KEYS: Add an RCU payload dereference macro

Add an RCU payload dereference macro as this seems to be a common piece of code
amongst key types that use RCU referenced payloads.

Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Mimi Zohar <zohar@us.ibm.com>
Signed-off-by: James Morris <jmorris@namei.org>
This commit is contained in:
David Howells 2011-03-07 15:05:51 +00:00 committed by James Morris
parent 1cc26bada9
commit 633e804e89
4 changed files with 7 additions and 6 deletions

View File

@ -275,6 +275,10 @@ static inline key_serial_t key_serial(struct key *key)
return key ? key->serial : 0;
}
#define rcu_dereference_key(KEY) \
(rcu_dereference_protected((KEY)->payload.rcudata, \
rwsem_is_locked(&((struct key *)(KEY))->sem)))
#ifdef CONFIG_SYSCTL
extern ctl_table key_sysctls[];
#endif

View File

@ -765,8 +765,7 @@ static long encrypted_read(const struct key *key, char __user *buffer,
size_t asciiblob_len;
int ret;
epayload = rcu_dereference_protected(key->payload.data,
rwsem_is_locked(&((struct key *)key)->sem));
epayload = rcu_dereference_key(key);
/* returns the hex encoded iv, encrypted-data, and hmac as ascii */
asciiblob_len = epayload->datablob_len + ivsize + 1

View File

@ -1076,8 +1076,7 @@ static long trusted_read(const struct key *key, char __user *buffer,
char *bufp;
int i;
p = rcu_dereference_protected(key->payload.data,
rwsem_is_locked(&((struct key *)key)->sem));
p = rcu_dereference_key(key);
if (!p)
return -EINVAL;
if (!buffer || buflen <= 0)

View File

@ -184,8 +184,7 @@ long user_read(const struct key *key, char __user *buffer, size_t buflen)
struct user_key_payload *upayload;
long ret;
upayload = rcu_dereference_protected(
key->payload.data, rwsem_is_locked(&((struct key *)key)->sem));
upayload = rcu_dereference_key(key);
ret = upayload->datalen;
/* we can return the data as is */