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-rw-r--r--net/dccp/ccid.c254
1 files changed, 96 insertions, 158 deletions
diff --git a/net/dccp/ccid.c b/net/dccp/ccid.c
index bcc643f992ae..f3e9ba1cfd01 100644
--- a/net/dccp/ccid.c
+++ b/net/dccp/ccid.c
@@ -12,56 +12,70 @@
*/
#include "ccid.h"
+#include "ccids/lib/tfrc.h"
-static u8 builtin_ccids[] = {
- DCCPC_CCID2, /* CCID2 is supported by default */
-#if defined(CONFIG_IP_DCCP_CCID3) || defined(CONFIG_IP_DCCP_CCID3_MODULE)
- DCCPC_CCID3,
+static struct ccid_operations *ccids[] = {
+ &ccid2_ops,
+#ifdef CONFIG_IP_DCCP_CCID3
+ &ccid3_ops,
#endif
};
-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)
+static struct ccid_operations *ccid_by_number(const u8 id)
{
- spin_lock(&ccids_lock);
- while (atomic_read(&ccids_lockct) != 0) {
- spin_unlock(&ccids_lock);
- yield();
- spin_lock(&ccids_lock);
- }
+ int i;
+
+ for (i = 0; i < ARRAY_SIZE(ccids); i++)
+ if (ccids[i]->ccid_id == id)
+ return ccids[i];
+ return NULL;
}
-static inline void ccids_write_unlock(void)
+/* check that up to @array_len members in @ccid_array are supported */
+bool ccid_support_check(u8 const *ccid_array, u8 array_len)
{
- spin_unlock(&ccids_lock);
+ while (array_len > 0)
+ if (ccid_by_number(ccid_array[--array_len]) == NULL)
+ return false;
+ return true;
}
-static inline void ccids_read_lock(void)
+/**
+ * ccid_get_builtin_ccids - Populate a list of built-in CCIDs
+ * @ccid_array: pointer to copy into
+ * @array_len: value to return length into
+ * This function allocates memory - caller must see that it is freed after use.
+ */
+int ccid_get_builtin_ccids(u8 **ccid_array, u8 *array_len)
{
- atomic_inc(&ccids_lockct);
- smp_mb__after_atomic_inc();
- spin_unlock_wait(&ccids_lock);
+ *ccid_array = kmalloc(ARRAY_SIZE(ccids), gfp_any());
+ if (*ccid_array == NULL)
+ return -ENOBUFS;
+
+ for (*array_len = 0; *array_len < ARRAY_SIZE(ccids); *array_len += 1)
+ (*ccid_array)[*array_len] = ccids[*array_len]->ccid_id;
+ return 0;
}
-static inline void ccids_read_unlock(void)
+int ccid_getsockopt_builtin_ccids(struct sock *sk, int len,
+ char __user *optval, int __user *optlen)
{
- atomic_dec(&ccids_lockct);
-}
+ u8 *ccid_array, array_len;
+ int err = 0;
-#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
+ if (len < ARRAY_SIZE(ccids))
+ return -EINVAL;
+
+ if (ccid_get_builtin_ccids(&ccid_array, &array_len))
+ return -ENOBUFS;
+
+ if (put_user(array_len, optlen) ||
+ copy_to_user(optval, ccid_array, array_len))
+ err = -EFAULT;
+
+ kfree(ccid_array);
+ return err;
+}
static struct kmem_cache *ccid_kmem_cache_create(int obj_size, const char *fmt,...)
{
@@ -93,48 +107,7 @@ static void ccid_kmem_cache_destroy(struct kmem_cache *slab)
}
}
-/* check that up to @array_len members in @ccid_array are supported */
-bool ccid_support_check(u8 const *ccid_array, u8 array_len)
-{
- u8 i, j, found;
-
- for (i = 0, found = 0; i < array_len; i++, found = 0) {
- for (j = 0; !found && j < ARRAY_SIZE(builtin_ccids); j++)
- found = (ccid_array[i] == builtin_ccids[j]);
- if (!found)
- return false;
- }
- return true;
-}
-
-/**
- * ccid_get_builtin_ccids - Provide copy of `builtin' CCID array
- * @ccid_array: pointer to copy into
- * @array_len: value to return length into
- * This function allocates memory - caller must see that it is freed after use.
- */
-int ccid_get_builtin_ccids(u8 **ccid_array, u8 *array_len)
-{
- *ccid_array = kmemdup(builtin_ccids, sizeof(builtin_ccids), gfp_any());
- if (*ccid_array == NULL)
- return -ENOBUFS;
- *array_len = ARRAY_SIZE(builtin_ccids);
- return 0;
-}
-
-int ccid_getsockopt_builtin_ccids(struct sock *sk, int len,
- char __user *optval, int __user *optlen)
-{
- if (len < sizeof(builtin_ccids))
- return -EINVAL;
-
- if (put_user(sizeof(builtin_ccids), optlen) ||
- copy_to_user(optval, builtin_ccids, sizeof(builtin_ccids)))
- return -EFAULT;
- return 0;
-}
-
-int ccid_register(struct ccid_operations *ccid_ops)
+static int ccid_activate(struct ccid_operations *ccid_ops)
{
int err = -ENOBUFS;
@@ -152,79 +125,40 @@ int ccid_register(struct ccid_operations *ccid_ops)
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",
+ pr_info("CCID: Activated CCID %d (%s)\n",
ccid_ops->ccid_id, ccid_ops->ccid_name);
+ err = 0;
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)
+static void ccid_deactivate(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",
+ pr_info("CCID: Deactivated 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 *ccid_new(const u8 id, struct sock *sk, bool rx)
{
- struct ccid_operations *ccid_ops;
+ struct ccid_operations *ccid_ops = ccid_by_number(id);
struct ccid *ccid = NULL;
- ccids_read_lock();
-#ifdef CONFIG_MODULES
- 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();
+ goto out;
ccid = kmem_cache_alloc(rx ? ccid_ops->ccid_hc_rx_slab :
- ccid_ops->ccid_hc_tx_slab, gfp);
+ ccid_ops->ccid_hc_tx_slab, gfp_any());
if (ccid == NULL)
- goto out_module_put;
+ goto out;
ccid->ccid_ops = ccid_ops;
if (rx) {
memset(ccid + 1, 0, ccid_ops->ccid_hc_rx_obj_size);
@@ -239,53 +173,57 @@ struct ccid *ccid_new(unsigned char id, struct sock *sk, int rx, gfp_t gfp)
}
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);
-
-static void ccid_delete(struct ccid *ccid, struct sock *sk, int rx)
+void ccid_hc_rx_delete(struct ccid *ccid, struct sock *sk)
{
- 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);
+ if (ccid != NULL) {
+ if (ccid->ccid_ops->ccid_hc_rx_exit != NULL)
+ ccid->ccid_ops->ccid_hc_rx_exit(sk);
+ kmem_cache_free(ccid->ccid_ops->ccid_hc_rx_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)
+void ccid_hc_tx_delete(struct ccid *ccid, struct sock *sk)
{
- ccid_delete(ccid, sk, 1);
+ if (ccid != NULL) {
+ if (ccid->ccid_ops->ccid_hc_tx_exit != NULL)
+ ccid->ccid_ops->ccid_hc_tx_exit(sk);
+ kmem_cache_free(ccid->ccid_ops->ccid_hc_tx_slab, ccid);
+ }
}
-EXPORT_SYMBOL_GPL(ccid_hc_rx_delete);
-
-void ccid_hc_tx_delete(struct ccid *ccid, struct sock *sk)
+int __init ccid_initialize_builtins(void)
{
- ccid_delete(ccid, sk, 0);
+ int i, err = tfrc_lib_init();
+
+ if (err)
+ return err;
+
+ for (i = 0; i < ARRAY_SIZE(ccids); i++) {
+ err = ccid_activate(ccids[i]);
+ if (err)
+ goto unwind_registrations;
+ }
+ return 0;
+
+unwind_registrations:
+ while(--i >= 0)
+ ccid_deactivate(ccids[i]);
+ tfrc_lib_exit();
+ return err;
}
-EXPORT_SYMBOL_GPL(ccid_hc_tx_delete);
+void ccid_cleanup_builtins(void)
+{
+ int i;
+
+ for (i = 0; i < ARRAY_SIZE(ccids); i++)
+ ccid_deactivate(ccids[i]);
+ tfrc_lib_exit();
+}