Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt...

[cascardo/linux.git] / include / linux / posix_acl.h

diff --git a/include/linux/posix_acl.h b/include/linux/posix_acl.h
index 9a53b99..b768110 100644 (file)
--- a/include/linux/posix_acl.h
+++ b/include/linux/posix_acl.h
@@ -9,6 +9,7 @@
 #define __LINUX_POSIX_ACL_H
 
 #include <linux/slab.h>
+#include <linux/rcupdate.h>
 
 #define ACL_UNDEFINED_ID       (-1)
 
@@ -38,7 +39,10 @@ struct posix_acl_entry {
 };
 
 struct posix_acl {
-       atomic_t                a_refcount;
+       union {
+               atomic_t                a_refcount;
+               struct rcu_head         a_rcu;
+       };
        unsigned int            a_count;
        struct posix_acl_entry  a_entries[0];
 };
@@ -65,7 +69,7 @@ static inline void
 posix_acl_release(struct posix_acl *acl)
 {
        if (acl && atomic_dec_and_test(&acl->a_refcount))
-               kfree(acl);
+               kfree_rcu(acl, a_rcu);
 }
 
 
@@ -75,29 +79,31 @@ extern void posix_acl_init(struct posix_acl *, int);
 extern struct posix_acl *posix_acl_alloc(int, gfp_t);
 extern int posix_acl_valid(const struct posix_acl *);
 extern int posix_acl_permission(struct inode *, const struct posix_acl *, int);
-extern struct posix_acl *posix_acl_from_mode(mode_t, gfp_t);
-extern int posix_acl_equiv_mode(const struct posix_acl *, mode_t *);
-extern int posix_acl_create(struct posix_acl **, gfp_t, mode_t *);
-extern int posix_acl_chmod(struct posix_acl **, gfp_t, mode_t);
+extern struct posix_acl *posix_acl_from_mode(umode_t, gfp_t);
+extern int posix_acl_equiv_mode(const struct posix_acl *, umode_t *);
+extern int posix_acl_create(struct posix_acl **, gfp_t, umode_t *);
+extern int posix_acl_chmod(struct posix_acl **, gfp_t, umode_t);
 
 extern struct posix_acl *get_posix_acl(struct inode *, int);
 extern int set_posix_acl(struct inode *, int, struct posix_acl *);
 
 #ifdef CONFIG_FS_POSIX_ACL
-static inline struct posix_acl *get_cached_acl(struct inode *inode, int type)
+static inline struct posix_acl **acl_by_type(struct inode *inode, int type)
 {
-       struct posix_acl **p, *acl;
        switch (type) {
        case ACL_TYPE_ACCESS:
-               p = &inode->i_acl;
-               break;
+               return &inode->i_acl;
        case ACL_TYPE_DEFAULT:
-               p = &inode->i_default_acl;
-               break;
+               return &inode->i_default_acl;
        default:
-               return ERR_PTR(-EINVAL);
+               BUG();
        }
-       acl = ACCESS_ONCE(*p);
+}
+
+static inline struct posix_acl *get_cached_acl(struct inode *inode, int type)
+{
+       struct posix_acl **p = acl_by_type(inode, type);
+       struct posix_acl *acl = ACCESS_ONCE(*p);
        if (acl) {
                spin_lock(&inode->i_lock);
                acl = *p;
@@ -108,41 +114,20 @@ static inline struct posix_acl *get_cached_acl(struct inode *inode, int type)
        return acl;
 }
 
-static inline int negative_cached_acl(struct inode *inode, int type)
+static inline struct posix_acl *get_cached_acl_rcu(struct inode *inode, int type)
 {
-       struct posix_acl **p, *acl;
-       switch (type) {
-       case ACL_TYPE_ACCESS:
-               p = &inode->i_acl;
-               break;
-       case ACL_TYPE_DEFAULT:
-               p = &inode->i_default_acl;
-               break;
-       default:
-               BUG();
-       }
-       acl = ACCESS_ONCE(*p);
-       if (acl)
-               return 0;
-       return 1;
+       return rcu_dereference(*acl_by_type(inode, type));
 }
 
 static inline void set_cached_acl(struct inode *inode,
                                  int type,
                                  struct posix_acl *acl)
 {
-       struct posix_acl *old = NULL;
+       struct posix_acl **p = acl_by_type(inode, type);
+       struct posix_acl *old;
        spin_lock(&inode->i_lock);
-       switch (type) {
-       case ACL_TYPE_ACCESS:
-               old = inode->i_acl;
-               inode->i_acl = posix_acl_dup(acl);
-               break;
-       case ACL_TYPE_DEFAULT:
-               old = inode->i_default_acl;
-               inode->i_default_acl = posix_acl_dup(acl);
-               break;
-       }
+       old = *p;
+       rcu_assign_pointer(*p, posix_acl_dup(acl));
        spin_unlock(&inode->i_lock);
        if (old != ACL_NOT_CACHED)
                posix_acl_release(old);
@@ -150,18 +135,11 @@ static inline void set_cached_acl(struct inode *inode,
 
 static inline void forget_cached_acl(struct inode *inode, int type)
 {
-       struct posix_acl *old = NULL;
+       struct posix_acl **p = acl_by_type(inode, type);
+       struct posix_acl *old;
        spin_lock(&inode->i_lock);
-       switch (type) {
-       case ACL_TYPE_ACCESS:
-               old = inode->i_acl;
-               inode->i_acl = ACL_NOT_CACHED;
-               break;
-       case ACL_TYPE_DEFAULT:
-               old = inode->i_default_acl;
-               inode->i_default_acl = ACL_NOT_CACHED;
-               break;
-       }
+       old = *p;
+       *p = ACL_NOT_CACHED;
        spin_unlock(&inode->i_lock);
        if (old != ACL_NOT_CACHED)
                posix_acl_release(old);