ccids_lock);
/*
* The strategy is: modifications ccids vector are short, do not sleep and
* veeery rare, but read access should be free of any exclusive locks.
*/
static void ccids_write_lock(void)
{
spin_lock(&ccids_lock);
while (atomic_read(&ccids_lockct) != 0) {
spin_unlock(&ccids_lock);
yield();
spin_lock(&ccids_lock);
}
}
static inline void ccids_write_unlock(void)
{
spin_unlock(&ccids_lock);
}
static inline void ccids_read_lock(void)
{
atomic_inc(&ccids_lockct);
spin_unlock_wait(&ccids_lock);
}
static inline void ccids_read_unlock(void)
{
atomic_dec(&ccids_lockct);
}
#else
#define ccids_write_lock() do { } while(0)
#define ccids_write_unlock() do { } while(0)
#define ccids_read_lock() do { } while(0)
#define ccids_read_unlock() do { } while(0)
#endif
static struct kmem_cache *ccid_kmem_cache_create(int obj_size, const char *fmt,...)
{
struct kmem_cache *slab;
char slab_name_fmt[32], *slab_name;
va_list args;
va_start(args, fmt);
vsnprintf(slab_name_fmt, sizeof(slab_name_fmt), fmt, args);
va_end(args);
slab_name = kstrdup(slab_name_fmt, GFP_KERNEL);
if (slab_name == NULL)
return NULL;
slab = kmem_cache_create(slab_name, sizeof(struct ccid) + obj_size, 0,
SLAB_HWCACHE_ALIGN, NULL);
if (slab == NULL)
kfree(slab_name);
return slab;
}
static void ccid_kmem_cache_destroy(struct kmem_cache *slab)
{
if (slab != NULL) {
const char *name = kmem_cache_name(slab);
kmem_cache_destroy(slab);
kfree(name);
}
}
int ccid_register(struct ccid_operations *ccid_ops)
{
int err = -ENOBUFS;
ccid_ops->ccid_hc_rx_slab =
ccid_kmem_cache_create(ccid_ops->ccid_hc_rx_obj_size,
"%s_hc_rx_sock",
ccid_ops->ccid_name);
if (ccid_ops->ccid_hc_rx_slab == NULL)
goto out;
ccid_ops->ccid_hc_tx_slab =
ccid_kmem_cache_create(ccid_ops->ccid_hc_tx_obj_size,
"%s_hc_tx_sock",
ccid_ops->ccid_name);
if (ccid_ops->ccid_hc_tx_slab == NULL)
goto out_free_rx_slab;
ccids_write_lock();
err = -EEXIST;
if (ccids[ccid_ops->ccid_id] == NULL) {
ccids[ccid_ops->ccid_id] = ccid_ops;
err = 0;
}
ccids_write_unlock();
if (err != 0)
goto out_free_tx_slab;
pr_info("CCID: Registered CCID %d (%s)\n",
ccid_ops->ccid_id, ccid_ops->ccid_name);
out:
return err;
out_free_tx_slab:
ccid_kmem_cache_destroy(ccid_ops->ccid_hc_tx_slab);
ccid_ops->ccid_hc_tx_slab = NULL;
goto out;
out_free_rx_slab:
ccid_kmem_cache_destroy(ccid_ops->ccid_hc_rx_slab);
ccid_ops->ccid_hc_rx_slab = NULL;
goto out;
}
EXPORT_SYMBOL_GPL(ccid_register);
int ccid_unregister(struct ccid_operations *ccid_ops)
{
ccids_write_lock();
ccids[ccid_ops->ccid_id] = NULL;
ccids_write_unlock();
ccid_kmem_cache_destroy(ccid_ops->ccid_hc_tx_slab);
ccid_ops->ccid_hc_tx_slab = NULL;
ccid_kmem_cache_destroy(ccid_ops->ccid_hc_rx_slab);
ccid_ops->ccid_hc_rx_slab = NULL;
pr_info("CCID: Unregistered CCID %d (%s)\n",
ccid_ops->ccid_id, ccid_ops->ccid_name);
return 0;
}
EXPORT_SYMBOL_GPL(ccid_unregister);
struct ccid *ccid_new(unsigned char id, struct sock *sk, int rx, gfp_t gfp)
{
struct ccid_operations *ccid_ops;
struct ccid *ccid = NULL;
ccids_read_lock();
#ifdef CONFIG_KMOD
if (ccids[id] == NULL) {
/* We only try to load if in process context */
ccids_read_unlock();
if (gfp & GFP_ATOMIC)
goto out;
request_module("net-dccp-ccid-%d", id);
ccids_read_lock();
}
#endif
ccid_ops = ccids[id];
if (ccid_ops == NULL)
goto out_unlock;
if (!try_module_get(ccid_ops->ccid_owner))
goto out_unlock;
ccids_read_unlock();
ccid = kmem_cache_alloc(rx ? ccid_ops->ccid_hc_rx_slab :
ccid_ops->ccid_hc_tx_slab, gfp);
if (ccid == NULL)
goto out_module_put;
ccid->ccid_ops = ccid_ops;
if (rx) {
memset(ccid + 1, 0, ccid_ops->ccid_hc_rx_obj_size);
if (ccid->ccid_ops->ccid_hc_rx_init != NULL &&
ccid->ccid_ops->ccid_hc_rx_init(ccid, sk) != 0)
goto out_free_ccid;
} else {
memset(ccid + 1, 0, ccid_ops->ccid_hc_tx_obj_size);
if (ccid->ccid_ops->ccid_hc_tx_init != NULL &&
ccid->ccid_ops->ccid_hc_tx_init(ccid, sk) != 0)
goto out_free_ccid;
}
out:
return ccid;
out_unlock:
ccids_read_unlock();
goto out;
out_free_ccid:
kmem_cache_free(rx ? ccid_ops->ccid_hc_rx_slab :
ccid_ops->ccid_hc_tx_slab, ccid);
ccid = NULL;
out_module_put:
module_put(ccid_ops->ccid_owner);
goto out;
}
EXPORT_SYMBOL_GPL(ccid_new);
struct ccid *ccid_hc_rx_new(unsigned char id, struct sock *sk, gfp_t gfp)
{
return ccid_new(id, sk, 1, gfp);
}
EXPORT_SYMBOL_GPL(ccid_hc_rx_new);
struct ccid *ccid_hc_tx_new(unsigned char id,struct sock *sk, gfp_t gfp)
{
return ccid_new(id, sk, 0, gfp);
}
EXPORT_SYMBOL_GPL(ccid_hc_tx_new);
static void ccid_delete(struct ccid *ccid, struct sock *sk, int rx)
{
struct ccid_operations *ccid_ops;
if (ccid == NULL)
return;
ccid_ops = ccid->ccid_ops;
if (rx) {
if (ccid_ops->ccid_hc_rx_exit != NULL)
ccid_ops->ccid_hc_rx_exit(sk);
kmem_cache_free(ccid_ops->ccid_hc_rx_slab, ccid);
} else {
if (ccid_ops->ccid_hc_tx_exit != NULL)
ccid_ops->ccid_hc_tx_exit(sk);
kmem_cache_free(ccid_ops->ccid_hc_tx_slab, ccid);
}
ccids_read_lock();
if (ccids[ccid_ops->ccid_id] != NULL)
module_put(ccid_ops->ccid_owner);
ccids_read_unlock();
}
void ccid_hc_rx_delete(struct ccid *ccid, struct sock *sk)
{
ccid_delete(ccid, sk, 1);
}
EXPORT_SYMBOL_GPL(ccid_hc_rx_delete);
void ccid_hc_tx_delete(struct ccid *ccid, struct sock *sk)
{
ccid_delete(ccid, sk, 0);
}
EXPORT_SYMBOL_GPL(ccid_hc_tx_delete);