diff options
| author | NeilBrown <neilb@suse.com> | 2018-12-03 11:30:30 +1100 |
|---|---|---|
| committer | Anna Schumaker <Anna.Schumaker@Netapp.com> | 2018-12-19 13:52:44 -0500 |
| commit | 97d0fb239c041f5f99655af74812c3ab75cc4346 (patch) | |
| tree | 767e0ff0ed918579b3afb8d9fcd1e37d4143d12b /include/linux/cred.h | |
| parent | d89b22d46a40da3a1630ecea111beaf3ef10bc21 (diff) | |
cred: add get_cred_rcu()
Sometimes we want to opportunistically get a
ref to a cred in an rcu_read_lock protected section.
get_task_cred() does this, and NFS does as similar thing
with its own credential structures.
To prepare for NFS converting to use 'struct cred' more
uniformly, define get_cred_rcu(), and use it in
get_task_cred().
Signed-off-by: NeilBrown <neilb@suse.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
Diffstat (limited to 'include/linux/cred.h')
| -rw-r--r-- | include/linux/cred.h | 11 |
1 files changed, 11 insertions, 0 deletions
diff --git a/include/linux/cred.h b/include/linux/cred.h index f1085767e1b3..48979fcb95cf 100644 --- a/include/linux/cred.h +++ b/include/linux/cred.h @@ -252,6 +252,17 @@ static inline const struct cred *get_cred(const struct cred *cred) return get_new_cred(nonconst_cred); } +static inline const struct cred *get_cred_rcu(const struct cred *cred) +{ + struct cred *nonconst_cred = (struct cred *) cred; + if (!cred) + return NULL; + if (!atomic_inc_not_zero(&nonconst_cred->usage)) + return NULL; + validate_creds(cred); + return cred; +} + /** * put_cred - Release a reference to a set of credentials * @cred: The credentials to release |